Line data Source code
1 : /* SPDX-License-Identifier: GPL-2.0-or-later */
2 : /*
3 : * Definitions for the 'struct sk_buff' memory handlers.
4 : *
5 : * Authors:
6 : * Alan Cox, <gw4pts@gw4pts.ampr.org>
7 : * Florian La Roche, <rzsfl@rz.uni-sb.de>
8 : */
9 :
10 : #ifndef _LINUX_SKBUFF_H
11 : #define _LINUX_SKBUFF_H
12 :
13 : #include <linux/kernel.h>
14 : #include <linux/compiler.h>
15 : #include <linux/time.h>
16 : #include <linux/bug.h>
17 : #include <linux/bvec.h>
18 : #include <linux/cache.h>
19 : #include <linux/rbtree.h>
20 : #include <linux/socket.h>
21 : #include <linux/refcount.h>
22 :
23 : #include <linux/atomic.h>
24 : #include <asm/types.h>
25 : #include <linux/spinlock.h>
26 : #include <linux/net.h>
27 : #include <linux/textsearch.h>
28 : #include <net/checksum.h>
29 : #include <linux/rcupdate.h>
30 : #include <linux/hrtimer.h>
31 : #include <linux/dma-mapping.h>
32 : #include <linux/netdev_features.h>
33 : #include <linux/sched.h>
34 : #include <linux/sched/clock.h>
35 : #include <net/flow_dissector.h>
36 : #include <linux/splice.h>
37 : #include <linux/in6.h>
38 : #include <linux/if_packet.h>
39 : #include <net/flow.h>
40 : #if IS_ENABLED(CONFIG_NF_CONNTRACK)
41 : #include <linux/netfilter/nf_conntrack_common.h>
42 : #endif
43 :
44 : /* The interface for checksum offload between the stack and networking drivers
45 : * is as follows...
46 : *
47 : * A. IP checksum related features
48 : *
49 : * Drivers advertise checksum offload capabilities in the features of a device.
50 : * From the stack's point of view these are capabilities offered by the driver.
51 : * A driver typically only advertises features that it is capable of offloading
52 : * to its device.
53 : *
54 : * The checksum related features are:
55 : *
56 : * NETIF_F_HW_CSUM - The driver (or its device) is able to compute one
57 : * IP (one's complement) checksum for any combination
58 : * of protocols or protocol layering. The checksum is
59 : * computed and set in a packet per the CHECKSUM_PARTIAL
60 : * interface (see below).
61 : *
62 : * NETIF_F_IP_CSUM - Driver (device) is only able to checksum plain
63 : * TCP or UDP packets over IPv4. These are specifically
64 : * unencapsulated packets of the form IPv4|TCP or
65 : * IPv4|UDP where the Protocol field in the IPv4 header
66 : * is TCP or UDP. The IPv4 header may contain IP options.
67 : * This feature cannot be set in features for a device
68 : * with NETIF_F_HW_CSUM also set. This feature is being
69 : * DEPRECATED (see below).
70 : *
71 : * NETIF_F_IPV6_CSUM - Driver (device) is only able to checksum plain
72 : * TCP or UDP packets over IPv6. These are specifically
73 : * unencapsulated packets of the form IPv6|TCP or
74 : * IPv6|UDP where the Next Header field in the IPv6
75 : * header is either TCP or UDP. IPv6 extension headers
76 : * are not supported with this feature. This feature
77 : * cannot be set in features for a device with
78 : * NETIF_F_HW_CSUM also set. This feature is being
79 : * DEPRECATED (see below).
80 : *
81 : * NETIF_F_RXCSUM - Driver (device) performs receive checksum offload.
82 : * This flag is only used to disable the RX checksum
83 : * feature for a device. The stack will accept receive
84 : * checksum indication in packets received on a device
85 : * regardless of whether NETIF_F_RXCSUM is set.
86 : *
87 : * B. Checksumming of received packets by device. Indication of checksum
88 : * verification is set in skb->ip_summed. Possible values are:
89 : *
90 : * CHECKSUM_NONE:
91 : *
92 : * Device did not checksum this packet e.g. due to lack of capabilities.
93 : * The packet contains full (though not verified) checksum in packet but
94 : * not in skb->csum. Thus, skb->csum is undefined in this case.
95 : *
96 : * CHECKSUM_UNNECESSARY:
97 : *
98 : * The hardware you're dealing with doesn't calculate the full checksum
99 : * (as in CHECKSUM_COMPLETE), but it does parse headers and verify checksums
100 : * for specific protocols. For such packets it will set CHECKSUM_UNNECESSARY
101 : * if their checksums are okay. skb->csum is still undefined in this case
102 : * though. A driver or device must never modify the checksum field in the
103 : * packet even if checksum is verified.
104 : *
105 : * CHECKSUM_UNNECESSARY is applicable to following protocols:
106 : * TCP: IPv6 and IPv4.
107 : * UDP: IPv4 and IPv6. A device may apply CHECKSUM_UNNECESSARY to a
108 : * zero UDP checksum for either IPv4 or IPv6, the networking stack
109 : * may perform further validation in this case.
110 : * GRE: only if the checksum is present in the header.
111 : * SCTP: indicates the CRC in SCTP header has been validated.
112 : * FCOE: indicates the CRC in FC frame has been validated.
113 : *
114 : * skb->csum_level indicates the number of consecutive checksums found in
115 : * the packet minus one that have been verified as CHECKSUM_UNNECESSARY.
116 : * For instance if a device receives an IPv6->UDP->GRE->IPv4->TCP packet
117 : * and a device is able to verify the checksums for UDP (possibly zero),
118 : * GRE (checksum flag is set) and TCP, skb->csum_level would be set to
119 : * two. If the device were only able to verify the UDP checksum and not
120 : * GRE, either because it doesn't support GRE checksum or because GRE
121 : * checksum is bad, skb->csum_level would be set to zero (TCP checksum is
122 : * not considered in this case).
123 : *
124 : * CHECKSUM_COMPLETE:
125 : *
126 : * This is the most generic way. The device supplied checksum of the _whole_
127 : * packet as seen by netif_rx() and fills in skb->csum. This means the
128 : * hardware doesn't need to parse L3/L4 headers to implement this.
129 : *
130 : * Notes:
131 : * - Even if device supports only some protocols, but is able to produce
132 : * skb->csum, it MUST use CHECKSUM_COMPLETE, not CHECKSUM_UNNECESSARY.
133 : * - CHECKSUM_COMPLETE is not applicable to SCTP and FCoE protocols.
134 : *
135 : * CHECKSUM_PARTIAL:
136 : *
137 : * A checksum is set up to be offloaded to a device as described in the
138 : * output description for CHECKSUM_PARTIAL. This may occur on a packet
139 : * received directly from another Linux OS, e.g., a virtualized Linux kernel
140 : * on the same host, or it may be set in the input path in GRO or remote
141 : * checksum offload. For the purposes of checksum verification, the checksum
142 : * referred to by skb->csum_start + skb->csum_offset and any preceding
143 : * checksums in the packet are considered verified. Any checksums in the
144 : * packet that are after the checksum being offloaded are not considered to
145 : * be verified.
146 : *
147 : * C. Checksumming on transmit for non-GSO. The stack requests checksum offload
148 : * in the skb->ip_summed for a packet. Values are:
149 : *
150 : * CHECKSUM_PARTIAL:
151 : *
152 : * The driver is required to checksum the packet as seen by hard_start_xmit()
153 : * from skb->csum_start up to the end, and to record/write the checksum at
154 : * offset skb->csum_start + skb->csum_offset. A driver may verify that the
155 : * csum_start and csum_offset values are valid values given the length and
156 : * offset of the packet, but it should not attempt to validate that the
157 : * checksum refers to a legitimate transport layer checksum -- it is the
158 : * purview of the stack to validate that csum_start and csum_offset are set
159 : * correctly.
160 : *
161 : * When the stack requests checksum offload for a packet, the driver MUST
162 : * ensure that the checksum is set correctly. A driver can either offload the
163 : * checksum calculation to the device, or call skb_checksum_help (in the case
164 : * that the device does not support offload for a particular checksum).
165 : *
166 : * NETIF_F_IP_CSUM and NETIF_F_IPV6_CSUM are being deprecated in favor of
167 : * NETIF_F_HW_CSUM. New devices should use NETIF_F_HW_CSUM to indicate
168 : * checksum offload capability.
169 : * skb_csum_hwoffload_help() can be called to resolve CHECKSUM_PARTIAL based
170 : * on network device checksumming capabilities: if a packet does not match
171 : * them, skb_checksum_help or skb_crc32c_help (depending on the value of
172 : * csum_not_inet, see item D.) is called to resolve the checksum.
173 : *
174 : * CHECKSUM_NONE:
175 : *
176 : * The skb was already checksummed by the protocol, or a checksum is not
177 : * required.
178 : *
179 : * CHECKSUM_UNNECESSARY:
180 : *
181 : * This has the same meaning as CHECKSUM_NONE for checksum offload on
182 : * output.
183 : *
184 : * CHECKSUM_COMPLETE:
185 : * Not used in checksum output. If a driver observes a packet with this value
186 : * set in skbuff, it should treat the packet as if CHECKSUM_NONE were set.
187 : *
188 : * D. Non-IP checksum (CRC) offloads
189 : *
190 : * NETIF_F_SCTP_CRC - This feature indicates that a device is capable of
191 : * offloading the SCTP CRC in a packet. To perform this offload the stack
192 : * will set csum_start and csum_offset accordingly, set ip_summed to
193 : * CHECKSUM_PARTIAL and set csum_not_inet to 1, to provide an indication in
194 : * the skbuff that the CHECKSUM_PARTIAL refers to CRC32c.
195 : * A driver that supports both IP checksum offload and SCTP CRC32c offload
196 : * must verify which offload is configured for a packet by testing the
197 : * value of skb->csum_not_inet; skb_crc32c_csum_help is provided to resolve
198 : * CHECKSUM_PARTIAL on skbs where csum_not_inet is set to 1.
199 : *
200 : * NETIF_F_FCOE_CRC - This feature indicates that a device is capable of
201 : * offloading the FCOE CRC in a packet. To perform this offload the stack
202 : * will set ip_summed to CHECKSUM_PARTIAL and set csum_start and csum_offset
203 : * accordingly. Note that there is no indication in the skbuff that the
204 : * CHECKSUM_PARTIAL refers to an FCOE checksum, so a driver that supports
205 : * both IP checksum offload and FCOE CRC offload must verify which offload
206 : * is configured for a packet, presumably by inspecting packet headers.
207 : *
208 : * E. Checksumming on output with GSO.
209 : *
210 : * In the case of a GSO packet (skb_is_gso(skb) is true), checksum offload
211 : * is implied by the SKB_GSO_* flags in gso_type. Most obviously, if the
212 : * gso_type is SKB_GSO_TCPV4 or SKB_GSO_TCPV6, TCP checksum offload as
213 : * part of the GSO operation is implied. If a checksum is being offloaded
214 : * with GSO then ip_summed is CHECKSUM_PARTIAL, and both csum_start and
215 : * csum_offset are set to refer to the outermost checksum being offloaded
216 : * (two offloaded checksums are possible with UDP encapsulation).
217 : */
218 :
219 : /* Don't change this without changing skb_csum_unnecessary! */
220 : #define CHECKSUM_NONE 0
221 : #define CHECKSUM_UNNECESSARY 1
222 : #define CHECKSUM_COMPLETE 2
223 : #define CHECKSUM_PARTIAL 3
224 :
225 : /* Maximum value in skb->csum_level */
226 : #define SKB_MAX_CSUM_LEVEL 3
227 :
228 : #define SKB_DATA_ALIGN(X) ALIGN(X, SMP_CACHE_BYTES)
229 : #define SKB_WITH_OVERHEAD(X) \
230 : ((X) - SKB_DATA_ALIGN(sizeof(struct skb_shared_info)))
231 : #define SKB_MAX_ORDER(X, ORDER) \
232 : SKB_WITH_OVERHEAD((PAGE_SIZE << (ORDER)) - (X))
233 : #define SKB_MAX_HEAD(X) (SKB_MAX_ORDER((X), 0))
234 : #define SKB_MAX_ALLOC (SKB_MAX_ORDER(0, 2))
235 :
236 : /* return minimum truesize of one skb containing X bytes of data */
237 : #define SKB_TRUESIZE(X) ((X) + \
238 : SKB_DATA_ALIGN(sizeof(struct sk_buff)) + \
239 : SKB_DATA_ALIGN(sizeof(struct skb_shared_info)))
240 :
241 : struct ahash_request;
242 : struct net_device;
243 : struct scatterlist;
244 : struct pipe_inode_info;
245 : struct iov_iter;
246 : struct napi_struct;
247 : struct bpf_prog;
248 : union bpf_attr;
249 : struct skb_ext;
250 :
251 : #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
252 : struct nf_bridge_info {
253 : enum {
254 : BRNF_PROTO_UNCHANGED,
255 : BRNF_PROTO_8021Q,
256 : BRNF_PROTO_PPPOE
257 : } orig_proto:8;
258 : u8 pkt_otherhost:1;
259 : u8 in_prerouting:1;
260 : u8 bridged_dnat:1;
261 : __u16 frag_max_size;
262 : struct net_device *physindev;
263 :
264 : /* always valid & non-NULL from FORWARD on, for physdev match */
265 : struct net_device *physoutdev;
266 : union {
267 : /* prerouting: detect dnat in orig/reply direction */
268 : __be32 ipv4_daddr;
269 : struct in6_addr ipv6_daddr;
270 :
271 : /* after prerouting + nat detected: store original source
272 : * mac since neigh resolution overwrites it, only used while
273 : * skb is out in neigh layer.
274 : */
275 : char neigh_header[8];
276 : };
277 : };
278 : #endif
279 :
280 : #if IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
281 : /* Chain in tc_skb_ext will be used to share the tc chain with
282 : * ovs recirc_id. It will be set to the current chain by tc
283 : * and read by ovs to recirc_id.
284 : */
285 : struct tc_skb_ext {
286 : __u32 chain;
287 : __u16 mru;
288 : };
289 : #endif
290 :
291 : struct sk_buff_head {
292 : /* These two members must be first. */
293 : struct sk_buff *next;
294 : struct sk_buff *prev;
295 :
296 : __u32 qlen;
297 : spinlock_t lock;
298 : };
299 :
300 : struct sk_buff;
301 :
302 : /* To allow 64K frame to be packed as single skb without frag_list we
303 : * require 64K/PAGE_SIZE pages plus 1 additional page to allow for
304 : * buffers which do not start on a page boundary.
305 : *
306 : * Since GRO uses frags we allocate at least 16 regardless of page
307 : * size.
308 : */
309 : #if (65536/PAGE_SIZE + 1) < 16
310 : #define MAX_SKB_FRAGS 16UL
311 : #else
312 : #define MAX_SKB_FRAGS (65536/PAGE_SIZE + 1)
313 : #endif
314 : extern int sysctl_max_skb_frags;
315 :
316 : /* Set skb_shinfo(skb)->gso_size to this in case you want skb_segment to
317 : * segment using its current segmentation instead.
318 : */
319 : #define GSO_BY_FRAGS 0xFFFF
320 :
321 : typedef struct bio_vec skb_frag_t;
322 :
323 : /**
324 : * skb_frag_size() - Returns the size of a skb fragment
325 : * @frag: skb fragment
326 : */
327 1481 : static inline unsigned int skb_frag_size(const skb_frag_t *frag)
328 : {
329 1070 : return frag->bv_len;
330 : }
331 :
332 : /**
333 : * skb_frag_size_set() - Sets the size of a skb fragment
334 : * @frag: skb fragment
335 : * @size: size of fragment
336 : */
337 691 : static inline void skb_frag_size_set(skb_frag_t *frag, unsigned int size)
338 : {
339 361 : frag->bv_len = size;
340 0 : }
341 :
342 : /**
343 : * skb_frag_size_add() - Increments the size of a skb fragment by @delta
344 : * @frag: skb fragment
345 : * @delta: value to add
346 : */
347 50 : static inline void skb_frag_size_add(skb_frag_t *frag, int delta)
348 : {
349 50 : frag->bv_len += delta;
350 50 : }
351 :
352 : /**
353 : * skb_frag_size_sub() - Decrements the size of a skb fragment by @delta
354 : * @frag: skb fragment
355 : * @delta: value to subtract
356 : */
357 0 : static inline void skb_frag_size_sub(skb_frag_t *frag, int delta)
358 : {
359 0 : frag->bv_len -= delta;
360 0 : }
361 :
362 : /**
363 : * skb_frag_must_loop - Test if %p is a high memory page
364 : * @p: fragment's page
365 : */
366 685 : static inline bool skb_frag_must_loop(struct page *p)
367 : {
368 : #if defined(CONFIG_HIGHMEM)
369 : if (IS_ENABLED(CONFIG_DEBUG_KMAP_LOCAL_FORCE_MAP) || PageHighMem(p))
370 : return true;
371 : #endif
372 685 : return false;
373 : }
374 :
375 : /**
376 : * skb_frag_foreach_page - loop over pages in a fragment
377 : *
378 : * @f: skb frag to operate on
379 : * @f_off: offset from start of f->bv_page
380 : * @f_len: length from f_off to loop over
381 : * @p: (temp var) current page
382 : * @p_off: (temp var) offset from start of current page,
383 : * non-zero only on first page.
384 : * @p_len: (temp var) length in current page,
385 : * < PAGE_SIZE only on first and last page.
386 : * @copied: (temp var) length so far, excluding current p_len.
387 : *
388 : * A fragment can hold a compound page, in which case per-page
389 : * operations, notably kmap_atomic, must be called for each
390 : * regular page.
391 : */
392 : #define skb_frag_foreach_page(f, f_off, f_len, p, p_off, p_len, copied) \
393 : for (p = skb_frag_page(f) + ((f_off) >> PAGE_SHIFT), \
394 : p_off = (f_off) & (PAGE_SIZE - 1), \
395 : p_len = skb_frag_must_loop(p) ? \
396 : min_t(u32, f_len, PAGE_SIZE - p_off) : f_len, \
397 : copied = 0; \
398 : copied < f_len; \
399 : copied += p_len, p++, p_off = 0, \
400 : p_len = min_t(u32, f_len - copied, PAGE_SIZE)) \
401 :
402 : #define HAVE_HW_TIME_STAMP
403 :
404 : /**
405 : * struct skb_shared_hwtstamps - hardware time stamps
406 : * @hwtstamp: hardware time stamp transformed into duration
407 : * since arbitrary point in time
408 : *
409 : * Software time stamps generated by ktime_get_real() are stored in
410 : * skb->tstamp.
411 : *
412 : * hwtstamps can only be compared against other hwtstamps from
413 : * the same device.
414 : *
415 : * This structure is attached to packets as part of the
416 : * &skb_shared_info. Use skb_hwtstamps() to get a pointer.
417 : */
418 : struct skb_shared_hwtstamps {
419 : ktime_t hwtstamp;
420 : };
421 :
422 : /* Definitions for tx_flags in struct skb_shared_info */
423 : enum {
424 : /* generate hardware time stamp */
425 : SKBTX_HW_TSTAMP = 1 << 0,
426 :
427 : /* generate software time stamp when queueing packet to NIC */
428 : SKBTX_SW_TSTAMP = 1 << 1,
429 :
430 : /* device driver is going to provide hardware time stamp */
431 : SKBTX_IN_PROGRESS = 1 << 2,
432 :
433 : /* generate wifi status information (where possible) */
434 : SKBTX_WIFI_STATUS = 1 << 4,
435 :
436 : /* generate software time stamp when entering packet scheduling */
437 : SKBTX_SCHED_TSTAMP = 1 << 6,
438 : };
439 :
440 : #define SKBTX_ANY_SW_TSTAMP (SKBTX_SW_TSTAMP | \
441 : SKBTX_SCHED_TSTAMP)
442 : #define SKBTX_ANY_TSTAMP (SKBTX_HW_TSTAMP | SKBTX_ANY_SW_TSTAMP)
443 :
444 : /* Definitions for flags in struct skb_shared_info */
445 : enum {
446 : /* use zcopy routines */
447 : SKBFL_ZEROCOPY_ENABLE = BIT(0),
448 :
449 : /* This indicates at least one fragment might be overwritten
450 : * (as in vmsplice(), sendfile() ...)
451 : * If we need to compute a TX checksum, we'll need to copy
452 : * all frags to avoid possible bad checksum
453 : */
454 : SKBFL_SHARED_FRAG = BIT(1),
455 : };
456 :
457 : #define SKBFL_ZEROCOPY_FRAG (SKBFL_ZEROCOPY_ENABLE | SKBFL_SHARED_FRAG)
458 :
459 : /*
460 : * The callback notifies userspace to release buffers when skb DMA is done in
461 : * lower device, the skb last reference should be 0 when calling this.
462 : * The zerocopy_success argument is true if zero copy transmit occurred,
463 : * false on data copy or out of memory error caused by data copy attempt.
464 : * The ctx field is used to track device context.
465 : * The desc field is used to track userspace buffer index.
466 : */
467 : struct ubuf_info {
468 : void (*callback)(struct sk_buff *, struct ubuf_info *,
469 : bool zerocopy_success);
470 : union {
471 : struct {
472 : unsigned long desc;
473 : void *ctx;
474 : };
475 : struct {
476 : u32 id;
477 : u16 len;
478 : u16 zerocopy:1;
479 : u32 bytelen;
480 : };
481 : };
482 : refcount_t refcnt;
483 : u8 flags;
484 :
485 : struct mmpin {
486 : struct user_struct *user;
487 : unsigned int num_pg;
488 : } mmp;
489 : };
490 :
491 : #define skb_uarg(SKB) ((struct ubuf_info *)(skb_shinfo(SKB)->destructor_arg))
492 :
493 : int mm_account_pinned_pages(struct mmpin *mmp, size_t size);
494 : void mm_unaccount_pinned_pages(struct mmpin *mmp);
495 :
496 : struct ubuf_info *msg_zerocopy_alloc(struct sock *sk, size_t size);
497 : struct ubuf_info *msg_zerocopy_realloc(struct sock *sk, size_t size,
498 : struct ubuf_info *uarg);
499 :
500 : void msg_zerocopy_put_abort(struct ubuf_info *uarg, bool have_uref);
501 :
502 : void msg_zerocopy_callback(struct sk_buff *skb, struct ubuf_info *uarg,
503 : bool success);
504 :
505 : int skb_zerocopy_iter_dgram(struct sk_buff *skb, struct msghdr *msg, int len);
506 : int skb_zerocopy_iter_stream(struct sock *sk, struct sk_buff *skb,
507 : struct msghdr *msg, int len,
508 : struct ubuf_info *uarg);
509 :
510 : /* This data is invariant across clones and lives at
511 : * the end of the header data, ie. at skb->end.
512 : */
513 : struct skb_shared_info {
514 : __u8 flags;
515 : __u8 meta_len;
516 : __u8 nr_frags;
517 : __u8 tx_flags;
518 : unsigned short gso_size;
519 : /* Warning: this field is not always filled in (UFO)! */
520 : unsigned short gso_segs;
521 : struct sk_buff *frag_list;
522 : struct skb_shared_hwtstamps hwtstamps;
523 : unsigned int gso_type;
524 : u32 tskey;
525 :
526 : /*
527 : * Warning : all fields before dataref are cleared in __alloc_skb()
528 : */
529 : atomic_t dataref;
530 :
531 : /* Intermediate layers must ensure that destructor_arg
532 : * remains valid until skb destructor */
533 : void * destructor_arg;
534 :
535 : /* must be last field, see pskb_expand_head() */
536 : skb_frag_t frags[MAX_SKB_FRAGS];
537 : };
538 :
539 : /* We divide dataref into two halves. The higher 16 bits hold references
540 : * to the payload part of skb->data. The lower 16 bits hold references to
541 : * the entire skb->data. A clone of a headerless skb holds the length of
542 : * the header in skb->hdr_len.
543 : *
544 : * All users must obey the rule that the skb->data reference count must be
545 : * greater than or equal to the payload reference count.
546 : *
547 : * Holding a reference to the payload part means that the user does not
548 : * care about modifications to the header part of skb->data.
549 : */
550 : #define SKB_DATAREF_SHIFT 16
551 : #define SKB_DATAREF_MASK ((1 << SKB_DATAREF_SHIFT) - 1)
552 :
553 :
554 : enum {
555 : SKB_FCLONE_UNAVAILABLE, /* skb has no fclone (from head_cache) */
556 : SKB_FCLONE_ORIG, /* orig skb (from fclone_cache) */
557 : SKB_FCLONE_CLONE, /* companion fclone skb (from fclone_cache) */
558 : };
559 :
560 : enum {
561 : SKB_GSO_TCPV4 = 1 << 0,
562 :
563 : /* This indicates the skb is from an untrusted source. */
564 : SKB_GSO_DODGY = 1 << 1,
565 :
566 : /* This indicates the tcp segment has CWR set. */
567 : SKB_GSO_TCP_ECN = 1 << 2,
568 :
569 : SKB_GSO_TCP_FIXEDID = 1 << 3,
570 :
571 : SKB_GSO_TCPV6 = 1 << 4,
572 :
573 : SKB_GSO_FCOE = 1 << 5,
574 :
575 : SKB_GSO_GRE = 1 << 6,
576 :
577 : SKB_GSO_GRE_CSUM = 1 << 7,
578 :
579 : SKB_GSO_IPXIP4 = 1 << 8,
580 :
581 : SKB_GSO_IPXIP6 = 1 << 9,
582 :
583 : SKB_GSO_UDP_TUNNEL = 1 << 10,
584 :
585 : SKB_GSO_UDP_TUNNEL_CSUM = 1 << 11,
586 :
587 : SKB_GSO_PARTIAL = 1 << 12,
588 :
589 : SKB_GSO_TUNNEL_REMCSUM = 1 << 13,
590 :
591 : SKB_GSO_SCTP = 1 << 14,
592 :
593 : SKB_GSO_ESP = 1 << 15,
594 :
595 : SKB_GSO_UDP = 1 << 16,
596 :
597 : SKB_GSO_UDP_L4 = 1 << 17,
598 :
599 : SKB_GSO_FRAGLIST = 1 << 18,
600 : };
601 :
602 : #if BITS_PER_LONG > 32
603 : #define NET_SKBUFF_DATA_USES_OFFSET 1
604 : #endif
605 :
606 : #ifdef NET_SKBUFF_DATA_USES_OFFSET
607 : typedef unsigned int sk_buff_data_t;
608 : #else
609 : typedef unsigned char *sk_buff_data_t;
610 : #endif
611 :
612 : /**
613 : * struct sk_buff - socket buffer
614 : * @next: Next buffer in list
615 : * @prev: Previous buffer in list
616 : * @tstamp: Time we arrived/left
617 : * @skb_mstamp_ns: (aka @tstamp) earliest departure time; start point
618 : * for retransmit timer
619 : * @rbnode: RB tree node, alternative to next/prev for netem/tcp
620 : * @list: queue head
621 : * @sk: Socket we are owned by
622 : * @ip_defrag_offset: (aka @sk) alternate use of @sk, used in
623 : * fragmentation management
624 : * @dev: Device we arrived on/are leaving by
625 : * @dev_scratch: (aka @dev) alternate use of @dev when @dev would be %NULL
626 : * @cb: Control buffer. Free for use by every layer. Put private vars here
627 : * @_skb_refdst: destination entry (with norefcount bit)
628 : * @sp: the security path, used for xfrm
629 : * @len: Length of actual data
630 : * @data_len: Data length
631 : * @mac_len: Length of link layer header
632 : * @hdr_len: writable header length of cloned skb
633 : * @csum: Checksum (must include start/offset pair)
634 : * @csum_start: Offset from skb->head where checksumming should start
635 : * @csum_offset: Offset from csum_start where checksum should be stored
636 : * @priority: Packet queueing priority
637 : * @ignore_df: allow local fragmentation
638 : * @cloned: Head may be cloned (check refcnt to be sure)
639 : * @ip_summed: Driver fed us an IP checksum
640 : * @nohdr: Payload reference only, must not modify header
641 : * @pkt_type: Packet class
642 : * @fclone: skbuff clone status
643 : * @ipvs_property: skbuff is owned by ipvs
644 : * @inner_protocol_type: whether the inner protocol is
645 : * ENCAP_TYPE_ETHER or ENCAP_TYPE_IPPROTO
646 : * @remcsum_offload: remote checksum offload is enabled
647 : * @offload_fwd_mark: Packet was L2-forwarded in hardware
648 : * @offload_l3_fwd_mark: Packet was L3-forwarded in hardware
649 : * @tc_skip_classify: do not classify packet. set by IFB device
650 : * @tc_at_ingress: used within tc_classify to distinguish in/egress
651 : * @redirected: packet was redirected by packet classifier
652 : * @from_ingress: packet was redirected from the ingress path
653 : * @peeked: this packet has been seen already, so stats have been
654 : * done for it, don't do them again
655 : * @nf_trace: netfilter packet trace flag
656 : * @protocol: Packet protocol from driver
657 : * @destructor: Destruct function
658 : * @tcp_tsorted_anchor: list structure for TCP (tp->tsorted_sent_queue)
659 : * @_nfct: Associated connection, if any (with nfctinfo bits)
660 : * @nf_bridge: Saved data about a bridged frame - see br_netfilter.c
661 : * @skb_iif: ifindex of device we arrived on
662 : * @tc_index: Traffic control index
663 : * @hash: the packet hash
664 : * @queue_mapping: Queue mapping for multiqueue devices
665 : * @head_frag: skb was allocated from page fragments,
666 : * not allocated by kmalloc() or vmalloc().
667 : * @pfmemalloc: skbuff was allocated from PFMEMALLOC reserves
668 : * @active_extensions: active extensions (skb_ext_id types)
669 : * @ndisc_nodetype: router type (from link layer)
670 : * @ooo_okay: allow the mapping of a socket to a queue to be changed
671 : * @l4_hash: indicate hash is a canonical 4-tuple hash over transport
672 : * ports.
673 : * @sw_hash: indicates hash was computed in software stack
674 : * @wifi_acked_valid: wifi_acked was set
675 : * @wifi_acked: whether frame was acked on wifi or not
676 : * @no_fcs: Request NIC to treat last 4 bytes as Ethernet FCS
677 : * @encapsulation: indicates the inner headers in the skbuff are valid
678 : * @encap_hdr_csum: software checksum is needed
679 : * @csum_valid: checksum is already valid
680 : * @csum_not_inet: use CRC32c to resolve CHECKSUM_PARTIAL
681 : * @csum_complete_sw: checksum was completed by software
682 : * @csum_level: indicates the number of consecutive checksums found in
683 : * the packet minus one that have been verified as
684 : * CHECKSUM_UNNECESSARY (max 3)
685 : * @dst_pending_confirm: need to confirm neighbour
686 : * @decrypted: Decrypted SKB
687 : * @napi_id: id of the NAPI struct this skb came from
688 : * @sender_cpu: (aka @napi_id) source CPU in XPS
689 : * @secmark: security marking
690 : * @mark: Generic packet mark
691 : * @reserved_tailroom: (aka @mark) number of bytes of free space available
692 : * at the tail of an sk_buff
693 : * @vlan_present: VLAN tag is present
694 : * @vlan_proto: vlan encapsulation protocol
695 : * @vlan_tci: vlan tag control information
696 : * @inner_protocol: Protocol (encapsulation)
697 : * @inner_ipproto: (aka @inner_protocol) stores ipproto when
698 : * skb->inner_protocol_type == ENCAP_TYPE_IPPROTO;
699 : * @inner_transport_header: Inner transport layer header (encapsulation)
700 : * @inner_network_header: Network layer header (encapsulation)
701 : * @inner_mac_header: Link layer header (encapsulation)
702 : * @transport_header: Transport layer header
703 : * @network_header: Network layer header
704 : * @mac_header: Link layer header
705 : * @kcov_handle: KCOV remote handle for remote coverage collection
706 : * @tail: Tail pointer
707 : * @end: End pointer
708 : * @head: Head of buffer
709 : * @data: Data head pointer
710 : * @truesize: Buffer size
711 : * @users: User count - see {datagram,tcp}.c
712 : * @extensions: allocated extensions, valid if active_extensions is nonzero
713 : */
714 :
715 : struct sk_buff {
716 : union {
717 : struct {
718 : /* These two members must be first. */
719 : struct sk_buff *next;
720 : struct sk_buff *prev;
721 :
722 : union {
723 : struct net_device *dev;
724 : /* Some protocols might use this space to store information,
725 : * while device pointer would be NULL.
726 : * UDP receive path is one user.
727 : */
728 : unsigned long dev_scratch;
729 : };
730 : };
731 : struct rb_node rbnode; /* used in netem, ip4 defrag, and tcp stack */
732 : struct list_head list;
733 : };
734 :
735 : union {
736 : struct sock *sk;
737 : int ip_defrag_offset;
738 : };
739 :
740 : union {
741 : ktime_t tstamp;
742 : u64 skb_mstamp_ns; /* earliest departure time */
743 : };
744 : /*
745 : * This is the control buffer. It is free to use for every
746 : * layer. Please put your private variables there. If you
747 : * want to keep them across layers you have to do a skb_clone()
748 : * first. This is owned by whoever has the skb queued ATM.
749 : */
750 : char cb[48] __aligned(8);
751 :
752 : union {
753 : struct {
754 : unsigned long _skb_refdst;
755 : void (*destructor)(struct sk_buff *skb);
756 : };
757 : struct list_head tcp_tsorted_anchor;
758 : };
759 :
760 : #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
761 : unsigned long _nfct;
762 : #endif
763 : unsigned int len,
764 : data_len;
765 : __u16 mac_len,
766 : hdr_len;
767 :
768 : /* Following fields are _not_ copied in __copy_skb_header()
769 : * Note that queue_mapping is here mostly to fill a hole.
770 : */
771 : __u16 queue_mapping;
772 :
773 : /* if you move cloned around you also must adapt those constants */
774 : #ifdef __BIG_ENDIAN_BITFIELD
775 : #define CLONED_MASK (1 << 7)
776 : #else
777 : #define CLONED_MASK 1
778 : #endif
779 : #define CLONED_OFFSET() offsetof(struct sk_buff, __cloned_offset)
780 :
781 : /* private: */
782 : __u8 __cloned_offset[0];
783 : /* public: */
784 : __u8 cloned:1,
785 : nohdr:1,
786 : fclone:2,
787 : peeked:1,
788 : head_frag:1,
789 : pfmemalloc:1;
790 : #ifdef CONFIG_SKB_EXTENSIONS
791 : __u8 active_extensions;
792 : #endif
793 : /* fields enclosed in headers_start/headers_end are copied
794 : * using a single memcpy() in __copy_skb_header()
795 : */
796 : /* private: */
797 : __u32 headers_start[0];
798 : /* public: */
799 :
800 : /* if you move pkt_type around you also must adapt those constants */
801 : #ifdef __BIG_ENDIAN_BITFIELD
802 : #define PKT_TYPE_MAX (7 << 5)
803 : #else
804 : #define PKT_TYPE_MAX 7
805 : #endif
806 : #define PKT_TYPE_OFFSET() offsetof(struct sk_buff, __pkt_type_offset)
807 :
808 : /* private: */
809 : __u8 __pkt_type_offset[0];
810 : /* public: */
811 : __u8 pkt_type:3;
812 : __u8 ignore_df:1;
813 : __u8 nf_trace:1;
814 : __u8 ip_summed:2;
815 : __u8 ooo_okay:1;
816 :
817 : __u8 l4_hash:1;
818 : __u8 sw_hash:1;
819 : __u8 wifi_acked_valid:1;
820 : __u8 wifi_acked:1;
821 : __u8 no_fcs:1;
822 : /* Indicates the inner headers are valid in the skbuff. */
823 : __u8 encapsulation:1;
824 : __u8 encap_hdr_csum:1;
825 : __u8 csum_valid:1;
826 :
827 : #ifdef __BIG_ENDIAN_BITFIELD
828 : #define PKT_VLAN_PRESENT_BIT 7
829 : #else
830 : #define PKT_VLAN_PRESENT_BIT 0
831 : #endif
832 : #define PKT_VLAN_PRESENT_OFFSET() offsetof(struct sk_buff, __pkt_vlan_present_offset)
833 : /* private: */
834 : __u8 __pkt_vlan_present_offset[0];
835 : /* public: */
836 : __u8 vlan_present:1;
837 : __u8 csum_complete_sw:1;
838 : __u8 csum_level:2;
839 : __u8 csum_not_inet:1;
840 : __u8 dst_pending_confirm:1;
841 : #ifdef CONFIG_IPV6_NDISC_NODETYPE
842 : __u8 ndisc_nodetype:2;
843 : #endif
844 :
845 : __u8 ipvs_property:1;
846 : __u8 inner_protocol_type:1;
847 : __u8 remcsum_offload:1;
848 : #ifdef CONFIG_NET_SWITCHDEV
849 : __u8 offload_fwd_mark:1;
850 : __u8 offload_l3_fwd_mark:1;
851 : #endif
852 : #ifdef CONFIG_NET_CLS_ACT
853 : __u8 tc_skip_classify:1;
854 : __u8 tc_at_ingress:1;
855 : #endif
856 : #ifdef CONFIG_NET_REDIRECT
857 : __u8 redirected:1;
858 : __u8 from_ingress:1;
859 : #endif
860 : #ifdef CONFIG_TLS_DEVICE
861 : __u8 decrypted:1;
862 : #endif
863 :
864 : #ifdef CONFIG_NET_SCHED
865 : __u16 tc_index; /* traffic control index */
866 : #endif
867 :
868 : union {
869 : __wsum csum;
870 : struct {
871 : __u16 csum_start;
872 : __u16 csum_offset;
873 : };
874 : };
875 : __u32 priority;
876 : int skb_iif;
877 : __u32 hash;
878 : __be16 vlan_proto;
879 : __u16 vlan_tci;
880 : #if defined(CONFIG_NET_RX_BUSY_POLL) || defined(CONFIG_XPS)
881 : union {
882 : unsigned int napi_id;
883 : unsigned int sender_cpu;
884 : };
885 : #endif
886 : #ifdef CONFIG_NETWORK_SECMARK
887 : __u32 secmark;
888 : #endif
889 :
890 : union {
891 : __u32 mark;
892 : __u32 reserved_tailroom;
893 : };
894 :
895 : union {
896 : __be16 inner_protocol;
897 : __u8 inner_ipproto;
898 : };
899 :
900 : __u16 inner_transport_header;
901 : __u16 inner_network_header;
902 : __u16 inner_mac_header;
903 :
904 : __be16 protocol;
905 : __u16 transport_header;
906 : __u16 network_header;
907 : __u16 mac_header;
908 :
909 : #ifdef CONFIG_KCOV
910 : u64 kcov_handle;
911 : #endif
912 :
913 : /* private: */
914 : __u32 headers_end[0];
915 : /* public: */
916 :
917 : /* These elements must be at the end, see alloc_skb() for details. */
918 : sk_buff_data_t tail;
919 : sk_buff_data_t end;
920 : unsigned char *head,
921 : *data;
922 : unsigned int truesize;
923 : refcount_t users;
924 :
925 : #ifdef CONFIG_SKB_EXTENSIONS
926 : /* only useable after checking ->active_extensions != 0 */
927 : struct skb_ext *extensions;
928 : #endif
929 : };
930 :
931 : #ifdef __KERNEL__
932 : /*
933 : * Handling routines are only of interest to the kernel
934 : */
935 :
936 : #define SKB_ALLOC_FCLONE 0x01
937 : #define SKB_ALLOC_RX 0x02
938 : #define SKB_ALLOC_NAPI 0x04
939 :
940 : /**
941 : * skb_pfmemalloc - Test if the skb was allocated from PFMEMALLOC reserves
942 : * @skb: buffer
943 : */
944 3218 : static inline bool skb_pfmemalloc(const struct sk_buff *skb)
945 : {
946 3218 : return unlikely(skb->pfmemalloc);
947 : }
948 :
949 : /*
950 : * skb might have a dst pointer attached, refcounted or not.
951 : * _skb_refdst low order bit is set if refcount was _not_ taken
952 : */
953 : #define SKB_DST_NOREF 1UL
954 : #define SKB_DST_PTRMASK ~(SKB_DST_NOREF)
955 :
956 : /**
957 : * skb_dst - returns skb dst_entry
958 : * @skb: buffer
959 : *
960 : * Returns skb dst_entry, regardless of reference taken or not.
961 : */
962 6838 : static inline struct dst_entry *skb_dst(const struct sk_buff *skb)
963 : {
964 : /* If refdst was not refcounted, check we still are in a
965 : * rcu_read_lock section
966 : */
967 6838 : WARN_ON((skb->_skb_refdst & SKB_DST_NOREF) &&
968 : !rcu_read_lock_held() &&
969 : !rcu_read_lock_bh_held());
970 6838 : return (struct dst_entry *)(skb->_skb_refdst & SKB_DST_PTRMASK);
971 : }
972 :
973 : /**
974 : * skb_dst_set - sets skb dst
975 : * @skb: buffer
976 : * @dst: dst entry
977 : *
978 : * Sets skb dst, assuming a reference was taken on dst and should
979 : * be released by skb_dst_drop()
980 : */
981 25 : static inline void skb_dst_set(struct sk_buff *skb, struct dst_entry *dst)
982 : {
983 25 : skb->_skb_refdst = (unsigned long)dst;
984 0 : }
985 :
986 : /**
987 : * skb_dst_set_noref - sets skb dst, hopefully, without taking reference
988 : * @skb: buffer
989 : * @dst: dst entry
990 : *
991 : * Sets skb dst, assuming a reference was not taken on dst.
992 : * If dst entry is cached, we do not take reference and dst_release
993 : * will be avoided by refdst_drop. If dst entry is not cached, we take
994 : * reference, so that last dst_release can destroy the dst immediately.
995 : */
996 828 : static inline void skb_dst_set_noref(struct sk_buff *skb, struct dst_entry *dst)
997 : {
998 828 : WARN_ON(!rcu_read_lock_held() && !rcu_read_lock_bh_held());
999 828 : skb->_skb_refdst = (unsigned long)dst | SKB_DST_NOREF;
1000 828 : }
1001 :
1002 : /**
1003 : * skb_dst_is_noref - Test if skb dst isn't refcounted
1004 : * @skb: buffer
1005 : */
1006 286 : static inline bool skb_dst_is_noref(const struct sk_buff *skb)
1007 : {
1008 286 : return (skb->_skb_refdst & SKB_DST_NOREF) && skb_dst(skb);
1009 : }
1010 :
1011 : /**
1012 : * skb_rtable - Returns the skb &rtable
1013 : * @skb: buffer
1014 : */
1015 1448 : static inline struct rtable *skb_rtable(const struct sk_buff *skb)
1016 : {
1017 1448 : return (struct rtable *)skb_dst(skb);
1018 : }
1019 :
1020 : /* For mangling skb->pkt_type from user space side from applications
1021 : * such as nft, tc, etc, we only allow a conservative subset of
1022 : * possible pkt_types to be set.
1023 : */
1024 0 : static inline bool skb_pkt_type_ok(u32 ptype)
1025 : {
1026 0 : return ptype <= PACKET_OTHERHOST;
1027 : }
1028 :
1029 : /**
1030 : * skb_napi_id - Returns the skb's NAPI id
1031 : * @skb: buffer
1032 : */
1033 0 : static inline unsigned int skb_napi_id(const struct sk_buff *skb)
1034 : {
1035 : #ifdef CONFIG_NET_RX_BUSY_POLL
1036 0 : return skb->napi_id;
1037 : #else
1038 : return 0;
1039 : #endif
1040 : }
1041 :
1042 : /**
1043 : * skb_unref - decrement the skb's reference count
1044 : * @skb: buffer
1045 : *
1046 : * Returns true if we can free the skb.
1047 : */
1048 9631 : static inline bool skb_unref(struct sk_buff *skb)
1049 : {
1050 9631 : if (unlikely(!skb))
1051 : return false;
1052 8936 : if (likely(refcount_read(&skb->users) == 1))
1053 5249 : smp_rmb();
1054 3687 : else if (likely(!refcount_dec_and_test(&skb->users)))
1055 3687 : return false;
1056 :
1057 : return true;
1058 : }
1059 :
1060 : void skb_release_head_state(struct sk_buff *skb);
1061 : void kfree_skb(struct sk_buff *skb);
1062 : void kfree_skb_list(struct sk_buff *segs);
1063 : void skb_dump(const char *level, const struct sk_buff *skb, bool full_pkt);
1064 : void skb_tx_error(struct sk_buff *skb);
1065 :
1066 : #ifdef CONFIG_TRACEPOINTS
1067 : void consume_skb(struct sk_buff *skb);
1068 : #else
1069 : static inline void consume_skb(struct sk_buff *skb)
1070 : {
1071 : return kfree_skb(skb);
1072 : }
1073 : #endif
1074 :
1075 : void __consume_stateless_skb(struct sk_buff *skb);
1076 : void __kfree_skb(struct sk_buff *skb);
1077 : extern struct kmem_cache *skbuff_head_cache;
1078 :
1079 : void kfree_skb_partial(struct sk_buff *skb, bool head_stolen);
1080 : bool skb_try_coalesce(struct sk_buff *to, struct sk_buff *from,
1081 : bool *fragstolen, int *delta_truesize);
1082 :
1083 : struct sk_buff *__alloc_skb(unsigned int size, gfp_t priority, int flags,
1084 : int node);
1085 : struct sk_buff *__build_skb(void *data, unsigned int frag_size);
1086 : struct sk_buff *build_skb(void *data, unsigned int frag_size);
1087 : struct sk_buff *build_skb_around(struct sk_buff *skb,
1088 : void *data, unsigned int frag_size);
1089 :
1090 : struct sk_buff *napi_build_skb(void *data, unsigned int frag_size);
1091 :
1092 : /**
1093 : * alloc_skb - allocate a network buffer
1094 : * @size: size to allocate
1095 : * @priority: allocation mask
1096 : *
1097 : * This function is a convenient wrapper around __alloc_skb().
1098 : */
1099 3778 : static inline struct sk_buff *alloc_skb(unsigned int size,
1100 : gfp_t priority)
1101 : {
1102 3778 : return __alloc_skb(size, priority, 0, NUMA_NO_NODE);
1103 : }
1104 :
1105 : struct sk_buff *alloc_skb_with_frags(unsigned long header_len,
1106 : unsigned long data_len,
1107 : int max_page_order,
1108 : int *errcode,
1109 : gfp_t gfp_mask);
1110 : struct sk_buff *alloc_skb_for_msg(struct sk_buff *first);
1111 :
1112 : /* Layout of fast clones : [skb1][skb2][fclone_ref] */
1113 : struct sk_buff_fclones {
1114 : struct sk_buff skb1;
1115 :
1116 : struct sk_buff skb2;
1117 :
1118 : refcount_t fclone_ref;
1119 : };
1120 :
1121 : /**
1122 : * skb_fclone_busy - check if fclone is busy
1123 : * @sk: socket
1124 : * @skb: buffer
1125 : *
1126 : * Returns true if skb is a fast clone, and its clone is not freed.
1127 : * Some drivers call skb_orphan() in their ndo_start_xmit(),
1128 : * so we also check that this didnt happen.
1129 : */
1130 0 : static inline bool skb_fclone_busy(const struct sock *sk,
1131 : const struct sk_buff *skb)
1132 : {
1133 0 : const struct sk_buff_fclones *fclones;
1134 :
1135 0 : fclones = container_of(skb, struct sk_buff_fclones, skb1);
1136 :
1137 0 : return skb->fclone == SKB_FCLONE_ORIG &&
1138 0 : refcount_read(&fclones->fclone_ref) > 1 &&
1139 0 : fclones->skb2.sk == sk;
1140 : }
1141 :
1142 : /**
1143 : * alloc_skb_fclone - allocate a network buffer from fclone cache
1144 : * @size: size to allocate
1145 : * @priority: allocation mask
1146 : *
1147 : * This function is a convenient wrapper around __alloc_skb().
1148 : */
1149 364 : static inline struct sk_buff *alloc_skb_fclone(unsigned int size,
1150 : gfp_t priority)
1151 : {
1152 364 : return __alloc_skb(size, priority, SKB_ALLOC_FCLONE, NUMA_NO_NODE);
1153 : }
1154 :
1155 : struct sk_buff *skb_morph(struct sk_buff *dst, struct sk_buff *src);
1156 : void skb_headers_offset_update(struct sk_buff *skb, int off);
1157 : int skb_copy_ubufs(struct sk_buff *skb, gfp_t gfp_mask);
1158 : struct sk_buff *skb_clone(struct sk_buff *skb, gfp_t priority);
1159 : void skb_copy_header(struct sk_buff *new, const struct sk_buff *old);
1160 : struct sk_buff *skb_copy(const struct sk_buff *skb, gfp_t priority);
1161 : struct sk_buff *__pskb_copy_fclone(struct sk_buff *skb, int headroom,
1162 : gfp_t gfp_mask, bool fclone);
1163 0 : static inline struct sk_buff *__pskb_copy(struct sk_buff *skb, int headroom,
1164 : gfp_t gfp_mask)
1165 : {
1166 0 : return __pskb_copy_fclone(skb, headroom, gfp_mask, false);
1167 : }
1168 :
1169 : int pskb_expand_head(struct sk_buff *skb, int nhead, int ntail, gfp_t gfp_mask);
1170 : struct sk_buff *skb_realloc_headroom(struct sk_buff *skb,
1171 : unsigned int headroom);
1172 : struct sk_buff *skb_copy_expand(const struct sk_buff *skb, int newheadroom,
1173 : int newtailroom, gfp_t priority);
1174 : int __must_check skb_to_sgvec_nomark(struct sk_buff *skb, struct scatterlist *sg,
1175 : int offset, int len);
1176 : int __must_check skb_to_sgvec(struct sk_buff *skb, struct scatterlist *sg,
1177 : int offset, int len);
1178 : int skb_cow_data(struct sk_buff *skb, int tailbits, struct sk_buff **trailer);
1179 : int __skb_pad(struct sk_buff *skb, int pad, bool free_on_error);
1180 :
1181 : /**
1182 : * skb_pad - zero pad the tail of an skb
1183 : * @skb: buffer to pad
1184 : * @pad: space to pad
1185 : *
1186 : * Ensure that a buffer is followed by a padding area that is zero
1187 : * filled. Used by network drivers which may DMA or transfer data
1188 : * beyond the buffer end onto the wire.
1189 : *
1190 : * May return error in out of memory cases. The skb is freed on error.
1191 : */
1192 : static inline int skb_pad(struct sk_buff *skb, int pad)
1193 : {
1194 : return __skb_pad(skb, pad, true);
1195 : }
1196 : #define dev_kfree_skb(a) consume_skb(a)
1197 :
1198 : int skb_append_pagefrags(struct sk_buff *skb, struct page *page,
1199 : int offset, size_t size);
1200 :
1201 : struct skb_seq_state {
1202 : __u32 lower_offset;
1203 : __u32 upper_offset;
1204 : __u32 frag_idx;
1205 : __u32 stepped_offset;
1206 : struct sk_buff *root_skb;
1207 : struct sk_buff *cur_skb;
1208 : __u8 *frag_data;
1209 : __u32 frag_off;
1210 : };
1211 :
1212 : void skb_prepare_seq_read(struct sk_buff *skb, unsigned int from,
1213 : unsigned int to, struct skb_seq_state *st);
1214 : unsigned int skb_seq_read(unsigned int consumed, const u8 **data,
1215 : struct skb_seq_state *st);
1216 : void skb_abort_seq_read(struct skb_seq_state *st);
1217 :
1218 : unsigned int skb_find_text(struct sk_buff *skb, unsigned int from,
1219 : unsigned int to, struct ts_config *config);
1220 :
1221 : /*
1222 : * Packet hash types specify the type of hash in skb_set_hash.
1223 : *
1224 : * Hash types refer to the protocol layer addresses which are used to
1225 : * construct a packet's hash. The hashes are used to differentiate or identify
1226 : * flows of the protocol layer for the hash type. Hash types are either
1227 : * layer-2 (L2), layer-3 (L3), or layer-4 (L4).
1228 : *
1229 : * Properties of hashes:
1230 : *
1231 : * 1) Two packets in different flows have different hash values
1232 : * 2) Two packets in the same flow should have the same hash value
1233 : *
1234 : * A hash at a higher layer is considered to be more specific. A driver should
1235 : * set the most specific hash possible.
1236 : *
1237 : * A driver cannot indicate a more specific hash than the layer at which a hash
1238 : * was computed. For instance an L3 hash cannot be set as an L4 hash.
1239 : *
1240 : * A driver may indicate a hash level which is less specific than the
1241 : * actual layer the hash was computed on. For instance, a hash computed
1242 : * at L4 may be considered an L3 hash. This should only be done if the
1243 : * driver can't unambiguously determine that the HW computed the hash at
1244 : * the higher layer. Note that the "should" in the second property above
1245 : * permits this.
1246 : */
1247 : enum pkt_hash_types {
1248 : PKT_HASH_TYPE_NONE, /* Undefined type */
1249 : PKT_HASH_TYPE_L2, /* Input: src_MAC, dest_MAC */
1250 : PKT_HASH_TYPE_L3, /* Input: src_IP, dst_IP */
1251 : PKT_HASH_TYPE_L4, /* Input: src_IP, dst_IP, src_port, dst_port */
1252 : };
1253 :
1254 0 : static inline void skb_clear_hash(struct sk_buff *skb)
1255 : {
1256 0 : skb->hash = 0;
1257 0 : skb->sw_hash = 0;
1258 0 : skb->l4_hash = 0;
1259 0 : }
1260 :
1261 0 : static inline void skb_clear_hash_if_not_l4(struct sk_buff *skb)
1262 : {
1263 0 : if (!skb->l4_hash)
1264 0 : skb_clear_hash(skb);
1265 : }
1266 :
1267 : static inline void
1268 4 : __skb_set_hash(struct sk_buff *skb, __u32 hash, bool is_sw, bool is_l4)
1269 : {
1270 4 : skb->l4_hash = is_l4;
1271 4 : skb->sw_hash = is_sw;
1272 4 : skb->hash = hash;
1273 : }
1274 :
1275 : static inline void
1276 4 : skb_set_hash(struct sk_buff *skb, __u32 hash, enum pkt_hash_types type)
1277 : {
1278 : /* Used by drivers to set hash from HW */
1279 4 : __skb_set_hash(skb, hash, false, type == PKT_HASH_TYPE_L4);
1280 : }
1281 :
1282 : static inline void
1283 0 : __skb_set_sw_hash(struct sk_buff *skb, __u32 hash, bool is_l4)
1284 : {
1285 0 : __skb_set_hash(skb, hash, true, is_l4);
1286 : }
1287 :
1288 : void __skb_get_hash(struct sk_buff *skb);
1289 : u32 __skb_get_hash_symmetric(const struct sk_buff *skb);
1290 : u32 skb_get_poff(const struct sk_buff *skb);
1291 : u32 __skb_get_poff(const struct sk_buff *skb, void *data,
1292 : const struct flow_keys_basic *keys, int hlen);
1293 : __be32 __skb_flow_get_ports(const struct sk_buff *skb, int thoff, u8 ip_proto,
1294 : void *data, int hlen_proto);
1295 :
1296 : static inline __be32 skb_flow_get_ports(const struct sk_buff *skb,
1297 : int thoff, u8 ip_proto)
1298 : {
1299 : return __skb_flow_get_ports(skb, thoff, ip_proto, NULL, 0);
1300 : }
1301 :
1302 : void skb_flow_dissector_init(struct flow_dissector *flow_dissector,
1303 : const struct flow_dissector_key *key,
1304 : unsigned int key_count);
1305 :
1306 : struct bpf_flow_dissector;
1307 : bool bpf_flow_dissect(struct bpf_prog *prog, struct bpf_flow_dissector *ctx,
1308 : __be16 proto, int nhoff, int hlen, unsigned int flags);
1309 :
1310 : bool __skb_flow_dissect(const struct net *net,
1311 : const struct sk_buff *skb,
1312 : struct flow_dissector *flow_dissector,
1313 : void *target_container,
1314 : void *data, __be16 proto, int nhoff, int hlen,
1315 : unsigned int flags);
1316 :
1317 : static inline bool skb_flow_dissect(const struct sk_buff *skb,
1318 : struct flow_dissector *flow_dissector,
1319 : void *target_container, unsigned int flags)
1320 : {
1321 : return __skb_flow_dissect(NULL, skb, flow_dissector,
1322 : target_container, NULL, 0, 0, 0, flags);
1323 : }
1324 :
1325 0 : static inline bool skb_flow_dissect_flow_keys(const struct sk_buff *skb,
1326 : struct flow_keys *flow,
1327 : unsigned int flags)
1328 : {
1329 0 : memset(flow, 0, sizeof(*flow));
1330 0 : return __skb_flow_dissect(NULL, skb, &flow_keys_dissector,
1331 : flow, NULL, 0, 0, 0, flags);
1332 : }
1333 :
1334 : static inline bool
1335 2 : skb_flow_dissect_flow_keys_basic(const struct net *net,
1336 : const struct sk_buff *skb,
1337 : struct flow_keys_basic *flow, void *data,
1338 : __be16 proto, int nhoff, int hlen,
1339 : unsigned int flags)
1340 : {
1341 2 : memset(flow, 0, sizeof(*flow));
1342 2 : return __skb_flow_dissect(net, skb, &flow_keys_basic_dissector, flow,
1343 : data, proto, nhoff, hlen, flags);
1344 : }
1345 :
1346 : void skb_flow_dissect_meta(const struct sk_buff *skb,
1347 : struct flow_dissector *flow_dissector,
1348 : void *target_container);
1349 :
1350 : /* Gets a skb connection tracking info, ctinfo map should be a
1351 : * map of mapsize to translate enum ip_conntrack_info states
1352 : * to user states.
1353 : */
1354 : void
1355 : skb_flow_dissect_ct(const struct sk_buff *skb,
1356 : struct flow_dissector *flow_dissector,
1357 : void *target_container,
1358 : u16 *ctinfo_map, size_t mapsize,
1359 : bool post_ct);
1360 : void
1361 : skb_flow_dissect_tunnel_info(const struct sk_buff *skb,
1362 : struct flow_dissector *flow_dissector,
1363 : void *target_container);
1364 :
1365 : void skb_flow_dissect_hash(const struct sk_buff *skb,
1366 : struct flow_dissector *flow_dissector,
1367 : void *target_container);
1368 :
1369 0 : static inline __u32 skb_get_hash(struct sk_buff *skb)
1370 : {
1371 0 : if (!skb->l4_hash && !skb->sw_hash)
1372 0 : __skb_get_hash(skb);
1373 :
1374 0 : return skb->hash;
1375 : }
1376 :
1377 : static inline __u32 skb_get_hash_flowi6(struct sk_buff *skb, const struct flowi6 *fl6)
1378 : {
1379 : if (!skb->l4_hash && !skb->sw_hash) {
1380 : struct flow_keys keys;
1381 : __u32 hash = __get_hash_from_flowi6(fl6, &keys);
1382 :
1383 : __skb_set_sw_hash(skb, hash, flow_keys_have_l4(&keys));
1384 : }
1385 :
1386 : return skb->hash;
1387 : }
1388 :
1389 : __u32 skb_get_hash_perturb(const struct sk_buff *skb,
1390 : const siphash_key_t *perturb);
1391 :
1392 1715 : static inline __u32 skb_get_hash_raw(const struct sk_buff *skb)
1393 : {
1394 1715 : return skb->hash;
1395 : }
1396 :
1397 0 : static inline void skb_copy_hash(struct sk_buff *to, const struct sk_buff *from)
1398 : {
1399 0 : to->hash = from->hash;
1400 0 : to->sw_hash = from->sw_hash;
1401 0 : to->l4_hash = from->l4_hash;
1402 : };
1403 :
1404 0 : static inline void skb_copy_decrypted(struct sk_buff *to,
1405 : const struct sk_buff *from)
1406 : {
1407 : #ifdef CONFIG_TLS_DEVICE
1408 : to->decrypted = from->decrypted;
1409 : #endif
1410 0 : }
1411 :
1412 : #ifdef NET_SKBUFF_DATA_USES_OFFSET
1413 44504 : static inline unsigned char *skb_end_pointer(const struct sk_buff *skb)
1414 : {
1415 22359 : return skb->head + skb->end;
1416 : }
1417 :
1418 519 : static inline unsigned int skb_end_offset(const struct sk_buff *skb)
1419 : {
1420 519 : return skb->end;
1421 : }
1422 : #else
1423 : static inline unsigned char *skb_end_pointer(const struct sk_buff *skb)
1424 : {
1425 : return skb->end;
1426 : }
1427 :
1428 : static inline unsigned int skb_end_offset(const struct sk_buff *skb)
1429 : {
1430 : return skb->end - skb->head;
1431 : }
1432 : #endif
1433 :
1434 : /* Internal */
1435 : #define skb_shinfo(SKB) ((struct skb_shared_info *)(skb_end_pointer(SKB)))
1436 :
1437 949 : static inline struct skb_shared_hwtstamps *skb_hwtstamps(struct sk_buff *skb)
1438 : {
1439 949 : return &skb_shinfo(skb)->hwtstamps;
1440 : }
1441 :
1442 9264 : static inline struct ubuf_info *skb_zcopy(struct sk_buff *skb)
1443 : {
1444 9264 : bool is_zcopy = skb && skb_shinfo(skb)->flags & SKBFL_ZEROCOPY_ENABLE;
1445 :
1446 9264 : return is_zcopy ? skb_uarg(skb) : NULL;
1447 : }
1448 :
1449 0 : static inline void net_zcopy_get(struct ubuf_info *uarg)
1450 : {
1451 0 : refcount_inc(&uarg->refcnt);
1452 0 : }
1453 :
1454 0 : static inline void skb_zcopy_init(struct sk_buff *skb, struct ubuf_info *uarg)
1455 : {
1456 0 : skb_shinfo(skb)->destructor_arg = uarg;
1457 0 : skb_shinfo(skb)->flags |= uarg->flags;
1458 0 : }
1459 :
1460 14 : static inline void skb_zcopy_set(struct sk_buff *skb, struct ubuf_info *uarg,
1461 : bool *have_ref)
1462 : {
1463 14 : if (skb && uarg && !skb_zcopy(skb)) {
1464 0 : if (unlikely(have_ref && *have_ref))
1465 0 : *have_ref = false;
1466 : else
1467 0 : net_zcopy_get(uarg);
1468 0 : skb_zcopy_init(skb, uarg);
1469 : }
1470 14 : }
1471 :
1472 0 : static inline void skb_zcopy_set_nouarg(struct sk_buff *skb, void *val)
1473 : {
1474 0 : skb_shinfo(skb)->destructor_arg = (void *)((uintptr_t) val | 0x1UL);
1475 0 : skb_shinfo(skb)->flags |= SKBFL_ZEROCOPY_FRAG;
1476 : }
1477 :
1478 0 : static inline bool skb_zcopy_is_nouarg(struct sk_buff *skb)
1479 : {
1480 0 : return (uintptr_t) skb_shinfo(skb)->destructor_arg & 0x1UL;
1481 : }
1482 :
1483 0 : static inline void *skb_zcopy_get_nouarg(struct sk_buff *skb)
1484 : {
1485 0 : return (void *)((uintptr_t) skb_shinfo(skb)->destructor_arg & ~0x1UL);
1486 : }
1487 :
1488 411 : static inline void net_zcopy_put(struct ubuf_info *uarg)
1489 : {
1490 411 : if (uarg)
1491 0 : uarg->callback(NULL, uarg, true);
1492 411 : }
1493 :
1494 0 : static inline void net_zcopy_put_abort(struct ubuf_info *uarg, bool have_uref)
1495 : {
1496 0 : if (uarg) {
1497 0 : if (uarg->callback == msg_zerocopy_callback)
1498 0 : msg_zerocopy_put_abort(uarg, have_uref);
1499 0 : else if (have_uref)
1500 0 : net_zcopy_put(uarg);
1501 : }
1502 0 : }
1503 :
1504 : /* Release a reference on a zerocopy structure */
1505 5586 : static inline void skb_zcopy_clear(struct sk_buff *skb, bool zerocopy_success)
1506 : {
1507 5586 : struct ubuf_info *uarg = skb_zcopy(skb);
1508 :
1509 5586 : if (uarg) {
1510 0 : if (!skb_zcopy_is_nouarg(skb))
1511 0 : uarg->callback(skb, uarg, zerocopy_success);
1512 :
1513 0 : skb_shinfo(skb)->flags &= ~SKBFL_ZEROCOPY_FRAG;
1514 : }
1515 5586 : }
1516 :
1517 3779 : static inline void skb_mark_not_on_list(struct sk_buff *skb)
1518 : {
1519 2848 : skb->next = NULL;
1520 : }
1521 :
1522 : /* Iterate through singly-linked GSO fragments of an skb. */
1523 : #define skb_list_walk_safe(first, skb, next_skb) \
1524 : for ((skb) = (first), (next_skb) = (skb) ? (skb)->next : NULL; (skb); \
1525 : (skb) = (next_skb), (next_skb) = (skb) ? (skb)->next : NULL)
1526 :
1527 2293 : static inline void skb_list_del_init(struct sk_buff *skb)
1528 : {
1529 2293 : __list_del_entry(&skb->list);
1530 2293 : skb_mark_not_on_list(skb);
1531 : }
1532 :
1533 : /**
1534 : * skb_queue_empty - check if a queue is empty
1535 : * @list: queue head
1536 : *
1537 : * Returns true if the queue is empty, false otherwise.
1538 : */
1539 1149 : static inline int skb_queue_empty(const struct sk_buff_head *list)
1540 : {
1541 1067 : return list->next == (const struct sk_buff *) list;
1542 : }
1543 :
1544 : /**
1545 : * skb_queue_empty_lockless - check if a queue is empty
1546 : * @list: queue head
1547 : *
1548 : * Returns true if the queue is empty, false otherwise.
1549 : * This variant can be used in lockless contexts.
1550 : */
1551 10106 : static inline bool skb_queue_empty_lockless(const struct sk_buff_head *list)
1552 : {
1553 10106 : return READ_ONCE(list->next) == (const struct sk_buff *) list;
1554 : }
1555 :
1556 :
1557 : /**
1558 : * skb_queue_is_last - check if skb is the last entry in the queue
1559 : * @list: queue head
1560 : * @skb: buffer
1561 : *
1562 : * Returns true if @skb is the last buffer on the list.
1563 : */
1564 366 : static inline bool skb_queue_is_last(const struct sk_buff_head *list,
1565 : const struct sk_buff *skb)
1566 : {
1567 366 : return skb->next == (const struct sk_buff *) list;
1568 : }
1569 :
1570 : /**
1571 : * skb_queue_is_first - check if skb is the first entry in the queue
1572 : * @list: queue head
1573 : * @skb: buffer
1574 : *
1575 : * Returns true if @skb is the first buffer on the list.
1576 : */
1577 : static inline bool skb_queue_is_first(const struct sk_buff_head *list,
1578 : const struct sk_buff *skb)
1579 : {
1580 : return skb->prev == (const struct sk_buff *) list;
1581 : }
1582 :
1583 : /**
1584 : * skb_queue_next - return the next packet in the queue
1585 : * @list: queue head
1586 : * @skb: current buffer
1587 : *
1588 : * Return the next packet in @list after @skb. It is only valid to
1589 : * call this if skb_queue_is_last() evaluates to false.
1590 : */
1591 : static inline struct sk_buff *skb_queue_next(const struct sk_buff_head *list,
1592 : const struct sk_buff *skb)
1593 : {
1594 : /* This BUG_ON may seem severe, but if we just return then we
1595 : * are going to dereference garbage.
1596 : */
1597 : BUG_ON(skb_queue_is_last(list, skb));
1598 : return skb->next;
1599 : }
1600 :
1601 : /**
1602 : * skb_queue_prev - return the prev packet in the queue
1603 : * @list: queue head
1604 : * @skb: current buffer
1605 : *
1606 : * Return the prev packet in @list before @skb. It is only valid to
1607 : * call this if skb_queue_is_first() evaluates to false.
1608 : */
1609 : static inline struct sk_buff *skb_queue_prev(const struct sk_buff_head *list,
1610 : const struct sk_buff *skb)
1611 : {
1612 : /* This BUG_ON may seem severe, but if we just return then we
1613 : * are going to dereference garbage.
1614 : */
1615 : BUG_ON(skb_queue_is_first(list, skb));
1616 : return skb->prev;
1617 : }
1618 :
1619 : /**
1620 : * skb_get - reference buffer
1621 : * @skb: buffer to reference
1622 : *
1623 : * Makes another reference to a socket buffer and returns a pointer
1624 : * to the buffer.
1625 : */
1626 3002 : static inline struct sk_buff *skb_get(struct sk_buff *skb)
1627 : {
1628 3002 : refcount_inc(&skb->users);
1629 3001 : return skb;
1630 : }
1631 :
1632 : /*
1633 : * If users == 1, we are the only owner and can avoid redundant atomic changes.
1634 : */
1635 :
1636 : /**
1637 : * skb_cloned - is the buffer a clone
1638 : * @skb: buffer to check
1639 : *
1640 : * Returns true if the buffer was generated with skb_clone() and is
1641 : * one of multiple shared copies of the buffer. Cloned buffers are
1642 : * shared data so must not be written to under normal circumstances.
1643 : */
1644 1200 : static inline int skb_cloned(const struct sk_buff *skb)
1645 : {
1646 1200 : return skb->cloned &&
1647 365 : (atomic_read(&skb_shinfo(skb)->dataref) & SKB_DATAREF_MASK) != 1;
1648 : }
1649 :
1650 0 : static inline int skb_unclone(struct sk_buff *skb, gfp_t pri)
1651 : {
1652 0 : might_sleep_if(gfpflags_allow_blocking(pri));
1653 :
1654 0 : if (skb_cloned(skb))
1655 0 : return pskb_expand_head(skb, 0, 0, pri);
1656 :
1657 : return 0;
1658 : }
1659 :
1660 : /**
1661 : * skb_header_cloned - is the header a clone
1662 : * @skb: buffer to check
1663 : *
1664 : * Returns true if modifying the header part of the buffer requires
1665 : * the data to be copied.
1666 : */
1667 451 : static inline int skb_header_cloned(const struct sk_buff *skb)
1668 : {
1669 451 : int dataref;
1670 :
1671 451 : if (!skb->cloned)
1672 : return 0;
1673 :
1674 449 : dataref = atomic_read(&skb_shinfo(skb)->dataref);
1675 449 : dataref = (dataref & SKB_DATAREF_MASK) - (dataref >> SKB_DATAREF_SHIFT);
1676 449 : return dataref != 1;
1677 : }
1678 :
1679 0 : static inline int skb_header_unclone(struct sk_buff *skb, gfp_t pri)
1680 : {
1681 0 : might_sleep_if(gfpflags_allow_blocking(pri));
1682 :
1683 0 : if (skb_header_cloned(skb))
1684 0 : return pskb_expand_head(skb, 0, 0, pri);
1685 :
1686 : return 0;
1687 : }
1688 :
1689 : /**
1690 : * __skb_header_release - release reference to header
1691 : * @skb: buffer to operate on
1692 : */
1693 631 : static inline void __skb_header_release(struct sk_buff *skb)
1694 : {
1695 631 : skb->nohdr = 1;
1696 631 : atomic_set(&skb_shinfo(skb)->dataref, 1 + (1 << SKB_DATAREF_SHIFT));
1697 631 : }
1698 :
1699 :
1700 : /**
1701 : * skb_shared - is the buffer shared
1702 : * @skb: buffer to check
1703 : *
1704 : * Returns true if more than one person has a reference to this
1705 : * buffer.
1706 : */
1707 1691 : static inline int skb_shared(const struct sk_buff *skb)
1708 : {
1709 2149 : return refcount_read(&skb->users) != 1;
1710 : }
1711 :
1712 : /**
1713 : * skb_share_check - check if buffer is shared and if so clone it
1714 : * @skb: buffer to check
1715 : * @pri: priority for memory allocation
1716 : *
1717 : * If the buffer is shared the buffer is cloned and the old copy
1718 : * drops a reference. A new clone with a single reference is returned.
1719 : * If the buffer is not shared the original buffer is returned. When
1720 : * being called from interrupt status or with spinlocks held pri must
1721 : * be GFP_ATOMIC.
1722 : *
1723 : * NULL is returned on a memory allocation failure.
1724 : */
1725 458 : static inline struct sk_buff *skb_share_check(struct sk_buff *skb, gfp_t pri)
1726 : {
1727 458 : might_sleep_if(gfpflags_allow_blocking(pri));
1728 458 : if (skb_shared(skb)) {
1729 0 : struct sk_buff *nskb = skb_clone(skb, pri);
1730 :
1731 0 : if (likely(nskb))
1732 0 : consume_skb(skb);
1733 : else
1734 0 : kfree_skb(skb);
1735 : skb = nskb;
1736 : }
1737 458 : return skb;
1738 : }
1739 :
1740 : /*
1741 : * Copy shared buffers into a new sk_buff. We effectively do COW on
1742 : * packets to handle cases where we have a local reader and forward
1743 : * and a couple of other messy ones. The normal one is tcpdumping
1744 : * a packet thats being forwarded.
1745 : */
1746 :
1747 : /**
1748 : * skb_unshare - make a copy of a shared buffer
1749 : * @skb: buffer to check
1750 : * @pri: priority for memory allocation
1751 : *
1752 : * If the socket buffer is a clone then this function creates a new
1753 : * copy of the data, drops a reference count on the old copy and returns
1754 : * the new copy with the reference count at 1. If the buffer is not a clone
1755 : * the original buffer is returned. When called with a spinlock held or
1756 : * from interrupt state @pri must be %GFP_ATOMIC
1757 : *
1758 : * %NULL is returned on a memory allocation failure.
1759 : */
1760 : static inline struct sk_buff *skb_unshare(struct sk_buff *skb,
1761 : gfp_t pri)
1762 : {
1763 : might_sleep_if(gfpflags_allow_blocking(pri));
1764 : if (skb_cloned(skb)) {
1765 : struct sk_buff *nskb = skb_copy(skb, pri);
1766 :
1767 : /* Free our shared copy */
1768 : if (likely(nskb))
1769 : consume_skb(skb);
1770 : else
1771 : kfree_skb(skb);
1772 : skb = nskb;
1773 : }
1774 : return skb;
1775 : }
1776 :
1777 : /**
1778 : * skb_peek - peek at the head of an &sk_buff_head
1779 : * @list_: list to peek at
1780 : *
1781 : * Peek an &sk_buff. Unlike most other operations you _MUST_
1782 : * be careful with this one. A peek leaves the buffer on the
1783 : * list and someone else may run off with it. You must hold
1784 : * the appropriate locks or have a private queue to do this.
1785 : *
1786 : * Returns %NULL for an empty list or a pointer to the head element.
1787 : * The reference count is not incremented and the reference is therefore
1788 : * volatile. Use with caution.
1789 : */
1790 8251 : static inline struct sk_buff *skb_peek(const struct sk_buff_head *list_)
1791 : {
1792 8251 : struct sk_buff *skb = list_->next;
1793 :
1794 6785 : if (skb == (struct sk_buff *)list_)
1795 896 : skb = NULL;
1796 4498 : return skb;
1797 : }
1798 :
1799 : /**
1800 : * __skb_peek - peek at the head of a non-empty &sk_buff_head
1801 : * @list_: list to peek at
1802 : *
1803 : * Like skb_peek(), but the caller knows that the list is not empty.
1804 : */
1805 : static inline struct sk_buff *__skb_peek(const struct sk_buff_head *list_)
1806 : {
1807 : return list_->next;
1808 : }
1809 :
1810 : /**
1811 : * skb_peek_next - peek skb following the given one from a queue
1812 : * @skb: skb to start from
1813 : * @list_: list to peek at
1814 : *
1815 : * Returns %NULL when the end of the list is met or a pointer to the
1816 : * next element. The reference count is not incremented and the
1817 : * reference is therefore volatile. Use with caution.
1818 : */
1819 0 : static inline struct sk_buff *skb_peek_next(struct sk_buff *skb,
1820 : const struct sk_buff_head *list_)
1821 : {
1822 0 : struct sk_buff *next = skb->next;
1823 :
1824 0 : if (next == (struct sk_buff *)list_)
1825 : next = NULL;
1826 0 : return next;
1827 : }
1828 :
1829 : /**
1830 : * skb_peek_tail - peek at the tail of an &sk_buff_head
1831 : * @list_: list to peek at
1832 : *
1833 : * Peek an &sk_buff. Unlike most other operations you _MUST_
1834 : * be careful with this one. A peek leaves the buffer on the
1835 : * list and someone else may run off with it. You must hold
1836 : * the appropriate locks or have a private queue to do this.
1837 : *
1838 : * Returns %NULL for an empty list or a pointer to the tail element.
1839 : * The reference count is not incremented and the reference is therefore
1840 : * volatile. Use with caution.
1841 : */
1842 1700 : static inline struct sk_buff *skb_peek_tail(const struct sk_buff_head *list_)
1843 : {
1844 1700 : struct sk_buff *skb = READ_ONCE(list_->prev);
1845 :
1846 1700 : if (skb == (struct sk_buff *)list_)
1847 130 : skb = NULL;
1848 1267 : return skb;
1849 :
1850 : }
1851 :
1852 : /**
1853 : * skb_queue_len - get queue length
1854 : * @list_: list to measure
1855 : *
1856 : * Return the length of an &sk_buff queue.
1857 : */
1858 195 : static inline __u32 skb_queue_len(const struct sk_buff_head *list_)
1859 : {
1860 195 : return list_->qlen;
1861 : }
1862 :
1863 : /**
1864 : * skb_queue_len_lockless - get queue length
1865 : * @list_: list to measure
1866 : *
1867 : * Return the length of an &sk_buff queue.
1868 : * This variant can be used in lockless contexts.
1869 : */
1870 599 : static inline __u32 skb_queue_len_lockless(const struct sk_buff_head *list_)
1871 : {
1872 599 : return READ_ONCE(list_->qlen);
1873 : }
1874 :
1875 : /**
1876 : * __skb_queue_head_init - initialize non-spinlock portions of sk_buff_head
1877 : * @list: queue to initialize
1878 : *
1879 : * This initializes only the list and queue length aspects of
1880 : * an sk_buff_head object. This allows to initialize the list
1881 : * aspects of an sk_buff_head without reinitializing things like
1882 : * the spinlock. It can also be used for on-stack sk_buff_head
1883 : * objects where the spinlock is known to not be used.
1884 : */
1885 2637 : static inline void __skb_queue_head_init(struct sk_buff_head *list)
1886 : {
1887 2637 : list->prev = list->next = (struct sk_buff *)list;
1888 2636 : list->qlen = 0;
1889 2 : }
1890 :
1891 : /*
1892 : * This function creates a split out lock class for each invocation;
1893 : * this is needed for now since a whole lot of users of the skb-queue
1894 : * infrastructure in drivers have different locking usage (in hardirq)
1895 : * than the networking core (in softirq only). In the long run either the
1896 : * network layer or drivers should need annotation to consolidate the
1897 : * main types of usage into 3 classes.
1898 : */
1899 2616 : static inline void skb_queue_head_init(struct sk_buff_head *list)
1900 : {
1901 2616 : spin_lock_init(&list->lock);
1902 2616 : __skb_queue_head_init(list);
1903 2616 : }
1904 :
1905 1 : static inline void skb_queue_head_init_class(struct sk_buff_head *list,
1906 : struct lock_class_key *class)
1907 : {
1908 1 : skb_queue_head_init(list);
1909 1 : lockdep_set_class(&list->lock, class);
1910 1 : }
1911 :
1912 : /*
1913 : * Insert an sk_buff on a list.
1914 : *
1915 : * The "__skb_xxxx()" functions are the non-atomic ones that
1916 : * can only be called with interrupts disabled.
1917 : */
1918 3704 : static inline void __skb_insert(struct sk_buff *newsk,
1919 : struct sk_buff *prev, struct sk_buff *next,
1920 : struct sk_buff_head *list)
1921 : {
1922 : /* See skb_queue_empty_lockless() and skb_peek_tail()
1923 : * for the opposite READ_ONCE()
1924 : */
1925 3704 : WRITE_ONCE(newsk->next, next);
1926 3704 : WRITE_ONCE(newsk->prev, prev);
1927 3704 : WRITE_ONCE(next->prev, newsk);
1928 3704 : WRITE_ONCE(prev->next, newsk);
1929 3704 : list->qlen++;
1930 : }
1931 :
1932 2 : static inline void __skb_queue_splice(const struct sk_buff_head *list,
1933 : struct sk_buff *prev,
1934 : struct sk_buff *next)
1935 : {
1936 2 : struct sk_buff *first = list->next;
1937 2 : struct sk_buff *last = list->prev;
1938 :
1939 2 : WRITE_ONCE(first->prev, prev);
1940 2 : WRITE_ONCE(prev->next, first);
1941 :
1942 2 : WRITE_ONCE(last->next, next);
1943 2 : WRITE_ONCE(next->prev, last);
1944 : }
1945 :
1946 : /**
1947 : * skb_queue_splice - join two skb lists, this is designed for stacks
1948 : * @list: the new list to add
1949 : * @head: the place to add it in the first list
1950 : */
1951 : static inline void skb_queue_splice(const struct sk_buff_head *list,
1952 : struct sk_buff_head *head)
1953 : {
1954 : if (!skb_queue_empty(list)) {
1955 : __skb_queue_splice(list, (struct sk_buff *) head, head->next);
1956 : head->qlen += list->qlen;
1957 : }
1958 : }
1959 :
1960 : /**
1961 : * skb_queue_splice_init - join two skb lists and reinitialise the emptied list
1962 : * @list: the new list to add
1963 : * @head: the place to add it in the first list
1964 : *
1965 : * The list at @list is reinitialised
1966 : */
1967 : static inline void skb_queue_splice_init(struct sk_buff_head *list,
1968 : struct sk_buff_head *head)
1969 : {
1970 : if (!skb_queue_empty(list)) {
1971 : __skb_queue_splice(list, (struct sk_buff *) head, head->next);
1972 : head->qlen += list->qlen;
1973 : __skb_queue_head_init(list);
1974 : }
1975 : }
1976 :
1977 : /**
1978 : * skb_queue_splice_tail - join two skb lists, each list being a queue
1979 : * @list: the new list to add
1980 : * @head: the place to add it in the first list
1981 : */
1982 : static inline void skb_queue_splice_tail(const struct sk_buff_head *list,
1983 : struct sk_buff_head *head)
1984 : {
1985 : if (!skb_queue_empty(list)) {
1986 : __skb_queue_splice(list, head->prev, (struct sk_buff *) head);
1987 : head->qlen += list->qlen;
1988 : }
1989 : }
1990 :
1991 : /**
1992 : * skb_queue_splice_tail_init - join two skb lists and reinitialise the emptied list
1993 : * @list: the new list to add
1994 : * @head: the place to add it in the first list
1995 : *
1996 : * Each of the lists is a queue.
1997 : * The list at @list is reinitialised
1998 : */
1999 82 : static inline void skb_queue_splice_tail_init(struct sk_buff_head *list,
2000 : struct sk_buff_head *head)
2001 : {
2002 82 : if (!skb_queue_empty(list)) {
2003 2 : __skb_queue_splice(list, head->prev, (struct sk_buff *) head);
2004 2 : head->qlen += list->qlen;
2005 2 : __skb_queue_head_init(list);
2006 : }
2007 82 : }
2008 :
2009 : /**
2010 : * __skb_queue_after - queue a buffer at the list head
2011 : * @list: list to use
2012 : * @prev: place after this buffer
2013 : * @newsk: buffer to queue
2014 : *
2015 : * Queue a buffer int the middle of a list. This function takes no locks
2016 : * and you must therefore hold required locks before calling it.
2017 : *
2018 : * A buffer cannot be placed on two lists at the same time.
2019 : */
2020 0 : static inline void __skb_queue_after(struct sk_buff_head *list,
2021 : struct sk_buff *prev,
2022 : struct sk_buff *newsk)
2023 : {
2024 0 : __skb_insert(newsk, prev, prev->next, list);
2025 0 : }
2026 :
2027 : void skb_append(struct sk_buff *old, struct sk_buff *newsk,
2028 : struct sk_buff_head *list);
2029 :
2030 3704 : static inline void __skb_queue_before(struct sk_buff_head *list,
2031 : struct sk_buff *next,
2032 : struct sk_buff *newsk)
2033 : {
2034 3701 : __skb_insert(newsk, next->prev, next, list);
2035 0 : }
2036 :
2037 : /**
2038 : * __skb_queue_head - queue a buffer at the list head
2039 : * @list: list to use
2040 : * @newsk: buffer to queue
2041 : *
2042 : * Queue a buffer at the start of a list. This function takes no locks
2043 : * and you must therefore hold required locks before calling it.
2044 : *
2045 : * A buffer cannot be placed on two lists at the same time.
2046 : */
2047 0 : static inline void __skb_queue_head(struct sk_buff_head *list,
2048 : struct sk_buff *newsk)
2049 : {
2050 0 : __skb_queue_after(list, (struct sk_buff *)list, newsk);
2051 : }
2052 : void skb_queue_head(struct sk_buff_head *list, struct sk_buff *newsk);
2053 :
2054 : /**
2055 : * __skb_queue_tail - queue a buffer at the list tail
2056 : * @list: list to use
2057 : * @newsk: buffer to queue
2058 : *
2059 : * Queue a buffer at the end of a list. This function takes no locks
2060 : * and you must therefore hold required locks before calling it.
2061 : *
2062 : * A buffer cannot be placed on two lists at the same time.
2063 : */
2064 3704 : static inline void __skb_queue_tail(struct sk_buff_head *list,
2065 : struct sk_buff *newsk)
2066 : {
2067 3704 : __skb_queue_before(list, (struct sk_buff *)list, newsk);
2068 0 : }
2069 : void skb_queue_tail(struct sk_buff_head *list, struct sk_buff *newsk);
2070 :
2071 : /*
2072 : * remove sk_buff from list. _Must_ be called atomically, and with
2073 : * the list known..
2074 : */
2075 : void skb_unlink(struct sk_buff *skb, struct sk_buff_head *list);
2076 3704 : static inline void __skb_unlink(struct sk_buff *skb, struct sk_buff_head *list)
2077 : {
2078 3704 : struct sk_buff *next, *prev;
2079 :
2080 3704 : WRITE_ONCE(list->qlen, list->qlen - 1);
2081 3704 : next = skb->next;
2082 3704 : prev = skb->prev;
2083 3704 : skb->next = skb->prev = NULL;
2084 3704 : WRITE_ONCE(next->prev, prev);
2085 2339 : WRITE_ONCE(prev->next, next);
2086 1379 : }
2087 :
2088 : /**
2089 : * __skb_dequeue - remove from the head of the queue
2090 : * @list: list to dequeue from
2091 : *
2092 : * Remove the head of the list. This function does not take any locks
2093 : * so must be used with appropriate locks held only. The head item is
2094 : * returned or %NULL if the list is empty.
2095 : */
2096 1620 : static inline struct sk_buff *__skb_dequeue(struct sk_buff_head *list)
2097 : {
2098 1620 : struct sk_buff *skb = skb_peek(list);
2099 17 : if (skb)
2100 17 : __skb_unlink(skb, list);
2101 1620 : return skb;
2102 : }
2103 : struct sk_buff *skb_dequeue(struct sk_buff_head *list);
2104 :
2105 : /**
2106 : * __skb_dequeue_tail - remove from the tail of the queue
2107 : * @list: list to dequeue from
2108 : *
2109 : * Remove the tail of the list. This function does not take any locks
2110 : * so must be used with appropriate locks held only. The tail item is
2111 : * returned or %NULL if the list is empty.
2112 : */
2113 0 : static inline struct sk_buff *__skb_dequeue_tail(struct sk_buff_head *list)
2114 : {
2115 0 : struct sk_buff *skb = skb_peek_tail(list);
2116 0 : if (skb)
2117 0 : __skb_unlink(skb, list);
2118 0 : return skb;
2119 : }
2120 : struct sk_buff *skb_dequeue_tail(struct sk_buff_head *list);
2121 :
2122 :
2123 8352 : static inline bool skb_is_nonlinear(const struct sk_buff *skb)
2124 : {
2125 7426 : return skb->data_len;
2126 : }
2127 :
2128 16736 : static inline unsigned int skb_headlen(const struct sk_buff *skb)
2129 : {
2130 15945 : return skb->len - skb->data_len;
2131 : }
2132 :
2133 0 : static inline unsigned int __skb_pagelen(const struct sk_buff *skb)
2134 : {
2135 0 : unsigned int i, len = 0;
2136 :
2137 0 : for (i = skb_shinfo(skb)->nr_frags - 1; (int)i >= 0; i--)
2138 0 : len += skb_frag_size(&skb_shinfo(skb)->frags[i]);
2139 0 : return len;
2140 : }
2141 :
2142 0 : static inline unsigned int skb_pagelen(const struct sk_buff *skb)
2143 : {
2144 0 : return skb_headlen(skb) + __skb_pagelen(skb);
2145 : }
2146 :
2147 : /**
2148 : * __skb_fill_page_desc - initialise a paged fragment in an skb
2149 : * @skb: buffer containing fragment to be initialised
2150 : * @i: paged fragment index to initialise
2151 : * @page: the page to use for this fragment
2152 : * @off: the offset to the data with @page
2153 : * @size: the length of the data
2154 : *
2155 : * Initialises the @i'th fragment of @skb to point to &size bytes at
2156 : * offset @off within @page.
2157 : *
2158 : * Does not take any additional reference on the fragment.
2159 : */
2160 691 : static inline void __skb_fill_page_desc(struct sk_buff *skb, int i,
2161 : struct page *page, int off, int size)
2162 : {
2163 691 : skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
2164 :
2165 : /*
2166 : * Propagate page pfmemalloc to the skb if we can. The problem is
2167 : * that not all callers have unique ownership of the page but rely
2168 : * on page_is_pfmemalloc doing the right thing(tm).
2169 : */
2170 691 : frag->bv_page = page;
2171 691 : frag->bv_offset = off;
2172 691 : skb_frag_size_set(frag, size);
2173 :
2174 691 : page = compound_head(page);
2175 691 : if (page_is_pfmemalloc(page))
2176 0 : skb->pfmemalloc = true;
2177 691 : }
2178 :
2179 : /**
2180 : * skb_fill_page_desc - initialise a paged fragment in an skb
2181 : * @skb: buffer containing fragment to be initialised
2182 : * @i: paged fragment index to initialise
2183 : * @page: the page to use for this fragment
2184 : * @off: the offset to the data with @page
2185 : * @size: the length of the data
2186 : *
2187 : * As per __skb_fill_page_desc() -- initialises the @i'th fragment of
2188 : * @skb to point to @size bytes at offset @off within @page. In
2189 : * addition updates @skb such that @i is the last fragment.
2190 : *
2191 : * Does not take any additional reference on the fragment.
2192 : */
2193 691 : static inline void skb_fill_page_desc(struct sk_buff *skb, int i,
2194 : struct page *page, int off, int size)
2195 : {
2196 691 : __skb_fill_page_desc(skb, i, page, off, size);
2197 691 : skb_shinfo(skb)->nr_frags = i + 1;
2198 691 : }
2199 :
2200 : void skb_add_rx_frag(struct sk_buff *skb, int i, struct page *page, int off,
2201 : int size, unsigned int truesize);
2202 :
2203 : void skb_coalesce_rx_frag(struct sk_buff *skb, int i, int size,
2204 : unsigned int truesize);
2205 :
2206 : #define SKB_LINEAR_ASSERT(skb) BUG_ON(skb_is_nonlinear(skb))
2207 :
2208 : #ifdef NET_SKBUFF_DATA_USES_OFFSET
2209 6972 : static inline unsigned char *skb_tail_pointer(const struct sk_buff *skb)
2210 : {
2211 6972 : return skb->head + skb->tail;
2212 : }
2213 :
2214 4880 : static inline void skb_reset_tail_pointer(struct sk_buff *skb)
2215 : {
2216 4864 : skb->tail = skb->data - skb->head;
2217 : }
2218 :
2219 16 : static inline void skb_set_tail_pointer(struct sk_buff *skb, const int offset)
2220 : {
2221 16 : skb_reset_tail_pointer(skb);
2222 0 : skb->tail += offset;
2223 0 : }
2224 :
2225 : #else /* NET_SKBUFF_DATA_USES_OFFSET */
2226 : static inline unsigned char *skb_tail_pointer(const struct sk_buff *skb)
2227 : {
2228 : return skb->tail;
2229 : }
2230 :
2231 : static inline void skb_reset_tail_pointer(struct sk_buff *skb)
2232 : {
2233 : skb->tail = skb->data;
2234 : }
2235 :
2236 : static inline void skb_set_tail_pointer(struct sk_buff *skb, const int offset)
2237 : {
2238 : skb->tail = skb->data + offset;
2239 : }
2240 :
2241 : #endif /* NET_SKBUFF_DATA_USES_OFFSET */
2242 :
2243 : /*
2244 : * Add data to an sk_buff
2245 : */
2246 : void *pskb_put(struct sk_buff *skb, struct sk_buff *tail, int len);
2247 : void *skb_put(struct sk_buff *skb, unsigned int len);
2248 0 : static inline void *__skb_put(struct sk_buff *skb, unsigned int len)
2249 : {
2250 0 : void *tmp = skb_tail_pointer(skb);
2251 0 : SKB_LINEAR_ASSERT(skb);
2252 0 : skb->tail += len;
2253 0 : skb->len += len;
2254 0 : return tmp;
2255 : }
2256 :
2257 : static inline void *__skb_put_zero(struct sk_buff *skb, unsigned int len)
2258 : {
2259 : void *tmp = __skb_put(skb, len);
2260 :
2261 : memset(tmp, 0, len);
2262 : return tmp;
2263 : }
2264 :
2265 : static inline void *__skb_put_data(struct sk_buff *skb, const void *data,
2266 : unsigned int len)
2267 : {
2268 : void *tmp = __skb_put(skb, len);
2269 :
2270 : memcpy(tmp, data, len);
2271 : return tmp;
2272 : }
2273 :
2274 : static inline void __skb_put_u8(struct sk_buff *skb, u8 val)
2275 : {
2276 : *(u8 *)__skb_put(skb, 1) = val;
2277 : }
2278 :
2279 0 : static inline void *skb_put_zero(struct sk_buff *skb, unsigned int len)
2280 : {
2281 0 : void *tmp = skb_put(skb, len);
2282 :
2283 0 : memset(tmp, 0, len);
2284 :
2285 0 : return tmp;
2286 : }
2287 :
2288 915 : static inline void *skb_put_data(struct sk_buff *skb, const void *data,
2289 : unsigned int len)
2290 : {
2291 915 : void *tmp = skb_put(skb, len);
2292 :
2293 915 : memcpy(tmp, data, len);
2294 :
2295 915 : return tmp;
2296 : }
2297 :
2298 : static inline void skb_put_u8(struct sk_buff *skb, u8 val)
2299 : {
2300 : *(u8 *)skb_put(skb, 1) = val;
2301 : }
2302 :
2303 : void *skb_push(struct sk_buff *skb, unsigned int len);
2304 886 : static inline void *__skb_push(struct sk_buff *skb, unsigned int len)
2305 : {
2306 886 : skb->data -= len;
2307 886 : skb->len += len;
2308 886 : return skb->data;
2309 : }
2310 :
2311 : void *skb_pull(struct sk_buff *skb, unsigned int len);
2312 2029 : static inline void *__skb_pull(struct sk_buff *skb, unsigned int len)
2313 : {
2314 2029 : skb->len -= len;
2315 2029 : BUG_ON(skb->len < skb->data_len);
2316 2029 : return skb->data += len;
2317 : }
2318 :
2319 766 : static inline void *skb_pull_inline(struct sk_buff *skb, unsigned int len)
2320 : {
2321 766 : return unlikely(len > skb->len) ? NULL : __skb_pull(skb, len);
2322 : }
2323 :
2324 : void *__pskb_pull_tail(struct sk_buff *skb, int delta);
2325 :
2326 14 : static inline void *__pskb_pull(struct sk_buff *skb, unsigned int len)
2327 : {
2328 14 : if (len > skb_headlen(skb) &&
2329 0 : !__pskb_pull_tail(skb, len - skb_headlen(skb)))
2330 : return NULL;
2331 14 : skb->len -= len;
2332 14 : return skb->data += len;
2333 : }
2334 :
2335 14 : static inline void *pskb_pull(struct sk_buff *skb, unsigned int len)
2336 : {
2337 14 : return unlikely(len > skb->len) ? NULL : __pskb_pull(skb, len);
2338 : }
2339 :
2340 4772 : static inline bool pskb_may_pull(struct sk_buff *skb, unsigned int len)
2341 : {
2342 4772 : if (likely(len <= skb_headlen(skb)))
2343 : return true;
2344 0 : if (unlikely(len > skb->len))
2345 : return false;
2346 0 : return __pskb_pull_tail(skb, len - skb_headlen(skb)) != NULL;
2347 : }
2348 :
2349 : void skb_condense(struct sk_buff *skb);
2350 :
2351 : /**
2352 : * skb_headroom - bytes at buffer head
2353 : * @skb: buffer to check
2354 : *
2355 : * Return the number of bytes of free space at the head of an &sk_buff.
2356 : */
2357 3008 : static inline unsigned int skb_headroom(const struct sk_buff *skb)
2358 : {
2359 2145 : return skb->data - skb->head;
2360 : }
2361 :
2362 : /**
2363 : * skb_tailroom - bytes at buffer end
2364 : * @skb: buffer to check
2365 : *
2366 : * Return the number of bytes of free space at the tail of an sk_buff
2367 : */
2368 1833 : static inline int skb_tailroom(const struct sk_buff *skb)
2369 : {
2370 1833 : return skb_is_nonlinear(skb) ? 0 : skb->end - skb->tail;
2371 : }
2372 :
2373 : /**
2374 : * skb_availroom - bytes at buffer end
2375 : * @skb: buffer to check
2376 : *
2377 : * Return the number of bytes of free space at the tail of an sk_buff
2378 : * allocated by sk_stream_alloc()
2379 : */
2380 411 : static inline int skb_availroom(const struct sk_buff *skb)
2381 : {
2382 411 : if (skb_is_nonlinear(skb))
2383 : return 0;
2384 :
2385 361 : return skb->end - skb->tail - skb->reserved_tailroom;
2386 : }
2387 :
2388 : /**
2389 : * skb_reserve - adjust headroom
2390 : * @skb: buffer to alter
2391 : * @len: bytes to move
2392 : *
2393 : * Increase the headroom of an empty &sk_buff by reducing the tail
2394 : * room. This is only allowed for an empty buffer.
2395 : */
2396 1241 : static inline void skb_reserve(struct sk_buff *skb, int len)
2397 : {
2398 1241 : skb->data += len;
2399 1241 : skb->tail += len;
2400 : }
2401 :
2402 : /**
2403 : * skb_tailroom_reserve - adjust reserved_tailroom
2404 : * @skb: buffer to alter
2405 : * @mtu: maximum amount of headlen permitted
2406 : * @needed_tailroom: minimum amount of reserved_tailroom
2407 : *
2408 : * Set reserved_tailroom so that headlen can be as large as possible but
2409 : * not larger than mtu and tailroom cannot be smaller than
2410 : * needed_tailroom.
2411 : * The required headroom should already have been reserved before using
2412 : * this function.
2413 : */
2414 : static inline void skb_tailroom_reserve(struct sk_buff *skb, unsigned int mtu,
2415 : unsigned int needed_tailroom)
2416 : {
2417 : SKB_LINEAR_ASSERT(skb);
2418 : if (mtu < skb_tailroom(skb) - needed_tailroom)
2419 : /* use at most mtu */
2420 : skb->reserved_tailroom = skb_tailroom(skb) - mtu;
2421 : else
2422 : /* use up to all available space */
2423 : skb->reserved_tailroom = needed_tailroom;
2424 : }
2425 :
2426 : #define ENCAP_TYPE_ETHER 0
2427 : #define ENCAP_TYPE_IPPROTO 1
2428 :
2429 0 : static inline void skb_set_inner_protocol(struct sk_buff *skb,
2430 : __be16 protocol)
2431 : {
2432 0 : skb->inner_protocol = protocol;
2433 0 : skb->inner_protocol_type = ENCAP_TYPE_ETHER;
2434 0 : }
2435 :
2436 : static inline void skb_set_inner_ipproto(struct sk_buff *skb,
2437 : __u8 ipproto)
2438 : {
2439 : skb->inner_ipproto = ipproto;
2440 : skb->inner_protocol_type = ENCAP_TYPE_IPPROTO;
2441 : }
2442 :
2443 0 : static inline void skb_reset_inner_headers(struct sk_buff *skb)
2444 : {
2445 0 : skb->inner_mac_header = skb->mac_header;
2446 0 : skb->inner_network_header = skb->network_header;
2447 0 : skb->inner_transport_header = skb->transport_header;
2448 0 : }
2449 :
2450 1176 : static inline void skb_reset_mac_len(struct sk_buff *skb)
2451 : {
2452 1176 : skb->mac_len = skb->network_header - skb->mac_header;
2453 0 : }
2454 :
2455 0 : static inline unsigned char *skb_inner_transport_header(const struct sk_buff
2456 : *skb)
2457 : {
2458 0 : return skb->head + skb->inner_transport_header;
2459 : }
2460 :
2461 0 : static inline int skb_inner_transport_offset(const struct sk_buff *skb)
2462 : {
2463 0 : return skb_inner_transport_header(skb) - skb->data;
2464 : }
2465 :
2466 0 : static inline void skb_reset_inner_transport_header(struct sk_buff *skb)
2467 : {
2468 0 : skb->inner_transport_header = skb->data - skb->head;
2469 : }
2470 :
2471 0 : static inline void skb_set_inner_transport_header(struct sk_buff *skb,
2472 : const int offset)
2473 : {
2474 0 : skb_reset_inner_transport_header(skb);
2475 0 : skb->inner_transport_header += offset;
2476 0 : }
2477 :
2478 0 : static inline unsigned char *skb_inner_network_header(const struct sk_buff *skb)
2479 : {
2480 0 : return skb->head + skb->inner_network_header;
2481 : }
2482 :
2483 0 : static inline void skb_reset_inner_network_header(struct sk_buff *skb)
2484 : {
2485 0 : skb->inner_network_header = skb->data - skb->head;
2486 : }
2487 :
2488 0 : static inline void skb_set_inner_network_header(struct sk_buff *skb,
2489 : const int offset)
2490 : {
2491 0 : skb_reset_inner_network_header(skb);
2492 0 : skb->inner_network_header += offset;
2493 0 : }
2494 :
2495 0 : static inline unsigned char *skb_inner_mac_header(const struct sk_buff *skb)
2496 : {
2497 0 : return skb->head + skb->inner_mac_header;
2498 : }
2499 :
2500 0 : static inline void skb_reset_inner_mac_header(struct sk_buff *skb)
2501 : {
2502 0 : skb->inner_mac_header = skb->data - skb->head;
2503 : }
2504 :
2505 0 : static inline void skb_set_inner_mac_header(struct sk_buff *skb,
2506 : const int offset)
2507 : {
2508 0 : skb_reset_inner_mac_header(skb);
2509 0 : skb->inner_mac_header += offset;
2510 0 : }
2511 458 : static inline bool skb_transport_header_was_set(const struct sk_buff *skb)
2512 : {
2513 458 : return skb->transport_header != (typeof(skb->transport_header))~0U;
2514 : }
2515 :
2516 2562 : static inline unsigned char *skb_transport_header(const struct sk_buff *skb)
2517 : {
2518 1727 : return skb->head + skb->transport_header;
2519 : }
2520 :
2521 2048 : static inline void skb_reset_transport_header(struct sk_buff *skb)
2522 : {
2523 1341 : skb->transport_header = skb->data - skb->head;
2524 16 : }
2525 :
2526 1139 : static inline void skb_set_transport_header(struct sk_buff *skb,
2527 : const int offset)
2528 : {
2529 1139 : skb_reset_transport_header(skb);
2530 1137 : skb->transport_header += offset;
2531 432 : }
2532 :
2533 8358 : static inline unsigned char *skb_network_header(const struct sk_buff *skb)
2534 : {
2535 7156 : return skb->head + skb->network_header;
2536 : }
2537 :
2538 2333 : static inline void skb_reset_network_header(struct sk_buff *skb)
2539 : {
2540 892 : skb->network_header = skb->data - skb->head;
2541 0 : }
2542 :
2543 1441 : static inline void skb_set_network_header(struct sk_buff *skb, const int offset)
2544 : {
2545 1441 : skb_reset_network_header(skb);
2546 1441 : skb->network_header += offset;
2547 0 : }
2548 :
2549 1181 : static inline unsigned char *skb_mac_header(const struct sk_buff *skb)
2550 : {
2551 1181 : return skb->head + skb->mac_header;
2552 : }
2553 :
2554 0 : static inline int skb_mac_offset(const struct sk_buff *skb)
2555 : {
2556 0 : return skb_mac_header(skb) - skb->data;
2557 : }
2558 :
2559 0 : static inline u32 skb_mac_header_len(const struct sk_buff *skb)
2560 : {
2561 0 : return skb->network_header - skb->mac_header;
2562 : }
2563 :
2564 374 : static inline int skb_mac_header_was_set(const struct sk_buff *skb)
2565 : {
2566 374 : return skb->mac_header != (typeof(skb->mac_header))~0U;
2567 : }
2568 :
2569 0 : static inline void skb_unset_mac_header(struct sk_buff *skb)
2570 : {
2571 0 : skb->mac_header = (typeof(skb->mac_header))~0U;
2572 : }
2573 :
2574 1619 : static inline void skb_reset_mac_header(struct sk_buff *skb)
2575 : {
2576 1619 : skb->mac_header = skb->data - skb->head;
2577 0 : }
2578 :
2579 : static inline void skb_set_mac_header(struct sk_buff *skb, const int offset)
2580 : {
2581 : skb_reset_mac_header(skb);
2582 : skb->mac_header += offset;
2583 : }
2584 :
2585 0 : static inline void skb_pop_mac_header(struct sk_buff *skb)
2586 : {
2587 0 : skb->mac_header = skb->network_header;
2588 : }
2589 :
2590 2 : static inline void skb_probe_transport_header(struct sk_buff *skb)
2591 : {
2592 2 : struct flow_keys_basic keys;
2593 :
2594 2 : if (skb_transport_header_was_set(skb))
2595 0 : return;
2596 :
2597 2 : if (skb_flow_dissect_flow_keys_basic(NULL, skb, &keys,
2598 : NULL, 0, 0, 0, 0))
2599 2 : skb_set_transport_header(skb, keys.control.thoff);
2600 : }
2601 :
2602 : static inline void skb_mac_header_rebuild(struct sk_buff *skb)
2603 : {
2604 : if (skb_mac_header_was_set(skb)) {
2605 : const unsigned char *old_mac = skb_mac_header(skb);
2606 :
2607 : skb_set_mac_header(skb, -skb->mac_len);
2608 : memmove(skb_mac_header(skb), old_mac, skb->mac_len);
2609 : }
2610 : }
2611 :
2612 875 : static inline int skb_checksum_start_offset(const struct sk_buff *skb)
2613 : {
2614 875 : return skb->csum_start - skb_headroom(skb);
2615 : }
2616 :
2617 0 : static inline unsigned char *skb_checksum_start(const struct sk_buff *skb)
2618 : {
2619 0 : return skb->head + skb->csum_start;
2620 : }
2621 :
2622 405 : static inline int skb_transport_offset(const struct sk_buff *skb)
2623 : {
2624 405 : return skb_transport_header(skb) - skb->data;
2625 : }
2626 :
2627 454 : static inline u32 skb_network_header_len(const struct sk_buff *skb)
2628 : {
2629 454 : return skb->transport_header - skb->network_header;
2630 : }
2631 :
2632 : static inline u32 skb_inner_network_header_len(const struct sk_buff *skb)
2633 : {
2634 : return skb->inner_transport_header - skb->inner_network_header;
2635 : }
2636 :
2637 717 : static inline int skb_network_offset(const struct sk_buff *skb)
2638 : {
2639 715 : return skb_network_header(skb) - skb->data;
2640 : }
2641 :
2642 0 : static inline int skb_inner_network_offset(const struct sk_buff *skb)
2643 : {
2644 0 : return skb_inner_network_header(skb) - skb->data;
2645 : }
2646 :
2647 0 : static inline int pskb_network_may_pull(struct sk_buff *skb, unsigned int len)
2648 : {
2649 0 : return pskb_may_pull(skb, skb_network_offset(skb) + len);
2650 : }
2651 :
2652 : /*
2653 : * CPUs often take a performance hit when accessing unaligned memory
2654 : * locations. The actual performance hit varies, it can be small if the
2655 : * hardware handles it or large if we have to take an exception and fix it
2656 : * in software.
2657 : *
2658 : * Since an ethernet header is 14 bytes network drivers often end up with
2659 : * the IP header at an unaligned offset. The IP header can be aligned by
2660 : * shifting the start of the packet by 2 bytes. Drivers should do this
2661 : * with:
2662 : *
2663 : * skb_reserve(skb, NET_IP_ALIGN);
2664 : *
2665 : * The downside to this alignment of the IP header is that the DMA is now
2666 : * unaligned. On some architectures the cost of an unaligned DMA is high
2667 : * and this cost outweighs the gains made by aligning the IP header.
2668 : *
2669 : * Since this trade off varies between architectures, we allow NET_IP_ALIGN
2670 : * to be overridden.
2671 : */
2672 : #ifndef NET_IP_ALIGN
2673 : #define NET_IP_ALIGN 2
2674 : #endif
2675 :
2676 : /*
2677 : * The networking layer reserves some headroom in skb data (via
2678 : * dev_alloc_skb). This is used to avoid having to reallocate skb data when
2679 : * the header has to grow. In the default case, if the header has to grow
2680 : * 32 bytes or less we avoid the reallocation.
2681 : *
2682 : * Unfortunately this headroom changes the DMA alignment of the resulting
2683 : * network packet. As for NET_IP_ALIGN, this unaligned DMA is expensive
2684 : * on some architectures. An architecture can override this value,
2685 : * perhaps setting it to a cacheline in size (since that will maintain
2686 : * cacheline alignment of the DMA). It must be a power of 2.
2687 : *
2688 : * Various parts of the networking layer expect at least 32 bytes of
2689 : * headroom, you should not reduce this.
2690 : *
2691 : * Using max(32, L1_CACHE_BYTES) makes sense (especially with RPS)
2692 : * to reduce average number of cache lines per packet.
2693 : * get_rps_cpu() for example only access one 64 bytes aligned block :
2694 : * NET_IP_ALIGN(2) + ethernet_header(14) + IP_header(20/40) + ports(8)
2695 : */
2696 : #ifndef NET_SKB_PAD
2697 : #define NET_SKB_PAD max(32, L1_CACHE_BYTES)
2698 : #endif
2699 :
2700 : int ___pskb_trim(struct sk_buff *skb, unsigned int len);
2701 :
2702 16 : static inline void __skb_set_length(struct sk_buff *skb, unsigned int len)
2703 : {
2704 16 : if (WARN_ON(skb_is_nonlinear(skb)))
2705 : return;
2706 16 : skb->len = len;
2707 16 : skb_set_tail_pointer(skb, len);
2708 : }
2709 :
2710 16 : static inline void __skb_trim(struct sk_buff *skb, unsigned int len)
2711 : {
2712 16 : __skb_set_length(skb, len);
2713 16 : }
2714 :
2715 : void skb_trim(struct sk_buff *skb, unsigned int len);
2716 :
2717 0 : static inline int __pskb_trim(struct sk_buff *skb, unsigned int len)
2718 : {
2719 0 : if (skb->data_len)
2720 0 : return ___pskb_trim(skb, len);
2721 0 : __skb_trim(skb, len);
2722 0 : return 0;
2723 : }
2724 :
2725 17 : static inline int pskb_trim(struct sk_buff *skb, unsigned int len)
2726 : {
2727 17 : return (len < skb->len) ? __pskb_trim(skb, len) : 0;
2728 : }
2729 :
2730 : /**
2731 : * pskb_trim_unique - remove end from a paged unique (not cloned) buffer
2732 : * @skb: buffer to alter
2733 : * @len: new length
2734 : *
2735 : * This is identical to pskb_trim except that the caller knows that
2736 : * the skb is not cloned so we should never get an error due to out-
2737 : * of-memory.
2738 : */
2739 0 : static inline void pskb_trim_unique(struct sk_buff *skb, unsigned int len)
2740 : {
2741 0 : int err = pskb_trim(skb, len);
2742 0 : BUG_ON(err);
2743 0 : }
2744 :
2745 0 : static inline int __skb_grow(struct sk_buff *skb, unsigned int len)
2746 : {
2747 0 : unsigned int diff = len - skb->len;
2748 :
2749 0 : if (skb_tailroom(skb) < diff) {
2750 0 : int ret = pskb_expand_head(skb, 0, diff - skb_tailroom(skb),
2751 : GFP_ATOMIC);
2752 0 : if (ret)
2753 : return ret;
2754 : }
2755 0 : __skb_set_length(skb, len);
2756 0 : return 0;
2757 : }
2758 :
2759 : /**
2760 : * skb_orphan - orphan a buffer
2761 : * @skb: buffer to orphan
2762 : *
2763 : * If a buffer currently has an owner then we call the owner's
2764 : * destructor function and make the @skb unowned. The buffer continues
2765 : * to exist but is no longer charged to its former owner.
2766 : */
2767 3962 : static inline void skb_orphan(struct sk_buff *skb)
2768 : {
2769 3962 : if (skb->destructor) {
2770 0 : skb->destructor(skb);
2771 0 : skb->destructor = NULL;
2772 0 : skb->sk = NULL;
2773 : } else {
2774 3962 : BUG_ON(skb->sk);
2775 : }
2776 3962 : }
2777 :
2778 : /**
2779 : * skb_orphan_frags - orphan the frags contained in a buffer
2780 : * @skb: buffer to orphan frags from
2781 : * @gfp_mask: allocation mask for replacement pages
2782 : *
2783 : * For each frag in the SKB which needs a destructor (i.e. has an
2784 : * owner) create a copy of that frag and release the original
2785 : * page by calling the destructor.
2786 : */
2787 1545 : static inline int skb_orphan_frags(struct sk_buff *skb, gfp_t gfp_mask)
2788 : {
2789 1545 : if (likely(!skb_zcopy(skb)))
2790 : return 0;
2791 0 : if (!skb_zcopy_is_nouarg(skb) &&
2792 0 : skb_uarg(skb)->callback == msg_zerocopy_callback)
2793 : return 0;
2794 0 : return skb_copy_ubufs(skb, gfp_mask);
2795 : }
2796 :
2797 : /* Frags must be orphaned, even if refcounted, if skb might loop to rx path */
2798 1358 : static inline int skb_orphan_frags_rx(struct sk_buff *skb, gfp_t gfp_mask)
2799 : {
2800 1358 : if (likely(!skb_zcopy(skb)))
2801 : return 0;
2802 0 : return skb_copy_ubufs(skb, gfp_mask);
2803 : }
2804 :
2805 : /**
2806 : * __skb_queue_purge - empty a list
2807 : * @list: list to empty
2808 : *
2809 : * Delete all buffers on an &sk_buff list. Each buffer is removed from
2810 : * the list and one reference dropped. This function does not take the
2811 : * list lock and the caller must hold the relevant locks to use it.
2812 : */
2813 150 : static inline void __skb_queue_purge(struct sk_buff_head *list)
2814 : {
2815 150 : struct sk_buff *skb;
2816 150 : while ((skb = __skb_dequeue(list)) != NULL)
2817 0 : kfree_skb(skb);
2818 150 : }
2819 : void skb_queue_purge(struct sk_buff_head *list);
2820 :
2821 : unsigned int skb_rbtree_purge(struct rb_root *root);
2822 :
2823 : void *__netdev_alloc_frag_align(unsigned int fragsz, unsigned int align_mask);
2824 :
2825 : /**
2826 : * netdev_alloc_frag - allocate a page fragment
2827 : * @fragsz: fragment size
2828 : *
2829 : * Allocates a frag from a page for receive buffer.
2830 : * Uses GFP_ATOMIC allocations.
2831 : */
2832 : static inline void *netdev_alloc_frag(unsigned int fragsz)
2833 : {
2834 : return __netdev_alloc_frag_align(fragsz, ~0u);
2835 : }
2836 :
2837 : static inline void *netdev_alloc_frag_align(unsigned int fragsz,
2838 : unsigned int align)
2839 : {
2840 : WARN_ON_ONCE(!is_power_of_2(align));
2841 : return __netdev_alloc_frag_align(fragsz, -align);
2842 : }
2843 :
2844 : struct sk_buff *__netdev_alloc_skb(struct net_device *dev, unsigned int length,
2845 : gfp_t gfp_mask);
2846 :
2847 : /**
2848 : * netdev_alloc_skb - allocate an skbuff for rx on a specific device
2849 : * @dev: network device to receive on
2850 : * @length: length to allocate
2851 : *
2852 : * Allocate a new &sk_buff and assign it a usage count of one. The
2853 : * buffer has unspecified headroom built in. Users should allocate
2854 : * the headroom they think they need without accounting for the
2855 : * built in space. The built in space is used for optimisations.
2856 : *
2857 : * %NULL is returned if there is no free memory. Although this function
2858 : * allocates memory it can be called from an interrupt.
2859 : */
2860 : static inline struct sk_buff *netdev_alloc_skb(struct net_device *dev,
2861 : unsigned int length)
2862 : {
2863 : return __netdev_alloc_skb(dev, length, GFP_ATOMIC);
2864 : }
2865 :
2866 : /* legacy helper around __netdev_alloc_skb() */
2867 : static inline struct sk_buff *__dev_alloc_skb(unsigned int length,
2868 : gfp_t gfp_mask)
2869 : {
2870 : return __netdev_alloc_skb(NULL, length, gfp_mask);
2871 : }
2872 :
2873 : /* legacy helper around netdev_alloc_skb() */
2874 : static inline struct sk_buff *dev_alloc_skb(unsigned int length)
2875 : {
2876 : return netdev_alloc_skb(NULL, length);
2877 : }
2878 :
2879 :
2880 : static inline struct sk_buff *__netdev_alloc_skb_ip_align(struct net_device *dev,
2881 : unsigned int length, gfp_t gfp)
2882 : {
2883 : struct sk_buff *skb = __netdev_alloc_skb(dev, length + NET_IP_ALIGN, gfp);
2884 :
2885 : if (NET_IP_ALIGN && skb)
2886 : skb_reserve(skb, NET_IP_ALIGN);
2887 : return skb;
2888 : }
2889 :
2890 : static inline struct sk_buff *netdev_alloc_skb_ip_align(struct net_device *dev,
2891 : unsigned int length)
2892 : {
2893 : return __netdev_alloc_skb_ip_align(dev, length, GFP_ATOMIC);
2894 : }
2895 :
2896 0 : static inline void skb_free_frag(void *addr)
2897 : {
2898 0 : page_frag_free(addr);
2899 0 : }
2900 :
2901 : void *__napi_alloc_frag_align(unsigned int fragsz, unsigned int align_mask);
2902 :
2903 : static inline void *napi_alloc_frag(unsigned int fragsz)
2904 : {
2905 : return __napi_alloc_frag_align(fragsz, ~0u);
2906 : }
2907 :
2908 : static inline void *napi_alloc_frag_align(unsigned int fragsz,
2909 : unsigned int align)
2910 : {
2911 : WARN_ON_ONCE(!is_power_of_2(align));
2912 : return __napi_alloc_frag_align(fragsz, -align);
2913 : }
2914 :
2915 : struct sk_buff *__napi_alloc_skb(struct napi_struct *napi,
2916 : unsigned int length, gfp_t gfp_mask);
2917 723 : static inline struct sk_buff *napi_alloc_skb(struct napi_struct *napi,
2918 : unsigned int length)
2919 : {
2920 723 : return __napi_alloc_skb(napi, length, GFP_ATOMIC);
2921 : }
2922 : void napi_consume_skb(struct sk_buff *skb, int budget);
2923 :
2924 : void napi_skb_free_stolen_head(struct sk_buff *skb);
2925 : void __kfree_skb_defer(struct sk_buff *skb);
2926 :
2927 : /**
2928 : * __dev_alloc_pages - allocate page for network Rx
2929 : * @gfp_mask: allocation priority. Set __GFP_NOMEMALLOC if not for network Rx
2930 : * @order: size of the allocation
2931 : *
2932 : * Allocate a new page.
2933 : *
2934 : * %NULL is returned if there is no free memory.
2935 : */
2936 0 : static inline struct page *__dev_alloc_pages(gfp_t gfp_mask,
2937 : unsigned int order)
2938 : {
2939 : /* This piece of code contains several assumptions.
2940 : * 1. This is for device Rx, therefor a cold page is preferred.
2941 : * 2. The expectation is the user wants a compound page.
2942 : * 3. If requesting a order 0 page it will not be compound
2943 : * due to the check to see if order has a value in prep_new_page
2944 : * 4. __GFP_MEMALLOC is ignored if __GFP_NOMEMALLOC is set due to
2945 : * code in gfp_to_alloc_flags that should be enforcing this.
2946 : */
2947 0 : gfp_mask |= __GFP_COMP | __GFP_MEMALLOC;
2948 :
2949 0 : return alloc_pages_node(NUMA_NO_NODE, gfp_mask, order);
2950 : }
2951 :
2952 0 : static inline struct page *dev_alloc_pages(unsigned int order)
2953 : {
2954 0 : return __dev_alloc_pages(GFP_ATOMIC | __GFP_NOWARN, order);
2955 : }
2956 :
2957 : /**
2958 : * __dev_alloc_page - allocate a page for network Rx
2959 : * @gfp_mask: allocation priority. Set __GFP_NOMEMALLOC if not for network Rx
2960 : *
2961 : * Allocate a new page.
2962 : *
2963 : * %NULL is returned if there is no free memory.
2964 : */
2965 : static inline struct page *__dev_alloc_page(gfp_t gfp_mask)
2966 : {
2967 : return __dev_alloc_pages(gfp_mask, 0);
2968 : }
2969 :
2970 0 : static inline struct page *dev_alloc_page(void)
2971 : {
2972 0 : return dev_alloc_pages(0);
2973 : }
2974 :
2975 : /**
2976 : * dev_page_is_reusable - check whether a page can be reused for network Rx
2977 : * @page: the page to test
2978 : *
2979 : * A page shouldn't be considered for reusing/recycling if it was allocated
2980 : * under memory pressure or at a distant memory node.
2981 : *
2982 : * Returns false if this page should be returned to page allocator, true
2983 : * otherwise.
2984 : */
2985 : static inline bool dev_page_is_reusable(const struct page *page)
2986 : {
2987 : return likely(page_to_nid(page) == numa_mem_id() &&
2988 : !page_is_pfmemalloc(page));
2989 : }
2990 :
2991 : /**
2992 : * skb_propagate_pfmemalloc - Propagate pfmemalloc if skb is allocated after RX page
2993 : * @page: The page that was allocated from skb_alloc_page
2994 : * @skb: The skb that may need pfmemalloc set
2995 : */
2996 0 : static inline void skb_propagate_pfmemalloc(const struct page *page,
2997 : struct sk_buff *skb)
2998 : {
2999 0 : if (page_is_pfmemalloc(page))
3000 0 : skb->pfmemalloc = true;
3001 : }
3002 :
3003 : /**
3004 : * skb_frag_off() - Returns the offset of a skb fragment
3005 : * @frag: the paged fragment
3006 : */
3007 1097 : static inline unsigned int skb_frag_off(const skb_frag_t *frag)
3008 : {
3009 362 : return frag->bv_offset;
3010 : }
3011 :
3012 : /**
3013 : * skb_frag_off_add() - Increments the offset of a skb fragment by @delta
3014 : * @frag: skb fragment
3015 : * @delta: value to add
3016 : */
3017 0 : static inline void skb_frag_off_add(skb_frag_t *frag, int delta)
3018 : {
3019 0 : frag->bv_offset += delta;
3020 : }
3021 :
3022 : /**
3023 : * skb_frag_off_set() - Sets the offset of a skb fragment
3024 : * @frag: skb fragment
3025 : * @offset: offset of fragment
3026 : */
3027 0 : static inline void skb_frag_off_set(skb_frag_t *frag, unsigned int offset)
3028 : {
3029 0 : frag->bv_offset = offset;
3030 : }
3031 :
3032 : /**
3033 : * skb_frag_off_copy() - Sets the offset of a skb fragment from another fragment
3034 : * @fragto: skb fragment where offset is set
3035 : * @fragfrom: skb fragment offset is copied from
3036 : */
3037 0 : static inline void skb_frag_off_copy(skb_frag_t *fragto,
3038 : const skb_frag_t *fragfrom)
3039 : {
3040 0 : fragto->bv_offset = fragfrom->bv_offset;
3041 : }
3042 :
3043 : /**
3044 : * skb_frag_page - retrieve the page referred to by a paged fragment
3045 : * @frag: the paged fragment
3046 : *
3047 : * Returns the &struct page associated with @frag.
3048 : */
3049 2510 : static inline struct page *skb_frag_page(const skb_frag_t *frag)
3050 : {
3051 1047 : return frag->bv_page;
3052 : }
3053 :
3054 : /**
3055 : * __skb_frag_ref - take an addition reference on a paged fragment.
3056 : * @frag: the paged fragment
3057 : *
3058 : * Takes an additional reference on the paged fragment @frag.
3059 : */
3060 361 : static inline void __skb_frag_ref(skb_frag_t *frag)
3061 : {
3062 0 : get_page(skb_frag_page(frag));
3063 : }
3064 :
3065 : /**
3066 : * skb_frag_ref - take an addition reference on a paged fragment of an skb.
3067 : * @skb: the buffer
3068 : * @f: the fragment offset.
3069 : *
3070 : * Takes an additional reference on the @f'th paged fragment of @skb.
3071 : */
3072 361 : static inline void skb_frag_ref(struct sk_buff *skb, int f)
3073 : {
3074 361 : __skb_frag_ref(&skb_shinfo(skb)->frags[f]);
3075 : }
3076 :
3077 : /**
3078 : * __skb_frag_unref - release a reference on a paged fragment.
3079 : * @frag: the paged fragment
3080 : *
3081 : * Releases a reference on the paged fragment @frag.
3082 : */
3083 1052 : static inline void __skb_frag_unref(skb_frag_t *frag)
3084 : {
3085 691 : put_page(skb_frag_page(frag));
3086 0 : }
3087 :
3088 : /**
3089 : * skb_frag_unref - release a reference on a paged fragment of an skb.
3090 : * @skb: the buffer
3091 : * @f: the fragment offset
3092 : *
3093 : * Releases a reference on the @f'th paged fragment of @skb.
3094 : */
3095 361 : static inline void skb_frag_unref(struct sk_buff *skb, int f)
3096 : {
3097 361 : __skb_frag_unref(&skb_shinfo(skb)->frags[f]);
3098 : }
3099 :
3100 : /**
3101 : * skb_frag_address - gets the address of the data contained in a paged fragment
3102 : * @frag: the paged fragment buffer
3103 : *
3104 : * Returns the address of the data within @frag. The page must already
3105 : * be mapped.
3106 : */
3107 0 : static inline void *skb_frag_address(const skb_frag_t *frag)
3108 : {
3109 0 : return page_address(skb_frag_page(frag)) + skb_frag_off(frag);
3110 : }
3111 :
3112 : /**
3113 : * skb_frag_address_safe - gets the address of the data contained in a paged fragment
3114 : * @frag: the paged fragment buffer
3115 : *
3116 : * Returns the address of the data within @frag. Checks that the page
3117 : * is mapped and returns %NULL otherwise.
3118 : */
3119 : static inline void *skb_frag_address_safe(const skb_frag_t *frag)
3120 : {
3121 : void *ptr = page_address(skb_frag_page(frag));
3122 : if (unlikely(!ptr))
3123 : return NULL;
3124 :
3125 : return ptr + skb_frag_off(frag);
3126 : }
3127 :
3128 : /**
3129 : * skb_frag_page_copy() - sets the page in a fragment from another fragment
3130 : * @fragto: skb fragment where page is set
3131 : * @fragfrom: skb fragment page is copied from
3132 : */
3133 0 : static inline void skb_frag_page_copy(skb_frag_t *fragto,
3134 : const skb_frag_t *fragfrom)
3135 : {
3136 0 : fragto->bv_page = fragfrom->bv_page;
3137 : }
3138 :
3139 : /**
3140 : * __skb_frag_set_page - sets the page contained in a paged fragment
3141 : * @frag: the paged fragment
3142 : * @page: the page to set
3143 : *
3144 : * Sets the fragment @frag to contain @page.
3145 : */
3146 0 : static inline void __skb_frag_set_page(skb_frag_t *frag, struct page *page)
3147 : {
3148 0 : frag->bv_page = page;
3149 : }
3150 :
3151 : /**
3152 : * skb_frag_set_page - sets the page contained in a paged fragment of an skb
3153 : * @skb: the buffer
3154 : * @f: the fragment offset
3155 : * @page: the page to set
3156 : *
3157 : * Sets the @f'th fragment of @skb to contain @page.
3158 : */
3159 : static inline void skb_frag_set_page(struct sk_buff *skb, int f,
3160 : struct page *page)
3161 : {
3162 : __skb_frag_set_page(&skb_shinfo(skb)->frags[f], page);
3163 : }
3164 :
3165 : bool skb_page_frag_refill(unsigned int sz, struct page_frag *pfrag, gfp_t prio);
3166 :
3167 : /**
3168 : * skb_frag_dma_map - maps a paged fragment via the DMA API
3169 : * @dev: the device to map the fragment to
3170 : * @frag: the paged fragment to map
3171 : * @offset: the offset within the fragment (starting at the
3172 : * fragment's own offset)
3173 : * @size: the number of bytes to map
3174 : * @dir: the direction of the mapping (``PCI_DMA_*``)
3175 : *
3176 : * Maps the page associated with @frag to @device.
3177 : */
3178 : static inline dma_addr_t skb_frag_dma_map(struct device *dev,
3179 : const skb_frag_t *frag,
3180 : size_t offset, size_t size,
3181 : enum dma_data_direction dir)
3182 : {
3183 : return dma_map_page(dev, skb_frag_page(frag),
3184 : skb_frag_off(frag) + offset, size, dir);
3185 : }
3186 :
3187 0 : static inline struct sk_buff *pskb_copy(struct sk_buff *skb,
3188 : gfp_t gfp_mask)
3189 : {
3190 0 : return __pskb_copy(skb, skb_headroom(skb), gfp_mask);
3191 : }
3192 :
3193 :
3194 : static inline struct sk_buff *pskb_copy_for_clone(struct sk_buff *skb,
3195 : gfp_t gfp_mask)
3196 : {
3197 : return __pskb_copy_fclone(skb, skb_headroom(skb), gfp_mask, true);
3198 : }
3199 :
3200 :
3201 : /**
3202 : * skb_clone_writable - is the header of a clone writable
3203 : * @skb: buffer to check
3204 : * @len: length up to which to write
3205 : *
3206 : * Returns true if modifying the header part of the cloned buffer
3207 : * does not requires the data to be copied.
3208 : */
3209 3 : static inline int skb_clone_writable(const struct sk_buff *skb, unsigned int len)
3210 : {
3211 3 : return !skb_header_cloned(skb) &&
3212 3 : skb_headroom(skb) + len <= skb->hdr_len;
3213 : }
3214 :
3215 : static inline int skb_try_make_writable(struct sk_buff *skb,
3216 : unsigned int write_len)
3217 : {
3218 : return skb_cloned(skb) && !skb_clone_writable(skb, write_len) &&
3219 : pskb_expand_head(skb, 0, 0, GFP_ATOMIC);
3220 : }
3221 :
3222 0 : static inline int __skb_cow(struct sk_buff *skb, unsigned int headroom,
3223 : int cloned)
3224 : {
3225 0 : int delta = 0;
3226 :
3227 0 : if (headroom > skb_headroom(skb))
3228 0 : delta = headroom - skb_headroom(skb);
3229 :
3230 0 : if (delta || cloned)
3231 0 : return pskb_expand_head(skb, ALIGN(delta, NET_SKB_PAD), 0,
3232 : GFP_ATOMIC);
3233 : return 0;
3234 : }
3235 :
3236 : /**
3237 : * skb_cow - copy header of skb when it is required
3238 : * @skb: buffer to cow
3239 : * @headroom: needed headroom
3240 : *
3241 : * If the skb passed lacks sufficient headroom or its data part
3242 : * is shared, data is reallocated. If reallocation fails, an error
3243 : * is returned and original skb is not changed.
3244 : *
3245 : * The result is skb with writable area skb->head...skb->tail
3246 : * and at least @headroom of space at head.
3247 : */
3248 0 : static inline int skb_cow(struct sk_buff *skb, unsigned int headroom)
3249 : {
3250 0 : return __skb_cow(skb, headroom, skb_cloned(skb));
3251 : }
3252 :
3253 : /**
3254 : * skb_cow_head - skb_cow but only making the head writable
3255 : * @skb: buffer to cow
3256 : * @headroom: needed headroom
3257 : *
3258 : * This function is identical to skb_cow except that we replace the
3259 : * skb_cloned check by skb_header_cloned. It should be used when
3260 : * you only need to push on some header and do not need to modify
3261 : * the data.
3262 : */
3263 0 : static inline int skb_cow_head(struct sk_buff *skb, unsigned int headroom)
3264 : {
3265 0 : return __skb_cow(skb, headroom, skb_header_cloned(skb));
3266 : }
3267 :
3268 : /**
3269 : * skb_padto - pad an skbuff up to a minimal size
3270 : * @skb: buffer to pad
3271 : * @len: minimal length
3272 : *
3273 : * Pads up a buffer to ensure the trailing bytes exist and are
3274 : * blanked. If the buffer already contains sufficient data it
3275 : * is untouched. Otherwise it is extended. Returns zero on
3276 : * success. The skb is freed on error.
3277 : */
3278 : static inline int skb_padto(struct sk_buff *skb, unsigned int len)
3279 : {
3280 : unsigned int size = skb->len;
3281 : if (likely(size >= len))
3282 : return 0;
3283 : return skb_pad(skb, len - size);
3284 : }
3285 :
3286 : /**
3287 : * __skb_put_padto - increase size and pad an skbuff up to a minimal size
3288 : * @skb: buffer to pad
3289 : * @len: minimal length
3290 : * @free_on_error: free buffer on error
3291 : *
3292 : * Pads up a buffer to ensure the trailing bytes exist and are
3293 : * blanked. If the buffer already contains sufficient data it
3294 : * is untouched. Otherwise it is extended. Returns zero on
3295 : * success. The skb is freed on error if @free_on_error is true.
3296 : */
3297 : static inline int __must_check __skb_put_padto(struct sk_buff *skb,
3298 : unsigned int len,
3299 : bool free_on_error)
3300 : {
3301 : unsigned int size = skb->len;
3302 :
3303 : if (unlikely(size < len)) {
3304 : len -= size;
3305 : if (__skb_pad(skb, len, free_on_error))
3306 : return -ENOMEM;
3307 : __skb_put(skb, len);
3308 : }
3309 : return 0;
3310 : }
3311 :
3312 : /**
3313 : * skb_put_padto - increase size and pad an skbuff up to a minimal size
3314 : * @skb: buffer to pad
3315 : * @len: minimal length
3316 : *
3317 : * Pads up a buffer to ensure the trailing bytes exist and are
3318 : * blanked. If the buffer already contains sufficient data it
3319 : * is untouched. Otherwise it is extended. Returns zero on
3320 : * success. The skb is freed on error.
3321 : */
3322 : static inline int __must_check skb_put_padto(struct sk_buff *skb, unsigned int len)
3323 : {
3324 : return __skb_put_padto(skb, len, true);
3325 : }
3326 :
3327 : static inline int skb_add_data(struct sk_buff *skb,
3328 : struct iov_iter *from, int copy)
3329 : {
3330 : const int off = skb->len;
3331 :
3332 : if (skb->ip_summed == CHECKSUM_NONE) {
3333 : __wsum csum = 0;
3334 : if (csum_and_copy_from_iter_full(skb_put(skb, copy), copy,
3335 : &csum, from)) {
3336 : skb->csum = csum_block_add(skb->csum, csum, off);
3337 : return 0;
3338 : }
3339 : } else if (copy_from_iter_full(skb_put(skb, copy), copy, from))
3340 : return 0;
3341 :
3342 : __skb_trim(skb, off);
3343 : return -EFAULT;
3344 : }
3345 :
3346 411 : static inline bool skb_can_coalesce(struct sk_buff *skb, int i,
3347 : const struct page *page, int off)
3348 : {
3349 411 : if (skb_zcopy(skb))
3350 : return false;
3351 411 : if (i) {
3352 50 : const skb_frag_t *frag = &skb_shinfo(skb)->frags[i - 1];
3353 :
3354 100 : return page == skb_frag_page(frag) &&
3355 50 : off == skb_frag_off(frag) + skb_frag_size(frag);
3356 : }
3357 : return false;
3358 : }
3359 :
3360 361 : static inline int __skb_linearize(struct sk_buff *skb)
3361 : {
3362 361 : return __pskb_pull_tail(skb, skb->data_len) ? 0 : -ENOMEM;
3363 : }
3364 :
3365 : /**
3366 : * skb_linearize - convert paged skb to linear one
3367 : * @skb: buffer to linarize
3368 : *
3369 : * If there is no free memory -ENOMEM is returned, otherwise zero
3370 : * is returned and the old skb data released.
3371 : */
3372 0 : static inline int skb_linearize(struct sk_buff *skb)
3373 : {
3374 0 : return skb_is_nonlinear(skb) ? __skb_linearize(skb) : 0;
3375 : }
3376 :
3377 : /**
3378 : * skb_has_shared_frag - can any frag be overwritten
3379 : * @skb: buffer to test
3380 : *
3381 : * Return true if the skb has at least one frag that might be modified
3382 : * by an external entity (as in vmsplice()/sendfile())
3383 : */
3384 430 : static inline bool skb_has_shared_frag(const struct sk_buff *skb)
3385 : {
3386 430 : return skb_is_nonlinear(skb) &&
3387 0 : skb_shinfo(skb)->flags & SKBFL_SHARED_FRAG;
3388 : }
3389 :
3390 : /**
3391 : * skb_linearize_cow - make sure skb is linear and writable
3392 : * @skb: buffer to process
3393 : *
3394 : * If there is no free memory -ENOMEM is returned, otherwise zero
3395 : * is returned and the old skb data released.
3396 : */
3397 : static inline int skb_linearize_cow(struct sk_buff *skb)
3398 : {
3399 : return skb_is_nonlinear(skb) || skb_cloned(skb) ?
3400 : __skb_linearize(skb) : 0;
3401 : }
3402 :
3403 : static __always_inline void
3404 2 : __skb_postpull_rcsum(struct sk_buff *skb, const void *start, unsigned int len,
3405 : unsigned int off)
3406 : {
3407 2 : if (skb->ip_summed == CHECKSUM_COMPLETE)
3408 0 : skb->csum = csum_block_sub(skb->csum,
3409 : csum_partial(start, len, 0), off);
3410 2 : else if (skb->ip_summed == CHECKSUM_PARTIAL &&
3411 0 : skb_checksum_start_offset(skb) < 0)
3412 0 : skb->ip_summed = CHECKSUM_NONE;
3413 : }
3414 :
3415 : /**
3416 : * skb_postpull_rcsum - update checksum for received skb after pull
3417 : * @skb: buffer to update
3418 : * @start: start of data before pull
3419 : * @len: length of data pulled
3420 : *
3421 : * After doing a pull on a received packet, you need to call this to
3422 : * update the CHECKSUM_COMPLETE checksum, or set ip_summed to
3423 : * CHECKSUM_NONE so that it can be recomputed from scratch.
3424 : */
3425 2 : static inline void skb_postpull_rcsum(struct sk_buff *skb,
3426 : const void *start, unsigned int len)
3427 : {
3428 2 : __skb_postpull_rcsum(skb, start, len, 0);
3429 2 : }
3430 :
3431 : static __always_inline void
3432 0 : __skb_postpush_rcsum(struct sk_buff *skb, const void *start, unsigned int len,
3433 : unsigned int off)
3434 : {
3435 0 : if (skb->ip_summed == CHECKSUM_COMPLETE)
3436 0 : skb->csum = csum_block_add(skb->csum,
3437 : csum_partial(start, len, 0), off);
3438 : }
3439 :
3440 : /**
3441 : * skb_postpush_rcsum - update checksum for received skb after push
3442 : * @skb: buffer to update
3443 : * @start: start of data after push
3444 : * @len: length of data pushed
3445 : *
3446 : * After doing a push on a received packet, you need to call this to
3447 : * update the CHECKSUM_COMPLETE checksum.
3448 : */
3449 0 : static inline void skb_postpush_rcsum(struct sk_buff *skb,
3450 : const void *start, unsigned int len)
3451 : {
3452 0 : __skb_postpush_rcsum(skb, start, len, 0);
3453 0 : }
3454 :
3455 : void *skb_pull_rcsum(struct sk_buff *skb, unsigned int len);
3456 :
3457 : /**
3458 : * skb_push_rcsum - push skb and update receive checksum
3459 : * @skb: buffer to update
3460 : * @len: length of data pulled
3461 : *
3462 : * This function performs an skb_push on the packet and updates
3463 : * the CHECKSUM_COMPLETE checksum. It should be used on
3464 : * receive path processing instead of skb_push unless you know
3465 : * that the checksum difference is zero (e.g., a valid IP header)
3466 : * or you are setting ip_summed to CHECKSUM_NONE.
3467 : */
3468 0 : static inline void *skb_push_rcsum(struct sk_buff *skb, unsigned int len)
3469 : {
3470 0 : skb_push(skb, len);
3471 0 : skb_postpush_rcsum(skb, skb->data, len);
3472 0 : return skb->data;
3473 : }
3474 :
3475 : int pskb_trim_rcsum_slow(struct sk_buff *skb, unsigned int len);
3476 : /**
3477 : * pskb_trim_rcsum - trim received skb and update checksum
3478 : * @skb: buffer to trim
3479 : * @len: new length
3480 : *
3481 : * This is exactly the same as pskb_trim except that it ensures the
3482 : * checksum of received packets are still valid after the operation.
3483 : * It can change skb pointers.
3484 : */
3485 :
3486 456 : static inline int pskb_trim_rcsum(struct sk_buff *skb, unsigned int len)
3487 : {
3488 456 : if (likely(len >= skb->len))
3489 : return 0;
3490 0 : return pskb_trim_rcsum_slow(skb, len);
3491 : }
3492 :
3493 0 : static inline int __skb_trim_rcsum(struct sk_buff *skb, unsigned int len)
3494 : {
3495 0 : if (skb->ip_summed == CHECKSUM_COMPLETE)
3496 0 : skb->ip_summed = CHECKSUM_NONE;
3497 0 : __skb_trim(skb, len);
3498 0 : return 0;
3499 : }
3500 :
3501 0 : static inline int __skb_grow_rcsum(struct sk_buff *skb, unsigned int len)
3502 : {
3503 0 : if (skb->ip_summed == CHECKSUM_COMPLETE)
3504 0 : skb->ip_summed = CHECKSUM_NONE;
3505 0 : return __skb_grow(skb, len);
3506 : }
3507 :
3508 : #define rb_to_skb(rb) rb_entry_safe(rb, struct sk_buff, rbnode)
3509 : #define skb_rb_first(root) rb_to_skb(rb_first(root))
3510 : #define skb_rb_last(root) rb_to_skb(rb_last(root))
3511 : #define skb_rb_next(skb) rb_to_skb(rb_next(&(skb)->rbnode))
3512 : #define skb_rb_prev(skb) rb_to_skb(rb_prev(&(skb)->rbnode))
3513 :
3514 : #define skb_queue_walk(queue, skb) \
3515 : for (skb = (queue)->next; \
3516 : skb != (struct sk_buff *)(queue); \
3517 : skb = skb->next)
3518 :
3519 : #define skb_queue_walk_safe(queue, skb, tmp) \
3520 : for (skb = (queue)->next, tmp = skb->next; \
3521 : skb != (struct sk_buff *)(queue); \
3522 : skb = tmp, tmp = skb->next)
3523 :
3524 : #define skb_queue_walk_from(queue, skb) \
3525 : for (; skb != (struct sk_buff *)(queue); \
3526 : skb = skb->next)
3527 :
3528 : #define skb_rbtree_walk(skb, root) \
3529 : for (skb = skb_rb_first(root); skb != NULL; \
3530 : skb = skb_rb_next(skb))
3531 :
3532 : #define skb_rbtree_walk_from(skb) \
3533 : for (; skb != NULL; \
3534 : skb = skb_rb_next(skb))
3535 :
3536 : #define skb_rbtree_walk_from_safe(skb, tmp) \
3537 : for (; tmp = skb ? skb_rb_next(skb) : NULL, (skb != NULL); \
3538 : skb = tmp)
3539 :
3540 : #define skb_queue_walk_from_safe(queue, skb, tmp) \
3541 : for (tmp = skb->next; \
3542 : skb != (struct sk_buff *)(queue); \
3543 : skb = tmp, tmp = skb->next)
3544 :
3545 : #define skb_queue_reverse_walk(queue, skb) \
3546 : for (skb = (queue)->prev; \
3547 : skb != (struct sk_buff *)(queue); \
3548 : skb = skb->prev)
3549 :
3550 : #define skb_queue_reverse_walk_safe(queue, skb, tmp) \
3551 : for (skb = (queue)->prev, tmp = skb->prev; \
3552 : skb != (struct sk_buff *)(queue); \
3553 : skb = tmp, tmp = skb->prev)
3554 :
3555 : #define skb_queue_reverse_walk_from_safe(queue, skb, tmp) \
3556 : for (tmp = skb->prev; \
3557 : skb != (struct sk_buff *)(queue); \
3558 : skb = tmp, tmp = skb->prev)
3559 :
3560 1803 : static inline bool skb_has_frag_list(const struct sk_buff *skb)
3561 : {
3562 1442 : return skb_shinfo(skb)->frag_list != NULL;
3563 : }
3564 :
3565 0 : static inline void skb_frag_list_init(struct sk_buff *skb)
3566 : {
3567 0 : skb_shinfo(skb)->frag_list = NULL;
3568 : }
3569 :
3570 : #define skb_walk_frags(skb, iter) \
3571 : for (iter = skb_shinfo(skb)->frag_list; iter; iter = iter->next)
3572 :
3573 :
3574 : int __skb_wait_for_more_packets(struct sock *sk, struct sk_buff_head *queue,
3575 : int *err, long *timeo_p,
3576 : const struct sk_buff *skb);
3577 : struct sk_buff *__skb_try_recv_from_queue(struct sock *sk,
3578 : struct sk_buff_head *queue,
3579 : unsigned int flags,
3580 : int *off, int *err,
3581 : struct sk_buff **last);
3582 : struct sk_buff *__skb_try_recv_datagram(struct sock *sk,
3583 : struct sk_buff_head *queue,
3584 : unsigned int flags, int *off, int *err,
3585 : struct sk_buff **last);
3586 : struct sk_buff *__skb_recv_datagram(struct sock *sk,
3587 : struct sk_buff_head *sk_queue,
3588 : unsigned int flags, int *off, int *err);
3589 : struct sk_buff *skb_recv_datagram(struct sock *sk, unsigned flags, int noblock,
3590 : int *err);
3591 : __poll_t datagram_poll(struct file *file, struct socket *sock,
3592 : struct poll_table_struct *wait);
3593 : int skb_copy_datagram_iter(const struct sk_buff *from, int offset,
3594 : struct iov_iter *to, int size);
3595 4316 : static inline int skb_copy_datagram_msg(const struct sk_buff *from, int offset,
3596 : struct msghdr *msg, int size)
3597 : {
3598 4316 : return skb_copy_datagram_iter(from, offset, &msg->msg_iter, size);
3599 : }
3600 : int skb_copy_and_csum_datagram_msg(struct sk_buff *skb, int hlen,
3601 : struct msghdr *msg);
3602 : int skb_copy_and_hash_datagram_iter(const struct sk_buff *skb, int offset,
3603 : struct iov_iter *to, int len,
3604 : struct ahash_request *hash);
3605 : int skb_copy_datagram_from_iter(struct sk_buff *skb, int offset,
3606 : struct iov_iter *from, int len);
3607 : int zerocopy_sg_from_iter(struct sk_buff *skb, struct iov_iter *frm);
3608 : void skb_free_datagram(struct sock *sk, struct sk_buff *skb);
3609 : void __skb_free_datagram_locked(struct sock *sk, struct sk_buff *skb, int len);
3610 : static inline void skb_free_datagram_locked(struct sock *sk,
3611 : struct sk_buff *skb)
3612 : {
3613 : __skb_free_datagram_locked(sk, skb, 0);
3614 : }
3615 : int skb_kill_datagram(struct sock *sk, struct sk_buff *skb, unsigned int flags);
3616 : int skb_copy_bits(const struct sk_buff *skb, int offset, void *to, int len);
3617 : int skb_store_bits(struct sk_buff *skb, int offset, const void *from, int len);
3618 : __wsum skb_copy_and_csum_bits(const struct sk_buff *skb, int offset, u8 *to,
3619 : int len);
3620 : int skb_splice_bits(struct sk_buff *skb, struct sock *sk, unsigned int offset,
3621 : struct pipe_inode_info *pipe, unsigned int len,
3622 : unsigned int flags);
3623 : int skb_send_sock_locked(struct sock *sk, struct sk_buff *skb, int offset,
3624 : int len);
3625 : void skb_copy_and_csum_dev(const struct sk_buff *skb, u8 *to);
3626 : unsigned int skb_zerocopy_headlen(const struct sk_buff *from);
3627 : int skb_zerocopy(struct sk_buff *to, struct sk_buff *from,
3628 : int len, int hlen);
3629 : void skb_split(struct sk_buff *skb, struct sk_buff *skb1, const u32 len);
3630 : int skb_shift(struct sk_buff *tgt, struct sk_buff *skb, int shiftlen);
3631 : void skb_scrub_packet(struct sk_buff *skb, bool xnet);
3632 : bool skb_gso_validate_network_len(const struct sk_buff *skb, unsigned int mtu);
3633 : bool skb_gso_validate_mac_len(const struct sk_buff *skb, unsigned int len);
3634 : struct sk_buff *skb_segment(struct sk_buff *skb, netdev_features_t features);
3635 : struct sk_buff *skb_segment_list(struct sk_buff *skb, netdev_features_t features,
3636 : unsigned int offset);
3637 : struct sk_buff *skb_vlan_untag(struct sk_buff *skb);
3638 : int skb_ensure_writable(struct sk_buff *skb, int write_len);
3639 : int __skb_vlan_pop(struct sk_buff *skb, u16 *vlan_tci);
3640 : int skb_vlan_pop(struct sk_buff *skb);
3641 : int skb_vlan_push(struct sk_buff *skb, __be16 vlan_proto, u16 vlan_tci);
3642 : int skb_eth_pop(struct sk_buff *skb);
3643 : int skb_eth_push(struct sk_buff *skb, const unsigned char *dst,
3644 : const unsigned char *src);
3645 : int skb_mpls_push(struct sk_buff *skb, __be32 mpls_lse, __be16 mpls_proto,
3646 : int mac_len, bool ethernet);
3647 : int skb_mpls_pop(struct sk_buff *skb, __be16 next_proto, int mac_len,
3648 : bool ethernet);
3649 : int skb_mpls_update_lse(struct sk_buff *skb, __be32 mpls_lse);
3650 : int skb_mpls_dec_ttl(struct sk_buff *skb);
3651 : struct sk_buff *pskb_extract(struct sk_buff *skb, int off, int to_copy,
3652 : gfp_t gfp);
3653 :
3654 405 : static inline int memcpy_from_msg(void *data, struct msghdr *msg, int len)
3655 : {
3656 810 : return copy_from_iter_full(data, len, &msg->msg_iter) ? 0 : -EFAULT;
3657 : }
3658 :
3659 0 : static inline int memcpy_to_msg(struct msghdr *msg, void *data, int len)
3660 : {
3661 0 : return copy_to_iter(data, len, &msg->msg_iter) == len ? 0 : -EFAULT;
3662 : }
3663 :
3664 : struct skb_checksum_ops {
3665 : __wsum (*update)(const void *mem, int len, __wsum wsum);
3666 : __wsum (*combine)(__wsum csum, __wsum csum2, int offset, int len);
3667 : };
3668 :
3669 : extern const struct skb_checksum_ops *crc32c_csum_stub __read_mostly;
3670 :
3671 : __wsum __skb_checksum(const struct sk_buff *skb, int offset, int len,
3672 : __wsum csum, const struct skb_checksum_ops *ops);
3673 : __wsum skb_checksum(const struct sk_buff *skb, int offset, int len,
3674 : __wsum csum);
3675 :
3676 : static inline void * __must_check
3677 2 : __skb_header_pointer(const struct sk_buff *skb, int offset,
3678 : int len, void *data, int hlen, void *buffer)
3679 : {
3680 2 : if (hlen - offset >= len)
3681 2 : return data + offset;
3682 :
3683 0 : if (!skb ||
3684 0 : skb_copy_bits(skb, offset, buffer, len) < 0)
3685 0 : return NULL;
3686 :
3687 : return buffer;
3688 : }
3689 :
3690 : static inline void * __must_check
3691 0 : skb_header_pointer(const struct sk_buff *skb, int offset, int len, void *buffer)
3692 : {
3693 0 : return __skb_header_pointer(skb, offset, len, skb->data,
3694 0 : skb_headlen(skb), buffer);
3695 : }
3696 :
3697 : /**
3698 : * skb_needs_linearize - check if we need to linearize a given skb
3699 : * depending on the given device features.
3700 : * @skb: socket buffer to check
3701 : * @features: net device features
3702 : *
3703 : * Returns true if either:
3704 : * 1. skb has frag_list and the device doesn't support FRAGLIST, or
3705 : * 2. skb is fragmented and the device does not support SG.
3706 : */
3707 448 : static inline bool skb_needs_linearize(struct sk_buff *skb,
3708 : netdev_features_t features)
3709 : {
3710 448 : return skb_is_nonlinear(skb) &&
3711 361 : ((skb_has_frag_list(skb) && !(features & NETIF_F_FRAGLIST)) ||
3712 361 : (skb_shinfo(skb)->nr_frags && !(features & NETIF_F_SG)));
3713 : }
3714 :
3715 0 : static inline void skb_copy_from_linear_data(const struct sk_buff *skb,
3716 : void *to,
3717 : const unsigned int len)
3718 : {
3719 0 : memcpy(to, skb->data, len);
3720 : }
3721 :
3722 0 : static inline void skb_copy_from_linear_data_offset(const struct sk_buff *skb,
3723 : const int offset, void *to,
3724 : const unsigned int len)
3725 : {
3726 0 : memcpy(to, skb->data + offset, len);
3727 : }
3728 :
3729 : static inline void skb_copy_to_linear_data(struct sk_buff *skb,
3730 : const void *from,
3731 : const unsigned int len)
3732 : {
3733 : memcpy(skb->data, from, len);
3734 : }
3735 :
3736 0 : static inline void skb_copy_to_linear_data_offset(struct sk_buff *skb,
3737 : const int offset,
3738 : const void *from,
3739 : const unsigned int len)
3740 : {
3741 0 : memcpy(skb->data + offset, from, len);
3742 : }
3743 :
3744 : void skb_init(void);
3745 :
3746 : static inline ktime_t skb_get_ktime(const struct sk_buff *skb)
3747 : {
3748 : return skb->tstamp;
3749 : }
3750 :
3751 : /**
3752 : * skb_get_timestamp - get timestamp from a skb
3753 : * @skb: skb to get stamp from
3754 : * @stamp: pointer to struct __kernel_old_timeval to store stamp in
3755 : *
3756 : * Timestamps are stored in the skb as offsets to a base timestamp.
3757 : * This function converts the offset back to a struct timeval and stores
3758 : * it in stamp.
3759 : */
3760 511 : static inline void skb_get_timestamp(const struct sk_buff *skb,
3761 : struct __kernel_old_timeval *stamp)
3762 : {
3763 511 : *stamp = ns_to_kernel_old_timeval(skb->tstamp);
3764 : }
3765 :
3766 0 : static inline void skb_get_new_timestamp(const struct sk_buff *skb,
3767 : struct __kernel_sock_timeval *stamp)
3768 : {
3769 0 : struct timespec64 ts = ktime_to_timespec64(skb->tstamp);
3770 :
3771 0 : stamp->tv_sec = ts.tv_sec;
3772 0 : stamp->tv_usec = ts.tv_nsec / 1000;
3773 0 : }
3774 :
3775 0 : static inline void skb_get_timestampns(const struct sk_buff *skb,
3776 : struct __kernel_old_timespec *stamp)
3777 : {
3778 0 : struct timespec64 ts = ktime_to_timespec64(skb->tstamp);
3779 :
3780 0 : stamp->tv_sec = ts.tv_sec;
3781 0 : stamp->tv_nsec = ts.tv_nsec;
3782 0 : }
3783 :
3784 0 : static inline void skb_get_new_timestampns(const struct sk_buff *skb,
3785 : struct __kernel_timespec *stamp)
3786 : {
3787 0 : struct timespec64 ts = ktime_to_timespec64(skb->tstamp);
3788 :
3789 0 : stamp->tv_sec = ts.tv_sec;
3790 0 : stamp->tv_nsec = ts.tv_nsec;
3791 0 : }
3792 :
3793 511 : static inline void __net_timestamp(struct sk_buff *skb)
3794 : {
3795 511 : skb->tstamp = ktime_get_real();
3796 437 : }
3797 :
3798 : static inline ktime_t net_timedelta(ktime_t t)
3799 : {
3800 : return ktime_sub(ktime_get_real(), t);
3801 : }
3802 :
3803 : static inline ktime_t net_invalid_timestamp(void)
3804 : {
3805 : return 0;
3806 : }
3807 :
3808 269 : static inline u8 skb_metadata_len(const struct sk_buff *skb)
3809 : {
3810 269 : return skb_shinfo(skb)->meta_len;
3811 : }
3812 :
3813 0 : static inline void *skb_metadata_end(const struct sk_buff *skb)
3814 : {
3815 0 : return skb_mac_header(skb);
3816 : }
3817 :
3818 0 : static inline bool __skb_metadata_differs(const struct sk_buff *skb_a,
3819 : const struct sk_buff *skb_b,
3820 : u8 meta_len)
3821 : {
3822 0 : const void *a = skb_metadata_end(skb_a);
3823 0 : const void *b = skb_metadata_end(skb_b);
3824 : /* Using more efficient varaiant than plain call to memcmp(). */
3825 : #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
3826 0 : u64 diffs = 0;
3827 :
3828 0 : switch (meta_len) {
3829 : #define __it(x, op) (x -= sizeof(u##op))
3830 : #define __it_diff(a, b, op) (*(u##op *)__it(a, op)) ^ (*(u##op *)__it(b, op))
3831 0 : case 32: diffs |= __it_diff(a, b, 64);
3832 0 : fallthrough;
3833 0 : case 24: diffs |= __it_diff(a, b, 64);
3834 0 : fallthrough;
3835 0 : case 16: diffs |= __it_diff(a, b, 64);
3836 0 : fallthrough;
3837 0 : case 8: diffs |= __it_diff(a, b, 64);
3838 0 : break;
3839 0 : case 28: diffs |= __it_diff(a, b, 64);
3840 0 : fallthrough;
3841 0 : case 20: diffs |= __it_diff(a, b, 64);
3842 0 : fallthrough;
3843 0 : case 12: diffs |= __it_diff(a, b, 64);
3844 0 : fallthrough;
3845 0 : case 4: diffs |= __it_diff(a, b, 32);
3846 0 : break;
3847 : }
3848 0 : return diffs;
3849 : #else
3850 : return memcmp(a - meta_len, b - meta_len, meta_len);
3851 : #endif
3852 : }
3853 :
3854 269 : static inline bool skb_metadata_differs(const struct sk_buff *skb_a,
3855 : const struct sk_buff *skb_b)
3856 : {
3857 269 : u8 len_a = skb_metadata_len(skb_a);
3858 269 : u8 len_b = skb_metadata_len(skb_b);
3859 :
3860 269 : if (!(len_a | len_b))
3861 : return false;
3862 :
3863 0 : return len_a != len_b ?
3864 0 : true : __skb_metadata_differs(skb_a, skb_b, len_a);
3865 : }
3866 :
3867 374 : static inline void skb_metadata_set(struct sk_buff *skb, u8 meta_len)
3868 : {
3869 374 : skb_shinfo(skb)->meta_len = meta_len;
3870 0 : }
3871 :
3872 374 : static inline void skb_metadata_clear(struct sk_buff *skb)
3873 : {
3874 374 : skb_metadata_set(skb, 0);
3875 : }
3876 :
3877 : struct sk_buff *skb_clone_sk(struct sk_buff *skb);
3878 :
3879 : #ifdef CONFIG_NETWORK_PHY_TIMESTAMPING
3880 :
3881 : void skb_clone_tx_timestamp(struct sk_buff *skb);
3882 : bool skb_defer_rx_timestamp(struct sk_buff *skb);
3883 :
3884 : #else /* CONFIG_NETWORK_PHY_TIMESTAMPING */
3885 :
3886 448 : static inline void skb_clone_tx_timestamp(struct sk_buff *skb)
3887 : {
3888 448 : }
3889 :
3890 456 : static inline bool skb_defer_rx_timestamp(struct sk_buff *skb)
3891 : {
3892 456 : return false;
3893 : }
3894 :
3895 : #endif /* !CONFIG_NETWORK_PHY_TIMESTAMPING */
3896 :
3897 : /**
3898 : * skb_complete_tx_timestamp() - deliver cloned skb with tx timestamps
3899 : *
3900 : * PHY drivers may accept clones of transmitted packets for
3901 : * timestamping via their phy_driver.txtstamp method. These drivers
3902 : * must call this function to return the skb back to the stack with a
3903 : * timestamp.
3904 : *
3905 : * @skb: clone of the original outgoing packet
3906 : * @hwtstamps: hardware time stamps
3907 : *
3908 : */
3909 : void skb_complete_tx_timestamp(struct sk_buff *skb,
3910 : struct skb_shared_hwtstamps *hwtstamps);
3911 :
3912 : void __skb_tstamp_tx(struct sk_buff *orig_skb, const struct sk_buff *ack_skb,
3913 : struct skb_shared_hwtstamps *hwtstamps,
3914 : struct sock *sk, int tstype);
3915 :
3916 : /**
3917 : * skb_tstamp_tx - queue clone of skb with send time stamps
3918 : * @orig_skb: the original outgoing packet
3919 : * @hwtstamps: hardware time stamps, may be NULL if not available
3920 : *
3921 : * If the skb has a socket associated, then this function clones the
3922 : * skb (thus sharing the actual data and optional structures), stores
3923 : * the optional hardware time stamping information (if non NULL) or
3924 : * generates a software time stamp (otherwise), then queues the clone
3925 : * to the error queue of the socket. Errors are silently ignored.
3926 : */
3927 : void skb_tstamp_tx(struct sk_buff *orig_skb,
3928 : struct skb_shared_hwtstamps *hwtstamps);
3929 :
3930 : /**
3931 : * skb_tx_timestamp() - Driver hook for transmit timestamping
3932 : *
3933 : * Ethernet MAC Drivers should call this function in their hard_xmit()
3934 : * function immediately before giving the sk_buff to the MAC hardware.
3935 : *
3936 : * Specifically, one should make absolutely sure that this function is
3937 : * called before TX completion of this packet can trigger. Otherwise
3938 : * the packet could potentially already be freed.
3939 : *
3940 : * @skb: A socket buffer.
3941 : */
3942 448 : static inline void skb_tx_timestamp(struct sk_buff *skb)
3943 : {
3944 448 : skb_clone_tx_timestamp(skb);
3945 448 : if (skb_shinfo(skb)->tx_flags & SKBTX_SW_TSTAMP)
3946 0 : skb_tstamp_tx(skb, NULL);
3947 448 : }
3948 :
3949 : /**
3950 : * skb_complete_wifi_ack - deliver skb with wifi status
3951 : *
3952 : * @skb: the original outgoing packet
3953 : * @acked: ack status
3954 : *
3955 : */
3956 : void skb_complete_wifi_ack(struct sk_buff *skb, bool acked);
3957 :
3958 : __sum16 __skb_checksum_complete_head(struct sk_buff *skb, int len);
3959 : __sum16 __skb_checksum_complete(struct sk_buff *skb);
3960 :
3961 698 : static inline int skb_csum_unnecessary(const struct sk_buff *skb)
3962 : {
3963 271 : return ((skb->ip_summed == CHECKSUM_UNNECESSARY) ||
3964 727 : skb->csum_valid ||
3965 15 : (skb->ip_summed == CHECKSUM_PARTIAL &&
3966 15 : skb_checksum_start_offset(skb) >= 0));
3967 : }
3968 :
3969 : /**
3970 : * skb_checksum_complete - Calculate checksum of an entire packet
3971 : * @skb: packet to process
3972 : *
3973 : * This function calculates the checksum over the entire packet plus
3974 : * the value of skb->csum. The latter can be used to supply the
3975 : * checksum of a pseudo header as used by TCP/UDP. It returns the
3976 : * checksum.
3977 : *
3978 : * For protocols that contain complete checksums such as ICMP/TCP/UDP,
3979 : * this function can be used to verify that checksum on received
3980 : * packets. In that case the function should return zero if the
3981 : * checksum is correct. In particular, this function will return zero
3982 : * if skb->ip_summed is CHECKSUM_UNNECESSARY which indicates that the
3983 : * hardware has already verified the correctness of the checksum.
3984 : */
3985 : static inline __sum16 skb_checksum_complete(struct sk_buff *skb)
3986 : {
3987 : return skb_csum_unnecessary(skb) ?
3988 : 0 : __skb_checksum_complete(skb);
3989 : }
3990 :
3991 440 : static inline void __skb_decr_checksum_unnecessary(struct sk_buff *skb)
3992 : {
3993 440 : if (skb->ip_summed == CHECKSUM_UNNECESSARY) {
3994 425 : if (skb->csum_level == 0)
3995 425 : skb->ip_summed = CHECKSUM_NONE;
3996 : else
3997 0 : skb->csum_level--;
3998 : }
3999 440 : }
4000 :
4001 707 : static inline void __skb_incr_checksum_unnecessary(struct sk_buff *skb)
4002 : {
4003 707 : if (skb->ip_summed == CHECKSUM_UNNECESSARY) {
4004 0 : if (skb->csum_level < SKB_MAX_CSUM_LEVEL)
4005 0 : skb->csum_level++;
4006 707 : } else if (skb->ip_summed == CHECKSUM_NONE) {
4007 707 : skb->ip_summed = CHECKSUM_UNNECESSARY;
4008 707 : skb->csum_level = 0;
4009 : }
4010 707 : }
4011 :
4012 0 : static inline void __skb_reset_checksum_unnecessary(struct sk_buff *skb)
4013 : {
4014 0 : if (skb->ip_summed == CHECKSUM_UNNECESSARY) {
4015 0 : skb->ip_summed = CHECKSUM_NONE;
4016 0 : skb->csum_level = 0;
4017 : }
4018 : }
4019 :
4020 : /* Check if we need to perform checksum complete validation.
4021 : *
4022 : * Returns true if checksum complete is needed, false otherwise
4023 : * (either checksum is unnecessary or zero checksum is allowed).
4024 : */
4025 454 : static inline bool __skb_checksum_validate_needed(struct sk_buff *skb,
4026 : bool zero_okay,
4027 : __sum16 check)
4028 : {
4029 454 : if (skb_csum_unnecessary(skb) || (zero_okay && !check)) {
4030 440 : skb->csum_valid = 1;
4031 440 : __skb_decr_checksum_unnecessary(skb);
4032 440 : return false;
4033 : }
4034 :
4035 : return true;
4036 : }
4037 :
4038 : /* For small packets <= CHECKSUM_BREAK perform checksum complete directly
4039 : * in checksum_init.
4040 : */
4041 : #define CHECKSUM_BREAK 76
4042 :
4043 : /* Unset checksum-complete
4044 : *
4045 : * Unset checksum complete can be done when packet is being modified
4046 : * (uncompressed for instance) and checksum-complete value is
4047 : * invalidated.
4048 : */
4049 0 : static inline void skb_checksum_complete_unset(struct sk_buff *skb)
4050 : {
4051 0 : if (skb->ip_summed == CHECKSUM_COMPLETE)
4052 0 : skb->ip_summed = CHECKSUM_NONE;
4053 : }
4054 :
4055 : /* Validate (init) checksum based on checksum complete.
4056 : *
4057 : * Return values:
4058 : * 0: checksum is validated or try to in skb_checksum_complete. In the latter
4059 : * case the ip_summed will not be CHECKSUM_UNNECESSARY and the pseudo
4060 : * checksum is stored in skb->csum for use in __skb_checksum_complete
4061 : * non-zero: value of invalid checksum
4062 : *
4063 : */
4064 14 : static inline __sum16 __skb_checksum_validate_complete(struct sk_buff *skb,
4065 : bool complete,
4066 : __wsum psum)
4067 : {
4068 14 : if (skb->ip_summed == CHECKSUM_COMPLETE) {
4069 0 : if (!csum_fold(csum_add(psum, skb->csum))) {
4070 0 : skb->csum_valid = 1;
4071 0 : return 0;
4072 : }
4073 : }
4074 :
4075 14 : skb->csum = psum;
4076 :
4077 14 : if (complete || skb->len <= CHECKSUM_BREAK) {
4078 14 : __sum16 csum;
4079 :
4080 14 : csum = __skb_checksum_complete(skb);
4081 14 : skb->csum_valid = !csum;
4082 14 : return csum;
4083 : }
4084 :
4085 : return 0;
4086 : }
4087 :
4088 14 : static inline __wsum null_compute_pseudo(struct sk_buff *skb, int proto)
4089 : {
4090 14 : return 0;
4091 : }
4092 :
4093 : /* Perform checksum validate (init). Note that this is a macro since we only
4094 : * want to calculate the pseudo header which is an input function if necessary.
4095 : * First we try to validate without any computation (checksum unnecessary) and
4096 : * then calculate based on checksum complete calling the function to compute
4097 : * pseudo header.
4098 : *
4099 : * Return values:
4100 : * 0: checksum is validated or try to in skb_checksum_complete
4101 : * non-zero: value of invalid checksum
4102 : */
4103 : #define __skb_checksum_validate(skb, proto, complete, \
4104 : zero_okay, check, compute_pseudo) \
4105 : ({ \
4106 : __sum16 __ret = 0; \
4107 : skb->csum_valid = 0; \
4108 : if (__skb_checksum_validate_needed(skb, zero_okay, check)) \
4109 : __ret = __skb_checksum_validate_complete(skb, \
4110 : complete, compute_pseudo(skb, proto)); \
4111 : __ret; \
4112 : })
4113 :
4114 : #define skb_checksum_init(skb, proto, compute_pseudo) \
4115 : __skb_checksum_validate(skb, proto, false, false, 0, compute_pseudo)
4116 :
4117 : #define skb_checksum_init_zero_check(skb, proto, check, compute_pseudo) \
4118 : __skb_checksum_validate(skb, proto, false, true, check, compute_pseudo)
4119 :
4120 : #define skb_checksum_validate(skb, proto, compute_pseudo) \
4121 : __skb_checksum_validate(skb, proto, true, false, 0, compute_pseudo)
4122 :
4123 : #define skb_checksum_validate_zero_check(skb, proto, check, \
4124 : compute_pseudo) \
4125 : __skb_checksum_validate(skb, proto, true, true, check, compute_pseudo)
4126 :
4127 : #define skb_checksum_simple_validate(skb) \
4128 : __skb_checksum_validate(skb, 0, true, false, 0, null_compute_pseudo)
4129 :
4130 0 : static inline bool __skb_checksum_convert_check(struct sk_buff *skb)
4131 : {
4132 0 : return (skb->ip_summed == CHECKSUM_NONE && skb->csum_valid);
4133 : }
4134 :
4135 0 : static inline void __skb_checksum_convert(struct sk_buff *skb, __wsum pseudo)
4136 : {
4137 0 : skb->csum = ~pseudo;
4138 0 : skb->ip_summed = CHECKSUM_COMPLETE;
4139 0 : }
4140 :
4141 : #define skb_checksum_try_convert(skb, proto, compute_pseudo) \
4142 : do { \
4143 : if (__skb_checksum_convert_check(skb)) \
4144 : __skb_checksum_convert(skb, compute_pseudo(skb, proto)); \
4145 : } while (0)
4146 :
4147 : static inline void skb_remcsum_adjust_partial(struct sk_buff *skb, void *ptr,
4148 : u16 start, u16 offset)
4149 : {
4150 : skb->ip_summed = CHECKSUM_PARTIAL;
4151 : skb->csum_start = ((unsigned char *)ptr + start) - skb->head;
4152 : skb->csum_offset = offset - start;
4153 : }
4154 :
4155 : /* Update skbuf and packet to reflect the remote checksum offload operation.
4156 : * When called, ptr indicates the starting point for skb->csum when
4157 : * ip_summed is CHECKSUM_COMPLETE. If we need create checksum complete
4158 : * here, skb_postpull_rcsum is done so skb->csum start is ptr.
4159 : */
4160 : static inline void skb_remcsum_process(struct sk_buff *skb, void *ptr,
4161 : int start, int offset, bool nopartial)
4162 : {
4163 : __wsum delta;
4164 :
4165 : if (!nopartial) {
4166 : skb_remcsum_adjust_partial(skb, ptr, start, offset);
4167 : return;
4168 : }
4169 :
4170 : if (unlikely(skb->ip_summed != CHECKSUM_COMPLETE)) {
4171 : __skb_checksum_complete(skb);
4172 : skb_postpull_rcsum(skb, skb->data, ptr - (void *)skb->data);
4173 : }
4174 :
4175 : delta = remcsum_adjust(ptr, skb->csum, start, offset);
4176 :
4177 : /* Adjust skb->csum since we changed the packet */
4178 : skb->csum = csum_add(skb->csum, delta);
4179 : }
4180 :
4181 : static inline struct nf_conntrack *skb_nfct(const struct sk_buff *skb)
4182 : {
4183 : #if IS_ENABLED(CONFIG_NF_CONNTRACK)
4184 : return (void *)(skb->_nfct & NFCT_PTRMASK);
4185 : #else
4186 : return NULL;
4187 : #endif
4188 : }
4189 :
4190 : static inline unsigned long skb_get_nfct(const struct sk_buff *skb)
4191 : {
4192 : #if IS_ENABLED(CONFIG_NF_CONNTRACK)
4193 : return skb->_nfct;
4194 : #else
4195 : return 0UL;
4196 : #endif
4197 : }
4198 :
4199 : static inline void skb_set_nfct(struct sk_buff *skb, unsigned long nfct)
4200 : {
4201 : #if IS_ENABLED(CONFIG_NF_CONNTRACK)
4202 : skb->_nfct = nfct;
4203 : #endif
4204 : }
4205 :
4206 : #ifdef CONFIG_SKB_EXTENSIONS
4207 : enum skb_ext_id {
4208 : #if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
4209 : SKB_EXT_BRIDGE_NF,
4210 : #endif
4211 : #ifdef CONFIG_XFRM
4212 : SKB_EXT_SEC_PATH,
4213 : #endif
4214 : #if IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
4215 : TC_SKB_EXT,
4216 : #endif
4217 : #if IS_ENABLED(CONFIG_MPTCP)
4218 : SKB_EXT_MPTCP,
4219 : #endif
4220 : SKB_EXT_NUM, /* must be last */
4221 : };
4222 :
4223 : /**
4224 : * struct skb_ext - sk_buff extensions
4225 : * @refcnt: 1 on allocation, deallocated on 0
4226 : * @offset: offset to add to @data to obtain extension address
4227 : * @chunks: size currently allocated, stored in SKB_EXT_ALIGN_SHIFT units
4228 : * @data: start of extension data, variable sized
4229 : *
4230 : * Note: offsets/lengths are stored in chunks of 8 bytes, this allows
4231 : * to use 'u8' types while allowing up to 2kb worth of extension data.
4232 : */
4233 : struct skb_ext {
4234 : refcount_t refcnt;
4235 : u8 offset[SKB_EXT_NUM]; /* in chunks of 8 bytes */
4236 : u8 chunks; /* same */
4237 : char data[] __aligned(8);
4238 : };
4239 :
4240 : struct skb_ext *__skb_ext_alloc(gfp_t flags);
4241 : void *__skb_ext_set(struct sk_buff *skb, enum skb_ext_id id,
4242 : struct skb_ext *ext);
4243 : void *skb_ext_add(struct sk_buff *skb, enum skb_ext_id id);
4244 : void __skb_ext_del(struct sk_buff *skb, enum skb_ext_id id);
4245 : void __skb_ext_put(struct skb_ext *ext);
4246 :
4247 : static inline void skb_ext_put(struct sk_buff *skb)
4248 : {
4249 : if (skb->active_extensions)
4250 : __skb_ext_put(skb->extensions);
4251 : }
4252 :
4253 : static inline void __skb_ext_copy(struct sk_buff *dst,
4254 : const struct sk_buff *src)
4255 : {
4256 : dst->active_extensions = src->active_extensions;
4257 :
4258 : if (src->active_extensions) {
4259 : struct skb_ext *ext = src->extensions;
4260 :
4261 : refcount_inc(&ext->refcnt);
4262 : dst->extensions = ext;
4263 : }
4264 : }
4265 :
4266 : static inline void skb_ext_copy(struct sk_buff *dst, const struct sk_buff *src)
4267 : {
4268 : skb_ext_put(dst);
4269 : __skb_ext_copy(dst, src);
4270 : }
4271 :
4272 : static inline bool __skb_ext_exist(const struct skb_ext *ext, enum skb_ext_id i)
4273 : {
4274 : return !!ext->offset[i];
4275 : }
4276 :
4277 : static inline bool skb_ext_exist(const struct sk_buff *skb, enum skb_ext_id id)
4278 : {
4279 : return skb->active_extensions & (1 << id);
4280 : }
4281 :
4282 : static inline void skb_ext_del(struct sk_buff *skb, enum skb_ext_id id)
4283 : {
4284 : if (skb_ext_exist(skb, id))
4285 : __skb_ext_del(skb, id);
4286 : }
4287 :
4288 : static inline void *skb_ext_find(const struct sk_buff *skb, enum skb_ext_id id)
4289 : {
4290 : if (skb_ext_exist(skb, id)) {
4291 : struct skb_ext *ext = skb->extensions;
4292 :
4293 : return (void *)ext + (ext->offset[id] << 3);
4294 : }
4295 :
4296 : return NULL;
4297 : }
4298 :
4299 : static inline void skb_ext_reset(struct sk_buff *skb)
4300 : {
4301 : if (unlikely(skb->active_extensions)) {
4302 : __skb_ext_put(skb->extensions);
4303 : skb->active_extensions = 0;
4304 : }
4305 : }
4306 :
4307 : static inline bool skb_has_extensions(struct sk_buff *skb)
4308 : {
4309 : return unlikely(skb->active_extensions);
4310 : }
4311 : #else
4312 0 : static inline void skb_ext_put(struct sk_buff *skb) {}
4313 0 : static inline void skb_ext_reset(struct sk_buff *skb) {}
4314 : static inline void skb_ext_del(struct sk_buff *skb, int unused) {}
4315 1184 : static inline void __skb_ext_copy(struct sk_buff *d, const struct sk_buff *s) {}
4316 0 : static inline void skb_ext_copy(struct sk_buff *dst, const struct sk_buff *s) {}
4317 2 : static inline bool skb_has_extensions(struct sk_buff *skb) { return false; }
4318 : #endif /* CONFIG_SKB_EXTENSIONS */
4319 :
4320 438 : static inline void nf_reset_ct(struct sk_buff *skb)
4321 : {
4322 : #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
4323 : nf_conntrack_put(skb_nfct(skb));
4324 : skb->_nfct = 0;
4325 : #endif
4326 438 : }
4327 :
4328 0 : static inline void nf_reset_trace(struct sk_buff *skb)
4329 : {
4330 : #if IS_ENABLED(CONFIG_NETFILTER_XT_TARGET_TRACE) || defined(CONFIG_NF_TABLES)
4331 : skb->nf_trace = 0;
4332 : #endif
4333 0 : }
4334 :
4335 0 : static inline void ipvs_reset(struct sk_buff *skb)
4336 : {
4337 : #if IS_ENABLED(CONFIG_IP_VS)
4338 : skb->ipvs_property = 0;
4339 : #endif
4340 0 : }
4341 :
4342 : /* Note: This doesn't put any conntrack info in dst. */
4343 1184 : static inline void __nf_copy(struct sk_buff *dst, const struct sk_buff *src,
4344 : bool copy)
4345 : {
4346 : #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
4347 : dst->_nfct = src->_nfct;
4348 : nf_conntrack_get(skb_nfct(src));
4349 : #endif
4350 : #if IS_ENABLED(CONFIG_NETFILTER_XT_TARGET_TRACE) || defined(CONFIG_NF_TABLES)
4351 : if (copy)
4352 : dst->nf_trace = src->nf_trace;
4353 : #endif
4354 1184 : }
4355 :
4356 0 : static inline void nf_copy(struct sk_buff *dst, const struct sk_buff *src)
4357 : {
4358 : #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
4359 : nf_conntrack_put(skb_nfct(dst));
4360 : #endif
4361 0 : __nf_copy(dst, src, true);
4362 : }
4363 :
4364 : #ifdef CONFIG_NETWORK_SECMARK
4365 : static inline void skb_copy_secmark(struct sk_buff *to, const struct sk_buff *from)
4366 : {
4367 : to->secmark = from->secmark;
4368 : }
4369 :
4370 : static inline void skb_init_secmark(struct sk_buff *skb)
4371 : {
4372 : skb->secmark = 0;
4373 : }
4374 : #else
4375 0 : static inline void skb_copy_secmark(struct sk_buff *to, const struct sk_buff *from)
4376 0 : { }
4377 :
4378 : static inline void skb_init_secmark(struct sk_buff *skb)
4379 : { }
4380 : #endif
4381 :
4382 73 : static inline int secpath_exists(const struct sk_buff *skb)
4383 : {
4384 : #ifdef CONFIG_XFRM
4385 : return skb_ext_exist(skb, SKB_EXT_SEC_PATH);
4386 : #else
4387 73 : return 0;
4388 : #endif
4389 : }
4390 :
4391 : static inline bool skb_irq_freeable(const struct sk_buff *skb)
4392 : {
4393 : return !skb->destructor &&
4394 : !secpath_exists(skb) &&
4395 : !skb_nfct(skb) &&
4396 : !skb->_skb_refdst &&
4397 : !skb_has_frag_list(skb);
4398 : }
4399 :
4400 448 : static inline void skb_set_queue_mapping(struct sk_buff *skb, u16 queue_mapping)
4401 : {
4402 0 : skb->queue_mapping = queue_mapping;
4403 : }
4404 :
4405 896 : static inline u16 skb_get_queue_mapping(const struct sk_buff *skb)
4406 : {
4407 896 : return skb->queue_mapping;
4408 : }
4409 :
4410 : static inline void skb_copy_queue_mapping(struct sk_buff *to, const struct sk_buff *from)
4411 : {
4412 : to->queue_mapping = from->queue_mapping;
4413 : }
4414 :
4415 723 : static inline void skb_record_rx_queue(struct sk_buff *skb, u16 rx_queue)
4416 : {
4417 723 : skb->queue_mapping = rx_queue + 1;
4418 : }
4419 :
4420 420 : static inline u16 skb_get_rx_queue(const struct sk_buff *skb)
4421 : {
4422 420 : return skb->queue_mapping - 1;
4423 : }
4424 :
4425 420 : static inline bool skb_rx_queue_recorded(const struct sk_buff *skb)
4426 : {
4427 420 : return skb->queue_mapping != 0;
4428 : }
4429 :
4430 426 : static inline void skb_set_dst_pending_confirm(struct sk_buff *skb, u32 val)
4431 : {
4432 426 : skb->dst_pending_confirm = val;
4433 0 : }
4434 :
4435 444 : static inline bool skb_get_dst_pending_confirm(const struct sk_buff *skb)
4436 : {
4437 444 : return skb->dst_pending_confirm != 0;
4438 : }
4439 :
4440 0 : static inline struct sec_path *skb_sec_path(const struct sk_buff *skb)
4441 : {
4442 : #ifdef CONFIG_XFRM
4443 : return skb_ext_find(skb, SKB_EXT_SEC_PATH);
4444 : #else
4445 0 : return NULL;
4446 : #endif
4447 : }
4448 :
4449 : /* Keeps track of mac header offset relative to skb->head.
4450 : * It is useful for TSO of Tunneling protocol. e.g. GRE.
4451 : * For non-tunnel skb it points to skb_mac_header() and for
4452 : * tunnel skb it points to outer mac header.
4453 : * Keeps track of level of encapsulation of network headers.
4454 : */
4455 : struct skb_gso_cb {
4456 : union {
4457 : int mac_offset;
4458 : int data_offset;
4459 : };
4460 : int encap_level;
4461 : __wsum csum;
4462 : __u16 csum_start;
4463 : };
4464 : #define SKB_GSO_CB_OFFSET 32
4465 : #define SKB_GSO_CB(skb) ((struct skb_gso_cb *)((skb)->cb + SKB_GSO_CB_OFFSET))
4466 :
4467 0 : static inline int skb_tnl_header_len(const struct sk_buff *inner_skb)
4468 : {
4469 0 : return (skb_mac_header(inner_skb) - inner_skb->head) -
4470 0 : SKB_GSO_CB(inner_skb)->mac_offset;
4471 : }
4472 :
4473 : static inline int gso_pskb_expand_head(struct sk_buff *skb, int extra)
4474 : {
4475 : int new_headroom, headroom;
4476 : int ret;
4477 :
4478 : headroom = skb_headroom(skb);
4479 : ret = pskb_expand_head(skb, extra, 0, GFP_ATOMIC);
4480 : if (ret)
4481 : return ret;
4482 :
4483 : new_headroom = skb_headroom(skb);
4484 : SKB_GSO_CB(skb)->mac_offset += (new_headroom - headroom);
4485 : return 0;
4486 : }
4487 :
4488 0 : static inline void gso_reset_checksum(struct sk_buff *skb, __wsum res)
4489 : {
4490 : /* Do not update partial checksums if remote checksum is enabled. */
4491 0 : if (skb->remcsum_offload)
4492 : return;
4493 :
4494 0 : SKB_GSO_CB(skb)->csum = res;
4495 0 : SKB_GSO_CB(skb)->csum_start = skb_checksum_start(skb) - skb->head;
4496 : }
4497 :
4498 : /* Compute the checksum for a gso segment. First compute the checksum value
4499 : * from the start of transport header to SKB_GSO_CB(skb)->csum_start, and
4500 : * then add in skb->csum (checksum from csum_start to end of packet).
4501 : * skb->csum and csum_start are then updated to reflect the checksum of the
4502 : * resultant packet starting from the transport header-- the resultant checksum
4503 : * is in the res argument (i.e. normally zero or ~ of checksum of a pseudo
4504 : * header.
4505 : */
4506 0 : static inline __sum16 gso_make_checksum(struct sk_buff *skb, __wsum res)
4507 : {
4508 0 : unsigned char *csum_start = skb_transport_header(skb);
4509 0 : int plen = (skb->head + SKB_GSO_CB(skb)->csum_start) - csum_start;
4510 0 : __wsum partial = SKB_GSO_CB(skb)->csum;
4511 :
4512 0 : SKB_GSO_CB(skb)->csum = res;
4513 0 : SKB_GSO_CB(skb)->csum_start = csum_start - skb->head;
4514 :
4515 0 : return csum_fold(csum_partial(csum_start, plen, partial));
4516 : }
4517 :
4518 3388 : static inline bool skb_is_gso(const struct sk_buff *skb)
4519 : {
4520 3388 : return skb_shinfo(skb)->gso_size;
4521 : }
4522 :
4523 : /* Note: Should be called only if skb_is_gso(skb) is true */
4524 : static inline bool skb_is_gso_v6(const struct sk_buff *skb)
4525 : {
4526 : return skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6;
4527 : }
4528 :
4529 : /* Note: Should be called only if skb_is_gso(skb) is true */
4530 0 : static inline bool skb_is_gso_sctp(const struct sk_buff *skb)
4531 : {
4532 0 : return skb_shinfo(skb)->gso_type & SKB_GSO_SCTP;
4533 : }
4534 :
4535 : /* Note: Should be called only if skb_is_gso(skb) is true */
4536 0 : static inline bool skb_is_gso_tcp(const struct sk_buff *skb)
4537 : {
4538 0 : return skb_shinfo(skb)->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6);
4539 : }
4540 :
4541 0 : static inline void skb_gso_reset(struct sk_buff *skb)
4542 : {
4543 0 : skb_shinfo(skb)->gso_size = 0;
4544 0 : skb_shinfo(skb)->gso_segs = 0;
4545 0 : skb_shinfo(skb)->gso_type = 0;
4546 0 : }
4547 :
4548 0 : static inline void skb_increase_gso_size(struct skb_shared_info *shinfo,
4549 : u16 increment)
4550 : {
4551 0 : if (WARN_ON_ONCE(shinfo->gso_size == GSO_BY_FRAGS))
4552 : return;
4553 0 : shinfo->gso_size += increment;
4554 : }
4555 :
4556 0 : static inline void skb_decrease_gso_size(struct skb_shared_info *shinfo,
4557 : u16 decrement)
4558 : {
4559 0 : if (WARN_ON_ONCE(shinfo->gso_size == GSO_BY_FRAGS))
4560 : return;
4561 0 : shinfo->gso_size -= decrement;
4562 : }
4563 :
4564 : void __skb_warn_lro_forwarding(const struct sk_buff *skb);
4565 :
4566 0 : static inline bool skb_warn_if_lro(const struct sk_buff *skb)
4567 : {
4568 : /* LRO sets gso_size but not gso_type, whereas if GSO is really
4569 : * wanted then gso_type will be set. */
4570 0 : const struct skb_shared_info *shinfo = skb_shinfo(skb);
4571 :
4572 0 : if (skb_is_nonlinear(skb) && shinfo->gso_size != 0 &&
4573 0 : unlikely(shinfo->gso_type == 0)) {
4574 0 : __skb_warn_lro_forwarding(skb);
4575 0 : return true;
4576 : }
4577 : return false;
4578 : }
4579 :
4580 0 : static inline void skb_forward_csum(struct sk_buff *skb)
4581 : {
4582 : /* Unfortunately we don't support this one. Any brave souls? */
4583 0 : if (skb->ip_summed == CHECKSUM_COMPLETE)
4584 0 : skb->ip_summed = CHECKSUM_NONE;
4585 : }
4586 :
4587 : /**
4588 : * skb_checksum_none_assert - make sure skb ip_summed is CHECKSUM_NONE
4589 : * @skb: skb to check
4590 : *
4591 : * fresh skbs have their ip_summed set to CHECKSUM_NONE.
4592 : * Instead of forcing ip_summed to CHECKSUM_NONE, we can
4593 : * use this helper, to document places where we make this assertion.
4594 : */
4595 : static inline void skb_checksum_none_assert(const struct sk_buff *skb)
4596 : {
4597 : #ifdef DEBUG
4598 : BUG_ON(skb->ip_summed != CHECKSUM_NONE);
4599 : #endif
4600 : }
4601 :
4602 : bool skb_partial_csum_set(struct sk_buff *skb, u16 start, u16 off);
4603 :
4604 : int skb_checksum_setup(struct sk_buff *skb, bool recalculate);
4605 : struct sk_buff *skb_checksum_trimmed(struct sk_buff *skb,
4606 : unsigned int transport_len,
4607 : __sum16(*skb_chkf)(struct sk_buff *skb));
4608 :
4609 : /**
4610 : * skb_head_is_locked - Determine if the skb->head is locked down
4611 : * @skb: skb to check
4612 : *
4613 : * The head on skbs build around a head frag can be removed if they are
4614 : * not cloned. This function returns true if the skb head is locked down
4615 : * due to either being allocated via kmalloc, or by being a clone with
4616 : * multiple references to the head.
4617 : */
4618 2 : static inline bool skb_head_is_locked(const struct sk_buff *skb)
4619 : {
4620 2 : return !skb->head_frag || skb_cloned(skb);
4621 : }
4622 :
4623 : /* Local Checksum Offload.
4624 : * Compute outer checksum based on the assumption that the
4625 : * inner checksum will be offloaded later.
4626 : * See Documentation/networking/checksum-offloads.rst for
4627 : * explanation of how this works.
4628 : * Fill in outer checksum adjustment (e.g. with sum of outer
4629 : * pseudo-header) before calling.
4630 : * Also ensure that inner checksum is in linear data area.
4631 : */
4632 0 : static inline __wsum lco_csum(struct sk_buff *skb)
4633 : {
4634 0 : unsigned char *csum_start = skb_checksum_start(skb);
4635 0 : unsigned char *l4_hdr = skb_transport_header(skb);
4636 0 : __wsum partial;
4637 :
4638 : /* Start with complement of inner checksum adjustment */
4639 0 : partial = ~csum_unfold(*(__force __sum16 *)(csum_start +
4640 0 : skb->csum_offset));
4641 :
4642 : /* Add in checksum of our headers (incl. outer checksum
4643 : * adjustment filled in by caller) and return result.
4644 : */
4645 0 : return csum_partial(l4_hdr, csum_start - l4_hdr, partial);
4646 : }
4647 :
4648 0 : static inline bool skb_is_redirected(const struct sk_buff *skb)
4649 : {
4650 : #ifdef CONFIG_NET_REDIRECT
4651 : return skb->redirected;
4652 : #else
4653 0 : return false;
4654 : #endif
4655 : }
4656 :
4657 : static inline void skb_set_redirected(struct sk_buff *skb, bool from_ingress)
4658 : {
4659 : #ifdef CONFIG_NET_REDIRECT
4660 : skb->redirected = 1;
4661 : skb->from_ingress = from_ingress;
4662 : if (skb->from_ingress)
4663 : skb->tstamp = 0;
4664 : #endif
4665 : }
4666 :
4667 456 : static inline void skb_reset_redirect(struct sk_buff *skb)
4668 : {
4669 : #ifdef CONFIG_NET_REDIRECT
4670 : skb->redirected = 0;
4671 : #endif
4672 456 : }
4673 :
4674 430 : static inline bool skb_csum_is_sctp(struct sk_buff *skb)
4675 : {
4676 430 : return skb->csum_not_inet;
4677 : }
4678 :
4679 4864 : static inline void skb_set_kcov_handle(struct sk_buff *skb,
4680 : const u64 kcov_handle)
4681 : {
4682 : #ifdef CONFIG_KCOV
4683 : skb->kcov_handle = kcov_handle;
4684 : #endif
4685 4864 : }
4686 :
4687 : static inline u64 skb_get_kcov_handle(struct sk_buff *skb)
4688 : {
4689 : #ifdef CONFIG_KCOV
4690 : return skb->kcov_handle;
4691 : #else
4692 : return 0;
4693 : #endif
4694 : }
4695 :
4696 : #endif /* __KERNEL__ */
4697 : #endif /* _LINUX_SKBUFF_H */
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