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Commit | Line | Data |
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718e3744 | 1 | /* |
2 | * Packet interface | |
3 | * Copyright (C) 1999 Kunihiro Ishiguro | |
4 | * | |
5 | * This file is part of GNU Zebra. | |
6 | * | |
7 | * GNU Zebra is free software; you can redistribute it and/or modify it | |
8 | * under the terms of the GNU General Public License as published by the | |
9 | * Free Software Foundation; either version 2, or (at your option) any | |
10 | * later version. | |
11 | * | |
12 | * GNU Zebra is distributed in the hope that it will be useful, but | |
13 | * WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
15 | * General Public License for more details. | |
16 | * | |
896014f4 DL |
17 | * You should have received a copy of the GNU General Public License along |
18 | * with this program; see the file COPYING; if not, write to the Free Software | |
19 | * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA | |
718e3744 | 20 | */ |
21 | ||
22 | #ifndef _ZEBRA_STREAM_H | |
23 | #define _ZEBRA_STREAM_H | |
24 | ||
363e24c6 QY |
25 | #include <pthread.h> |
26 | ||
27 | #include "frratomic.h" | |
9bedbb1e | 28 | #include "mpls.h" |
02ff83c5 | 29 | #include "prefix.h" |
30 | ||
5e244469 RW |
31 | #ifdef __cplusplus |
32 | extern "C" { | |
33 | #endif | |
34 | ||
050c013a | 35 | /* |
36 | * A stream is an arbitrary buffer, whose contents generally are assumed to | |
37 | * be in network order. | |
38 | * | |
39 | * A stream has the following attributes associated with it: | |
40 | * | |
41 | * - size: the allocated, invariant size of the buffer. | |
42 | * | |
43 | * - getp: the get position marker, denoting the offset in the stream where | |
44 | * the next read (or 'get') will be from. This getp marker is | |
45 | * automatically adjusted when data is read from the stream, the | |
46 | * user may also manipulate this offset as they wish, within limits | |
47 | * (see below) | |
48 | * | |
49 | * - endp: the end position marker, denoting the offset in the stream where | |
50 | * valid data ends, and if the user attempted to write (or | |
51 | * 'put') data where that data would be written (or 'put') to. | |
52 | * | |
53 | * These attributes are all size_t values. | |
54 | * | |
55 | * Constraints: | |
56 | * | |
57 | * 1. getp can never exceed endp | |
58 | * | |
59 | * - hence if getp is equal to endp, there is no more valid data that can be | |
60 | * gotten from the stream (though, the user may reposition getp to earlier in | |
61 | * the stream, if they wish). | |
62 | * | |
63 | * 2. endp can never exceed size | |
64 | * | |
65 | * - hence, if endp is equal to size, then the stream is full, and no more | |
66 | * data can be written to the stream. | |
67 | * | |
68 | * In other words the following must always be true, and the stream | |
69 | * abstraction is allowed internally to assert that the following property | |
70 | * holds true for a stream, as and when it wishes: | |
71 | * | |
72 | * getp <= endp <= size | |
73 | * | |
74 | * It is the users responsibility to ensure this property is never violated. | |
75 | * | |
76 | * A stream therefore can be thought of like this: | |
77 | * | |
78 | * --------------------------------------------------- | |
79 | * |XXXXXXXXXXXXXXXXXXXXXXXX | | |
80 | * --------------------------------------------------- | |
81 | * ^ ^ ^ | |
82 | * getp endp size | |
83 | * | |
84 | * This shows a stream containing data (shown as 'X') up to the endp offset. | |
85 | * The stream is empty from endp to size. Without adjusting getp, there are | |
86 | * still endp-getp bytes of valid data to be read from the stream. | |
87 | * | |
d62a17ae | 88 | * Methods are provided to get and put to/from the stream, as well as |
050c013a | 89 | * retrieve the values of the 3 markers and manipulate the getp marker. |
90 | * | |
91 | * Note: | |
92 | * At the moment, newly allocated streams are zero filled. Hence, one can | |
93 | * use stream_forward_endp() to effectively create arbitrary zero-fill | |
94 | * padding. However, note that stream_reset() does *not* zero-out the | |
95 | * stream. This property should **not** be relied upon. | |
0dab9303 | 96 | * |
97 | * Best practice is to use stream_put (<stream *>, NULL, <size>) to zero out | |
98 | * any part of a stream which isn't otherwise written to. | |
050c013a | 99 | */ |
100 | ||
718e3744 | 101 | /* Stream buffer. */ |
d62a17ae | 102 | struct stream { |
103 | struct stream *next; | |
104 | ||
de75223e DS |
105 | /* |
106 | * Remainder is ***private*** to stream | |
d62a17ae | 107 | * direct access is frowned upon! |
108 | * Use the appropriate functions/macros | |
109 | */ | |
de75223e DS |
110 | size_t getp; /* next get position */ |
111 | size_t endp; /* last valid data position */ | |
112 | size_t size; /* size of data segment */ | |
83e7e1d7 | 113 | unsigned char data[]; /* data pointer */ |
718e3744 | 114 | }; |
115 | ||
116 | /* First in first out queue structure. */ | |
d62a17ae | 117 | struct stream_fifo { |
363e24c6 QY |
118 | /* lock for mt-safe operations */ |
119 | pthread_mutex_t mtx; | |
120 | ||
121 | /* number of streams in this fifo */ | |
c8a65463 | 122 | atomic_size_t count; |
03ed85a6 | 123 | #if defined DEV_BUILD |
c8a65463 | 124 | atomic_size_t max_count; |
03ed85a6 | 125 | #endif |
718e3744 | 126 | |
d62a17ae | 127 | struct stream *head; |
128 | struct stream *tail; | |
718e3744 | 129 | }; |
130 | ||
131 | /* Utility macros. */ | |
718e3744 | 132 | #define STREAM_SIZE(S) ((S)->size) |
d62a17ae | 133 | /* number of bytes which can still be written */ |
050c013a | 134 | #define STREAM_WRITEABLE(S) ((S)->size - (S)->endp) |
d62a17ae | 135 | /* number of bytes still to be read */ |
050c013a | 136 | #define STREAM_READABLE(S) ((S)->endp - (S)->getp) |
137 | ||
d62a17ae | 138 | #define STREAM_CONCAT_REMAIN(S1, S2, size) ((size) - (S1)->endp - (S2)->endp) |
8c71e481 | 139 | |
2d34fb80 QY |
140 | /* this macro is deprecated, but not slated for removal anytime soon */ |
141 | #define STREAM_DATA(S) ((S)->data) | |
142 | ||
d62a17ae | 143 | /* Stream prototypes. |
4b201d46 | 144 | * For stream_{put,get}S, the S suffix mean: |
145 | * | |
146 | * c: character (unsigned byte) | |
147 | * w: word (two bytes) | |
148 | * l: long (two words) | |
149 | * q: quad (four words) | |
150 | */ | |
d62a17ae | 151 | extern struct stream *stream_new(size_t); |
152 | extern void stream_free(struct stream *); | |
153 | extern struct stream *stream_copy(struct stream *, struct stream *src); | |
154 | extern struct stream *stream_dup(struct stream *); | |
43888669 | 155 | |
43888669 DS |
156 | extern size_t stream_resize_inplace(struct stream **sptr, size_t newsize); |
157 | ||
d62a17ae | 158 | extern size_t stream_get_getp(struct stream *); |
159 | extern size_t stream_get_endp(struct stream *); | |
160 | extern size_t stream_get_size(struct stream *); | |
d7c0a89a | 161 | extern uint8_t *stream_get_data(struct stream *); |
8cc4198f | 162 | |
8c71e481 PM |
163 | /** |
164 | * Create a new stream structure; copy offset bytes from s1 to the new | |
165 | * stream; copy s2 data to the new stream; copy rest of s1 data to the | |
166 | * new stream. | |
167 | */ | |
168 | extern struct stream *stream_dupcat(struct stream *s1, struct stream *s2, | |
169 | size_t offset); | |
170 | ||
d62a17ae | 171 | extern void stream_set_getp(struct stream *, size_t); |
172 | extern void stream_set_endp(struct stream *, size_t); | |
173 | extern void stream_forward_getp(struct stream *, size_t); | |
174 | extern void stream_forward_endp(struct stream *, size_t); | |
8cc4198f | 175 | |
176 | /* steam_put: NULL source zeroes out size_t bytes of stream */ | |
d62a17ae | 177 | extern void stream_put(struct stream *, const void *, size_t); |
d7c0a89a QY |
178 | extern int stream_putc(struct stream *, uint8_t); |
179 | extern int stream_putc_at(struct stream *, size_t, uint8_t); | |
180 | extern int stream_putw(struct stream *, uint16_t); | |
181 | extern int stream_putw_at(struct stream *, size_t, uint16_t); | |
182 | extern int stream_put3(struct stream *, uint32_t); | |
183 | extern int stream_put3_at(struct stream *, size_t, uint32_t); | |
184 | extern int stream_putl(struct stream *, uint32_t); | |
185 | extern int stream_putl_at(struct stream *, size_t, uint32_t); | |
d62a17ae | 186 | extern int stream_putq(struct stream *, uint64_t); |
187 | extern int stream_putq_at(struct stream *, size_t, uint64_t); | |
d7c0a89a | 188 | extern int stream_put_ipv4(struct stream *, uint32_t); |
d3d77ec4 MS |
189 | extern int stream_put_in_addr(struct stream *s, const struct in_addr *addr); |
190 | extern int stream_put_in_addr_at(struct stream *s, size_t putp, | |
191 | const struct in_addr *addr); | |
192 | extern int stream_put_in6_addr_at(struct stream *s, size_t putp, | |
193 | const struct in6_addr *addr); | |
194 | extern int stream_put_prefix_addpath(struct stream *s, | |
195 | const struct prefix *p, | |
d62a17ae | 196 | int addpath_encode, |
d7c0a89a | 197 | uint32_t addpath_tx_id); |
d3d77ec4 | 198 | extern int stream_put_prefix(struct stream *s, const struct prefix *p); |
5f040085 | 199 | extern int stream_put_labeled_prefix(struct stream *, const struct prefix *, |
ec15e1b5 QY |
200 | mpls_label_t *, int addpath_encode, |
201 | uint32_t addpath_tx_id); | |
d62a17ae | 202 | extern void stream_get(void *, struct stream *, size_t); |
051cc28c | 203 | extern bool stream_get2(void *data, struct stream *s, size_t size); |
d62a17ae | 204 | extern void stream_get_from(void *, struct stream *, size_t, size_t); |
d7c0a89a QY |
205 | extern uint8_t stream_getc(struct stream *); |
206 | extern bool stream_getc2(struct stream *s, uint8_t *byte); | |
207 | extern uint8_t stream_getc_from(struct stream *, size_t); | |
208 | extern uint16_t stream_getw(struct stream *); | |
051cc28c | 209 | extern bool stream_getw2(struct stream *s, uint16_t *word); |
d7c0a89a QY |
210 | extern uint16_t stream_getw_from(struct stream *, size_t); |
211 | extern uint32_t stream_get3(struct stream *); | |
212 | extern uint32_t stream_get3_from(struct stream *, size_t); | |
213 | extern uint32_t stream_getl(struct stream *); | |
051cc28c | 214 | extern bool stream_getl2(struct stream *s, uint32_t *l); |
d7c0a89a | 215 | extern uint32_t stream_getl_from(struct stream *, size_t); |
d62a17ae | 216 | extern uint64_t stream_getq(struct stream *); |
217 | extern uint64_t stream_getq_from(struct stream *, size_t); | |
c2b5a4e5 | 218 | bool stream_getq2(struct stream *s, uint64_t *q); |
d7c0a89a | 219 | extern uint32_t stream_get_ipv4(struct stream *); |
718e3744 | 220 | |
16f1b9ee | 221 | /* IEEE-754 floats */ |
d62a17ae | 222 | extern float stream_getf(struct stream *); |
223 | extern double stream_getd(struct stream *); | |
224 | extern int stream_putf(struct stream *, float); | |
225 | extern int stream_putd(struct stream *, double); | |
16f1b9ee | 226 | |
718e3744 | 227 | #undef stream_read |
228 | #undef stream_write | |
262feb1a | 229 | |
d62a17ae | 230 | /* Deprecated: assumes blocking I/O. Will be removed. |
262feb1a | 231 | Use stream_read_try instead. */ |
d62a17ae | 232 | extern int stream_read(struct stream *, int, size_t); |
262feb1a | 233 | |
262feb1a | 234 | /* Read up to size bytes into the stream. |
235 | Return code: | |
236 | >0: number of bytes read | |
237 | 0: end-of-file | |
238 | -1: fatal error | |
239 | -2: transient error, should retry later (i.e. EAGAIN or EINTR) | |
240 | This is suitable for use with non-blocking file descriptors. | |
241 | */ | |
242 | extern ssize_t stream_read_try(struct stream *s, int fd, size_t size); | |
243 | ||
d62a17ae | 244 | extern ssize_t stream_recvmsg(struct stream *s, int fd, struct msghdr *, |
245 | int flags, size_t size); | |
246 | extern ssize_t stream_recvfrom(struct stream *s, int fd, size_t len, int flags, | |
247 | struct sockaddr *from, socklen_t *fromlen); | |
248 | extern size_t stream_write(struct stream *, const void *, size_t); | |
718e3744 | 249 | |
8cc4198f | 250 | /* reset the stream. See Note above */ |
d62a17ae | 251 | extern void stream_reset(struct stream *); |
252 | extern int stream_flush(struct stream *, int); | |
253 | extern int stream_empty(struct stream *); /* is the stream empty? */ | |
050c013a | 254 | |
255 | /* deprecated */ | |
d7c0a89a | 256 | extern uint8_t *stream_pnt(struct stream *); |
718e3744 | 257 | |
363e24c6 QY |
258 | /* |
259 | * Operations on struct stream_fifo. | |
260 | * | |
261 | * Each function has a safe variant, which ensures that the operation performed | |
262 | * is atomic with respect to the operations performed by all other safe | |
263 | * variants. In other words, the safe variants lock the stream_fifo's mutex | |
264 | * before performing their action. These are provided for convenience when | |
265 | * using stream_fifo in a multithreaded context, to alleviate the need for the | |
266 | * caller to implement their own synchronization around the stream_fifo. | |
267 | * | |
268 | * The following functions do not have safe variants. The caller must ensure | |
269 | * that these operations are performed safely in a multithreaded context: | |
270 | * - stream_fifo_new | |
271 | * - stream_fifo_free | |
272 | */ | |
273 | ||
274 | /* | |
275 | * Create a new stream_fifo. | |
276 | * | |
277 | * Returns: | |
278 | * newly created stream_fifo | |
279 | */ | |
d62a17ae | 280 | extern struct stream_fifo *stream_fifo_new(void); |
363e24c6 QY |
281 | |
282 | /* | |
283 | * Push a stream onto a stream_fifo. | |
284 | * | |
285 | * fifo | |
286 | * the stream_fifo to push onto | |
287 | * | |
288 | * s | |
289 | * the stream to push onto the stream_fifo | |
290 | */ | |
d62a17ae | 291 | extern void stream_fifo_push(struct stream_fifo *fifo, struct stream *s); |
363e24c6 QY |
292 | extern void stream_fifo_push_safe(struct stream_fifo *fifo, struct stream *s); |
293 | ||
294 | /* | |
295 | * Pop a stream off a stream_fifo. | |
296 | * | |
297 | * fifo | |
298 | * the stream_fifo to pop from | |
299 | * | |
300 | * Returns: | |
301 | * the next stream in the stream_fifo | |
302 | */ | |
d62a17ae | 303 | extern struct stream *stream_fifo_pop(struct stream_fifo *fifo); |
363e24c6 QY |
304 | extern struct stream *stream_fifo_pop_safe(struct stream_fifo *fifo); |
305 | ||
306 | /* | |
307 | * Retrieve the next stream from a stream_fifo without popping it. | |
308 | * | |
309 | * fifo | |
310 | * the stream_fifo to operate on | |
311 | * | |
312 | * Returns: | |
313 | * the next stream that would be returned from stream_fifo_pop | |
314 | */ | |
d62a17ae | 315 | extern struct stream *stream_fifo_head(struct stream_fifo *fifo); |
363e24c6 QY |
316 | extern struct stream *stream_fifo_head_safe(struct stream_fifo *fifo); |
317 | ||
318 | /* | |
319 | * Remove all streams from a stream_fifo. | |
320 | * | |
321 | * fifo | |
322 | * the stream_fifo to clean | |
323 | */ | |
d62a17ae | 324 | extern void stream_fifo_clean(struct stream_fifo *fifo); |
363e24c6 QY |
325 | extern void stream_fifo_clean_safe(struct stream_fifo *fifo); |
326 | ||
327 | /* | |
328 | * Retrieve number of streams on a stream_fifo. | |
329 | * | |
330 | * fifo | |
331 | * the stream_fifo to retrieve the count for | |
332 | * | |
333 | * Returns: | |
334 | * the number of streams on the stream_fifo | |
335 | */ | |
336 | extern size_t stream_fifo_count_safe(struct stream_fifo *fifo); | |
337 | ||
338 | /* | |
339 | * Free a stream_fifo. | |
340 | * | |
341 | * Calls stream_fifo_clean, then deinitializes the stream_fifo and frees it. | |
342 | * | |
343 | * fifo | |
344 | * the stream_fifo to free | |
345 | */ | |
d62a17ae | 346 | extern void stream_fifo_free(struct stream_fifo *fifo); |
718e3744 | 347 | |
937652c6 DL |
348 | /* This is here because "<< 24" is particularly problematic in C. |
349 | * This is because the left operand of << is integer-promoted, which means | |
350 | * an uint8_t gets converted into a *signed* int. Shifting into the sign | |
351 | * bit of a signed int is theoretically undefined behaviour, so - the left | |
352 | * operand needs to be cast to unsigned. | |
353 | * | |
354 | * This is not a problem for 16- or 8-bit values (they don't reach the sign | |
355 | * bit), for 64-bit values (you need to cast them anyway), and neither for | |
356 | * encoding (because it's downcasted.) | |
357 | */ | |
1be1693e | 358 | static inline const uint8_t *ptr_get_be32(const uint8_t *ptr, uint32_t *out) |
937652c6 DL |
359 | { |
360 | uint32_t tmp; | |
1be1693e | 361 | |
937652c6 DL |
362 | memcpy(&tmp, ptr, sizeof(tmp)); |
363 | *out = ntohl(tmp); | |
364 | return ptr + 4; | |
365 | } | |
366 | ||
051cc28c DS |
367 | /* |
368 | * so Normal stream_getX functions assert. Which is anathema | |
369 | * to keeping a daemon up and running when something goes south | |
370 | * Provide a stream_getX2 functions that do not assert. | |
371 | * In addition provide these macro's that upon failure | |
372 | * goto stream_failure. This is modeled upon some NL_XX | |
373 | * macros in the linux kernel. | |
374 | * | |
375 | * This change allows for proper memory freeing | |
376 | * after we've detected an error. | |
377 | * | |
378 | * In the future we will be removing the assert in | |
379 | * the stream functions but we need a transition | |
380 | * plan. | |
381 | */ | |
996c9314 LB |
382 | #define STREAM_GETC(S, P) \ |
383 | do { \ | |
384 | uint8_t _pval; \ | |
385 | if (!stream_getc2((S), &_pval)) \ | |
386 | goto stream_failure; \ | |
387 | (P) = _pval; \ | |
051cc28c DS |
388 | } while (0) |
389 | ||
996c9314 LB |
390 | #define STREAM_GETW(S, P) \ |
391 | do { \ | |
392 | uint16_t _pval; \ | |
393 | if (!stream_getw2((S), &_pval)) \ | |
394 | goto stream_failure; \ | |
395 | (P) = _pval; \ | |
051cc28c DS |
396 | } while (0) |
397 | ||
996c9314 LB |
398 | #define STREAM_GETL(S, P) \ |
399 | do { \ | |
400 | uint32_t _pval; \ | |
401 | if (!stream_getl2((S), &_pval)) \ | |
402 | goto stream_failure; \ | |
403 | (P) = _pval; \ | |
051cc28c DS |
404 | } while (0) |
405 | ||
c2b5a4e5 QY |
406 | #define STREAM_GETF(S, P) \ |
407 | do { \ | |
408 | union { \ | |
409 | float r; \ | |
410 | uint32_t d; \ | |
411 | } _pval; \ | |
412 | if (stream_getl2((S), &_pval.d)) \ | |
413 | goto stream_failure; \ | |
414 | (P) = _pval.r; \ | |
415 | } while (0) | |
416 | ||
417 | #define STREAM_GETQ(S, P) \ | |
418 | do { \ | |
419 | uint64_t _pval; \ | |
420 | if (!stream_getq2((S), &_pval)) \ | |
421 | goto stream_failure; \ | |
422 | (P) = _pval; \ | |
423 | } while (0) | |
424 | ||
996c9314 LB |
425 | #define STREAM_GET(P, STR, SIZE) \ |
426 | do { \ | |
427 | if (!stream_get2((P), (STR), (SIZE))) \ | |
428 | goto stream_failure; \ | |
051cc28c DS |
429 | } while (0) |
430 | ||
5e244469 RW |
431 | #ifdef __cplusplus |
432 | } | |
433 | #endif | |
434 | ||
718e3744 | 435 | #endif /* _ZEBRA_STREAM_H */ |