1 /*
2 * include/common/htx.h
3 * This file defines everything related to the internal HTTP messages.
4 *
5 * Copyright (C) 2018 HAProxy Technologies, Christopher Faulet <cfaulet@haproxy.com>
6 *
7 * This library is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation, version 2.1
10 * exclusively.
11 *
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with this library; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22 #ifndef _COMMON_HTX_H
23 #define _COMMON_HTX_H
24
25 #include <stdio.h>
26 #include <common/buf.h>
27 #include <common/config.h>
28 #include <common/ist.h>
29 #include <common/http.h>
30 #include <common/http-hdr.h>
31 #include <common/standard.h>
32
33 /*
34 * The internal representation of an HTTP message, called HTX, is a structure
35 * with useful information on the message followed by a contiguous array
36 * containing parts of the message, called blocks. A block is composed of
37 * metadata (htx_blk) and the associated payload. Blocks' metadata are stored
38 * starting from the end of the array while their payload are stored at the
39 * beginning. Blocks' metadata are often simply called blocks. it is a misuse of
40 * language that's simplify explainations.
41 *
42 *
43 * +-----+---------------+------------------------------+--------------+
44 * | HTX | PAYLOADS ==> | | <== HTX_BLKs |
45 * +-----+---------------+------------------------------+--------------+
46 * ^
47 * blocks[] (the beginning of the bocks array)
48 *
49 *
50 * The blocks part remains linear and sorted. You may think about it as an array
51 * with negative indexes. But, instead of using negative indexes, we use
52 * positive positions to identify a block. This position is then converted to a
53 * address relatively to the beginning of the blocks array.
54 *
55 *
56 * .....--+------------------------------+-----+-----+
57 * | ... | BLK | BLK |
58 * .....--+------------------------------+-----+-----+
59 * ^ ^
60 * Addr of the block Addr of the block
61 * at the position 1 at the position 0
62 *
63 *
64 * The payloads part is a raw space that may wrap. You never access to a block's
65 * payload directly. Instead you get a block to retrieve the address of its
66 * payload. When no more space left between blocks and payloads parts, the free
67 * space at the beginning, if any, is used.
68 *
69 *
70 * +----------- WRAPPING ------------------------+
71 * | |
72 * V |
73 * +-----+-------------+---------------+---------------++--------------+
74 * | HTX | PAYLOAD ==> | | PAYLOADS ==X || X== HTX_BLKs |
75 * +-----+-------------+---------------+---------------++--------------+
76 *
77 *
78 * The blocks part, on its side, never wrap. If we have no space to allocate a
79 * new block and if there is a hole at the beginning of the blocks part (so at
80 * the end of the blocks array), we move back all blocks.x
81 *
82 *
83 * ...+--------------+----------+ blocks ...+----------+--------------+
84 * | X== HTX_BLKS | | defrag | | <== HTX_BLKS |
85 * ...+--------------+----------+ =====> ...+----------+--------------+
86 *
87 *
88 * At the end, if payload wrapping or blocks defragmenation is not enough, some
89 * free space may be get back with a full defragmenation. This way, the holes in
90 * the middle are not reusable but count in the available free space. The only
91 * way to reuse this lost space is to fully defragmenate the HTX message.
92 *
93 * - * -
94 *
95 * An HTX block is as well a header as a body part or a trailer. For all these
96 * types of block, a payload is attached to the block. It can also be a mark,
97 * like the end-of-headers or end-of-message. For these blocks, there is no
98 * payload but it count for a byte. It is important to not skip it when data are
99 * forwarded. Metadata of an HTX block are composed of 2 fields :
100 *
101 * - .info : It a 32 bits field containing the block's type on 4 bits
102 * followed by the payload length. See below for details.
103 *
104 * - .addr : The payload's address, if any, relatively to the beginning the
105 * array used to store the HTX message itself.
106 *
107 * htx_blk.info representation :
108 *
109 * 0b 0000 0000 0000 0000 0000 0000 0000 0000
110 * ---- ------------------------ ---------
111 * type value (1 MB max) name length (header/trailer)
112 * ----------------------------------
113 * data length (256 MB max)
114 * (body, method, path, version, status, reason)
115 *
116 * types :
117 * - 0000 = request start-line
118 * - 0001 = response start-line
119 * - 0010 = header
120 * - 0011 = pseudo-header ou "special" header
121 * - 0100 = end-of-headers
122 * - 0101 = data
123 * - 0110 = trailer
124 * - 0111 = end-of-trailers
125 * - 1000 = end-of-message
126 * ...
127 * - 1111 = unused
128 *
129 */
130
131 /* HTX start-line flags */
132 #define HTX_SL_F_NONE 0x00000000
133 #define HTX_SL_F_IS_RESP 0x00000001 /* It is the response start-line (unset means the request one) */
134 #define HTX_SL_F_XFER_LEN 0x00000002 /* The message xfer size can be dertermined */
135 #define HTX_SL_F_XFER_ENC 0x00000004 /* The transfer-encoding header was found in message */
136 #define HTX_SL_F_CLEN 0x00000008 /* The content-length header was found in message */
137 #define HTX_SL_F_CHNK 0x00000010 /* The message payload is chunked */
138 #define HTX_SL_F_VER_11 0x00000020 /* The message indicates version 1.1 or above */
139 #define HTX_SL_F_BODYLESS 0x00000040 /* The message has no body (content-length = 0) */
140 #define HTX_SL_F_HAS_SCHM 0x00000080 /* The scheme is explicitly specified */
141 #define HTX_SL_F_SCHM_HTTP 0x00000100 /* The scheme HTTP should be used */
142 #define HTX_SL_F_SCHM_HTTPS 0x00000200 /* The scheme HTTPS should be used */
143 #define HTX_SL_F_HAS_AUTHORITY 0x00000400 /* The request authority is explicitly specified */
144 #define HTX_SL_F_NORMALIZED_URI 0x00000800 /* The received URI is normalized (an implicit absolute-uri form) */
145
146
147 /* HTX flags */
148 #define HTX_FL_NONE 0x00000000
149 #define HTX_FL_PARSING_ERROR 0x00000001 /* Set when a parsing error occurred */
150 #define HTX_FL_PROCESSING_ERROR 0x00000002 /* Set when a processing error occurred */
151 #define HTX_FL_UPGRADE 0x00000004 /* Set when an upgrade is in progress */
152 #define HTX_FL_PROXY_RESP 0x00000008 /* Set when the response was generated by HAProxy */
153
154
155 /* HTX block's type (max 15). */
156 enum htx_blk_type {
157 HTX_BLK_REQ_SL = 0, /* Request start-line */
158 HTX_BLK_RES_SL = 1, /* Response start-line */
159 HTX_BLK_HDR = 2, /* header name/value block */
160 HTX_BLK_EOH = 3, /* end-of-headers block */
161 HTX_BLK_DATA = 4, /* data block */
162 HTX_BLK_TLR = 5, /* trailer name/value block */
163 HTX_BLK_EOT = 6, /* end-of-trailers block */
164 HTX_BLK_EOM = 7, /* end-of-message block */
165 /* 8 .. 14 unused */
166 HTX_BLK_UNUSED = 15, /* unused/removed block */
167 };
168
169 /* One HTX block descriptor */
170 struct htx_blk {
171 uint32_t addr; /* relative storage address of the block's payload */
172 uint32_t info; /* information about the block (type, length) */
173 };
174
175 /* Composite return value used by some HTX functions */
176 struct htx_ret {
177 int32_t ret; /* A numerical value */
178 struct htx_blk *blk; /* An HTX block */
179 };
180
181 /* HTX start-line */
182 struct htx_sl {
183 unsigned int flags; /* HTX_SL_F_* */
184 union {
185 struct {
186 enum http_meth_t meth; /* method */
187 } req;
188 struct {
189 uint16_t status; /* status code */
190 } res;
191 } info;
192
193 /* XXX 2 bytes unused */
194
195 int32_t hdrs_bytes; /* Bytes held by all headers, as seen by the mux
196 * during parsing, from this start-line to the
197 * corresponding EOH. -1 if unknown */
198
199 unsigned int len[3]; /* length of differnt parts of the start-line */
200 char l[0];
201 };
202
203 /* Internal representation of an HTTP message */
204 struct htx {
205 uint32_t size; /* the array size, in bytes, used to store the HTTP message itself */
206 uint32_t data; /* the data size, in bytes. To known to total size used by all allocated
207 * blocks (blocks and their contents), you need to add size used by blocks,
208 * i.e. [ used * sizeof(struct htx_blk *) ] */
209
210 int32_t tail; /* newest inserted block. -1 if the HTX message is empty */
211 int32_t head; /* oldest inserted block. -1 if the HTX message is empty */
212 int32_t first; /* position of the first block to (re)start the analyse. -1 if unset. */
213
214 uint32_t tail_addr; /* start address of the free space in front of the the blocks table */
215 uint32_t head_addr; /* start address of the free space at the beginning */
216 uint32_t end_addr; /* end address of the free space at the beginning */
217
218 uint64_t extra; /* known bytes amount remaining to receive */
219 uint32_t flags; /* HTX_FL_* */
220
221 /* XXX 4 bytes unused */
222
223 /* Blocks representing the HTTP message itself */
224 char blocks[0] __attribute__((aligned(8)));
225 };
226
227
228 extern struct htx htx_empty;
229
230 struct htx_blk *htx_defrag(struct htx *htx, struct htx_blk *blk);
231 struct htx_blk *htx_add_blk(struct htx *htx, enum htx_blk_type type, uint32_t blksz);
232 struct htx_blk *htx_remove_blk(struct htx *htx, struct htx_blk *blk);
233 struct htx_ret htx_find_offset(struct htx *htx, uint32_t offset);
234 void htx_truncate(struct htx *htx, uint32_t offset);
235 struct htx_ret htx_drain(struct htx *htx, uint32_t max);
236
237 struct htx_blk *htx_replace_blk_value(struct htx *htx, struct htx_blk *blk,
238 const struct ist old, const struct ist new);
239 struct htx_ret htx_xfer_blks(struct htx *dst, struct htx *src, uint32_t count,
240 enum htx_blk_type mark);
241
242 struct htx_sl *htx_add_stline(struct htx *htx, enum htx_blk_type type, unsigned int flags,
243 const struct ist p1, const struct ist p2, const struct ist p3);
244 struct htx_sl *htx_replace_stline(struct htx *htx, struct htx_blk *blk, const struct ist p1,
245 const struct ist p2, const struct ist p3);
246
247 struct htx_blk *htx_replace_header(struct htx *htx, struct htx_blk *blk,
248 const struct ist name, const struct ist value);
249
250 struct htx_blk *htx_add_header(struct htx *htx, const struct ist name, const struct ist value);
251 struct htx_blk *htx_add_trailer(struct htx *htx, const struct ist name, const struct ist value);
252 struct htx_blk *htx_add_all_headers(struct htx *htx, const struct http_hdr *hdrs);
253 struct htx_blk *htx_add_all_trailers(struct htx *htx, const struct http_hdr *hdrs);
254 struct htx_blk *htx_add_endof(struct htx *htx, enum htx_blk_type type);
255 struct htx_blk *htx_add_data_atonce(struct htx *htx, struct ist data);
256 size_t htx_add_data(struct htx *htx, const struct ist data);
257 struct htx_blk *htx_add_last_data(struct htx *htx, struct ist data);
258 void htx_move_blk_before(struct htx *htx, struct htx_blk **blk, struct htx_blk **ref);
259 int htx_append_msg(struct htx *dst, const struct htx *src);
260
261 /* Functions and macros to get parts of the start-line or legnth of these
262 * parts. Request and response start-lines are both composed of 3 parts.
263 */
264 #define HTX_SL_LEN(sl) ((sl)->len[0] + (sl)->len[1] + (sl)->len[2])
265
266 #define HTX_SL_P1_LEN(sl) ((sl)->len[0])
267 #define HTX_SL_P2_LEN(sl) ((sl)->len[1])
268 #define HTX_SL_P3_LEN(sl) ((sl)->len[2])
269 #define HTX_SL_P1_PTR(sl) ((sl)->l)
270 #define HTX_SL_P2_PTR(sl) (HTX_SL_P1_PTR(sl) + HTX_SL_P1_LEN(sl))
271 #define HTX_SL_P3_PTR(sl) (HTX_SL_P2_PTR(sl) + HTX_SL_P2_LEN(sl))
272
273 #define HTX_SL_REQ_MLEN(sl) HTX_SL_P1_LEN(sl)
274 #define HTX_SL_REQ_ULEN(sl) HTX_SL_P2_LEN(sl)
275 #define HTX_SL_REQ_VLEN(sl) HTX_SL_P3_LEN(sl)
276 #define HTX_SL_REQ_MPTR(sl) HTX_SL_P1_PTR(sl)
277 #define HTX_SL_REQ_UPTR(sl) HTX_SL_P2_PTR(sl)
278 #define HTX_SL_REQ_VPTR(sl) HTX_SL_P3_PTR(sl)
279
280 #define HTX_SL_RES_VLEN(sl) HTX_SL_P1_LEN(sl)
281 #define HTX_SL_RES_CLEN(sl) HTX_SL_P2_LEN(sl)
282 #define HTX_SL_RES_RLEN(sl) HTX_SL_P3_LEN(sl)
283 #define HTX_SL_RES_VPTR(sl) HTX_SL_P1_PTR(sl)
284 #define HTX_SL_RES_CPTR(sl) HTX_SL_P2_PTR(sl)
285 #define HTX_SL_RES_RPTR(sl) HTX_SL_P3_PTR(sl)
286
htx_sl_p1(const struct htx_sl * sl)287 static inline struct ist htx_sl_p1(const struct htx_sl *sl)
288 {
289 return ist2(HTX_SL_P1_PTR(sl), HTX_SL_P1_LEN(sl));
290 }
291
htx_sl_p2(const struct htx_sl * sl)292 static inline struct ist htx_sl_p2(const struct htx_sl *sl)
293 {
294 return ist2(HTX_SL_P2_PTR(sl), HTX_SL_P2_LEN(sl));
295 }
296
htx_sl_p3(const struct htx_sl * sl)297 static inline struct ist htx_sl_p3(const struct htx_sl *sl)
298 {
299 return ist2(HTX_SL_P3_PTR(sl), HTX_SL_P3_LEN(sl));
300 }
301
htx_sl_req_meth(const struct htx_sl * sl)302 static inline struct ist htx_sl_req_meth(const struct htx_sl *sl)
303 {
304 return htx_sl_p1(sl);
305 }
306
htx_sl_req_uri(const struct htx_sl * sl)307 static inline struct ist htx_sl_req_uri(const struct htx_sl *sl)
308 {
309 return htx_sl_p2(sl);
310 }
311
htx_sl_req_vsn(const struct htx_sl * sl)312 static inline struct ist htx_sl_req_vsn(const struct htx_sl *sl)
313 {
314 return htx_sl_p3(sl);
315 }
316
317
htx_sl_res_vsn(const struct htx_sl * sl)318 static inline struct ist htx_sl_res_vsn(const struct htx_sl *sl)
319 {
320 return htx_sl_p1(sl);
321 }
322
htx_sl_res_code(const struct htx_sl * sl)323 static inline struct ist htx_sl_res_code(const struct htx_sl *sl)
324 {
325 return htx_sl_p2(sl);
326 }
327
htx_sl_res_reason(const struct htx_sl * sl)328 static inline struct ist htx_sl_res_reason(const struct htx_sl *sl)
329 {
330 return htx_sl_p3(sl);
331 }
332
333 /* Converts a position to the corresponding relative address */
htx_pos_to_addr(const struct htx * htx,uint32_t pos)334 static inline uint32_t htx_pos_to_addr(const struct htx *htx, uint32_t pos)
335 {
336 return htx->size - (pos + 1) * sizeof(struct htx_blk);
337 }
338
339 /* Returns the position of the block <blk>. It is the caller responsibility to
340 * be sure <blk> is part of <htx>. */
htx_get_blk_pos(const struct htx * htx,const struct htx_blk * blk)341 static inline uint32_t htx_get_blk_pos(const struct htx *htx, const struct htx_blk *blk)
342 {
343 return ((htx->blocks + htx->size - (char *)blk) / sizeof(struct htx_blk) - 1);
344 }
345
346 /* Returns the block at the position <pos>. It is the caller responsibility to
347 * be sure the block at the position <pos> exists. */
htx_get_blk(const struct htx * htx,uint32_t pos)348 static inline struct htx_blk *htx_get_blk(const struct htx *htx, uint32_t pos)
349 {
350 return (struct htx_blk *)(htx->blocks + htx_pos_to_addr(htx, pos));
351 }
352
353 /* Returns the type of the block <blk> */
htx_get_blk_type(const struct htx_blk * blk)354 static inline enum htx_blk_type htx_get_blk_type(const struct htx_blk *blk)
355 {
356 return (blk->info >> 28);
357 }
358
359 /* Returns the size of the block <blk>, depending of its type */
htx_get_blksz(const struct htx_blk * blk)360 static inline uint32_t htx_get_blksz(const struct htx_blk *blk)
361 {
362 enum htx_blk_type type = htx_get_blk_type(blk);
363
364 switch (type) {
365 case HTX_BLK_HDR:
366 case HTX_BLK_TLR:
367 /* name.length + value.length */
368 return ((blk->info & 0xff) + ((blk->info >> 8) & 0xfffff));
369 default:
370 /* value.length */
371 return (blk->info & 0xfffffff);
372 }
373 }
374
375 /* Returns the position of the oldest entry (head). It returns a signed 32-bits
376 * integer, -1 means the HTX message is empty.
377 */
htx_get_head(const struct htx * htx)378 static inline int32_t htx_get_head(const struct htx *htx)
379 {
380 return htx->head;
381 }
382
383 /* Returns the oldest HTX block (head) if the HTX message is not
384 * empty. Otherwise it returns NULL.
385 */
htx_get_head_blk(const struct htx * htx)386 static inline struct htx_blk *htx_get_head_blk(const struct htx *htx)
387 {
388 int32_t head = htx_get_head(htx);
389
390 return ((head == -1) ? NULL : htx_get_blk(htx, head));
391 }
392
393 /* Returns the type of the oldest HTX block (head) if the HTX message is not
394 * empty. Otherwise it returns HTX_BLK_UNUSED.
395 */
htx_get_head_type(const struct htx * htx)396 static inline enum htx_blk_type htx_get_head_type(const struct htx *htx)
397 {
398 struct htx_blk *blk = htx_get_head_blk(htx);
399
400 return (blk ? htx_get_blk_type(blk) : HTX_BLK_UNUSED);
401 }
402
403 /* Returns the position of the newest entry (tail). It returns a signed 32-bits
404 * integer, -1 means the HTX message is empty.
405 */
htx_get_tail(const struct htx * htx)406 static inline int32_t htx_get_tail(const struct htx *htx)
407 {
408 return htx->tail;
409 }
410
411 /* Returns the newest HTX block (tail) if the HTX message is not
412 * empty. Otherwise it returns NULL.
413 */
htx_get_tail_blk(const struct htx * htx)414 static inline struct htx_blk *htx_get_tail_blk(const struct htx *htx)
415 {
416 int32_t tail = htx_get_tail(htx);
417
418 return ((tail == -1) ? NULL : htx_get_blk(htx, tail));
419 }
420
421 /* Returns the type of the newest HTX block (tail) if the HTX message is not
422 * empty. Otherwise it returns HTX_BLK_UNUSED.
423 */
htx_get_tail_type(const struct htx * htx)424 static inline enum htx_blk_type htx_get_tail_type(const struct htx *htx)
425 {
426 struct htx_blk *blk = htx_get_tail_blk(htx);
427
428 return (blk ? htx_get_blk_type(blk) : HTX_BLK_UNUSED);
429 }
430
431 /* Returns the position of the first block in the HTX message <htx>. -1 means
432 * the first block is unset or the HTS is empty.
433 */
htx_get_first(const struct htx * htx)434 static inline int32_t htx_get_first(const struct htx *htx)
435 {
436 return htx->first;
437 }
438
439 /* Returns the first HTX block in the HTX message <htx>. If unset or if <htx> is
440 * empty, NULL returned.
441 */
htx_get_first_blk(const struct htx * htx)442 static inline struct htx_blk *htx_get_first_blk(const struct htx *htx)
443 {
444 int32_t pos;
445
446 pos = htx_get_first(htx);
447 return ((pos == -1) ? NULL : htx_get_blk(htx, pos));
448 }
449
450 /* Returns the type of the first block in the HTX message <htx>. If unset or if
451 * <htx> is empty, HTX_BLK_UNUSED is returned.
452 */
htx_get_first_type(const struct htx * htx)453 static inline enum htx_blk_type htx_get_first_type(const struct htx *htx)
454 {
455 struct htx_blk *blk = htx_get_first_blk(htx);
456
457 return (blk ? htx_get_blk_type(blk) : HTX_BLK_UNUSED);
458 }
459
460 /* Returns the position of block immediately before the one pointed by <pos>. If
461 * the message is empty or if <pos> is the position of the head, -1 returned.
462 */
htx_get_prev(const struct htx * htx,uint32_t pos)463 static inline int32_t htx_get_prev(const struct htx *htx, uint32_t pos)
464 {
465 if (htx->head == -1 || pos == htx->head)
466 return -1;
467 return (pos - 1);
468 }
469
470 /* Returns the HTX block before <blk> in the HTX message <htx>. If <blk> is the
471 * head, NULL returned.
472 */
htx_get_prev_blk(const struct htx * htx,const struct htx_blk * blk)473 static inline struct htx_blk *htx_get_prev_blk(const struct htx *htx,
474 const struct htx_blk *blk)
475 {
476 int32_t pos;
477
478 pos = htx_get_prev(htx, htx_get_blk_pos(htx, blk));
479 return ((pos == -1) ? NULL : htx_get_blk(htx, pos));
480 }
481
482 /* Returns the position of block immediately after the one pointed by <pos>. If
483 * the message is empty or if <pos> is the position of the tail, -1 returned.
484 */
htx_get_next(const struct htx * htx,uint32_t pos)485 static inline int32_t htx_get_next(const struct htx *htx, uint32_t pos)
486 {
487 if (htx->tail == -1 || pos == htx->tail)
488 return -1;
489 return (pos + 1);
490
491 }
492
493 /* Returns the HTX block after <blk> in the HTX message <htx>. If <blk> is the
494 * tail, NULL returned.
495 */
htx_get_next_blk(const struct htx * htx,const struct htx_blk * blk)496 static inline struct htx_blk *htx_get_next_blk(const struct htx *htx,
497 const struct htx_blk *blk)
498 {
499 int32_t pos;
500
501 pos = htx_get_next(htx, htx_get_blk_pos(htx, blk));
502 return ((pos == -1) ? NULL : htx_get_blk(htx, pos));
503 }
504
505 /* Changes the size of the value. It is the caller responsibility to change the
506 * value itself, make sure there is enough space and update allocated
507 * value. This function updates the HTX message accordingly.
508 */
htx_change_blk_value_len(struct htx * htx,struct htx_blk * blk,uint32_t newlen)509 static inline void htx_change_blk_value_len(struct htx *htx, struct htx_blk *blk, uint32_t newlen)
510 {
511 enum htx_blk_type type = htx_get_blk_type(blk);
512 uint32_t oldlen, sz;
513 int32_t delta;
514
515 sz = htx_get_blksz(blk);
516 switch (type) {
517 case HTX_BLK_HDR:
518 case HTX_BLK_TLR:
519 oldlen = (blk->info >> 8) & 0xfffff;
520 blk->info = (type << 28) + (newlen << 8) + (blk->info & 0xff);
521 break;
522 default:
523 oldlen = blk->info & 0xfffffff;
524 blk->info = (type << 28) + newlen;
525 break;
526 }
527
528 /* Update HTTP message */
529 delta = (newlen - oldlen);
530 htx->data += delta;
531 if (blk->addr+sz == htx->tail_addr)
532 htx->tail_addr += delta;
533 else if (blk->addr+sz == htx->head_addr)
534 htx->head_addr += delta;
535 }
536
537 /* Changes the size of the value. It is the caller responsibility to change the
538 * value itself, make sure there is enough space and update allocated
539 * value. Unlike the function htx_change_blk_value_len(), this one does not
540 * update the HTX message. So it should be used with caution.
541 */
htx_set_blk_value_len(struct htx_blk * blk,uint32_t vlen)542 static inline void htx_set_blk_value_len(struct htx_blk *blk, uint32_t vlen)
543 {
544 enum htx_blk_type type = htx_get_blk_type(blk);
545
546 switch (type) {
547 case HTX_BLK_HDR:
548 case HTX_BLK_TLR:
549 blk->info = (type << 28) + (vlen << 8) + (blk->info & 0xff);
550 break;
551 case HTX_BLK_REQ_SL:
552 case HTX_BLK_RES_SL:
553 case HTX_BLK_DATA:
554 blk->info = (type << 28) + vlen;
555 break;
556 default:
557 /* Unexpected case */
558 break;
559 }
560 }
561
562 /* Returns the data pointer of the block <blk> */
htx_get_blk_ptr(const struct htx * htx,const struct htx_blk * blk)563 static inline void *htx_get_blk_ptr(const struct htx *htx, const struct htx_blk *blk)
564 {
565 return ((void *)htx->blocks + blk->addr);
566 }
567
568 /* Returns the name of the block <blk>, only if it is a header or a
569 * trailer. Otherwise it returns an empty string.
570 */
htx_get_blk_name(const struct htx * htx,const struct htx_blk * blk)571 static inline struct ist htx_get_blk_name(const struct htx *htx, const struct htx_blk *blk)
572 {
573 enum htx_blk_type type = htx_get_blk_type(blk);
574 struct ist ret;
575
576 switch (type) {
577 case HTX_BLK_HDR:
578 case HTX_BLK_TLR:
579 ret.ptr = htx_get_blk_ptr(htx, blk);
580 ret.len = blk->info & 0xff;
581 break;
582
583 default:
584 return ist("");
585 }
586 return ret;
587 }
588
589
590 /* Returns the value of the block <blk>, depending on its type. If there is no
591 * value (for end-of blocks), an empty one is retruned.
592 */
htx_get_blk_value(const struct htx * htx,const struct htx_blk * blk)593 static inline struct ist htx_get_blk_value(const struct htx *htx, const struct htx_blk *blk)
594 {
595 enum htx_blk_type type = htx_get_blk_type(blk);
596 struct ist ret;
597
598 switch (type) {
599 case HTX_BLK_HDR:
600 case HTX_BLK_TLR:
601 ret.ptr = htx_get_blk_ptr(htx, blk) + (blk->info & 0xff);
602 ret.len = (blk->info >> 8) & 0xfffff;
603 break;
604
605 case HTX_BLK_REQ_SL:
606 case HTX_BLK_RES_SL:
607 case HTX_BLK_DATA:
608 ret.ptr = htx_get_blk_ptr(htx, blk);
609 ret.len = blk->info & 0xfffffff;
610 break;
611
612 default:
613 return ist("");
614 }
615 return ret;
616 }
617
618 /* Removes <n> bytes from the beginning of DATA block <blk>. The block's start
619 * address and its length are adjusted, and the htx's total data count is
620 * updated. This is used to mark that part of some data were transfered
621 * from a DATA block without removing this DATA block. No sanity check is
622 * performed, the caller is reponsible for doing this exclusively on DATA
623 * blocks, and never removing more than the block's size.
624 */
htx_cut_data_blk(struct htx * htx,struct htx_blk * blk,uint32_t n)625 static inline void htx_cut_data_blk(struct htx *htx, struct htx_blk *blk, uint32_t n)
626 {
627 if (blk->addr == htx->end_addr)
628 htx->end_addr += n;
629 blk->addr += n;
630 blk->info -= n;
631 htx->data -= n;
632 }
633
634 /* Returns the space used by metadata in <htx>. */
htx_meta_space(const struct htx * htx)635 static inline uint32_t htx_meta_space(const struct htx *htx)
636 {
637 if (htx->tail == -1)
638 return 0;
639
640 return ((htx->tail + 1 - htx->head) * sizeof(struct htx_blk));
641 }
642
643 /* Returns the space used (payload + metadata) in <htx> */
htx_used_space(const struct htx * htx)644 static inline uint32_t htx_used_space(const struct htx *htx)
645 {
646 return (htx->data + htx_meta_space(htx));
647 }
648
649 /* Returns the free space in <htx> */
htx_free_space(const struct htx * htx)650 static inline uint32_t htx_free_space(const struct htx *htx)
651 {
652 return (htx->size - htx_used_space(htx));
653 }
654
655 /* Returns the maximum size available to store some data in <htx> if a new block
656 * is reserved.
657 */
htx_free_data_space(const struct htx * htx)658 static inline uint32_t htx_free_data_space(const struct htx *htx)
659 {
660 uint32_t free = htx_free_space(htx);
661
662 if (free < sizeof(struct htx_blk))
663 return 0;
664 return (free - sizeof(struct htx_blk));
665 }
666
667 /* Returns the maximum size for a block, not exceeding <max> bytes. <max> may be
668 * set to -1 to have no limit.
669 */
htx_get_max_blksz(const struct htx * htx,int32_t max)670 static inline uint32_t htx_get_max_blksz(const struct htx *htx, int32_t max)
671 {
672 uint32_t free = htx_free_space(htx);
673
674 if (max != -1 && free > max)
675 free = max;
676 if (free < sizeof(struct htx_blk))
677 return 0;
678 return (free - sizeof(struct htx_blk));
679 }
680
681 /* Returns 1 if the message has less than 1/4 of its capacity free, otherwise 0 */
htx_almost_full(const struct htx * htx)682 static inline int htx_almost_full(const struct htx *htx)
683 {
684 if (!htx->size || htx_free_space(htx) < htx->size / 4)
685 return 1;
686 return 0;
687 }
688
689 /* Resets an HTX message */
htx_reset(struct htx * htx)690 static inline void htx_reset(struct htx *htx)
691 {
692 htx->tail = htx->head = htx->first = -1;
693 htx->data = 0;
694 htx->tail_addr = htx->head_addr = htx->end_addr = 0;
695 htx->extra = 0;
696 htx->flags = HTX_FL_NONE;
697 }
698
699 /* Returns the available room for raw data in buffer <buf> once HTX overhead is
700 * taken into account (one HTX header and two blocks). The purpose is to figure
701 * the optimal fill length to avoid copies.
702 */
buf_room_for_htx_data(const struct buffer * buf)703 static inline size_t buf_room_for_htx_data(const struct buffer *buf)
704 {
705 size_t room;
706
707 room = b_room(buf);
708 if (room <= sizeof(struct htx) + 2 * sizeof(struct htx_blk))
709 room = 0;
710 else
711 room -= sizeof(struct htx) + 2 * sizeof(struct htx_blk);
712
713 return room;
714 }
715
716
717 /* Returns an HTX message using the buffer <buf>. Unlike htx_from_buf(), this
718 * function does not update the buffer. So if the HTX message is updated, the
719 * caller must call htx_to_buf() to be sure to also update the underlying buffer
720 * accordingly. Note that it always returns a valid pointer, either to an
721 * initialized buffer or to the empty buffer. This function must always be
722 * called with a buffer containing an HTX message (or an empty buffer).
723 */
htxbuf(const struct buffer * buf)724 static inline struct htx *htxbuf(const struct buffer *buf)
725 {
726 struct htx *htx;
727
728 if (b_is_null(buf))
729 return &htx_empty;
730 htx = ((struct htx *)(buf->area));
731 if (!b_data(buf)) {
732 htx->size = buf->size - sizeof(*htx);
733 htx_reset(htx);
734 }
735 return htx;
736 }
737
738 /* Returns an HTX message using the buffer <buf>. <buf> is updated to appear as
739 * full. It should be used when you want to add something into the HTX message,
740 * so the call to htx_to_buf() may be skipped. But, it is the caller
741 * responsibility to call htx_to_buf() to reset <buf> if it is relevant. The
742 * returned pointer is always valid. This function must always be called with a
743 * buffer containing an HTX message (or an empty buffer).
744 *
745 * The caller can call htxbuf() function to avoid any update of the buffer.
746 */
htx_from_buf(struct buffer * buf)747 static inline struct htx *htx_from_buf(struct buffer *buf)
748 {
749 struct htx *htx = htxbuf(buf);
750
751 b_set_data(buf, b_size(buf));
752 return htx;
753 }
754
755 /* Update <buf> accordingly to the HTX message <htx> */
htx_to_buf(struct htx * htx,struct buffer * buf)756 static inline void htx_to_buf(struct htx *htx, struct buffer *buf)
757 {
758 if ((htx->head == -1) &&
759 !(htx->flags & (HTX_FL_PARSING_ERROR|HTX_FL_PROCESSING_ERROR|HTX_FL_UPGRADE))) {
760 htx_reset(htx);
761 b_set_data(buf, 0);
762 }
763 else
764 b_set_data(buf, b_size(buf));
765 }
766
767 /* Returns 1 if the message is empty, otherwise it returns 0. Note that it is
768 * illegal to call this with htx == NULL.
769 */
htx_is_empty(const struct htx * htx)770 static inline int htx_is_empty(const struct htx *htx)
771 {
772 return (htx->head == -1);
773 }
774
775 /* Returns 1 if the message is not empty, otherwise it returns 0. Note that it
776 * is illegal to call this with htx == NULL.
777 */
htx_is_not_empty(const struct htx * htx)778 static inline int htx_is_not_empty(const struct htx *htx)
779 {
780 return (htx->head != -1);
781 }
782
htx_skip_msg_payload(struct htx * htx)783 static inline void htx_skip_msg_payload(struct htx *htx)
784 {
785 struct htx_blk *blk = htx_get_first_blk(htx);
786
787 while (blk) {
788 enum htx_blk_type type = htx_get_blk_type(blk);
789
790 blk = ((type > HTX_BLK_EOH && type < HTX_BLK_EOM)
791 ? htx_remove_blk(htx, blk)
792 : htx_get_next_blk(htx, blk));
793 }
794 }
795
796 /* Returns the number of used blocks in the HTX message <htx>. Note that it is
797 * illegal to call this function with htx == NULL. Note also blocks of type
798 * HTX_BLK_UNUSED are part of used blocks.
799 */
htx_nbblks(const struct htx * htx)800 static inline int htx_nbblks(const struct htx *htx)
801 {
802 return ((htx->head != -1) ? (htx->tail + 1 - htx->head) : 0);
803 }
804 /* For debugging purpose */
htx_blk_type_str(enum htx_blk_type type)805 static inline const char *htx_blk_type_str(enum htx_blk_type type)
806 {
807 switch (type) {
808 case HTX_BLK_REQ_SL: return "HTX_BLK_REQ_SL";
809 case HTX_BLK_RES_SL: return "HTX_BLK_RES_SL";
810 case HTX_BLK_HDR: return "HTX_BLK_HDR";
811 case HTX_BLK_EOH: return "HTX_BLK_EOH";
812 case HTX_BLK_DATA: return "HTX_BLK_DATA";
813 case HTX_BLK_TLR: return "HTX_BLK_TLR";
814 case HTX_BLK_EOT: return "HTX_BLK_EOT";
815 case HTX_BLK_EOM: return "HTX_BLK_EOM";
816 case HTX_BLK_UNUSED: return "HTX_BLK_UNUSED";
817 default: return "HTX_BLK_???";
818 };
819 }
820
821 /* For debugging purpose */
htx_dump(struct buffer * chunk,const struct htx * htx,int full)822 static inline void htx_dump(struct buffer *chunk, const struct htx *htx, int full)
823 {
824 int32_t pos;
825
826 chunk_appendf(chunk, " htx=%p(size=%u,data=%u,used=%u,wrap=%s,flags=0x%08x,extra=%llu,"
827 "first=%d,head=%d,tail=%d,tail_addr=%d,head_addr=%d,end_addr=%d)",
828 htx, htx->size, htx->data, htx_nbblks(htx), (!htx->head_addr) ? "NO" : "YES",
829 htx->flags, (unsigned long long)htx->extra, htx->first, htx->head, htx->tail,
830 htx->tail_addr, htx->head_addr, htx->end_addr);
831
832 if (!full || !htx_nbblks(htx))
833 return;
834 chunk_memcat(chunk, "\n", 1);
835
836 for (pos = htx_get_head(htx); pos != -1; pos = htx_get_next(htx, pos)) {
837 struct htx_sl *sl;
838 struct htx_blk *blk = htx_get_blk(htx, pos);
839 enum htx_blk_type type = htx_get_blk_type(blk);
840 uint32_t sz = htx_get_blksz(blk);
841 struct ist n, v;
842
843 n = htx_get_blk_name(htx, blk);
844 v = htx_get_blk_value(htx, blk);
845
846 if (type == HTX_BLK_REQ_SL || type == HTX_BLK_RES_SL) {
847 sl = htx_get_blk_ptr(htx, blk);
848 chunk_appendf(chunk, "\t\t[%u] type=%-17s - size=%-6u - addr=%-6u\t%.*s %.*s %.*s\n",
849 pos, htx_blk_type_str(type), sz, blk->addr,
850 HTX_SL_P1_LEN(sl), HTX_SL_P1_PTR(sl),
851 HTX_SL_P2_LEN(sl), HTX_SL_P2_PTR(sl),
852 HTX_SL_P3_LEN(sl), HTX_SL_P3_PTR(sl));
853 }
854 else if (type == HTX_BLK_HDR || type == HTX_BLK_TLR)
855 chunk_appendf(chunk, "\t\t[%u] type=%-17s - size=%-6u - addr=%-6u\t%.*s: %.*s\n",
856 pos, htx_blk_type_str(type), sz, blk->addr,
857 (int)n.len, n.ptr,
858 (int)v.len, v.ptr);
859 else
860 chunk_appendf(chunk, "\t\t[%u] type=%-17s - size=%-6u - addr=%-6u%s\n",
861 pos, htx_blk_type_str(type), sz, blk->addr,
862 (!v.len ? "\t<empty>" : ""));
863 }
864 }
865
866 #endif /* _COMMON_HTX_H */
867
868 /*
869 * Local variables:
870 * c-indent-level: 8
871 * c-basic-offset: 8
872 * End:
873 */
874