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
144 /* HTX flags */
145 #define HTX_FL_NONE 0x00000000
146 #define HTX_FL_PARSING_ERROR 0x00000001 /* Set when a parsing error occurred */
147 #define HTX_FL_UPGRADE 0x00000002 /* Set when an upgrade is in progress */
148 #define HTX_FL_FRAGMENTED 0x00000020 /* Set when the HTX buffer is fragmented */
149
150
151 /* HTX block's type (max 15). */
152 enum htx_blk_type {
153 HTX_BLK_REQ_SL = 0, /* Request start-line */
154 HTX_BLK_RES_SL = 1, /* Response start-line */
155 HTX_BLK_HDR = 2, /* header name/value block */
156 HTX_BLK_EOH = 3, /* end-of-headers block */
157 HTX_BLK_DATA = 4, /* data block */
158 HTX_BLK_TLR = 5, /* trailer name/value block */
159 HTX_BLK_EOT = 6, /* end-of-trailers block */
160 HTX_BLK_EOM = 7, /* end-of-message block */
161 /* 8 .. 14 unused */
162 HTX_BLK_UNUSED = 15, /* unused/removed block */
163 };
164
165 /* One HTX block descriptor */
166 struct htx_blk {
167 uint32_t addr; /* relative storage address of the block's payload */
168 uint32_t info; /* information about the block (type, length) */
169 };
170
171 /* Composite return value used by some HTX functions */
172 struct htx_ret {
173 int32_t ret; /* A numerical value */
174 struct htx_blk *blk; /* An HTX block */
175 };
176
177 /* HTX start-line */
178 struct htx_sl {
179 unsigned int flags; /* HTX_SL_F_* */
180 union {
181 struct {
182 enum http_meth_t meth; /* method */
183 } req;
184 struct {
185 uint16_t status; /* status code */
186 } res;
187 } info;
188
189 /* XXX 2 bytes unused */
190
191 int32_t hdrs_bytes; /* Bytes held by all headers, as seen by the mux
192 * during parsing, from this start-line to the
193 * corresponding EOH. -1 if unknown */
194
195 unsigned int len[3]; /* length of differnt parts of the start-line */
196 char l[0];
197 };
198
199 /* Internal representation of an HTTP message */
200 struct htx {
201 uint32_t size; /* the array size, in bytes, used to store the HTTP message itself */
202 uint32_t data; /* the data size, in bytes. To known to total size used by all allocated
203 * blocks (blocks and their contents), you need to add size used by blocks,
204 * i.e. [ used * sizeof(struct htx_blk *) ] */
205
206 uint32_t used; /* number of blocks in use */
207 uint32_t tail; /* newest inserted block. -1 if the HTX message is empty */
208 uint32_t head; /* oldest inserted block. -1 if the HTX message is empty */
209
210 uint32_t tail_addr; /* start address of the free space in front of the the blocks table */
211 uint32_t head_addr; /* start address of the free space at the beginning */
212 uint32_t end_addr; /* end address of the free space at the beginning */
213
214
215 uint64_t extra; /* known bytes amount remaining to receive */
216 uint32_t flags; /* HTX_FL_* */
217
218 int32_t first; /* position of the first block to (re)start the analyse. -1 if unset. */
219
220 struct htx_blk blocks[0]; /* Blocks representing the HTTP message itself */
221 };
222
223
224 extern struct htx htx_empty;
225
226 struct htx_blk *htx_defrag(struct htx *htx, struct htx_blk *blk, uint32_t info);
227 struct htx_blk *htx_add_blk(struct htx *htx, enum htx_blk_type type, uint32_t blksz);
228 struct htx_blk *htx_remove_blk(struct htx *htx, struct htx_blk *blk);
229 struct htx_ret htx_find_offset(struct htx *htx, uint32_t offset);
230 void htx_truncate(struct htx *htx, uint32_t offset);
231 struct htx_ret htx_drain(struct htx *htx, uint32_t max);
232
233 struct htx_blk *htx_replace_blk_value(struct htx *htx, struct htx_blk *blk,
234 const struct ist old, const struct ist new);
235 struct htx_ret htx_xfer_blks(struct htx *dst, struct htx *src, uint32_t count,
236 enum htx_blk_type mark);
237
238 struct htx_sl *htx_add_stline(struct htx *htx, enum htx_blk_type type, unsigned int flags,
239 const struct ist p1, const struct ist p2, const struct ist p3);
240 struct htx_sl *htx_replace_stline(struct htx *htx, struct htx_blk *blk, const struct ist p1,
241 const struct ist p2, const struct ist p3);
242
243 struct htx_blk *htx_replace_header(struct htx *htx, struct htx_blk *blk,
244 const struct ist name, const struct ist value);
245
246 struct htx_blk *htx_add_header(struct htx *htx, const struct ist name, const struct ist value);
247 struct htx_blk *htx_add_trailer(struct htx *htx, const struct ist name, const struct ist value);
248 struct htx_blk *htx_add_blk_type_size(struct htx *htx, enum htx_blk_type type, uint32_t blksz);
249 struct htx_blk *htx_add_all_headers(struct htx *htx, const struct http_hdr *hdrs);
250 struct htx_blk *htx_add_all_trailers(struct htx *htx, const struct http_hdr *hdrs);
251 struct htx_blk *htx_add_endof(struct htx *htx, enum htx_blk_type type);
252 struct htx_blk *htx_add_data_atonce(struct htx *htx, struct ist data);
253 size_t htx_add_data(struct htx *htx, const struct ist data);
254 struct htx_blk *htx_add_last_data(struct htx *htx, struct ist data);
255 void htx_move_blk_before(struct htx *htx, struct htx_blk **blk, struct htx_blk **ref);
256
257 int htx_reqline_to_h1(const struct htx_sl *sl, struct buffer *chk);
258 int htx_stline_to_h1(const struct htx_sl *sl, struct buffer *chk);
259 int htx_hdr_to_h1(const struct ist n, const struct ist v, struct buffer *chk);
260 int htx_data_to_h1(const struct ist data, struct buffer *chk, int chunked);
261
262 /* Functions and macros to get parts of the start-line or legnth of these
263 * parts. Request and response start-lines are both composed of 3 parts.
264 */
265 #define HTX_SL_LEN(sl) ((sl)->len[0] + (sl)->len[1] + (sl)->len[2])
266
267 #define HTX_SL_P1_LEN(sl) ((sl)->len[0])
268 #define HTX_SL_P2_LEN(sl) ((sl)->len[1])
269 #define HTX_SL_P3_LEN(sl) ((sl)->len[2])
270 #define HTX_SL_P1_PTR(sl) ((sl)->l)
271 #define HTX_SL_P2_PTR(sl) (HTX_SL_P1_PTR(sl) + HTX_SL_P1_LEN(sl))
272 #define HTX_SL_P3_PTR(sl) (HTX_SL_P2_PTR(sl) + HTX_SL_P2_LEN(sl))
273
274 #define HTX_SL_REQ_MLEN(sl) HTX_SL_P1_LEN(sl)
275 #define HTX_SL_REQ_ULEN(sl) HTX_SL_P2_LEN(sl)
276 #define HTX_SL_REQ_VLEN(sl) HTX_SL_P3_LEN(sl)
277 #define HTX_SL_REQ_MPTR(sl) HTX_SL_P1_PTR(sl)
278 #define HTX_SL_REQ_UPTR(sl) HTX_SL_P2_PTR(sl)
279 #define HTX_SL_REQ_VPTR(sl) HTX_SL_P3_PTR(sl)
280
281 #define HTX_SL_RES_VLEN(sl) HTX_SL_P1_LEN(sl)
282 #define HTX_SL_RES_CLEN(sl) HTX_SL_P2_LEN(sl)
283 #define HTX_SL_RES_RLEN(sl) HTX_SL_P3_LEN(sl)
284 #define HTX_SL_RES_VPTR(sl) HTX_SL_P1_PTR(sl)
285 #define HTX_SL_RES_CPTR(sl) HTX_SL_P2_PTR(sl)
286 #define HTX_SL_RES_RPTR(sl) HTX_SL_P3_PTR(sl)
287
htx_sl_p1(const struct htx_sl * sl)288 static inline struct ist htx_sl_p1(const struct htx_sl *sl)
289 {
290 return ist2(HTX_SL_P1_PTR(sl), HTX_SL_P1_LEN(sl));
291 }
292
htx_sl_p2(const struct htx_sl * sl)293 static inline struct ist htx_sl_p2(const struct htx_sl *sl)
294 {
295 return ist2(HTX_SL_P2_PTR(sl), HTX_SL_P2_LEN(sl));
296 }
297
htx_sl_p3(const struct htx_sl * sl)298 static inline struct ist htx_sl_p3(const struct htx_sl *sl)
299 {
300 return ist2(HTX_SL_P3_PTR(sl), HTX_SL_P3_LEN(sl));
301 }
302
htx_sl_req_meth(const struct htx_sl * sl)303 static inline struct ist htx_sl_req_meth(const struct htx_sl *sl)
304 {
305 return htx_sl_p1(sl);
306 }
307
htx_sl_req_uri(const struct htx_sl * sl)308 static inline struct ist htx_sl_req_uri(const struct htx_sl *sl)
309 {
310 return htx_sl_p2(sl);
311 }
312
htx_sl_req_vsn(const struct htx_sl * sl)313 static inline struct ist htx_sl_req_vsn(const struct htx_sl *sl)
314 {
315 return htx_sl_p3(sl);
316 }
317
318
htx_sl_res_vsn(const struct htx_sl * sl)319 static inline struct ist htx_sl_res_vsn(const struct htx_sl *sl)
320 {
321 return htx_sl_p1(sl);
322 }
323
htx_sl_res_code(const struct htx_sl * sl)324 static inline struct ist htx_sl_res_code(const struct htx_sl *sl)
325 {
326 return htx_sl_p2(sl);
327 }
328
htx_sl_res_reason(const struct htx_sl * sl)329 static inline struct ist htx_sl_res_reason(const struct htx_sl *sl)
330 {
331 return htx_sl_p3(sl);
332 }
333
334 /* Converts a position to the corresponding relative address */
htx_pos_to_idx(const struct htx * htx,uint32_t pos)335 static inline uint32_t htx_pos_to_idx(const struct htx *htx, uint32_t pos)
336 {
337 return ((htx->size / sizeof(htx->blocks[0])) - pos - 1);
338 }
339
340 /* Returns the position of the block <blk>. It is the caller responsibility to
341 * be sure <blk> is part of <htx>. */
htx_get_blk_pos(const struct htx * htx,const struct htx_blk * blk)342 static inline uint32_t htx_get_blk_pos(const struct htx *htx, const struct htx_blk *blk)
343 {
344 return (htx->blocks + (htx->size / sizeof(htx->blocks[0])) - blk - 1);
345 }
346
347 /* Returns the block at the position <pos>. It is the caller responsibility to
348 * be sure the block at the position <pos> exists. */
htx_get_blk(const struct htx * htx,uint32_t pos)349 static inline struct htx_blk *htx_get_blk(const struct htx *htx, uint32_t pos)
350 {
351 return ((struct htx_blk *)(htx->blocks) + htx_pos_to_idx(htx, pos));
352 }
353
354 /* Returns the type of the block <blk> */
htx_get_blk_type(const struct htx_blk * blk)355 static inline enum htx_blk_type htx_get_blk_type(const struct htx_blk *blk)
356 {
357 return (blk->info >> 28);
358 }
359
360 /* Returns the size of the block <blk>, depending of its type */
htx_get_blksz(const struct htx_blk * blk)361 static inline uint32_t htx_get_blksz(const struct htx_blk *blk)
362 {
363 enum htx_blk_type type = htx_get_blk_type(blk);
364
365 switch (type) {
366 case HTX_BLK_HDR:
367 case HTX_BLK_TLR:
368 /* name.length + value.length */
369 return ((blk->info & 0xff) + ((blk->info >> 8) & 0xfffff));
370 default:
371 /* value.length */
372 return (blk->info & 0xfffffff);
373 }
374 }
375
376 /* Returns the position of the oldest entry (head).
377 *
378 * An signed 32-bits integer is returned to handle -1 case. Blocks position are
379 * store on unsigned 32-bits integer, but it is impossible to have so much
380 * blocks to overflow a 32-bits signed integer !
381 */
htx_get_head(const struct htx * htx)382 static inline int32_t htx_get_head(const struct htx *htx)
383 {
384 return (htx->used ? htx->head : -1);
385 }
386
387 /* Returns the oldest HTX block (head) if the HTX message is not
388 * empty. Otherwise it returns NULL.
389 */
htx_get_head_blk(const struct htx * htx)390 static inline struct htx_blk *htx_get_head_blk(const struct htx *htx)
391 {
392 int32_t head = htx_get_head(htx);
393
394 return ((head == -1) ? NULL : htx_get_blk(htx, head));
395 }
396
397 /* Returns the type of the oldest HTX block (head) if the HTX message is not
398 * empty. Otherwise it returns HTX_BLK_UNUSED.
399 */
htx_get_head_type(const struct htx * htx)400 static inline enum htx_blk_type htx_get_head_type(const struct htx *htx)
401 {
402 struct htx_blk *blk = htx_get_head_blk(htx);
403
404 return (blk ? htx_get_blk_type(blk) : HTX_BLK_UNUSED);
405 }
406
407 /* Returns the position of the newest entry (tail).
408 *
409 * An signed 32-bits integer is returned to handle -1 case. Blocks position are
410 * store on unsigned 32-bits integer, but it is impossible to have so much
411 * blocks to overflow a 32-bits signed integer !
412 */
htx_get_tail(const struct htx * htx)413 static inline int32_t htx_get_tail(const struct htx *htx)
414 {
415 return (htx->used ? htx->tail : -1);
416 }
417
418 /* Returns the newest HTX block (tail) if the HTX message is not
419 * empty. Otherwise it returns NULL.
420 */
htx_get_tail_blk(const struct htx * htx)421 static inline struct htx_blk *htx_get_tail_blk(const struct htx *htx)
422 {
423 int32_t tail = htx_get_tail(htx);
424
425 return ((tail == -1) ? NULL : htx_get_blk(htx, tail));
426 }
427
428 /* Returns the type of the newest HTX block (tail) if the HTX message is not
429 * empty. Otherwise it returns HTX_BLK_UNUSED.
430 */
htx_get_tail_type(const struct htx * htx)431 static inline enum htx_blk_type htx_get_tail_type(const struct htx *htx)
432 {
433 struct htx_blk *blk = htx_get_tail_blk(htx);
434
435 return (blk ? htx_get_blk_type(blk) : HTX_BLK_UNUSED);
436 }
437
438 /* Returns the position of the first block in the HTX message <htx>. If unset,
439 * or if <htx> is empty, -1 is returned.
440 *
441 * An signed 32-bits integer is returned to handle -1 case. Blocks position are
442 * store on unsigned 32-bits integer, but it is impossible to have so much
443 * blocks to overflow a 32-bits signed integer !
444 */
htx_get_first(const struct htx * htx)445 static inline int32_t htx_get_first(const struct htx *htx)
446 {
447 if (!htx->used)
448 return -1;
449 return htx->first;
450 }
451
452 /* Returns the first HTX block in the HTX message <htx>. If unset or if <htx> is
453 * empty, NULL returned.
454 */
htx_get_first_blk(const struct htx * htx)455 static inline struct htx_blk *htx_get_first_blk(const struct htx *htx)
456 {
457 int32_t pos;
458
459 pos = htx_get_first(htx);
460 return ((pos == -1) ? NULL : htx_get_blk(htx, pos));
461 }
462
463 /* Returns the type of the first block in the HTX message <htx>. If unset or if
464 * <htx> is empty, HTX_BLK_UNUSED is returned.
465 */
htx_get_first_type(const struct htx * htx)466 static inline enum htx_blk_type htx_get_first_type(const struct htx *htx)
467 {
468 struct htx_blk *blk = htx_get_first_blk(htx);
469
470 return (blk ? htx_get_blk_type(blk) : HTX_BLK_UNUSED);
471 }
472
473 /* Returns the position of block immediately before the one pointed by <pos>. If
474 * the message is empty or if <pos> is the position of the head, -1 returned.
475 *
476 * An signed 32-bits integer is returned to handle -1 case. Blocks position are
477 * store on unsigned 32-bits integer, but it is impossible to have so much
478 * blocks to overflow a 32-bits signed integer !
479 */
htx_get_prev(const struct htx * htx,uint32_t pos)480 static inline int32_t htx_get_prev(const struct htx *htx, uint32_t pos)
481 {
482 int32_t head;
483
484 head = htx_get_head(htx);
485 if (head == -1 || pos == head)
486 return -1;
487 return (pos - 1);
488 }
489
490 /* Returns the HTX block before <blk> in the HTX message <htx>. If <blk> is the
491 * head, NULL returned.
492 */
htx_get_prev_blk(const struct htx * htx,const struct htx_blk * blk)493 static inline struct htx_blk *htx_get_prev_blk(const struct htx *htx,
494 const struct htx_blk *blk)
495 {
496 int32_t pos;
497
498 pos = htx_get_prev(htx, htx_get_blk_pos(htx, blk));
499 return ((pos == -1) ? NULL : htx_get_blk(htx, pos));
500 }
501
502 /* Returns the position of block immediately after the one pointed by <pos>. If
503 * the message is empty or if <pos> is the position of the tail, -1 returned.
504 *
505 * An signed 32-bits integer is returned to handle -1 case. Blocks position are
506 * store on unsigned 32-bits integer, but it is impossible to have so much
507 * blocks to overflow a 32-bits signed integer !
508 */
htx_get_next(const struct htx * htx,uint32_t pos)509 static inline int32_t htx_get_next(const struct htx *htx, uint32_t pos)
510 {
511 if (!htx->used || pos == htx->tail)
512 return -1;
513 return (pos + 1);
514
515 }
516
517 /* Returns the HTX block after <blk> in the HTX message <htx>. If <blk> is the
518 * tail, NULL returned.
519 */
htx_get_next_blk(const struct htx * htx,const struct htx_blk * blk)520 static inline struct htx_blk *htx_get_next_blk(const struct htx *htx,
521 const struct htx_blk *blk)
522 {
523 int32_t pos;
524
525 pos = htx_get_next(htx, htx_get_blk_pos(htx, blk));
526 return ((pos == -1) ? NULL : htx_get_blk(htx, pos));
527 }
528
529 /* Changes the size of the value. It is the caller responsibility to change the
530 * value itself, make sure there is enough space and update allocated
531 * value. This function updates the HTX message accordingly.
532 */
htx_change_blk_value_len(struct htx * htx,struct htx_blk * blk,uint32_t newlen)533 static inline void htx_change_blk_value_len(struct htx *htx, struct htx_blk *blk, uint32_t newlen)
534 {
535 enum htx_blk_type type = htx_get_blk_type(blk);
536 uint32_t oldlen, sz;
537 int32_t delta;
538
539 sz = htx_get_blksz(blk);
540 switch (type) {
541 case HTX_BLK_HDR:
542 case HTX_BLK_TLR:
543 oldlen = (blk->info >> 8) & 0xfffff;
544 blk->info = (type << 28) + (newlen << 8) + (blk->info & 0xff);
545 break;
546 default:
547 oldlen = blk->info & 0xfffffff;
548 blk->info = (type << 28) + newlen;
549 break;
550 }
551
552 /* Update HTTP message */
553 delta = (newlen - oldlen);
554 htx->data += delta;
555 if (blk->addr+sz == htx->tail_addr)
556 htx->tail_addr += delta;
557 else if (blk->addr+sz == htx->head_addr)
558 htx->head_addr += delta;
559 }
560
561 /* Changes the size of the value. It is the caller responsibility to change the
562 * value itself, make sure there is enough space and update allocated
563 * value. Unlike the function htx_change_blk_value_len(), this one does not
564 * update the HTX message. So it should be used with caution.
565 */
htx_set_blk_value_len(struct htx_blk * blk,uint32_t vlen)566 static inline void htx_set_blk_value_len(struct htx_blk *blk, uint32_t vlen)
567 {
568 enum htx_blk_type type = htx_get_blk_type(blk);
569
570 switch (type) {
571 case HTX_BLK_HDR:
572 case HTX_BLK_TLR:
573 blk->info = (type << 28) + (vlen << 8) + (blk->info & 0xff);
574 break;
575 case HTX_BLK_REQ_SL:
576 case HTX_BLK_RES_SL:
577 case HTX_BLK_DATA:
578 blk->info = (type << 28) + vlen;
579 break;
580 default:
581 /* Unexpected case */
582 break;
583 }
584 }
585
586 /* Returns the data pointer of the block <blk> */
htx_get_blk_ptr(const struct htx * htx,const struct htx_blk * blk)587 static inline void *htx_get_blk_ptr(const struct htx *htx, const struct htx_blk *blk)
588 {
589 return ((void *)htx->blocks + blk->addr);
590 }
591
592 /* Returns the name of the block <blk>, only if it is a header or a
593 * trailer. Otherwise it returns an empty string.
594 */
htx_get_blk_name(const struct htx * htx,const struct htx_blk * blk)595 static inline struct ist htx_get_blk_name(const struct htx *htx, const struct htx_blk *blk)
596 {
597 enum htx_blk_type type = htx_get_blk_type(blk);
598 struct ist ret;
599
600 switch (type) {
601 case HTX_BLK_HDR:
602 case HTX_BLK_TLR:
603 ret.ptr = htx_get_blk_ptr(htx, blk);
604 ret.len = blk->info & 0xff;
605 break;
606
607 default:
608 return ist("");
609 }
610 return ret;
611 }
612
613
614 /* Returns the value of the block <blk>, depending on its type. If there is no
615 * value (for end-of blocks), an empty one is retruned.
616 */
htx_get_blk_value(const struct htx * htx,const struct htx_blk * blk)617 static inline struct ist htx_get_blk_value(const struct htx *htx, const struct htx_blk *blk)
618 {
619 enum htx_blk_type type = htx_get_blk_type(blk);
620 struct ist ret;
621
622 switch (type) {
623 case HTX_BLK_HDR:
624 case HTX_BLK_TLR:
625 ret.ptr = htx_get_blk_ptr(htx, blk) + (blk->info & 0xff);
626 ret.len = (blk->info >> 8) & 0xfffff;
627 break;
628
629 case HTX_BLK_REQ_SL:
630 case HTX_BLK_RES_SL:
631 case HTX_BLK_DATA:
632 ret.ptr = htx_get_blk_ptr(htx, blk);
633 ret.len = blk->info & 0xfffffff;
634 break;
635
636 default:
637 return ist("");
638 }
639 return ret;
640 }
641
642 /* Removes <n> bytes from the beginning of DATA block <blk>. The block's start
643 * address and its length are adjusted, and the htx's total data count is
644 * updated. This is used to mark that part of some data were transfered
645 * from a DATA block without removing this DATA block. No sanity check is
646 * performed, the caller is reponsible for doing this exclusively on DATA
647 * blocks, and never removing more than the block's size.
648 */
htx_cut_data_blk(struct htx * htx,struct htx_blk * blk,uint32_t n)649 static inline void htx_cut_data_blk(struct htx *htx, struct htx_blk *blk, uint32_t n)
650 {
651 if (blk->addr == htx->end_addr)
652 htx->end_addr += n;
653 blk->addr += n;
654 blk->info -= n;
655 htx->data -= n;
656 }
657
658 /* Returns the space used by metadata in <htx>. */
htx_meta_space(const struct htx * htx)659 static inline uint32_t htx_meta_space(const struct htx *htx)
660 {
661 return (htx->used * sizeof(htx->blocks[0]));
662 }
663
664 /* Returns the space used (payload + metadata) in <htx> */
htx_used_space(const struct htx * htx)665 static inline uint32_t htx_used_space(const struct htx *htx)
666 {
667 return (htx->data + htx_meta_space(htx));
668 }
669
670 /* Returns the free space in <htx> */
htx_free_space(const struct htx * htx)671 static inline uint32_t htx_free_space(const struct htx *htx)
672 {
673 return (htx->size - htx_used_space(htx));
674 }
675
676 /* Returns the maximum size available to store some data in <htx> if a new block
677 * is reserved.
678 */
htx_free_data_space(const struct htx * htx)679 static inline uint32_t htx_free_data_space(const struct htx *htx)
680 {
681 uint32_t free = htx_free_space(htx);
682
683 if (free < sizeof(htx->blocks[0]))
684 return 0;
685 return (free - sizeof(htx->blocks[0]));
686 }
687
688 /* Returns non-zero only if the HTX message free space wraps */
htx_space_wraps(const struct htx * htx)689 static inline int htx_space_wraps(const struct htx *htx)
690 {
691 uint32_t headroom, tailroom;
692
693 headroom = (htx->end_addr - htx->head_addr);
694 tailroom = sizeof(htx->blocks[0]) * htx_pos_to_idx(htx, htx->tail) - htx->tail_addr;
695
696 return (headroom && tailroom);
697 }
698
699 /* Returns the maximum size for a block, not exceeding <max> bytes. <max> may be
700 * set to -1 to have no limit.
701 */
htx_get_max_blksz(const struct htx * htx,int32_t max)702 static inline uint32_t htx_get_max_blksz(const struct htx *htx, int32_t max)
703 {
704 uint32_t free = htx_free_space(htx);
705
706 if (max != -1 && free > max)
707 free = max;
708 if (free < sizeof(htx->blocks[0]))
709 return 0;
710 return (free - sizeof(htx->blocks[0]));
711 }
712
713 /* Returns 1 if the message has less than 1/4 of its capacity free, otherwise 0 */
htx_almost_full(const struct htx * htx)714 static inline int htx_almost_full(const struct htx *htx)
715 {
716 if (!htx->size || htx_free_space(htx) < htx->size / 4)
717 return 1;
718 return 0;
719 }
720
721 /* Resets an HTX message */
htx_reset(struct htx * htx)722 static inline void htx_reset(struct htx *htx)
723 {
724 htx->data = htx->used = htx->tail = htx->head = 0;
725 htx->tail_addr = htx->head_addr = htx->end_addr = 0;
726 htx->extra = 0;
727 htx->flags = HTX_FL_NONE;
728 htx->first = -1;
729 }
730
731 /* Returns the available room for raw data in buffer <buf> once HTX overhead is
732 * taken into account (one HTX header and two blocks). The purpose is to figure
733 * the optimal fill length to avoid copies.
734 */
buf_room_for_htx_data(const struct buffer * buf)735 static inline size_t buf_room_for_htx_data(const struct buffer *buf)
736 {
737 size_t room;
738
739 room = b_room(buf);
740 if (room <= sizeof(struct htx) + 2 * sizeof(struct htx_blk))
741 room = 0;
742 else
743 room -= sizeof(struct htx) + 2 * sizeof(struct htx_blk);
744
745 return room;
746 }
747
748
749 /* Returns an HTX message using the buffer <buf>. Unlike htx_from_buf(), this
750 * function does not update the buffer. So if the HTX message is updated, the
751 * caller must call htx_to_buf() to be sure to also update the underlying buffer
752 * accordingly. Note that it always returns a valid pointer, either to an
753 * initialized buffer or to the empty buffer. This function must always be
754 * called with a buffer containing an HTX message (or an empty buffer).
755 */
htxbuf(const struct buffer * buf)756 static inline struct htx *htxbuf(const struct buffer *buf)
757 {
758 struct htx *htx;
759
760 if (b_is_null(buf))
761 return &htx_empty;
762 htx = ((struct htx *)(buf->area));
763 if (!b_data(buf)) {
764 htx->size = buf->size - sizeof(*htx);
765 htx_reset(htx);
766 }
767 return htx;
768 }
769
770 /* Returns an HTX message using the buffer <buf>. <buf> is updated to appear as
771 * full. It should be used when you want to add something into the HTX message,
772 * so the call to htx_to_buf() may be skipped. But, it is the caller
773 * responsibility to call htx_to_buf() to reset <buf> if it is relevant. The
774 * returned pointer is always valid. This function must always be called with a
775 * buffer containing an HTX message (or an empty buffer).
776 *
777 * The caller can call htxbuf() function to avoid any update of the buffer.
778 */
htx_from_buf(struct buffer * buf)779 static inline struct htx *htx_from_buf(struct buffer *buf)
780 {
781 struct htx *htx = htxbuf(buf);
782
783 b_set_data(buf, b_size(buf));
784 return htx;
785 }
786
787 /* Update <buf> accordingly to the HTX message <htx> */
htx_to_buf(struct htx * htx,struct buffer * buf)788 static inline void htx_to_buf(struct htx *htx, struct buffer *buf)
789 {
790 if (!htx->used && !(htx->flags & (HTX_FL_PARSING_ERROR|HTX_FL_UPGRADE))) {
791 htx_reset(htx);
792 b_set_data(buf, 0);
793 }
794 else
795 b_set_data(buf, b_size(buf));
796 }
797
798 /* Returns 1 if the message is empty, otherwise it returns 0. Note that it is
799 * illegal to call this with htx == NULL.
800 */
htx_is_empty(const struct htx * htx)801 static inline int htx_is_empty(const struct htx *htx)
802 {
803 return !htx->used;
804 }
805
806 /* Returns 1 if the message is not empty, otherwise it returns 0. Note that it
807 * is illegal to call this with htx == NULL.
808 */
htx_is_not_empty(const struct htx * htx)809 static inline int htx_is_not_empty(const struct htx *htx)
810 {
811 return htx->used;
812 }
813
htx_skip_msg_payload(struct htx * htx)814 static inline void htx_skip_msg_payload(struct htx *htx)
815 {
816 struct htx_blk *blk = htx_get_first_blk(htx);
817
818 while (blk) {
819 enum htx_blk_type type = htx_get_blk_type(blk);
820
821 blk = ((type > HTX_BLK_EOH && type < HTX_BLK_EOM)
822 ? htx_remove_blk(htx, blk)
823 : htx_get_next_blk(htx, blk));
824 }
825 }
826
827 /* For debugging purpose */
htx_blk_type_str(enum htx_blk_type type)828 static inline const char *htx_blk_type_str(enum htx_blk_type type)
829 {
830 switch (type) {
831 case HTX_BLK_REQ_SL: return "HTX_BLK_REQ_SL";
832 case HTX_BLK_RES_SL: return "HTX_BLK_RES_SL";
833 case HTX_BLK_HDR: return "HTX_BLK_HDR";
834 case HTX_BLK_EOH: return "HTX_BLK_EOH";
835 case HTX_BLK_DATA: return "HTX_BLK_DATA";
836 case HTX_BLK_TLR: return "HTX_BLK_TLR";
837 case HTX_BLK_EOT: return "HTX_BLK_EOT";
838 case HTX_BLK_EOM: return "HTX_BLK_EOM";
839 case HTX_BLK_UNUSED: return "HTX_BLK_UNUSED";
840 default: return "HTX_BLK_???";
841 };
842 }
843
844 /* For debugging purpose */
htx_dump(struct htx * htx)845 static inline void htx_dump(struct htx *htx)
846 {
847 int32_t pos;
848
849 fprintf(stderr, "htx:%p [ size=%u - data=%u - used=%u - wrap=%s - extra=%llu]\n",
850 htx, htx->size, htx->data, htx->used, (!htx->head_addr) ? "NO" : "YES",
851 (unsigned long long)htx->extra);
852 fprintf(stderr, "\tfirst=%d - head=%u, tail=%u\n",
853 htx->first, htx->head, htx->tail);
854 fprintf(stderr, "\ttail_addr=%d - head_addr=%u, end_addr=%u\n",
855 htx->tail_addr, htx->head_addr, htx->end_addr);
856
857 for (pos = htx_get_head(htx); pos != -1; pos = htx_get_next(htx, pos)) {
858 struct htx_sl *sl;
859 struct htx_blk *blk = htx_get_blk(htx, pos);
860 enum htx_blk_type type = htx_get_blk_type(blk);
861 uint32_t sz = htx_get_blksz(blk);
862 struct ist n, v;
863
864 n = htx_get_blk_name(htx, blk);
865 v = htx_get_blk_value(htx, blk);
866
867 if (type == HTX_BLK_REQ_SL || type == HTX_BLK_RES_SL) {
868 sl = htx_get_blk_ptr(htx, blk);
869 fprintf(stderr, "\t\t[%u] type=%-17s - size=%-6u - addr=%-6u\t%.*s %.*s %.*s\n",
870 pos, htx_blk_type_str(type), sz, blk->addr,
871 HTX_SL_P1_LEN(sl), HTX_SL_P1_PTR(sl),
872 HTX_SL_P2_LEN(sl), HTX_SL_P2_PTR(sl),
873 HTX_SL_P3_LEN(sl), HTX_SL_P3_PTR(sl));
874 }
875 else if (type == HTX_BLK_HDR || type == HTX_BLK_TLR)
876 fprintf(stderr, "\t\t[%u] type=%-17s - size=%-6u - addr=%-6u\t%.*s: %.*s\n",
877 pos, htx_blk_type_str(type), sz, blk->addr,
878 (int)n.len, n.ptr,
879 (int)v.len, v.ptr);
880 else
881 fprintf(stderr, "\t\t[%u] type=%-17s - size=%-6u - addr=%-6u%s\n",
882 pos, htx_blk_type_str(type), sz, blk->addr,
883 (!v.len ? "\t<empty>" : ""));
884 }
885 fprintf(stderr, "\n");
886 }
887
888 #endif /* _COMMON_HTX_H */
889
890 /*
891 * Local variables:
892 * c-indent-level: 8
893 * c-basic-offset: 8
894 * End:
895 */
896