lsquic_frame_reader.c revision 08c45823
1/* Copyright (c) 2017 - 2020 LiteSpeed Technologies Inc. See LICENSE. */ 2/* 3 * lsquic_frame_reader.c -- Read HTTP frames from stream 4 */ 5 6#ifndef WIN32 7#include <arpa/inet.h> 8#endif 9#include <assert.h> 10#include <ctype.h> 11#include <errno.h> 12#include <inttypes.h> 13#include <stdlib.h> 14#include <string.h> 15#include <sys/queue.h> 16 17#include "lshpack.h" 18#include "lsquic.h" 19#include "lsquic_mm.h" 20#include "lsquic_frame_common.h" 21#include "lsquic_frame_reader.h" 22#include "lsquic_http1x_if.h" 23#include "lsquic_headers.h" 24#include "lsquic_ev_log.h" 25#include "lsquic_hash.h" 26#include "lsquic_conn.h" 27 28#define LSQUIC_LOGGER_MODULE LSQLM_FRAME_READER 29#define LSQUIC_LOG_CONN_ID lsquic_conn_log_cid(lsquic_stream_conn(\ 30 fr->fr_stream)) 31#include "lsquic_logger.h" 32 33 34/* headers_state is used by HEADERS, PUSH_PROMISE, and CONTINUATION frames */ 35struct headers_state 36{ 37 enum http_frame_type 38 frame_type; 39 unsigned nread; /* Not counting pesw, only payload and padding */ 40 41 /* Values parsed out from pesw buffer: */ 42 uint32_t oth_stream_id; /* For HEADERS: ID of stream we depend on; 43 * for PUSH_PROMISE: promised stream ID. 44 */ 45 unsigned short weight; /* HEADERS only */ 46 signed char exclusive; /* HEADERS only */ 47 unsigned char pad_length; 48 49 unsigned char pseh; 50 51 /* PESW: Pad length, Exclusive, Stream Dependency, Weight. This is at 52 * most six bytes for HEADERS frame (RFC 7540, page 33) and five bytes 53 * for PUSH_PROMISE frame (Ibid, p. 40). 54 */ 55 unsigned char pesw_size; 56 unsigned char pesw_nread; 57 unsigned char pesw[6]; 58}; 59 60 61struct settings_state 62{ /* RFC 7540, Section 6.5.1 */ 63 unsigned char nread; 64 unsigned char set_buf[2 + 4]; /* We'll read one setting at a time */ 65}; 66 67 68struct priority_state 69{ /* RFC 7540, Section 6.3 */ 70 unsigned char nread; 71 union { 72 unsigned char prio_buf[sizeof(struct http_prio_frame)]; 73 struct http_prio_frame prio_frame; 74 } u; 75}; 76 77 78struct skip_state 79{ 80 uint32_t n_skipped; 81}; 82 83 84struct reader_state 85{ 86 unsigned nh_read; /* Number of bytes of header read */ 87 struct http_frame_header header; 88 enum { 89 READER_SKIP, 90 READER_HEADERS, 91 READER_PUSH_PROMISE, 92 READER_CONTIN, 93 READER_SETTINGS, 94 READER_PRIORITY, 95 } reader_type; 96 unsigned payload_length; 97 union { 98 struct headers_state headers_state; 99 struct skip_state skip_state; 100 struct settings_state settings_state; 101 struct priority_state priority_state; 102 } by_type; 103}; 104 105 106struct lsquic_frame_reader 107{ 108 struct lsquic_mm *fr_mm; 109 struct lshpack_dec *fr_hdec; 110 struct lsquic_stream *fr_stream; 111 fr_stream_read_f fr_read; 112 const struct frame_reader_callbacks 113 *fr_callbacks; 114 void *fr_cb_ctx; 115 const struct lsquic_hset_if *fr_hsi_if; 116 void *fr_hsi_ctx; 117 struct http1x_ctor_ctx fr_h1x_ctor_ctx; 118 /* The the header block is shared between HEADERS, PUSH_PROMISE, and 119 * CONTINUATION frames. It gets added to as block fragments come in. 120 */ 121 unsigned char *fr_header_block; 122#if LSQUIC_CONN_STATS 123 struct conn_stats *fr_conn_stats; 124#endif 125 unsigned fr_header_block_sz; 126 unsigned fr_max_headers_sz; /* 0 means no limit */ 127 enum frame_reader_flags fr_flags; 128 /* Keep some information about previous frame to catch framing errors. 129 */ 130 uint32_t fr_prev_stream_id; 131 enum http_frame_header_flags fr_prev_hfh_flags:8; 132 enum http_frame_type fr_prev_frame_type:8; 133 struct reader_state fr_state; 134}; 135 136 137#define reset_state(fr) do { \ 138 LSQ_DEBUG("reset state"); \ 139 (fr)->fr_state.nh_read = 0; \ 140} while (0) 141 142 143static uint32_t 144fr_get_stream_id (const struct lsquic_frame_reader *fr) 145{ 146 uint32_t stream_id; 147 assert(fr->fr_state.nh_read >= sizeof(fr->fr_state.header)); 148 memcpy(&stream_id, fr->fr_state.header.hfh_stream_id, sizeof(stream_id)); 149 stream_id = ntohl(stream_id); 150 return stream_id; 151} 152 153 154static const char * 155hft_to_string (enum http_frame_type hft) 156{ 157 static const char *const map[] = { 158 [HTTP_FRAME_DATA] = "HTTP_FRAME_DATA", 159 [HTTP_FRAME_HEADERS] = "HTTP_FRAME_HEADERS", 160 [HTTP_FRAME_PRIORITY] = "HTTP_FRAME_PRIORITY", 161 [HTTP_FRAME_RST_STREAM] = "HTTP_FRAME_RST_STREAM", 162 [HTTP_FRAME_SETTINGS] = "HTTP_FRAME_SETTINGS", 163 [HTTP_FRAME_PUSH_PROMISE] = "HTTP_FRAME_PUSH_PROMISE", 164 [HTTP_FRAME_PING] = "HTTP_FRAME_PING", 165 [HTTP_FRAME_GOAWAY] = "HTTP_FRAME_GOAWAY", 166 [HTTP_FRAME_WINDOW_UPDATE] = "HTTP_FRAME_WINDOW_UPDATE", 167 [HTTP_FRAME_CONTINUATION] = "HTTP_FRAME_CONTINUATION", 168 }; 169 if (hft < N_HTTP_FRAME_TYPES) 170 return map[hft]; 171 else 172 return "<unknown>"; 173} 174 175 176struct lsquic_frame_reader * 177lsquic_frame_reader_new (enum frame_reader_flags flags, 178 unsigned max_headers_sz, 179 struct lsquic_mm *mm, 180 struct lsquic_stream *stream, fr_stream_read_f read, 181 struct lshpack_dec *hdec, 182 const struct frame_reader_callbacks *cb, 183 void *frame_reader_cb_ctx, 184#if LSQUIC_CONN_STATS 185 struct conn_stats *conn_stats, 186#endif 187 const struct lsquic_hset_if *hsi_if, void *hsi_ctx) 188{ 189 struct lsquic_frame_reader *fr = malloc(sizeof(*fr)); 190 if (!fr) 191 return NULL; 192 fr->fr_mm = mm; 193 fr->fr_hdec = hdec; 194 fr->fr_flags = flags; 195 fr->fr_stream = stream; 196 fr->fr_read = read; 197 fr->fr_callbacks = cb; 198 fr->fr_cb_ctx = frame_reader_cb_ctx; 199 fr->fr_header_block = NULL; 200 fr->fr_max_headers_sz = max_headers_sz; 201 fr->fr_hsi_if = hsi_if; 202 if (hsi_if == lsquic_http1x_if) 203 { 204 fr->fr_h1x_ctor_ctx = (struct http1x_ctor_ctx) { 205 .conn = lsquic_stream_conn(stream), 206 .max_headers_sz = fr->fr_max_headers_sz, 207 .is_server = fr->fr_flags & FRF_SERVER, 208 }; 209 fr->fr_hsi_ctx = &fr->fr_h1x_ctor_ctx; 210 } 211 else 212 fr->fr_hsi_ctx = hsi_ctx; 213 reset_state(fr); 214#if LSQUIC_CONN_STATS 215 fr->fr_conn_stats = conn_stats; 216#endif 217 return fr; 218} 219 220 221void 222lsquic_frame_reader_destroy (struct lsquic_frame_reader *fr) 223{ 224 free(fr->fr_header_block); 225 free(fr); 226} 227 228 229#define RETURN_ERROR(nread) do { \ 230 assert(nread <= 0); \ 231 if (0 == nread) \ 232 { \ 233 LSQ_INFO("%s: unexpected EOF", __func__); \ 234 return -1; \ 235 } \ 236 else \ 237 { \ 238 LSQ_WARN("%s: error reading from stream: %s", __func__, \ 239 strerror(errno)); \ 240 return -1; \ 241 } \ 242} while (0) 243 244 245static int 246prepare_for_payload (struct lsquic_frame_reader *fr) 247{ 248 uint32_t stream_id; 249 unsigned char *header_block; 250 251 /* RFC 7540, Section 4.1: Ignore R bit: */ 252 fr->fr_state.header.hfh_stream_id[0] &= ~0x80; 253 254 fr->fr_state.payload_length = hfh_get_length(&fr->fr_state.header); 255 256 stream_id = fr_get_stream_id(fr); 257 258 if (fr->fr_state.header.hfh_type != HTTP_FRAME_CONTINUATION && 259 (fr->fr_flags & FRF_HAVE_PREV) && 260 (fr->fr_prev_frame_type == HTTP_FRAME_HEADERS || 261 fr->fr_prev_frame_type == HTTP_FRAME_PUSH_PROMISE || 262 fr->fr_prev_frame_type == HTTP_FRAME_CONTINUATION ) && 263 0 == (fr->fr_prev_hfh_flags & HFHF_END_HEADERS)) 264 { 265 LSQ_INFO("Framing error: expected CONTINUATION frame, got %u", 266 fr->fr_state.header.hfh_type); 267 fr->fr_callbacks->frc_on_error(fr->fr_cb_ctx, stream_id, 268 FR_ERR_EXPECTED_CONTIN); 269 return -1; 270 } 271 272 switch (fr->fr_state.header.hfh_type) 273 { 274 case HTTP_FRAME_HEADERS: 275 if (fr->fr_max_headers_sz && 276 fr->fr_state.payload_length > fr->fr_max_headers_sz) 277 goto headers_too_large; 278 fr->fr_state.by_type.headers_state.frame_type = HTTP_FRAME_HEADERS; 279 fr->fr_state.by_type.headers_state.nread = 0; 280 fr->fr_state.by_type.headers_state.pesw_nread = 0; 281 fr->fr_state.by_type.headers_state.pseh = 0; 282 if (fr->fr_state.header.hfh_flags & HFHF_PADDED) 283 fr->fr_state.by_type.headers_state.pesw_size = 1; 284 else 285 { 286 fr->fr_state.by_type.headers_state.pad_length = 0; 287 fr->fr_state.by_type.headers_state.pesw_size = 0; 288 } 289 if (fr->fr_state.header.hfh_flags & HFHF_PRIORITY) 290 fr->fr_state.by_type.headers_state.pesw_size += 5; 291 else 292 { 293 fr->fr_state.by_type.headers_state.exclusive = -1; 294 fr->fr_state.by_type.headers_state.oth_stream_id = 0; 295 fr->fr_state.by_type.headers_state.weight = 0; 296 } 297 LSQ_DEBUG("pesw size: %u; payload length: %u; flags: 0x%X", 298 fr->fr_state.by_type.headers_state.pesw_size, 299 fr->fr_state.payload_length, fr->fr_state.header.hfh_flags); 300 if (fr->fr_state.by_type.headers_state.pesw_size > 301 fr->fr_state.payload_length) 302 { 303 LSQ_INFO("Invalid headers frame: payload length too small"); 304 errno = EBADMSG; 305 return -1; 306 } 307 fr->fr_state.reader_type = READER_HEADERS; 308 break; 309 case HTTP_FRAME_PUSH_PROMISE: 310 if (fr->fr_flags & FRF_SERVER) 311 { 312 LSQ_INFO("clients should not push promised"); 313 fr->fr_callbacks->frc_on_error(fr->fr_cb_ctx, stream_id, 314 FR_ERR_UNEXPECTED_PUSH); 315 return -1; 316 } 317 if (fr->fr_max_headers_sz && 318 fr->fr_state.payload_length > fr->fr_max_headers_sz) 319 goto headers_too_large; 320 fr->fr_state.by_type.headers_state.frame_type = HTTP_FRAME_PUSH_PROMISE; 321 fr->fr_state.by_type.headers_state.nread = 0; 322 fr->fr_state.by_type.headers_state.pesw_nread = 0; 323 fr->fr_state.by_type.headers_state.pseh = 0; 324 if (fr->fr_state.header.hfh_flags & HFHF_PADDED) 325 fr->fr_state.by_type.headers_state.pesw_size = 5; 326 else 327 { 328 fr->fr_state.by_type.headers_state.pad_length = 0; 329 fr->fr_state.by_type.headers_state.pesw_size = 4; 330 } 331 LSQ_DEBUG("pesw size: %u; payload length: %u; flags: 0x%X", 332 fr->fr_state.by_type.headers_state.pesw_size, 333 fr->fr_state.payload_length, fr->fr_state.header.hfh_flags); 334 if (fr->fr_state.by_type.headers_state.pesw_size > 335 fr->fr_state.payload_length) 336 { 337 LSQ_INFO("Invalid headers frame: payload length too small"); 338 errno = EBADMSG; 339 return -1; 340 } 341 fr->fr_state.reader_type = READER_PUSH_PROMISE; 342 break; 343 case HTTP_FRAME_CONTINUATION: 344 if (0 == (fr->fr_flags & FRF_HAVE_PREV)) 345 { 346 LSQ_INFO("Framing error: unexpected CONTINUATION"); 347 return -1; 348 } 349 if (!(fr->fr_prev_frame_type == HTTP_FRAME_HEADERS || 350 fr->fr_prev_frame_type == HTTP_FRAME_PUSH_PROMISE || 351 fr->fr_prev_frame_type == HTTP_FRAME_CONTINUATION)) 352 { 353 LSQ_INFO("Framing error: unexpected CONTINUATION"); 354 return -1; 355 } 356 if (fr->fr_prev_hfh_flags & HFHF_END_HEADERS) 357 { 358 LSQ_INFO("Framing error: unexpected CONTINUATION"); 359 return -1; 360 } 361 if (stream_id != fr->fr_prev_stream_id) 362 { 363 LSQ_INFO("Framing error: CONTINUATION does not have matching " 364 "stream ID"); 365 return -1; 366 } 367 if (fr->fr_state.reader_type == READER_SKIP) 368 goto continue_skipping; 369 fr->fr_header_block_sz += fr->fr_state.payload_length; 370 if (fr->fr_max_headers_sz && 371 fr->fr_header_block_sz > fr->fr_max_headers_sz) 372 { 373 free(fr->fr_header_block); 374 fr->fr_header_block = NULL; 375 goto headers_too_large; 376 } 377 header_block = realloc(fr->fr_header_block, fr->fr_header_block_sz); 378 if (!header_block) 379 { 380 LSQ_WARN("cannot allocate %u bytes for header block", 381 fr->fr_header_block_sz); 382 fr->fr_callbacks->frc_on_error(fr->fr_cb_ctx, stream_id, 383 FR_ERR_OTHER_ERROR); 384 return -1; 385 } 386 fr->fr_header_block = header_block; 387 fr->fr_state.by_type.headers_state.nread = 0; 388 fr->fr_state.reader_type = READER_CONTIN; 389 break; 390 case HTTP_FRAME_SETTINGS: 391 if (0 == fr->fr_state.payload_length || 392 0 != fr->fr_state.payload_length % 6) 393 { 394 LSQ_INFO("Framing error: %u is not a valid SETTINGS length", 395 fr->fr_state.payload_length); 396 fr->fr_callbacks->frc_on_error(fr->fr_cb_ctx, stream_id, 397 FR_ERR_INVALID_FRAME_SIZE); 398 return -1; 399 } 400 if (stream_id) 401 { /* RFC 7540, Section 6.5 */ 402 LSQ_INFO("Error: SETTINGS frame should not have stream ID set"); 403 fr->fr_callbacks->frc_on_error(fr->fr_cb_ctx, stream_id, 404 FR_ERR_NONZERO_STREAM_ID); 405 return -1; 406 } 407 fr->fr_state.by_type.settings_state.nread = 0; 408 fr->fr_state.reader_type = READER_SETTINGS; 409 break; 410 case HTTP_FRAME_PRIORITY: 411 if (fr->fr_state.payload_length != sizeof(struct http_prio_frame)) 412 { 413 LSQ_INFO("Framing error: %u is not a valid PRIORITY length", 414 fr->fr_state.payload_length); 415 fr->fr_callbacks->frc_on_error(fr->fr_cb_ctx, stream_id, 416 FR_ERR_INVALID_FRAME_SIZE); 417 return -1; 418 } 419 if (!stream_id) 420 { /* RFC 7540, Section 6.3 */ 421 LSQ_INFO("Error: PRIORITY frame must have stream ID set"); 422 fr->fr_callbacks->frc_on_error(fr->fr_cb_ctx, stream_id, 423 FR_ERR_ZERO_STREAM_ID); 424 return -1; 425 } 426 fr->fr_state.by_type.settings_state.nread = 0; 427 fr->fr_state.reader_type = READER_PRIORITY; 428 break; 429 headers_too_large: 430 LSQ_INFO("headers are too large (%u bytes), skipping", 431 fr->fr_state.payload_length); 432 fr->fr_callbacks->frc_on_error(fr->fr_cb_ctx, stream_id, 433 FR_ERR_BAD_HEADER); 434 /* fallthru */ 435 continue_skipping: 436 default: 437 fr->fr_state.by_type.skip_state.n_skipped = 0; 438 fr->fr_state.reader_type = READER_SKIP; 439 break; 440 } 441 442 fr->fr_flags |= FRF_HAVE_PREV; 443 fr->fr_prev_frame_type = fr->fr_state.header.hfh_type; 444 fr->fr_prev_hfh_flags = fr->fr_state.header.hfh_flags; 445 fr->fr_prev_stream_id = stream_id; 446 447 return 0; 448} 449 450 451static int 452read_http_frame_header (struct lsquic_frame_reader *fr) 453{ 454 ssize_t nr; 455 size_t ntoread; 456 unsigned char *dst; 457 458 ntoread = sizeof(fr->fr_state.header) - fr->fr_state.nh_read; 459 dst = (unsigned char *) &fr->fr_state.header + fr->fr_state.nh_read; 460 nr = fr->fr_read(fr->fr_stream, dst, ntoread); 461 if (nr <= 0) 462 RETURN_ERROR(nr); 463 fr->fr_state.nh_read += nr; 464 if (fr->fr_state.nh_read == sizeof(fr->fr_state.header)) 465 { 466 LSQ_DEBUG("read in frame %s", hft_to_string(fr->fr_state.header.hfh_type)); 467 return prepare_for_payload(fr); 468 } 469 else 470 return 0; 471} 472 473 474static int 475skip_payload (struct lsquic_frame_reader *fr) 476{ 477 struct skip_state *ss = &fr->fr_state.by_type.skip_state; 478 size_t ntoread = fr->fr_state.payload_length - ss->n_skipped; 479 unsigned char buf[0x100]; 480 if (ntoread > sizeof(buf)) 481 ntoread = sizeof(buf); 482 ssize_t nr = fr->fr_read(fr->fr_stream, buf, ntoread); 483 if (nr <= 0) 484 RETURN_ERROR(nr); 485 ss->n_skipped += nr; 486 if (ss->n_skipped == fr->fr_state.payload_length) 487 reset_state(fr); 488 return 0; 489} 490 491 492static int 493skip_headers_padding (struct lsquic_frame_reader *fr) 494{ 495 unsigned char buf[0x100]; 496 struct headers_state *hs = &fr->fr_state.by_type.headers_state; 497 unsigned pay_and_pad_length = fr->fr_state.payload_length - hs->pesw_size; 498 unsigned ntoread = pay_and_pad_length - hs->nread; 499 assert(ntoread <= sizeof(buf)); 500 if (ntoread > sizeof(buf)) 501 ntoread = sizeof(buf); 502 ssize_t nr = fr->fr_read(fr->fr_stream, buf, ntoread); 503 if (nr <= 0) 504 RETURN_ERROR(nr); 505 hs->nread += nr; 506 if (hs->nread == pay_and_pad_length) 507 reset_state(fr); 508 return 0; 509} 510 511 512static struct lsquic_stream * 513find_target_stream (const struct lsquic_frame_reader *fr) 514{ 515 lsquic_stream_id_t stream_id; 516 struct lsquic_conn *lconn; 517 518 stream_id = fr_get_stream_id(fr); 519 lconn = lsquic_stream_conn(fr->fr_stream); 520 if (lconn->cn_if->ci_get_stream_by_id) 521 return lconn->cn_if->ci_get_stream_by_id(lconn, stream_id); 522 523 return NULL; 524} 525 526 527static int 528decode_and_pass_payload (struct lsquic_frame_reader *fr) 529{ 530 struct headers_state *hs = &fr->fr_state.by_type.headers_state; 531 const unsigned char *comp, *end; 532 enum frame_reader_error err; 533 int s; 534 uint32_t stream_id32; 535 struct uncompressed_headers *uh = NULL; 536 void *hset = NULL; 537 struct lsxpack_header *hdr = NULL; 538 size_t req_space = 0; 539 lsquic_stream_t *target_stream = NULL; 540 541 if (!(fr->fr_flags & FRF_SERVER)) 542 target_stream = find_target_stream(fr); 543 hset = fr->fr_hsi_if->hsi_create_header_set(fr->fr_hsi_ctx, target_stream, 544 READER_PUSH_PROMISE == fr->fr_state.reader_type); 545 if (!hset) 546 { 547 err = FR_ERR_OTHER_ERROR; 548 goto stream_error; 549 } 550 551 comp = fr->fr_header_block; 552 end = comp + fr->fr_header_block_sz; 553 554 while (comp < end) 555 { 556 prepare: 557 hdr = fr->fr_hsi_if->hsi_prepare_decode(hset, hdr, req_space); 558 if (!hdr) 559 { 560 err = FR_ERR_OTHER_ERROR; 561 goto stream_error; 562 } 563 s = lshpack_dec_decode(fr->fr_hdec, &comp, end, hdr); 564 if (s == 0) 565 { 566 s = fr->fr_hsi_if->hsi_process_header(hset, hdr); 567 if (s == 0) 568 { 569#if LSQUIC_CONN_STATS 570 fr->fr_conn_stats->in.headers_uncomp += hdr->name_len + 571 hdr->val_len; 572#endif 573 req_space = 0; 574 hdr = NULL; 575 continue; 576 } 577 else if (s > 0) 578 err = FR_ERR_BAD_HEADER; 579 else 580 err = FR_ERR_OTHER_ERROR; 581 } 582 else if (s == LSHPACK_ERR_MORE_BUF) 583 { 584 req_space = hdr->val_len; 585 goto prepare; 586 } 587 else 588 err = FR_ERR_DECOMPRESS; 589 goto stream_error; 590 } 591 assert(comp == end); 592 593 s = fr->fr_hsi_if->hsi_process_header(hset, NULL); 594 if (s != 0) 595 { 596 err = s < 0 ? FR_ERR_OTHER_ERROR : FR_ERR_BAD_HEADER; 597 goto stream_error; 598 } 599 600 uh = calloc(1, sizeof(*uh)); 601 if (!uh) 602 { 603 err = FR_ERR_OTHER_ERROR; 604 goto stream_error; 605 } 606 607 memcpy(&stream_id32, fr->fr_state.header.hfh_stream_id, 608 sizeof(stream_id32)); 609 uh->uh_stream_id = ntohl(stream_id32); 610 uh->uh_oth_stream_id = hs->oth_stream_id; 611 if (HTTP_FRAME_HEADERS == fr->fr_state.by_type.headers_state.frame_type) 612 { 613 uh->uh_weight = hs->weight; 614 uh->uh_exclusive = hs->exclusive; 615 uh->uh_flags = 0; 616 } 617 else 618 { 619 assert(HTTP_FRAME_PUSH_PROMISE == 620 fr->fr_state.by_type.headers_state.frame_type); 621 uh->uh_weight = 0; /* Zero unused value */ 622 uh->uh_exclusive = 0; /* Zero unused value */ 623 uh->uh_flags = UH_PP; 624 } 625 if (fr->fr_state.header.hfh_flags & HFHF_END_STREAM) 626 uh->uh_flags |= UH_FIN; 627 if (fr->fr_hsi_if == lsquic_http1x_if) 628 uh->uh_flags |= UH_H1H; 629 uh->uh_hset = hset; 630 631 EV_LOG_HTTP_HEADERS_IN(LSQUIC_LOG_CONN_ID, fr->fr_flags & FRF_SERVER, uh); 632 if (HTTP_FRAME_HEADERS == fr->fr_state.by_type.headers_state.frame_type) 633 fr->fr_callbacks->frc_on_headers(fr->fr_cb_ctx, uh); 634 else 635 fr->fr_callbacks->frc_on_push_promise(fr->fr_cb_ctx, uh); 636#if LSQUIC_CONN_STATS 637 fr->fr_conn_stats->in.headers_comp += fr->fr_header_block_sz; 638#endif 639 640 return 0; 641 642 stream_error: 643 LSQ_INFO("%s: stream error %u", __func__, err); 644 if (hset) 645 fr->fr_hsi_if->hsi_discard_header_set(hset); 646 fr->fr_callbacks->frc_on_error(fr->fr_cb_ctx, fr_get_stream_id(fr), err); 647 return 0; 648} 649 650 651static int 652read_headers_block_fragment (struct lsquic_frame_reader *fr) 653{ 654 struct headers_state *hs = &fr->fr_state.by_type.headers_state; 655 ssize_t nr; 656 unsigned payload_length = fr->fr_state.payload_length - hs->pesw_size - 657 hs->pad_length; 658 if (!fr->fr_header_block) 659 { 660 fr->fr_header_block_sz = payload_length; 661 fr->fr_header_block = malloc(payload_length); 662 if (!fr->fr_header_block) 663 return -1; 664 } 665 nr = fr->fr_read(fr->fr_stream, fr->fr_header_block + hs->nread, 666 fr->fr_header_block_sz - hs->nread); 667 if (nr <= 0) 668 { 669 free(fr->fr_header_block); 670 fr->fr_header_block = NULL; 671 RETURN_ERROR(nr); 672 } 673 hs->nread += nr; 674 if (hs->nread == payload_length && 675 (fr->fr_state.header.hfh_flags & HFHF_END_HEADERS)) 676 { 677 int rv = decode_and_pass_payload(fr); 678 free(fr->fr_header_block); 679 fr->fr_header_block = NULL; 680 return rv; 681 } 682 else 683 return 0; 684} 685 686 687static int 688read_headers_block_fragment_and_padding (struct lsquic_frame_reader *fr) 689{ 690 struct headers_state *hs = &fr->fr_state.by_type.headers_state; 691 unsigned payload_length = fr->fr_state.payload_length - hs->pesw_size; 692 int rv; 693 if (hs->nread < payload_length - hs->pad_length) 694 rv = read_headers_block_fragment(fr); 695 else if (payload_length) 696 rv = skip_headers_padding(fr); 697 else 698 { /* Edge case where PESW takes up the whole frame */ 699 fr->fr_header_block_sz = 0; 700 fr->fr_header_block = NULL; 701 rv = 0; 702 } 703 if (0 == rv && hs->nread == payload_length) 704 reset_state(fr); 705 return rv; 706} 707 708 709static int 710read_headers_pesw (struct lsquic_frame_reader *fr) 711{ 712 struct headers_state *hs = &fr->fr_state.by_type.headers_state; 713 ssize_t nr = fr->fr_read(fr->fr_stream, hs->pesw + hs->pesw_nread, 714 hs->pesw_size - hs->pesw_nread); 715 if (nr <= 0) 716 RETURN_ERROR(nr); 717 hs->pesw_nread += nr; 718 if (hs->pesw_nread == hs->pesw_size) 719 { 720 unsigned char *p = hs->pesw; 721 if (fr->fr_state.header.hfh_flags & HFHF_PADDED) 722 hs->pad_length = *p++; 723 if (fr->fr_state.header.hfh_flags & HFHF_PRIORITY) 724 { 725 hs->exclusive = p[0] >> 7; 726 p[0] &= ~0x80; /* Note that we are modifying pesw buffer. */ 727 memcpy(&hs->oth_stream_id, p, sizeof(hs->oth_stream_id)); 728 hs->oth_stream_id = ntohl(hs->oth_stream_id); 729 p += 4; 730 hs->weight = 1 + *p++; 731 } 732 assert(p - hs->pesw == hs->pesw_size); 733 734 if (hs->pesw_size + hs->pad_length > fr->fr_state.payload_length) 735 { 736 LSQ_INFO("Invalid headers frame: pesw length and padding length " 737 "are larger than the payload length"); 738 errno = EBADMSG; 739 return -1; 740 } 741 } 742 return 0; 743} 744 745 746static int 747read_headers (struct lsquic_frame_reader *fr) 748{ 749 struct headers_state *hs = &fr->fr_state.by_type.headers_state; 750 if (hs->pesw_nread < hs->pesw_size) 751 return read_headers_pesw(fr); 752 else 753 return read_headers_block_fragment_and_padding(fr); 754} 755 756 757static int 758read_push_promise_pesw (struct lsquic_frame_reader *fr) 759{ 760 struct headers_state *hs = &fr->fr_state.by_type.headers_state; 761 ssize_t nr = fr->fr_read(fr->fr_stream, hs->pesw + hs->pesw_nread, 762 hs->pesw_size - hs->pesw_nread); 763 if (nr <= 0) 764 RETURN_ERROR(nr); 765 hs->pesw_nread += nr; 766 if (hs->pesw_nread == hs->pesw_size) 767 { 768 unsigned char *p = hs->pesw; 769 if (fr->fr_state.header.hfh_flags & HFHF_PADDED) 770 hs->pad_length = *p++; 771 p[0] &= ~0x80; /* Clear reserved bit. Note: modifying pesw buffer. */ 772 memcpy(&hs->oth_stream_id, p, sizeof(hs->oth_stream_id)); 773 hs->oth_stream_id = ntohl(hs->oth_stream_id); 774 p += 4; 775 assert(p - hs->pesw == hs->pesw_size); 776 if (hs->pesw_size + hs->pad_length > fr->fr_state.payload_length) 777 { 778 LSQ_INFO("Invalid PUSH_PROMISE frame: pesw length and padding length " 779 "are larger than the payload length"); 780 errno = EBADMSG; 781 return -1; 782 } 783 } 784 return 0; 785} 786 787 788static int 789read_push_promise (struct lsquic_frame_reader *fr) 790{ 791 struct headers_state *hs = &fr->fr_state.by_type.headers_state; 792 if (hs->pesw_nread < hs->pesw_size) 793 return read_push_promise_pesw(fr); 794 else 795 return read_headers_block_fragment_and_padding(fr); 796} 797 798 799static int 800read_contin (struct lsquic_frame_reader *fr) 801{ 802 struct headers_state *hs = &fr->fr_state.by_type.headers_state; 803 unsigned ntoread; 804 ssize_t nr; 805 806 ntoread = fr->fr_state.payload_length - hs->nread; 807 nr = fr->fr_read(fr->fr_stream, 808 fr->fr_header_block + fr->fr_header_block_sz - ntoread, 809 ntoread); 810 if (nr <= 0) 811 RETURN_ERROR(nr); 812 hs->nread += nr; 813 if (hs->nread == fr->fr_state.payload_length) 814 { 815 if (fr->fr_state.header.hfh_flags & HFHF_END_HEADERS) 816 { 817 int rv = decode_and_pass_payload(fr); 818 free(fr->fr_header_block); 819 fr->fr_header_block = NULL; 820 reset_state(fr); 821 return rv; 822 } 823 else 824 { 825 reset_state(fr); 826 return 0; 827 } 828 } 829 else 830 return 0; 831} 832 833 834static int 835read_settings (struct lsquic_frame_reader *fr) 836{ 837 struct settings_state *ss = &fr->fr_state.by_type.settings_state; 838 unsigned ntoread; 839 ssize_t nr; 840 uint32_t setting_value; 841 uint16_t setting_id; 842 843 ntoread = sizeof(ss->set_buf) - ss->nread; 844 nr = fr->fr_read(fr->fr_stream, ss->set_buf + ss->nread, ntoread); 845 if (nr <= 0) 846 RETURN_ERROR(nr); 847 ss->nread += nr; 848 if (ss->nread == sizeof(ss->set_buf)) 849 { 850 memcpy(&setting_id, ss->set_buf, 2); 851 memcpy(&setting_value, ss->set_buf + 2, 4); 852 setting_id = ntohs(setting_id); 853 setting_value = ntohl(setting_value); 854 EV_LOG_CONN_EVENT(LSQUIC_LOG_CONN_ID, "read HTTP SETTING %s=%"PRIu32, 855 lsquic_http_setting_id2str(setting_id), setting_value); 856 fr->fr_callbacks->frc_on_settings(fr->fr_cb_ctx, setting_id, 857 setting_value); 858 859 fr->fr_state.payload_length -= sizeof(ss->set_buf); 860 if (0 == fr->fr_state.payload_length) 861 reset_state(fr); 862 else 863 ss->nread = 0; 864 } 865 return 0; 866} 867 868 869static int 870read_priority (struct lsquic_frame_reader *fr) 871{ 872 struct priority_state *ps = &fr->fr_state.by_type.priority_state; 873 unsigned ntoread; 874 ssize_t nr; 875 uint32_t stream_id, dep_stream_id; 876 int exclusive; 877 878 ntoread = sizeof(ps->u.prio_buf) - ps->nread; 879 nr = fr->fr_read(fr->fr_stream, ps->u.prio_buf + ps->nread, ntoread); 880 if (nr <= 0) 881 RETURN_ERROR(nr); 882 ps->nread += nr; 883 if (ps->nread == sizeof(ps->u.prio_buf)) 884 { 885 memcpy(&dep_stream_id, ps->u.prio_frame.hpf_stream_id, 4); 886 dep_stream_id = ntohl(dep_stream_id); 887 exclusive = dep_stream_id >> 31; 888 dep_stream_id &= ~(1UL << 31); 889 stream_id = fr_get_stream_id(fr); 890 if (stream_id == dep_stream_id) 891 fr->fr_callbacks->frc_on_error(fr->fr_cb_ctx, stream_id, 892 FR_ERR_SELF_DEP_STREAM); 893 else 894 { 895 EV_LOG_CONN_EVENT(LSQUIC_LOG_CONN_ID, "read PRIORITY frame; " 896 "stream: %"PRIu32", dep stream %"PRIu32", exclusive: %d, " 897 "weight: %u", stream_id, dep_stream_id, exclusive, 898 ps->u.prio_frame.hpf_weight + 1); 899 fr->fr_callbacks->frc_on_priority(fr->fr_cb_ctx, stream_id, 900 exclusive, dep_stream_id, ps->u.prio_frame.hpf_weight + 1); 901 } 902 reset_state(fr); 903 } 904 return 0; 905} 906 907 908static int 909read_payload (struct lsquic_frame_reader *fr) 910{ 911 switch (fr->fr_state.reader_type) 912 { 913 case READER_HEADERS: 914 return read_headers(fr); 915 case READER_PUSH_PROMISE: 916 return read_push_promise(fr); 917 case READER_CONTIN: 918 return read_contin(fr); 919 case READER_SETTINGS: 920 return read_settings(fr); 921 case READER_PRIORITY: 922 return read_priority(fr); 923 default: 924 assert(READER_SKIP == fr->fr_state.reader_type); 925 return skip_payload(fr); 926 } 927} 928 929 930int 931lsquic_frame_reader_read (struct lsquic_frame_reader *fr) 932{ 933 if (fr->fr_state.nh_read < sizeof(fr->fr_state.header)) 934 return read_http_frame_header(fr); 935 else 936 return read_payload(fr); 937} 938 939 940size_t 941lsquic_frame_reader_mem_used (const struct lsquic_frame_reader *fr) 942{ 943 size_t size; 944 size = sizeof(*fr); 945 if (fr->fr_header_block) 946 size += fr->fr_header_block_sz; 947 return size; 948} 949