lsquic_frame_reader.c revision 992bbcdb
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 int 513decode_and_pass_payload (struct lsquic_frame_reader *fr) 514{ 515 struct headers_state *hs = &fr->fr_state.by_type.headers_state; 516 const unsigned char *comp, *end; 517 enum frame_reader_error err; 518 int s; 519 uint32_t stream_id32; 520 struct uncompressed_headers *uh = NULL; 521 void *hset = NULL; 522 struct lsxpack_header *hdr = NULL; 523 size_t req_space = 0; 524 525 hset = fr->fr_hsi_if->hsi_create_header_set(fr->fr_hsi_ctx, 526 READER_PUSH_PROMISE == fr->fr_state.reader_type); 527 if (!hset) 528 { 529 err = FR_ERR_OTHER_ERROR; 530 goto stream_error; 531 } 532 533 comp = fr->fr_header_block; 534 end = comp + fr->fr_header_block_sz; 535 536 while (comp < end) 537 { 538 prepare: 539 hdr = fr->fr_hsi_if->hsi_prepare_decode(hset, hdr, req_space); 540 if (!hdr) 541 { 542 err = FR_ERR_OTHER_ERROR; 543 goto stream_error; 544 } 545 s = lshpack_dec_decode(fr->fr_hdec, &comp, end, hdr); 546 if (s == 0) 547 { 548 s = fr->fr_hsi_if->hsi_process_header(hset, hdr); 549 if (s == 0) 550 { 551#if LSQUIC_CONN_STATS 552 fr->fr_conn_stats->in.headers_uncomp += hdr->name_len + 553 hdr->val_len; 554#endif 555 req_space = 0; 556 hdr = NULL; 557 continue; 558 } 559 else if (s > 0) 560 err = FR_ERR_BAD_HEADER; 561 else 562 err = FR_ERR_OTHER_ERROR; 563 } 564 else if (s == LSHPACK_ERR_MORE_BUF) 565 { 566 req_space = hdr->val_len; 567 goto prepare; 568 } 569 else 570 err = FR_ERR_DECOMPRESS; 571 goto stream_error; 572 } 573 assert(comp == end); 574 575 s = fr->fr_hsi_if->hsi_process_header(hset, NULL); 576 if (s != 0) 577 { 578 err = s < 0 ? FR_ERR_OTHER_ERROR : FR_ERR_BAD_HEADER; 579 goto stream_error; 580 } 581 582 uh = calloc(1, sizeof(*uh)); 583 if (!uh) 584 { 585 err = FR_ERR_OTHER_ERROR; 586 goto stream_error; 587 } 588 589 memcpy(&stream_id32, fr->fr_state.header.hfh_stream_id, 590 sizeof(stream_id32)); 591 uh->uh_stream_id = ntohl(stream_id32); 592 uh->uh_oth_stream_id = hs->oth_stream_id; 593 if (HTTP_FRAME_HEADERS == fr->fr_state.by_type.headers_state.frame_type) 594 { 595 uh->uh_weight = hs->weight; 596 uh->uh_exclusive = hs->exclusive; 597 uh->uh_flags = 0; 598 } 599 else 600 { 601 assert(HTTP_FRAME_PUSH_PROMISE == 602 fr->fr_state.by_type.headers_state.frame_type); 603 uh->uh_weight = 0; /* Zero unused value */ 604 uh->uh_exclusive = 0; /* Zero unused value */ 605 uh->uh_flags = UH_PP; 606 } 607 if (fr->fr_state.header.hfh_flags & HFHF_END_STREAM) 608 uh->uh_flags |= UH_FIN; 609 if (fr->fr_hsi_if == lsquic_http1x_if) 610 uh->uh_flags |= UH_H1H; 611 uh->uh_hset = hset; 612 613 EV_LOG_HTTP_HEADERS_IN(LSQUIC_LOG_CONN_ID, fr->fr_flags & FRF_SERVER, uh); 614 if (HTTP_FRAME_HEADERS == fr->fr_state.by_type.headers_state.frame_type) 615 fr->fr_callbacks->frc_on_headers(fr->fr_cb_ctx, uh); 616 else 617 fr->fr_callbacks->frc_on_push_promise(fr->fr_cb_ctx, uh); 618#if LSQUIC_CONN_STATS 619 fr->fr_conn_stats->in.headers_comp += fr->fr_header_block_sz; 620#endif 621 622 return 0; 623 624 stream_error: 625 LSQ_INFO("%s: stream error %u", __func__, err); 626 if (hset) 627 fr->fr_hsi_if->hsi_discard_header_set(hset); 628 fr->fr_callbacks->frc_on_error(fr->fr_cb_ctx, fr_get_stream_id(fr), err); 629 return 0; 630} 631 632 633static int 634read_headers_block_fragment (struct lsquic_frame_reader *fr) 635{ 636 struct headers_state *hs = &fr->fr_state.by_type.headers_state; 637 ssize_t nr; 638 unsigned payload_length = fr->fr_state.payload_length - hs->pesw_size - 639 hs->pad_length; 640 if (!fr->fr_header_block) 641 { 642 fr->fr_header_block_sz = payload_length; 643 fr->fr_header_block = malloc(payload_length); 644 if (!fr->fr_header_block) 645 return -1; 646 } 647 nr = fr->fr_read(fr->fr_stream, fr->fr_header_block + hs->nread, 648 fr->fr_header_block_sz - hs->nread); 649 if (nr <= 0) 650 { 651 free(fr->fr_header_block); 652 fr->fr_header_block = NULL; 653 RETURN_ERROR(nr); 654 } 655 hs->nread += nr; 656 if (hs->nread == payload_length && 657 (fr->fr_state.header.hfh_flags & HFHF_END_HEADERS)) 658 { 659 int rv = decode_and_pass_payload(fr); 660 free(fr->fr_header_block); 661 fr->fr_header_block = NULL; 662 return rv; 663 } 664 else 665 return 0; 666} 667 668 669static int 670read_headers_block_fragment_and_padding (struct lsquic_frame_reader *fr) 671{ 672 struct headers_state *hs = &fr->fr_state.by_type.headers_state; 673 unsigned payload_length = fr->fr_state.payload_length - hs->pesw_size; 674 int rv; 675 if (hs->nread < payload_length - hs->pad_length) 676 rv = read_headers_block_fragment(fr); 677 else if (payload_length) 678 rv = skip_headers_padding(fr); 679 else 680 { /* Edge case where PESW takes up the whole frame */ 681 fr->fr_header_block_sz = 0; 682 fr->fr_header_block = NULL; 683 rv = 0; 684 } 685 if (0 == rv && hs->nread == payload_length) 686 reset_state(fr); 687 return rv; 688} 689 690 691static int 692read_headers_pesw (struct lsquic_frame_reader *fr) 693{ 694 struct headers_state *hs = &fr->fr_state.by_type.headers_state; 695 ssize_t nr = fr->fr_read(fr->fr_stream, hs->pesw + hs->pesw_nread, 696 hs->pesw_size - hs->pesw_nread); 697 if (nr <= 0) 698 RETURN_ERROR(nr); 699 hs->pesw_nread += nr; 700 if (hs->pesw_nread == hs->pesw_size) 701 { 702 unsigned char *p = hs->pesw; 703 if (fr->fr_state.header.hfh_flags & HFHF_PADDED) 704 hs->pad_length = *p++; 705 if (fr->fr_state.header.hfh_flags & HFHF_PRIORITY) 706 { 707 hs->exclusive = p[0] >> 7; 708 p[0] &= ~0x80; /* Note that we are modifying pesw buffer. */ 709 memcpy(&hs->oth_stream_id, p, sizeof(hs->oth_stream_id)); 710 hs->oth_stream_id = ntohl(hs->oth_stream_id); 711 p += 4; 712 hs->weight = 1 + *p++; 713 } 714 assert(p - hs->pesw == hs->pesw_size); 715 716 if (hs->pesw_size + hs->pad_length > fr->fr_state.payload_length) 717 { 718 LSQ_INFO("Invalid headers frame: pesw length and padding length " 719 "are larger than the payload length"); 720 errno = EBADMSG; 721 return -1; 722 } 723 } 724 return 0; 725} 726 727 728static int 729read_headers (struct lsquic_frame_reader *fr) 730{ 731 struct headers_state *hs = &fr->fr_state.by_type.headers_state; 732 if (hs->pesw_nread < hs->pesw_size) 733 return read_headers_pesw(fr); 734 else 735 return read_headers_block_fragment_and_padding(fr); 736} 737 738 739static int 740read_push_promise_pesw (struct lsquic_frame_reader *fr) 741{ 742 struct headers_state *hs = &fr->fr_state.by_type.headers_state; 743 ssize_t nr = fr->fr_read(fr->fr_stream, hs->pesw + hs->pesw_nread, 744 hs->pesw_size - hs->pesw_nread); 745 if (nr <= 0) 746 RETURN_ERROR(nr); 747 hs->pesw_nread += nr; 748 if (hs->pesw_nread == hs->pesw_size) 749 { 750 unsigned char *p = hs->pesw; 751 if (fr->fr_state.header.hfh_flags & HFHF_PADDED) 752 hs->pad_length = *p++; 753 p[0] &= ~0x80; /* Clear reserved bit. Note: modifying pesw buffer. */ 754 memcpy(&hs->oth_stream_id, p, sizeof(hs->oth_stream_id)); 755 hs->oth_stream_id = ntohl(hs->oth_stream_id); 756 p += 4; 757 assert(p - hs->pesw == hs->pesw_size); 758 if (hs->pesw_size + hs->pad_length > fr->fr_state.payload_length) 759 { 760 LSQ_INFO("Invalid PUSH_PROMISE frame: pesw length and padding length " 761 "are larger than the payload length"); 762 errno = EBADMSG; 763 return -1; 764 } 765 } 766 return 0; 767} 768 769 770static int 771read_push_promise (struct lsquic_frame_reader *fr) 772{ 773 struct headers_state *hs = &fr->fr_state.by_type.headers_state; 774 if (hs->pesw_nread < hs->pesw_size) 775 return read_push_promise_pesw(fr); 776 else 777 return read_headers_block_fragment_and_padding(fr); 778} 779 780 781static int 782read_contin (struct lsquic_frame_reader *fr) 783{ 784 struct headers_state *hs = &fr->fr_state.by_type.headers_state; 785 unsigned ntoread; 786 ssize_t nr; 787 788 ntoread = fr->fr_state.payload_length - hs->nread; 789 nr = fr->fr_read(fr->fr_stream, 790 fr->fr_header_block + fr->fr_header_block_sz - ntoread, 791 ntoread); 792 if (nr <= 0) 793 RETURN_ERROR(nr); 794 hs->nread += nr; 795 if (hs->nread == fr->fr_state.payload_length) 796 { 797 if (fr->fr_state.header.hfh_flags & HFHF_END_HEADERS) 798 { 799 int rv = decode_and_pass_payload(fr); 800 free(fr->fr_header_block); 801 fr->fr_header_block = NULL; 802 reset_state(fr); 803 return rv; 804 } 805 else 806 { 807 reset_state(fr); 808 return 0; 809 } 810 } 811 else 812 return 0; 813} 814 815 816static int 817read_settings (struct lsquic_frame_reader *fr) 818{ 819 struct settings_state *ss = &fr->fr_state.by_type.settings_state; 820 unsigned ntoread; 821 ssize_t nr; 822 uint32_t setting_value; 823 uint16_t setting_id; 824 825 ntoread = sizeof(ss->set_buf) - ss->nread; 826 nr = fr->fr_read(fr->fr_stream, ss->set_buf + ss->nread, ntoread); 827 if (nr <= 0) 828 RETURN_ERROR(nr); 829 ss->nread += nr; 830 if (ss->nread == sizeof(ss->set_buf)) 831 { 832 memcpy(&setting_id, ss->set_buf, 2); 833 memcpy(&setting_value, ss->set_buf + 2, 4); 834 setting_id = ntohs(setting_id); 835 setting_value = ntohl(setting_value); 836 EV_LOG_CONN_EVENT(LSQUIC_LOG_CONN_ID, "read HTTP SETTING %s=%"PRIu32, 837 lsquic_http_setting_id2str(setting_id), setting_value); 838 fr->fr_callbacks->frc_on_settings(fr->fr_cb_ctx, setting_id, 839 setting_value); 840 841 fr->fr_state.payload_length -= sizeof(ss->set_buf); 842 if (0 == fr->fr_state.payload_length) 843 reset_state(fr); 844 else 845 ss->nread = 0; 846 } 847 return 0; 848} 849 850 851static int 852read_priority (struct lsquic_frame_reader *fr) 853{ 854 struct priority_state *ps = &fr->fr_state.by_type.priority_state; 855 unsigned ntoread; 856 ssize_t nr; 857 uint32_t stream_id, dep_stream_id; 858 int exclusive; 859 860 ntoread = sizeof(ps->u.prio_buf) - ps->nread; 861 nr = fr->fr_read(fr->fr_stream, ps->u.prio_buf + ps->nread, ntoread); 862 if (nr <= 0) 863 RETURN_ERROR(nr); 864 ps->nread += nr; 865 if (ps->nread == sizeof(ps->u.prio_buf)) 866 { 867 memcpy(&dep_stream_id, ps->u.prio_frame.hpf_stream_id, 4); 868 dep_stream_id = ntohl(dep_stream_id); 869 exclusive = dep_stream_id >> 31; 870 dep_stream_id &= ~(1UL << 31); 871 stream_id = fr_get_stream_id(fr); 872 if (stream_id == dep_stream_id) 873 fr->fr_callbacks->frc_on_error(fr->fr_cb_ctx, stream_id, 874 FR_ERR_SELF_DEP_STREAM); 875 else 876 { 877 EV_LOG_CONN_EVENT(LSQUIC_LOG_CONN_ID, "read PRIORITY frame; " 878 "stream: %"PRIu32", dep stream %"PRIu32", exclusive: %d, " 879 "weight: %u", stream_id, dep_stream_id, exclusive, 880 ps->u.prio_frame.hpf_weight + 1); 881 fr->fr_callbacks->frc_on_priority(fr->fr_cb_ctx, stream_id, 882 exclusive, dep_stream_id, ps->u.prio_frame.hpf_weight + 1); 883 } 884 reset_state(fr); 885 } 886 return 0; 887} 888 889 890static int 891read_payload (struct lsquic_frame_reader *fr) 892{ 893 switch (fr->fr_state.reader_type) 894 { 895 case READER_HEADERS: 896 return read_headers(fr); 897 case READER_PUSH_PROMISE: 898 return read_push_promise(fr); 899 case READER_CONTIN: 900 return read_contin(fr); 901 case READER_SETTINGS: 902 return read_settings(fr); 903 case READER_PRIORITY: 904 return read_priority(fr); 905 default: 906 assert(READER_SKIP == fr->fr_state.reader_type); 907 return skip_payload(fr); 908 } 909} 910 911 912int 913lsquic_frame_reader_read (struct lsquic_frame_reader *fr) 914{ 915 if (fr->fr_state.nh_read < sizeof(fr->fr_state.header)) 916 return read_http_frame_header(fr); 917 else 918 return read_payload(fr); 919} 920 921 922size_t 923lsquic_frame_reader_mem_used (const struct lsquic_frame_reader *fr) 924{ 925 size_t size; 926 size = sizeof(*fr); 927 if (fr->fr_header_block) 928 size += fr->fr_header_block_sz; 929 return size; 930} 931