lsquic_qdec_hdl.c revision 8dc2321b
1/* Copyright (c) 2017 - 2020 LiteSpeed Technologies Inc. See LICENSE. */ 2/* 3 * lsquic_qdec_hdl.c -- QPACK decoder streams handler 4 */ 5 6#include <assert.h> 7#include <errno.h> 8#include <inttypes.h> 9#include <stdlib.h> 10#include <string.h> 11#include <sys/queue.h> 12 13#include "lsquic.h" 14#include "lsquic_types.h" 15#include "lsxpack_header.h" 16#include "lsquic_int_types.h" 17#include "lsquic_sfcw.h" 18#include "lsquic_varint.h" 19#include "lsquic_hq.h" 20#include "lsquic_hash.h" 21#include "lsquic_stream.h" 22#include "lsquic_frab_list.h" 23#include "lsqpack.h" 24#include "lsquic_http1x_if.h" 25#include "lsquic_qdec_hdl.h" 26#include "lsquic_mm.h" 27#include "lsquic_engine_public.h" 28#include "lsquic_headers.h" 29#include "lsquic_conn.h" 30 31#define LSQUIC_LOGGER_MODULE LSQLM_QDEC_HDL 32#define LSQUIC_LOG_CONN_ID lsquic_conn_log_cid(qdh->qdh_conn) 33#include "lsquic_logger.h" 34 35static const struct lsqpack_dec_hset_if dhi_if; 36 37 38struct header_ctx 39{ 40 void *hset; 41 struct qpack_dec_hdl *qdh; 42}; 43 44 45/* We need to allocate struct uncompressed_headers anyway when header set 46 * is complete and we give it to the stream using lsquic_stream_uh_in(). 47 * To save a malloc, we reuse context after we're done with it. 48 */ 49union hblock_ctx 50{ 51 struct header_ctx ctx; 52 struct uncompressed_headers uh; 53}; 54 55 56static int 57qdh_write_decoder (struct qpack_dec_hdl *qdh, const unsigned char *buf, 58 size_t sz) 59{ 60 ssize_t nw; 61 62 if (!(qdh->qdh_dec_sm_out && lsquic_frab_list_empty(&qdh->qdh_fral))) 63 { 64 write_to_frab: 65 if (0 == lsquic_frab_list_write(&qdh->qdh_fral, 66 (unsigned char *) buf, sz)) 67 { 68 LSQ_DEBUG("wrote %zu bytes to frab list", sz); 69 lsquic_stream_wantwrite(qdh->qdh_dec_sm_out, 1); 70 return 0; 71 } 72 else 73 { 74 LSQ_INFO("error writing to frab list"); 75 return -1; 76 } 77 } 78 79 nw = lsquic_stream_write(qdh->qdh_dec_sm_out, buf, sz); 80 if (nw < 0) 81 { 82 LSQ_INFO("error writing to outgoing QPACK decoder stream: %s", 83 strerror(errno)); 84 return -1; 85 } 86 LSQ_DEBUG("wrote %zd bytes to outgoing QPACK decoder stream", nw); 87 88 if ((size_t) nw == sz) 89 return 0; 90 91 buf = buf + nw; 92 sz -= (size_t) nw; 93 goto write_to_frab; 94} 95 96 97static int 98qdh_write_type (struct qpack_dec_hdl *qdh) 99{ 100 int s; 101 102#ifndef NDEBUG 103 const char *env = getenv("LSQUIC_RND_VARINT_LEN"); 104 if (env && atoi(env)) 105 { 106 s = rand() & 3; 107 LSQ_DEBUG("writing %d-byte stream type", 1 << s); 108 } 109 else 110#endif 111 s = 0; 112 113 switch (s) 114 { 115 case 0: 116 return qdh_write_decoder(qdh, 117 (unsigned char []) { HQUST_QPACK_DEC }, 1); 118 case 1: 119 return qdh_write_decoder(qdh, 120 (unsigned char []) { 0x40, HQUST_QPACK_DEC }, 2); 121 case 2: 122 return qdh_write_decoder(qdh, 123 (unsigned char []) { 0x80, 0x00, 0x00, HQUST_QPACK_DEC }, 4); 124 default: 125 return qdh_write_decoder(qdh, 126 (unsigned char []) { 0xC0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 127 HQUST_QPACK_DEC }, 8); 128 } 129} 130 131 132static void 133qdh_begin_out (struct qpack_dec_hdl *qdh) 134{ 135 if (0 != qdh_write_type(qdh)) 136 { 137 LSQ_WARN("%s: could not write to decoder", __func__); 138 qdh->qdh_conn->cn_if->ci_internal_error(qdh->qdh_conn, 139 "cannot write to decoder stream"); 140 } 141} 142 143 144int 145lsquic_qdh_init (struct qpack_dec_hdl *qdh, struct lsquic_conn *conn, 146 int is_server, const struct lsquic_engine_public *enpub, 147 unsigned dyn_table_size, unsigned max_risked_streams) 148{ 149 enum lsqpack_dec_opts dec_opts; 150 151 dec_opts = 0; 152 if (enpub->enp_hsi_if->hsi_flags & LSQUIC_HSI_HTTP1X) 153 dec_opts |= LSQPACK_DEC_OPT_HTTP1X; 154 if (enpub->enp_hsi_if->hsi_flags & LSQUIC_HSI_HASH_NAME) 155 dec_opts |= LSQPACK_DEC_OPT_HASH_NAME; 156 if (enpub->enp_hsi_if->hsi_flags & LSQUIC_HSI_HASH_NAMEVAL) 157 dec_opts |= LSQPACK_DEC_OPT_HASH_NAMEVAL; 158 159 qdh->qdh_conn = conn; 160 lsquic_frab_list_init(&qdh->qdh_fral, 0x400, NULL, NULL, NULL); 161 lsqpack_dec_init(&qdh->qdh_decoder, (void *) conn, dyn_table_size, 162 max_risked_streams, &dhi_if, dec_opts); 163 qdh->qdh_flags |= QDH_INITIALIZED; 164 qdh->qdh_enpub = enpub; 165 if (qdh->qdh_enpub->enp_hsi_if == lsquic_http1x_if) 166 { 167 qdh->qdh_h1x_ctor_ctx = (struct http1x_ctor_ctx) { 168 .conn = conn, 169 .max_headers_sz = MAX_HTTP1X_HEADERS_SIZE, 170 .is_server = is_server, 171 }; 172 qdh->qdh_hsi_ctx = &qdh->qdh_h1x_ctor_ctx; 173 } 174 else 175 qdh->qdh_hsi_ctx = qdh->qdh_enpub->enp_hsi_ctx; 176 if (qdh->qdh_dec_sm_out) 177 qdh_begin_out(qdh); 178 if (qdh->qdh_enc_sm_in) 179 lsquic_stream_wantread(qdh->qdh_enc_sm_in, 1); 180 LSQ_DEBUG("initialized"); 181 return 0; 182} 183 184 185void 186lsquic_qdh_cleanup (struct qpack_dec_hdl *qdh) 187{ 188 if (qdh->qdh_flags & QDH_INITIALIZED) 189 { 190 LSQ_DEBUG("cleanup"); 191 lsqpack_dec_cleanup(&qdh->qdh_decoder); 192 lsquic_frab_list_cleanup(&qdh->qdh_fral); 193 qdh->qdh_flags &= ~QDH_INITIALIZED; 194 } 195} 196 197static lsquic_stream_ctx_t * 198qdh_out_on_new (void *stream_if_ctx, struct lsquic_stream *stream) 199{ 200 struct qpack_dec_hdl *const qdh = stream_if_ctx; 201 qdh->qdh_dec_sm_out = stream; 202 if (qdh->qdh_flags & QDH_INITIALIZED) 203 qdh_begin_out(qdh); 204 LSQ_DEBUG("initialized outgoing decoder stream"); 205 return (void *) qdh; 206} 207 208 209static void 210qdh_out_on_write (struct lsquic_stream *stream, lsquic_stream_ctx_t *ctx) 211{ 212 struct qpack_dec_hdl *const qdh = (void *) ctx; 213 struct lsquic_reader reader; 214 ssize_t nw; 215 unsigned char buf[LSQPACK_LONGEST_ICI]; 216 217 if (lsqpack_dec_ici_pending(&qdh->qdh_decoder)) 218 { 219 nw = lsqpack_dec_write_ici(&qdh->qdh_decoder, buf, sizeof(buf)); 220 if (nw > 0) 221 { 222 if (0 == qdh_write_decoder(qdh, buf, nw)) 223 LSQ_DEBUG("wrote %zd-byte TSS instruction", nw); 224 else 225 goto err; 226 } 227 else if (nw < 0) 228 { 229 LSQ_WARN("could not generate TSS instruction"); 230 goto err; 231 } 232 } 233 234 if (lsquic_frab_list_empty(&qdh->qdh_fral)) 235 { 236 LSQ_DEBUG("%s: nothing to write", __func__); 237 lsquic_stream_wantwrite(stream, 0); 238 return; 239 } 240 241 reader = (struct lsquic_reader) { 242 .lsqr_read = lsquic_frab_list_read, 243 .lsqr_size = lsquic_frab_list_size, 244 .lsqr_ctx = &qdh->qdh_fral, 245 }; 246 247 nw = lsquic_stream_writef(stream, &reader); 248 if (nw >= 0) 249 { 250 LSQ_DEBUG("wrote %zd bytes to stream", nw); 251 (void) lsquic_stream_flush(stream); 252 if (lsquic_frab_list_empty(&qdh->qdh_fral)) 253 { 254 lsquic_stream_wantwrite(stream, 0); 255 if (qdh->qdh_on_dec_sent_func) 256 { 257 LSQ_DEBUG("buffered data written: call callback"); 258 qdh->qdh_on_dec_sent_func(qdh->qdh_on_dec_sent_ctx); 259 qdh->qdh_on_dec_sent_func = NULL; 260 qdh->qdh_on_dec_sent_ctx = NULL; 261 } 262 } 263 } 264 else 265 { 266 LSQ_WARN("cannot write to stream: %s", strerror(errno)); 267 err: 268 lsquic_stream_wantwrite(stream, 0); 269 qdh->qdh_conn->cn_if->ci_internal_error(qdh->qdh_conn, 270 "cannot write to stream"); 271 } 272} 273 274 275static void 276qdh_out_on_close (struct lsquic_stream *stream, lsquic_stream_ctx_t *ctx) 277{ 278 struct qpack_dec_hdl *const qdh = (void *) ctx; 279 qdh->qdh_dec_sm_out = NULL; 280 LSQ_DEBUG("closed outgoing decoder stream"); 281} 282 283 284static void 285qdh_out_on_read (struct lsquic_stream *stream, lsquic_stream_ctx_t *ctx) 286{ 287 assert(0); 288} 289 290 291static const struct lsquic_stream_if qdh_dec_sm_out_if = 292{ 293 .on_new_stream = qdh_out_on_new, 294 .on_read = qdh_out_on_read, 295 .on_write = qdh_out_on_write, 296 .on_close = qdh_out_on_close, 297}; 298const struct lsquic_stream_if *const lsquic_qdh_dec_sm_out_if = 299 &qdh_dec_sm_out_if; 300 301 302static lsquic_stream_ctx_t * 303qdh_in_on_new (void *stream_if_ctx, struct lsquic_stream *stream) 304{ 305 struct qpack_dec_hdl *const qdh = stream_if_ctx; 306 qdh->qdh_enc_sm_in = stream; 307 if (qdh->qdh_flags & QDH_INITIALIZED) 308 lsquic_stream_wantread(qdh->qdh_enc_sm_in, 1); 309 LSQ_DEBUG("initialized incoming encoder stream"); 310 return (void *) qdh; 311} 312 313 314static size_t 315qdh_read_encoder_stream (void *ctx, const unsigned char *buf, size_t sz, 316 int fin) 317{ 318 struct qpack_dec_hdl *const qdh = (void *) ctx; 319 const struct lsqpack_dec_err *qerr; 320 int s; 321 322 if (fin) 323 { 324 LSQ_INFO("encoder stream is closed"); 325 qdh->qdh_conn->cn_if->ci_abort_error(qdh->qdh_conn, 1, 326 HEC_CLOSED_CRITICAL_STREAM, "Peer closed QPACK encoder stream"); 327 goto end; 328 } 329 330 s = lsqpack_dec_enc_in(&qdh->qdh_decoder, buf, sz); 331 if (s != 0) 332 { 333 LSQ_INFO("error reading encoder stream"); 334 qerr = lsqpack_dec_get_err_info(&qdh->qdh_decoder); 335 qdh->qdh_conn->cn_if->ci_abort_error(qdh->qdh_conn, 1, 336 HEC_QPACK_DECODER_STREAM_ERROR, "Error interpreting QPACK encoder " 337 "stream; offset %"PRIu64", line %d", qerr->off, qerr->line); 338 goto end; 339 } 340 if (qdh->qdh_dec_sm_out 341 && lsqpack_dec_ici_pending(&qdh->qdh_decoder)) 342 lsquic_stream_wantwrite(qdh->qdh_dec_sm_out, 1); 343 344 LSQ_DEBUG("successfully fed %zu bytes to QPACK decoder", sz); 345 346 end: 347 return sz; 348} 349 350 351static void 352qdh_in_on_read (struct lsquic_stream *stream, lsquic_stream_ctx_t *ctx) 353{ 354 struct qpack_dec_hdl *const qdh = (void *) ctx; 355 ssize_t nread; 356 357 nread = lsquic_stream_readf(stream, qdh_read_encoder_stream, qdh); 358 if (nread <= 0) 359 { 360 if (nread < 0) 361 { 362 LSQ_WARN("cannot read from encoder stream: %s", strerror(errno)); 363 qdh->qdh_conn->cn_if->ci_internal_error(qdh->qdh_conn, 364 "cannot read from encoder stream"); 365 } 366 else 367 { 368 LSQ_INFO("encoder stream closed by peer: abort connection"); 369 qdh->qdh_conn->cn_if->ci_abort_error(qdh->qdh_conn, 1, 370 HEC_CLOSED_CRITICAL_STREAM, "encoder stream closed"); 371 } 372 lsquic_stream_wantread(stream, 0); 373 } 374} 375 376 377static void 378qdh_in_on_close (struct lsquic_stream *stream, lsquic_stream_ctx_t *ctx) 379{ 380 struct qpack_dec_hdl *const qdh = (void *) ctx; 381 LSQ_DEBUG("closed incoming encoder stream"); 382 qdh->qdh_enc_sm_in = NULL; 383} 384 385 386static void 387qdh_in_on_write (struct lsquic_stream *stream, lsquic_stream_ctx_t *ctx) 388{ 389 assert(0); 390} 391 392 393static const struct lsquic_stream_if qdh_enc_sm_in_if = 394{ 395 .on_new_stream = qdh_in_on_new, 396 .on_read = qdh_in_on_read, 397 .on_write = qdh_in_on_write, 398 .on_close = qdh_in_on_close, 399}; 400const struct lsquic_stream_if *const lsquic_qdh_enc_sm_in_if = 401 &qdh_enc_sm_in_if; 402 403 404static void 405qdh_hblock_unblocked (void *stream_p) 406{ 407 struct lsquic_stream *const stream = stream_p; 408 union hblock_ctx *const u = stream->sm_hblock_ctx; 409 struct qpack_dec_hdl *qdh = u->ctx.qdh; 410 411 LSQ_DEBUG("header block for stream %"PRIu64" unblocked", stream->id); 412 lsquic_stream_qdec_unblocked(stream); 413} 414 415 416struct cont_len 417{ 418 unsigned long long value; 419 int has; /* 1: set, 0: not set, -1: invalid */ 420}; 421 422 423static void 424process_content_length (const struct qpack_dec_hdl *qdh /* for logging */, 425 struct cont_len *cl, const char *val /* not NUL-terminated */, 426 unsigned len) 427{ 428 char *endcl, cont_len_buf[30]; 429 430 if (0 == cl->has) 431 { 432 if (len >= sizeof(cont_len_buf)) 433 { 434 LSQ_DEBUG("content-length has invalid value `%.*s'", 435 (int) len, val); 436 cl->has = -1; 437 return; 438 } 439 memcpy(cont_len_buf, val, len); 440 cont_len_buf[len] = '\0'; 441 cl->value = strtoull(cont_len_buf, &endcl, 10); 442 if (*endcl == '\0' && !(ULLONG_MAX == cl->value && ERANGE == errno)) 443 { 444 cl->has = 1; 445 LSQ_DEBUG("content length is %llu", cl->value); 446 } 447 else 448 { 449 cl->has = -1; 450 LSQ_DEBUG("content-length has invalid value `%.*s'", 451 (int) len, val); 452 } 453 } 454 else if (cl->has > 0) 455 { 456 LSQ_DEBUG("header set has two content-length: ambiguous, " 457 "turn off checking"); 458 cl->has = -1; 459 } 460} 461 462 463static int 464is_content_length (const struct lsxpack_header *xhdr) 465{ 466 return ((xhdr->flags & LSXPACK_QPACK_IDX) 467 && xhdr->qpack_index == LSQPACK_TNV_CONTENT_LENGTH_0) 468 || (xhdr->name_len == 14 && 0 == memcmp(lsxpack_header_get_name(xhdr), 469 "content-length", 13)) 470 ; 471} 472 473 474static struct lsxpack_header * 475qdh_prepare_decode (void *stream_p, struct lsxpack_header *xhdr, size_t space) 476{ 477 struct lsquic_stream *const stream = stream_p; 478 union hblock_ctx *const u = stream->sm_hblock_ctx; 479 struct qpack_dec_hdl *const qdh = u->ctx.qdh; 480 481 return qdh->qdh_enpub->enp_hsi_if->hsi_prepare_decode( 482 u->ctx.hset, xhdr, space); 483} 484 485 486static int 487qdh_process_header (void *stream_p, struct lsxpack_header *xhdr) 488{ 489 struct lsquic_stream *const stream = stream_p; 490 union hblock_ctx *const u = stream->sm_hblock_ctx; 491 struct qpack_dec_hdl *const qdh = u->ctx.qdh; 492 struct cont_len cl; 493 494 if (is_content_length(xhdr)) 495 { 496 cl.has = 0; 497 process_content_length(qdh, &cl, lsxpack_header_get_value(xhdr), 498 xhdr->val_len); 499 if (cl.has > 0) 500 (void) lsquic_stream_verify_len(stream, cl.value); 501 } 502 503 return qdh->qdh_enpub->enp_hsi_if->hsi_process_header(u->ctx.hset, xhdr); 504} 505 506 507static const struct lsqpack_dec_hset_if dhi_if = 508{ 509 .dhi_unblocked = qdh_hblock_unblocked, 510 .dhi_prepare_decode = qdh_prepare_decode, 511 .dhi_process_header = qdh_process_header, 512}; 513 514 515static enum lsqpack_read_header_status 516qdh_header_read_results (struct qpack_dec_hdl *qdh, 517 struct lsquic_stream *stream, enum lsqpack_read_header_status rhs, 518 const unsigned char *dec_buf, size_t dec_buf_sz) 519{ 520 const struct lsqpack_dec_err *qerr; 521 struct uncompressed_headers *uh; 522 void *hset; 523 524 if (rhs == LQRHS_DONE) 525 { 526 if (!lsquic_stream_header_is_trailer(stream)) 527 { 528 hset = stream->sm_hblock_ctx->ctx.hset; 529 uh = &stream->sm_hblock_ctx->uh; 530 stream->sm_hblock_ctx = NULL; 531 memset(uh, 0, sizeof(*uh)); 532 uh->uh_stream_id = stream->id; 533 uh->uh_oth_stream_id = 0; 534 uh->uh_weight = 0; 535 uh->uh_exclusive = -1; 536 if (qdh->qdh_enpub->enp_hsi_if == lsquic_http1x_if) 537 uh->uh_flags |= UH_H1H; 538 if (0 != qdh->qdh_enpub->enp_hsi_if 539 ->hsi_process_header(hset, NULL)) 540 { 541 LSQ_DEBUG("finishing HTTP/1.x hset failed"); 542 free(uh); 543 return LQRHS_ERROR; 544 } 545 uh->uh_hset = hset; 546 if (0 == lsquic_stream_uh_in(stream, uh)) 547 LSQ_DEBUG("gave hset to stream %"PRIu64, stream->id); 548 else 549 { 550 LSQ_DEBUG("could not give hset to stream %"PRIu64, stream->id); 551 free(uh); 552 return LQRHS_ERROR; 553 } 554 } 555 else 556 { 557 LSQ_DEBUG("discard trailer header set"); 558 free(stream->sm_hblock_ctx); 559 stream->sm_hblock_ctx = NULL; 560 } 561 if (qdh->qdh_dec_sm_out) 562 { 563 if (dec_buf_sz 564 && 0 != qdh_write_decoder(qdh, dec_buf, dec_buf_sz)) 565 { 566 return LQRHS_ERROR; 567 } 568 if (dec_buf_sz || lsqpack_dec_ici_pending(&qdh->qdh_decoder)) 569 lsquic_stream_wantwrite(qdh->qdh_dec_sm_out, 1); 570 } 571 } 572 else if (rhs == LQRHS_ERROR) 573 { 574 qerr = lsqpack_dec_get_err_info(&qdh->qdh_decoder); 575 qdh->qdh_conn->cn_if->ci_abort_error(qdh->qdh_conn, 1, 576 HEC_QPACK_DECOMPRESSION_FAILED, "QPACK decompression error; " 577 "stream %"PRIu64", offset %"PRIu64", line %d", qerr->stream_id, 578 qerr->off, qerr->line); 579 } 580 581 return rhs; 582} 583 584 585enum lsqpack_read_header_status 586lsquic_qdh_header_in_begin (struct qpack_dec_hdl *qdh, 587 struct lsquic_stream *stream, uint64_t header_size, 588 const unsigned char **buf, size_t bufsz) 589{ 590 enum lsqpack_read_header_status rhs; 591 void *hset; 592 int is_pp; 593 size_t dec_buf_sz; 594 union hblock_ctx *u; 595 unsigned char dec_buf[LSQPACK_LONGEST_HEADER_ACK]; 596 597 assert(!(stream->stream_flags & STREAM_U_READ_DONE)); 598 599 if (!(qdh->qdh_flags & QDH_INITIALIZED)) 600 { 601 LSQ_WARN("not initialized: cannot process header block"); 602 return LQRHS_ERROR; 603 } 604 605 u = malloc(sizeof(*u)); 606 if (!u) 607 { 608 LSQ_INFO("cannot allocate hblock_ctx"); 609 return LQRHS_ERROR; 610 } 611 612 is_pp = lsquic_stream_header_is_pp(stream); 613 hset = qdh->qdh_enpub->enp_hsi_if->hsi_create_header_set( 614 qdh->qdh_hsi_ctx, stream, is_pp); 615 if (!hset) 616 { 617 free(u); 618 LSQ_DEBUG("hsi_create_header_set failure"); 619 return LQRHS_ERROR; 620 } 621 622 u->ctx.hset = hset; 623 u->ctx.qdh = qdh; 624 stream->sm_hblock_ctx = u; 625 626 dec_buf_sz = sizeof(dec_buf); 627 rhs = lsqpack_dec_header_in(&qdh->qdh_decoder, stream, stream->id, 628 header_size, buf, bufsz, dec_buf, &dec_buf_sz); 629 return qdh_header_read_results(qdh, stream, rhs, dec_buf, dec_buf_sz); 630} 631 632 633enum lsqpack_read_header_status 634lsquic_qdh_header_in_continue (struct qpack_dec_hdl *qdh, 635 struct lsquic_stream *stream, const unsigned char **buf, size_t bufsz) 636{ 637 enum lsqpack_read_header_status rhs; 638 size_t dec_buf_sz; 639 unsigned char dec_buf[LSQPACK_LONGEST_HEADER_ACK]; 640 641 assert(!(stream->stream_flags & STREAM_U_READ_DONE)); 642 643 if (qdh->qdh_flags & QDH_INITIALIZED) 644 { 645 dec_buf_sz = sizeof(dec_buf); 646 rhs = lsqpack_dec_header_read(&qdh->qdh_decoder, stream, 647 buf, bufsz, dec_buf, &dec_buf_sz); 648 return qdh_header_read_results(qdh, stream, rhs, dec_buf, dec_buf_sz); 649 } 650 else 651 { 652 LSQ_WARN("not initialized: cannot process header block"); 653 return LQRHS_ERROR; 654 } 655} 656 657 658static void 659lsquic_qdh_unref_stream (struct qpack_dec_hdl *qdh, 660 struct lsquic_stream *stream) 661{ 662 if (0 == lsqpack_dec_unref_stream(&qdh->qdh_decoder, stream)) 663 LSQ_DEBUG("unreffed stream %"PRIu64, stream->id); 664 else 665 LSQ_WARN("cannot unref stream %"PRIu64, stream->id); 666} 667 668 669void 670lsquic_qdh_cancel_stream (struct qpack_dec_hdl *qdh, 671 struct lsquic_stream *stream) 672{ 673 ssize_t nw; 674 unsigned char buf[LSQPACK_LONGEST_CANCEL]; 675 676 if (!qdh->qdh_dec_sm_out) 677 return; 678 679 nw = lsqpack_dec_cancel_stream(&qdh->qdh_decoder, stream, buf, sizeof(buf)); 680 if (nw > 0) 681 { 682 if (0 == qdh_write_decoder(qdh, buf, nw)) 683 LSQ_DEBUG("cancelled stream %"PRIu64" and wrote %zd-byte Cancel " 684 "Stream instruction to the decoder stream", stream->id, nw); 685 } 686 else if (nw == 0) 687 LSQ_WARN("cannot cancel stream %"PRIu64" -- not found", stream->id); 688 else 689 { 690 LSQ_WARN("cannot cancel stream %"PRIu64" -- not enough buffer space " 691 "to encode Cancel Stream instructin", stream->id); 692 lsquic_qdh_unref_stream(qdh, stream); 693 } 694} 695 696 697void 698lsquic_qdh_cancel_stream_id (struct qpack_dec_hdl *qdh, 699 lsquic_stream_id_t stream_id) 700{ 701 ssize_t nw; 702 unsigned char buf[LSQPACK_LONGEST_CANCEL]; 703 704 if (!qdh->qdh_dec_sm_out) 705 return; 706 707 nw = lsqpack_dec_cancel_stream_id(&qdh->qdh_decoder, stream_id, buf, 708 sizeof(buf)); 709 if (nw > 0) 710 { 711 if (0 == qdh_write_decoder(qdh, buf, nw)) 712 LSQ_DEBUG("wrote %zd-byte Cancel Stream instruction for " 713 "stream %"PRIu64" to the decoder stream", nw, stream_id); 714 } 715 else if (nw == 0) 716 LSQ_DEBUG("not generating Cancel Stream instruction for " 717 "stream %"PRIu64, stream_id); 718 else 719 LSQ_WARN("cannot generate Cancel Stream instruction for " 720 "stream %"PRIu64" -- not enough buffer space", stream_id); 721} 722 723 724int 725lsquic_qdh_arm_if_unsent (struct qpack_dec_hdl *qdh, void (*func)(void *), 726 void *ctx) 727{ 728 size_t bytes; 729 730 /* Use size of a single frab list buffer as an arbitrary threshold */ 731 bytes = lsquic_frab_list_size(&qdh->qdh_fral); 732 if (bytes <= qdh->qdh_fral.fl_buf_size) 733 return 0; 734 else 735 { 736 LSQ_DEBUG("have %zu bytes of unsent QPACK decoder stream data: set " 737 "up callback", bytes); 738 qdh->qdh_on_dec_sent_func = func; 739 qdh->qdh_on_dec_sent_ctx = ctx; 740 return 1; 741 } 742} 743