/* MIT License Copyright (c) 2018 - 2021 LiteSpeed Technologies Inc Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ #include #include #include #include #include #include "lshpack.h" #if LS_HPACK_EMIT_TEST_CODE #include "lshpack-test.h" #endif #include XXH_HEADER_NAME #ifndef LS_HPACK_USE_LARGE_TABLES #define LS_HPACK_USE_LARGE_TABLES 1 #endif #include "huff-tables.h" #define HPACK_STATIC_TABLE_SIZE 61 #define INITIAL_DYNAMIC_TABLE_SIZE 4096 /* RFC 7541, Section 4.1: * * " The size of the dynamic table is the sum of the size of its entries. * " * " The size of an entry is the sum of its name's length in octets (as * " defined in Section 5.2), its value's length in octets, and 32. */ #define DYNAMIC_ENTRY_OVERHEAD 32 #define NAME_VAL(a, b) sizeof(a) - 1, sizeof(b) - 1, (a), (b) static const struct { unsigned name_len; unsigned val_len; const char *name; const char *val; } static_table[HPACK_STATIC_TABLE_SIZE] = { { NAME_VAL(":authority", "") }, { NAME_VAL(":method", "GET") }, { NAME_VAL(":method", "POST") }, { NAME_VAL(":path", "/") }, { NAME_VAL(":path", "/index.html") }, { NAME_VAL(":scheme", "http") }, { NAME_VAL(":scheme", "https") }, { NAME_VAL(":status", "200") }, { NAME_VAL(":status", "204") }, { NAME_VAL(":status", "206") }, { NAME_VAL(":status", "304") }, { NAME_VAL(":status", "400") }, { NAME_VAL(":status", "404") }, { NAME_VAL(":status", "500") }, { NAME_VAL("accept-charset", "") }, { NAME_VAL("accept-encoding", "gzip, deflate") }, { NAME_VAL("accept-language", "") }, { NAME_VAL("accept-ranges", "") }, { NAME_VAL("accept", "") }, { NAME_VAL("access-control-allow-origin", "") }, { NAME_VAL("age", "") }, { NAME_VAL("allow", "") }, { NAME_VAL("authorization", "") }, { NAME_VAL("cache-control", "") }, { NAME_VAL("content-disposition", "") }, { NAME_VAL("content-encoding", "") }, { NAME_VAL("content-language", "") }, { NAME_VAL("content-length", "") }, { NAME_VAL("content-location", "") }, { NAME_VAL("content-range", "") }, { NAME_VAL("content-type", "") }, { NAME_VAL("cookie", "") }, { NAME_VAL("date", "") }, { NAME_VAL("etag", "") }, { NAME_VAL("expect", "") }, { NAME_VAL("expires", "") }, { NAME_VAL("from", "") }, { NAME_VAL("host", "") }, { NAME_VAL("if-match", "") }, { NAME_VAL("if-modified-since", "") }, { NAME_VAL("if-none-match", "") }, { NAME_VAL("if-range", "") }, { NAME_VAL("if-unmodified-since", "") }, { NAME_VAL("last-modified", "") }, { NAME_VAL("link", "") }, { NAME_VAL("location", "") }, { NAME_VAL("max-forwards", "") }, { NAME_VAL("proxy-authenticate", "") }, { NAME_VAL("proxy-authorization", "") }, { NAME_VAL("range", "") }, { NAME_VAL("referer", "") }, { NAME_VAL("refresh", "") }, { NAME_VAL("retry-after", "") }, { NAME_VAL("server", "") }, { NAME_VAL("set-cookie", "") }, { NAME_VAL("strict-transport-security", "") }, { NAME_VAL("transfer-encoding", "") }, { NAME_VAL("user-agent", "") }, { NAME_VAL("vary", "") }, { NAME_VAL("via", "") }, { NAME_VAL("www-authenticate", "") } }; static const uint32_t static_table_name_hash[HPACK_STATIC_TABLE_SIZE] = { 0x653A915Bu, 0xC7742BE4u, 0xC7742BE4u, 0x3513518Du, 0x3513518Du, 0xF49F1451u, 0xF49F1451u, 0x672BDA53u, 0x672BDA53u, 0x672BDA53u, 0x672BDA53u, 0x672BDA53u, 0x672BDA53u, 0x672BDA53u, 0xCD2C0296u, 0xF93AD8A9u, 0x98BD32D3u, 0x1DC691C8u, 0x1AB214F8u, 0x7D3B7A3Bu, 0xBEC8E440u, 0xE9C1D9E1u, 0x19D88141u, 0xC25511F2u, 0x16020A90u, 0x48011191u, 0x7D9AAB7Eu, 0x48F5CC19u, 0x8847A08Cu, 0x0D19F766u, 0x085EF7C5u, 0x0B486ED8u, 0x1A7AA369u, 0x6DE855BAu, 0xA6006EFDu, 0xA1BB4284u, 0xAE56E25Fu, 0xB6787110u, 0x791C6A0Du, 0xF2BADABEu, 0xD8CA2594u, 0xFBA64C54u, 0x4BEB0951u, 0x6B86C0B5u, 0xC62FECD2u, 0x8DA64A26u, 0x6CA35045u, 0xF614D165u, 0xE4D1DF14u, 0xB396750Au, 0x01F10233u, 0x798BEE18u, 0x5239F142u, 0x82E1B4E1u, 0x8F7E493Eu, 0x85E74C58u, 0xBD17F160u, 0x34C0456Au, 0x1A04DF3Du, 0xB1B15AB2u, 0xDDDAB6FFu, }; static const uint32_t static_table_nameval_hash[HPACK_STATIC_TABLE_SIZE] = { 0xF8614896u, 0x25D95A15u, 0x33968BB7u, 0xC8C267F6u, 0x8351136Fu, 0x98573F68u, 0x16DDE443u, 0x352A6556u, 0xD4F462D2u, 0x125E66E0u, 0xD7988BC9u, 0x4C3C90DEu, 0x65E6ECA1u, 0xB05B7B87u, 0x96816317u, 0x8BBF5398u, 0x97E01849u, 0xD7B48DD4u, 0x9C180569u, 0xC7C63B45u, 0xF4223EE5u, 0x12C8A744u, 0xAA95A0BCu, 0x14F65730u, 0x8410A906u, 0x98F440DDu, 0x627E4803u, 0x5A5CC325u, 0x137FC223u, 0x1529262Fu, 0x7950B9BDu, 0x51D448A4u, 0x52C167CFu, 0xFB22AA54u, 0x540DB9FEu, 0x75A6C685u, 0xE1C54196u, 0xDC0C3733u, 0x6D78CB84u, 0x4F5272CDu, 0x9D4170E4u, 0xD4E28BA1u, 0x028C7846u, 0x4E8C1DC3u, 0x684BDDBCu, 0xE113A2B0u, 0x55F7BBD1u, 0x15BD3710u, 0xE82B715Du, 0x3674BC1Fu, 0x5010D24Bu, 0x953DE1CBu, 0x9F2C92D9u, 0xB2DE5570u, 0xBCA5998Fu, 0x0FF5B88Eu, 0x1FED156Bu, 0xDC83E7ECu, 0x07B79E35u, 0xA6D145A9u, 0x43638CBAu, }; #define lshpack_arr_init(a) do { \ memset((a), 0, sizeof(*(a))); \ } while (0) #define lshpack_arr_cleanup(a) do { \ free((a)->els); \ memset((a), 0, sizeof(*(a))); \ } while (0) #define lshpack_arr_get(a, i) ( \ assert((i) < (a)->nelem), \ (a)->els[(a)->off + (i)] \ ) #define lshpack_arr_shift(a) ( \ assert((a)->nelem > 0), \ (a)->nelem -= 1, \ (a)->els[(a)->off++] \ ) #define lshpack_arr_pop(a) ( \ assert((a)->nelem > 0), \ (a)->nelem -= 1, \ (a)->els[(a)->off + (a)->nelem] \ ) #define lshpack_arr_count(a) (+(a)->nelem) static int lshpack_arr_push (struct lshpack_arr *arr, uintptr_t val) { uintptr_t *new_els; unsigned n; if (arr->off + arr->nelem < arr->nalloc) { arr->els[arr->off + arr->nelem] = val; ++arr->nelem; return 0; } if (arr->off > arr->nalloc / 2) { memmove(arr->els, arr->els + arr->off, sizeof(arr->els[0]) * arr->nelem); arr->off = 0; arr->els[arr->nelem] = val; ++arr->nelem; return 0; } if (arr->nalloc) n = arr->nalloc * 2; else n = 64; new_els = malloc(n * sizeof(arr->els[0])); if (!new_els) return -1; memcpy(new_els, arr->els + arr->off, sizeof(arr->els[0]) * arr->nelem); free(arr->els); arr->off = 0; arr->els = new_els; arr->nalloc = n; arr->els[arr->off + arr->nelem] = val; ++arr->nelem; return 0; } struct lshpack_double_enc_head { struct lshpack_enc_head by_name; struct lshpack_enc_head by_nameval; }; struct lshpack_enc_table_entry { /* An entry always lives on the `all' and `nameval' lists. If its name * is not in the static table, it also lives on the `name' list. */ STAILQ_ENTRY(lshpack_enc_table_entry) ete_next_nameval, ete_next_name, ete_next_all; unsigned ete_id; unsigned ete_nameval_hash; unsigned ete_name_hash; unsigned ete_name_len; unsigned ete_val_len; char ete_buf[]; }; #define ETE_NAME(ete) ((ete)->ete_buf) #define ETE_VALUE(ete) (&(ete)->ete_buf[(ete)->ete_name_len]) #define N_BUCKETS(n_bits) (1U << (n_bits)) #define BUCKNO(n_bits, hash) ((hash) & (N_BUCKETS(n_bits) - 1)) /* We estimate average number of entries in the dynamic table to be 1/3 * of the theoretical maximum. This number is used to size the history * buffer: we want it large enough to cover recent entries, yet not too * large to cover entries that appear with a period larger than the * dynamic table. */ static unsigned henc_hist_size (unsigned max_capacity) { return max_capacity / DYNAMIC_ENTRY_OVERHEAD / 3; } int lshpack_enc_init (struct lshpack_enc *enc) { struct lshpack_double_enc_head *buckets; unsigned nbits = 2; unsigned i; buckets = malloc(sizeof(buckets[0]) * N_BUCKETS(nbits)); if (!buckets) return -1; for (i = 0; i < N_BUCKETS(nbits); ++i) { STAILQ_INIT(&buckets[i].by_name); STAILQ_INIT(&buckets[i].by_nameval); } memset(enc, 0, sizeof(*enc)); STAILQ_INIT(&enc->hpe_all_entries); enc->hpe_max_capacity = INITIAL_DYNAMIC_TABLE_SIZE; enc->hpe_buckets = buckets; /* The initial value of the entry ID is completely arbitrary. As long as * there are fewer than 2^32 dynamic table entries, the math to calculate * the entry ID works. To prove to ourselves that the wraparound works * and to have the unit tests cover it, we initialize the next ID so that * it is just about to wrap around. */ enc->hpe_next_id = ~0 - 3; enc->hpe_nbits = nbits; enc->hpe_nelem = 0; return 0; } void lshpack_enc_cleanup (struct lshpack_enc *enc) { struct lshpack_enc_table_entry *entry, *next; for (entry = STAILQ_FIRST(&enc->hpe_all_entries); entry; entry = next) { next = STAILQ_NEXT(entry, ete_next_all); free(entry); } free(enc->hpe_hist_buf); free(enc->hpe_buckets); } static int henc_use_hist (struct lshpack_enc *enc) { unsigned hist_size; if (enc->hpe_hist_buf) return 0; hist_size = henc_hist_size(INITIAL_DYNAMIC_TABLE_SIZE); if (!hist_size) return 0; enc->hpe_hist_buf = malloc(sizeof(enc->hpe_hist_buf[0]) * (hist_size + 1)); if (!enc->hpe_hist_buf) return -1; enc->hpe_hist_size = hist_size; enc->hpe_flags |= LSHPACK_ENC_USE_HIST; return 0; } int lshpack_enc_use_hist (struct lshpack_enc *enc, int on) { if (on) return henc_use_hist(enc); else { enc->hpe_flags &= ~LSHPACK_ENC_USE_HIST; free(enc->hpe_hist_buf); enc->hpe_hist_buf = NULL; enc->hpe_hist_size = 0; enc->hpe_hist_idx = 0; enc->hpe_hist_wrapped = 0; return 0; } } int lshpack_enc_hist_used (const struct lshpack_enc *enc) { return (enc->hpe_flags & LSHPACK_ENC_USE_HIST) != 0; } #define LSHPACK_XXH_SEED 39378473 #define XXH_NAMEVAL_WIDTH 9 #define XXH_NAMEVAL_SHIFT 0 #define XXH_NAME_WIDTH 9 #define XXH_NAME_SHIFT 0 static const unsigned char nameval2id[ 1 << XXH_NAMEVAL_WIDTH ] = { [150] = 1, [21] = 2, [439] = 3, [502] = 4, [367] = 5, [360] = 6, [67] = 7, [342] = 8, [210] = 9, [224] = 10, [457] = 11, [222] = 12, [161] = 13, [391] = 14, [279] = 15, [408] = 16, [73] = 17, [468] = 18, [361] = 19, [325] = 20, [229] = 21, [324] = 22, [188] = 23, [304] = 24, [262] = 25, [221] = 26, [3] = 27, [293] = 28, [35] = 29, [47] = 30, [445] = 31, [164] = 32, [463] = 33, [84] = 34, [510] = 35, [133] = 36, [406] = 37, [307] = 38, [388] = 39, [205] = 40, [228] = 41, [417] = 42, [70] = 43, [451] = 44, [444] = 45, [176] = 46, [465] = 47, [272] = 48, [349] = 49, [31] = 50, [75] = 51, [459] = 52, [217] = 53, [368] = 54, [399] = 55, [142] = 56, [363] = 57, [492] = 58, [53] = 59, [425] = 60, [186] = 61, }; static const unsigned char name2id[ 1 << XXH_NAME_WIDTH ] = { [347] = 1, [484] = 2, [397] = 4, [81] = 6, [83] = 8, [150] = 15, [169] = 16, [211] = 17, [456] = 18, [248] = 19, [59] = 20, [64] = 21, [481] = 22, [321] = 23, [498] = 24, [144] = 25, [401] = 26, [382] = 27, [25] = 28, [140] = 29, [358] = 30, [453] = 31, [216] = 32, [361] = 33, [442] = 34, [253] = 35, [132] = 36, [95] = 37, [272] = 38, [13] = 39, [190] = 40, [404] = 41, [84] = 42, [337] = 43, [181] = 44, [210] = 45, [38] = 46, [69] = 47, [357] = 48, [276] = 49, [266] = 50, [51] = 51, [24] = 52, [322] = 53, [225] = 54, [318] = 55, [88] = 56, [352] = 57, [362] = 58, [317] = 59, [178] = 60, [255] = 61, }; //not find return 0, otherwise return the index #if !LS_HPACK_EMIT_TEST_CODE static #endif unsigned lshpack_enc_get_static_nameval (const struct lsxpack_header *input) { unsigned i; assert(input->name_len > 0); assert(input->flags & LSXPACK_NAMEVAL_HASH); i = (input->nameval_hash >> XXH_NAMEVAL_SHIFT) & ((1 << XXH_NAMEVAL_WIDTH) - 1); if (nameval2id[i]) { i = nameval2id[i] - 1; if (static_table[i].name_len == input->name_len && static_table[i].val_len == input->val_len && memcmp(lsxpack_header_get_name(input), static_table[i].name, input->name_len) == 0 && memcmp(lsxpack_header_get_value(input), static_table[i].val, input->val_len) == 0) { return i + 1; } } return 0; } #if !LS_HPACK_EMIT_TEST_CODE static #endif unsigned lshpack_enc_get_static_name (const struct lsxpack_header *input) { unsigned i; assert(input->flags & LSXPACK_NAME_HASH); i = (input->name_hash >> XXH_NAME_SHIFT) & ((1 << XXH_NAME_WIDTH) - 1); if (name2id[i]) { i = name2id[i] - 1; if (static_table[i].name_len == input->name_len && memcmp(lsxpack_header_get_name(input), static_table[i].name, input->name_len) == 0) { return i + 1; } } return 0; } static void update_hash (struct lsxpack_header *input) { if (!(input->flags & LSXPACK_NAME_HASH)) input->name_hash = XXH32(lsxpack_header_get_name(input), input->name_len, LSHPACK_XXH_SEED); else assert(input->name_hash == XXH32(lsxpack_header_get_name(input), input->name_len, LSHPACK_XXH_SEED)); if (!(input->flags & LSXPACK_NAMEVAL_HASH)) input->nameval_hash = XXH32(input->buf + input->val_offset, input->val_len, input->name_hash); else assert(input->nameval_hash == XXH32(input->buf + input->val_offset, input->val_len, input->name_hash)); input->flags |= (LSXPACK_NAME_HASH | LSXPACK_NAMEVAL_HASH); } unsigned lshpack_enc_get_stx_tab_id (struct lsxpack_header *input) { unsigned i; update_hash(input); i = (input->nameval_hash >> XXH_NAMEVAL_SHIFT) & ((1 << XXH_NAMEVAL_WIDTH) - 1); if (nameval2id[i]) { i = nameval2id[i] - 1; if (static_table[i].name_len == input->name_len && static_table[i].val_len == input->val_len && memcmp(lsxpack_header_get_name(input), static_table[i].name, input->name_len) == 0 && memcmp(input->buf + input->val_offset, static_table[i].val, input->val_len) == 0) { return i + 1; } } i = (input->name_hash >> XXH_NAME_SHIFT) & ((1 << XXH_NAME_WIDTH) - 1); if (name2id[i]) { i = name2id[i] - 1; if (static_table[i].name_len == input->name_len && memcmp(lsxpack_header_get_name(input), static_table[i].name, input->name_len) == 0) { return i + 1; } } return 0; } /* Given a dynamic entry, return its table ID */ static unsigned henc_calc_table_id (const struct lshpack_enc *enc, const struct lshpack_enc_table_entry *entry) { return HPACK_STATIC_TABLE_SIZE + (enc->hpe_next_id - entry->ete_id) ; } static unsigned henc_find_table_id (struct lshpack_enc *enc, lsxpack_header_t *input, int *val_matched) { struct lshpack_enc_table_entry *entry; unsigned buckno, id; const char *val_ptr = input->buf + input->val_offset; const char *name; unsigned int name_len; name_len = input->name_len; name = lsxpack_header_get_name(input); /* First, look for a match in the static table: */ if (input->hpack_index) { id = input->hpack_index - 1; #ifndef NDEBUG if (name_len) { lsxpack_header_t input_copy = *input; const unsigned hpack_index = lshpack_enc_get_stx_tab_id(&input_copy); assert(input_copy.hpack_index == hpack_index); } #endif if (id <= LSHPACK_HDR_ACCEPT_ENCODING || input->val_len == 0) { if (static_table[id].val_len == input->val_len && memcmp(val_ptr, static_table[id].val, input->val_len) == 0) { input->flags |= LSXPACK_HPACK_VAL_MATCHED; *val_matched = 1; return input->hpack_index; } } if (!name_len) { name = static_table[id].name; name_len = static_table[id].name_len; } if (!(input->flags & LSXPACK_NAME_HASH)) input->name_hash = static_table_name_hash[id]; else assert(input->name_hash == static_table_name_hash[id]); if (!(input->flags & LSXPACK_NAMEVAL_HASH)) input->nameval_hash = XXH32(val_ptr, input->val_len, input->name_hash); else assert(input->nameval_hash == XXH32(val_ptr, input->val_len, input->name_hash)); input->flags |= (LSXPACK_NAME_HASH | LSXPACK_NAMEVAL_HASH); } else { update_hash(input); input->hpack_index = lshpack_enc_get_static_nameval(input); if (input->hpack_index != LSHPACK_HDR_UNKNOWN) { input->flags |= LSXPACK_HPACK_VAL_MATCHED; *val_matched = 1; return input->hpack_index; } } /* Search by name and value: */ buckno = BUCKNO(enc->hpe_nbits, input->nameval_hash); STAILQ_FOREACH(entry, &enc->hpe_buckets[buckno].by_nameval, ete_next_nameval) if (input->nameval_hash == entry->ete_nameval_hash && name_len == entry->ete_name_len && input->val_len == entry->ete_val_len && 0 == memcmp(name, ETE_NAME(entry), name_len) && 0 == memcmp(val_ptr, ETE_VALUE(entry), input->val_len)) { *val_matched = 1; return henc_calc_table_id(enc, entry); } /* Name/value match is not found, look for header: */ if (input->hpack_index == LSHPACK_HDR_UNKNOWN) input->hpack_index = lshpack_enc_get_static_name(input); if (input->hpack_index != LSHPACK_HDR_UNKNOWN) { input->flags &= ~LSXPACK_HPACK_VAL_MATCHED; return input->hpack_index; } /* Search by name only: */ buckno = BUCKNO(enc->hpe_nbits, input->name_hash); STAILQ_FOREACH(entry, &enc->hpe_buckets[buckno].by_name, ete_next_name) if (input->name_hash == entry->ete_name_hash && input->name_len == entry->ete_name_len && 0 == memcmp(name, ETE_NAME(entry), name_len)) { input->flags &= ~LSXPACK_HPACK_VAL_MATCHED; return henc_calc_table_id(enc, entry); } return 0; } #if !LS_HPACK_EMIT_TEST_CODE static #endif unsigned char * lshpack_enc_enc_int (unsigned char *dst, unsigned char *const end, uint32_t value, uint8_t prefix_bits) { unsigned char *const dst_orig = dst; /* This function assumes that at least one byte is available */ assert(dst < end); if (value < (uint32_t)(1 << prefix_bits) - 1) *dst++ |= value; else { *dst++ |= (1 << prefix_bits) - 1; value -= (1 << prefix_bits) - 1; while (value >= 128) { if (dst < end) { *dst++ = (0x80 | value); value >>= 7; } else return dst_orig; } if (dst < end) *dst++ = value; else return dst_orig; } return dst; } /* This whole pragma business has to do with turning off uninitialized warnings. * We do it for gcc and clang. Other compilers get slightly slower code, where * unnecessary initialization is performed. */ #if __GNUC__ #pragma GCC diagnostic ignored "-Wunknown-pragmas" #if __clang__ #pragma GCC diagnostic ignored "-Wunknown-warning-option" #endif #endif int lshpack_enc_huff_encode (const unsigned char *src, const unsigned char *const src_end, unsigned char *const dst, int dst_len) { unsigned char *p_dst = dst; unsigned char *dst_end = p_dst + dst_len; uintptr_t bits; /* OK not to initialize this variable */ unsigned bits_used = 0, adj; struct encode_el cur_enc_code; #if __GNUC__ #pragma GCC diagnostic push #pragma GCC diagnostic ignored "-Wmaybe-uninitialized" #pragma GCC diagnostic ignored "-Wuninitialized" #else bits = 0; #endif #if LS_HPACK_USE_LARGE_TABLES const struct henc *henc; uint16_t idx; while (src + sizeof(bits) * 8 / 5 + sizeof(idx) < src_end && p_dst + sizeof(bits) <= dst_end) { memcpy(&idx, src, 2); henc = &hencs[idx]; src += 2; while (bits_used + henc->lens < sizeof(bits) * 8) { bits <<= henc->lens; bits |= henc->code; bits_used += henc->lens; memcpy(&idx, src, 2); henc = &hencs[idx]; src += 2; } if (henc->lens < 64) { bits <<= sizeof(bits) * 8 - bits_used; bits_used = henc->lens - (sizeof(bits) * 8 - bits_used); bits |= henc->code >> bits_used; #if UINTPTR_MAX == 18446744073709551615ull *p_dst++ = bits >> 56; *p_dst++ = bits >> 48; *p_dst++ = bits >> 40; *p_dst++ = bits >> 32; #endif *p_dst++ = bits >> 24; *p_dst++ = bits >> 16; *p_dst++ = bits >> 8; *p_dst++ = bits; bits = henc->code; /* OK not to clear high bits */ } else { src -= 2; break; } } #endif while (src != src_end) { cur_enc_code = encode_table[*src++]; if (bits_used + cur_enc_code.bits < sizeof(bits) * 8) { bits <<= cur_enc_code.bits; bits |= cur_enc_code.code; bits_used += cur_enc_code.bits; continue; } else if (p_dst + sizeof(bits) <= dst_end) { bits <<= sizeof(bits) * 8 - bits_used; bits_used = cur_enc_code.bits - (sizeof(bits) * 8 - bits_used); bits |= cur_enc_code.code >> bits_used; #if UINTPTR_MAX == 18446744073709551615ull *p_dst++ = bits >> 56; *p_dst++ = bits >> 48; *p_dst++ = bits >> 40; *p_dst++ = bits >> 32; #endif *p_dst++ = bits >> 24; *p_dst++ = bits >> 16; *p_dst++ = bits >> 8; *p_dst++ = bits; bits = cur_enc_code.code; /* OK not to clear high bits */ } else return -1; } adj = bits_used + (-bits_used & 7); /* Round up to 8 */ if (bits_used && p_dst + (adj >> 3) <= dst_end) { bits <<= -bits_used & 7; /* Align to byte boundary */ bits |= ((1 << (-bits_used & 7)) - 1); /* EOF */ switch (adj >> 3) { /* Write out */ #if UINTPTR_MAX == 18446744073709551615ull case 8: *p_dst++ = bits >> 56; /* fall through */ case 7: *p_dst++ = bits >> 48; /* fall through */ case 6: *p_dst++ = bits >> 40; /* fall through */ case 5: *p_dst++ = bits >> 32; #endif /* fall through */ case 4: *p_dst++ = bits >> 24; /* fall through */ case 3: *p_dst++ = bits >> 16; /* fall through */ case 2: *p_dst++ = bits >> 8; /* fall through */ default: *p_dst++ = bits; } return p_dst - dst; } else if (p_dst + (adj >> 3) <= dst_end) return p_dst - dst; else return -1; #if __GNUC__ #pragma GCC diagnostic pop #endif } #if !LS_HPACK_EMIT_TEST_CODE static #endif int lshpack_enc_enc_str (unsigned char *const dst, size_t dst_len, const unsigned char *str, unsigned str_len) { unsigned char size_buf[4]; unsigned char *p; unsigned size_len; int rc; if (dst_len > 1) /* We guess that the string size fits into a single byte -- meaning * compressed string of size 126 and smaller -- which is the normal * case. Thus, we immediately write compressed string to the output * buffer. If our guess is not correct, we fix it later. */ rc = lshpack_enc_huff_encode(str, str + str_len, dst + 1, dst_len - 1); else if (dst_len == 1) /* Here, the call can only succeed if the string to encode is empty. */ rc = 0; else return -1; /* * Check if need huffman encoding or not * Comment: (size_t)rc <= str_len = means if same length, still use * Huffman * ^ */ if (rc > 0 && (size_t)rc <= str_len) { if (rc < 127) { *dst = 0x80 | rc; return 1 + rc; } size_buf[0] = 0x80; str_len = rc; str = dst + 1; } else if (str_len <= dst_len - 1) { if (str_len < 127) { *dst = (unsigned char) str_len; memcpy(dst + 1, str, str_len); return 1 + str_len; } size_buf[0] = 0x00; } else return -1; /* The guess of one-byte size was incorrect. Perform necessary * adjustments. */ p = lshpack_enc_enc_int(size_buf, size_buf + sizeof(size_buf), str_len, 7); if (p == size_buf) return -1; size_len = p - size_buf; assert(size_len > 1); /* Check if there is enough room in the output buffer for both * encoded size and the string. */ if (size_len + str_len > dst_len) return -1; memmove(dst + size_len, str, str_len); memcpy(dst, size_buf, size_len); return size_len + str_len; } static void henc_drop_oldest_entry (struct lshpack_enc *enc) { struct lshpack_enc_table_entry *entry; unsigned buckno; entry = STAILQ_FIRST(&enc->hpe_all_entries); assert(entry); STAILQ_REMOVE_HEAD(&enc->hpe_all_entries, ete_next_all); buckno = BUCKNO(enc->hpe_nbits, entry->ete_nameval_hash); assert(entry == STAILQ_FIRST(&enc->hpe_buckets[buckno].by_nameval)); STAILQ_REMOVE_HEAD(&enc->hpe_buckets[buckno].by_nameval, ete_next_nameval); buckno = BUCKNO(enc->hpe_nbits, entry->ete_name_hash); if (entry == STAILQ_FIRST(&enc->hpe_buckets[buckno].by_name)) STAILQ_REMOVE_HEAD(&enc->hpe_buckets[buckno].by_name, ete_next_name); enc->hpe_cur_capacity -= DYNAMIC_ENTRY_OVERHEAD + entry->ete_name_len + entry->ete_val_len; --enc->hpe_nelem; free(entry); } static void henc_remove_overflow_entries (struct lshpack_enc *enc) { while (enc->hpe_cur_capacity > enc->hpe_max_capacity) henc_drop_oldest_entry(enc); } static int henc_grow_tables (struct lshpack_enc *enc) { struct lshpack_double_enc_head *new_buckets, *new[2]; struct lshpack_enc_table_entry *entry; unsigned n, old_nbits; int idx; old_nbits = enc->hpe_nbits; new_buckets = malloc(sizeof(enc->hpe_buckets[0]) * N_BUCKETS(old_nbits + 1)); if (!new_buckets) return -1; for (n = 0; n < N_BUCKETS(old_nbits); ++n) { new[0] = &new_buckets[n]; new[1] = &new_buckets[n + N_BUCKETS(old_nbits)]; STAILQ_INIT(&new[0]->by_name); STAILQ_INIT(&new[1]->by_name); STAILQ_INIT(&new[0]->by_nameval); STAILQ_INIT(&new[1]->by_nameval); while ((entry = STAILQ_FIRST(&enc->hpe_buckets[n].by_name))) { STAILQ_REMOVE_HEAD(&enc->hpe_buckets[n].by_name, ete_next_name); idx = (BUCKNO(old_nbits + 1, entry->ete_name_hash) >> old_nbits) & 1; STAILQ_INSERT_TAIL(&new[idx]->by_name, entry, ete_next_name); } while ((entry = STAILQ_FIRST(&enc->hpe_buckets[n].by_nameval))) { STAILQ_REMOVE_HEAD(&enc->hpe_buckets[n].by_nameval, ete_next_nameval); idx = (BUCKNO(old_nbits + 1, entry->ete_nameval_hash) >> old_nbits) & 1; STAILQ_INSERT_TAIL(&new[idx]->by_nameval, entry, ete_next_nameval); } } free(enc->hpe_buckets); enc->hpe_nbits = old_nbits + 1; enc->hpe_buckets = new_buckets; return 0; } #if !LS_HPACK_EMIT_TEST_CODE static #endif int lshpack_enc_push_entry (struct lshpack_enc *enc, const struct lsxpack_header *input) { unsigned buckno; struct lshpack_enc_table_entry *entry; size_t size; const char *name; unsigned int name_len; if (enc->hpe_nelem >= N_BUCKETS(enc->hpe_nbits) / 2 && 0 != henc_grow_tables(enc)) return -1; name_len = input->name_len; if (name_len == 0) { assert(input->hpack_index != LSHPACK_HDR_UNKNOWN); name = static_table[input->hpack_index - 1].name; name_len = static_table[input->hpack_index - 1].name_len; } else name = lsxpack_header_get_name(input); size = sizeof(*entry) + name_len + input->val_len; entry = malloc(size); if (!entry) return -1; entry->ete_name_hash = input->name_hash; entry->ete_nameval_hash = input->nameval_hash; entry->ete_name_len = name_len; entry->ete_val_len = input->val_len; entry->ete_id = enc->hpe_next_id++; memcpy(ETE_NAME(entry), name, name_len); memcpy(ETE_VALUE(entry), input->buf + input->val_offset, input->val_len); STAILQ_INSERT_TAIL(&enc->hpe_all_entries, entry, ete_next_all); buckno = BUCKNO(enc->hpe_nbits, input->nameval_hash); STAILQ_INSERT_TAIL(&enc->hpe_buckets[buckno].by_nameval, entry, ete_next_nameval); if (input->hpack_index == LSHPACK_HDR_UNKNOWN) { buckno = BUCKNO(enc->hpe_nbits, input->name_hash); STAILQ_INSERT_TAIL(&enc->hpe_buckets[buckno].by_name, entry, ete_next_name); } enc->hpe_cur_capacity += DYNAMIC_ENTRY_OVERHEAD + name_len + input->val_len; ++enc->hpe_nelem; henc_remove_overflow_entries(enc); return 0; } static void henc_resize_history (struct lshpack_enc *enc) { uint32_t *hist_buf; unsigned hist_size, first, count, i, j; hist_size = henc_hist_size(enc->hpe_max_capacity); if (hist_size == enc->hpe_hist_size) return; if (hist_size == 0) { free(enc->hpe_hist_buf); enc->hpe_hist_buf = NULL; enc->hpe_hist_size = 0; enc->hpe_hist_idx = 0; enc->hpe_hist_wrapped = 0; return; } hist_buf = malloc(sizeof(hist_buf[0]) * (hist_size + 1)); if (!hist_buf) return; if (enc->hpe_hist_wrapped) { first = (enc->hpe_hist_idx + 1) % enc->hpe_hist_size; count = enc->hpe_hist_size; } else { first = 0; count = enc->hpe_hist_idx; } for (i = 0, j = 0; count > 0 && j < hist_size; ++i, ++j, --count) hist_buf[j] = enc->hpe_hist_buf[ (first + i) % enc->hpe_hist_size ]; enc->hpe_hist_size = hist_size; enc->hpe_hist_idx = j % hist_size; enc->hpe_hist_wrapped = enc->hpe_hist_idx == 0; free(enc->hpe_hist_buf); enc->hpe_hist_buf = hist_buf; } /* Returns true if `nameval_hash' was already in history, false otherwise. */ static int henc_hist_add (struct lshpack_enc *enc, uint32_t nameval_hash) { unsigned last; uint32_t *p; if (enc->hpe_hist_wrapped) last = enc->hpe_hist_size; else last = enc->hpe_hist_idx; enc->hpe_hist_buf[ last ] = nameval_hash; for (p = enc->hpe_hist_buf; *p != nameval_hash; ++p) ; enc->hpe_hist_buf[ enc->hpe_hist_idx ] = nameval_hash; enc->hpe_hist_idx = (enc->hpe_hist_idx + 1) % enc->hpe_hist_size; enc->hpe_hist_wrapped |= enc->hpe_hist_idx == 0; return p < enc->hpe_hist_buf + last; } unsigned char * lshpack_enc_encode (struct lshpack_enc *enc, unsigned char *dst, unsigned char *dst_end, lsxpack_header_t *input) { //indexed_type: 0, Add, 1,: without, 2: never static const char indexed_prefix_number[] = {0x40, 0x00, 0x10}; unsigned char *const dst_org = dst; int rc; int val_matched = 0; unsigned table_id; if (dst_end <= dst) return dst_org; if (input->flags & LSXPACK_HPACK_VAL_MATCHED) { assert(input->hpack_index != LSHPACK_HDR_UNKNOWN); assert(input->val_len == static_table[input->hpack_index - 1].val_len); assert(memcmp(lsxpack_header_get_value(input), static_table[input->hpack_index - 1].val, input->val_len) == 0); table_id = input->hpack_index; val_matched = 1; } else { if (input->flags & LSXPACK_NEVER_INDEX) input->indexed_type = 2; table_id = henc_find_table_id(enc, input, &val_matched); if (enc->hpe_hist_buf) { rc = henc_hist_add(enc, input->nameval_hash); if (!rc && enc->hpe_hist_wrapped && input->indexed_type == 0) input->indexed_type = 1; } } if (table_id > 0) { if (val_matched) { // LSXPACK_VAL_MATCHED MUST NOT set for dynamic table // otherwise, it may cause trouble when feed the input to a different encoder. if (table_id > HPACK_STATIC_TABLE_SIZE) assert(!(input->flags & LSXPACK_HPACK_VAL_MATCHED)); *dst = 0x80; dst = lshpack_enc_enc_int(dst, dst_end, table_id, 7); /* No need to check return value: we pass it up as-is because * the behavior is the same. */ return dst; } else { *dst = indexed_prefix_number[input->indexed_type]; dst = lshpack_enc_enc_int(dst, dst_end, table_id, ((input->indexed_type == 0) ? 6 : 4)); if (dst == dst_org) return dst_org; } } else { assert(input->name_len > 0); *dst++ = indexed_prefix_number[input->indexed_type]; rc = lshpack_enc_enc_str(dst, dst_end - dst, (unsigned char *)lsxpack_header_get_name(input), input->name_len); if (rc < 0) return dst_org; //Failed to enc this header, return unchanged ptr. dst += rc; } rc = lshpack_enc_enc_str(dst, dst_end - dst, (const unsigned char *)input->buf + input->val_offset, input->val_len); if (rc < 0) return dst_org; //Failed to enc this header, return unchanged ptr. dst += rc; if (input->indexed_type == 0) { rc = lshpack_enc_push_entry(enc, input); if (rc != 0) return dst_org; //Failed to enc this header, return unchanged ptr. } return dst; } void lshpack_enc_set_max_capacity (struct lshpack_enc *enc, unsigned max_capacity) { enc->hpe_max_capacity = max_capacity; henc_remove_overflow_entries(enc); if (lshpack_enc_hist_used(enc)) henc_resize_history(enc); } #if LS_HPACK_EMIT_TEST_CODE void lshpack_enc_iter_init (struct lshpack_enc *enc, void **iter) { *iter = STAILQ_FIRST(&enc->hpe_all_entries); } /* Returns 0 if entry is found */ int lshpack_enc_iter_next (struct lshpack_enc *enc, void **iter, struct enc_dyn_table_entry *retval) { const struct lshpack_enc_table_entry *entry; entry = *iter; if (!entry) return -1; *iter = STAILQ_NEXT(entry, ete_next_all); retval->name = ETE_NAME(entry); retval->value = ETE_VALUE(entry); retval->name_len = entry->ete_name_len; retval->value_len = entry->ete_val_len; retval->entry_id = henc_calc_table_id(enc, entry); return 0; } #endif /* Dynamic table entry: */ struct dec_table_entry { unsigned dte_name_len; unsigned dte_val_len; #if LSHPACK_DEC_CALC_HASH uint32_t dte_name_hash; uint32_t dte_nameval_hash; enum { DTEF_NAME_HASH = LSXPACK_NAME_HASH, DTEF_NAMEVAL_HASH = LSXPACK_NAMEVAL_HASH, } dte_flags:8; #endif uint8_t dte_name_idx; char dte_buf[]; /* Contains both name and value */ }; #define DTE_NAME(dte) ((dte)->dte_buf) #define DTE_VALUE(dte) (&(dte)->dte_buf[(dte)->dte_name_len]) enum { HPACK_HUFFMAN_FLAG_ACCEPTED = 0x01, HPACK_HUFFMAN_FLAG_SYM = 0x02, HPACK_HUFFMAN_FLAG_FAIL = 0x04, }; struct decode_status { uint8_t state; uint8_t eos; }; void lshpack_dec_init (struct lshpack_dec *dec) { memset(dec, 0, sizeof(*dec)); dec->hpd_max_capacity = INITIAL_DYNAMIC_TABLE_SIZE; dec->hpd_cur_max_capacity = INITIAL_DYNAMIC_TABLE_SIZE; lshpack_arr_init(&dec->hpd_dyn_table); } void lshpack_dec_cleanup (struct lshpack_dec *dec) { uintptr_t val; while (lshpack_arr_count(&dec->hpd_dyn_table) > 0) { val = lshpack_arr_pop(&dec->hpd_dyn_table); free((struct dec_table_entry *) val); } lshpack_arr_cleanup(&dec->hpd_dyn_table); } /* Maximum number of bytes required to encode a 32-bit integer */ #define LSHPACK_UINT32_ENC_SZ 6 /* Assumption: we have at least one byte to work with */ #if !LS_HPACK_EMIT_TEST_CODE static #endif int lshpack_dec_dec_int (const unsigned char **src_p, const unsigned char *src_end, unsigned prefix_bits, uint32_t *value_p) { const unsigned char *const orig_src = *src_p; const unsigned char *src; unsigned prefix_max, M; uint32_t val, B; src = *src_p; prefix_max = (1 << prefix_bits) - 1; val = *src++; val &= prefix_max; if (val < prefix_max) { *src_p = src; *value_p = val; return 0; } M = 0; do { if (src < src_end) { B = *src++; val = val + ((B & 0x7f) << M); M += 7; } else if (src - orig_src < LSHPACK_UINT32_ENC_SZ) return -1; else return -2; } while (B & 0x80); if (M <= 28 || (M == 35 && src[-1] <= 0xF && val - (src[-1] << 28) < val)) { *src_p = src; *value_p = val; return 0; } else return -2; } static void hdec_drop_oldest_entry (struct lshpack_dec *dec) { struct dec_table_entry *entry; entry = (void *) lshpack_arr_shift(&dec->hpd_dyn_table); dec->hpd_cur_capacity -= DYNAMIC_ENTRY_OVERHEAD + entry->dte_name_len + entry->dte_val_len; ++dec->hpd_state; free(entry); } static void hdec_remove_overflow_entries (struct lshpack_dec *dec) { while (dec->hpd_cur_capacity > dec->hpd_cur_max_capacity) hdec_drop_oldest_entry(dec); } static void hdec_update_max_capacity (struct lshpack_dec *dec, uint32_t new_capacity) { dec->hpd_cur_max_capacity = new_capacity; hdec_remove_overflow_entries(dec); } void lshpack_dec_set_max_capacity (struct lshpack_dec *dec, unsigned max_capacity) { dec->hpd_max_capacity = max_capacity; hdec_update_max_capacity(dec, max_capacity); } static unsigned char * hdec_huff_dec4bits (uint8_t src_4bits, unsigned char *dst, struct decode_status *status) { const struct decode_el cur_dec_code = decode_tables[status->state][src_4bits]; if (cur_dec_code.flags & HPACK_HUFFMAN_FLAG_FAIL) { return NULL; //failed } if (cur_dec_code.flags & HPACK_HUFFMAN_FLAG_SYM) { *dst = cur_dec_code.sym; dst++; } status->state = cur_dec_code.state; status->eos = ((cur_dec_code.flags & HPACK_HUFFMAN_FLAG_ACCEPTED) != 0); return dst; } #if !LS_HPACK_USE_LARGE_TABLES #define lshpack_dec_huff_decode_full lshpack_dec_huff_decode #endif int lshpack_dec_huff_decode_full (const unsigned char *src, int src_len, unsigned char *dst, int dst_len) { const unsigned char *p_src = src; const unsigned char *const src_end = src + src_len; unsigned char *p_dst = dst; unsigned char *dst_end = dst + dst_len; struct decode_status status = { 0, 1 }; while (p_src != src_end) { if (p_dst == dst_end) return LSHPACK_ERR_MORE_BUF; if ((p_dst = hdec_huff_dec4bits(*p_src >> 4, p_dst, &status)) == NULL) return -1; if (p_dst == dst_end) return LSHPACK_ERR_MORE_BUF; if ((p_dst = hdec_huff_dec4bits(*p_src & 0xf, p_dst, &status)) == NULL) return -1; ++p_src; } if (!status.eos) return -1; return p_dst - dst; } int lshpack_dec_huff_decode (const unsigned char *src, int src_len, unsigned char *dst, int dst_len); //reutrn the length in the dst, also update the src #if !LS_HPACK_EMIT_TEST_CODE static #endif int hdec_dec_str (unsigned char *dst, size_t dst_len, const unsigned char **src, const unsigned char *src_end) { if ((*src) == src_end) return 0; int is_huffman = (*(*src) & 0x80); uint32_t len; if (0 != lshpack_dec_dec_int(src, src_end, 7, &len)) return LSHPACK_ERR_BAD_DATA; //wrong int int ret = 0; if ((uint32_t)(src_end - (*src)) < len) { return LSHPACK_ERR_BAD_DATA; //wrong int } if (is_huffman) { ret = lshpack_dec_huff_decode(*src, len, dst, dst_len); if (ret < 0) return ret; //Wrong code (*src) += len; } else { if (dst_len < len) { ret = dst_len - len; if (ret > LSHPACK_ERR_MORE_BUF) ret = LSHPACK_ERR_MORE_BUF; //dst not enough space } else { memcpy(dst, (*src), len); (*src) += len; ret = len; } } return ret; } /* hpd_dyn_table is a dynamic array. New entries are pushed onto it, * while old entries are shifted from it. */ static struct dec_table_entry * hdec_get_table_entry (struct lshpack_dec *dec, uint32_t index) { uintptr_t val; index -= HPACK_STATIC_TABLE_SIZE; if (index == 0 || index > lshpack_arr_count(&dec->hpd_dyn_table)) return NULL; index = lshpack_arr_count(&dec->hpd_dyn_table) - index; val = lshpack_arr_get(&dec->hpd_dyn_table, index); return (struct dec_table_entry *) val; } #if !LS_HPACK_EMIT_TEST_CODE static #endif int lshpack_dec_push_entry (struct lshpack_dec *dec, const struct lsxpack_header *xhdr) { struct dec_table_entry *entry; unsigned name_len, val_len; size_t size; name_len = xhdr->name_len; val_len = xhdr->val_len; size = sizeof(*entry) + name_len + val_len; entry = malloc(size); if (!entry) return -1; if (0 != lshpack_arr_push(&dec->hpd_dyn_table, (uintptr_t) entry)) { free(entry); return -1; } ++dec->hpd_state; dec->hpd_cur_capacity += DYNAMIC_ENTRY_OVERHEAD + name_len + val_len; entry->dte_name_len = name_len; entry->dte_val_len = val_len; entry->dte_name_idx = xhdr->hpack_index; #if LSHPACK_DEC_CALC_HASH entry->dte_flags = xhdr->flags & (LSXPACK_NAME_HASH|LSXPACK_NAMEVAL_HASH); entry->dte_name_hash = xhdr->name_hash; entry->dte_nameval_hash = xhdr->nameval_hash; #endif memcpy(DTE_NAME(entry), lsxpack_header_get_name(xhdr), name_len); memcpy(DTE_VALUE(entry), lsxpack_header_get_value(xhdr), val_len); hdec_remove_overflow_entries(dec); return 0; } static int lshpack_dec_copy_value (lsxpack_header_t *output, char *dest, const char *val, unsigned val_len) { if (val_len + LSHPACK_DEC_HTTP1X_EXTRA > (unsigned)output->val_len) return LSHPACK_ERR_MORE_BUF; output->val_offset = output->name_offset + output->name_len + LSHPACK_DEC_HTTP1X_EXTRA; assert(dest == output->buf + output->val_offset); output->val_len = val_len; memcpy(dest, val, output->val_len); dest += output->val_len; #if LSHPACK_DEC_HTTP1X_OUTPUT *dest++ = '\r'; *dest++ = '\n'; #endif return 0; } static int lshpack_dec_copy_name (lsxpack_header_t *output, char **dest, const char *name, unsigned name_len) { if (name_len + LSHPACK_DEC_HTTP1X_EXTRA > (unsigned)output->val_len) return LSHPACK_ERR_MORE_BUF; output->val_len -= name_len + LSHPACK_DEC_HTTP1X_EXTRA; output->name_len = name_len; memcpy(*dest, name, name_len); *dest += name_len; #if LSHPACK_DEC_HTTP1X_OUTPUT *(*dest)++ = ':'; *(*dest)++ = ' '; #endif return 0; } enum { LSHPACK_ADD_INDEX = 0, LSHPACK_NO_INDEX = 1, LSHPACK_NEVER_INDEX = 2, LSHPACK_VAL_INDEX = 3, }; int lshpack_dec_decode (struct lshpack_dec *dec, const unsigned char **src, const unsigned char *src_end, struct lsxpack_header *output) { struct dec_table_entry *entry; uint32_t index, new_capacity; int indexed_type, len; const unsigned char *s; size_t buf_len = output->val_len; size_t extra_buf = 0; if ((*src) == src_end) return LSHPACK_ERR_BAD_DATA; buf_len = output->val_len; extra_buf = 0; s = *src; while ((*s & 0xe0) == 0x20) //001 xxxxx { if (0 != lshpack_dec_dec_int(&s, src_end, 5, &new_capacity)) return LSHPACK_ERR_BAD_DATA; if (new_capacity > dec->hpd_max_capacity) return LSHPACK_ERR_BAD_DATA; hdec_update_max_capacity(dec, new_capacity); if (s == src_end) return LSHPACK_ERR_BAD_DATA; } /* lshpack_dec_dec_int() sets `index' and advances `src'. If we do not * call it, we set `index' and advance `src' ourselves: */ if (*s & 0x80) //1 xxxxxxx { if (0 != lshpack_dec_dec_int(&s, src_end, 7, &index)) return LSHPACK_ERR_BAD_DATA; if (index == 0) return LSHPACK_ERR_BAD_DATA; indexed_type = LSHPACK_VAL_INDEX; //need to parse value } else if (*s > 0x40) //01 xxxxxx { if (0 != lshpack_dec_dec_int(&s, src_end, 6, &index)) return LSHPACK_ERR_BAD_DATA; indexed_type = LSHPACK_ADD_INDEX; } else if (*s == 0x40) //custmized //0100 0000 { indexed_type = LSHPACK_ADD_INDEX; index = LSHPACK_HDR_UNKNOWN; ++s; } //Never indexed else if (*s == 0x10) //00010000 { indexed_type = LSHPACK_NEVER_INDEX; output->flags |= LSXPACK_NEVER_INDEX; index = LSHPACK_HDR_UNKNOWN; ++s; } else if ((*s & 0xf0) == 0x10) //0001 xxxx { if (0 != lshpack_dec_dec_int(&s, src_end, 4, &index)) return LSHPACK_ERR_BAD_DATA; indexed_type = LSHPACK_NEVER_INDEX; output->flags |= LSXPACK_NEVER_INDEX; } //without indexed else if (*s == 0x00) //0000 0000 { indexed_type = LSHPACK_NO_INDEX; index = LSHPACK_HDR_UNKNOWN; ++s; } else // 0000 xxxx { if (0 != lshpack_dec_dec_int(&s, src_end, 4, &index)) return LSHPACK_ERR_BAD_DATA; indexed_type = LSHPACK_NO_INDEX; } if (index != LSHPACK_HDR_UNKNOWN && index <= LSHPACK_HDR_WWW_AUTHENTICATE) { output->hpack_index = index; } char *name = output->buf + output->name_offset; if (index > 0) { if (index <= HPACK_STATIC_TABLE_SIZE) //static table { if (lshpack_dec_copy_name(output, &name, static_table[index - 1].name, static_table[index - 1].name_len) == LSHPACK_ERR_MORE_BUF) { extra_buf = static_table[index - 1].name_len + LSHPACK_DEC_HTTP1X_EXTRA; goto need_more_buf; } output->flags |= LSXPACK_NAME_HASH; output->name_hash = static_table_name_hash[index - 1]; if (indexed_type == LSHPACK_VAL_INDEX) { if (lshpack_dec_copy_value(output, name, static_table[index - 1].val, static_table[index - 1].val_len) == 0) { output->flags |= LSXPACK_NAMEVAL_HASH; output->nameval_hash = static_table_nameval_hash[index - 1]; goto decode_end; } else { extra_buf = static_table[index - 1].val_len + LSHPACK_DEC_HTTP1X_EXTRA; goto need_more_buf; } } } else { entry = hdec_get_table_entry(dec, index); if (entry == NULL) return LSHPACK_ERR_BAD_DATA; if (lshpack_dec_copy_name(output, &name, DTE_NAME(entry), entry->dte_name_len) == LSHPACK_ERR_MORE_BUF) { extra_buf = entry->dte_name_len + LSHPACK_DEC_HTTP1X_EXTRA; goto need_more_buf; } if (entry->dte_name_idx) output->hpack_index = entry->dte_name_idx; else output->hpack_index = LSHPACK_HDR_UNKNOWN; #if LSHPACK_DEC_CALC_HASH output->flags |= entry->dte_flags & DTEF_NAME_HASH; output->name_hash = entry->dte_name_hash; #endif if (indexed_type == LSHPACK_VAL_INDEX) { if (lshpack_dec_copy_value(output, name, DTE_VALUE(entry), entry->dte_val_len) == 0) { #if LSHPACK_DEC_CALC_HASH output->flags |= entry->dte_flags & DTEF_NAMEVAL_HASH; output->nameval_hash = entry->dte_nameval_hash; #endif goto decode_end; } else { extra_buf = entry->dte_val_len + LSHPACK_DEC_HTTP1X_EXTRA; goto need_more_buf; } } } } else { len = hdec_dec_str((unsigned char *)name, output->val_len, &s, src_end); if (len < 0) { if (len <= LSHPACK_ERR_MORE_BUF) { extra_buf = -len; goto need_more_buf; } return len; //error } if (len > UINT16_MAX) return LSHPACK_ERR_TOO_LARGE; #if LSHPACK_DEC_CALC_HASH output->flags |= LSXPACK_NAME_HASH; output->name_hash = XXH32(name, (size_t) len, LSHPACK_XXH_SEED); #endif output->name_len = len; name += output->name_len; #if LSHPACK_DEC_HTTP1X_OUTPUT if (output->name_len + 2 <= output->val_len) { *name++ = ':'; *name++ = ' '; } else { extra_buf = 2; goto need_more_buf; } #endif output->val_len -= len + LSHPACK_DEC_HTTP1X_EXTRA; } len = hdec_dec_str((unsigned char *)name, output->val_len, &s, src_end); if (len < 0) { if (len <= LSHPACK_ERR_MORE_BUF) { extra_buf = -len; goto need_more_buf; } return len; //error } if (len > UINT16_MAX) return LSHPACK_ERR_TOO_LARGE; #if LSHPACK_DEC_CALC_HASH assert(output->flags & LSXPACK_NAME_HASH); output->flags |= LSXPACK_NAMEVAL_HASH; output->nameval_hash = XXH32(name, (size_t) len, output->name_hash); #endif #if LSHPACK_DEC_HTTP1X_OUTPUT if ((unsigned) len + 2 <= output->val_len) memcpy(name + len, "\r\n", 2); else { extra_buf = 2; goto need_more_buf; } #endif output->val_offset = output->name_offset + output->name_len + LSHPACK_DEC_HTTP1X_EXTRA; output->val_len = len; if (indexed_type == LSHPACK_ADD_INDEX && 0 != lshpack_dec_push_entry(dec, output)) return LSHPACK_ERR_BAD_DATA; //error decode_end: *src = s; #if LSHPACK_DEC_HTTP1X_OUTPUT output->dec_overhead = 4; #endif return 0; need_more_buf: buf_len += extra_buf; output->val_len = buf_len; return LSHPACK_ERR_MORE_BUF; } #if LS_HPACK_USE_LARGE_TABLES #define SHORTEST_CODE 5 /* The decoder is optimized for the common case. Most of the time, we decode * data whose encoding is 16 bits or shorter. This lets us use a 64 KB table * indexed by two bytes of input and outputs 1, 2, or 3 bytes at a time. * * In the case a longer code is encoutered, we fall back to the original * Huffman decoder that supports all code lengths. */ int lshpack_dec_huff_decode (const unsigned char *src, int src_len, unsigned char *dst, int dst_len) { unsigned char *const orig_dst = dst; const unsigned char *const src_end = src + src_len; unsigned char *const dst_end = dst + dst_len; uintptr_t buf; /* OK not to initialize the buffer */ unsigned avail_bits, len; struct hdec hdec; uint16_t idx; int r; #if __GNUC__ #pragma GCC diagnostic push #pragma GCC diagnostic ignored "-Wmaybe-uninitialized" #pragma GCC diagnostic ignored "-Wuninitialized" #else buf = 0; #endif avail_bits = 0; while (1) { if (src + sizeof(buf) <= src_end) { len = (sizeof(buf) * 8 - avail_bits) >> 3; avail_bits += len << 3; switch (len) { #if UINTPTR_MAX == 18446744073709551615ull case 8: buf <<= 8; buf |= (uintptr_t) *src++; /* fall through */ case 7: buf <<= 8; buf |= (uintptr_t) *src++; /* fall through */ default: buf <<= 48; buf |= (uintptr_t) *src++ << 40; buf |= (uintptr_t) *src++ << 32; buf |= (uintptr_t) *src++ << 24; buf |= (uintptr_t) *src++ << 16; #else /* fall through */ case 4: buf <<= 8; buf |= (uintptr_t) *src++; /* fall through */ case 3: buf <<= 8; buf |= (uintptr_t) *src++; /* fall through */ default: buf <<= 16; #endif buf |= (uintptr_t) *src++ << 8; buf |= (uintptr_t) *src++ << 0; } } else if (src < src_end) do { buf <<= 8; buf |= (uintptr_t) *src++; avail_bits += 8; } while (src < src_end && avail_bits <= sizeof(buf) * 8 - 8); else break; /* Normal case terminating condition: out of input */ if (dst_end - dst >= (ptrdiff_t) (8 * sizeof(buf) / SHORTEST_CODE) && avail_bits >= 16) { /* Fast path: don't check destination bounds */ do { idx = buf >> (avail_bits - 16); hdec = hdecs[idx]; dst[0] = hdec.out[0]; dst[1] = hdec.out[1]; dst[2] = hdec.out[2]; dst += hdec.lens & 3; avail_bits -= hdec.lens >> 2; } while (avail_bits >= 16 && hdec.lens); if (avail_bits < 16) continue; goto slow_path; } else while (avail_bits >= 16) { idx = buf >> (avail_bits - 16); hdec = hdecs[idx]; len = hdec.lens & 3; if (len && dst + len <= dst_end) { switch (len) { case 3: *dst++ = hdec.out[0]; *dst++ = hdec.out[1]; *dst++ = hdec.out[2]; break; case 2: *dst++ = hdec.out[0]; *dst++ = hdec.out[1]; break; default: *dst++ = hdec.out[0]; break; } avail_bits -= hdec.lens >> 2; } else if (dst + len > dst_end) { r = dst_end - dst - len; if (r > LSHPACK_ERR_MORE_BUF) r = LSHPACK_ERR_MORE_BUF; return r; } else goto slow_path; } } if (avail_bits >= SHORTEST_CODE) { idx = buf << (16 - avail_bits); idx |= (1 << (16 - avail_bits)) - 1; /* EOF */ if (idx == 0xFFFF && avail_bits < 8) goto end; /* If a byte or more of input is left, this mean there is a valid * encoding, not just EOF. */ hdec = hdecs[idx]; len = hdec.lens & 3; if (((unsigned) hdec.lens >> 2) > avail_bits) return -1; if (len && dst + len <= dst_end) { switch (len) { case 3: *dst++ = hdec.out[0]; *dst++ = hdec.out[1]; *dst++ = hdec.out[2]; break; case 2: *dst++ = hdec.out[0]; *dst++ = hdec.out[1]; break; default: *dst++ = hdec.out[0]; break; } avail_bits -= hdec.lens >> 2; } else if (dst + len > dst_end) { r = dst_end - dst - len; if (r > LSHPACK_ERR_MORE_BUF) r = LSHPACK_ERR_MORE_BUF; return r; } else /* This must be an invalid code, otherwise it would have fit */ return -1; } if (avail_bits > 0) { if (((1u << avail_bits) - 1) != (buf & ((1u << avail_bits) - 1))) return -1; /* Not EOF as expected */ } #if __GNUC__ #pragma GCC diagnostic pop #endif end: return dst - orig_dst; slow_path: /* Find previous byte boundary and finish decoding thence. */ while ((avail_bits & 7) && dst > orig_dst) avail_bits += encode_table[ *--dst ].bits; assert((avail_bits & 7) == 0); src -= avail_bits >> 3; r = lshpack_dec_huff_decode_full(src, src_end - src, dst, dst_end - dst); if (r >= 0) return dst - orig_dst + r; else return r; } #endif #if __GNUC__ #pragma GCC diagnostic pop /* -Wunknown-pragmas */ #endif