From 328ad0a41c6bdf596224ff2e9ab9c0fabde8634d Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 28 Apr 2024 09:32:08 +0200 Subject: Adding upstream version 0.8.0. Signed-off-by: Daniel Baumann --- lib/nghttp3_qpack_huffman.c | 122 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 122 insertions(+) create mode 100644 lib/nghttp3_qpack_huffman.c (limited to 'lib/nghttp3_qpack_huffman.c') diff --git a/lib/nghttp3_qpack_huffman.c b/lib/nghttp3_qpack_huffman.c new file mode 100644 index 0000000..c36a68e --- /dev/null +++ b/lib/nghttp3_qpack_huffman.c @@ -0,0 +1,122 @@ +/* + * nghttp3 + * + * Copyright (c) 2019 nghttp3 contributors + * Copyright (c) 2013 nghttp2 contributors + * + * 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 "nghttp3_qpack_huffman.h" + +#include +#include +#include + +#include "nghttp3_conv.h" + +size_t nghttp3_qpack_huffman_encode_count(const uint8_t *src, size_t len) { + size_t i; + size_t nbits = 0; + + for (i = 0; i < len; ++i) { + nbits += huffman_sym_table[src[i]].nbits; + } + /* pad the prefix of EOS (256) */ + return (nbits + 7) / 8; +} + +uint8_t *nghttp3_qpack_huffman_encode(uint8_t *dest, const uint8_t *src, + size_t srclen) { + const nghttp3_qpack_huffman_sym *sym; + const uint8_t *end = src + srclen; + uint64_t code = 0; + size_t nbits = 0; + uint32_t x; + + for (; src != end;) { + sym = &huffman_sym_table[*src++]; + code |= (uint64_t)sym->code << (32 - nbits); + nbits += sym->nbits; + if (nbits < 32) { + continue; + } + x = htonl((uint32_t)(code >> 32)); + memcpy(dest, &x, 4); + dest += 4; + code <<= 32; + nbits -= 32; + } + + for (; nbits >= 8;) { + *dest++ = (uint8_t)(code >> 56); + code <<= 8; + nbits -= 8; + } + + if (nbits) { + *dest++ = (uint8_t)((uint8_t)(code >> 56) | ((1 << (8 - nbits)) - 1)); + } + + return dest; +} + +void nghttp3_qpack_huffman_decode_context_init( + nghttp3_qpack_huffman_decode_context *ctx) { + ctx->fstate = NGHTTP3_QPACK_HUFFMAN_ACCEPTED; +} + +nghttp3_ssize +nghttp3_qpack_huffman_decode(nghttp3_qpack_huffman_decode_context *ctx, + uint8_t *dest, const uint8_t *src, size_t srclen, + int fin) { + uint8_t *p = dest; + const uint8_t *end = src + srclen; + nghttp3_qpack_huffman_decode_node node = {ctx->fstate, 0}; + const nghttp3_qpack_huffman_decode_node *t = &node; + uint8_t c; + + /* We use the decoding algorithm described in + http://graphics.ics.uci.edu/pub/Prefix.pdf */ + for (; src != end;) { + c = *src++; + t = &qpack_huffman_decode_table[t->fstate & 0x1ff][c >> 4]; + if (t->fstate & NGHTTP3_QPACK_HUFFMAN_SYM) { + *p++ = t->sym; + } + + t = &qpack_huffman_decode_table[t->fstate & 0x1ff][c & 0xf]; + if (t->fstate & NGHTTP3_QPACK_HUFFMAN_SYM) { + *p++ = t->sym; + } + } + + ctx->fstate = t->fstate; + + if (fin && !(ctx->fstate & NGHTTP3_QPACK_HUFFMAN_ACCEPTED)) { + return NGHTTP3_ERR_QPACK_FATAL; + } + + return p - dest; +} + +int nghttp3_qpack_huffman_decode_failure_state( + nghttp3_qpack_huffman_decode_context *ctx) { + return ctx->fstate == 0x100; +} -- cgit v1.2.3