From afea5f9539cbf1eeaa85ec77d79eb2f59724f470 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 28 Apr 2024 09:34:15 +0200 Subject: Adding upstream version 1.52.0. Signed-off-by: Daniel Baumann --- lib/nghttp2_hd_huffman.c | 144 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 144 insertions(+) create mode 100644 lib/nghttp2_hd_huffman.c (limited to 'lib/nghttp2_hd_huffman.c') diff --git a/lib/nghttp2_hd_huffman.c b/lib/nghttp2_hd_huffman.c new file mode 100644 index 0000000..ac90f49 --- /dev/null +++ b/lib/nghttp2_hd_huffman.c @@ -0,0 +1,144 @@ +/* + * nghttp2 - HTTP/2 C Library + * + * Copyright (c) 2013 Tatsuhiro Tsujikawa + * + * 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 "nghttp2_hd_huffman.h" + +#include +#include +#include + +#include "nghttp2_hd.h" +#include "nghttp2_net.h" + +size_t nghttp2_hd_huff_encode_count(const uint8_t *src, size_t len) { + size_t i; + size_t nbits = 0; + + for (i = 0; i < len; ++i) { + nbits += huff_sym_table[src[i]].nbits; + } + /* pad the prefix of EOS (256) */ + return (nbits + 7) / 8; +} + +int nghttp2_hd_huff_encode(nghttp2_bufs *bufs, const uint8_t *src, + size_t srclen) { + const nghttp2_huff_sym *sym; + const uint8_t *end = src + srclen; + uint64_t code = 0; + uint32_t x; + size_t nbits = 0; + size_t avail; + int rv; + + avail = nghttp2_bufs_cur_avail(bufs); + + for (; src != end;) { + sym = &huff_sym_table[*src++]; + code |= (uint64_t)sym->code << (32 - nbits); + nbits += sym->nbits; + if (nbits < 32) { + continue; + } + if (avail >= 4) { + x = htonl((uint32_t)(code >> 32)); + memcpy(bufs->cur->buf.last, &x, 4); + bufs->cur->buf.last += 4; + avail -= 4; + code <<= 32; + nbits -= 32; + continue; + } + + for (; nbits >= 8;) { + rv = nghttp2_bufs_addb(bufs, (uint8_t)(code >> 56)); + if (rv != 0) { + return rv; + } + code <<= 8; + nbits -= 8; + } + + avail = nghttp2_bufs_cur_avail(bufs); + } + + for (; nbits >= 8;) { + rv = nghttp2_bufs_addb(bufs, (uint8_t)(code >> 56)); + if (rv != 0) { + return rv; + } + code <<= 8; + nbits -= 8; + } + + if (nbits) { + rv = nghttp2_bufs_addb( + bufs, (uint8_t)((uint8_t)(code >> 56) | ((1 << (8 - nbits)) - 1))); + if (rv != 0) { + return rv; + } + } + + return 0; +} + +void nghttp2_hd_huff_decode_context_init(nghttp2_hd_huff_decode_context *ctx) { + ctx->fstate = NGHTTP2_HUFF_ACCEPTED; +} + +ssize_t nghttp2_hd_huff_decode(nghttp2_hd_huff_decode_context *ctx, + nghttp2_buf *buf, const uint8_t *src, + size_t srclen, int final) { + const uint8_t *end = src + srclen; + nghttp2_huff_decode node = {ctx->fstate, 0}; + const nghttp2_huff_decode *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 = &huff_decode_table[t->fstate & 0x1ff][c >> 4]; + if (t->fstate & NGHTTP2_HUFF_SYM) { + *buf->last++ = t->sym; + } + + t = &huff_decode_table[t->fstate & 0x1ff][c & 0xf]; + if (t->fstate & NGHTTP2_HUFF_SYM) { + *buf->last++ = t->sym; + } + } + + ctx->fstate = t->fstate; + + if (final && !(ctx->fstate & NGHTTP2_HUFF_ACCEPTED)) { + return NGHTTP2_ERR_HEADER_COMP; + } + + return (ssize_t)srclen; +} + +int nghttp2_hd_huff_decode_failure_state(nghttp2_hd_huff_decode_context *ctx) { + return ctx->fstate == 0x100; +} -- cgit v1.2.3