blob: 64cca7873d1d3046c625141506d604e4ffbeadd6 [file] [log] [blame]
/*
* HPACK decompressor (RFC7541)
*
* Copyright (C) 2014-2017 Willy Tarreau <willy@haproxy.org>
* Copyright (C) 2017 HAProxy Technologies
*
* 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 <inttypes.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <haproxy/hpack-enc.h>
#include <haproxy/http-hdr-t.h>
#include <import/ist.h>
/*
* HPACK encoding: these tables were generated using gen-enc.c
*/
/* encoding of stream of compressed headers. This stream is composed of series
* of <len:8b> <index:8b> <name:<len>*8b>.
*/
const char hpack_enc_stream[666] = {
/* 0: */ 0x03, 0x15, 0x61, 0x67, 0x65, 0x03, 0x3c, 0x76,
/* 8: */ 0x69, 0x61, 0x04, 0x21, 0x64, 0x61, 0x74, 0x65,
/* 16: */ 0x04, 0x26, 0x68, 0x6f, 0x73, 0x74, 0x04, 0x22,
/* 24: */ 0x65, 0x74, 0x61, 0x67, 0x04, 0x25, 0x66, 0x72,
/* 32: */ 0x6f, 0x6d, 0x04, 0x2d, 0x6c, 0x69, 0x6e, 0x6b,
/* 40: */ 0x04, 0x3b, 0x76, 0x61, 0x72, 0x79, 0x05, 0x04,
/* 48: */ 0x3a, 0x70, 0x61, 0x74, 0x68, 0x05, 0x16, 0x61,
/* 56: */ 0x6c, 0x6c, 0x6f, 0x77, 0x05, 0x32, 0x72, 0x61,
/* 64: */ 0x6e, 0x67, 0x65, 0x06, 0x13, 0x61, 0x63, 0x63,
/* 72: */ 0x65, 0x70, 0x74, 0x06, 0x36, 0x73, 0x65, 0x72,
/* 80: */ 0x76, 0x65, 0x72, 0x06, 0x20, 0x63, 0x6f, 0x6f,
/* 88: */ 0x6b, 0x69, 0x65, 0x06, 0x23, 0x65, 0x78, 0x70,
/* 96: */ 0x65, 0x63, 0x74, 0x07, 0x33, 0x72, 0x65, 0x66,
/* 104: */ 0x65, 0x72, 0x65, 0x72, 0x07, 0x24, 0x65, 0x78,
/* 112: */ 0x70, 0x69, 0x72, 0x65, 0x73, 0x07, 0x02, 0x3a,
/* 120: */ 0x6d, 0x65, 0x74, 0x68, 0x6f, 0x64, 0x07, 0x06,
/* 128: */ 0x3a, 0x73, 0x63, 0x68, 0x65, 0x6d, 0x65, 0x07,
/* 136: */ 0x08, 0x3a, 0x73, 0x74, 0x61, 0x74, 0x75, 0x73,
/* 144: */ 0x07, 0x34, 0x72, 0x65, 0x66, 0x72, 0x65, 0x73,
/* 152: */ 0x68, 0x08, 0x2e, 0x6c, 0x6f, 0x63, 0x61, 0x74,
/* 160: */ 0x69, 0x6f, 0x6e, 0x08, 0x27, 0x69, 0x66, 0x2d,
/* 168: */ 0x6d, 0x61, 0x74, 0x63, 0x68, 0x08, 0x2a, 0x69,
/* 176: */ 0x66, 0x2d, 0x72, 0x61, 0x6e, 0x67, 0x65, 0x0a,
/* 184: */ 0x3a, 0x75, 0x73, 0x65, 0x72, 0x2d, 0x61, 0x67,
/* 192: */ 0x65, 0x6e, 0x74, 0x0a, 0x37, 0x73, 0x65, 0x74,
/* 200: */ 0x2d, 0x63, 0x6f, 0x6f, 0x6b, 0x69, 0x65, 0x0a,
/* 208: */ 0x01, 0x3a, 0x61, 0x75, 0x74, 0x68, 0x6f, 0x72,
/* 216: */ 0x69, 0x74, 0x79, 0x0b, 0x35, 0x72, 0x65, 0x74,
/* 224: */ 0x72, 0x79, 0x2d, 0x61, 0x66, 0x74, 0x65, 0x72,
/* 232: */ 0x0c, 0x1f, 0x63, 0x6f, 0x6e, 0x74, 0x65, 0x6e,
/* 240: */ 0x74, 0x2d, 0x74, 0x79, 0x70, 0x65, 0x0c, 0x2f,
/* 248: */ 0x6d, 0x61, 0x78, 0x2d, 0x66, 0x6f, 0x72, 0x77,
/* 256: */ 0x61, 0x72, 0x64, 0x73, 0x0d, 0x18, 0x63, 0x61,
/* 264: */ 0x63, 0x68, 0x65, 0x2d, 0x63, 0x6f, 0x6e, 0x74,
/* 272: */ 0x72, 0x6f, 0x6c, 0x0d, 0x2c, 0x6c, 0x61, 0x73,
/* 280: */ 0x74, 0x2d, 0x6d, 0x6f, 0x64, 0x69, 0x66, 0x69,
/* 288: */ 0x65, 0x64, 0x0d, 0x12, 0x61, 0x63, 0x63, 0x65,
/* 296: */ 0x70, 0x74, 0x2d, 0x72, 0x61, 0x6e, 0x67, 0x65,
/* 304: */ 0x73, 0x0d, 0x29, 0x69, 0x66, 0x2d, 0x6e, 0x6f,
/* 312: */ 0x6e, 0x65, 0x2d, 0x6d, 0x61, 0x74, 0x63, 0x68,
/* 320: */ 0x0d, 0x17, 0x61, 0x75, 0x74, 0x68, 0x6f, 0x72,
/* 328: */ 0x69, 0x7a, 0x61, 0x74, 0x69, 0x6f, 0x6e, 0x0d,
/* 336: */ 0x1e, 0x63, 0x6f, 0x6e, 0x74, 0x65, 0x6e, 0x74,
/* 344: */ 0x2d, 0x72, 0x61, 0x6e, 0x67, 0x65, 0x0e, 0x1c,
/* 352: */ 0x63, 0x6f, 0x6e, 0x74, 0x65, 0x6e, 0x74, 0x2d,
/* 360: */ 0x6c, 0x65, 0x6e, 0x67, 0x74, 0x68, 0x0e, 0x0f,
/* 368: */ 0x61, 0x63, 0x63, 0x65, 0x70, 0x74, 0x2d, 0x63,
/* 376: */ 0x68, 0x61, 0x72, 0x73, 0x65, 0x74, 0x0f, 0x10,
/* 384: */ 0x61, 0x63, 0x63, 0x65, 0x70, 0x74, 0x2d, 0x65,
/* 392: */ 0x6e, 0x63, 0x6f, 0x64, 0x69, 0x6e, 0x67, 0x0f,
/* 400: */ 0x11, 0x61, 0x63, 0x63, 0x65, 0x70, 0x74, 0x2d,
/* 408: */ 0x6c, 0x61, 0x6e, 0x67, 0x75, 0x61, 0x67, 0x65,
/* 416: */ 0x10, 0x1a, 0x63, 0x6f, 0x6e, 0x74, 0x65, 0x6e,
/* 424: */ 0x74, 0x2d, 0x65, 0x6e, 0x63, 0x6f, 0x64, 0x69,
/* 432: */ 0x6e, 0x67, 0x10, 0x1b, 0x63, 0x6f, 0x6e, 0x74,
/* 440: */ 0x65, 0x6e, 0x74, 0x2d, 0x6c, 0x61, 0x6e, 0x67,
/* 448: */ 0x75, 0x61, 0x67, 0x65, 0x10, 0x1d, 0x63, 0x6f,
/* 456: */ 0x6e, 0x74, 0x65, 0x6e, 0x74, 0x2d, 0x6c, 0x6f,
/* 464: */ 0x63, 0x61, 0x74, 0x69, 0x6f, 0x6e, 0x10, 0x3d,
/* 472: */ 0x77, 0x77, 0x77, 0x2d, 0x61, 0x75, 0x74, 0x68,
/* 480: */ 0x65, 0x6e, 0x74, 0x69, 0x63, 0x61, 0x74, 0x65,
/* 488: */ 0x11, 0x39, 0x74, 0x72, 0x61, 0x6e, 0x73, 0x66,
/* 496: */ 0x65, 0x72, 0x2d, 0x65, 0x6e, 0x63, 0x6f, 0x64,
/* 504: */ 0x69, 0x6e, 0x67, 0x11, 0x28, 0x69, 0x66, 0x2d,
/* 512: */ 0x6d, 0x6f, 0x64, 0x69, 0x66, 0x69, 0x65, 0x64,
/* 520: */ 0x2d, 0x73, 0x69, 0x6e, 0x63, 0x65, 0x12, 0x30,
/* 528: */ 0x70, 0x72, 0x6f, 0x78, 0x79, 0x2d, 0x61, 0x75,
/* 536: */ 0x74, 0x68, 0x65, 0x6e, 0x74, 0x69, 0x63, 0x61,
/* 544: */ 0x74, 0x65, 0x13, 0x19, 0x63, 0x6f, 0x6e, 0x74,
/* 552: */ 0x65, 0x6e, 0x74, 0x2d, 0x64, 0x69, 0x73, 0x70,
/* 560: */ 0x6f, 0x73, 0x69, 0x74, 0x69, 0x6f, 0x6e, 0x13,
/* 568: */ 0x2b, 0x69, 0x66, 0x2d, 0x75, 0x6e, 0x6d, 0x6f,
/* 576: */ 0x64, 0x69, 0x66, 0x69, 0x65, 0x64, 0x2d, 0x73,
/* 584: */ 0x69, 0x6e, 0x63, 0x65, 0x13, 0x31, 0x70, 0x72,
/* 592: */ 0x6f, 0x78, 0x79, 0x2d, 0x61, 0x75, 0x74, 0x68,
/* 600: */ 0x6f, 0x72, 0x69, 0x7a, 0x61, 0x74, 0x69, 0x6f,
/* 608: */ 0x6e, 0x19, 0x38, 0x73, 0x74, 0x72, 0x69, 0x63,
/* 616: */ 0x74, 0x2d, 0x74, 0x72, 0x61, 0x6e, 0x73, 0x70,
/* 624: */ 0x6f, 0x72, 0x74, 0x2d, 0x73, 0x65, 0x63, 0x75,
/* 632: */ 0x72, 0x69, 0x74, 0x79, 0x1b, 0x14, 0x61, 0x63,
/* 640: */ 0x63, 0x65, 0x73, 0x73, 0x2d, 0x63, 0x6f, 0x6e,
/* 648: */ 0x74, 0x72, 0x6f, 0x6c, 0x2d, 0x61, 0x6c, 0x6c,
/* 656: */ 0x6f, 0x77, 0x2d, 0x6f, 0x72, 0x69, 0x67, 0x69,
/* 664: */ 0x6e, 0x00,
};
/* This points to the first position in table hpack_enc_stream[] of a header
* of the same length.
*/
const signed short hpack_pos_len[32] = {
/* 0: */ -1, -1, -1, 0, 10, 46, 67, 99,
/* 8: */ 153, -1, 183, 219, 232, 260, 350, 382,
/* 16: */ 416, 488, 526, 546, -1, -1, -1, -1,
/* 24: */ -1, 609, -1, 636, -1, -1, -1, -1,
};
/* Tries to encode header whose name is <n> and value <v> into the chunk <out>.
* Returns non-zero on success, 0 on failure (buffer full).
*/
int hpack_encode_header(struct buffer *out, const struct ist n,
const struct ist v)
{
int len = out->data;
int size = out->size;
int pos;
if (len >= size)
return 0;
/* look for the header field <n> in the static table */
if (n.len >= sizeof(hpack_pos_len) / sizeof(hpack_pos_len[0]))
goto make_literal;
pos = hpack_pos_len[n.len];
if (pos >= 0) {
/* At least one header field of this length exist */
do {
char idx;
pos++;
idx = hpack_enc_stream[pos++];
pos += n.len;
if (isteq(ist2(&hpack_enc_stream[pos - n.len], n.len), n)) {
/* emit literal with indexing (7541#6.2.1) :
* [ 0 | 1 | Index (6+) ]
*/
out->area[len++] = idx | 0x40;
goto emit_value;
}
} while ((unsigned char)hpack_enc_stream[pos] == n.len);
}
make_literal:
if (likely(n.len < 127 && len + 2 + n.len <= size)) {
out->area[len++] = 0x00; /* literal without indexing -- new name */
out->area[len++] = n.len; /* single-byte length encoding */
ist2bin(out->area + len, n);
len += n.len;
}
else if (hpack_len_to_bytes(n.len) &&
len + 1 + hpack_len_to_bytes(n.len) + n.len <= size) {
out->area[len++] = 0x00; /* literal without indexing -- new name */
len = hpack_encode_len(out->area, len, n.len);
ist2bin(out->area + len, n);
len += n.len;
}
else {
/* header field name too large for the buffer */
return 0;
}
emit_value:
/* copy literal header field value */
if (!hpack_len_to_bytes(v.len) ||
len + hpack_len_to_bytes(v.len) + v.len > size) {
/* header value too large for the buffer */
return 0;
}
len = hpack_encode_len(out->area, len, v.len);
memcpy(out->area + len, v.ptr, v.len);
len += v.len;
out->data = len;
return 1;
}