1 /*
2 * nghttp2 - HTTP/2 C Library
3 *
4 * Copyright (c) 2012 Tatsuhiro Tsujikawa
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining
7 * a copy of this software and associated documentation files (the
8 * "Software"), to deal in the Software without restriction, including
9 * without limitation the rights to use, copy, modify, merge, publish,
10 * distribute, sublicense, and/or sell copies of the Software, and to
11 * permit persons to whom the Software is furnished to do so, subject to
12 * the following conditions:
13 *
14 * The above copyright notice and this permission notice shall be
15 * included in all copies or substantial portions of the Software.
16 *
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
18 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
19 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
20 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
21 * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
22 * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
23 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
24 */
25 #include "nghttp2_npn.h"
26
27 #include <string.h>
28
select_next_protocol(unsigned char ** out,unsigned char * outlen,const unsigned char * in,unsigned int inlen,const char * key,unsigned int keylen)29 static int select_next_protocol(unsigned char **out, unsigned char *outlen,
30 const unsigned char *in, unsigned int inlen,
31 const char *key, unsigned int keylen) {
32 unsigned int i;
33 for (i = 0; i + keylen <= inlen; i += (unsigned int)(in[i] + 1)) {
34 if (memcmp(&in[i], key, keylen) == 0) {
35 *out = (unsigned char *)&in[i + 1];
36 *outlen = in[i];
37 return 0;
38 }
39 }
40 return -1;
41 }
42
43 #define NGHTTP2_HTTP_1_1_ALPN "\x8http/1.1"
44 #define NGHTTP2_HTTP_1_1_ALPN_LEN (sizeof(NGHTTP2_HTTP_1_1_ALPN) - 1)
45
nghttp2_select_next_protocol(unsigned char ** out,unsigned char * outlen,const unsigned char * in,unsigned int inlen)46 int nghttp2_select_next_protocol(unsigned char **out, unsigned char *outlen,
47 const unsigned char *in, unsigned int inlen) {
48 if (select_next_protocol(out, outlen, in, inlen, NGHTTP2_PROTO_ALPN,
49 NGHTTP2_PROTO_ALPN_LEN) == 0) {
50 return 1;
51 }
52 if (select_next_protocol(out, outlen, in, inlen, NGHTTP2_HTTP_1_1_ALPN,
53 NGHTTP2_HTTP_1_1_ALPN_LEN) == 0) {
54 return 0;
55 }
56 return -1;
57 }
58