1
2 /*
3 * Copyright (C) NGINX, Inc.
4 */
5
6 #include <nxt_main.h>
7 #include <nxt_websocket.h>
8 #include <nxt_sha1.h>
9
10
11 static void
nxt_websocket_base64_encode(u_char * d,const uint8_t * s,size_t len)12 nxt_websocket_base64_encode(u_char *d, const uint8_t *s, size_t len)
13 {
14 u_char c0, c1, c2;
15 static const u_char basis[] =
16 "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
17
18 while (len > 2) {
19 c0 = s[0];
20 c1 = s[1];
21 c2 = s[2];
22
23 *d++ = basis[c0 >> 2];
24 *d++ = basis[((c0 & 0x03) << 4) | (c1 >> 4)];
25 *d++ = basis[((c1 & 0x0f) << 2) | (c2 >> 6)];
26 *d++ = basis[c2 & 0x3f];
27
28 s += 3;
29 len -= 3;
30 }
31
32 if (len > 0) {
33 c0 = s[0];
34 *d++ = basis[c0 >> 2];
35
36 if (len == 1) {
37 *d++ = basis[(c0 & 0x03) << 4];
38 *d++ = '=';
39 *d++ = '=';
40
41 } else {
42 c1 = s[1];
43
44 *d++ = basis[((c0 & 0x03) << 4) | (c1 >> 4)];
45 *d++ = basis[(c1 & 0x0f) << 2];
46
47 *d++ = '=';
48 }
49 }
50 }
51
52
53 void
nxt_websocket_accept(u_char * accept,const void * key)54 nxt_websocket_accept(u_char *accept, const void *key)
55 {
56 u_char bin_accept[20];
57 nxt_sha1_t ctx;
58 static const char accept_guid[] = "258EAFA5-E914-47DA-95CA-C5AB0DC85B11";
59
60 nxt_sha1_init(&ctx);
61 nxt_sha1_update(&ctx, key, 24);
62 nxt_sha1_update(&ctx, accept_guid, nxt_length(accept_guid));
63 nxt_sha1_final(bin_accept, &ctx);
64
65 nxt_websocket_base64_encode(accept, bin_accept, sizeof(bin_accept));
66 }
67
68
69