1 b42d807f 2023-09-02 op /*
  2 b42d807f 2023-09-02 op  * This is free and unencumbered software released into the public domain.
  3 b42d807f 2023-09-02 op  *
  4 b42d807f 2023-09-02 op  * Anyone is free to copy, modify, publish, use, compile, sell, or
  5 b42d807f 2023-09-02 op  * distribute this software, either in source code form or as a compiled
  6 b42d807f 2023-09-02 op  * binary, for any purpose, commercial or non-commercial, and by any
  7 b42d807f 2023-09-02 op  * means.
  8 b42d807f 2023-09-02 op  *
  9 b42d807f 2023-09-02 op  * In jurisdictions that recognize copyright laws, the author or authors
 10 b42d807f 2023-09-02 op  * of this software dedicate any and all copyright interest in the
 11 b42d807f 2023-09-02 op  * software to the public domain. We make this dedication for the benefit
 12 b42d807f 2023-09-02 op  * of the public at large and to the detriment of our heirs and
 13 b42d807f 2023-09-02 op  * successors. We intend this dedication to be an overt act of
 14 b42d807f 2023-09-02 op  * relinquishment in perpetuity of all present and future rights to this
 15 b42d807f 2023-09-02 op  * software under copyright law.
 16 b42d807f 2023-09-02 op  *
 17 b42d807f 2023-09-02 op  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 18 b42d807f 2023-09-02 op  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 19 b42d807f 2023-09-02 op  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
 20 b42d807f 2023-09-02 op  * IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR
 21 b42d807f 2023-09-02 op  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 22 b42d807f 2023-09-02 op  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 23 b42d807f 2023-09-02 op  * OTHER DEALINGS IN THE SOFTWARE.
 24 b42d807f 2023-09-02 op  */
 25 b42d807f 2023-09-02 op 
 26 b42d807f 2023-09-02 op #include "config.h"
 27 b42d807f 2023-09-02 op 
 28 b42d807f 2023-09-02 op #include <arpa/inet.h>
 29 b42d807f 2023-09-02 op #include <errno.h>
 30 b42d807f 2023-09-02 op #include <stdio.h>
 31 b42d807f 2023-09-02 op #include <stdint.h>
 32 b42d807f 2023-09-02 op #include <string.h>
 33 b42d807f 2023-09-02 op #include <sha1.h>
 34 b42d807f 2023-09-02 op 
 35 b42d807f 2023-09-02 op #include "bufio.h"
 36 b42d807f 2023-09-02 op #include "http.h"
 37 b42d807f 2023-09-02 op #include "ws.h"
 38 b42d807f 2023-09-02 op 
 39 b42d807f 2023-09-02 op #define WS_GUID	"258EAFA5-E914-47DA-95CA-C5AB0DC85B11"
 40 b42d807f 2023-09-02 op 
 41 b42d807f 2023-09-02 op static int
 42 b42d807f 2023-09-02 op tob64(unsigned char ch)
 43 b42d807f 2023-09-02 op {
 44 b42d807f 2023-09-02 op 	if (ch < 26)
 45 b42d807f 2023-09-02 op 		return ('A' + ch);
 46 b42d807f 2023-09-02 op 	ch -= 26;
 47 b42d807f 2023-09-02 op 	if (ch < 26)
 48 b42d807f 2023-09-02 op 		return ('a' + ch);
 49 b42d807f 2023-09-02 op 	ch -= 26;
 50 b42d807f 2023-09-02 op 	if (ch < 10)
 51 b42d807f 2023-09-02 op 		return ('0' + ch);
 52 b42d807f 2023-09-02 op 	ch -= 10;
 53 b42d807f 2023-09-02 op 	if (ch == 0)
 54 b42d807f 2023-09-02 op 		return ('+');
 55 b42d807f 2023-09-02 op 	if (ch == 1)
 56 b42d807f 2023-09-02 op 		return ('/');
 57 b42d807f 2023-09-02 op 	errno = EINVAL;
 58 b42d807f 2023-09-02 op 	return (-1);
 59 b42d807f 2023-09-02 op }
 60 b42d807f 2023-09-02 op 
 61 b42d807f 2023-09-02 op static int
 62 b42d807f 2023-09-02 op b64encode(unsigned char *in, size_t ilen, char *out, size_t olen)
 63 b42d807f 2023-09-02 op {
 64 b42d807f 2023-09-02 op 	int		 r;
 65 b42d807f 2023-09-02 op 
 66 b42d807f 2023-09-02 op #define SET(x) {				\
 67 b42d807f 2023-09-02 op 	if ((r = tob64((x) & 0x3F)) == -1)	\
 68 b42d807f 2023-09-02 op 		return (-1);			\
 69 b42d807f 2023-09-02 op 	*out++ = r;				\
 70 b42d807f 2023-09-02 op }
 71 b42d807f 2023-09-02 op 
 72 b42d807f 2023-09-02 op 	while (ilen > 0) {
 73 b42d807f 2023-09-02 op 		if (olen < 4) {
 74 b42d807f 2023-09-02 op 			errno = ENOSPC;
 75 b42d807f 2023-09-02 op 			return (-1);
 76 b42d807f 2023-09-02 op 		}
 77 b42d807f 2023-09-02 op 		olen -= 4;
 78 b42d807f 2023-09-02 op 
 79 b42d807f 2023-09-02 op 		switch (ilen) {
 80 b42d807f 2023-09-02 op 		case 1:
 81 b42d807f 2023-09-02 op 			SET(in[0] >> 2);
 82 b42d807f 2023-09-02 op 			SET(in[0] << 4);
 83 b42d807f 2023-09-02 op 			*out++ = '=';
 84 b42d807f 2023-09-02 op 			*out++ = '=';
 85 b42d807f 2023-09-02 op 			ilen = 0;
 86 b42d807f 2023-09-02 op 			break;
 87 b42d807f 2023-09-02 op 		case 2:
 88 b42d807f 2023-09-02 op 			SET(in[0] >> 2);
 89 b42d807f 2023-09-02 op 			SET(in[0] << 4 | in[1] >> 4);
 90 b42d807f 2023-09-02 op 			SET(in[1] << 2);
 91 b42d807f 2023-09-02 op 			*out++ = '=';
 92 b42d807f 2023-09-02 op 			ilen = 0;
 93 b42d807f 2023-09-02 op 			break;
 94 b42d807f 2023-09-02 op 		default:
 95 b42d807f 2023-09-02 op 			SET(in[0] >> 2);
 96 b42d807f 2023-09-02 op 			SET(in[0] << 4 | in[1] >> 4);
 97 b42d807f 2023-09-02 op 			SET(in[1] << 2 | in[2] >> 6);
 98 b42d807f 2023-09-02 op 			SET(in[2]);
 99 b42d807f 2023-09-02 op 			ilen -= 3;
100 b42d807f 2023-09-02 op 			in += 3;
101 b42d807f 2023-09-02 op 			break;
102 b42d807f 2023-09-02 op 		}
103 b42d807f 2023-09-02 op 	}
104 b42d807f 2023-09-02 op 
105 b42d807f 2023-09-02 op #undef SET
106 b42d807f 2023-09-02 op 
107 b42d807f 2023-09-02 op 	if (olen < 1) {
108 b42d807f 2023-09-02 op 		errno = ENOSPC;
109 b42d807f 2023-09-02 op 		return (-1);
110 b42d807f 2023-09-02 op 	}
111 b42d807f 2023-09-02 op 	*out = '\0';
112 b42d807f 2023-09-02 op 	return (0);
113 b42d807f 2023-09-02 op }
114 b42d807f 2023-09-02 op 
115 b42d807f 2023-09-02 op int
116 b42d807f 2023-09-02 op ws_accept_hdr(const char *secret, char *out, size_t olen)
117 b42d807f 2023-09-02 op {
118 b42d807f 2023-09-02 op 	SHA1_CTX	 ctx;
119 b42d807f 2023-09-02 op 	uint8_t		 hash[SHA1_DIGEST_LENGTH];
120 b42d807f 2023-09-02 op 
121 b42d807f 2023-09-02 op 	SHA1Init(&ctx);
122 b42d807f 2023-09-02 op 	SHA1Update(&ctx, secret, strlen(secret));
123 b42d807f 2023-09-02 op 	SHA1Update(&ctx, WS_GUID, strlen(WS_GUID));
124 b42d807f 2023-09-02 op 	SHA1Final(hash, &ctx);
125 b42d807f 2023-09-02 op 
126 b42d807f 2023-09-02 op 	return (b64encode(hash, sizeof(hash), out, olen));
127 b42d807f 2023-09-02 op }
128 b42d807f 2023-09-02 op 
129 b42d807f 2023-09-02 op int
130 b42d807f 2023-09-02 op ws_read(struct client *clt, int *type, size_t *len)
131 b42d807f 2023-09-02 op {
132 6be81433 2024-04-14 op 	struct buf	*rbuf = &clt->bio.rbuf;
133 b42d807f 2023-09-02 op 	size_t		 i;
134 b42d807f 2023-09-02 op 	uint32_t	 mask;
135 b42d807f 2023-09-02 op 	uint8_t		 first, second, op, plen;
136 b42d807f 2023-09-02 op 
137 b42d807f 2023-09-02 op 	*type = WST_UNKNOWN, *len = 0;
138 b42d807f 2023-09-02 op 
139 b42d807f 2023-09-02 op 	if (rbuf->len < 2) {
140 b42d807f 2023-09-02 op 		errno = EAGAIN;
141 b42d807f 2023-09-02 op 		return (-1);
142 b42d807f 2023-09-02 op 	}
143 b42d807f 2023-09-02 op 
144 b42d807f 2023-09-02 op 	memcpy(&first, &rbuf->buf[0], sizeof(first));
145 b42d807f 2023-09-02 op 	memcpy(&second, &rbuf->buf[1], sizeof(second));
146 b42d807f 2023-09-02 op 
147 b42d807f 2023-09-02 op 	/* for the close message this doesn't seem to be the case... */
148 b42d807f 2023-09-02 op #if 0
149 b42d807f 2023-09-02 op 	/* the reserved bits must be zero, don't care about FIN */
150 b42d807f 2023-09-02 op 	if ((first & 0x0E) != 0) {
151 b42d807f 2023-09-02 op 		errno = EINVAL;
152 b42d807f 2023-09-02 op 		return (-1);
153 b42d807f 2023-09-02 op 	}
154 b42d807f 2023-09-02 op #endif
155 b42d807f 2023-09-02 op 
156 b42d807f 2023-09-02 op 	/* mask must be set for messages sent by the clients */
157 b42d807f 2023-09-02 op 	if ((second >> 7) != 1) {
158 b42d807f 2023-09-02 op 		errno = EINVAL;
159 b42d807f 2023-09-02 op 		return (-1);
160 b42d807f 2023-09-02 op 	}
161 b42d807f 2023-09-02 op 
162 b42d807f 2023-09-02 op 	op = first & 0x0F;
163 b42d807f 2023-09-02 op 	plen = second & 0x7F;
164 b42d807f 2023-09-02 op 
165 b42d807f 2023-09-02 op 	/* don't support extended payload length for now */
166 b42d807f 2023-09-02 op 	if (plen >= 126) {
167 b42d807f 2023-09-02 op 		errno = E2BIG;
168 b42d807f 2023-09-02 op 		return (-1);
169 b42d807f 2023-09-02 op 	}
170 b42d807f 2023-09-02 op 
171 b42d807f 2023-09-02 op 	*len = plen;
172 b42d807f 2023-09-02 op 
173 b42d807f 2023-09-02 op 	switch (op) {
174 b42d807f 2023-09-02 op 	case WST_CONT:
175 b42d807f 2023-09-02 op 	case WST_TEXT:
176 b42d807f 2023-09-02 op 	case WST_BINARY:
177 b42d807f 2023-09-02 op 	case WST_CLOSE:
178 b42d807f 2023-09-02 op 	case WST_PING:
179 b42d807f 2023-09-02 op 		*type = op;
180 b42d807f 2023-09-02 op 		break;
181 b42d807f 2023-09-02 op 	}
182 b42d807f 2023-09-02 op 
183 b42d807f 2023-09-02 op 	if (rbuf->len < sizeof(first) + sizeof(second) + sizeof(mask) + plen) {
184 b42d807f 2023-09-02 op 		errno = EAGAIN;
185 b42d807f 2023-09-02 op 		return (-1);
186 b42d807f 2023-09-02 op 	}
187 b42d807f 2023-09-02 op 
188 b42d807f 2023-09-02 op 	buf_drain(rbuf, 2); /* header */
189 b42d807f 2023-09-02 op 	memcpy(&mask, rbuf->buf, sizeof(mask));
190 b42d807f 2023-09-02 op 	buf_drain(rbuf, 4);
191 b42d807f 2023-09-02 op 
192 b42d807f 2023-09-02 op 	/* decode the payload */
193 b42d807f 2023-09-02 op 	for (i = 0; i < plen; ++i)
194 b42d807f 2023-09-02 op 		rbuf->buf[i] ^= mask >> (8 * (i % 4));
195 b42d807f 2023-09-02 op 
196 b42d807f 2023-09-02 op 	return (0);
197 b42d807f 2023-09-02 op }
198 b42d807f 2023-09-02 op 
199 b42d807f 2023-09-02 op int
200 b42d807f 2023-09-02 op ws_compose(struct client *clt, int type, const void *data, size_t len)
201 b42d807f 2023-09-02 op {
202 b42d807f 2023-09-02 op 	struct bufio	*bio = &clt->bio;
203 b42d807f 2023-09-02 op 	uint16_t	 extlen = 0;
204 b42d807f 2023-09-02 op 	uint8_t		 first, second;
205 b42d807f 2023-09-02 op 
206 b42d807f 2023-09-02 op 	first = (type & 0x0F) | 0x80;
207 b42d807f 2023-09-02 op 
208 b42d807f 2023-09-02 op 	if (len < 126)
209 b42d807f 2023-09-02 op 		second = len;
210 b42d807f 2023-09-02 op 	else {
211 b42d807f 2023-09-02 op 		second = 126;
212 b42d807f 2023-09-02 op 
213 b42d807f 2023-09-02 op 		/*
214 b42d807f 2023-09-02 op 		 * for the extended length, the most significant bit
215 b42d807f 2023-09-02 op 		 * must be zero.  We could use the 64 bit field but
216 b42d807f 2023-09-02 op 		 * it's a waste.
217 b42d807f 2023-09-02 op 		 */
218 b42d807f 2023-09-02 op 		if (len > 0x7FFF) {
219 b42d807f 2023-09-02 op 			errno = ERANGE;
220 b42d807f 2023-09-02 op 			return (-1);
221 b42d807f 2023-09-02 op 		}
222 b42d807f 2023-09-02 op 		extlen = htons(len);
223 b42d807f 2023-09-02 op 	}
224 b42d807f 2023-09-02 op 
225 b42d807f 2023-09-02 op 	if (bufio_compose(bio, &first, 1) == -1 ||
226 b42d807f 2023-09-02 op 	    bufio_compose(bio, &second, 1) == -1)
227 b42d807f 2023-09-02 op 		goto err;
228 b42d807f 2023-09-02 op 
229 b42d807f 2023-09-02 op 	if (extlen != 0 && bufio_compose(bio, &extlen, sizeof(extlen)) == -1)
230 b42d807f 2023-09-02 op 		goto err;
231 b42d807f 2023-09-02 op 
232 b42d807f 2023-09-02 op 	if (bufio_compose(bio, data, len) == -1)
233 b42d807f 2023-09-02 op 		goto err;
234 b42d807f 2023-09-02 op 
235 b42d807f 2023-09-02 op 	return (0);
236 b42d807f 2023-09-02 op 
237 b42d807f 2023-09-02 op  err:
238 b42d807f 2023-09-02 op 	clt->err = 1;
239 b42d807f 2023-09-02 op 	return (-1);
240 b42d807f 2023-09-02 op }