Andy Green | 4739e5c | 2011-01-22 12:51:57 +0000 | [diff] [blame^] | 1 | #include "private-libwebsockets.h" |
| 2 | #include <netdb.h> |
| 3 | |
| 4 | |
| 5 | /* |
| 6 | * In-place str to lower case |
| 7 | */ |
| 8 | |
| 9 | void |
| 10 | strtolower(char *s) |
| 11 | { |
| 12 | while (*s) |
| 13 | *s++ = tolower(*s); |
| 14 | } |
| 15 | |
| 16 | void |
| 17 | libwebsocket_client_close(struct libwebsocket *wsi) |
| 18 | { |
| 19 | int n = wsi->state; |
| 20 | struct libwebsocket_context *clients; |
| 21 | |
| 22 | /* mark the WSI as dead and let the callback know */ |
| 23 | |
| 24 | wsi->state = WSI_STATE_DEAD_SOCKET; |
| 25 | |
| 26 | if (wsi->protocol) { |
| 27 | if (wsi->protocol->callback && n == WSI_STATE_ESTABLISHED) |
| 28 | wsi->protocol->callback(wsi, LWS_CALLBACK_CLOSED, |
| 29 | wsi->user_space, NULL, 0); |
| 30 | |
| 31 | /* remove it from the client polling list */ |
| 32 | clients = wsi->protocol->owning_server; |
| 33 | if (clients) |
| 34 | for (n = 0; n < clients->fds_count; n++) { |
| 35 | if (clients->wsi[n] != wsi) |
| 36 | continue; |
| 37 | while (n < clients->fds_count - 1) { |
| 38 | clients->fds[n] = clients->fds[n + 1]; |
| 39 | clients->wsi[n] = clients->wsi[n + 1]; |
| 40 | } |
| 41 | /* we only have to deal with one */ |
| 42 | n = clients->fds_count; |
| 43 | } |
| 44 | |
| 45 | } |
| 46 | |
| 47 | /* clean out any parsing allocations */ |
| 48 | |
| 49 | for (n = 0; n < WSI_TOKEN_COUNT; n++) |
| 50 | if (wsi->utf8_token[n].token) |
| 51 | free(wsi->utf8_token[n].token); |
| 52 | |
| 53 | /* shut down reasonably cleanly */ |
| 54 | |
| 55 | #ifdef LWS_OPENSSL_SUPPORT |
| 56 | if (use_ssl) { |
| 57 | n = SSL_get_fd(wsi->ssl); |
| 58 | SSL_shutdown(wsi->ssl); |
| 59 | close(n); |
| 60 | SSL_free(wsi->ssl); |
| 61 | } else { |
| 62 | #endif |
| 63 | shutdown(wsi->sock, SHUT_RDWR); |
| 64 | close(wsi->sock); |
| 65 | #ifdef LWS_OPENSSL_SUPPORT |
| 66 | } |
| 67 | #endif |
| 68 | } |
| 69 | |
| 70 | struct libwebsocket * |
| 71 | libwebsocket_client_connect(struct libwebsocket_context *clients, |
| 72 | const char *address, |
| 73 | int port, |
| 74 | const char *path, |
| 75 | const char *host, |
| 76 | const char *origin, |
| 77 | const char *protocol) |
| 78 | { |
| 79 | struct hostent *server_hostent; |
| 80 | struct sockaddr_in server_addr; |
| 81 | char buf[150]; |
| 82 | char key_b64[150]; |
| 83 | char hash[20]; |
| 84 | int fd; |
| 85 | struct pollfd pfd; |
| 86 | static const char magic_websocket_guid[] = |
| 87 | "258EAFA5-E914-47DA-95CA-C5AB0DC85B11"; |
| 88 | static const char magic_websocket_04_masking_guid[] = |
| 89 | "61AC5F19-FBBA-4540-B96F-6561F1AB40A8"; |
| 90 | char pkt[1024]; |
| 91 | char *p = &pkt[0]; |
| 92 | const char * pc; |
| 93 | int len; |
| 94 | int okay = 0; |
| 95 | struct libwebsocket *wsi; |
| 96 | int n; |
| 97 | |
| 98 | wsi = malloc(sizeof (struct libwebsocket)); |
| 99 | if (wsi == NULL) |
| 100 | return NULL; |
| 101 | |
| 102 | clients->wsi[clients->fds_count] = wsi; |
| 103 | |
| 104 | wsi->ietf_spec_revision = 4; |
| 105 | wsi->name_buffer_pos = 0; |
| 106 | wsi->user_space = NULL; |
| 107 | wsi->state = WSI_STATE_CLIENT_UNCONNECTED; |
| 108 | wsi->pings_vs_pongs = 0; |
| 109 | |
| 110 | for (n = 0; n < WSI_TOKEN_COUNT; n++) { |
| 111 | wsi->utf8_token[n].token = NULL; |
| 112 | wsi->utf8_token[n].token_len = 0; |
| 113 | } |
| 114 | |
| 115 | /* |
| 116 | * prepare the actual connection |
| 117 | */ |
| 118 | |
| 119 | server_hostent = gethostbyname(address); |
| 120 | if (server_hostent == NULL) { |
| 121 | fprintf(stderr, "Unable to get host name from %s\n", address); |
| 122 | goto bail1; |
| 123 | } |
| 124 | |
| 125 | wsi->sock = socket(AF_INET, SOCK_STREAM, 0); |
| 126 | |
| 127 | if (wsi->sock < 0) { |
| 128 | fprintf(stderr, "Unable to open socket\n"); |
| 129 | goto bail1; |
| 130 | } |
| 131 | |
| 132 | |
| 133 | server_addr.sin_family = AF_INET; |
| 134 | server_addr.sin_port = htons(port); |
| 135 | server_addr.sin_addr = *((struct in_addr *)server_hostent->h_addr); |
| 136 | bzero(&server_addr.sin_zero, 8); |
| 137 | |
| 138 | if (connect(wsi->sock, (struct sockaddr *)&server_addr, |
| 139 | sizeof(struct sockaddr)) == -1) { |
| 140 | fprintf(stderr, "Connect failed"); |
| 141 | goto bail1; |
| 142 | } |
| 143 | |
| 144 | /* |
| 145 | * create the random key |
| 146 | */ |
| 147 | |
| 148 | fd = open(SYSTEM_RANDOM_FILEPATH, O_RDONLY); |
| 149 | if (fd < 1) { |
| 150 | fprintf(stderr, "Unable to open random device %s\n", |
| 151 | SYSTEM_RANDOM_FILEPATH); |
| 152 | goto bail2; |
| 153 | } |
| 154 | n = read(fd, hash, 16); |
| 155 | if (n != 16) { |
| 156 | fprintf(stderr, "Unable to read from random device %s\n", |
| 157 | SYSTEM_RANDOM_FILEPATH); |
| 158 | close(fd); |
| 159 | goto bail2; |
| 160 | } |
| 161 | close(fd); |
| 162 | |
| 163 | lws_b64_encode_string(hash, 16, key_b64, sizeof key_b64); |
| 164 | |
| 165 | /* |
| 166 | * 04 example client handshake |
| 167 | * |
| 168 | * GET /chat HTTP/1.1 |
| 169 | * Host: server.example.com |
| 170 | * Upgrade: websocket |
| 171 | * Connection: Upgrade |
| 172 | * Sec-WebSocket-Key: dGhlIHNhbXBsZSBub25jZQ== |
| 173 | * Sec-WebSocket-Origin: http://example.com |
| 174 | * Sec-WebSocket-Protocol: chat, superchat |
| 175 | * Sec-WebSocket-Version: 4 |
| 176 | */ |
| 177 | |
| 178 | p += sprintf(p, "GET %s HTTP/1.1\x0d\x0a", path); |
| 179 | p += sprintf(p, "Host: %s\x0d\x0a", host); |
| 180 | p += sprintf(p, "Upgrade: websocket\x0d\x0a"); |
| 181 | p += sprintf(p, "Connection: Upgrade\x0d\x0aSec-WebSocket-Key: "); |
| 182 | strcpy(p, key_b64); |
| 183 | p += strlen(key_b64); |
| 184 | p += sprintf(p, "\x0d\x0aSec-WebSocket-Origin: %s\x0d\x0a", origin); |
| 185 | if (protocol != NULL) |
| 186 | p += sprintf(p, "Sec-WebSocket-Protocol: %s\x0d\x0a", protocol); |
| 187 | p += sprintf(p, "Sec-WebSocket-Version: 4\x0d\x0a\x0d\x0a"); |
| 188 | |
| 189 | |
| 190 | /* prepare the expected server accept response */ |
| 191 | |
| 192 | strcpy(buf, key_b64); |
| 193 | strcpy(&buf[strlen(buf)], magic_websocket_guid); |
| 194 | |
| 195 | SHA1((unsigned char *)buf, strlen(buf), (unsigned char *)hash); |
| 196 | |
| 197 | lws_b64_encode_string(hash, 20, wsi->initial_handshake_hash_base64, |
| 198 | sizeof wsi->initial_handshake_hash_base64); |
| 199 | |
| 200 | /* send our request to the server */ |
| 201 | |
| 202 | n = send(wsi->sock, pkt, p - pkt, 0); |
| 203 | |
| 204 | wsi->parser_state = WSI_TOKEN_NAME_PART; |
| 205 | |
| 206 | pfd.fd = wsi->sock; |
| 207 | pfd.events = POLLIN; |
| 208 | pfd.revents = 0; |
| 209 | |
| 210 | n = poll(&pfd, 1, 5000); |
| 211 | if (n < 0) { |
| 212 | fprintf(stderr, "libwebsocket_client_handshake socket error " |
| 213 | "while waiting for handshake response"); |
| 214 | goto bail2; |
| 215 | } |
| 216 | if (n == 0) { |
| 217 | fprintf(stderr, "libwebsocket_client_handshake timeout " |
| 218 | "while waiting for handshake response"); |
| 219 | goto bail2; |
| 220 | } |
| 221 | |
| 222 | /* interpret the server response */ |
| 223 | |
| 224 | /* |
| 225 | * HTTP/1.1 101 Switching Protocols |
| 226 | * Upgrade: websocket |
| 227 | * Connection: Upgrade |
| 228 | * Sec-WebSocket-Accept: me89jWimTRKTWwrS3aRrL53YZSo= |
| 229 | * Sec-WebSocket-Nonce: AQIDBAUGBwgJCgsMDQ4PEC== |
| 230 | * Sec-WebSocket-Protocol: chat |
| 231 | */ |
| 232 | |
| 233 | len = recv(wsi->sock, pkt, sizeof pkt, 0); |
| 234 | if (len < 0) { |
| 235 | fprintf(stderr, "libwebsocket_client_handshake read error\n"); |
| 236 | goto bail2; |
| 237 | } |
| 238 | |
| 239 | p = pkt; |
| 240 | for (n = 0; n < len; n++) |
| 241 | libwebsocket_parse(wsi, *p++); |
| 242 | |
| 243 | if (wsi->parser_state != WSI_PARSING_COMPLETE) { |
| 244 | fprintf(stderr, "libwebsocket_client_handshake server response" |
| 245 | " failed parsing\n"); |
| 246 | goto bail2; |
| 247 | } |
| 248 | |
| 249 | /* |
| 250 | * well, what the server sent looked reasonable for syntax. |
| 251 | * Now let's confirm it sent all the necessary headers |
| 252 | */ |
| 253 | |
| 254 | if (!wsi->utf8_token[WSI_TOKEN_HTTP].token_len || |
| 255 | !wsi->utf8_token[WSI_TOKEN_UPGRADE].token_len || |
| 256 | !wsi->utf8_token[WSI_TOKEN_CONNECTION].token_len || |
| 257 | !wsi->utf8_token[WSI_TOKEN_ACCEPT].token_len || |
| 258 | !wsi->utf8_token[WSI_TOKEN_NONCE].token_len || |
| 259 | (!wsi->utf8_token[WSI_TOKEN_PROTOCOL].token_len && |
| 260 | protocol != NULL)) { |
| 261 | fprintf(stderr, "libwebsocket_client_handshake " |
| 262 | "missing required header\n"); |
| 263 | goto bail2; |
| 264 | } |
| 265 | |
| 266 | /* |
| 267 | * Everything seems to be there, now take a closer look at what is in |
| 268 | * each header |
| 269 | */ |
| 270 | |
| 271 | strtolower(wsi->utf8_token[WSI_TOKEN_HTTP].token); |
| 272 | if (strcmp(wsi->utf8_token[WSI_TOKEN_HTTP].token, |
| 273 | "101 switching protocols")) { |
| 274 | fprintf(stderr, "libwebsocket_client_handshake server sent bad" |
| 275 | " HTTP response '%s'\n", |
| 276 | wsi->utf8_token[WSI_TOKEN_HTTP].token); |
| 277 | goto bail2; |
| 278 | } |
| 279 | |
| 280 | strtolower(wsi->utf8_token[WSI_TOKEN_UPGRADE].token); |
| 281 | if (strcmp(wsi->utf8_token[WSI_TOKEN_UPGRADE].token, "websocket")) { |
| 282 | fprintf(stderr, "libwebsocket_client_handshake server sent bad" |
| 283 | " Upgrade header '%s'\n", |
| 284 | wsi->utf8_token[WSI_TOKEN_UPGRADE].token); |
| 285 | goto bail2; |
| 286 | } |
| 287 | |
| 288 | strtolower(wsi->utf8_token[WSI_TOKEN_CONNECTION].token); |
| 289 | if (strcmp(wsi->utf8_token[WSI_TOKEN_CONNECTION].token, "upgrade")) { |
| 290 | fprintf(stderr, "libwebsocket_client_handshake server sent bad" |
| 291 | " Connection hdr '%s'\n", |
| 292 | wsi->utf8_token[WSI_TOKEN_CONNECTION].token); |
| 293 | goto bail2; |
| 294 | } |
| 295 | /* |
| 296 | * confirm the protocol the server wants to talk was in the list of |
| 297 | * protocols we offered |
| 298 | */ |
| 299 | |
| 300 | if (!wsi->utf8_token[WSI_TOKEN_PROTOCOL].token_len) { |
| 301 | |
| 302 | /* no protocol name to work from, default to first protocol */ |
| 303 | wsi->protocol = &clients->protocols[0]; |
| 304 | |
| 305 | goto check_accept; |
| 306 | } |
| 307 | |
| 308 | pc = protocol; |
| 309 | while (*pc && !okay) { |
| 310 | if ((!strncmp(pc, wsi->utf8_token[WSI_TOKEN_PROTOCOL].token, |
| 311 | wsi->utf8_token[WSI_TOKEN_PROTOCOL].token_len)) && |
| 312 | (pc[wsi->utf8_token[WSI_TOKEN_PROTOCOL].token_len] == ',' || |
| 313 | pc[wsi->utf8_token[WSI_TOKEN_PROTOCOL].token_len] == '\0')) { |
| 314 | okay = 1; |
| 315 | continue; |
| 316 | } |
| 317 | while (*pc && *pc != ',') |
| 318 | pc++; |
| 319 | while (*pc && *pc != ' ') |
| 320 | pc++; |
| 321 | } |
| 322 | if (!okay) { |
| 323 | fprintf(stderr, "libwebsocket_client_handshake server " |
| 324 | "sent bad protocol '%s'\n", |
| 325 | wsi->utf8_token[WSI_TOKEN_PROTOCOL].token); |
| 326 | goto bail2; |
| 327 | } |
| 328 | |
| 329 | /* |
| 330 | * identify the selected protocol struct and set it |
| 331 | */ |
| 332 | n = 0; |
| 333 | wsi->protocol = NULL; |
| 334 | while (clients->protocols[n].callback) { |
| 335 | if (strcmp(wsi->utf8_token[WSI_TOKEN_PROTOCOL].token, |
| 336 | clients->protocols[n].name) == 0) |
| 337 | wsi->protocol = &clients->protocols[n]; |
| 338 | n++; |
| 339 | } |
| 340 | |
| 341 | if (wsi->protocol == NULL) { |
| 342 | fprintf(stderr, "libwebsocket_client_handshake server " |
| 343 | "requested protocol '%s', which we " |
| 344 | "said we supported but we don't!\n", |
| 345 | wsi->utf8_token[WSI_TOKEN_PROTOCOL].token); |
| 346 | goto bail2; |
| 347 | } |
| 348 | |
| 349 | check_accept: |
| 350 | /* |
| 351 | * Confirm his accept token is the same as the one we precomputed |
| 352 | */ |
| 353 | |
| 354 | if (strcmp(wsi->utf8_token[WSI_TOKEN_ACCEPT].token, |
| 355 | wsi->initial_handshake_hash_base64)) { |
| 356 | fprintf(stderr, "libwebsocket_client_handshake server sent " |
| 357 | "bad ACCEPT '%s' vs computed '%s'\n", |
| 358 | wsi->utf8_token[WSI_TOKEN_ACCEPT].token, |
| 359 | wsi->initial_handshake_hash_base64); |
| 360 | goto bail2; |
| 361 | } |
| 362 | |
| 363 | /* |
| 364 | * Calculate the masking key to use when sending data to server |
| 365 | */ |
| 366 | |
| 367 | strcpy(buf, key_b64); |
| 368 | p = buf + strlen(key_b64); |
| 369 | strcpy(p, wsi->utf8_token[WSI_TOKEN_NONCE].token); |
| 370 | p += wsi->utf8_token[WSI_TOKEN_NONCE].token_len; |
| 371 | strcpy(p, magic_websocket_04_masking_guid); |
| 372 | SHA1((unsigned char *)buf, strlen(buf), wsi->masking_key_04); |
| 373 | |
| 374 | /* okay he is good to go */ |
| 375 | |
| 376 | clients->fds[clients->fds_count].fd = wsi->sock; |
| 377 | clients->fds[clients->fds_count].revents = 0; |
| 378 | clients->fds[clients->fds_count++].events = POLLIN; |
| 379 | |
| 380 | wsi->state = WSI_STATE_ESTABLISHED; |
| 381 | wsi->client_mode = 1; |
| 382 | |
| 383 | fprintf(stderr, "handshake OK for protocol %s\n", wsi->protocol->name); |
| 384 | |
| 385 | return wsi; |
| 386 | |
| 387 | |
| 388 | bail2: |
| 389 | libwebsocket_client_close(wsi); |
| 390 | bail1: |
| 391 | free(wsi); |
| 392 | |
| 393 | return NULL; |
| 394 | } |