lib/private-libwebsockets.h

   1 /*
   2  * libwebsockets - small server side websockets and web server implementation
   3  *
   4  * Copyright (C) 2010 Andy Green <andy@warmcat.com>
   5  *
   6  *  This library is free software; you can redistribute it and/or
   7  *  modify it under the terms of the GNU Lesser General Public
   8  *  License as published by the Free Software Foundation:
   9  *  version 2.1 of the License.
  10  *
  11  *  This library is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  *  Lesser General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU Lesser General Public
  17  *  License along with this library; if not, write to the Free Software
  18  *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
  19  *  MA  02110-1301  USA
  20  */
  21
  22 #include <unistd.h>
  23 #include <stdio.h>
  24 #include <stdlib.h>
  25 #include <string.h>
  26 #include <strings.h>
  27 #include <ctype.h>
  28 #include <errno.h>
  29 #include <fcntl.h>
  30 #include <signal.h>
  31 #include <netdb.h>
  32 #include <stdarg.h>
  33
  34 #include <sys/stat.h>
  35
  36 #ifdef WIN32
  37
  38 #include <time.h >
  39 #include <winsock2.h>
  40 #include <ws2ipdef.h>
  41 #include <windows.h>
  42
  43 #else
  44
  45 #include <sys/types.h>
  46 #include <sys/socket.h>
  47 #ifndef LWS_NO_FORK
  48 #include <sys/prctl.h>
  49 #endif
  50 #include <netinet/in.h>
  51 #include <netinet/tcp.h>
  52 #include <arpa/inet.h>
  53
  54 #include <poll.h>
  55 #include <sys/mman.h>
  56 #include <sys/time.h>
  57
  58 #endif
  59
  60 #ifdef LWS_OPENSSL_SUPPORT
  61 #include <openssl/ssl.h>
  62 #include <openssl/evp.h>
  63 #include <openssl/err.h>
  64 #include <openssl/md5.h>
  65 #include <openssl/sha.h>
  66 #endif
  67
  68
  69 #include "libwebsockets.h"
  70
  71 #if 0
  72 #define DEBUG
  73 #endif
  74
  75 #ifdef DEBUG
  76 #ifdef WIN32
  77 static
  78 #else
  79 static inline
  80 #endif
  81 void debug(const char *format, ...)
  82 {
  83         va_list ap;
  84         va_start(ap, format); vfprintf(stderr, format, ap); va_end(ap);
  85 }
  86 #else
  87 #ifdef WIN32
  88 static
  89 #else
  90 static inline
  91 #endif
  92 void debug(const char *format, ...)
  93 {
  94 }
  95 #endif
  96
  97
  98 /*
  99  * Mac OSX as well as iOS do not define the MSG_NOSIGNAL flag,
 100  * but happily have something equivalent in the SO_NOSIGPIPE flag.
 101  */
 102 #ifdef __APPLE__
 103 #define MSG_NOSIGNAL SO_NOSIGPIPE
 104 #endif
 105
 106
 107 #define FD_HASHTABLE_MODULUS 32
 108 #define MAX_CLIENTS 100
 109 #define LWS_MAX_HEADER_NAME_LENGTH 64
 110 #define LWS_MAX_HEADER_LEN 4096
 111 #define LWS_INITIAL_HDR_ALLOC 256
 112 #define LWS_ADDITIONAL_HDR_ALLOC 64
 113 #define MAX_USER_RX_BUFFER 4096
 114 #define MAX_BROADCAST_PAYLOAD 2048
 115 #define LWS_MAX_PROTOCOLS 10
 116 #define LWS_MAX_EXTENSIONS_ACTIVE 10
 117 #define SPEC_LATEST_SUPPORTED 7
 118
 119 #define MAX_WEBSOCKET_04_KEY_LEN 128
 120 #define SYSTEM_RANDOM_FILEPATH "/dev/urandom"
 121
 122 enum lws_websocket_opcodes_04 {
 123         LWS_WS_OPCODE_04__CONTINUATION = 0,
 124         LWS_WS_OPCODE_04__CLOSE = 1,
 125         LWS_WS_OPCODE_04__PING = 2,
 126         LWS_WS_OPCODE_04__PONG = 3,
 127         LWS_WS_OPCODE_04__TEXT_FRAME = 4,
 128         LWS_WS_OPCODE_04__BINARY_FRAME = 5,
 129
 130         LWS_WS_OPCODE_04__RESERVED_6 = 6,
 131         LWS_WS_OPCODE_04__RESERVED_7 = 7,
 132         LWS_WS_OPCODE_04__RESERVED_8 = 8,
 133         LWS_WS_OPCODE_04__RESERVED_9 = 9,
 134         LWS_WS_OPCODE_04__RESERVED_A = 0xa,
 135         LWS_WS_OPCODE_04__RESERVED_B = 0xb,
 136         LWS_WS_OPCODE_04__RESERVED_C = 0xc,
 137         LWS_WS_OPCODE_04__RESERVED_D = 0xd,
 138         LWS_WS_OPCODE_04__RESERVED_E = 0xe,
 139         LWS_WS_OPCODE_04__RESERVED_F = 0xf,
 140 };
 141
 142 enum lws_websocket_opcodes_07 {
 143         LWS_WS_OPCODE_07__CONTINUATION = 0,
 144         LWS_WS_OPCODE_07__TEXT_FRAME = 1,
 145         LWS_WS_OPCODE_07__BINARY_FRAME = 2,
 146
 147         LWS_WS_OPCODE_07__NOSPEC__MUX = 7,
 148
 149         /* control extensions 8+ */
 150
 151         LWS_WS_OPCODE_07__CLOSE = 8,
 152         LWS_WS_OPCODE_07__PING = 9,
 153         LWS_WS_OPCODE_07__PONG = 0xa,
 154 };
 155
 156
 157 enum lws_connection_states {
 158         WSI_STATE_HTTP,
 159         WSI_STATE_HTTP_HEADERS,
 160         WSI_STATE_DEAD_SOCKET,
 161         WSI_STATE_ESTABLISHED,
 162         WSI_STATE_CLIENT_UNCONNECTED,
 163         WSI_STATE_RETURNED_CLOSE_ALREADY,
 164         WSI_STATE_AWAITING_CLOSE_ACK,
 165 };
 166
 167 enum lws_rx_parse_state {
 168         LWS_RXPS_NEW,
 169
 170         LWS_RXPS_SEEN_76_FF,
 171         LWS_RXPS_PULLING_76_LENGTH,
 172         LWS_RXPS_EAT_UNTIL_76_FF,
 173
 174         LWS_RXPS_04_MASK_NONCE_1,
 175         LWS_RXPS_04_MASK_NONCE_2,
 176         LWS_RXPS_04_MASK_NONCE_3,
 177
 178         LWS_RXPS_04_FRAME_HDR_1,
 179         LWS_RXPS_04_FRAME_HDR_LEN,
 180         LWS_RXPS_04_FRAME_HDR_LEN16_2,
 181         LWS_RXPS_04_FRAME_HDR_LEN16_1,
 182         LWS_RXPS_04_FRAME_HDR_LEN64_8,
 183         LWS_RXPS_04_FRAME_HDR_LEN64_7,
 184         LWS_RXPS_04_FRAME_HDR_LEN64_6,
 185         LWS_RXPS_04_FRAME_HDR_LEN64_5,
 186         LWS_RXPS_04_FRAME_HDR_LEN64_4,
 187         LWS_RXPS_04_FRAME_HDR_LEN64_3,
 188         LWS_RXPS_04_FRAME_HDR_LEN64_2,
 189         LWS_RXPS_04_FRAME_HDR_LEN64_1,
 190
 191         LWS_RXPS_07_COLLECT_FRAME_KEY_1,
 192         LWS_RXPS_07_COLLECT_FRAME_KEY_2,
 193         LWS_RXPS_07_COLLECT_FRAME_KEY_3,
 194         LWS_RXPS_07_COLLECT_FRAME_KEY_4,
 195
 196         LWS_RXPS_PAYLOAD_UNTIL_LENGTH_EXHAUSTED
 197 };
 198
 199
 200 enum connection_mode {
 201         LWS_CONNMODE_WS_SERVING,
 202         LWS_CONNMODE_WS_CLIENT,
 203
 204         /* transient modes */
 205         LWS_CONNMODE_WS_CLIENT_WAITING_PROXY_REPLY,
 206         LWS_CONNMODE_WS_CLIENT_ISSUE_HANDSHAKE,
 207         LWS_CONNMODE_WS_CLIENT_WAITING_SERVER_REPLY,
 208         LWS_CONNMODE_WS_CLIENT_WAITING_EXTENSION_CONNECT,
 209         LWS_CONNMODE_WS_CLIENT_PENDING_CANDIDATE_CHILD,
 210
 211         /* special internal types */
 212         LWS_CONNMODE_SERVER_LISTENER,
 213         LWS_CONNMODE_BROADCAST_PROXY_LISTENER,
 214         LWS_CONNMODE_BROADCAST_PROXY
 215 };
 216
 217
 218 #define LWS_FD_HASH(fd) ((fd ^ (fd >> 8) ^ (fd >> 16)) % FD_HASHTABLE_MODULUS)
 219
 220 struct libwebsocket_fd_hashtable {
 221         struct libwebsocket *wsi[MAX_CLIENTS + 1];
 222         int length;
 223 };
 224
 225 struct libwebsocket_protocols;
 226
 227 struct libwebsocket_context {
 228         struct libwebsocket_fd_hashtable fd_hashtable[FD_HASHTABLE_MODULUS];
 229         struct pollfd fds[MAX_CLIENTS * FD_HASHTABLE_MODULUS + 1];
 230         int fds_count;
 231         int listen_port;
 232         char http_proxy_address[256];
 233         char canonical_hostname[1024];
 234         unsigned int http_proxy_port;
 235         unsigned int options;
 236         unsigned long last_timeout_check_s;
 237
 238         int fd_random;
 239
 240 #ifdef LWS_OPENSSL_SUPPORT
 241         int use_ssl;
 242         SSL_CTX *ssl_ctx;
 243         SSL_CTX *ssl_client_ctx;
 244 #endif
 245         struct libwebsocket_protocols *protocols;
 246         int count_protocols;
 247         struct libwebsocket_extension *extensions;
 248 };
 249
 250
 251 enum pending_timeout {
 252         NO_PENDING_TIMEOUT = 0,
 253         PENDING_TIMEOUT_AWAITING_PROXY_RESPONSE,
 254         PENDING_TIMEOUT_ESTABLISH_WITH_SERVER,
 255         PENDING_TIMEOUT_AWAITING_SERVER_RESPONSE,
 256         PENDING_TIMEOUT_AWAITING_PING,
 257         PENDING_TIMEOUT_CLOSE_ACK,
 258         PENDING_TIMEOUT_AWAITING_EXTENSION_CONNECT_RESPONSE,
 259 };
 260
 261
 262 /*
 263  * This is totally opaque to code using the library.  It's exported as a
 264  * forward-reference pointer-only declaration; the user can use the pointer with
 265  * other APIs to get information out of it.
 266  */
 267
 268 struct libwebsocket {
 269         const struct libwebsocket_protocols *protocol;
 270         struct libwebsocket_extension *
 271                                    active_extensions[LWS_MAX_EXTENSIONS_ACTIVE];
 272         void * active_extensions_user[LWS_MAX_EXTENSIONS_ACTIVE];
 273         int count_active_extensions;
 274
 275         enum lws_connection_states state;
 276
 277         char name_buffer[LWS_MAX_HEADER_NAME_LENGTH];
 278         int name_buffer_pos;
 279         int current_alloc_len;
 280         enum lws_token_indexes parser_state;
 281         struct lws_tokens utf8_token[WSI_TOKEN_COUNT];
 282         int ietf_spec_revision;
 283         char rx_user_buffer[LWS_SEND_BUFFER_PRE_PADDING + MAX_USER_RX_BUFFER +
 284                                                   LWS_SEND_BUFFER_POST_PADDING];
 285         int rx_user_buffer_head;
 286         enum libwebsocket_write_protocol rx_frame_type;
 287         int protocol_index_for_broadcast_proxy;
 288         enum pending_timeout pending_timeout;
 289         unsigned long pending_timeout_limit;
 290
 291         int sock;
 292
 293         enum lws_rx_parse_state lws_rx_parse_state;
 294         char extension_data_pending;
 295         struct libwebsocket *candidate_children_list;
 296         struct libwebsocket *extension_handles;
 297
 298         /* 04 protocol specific */
 299
 300         char key_b64[150];
 301         unsigned char masking_key_04[20];
 302         unsigned char frame_masking_nonce_04[4];
 303         unsigned char frame_mask_04[20];
 304         unsigned char frame_mask_index;
 305         size_t rx_packet_length;
 306         unsigned char opcode;
 307         unsigned char final;
 308
 309         int pings_vs_pongs;
 310         unsigned char (*xor_mask)(struct libwebsocket *, unsigned char);
 311         char all_zero_nonce;
 312
 313         enum lws_close_status close_reason;
 314
 315         /* 07 specific */
 316         char this_frame_masked;
 317
 318         /* client support */
 319         char initial_handshake_hash_base64[30];
 320         enum connection_mode mode;
 321         char *c_path;
 322         char *c_host;
 323         char *c_origin;
 324         char *c_protocol;
 325
 326         char *c_address;
 327         int c_port;
 328
 329
 330 #ifdef LWS_OPENSSL_SUPPORT
 331         SSL *ssl;
 332         BIO *client_bio;
 333         int use_ssl;
 334 #endif
 335
 336         void *user_space;
 337 };
 338
 339 extern int
 340 libwebsocket_client_rx_sm(struct libwebsocket *wsi, unsigned char c);
 341
 342 extern int
 343 libwebsocket_parse(struct libwebsocket *wsi, unsigned char c);
 344
 345 extern int
 346 libwebsocket_interpret_incoming_packet(struct libwebsocket *wsi,
 347                                                 unsigned char *buf, size_t len);
 348
 349 extern int
 350 libwebsocket_read(struct libwebsocket_context *context, struct libwebsocket *wsi,
 351                                                unsigned char * buf, size_t len);
 352
 353 extern int
 354 lws_b64_selftest(void);
 355
 356 extern unsigned char
 357 xor_no_mask(struct libwebsocket *wsi, unsigned char c);
 358
 359 extern unsigned char
 360 xor_mask_04(struct libwebsocket *wsi, unsigned char c);
 361
 362 extern unsigned char
 363 xor_mask_05(struct libwebsocket *wsi, unsigned char c);
 364
 365 extern struct libwebsocket *
 366 wsi_from_fd(struct libwebsocket_context *context, int fd);
 367
 368 extern int
 369 insert_wsi(struct libwebsocket_context *context, struct libwebsocket *wsi);
 370
 371 extern int
 372 delete_from_fd(struct libwebsocket_context *context, int fd);
 373
 374 extern void
 375 libwebsocket_set_timeout(struct libwebsocket *wsi,
 376                                          enum pending_timeout reason, int secs);
 377
 378 extern int
 379 lws_issue_raw(struct libwebsocket *wsi, unsigned char *buf, size_t len);
 380
 381
 382 extern void
 383 libwebsocket_service_timeout_check(struct libwebsocket_context *context,
 384                                     struct libwebsocket *wsi, unsigned int sec);
 385
 386 extern struct libwebsocket * __libwebsocket_client_connect_2(
 387         struct libwebsocket_context *context,
 388         struct libwebsocket *wsi);
 389
 390 extern struct libwebsocket *
 391 libwebsocket_create_new_server_wsi(struct libwebsocket_context *context);
 392
 393 extern char *
 394 libwebsockets_generate_client_handshake(struct libwebsocket_context *context,
 395                 struct libwebsocket *wsi, char *pkt);
 396
 397 extern int
 398 lws_handle_POLLOUT_event(struct libwebsocket_context *context,
 399                               struct libwebsocket *wsi, struct pollfd *pollfd);
 400
 401 extern int
 402 lws_any_extension_handled(struct libwebsocket_context *context,
 403                                                        struct libwebsocket *wsi,
 404                                                        enum libwebsocket_extension_callback_reasons r,
 405                                                        void *v, size_t len);
 406
 407 extern void *
 408 lws_get_extension_user_matching_ext(struct libwebsocket *wsi,
 409                                                         struct libwebsocket_extension * ext);
 410
 411 extern int
 412 lws_client_interpret_server_handshake(struct libwebsocket_context *context,
 413                 struct libwebsocket *wsi);
 414
 415 extern int
 416 libwebsocket_rx_sm(struct libwebsocket *wsi, unsigned char c);
 417
 418 extern int
 419 lws_issue_raw_ext_access(struct libwebsocket *wsi,
 420                                                 unsigned char *buf, size_t len);
 421
 422 #ifndef LWS_OPENSSL_SUPPORT
 423
 424 unsigned char *
 425 SHA1(const unsigned char *d, size_t n, unsigned char *md);
 426
 427 void
 428 MD5(const unsigned char *input, int ilen, unsigned char *output);
 429
 430 #endif