src/lib/raop.c

   1 /**
   2  *  Copyright (C) 2011-2012  Juho Vähä-Herttua
   3  *
   4  *  This library is free software; you can redistribute it and/or
   5  *  modify it under the terms of the GNU Lesser General Public
   6  *  License as published by the Free Software Foundation; either
   7  *  version 2.1 of the License, or (at your option) any later version.
   8  *
   9  *  This library is distributed in the hope that it will be useful,
  10  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  *  Lesser General Public License for more details.
  13  */
  14
  15 #include <stdlib.h>
  16 #include <stdio.h>
  17 #include <string.h>
  18 #include <assert.h>
  19
  20 #include "raop.h"
  21 #include "raop_rtp.h"
  22 #include "rsakey.h"
  23 #include "digest.h"
  24 #include "httpd.h"
  25 #include "sdp.h"
  26
  27 #include "global.h"
  28 #include "utils.h"
  29 #include "netutils.h"
  30 #include "logger.h"
  31 #include "compat.h"
  32
  33 /* Actually 345 bytes for 2048-bit key */
  34 #define MAX_SIGNATURE_LEN 512
  35
  36 /* Let's just decide on some length */
  37 #define MAX_PASSWORD_LEN 64
  38
  39 /* MD5 as hex fits here */
  40 #define MAX_NONCE_LEN 32
  41
  42 struct raop_s {
  43         /* Callbacks for audio */
  44         raop_callbacks_t callbacks;
  45
  46         /* Logger instance */
  47         logger_t *logger;
  48
  49         /* HTTP daemon and RSA key */
  50         httpd_t *httpd;
  51         rsakey_t *rsakey;
  52
  53         /* Hardware address information */
  54         unsigned char hwaddr[MAX_HWADDR_LEN];
  55         int hwaddrlen;
  56
  57         /* Password information */
  58         char password[MAX_PASSWORD_LEN+1];
  59 };
  60
  61 struct raop_conn_s {
  62         raop_t *raop;
  63         raop_rtp_t *raop_rtp;
  64
  65         unsigned char *local;
  66         int locallen;
  67
  68         unsigned char *remote;
  69         int remotelen;
  70
  71         char nonce[MAX_NONCE_LEN+1];
  72 };
  73 typedef struct raop_conn_s raop_conn_t;
  74
  75 static void *
  76 conn_init(void *opaque, unsigned char *local, int locallen, unsigned char *remote, int remotelen)
  77 {
  78         raop_conn_t *conn;
  79
  80         conn = calloc(1, sizeof(raop_conn_t));
  81         if (!conn) {
  82                 return NULL;
  83         }
  84         conn->raop = opaque;
  85         conn->raop_rtp = NULL;
  86
  87         if (locallen == 4) {
  88                 logger_log(conn->raop->logger, LOGGER_INFO,
  89                            "Local: %d.%d.%d.%d",
  90                            local[0], local[1], local[2], local[3]);
  91         } else if (locallen == 16) {
  92                 logger_log(conn->raop->logger, LOGGER_INFO,
  93                            "Local: %02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x",
  94                            local[0], local[1], local[2], local[3], local[4], local[5], local[6], local[7],
  95                            local[8], local[9], local[10], local[11], local[12], local[13], local[14], local[15]);
  96         }
  97         if (remotelen == 4) {
  98                 logger_log(conn->raop->logger, LOGGER_INFO,
  99                            "Remote: %d.%d.%d.%d",
 100                            remote[0], remote[1], remote[2], remote[3]);
 101         } else if (remotelen == 16) {
 102                 logger_log(conn->raop->logger, LOGGER_INFO,
 103                            "Remote: %02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x",
 104                            remote[0], remote[1], remote[2], remote[3], remote[4], remote[5], remote[6], remote[7],
 105                            remote[8], remote[9], remote[10], remote[11], remote[12], remote[13], remote[14], remote[15]);
 106         }
 107
 108         conn->local = malloc(locallen);
 109         assert(conn->local);
 110         memcpy(conn->local, local, locallen);
 111
 112         conn->remote = malloc(remotelen);
 113         assert(conn->remote);
 114         memcpy(conn->remote, remote, remotelen);
 115
 116         conn->locallen = locallen;
 117         conn->remotelen = remotelen;
 118
 119         digest_generate_nonce(conn->nonce, sizeof(conn->nonce));
 120         return conn;
 121 }
 122
 123 static void
 124 conn_request(void *ptr, http_request_t *request, http_response_t **response)
 125 {
 126 <<<<<<< HEAD
 127 =======
 128         const char realm[] = "airplay";
 129 >>>>>>> 64d59e3087f829006d091fa0d114efb50972a2bf
 130         raop_conn_t *conn = ptr;
 131         raop_t *raop = conn->raop;
 132
 133         http_response_t *res;
 134         const char *method;
 135         const char *cseq;
 136         const char *challenge;
 137         int require_auth = 0;
 138
 139         method = http_request_get_method(request);
 140         cseq = http_request_get_header(request, "CSeq");
 141         if (!method || !cseq) {
 142                 return;
 143         }
 144
 145         res = http_response_init("RTSP/1.0", 200, "OK");
 146 <<<<<<< HEAD
 147         if (strlen(raop->password)) {
 148 =======
 149
 150         /* We need authorization for everything else than OPTIONS request */
 151         if (strcmp(method, "OPTIONS") != 0 && strlen(raop->password)) {
 152 >>>>>>> 64d59e3087f829006d091fa0d114efb50972a2bf
 153                 const char *authorization;
 154
 155                 authorization = http_request_get_header(request, "Authorization");
 156                 if (authorization) {
 157                         logger_log(conn->raop->logger, LOGGER_DEBUG, "Our nonce: %s", conn->nonce);
 158                         logger_log(conn->raop->logger, LOGGER_DEBUG, "Authorization: %s", authorization);
 159                 }
 160 <<<<<<< HEAD
 161                 if (!digest_is_valid("AppleTV", raop->password, conn->nonce, method, http_request_get_url(request), authorization)) {
 162 =======
 163                 if (!digest_is_valid(realm, raop->password, conn->nonce, method, http_request_get_url(request), authorization)) {
 164 >>>>>>> 64d59e3087f829006d091fa0d114efb50972a2bf
 165                         char *authstr;
 166                         int authstrlen;
 167
 168                         /* Allocate the authenticate string */
 169 <<<<<<< HEAD
 170                         authstrlen = sizeof("Digest realm=\"AppleTV\", nonce=\"\"") + sizeof(conn->nonce) + 1;
 171 =======
 172                         authstrlen = sizeof("Digest realm=\"\", nonce=\"\"") + sizeof(realm) + sizeof(conn->nonce) + 1;
 173 >>>>>>> 64d59e3087f829006d091fa0d114efb50972a2bf
 174                         authstr = malloc(authstrlen);
 175
 176                         /* Concatenate the authenticate string */
 177                         memset(authstr, 0, authstrlen);
 178 <<<<<<< HEAD
 179                         strcat(authstr, "Digest realm=\"AppleTV\", nonce=\"");
 180 =======
 181                         strcat(authstr, "Digest realm=\"");
 182                         strcat(authstr, realm);
 183                         strcat(authstr, "\", nonce=\"");
 184 >>>>>>> 64d59e3087f829006d091fa0d114efb50972a2bf
 185                         strcat(authstr, conn->nonce);
 186                         strcat(authstr, "\"");
 187
 188                         /* Construct a new response */
 189                         require_auth = 1;
 190                         http_response_destroy(res);
 191                         res = http_response_init("RTSP/1.0", 401, "Unauthorized");
 192                         http_response_add_header(res, "WWW-Authenticate", authstr);
 193                         free(authstr);
 194                         logger_log(conn->raop->logger, LOGGER_DEBUG, "Authentication unsuccessful, sending Unauthorized");
 195                 } else {
 196                         logger_log(conn->raop->logger, LOGGER_DEBUG, "Authentication successful!");
 197                 }
 198         }
 199
 200         http_response_add_header(res, "CSeq", cseq);
 201         http_response_add_header(res, "Apple-Jack-Status", "connected; type=analog");
 202
 203         challenge = http_request_get_header(request, "Apple-Challenge");
 204         if (!require_auth && challenge) {
 205                 char signature[MAX_SIGNATURE_LEN];
 206
 207                 memset(signature, 0, sizeof(signature));
 208                 rsakey_sign(raop->rsakey, signature, sizeof(signature), challenge,
 209                             conn->local, conn->locallen, raop->hwaddr, raop->hwaddrlen);
 210                 http_response_add_header(res, "Apple-Response", signature);
 211
 212                 logger_log(conn->raop->logger, LOGGER_DEBUG, "Got challenge: %s", challenge);
 213                 logger_log(conn->raop->logger, LOGGER_DEBUG, "Got response: %s", signature);
 214         }
 215
 216         if (require_auth) {
 217                 /* Do nothing in case of authentication request */
 218         } else if (!strcmp(method, "OPTIONS")) {
 219                 http_response_add_header(res, "Public", "ANNOUNCE, SETUP, RECORD, PAUSE, FLUSH, TEARDOWN, OPTIONS, GET_PARAMETER, SET_PARAMETER");
 220         } else if (!strcmp(method, "ANNOUNCE")) {
 221                 const char *data;
 222                 int datalen;
 223
 224                 unsigned char aeskey[16];
 225                 unsigned char aesiv[16];
 226                 int aeskeylen, aesivlen;
 227
 228                 data = http_request_get_data(request, &datalen);
 229                 if (data) {
 230                         sdp_t *sdp;
 231                         const char *remotestr, *rtpmapstr, *fmtpstr, *aeskeystr, *aesivstr;
 232
 233                         sdp = sdp_init(data, datalen);
 234                         remotestr = sdp_get_connection(sdp);
 235                         rtpmapstr = sdp_get_rtpmap(sdp);
 236                         fmtpstr = sdp_get_fmtp(sdp);
 237                         aeskeystr = sdp_get_rsaaeskey(sdp);
 238                         aesivstr = sdp_get_aesiv(sdp);
 239
 240                         logger_log(conn->raop->logger, LOGGER_DEBUG, "connection: %s", remotestr);
 241                         logger_log(conn->raop->logger, LOGGER_DEBUG, "rtpmap: %s", rtpmapstr);
 242                         logger_log(conn->raop->logger, LOGGER_DEBUG, "fmtp: %s", fmtpstr);
 243                         logger_log(conn->raop->logger, LOGGER_DEBUG, "rsaaeskey: %s", aeskeystr);
 244                         logger_log(conn->raop->logger, LOGGER_DEBUG, "aesiv: %s", aesivstr);
 245
 246                         aeskeylen = rsakey_decrypt(raop->rsakey, aeskey, sizeof(aeskey), aeskeystr);
 247                         aesivlen = rsakey_parseiv(raop->rsakey, aesiv, sizeof(aesiv), aesivstr);
 248                         logger_log(conn->raop->logger, LOGGER_DEBUG, "aeskeylen: %d", aeskeylen);
 249                         logger_log(conn->raop->logger, LOGGER_DEBUG, "aesivlen: %d", aesivlen);
 250
 251                         if (conn->raop_rtp) {
 252                                 /* This should never happen */
 253                                 raop_rtp_destroy(conn->raop_rtp);
 254                                 conn->raop_rtp = NULL;
 255                         }
 256                         conn->raop_rtp = raop_rtp_init(raop->logger, &raop->callbacks, remotestr, rtpmapstr, fmtpstr, aeskey, aesiv);
 257                         if (!conn->raop_rtp) {
 258                                 logger_log(conn->raop->logger, LOGGER_ERR, "Error initializing the audio decoder");
 259                                 http_response_set_disconnect(res, 1);
 260                         }
 261                         sdp_destroy(sdp);
 262                 }
 263         } else if (!strcmp(method, "SETUP")) {
 264                 unsigned short remote_cport=0, remote_tport=0;
 265                 unsigned short cport=0, tport=0, dport=0;
 266                 const char *transport;
 267                 char buffer[1024];
 268                 int use_udp;
 269
 270                 transport = http_request_get_header(request, "Transport");
 271                 assert(transport);
 272
 273                 logger_log(conn->raop->logger, LOGGER_INFO, "Transport: %s", transport);
 274                 use_udp = strncmp(transport, "RTP/AVP/TCP", 11);
 275                 if (use_udp) {
 276                         char *original, *current, *tmpstr;
 277
 278                         current = original = strdup(transport);
 279                         if (original) {
 280                                 while ((tmpstr = utils_strsep(&current, ";")) != NULL) {
 281                                         unsigned short value;
 282                                         int ret;
 283
 284                                         ret = sscanf(tmpstr, "control_port=%hu", &value);
 285                                         if (ret == 1) {
 286                                                 logger_log(conn->raop->logger, LOGGER_DEBUG, "Found remote control port: %hu", value);
 287                                                 remote_cport = value;
 288                                         }
 289                                         ret = sscanf(tmpstr, "timing_port=%hu", &value);
 290                                         if (ret == 1) {
 291                                                 logger_log(conn->raop->logger, LOGGER_DEBUG, "Found remote timing port: %hu", value);
 292                                                 remote_tport = value;
 293                                         }
 294                                 }
 295                         }
 296                         free(original);
 297                 }
 298                 if (conn->raop_rtp) {
 299                         raop_rtp_start(conn->raop_rtp, use_udp, remote_cport, remote_tport, &cport, &tport, &dport);
 300                 } else {
 301                         logger_log(conn->raop->logger, LOGGER_ERR, "RAOP not initialized at SETUP, playing will fail!");
 302                         http_response_set_disconnect(res, 1);
 303                 }
 304
 305                 memset(buffer, 0, sizeof(buffer));
 306                 if (use_udp) {
 307                         snprintf(buffer, sizeof(buffer)-1,
 308                                  "RTP/AVP/UDP;unicast;mode=record;timing_port=%hu;events;control_port=%hu;server_port=%hu",
 309                                  tport, cport, dport);
 310                 } else {
 311                         snprintf(buffer, sizeof(buffer)-1,
 312                                  "RTP/AVP/TCP;unicast;interleaved=0-1;mode=record;server_port=%u",
 313                                  dport);
 314                 }
 315                 logger_log(conn->raop->logger, LOGGER_INFO, "Responding with %s", buffer);
 316                 http_response_add_header(res, "Transport", buffer);
 317                 http_response_add_header(res, "Session", "DEADBEEF");
 318         } else if (!strcmp(method, "SET_PARAMETER")) {
 319                 const char *content_type;
 320                 const char *data;
 321                 int datalen;
 322
 323                 content_type = http_request_get_header(request, "Content-Type");
 324                 data = http_request_get_data(request, &datalen);
 325                 if (!strcmp(content_type, "text/parameters")) {
 326                         char *datastr;
 327                         datastr = calloc(1, datalen+1);
 328                         if (data && datastr && conn->raop_rtp) {
 329                                 memcpy(datastr, data, datalen);
 330                                 if (!strncmp(datastr, "volume: ", 8)) {
 331                                         float vol = 0.0;
 332                                         sscanf(datastr+8, "%f", &vol);
 333                                         raop_rtp_set_volume(conn->raop_rtp, vol);
 334                                 }
 335                         } else if (!conn->raop_rtp) {
 336                                 logger_log(conn->raop->logger, LOGGER_WARNING, "RAOP not initialized at SET_PARAMETER volume");
 337                         }
 338                         free(datastr);
 339                 } else if (!strcmp(content_type, "image/jpeg")) {
 340                         logger_log(conn->raop->logger, LOGGER_INFO, "Got image data of %d bytes", datalen);
 341                         if (conn->raop_rtp) {
 342                                 raop_rtp_set_coverart(conn->raop_rtp, data, datalen);
 343                         } else {
 344                                 logger_log(conn->raop->logger, LOGGER_WARNING, "RAOP not initialized at SET_PARAMETER coverart");
 345                         }
 346                 } else if (!strcmp(content_type, "application/x-dmap-tagged")) {
 347                         logger_log(conn->raop->logger, LOGGER_INFO, "Got metadata of %d bytes", datalen);
 348                         if (conn->raop_rtp) {
 349                                 raop_rtp_set_metadata(conn->raop_rtp, data, datalen);
 350                         } else {
 351                                 logger_log(conn->raop->logger, LOGGER_WARNING, "RAOP not initialized at SET_PARAMETER metadata");
 352                         }
 353                 }
 354         } else if (!strcmp(method, "FLUSH")) {
 355                 const char *rtpinfo;
 356                 int next_seq = -1;
 357
 358                 rtpinfo = http_request_get_header(request, "RTP-Info");
 359                 if (rtpinfo) {
 360                         logger_log(conn->raop->logger, LOGGER_INFO, "Flush with RTP-Info: %s", rtpinfo);
 361                         if (!strncmp(rtpinfo, "seq=", 4)) {
 362                                 next_seq = strtol(rtpinfo+4, NULL, 10);
 363                         }
 364                 }
 365                 if (conn->raop_rtp) {
 366                         raop_rtp_flush(conn->raop_rtp, next_seq);
 367                 } else {
 368                         logger_log(conn->raop->logger, LOGGER_WARNING, "RAOP not initialized at FLUSH");
 369                 }
 370         } else if (!strcmp(method, "TEARDOWN")) {
 371                 http_response_add_header(res, "Connection", "close");
 372                 if (conn->raop_rtp) {
 373                         /* Destroy our RTP session */
 374                         raop_rtp_stop(conn->raop_rtp);
 375                         raop_rtp_destroy(conn->raop_rtp);
 376                         conn->raop_rtp = NULL;
 377                 }
 378         }
 379         http_response_finish(res, NULL, 0);
 380
 381         logger_log(conn->raop->logger, LOGGER_DEBUG, "Handled request %s with URL %s", method, http_request_get_url(request));
 382         *response = res;
 383 }
 384
 385 static void
 386 conn_destroy(void *ptr)
 387 {
 388         raop_conn_t *conn = ptr;
 389
 390         if (conn->raop_rtp) {
 391                 /* This is done in case TEARDOWN was not called */
 392                 raop_rtp_destroy(conn->raop_rtp);
 393         }
 394         free(conn->local);
 395         free(conn->remote);
 396         free(conn);
 397 }
 398
 399 raop_t *
 400 raop_init(int max_clients, raop_callbacks_t *callbacks, const char *pemkey, int *error)
 401 {
 402         raop_t *raop;
 403         httpd_t *httpd;
 404         rsakey_t *rsakey;
 405         httpd_callbacks_t httpd_cbs;
 406
 407         assert(callbacks);
 408         assert(max_clients > 0);
 409         assert(max_clients < 100);
 410         assert(pemkey);
 411
 412         /* Initialize the network */
 413         if (netutils_init() < 0) {
 414                 return NULL;
 415         }
 416
 417         /* Validate the callbacks structure */
 418         if (!callbacks->audio_init ||
 419             !callbacks->audio_process ||
 420             !callbacks->audio_destroy) {
 421                 return NULL;
 422         }
 423
 424         /* Allocate the raop_t structure */
 425         raop = calloc(1, sizeof(raop_t));
 426         if (!raop) {
 427                 return NULL;
 428         }
 429
 430         /* Initialize the logger */
 431         raop->logger = logger_init();
 432
 433         /* Set HTTP callbacks to our handlers */
 434         memset(&httpd_cbs, 0, sizeof(httpd_cbs));
 435         httpd_cbs.opaque = raop;
 436         httpd_cbs.conn_init = &conn_init;
 437         httpd_cbs.conn_request = &conn_request;
 438         httpd_cbs.conn_destroy = &conn_destroy;
 439
 440         /* Initialize the http daemon */
 441         httpd = httpd_init(raop->logger, &httpd_cbs, max_clients);
 442         if (!httpd) {
 443                 free(raop);
 444                 return NULL;
 445         }
 446
 447         /* Copy callbacks structure */
 448         memcpy(&raop->callbacks, callbacks, sizeof(raop_callbacks_t));
 449
 450         /* Initialize RSA key handler */
 451         rsakey = rsakey_init_pem(pemkey);
 452         if (!rsakey) {
 453                 free(httpd);
 454                 free(raop);
 455                 return NULL;
 456         }
 457
 458         raop->httpd = httpd;
 459         raop->rsakey = rsakey;
 460
 461         return raop;
 462 }
 463
 464 raop_t *
 465 raop_init_from_keyfile(int max_clients, raop_callbacks_t *callbacks, const char *keyfile, int *error)
 466 {
 467         raop_t *raop;
 468         char *pemstr;
 469
 470         if (utils_read_file(&pemstr, keyfile) < 0) {
 471                 return NULL;
 472         }
 473         raop = raop_init(max_clients, callbacks, pemstr, error);
 474         free(pemstr);
 475         return raop;
 476 }
 477
 478 void
 479 raop_destroy(raop_t *raop)
 480 {
 481         if (raop) {
 482                 raop_stop(raop);
 483
 484                 httpd_destroy(raop->httpd);
 485                 rsakey_destroy(raop->rsakey);
 486                 logger_destroy(raop->logger);
 487                 free(raop);
 488
 489                 /* Cleanup the network */
 490                 netutils_cleanup();
 491         }
 492 }
 493
 494 int
 495 raop_is_running(raop_t *raop)
 496 {
 497         assert(raop);
 498
 499         return httpd_is_running(raop->httpd);
 500 }
 501
 502 void
 503 raop_set_log_level(raop_t *raop, int level)
 504 {
 505         assert(raop);
 506
 507         logger_set_level(raop->logger, level);
 508 }
 509
 510 void
 511 raop_set_log_callback(raop_t *raop, raop_log_callback_t callback, void *cls)
 512 {
 513         assert(raop);
 514
 515         logger_set_callback(raop->logger, callback, cls);
 516 }
 517
 518 int
 519 raop_start(raop_t *raop, unsigned short *port, const char *hwaddr, int hwaddrlen, const char *password)
 520 {
 521         assert(raop);
 522         assert(port);
 523         assert(hwaddr);
 524
 525         /* Validate hardware address */
 526         if (hwaddrlen > MAX_HWADDR_LEN) {
 527                 return -1;
 528         }
 529
 530         memset(raop->password, 0, sizeof(raop->password));
 531         if (password) {
 532                 /* Validate password */
 533                 if (strlen(password) > MAX_PASSWORD_LEN) {
 534                         return -1;
 535                 }
 536
 537                 /* Copy password to the raop structure */
 538                 strncpy(raop->password, password, MAX_PASSWORD_LEN);
 539         }
 540
 541         /* Copy hwaddr to the raop structure */
 542         memcpy(raop->hwaddr, hwaddr, hwaddrlen);
 543         raop->hwaddrlen = hwaddrlen;
 544
 545         return httpd_start(raop->httpd, port);
 546 }
 547
 548 void
 549 raop_stop(raop_t *raop)
 550 {
 551         assert(raop);
 552
 553         httpd_stop(raop->httpd);
 554 }
 555