code.delx.au - pulseaudio/blob - src/modules/rtp/raop_client.c

   1 /***
   2   This file is part of PulseAudio.
   3
   4   Copyright 2008 Colin Guthrie
   5
   6   PulseAudio is free software; you can redistribute it and/or modify
   7   it under the terms of the GNU Lesser General Public License as published
   8   by the Free Software Foundation; either version 2 of the License,
   9   or (at your option) any later version.
  10
  11   PulseAudio is distributed in the hope that it will be useful, but
  12   WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  14   General Public License for more details.
  15
  16   You should have received a copy of the GNU Lesser General Public License
  17   along with PulseAudio; if not, write to the Free Software
  18   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  19   USA.
  20 ***/
  21
  22 #ifdef HAVE_CONFIG_H
  23 #include <config.h>
  24 #endif
  25
  26 #include <fcntl.h>
  27 #include <stdlib.h>
  28 #include <string.h>
  29 #include <errno.h>
  30 #include <arpa/inet.h>
  31 #include <unistd.h>
  32 #include <sys/ioctl.h>
  33
  34 #ifdef HAVE_SYS_FILIO_H
  35 #include <sys/filio.h>
  36 #endif
  37
  38 /* TODO: Replace OpenSSL with NSS */
  39 #include <openssl/err.h>
  40 #include <openssl/rand.h>
  41 #include <openssl/aes.h>
  42 #include <openssl/rsa.h>
  43 #include <openssl/engine.h>
  44
  45 #include <pulse/xmalloc.h>
  46
  47 #include <pulsecore/core-error.h>
  48 #include <pulsecore/core-util.h>
  49 #include <pulsecore/socket-util.h>
  50 #include <pulsecore/log.h>
  51 #include <pulsecore/macro.h>
  52 #include <pulsecore/strbuf.h>
  53 #include <pulsecore/random.h>
  54 #include <pulsecore/poll.h>
  55
  56 #include "raop_client.h"
  57 #include "rtsp_client.h"
  58 #include "base64.h"
  59
  60 #define AES_CHUNKSIZE 16
  61
  62 #define JACK_STATUS_DISCONNECTED 0
  63 #define JACK_STATUS_CONNECTED 1
  64
  65 #define JACK_TYPE_ANALOG 0
  66 #define JACK_TYPE_DIGITAL 1
  67
  68 #define VOLUME_DEF -30
  69 #define VOLUME_MIN -144
  70 #define VOLUME_MAX 0
  71
  72
  73 struct pa_raop_client {
  74     pa_core *core;
  75     char *host;
  76     char *sid;
  77     pa_rtsp_client *rtsp;
  78
  79     uint8_t jack_type;
  80     uint8_t jack_status;
  81
  82     /* Encryption Related bits */
  83     AES_KEY aes;
  84     uint8_t aes_iv[AES_CHUNKSIZE]; /* initialization vector for aes-cbc */
  85     uint8_t aes_nv[AES_CHUNKSIZE]; /* next vector for aes-cbc */
  86     uint8_t aes_key[AES_CHUNKSIZE]; /* key for aes-cbc */
  87
  88     pa_socket_client *sc;
  89     int fd;
  90
  91     uint16_t seq;
  92     uint32_t rtptime;
  93
  94     pa_raop_client_cb_t callback;
  95     void* userdata;
  96     pa_raop_client_closed_cb_t closed_callback;
  97     void* closed_userdata;
  98 };
  99
 100 /**
 101  * Function to write bits into a buffer.
 102  * @param buffer Handle to the buffer. It will be incremented if new data requires it.
 103  * @param bit_pos A pointer to a position buffer to keep track the current write location (0 for MSB, 7 for LSB)
 104  * @param size A pointer to the byte size currently written. This allows the calling function to do simple buffer overflow checks
 105  * @param data The data to write
 106  * @param data_bit_len The number of bits from data to write
 107  */
 108 static inline void bit_writer(uint8_t **buffer, uint8_t *bit_pos, int *size, uint8_t data, uint8_t data_bit_len) {
 109     int bits_left, bit_overflow;
 110     uint8_t bit_data;
 111
 112     if (!data_bit_len)
 113         return;
 114
 115     /* If bit pos is zero, we will definatly use at least one bit from the current byte so size increments. */
 116     if (!*bit_pos)
 117         *size += 1;
 118
 119     /* Calc the number of bits left in the current byte of buffer */
 120     bits_left = 7 - *bit_pos  + 1;
 121     /* Calc the overflow of bits in relation to how much space we have left... */
 122     bit_overflow = bits_left - data_bit_len;
 123     if (bit_overflow >= 0) {
 124         /* We can fit the new data in our current byte */
 125         /* As we write from MSB->LSB we need to left shift by the overflow amount */
 126         bit_data = data << bit_overflow;
 127         if (*bit_pos)
 128             **buffer |= bit_data;
 129         else
 130             **buffer = bit_data;
 131         /* If our data fits exactly into the current byte, we need to increment our pointer */
 132         if (0 == bit_overflow) {
 133             /* Do not increment size as it will be incremeneted on next call as bit_pos is zero */
 134             *buffer += 1;
 135             *bit_pos = 0;
 136         } else {
 137             *bit_pos += data_bit_len;
 138         }
 139     } else {
 140         /* bit_overflow is negative, there for we will need a new byte from our buffer */
 141         /* Firstly fill up what's left in the current byte */
 142         bit_data = data >> -bit_overflow;
 143         **buffer |= bit_data;
 144         /* Increment our buffer pointer and size counter*/
 145         *buffer += 1;
 146         *size += 1;
 147         **buffer = data << (8 + bit_overflow);
 148         *bit_pos = -bit_overflow;
 149     }
 150 }
 151
 152 static int rsa_encrypt(uint8_t *text, int len, uint8_t *res) {
 153     const char n[] =
 154         "59dE8qLieItsH1WgjrcFRKj6eUWqi+bGLOX1HL3U3GhC/j0Qg90u3sG/1CUtwC"
 155         "5vOYvfDmFI6oSFXi5ELabWJmT2dKHzBJKa3k9ok+8t9ucRqMd6DZHJ2YCCLlDR"
 156         "KSKv6kDqnw4UwPdpOMXziC/AMj3Z/lUVX1G7WSHCAWKf1zNS1eLvqr+boEjXuB"
 157         "OitnZ/bDzPHrTOZz0Dew0uowxf/+sG+NCK3eQJVxqcaJ/vEHKIVd2M+5qL71yJ"
 158         "Q+87X6oV3eaYvt3zWZYD6z5vYTcrtij2VZ9Zmni/UAaHqn9JdsBWLUEpVviYnh"
 159         "imNVvYFZeCXg/IdTQ+x4IRdiXNv5hEew==";
 160     const char e[] = "AQAB";
 161     uint8_t modules[256];
 162     uint8_t exponent[8];
 163     int size;
 164     RSA *rsa;
 165
 166     rsa = RSA_new();
 167     size = pa_base64_decode(n, modules);
 168     rsa->n = BN_bin2bn(modules, size, NULL);
 169     size = pa_base64_decode(e, exponent);
 170     rsa->e = BN_bin2bn(exponent, size, NULL);
 171
 172     size = RSA_public_encrypt(len, text, res, rsa, RSA_PKCS1_OAEP_PADDING);
 173     RSA_free(rsa);
 174     return size;
 175 }
 176
 177 static int aes_encrypt(pa_raop_client* c, uint8_t *data, int size)
 178 {
 179     uint8_t *buf;
 180     int i=0, j;
 181
 182     pa_assert(c);
 183
 184     memcpy(c->aes_nv, c->aes_iv, AES_CHUNKSIZE);
 185     while (i+AES_CHUNKSIZE <= size) {
 186         buf = data + i;
 187         for (j=0; j<AES_CHUNKSIZE; ++j)
 188             buf[j] ^= c->aes_nv[j];
 189
 190         AES_encrypt(buf, buf, &c->aes);
 191         memcpy(c->aes_nv, buf, AES_CHUNKSIZE);
 192         i += AES_CHUNKSIZE;
 193     }
 194     return i;
 195 }
 196
 197 static inline void rtrimchar(char *str, char rc)
 198 {
 199     char *sp = str + strlen(str) - 1;
 200     while (sp >= str && *sp == rc) {
 201         *sp = '\0';
 202         sp -= 1;
 203     }
 204 }
 205
 206 static void on_connection(pa_socket_client *sc, pa_iochannel *io, void *userdata) {
 207     pa_raop_client *c = userdata;
 208
 209     pa_assert(sc);
 210     pa_assert(c);
 211     pa_assert(c->sc == sc);
 212     pa_assert(c->fd < 0);
 213     pa_assert(c->callback);
 214
 215     pa_socket_client_unref(c->sc);
 216     c->sc = NULL;
 217
 218     if (!io) {
 219         pa_log("Connection failed: %s", pa_cstrerror(errno));
 220         return;
 221     }
 222
 223     c->fd = pa_iochannel_get_send_fd(io);
 224
 225     pa_iochannel_set_noclose(io, TRUE);
 226     pa_iochannel_socket_set_sndbuf(io, 1024);
 227     pa_iochannel_free(io);
 228
 229     pa_make_tcp_socket_low_delay(c->fd);
 230
 231     pa_log_debug("Connection established");
 232     c->callback(c->fd, c->userdata);
 233 }
 234
 235 static void rtsp_cb(pa_rtsp_client *rtsp, pa_rtsp_state state, pa_headerlist* headers, void *userdata)
 236 {
 237     pa_raop_client* c = userdata;
 238     pa_assert(c);
 239     pa_assert(rtsp);
 240     pa_assert(rtsp == c->rtsp);
 241
 242     switch (state) {
 243         case STATE_CONNECT: {
 244             int i;
 245             uint8_t rsakey[512];
 246             char *key, *iv, *sac, *sdp;
 247             uint16_t rand_data;
 248             const char *ip;
 249             char *url;
 250
 251             pa_log_debug("RAOP: CONNECTED");
 252             ip = pa_rtsp_localip(c->rtsp);
 253             /* First of all set the url properly */
 254             url = pa_sprintf_malloc("rtsp://%s/%s", ip, c->sid);
 255             pa_rtsp_set_url(c->rtsp, url);
 256             pa_xfree(url);
 257
 258             /* Now encrypt our aes_public key to send to the device */
 259             i = rsa_encrypt(c->aes_key, AES_CHUNKSIZE, rsakey);
 260             pa_base64_encode(rsakey, i, &key);
 261             rtrimchar(key, '=');
 262             pa_base64_encode(c->aes_iv, AES_CHUNKSIZE, &iv);
 263             rtrimchar(iv, '=');
 264
 265             pa_random(&rand_data, sizeof(rand_data));
 266             pa_base64_encode(&rand_data, AES_CHUNKSIZE, &sac);
 267             rtrimchar(sac, '=');
 268             pa_rtsp_add_header(c->rtsp, "Apple-Challenge", sac);
 269             sdp = pa_sprintf_malloc(
 270                 "v=0\r\n"
 271                 "o=iTunes %s 0 IN IP4 %s\r\n"
 272                 "s=iTunes\r\n"
 273                 "c=IN IP4 %s\r\n"
 274                 "t=0 0\r\n"
 275                 "m=audio 0 RTP/AVP 96\r\n"
 276                 "a=rtpmap:96 AppleLossless\r\n"
 277                 "a=fmtp:96 4096 0 16 40 10 14 2 255 0 0 44100\r\n"
 278                 "a=rsaaeskey:%s\r\n"
 279                 "a=aesiv:%s\r\n",
 280                 c->sid, ip, c->host, key, iv);
 281             pa_rtsp_announce(c->rtsp, sdp);
 282             pa_xfree(key);
 283             pa_xfree(iv);
 284             pa_xfree(sac);
 285             pa_xfree(sdp);
 286             break;
 287         }
 288
 289         case STATE_ANNOUNCE:
 290             pa_log_debug("RAOP: ANNOUNCED");
 291             pa_rtsp_remove_header(c->rtsp, "Apple-Challenge");
 292             pa_rtsp_setup(c->rtsp);
 293             break;
 294
 295         case STATE_SETUP: {
 296             char *aj = pa_xstrdup(pa_headerlist_gets(headers, "Audio-Jack-Status"));
 297             pa_log_debug("RAOP: SETUP");
 298             if (aj) {
 299                 char *token, *pc;
 300                 char delimiters[] = ";";
 301                 const char* token_state = NULL;
 302                 c->jack_type = JACK_TYPE_ANALOG;
 303                 c->jack_status = JACK_STATUS_DISCONNECTED;
 304
 305                 while ((token = pa_split(aj, delimiters, &token_state))) {
 306                     if ((pc = strstr(token, "="))) {
 307                       *pc = 0;
 308                       if (!strcmp(token, "type") && !strcmp(pc+1, "digital")) {
 309                           c->jack_type = JACK_TYPE_DIGITAL;
 310                       }
 311                     } else {
 312                         if (!strcmp(token,"connected"))
 313                             c->jack_status = JACK_STATUS_CONNECTED;
 314                     }
 315                     pa_xfree(token);
 316                 }
 317                 pa_xfree(aj);
 318             } else {
 319                 pa_log_warn("Audio Jack Status missing");
 320             }
 321             pa_rtsp_record(c->rtsp, &c->seq, &c->rtptime);
 322             break;
 323         }
 324
 325         case STATE_RECORD: {
 326             uint32_t port = pa_rtsp_serverport(c->rtsp);
 327             pa_log_debug("RAOP: RECORDED");
 328
 329             if (!(c->sc = pa_socket_client_new_string(c->core->mainloop, c->host, port))) {
 330                 pa_log("failed to connect to server '%s:%d'", c->host, port);
 331                 return;
 332             }
 333             pa_socket_client_set_callback(c->sc, on_connection, c);
 334             break;
 335         }
 336
 337         case STATE_FLUSH:
 338             pa_log_debug("RAOP: FLUSHED");
 339             break;
 340
 341         case STATE_TEARDOWN:
 342         case STATE_SET_PARAMETER:
 343             pa_log_debug("RAOP: SET_PARAMETER");
 344             break;
 345         case STATE_DISCONNECTED:
 346             pa_assert(c->closed_callback);
 347             pa_assert(c->rtsp);
 348
 349             pa_log_debug("RTSP control channel closed");
 350             pa_rtsp_client_free(c->rtsp);
 351             c->rtsp = NULL;
 352             if (c->fd > 0) {
 353                 /* We do not close the fd, we leave it to the closed callback to do that */
 354                 c->fd = -1;
 355             }
 356             if (c->sc) {
 357                 pa_socket_client_unref(c->sc);
 358                 c->sc = NULL;
 359             }
 360             pa_xfree(c->sid);
 361             c->sid = NULL;
 362             c->closed_callback(c->closed_userdata);
 363             break;
 364     }
 365 }
 366
 367 pa_raop_client* pa_raop_client_new(pa_core *core, const char* host)
 368 {
 369     pa_raop_client* c = pa_xnew0(pa_raop_client, 1);
 370
 371     pa_assert(core);
 372     pa_assert(host);
 373
 374     c->core = core;
 375     c->fd = -1;
 376     c->host = pa_xstrdup(host);
 377
 378     if (pa_raop_connect(c)) {
 379         pa_raop_client_free(c);
 380         return NULL;
 381     }
 382     return c;
 383 }
 384
 385
 386 void pa_raop_client_free(pa_raop_client* c)
 387 {
 388     pa_assert(c);
 389
 390     if (c->rtsp)
 391         pa_rtsp_client_free(c->rtsp);
 392     pa_xfree(c->host);
 393     pa_xfree(c);
 394 }
 395
 396
 397 int pa_raop_connect(pa_raop_client* c)
 398 {
 399     char *sci;
 400     struct {
 401         uint32_t a;
 402         uint32_t b;
 403         uint32_t c;
 404     } rand_data;
 405
 406     pa_assert(c);
 407
 408     if (c->rtsp) {
 409         pa_log_debug("Connection already in progress");
 410         return 0;
 411     }
 412
 413     c->rtsp = pa_rtsp_client_new(c->core->mainloop, c->host, 5000, "iTunes/4.6 (Macintosh; U; PPC Mac OS X 10.3)");
 414
 415     /* Initialise the AES encryption system */
 416     pa_random(c->aes_iv, sizeof(c->aes_iv));
 417     pa_random(c->aes_key, sizeof(c->aes_key));
 418     memcpy(c->aes_nv, c->aes_iv, sizeof(c->aes_nv));
 419     AES_set_encrypt_key(c->aes_key, 128, &c->aes);
 420
 421     /* Generate random instance id */
 422     pa_random(&rand_data, sizeof(rand_data));
 423     c->sid = pa_sprintf_malloc("%u", rand_data.a);
 424     sci = pa_sprintf_malloc("%08x%08x",rand_data.b, rand_data.c);
 425     pa_rtsp_add_header(c->rtsp, "Client-Instance", sci);
 426     pa_xfree(sci);
 427     pa_rtsp_set_callback(c->rtsp, rtsp_cb, c);
 428     return pa_rtsp_connect(c->rtsp);
 429 }
 430
 431
 432 int pa_raop_flush(pa_raop_client* c)
 433 {
 434     pa_assert(c);
 435
 436     pa_rtsp_flush(c->rtsp, c->seq, c->rtptime);
 437     return 0;
 438 }
 439
 440
 441 int pa_raop_client_set_volume(pa_raop_client* c, pa_volume_t volume)
 442 {
 443     int rv;
 444     double db;
 445     char *param;
 446
 447     pa_assert(c);
 448
 449     db = pa_sw_volume_to_dB(volume);
 450     if (db < VOLUME_MIN)
 451         db = VOLUME_MIN;
 452     else if (db > VOLUME_MAX)
 453         db = VOLUME_MAX;
 454
 455     param = pa_sprintf_malloc("volume: %0.6f\r\n",  db);
 456
 457     /* We just hit and hope, cannot wait for the callback */
 458     rv = pa_rtsp_setparameter(c->rtsp, param);
 459     pa_xfree(param);
 460     return rv;
 461 }
 462
 463
 464 int pa_raop_client_encode_sample(pa_raop_client* c, pa_memchunk* raw, pa_memchunk* encoded)
 465 {
 466     uint16_t len;
 467     size_t bufmax;
 468     uint8_t *bp, bpos;
 469     uint8_t *ibp, *maxibp;
 470     int size;
 471     uint8_t *b, *p;
 472     uint32_t bsize;
 473     size_t length;
 474     static uint8_t header[] = {
 475         0x24, 0x00, 0x00, 0x00,
 476         0xF0, 0xFF, 0x00, 0x00,
 477         0x00, 0x00, 0x00, 0x00,
 478         0x00, 0x00, 0x00, 0x00,
 479     };
 480     int header_size = sizeof(header);
 481
 482     pa_assert(c);
 483     pa_assert(c->fd > 0);
 484     pa_assert(raw);
 485     pa_assert(raw->memblock);
 486     pa_assert(raw->length > 0);
 487     pa_assert(encoded);
 488
 489     /* We have to send 4 byte chunks */
 490     bsize = (int)(raw->length / 4);
 491     length = bsize * 4;
 492
 493     /* Leave 16 bytes extra to allow for the ALAC header which is about 55 bits */
 494     bufmax = length + header_size + 16;
 495     pa_memchunk_reset(encoded);
 496     encoded->memblock = pa_memblock_new(c->core->mempool, bufmax);
 497     b = pa_memblock_acquire(encoded->memblock);
 498     memcpy(b, header, header_size);
 499
 500     /* Now write the actual samples */
 501     bp = b + header_size;
 502     size = bpos = 0;
 503     bit_writer(&bp,&bpos,&size,1,3); /* channel=1, stereo */
 504     bit_writer(&bp,&bpos,&size,0,4); /* unknown */
 505     bit_writer(&bp,&bpos,&size,0,8); /* unknown */
 506     bit_writer(&bp,&bpos,&size,0,4); /* unknown */
 507     bit_writer(&bp,&bpos,&size,1,1); /* hassize */
 508     bit_writer(&bp,&bpos,&size,0,2); /* unused */
 509     bit_writer(&bp,&bpos,&size,1,1); /* is-not-compressed */
 510
 511     /* size of data, integer, big endian */
 512     bit_writer(&bp,&bpos,&size,(bsize>>24)&0xff,8);
 513     bit_writer(&bp,&bpos,&size,(bsize>>16)&0xff,8);
 514     bit_writer(&bp,&bpos,&size,(bsize>>8)&0xff,8);
 515     bit_writer(&bp,&bpos,&size,(bsize)&0xff,8);
 516
 517     ibp = p = pa_memblock_acquire(raw->memblock);
 518     maxibp = p + raw->length - 4;
 519     while (ibp <= maxibp) {
 520         /* Byte swap stereo data */
 521         bit_writer(&bp,&bpos,&size,*(ibp+1),8);
 522         bit_writer(&bp,&bpos,&size,*(ibp+0),8);
 523         bit_writer(&bp,&bpos,&size,*(ibp+3),8);
 524         bit_writer(&bp,&bpos,&size,*(ibp+2),8);
 525         ibp += 4;
 526         raw->index += 4;
 527         raw->length -= 4;
 528     }
 529     pa_memblock_release(raw->memblock);
 530     encoded->length = header_size + size;
 531
 532     /* store the lenght (endian swapped: make this better) */
 533     len = size + header_size - 4;
 534     *(b + 2) = len >> 8;
 535     *(b + 3) = len & 0xff;
 536
 537     /* encrypt our data */
 538     aes_encrypt(c, (b + header_size), size);
 539
 540     /* We're done with the chunk */
 541     pa_memblock_release(encoded->memblock);
 542
 543     return 0;
 544 }
 545
 546
 547 void pa_raop_client_set_callback(pa_raop_client* c, pa_raop_client_cb_t callback, void *userdata)
 548 {
 549     pa_assert(c);
 550
 551     c->callback = callback;
 552     c->userdata = userdata;
 553 }
 554
 555 void pa_raop_client_set_closed_callback(pa_raop_client* c, pa_raop_client_closed_cb_t callback, void *userdata)
 556 {
 557     pa_assert(c);
 558
 559     c->closed_callback = callback;
 560     c->closed_userdata = userdata;
 561 }