code.delx.au - pulseaudio/blob - src/modules/raop/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 2.1 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 <stdlib.h>
  27 #include <string.h>
  28 #include <errno.h>
  29 #include <unistd.h>
  30 #include <sys/ioctl.h>
  31
  32 #ifdef HAVE_SYS_FILIO_H
  33 #include <sys/filio.h>
  34 #endif
  35
  36 /* TODO: Replace OpenSSL with NSS */
  37 #include <openssl/err.h>
  38 #include <openssl/rand.h>
  39 #include <openssl/aes.h>
  40 #include <openssl/rsa.h>
  41 #include <openssl/engine.h>
  42
  43 #include <pulse/xmalloc.h>
  44
  45 #include <pulsecore/core-error.h>
  46 #include <pulsecore/core-util.h>
  47 #include <pulsecore/iochannel.h>
  48 #include <pulsecore/socket-util.h>
  49 #include <pulsecore/log.h>
  50 #include <pulsecore/parseaddr.h>
  51 #include <pulsecore/macro.h>
  52 #include <pulsecore/memchunk.h>
  53 #include <pulsecore/random.h>
  54
  55 #include "raop_client.h"
  56 #include "rtsp_client.h"
  57 #include "base64.h"
  58
  59 #define AES_CHUNKSIZE 16
  60
  61 #define JACK_STATUS_DISCONNECTED 0
  62 #define JACK_STATUS_CONNECTED 1
  63
  64 #define JACK_TYPE_ANALOG 0
  65 #define JACK_TYPE_DIGITAL 1
  66
  67 #define VOLUME_DEF -30
  68 #define VOLUME_MIN -144
  69 #define VOLUME_MAX 0
  70
  71 #define RAOP_PORT 5000
  72
  73 struct pa_raop_client {
  74     pa_core *core;
  75     char *host;
  76     uint16_t port;
  77     char *sid;
  78     pa_rtsp_client *rtsp;
  79
  80     uint8_t jack_type;
  81     uint8_t jack_status;
  82
  83     /* Encryption Related bits */
  84     AES_KEY aes;
  85     uint8_t aes_iv[AES_CHUNKSIZE]; /* initialization vector for aes-cbc */
  86     uint8_t aes_nv[AES_CHUNKSIZE]; /* next vector for aes-cbc */
  87     uint8_t aes_key[AES_CHUNKSIZE]; /* key for aes-cbc */
  88
  89     pa_socket_client *sc;
  90     int fd;
  91
  92     uint16_t seq;
  93     uint32_t rtptime;
  94
  95     pa_raop_client_cb_t callback;
  96     void* userdata;
  97     pa_raop_client_closed_cb_t closed_callback;
  98     void* closed_userdata;
  99 };
 100
 101 /**
 102  * Function to write bits into a buffer.
 103  * @param buffer Handle to the buffer. It will be incremented if new data requires it.
 104  * @param bit_pos A pointer to a position buffer to keep track the current write location (0 for MSB, 7 for LSB)
 105  * @param size A pointer to the byte size currently written. This allows the calling function to do simple buffer overflow checks
 106  * @param data The data to write
 107  * @param data_bit_len The number of bits from data to write
 108  */
 109 static inline void bit_writer(uint8_t **buffer, uint8_t *bit_pos, int *size, uint8_t data, uint8_t data_bit_len) {
 110     int bits_left, bit_overflow;
 111     uint8_t bit_data;
 112
 113     if (!data_bit_len)
 114         return;
 115
 116     /* If bit pos is zero, we will definately use at least one bit from the current byte so size increments. */
 117     if (!*bit_pos)
 118         *size += 1;
 119
 120     /* Calc the number of bits left in the current byte of buffer */
 121     bits_left = 7 - *bit_pos  + 1;
 122     /* Calc the overflow of bits in relation to how much space we have left... */
 123     bit_overflow = bits_left - data_bit_len;
 124     if (bit_overflow >= 0) {
 125         /* We can fit the new data in our current byte */
 126         /* As we write from MSB->LSB we need to left shift by the overflow amount */
 127         bit_data = data << bit_overflow;
 128         if (*bit_pos)
 129             **buffer |= bit_data;
 130         else
 131             **buffer = bit_data;
 132         /* If our data fits exactly into the current byte, we need to increment our pointer */
 133         if (0 == bit_overflow) {
 134             /* Do not increment size as it will be incremented on next call as bit_pos is zero */
 135             *buffer += 1;
 136             *bit_pos = 0;
 137         } else {
 138             *bit_pos += data_bit_len;
 139         }
 140     } else {
 141         /* bit_overflow is negative, there for we will need a new byte from our buffer */
 142         /* Firstly fill up what's left in the current byte */
 143         bit_data = data >> -bit_overflow;
 144         **buffer |= bit_data;
 145         /* Increment our buffer pointer and size counter*/
 146         *buffer += 1;
 147         *size += 1;
 148         **buffer = data << (8 + bit_overflow);
 149         *bit_pos = -bit_overflow;
 150     }
 151 }
 152
 153 static int rsa_encrypt(uint8_t *text, int len, uint8_t *res) {
 154     const char n[] =
 155         "59dE8qLieItsH1WgjrcFRKj6eUWqi+bGLOX1HL3U3GhC/j0Qg90u3sG/1CUtwC"
 156         "5vOYvfDmFI6oSFXi5ELabWJmT2dKHzBJKa3k9ok+8t9ucRqMd6DZHJ2YCCLlDR"
 157         "KSKv6kDqnw4UwPdpOMXziC/AMj3Z/lUVX1G7WSHCAWKf1zNS1eLvqr+boEjXuB"
 158         "OitnZ/bDzPHrTOZz0Dew0uowxf/+sG+NCK3eQJVxqcaJ/vEHKIVd2M+5qL71yJ"
 159         "Q+87X6oV3eaYvt3zWZYD6z5vYTcrtij2VZ9Zmni/UAaHqn9JdsBWLUEpVviYnh"
 160         "imNVvYFZeCXg/IdTQ+x4IRdiXNv5hEew==";
 161     const char e[] = "AQAB";
 162     uint8_t modules[256];
 163     uint8_t exponent[8];
 164     int size;
 165     RSA *rsa;
 166
 167     rsa = RSA_new();
 168     size = pa_base64_decode(n, modules);
 169     rsa->n = BN_bin2bn(modules, size, NULL);
 170     size = pa_base64_decode(e, exponent);
 171     rsa->e = BN_bin2bn(exponent, size, NULL);
 172
 173     size = RSA_public_encrypt(len, text, res, rsa, RSA_PKCS1_OAEP_PADDING);
 174     RSA_free(rsa);
 175     return size;
 176 }
 177
 178 static int aes_encrypt(pa_raop_client* c, uint8_t *data, int size) {
 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     char *sp = str + strlen(str) - 1;
 199     while (sp >= str && *sp == rc) {
 200         *sp = '\0';
 201         sp -= 1;
 202     }
 203 }
 204
 205 static void on_connection(pa_socket_client *sc, pa_iochannel *io, void *userdata) {
 206     pa_raop_client *c = userdata;
 207
 208     pa_assert(sc);
 209     pa_assert(c);
 210     pa_assert(c->sc == sc);
 211     pa_assert(c->fd < 0);
 212     pa_assert(c->callback);
 213
 214     pa_socket_client_unref(c->sc);
 215     c->sc = NULL;
 216
 217     if (!io) {
 218         pa_log("Connection failed: %s", pa_cstrerror(errno));
 219         return;
 220     }
 221
 222     c->fd = pa_iochannel_get_send_fd(io);
 223
 224     pa_iochannel_set_noclose(io, true);
 225     pa_iochannel_free(io);
 226
 227     pa_make_tcp_socket_low_delay(c->fd);
 228
 229     pa_log_debug("Connection established");
 230     c->callback(c->fd, c->userdata);
 231 }
 232
 233 static void rtsp_cb(pa_rtsp_client *rtsp, pa_rtsp_state state, pa_headerlist* headers, void *userdata) {
 234     pa_raop_client* c = userdata;
 235     pa_assert(c);
 236     pa_assert(rtsp);
 237     pa_assert(rtsp == c->rtsp);
 238
 239     switch (state) {
 240         case STATE_CONNECT: {
 241             int i;
 242             uint8_t rsakey[512];
 243             char *key, *iv, *sac, *sdp;
 244             uint16_t rand_data;
 245             const char *ip;
 246             char *url;
 247
 248             pa_log_debug("RAOP: CONNECTED");
 249             ip = pa_rtsp_localip(c->rtsp);
 250             /* First of all set the url properly */
 251             url = pa_sprintf_malloc("rtsp://%s/%s", ip, c->sid);
 252             pa_rtsp_set_url(c->rtsp, url);
 253             pa_xfree(url);
 254
 255             /* Now encrypt our aes_public key to send to the device */
 256             i = rsa_encrypt(c->aes_key, AES_CHUNKSIZE, rsakey);
 257             pa_base64_encode(rsakey, i, &key);
 258             rtrimchar(key, '=');
 259             pa_base64_encode(c->aes_iv, AES_CHUNKSIZE, &iv);
 260             rtrimchar(iv, '=');
 261
 262             pa_random(&rand_data, sizeof(rand_data));
 263             pa_base64_encode(&rand_data, AES_CHUNKSIZE, &sac);
 264             rtrimchar(sac, '=');
 265             pa_rtsp_add_header(c->rtsp, "Apple-Challenge", sac);
 266             sdp = pa_sprintf_malloc(
 267                 "v=0\r\n"
 268                 "o=iTunes %s 0 IN IP4 %s\r\n"
 269                 "s=iTunes\r\n"
 270                 "c=IN IP4 %s\r\n"
 271                 "t=0 0\r\n"
 272                 "m=audio 0 RTP/AVP 96\r\n"
 273                 "a=rtpmap:96 AppleLossless\r\n"
 274                 "a=fmtp:96 4096 0 16 40 10 14 2 255 0 0 44100\r\n"
 275                 "a=rsaaeskey:%s\r\n"
 276                 "a=aesiv:%s\r\n",
 277                 c->sid, ip, c->host, key, iv);
 278             pa_rtsp_announce(c->rtsp, sdp);
 279             pa_xfree(key);
 280             pa_xfree(iv);
 281             pa_xfree(sac);
 282             pa_xfree(sdp);
 283             break;
 284         }
 285
 286         case STATE_ANNOUNCE:
 287             pa_log_debug("RAOP: ANNOUNCED");
 288             pa_rtsp_remove_header(c->rtsp, "Apple-Challenge");
 289             pa_rtsp_setup(c->rtsp);
 290             break;
 291
 292         case STATE_SETUP: {
 293             char *aj = pa_xstrdup(pa_headerlist_gets(headers, "Audio-Jack-Status"));
 294             pa_log_debug("RAOP: SETUP");
 295             if (aj) {
 296                 char *token, *pc;
 297                 char delimiters[] = ";";
 298                 const char* token_state = NULL;
 299                 c->jack_type = JACK_TYPE_ANALOG;
 300                 c->jack_status = JACK_STATUS_DISCONNECTED;
 301
 302                 while ((token = pa_split(aj, delimiters, &token_state))) {
 303                     if ((pc = strstr(token, "="))) {
 304                       *pc = 0;
 305                       if (pa_streq(token, "type") && pa_streq(pc+1, "digital")) {
 306                           c->jack_type = JACK_TYPE_DIGITAL;
 307                       }
 308                     } else {
 309                         if (pa_streq(token, "connected"))
 310                             c->jack_status = JACK_STATUS_CONNECTED;
 311                     }
 312                     pa_xfree(token);
 313                 }
 314                 pa_xfree(aj);
 315             } else {
 316                 pa_log_warn("Audio Jack Status missing");
 317             }
 318             pa_rtsp_record(c->rtsp, &c->seq, &c->rtptime);
 319             break;
 320         }
 321
 322         case STATE_RECORD: {
 323             uint32_t port = pa_rtsp_serverport(c->rtsp);
 324             pa_log_debug("RAOP: RECORDED");
 325
 326             if (!(c->sc = pa_socket_client_new_string(c->core->mainloop, true, c->host, port))) {
 327                 pa_log("failed to connect to server '%s:%d'", c->host, port);
 328                 return;
 329             }
 330             pa_socket_client_set_callback(c->sc, on_connection, c);
 331             break;
 332         }
 333
 334         case STATE_FLUSH:
 335             pa_log_debug("RAOP: FLUSHED");
 336             break;
 337
 338         case STATE_TEARDOWN:
 339             pa_log_debug("RAOP: TEARDOWN");
 340             break;
 341
 342         case STATE_SET_PARAMETER:
 343             pa_log_debug("RAOP: SET_PARAMETER");
 344             break;
 345
 346         case STATE_DISCONNECTED:
 347             pa_assert(c->closed_callback);
 348             pa_assert(c->rtsp);
 349
 350             pa_log_debug("RTSP control channel closed");
 351             pa_rtsp_client_free(c->rtsp);
 352             c->rtsp = NULL;
 353             if (c->fd > 0) {
 354                 /* We do not close the fd, we leave it to the closed callback to do that */
 355                 c->fd = -1;
 356             }
 357             if (c->sc) {
 358                 pa_socket_client_unref(c->sc);
 359                 c->sc = NULL;
 360             }
 361             pa_xfree(c->sid);
 362             c->sid = NULL;
 363             c->closed_callback(c->closed_userdata);
 364             break;
 365     }
 366 }
 367
 368 pa_raop_client* pa_raop_client_new(pa_core *core, const char* host) {
 369     pa_parsed_address a;
 370     pa_raop_client* c = pa_xnew0(pa_raop_client, 1);
 371
 372     pa_assert(core);
 373     pa_assert(host);
 374
 375     if (pa_parse_address(host, &a) < 0 || a.type == PA_PARSED_ADDRESS_UNIX)
 376         return NULL;
 377
 378     c->core = core;
 379     c->fd = -1;
 380
 381     c->host = pa_xstrdup(a.path_or_host);
 382     if (a.port)
 383         c->port = a.port;
 384     else
 385         c->port = RAOP_PORT;
 386
 387     if (pa_raop_connect(c)) {
 388         pa_raop_client_free(c);
 389         return NULL;
 390     }
 391     return c;
 392 }
 393
 394 void pa_raop_client_free(pa_raop_client* c) {
 395     pa_assert(c);
 396
 397     if (c->rtsp)
 398         pa_rtsp_client_free(c->rtsp);
 399     if (c->sid)
 400         pa_xfree(c->sid);
 401     pa_xfree(c->host);
 402     pa_xfree(c);
 403 }
 404
 405 int pa_raop_connect(pa_raop_client* c) {
 406     char *sci;
 407     struct {
 408         uint32_t a;
 409         uint32_t b;
 410         uint32_t c;
 411     } rand_data;
 412
 413     pa_assert(c);
 414
 415     if (c->rtsp) {
 416         pa_log_debug("Connection already in progress");
 417         return 0;
 418     }
 419
 420     c->rtsp = pa_rtsp_client_new(c->core->mainloop, c->host, c->port, "iTunes/4.6 (Macintosh; U; PPC Mac OS X 10.3)");
 421
 422     /* Initialise the AES encryption system */
 423     pa_random(c->aes_iv, sizeof(c->aes_iv));
 424     pa_random(c->aes_key, sizeof(c->aes_key));
 425     memcpy(c->aes_nv, c->aes_iv, sizeof(c->aes_nv));
 426     AES_set_encrypt_key(c->aes_key, 128, &c->aes);
 427
 428     /* Generate random instance id */
 429     pa_random(&rand_data, sizeof(rand_data));
 430     c->sid = pa_sprintf_malloc("%u", rand_data.a);
 431     sci = pa_sprintf_malloc("%08x%08x",rand_data.b, rand_data.c);
 432     pa_rtsp_add_header(c->rtsp, "Client-Instance", sci);
 433     pa_xfree(sci);
 434     pa_rtsp_set_callback(c->rtsp, rtsp_cb, c);
 435     return pa_rtsp_connect(c->rtsp);
 436 }
 437
 438 int pa_raop_flush(pa_raop_client* c) {
 439     pa_assert(c);
 440
 441     pa_rtsp_flush(c->rtsp, c->seq, c->rtptime);
 442     return 0;
 443 }
 444
 445 int pa_raop_client_set_volume(pa_raop_client* c, pa_volume_t volume) {
 446     int rv;
 447     double db;
 448     char *param;
 449
 450     pa_assert(c);
 451
 452     db = pa_sw_volume_to_dB(volume);
 453     if (db < VOLUME_MIN)
 454         db = VOLUME_MIN;
 455     else if (db > VOLUME_MAX)
 456         db = VOLUME_MAX;
 457
 458     param = pa_sprintf_malloc("volume: %0.6f\r\n",  db);
 459
 460     /* We just hit and hope, cannot wait for the callback */
 461     rv = pa_rtsp_setparameter(c->rtsp, param);
 462     pa_xfree(param);
 463     return rv;
 464 }
 465
 466 int pa_raop_client_encode_sample(pa_raop_client* c, pa_memchunk* raw, pa_memchunk* encoded) {
 467     uint16_t len;
 468     size_t bufmax;
 469     uint8_t *bp, bpos;
 470     uint8_t *ibp, *maxibp;
 471     int size;
 472     uint8_t *b, *p;
 473     uint32_t bsize;
 474     size_t length;
 475     static uint8_t header[] = {
 476         0x24, 0x00, 0x00, 0x00,
 477         0xF0, 0xFF, 0x00, 0x00,
 478         0x00, 0x00, 0x00, 0x00,
 479         0x00, 0x00, 0x00, 0x00,
 480     };
 481     int header_size = sizeof(header);
 482
 483     pa_assert(c);
 484     pa_assert(c->fd > 0);
 485     pa_assert(raw);
 486     pa_assert(raw->memblock);
 487     pa_assert(raw->length > 0);
 488     pa_assert(encoded);
 489
 490     /* We have to send 4 byte chunks */
 491     bsize = (int)(raw->length / 4);
 492     length = bsize * 4;
 493
 494     /* Leave 16 bytes extra to allow for the ALAC header which is about 55 bits */
 495     bufmax = length + header_size + 16;
 496     pa_memchunk_reset(encoded);
 497     encoded->memblock = pa_memblock_new(c->core->mempool, bufmax);
 498     b = pa_memblock_acquire(encoded->memblock);
 499     memcpy(b, header, header_size);
 500
 501     /* Now write the actual samples */
 502     bp = b + header_size;
 503     size = bpos = 0;
 504     bit_writer(&bp,&bpos,&size,1,3); /* channel=1, stereo */
 505     bit_writer(&bp,&bpos,&size,0,4); /* unknown */
 506     bit_writer(&bp,&bpos,&size,0,8); /* unknown */
 507     bit_writer(&bp,&bpos,&size,0,4); /* unknown */
 508     bit_writer(&bp,&bpos,&size,1,1); /* hassize */
 509     bit_writer(&bp,&bpos,&size,0,2); /* unused */
 510     bit_writer(&bp,&bpos,&size,1,1); /* is-not-compressed */
 511
 512     /* size of data, integer, big endian */
 513     bit_writer(&bp,&bpos,&size,(bsize>>24)&0xff,8);
 514     bit_writer(&bp,&bpos,&size,(bsize>>16)&0xff,8);
 515     bit_writer(&bp,&bpos,&size,(bsize>>8)&0xff,8);
 516     bit_writer(&bp,&bpos,&size,(bsize)&0xff,8);
 517
 518     ibp = p = pa_memblock_acquire(raw->memblock);
 519     maxibp = p + raw->length - 4;
 520     while (ibp <= maxibp) {
 521         /* Byte swap stereo data */
 522         bit_writer(&bp,&bpos,&size,*(ibp+1),8);
 523         bit_writer(&bp,&bpos,&size,*(ibp+0),8);
 524         bit_writer(&bp,&bpos,&size,*(ibp+3),8);
 525         bit_writer(&bp,&bpos,&size,*(ibp+2),8);
 526         ibp += 4;
 527         raw->index += 4;
 528         raw->length -= 4;
 529     }
 530     pa_memblock_release(raw->memblock);
 531     encoded->length = header_size + size;
 532
 533     /* store the length (endian swapped: make this better) */
 534     len = size + header_size - 4;
 535     *(b + 2) = len >> 8;
 536     *(b + 3) = len & 0xff;
 537
 538     /* encrypt our data */
 539     aes_encrypt(c, (b + header_size), size);
 540
 541     /* We're done with the chunk */
 542     pa_memblock_release(encoded->memblock);
 543
 544     return 0;
 545 }
 546
 547 void pa_raop_client_set_callback(pa_raop_client* c, pa_raop_client_cb_t callback, void *userdata) {
 548     pa_assert(c);
 549
 550     c->callback = callback;
 551     c->userdata = userdata;
 552 }
 553
 554 void pa_raop_client_set_closed_callback(pa_raop_client* c, pa_raop_client_closed_cb_t callback, void *userdata) {
 555     pa_assert(c);
 556
 557     c->closed_callback = callback;
 558     c->closed_userdata = userdata;
 559 }