Training courses

Kernel and Embedded Linux

Bootlin training courses

Embedded Linux, kernel,
Yocto Project, Buildroot, real-time,
graphics, boot time, debugging...

Bootlin logo

Elixir Cross Referencer

   1
   2
   3
   4
   5
   6
   7
   8
   9
  10
  11
  12
  13
  14
  15
  16
  17
  18
  19
  20
  21
  22
  23
  24
  25
  26
  27
  28
  29
  30
  31
  32
  33
  34
  35
  36
  37
  38
  39
  40
  41
  42
  43
  44
  45
  46
  47
  48
  49
  50
  51
  52
  53
  54
  55
  56
  57
  58
  59
  60
  61
  62
  63
  64
  65
  66
  67
  68
  69
  70
  71
  72
  73
  74
  75
  76
  77
  78
  79
  80
  81
  82
  83
  84
  85
  86
  87
  88
  89
  90
  91
  92
  93
  94
  95
  96
  97
  98
  99
 100
 101
 102
 103
 104
 105
 106
 107
 108
 109
 110
 111
 112
 113
 114
 115
 116
 117
 118
 119
 120
 121
 122
 123
 124
 125
 126
 127
 128
 129
 130
 131
 132
 133
 134
 135
 136
 137
 138
 139
 140
 141
 142
 143
 144
 145
 146
 147
 148
 149
 150
 151
 152
 153
 154
 155
 156
 157
 158
 159
 160
 161
 162
 163
 164
 165
 166
 167
 168
 169
 170
 171
 172
 173
 174
 175
 176
 177
 178
 179
 180
 181
 182
 183
 184
 185
 186
 187
 188
 189
 190
 191
 192
 193
 194
 195
 196
 197
 198
 199
 200
 201
 202
 203
 204
 205
 206
 207
 208
 209
 210
 211
 212
 213
 214
 215
 216
 217
 218
 219
 220
 221
 222
 223
 224
 225
 226
 227
 228
 229
 230
 231
 232
 233
 234
 235
 236
 237
 238
 239
 240
 241
 242
 243
 244
 245
 246
 247
 248
 249
 250
 251
 252
 253
 254
 255
 256
 257
 258
 259
 260
 261
 262
 263
 264
 265
 266
 267
 268
 269
 270
 271
 272
 273
 274
 275
 276
 277
 278
 279
 280
 281
 282
 283
 284
 285
 286
 287
 288
 289
 290
 291
 292
 293
 294
 295
 296
 297
 298
 299
 300
 301
 302
 303
 304
 305
 306
 307
 308
 309
 310
 311
 312
 313
 314
 315
 316
 317
 318
 319
 320
 321
 322
 323
 324
 325
 326
 327
 328
 329
 330
 331
 332
 333
 334
 335
 336
 337
 338
 339
 340
 341
 342
 343
 344
 345
 346
 347
 348
 349
 350
 351
 352
 353
 354
 355
 356
 357
 358
 359
 360
 361
 362
 363
 364
 365
 366
 367
 368
 369
 370
 371
 372
 373
 374
 375
 376
 377
 378
 379
 380
 381
 382
 383
 384
 385
 386
 387
 388
 389
 390
 391
 392
 393
 394
 395
 396
 397
 398
 399
 400
 401
 402
 403
 404
 405
 406
 407
 408
 409
 410
 411
 412
 413
 414
 415
 416
 417
 418
 419
 420
 421
 422
 423
 424
 425
 426
 427
 428
 429
 430
 431
 432
 433
 434
 435
 436
 437
 438
 439
 440
 441
 442
 443
 444
 445
 446
 447
 448
 449
 450
 451
 452
 453
 454
 455
 456
 457
 458
 459
 460
 461
 462
 463
 464
 465
 466
 467
 468
 469
 470
 471
 472
 473
 474
 475
 476
 477
 478
 479
 480
 481
 482
 483
 484
 485
 486
 487
 488
 489
 490
 491
 492
 493
 494
 495
 496
 497
 498
 499
 500
 501
 502
 503
 504
 505
 506
 507
 508
 509
 510
 511
 512
 513
 514
 515
 516
 517
 518
 519
 520
 521
 522
 523
 524
 525
 526
 527
 528
 529
 530
 531
 532
 533
 534
 535
 536
 537
 538
 539
 540
 541
 542
 543
 544
 545
 546
 547
 548
 549
 550
 551
 552
 553
 554
 555
 556
 557
 558
 559
 560
 561
 562
 563
 564
 565
 566
 567
 568
 569
 570
 571
 572
 573
 574
 575
 576
 577
 578
 579
 580
 581
 582
 583
 584
 585
 586
 587
 588
 589
 590
 591
 592
 593
 594
 595
 596
 597
 598
 599
 600
 601
 602
 603
 604
 605
 606
 607
 608
 609
 610
 611
 612
 613
 614
 615
 616
 617
 618
 619
 620
 621
 622
 623
 624
 625
 626
 627
 628
 629
 630
 631
 632
 633
 634
 635
 636
 637
 638
 639
 640
 641
 642
 643
 644
 645
 646
 647
 648
 649
 650
 651
 652
 653
 654
 655
 656
 657
 658
 659
 660
 661
 662
 663
 664
 665
 666
 667
 668
 669
 670
 671
 672
 673
 674
 675
 676
 677
 678
 679
 680
 681
 682
 683
 684
 685
 686
 687
 688
 689
 690
 691
 692
 693
 694
 695
 696
 697
 698
 699
 700
 701
 702
 703
 704
 705
 706
 707
 708
 709
 710
 711
 712
 713
 714
 715
 716
 717
 718
 719
 720
 721
 722
 723
 724
 725
 726
 727
 728
 729
 730
 731
 732
 733
 734
 735
 736
 737
 738
 739
 740
 741
 742
 743
 744
 745
 746
 747
 748
 749
 750
 751
 752
 753
 754
 755
 756
 757
 758
 759
 760
 761
 762
 763
 764
 765
 766
 767
 768
 769
 770
 771
 772
 773
 774
 775
 776
 777
 778
 779
 780
 781
 782
 783
 784
 785
 786
 787
 788
 789
 790
 791
 792
 793
 794
 795
 796
 797
 798
 799
 800
 801
 802
 803
 804
 805
 806
 807
 808
 809
 810
 811
 812
 813
 814
 815
 816
 817
 818
 819
 820
 821
 822
 823
 824
 825
 826
 827
 828
 829
 830
 831
 832
 833
 834
 835
 836
 837
 838
 839
 840
 841
 842
 843
 844
 845
 846
 847
 848
 849
 850
 851
 852
 853
 854
 855
 856
 857
 858
 859
 860
 861
 862
 863
 864
 865
 866
 867
 868
 869
 870
 871
 872
 873
 874
 875
 876
 877
 878
 879
 880
 881
 882
 883
 884
 885
 886
 887
 888
 889
 890
 891
 892
 893
 894
 895
 896
 897
 898
 899
 900
 901
 902
 903
 904
 905
 906
 907
 908
 909
 910
 911
 912
 913
 914
 915
 916
 917
 918
 919
 920
 921
 922
 923
 924
 925
 926
 927
 928
 929
 930
 931
 932
 933
 934
 935
 936
 937
 938
 939
 940
 941
 942
 943
 944
 945
 946
 947
 948
 949
 950
 951
 952
 953
 954
 955
 956
 957
 958
 959
 960
 961
 962
 963
 964
 965
 966
 967
 968
 969
 970
 971
 972
 973
 974
 975
 976
 977
 978
 979
 980
 981
 982
 983
 984
 985
 986
 987
 988
 989
 990
 991
 992
 993
 994
 995
 996
 997
 998
 999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
/*
 * UPnP WPS Device
 * Copyright (c) 2000-2003 Intel Corporation
 * Copyright (c) 2006-2007 Sony Corporation
 * Copyright (c) 2008-2009 Atheros Communications
 * Copyright (c) 2009-2010, Jouni Malinen <j@w1.fi>
 *
 * See below for more details on licensing and code history.
 */

/*
 * This has been greatly stripped down from the original file
 * (upnp_wps_device.c) by Ted Merrill, Atheros Communications
 * in order to eliminate use of the bulky libupnp library etc.
 *
 * History:
 * upnp_wps_device.c is/was a shim layer between wps_opt_upnp.c and
 * the libupnp library.
 * The layering (by Sony) was well done; only a very minor modification
 * to API of upnp_wps_device.c was required.
 * libupnp was found to be undesirable because:
 * -- It consumed too much code and data space
 * -- It uses multiple threads, making debugging more difficult
 *      and possibly reducing reliability.
 * -- It uses static variables and only supports one instance.
 * The shim and libupnp are here replaced by special code written
 * specifically for the needs of hostapd.
 * Various shortcuts can and are taken to keep the code size small.
 * Generally, execution time is not as crucial.
 *
 * BUGS:
 * -- UPnP requires that we be able to resolve domain names.
 * While uncommon, if we have to do it then it will stall the entire
 * hostapd program, which is bad.
 * This is because we use the standard linux getaddrinfo() function
 * which is syncronous.
 * An asyncronous solution would be to use the free "ares" library.
 * -- Does not have a robust output buffering scheme.  Uses a single
 * fixed size output buffer per TCP/HTTP connection, with possible (although
 * unlikely) possibility of overflow and likely excessive use of RAM.
 * A better solution would be to write the HTTP output as a buffered stream,
 * using chunking: (handle header specially, then) generate data with
 * a printf-like function into a buffer, catching buffer full condition,
 * then send it out surrounded by http chunking.
 * -- There is some code that could be separated out into the common
 * library to be shared with wpa_supplicant.
 * -- Needs renaming with module prefix to avoid polluting the debugger
 * namespace and causing possible collisions with other static fncs
 * and structure declarations when using the debugger.
 * -- The http error code generation is pretty bogus, hopefully no one cares.
 *
 * Author: Ted Merrill, Atheros Communications, based upon earlier work
 * as explained above and below.
 *
 * Copyright:
 * Copyright 2008 Atheros Communications.
 *
 * The original header (of upnp_wps_device.c) reads:
 *
 *  Copyright (c) 2006-2007 Sony Corporation. All Rights Reserved.
 *
 *  File Name: upnp_wps_device.c
 *  Description: EAP-WPS UPnP device source
 *
 *   Redistribution and use in source and binary forms, with or without
 *   modification, are permitted provided that the following conditions
 *   are met:
 *
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in
 *       the documentation and/or other materials provided with the
 *       distribution.
 *     * Neither the name of Sony Corporation nor the names of its
 *       contributors may be used to endorse or promote products derived
 *       from this software without specific prior written permission.
 *
 *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * Portions from Intel libupnp files, e.g. genlib/net/http/httpreadwrite.c
 * typical header:
 *
 * Copyright (c) 2000-2003 Intel Corporation
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * * Redistributions of source code must retain the above copyright notice,
 * this list of conditions and the following disclaimer.
 * * Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 * * Neither name of Intel Corporation nor the names of its contributors
 * may be used to endorse or promote products derived from this software
 * without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL INTEL OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/

/*
 * Overview of WPS over UPnP:
 *
 * UPnP is a protocol that allows devices to discover each other and control
 * each other. In UPnP terminology, a device is either a "device" (a server
 * that provides information about itself and allows itself to be controlled)
 * or a "control point" (a client that controls "devices") or possibly both.
 * This file implements a UPnP "device".
 *
 * For us, we use mostly basic UPnP discovery, but the control part of interest
 * is WPS carried via UPnP messages. There is quite a bit of basic UPnP
 * discovery to do before we can get to WPS, however.
 *
 * UPnP discovery begins with "devices" send out multicast UDP packets to a
 * certain fixed multicast IP address and port, and "control points" sending
 * out other such UDP packets.
 *
 * The packets sent by devices are NOTIFY packets (not to be confused with TCP
 * NOTIFY packets that are used later) and those sent by control points are
 * M-SEARCH packets. These packets contain a simple HTTP style header. The
 * packets are sent redundantly to get around packet loss. Devices respond to
 * M-SEARCH packets with HTTP-like UDP packets containing HTTP/1.1 200 OK
 * messages, which give similar information as the UDP NOTIFY packets.
 *
 * The above UDP packets advertise the (arbitrary) TCP ports that the
 * respective parties will listen to. The control point can then do a HTTP
 * SUBSCRIBE (something like an HTTP PUT) after which the device can do a
 * separate HTTP NOTIFY (also like an HTTP PUT) to do event messaging.
 *
 * The control point will also do HTTP GET of the "device file" listed in the
 * original UDP information from the device (see UPNP_WPS_DEVICE_XML_FILE
 * data), and based on this will do additional GETs... HTTP POSTs are done to
 * cause an action.
 *
 * Beyond some basic information in HTTP headers, additional information is in
 * the HTTP bodies, in a format set by the SOAP and XML standards, a markup
 * language related to HTML used for web pages. This language is intended to
 * provide the ultimate in self-documentation by providing a universal
 * namespace based on pseudo-URLs called URIs. Note that although a URI looks
 * like a URL (a web address), they are never accessed as such but are used
 * only as identifiers.
 *
 * The POST of a GetDeviceInfo gets information similar to what might be
 * obtained from a probe request or response on Wi-Fi. WPS messages M1-M8
 * are passed via a POST of a PutMessage; the M1-M8 WPS messages are converted
 * to a bin64 ascii representation for encapsulation. When proxying messages,
 * WLANEvent and PutWLANResponse are used.
 *
 * This of course glosses over a lot of details.
 */

#include "includes.h"

#include <time.h>
#include <net/if.h>
#include <netdb.h>
#include <sys/ioctl.h>

#include "common.h"
#include "uuid.h"
#include "base64.h"
#include "wps.h"
#include "wps_i.h"
#include "wps_upnp.h"
#include "wps_upnp_i.h"


/*
 * UPnP allows a client ("control point") to send a server like us ("device")
 * a domain name for registration, and we are supposed to resolve it. This is
 * bad because, using the standard Linux library, we will stall the entire
 * hostapd waiting for resolution.
 *
 * The "correct" solution would be to use an event driven library for domain
 * name resolution such as "ares". However, this would increase code size
 * further. Since it is unlikely that we'll actually see such domain names, we
 * can just refuse to accept them.
 */
#define NO_DOMAIN_NAME_RESOLUTION 1  /* 1 to allow only dotted ip addresses */


/*
 * UPnP does not scale well. If we were in a room with thousands of control
 * points then potentially we could be expected to handle subscriptions for
 * each of them, which would exhaust our memory. So we must set a limit. In
 * practice we are unlikely to see more than one or two.
 */
#define MAX_SUBSCRIPTIONS 4    /* how many subscribing clients we handle */
#define MAX_ADDR_PER_SUBSCRIPTION 8

/* Maximum number of Probe Request events per second */
#define MAX_EVENTS_PER_SEC 5


static struct upnp_wps_device_sm *shared_upnp_device = NULL;


/* Write the current date/time per RFC */
void format_date(struct wpabuf *buf)
{
	const char *weekday_str = "Sun\0Mon\0Tue\0Wed\0Thu\0Fri\0Sat";
	const char *month_str = "Jan\0Feb\0Mar\0Apr\0May\0Jun\0"
		"Jul\0Aug\0Sep\0Oct\0Nov\0Dec";
	struct tm *date;
	time_t t;

	t = time(NULL);
	date = gmtime(&t);
	if (date == NULL)
		return;
	wpabuf_printf(buf, "%s, %02d %s %d %02d:%02d:%02d GMT",
		      &weekday_str[date->tm_wday * 4], date->tm_mday,
		      &month_str[date->tm_mon * 4], date->tm_year + 1900,
		      date->tm_hour, date->tm_min, date->tm_sec);
}


/***************************************************************************
 * UUIDs (unique identifiers)
 *
 * These are supposed to be unique in all the world.
 * Sometimes permanent ones are used, sometimes temporary ones
 * based on random numbers... there are different rules for valid content
 * of different types.
 * Each uuid is 16 bytes long.
 **************************************************************************/

/* uuid_make -- construct a random UUID
 * The UPnP documents don't seem to offer any guidelines as to which method to
 * use for constructing UUIDs for subscriptions. Presumably any method from
 * rfc4122 is good enough; I've chosen random number method.
 */
static int uuid_make(u8 uuid[UUID_LEN])
{
	if (os_get_random(uuid, UUID_LEN) < 0)
		return -1;

	/* Replace certain bits as specified in rfc4122 or X.667 */
	uuid[6] &= 0x0f; uuid[6] |= (4 << 4);   /* version 4 == random gen */
	uuid[8] &= 0x3f; uuid[8] |= 0x80;

	return 0;
}


/*
 * Subscriber address handling.
 * Since a subscriber may have an arbitrary number of addresses, we have to
 * add a bunch of code to handle them.
 *
 * Addresses are passed in text, and MAY be domain names instead of the (usual
 * and expected) dotted IP addresses. Resolving domain names consumes a lot of
 * resources. Worse, we are currently using the standard Linux getaddrinfo()
 * which will block the entire program until complete or timeout! The proper
 * solution would be to use the "ares" library or similar with more state
 * machine steps etc. or just disable domain name resolution by setting
 * NO_DOMAIN_NAME_RESOLUTION to 1 at top of this file.
 */

/* subscr_addr_delete -- delete single unlinked subscriber address
 * (be sure to unlink first if need be)
 */
void subscr_addr_delete(struct subscr_addr *a)
{
	/*
	 * Note: do NOT free domain_and_port or path because they point to
	 * memory within the allocation of "a".
	 */
	os_free(a);
}


/* subscr_addr_free_all -- unlink and delete list of subscriber addresses. */
static void subscr_addr_free_all(struct subscription *s)
{
	struct subscr_addr *a, *tmp;
	dl_list_for_each_safe(a, tmp, &s->addr_list, struct subscr_addr, list)
	{
		dl_list_del(&a->list);
		subscr_addr_delete(a);
	}
}


/* subscr_addr_add_url -- add address(es) for one url to subscription */
static void subscr_addr_add_url(struct subscription *s, const char *url,
				size_t url_len)
{
	int alloc_len;
	char *scratch_mem = NULL;
	char *mem;
	char *host;
	char *delim;
	char *path;
	int port = 80;  /* port to send to (default is port 80) */
	struct addrinfo hints;
	struct addrinfo *result = NULL;
	struct addrinfo *rp;
	int rerr;
	size_t host_len, path_len;

	/* url MUST begin with http: */
	if (url_len < 7 || os_strncasecmp(url, "http://", 7))
		goto fail;
	url += 7;
	url_len -= 7;

	/* Make a copy of the string to allow modification during parsing */
	scratch_mem = dup_binstr(url, url_len);
	if (scratch_mem == NULL)
		goto fail;
	wpa_printf(MSG_DEBUG, "WPS UPnP: Adding URL '%s'", scratch_mem);
	host = scratch_mem;
	path = os_strchr(host, '/');
	if (path)
		*path++ = '\0'; /* null terminate host */

	/* Process and remove optional port component */
	delim = os_strchr(host, ':');
	if (delim) {
		*delim = '\0'; /* null terminate host name for now */
		if (isdigit(delim[1]))
			port = atol(delim + 1);
	}

	/*
	 * getaddrinfo does the right thing with dotted decimal notations, or
	 * will resolve domain names. Resolving domain names will unfortunately
	 * hang the entire program until it is resolved or it times out
	 * internal to getaddrinfo; fortunately we think that the use of actual
	 * domain names (vs. dotted decimal notations) should be uncommon.
	 */
	os_memset(&hints, 0, sizeof(struct addrinfo));
	hints.ai_family = AF_INET;      /* IPv4 */
	hints.ai_socktype = SOCK_STREAM;
#if NO_DOMAIN_NAME_RESOLUTION
	/* Suppress domain name resolutions that would halt
	 * the program for periods of time
	 */
	hints.ai_flags = AI_NUMERICHOST;
#else
	/* Allow domain name resolution. */
	hints.ai_flags = 0;
#endif
	hints.ai_protocol = 0;          /* Any protocol? */
	rerr = getaddrinfo(host, NULL /* fill in port ourselves */,
			   &hints, &result);
	if (rerr) {
		wpa_printf(MSG_INFO, "WPS UPnP: Resolve error %d (%s) on: %s",
			   rerr, gai_strerror(rerr), host);
		goto fail;
	}

	if (delim)
		*delim = ':'; /* Restore port */

	host_len = os_strlen(host);
	path_len = path ? os_strlen(path) : 0;
	alloc_len = host_len + 1 + 1 + path_len + 1;

	for (rp = result; rp; rp = rp->ai_next) {
		struct subscr_addr *a;

		/* Limit no. of address to avoid denial of service attack */
		if (dl_list_len(&s->addr_list) >= MAX_ADDR_PER_SUBSCRIPTION) {
			wpa_printf(MSG_INFO, "WPS UPnP: subscr_addr_add_url: "
				   "Ignoring excessive addresses");
			break;
		}

		a = os_zalloc(sizeof(*a) + alloc_len);
		if (a == NULL)
			break;
		mem = (char *) (a + 1);
		a->domain_and_port = mem;
		os_memcpy(mem, host, host_len);
		mem += host_len + 1;
		a->path = mem;
		if (path == NULL || path[0] != '/')
			*mem++ = '/';
		if (path)
			os_memcpy(mem, path, path_len);
		os_memcpy(&a->saddr, rp->ai_addr, sizeof(a->saddr));
		a->saddr.sin_port = htons(port);

		dl_list_add(&s->addr_list, &a->list);
	}

fail:
	if (result)
		freeaddrinfo(result);
	os_free(scratch_mem);
}


/* subscr_addr_list_create -- create list from urls in string.
 *      Each url is enclosed by angle brackets.
 */
static void subscr_addr_list_create(struct subscription *s,
				    const char *url_list)
{
	const char *end;
	wpa_printf(MSG_DEBUG, "WPS UPnP: Parsing URL list '%s'", url_list);
	for (;;) {
		while (*url_list == ' ' || *url_list == '\t')
			url_list++;
		if (*url_list != '<')
			break;
		url_list++;
		end = os_strchr(url_list, '>');
		if (end == NULL)
			break;
		subscr_addr_add_url(s, url_list, end - url_list);
		url_list = end + 1;
	}
}


static void wpabuf_put_property(struct wpabuf *buf, const char *name,
				const char *value)
{
	wpabuf_put_str(buf, "<e:property>");
	wpabuf_printf(buf, "<%s>", name);
	if (value)
		wpabuf_put_str(buf, value);
	wpabuf_printf(buf, "</%s>", name);
	wpabuf_put_str(buf, "</e:property>\n");
}


/**
 * upnp_wps_device_send_event - Queue event messages for subscribers
 * @sm: WPS UPnP state machine from upnp_wps_device_init()
 *
 * This function queues the last WLANEvent to be sent for all currently
 * subscribed UPnP control points. sm->wlanevent must have been set with the
 * encoded data before calling this function.
 */
static void upnp_wps_device_send_event(struct upnp_wps_device_sm *sm)
{
	/* Enqueue event message for all subscribers */
	struct wpabuf *buf; /* holds event message */
	int buf_size = 0;
	struct subscription *s, *tmp;
	/* Actually, utf-8 is the default, but it doesn't hurt to specify it */
	const char *format_head =
		"<?xml version=\"1.0\" encoding=\"utf-8\"?>\n"
		"<e:propertyset xmlns:e=\"urn:schemas-upnp-org:event-1-0\">\n";
	const char *format_tail = "</e:propertyset>\n";
	struct os_reltime now;

	if (dl_list_empty(&sm->subscriptions)) {
		/* optimize */
		return;
	}

	if (os_get_reltime(&now) == 0) {
		if (now.sec != sm->last_event_sec) {
			sm->last_event_sec = now.sec;
			sm->num_events_in_sec = 1;
		} else {
			sm->num_events_in_sec++;
			/*
			 * In theory, this should apply to all WLANEvent
			 * notifications, but EAP messages are of much higher
			 * priority and Probe Request notifications should not
			 * be allowed to drop EAP messages, so only throttle
			 * Probe Request notifications.
			 */
			if (sm->num_events_in_sec > MAX_EVENTS_PER_SEC &&
			    sm->wlanevent_type ==
			    UPNP_WPS_WLANEVENT_TYPE_PROBE) {
				wpa_printf(MSG_DEBUG, "WPS UPnP: Throttle "
					   "event notifications (%u seen "
					   "during one second)",
					   sm->num_events_in_sec);
				return;
			}
		}
	}

	/* Determine buffer size needed first */
	buf_size += os_strlen(format_head);
	buf_size += 50 + 2 * os_strlen("WLANEvent");
	if (sm->wlanevent)
		buf_size += os_strlen(sm->wlanevent);
	buf_size += os_strlen(format_tail);

	buf = wpabuf_alloc(buf_size);
	if (buf == NULL)
		return;
	wpabuf_put_str(buf, format_head);
	wpabuf_put_property(buf, "WLANEvent", sm->wlanevent);
	wpabuf_put_str(buf, format_tail);

	wpa_printf(MSG_MSGDUMP, "WPS UPnP: WLANEvent message:\n%s",
		   (char *) wpabuf_head(buf));

	dl_list_for_each_safe(s, tmp, &sm->subscriptions, struct subscription,
			      list) {
		event_add(s, buf,
			  sm->wlanevent_type == UPNP_WPS_WLANEVENT_TYPE_PROBE);
	}

	wpabuf_free(buf);
}


/*
 * Event subscription (subscriber machines register with us to receive event
 * messages).
 * This is the result of an incoming HTTP over TCP SUBSCRIBE request.
 */

/* subscription_destroy -- destroy an unlinked subscription
 * Be sure to unlink first if necessary.
 */
void subscription_destroy(struct subscription *s)
{
	struct upnp_wps_device_interface *iface;
	wpa_printf(MSG_DEBUG, "WPS UPnP: Destroy subscription %p", s);
	subscr_addr_free_all(s);
	event_delete_all(s);
	dl_list_for_each(iface, &s->sm->interfaces,
			 struct upnp_wps_device_interface, list)
		upnp_er_remove_notification(iface->wps->registrar, s);
	os_free(s);
}


/* subscription_list_age -- remove expired subscriptions */
static void subscription_list_age(struct upnp_wps_device_sm *sm, time_t now)
{
	struct subscription *s, *tmp;
	dl_list_for_each_safe(s, tmp, &sm->subscriptions,
			      struct subscription, list) {
		if (s->timeout_time > now)
			break;
		wpa_printf(MSG_DEBUG, "WPS UPnP: Removing aged subscription");
		dl_list_del(&s->list);
		subscription_destroy(s);
	}
}


/* subscription_find -- return existing subscription matching uuid, if any
 * returns NULL if not found
 */
struct subscription * subscription_find(struct upnp_wps_device_sm *sm,
					const u8 uuid[UUID_LEN])
{
	struct subscription *s;
	dl_list_for_each(s, &sm->subscriptions, struct subscription, list) {
		if (os_memcmp(s->uuid, uuid, UUID_LEN) == 0)
			return s; /* Found match */
	}
	return NULL;
}


static struct wpabuf * build_fake_wsc_ack(void)
{
	struct wpabuf *msg = wpabuf_alloc(100);
	if (msg == NULL)
		return NULL;
	wpabuf_put_u8(msg, UPNP_WPS_WLANEVENT_TYPE_EAP);
	wpabuf_put_str(msg, "00:00:00:00:00:00");
	if (wps_build_version(msg) ||
	    wps_build_msg_type(msg, WPS_WSC_ACK)) {
		wpabuf_free(msg);
		return NULL;
	}
	/* Enrollee Nonce */
	wpabuf_put_be16(msg, ATTR_ENROLLEE_NONCE);
	wpabuf_put_be16(msg, WPS_NONCE_LEN);
	wpabuf_put(msg, WPS_NONCE_LEN);
	/* Registrar Nonce */
	wpabuf_put_be16(msg, ATTR_REGISTRAR_NONCE);
	wpabuf_put_be16(msg, WPS_NONCE_LEN);
	wpabuf_put(msg, WPS_NONCE_LEN);
	if (wps_build_wfa_ext(msg, 0, NULL, 0, 0)) {
		wpabuf_free(msg);
		return NULL;
	}
	return msg;
}


/* subscription_first_event -- send format/queue event that is automatically
 * sent on a new subscription.
 */
static int subscription_first_event(struct subscription *s)
{
	/*
	 * Actually, utf-8 is the default, but it doesn't hurt to specify it.
	 *
	 * APStatus is apparently a bit set,
	 * 0x1 = configuration change (but is always set?)
	 * 0x10 = ap is locked
	 *
	 * Per UPnP spec, we send out the last value of each variable, even
	 * for WLANEvent, whatever it was.
	 */
	char *wlan_event;
	struct wpabuf *buf;
	int ap_status = 1;      /* TODO: add 0x10 if access point is locked */
	const char *head =
		"<?xml version=\"1.0\" encoding=\"utf-8\"?>\n"
		"<e:propertyset xmlns:e=\"urn:schemas-upnp-org:event-1-0\">\n";
	const char *tail = "</e:propertyset>\n";
	char txt[10];
	int ret;

	if (s->sm->wlanevent == NULL) {
		/*
		 * There has been no events before the subscription. However,
		 * UPnP device architecture specification requires all the
		 * evented variables to be included, so generate a dummy event
		 * for this particular case using a WSC_ACK and all-zeros
		 * nonces. The ER (UPnP control point) will ignore this, but at
		 * least it will learn that WLANEvent variable will be used in
		 * event notifications in the future.
		 */
		struct wpabuf *msg;
		wpa_printf(MSG_DEBUG, "WPS UPnP: Use a fake WSC_ACK as the "
			   "initial WLANEvent");
		msg = build_fake_wsc_ack();
		if (msg) {
			s->sm->wlanevent = (char *)
				base64_encode(wpabuf_head(msg),
					      wpabuf_len(msg), NULL);
			wpabuf_free(msg);
		}
	}

	wlan_event = s->sm->wlanevent;
	if (wlan_event == NULL || *wlan_event == '\0') {
		wpa_printf(MSG_DEBUG, "WPS UPnP: WLANEvent not known for "
			   "initial event message");
		wlan_event = "";
	}
	buf = wpabuf_alloc(500 + os_strlen(wlan_event));
	if (buf == NULL)
		return -1;

	wpabuf_put_str(buf, head);
	wpabuf_put_property(buf, "STAStatus", "1");
	os_snprintf(txt, sizeof(txt), "%d", ap_status);
	wpabuf_put_property(buf, "APStatus", txt);
	if (*wlan_event)
		wpabuf_put_property(buf, "WLANEvent", wlan_event);
	wpabuf_put_str(buf, tail);

	ret = event_add(s, buf, 0);
	if (ret) {
		wpabuf_free(buf);
		return ret;
	}
	wpabuf_free(buf);

	return 0;
}


/**
 * subscription_start - Remember a UPnP control point to send events to.
 * @sm: WPS UPnP state machine from upnp_wps_device_init()
 * @callback_urls: Callback URLs
 * Returns: %NULL on error, or pointer to new subscription structure.
 */
struct subscription * subscription_start(struct upnp_wps_device_sm *sm,
					 const char *callback_urls)
{
	struct subscription *s;
	time_t now = time(NULL);
	time_t expire = now + UPNP_SUBSCRIBE_SEC;
	char str[80];

	/* Get rid of expired subscriptions so we have room */
	subscription_list_age(sm, now);

	/* If too many subscriptions, remove oldest */
	if (dl_list_len(&sm->subscriptions) >= MAX_SUBSCRIPTIONS) {
		s = dl_list_first(&sm->subscriptions, struct subscription,
				  list);
		if (s) {
			wpa_printf(MSG_INFO,
				   "WPS UPnP: Too many subscriptions, trashing oldest");
			dl_list_del(&s->list);
			subscription_destroy(s);
		}
	}

	s = os_zalloc(sizeof(*s));
	if (s == NULL)
		return NULL;
	dl_list_init(&s->addr_list);
	dl_list_init(&s->event_queue);

	s->sm = sm;
	s->timeout_time = expire;
	if (uuid_make(s->uuid) < 0) {
		subscription_destroy(s);
		return NULL;
	}
	subscr_addr_list_create(s, callback_urls);
	if (dl_list_empty(&s->addr_list)) {
		wpa_printf(MSG_DEBUG, "WPS UPnP: No valid callback URLs in "
			   "'%s' - drop subscription", callback_urls);
		subscription_destroy(s);
		return NULL;
	}

	/* Add to end of list, since it has the highest expiration time */
	dl_list_add_tail(&sm->subscriptions, &s->list);
	/* Queue up immediate event message (our last event)
	 * as required by UPnP spec.
	 */
	if (subscription_first_event(s)) {
		wpa_printf(MSG_INFO, "WPS UPnP: Dropping subscriber due to "
			   "event backlog");
		dl_list_del(&s->list);
		subscription_destroy(s);
		return NULL;
	}
	uuid_bin2str(s->uuid, str, sizeof(str));
	wpa_printf(MSG_DEBUG,
		   "WPS UPnP: Subscription %p (SID %s) started with %s",
		   s, str, callback_urls);
	/* Schedule sending this */
	event_send_all_later(sm);
	return s;
}


/* subscription_renew -- find subscription and reset timeout */
struct subscription * subscription_renew(struct upnp_wps_device_sm *sm,
					 const u8 uuid[UUID_LEN])
{
	time_t now = time(NULL);
	time_t expire = now + UPNP_SUBSCRIBE_SEC;
	struct subscription *s = subscription_find(sm, uuid);
	if (s == NULL)
		return NULL;
	wpa_printf(MSG_DEBUG, "WPS UPnP: Subscription renewed");
	dl_list_del(&s->list);
	s->timeout_time = expire;
	/* add back to end of list, since it now has highest expiry */
	dl_list_add_tail(&sm->subscriptions, &s->list);
	return s;
}


/**
 * upnp_wps_device_send_wlan_event - Event notification
 * @sm: WPS UPnP state machine from upnp_wps_device_init()
 * @from_mac_addr: Source (Enrollee) MAC address for the event
 * @ev_type: Event type
 * @msg: Event data
 * Returns: 0 on success, -1 on failure
 *
 * Tell external Registrars (UPnP control points) that something happened. In
 * particular, events include WPS messages from clients that are proxied to
 * external Registrars.
 */
int upnp_wps_device_send_wlan_event(struct upnp_wps_device_sm *sm,
				    const u8 from_mac_addr[ETH_ALEN],
				    enum upnp_wps_wlanevent_type ev_type,
				    const struct wpabuf *msg)
{
	int ret = -1;
	char type[2];
	const u8 *mac = from_mac_addr;
	char mac_text[18];
	u8 *raw = NULL;
	size_t raw_len;
	char *val;
	size_t val_len;
	int pos = 0;

	if (!sm)
		goto fail;

	os_snprintf(type, sizeof(type), "%1u", ev_type);

	raw_len = 1 + 17 + (msg ? wpabuf_len(msg) : 0);
	raw = os_zalloc(raw_len);
	if (!raw)
		goto fail;

	*(raw + pos) = (u8) ev_type;
	pos += 1;
	os_snprintf(mac_text, sizeof(mac_text), MACSTR, MAC2STR(mac));
	wpa_printf(MSG_DEBUG, "WPS UPnP: Proxying WLANEvent from %s",
		   mac_text);
	os_memcpy(raw + pos, mac_text, 17);
	pos += 17;
	if (msg) {
		os_memcpy(raw + pos, wpabuf_head(msg), wpabuf_len(msg));
		pos += wpabuf_len(msg);
	}
	raw_len = pos;

	val = (char *) base64_encode(raw, raw_len, &val_len);
	if (val == NULL)
		goto fail;

	os_free(sm->wlanevent);
	sm->wlanevent = val;
	sm->wlanevent_type = ev_type;
	upnp_wps_device_send_event(sm);

	ret = 0;

fail:
	os_free(raw);

	return ret;
}


#if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
#include <sys/sysctl.h>
#include <net/route.h>
#include <net/if_dl.h>

static int eth_get(const char *device, u8 ea[ETH_ALEN])
{
	struct if_msghdr *ifm;
	struct sockaddr_dl *sdl;
	u_char *p, *buf;
	size_t len;
	int mib[] = { CTL_NET, AF_ROUTE, 0, AF_LINK, NET_RT_IFLIST, 0 };

	if (sysctl(mib, 6, NULL, &len, NULL, 0) < 0)
		return -1;
	if ((buf = os_malloc(len)) == NULL)
		return -1;
	if (sysctl(mib, 6, buf, &len, NULL, 0) < 0) {
		os_free(buf);
		return -1;
	}
	for (p = buf; p < buf + len; p += ifm->ifm_msglen) {
		ifm = (struct if_msghdr *)p;
		sdl = (struct sockaddr_dl *)(ifm + 1);
		if (ifm->ifm_type != RTM_IFINFO ||
		    (ifm->ifm_addrs & RTA_IFP) == 0)
			continue;
		if (sdl->sdl_family != AF_LINK || sdl->sdl_nlen == 0 ||
		    os_memcmp(sdl->sdl_data, device, sdl->sdl_nlen) != 0)
			continue;
		os_memcpy(ea, LLADDR(sdl), sdl->sdl_alen);
		break;
	}
	os_free(buf);

	if (p >= buf + len) {
		errno = ESRCH;
		return -1;
	}
	return 0;
}
#endif /* __FreeBSD__ */


/**
 * get_netif_info - Get hw and IP addresses for network device
 * @net_if: Selected network interface name
 * @ip_addr: Buffer for returning IP address in network byte order
 * @ip_addr_text: Buffer for returning a pointer to allocated IP address text
 * @mac: Buffer for returning MAC address
 * Returns: 0 on success, -1 on failure
 */
int get_netif_info(const char *net_if, unsigned *ip_addr, char **ip_addr_text,
		   u8 mac[ETH_ALEN])
{
	struct ifreq req;
	int sock = -1;
	struct sockaddr_in *addr;
	struct in_addr in_addr;

	*ip_addr_text = os_zalloc(16);
	if (*ip_addr_text == NULL)
		goto fail;

	sock = socket(AF_INET, SOCK_DGRAM, 0);
	if (sock < 0)
		goto fail;

	os_strlcpy(req.ifr_name, net_if, sizeof(req.ifr_name));
	if (ioctl(sock, SIOCGIFADDR, &req) < 0) {
		wpa_printf(MSG_ERROR, "WPS UPnP: SIOCGIFADDR failed: %d (%s)",
			   errno, strerror(errno));
		goto fail;
	}
	addr = (void *) &req.ifr_addr;
	*ip_addr = addr->sin_addr.s_addr;
	in_addr.s_addr = *ip_addr;
	os_snprintf(*ip_addr_text, 16, "%s", inet_ntoa(in_addr));

#ifdef __linux__
	os_strlcpy(req.ifr_name, net_if, sizeof(req.ifr_name));
	if (ioctl(sock, SIOCGIFHWADDR, &req) < 0) {
		wpa_printf(MSG_ERROR, "WPS UPnP: SIOCGIFHWADDR failed: "
			   "%d (%s)", errno, strerror(errno));
		goto fail;
	}
	os_memcpy(mac, req.ifr_addr.sa_data, 6);
#elif defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
	if (eth_get(net_if, mac) < 0) {
		wpa_printf(MSG_ERROR, "WPS UPnP: Failed to get MAC address");
		goto fail;
	}
#else
#error MAC address fetch not implemented
#endif

	close(sock);
	return 0;

fail:
	if (sock >= 0)
		close(sock);
	os_free(*ip_addr_text);
	*ip_addr_text = NULL;
	return -1;
}


static void upnp_wps_free_msearchreply(struct dl_list *head)
{
	struct advertisement_state_machine *a, *tmp;
	dl_list_for_each_safe(a, tmp, head, struct advertisement_state_machine,
			      list)
		msearchreply_state_machine_stop(a);
}


static void upnp_wps_free_subscriptions(struct dl_list *head,
					struct wps_registrar *reg)
{
	struct subscription *s, *tmp;
	dl_list_for_each_safe(s, tmp, head, struct subscription, list) {
		if (reg && s->reg != reg)
			continue;
		dl_list_del(&s->list);
		subscription_destroy(s);
	}
}


/**
 * upnp_wps_device_stop - Stop WPS UPnP operations on an interface
 * @sm: WPS UPnP state machine from upnp_wps_device_init()
 */
static void upnp_wps_device_stop(struct upnp_wps_device_sm *sm)
{
	if (!sm || !sm->started)
		return;

	wpa_printf(MSG_DEBUG, "WPS UPnP: Stop device");
	web_listener_stop(sm);
	ssdp_listener_stop(sm);
	upnp_wps_free_msearchreply(&sm->msearch_replies);
	upnp_wps_free_subscriptions(&sm->subscriptions, NULL);

	advertisement_state_machine_stop(sm, 1);

	event_send_stop_all(sm);
	os_free(sm->wlanevent);
	sm->wlanevent = NULL;
	os_free(sm->ip_addr_text);
	sm->ip_addr_text = NULL;
	if (sm->multicast_sd >= 0)
		close(sm->multicast_sd);
	sm->multicast_sd = -1;

	sm->started = 0;
}


/**
 * upnp_wps_device_start - Start WPS UPnP operations on an interface
 * @sm: WPS UPnP state machine from upnp_wps_device_init()
 * @net_if: Selected network interface name
 * Returns: 0 on success, -1 on failure
 */
static int upnp_wps_device_start(struct upnp_wps_device_sm *sm, char *net_if)
{
	if (!sm || !net_if)
		return -1;

	if (sm->started)
		upnp_wps_device_stop(sm);

	sm->multicast_sd = -1;
	sm->ssdp_sd = -1;
	sm->started = 1;
	sm->advertise_count = 0;

	/* Fix up linux multicast handling */
	if (add_ssdp_network(net_if))
		goto fail;

	/* Determine which IP and mac address we're using */
	if (get_netif_info(net_if, &sm->ip_addr, &sm->ip_addr_text,
			   sm->mac_addr)) {
		wpa_printf(MSG_INFO, "WPS UPnP: Could not get IP/MAC address "
			   "for %s. Does it have IP address?", net_if);
		goto fail;
	}

	/* Listen for incoming TCP connections so that others
	 * can fetch our "xml files" from us.
	 */
	if (web_listener_start(sm))
		goto fail;

	/* Set up for receiving discovery (UDP) packets */
	if (ssdp_listener_start(sm))
		goto fail;

	/* Set up for sending multicast */
	if (ssdp_open_multicast(sm) < 0)
		goto fail;

	/*
	 * Broadcast NOTIFY messages to let the world know we exist.
	 * This is done via a state machine since the messages should not be
	 * all sent out at once.
	 */
	if (advertisement_state_machine_start(sm))
		goto fail;

	return 0;

fail:
	upnp_wps_device_stop(sm);
	return -1;
}


static struct upnp_wps_device_interface *
upnp_wps_get_iface(struct upnp_wps_device_sm *sm, void *priv)
{
	struct upnp_wps_device_interface *iface;
	dl_list_for_each(iface, &sm->interfaces,
			 struct upnp_wps_device_interface, list) {
		if (iface->priv == priv)
			return iface;
	}
	return NULL;
}


/**
 * upnp_wps_device_deinit - Deinitialize WPS UPnP
 * @sm: WPS UPnP state machine from upnp_wps_device_init()
 * @priv: External context data that was used in upnp_wps_device_init() call
 */
void upnp_wps_device_deinit(struct upnp_wps_device_sm *sm, void *priv)
{
	struct upnp_wps_device_interface *iface;
	struct upnp_wps_peer *peer;

	if (!sm)
		return;

	iface = upnp_wps_get_iface(sm, priv);
	if (iface == NULL) {
		wpa_printf(MSG_ERROR, "WPS UPnP: Could not find the interface "
			   "instance to deinit");
		return;
	}
	wpa_printf(MSG_DEBUG, "WPS UPnP: Deinit interface instance %p", iface);
	if (dl_list_len(&sm->interfaces) == 1) {
		wpa_printf(MSG_DEBUG, "WPS UPnP: Deinitializing last instance "
			   "- free global device instance");
		upnp_wps_device_stop(sm);
	} else
		upnp_wps_free_subscriptions(&sm->subscriptions,
					    iface->wps->registrar);
	dl_list_del(&iface->list);

	while ((peer = dl_list_first(&iface->peers, struct upnp_wps_peer,
				     list))) {
		if (peer->wps)
			wps_deinit(peer->wps);
		dl_list_del(&peer->list);
		os_free(peer);
	}
	os_free(iface->ctx->ap_pin);
	os_free(iface->ctx);
	os_free(iface);

	if (dl_list_empty(&sm->interfaces)) {
		os_free(sm->root_dir);
		os_free(sm->desc_url);
		os_free(sm);
		shared_upnp_device = NULL;
	}
}


/**
 * upnp_wps_device_init - Initialize WPS UPnP
 * @ctx: callback table; we must eventually free it
 * @wps: Pointer to longterm WPS context
 * @priv: External context data that will be used in callbacks
 * @net_if: Selected network interface name
 * Returns: WPS UPnP state or %NULL on failure
 */
struct upnp_wps_device_sm *
upnp_wps_device_init(struct upnp_wps_device_ctx *ctx, struct wps_context *wps,
		     void *priv, char *net_if)
{
	struct upnp_wps_device_sm *sm;
	struct upnp_wps_device_interface *iface;
	int start = 0;

	iface = os_zalloc(sizeof(*iface));
	if (iface == NULL) {
		os_free(ctx->ap_pin);
		os_free(ctx);
		return NULL;
	}
	wpa_printf(MSG_DEBUG, "WPS UPnP: Init interface instance %p", iface);

	dl_list_init(&iface->peers);
	iface->ctx = ctx;
	iface->wps = wps;
	iface->priv = priv;

	if (shared_upnp_device) {
		wpa_printf(MSG_DEBUG, "WPS UPnP: Share existing device "
			   "context");
		sm = shared_upnp_device;
	} else {
		wpa_printf(MSG_DEBUG, "WPS UPnP: Initialize device context");
		sm = os_zalloc(sizeof(*sm));
		if (!sm) {
			wpa_printf(MSG_ERROR, "WPS UPnP: upnp_wps_device_init "
				   "failed");
			os_free(iface);
			os_free(ctx->ap_pin);
			os_free(ctx);
			return NULL;
		}
		shared_upnp_device = sm;

		dl_list_init(&sm->msearch_replies);
		dl_list_init(&sm->subscriptions);
		dl_list_init(&sm->interfaces);
		start = 1;
	}

	dl_list_add(&sm->interfaces, &iface->list);

	if (start && upnp_wps_device_start(sm, net_if)) {
		upnp_wps_device_deinit(sm, priv);
		return NULL;
	}


	return sm;
}


/**
 * upnp_wps_subscribers - Check whether there are any event subscribers
 * @sm: WPS UPnP state machine from upnp_wps_device_init()
 * Returns: 0 if no subscribers, 1 if subscribers
 */
int upnp_wps_subscribers(struct upnp_wps_device_sm *sm)
{
	return !dl_list_empty(&sm->subscriptions);
}


int upnp_wps_set_ap_pin(struct upnp_wps_device_sm *sm, const char *ap_pin)
{
	struct upnp_wps_device_interface *iface;
	if (sm == NULL)
		return 0;

	dl_list_for_each(iface, &sm->interfaces,
			 struct upnp_wps_device_interface, list) {
		os_free(iface->ctx->ap_pin);
		if (ap_pin) {
			iface->ctx->ap_pin = os_strdup(ap_pin);
			if (iface->ctx->ap_pin == NULL)
				return -1;
		} else
			iface->ctx->ap_pin = NULL;
	}

	return 0;
}