radsecproxy.c 31.5 KB
Newer Older
venaas's avatar
 
venaas committed
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
/*
 * Copyright (C) 2006 Stig Venaas <venaas@uninett.no>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 */

/* BUGS:
 * peers can not yet be specified with literal IPv6 addresses due to port syntax
 */

/* TODO:
 * Among other things:
 * timer based client retrans or maybe no retrans and just a timer...
 * make our server ignore client retrans?
 * tls keep alives
 * routing based on id....
venaas's avatar
venaas committed
19
 * need to also encrypt Tunnel-Password and Message-Authenticator attrs
venaas's avatar
 
venaas committed
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
 * tls certificate validation
*/

/* For UDP there is one server instance consisting of udpserverrd and udpserverth
 *              rd is responsible for init and launching wr
 * For TLS there is a server instance that launches tlsserverrd for each TLS peer
 *          each tlsserverrd launches tlsserverwr
 * For each UDP/TLS peer there is clientrd and clientwr, clientwr is responsible
 *          for init and launching rd
 *
 * serverrd will receive a request, processes it and puts it in the requestq of
 *          the appropriate clientwr
 * clientwr monitors its requestq and sends requests
 * clientrd looks for responses, processes them and puts them in the replyq of
 *          the peer the request came from
 * serverwr monitors its reply and sends replies
 *
 * In addition to the main thread, we have:
 * If UDP peers are configured, there will be 2 + 2 * #peers UDP threads
 * If TLS peers are configured, there will initially be 2 * #peers TLS threads
 * For each TLS peer connecting to us there will be 2 more TLS threads
 *       This is only for connected peers
 * Example: With 3 UDP peer and 30 TLS peers, there will be a max of
 *          1 + (2 + 2 * 3) + (2 * 30) + (2 * 30) = 129 threads
*/

#include <netdb.h>
#include <unistd.h>
venaas's avatar
venaas committed
48
#include <sys/time.h>
venaas's avatar
 
venaas committed
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
#include <pthread.h>
#include <openssl/ssl.h>
#include <openssl/rand.h>
#include <openssl/err.h>
#include <openssl/md5.h>
#include "radsecproxy.h"

static struct peer peers[MAX_PEERS];
static int peer_count = 0;

static struct replyq udp_server_replyq;
static int udp_server_sock = -1;
static char *udp_server_port = DEFAULT_UDP_PORT;
static pthread_mutex_t *ssl_locks;
static long *ssl_lock_count;
static SSL_CTX *ssl_ctx_cl;
extern int optind;
extern char *optarg;

/* callbacks for making OpenSSL thread safe */
unsigned long ssl_thread_id() {
        return (unsigned long)pthread_self();
};

void ssl_locking_callback(int mode, int type, const char *file, int line) {
    if (mode & CRYPTO_LOCK) {
	pthread_mutex_lock(&ssl_locks[type]);
	ssl_lock_count[type]++;
    } else
	pthread_mutex_unlock(&ssl_locks[type]);
}

void ssl_locks_setup() {
    int i;

    ssl_locks = malloc(CRYPTO_num_locks() * sizeof(pthread_mutex_t));
    ssl_lock_count = OPENSSL_malloc(CRYPTO_num_locks() * sizeof(long));
    for (i = 0; i < CRYPTO_num_locks(); i++) {
	ssl_lock_count[i] = 0;
	pthread_mutex_init(&ssl_locks[i], NULL);
    }

    CRYPTO_set_id_callback(ssl_thread_id);
    CRYPTO_set_locking_callback(ssl_locking_callback);
}

int resolvepeer(struct peer *peer) {
    struct addrinfo hints;
    
    pthread_mutex_lock(&peer->lock);
    if (peer->addrinfo) {
	/* assume we should re-resolve */
	freeaddrinfo(peer->addrinfo);
	peer->addrinfo = NULL;
    }
    
    memset(&hints, 0, sizeof(hints));
    hints.ai_socktype = (peer->type == 'T' ? SOCK_STREAM : SOCK_DGRAM);
    hints.ai_family = AF_UNSPEC;
    if (getaddrinfo(peer->host, peer->port, &hints, &peer->addrinfo)) {
	err("resolvepeer: can't resolve %s port %s", peer->host, peer->port);
	peer->addrinfo = NULL; /* probably don't need this */
	pthread_mutex_unlock(&peer->lock);
	return 0;
    }
    pthread_mutex_unlock(&peer->lock);
    return 1;
}	  

int connecttopeer(struct peer *peer) {
    int s;
    struct addrinfo *res;
    
    if (!peer->addrinfo) {
	resolvepeer(peer);
	if (!peer->addrinfo) {
	    printf("connecttopeer: can't resolve %s into address to connect to\n", peer->host);
	    return -1;
	}
    }

    for (res = peer->addrinfo; res; res = res->ai_next) {
        s = socket(res->ai_family, res->ai_socktype, res->ai_protocol);
        if (s < 0) {
            err("connecttopeer: socket failed");
            continue;
        }
        if (connect(s, res->ai_addr, res->ai_addrlen) == 0)
            break;
        err("connecttopeer: connect failed");
        close(s);
        s = -1;
    }
    return s;
}	  

/* returns the peer with matching address, or NULL */
/* if peer argument is not NULL, we only check that one peer */
struct peer *find_peer(char type, struct sockaddr *addr, struct peer *peer) {
    struct sockaddr_in6 *sa6;
    struct in_addr *a4 = NULL;
    struct peer *p;
    int i;
    struct addrinfo *res;

    if (addr->sa_family == AF_INET6) {
        sa6 = (struct sockaddr_in6 *)addr;
        if (IN6_IS_ADDR_V4MAPPED(&sa6->sin6_addr))
            a4 = (struct in_addr *)&sa6->sin6_addr.s6_addr[12];
    } else
	a4 = &((struct sockaddr_in *)addr)->sin_addr;

    p = (peer ? peer : peers);
    for (i = 0; i < peer_count; i++) {
	if (p->type == type)
	    for (res = p->addrinfo; res; res = res->ai_next)
		if ((a4 && res->ai_family == AF_INET &&
		     !memcmp(a4, &((struct sockaddr_in *)res->ai_addr)->sin_addr, 4)) ||
		    (res->ai_family == AF_INET6 &&
		     !memcmp(&sa6->sin6_addr, &((struct sockaddr_in6 *)res->ai_addr)->sin6_addr, 16)))
		    return p;
	if (peer)
	    break;
	p++;
    }
    return NULL;
}

/* if *peer == NULL we return who we received from, else require it to be from peer */
/* return from in sa if not NULL */
unsigned char *radudpget(int s, struct peer **peer, struct sockaddr_storage *sa) {
    int cnt, len;
    struct peer *f;
    unsigned char buf[65536], *rad;
    struct sockaddr_storage from;
    socklen_t fromlen = sizeof(from);

    for (;;) {
	cnt = recvfrom(s, buf, sizeof(buf), 0, (struct sockaddr *)&from, &fromlen);
	if (cnt == -1) {
	    err("radudpget: recv failed");
	    continue;
	}
	printf("radudpget: got %d bytes from %s\n", cnt, addr2string((struct sockaddr *)&from, fromlen));

	if (cnt < 20) {
	    printf("radudpget: packet too small\n");
	    continue;
	}
    
	len = RADLEN(buf);

	if (cnt < len) {
	    printf("radudpget: packet smaller than length field in radius header\n");
	    continue;
	}
	if (cnt > len)
	    printf("radudpget: packet was padded with %d bytes\n", cnt - len);

	f = find_peer('U', (struct sockaddr *)&from, *peer);
	if (!f) {
	    printf("radudpget: got packet from wrong or unknown UDP peer, ignoring\n");
	    continue;
	}

	rad = malloc(len);
	if (rad)
	    break;
	err("radudpget: malloc failed");
    }
    memcpy(rad, buf, len);
    *peer = f; /* only need this if *peer == NULL, but if not NULL *peer == f here */
    if (sa)
	*sa = from;
    return rad;
}

venaas's avatar
venaas committed
226
227
228
229
void tlsconnect(struct peer *peer, struct timeval *when, char *text) {
    struct timeval now;
    time_t elapsed;
    unsigned long error;
venaas's avatar
 
venaas committed
230
231
    
    pthread_mutex_lock(&peer->lock);
venaas's avatar
venaas committed
232
    if (when && memcmp(&peer->lastconnecttry, when, sizeof(struct timeval))) {
venaas's avatar
 
venaas committed
233
	/* already reconnected, nothing to do */
venaas's avatar
venaas committed
234
	printf("tlsconnect: seems already reconnected\n");
venaas's avatar
 
venaas committed
235
236
237
238
	pthread_mutex_unlock(&peer->lock);
	return;
    }

venaas's avatar
venaas committed
239
240
    printf("tlsconnect %s\n", text);

venaas's avatar
 
venaas committed
241
242
    for (;;) {
	printf("tlsconnect: trying to open TLS connection to %s port %s\n", peer->host, peer->port);
venaas's avatar
venaas committed
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
	gettimeofday(&now, NULL);
	if (when) { // don't wait first time
	    elapsed = now.tv_sec - peer->lastconnecttry.tv_sec;
	    if (peer->connectionok) {
		peer->connectionok = 0;
		sleep(10);
	    } else if (elapsed < 5)
		sleep(10);
	    else if (elapsed < 600)
		sleep(elapsed * 2);
	    else
		sleep(900);
	}
	if (peer->sockcl >= 0)
	    close(peer->sockcl);
	if ((peer->sockcl = connecttopeer(peer)) < 0)
	    continue;
	SSL_free(peer->sslcl);
	peer->sslcl = SSL_new(ssl_ctx_cl);
	SSL_set_fd(peer->sslcl, peer->sockcl);
	if (SSL_connect(peer->sslcl) > 0)
venaas's avatar
 
venaas committed
264
	    break;
venaas's avatar
venaas committed
265
266
	while ((error = ERR_get_error()))
	    err("tlsconnect: TLS: %s", ERR_error_string(error, NULL));
venaas's avatar
 
venaas committed
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
    }
    printf("tlsconnect: TLS connection to %s port %s up\n", peer->host, peer->port);
    pthread_mutex_unlock(&peer->lock);
}

unsigned char *radtlsget(SSL *ssl) {
    int cnt, total, len;
    unsigned char buf[4], *rad;

    for (;;) {
	for (total = 0; total < 4; total += cnt) {
	    cnt = SSL_read(ssl, buf + total, 4 - total);
	    if (cnt <= 0) {
		printf("radtlsget: connection lost\n");
		return NULL;
	    }
	}

	len = RADLEN(buf);
	rad = malloc(len);
	if (!rad) {
	    err("radtlsget: malloc failed");
	    continue;
	}
	memcpy(rad, buf, 4);

	for (; total < len; total += cnt) {
	    cnt = SSL_read(ssl, rad + total, len - total);
	    if (cnt <= 0) {
		printf("radtlsget: connection lost\n");
		free(rad);
		return NULL;
	    }
	}
    
	if (total >= 20)
	    break;
	
	free(rad);
	printf("radtlsget: packet smaller than minimum radius size\n");
    }
    
    printf("radtlsget: got %d bytes\n", total);
    return rad;
}

int clientradput(struct peer *peer, unsigned char *rad) {
venaas's avatar
venaas committed
314
    int cnt;
venaas's avatar
 
venaas committed
315
316
    size_t len;
    unsigned long error;
venaas's avatar
venaas committed
317
318
    struct timeval lastconnecttry;
    
venaas's avatar
 
venaas committed
319
320
321
322
323
324
325
326
327
328
    len = RADLEN(rad);
    if (peer->type == 'U') {
	if (send(peer->sockcl, rad, len, 0) >= 0) {
	    printf("clienradput: sent UDP of length %d to %s port %s\n", len, peer->host, peer->port);
	    return 1;
	}
	err("clientradput: send failed");
	return 0;
    }

venaas's avatar
venaas committed
329
    lastconnecttry = peer->lastconnecttry;
venaas's avatar
 
venaas committed
330
331
332
    while ((cnt = SSL_write(peer->sslcl, rad, len)) <= 0) {
	while ((error = ERR_get_error()))
	    err("clientwr: TLS: %s", ERR_error_string(error, NULL));
venaas's avatar
venaas committed
333
334
	tlsconnect(peer, &lastconnecttry, "clientradput");
	lastconnecttry = peer->lastconnecttry;
venaas's avatar
 
venaas committed
335
    }
venaas's avatar
venaas committed
336
337

    peer->connectionok = 1;
venaas's avatar
 
venaas committed
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
    printf("clientradput: Sent %d bytes, Radius packet of length %d to TLS peer %s\n",
	   cnt, len, peer->host);
    return 1;
}

int radsign(unsigned char *rad, unsigned char *sec) {
    static pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;
    static unsigned char first = 1;
    static EVP_MD_CTX mdctx;
    unsigned int md_len;
    int result;
    
    pthread_mutex_lock(&lock);
    if (first) {
	EVP_MD_CTX_init(&mdctx);
	first = 0;
    }

    result = (EVP_DigestInit_ex(&mdctx, EVP_md5(), NULL) &&
	EVP_DigestUpdate(&mdctx, rad, RADLEN(rad)) &&
	EVP_DigestUpdate(&mdctx, sec, strlen(sec)) &&
	EVP_DigestFinal_ex(&mdctx, rad + 4, &md_len) &&
	md_len == 16);
    pthread_mutex_unlock(&lock);
    return result;
}

int validauth(unsigned char *rad, unsigned char *reqauth, unsigned char *sec) {
    static pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;
    static unsigned char first = 1;
    static EVP_MD_CTX mdctx;
    unsigned char hash[EVP_MAX_MD_SIZE];
    unsigned int len;
    int result;
    
    pthread_mutex_lock(&lock);
    if (first) {
	EVP_MD_CTX_init(&mdctx);
	first = 0;
    }

    len = RADLEN(rad);
    
    result = (EVP_DigestInit_ex(&mdctx, EVP_md5(), NULL) &&
	      EVP_DigestUpdate(&mdctx, rad, 4) &&
	      EVP_DigestUpdate(&mdctx, reqauth, 16) &&
	      (len <= 20 || EVP_DigestUpdate(&mdctx, rad + 20, len - 20)) &&
	      EVP_DigestUpdate(&mdctx, sec, strlen(sec)) &&
	      EVP_DigestFinal_ex(&mdctx, hash, &len) &&
	      len == 16 &&
	      !memcmp(hash, rad + 4, 16));
    pthread_mutex_unlock(&lock);
    return result;
}
	      
void sendrq(struct peer *to, struct peer *from, struct request *rq) {
    int i;

    pthread_mutex_lock(&to->newrq_mutex);
    for (i = 0; i < MAX_REQUESTS; i++)
	if (!to->requests[i].buf)
	    break;
    if (i == MAX_REQUESTS) {
	printf("No room in queue, dropping request\n");
	pthread_mutex_unlock(&to->newrq_mutex);
	return;
    }
    
    rq->buf[1] = (char)i;
    to->requests[i] = *rq;

    if (!to->newrq) {
	to->newrq = 1;
	printf("signalling client writer\n");
	pthread_cond_signal(&to->newrq_cond);
    }
    pthread_mutex_unlock(&to->newrq_mutex);
}

void sendreply(struct peer *to, struct peer *from, char *buf, struct sockaddr_storage *tosa) {
    struct replyq *replyq = to->replyq;
    
    pthread_mutex_lock(&replyq->count_mutex);
    if (replyq->count == replyq->size) {
	printf("No room in queue, dropping request\n");
	pthread_mutex_unlock(&replyq->count_mutex);
	return;
    }

    replyq->replies[replyq->count].buf = buf;
    if (tosa)
	replyq->replies[replyq->count].tosa = *tosa;
    replyq->count++;

    if (replyq->count == 1) {
	printf("signalling client writer\n");
	pthread_cond_signal(&replyq->count_cond);
    }
    pthread_mutex_unlock(&replyq->count_mutex);
}

int pwdcrypt(uint8_t *plain, uint8_t *enc, uint8_t enclen, uint8_t *shared, uint8_t sharedlen,
		uint8_t *auth) {
    static pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;
    static unsigned char first = 1;
    static EVP_MD_CTX mdctx;
    unsigned char hash[EVP_MAX_MD_SIZE], *input;
    unsigned int md_len;
    uint8_t i, offset = 0;
    
    pthread_mutex_lock(&lock);
    if (first) {
	EVP_MD_CTX_init(&mdctx);
	first = 0;
    }

    input = auth;
    for (;;) {
	if (!EVP_DigestInit_ex(&mdctx, EVP_md5(), NULL) ||
	    !EVP_DigestUpdate(&mdctx, shared, sharedlen) ||
	    !EVP_DigestUpdate(&mdctx, input, 16) ||
	    !EVP_DigestFinal_ex(&mdctx, hash, &md_len) ||
	    md_len != 16) {
	    pthread_mutex_unlock(&lock);
	    return 0;
	}
	for (i = 0; i < 16; i++)
	    plain[offset + i] = hash[i] ^ enc[offset + i];
	offset += 16;
	if (offset == enclen)
	    break;
	input = enc + offset - 16;
    }
    pthread_mutex_unlock(&lock);
    return 1;
}

struct peer *radsrv(struct request *rq, char *buf, struct peer *from) {
    uint8_t code, id, *auth, *attr, *usernameattr = NULL, *userpwdattr = NULL, pwd[128], pwdlen;
    int i;
    uint16_t len;
    int left;
    struct peer *to;
    unsigned char newauth[16];
    
    code = *(uint8_t *)buf;
    id = *(uint8_t *)(buf + 1);
    len = RADLEN(buf);
    auth = (uint8_t *)(buf + 4);

    printf("radsrv: code %d, id %d, length %d\n", code, id, len);
    
    if (code != RAD_Access_Request) {
	printf("radsrv: server currently accepts only access-requests, ignoring\n");
	return NULL;
    }

    left = len - 20;
    attr = buf + 20;
    
    while (left > 1) {
	left -= attr[RAD_Attr_Length];
	if (left < 0) {
	    printf("radsrv: attribute length exceeds packet length, ignoring packet\n");
	    return NULL;
	}
	switch (attr[RAD_Attr_Type]) {
	case RAD_Attr_User_Name:
	    usernameattr = attr;
	    break;
	case RAD_Attr_User_Password:
	    userpwdattr = attr;
	    break;
	}
	attr += attr[RAD_Attr_Length];
    }
    if (left)
	printf("radsrv: malformed packet? remaining byte after last attribute\n");

    if (usernameattr) {
	printf("radsrv: Username: ");
	for (i = 0; i < usernameattr[RAD_Attr_Length]; i++)
	    printf("%c", usernameattr[RAD_Attr_Value + i]);
	printf("\n");
    }

    /* find out where to send the packet, for now we send to first connected
       TLS peer if UDP, and first UDP peer if TLS */
    
    i = peer_count;
    switch (from->type) {
    case 'U':
	for (i = 0; i < peer_count; i++)
	    if (peers[i].type == 'T' && peers[i].sockcl >= 0)
		break;
	break;
    case 'T':
	for (i = 0; i < peer_count; i++)
	    if (peers[i].type == 'U')
		break;
	break;
    }

    if (i == peer_count) {
	printf("radsrv: ignoring request, don't know where to send it\n");
	return NULL;
    }

    to = &peers[i];
    
    if (!RAND_bytes(newauth, 16)) {
	printf("radsrv: failed to generate random auth\n");
	return NULL;
    }

    if (userpwdattr) {
	printf("radsrv: found userpwdattr of length %d\n", userpwdattr[RAD_Attr_Length]);
	pwdlen = userpwdattr[RAD_Attr_Length] - 2;
	if (pwdlen < 16 || pwdlen > 128 || pwdlen % 16) {
	    printf("radsrv: invalid user password length\n");
	    return NULL;
	}
	
	if (!pwdcrypt(pwd, &userpwdattr[RAD_Attr_Value], pwdlen, from->secret, strlen(from->secret), auth)) {
	    printf("radsrv: cannot decrypt password\n");
	    return NULL;
	}
	printf("radsrv: password: ");
	for (i = 0; i < pwdlen; i++)
	    printf("%02x ", pwd[i]);
	printf("\n");
	if (!pwdcrypt(&userpwdattr[RAD_Attr_Value], pwd, pwdlen, to->secret, strlen(to->secret), newauth)) {
	    printf("radsrv: cannot encrypt password\n");
	    return NULL;
	}
    }

    rq->buf = buf;
    rq->from = from;
    rq->origid = id;
    memcpy(rq->origauth, auth, 16);
    memcpy(rq->buf + 4, newauth, 16);
    return to;
}

void *clientrd(void *arg) {
    struct peer *from, *peer = (struct peer *)arg;
venaas's avatar
venaas committed
585
    int i;
venaas's avatar
 
venaas committed
586
587
    unsigned char *buf;
    struct sockaddr_storage fromsa;
venaas's avatar
venaas committed
588
    struct timeval lastconnecttry;
venaas's avatar
 
venaas committed
589
590
    
    for (;;) {
venaas's avatar
venaas committed
591
592
	lastconnecttry = peer->lastconnecttry;
	buf = (peer->type == 'U' ? radudpget(peer->sockcl, &peer, NULL) : radtlsget(peer->sslcl));
venaas's avatar
 
venaas committed
593
594
595
	if (!buf && peer->type == 'T') {
	    printf("retry in 60s\n");
	    sleep(60); /* should have exponential backoff perhaps, better do it inside radtlsget */
venaas's avatar
venaas committed
596
	    tlsconnect(peer, &lastconnecttry, "clientrd");
venaas's avatar
 
venaas committed
597
598
	    continue;
	}
venaas's avatar
venaas committed
599
600

	peer->connectionok = 1;
venaas's avatar
 
venaas committed
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
	
	i = buf[1]; /* i is the id */

	pthread_mutex_lock(&peer->newrq_mutex);
	if (!peer->requests[i].buf || !peer->requests[i].tries) {
	    pthread_mutex_unlock(&peer->newrq_mutex);
	    printf("clientrd: no matching request sent with this id, ignoring\n");
	    continue;
	}
        
	if (peer->requests[i].received) {
	    pthread_mutex_unlock(&peer->newrq_mutex);
	    printf("clientrd: already received, ignoring\n");
	    continue;
	}

	if (!validauth(buf, peer->requests[i].buf + 4, peer->secret)) {
	    pthread_mutex_unlock(&peer->newrq_mutex);
	    printf("clientrd: invalid auth, ignoring\n");
	    continue;
	}

	/* once we set received = 1, requests[i] may be reused */
	buf[1] = (char)peer->requests[i].origid;
	memcpy(buf + 4, peer->requests[i].origauth, 16);
	from = peer->requests[i].from;
	if (from->type == 'U')
	    fromsa = peer->requests[i].fromsa;
	peer->requests[i].received = 1;
	pthread_mutex_unlock(&peer->newrq_mutex);

	if (!radsign(buf, from->secret)) {
	    printf("clientrd: failed to sign message\n");
	    continue;
	}
	
	printf("clientrd: giving packet back to where it came from\n");
	sendreply(from, peer, buf, from->type == 'U' ? &fromsa : NULL);
    }
}

void *clientwr(void *arg) {
    struct peer *peer = (struct peer *)arg;
    pthread_t clientrdth;
    int i;

    if (peer->type == 'U') {
	if ((peer->sockcl = connecttopeer(peer)) < 0) {
	    printf("clientwr: connecttopeer failed\n");
	    exit(1);
	}
    } else
venaas's avatar
venaas committed
653
	tlsconnect(peer, NULL, "new client");
venaas's avatar
 
venaas committed
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
    
    if (pthread_create(&clientrdth, NULL, clientrd, (void *)peer))
	errx("clientwr: pthread_create failed");

    for (;;) {
	pthread_mutex_lock(&peer->newrq_mutex);
	while (!peer->newrq) {
	    printf("clientwr: waiting for signal\n");
	    pthread_cond_wait(&peer->newrq_cond, &peer->newrq_mutex);
	    printf("clientwr: got signal\n");
	}
	peer->newrq = 0;
	pthread_mutex_unlock(&peer->newrq_mutex);
	       
	for (i = 0; i < MAX_REQUESTS; i++) {
	    pthread_mutex_lock(&peer->newrq_mutex);
	    while (!peer->requests[i].buf && i < MAX_REQUESTS)
		i++;
	    if (i == MAX_REQUESTS) {
		pthread_mutex_unlock(&peer->newrq_mutex);
		break;
	    }

	    /* already received or too many tries */
            if (peer->requests[i].received || peer->requests[i].tries > 2) {
                free(peer->requests[i].buf);
                /* setting this to NULL means that it can be reused */
                peer->requests[i].buf = NULL;
                pthread_mutex_unlock(&peer->newrq_mutex);
                continue;
            }
            pthread_mutex_unlock(&peer->newrq_mutex);
            
            peer->requests[i].tries++;
	    clientradput(peer, peer->requests[i].buf);
	}
    }
    /* should do more work to maintain TLS connections, keepalives etc */
}

void *udpserverwr(void *arg) {
    struct replyq *replyq = &udp_server_replyq;
    struct reply *reply = replyq->replies;
    
    pthread_mutex_lock(&replyq->count_mutex);
    for (;;) {
	while (!replyq->count) {
	    printf("udp server writer, waiting for signal\n");
	    pthread_cond_wait(&replyq->count_cond, &replyq->count_mutex);
	    printf("udp server writer, got signal\n");
	}
	pthread_mutex_unlock(&replyq->count_mutex);
	
	if (sendto(udp_server_sock, reply->buf, RADLEN(reply->buf), 0,
		   (struct sockaddr *)&reply->tosa, SOCKADDR_SIZE(reply->tosa)) < 0)
	    err("sendudp: send failed");
	free(reply->buf);
	
	pthread_mutex_lock(&replyq->count_mutex);
	replyq->count--;
	memmove(replyq->replies, replyq->replies + 1,
		replyq->count * sizeof(struct reply));
    }
}

void *udpserverrd(void *arg) {
    struct request rq;
    unsigned char *buf;
    struct peer *to, *fr;
    pthread_t udpserverwrth;
    
    if ((udp_server_sock = bindport(SOCK_DGRAM, udp_server_port)) < 0) {
        printf("udpserverrd: socket/bind failed\n");
	exit(1);
    }
    printf("udpserverrd: listening on UDP port %s\n", udp_server_port);

    if (pthread_create(&udpserverwrth, NULL, udpserverwr, NULL))
	errx("pthread_create failed");
    
    for (;;) {
	fr = NULL;
	memset(&rq, 0, sizeof(struct request));
	buf = radudpget(udp_server_sock, &fr, &rq.fromsa);
	to = radsrv(&rq, buf, fr);
	if (!to) {
	    printf("udpserverrd: ignoring request, no place to send it\n");
	    continue;
	}
	sendrq(to, fr, &rq);
    }
}

void *tlsserverwr(void *arg) {
    int cnt;
    unsigned long error;
    struct peer *peer = (struct peer *)arg;
    struct replyq *replyq;
    
    pthread_mutex_lock(&peer->replycount_mutex);
    for (;;) {
	replyq = peer->replyq;
	while (!replyq->count) {
	    printf("tls server writer, waiting for signal\n");
	    pthread_cond_wait(&replyq->count_cond, &replyq->count_mutex);
	    printf("tls server writer, got signal\n");
	}
	pthread_mutex_unlock(&replyq->count_mutex);
	cnt = SSL_write(peer->sslsrv, replyq->replies->buf, RADLEN(replyq->replies->buf));
	if (cnt > 0)
	    printf("tlsserverwr: Sent %d bytes, Radius packet of length %d\n",
		   cnt, RADLEN(replyq->replies->buf));
	else
	    while ((error = ERR_get_error()))
		err("tlsserverwr: SSL: %s", ERR_error_string(error, NULL));
	free(replyq->replies->buf);

	pthread_mutex_lock(&replyq->count_mutex);
	replyq->count--;
	memmove(replyq->replies, replyq->replies + 1, replyq->count * sizeof(struct reply));
    }
}

void *tlsserverrd(void *arg) {
    struct request rq;
    char unsigned *buf;
    unsigned long error;
    struct peer *to;
    int s;
    struct peer *peer = (struct peer *)arg;
    pthread_t tlsserverwrth;

    printf("tlsserverrd starting\n");
    if (SSL_accept(peer->sslsrv) <= 0) {
        while ((error = ERR_get_error()))
            err("tlsserverrd: SSL: %s", ERR_error_string(error, NULL));
        errx("accept failed, child exiting");
    }

    if (pthread_create(&tlsserverwrth, NULL, tlsserverwr, (void *)peer))
	errx("pthread_create failed");
    
    for (;;) {
	buf = radtlsget(peer->sslsrv);
	if (!buf) {
	    printf("tlsserverrd: connection lost\n");
	    s = SSL_get_fd(peer->sslsrv);
	    SSL_free(peer->sslsrv);
	    peer->sslsrv = NULL;
	    if (s >= 0)
		close(s);
	    pthread_exit(NULL);
	}
	printf("tlsserverrd: got Radius message from %s\n", peer->host);
	memset(&rq, 0, sizeof(struct request));
	to = radsrv(&rq, buf, peer);
	if (!to) {
	    printf("ignoring request, no place to send it\n");
	    continue;
	}
	sendrq(to, peer, &rq);
    }
}

int tlslistener(SSL_CTX *ssl_ctx) {
    pthread_t tlsserverth;
    int s, snew;
    struct sockaddr_storage from;
    size_t fromlen = sizeof(from);
    struct peer *peer;

    if ((s = bindport(SOCK_STREAM, DEFAULT_TLS_PORT)) < 0) {
        printf("tlslistener: socket/bind failed\n");
	exit(1);
    }

    listen(s, 0);
    printf("listening for incoming TLS on port %s\n", DEFAULT_TLS_PORT);

    for (;;) {
	snew = accept(s, (struct sockaddr *)&from, &fromlen);
	if (snew < 0)
	    errx("accept failed");
	printf("incoming TLS connection from %s\n", addr2string((struct sockaddr *)&from, fromlen));

	peer = find_peer('T', (struct sockaddr *)&from, NULL);
	if (!peer) {
	    printf("ignoring request, not a known TLS peer\n");
	    close(snew);
	    continue;
	}

	if (peer->sslsrv) {
	    printf("Ignoring incoming connection, already have one from this peer\n");
	    close(snew);
	    continue;
	}
	peer->sslsrv = SSL_new(ssl_ctx);
	SSL_set_fd(peer->sslsrv, snew);
	if (pthread_create(&tlsserverth, NULL, tlsserverrd, (void *)peer))
	    errx("pthread_create failed");
	
	for (;;) {
	    /* currently only one server thread, so just halt here */
	    sleep(1000);
	}
    }
    return 0;
}

venaas's avatar
   
venaas committed
864
char *parsehostport(char *s, struct peer *peer) {
venaas's avatar
 
venaas committed
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
    char *p, *field;
    int ipv6 = 0;

    p = s;
    // allow literal addresses and port, e.g. [2001:db8::1]:1812
    if (*p == '[') {
	p++;
	field = p;
	for (; *p && *p != ']' && *p != ' ' && *p != '\t' && *p != '\n'; p++);
	if (*p != ']') {
	    printf("no ] matching initial [\n");
	    exit(1);
	}
	ipv6 = 1;
    } else {
	field = p;
	for (; *p && *p != ':' && *p != ' ' && *p != '\t' && *p != '\n'; p++);
    }
    if (field == p) {
	printf("missing host/address\n");
	exit(1);
    }
venaas's avatar
   
venaas committed
887
888
    peer->host = malloc(p - field + 1);
    if (!peer->host)
venaas's avatar
 
venaas committed
889
	errx("malloc failed");
venaas's avatar
   
venaas committed
890
891
    memcpy(peer->host, field, p - field);
    peer->host[p - field] = '\0';
venaas's avatar
 
venaas committed
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
    if (ipv6) {
	p++;
	if (*p && *p != ':' && *p != ' ' && *p != '\t' && *p != '\n') {
	    printf("unexpected character after ]\n");
	    exit(1);
	}
    }
    if (*p == ':') {
	    /* port number or service name is specified */;
	    field = p++;
	    for (; *p && *p != ' ' && *p != '\t' && *p != '\n'; p++);
	    if (field == p) {
		printf("syntax error, : but no following port\n");
		exit(1);
	    }
venaas's avatar
   
venaas committed
907
908
	    peer->port = malloc(p - field + 1);
	    if (!peer->port)
venaas's avatar
 
venaas committed
909
		errx("malloc failed");
venaas's avatar
   
venaas committed
910
911
	    memcpy(peer->port, field, p - field);
	    peer->port[p - field] = '\0';
venaas's avatar
 
venaas committed
912
    } else
venaas's avatar
   
venaas committed
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
        peer->port = NULL;
    return p;
}

// * is default, else longest match ... ";" used for separator
char *parserealmlist(char *s, struct peer *peer) {
    char *p;
    int i, n, l;

    for (p = s, n = 1; *p && *p != ' ' && *p != '\t' && *p != '\n'; p++)
	if (*p == ';')
	    n++;
    l = p - s;
    if (!l) {
	peer->realms = NULL;
	return p;
    }
    peer->realmdata = malloc(l + 1);
    if (!peer->realmdata)
	errx("malloc failed");
    memcpy(peer->realmdata, s, l);
    peer->realmdata[l] = '\0';
    peer->realms = malloc((1+n) * sizeof(char *));
    if (!peer->realms)
	errx("malloc failed");
    peer->realms[0] = peer->realmdata;
    for (n = 1, i = 0; i < l; i++)
	if (peer->realmdata[i] == ';') {
	    peer->realmdata[i] = '\0';
	    peer->realms[n++] = peer->realmdata + i + 1;
	}	
    peer->realms[n] = NULL;
venaas's avatar
 
venaas committed
945
946
947
948
949
950
    return p;
}

void getconfig(const char *filename) {
    FILE *f;
    char line[1024];
venaas's avatar
   
venaas committed
951
    char *p, *field, **r;
venaas's avatar
 
venaas committed
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
    struct peer *peer;
    
    peer_count = 0;
    
    udp_server_replyq.replies = malloc(4 * MAX_REQUESTS * sizeof(struct reply));
    if (!udp_server_replyq.replies)
	errx("malloc failed");
    udp_server_replyq.size = 4 * MAX_REQUESTS;
    udp_server_replyq.count = 0;
    pthread_mutex_init(&udp_server_replyq.count_mutex, NULL);
    pthread_cond_init(&udp_server_replyq.count_cond, NULL);
    
    f = fopen(filename, "r");
    if (!f)
	errx("getconfig failed to open %s for reading", filename);

    while (fgets(line, 1024, f) && peer_count < MAX_PEERS) {
	peer = &peers[peer_count];
	memset(peer, 0, sizeof(struct peer));

	for (p = line; *p == ' ' || *p == '\t'; p++);
	if (*p == '#' || *p == '\n')
	    continue;
	if (*p != 'U' && *p != 'T') {
	    printf("server type must be U or T, got %c\n", *p);
	    exit(1);
	}
	peer->type = *p;
	for (p++; *p == ' ' || *p == '\t'; p++);
venaas's avatar
   
venaas committed
981
	p = parsehostport(p, peer);
venaas's avatar
 
venaas committed
982
983
984
	if (!peer->port)
	    peer->port = (peer->type == 'U' ? DEFAULT_UDP_PORT : DEFAULT_TLS_PORT);
	for (; *p == ' ' || *p == '\t'; p++);
venaas's avatar
   
venaas committed
985
986
987
988
989
990
	p = parserealmlist(p, peer);
	if (!peer->realms) {
	    printf("realm list must be specified\n");
	    exit(1);
	}
	for (; *p == ' ' || *p == '\t'; p++);
venaas's avatar
 
venaas committed
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
	field = p;
	for (; *p && *p != ' ' && *p != '\t' && *p != '\n'; p++);
	if (field == p) {
	    /* no secret set and end of line, line is complete if TLS */
	    if (peer->type == 'U') {
		printf("secret must be specified for UDP\n");
		exit(1);
	    }
	    peer->secret = DEFAULT_TLS_SECRET;
	} else {
	    peer->secret = malloc(p - field + 1);
	    if (!peer->secret)
		errx("malloc failed");
	    memcpy(peer->secret, field, p - field);
	    peer->secret[p - field] = '\0';
	    /* check that rest of line only white space */
	    for (; *p == ' ' || *p == '\t'; p++);
	    if (*p && *p != '\n') {
venaas's avatar
   
venaas committed
1009
		printf("max 4 fields per line, found a 5th\n");
venaas's avatar
 
venaas committed
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
		exit(1);
	    }
	}
	peer->sockcl = -1;
	pthread_mutex_init(&peer->lock, NULL);
	if (!resolvepeer(peer)) {
	    printf("failed to resolve host %s port %s, exiting\n", peer->host, peer->port);
	    exit(1);
	}
	peer->requests = malloc(MAX_REQUESTS * sizeof(struct request));
	if (!peer->requests)
	    errx("malloc failed");
	memset(peer->requests, 0, MAX_REQUESTS * sizeof(struct request));
	peer->newrq = 0;
	pthread_mutex_init(&peer->newrq_mutex, NULL);
	pthread_cond_init(&peer->newrq_cond, NULL);

	if (peer->type == 'U')
	    peer->replyq = &udp_server_replyq;
	else {
	    peer->replyq = malloc(sizeof(struct replyq));
	    if (!peer->replyq)
		errx("malloc failed");
	    peer->replyq->replies = malloc(MAX_REQUESTS * sizeof(struct reply));
	    if (!peer->replyq->replies)
		errx("malloc failed");
	    peer->replyq->size = MAX_REQUESTS;
	    peer->replyq->count = 0;
	    pthread_mutex_init(&peer->replyq->count_mutex, NULL);
	    pthread_cond_init(&peer->replyq->count_cond, NULL);
	}
	printf("got type %c, host %s, port %s, secret %s\n", peers[peer_count].type,
	       peers[peer_count].host, peers[peer_count].port, peers[peer_count].secret);
venaas's avatar
   
venaas committed
1043
1044
1045
1046
	printf("    with realms:");
	for (r = peer->realms; *r; r++)
	    printf(" %s", *r);
	printf("\n");
venaas's avatar
 
venaas committed
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
	peer_count++;
    }
    fclose(f);
}

void parseargs(int argc, char **argv) {
    int c;

    while ((c = getopt(argc, argv, "p:")) != -1) {
	switch (c) {
	case 'p':
	    udp_server_port = optarg;
	    break;
	default:
	    goto usage;
	}
    }

    return;

 usage:
    printf("radsecproxy [ -p UDP-port ]\n");
    exit(1);
}
	       
int main(int argc, char **argv) {
    SSL_CTX *ssl_ctx_srv;
    unsigned long error;
    pthread_t udpserverth;
    pthread_attr_t joinable;
    int i;
    
    parseargs(argc, argv);
    getconfig("radsecproxy.conf");
    
    ssl_locks_setup();

    pthread_attr_init(&joinable);
    pthread_attr_setdetachstate(&joinable, PTHREAD_CREATE_JOINABLE);
   
    /* listen on UDP if at least one UDP peer */
    
    for (i = 0; i < peer_count; i++)
	if (peers[i].type == 'U') {
	    if (pthread_create(&udpserverth, &joinable, udpserverrd, NULL))
		errx("pthread_create failed");
	    break;
	}
    
    for (i = 0; i < peer_count; i++)
	if (peers[i].type == 'T')
	    break;

    if (i == peer_count) {
	printf("No TLS peers defined, just doing UDP proxying\n");
	/* just hang around doing nothing, anything to do here? */
	pthread_join(udpserverth, NULL);
	return 0;
    }
    
    /* SSL setup */
    SSL_load_error_strings();
    SSL_library_init();

    while (!RAND_status()) {
	time_t t = time(NULL);
	pid_t pid = getpid();
	RAND_seed((unsigned char *)&t, sizeof(time_t));
        RAND_seed((unsigned char *)&pid, sizeof(pid));
    }
    
    /* initialise client part and start clients */
    ssl_ctx_cl = SSL_CTX_new(TLSv1_client_method());
    if (!ssl_ctx_cl)
	errx("no ssl ctx");
    
    for (i = 0; i < peer_count; i++) {
	if (pthread_create(&peers[i].clientth, NULL, clientwr, (void *)&peers[i]))
	    errx("pthread_create failed");
    }

    /* setting up server/daemon part */
    ssl_ctx_srv = SSL_CTX_new(TLSv1_server_method());
    if (!ssl_ctx_srv)
	errx("no ssl ctx");
    if (!SSL_CTX_use_certificate_file(ssl_ctx_srv, "/tmp/server.pem", SSL_FILETYPE_PEM)) {
        while ((error = ERR_get_error()))
            err("SSL: %s", ERR_error_string(error, NULL));
        errx("Failed to load certificate");
    }
    if (!SSL_CTX_use_PrivateKey_file(ssl_ctx_srv, "/tmp/server.key", SSL_FILETYPE_PEM)) {
	while ((error = ERR_get_error()))
	    err("SSL: %s", ERR_error_string(error, NULL));
	errx("Failed to load private key");
    }
    return tlslistener(ssl_ctx_srv);
}