/* [<][>][^][v][top][bottom][index][help] */
DEFINITIONS
This source file includes following definitions.
- recv_loop
- send_and_recv_udp
- send_and_recv_tcp
- _krb5_send_and_recv_tcp
- send_and_recv_http
- init_port
- send_via_proxy
- send_via_plugin
- krb5_sendto
- krb5_sendto_kdc
- krb5_sendto_kdc_flags
- krb5_set_send_to_kdc_func
- _krb5_copy_send_to_kdc_func
- krb5_sendto_ctx_alloc
- krb5_sendto_ctx_add_flags
- krb5_sendto_ctx_get_flags
- krb5_sendto_ctx_set_type
- krb5_sendto_ctx_set_func
- krb5_sendto_ctx_free
- krb5_sendto_context
- _krb5_kdc_retry
1 /*
2 * Copyright (c) 1997 - 2002 Kungliga Tekniska Högskolan
3 * (Royal Institute of Technology, Stockholm, Sweden).
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 *
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 *
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 *
17 * 3. Neither the name of the Institute nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34 #include "krb5_locl.h"
35 #include "send_to_kdc_plugin.h"
36
37 RCSID("$Id$");
38
39 struct send_to_kdc {
40 krb5_send_to_kdc_func func;
41 void *data;
42 };
43
44 /*
45 * send the data in `req' on the socket `fd' (which is datagram iff udp)
46 * waiting `tmout' for a reply and returning the reply in `rep'.
47 * iff limit read up to this many bytes
48 * returns 0 and data in `rep' if succesful, otherwise -1
49 */
50
51 static int
52 recv_loop (int fd,
/* [<][>][^][v][top][bottom][index][help] */
53 time_t tmout,
54 int udp,
55 size_t limit,
56 krb5_data *rep)
57 {
58 fd_set fdset;
59 struct timeval timeout;
60 int ret;
61 int nbytes;
62
63 if (fd >= FD_SETSIZE) {
64 return -1;
65 }
66
67 krb5_data_zero(rep);
68 do {
69 FD_ZERO(&fdset);
70 FD_SET(fd, &fdset);
71 timeout.tv_sec = tmout;
72 timeout.tv_usec = 0;
73 ret = select (fd + 1, &fdset, NULL, NULL, &timeout);
74 if (ret < 0) {
75 if (errno == EINTR)
76 continue;
77 return -1;
78 } else if (ret == 0) {
79 return 0;
80 } else {
81 void *tmp;
82
83 if (ioctl (fd, FIONREAD, &nbytes) < 0) {
84 krb5_data_free (rep);
85 return -1;
86 }
87 if(nbytes <= 0)
88 return 0;
89
90 if (limit)
91 nbytes = min(nbytes, limit - rep->length);
92
93 tmp = realloc (rep->data, rep->length + nbytes);
94 if (tmp == NULL) {
95 krb5_data_free (rep);
96 return -1;
97 }
98 rep->data = tmp;
99 ret = recv (fd, (char*)tmp + rep->length, nbytes, 0);
100 if (ret < 0) {
101 krb5_data_free (rep);
102 return -1;
103 }
104 rep->length += ret;
105 }
106 } while(!udp && (limit == 0 || rep->length < limit));
107 return 0;
108 }
109
110 /*
111 * Send kerberos requests and receive a reply on a udp or any other kind
112 * of a datagram socket. See `recv_loop'.
113 */
114
115 static int
116 send_and_recv_udp(int fd,
/* [<][>][^][v][top][bottom][index][help] */
117 time_t tmout,
118 const krb5_data *req,
119 krb5_data *rep)
120 {
121 if (send (fd, req->data, req->length, 0) < 0)
122 return -1;
123
124 return recv_loop(fd, tmout, 1, 0, rep);
125 }
126
127 /*
128 * `send_and_recv' for a TCP (or any other stream) socket.
129 * Since there are no record limits on a stream socket the protocol here
130 * is to prepend the request with 4 bytes of its length and the reply
131 * is similarly encoded.
132 */
133
134 static int
135 send_and_recv_tcp(int fd,
/* [<][>][^][v][top][bottom][index][help] */
136 time_t tmout,
137 const krb5_data *req,
138 krb5_data *rep)
139 {
140 unsigned char len[4];
141 unsigned long rep_len;
142 krb5_data len_data;
143
144 _krb5_put_int(len, req->length, 4);
145 if(net_write(fd, len, sizeof(len)) < 0)
146 return -1;
147 if(net_write(fd, req->data, req->length) < 0)
148 return -1;
149 if (recv_loop (fd, tmout, 0, 4, &len_data) < 0)
150 return -1;
151 if (len_data.length != 4) {
152 krb5_data_free (&len_data);
153 return -1;
154 }
155 _krb5_get_int(len_data.data, &rep_len, 4);
156 krb5_data_free (&len_data);
157 if (recv_loop (fd, tmout, 0, rep_len, rep) < 0)
158 return -1;
159 if(rep->length != rep_len) {
160 krb5_data_free (rep);
161 return -1;
162 }
163 return 0;
164 }
165
166 int
167 _krb5_send_and_recv_tcp(int fd,
/* [<][>][^][v][top][bottom][index][help] */
168 time_t tmout,
169 const krb5_data *req,
170 krb5_data *rep)
171 {
172 return send_and_recv_tcp(fd, tmout, req, rep);
173 }
174
175 /*
176 * `send_and_recv' tailored for the HTTP protocol.
177 */
178
179 static int
180 send_and_recv_http(int fd,
/* [<][>][^][v][top][bottom][index][help] */
181 time_t tmout,
182 const char *prefix,
183 const krb5_data *req,
184 krb5_data *rep)
185 {
186 char *request;
187 char *str;
188 int ret;
189 int len = base64_encode(req->data, req->length, &str);
190
191 if(len < 0)
192 return -1;
193 asprintf(&request, "GET %s%s HTTP/1.0\r\n\r\n", prefix, str);
194 free(str);
195 if (request == NULL)
196 return -1;
197 ret = net_write (fd, request, strlen(request));
198 free (request);
199 if (ret < 0)
200 return ret;
201 ret = recv_loop(fd, tmout, 0, 0, rep);
202 if(ret)
203 return ret;
204 {
205 unsigned long rep_len;
206 char *s, *p;
207
208 s = realloc(rep->data, rep->length + 1);
209 if (s == NULL) {
210 krb5_data_free (rep);
211 return -1;
212 }
213 s[rep->length] = 0;
214 p = strstr(s, "\r\n\r\n");
215 if(p == NULL) {
216 krb5_data_zero(rep);
217 free(s);
218 return -1;
219 }
220 p += 4;
221 rep->data = s;
222 rep->length -= p - s;
223 if(rep->length < 4) { /* remove length */
224 krb5_data_zero(rep);
225 free(s);
226 return -1;
227 }
228 rep->length -= 4;
229 _krb5_get_int(p, &rep_len, 4);
230 if (rep_len != rep->length) {
231 krb5_data_zero(rep);
232 free(s);
233 return -1;
234 }
235 memmove(rep->data, p + 4, rep->length);
236 }
237 return 0;
238 }
239
240 static int
241 init_port(const char *s, int fallback)
/* [<][>][^][v][top][bottom][index][help] */
242 {
243 if (s) {
244 int tmp;
245
246 sscanf (s, "%d", &tmp);
247 return htons(tmp);
248 } else
249 return fallback;
250 }
251
252 /*
253 * Return 0 if succesful, otherwise 1
254 */
255
256 static int
257 send_via_proxy (krb5_context context,
/* [<][>][^][v][top][bottom][index][help] */
258 const krb5_krbhst_info *hi,
259 const krb5_data *send_data,
260 krb5_data *receive)
261 {
262 char *proxy2 = strdup(context->http_proxy);
263 char *proxy = proxy2;
264 char *prefix;
265 char *colon;
266 struct addrinfo hints;
267 struct addrinfo *ai, *a;
268 int ret;
269 int s = -1;
270 char portstr[NI_MAXSERV];
271
272 if (proxy == NULL)
273 return ENOMEM;
274 if (strncmp (proxy, "http://", 7) == 0)
275 proxy += 7;
276
277 colon = strchr(proxy, ':');
278 if(colon != NULL)
279 *colon++ = '\0';
280 memset (&hints, 0, sizeof(hints));
281 hints.ai_family = PF_UNSPEC;
282 hints.ai_socktype = SOCK_STREAM;
283 snprintf (portstr, sizeof(portstr), "%d",
284 ntohs(init_port (colon, htons(80))));
285 ret = getaddrinfo (proxy, portstr, &hints, &ai);
286 free (proxy2);
287 if (ret)
288 return krb5_eai_to_heim_errno(ret, errno);
289
290 for (a = ai; a != NULL; a = a->ai_next) {
291 s = socket (a->ai_family, a->ai_socktype, a->ai_protocol | SOCK_CLOEXEC);
292 if (s < 0)
293 continue;
294 rk_cloexec(s);
295 if (connect (s, a->ai_addr, a->ai_addrlen) < 0) {
296 close (s);
297 continue;
298 }
299 break;
300 }
301 if (a == NULL) {
302 freeaddrinfo (ai);
303 return 1;
304 }
305 freeaddrinfo (ai);
306
307 asprintf(&prefix, "http://%s/", hi->hostname);
308 if(prefix == NULL) {
309 close(s);
310 return 1;
311 }
312 ret = send_and_recv_http(s, context->kdc_timeout,
313 prefix, send_data, receive);
314 close (s);
315 free(prefix);
316 if(ret == 0 && receive->length != 0)
317 return 0;
318 return 1;
319 }
320
321 static krb5_error_code
322 send_via_plugin(krb5_context context,
/* [<][>][^][v][top][bottom][index][help] */
323 krb5_krbhst_info *hi,
324 time_t timeout,
325 const krb5_data *send_data,
326 krb5_data *receive)
327 {
328 struct krb5_plugin *list = NULL, *e;
329 krb5_error_code ret;
330
331 ret = _krb5_plugin_find(context, PLUGIN_TYPE_DATA, KRB5_PLUGIN_SEND_TO_KDC, &list);
332 if(ret != 0 || list == NULL)
333 return KRB5_PLUGIN_NO_HANDLE;
334
335 for (e = list; e != NULL; e = _krb5_plugin_get_next(e)) {
336 krb5plugin_send_to_kdc_ftable *service;
337 void *ctx;
338
339 service = _krb5_plugin_get_symbol(e);
340 if (service->minor_version != 0)
341 continue;
342
343 (*service->init)(context, &ctx);
344 ret = (*service->send_to_kdc)(context, ctx, hi,
345 timeout, send_data, receive);
346 (*service->fini)(ctx);
347 if (ret == 0)
348 break;
349 if (ret != KRB5_PLUGIN_NO_HANDLE) {
350 krb5_set_error_message(context, ret,
351 N_("Plugin send_to_kdc failed to "
352 "lookup with error: %d", ""), ret);
353 break;
354 }
355 }
356 _krb5_plugin_free(list);
357 return KRB5_PLUGIN_NO_HANDLE;
358 }
359
360
361 /*
362 * Send the data `send' to one host from `handle` and get back the reply
363 * in `receive'.
364 */
365
366 krb5_error_code KRB5_LIB_FUNCTION
367 krb5_sendto (krb5_context context,
/* [<][>][^][v][top][bottom][index][help] */
368 const krb5_data *send_data,
369 krb5_krbhst_handle handle,
370 krb5_data *receive)
371 {
372 krb5_error_code ret;
373 int fd;
374 int i;
375
376 krb5_data_zero(receive);
377
378 for (i = 0; i < context->max_retries; ++i) {
379 krb5_krbhst_info *hi;
380
381 while (krb5_krbhst_next(context, handle, &hi) == 0) {
382 struct addrinfo *ai, *a;
383
384 if (context->send_to_kdc) {
385 struct send_to_kdc *s = context->send_to_kdc;
386
387 ret = (*s->func)(context, s->data,
388 hi, context->kdc_timeout, send_data, receive);
389 if (ret == 0 && receive->length != 0)
390 goto out;
391 continue;
392 }
393
394 ret = send_via_plugin(context, hi, context->kdc_timeout,
395 send_data, receive);
396 if (ret == 0 && receive->length != 0)
397 goto out;
398 else if (ret != KRB5_PLUGIN_NO_HANDLE)
399 continue;
400
401 if(hi->proto == KRB5_KRBHST_HTTP && context->http_proxy) {
402 if (send_via_proxy (context, hi, send_data, receive) == 0) {
403 ret = 0;
404 goto out;
405 }
406 continue;
407 }
408
409 ret = krb5_krbhst_get_addrinfo(context, hi, &ai);
410 if (ret)
411 continue;
412
413 for (a = ai; a != NULL; a = a->ai_next) {
414 fd = socket (a->ai_family, a->ai_socktype | SOCK_CLOEXEC, a->ai_protocol);
415 if (fd < 0)
416 continue;
417 rk_cloexec(fd);
418 if (connect (fd, a->ai_addr, a->ai_addrlen) < 0) {
419 close (fd);
420 continue;
421 }
422 switch (hi->proto) {
423 case KRB5_KRBHST_HTTP :
424 ret = send_and_recv_http(fd, context->kdc_timeout,
425 "", send_data, receive);
426 break;
427 case KRB5_KRBHST_TCP :
428 ret = send_and_recv_tcp (fd, context->kdc_timeout,
429 send_data, receive);
430 break;
431 case KRB5_KRBHST_UDP :
432 ret = send_and_recv_udp (fd, context->kdc_timeout,
433 send_data, receive);
434 break;
435 }
436 close (fd);
437 if(ret == 0 && receive->length != 0)
438 goto out;
439 }
440 }
441 krb5_krbhst_reset(context, handle);
442 }
443 krb5_clear_error_message (context);
444 ret = KRB5_KDC_UNREACH;
445 out:
446 return ret;
447 }
448
449 krb5_error_code KRB5_LIB_FUNCTION
450 krb5_sendto_kdc(krb5_context context,
/* [<][>][^][v][top][bottom][index][help] */
451 const krb5_data *send_data,
452 const krb5_realm *realm,
453 krb5_data *receive)
454 {
455 return krb5_sendto_kdc_flags(context, send_data, realm, receive, 0);
456 }
457
458 krb5_error_code KRB5_LIB_FUNCTION
459 krb5_sendto_kdc_flags(krb5_context context,
/* [<][>][^][v][top][bottom][index][help] */
460 const krb5_data *send_data,
461 const krb5_realm *realm,
462 krb5_data *receive,
463 int flags)
464 {
465 krb5_error_code ret;
466 krb5_sendto_ctx ctx;
467
468 ret = krb5_sendto_ctx_alloc(context, &ctx);
469 if (ret)
470 return ret;
471 krb5_sendto_ctx_add_flags(ctx, flags);
472 krb5_sendto_ctx_set_func(ctx, _krb5_kdc_retry, NULL);
473
474 ret = krb5_sendto_context(context, ctx, send_data, *realm, receive);
475 krb5_sendto_ctx_free(context, ctx);
476 return ret;
477 }
478
479 krb5_error_code KRB5_LIB_FUNCTION
480 krb5_set_send_to_kdc_func(krb5_context context,
/* [<][>][^][v][top][bottom][index][help] */
481 krb5_send_to_kdc_func func,
482 void *data)
483 {
484 free(context->send_to_kdc);
485 if (func == NULL) {
486 context->send_to_kdc = NULL;
487 return 0;
488 }
489
490 context->send_to_kdc = malloc(sizeof(*context->send_to_kdc));
491 if (context->send_to_kdc == NULL) {
492 krb5_set_error_message(context, ENOMEM,
493 N_("malloc: out of memory", ""));
494 return ENOMEM;
495 }
496
497 context->send_to_kdc->func = func;
498 context->send_to_kdc->data = data;
499 return 0;
500 }
501
502 krb5_error_code KRB5_LIB_FUNCTION
503 _krb5_copy_send_to_kdc_func(krb5_context context, krb5_context to)
/* [<][>][^][v][top][bottom][index][help] */
504 {
505 if (context->send_to_kdc)
506 return krb5_set_send_to_kdc_func(to,
507 context->send_to_kdc->func,
508 context->send_to_kdc->data);
509 else
510 return krb5_set_send_to_kdc_func(to, NULL, NULL);
511 }
512
513
514
515 struct krb5_sendto_ctx_data {
516 int flags;
517 int type;
518 krb5_sendto_ctx_func func;
519 void *data;
520 };
521
522 krb5_error_code KRB5_LIB_FUNCTION
523 krb5_sendto_ctx_alloc(krb5_context context, krb5_sendto_ctx *ctx)
/* [<][>][^][v][top][bottom][index][help] */
524 {
525 *ctx = calloc(1, sizeof(**ctx));
526 if (*ctx == NULL) {
527 krb5_set_error_message(context, ENOMEM,
528 N_("malloc: out of memory", ""));
529 return ENOMEM;
530 }
531 return 0;
532 }
533
534 void KRB5_LIB_FUNCTION
535 krb5_sendto_ctx_add_flags(krb5_sendto_ctx ctx, int flags)
/* [<][>][^][v][top][bottom][index][help] */
536 {
537 ctx->flags |= flags;
538 }
539
540 int KRB5_LIB_FUNCTION
541 krb5_sendto_ctx_get_flags(krb5_sendto_ctx ctx)
/* [<][>][^][v][top][bottom][index][help] */
542 {
543 return ctx->flags;
544 }
545
546 void KRB5_LIB_FUNCTION
547 krb5_sendto_ctx_set_type(krb5_sendto_ctx ctx, int type)
/* [<][>][^][v][top][bottom][index][help] */
548 {
549 ctx->type = type;
550 }
551
552
553 void KRB5_LIB_FUNCTION
554 krb5_sendto_ctx_set_func(krb5_sendto_ctx ctx,
/* [<][>][^][v][top][bottom][index][help] */
555 krb5_sendto_ctx_func func,
556 void *data)
557 {
558 ctx->func = func;
559 ctx->data = data;
560 }
561
562 void KRB5_LIB_FUNCTION
563 krb5_sendto_ctx_free(krb5_context context, krb5_sendto_ctx ctx)
/* [<][>][^][v][top][bottom][index][help] */
564 {
565 memset(ctx, 0, sizeof(*ctx));
566 free(ctx);
567 }
568
569 krb5_error_code KRB5_LIB_FUNCTION
570 krb5_sendto_context(krb5_context context,
/* [<][>][^][v][top][bottom][index][help] */
571 krb5_sendto_ctx ctx,
572 const krb5_data *send_data,
573 const krb5_realm realm,
574 krb5_data *receive)
575 {
576 krb5_error_code ret;
577 krb5_krbhst_handle handle = NULL;
578 int type, freectx = 0;
579 int action;
580
581 krb5_data_zero(receive);
582
583 if (ctx == NULL) {
584 freectx = 1;
585 ret = krb5_sendto_ctx_alloc(context, &ctx);
586 if (ret)
587 return ret;
588 }
589
590 type = ctx->type;
591 if (type == 0) {
592 if ((ctx->flags & KRB5_KRBHST_FLAGS_MASTER) || context->use_admin_kdc)
593 type = KRB5_KRBHST_ADMIN;
594 else
595 type = KRB5_KRBHST_KDC;
596 }
597
598 if (send_data->length > context->large_msg_size)
599 ctx->flags |= KRB5_KRBHST_FLAGS_LARGE_MSG;
600
601 /* loop until we get back a appropriate response */
602
603 do {
604 action = KRB5_SENDTO_DONE;
605
606 krb5_data_free(receive);
607
608 if (handle == NULL) {
609 ret = krb5_krbhst_init_flags(context, realm, type,
610 ctx->flags, &handle);
611 if (ret) {
612 if (freectx)
613 krb5_sendto_ctx_free(context, ctx);
614 return ret;
615 }
616 }
617
618 ret = krb5_sendto(context, send_data, handle, receive);
619 if (ret)
620 break;
621 if (ctx->func) {
622 ret = (*ctx->func)(context, ctx, ctx->data, receive, &action);
623 if (ret)
624 break;
625 }
626 if (action != KRB5_SENDTO_CONTINUE) {
627 krb5_krbhst_free(context, handle);
628 handle = NULL;
629 }
630 } while (action != KRB5_SENDTO_DONE);
631 if (handle)
632 krb5_krbhst_free(context, handle);
633 if (ret == KRB5_KDC_UNREACH)
634 krb5_set_error_message(context, ret,
635 N_("unable to reach any KDC in realm %s", ""),
636 realm);
637 if (ret)
638 krb5_data_free(receive);
639 if (freectx)
640 krb5_sendto_ctx_free(context, ctx);
641 return ret;
642 }
643
644 krb5_error_code
645 _krb5_kdc_retry(krb5_context context, krb5_sendto_ctx ctx, void *data,
/* [<][>][^][v][top][bottom][index][help] */
646 const krb5_data *reply, int *action)
647 {
648 krb5_error_code ret;
649 KRB_ERROR error;
650
651 if(krb5_rd_error(context, reply, &error))
652 return 0;
653
654 ret = krb5_error_from_rd_error(context, &error, NULL);
655 krb5_free_error_contents(context, &error);
656
657 switch(ret) {
658 case KRB5KRB_ERR_RESPONSE_TOO_BIG: {
659 if (krb5_sendto_ctx_get_flags(ctx) & KRB5_KRBHST_FLAGS_LARGE_MSG)
660 break;
661 krb5_sendto_ctx_add_flags(ctx, KRB5_KRBHST_FLAGS_LARGE_MSG);
662 *action = KRB5_SENDTO_RESTART;
663 break;
664 }
665 case KRB5KDC_ERR_SVC_UNAVAILABLE:
666 *action = KRB5_SENDTO_CONTINUE;
667 break;
668 }
669 return 0;
670 }