2 * Copyright 2000, International Business Machines Corporation and others.
5 * This software has been released under the terms of the IBM Public
6 * License. For details, see the LICENSE file in the top-level source
7 * directory or online at http://www.openafs.org/dl/license10.html
10 /* The rxkad security object. Authentication using a DES-encrypted
11 * Kerberos-style ticket. These are the server-only routines. */
14 #include <afsconfig.h>
15 #include <afs/param.h>
20 #if (defined(AFS_AIX_ENV) && defined(KERNEL) && !defined(UKERNEL)) || defined(AFS_AUX_ENV) || defined(AFS_SUN5_ENV)
21 #include <sys/systm.h>
27 #include <rx/rx_packet.h>
28 #include <afs/afsutil.h>
31 #include "private_data.h"
32 #define XPRT_RXKAD_SERVER
35 * This can be set to allow alternate ticket decoding.
36 * Currently only used by the AFS/DFS protocol translator to recognize
37 * Kerberos V5 tickets. The actual code to do that is provided externally.
39 afs_int32(*rxkad_AlternateTicketDecoder) (afs_int32, char *, afs_int32,
40 char *, char *, char *,
41 struct ktc_encryptionKey *,
42 afs_int32 *, afs_uint32 *,
45 static struct rx_securityOps rxkad_server_ops = {
48 rxkad_PreparePacket, /* once per packet creation */
49 0, /* send packet (once per retrans) */
50 rxkad_CheckAuthentication,
51 rxkad_CreateChallenge,
55 rxkad_CheckPacket, /* check data packet */
56 rxkad_DestroyConnection,
58 rxkad_SetConfiguration,
62 extern afs_uint32 rx_MyMaxSendSize;
64 /* Miscellaneous random number routines that use the fcrypt module and the
67 static fc_KeySchedule random_int32_schedule;
69 #ifdef AFS_PTHREAD_ENV
71 * This mutex protects the following global variables:
72 * random_int32_schedule
76 pthread_mutex_t rxkad_random_mutex
77 #ifdef PTHREAD_MUTEX_INITIALIZER
78 = PTHREAD_MUTEX_INITIALIZER
81 #define LOCK_RM opr_Verify(pthread_mutex_lock(&rxkad_random_mutex)==0)
82 #define UNLOCK_RM opr_Verify(pthread_mutex_unlock(&rxkad_random_mutex)==0)
86 #endif /* AFS_PTHREAD_ENV */
89 init_random_int32(void)
93 gettimeofday(&key, NULL);
95 fc_keysched((struct ktc_encryptionKey*)&key, random_int32_schedule);
100 get_random_int32(void)
102 static struct timeval seed;
106 fc_ecb_encrypt(&seed, &seed, random_int32_schedule, ENCRYPT);
112 /* Called with four parameters. The first is the level of encryption, as
113 defined in the rxkad.h file. The second and third are a rock and a
114 procedure that is called with the key version number that accompanies the
115 ticket and returns a pointer to the server's decryption key. The fourth
116 argument, if not NULL, is a pointer to a function that will be called for
117 every new connection with the name, instance and cell of the client. The
118 routine should return zero if the user is NOT acceptible to the server. If
119 this routine is not supplied, the server can call rxkad_GetServerInfo with
120 the rx connection pointer passed to the RPC routine to obtain information
124 rxkad_level level; * minimum level *
125 char *get_key_rock; * rock for get_key implementor *
126 int (*get_key)(); * passed kvno & addr(key) to fill *
127 int (*user_ok)(); * passed name, inst, cell => bool *
130 struct rx_securityClass *
131 rxkad_NewServerSecurityObject(rxkad_level level, void *get_key_rock,
132 int (*get_key) (void *get_key_rock, int kvno,
133 struct ktc_encryptionKey *
135 int (*user_ok) (char *name, char *instance,
136 char *cell, afs_int32 kvno))
138 struct rx_securityClass *tsc;
139 struct rxkad_sprivate *tsp;
147 size = sizeof(struct rx_securityClass);
148 tsc = osi_Alloc(size);
149 memset(tsc, 0, size);
150 tsc->refCount = 1; /* caller has one reference */
151 tsc->ops = &rxkad_server_ops;
152 size = sizeof(struct rxkad_sprivate);
153 tsp = osi_Alloc(size);
154 memset(tsp, 0, size);
155 tsc->privateData = (char *)tsp;
157 tsp->type |= rxkad_server; /* so can identify later */
158 tsp->level = level; /* level of encryption */
159 tsp->get_key_rock = get_key_rock;
160 tsp->get_key = get_key; /* to get server ticket */
161 tsp->user_ok = user_ok; /* to inform server of client id. */
164 INC_RXKAD_STATS(serverObjects);
168 /* server: called to tell if a connection authenticated properly */
171 rxkad_CheckAuthentication(struct rx_securityClass *aobj,
172 struct rx_connection *aconn)
174 struct rxkad_sconn *sconn = rx_GetSecurityData(aconn);
176 /* first make sure the object exists */
178 return RXKADINCONSISTENCY;
180 return !sconn->authenticated;
183 /* server: put the current challenge in the connection structure for later use
187 rxkad_CreateChallenge(struct rx_securityClass *aobj,
188 struct rx_connection *aconn)
190 struct rxkad_sconn *sconn = rx_GetSecurityData(aconn);
191 struct rxkad_sprivate *tsp;
193 sconn->challengeID = get_random_int32();
194 sconn->authenticated = 0; /* conn unauth. 'til we hear back */
195 /* initialize level from object's minimum acceptable level */
196 tsp = (struct rxkad_sprivate *)aobj->privateData;
197 sconn->level = tsp->level;
201 /* server: fill in a challenge in the packet */
204 rxkad_GetChallenge(struct rx_securityClass *aobj, struct rx_connection *aconn,
205 struct rx_packet *apacket)
207 struct rxkad_sconn *sconn = rx_GetSecurityData(aconn);
210 struct rxkad_v2Challenge c_v2; /* version 2 */
211 struct rxkad_oldChallenge c_old; /* old style */
213 if (rx_IsUsingPktCksum(aconn))
214 sconn->cksumSeen = 1;
216 if (sconn->cksumSeen) {
217 memset(&c_v2, 0, sizeof(c_v2));
218 c_v2.version = htonl(RXKAD_CHALLENGE_PROTOCOL_VERSION);
219 c_v2.challengeID = htonl(sconn->challengeID);
220 c_v2.level = htonl((afs_int32) sconn->level);
222 challenge = (char *)&c_v2;
223 challengeSize = sizeof(c_v2);
225 memset(&c_old, 0, sizeof(c_old));
226 c_old.challengeID = htonl(sconn->challengeID);
227 c_old.level = htonl((afs_int32) sconn->level);
228 challenge = (char *)&c_old;
229 challengeSize = sizeof(c_old);
231 if (rx_MyMaxSendSize < challengeSize)
232 return RXKADPACKETSHORT; /* not enough space */
234 rx_packetwrite(apacket, 0, challengeSize, challenge);
235 rx_SetDataSize(apacket, challengeSize);
237 INC_RXKAD_STATS(challengesSent);
241 /* server: process a response to a challenge packet */
242 /* XXX this does some copying of data in and out of the packet, but I'll bet it
243 * could just do it in place, especially if I used rx_Pullup...
246 rxkad_CheckResponse(struct rx_securityClass *aobj,
247 struct rx_connection *aconn, struct rx_packet *apacket)
249 struct rxkad_sconn *sconn;
250 struct rxkad_sprivate *tsp;
251 struct ktc_encryptionKey serverKey;
252 struct rxkad_oldChallengeResponse oldr; /* response format */
253 struct rxkad_v2ChallengeResponse v2r;
254 afs_int32 tlen; /* ticket len */
255 afs_int32 kvno; /* key version of ticket */
256 char tix[MAXKTCTICKETLEN];
257 afs_int32 incChallengeID;
260 /* ticket contents */
261 struct ktc_principal client;
262 struct ktc_encryptionKey sessionkey;
267 struct rxkad_serverinfo *rock;
269 sconn = rx_GetSecurityData(aconn);
270 tsp = (struct rxkad_sprivate *)aobj->privateData;
272 if (sconn->cksumSeen) {
273 /* expect v2 response, leave fields in v2r in network order for cksum
274 * computation which follows decryption. */
275 if (rx_GetDataSize(apacket) < sizeof(v2r))
276 return RXKADPACKETSHORT;
277 rx_packetread(apacket, 0, sizeof(v2r), &v2r);
281 kvno = ntohl(v2r.kvno);
282 tlen = ntohl(v2r.ticketLen);
283 if (rx_GetDataSize(apacket) < sizeof(v2r) + tlen)
284 return RXKADPACKETSHORT;
286 /* expect old format response */
287 if (rx_GetDataSize(apacket) < sizeof(oldr))
288 return RXKADPACKETSHORT;
289 rx_packetread(apacket, 0, sizeof(oldr), &oldr);
292 kvno = ntohl(oldr.kvno);
293 tlen = ntohl(oldr.ticketLen);
294 if (rx_GetDataSize(apacket) != sizeof(oldr) + tlen)
295 return RXKADPACKETSHORT;
297 if ((tlen < MINKTCTICKETLEN) || (tlen > MAXKTCTICKETLEN))
298 return RXKADTICKETLEN;
300 rx_packetread(apacket, pos, tlen, tix); /* get ticket */
303 * We allow the ticket to be optionally decoded by an alternate
304 * ticket decoder, if the function variable
305 * rxkad_AlternateTicketDecoder is set. That function should
306 * return a code of -1 if it wants the ticket to be decoded by
307 * the standard decoder.
309 if (rxkad_AlternateTicketDecoder) {
311 rxkad_AlternateTicketDecoder(kvno, tix, tlen, client.name,
312 client.instance, client.cell,
313 &sessionkey, &host, &start, &end);
314 if (code && code != -1) {
318 code = -1; /* No alternate ticket decoder present */
322 * If the alternate decoder is not present, or returns -1, then
323 * assume the ticket is of the default style.
325 if (code == -1 && ((kvno == RXKAD_TKT_TYPE_KERBEROS_V5)
326 || (kvno == RXKAD_TKT_TYPE_KERBEROS_V5_ENCPART_ONLY))) {
328 tkt_DecodeTicket5(tix, tlen, tsp->get_key, tsp->get_key_rock,
329 kvno, client.name, client.instance, client.cell,
330 &sessionkey, &host, &start, &end,
331 tsp->flags & RXS_CONFIG_FLAGS_DISABLE_DOTCHECK);
337 * If the alternate decoder/kerberos 5 decoder is not present, or
338 * returns -1, then assume the ticket is of the default style.
341 /* get ticket's key */
342 code = (*tsp->get_key) (tsp->get_key_rock, kvno, &serverKey);
344 return RXKADUNKNOWNKEY; /* invalid kvno */
346 tkt_DecodeTicket(tix, tlen, &serverKey, client.name,
347 client.instance, client.cell, &sessionkey, &host,
352 code = tkt_CheckTimes(start, end, time(0));
358 return RXKADBADTICKET;
360 code = fc_keysched(&sessionkey, sconn->keysched);
363 memcpy(sconn->ivec, &sessionkey, sizeof(sconn->ivec));
365 if (sconn->cksumSeen) {
366 /* using v2 response */
367 afs_uint32 cksum; /* observed cksum */
368 struct rxkad_endpoint endpoint; /* connections endpoint */
372 memcpy(xor, sconn->ivec, 2 * sizeof(afs_int32));
373 fc_cbc_encrypt(&v2r.encrypted, &v2r.encrypted, sizeof(v2r.encrypted),
374 sconn->keysched, xor, DECRYPT);
375 cksum = rxkad_CksumChallengeResponse(&v2r);
376 if (cksum != v2r.encrypted.endpoint.cksum)
377 return RXKADSEALEDINCON;
378 (void)rxkad_SetupEndpoint(aconn, &endpoint);
379 v2r.encrypted.endpoint.cksum = 0;
380 if (memcmp(&endpoint, &v2r.encrypted.endpoint, sizeof(endpoint)) != 0)
381 return RXKADSEALEDINCON;
382 for (i = 0; i < RX_MAXCALLS; i++) {
383 v2r.encrypted.callNumbers[i] =
384 ntohl(v2r.encrypted.callNumbers[i]);
385 if (v2r.encrypted.callNumbers[i] < 0)
386 return RXKADSEALEDINCON;
389 (void)rxi_SetCallNumberVector(aconn, v2r.encrypted.callNumbers);
390 incChallengeID = ntohl(v2r.encrypted.incChallengeID);
391 level = ntohl(v2r.encrypted.level);
393 /* expect old format response */
394 fc_ecb_encrypt(&oldr.encrypted, &oldr.encrypted, sconn->keysched,
396 incChallengeID = ntohl(oldr.encrypted.incChallengeID);
397 level = ntohl(oldr.encrypted.level);
399 if (incChallengeID != sconn->challengeID + 1)
400 return RXKADOUTOFSEQUENCE; /* replay attempt */
401 if ((level < sconn->level) || (level > rxkad_crypt))
402 return RXKADLEVELFAIL;
403 sconn->level = level;
404 rxkad_SetLevel(aconn, sconn->level);
405 INC_RXKAD_STATS(responses[rxkad_LevelIndex(sconn->level)]);
406 /* now compute endpoint-specific info used for computing 16 bit checksum */
407 rxkad_DeriveXORInfo(aconn, &sconn->keysched, (char *)sconn->ivec, (char *)sconn->preSeq);
409 /* otherwise things are ok */
410 sconn->expirationTime = end;
411 sconn->authenticated = 1;
414 code = tsp->user_ok(client.name, client.instance, client.cell, kvno);
417 } else { /* save the info for later retreival */
418 int size = sizeof(struct rxkad_serverinfo);
419 rock = osi_Alloc(size);
420 memset(rock, 0, size);
422 memcpy(&rock->client, &client, sizeof(rock->client));
428 /* return useful authentication info about a server-side connection */
431 rxkad_GetServerInfo(struct rx_connection * aconn, rxkad_level * level,
432 afs_uint32 * expiration, char *name, char *instance,
433 char *cell, afs_int32 * kvno)
435 struct rxkad_sconn *sconn;
437 sconn = rx_GetSecurityData(aconn);
438 if (sconn && sconn->authenticated && sconn->rock
439 && (time(0) < sconn->expirationTime)) {
441 *level = sconn->level;
443 *expiration = sconn->expirationTime;
445 strcpy(name, sconn->rock->client.name);
447 strcpy(instance, sconn->rock->client.instance);
449 strcpy(cell, sconn->rock->client.cell);
451 *kvno = sconn->rock->kvno;
457 /* Set security object configuration variables */
458 afs_int32 rxkad_SetConfiguration(struct rx_securityClass *aobj,
459 struct rx_connection *aconn,
460 rx_securityConfigVariables atype,
461 void * avalue, void **currentValue)
463 struct rxkad_sprivate *private =
464 (struct rxkad_sprivate *) aobj->privateData;
467 case RXS_CONFIG_FLAGS:
469 *((afs_uint32 *)currentValue) = private->flags;
471 private->flags = (intptr_t)avalue;