client/cifs.upcall.c

   1 /*
   2 * CIFS user-space helper.
   3 * Copyright (C) Igor Mammedov (niallain@gmail.com) 2007
   4 * Copyright (C) Jeff Layton (jlayton@redhat.com) 2009
   5 *
   6 * Used by /sbin/request-key for handling
   7 * cifs upcall for kerberos authorization of access to share and
   8 * cifs upcall for DFS srver name resolving (IPv4/IPv6 aware).
   9 * You should have keyutils installed and add something like the
  10 * following lines to /etc/request-key.conf file:
  11
  12 create cifs.spnego * * /usr/local/sbin/cifs.upcall %k
  13 create dns_resolver * * /usr/local/sbin/cifs.upcall %k
  14
  15 * This program is free software; you can redistribute it and/or modify
  16 * it under the terms of the GNU General Public License as published by
  17 * the Free Software Foundation; either version 2 of the License, or
  18 * (at your option) any later version.
  19 * This program is distributed in the hope that it will be useful,
  20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  22 * GNU General Public License for more details.
  23 * You should have received a copy of the GNU General Public License
  24 * along with this program; if not, write to the Free Software
  25 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  26 */
  27
  28 #include "includes.h"
  29 #include "../libcli/auth/spnego.h"
  30 #include <keyutils.h>
  31 #include <getopt.h>
  32
  33 #include "cifs_spnego.h"
  34
  35 #define CIFS_DEFAULT_KRB5_DIR           "/tmp"
  36 #define CIFS_DEFAULT_KRB5_PREFIX        "krb5cc_"
  37
  38 #define MAX_CCNAME_LEN                  PATH_MAX + 5
  39
  40 const char *CIFSSPNEGO_VERSION = "1.3";
  41 static const char *prog = "cifs.upcall";
  42 typedef enum _sectype {
  43         NONE = 0,
  44         KRB5,
  45         MS_KRB5
  46 } sectype_t;
  47
  48 static inline int
  49 k5_data_equal(krb5_data d1, krb5_data d2, unsigned int length)
  50 {
  51         if (!length)
  52                 length = d1.length;
  53
  54         return (d1.length == length &&
  55                 d1.length == d2.length &&
  56                 memcmp(d1.data, d2.data, length) == 0);
  57
  58 }
  59
  60 /* does the ccache have a valid TGT? */
  61 static time_t
  62 get_tgt_time(const char *ccname) {
  63         krb5_context context;
  64         krb5_ccache ccache;
  65         krb5_cc_cursor cur;
  66         krb5_creds creds;
  67         krb5_principal principal;
  68         krb5_data tgt = { .data =       "krbtgt",
  69                           .length =     6 };
  70         time_t credtime = 0;
  71
  72         if (krb5_init_context(&context)) {
  73                 syslog(LOG_DEBUG, "%s: unable to init krb5 context", __func__);
  74                 return 0;
  75         }
  76
  77         if (krb5_cc_resolve(context, ccname, &ccache)) {
  78                 syslog(LOG_DEBUG, "%s: unable to resolve krb5 cache", __func__);
  79                 goto err_cache;
  80         }
  81
  82         if (krb5_cc_set_flags(context, ccache, 0)) {
  83                 syslog(LOG_DEBUG, "%s: unable to set flags", __func__);
  84                 goto err_cache;
  85         }
  86
  87         if (krb5_cc_get_principal(context, ccache, &principal)) {
  88                 syslog(LOG_DEBUG, "%s: unable to get principal", __func__);
  89                 goto err_princ;
  90         }
  91
  92         if (krb5_cc_start_seq_get(context, ccache, &cur)) {
  93                 syslog(LOG_DEBUG, "%s: unable to seq start", __func__);
  94                 goto err_ccstart;
  95         }
  96
  97         while (!credtime && !krb5_cc_next_cred(context, ccache, &cur, &creds)) {
  98                 if (k5_data_equal(creds.server->realm, principal->realm, 0) &&
  99                     k5_data_equal(creds.server->data[0], tgt, tgt.length) &&
 100                     k5_data_equal(creds.server->data[1], principal->realm, 0) &&
 101                     creds.times.endtime > time(NULL))
 102                         credtime = creds.times.endtime;
 103                 krb5_free_cred_contents(context, &creds);
 104         }
 105         krb5_cc_end_seq_get(context, ccache, &cur);
 106
 107 err_ccstart:
 108         krb5_free_principal(context, principal);
 109 err_princ:
 110         krb5_cc_set_flags(context, ccache, KRB5_TC_OPENCLOSE);
 111         krb5_cc_close(context, ccache);
 112 err_cache:
 113         krb5_free_context(context);
 114         return credtime;
 115 }
 116
 117 static int
 118 krb5cc_filter(const struct dirent *dirent)
 119 {
 120         if (strstr(dirent->d_name, CIFS_DEFAULT_KRB5_PREFIX))
 121                 return 1;
 122         else
 123                 return 0;
 124 }
 125
 126 /* search for a credcache that looks like a likely candidate */
 127 static char *
 128 find_krb5_cc(const char *dirname, uid_t uid)
 129 {
 130         struct dirent **namelist;
 131         struct stat sbuf;
 132         char ccname[MAX_CCNAME_LEN], *credpath, *best_cache = NULL;
 133         int i, n;
 134         time_t cred_time, best_time = 0;
 135
 136         n = scandir(dirname, &namelist, krb5cc_filter, NULL);
 137         if (n < 0) {
 138                 syslog(LOG_DEBUG, "%s: scandir error on directory '%s': %s",
 139                                   __func__, dirname, strerror(errno));
 140                 return NULL;
 141         }
 142
 143         for (i = 0; i < n; i++) {
 144                 snprintf(ccname, sizeof(ccname), "FILE:%s/%s", dirname,
 145                          namelist[i]->d_name);
 146                 credpath = ccname + 5;
 147                 syslog(LOG_DEBUG, "%s: considering %s", __func__, credpath);
 148
 149                 if (lstat(credpath, &sbuf)) {
 150                         syslog(LOG_DEBUG, "%s: stat error on '%s': %s",
 151                                           __func__, credpath, strerror(errno));
 152                         free(namelist[i]);
 153                         continue;
 154                 }
 155                 if (sbuf.st_uid != uid) {
 156                         syslog(LOG_DEBUG, "%s: %s is owned by %u, not %u",
 157                                         __func__, credpath, sbuf.st_uid, uid);
 158                         free(namelist[i]);
 159                         continue;
 160                 }
 161                 if (!S_ISREG(sbuf.st_mode)) {
 162                         syslog(LOG_DEBUG, "%s: %s is not a regular file",
 163                                         __func__, credpath);
 164                         free(namelist[i]);
 165                         continue;
 166                 }
 167                 if (!(cred_time = get_tgt_time(ccname))) {
 168                         syslog(LOG_DEBUG, "%s: %s is not a valid credcache.",
 169                                         __func__, ccname);
 170                         free(namelist[i]);
 171                         continue;
 172                 }
 173
 174                 if (cred_time <= best_time) {
 175                         syslog(LOG_DEBUG, "%s: %s expires sooner than current "
 176                                           "best.", __func__, ccname);
 177                         free(namelist[i]);
 178                         continue;
 179                 }
 180
 181                 syslog(LOG_DEBUG, "%s: %s is valid ccache", __func__, ccname);
 182                 free(best_cache);
 183                 best_cache = SMB_STRNDUP(ccname, MAX_CCNAME_LEN);
 184                 best_time = cred_time;
 185                 free(namelist[i]);
 186         }
 187         free(namelist);
 188
 189         return best_cache;
 190 }
 191
 192 /*
 193  * Prepares AP-REQ data for mechToken and gets session key
 194  * Uses credentials from cache. It will not ask for password
 195  * you should receive credentials for yuor name manually using
 196  * kinit or whatever you wish.
 197  *
 198  * in:
 199  *      oid -           string with OID/ Could be OID_KERBEROS5
 200  *                      or OID_KERBEROS5_OLD
 201  *      principal -     Service name.
 202  *                      Could be "cifs/FQDN" for KRB5 OID
 203  *                      or for MS_KRB5 OID style server principal
 204  *                      like "pdc$@YOUR.REALM.NAME"
 205  *
 206  * out:
 207  *      secblob -       pointer for spnego wrapped AP-REQ data to be stored
 208  *      sess_key-       pointer for SessionKey data to be stored
 209  *
 210  * ret: 0 - success, others - failure
 211  */
 212 static int
 213 handle_krb5_mech(const char *oid, const char *principal, DATA_BLOB *secblob,
 214                  DATA_BLOB *sess_key, const char *ccname)
 215 {
 216         int retval;
 217         DATA_BLOB tkt, tkt_wrapped;
 218
 219         syslog(LOG_DEBUG, "%s: getting service ticket for %s", __func__,
 220                           principal);
 221
 222         /* get a kerberos ticket for the service and extract the session key */
 223         retval = cli_krb5_get_ticket(principal, 0, &tkt, sess_key, 0, ccname,
 224                                      NULL);
 225
 226         if (retval) {
 227                 syslog(LOG_DEBUG, "%s: failed to obtain service ticket (%d)",
 228                                   __func__, retval);
 229                 return retval;
 230         }
 231
 232         syslog(LOG_DEBUG, "%s: obtained service ticket", __func__);
 233
 234         /* wrap that up in a nice GSS-API wrapping */
 235         tkt_wrapped = spnego_gen_krb5_wrap(tkt, TOK_ID_KRB_AP_REQ);
 236
 237         /* and wrap that in a shiny SPNEGO wrapper */
 238         *secblob = gen_negTokenInit(oid, tkt_wrapped);
 239
 240         data_blob_free(&tkt_wrapped);
 241         data_blob_free(&tkt);
 242         return retval;
 243 }
 244
 245 #define DKD_HAVE_HOSTNAME       0x1
 246 #define DKD_HAVE_VERSION        0x2
 247 #define DKD_HAVE_SEC            0x4
 248 #define DKD_HAVE_IP             0x8
 249 #define DKD_HAVE_UID            0x10
 250 #define DKD_HAVE_PID            0x20
 251 #define DKD_MUSTHAVE_SET (DKD_HAVE_HOSTNAME|DKD_HAVE_VERSION|DKD_HAVE_SEC)
 252
 253 struct decoded_args {
 254         int             ver;
 255         char            *hostname;
 256         char            *ip;
 257         uid_t           uid;
 258         pid_t           pid;
 259         sectype_t       sec;
 260 };
 261
 262 static unsigned int
 263 decode_key_description(const char *desc, struct decoded_args *arg)
 264 {
 265         int len;
 266         int retval = 0;
 267         char *pos;
 268         const char *tkn = desc;
 269
 270         do {
 271                 pos = index(tkn, ';');
 272                 if (strncmp(tkn, "host=", 5) == 0) {
 273
 274                         if (pos == NULL)
 275                                 len = strlen(tkn);
 276                         else
 277                                 len = pos - tkn;
 278
 279                         len -= 4;
 280                         SAFE_FREE(arg->hostname);
 281                         arg->hostname = SMB_XMALLOC_ARRAY(char, len);
 282                         strlcpy(arg->hostname, tkn + 5, len);
 283                         retval |= DKD_HAVE_HOSTNAME;
 284                 } else if (!strncmp(tkn, "ip4=", 4) ||
 285                            !strncmp(tkn, "ip6=", 4)) {
 286                         if (pos == NULL)
 287                                 len = strlen(tkn);
 288                         else
 289                                 len = pos - tkn;
 290
 291                         len -= 3;
 292                         SAFE_FREE(arg->ip);
 293                         arg->ip = SMB_XMALLOC_ARRAY(char, len);
 294                         strlcpy(arg->ip, tkn + 4, len);
 295                         retval |= DKD_HAVE_IP;
 296                 } else if (strncmp(tkn, "pid=", 4) == 0) {
 297                         errno = 0;
 298                         arg->pid = strtol(tkn + 4, NULL, 0);
 299                         if (errno != 0) {
 300                                 syslog(LOG_ERR, "Invalid pid format: %s",
 301                                        strerror(errno));
 302                                 return 1;
 303                         } else {
 304                                 retval |= DKD_HAVE_PID;
 305                         }
 306                 } else if (strncmp(tkn, "sec=", 4) == 0) {
 307                         if (strncmp(tkn + 4, "krb5", 4) == 0) {
 308                                 retval |= DKD_HAVE_SEC;
 309                                 arg->sec = KRB5;
 310                         } else if (strncmp(tkn + 4, "mskrb5", 6) == 0) {
 311                                 retval |= DKD_HAVE_SEC;
 312                                 arg->sec = MS_KRB5;
 313                         }
 314                 } else if (strncmp(tkn, "uid=", 4) == 0) {
 315                         errno = 0;
 316                         arg->uid = strtol(tkn + 4, NULL, 16);
 317                         if (errno != 0) {
 318                                 syslog(LOG_ERR, "Invalid uid format: %s",
 319                                        strerror(errno));
 320                                 return 1;
 321                         } else {
 322                                 retval |= DKD_HAVE_UID;
 323                         }
 324                 } else if (strncmp(tkn, "ver=", 4) == 0) {      /* if version */
 325                         errno = 0;
 326                         arg->ver = strtol(tkn + 4, NULL, 16);
 327                         if (errno != 0) {
 328                                 syslog(LOG_ERR, "Invalid version format: %s",
 329                                        strerror(errno));
 330                                 return 1;
 331                         } else {
 332                                 retval |= DKD_HAVE_VERSION;
 333                         }
 334                 }
 335                 if (pos == NULL)
 336                         break;
 337                 tkn = pos + 1;
 338         } while (tkn);
 339         return retval;
 340 }
 341
 342 static int
 343 cifs_resolver(const key_serial_t key, const char *key_descr)
 344 {
 345         int c;
 346         struct addrinfo *addr;
 347         char ip[INET6_ADDRSTRLEN];
 348         void *p;
 349         const char *keyend = key_descr;
 350         /* skip next 4 ';' delimiters to get to description */
 351         for (c = 1; c <= 4; c++) {
 352                 keyend = index(keyend+1, ';');
 353                 if (!keyend) {
 354                         syslog(LOG_ERR, "invalid key description: %s",
 355                                         key_descr);
 356                         return 1;
 357                 }
 358         }
 359         keyend++;
 360
 361         /* resolve name to ip */
 362         c = getaddrinfo(keyend, NULL, NULL, &addr);
 363         if (c) {
 364                 syslog(LOG_ERR, "unable to resolve hostname: %s [%s]",
 365                                 keyend, gai_strerror(c));
 366                 return 1;
 367         }
 368
 369         /* conver ip to string form */
 370         if (addr->ai_family == AF_INET)
 371                 p = &(((struct sockaddr_in *)addr->ai_addr)->sin_addr);
 372         else
 373                 p = &(((struct sockaddr_in6 *)addr->ai_addr)->sin6_addr);
 374
 375         if (!inet_ntop(addr->ai_family, p, ip, sizeof(ip))) {
 376                 syslog(LOG_ERR, "%s: inet_ntop: %s", __func__, strerror(errno));
 377                 freeaddrinfo(addr);
 378                 return 1;
 379         }
 380
 381         /* setup key */
 382         c = keyctl_instantiate(key, ip, strlen(ip)+1, 0);
 383         if (c == -1) {
 384                 syslog(LOG_ERR, "%s: keyctl_instantiate: %s", __func__,
 385                                 strerror(errno));
 386                 freeaddrinfo(addr);
 387                 return 1;
 388         }
 389
 390         freeaddrinfo(addr);
 391         return 0;
 392 }
 393
 394 /*
 395  * Older kernels sent IPv6 addresses without colons. Well, at least
 396  * they're fixed-length strings. Convert these addresses to have colon
 397  * delimiters to make getaddrinfo happy.
 398  */
 399 static void
 400 convert_inet6_addr(const char *from, char *to)
 401 {
 402         int i = 1;
 403
 404         while (*from) {
 405                 *to++ = *from++;
 406                 if (!(i++ % 4) && *from)
 407                         *to++ = ':';
 408         }
 409         *to = 0;
 410 }
 411
 412 static int
 413 ip_to_fqdn(const char *addrstr, char *host, size_t hostlen)
 414 {
 415         int rc;
 416         struct addrinfo hints = { .ai_flags = AI_NUMERICHOST };
 417         struct addrinfo *res;
 418         const char *ipaddr = addrstr;
 419         char converted[INET6_ADDRSTRLEN + 1];
 420
 421         if ((strlen(ipaddr) > INET_ADDRSTRLEN) && !strchr(ipaddr, ':')) {
 422                 convert_inet6_addr(ipaddr, converted);
 423                 ipaddr = converted;
 424         }
 425
 426         rc = getaddrinfo(ipaddr, NULL, &hints, &res);
 427         if (rc) {
 428                 syslog(LOG_DEBUG, "%s: failed to resolve %s to "
 429                         "ipaddr: %s", __func__, ipaddr,
 430                 rc == EAI_SYSTEM ? strerror(errno) : gai_strerror(rc));
 431                 return rc;
 432         }
 433
 434         rc = getnameinfo(res->ai_addr, res->ai_addrlen, host, hostlen,
 435                          NULL, 0, NI_NAMEREQD);
 436         freeaddrinfo(res);
 437         if (rc) {
 438                 syslog(LOG_DEBUG, "%s: failed to resolve %s to fqdn: %s",
 439                         __func__, ipaddr,
 440                         rc == EAI_SYSTEM ? strerror(errno) : gai_strerror(rc));
 441                 return rc;
 442         }
 443
 444         syslog(LOG_DEBUG, "%s: resolved %s to %s", __func__, ipaddr, host);
 445         return 0;
 446 }
 447
 448 static void
 449 usage(void)
 450 {
 451         syslog(LOG_INFO, "Usage: %s [-t] [-v] key_serial", prog);
 452         fprintf(stderr, "Usage: %s [-t] [-v] key_serial\n", prog);
 453 }
 454
 455 const struct option long_options[] = {
 456         { "trust-dns",  0, NULL, 't' },
 457         { "version",    0, NULL, 'v' },
 458         { NULL,         0, NULL, 0 }
 459 };
 460
 461 int main(const int argc, char *const argv[])
 462 {
 463         struct cifs_spnego_msg *keydata = NULL;
 464         DATA_BLOB secblob = data_blob_null;
 465         DATA_BLOB sess_key = data_blob_null;
 466         key_serial_t key = 0;
 467         size_t datalen;
 468         unsigned int have;
 469         long rc = 1;
 470         int c, try_dns = 0;
 471         char *buf, *princ = NULL, *ccname = NULL;
 472         char hostbuf[NI_MAXHOST], *host;
 473         struct decoded_args arg = { };
 474         const char *oid;
 475
 476         hostbuf[0] = '\0';
 477
 478         openlog(prog, 0, LOG_DAEMON);
 479
 480         while ((c = getopt_long(argc, argv, "ctv", long_options, NULL)) != -1) {
 481                 switch (c) {
 482                 case 'c':
 483                         /* legacy option -- skip it */
 484                         break;
 485                 case 't':
 486                         try_dns++;
 487                         break;
 488                 case 'v':
 489                         printf("version: %s\n", CIFSSPNEGO_VERSION);
 490                         goto out;
 491                 default:
 492                         syslog(LOG_ERR, "unknown option: %c", c);
 493                         goto out;
 494                 }
 495         }
 496
 497         /* is there a key? */
 498         if (argc <= optind) {
 499                 usage();
 500                 goto out;
 501         }
 502
 503         /* get key and keyring values */
 504         errno = 0;
 505         key = strtol(argv[optind], NULL, 10);
 506         if (errno != 0) {
 507                 key = 0;
 508                 syslog(LOG_ERR, "Invalid key format: %s", strerror(errno));
 509                 goto out;
 510         }
 511
 512         rc = keyctl_describe_alloc(key, &buf);
 513         if (rc == -1) {
 514                 syslog(LOG_ERR, "keyctl_describe_alloc failed: %s",
 515                        strerror(errno));
 516                 rc = 1;
 517                 goto out;
 518         }
 519
 520         syslog(LOG_DEBUG, "key description: %s", buf);
 521
 522         if ((strncmp(buf, "cifs.resolver", sizeof("cifs.resolver")-1) == 0) ||
 523             (strncmp(buf, "dns_resolver", sizeof("dns_resolver")-1) == 0)) {
 524                 rc = cifs_resolver(key, buf);
 525                 goto out;
 526         }
 527
 528         have = decode_key_description(buf, &arg);
 529         SAFE_FREE(buf);
 530         if ((have & DKD_MUSTHAVE_SET) != DKD_MUSTHAVE_SET) {
 531                 syslog(LOG_ERR, "unable to get necessary params from key "
 532                                 "description (0x%x)", have);
 533                 rc = 1;
 534                 goto out;
 535         }
 536
 537         if (arg.ver > CIFS_SPNEGO_UPCALL_VERSION) {
 538                 syslog(LOG_ERR, "incompatible kernel upcall version: 0x%x",
 539                                 arg.ver);
 540                 rc = 1;
 541                 goto out;
 542         }
 543
 544         if (have & DKD_HAVE_UID) {
 545                 rc = setuid(arg.uid);
 546                 if (rc == -1) {
 547                         syslog(LOG_ERR, "setuid: %s", strerror(errno));
 548                         goto out;
 549                 }
 550
 551                 ccname = find_krb5_cc(CIFS_DEFAULT_KRB5_DIR, arg.uid);
 552         }
 553
 554         host = arg.hostname;
 555
 556         // do mech specific authorization
 557         switch (arg.sec) {
 558         case MS_KRB5:
 559         case KRB5:
 560 retry_new_hostname:
 561                 /* for "cifs/" service name + terminating 0 */
 562                 datalen = strlen(host) + 5 + 1;
 563                 princ = SMB_XMALLOC_ARRAY(char, datalen);
 564                 if (!princ) {
 565                         rc = -ENOMEM;
 566                         break;
 567                 }
 568
 569                 if (arg.sec == MS_KRB5)
 570                         oid = OID_KERBEROS5_OLD;
 571                 else
 572                         oid = OID_KERBEROS5;
 573
 574                 /*
 575                  * try getting a cifs/ principal first and then fall back to
 576                  * getting a host/ principal if that doesn't work.
 577                  */
 578                 strlcpy(princ, "cifs/", datalen);
 579                 strlcpy(princ + 5, host, datalen - 5);
 580                 rc = handle_krb5_mech(oid, princ, &secblob, &sess_key, ccname);
 581                 if (!rc)
 582                         break;
 583
 584                 memcpy(princ, "host/", 5);
 585                 rc = handle_krb5_mech(oid, princ, &secblob, &sess_key, ccname);
 586                 if (!rc)
 587                         break;
 588
 589                 if (!try_dns || !(have & DKD_HAVE_IP))
 590                         break;
 591
 592                 rc = ip_to_fqdn(arg.ip, hostbuf, sizeof(hostbuf));
 593                 if (rc)
 594                         break;
 595
 596                 SAFE_FREE(princ);
 597                 try_dns = 0;
 598                 host = hostbuf;
 599                 goto retry_new_hostname;
 600         default:
 601                 syslog(LOG_ERR, "sectype: %d is not implemented", arg.sec);
 602                 rc = 1;
 603                 break;
 604         }
 605
 606         SAFE_FREE(princ);
 607
 608         if (rc)
 609                 goto out;
 610
 611         /* pack SecurityBLob and SessionKey into downcall packet */
 612         datalen =
 613             sizeof(struct cifs_spnego_msg) + secblob.length + sess_key.length;
 614         keydata = (struct cifs_spnego_msg*)SMB_XMALLOC_ARRAY(char, datalen);
 615         if (!keydata) {
 616                 rc = 1;
 617                 goto out;
 618         }
 619         keydata->version = arg.ver;
 620         keydata->flags = 0;
 621         keydata->sesskey_len = sess_key.length;
 622         keydata->secblob_len = secblob.length;
 623         memcpy(&(keydata->data), sess_key.data, sess_key.length);
 624         memcpy(&(keydata->data) + keydata->sesskey_len,
 625                secblob.data, secblob.length);
 626
 627         /* setup key */
 628         rc = keyctl_instantiate(key, keydata, datalen, 0);
 629         if (rc == -1) {
 630                 syslog(LOG_ERR, "keyctl_instantiate: %s", strerror(errno));
 631                 goto out;
 632         }
 633
 634         /* BB: maybe we need use timeout for key: for example no more then
 635          * ticket lifietime? */
 636         /* keyctl_set_timeout( key, 60); */
 637 out:
 638         /*
 639          * on error, negatively instantiate the key ourselves so that we can
 640          * make sure the kernel doesn't hang it off of a searchable keyring
 641          * and interfere with the next attempt to instantiate the key.
 642          */
 643         if (rc != 0  && key == 0)
 644                 keyctl_negate(key, 1, KEY_REQKEY_DEFL_DEFAULT);
 645         data_blob_free(&secblob);
 646         data_blob_free(&sess_key);
 647         SAFE_FREE(ccname);
 648         SAFE_FREE(arg.hostname);
 649         SAFE_FREE(arg.ip);
 650         SAFE_FREE(keydata);
 651         return rc;
 652 }