lustre/utils/gss/svcgssd_proc.c

   1 /*
   2  * svc_in_gssd_proc.c
   3  *
   4  * Copyright (c) 2000 The Regents of the University of Michigan.
   5  * All rights reserved.
   6  *
   7  * Copyright (c) 2002 Bruce Fields <bfields@UMICH.EDU>
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  *
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  * 3. Neither the name of the University nor the names of its
  19  *    contributors may be used to endorse or promote products derived
  20  *    from this software without specific prior written permission.
  21  *
  22  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
  23  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  24  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  25  * DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  27  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  28  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
  29  * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  30  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  31  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  32  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  33  */
  34
  35 #include <sys/param.h>
  36 #include <sys/stat.h>
  37
  38 #include <inttypes.h>
  39 #include <pwd.h>
  40 #include <stdio.h>
  41 #include <unistd.h>
  42 #include <ctype.h>
  43 #include <string.h>
  44 #include <fcntl.h>
  45 #include <errno.h>
  46 #ifdef HAVE_NETDB_H
  47 # include <netdb.h>
  48 #endif
  49
  50 #include <stdbool.h>
  51
  52 #include "svcgssd.h"
  53 #include "gss_util.h"
  54 #include "err_util.h"
  55 #include "context.h"
  56 #include "cacheio.h"
  57 #include "lsupport.h"
  58 #include "gss_oids.h"
  59 #include "sk_utils.h"
  60 #include <lustre/lustre_idl.h>
  61
  62 #define SVCGSSD_CONTEXT_CHANNEL "/proc/net/rpc/auth.sptlrpc.context/channel"
  63 #define SVCGSSD_INIT_CHANNEL    "/proc/net/rpc/auth.sptlrpc.init/channel"
  64
  65 #define TOKEN_BUF_SIZE          8192
  66
  67 struct svc_cred {
  68         uint32_t cr_remote;
  69         uint32_t cr_usr_root;
  70         uint32_t cr_usr_mds;
  71         uint32_t cr_usr_oss;
  72         uid_t    cr_uid;
  73         uid_t    cr_mapped_uid;
  74         uid_t    cr_gid;
  75 };
  76
  77 struct svc_nego_data {
  78         /* kernel data*/
  79         uint32_t        lustre_svc;
  80         lnet_nid_t      nid;
  81         uint64_t        handle_seq;
  82         char            nm_name[LUSTRE_NODEMAP_NAME_LENGTH + 1];
  83         gss_buffer_desc in_tok;
  84         gss_buffer_desc out_tok;
  85         gss_buffer_desc in_handle;
  86         gss_buffer_desc out_handle;
  87         uint32_t        maj_stat;
  88         uint32_t        min_stat;
  89
  90         /* userspace data */
  91         gss_OID                 mech;
  92         gss_ctx_id_t            ctx;
  93         gss_buffer_desc         ctx_token;
  94 };
  95
  96 static int
  97 do_svc_downcall(gss_buffer_desc *out_handle, struct svc_cred *cred,
  98                 gss_OID mechoid, gss_buffer_desc *context_token)
  99 {
 100         FILE *f;
 101         const char *mechname;
 102         int err;
 103
 104         printerr(2, "doing downcall\n");
 105         mechname = gss_OID_mech_name(mechoid);
 106         if (mechname == NULL)
 107                 goto out_err;
 108         f = fopen(SVCGSSD_CONTEXT_CHANNEL, "w");
 109         if (f == NULL) {
 110                 printerr(0, "WARNING: unable to open downcall channel "
 111                              "%s: %s\n",
 112                              SVCGSSD_CONTEXT_CHANNEL, strerror(errno));
 113                 goto out_err;
 114         }
 115         qword_printhex(f, out_handle->value, out_handle->length);
 116         /* XXX are types OK for the rest of this? */
 117         qword_printint(f, 3600); /* an hour should be sufficient */
 118         qword_printint(f, cred->cr_remote);
 119         qword_printint(f, cred->cr_usr_root);
 120         qword_printint(f, cred->cr_usr_mds);
 121         qword_printint(f, cred->cr_usr_oss);
 122         qword_printint(f, cred->cr_mapped_uid);
 123         qword_printint(f, cred->cr_uid);
 124         qword_printint(f, cred->cr_gid);
 125         qword_print(f, mechname);
 126         qword_printhex(f, context_token->value, context_token->length);
 127         err = qword_eol(f);
 128         fclose(f);
 129         return err;
 130 out_err:
 131         printerr(0, "WARNING: downcall failed\n");
 132         return -1;
 133 }
 134
 135 struct gss_verifier {
 136         u_int32_t       flav;
 137         gss_buffer_desc body;
 138 };
 139
 140 #define RPCSEC_GSS_SEQ_WIN      5
 141
 142 static int
 143 send_response(FILE *f, gss_buffer_desc *in_handle, gss_buffer_desc *in_token,
 144               u_int32_t maj_stat, u_int32_t min_stat,
 145               gss_buffer_desc *out_handle, gss_buffer_desc *out_token)
 146 {
 147         char buf[2 * TOKEN_BUF_SIZE];
 148         char *bp = buf;
 149         int blen = sizeof(buf);
 150         /* XXXARG: */
 151         int g;
 152
 153         printerr(2, "sending reply\n");
 154         qword_addhex(&bp, &blen, in_handle->value, in_handle->length);
 155         qword_addhex(&bp, &blen, in_token->value, in_token->length);
 156         qword_addint(&bp, &blen, 3600); /* an hour should be sufficient */
 157         qword_adduint(&bp, &blen, maj_stat);
 158         qword_adduint(&bp, &blen, min_stat);
 159         qword_addhex(&bp, &blen, out_handle->value, out_handle->length);
 160         qword_addhex(&bp, &blen, out_token->value, out_token->length);
 161         qword_addeol(&bp, &blen);
 162         if (blen <= 0) {
 163                 printerr(0, "WARNING: send_response: message too long\n");
 164                 return -1;
 165         }
 166         g = open(SVCGSSD_INIT_CHANNEL, O_WRONLY);
 167         if (g == -1) {
 168                 printerr(0, "WARNING: open %s failed: %s\n",
 169                                 SVCGSSD_INIT_CHANNEL, strerror(errno));
 170                 return -1;
 171         }
 172         *bp = '\0';
 173         printerr(3, "writing message: %s", buf);
 174         if (write(g, buf, bp - buf) == -1) {
 175                 printerr(0, "WARNING: failed to write message\n");
 176                 close(g);
 177                 return -1;
 178         }
 179         close(g);
 180         return 0;
 181 }
 182
 183 #define rpc_auth_ok                     0
 184 #define rpc_autherr_badcred             1
 185 #define rpc_autherr_rejectedcred        2
 186 #define rpc_autherr_badverf             3
 187 #define rpc_autherr_rejectedverf        4
 188 #define rpc_autherr_tooweak             5
 189 #define rpcsec_gsserr_credproblem       13
 190 #define rpcsec_gsserr_ctxproblem        14
 191
 192 static int
 193 get_ids(gss_name_t client_name, gss_OID mech, struct svc_cred *cred,
 194         lnet_nid_t nid, uint32_t lustre_svc)
 195 {
 196         u_int32_t       maj_stat, min_stat;
 197         gss_buffer_desc name;
 198         char            *sname, *host, *realm;
 199         const int       namebuf_size = 512;
 200         char            namebuf[namebuf_size];
 201         int             res = -1;
 202         gss_OID         name_type = GSS_C_NO_OID;
 203         struct passwd   *pw;
 204
 205         cred->cr_remote = 0;
 206         cred->cr_usr_root = cred->cr_usr_mds = cred->cr_usr_oss = 0;
 207         cred->cr_uid = cred->cr_mapped_uid = cred->cr_gid = -1;
 208
 209         maj_stat = gss_display_name(&min_stat, client_name, &name, &name_type);
 210         if (maj_stat != GSS_S_COMPLETE) {
 211                 pgsserr("get_ids: gss_display_name",
 212                         maj_stat, min_stat, mech);
 213                 return -1;
 214         }
 215         if (name.length >= 0xffff || /* be certain name.length+1 doesn't overflow */
 216             !(sname = calloc(name.length + 1, 1))) {
 217                 printerr(0, "WARNING: get_ids: error allocating %zu bytes "
 218                         "for sname\n", name.length + 1);
 219                 gss_release_buffer(&min_stat, &name);
 220                 return -1;
 221         }
 222         memcpy(sname, name.value, name.length);
 223         sname[name.length] = '\0';
 224         gss_release_buffer(&min_stat, &name);
 225
 226         if (lustre_svc == LUSTRE_GSS_SVC_MDS)
 227                 lookup_mapping(sname, nid, &cred->cr_mapped_uid);
 228         else
 229                 cred->cr_mapped_uid = -1;
 230
 231         realm = strchr(sname, '@');
 232         if (realm) {
 233                 *realm++ = '\0';
 234         } else {
 235                 printerr(0, "ERROR: %s has no realm name\n", sname);
 236                 goto out_free;
 237         }
 238
 239         host = strchr(sname, '/');
 240         if (host)
 241                 *host++ = '\0';
 242
 243         if (strcmp(sname, GSSD_SERVICE_MGS) == 0) {
 244                 printerr(0, "forbid %s as a user name\n", sname);
 245                 goto out_free;
 246         }
 247
 248         /* 1. check host part */
 249         if (host) {
 250                 if (lnet_nid2hostname(nid, namebuf, namebuf_size)) {
 251                         printerr(0, "ERROR: failed to resolve hostname for "
 252                                  "%s/%s@%s from %016llx\n",
 253                                  sname, host, realm, nid);
 254                         goto out_free;
 255                 }
 256
 257                 if (strcasecmp(host, namebuf)) {
 258                         printerr(0, "ERROR: %s/%s@%s claimed hostname doesn't "
 259                                  "match %s, nid %016llx\n", sname, host, realm,
 260                                  namebuf, nid);
 261                         goto out_free;
 262                 }
 263         } else {
 264                 if (!strcmp(sname, GSSD_SERVICE_MDS) ||
 265                     !strcmp(sname, GSSD_SERVICE_OSS)) {
 266                         printerr(0, "ERROR: %s@%s from %016llx doesn't "
 267                                  "bind with hostname\n", sname, realm, nid);
 268                         goto out_free;
 269                 }
 270         }
 271
 272         /* 2. check realm and user */
 273         switch (lustre_svc) {
 274         case LUSTRE_GSS_SVC_MDS:
 275                 if (strcasecmp(mds_local_realm, realm)) {
 276                         cred->cr_remote = 1;
 277
 278                         /* only allow mapped user from remote realm */
 279                         if (cred->cr_mapped_uid == -1) {
 280                                 printerr(0, "ERROR: %s%s%s@%s from %016llx "
 281                                          "is remote but without mapping\n",
 282                                          sname, host ? "/" : "",
 283                                          host ? host : "", realm, nid);
 284                                 break;
 285                         }
 286                 } else {
 287                         if (!strcmp(sname, LUSTRE_ROOT_NAME)) {
 288                                 cred->cr_uid = 0;
 289                                 cred->cr_usr_root = 1;
 290                         } else if (!strcmp(sname, GSSD_SERVICE_MDS)) {
 291                                 cred->cr_uid = 0;
 292                                 cred->cr_usr_mds = 1;
 293                         } else if (!strcmp(sname, GSSD_SERVICE_OSS)) {
 294                                 cred->cr_uid = 0;
 295                                 cred->cr_usr_oss = 1;
 296                         } else {
 297                                 pw = getpwnam(sname);
 298                                 if (pw != NULL) {
 299                                         cred->cr_uid = pw->pw_uid;
 300                                         printerr(2, "%s resolve to uid %u\n",
 301                                                  sname, cred->cr_uid);
 302                                 } else if (cred->cr_mapped_uid != -1) {
 303                                         printerr(2, "user %s from %016llx is "
 304                                                  "mapped to %u\n", sname, nid,
 305                                                  cred->cr_mapped_uid);
 306                                 } else {
 307                                         printerr(0, "ERROR: invalid user, "
 308                                                  "%s/%s@%s from %016llx\n",
 309                                                  sname, host, realm, nid);
 310                                         break;
 311                                 }
 312                         }
 313                 }
 314
 315                 res = 0;
 316                 break;
 317         case LUSTRE_GSS_SVC_MGS:
 318                 if (!strcmp(sname, GSSD_SERVICE_OSS)) {
 319                         cred->cr_uid = 0;
 320                         cred->cr_usr_oss = 1;
 321                 }
 322                 /* fall through */
 323         case LUSTRE_GSS_SVC_OSS:
 324                 if (!strcmp(sname, LUSTRE_ROOT_NAME)) {
 325                         cred->cr_uid = 0;
 326                         cred->cr_usr_root = 1;
 327                 } else if (!strcmp(sname, GSSD_SERVICE_MDS)) {
 328                         cred->cr_uid = 0;
 329                         cred->cr_usr_mds = 1;
 330                 }
 331                 if (cred->cr_uid == -1) {
 332                         printerr(0, "ERROR: svc %d doesn't accept user %s "
 333                                  "from %016llx\n", lustre_svc, sname, nid);
 334                         break;
 335                 }
 336                 res = 0;
 337                 break;
 338         default:
 339                 assert(0);
 340         }
 341
 342 out_free:
 343         if (!res)
 344                 printerr(1, "%s: authenticated %s%s%s@%s from %016llx\n",
 345                          lustre_svc_name[lustre_svc], sname,
 346                          host ? "/" : "", host ? host : "", realm, nid);
 347         free(sname);
 348         return res;
 349 }
 350
 351 typedef struct gss_union_ctx_id_t {
 352         gss_OID         mech_type;
 353         gss_ctx_id_t    internal_ctx_id;
 354 } gss_union_ctx_id_desc, *gss_union_ctx_id_t;
 355
 356 int handle_sk(struct svc_nego_data *snd)
 357 {
 358 #ifdef HAVE_OPENSSL_SSK
 359         struct sk_cred *skc = NULL;
 360         struct svc_cred cred;
 361         gss_buffer_desc bufs[SK_INIT_BUFFERS];
 362         gss_buffer_desc remote_pub_key = GSS_C_EMPTY_BUFFER;
 363         char *target;
 364         uint32_t rc = GSS_S_DEFECTIVE_TOKEN;
 365         uint32_t version;
 366         uint32_t flags;
 367         int i;
 368
 369         printerr(3, "Handling sk request\n");
 370         memset(bufs, 0, sizeof(gss_buffer_desc) * SK_INIT_BUFFERS);
 371
 372         /* See lgss_sk_using_cred() for client side token formation.
 373          * Decoding initiator buffers */
 374         i = sk_decode_netstring(bufs, SK_INIT_BUFFERS, &snd->in_tok);
 375         if (i < SK_INIT_BUFFERS) {
 376                 printerr(0, "Invalid netstring token received from peer\n");
 377                 goto cleanup_buffers;
 378         }
 379
 380         /* Allowing for a larger length first buffer in the future */
 381         if (bufs[SK_INIT_VERSION].length < sizeof(version)) {
 382                 printerr(0, "Invalid version received (wrong size)\n");
 383                 goto cleanup_buffers;
 384         }
 385         memcpy(&version, bufs[SK_INIT_VERSION].value, sizeof(version));
 386         version = be32toh(version);
 387         if (version != SK_MSG_VERSION) {
 388                 printerr(0, "Invalid version received: %d\n", version);
 389                 goto cleanup_buffers;
 390         }
 391
 392         rc = GSS_S_FAILURE;
 393
 394         /* target must be a null terminated string */
 395         i = bufs[SK_INIT_TARGET].length - 1;
 396         target = bufs[SK_INIT_TARGET].value;
 397         if (i >= 0 && target[i] != '\0') {
 398                 printerr(0, "Invalid target from netstring\n");
 399                 goto cleanup_buffers;
 400         }
 401
 402         if (bufs[SK_INIT_FLAGS].length != sizeof(flags)) {
 403                 printerr(0, "Invalid flags from netstring\n");
 404                 goto cleanup_buffers;
 405         }
 406         memcpy(&flags, bufs[SK_INIT_FLAGS].value, sizeof(flags));
 407
 408         skc = sk_create_cred(target, snd->nm_name, be32toh(flags));
 409         if (!skc) {
 410                 printerr(0, "Failed to create sk credentials\n");
 411                 goto cleanup_buffers;
 412         }
 413
 414         /* Verify that the peer has used a prime size greater or equal to
 415          * the size specified in the key file which may contain only zero
 416          * fill but the size specifies the mimimum supported size on
 417          * servers */
 418         if (skc->sc_flags & LGSS_SVC_PRIV &&
 419             bufs[SK_INIT_P].length < skc->sc_p.length) {
 420                 printerr(0, "Peer DHKE prime does not meet the size required "
 421                          "by keyfile: %zd bits\n", skc->sc_p.length * 8);
 422                 goto cleanup_buffers;
 423         }
 424
 425         /* Throw out the p from the server and use the wire data */
 426         free(skc->sc_p.value);
 427         skc->sc_p.value = NULL;
 428         skc->sc_p.length = 0;
 429
 430         /* Take control of all the allocated buffers from decoding */
 431         if (bufs[SK_INIT_RANDOM].length !=
 432             sizeof(skc->sc_kctx.skc_peer_random)) {
 433                 printerr(0, "Invalid size for client random\n");
 434                 goto cleanup_buffers;
 435         }
 436
 437         memcpy(&skc->sc_kctx.skc_peer_random, bufs[SK_INIT_RANDOM].value,
 438                sizeof(skc->sc_kctx.skc_peer_random));
 439         skc->sc_p = bufs[SK_INIT_P];
 440         remote_pub_key = bufs[SK_INIT_PUB_KEY];
 441         skc->sc_nodemap_hash = bufs[SK_INIT_NODEMAP];
 442         skc->sc_hmac = bufs[SK_INIT_HMAC];
 443
 444         /* Verify HMAC from peer.  Ideally this would happen before anything
 445          * else but we don't have enough information to lookup key without the
 446          * token (fsname and cluster_hash) so it's done after. */
 447         rc = sk_verify_hmac(skc, bufs, SK_INIT_BUFFERS - 1, EVP_sha256(),
 448                             &skc->sc_hmac);
 449         if (rc != GSS_S_COMPLETE) {
 450                 printerr(0, "HMAC verification error: 0x%x from peer %s\n",
 451                          rc, libcfs_nid2str((lnet_nid_t)snd->nid));
 452                 goto cleanup_partial;
 453         }
 454
 455         /* Check that the cluster hash matches the hash of nodemap name */
 456         rc = sk_verify_hash(snd->nm_name, EVP_sha256(), &skc->sc_nodemap_hash);
 457         if (rc != GSS_S_COMPLETE) {
 458                 printerr(0, "Cluster hash failed validation: 0x%x\n", rc);
 459                 goto cleanup_partial;
 460         }
 461
 462         rc = sk_gen_params(skc);
 463         if (rc != GSS_S_COMPLETE) {
 464                 printerr(0, "Failed to generate DH params for responder\n");
 465                 goto cleanup_partial;
 466         }
 467         if (sk_compute_dh_key(skc, &remote_pub_key)) {
 468                 printerr(0, "Failed to compute session key from DH params\n");
 469                 goto cleanup_partial;
 470         }
 471
 472         /* Cleanup init buffers we have copied or don't need anymore */
 473         free(bufs[SK_INIT_VERSION].value);
 474         free(bufs[SK_INIT_RANDOM].value);
 475         free(bufs[SK_INIT_TARGET].value);
 476         free(bufs[SK_INIT_FLAGS].value);
 477
 478         /* Server reply contains the servers public key, random,  and HMAC */
 479         version = htobe32(SK_MSG_VERSION);
 480         bufs[SK_RESP_VERSION].value = &version;
 481         bufs[SK_RESP_VERSION].length = sizeof(version);
 482         bufs[SK_RESP_RANDOM].value = &skc->sc_kctx.skc_host_random;
 483         bufs[SK_RESP_RANDOM].length = sizeof(skc->sc_kctx.skc_host_random);
 484         bufs[SK_RESP_PUB_KEY] = skc->sc_pub_key;
 485         if (sk_sign_bufs(&skc->sc_kctx.skc_shared_key, bufs,
 486                          SK_RESP_BUFFERS - 1, EVP_sha256(),
 487                          &skc->sc_hmac)) {
 488                 printerr(0, "Failed to sign parameters\n");
 489                 goto out_err;
 490         }
 491         bufs[SK_RESP_HMAC] = skc->sc_hmac;
 492         if (sk_encode_netstring(bufs, SK_RESP_BUFFERS, &snd->out_tok)) {
 493                 printerr(0, "Failed to encode netstring for token\n");
 494                 goto out_err;
 495         }
 496         printerr(2, "Created netstring of %zd bytes\n", snd->out_tok.length);
 497
 498         if (sk_session_kdf(skc, snd->nid, &snd->in_tok, &snd->out_tok)) {
 499                 printerr(0, "Failed to calulate derviced session key\n");
 500                 goto out_err;
 501         }
 502         if (sk_compute_keys(skc)) {
 503                 printerr(0, "Failed to compute HMAC and encryption keys\n");
 504                 goto out_err;
 505         }
 506         if (sk_serialize_kctx(skc, &snd->ctx_token)) {
 507                 printerr(0, "Failed to serialize context for kernel\n");
 508                 goto out_err;
 509         }
 510
 511         snd->out_handle.length = sizeof(snd->handle_seq);
 512         memcpy(snd->out_handle.value, &snd->handle_seq,
 513                sizeof(snd->handle_seq));
 514         snd->maj_stat = GSS_S_COMPLETE;
 515
 516         /* fix credentials */
 517         memset(&cred, 0, sizeof(cred));
 518         cred.cr_mapped_uid = -1;
 519
 520         if (skc->sc_flags & LGSS_ROOT_CRED_ROOT)
 521                 cred.cr_usr_root = 1;
 522         if (skc->sc_flags & LGSS_ROOT_CRED_MDT)
 523                 cred.cr_usr_mds = 1;
 524         if (skc->sc_flags & LGSS_ROOT_CRED_OST)
 525                 cred.cr_usr_oss = 1;
 526
 527         do_svc_downcall(&snd->out_handle, &cred, snd->mech, &snd->ctx_token);
 528
 529         /* cleanup ctx_token, out_tok is cleaned up in handle_channel_req */
 530         free(remote_pub_key.value);
 531         free(snd->ctx_token.value);
 532         snd->ctx_token.length = 0;
 533
 534         printerr(3, "sk returning success\n");
 535         return 0;
 536
 537 cleanup_buffers:
 538         for (i = 0; i < SK_INIT_BUFFERS; i++)
 539                 free(bufs[i].value);
 540         sk_free_cred(skc);
 541         snd->maj_stat = rc;
 542         return -1;
 543
 544 cleanup_partial:
 545         free(bufs[SK_INIT_VERSION].value);
 546         free(bufs[SK_INIT_RANDOM].value);
 547         free(bufs[SK_INIT_TARGET].value);
 548         free(bufs[SK_INIT_FLAGS].value);
 549         free(remote_pub_key.value);
 550         sk_free_cred(skc);
 551         snd->maj_stat = rc;
 552         return -1;
 553
 554 out_err:
 555         snd->maj_stat = rc;
 556         if (snd->ctx_token.value) {
 557                 free(snd->ctx_token.value);
 558                 snd->ctx_token.value = 0;
 559                 snd->ctx_token.length = 0;
 560         }
 561         free(remote_pub_key.value);
 562         sk_free_cred(skc);
 563         printerr(3, "sk returning failure\n");
 564 #else /* !HAVE_OPENSSL_SSK */
 565         printerr(0, "ERROR: shared key subflavour is not enabled\n");
 566 #endif /* HAVE_OPENSSL_SSK */
 567         return -1;
 568 }
 569
 570 int handle_null(struct svc_nego_data *snd)
 571 {
 572         struct svc_cred cred;
 573         uint64_t tmp;
 574         uint32_t flags;
 575
 576         /* null just uses the same token as the return token and for
 577          * for sending to the kernel.  It is a single uint64_t. */
 578         if (snd->in_tok.length != sizeof(uint64_t)) {
 579                 snd->maj_stat = GSS_S_DEFECTIVE_TOKEN;
 580                 printerr(0, "Invalid token size (%zd) received\n",
 581                          snd->in_tok.length);
 582                 return -1;
 583         }
 584         snd->out_tok.length = snd->in_tok.length;
 585         snd->out_tok.value = malloc(snd->out_tok.length);
 586         if (!snd->out_tok.value) {
 587                 snd->maj_stat = GSS_S_FAILURE;
 588                 printerr(0, "Failed to allocate out_tok\n");
 589                 return -1;
 590         }
 591
 592         snd->ctx_token.length = snd->in_tok.length;
 593         snd->ctx_token.value = malloc(snd->ctx_token.length);
 594         if (!snd->ctx_token.value) {
 595                 snd->maj_stat = GSS_S_FAILURE;
 596                 printerr(0, "Failed to allocate ctx_token\n");
 597                 return -1;
 598         }
 599
 600         snd->out_handle.length = sizeof(snd->handle_seq);
 601         memcpy(snd->out_handle.value, &snd->handle_seq,
 602                sizeof(snd->handle_seq));
 603         snd->maj_stat = GSS_S_COMPLETE;
 604
 605         memcpy(&tmp, snd->in_tok.value, sizeof(tmp));
 606         tmp = be64toh(tmp);
 607         flags = (uint32_t)(tmp & 0x00000000ffffffff);
 608         memset(&cred, 0, sizeof(cred));
 609         cred.cr_mapped_uid = -1;
 610
 611         if (flags & LGSS_ROOT_CRED_ROOT)
 612                 cred.cr_usr_root = 1;
 613         if (flags & LGSS_ROOT_CRED_MDT)
 614                 cred.cr_usr_mds = 1;
 615         if (flags & LGSS_ROOT_CRED_OST)
 616                 cred.cr_usr_oss = 1;
 617
 618         do_svc_downcall(&snd->out_handle, &cred, snd->mech, &snd->ctx_token);
 619
 620         /* cleanup ctx_token, out_tok is cleaned up in handle_channel_req */
 621         free(snd->ctx_token.value);
 622         snd->ctx_token.length = 0;
 623
 624         return 0;
 625 }
 626
 627 static int handle_krb(struct svc_nego_data *snd)
 628 {
 629         u_int32_t               ret_flags;
 630         gss_name_t              client_name;
 631         gss_buffer_desc         ignore_out_tok = {.value = NULL};
 632         gss_OID                 mech = GSS_C_NO_OID;
 633         gss_cred_id_t           svc_cred;
 634         u_int32_t               ignore_min_stat;
 635         struct svc_cred         cred;
 636
 637         svc_cred = gssd_select_svc_cred(snd->lustre_svc);
 638         if (!svc_cred) {
 639                 printerr(0, "no service credential for svc %u\n",
 640                          snd->lustre_svc);
 641                 goto out_err;
 642         }
 643
 644         snd->maj_stat = gss_accept_sec_context(&snd->min_stat, &snd->ctx,
 645                                                svc_cred, &snd->in_tok,
 646                                                GSS_C_NO_CHANNEL_BINDINGS,
 647                                                &client_name, &mech,
 648                                                &snd->out_tok, &ret_flags, NULL,
 649                                                NULL);
 650
 651         if (snd->maj_stat == GSS_S_CONTINUE_NEEDED) {
 652                 printerr(1, "gss_accept_sec_context GSS_S_CONTINUE_NEEDED\n");
 653
 654                 /* Save the context handle for future calls */
 655                 snd->out_handle.length = sizeof(snd->ctx);
 656                 memcpy(snd->out_handle.value, &snd->ctx, sizeof(snd->ctx));
 657                 return 0;
 658         } else if (snd->maj_stat != GSS_S_COMPLETE) {
 659                 printerr(0, "WARNING: gss_accept_sec_context failed\n");
 660                 pgsserr("handle_krb: gss_accept_sec_context",
 661                         snd->maj_stat, snd->min_stat, mech);
 662                 goto out_err;
 663         }
 664
 665         if (get_ids(client_name, mech, &cred, snd->nid, snd->lustre_svc)) {
 666                 /* get_ids() prints error msg */
 667                 snd->maj_stat = GSS_S_BAD_NAME; /* XXX ? */
 668                 gss_release_name(&ignore_min_stat, &client_name);
 669                 goto out_err;
 670         }
 671         gss_release_name(&ignore_min_stat, &client_name);
 672
 673         /* Context complete. Pass handle_seq in out_handle to use
 674          * for context lookup in the kernel. */
 675         snd->out_handle.length = sizeof(snd->handle_seq);
 676         memcpy(snd->out_handle.value, &snd->handle_seq,
 677                sizeof(snd->handle_seq));
 678
 679         /* kernel needs ctx to calculate verifier on null response, so
 680          * must give it context before doing null call: */
 681         if (serialize_context_for_kernel(snd->ctx, &snd->ctx_token, mech)) {
 682                 printerr(0, "WARNING: handle_krb: "
 683                          "serialize_context_for_kernel failed\n");
 684                 snd->maj_stat = GSS_S_FAILURE;
 685                 goto out_err;
 686         }
 687         /* We no longer need the gss context */
 688         gss_delete_sec_context(&ignore_min_stat, &snd->ctx, &ignore_out_tok);
 689         do_svc_downcall(&snd->out_handle, &cred, mech, &snd->ctx_token);
 690
 691         return 0;
 692
 693 out_err:
 694         if (snd->ctx != GSS_C_NO_CONTEXT)
 695                 gss_delete_sec_context(&ignore_min_stat, &snd->ctx,
 696                                        &ignore_out_tok);
 697
 698         return 1;
 699 }
 700
 701 /*
 702  * return -1 only if we detect error during reading from upcall channel,
 703  * all other cases return 0.
 704  */
 705 int handle_channel_request(FILE *f)
 706 {
 707         char                    in_tok_buf[TOKEN_BUF_SIZE];
 708         char                    in_handle_buf[15];
 709         char                    out_handle_buf[15];
 710         gss_buffer_desc         ctx_token      = {.value = NULL},
 711                                 null_token     = {.value = NULL};
 712         uint32_t                lustre_mech;
 713         static char             *lbuf;
 714         static int              lbuflen;
 715         static char             *cp;
 716         int                     get_len;
 717         int                     rc = 1;
 718         u_int32_t               ignore_min_stat;
 719         struct svc_nego_data    snd = {
 720                 .in_tok.value           = in_tok_buf,
 721                 .in_handle.value        = in_handle_buf,
 722                 .out_handle.value       = out_handle_buf,
 723                 .maj_stat               = GSS_S_FAILURE,
 724                 .ctx                    = GSS_C_NO_CONTEXT,
 725         };
 726
 727         printerr(2, "handling request\n");
 728         if (readline(fileno(f), &lbuf, &lbuflen) != 1) {
 729                 printerr(0, "WARNING: failed reading request\n");
 730                 return -1;
 731         }
 732
 733         cp = lbuf;
 734
 735         /* see rsi_request() for the format of data being input here */
 736         qword_get(&cp, (char *)&snd.lustre_svc, sizeof(snd.lustre_svc));
 737
 738         /* lustre_svc is the svc and gss subflavor */
 739         lustre_mech = (snd.lustre_svc & LUSTRE_GSS_MECH_MASK) >>
 740                       LUSTRE_GSS_MECH_SHIFT;
 741         snd.lustre_svc = snd.lustre_svc & LUSTRE_GSS_SVC_MASK;
 742         switch (lustre_mech) {
 743         case LGSS_MECH_KRB5:
 744                 if (!krb_enabled) {
 745                         static time_t next_krb;
 746
 747                         if (time(NULL) > next_krb) {
 748                                 printerr(1, "warning: Request for kerberos but "
 749                                          "service support not enabled\n");
 750                                 next_krb = time(NULL) + 3600;
 751                         }
 752                         goto ignore;
 753                 }
 754                 snd.mech = &krb5oid;
 755                 break;
 756         case LGSS_MECH_NULL:
 757                 if (!null_enabled) {
 758                         static time_t next_null;
 759
 760                         if (time(NULL) > next_null) {
 761                                 printerr(1, "warning: Request for gssnull but "
 762                                          "service support not enabled\n");
 763                                 next_null = time(NULL) + 3600;
 764                         }
 765                         goto ignore;
 766                 }
 767                 snd.mech = &nulloid;
 768                 break;
 769         case LGSS_MECH_SK:
 770                 if (!sk_enabled) {
 771                         static time_t next_ssk;
 772
 773                         if (time(NULL) > next_ssk) {
 774                                 printerr(1, "warning: Request for SSK but "
 775                                          "service support not %s\n",
 776 #ifdef HAVE_OPENSSL_SSK
 777                                          "enabled"
 778 #else
 779                                          "included"
 780 #endif
 781                                         );
 782                                 next_ssk = time(NULL) + 3600;
 783                         }
 784
 785                         goto ignore;
 786                 }
 787                 snd.mech = &skoid;
 788                 break;
 789         default:
 790                 printerr(0, "WARNING: invalid mechanism recevied: %d\n",
 791                          lustre_mech);
 792                 goto out_err;
 793                 break;
 794         }
 795
 796         qword_get(&cp, (char *)&snd.nid, sizeof(snd.nid));
 797         qword_get(&cp, (char *)&snd.handle_seq, sizeof(snd.handle_seq));
 798         qword_get(&cp, snd.nm_name, sizeof(snd.nm_name));
 799         printerr(2, "handling req: svc %u, nid %016llx, idx %"PRIx64" nodemap "
 800                  "%s\n", snd.lustre_svc, snd.nid, snd.handle_seq, snd.nm_name);
 801
 802         get_len = qword_get(&cp, snd.in_handle.value, sizeof(in_handle_buf));
 803         if (get_len < 0) {
 804                 printerr(0, "WARNING: failed parsing request\n");
 805                 goto out_err;
 806         }
 807         snd.in_handle.length = (size_t)get_len;
 808
 809         printerr(3, "in_handle:\n");
 810         print_hexl(3, snd.in_handle.value, snd.in_handle.length);
 811
 812         get_len = qword_get(&cp, snd.in_tok.value, sizeof(in_tok_buf));
 813         if (get_len < 0) {
 814                 printerr(0, "WARNING: failed parsing request\n");
 815                 goto out_err;
 816         }
 817         snd.in_tok.length = (size_t)get_len;
 818
 819         printerr(3, "in_tok:\n");
 820         print_hexl(3, snd.in_tok.value, snd.in_tok.length);
 821
 822         if (snd.in_handle.length != 0) { /* CONTINUE_INIT case */
 823                 if (snd.in_handle.length != sizeof(snd.ctx)) {
 824                         printerr(0, "WARNING: input handle has unexpected "
 825                                  "length %zu\n", snd.in_handle.length);
 826                         goto out_err;
 827                 }
 828                 /* in_handle is the context id stored in the out_handle
 829                  * for the GSS_S_CONTINUE_NEEDED case below.  */
 830                 memcpy(&snd.ctx, snd.in_handle.value, snd.in_handle.length);
 831         }
 832
 833         if (lustre_mech == LGSS_MECH_KRB5)
 834                 rc = handle_krb(&snd);
 835         else if (lustre_mech == LGSS_MECH_SK)
 836                 rc = handle_sk(&snd);
 837         else if (lustre_mech == LGSS_MECH_NULL)
 838                 rc = handle_null(&snd);
 839         else
 840                 printerr(0, "WARNING: Received or request for"
 841                          "subflavor that is not enabled: %d\n", lustre_mech);
 842
 843 out_err:
 844         /* Failures send a null token */
 845         if (rc == 0)
 846                 send_response(f, &snd.in_handle, &snd.in_tok, snd.maj_stat,
 847                               snd.min_stat, &snd.out_handle, &snd.out_tok);
 848         else
 849                 send_response(f, &snd.in_handle, &snd.in_tok, snd.maj_stat,
 850                               snd.min_stat, &null_token, &null_token);
 851
 852         /* cleanup buffers */
 853         if (snd.ctx_token.value != NULL)
 854                 free(ctx_token.value);
 855         if (snd.out_tok.value != NULL)
 856                 gss_release_buffer(&ignore_min_stat, &snd.out_tok);
 857
 858         /* For junk wire data just ignore */
 859 ignore:
 860         return 0;
 861 }