lustre/utils/gss/lgss_keyring.c

   1 /*
   2  * GPL HEADER START
   3  *
   4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 only,
   8  * as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * General Public License version 2 for more details (a copy is included
  14  * in the LICENSE file that accompanied this code).
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * version 2 along with this program; If not, see
  18  * http://www.gnu.org/licenses/gpl-2.0.html
  19  *
  20  * GPL HEADER END
  21  */
  22 /*
  23  * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved.
  24  * Use is subject to license terms.
  25  *
  26  * Copyright (c) 2011, Intel Corporation.
  27  */
  28 /*
  29  * This file is part of Lustre, http://www.lustre.org/
  30  *
  31  * lustre/utils/gss/lgss_keyring.c
  32  *
  33  * user-space upcall to create GSS context, using keyring interface to kernel
  34  *
  35  * Author: Eric Mei <ericm@clusterfs.com>
  36  */
  37
  38 #include <sched.h>
  39 #include <sys/types.h>
  40 #include <sys/stat.h>
  41 #include <unistd.h>
  42 #include <stdlib.h>
  43 #include <stdio.h>
  44 #include <fcntl.h>
  45 #include <inttypes.h>
  46 #include <string.h>
  47 #include <errno.h>
  48 #include <pwd.h>
  49 #include <keyutils.h>
  50 #include <gssapi/gssapi.h>
  51 #include <sys/wait.h>
  52 #include <getopt.h>
  53
  54 #include <libcfs/util/param.h>
  55 #include <libcfs/util/string.h>
  56 #include <uapi/linux/lustre/lgss.h>
  57 #include "lsupport.h"
  58 #include "lgss_utils.h"
  59 #include "lgss_krb5_utils.h"
  60 #include "write_bytes.h"
  61 #include "context.h"
  62
  63 /*
  64  * gss target string of lustre service we are negotiating for
  65  */
  66 static char *g_service = NULL;
  67
  68 /*
  69  * all data about negotiation
  70  */
  71 struct lgss_nego_data {
  72         uint32_t        lnd_established:1;
  73
  74         int             lnd_secid;
  75         uint32_t        lnd_uid;
  76         uint32_t        lnd_lsvc;
  77         char            *lnd_uuid;
  78
  79         gss_OID         lnd_mech;               /* mech OID */
  80         gss_name_t      lnd_svc_name;           /* service name */
  81         unsigned int    lnd_req_flags;          /* request flags */
  82         gss_cred_id_t   lnd_cred;               /* credential */
  83         gss_ctx_id_t    lnd_ctx;                /* session context */
  84         gss_buffer_desc lnd_rmt_ctx;            /* remote handle of context */
  85         gss_buffer_desc lnd_ctx_token;          /* context token for kernel */
  86         uint32_t        lnd_seq_win;            /* sequence window */
  87
  88         int             lnd_rpc_err;
  89         int             lnd_gss_err;
  90 };
  91
  92 /*
  93  * context creation response
  94  */
  95 struct lgss_init_res {
  96         gss_buffer_desc gr_ctx;         /* context handle */
  97         unsigned int    gr_major;       /* major status */
  98         unsigned int    gr_minor;       /* minor status */
  99         unsigned int    gr_win;         /* sequence window */
 100         gss_buffer_desc gr_token;       /* token */
 101 };
 102
 103 struct keyring_upcall_param {
 104         uint32_t        kup_ver;
 105         uint32_t        kup_secid;
 106         uint32_t        kup_uid;
 107         uint32_t        kup_fsuid;
 108         uint32_t        kup_gid;
 109         uint32_t        kup_fsgid;
 110         uint32_t        kup_svc;
 111         uint64_t        kup_nid;
 112         uint64_t        kup_selfnid;
 113         char            kup_svc_type;
 114         char            kup_tgt[64];
 115         char            kup_mech[16];
 116         unsigned int    kup_is_root:1,
 117                         kup_is_mdt:1,
 118                         kup_is_ost:1;
 119         uint32_t        kup_pid;
 120 };
 121
 122 /****************************************
 123  * child process: gss negotiation       *
 124  ****************************************/
 125
 126 static int send_to(int fd, const void *buf, size_t size)
 127 {
 128         ssize_t sz;
 129
 130         sz = write(fd, buf, size);
 131         if (sz == -1) {
 132                 logmsg(LL_ERR, "cannot send to GSS process: %s\n",
 133                        strerror(errno));
 134                 return -errno;
 135         }
 136         if (sz < size) {
 137                 logmsg(LL_ERR, "short write sending to GSS process: %d/%d\n",
 138                        (int)sz, (int)size);
 139                 return -EPROTO;
 140         }
 141
 142         return 0;
 143 }
 144
 145 static int receive_from(int fd, void *buf, size_t size)
 146 {
 147         ssize_t sz;
 148
 149         sz = read(fd, buf, size);
 150         if (sz == -1) {
 151                 logmsg(LL_ERR, "cannot receive from GSS process: %s\n",
 152                        strerror(errno));
 153                 return -errno;
 154         }
 155         if (sz < size) {
 156                 logmsg(LL_ERR, "short read receiving from GSS process: %d/%d\n",
 157                        (int)sz, (int)size);
 158                 return -EPROTO;
 159         }
 160
 161         return 0;
 162 }
 163
 164 static int gss_do_ioctl(struct lgssd_ioctl_param *param)
 165 {
 166         int fd, ret;
 167         glob_t path;
 168         int rc;
 169
 170         rc = cfs_get_param_paths(&path, "sptlrpc/gss/init_channel");
 171         if (rc != 0)
 172                 return rc;
 173
 174         logmsg(LL_TRACE, "to open %s\n", path.gl_pathv[0]);
 175
 176         fd = open(path.gl_pathv[0], O_WRONLY);
 177         if (fd < 0) {
 178                 logmsg(LL_ERR, "can't open %s\n", path.gl_pathv[0]);
 179                 rc = -EACCES;
 180                 goto out_params;
 181         }
 182
 183         logmsg(LL_TRACE, "to down-write\n");
 184
 185         ret = write(fd, param, sizeof(*param));
 186         close(fd);
 187         if (ret != sizeof(*param)) {
 188                 logmsg(LL_ERR, "lustre ioctl err: %s\n", strerror(errno));
 189                 rc = -EACCES;
 190         }
 191
 192 out_params:
 193         cfs_free_param_data(&path);
 194         return rc;
 195 }
 196
 197 int do_nego_rpc(struct lgss_nego_data *lnd,
 198                 gss_buffer_desc *gss_token,
 199                 struct lgss_init_res *gr,
 200                 int req_fd[2], int reply_fd[2])
 201 {
 202         struct lgssd_ioctl_param param;
 203         struct passwd *pw;
 204         int res;
 205         char outbuf[8192] = { 0 };
 206         unsigned int *p;
 207         int rc = 0;
 208
 209         logmsg(LL_TRACE, "start negotiation rpc\n");
 210
 211         pw = getpwuid(lnd->lnd_uid);
 212         if (!pw) {
 213                 logmsg(LL_ERR, "no uid %u in local user database\n",
 214                        lnd->lnd_uid);
 215                 return -EACCES;
 216         }
 217
 218         param.version = GSSD_INTERFACE_VERSION;
 219         param.secid = lnd->lnd_secid;
 220         param.uuid = lnd->lnd_uuid;
 221         param.lustre_svc = lnd->lnd_lsvc;
 222         param.uid = lnd->lnd_uid;
 223         param.gid = pw->pw_gid;
 224         param.send_token_size = gss_token->length;
 225         param.send_token = (char *) gss_token->value;
 226
 227         if (req_fd[0] == -1 && reply_fd[0] == -1) {
 228                 /* we can do the ioctl directly */
 229                 param.reply_buf_size = sizeof(outbuf);
 230                 param.reply_buf = outbuf;
 231
 232                 rc = gss_do_ioctl(&param);
 233                 if (rc != 0)
 234                         return rc;
 235         } else {
 236                 /* looks like we are running in a container,
 237                  * so we cannot do the ioctl ourselves: delegate to
 238                  * parent process running directly on host */
 239
 240                 /* send ioctl buffer to parent */
 241                 rc = send_to(req_fd[1], &param, sizeof(param));
 242                 if (rc != 0)
 243                         return rc;
 244                 /* send gss token to parent */
 245                 rc = send_to(req_fd[1], gss_token->value, gss_token->length);
 246                 if (rc != 0)
 247                         return rc;
 248
 249                 /* read ioctl status from parent */
 250                 rc = receive_from(reply_fd[0], &param.status,
 251                                   sizeof(param.status));
 252                 if (rc != 0)
 253                         return rc;
 254
 255                 if (param.status == 0) {
 256                         /* read reply buffer from parent */
 257                         rc = receive_from(reply_fd[0], outbuf, sizeof(outbuf));
 258                         if (rc != 0)
 259                                 return rc;
 260                 }
 261         }
 262
 263         logmsg(LL_TRACE, "do_nego_rpc: to parse reply\n");
 264         if (param.status) {
 265                 logmsg(LL_ERR, "status: %ld (%s)\n",
 266                        (long int)param.status, strerror((int)(-param.status)));
 267                 return param.status;
 268         }
 269
 270         p = (unsigned int *)outbuf;
 271         res = *p++;
 272         gr->gr_major = *p++;
 273         gr->gr_minor = *p++;
 274         gr->gr_win = *p++;
 275
 276         gr->gr_ctx.length = *p++;
 277         gr->gr_ctx.value = malloc(gr->gr_ctx.length);
 278         if (gr->gr_ctx.value == NULL)
 279                 return -ENOMEM;
 280         memcpy(gr->gr_ctx.value, p, gr->gr_ctx.length);
 281         p += (((gr->gr_ctx.length + 3) & ~3) / 4);
 282
 283         gr->gr_token.length = *p++;
 284         gr->gr_token.value = malloc(gr->gr_token.length);
 285         if (gr->gr_token.value == NULL) {
 286                 free(gr->gr_ctx.value);
 287                 return -ENOMEM;
 288         }
 289         memcpy(gr->gr_token.value, p, gr->gr_token.length);
 290         p += (((gr->gr_token.length + 3) & ~3) / 4);
 291
 292         logmsg(LL_DEBUG, "do_nego_rpc: receive handle len %zu, token len %zu, "
 293                "res %d\n", gr->gr_ctx.length, gr->gr_token.length, res);
 294
 295         return rc;
 296 }
 297
 298 /* This is used by incomplete GSSAPI implementations that can't use
 299  * gss_init_sec_context and will parse the token themselves (gssnull and sk).
 300  * Callers should have cred->lc_mech_token pointing to a gss_buffer_desc
 301  * token to send to the peer as part of the SEC_CTX_INIT operation.  The return
 302  * RPC's token with be in gr.gr_token which is validated using
 303  * lgss_validate_cred. */
 304 static int lgssc_negotiation_manual(struct lgss_nego_data *lnd,
 305                                     struct lgss_cred *cred,
 306                                     int req_fd[2], int reply_fd[2])
 307 {
 308         struct lgss_init_res gr;
 309         OM_uint32 min_stat;
 310         int rc;
 311
 312         logmsg(LL_TRACE, "starting gss negotation\n");
 313         memset(&gr, 0, sizeof(gr));
 314
 315         lnd->lnd_rpc_err = do_nego_rpc(lnd, &cred->lc_mech_token, &gr,
 316                                        req_fd, reply_fd);
 317         if (lnd->lnd_rpc_err) {
 318                 logmsg(LL_ERR, "negotiation rpc error %d\n", lnd->lnd_rpc_err);
 319                 rc = lnd->lnd_rpc_err;
 320                 goto out_error;
 321         }
 322
 323         if (gr.gr_major == GSS_S_CONTINUE_NEEDED) {
 324                 rc = -EAGAIN;
 325                 goto out_error;
 326
 327         } else if (gr.gr_major != GSS_S_COMPLETE) {
 328                 lnd->lnd_gss_err = gr.gr_major;
 329                 logmsg(LL_ERR, "negotiation gss error %x\n", lnd->lnd_gss_err);
 330                 rc = -ENOTCONN;
 331                 goto out_error;
 332         }
 333
 334         if (gr.gr_ctx.length == 0 || gr.gr_token.length == 0) {
 335                 logmsg(LL_ERR, "zero length context or token received\n");
 336                 rc = -EINVAL;
 337                 goto out_error;
 338         }
 339
 340         rc = lgss_validate_cred(cred, &gr.gr_token, &lnd->lnd_ctx_token);
 341         if (rc) {
 342                 logmsg(LL_ERR, "peer token failed validation\n");
 343                 goto out_error;
 344         }
 345
 346         lnd->lnd_established = 1;
 347         lnd->lnd_seq_win = gr.gr_win;
 348         lnd->lnd_rmt_ctx = gr.gr_ctx;
 349
 350         if (gr.gr_token.length != 0)
 351                 gss_release_buffer(&min_stat, &gr.gr_token);
 352
 353         logmsg(LL_DEBUG, "successfully negotiated a context\n");
 354         return 0;
 355
 356 out_error:
 357         if (gr.gr_ctx.length != 0)
 358                 gss_release_buffer(&min_stat, &gr.gr_ctx);
 359         if (gr.gr_token.length != 0)
 360                 gss_release_buffer(&min_stat, &gr.gr_token);
 361
 362         return rc;
 363 }
 364
 365 /*
 366  * if return error, the lnd_rpc_err or lnd_gss_err is set.
 367  */
 368 static int lgssc_negotiation(struct lgss_nego_data *lnd, int req_fd[2],
 369                              int reply_fd[2])
 370 {
 371         struct lgss_init_res    gr;
 372         gss_buffer_desc        *recv_tokenp, send_token;
 373         OM_uint32               maj_stat, min_stat, ret_flags;
 374
 375         logmsg(LL_TRACE, "start gss negotiation\n");
 376
 377         /* GSS context establishment loop. */
 378         memset(&gr, 0, sizeof(gr));
 379         recv_tokenp = GSS_C_NO_BUFFER;
 380
 381         for (;;) {
 382                 maj_stat = gss_init_sec_context(&min_stat,
 383                                                 lnd->lnd_cred,
 384                                                 &lnd->lnd_ctx,
 385                                                 lnd->lnd_svc_name,
 386                                                 lnd->lnd_mech,
 387                                                 lnd->lnd_req_flags,
 388                                                 0,            /* time req */
 389                                                 NULL,         /* channel */
 390                                                 recv_tokenp,
 391                                                 NULL,         /* used mech */
 392                                                 &send_token,
 393                                                 &ret_flags,
 394                                                 NULL);        /* time rec */
 395
 396                 logmsg_gss(LL_TRACE, lnd->lnd_mech, maj_stat, min_stat,
 397                            "gss_init_sec_context");
 398
 399                 logmsg(LL_TRACE, "send_token:\n");
 400                 log_hexl(LL_TRACE, send_token.value, send_token.length);
 401
 402                 if (recv_tokenp != GSS_C_NO_BUFFER) {
 403                         gss_release_buffer(&min_stat, &gr.gr_token);
 404                         recv_tokenp = GSS_C_NO_BUFFER;
 405                 }
 406
 407                 if (maj_stat != GSS_S_COMPLETE &&
 408                     maj_stat != GSS_S_CONTINUE_NEEDED) {
 409                         lnd->lnd_gss_err = maj_stat;
 410
 411                         logmsg_gss(LL_ERR, lnd->lnd_mech, maj_stat, min_stat,
 412                                    "failed init context");
 413                         break;
 414                 }
 415
 416                 if (send_token.length != 0) {
 417                         memset(&gr, 0, sizeof(gr));
 418
 419                         lnd->lnd_rpc_err = do_nego_rpc(lnd, &send_token, &gr,
 420                                                        req_fd, reply_fd);
 421                         gss_release_buffer(&min_stat, &send_token);
 422
 423                         if (lnd->lnd_rpc_err) {
 424                                 logmsg(LL_ERR, "negotiation rpc error: %d\n",
 425                                        lnd->lnd_rpc_err);
 426                                 return lnd->lnd_rpc_err;
 427                         }
 428
 429                         if (gr.gr_major != GSS_S_COMPLETE &&
 430                             gr.gr_major != GSS_S_CONTINUE_NEEDED) {
 431                                 lnd->lnd_gss_err = gr.gr_major;
 432
 433                                 logmsg(LL_ERR, "negotiation gss error %x\n",
 434                                        lnd->lnd_gss_err);
 435                                 return -ENOTCONN;
 436                         }
 437
 438                         if (gr.gr_ctx.length != 0) {
 439                                 if (lnd->lnd_rmt_ctx.value)
 440                                         gss_release_buffer(&min_stat,
 441                                                            &lnd->lnd_rmt_ctx);
 442                                 lnd->lnd_rmt_ctx = gr.gr_ctx;
 443                         }
 444
 445                         if (gr.gr_token.length != 0) {
 446                                 if (maj_stat != GSS_S_CONTINUE_NEEDED)
 447                                         break;
 448                                 recv_tokenp = &gr.gr_token;
 449                         }
 450                 }
 451
 452                 /* GSS_S_COMPLETE => check gss header verifier,
 453                  * usually checked in gss_validate
 454                  */
 455                 if (maj_stat == GSS_S_COMPLETE) {
 456                         lnd->lnd_established = 1;
 457                         lnd->lnd_seq_win = gr.gr_win;
 458                         break;
 459                 }
 460         }
 461
 462         /* End context negotiation loop. */
 463         if (!lnd->lnd_established) {
 464                 if (gr.gr_token.length != 0)
 465                         gss_release_buffer(&min_stat, &gr.gr_token);
 466
 467                 if (lnd->lnd_gss_err == GSS_S_COMPLETE)
 468                         lnd->lnd_rpc_err = -EACCES;
 469
 470                 logmsg(LL_ERR, "context negotiation failed\n");
 471                 return -1;
 472         }
 473
 474         logmsg(LL_DEBUG, "successfully negotiated a context\n");
 475         return 0;
 476 }
 477
 478 /*
 479  * if return error, the lnd_rpc_err or lnd_gss_err is set.
 480  */
 481 static int lgssc_init_nego_data(struct lgss_nego_data *lnd,
 482                                 struct keyring_upcall_param *kup,
 483                                 enum lgss_mech mech)
 484 {
 485         gss_buffer_desc         sname;
 486         OM_uint32               maj_stat, min_stat;
 487
 488         memset(lnd, 0, sizeof(*lnd));
 489
 490         lnd->lnd_secid = kup->kup_secid;
 491         lnd->lnd_uid = kup->kup_uid;
 492         lnd->lnd_lsvc = kup->kup_svc | mech << LUSTRE_GSS_MECH_SHIFT;
 493         lnd->lnd_uuid = kup->kup_tgt;
 494
 495         lnd->lnd_established = 0;
 496         lnd->lnd_svc_name = GSS_C_NO_NAME;
 497         lnd->lnd_cred = GSS_C_NO_CREDENTIAL;
 498         lnd->lnd_ctx = GSS_C_NO_CONTEXT;
 499         lnd->lnd_rmt_ctx = (gss_buffer_desc) GSS_C_EMPTY_BUFFER;
 500         lnd->lnd_seq_win = 0;
 501
 502         switch (mech) {
 503         case LGSS_MECH_KRB5:
 504                 lnd->lnd_mech = (gss_OID)&krb5oid;
 505                 lnd->lnd_req_flags = GSS_C_MUTUAL_FLAG;
 506                 break;
 507         case LGSS_MECH_NULL:
 508                 lnd->lnd_mech = (gss_OID)&nulloid;
 509                 break;
 510 #ifdef HAVE_OPENSSL_SSK
 511         case LGSS_MECH_SK:
 512                 lnd->lnd_mech = (gss_OID)&skoid;
 513                 lnd->lnd_req_flags = GSS_C_MUTUAL_FLAG;
 514                 break;
 515 #endif
 516         default:
 517                 logmsg(LL_ERR, "invalid mech: %d\n", mech);
 518                 lnd->lnd_rpc_err = -EACCES;
 519                 return -1;
 520         }
 521
 522         sname.value = g_service;
 523         sname.length = strlen(g_service);
 524
 525         maj_stat = gss_import_name(&min_stat, &sname,
 526                                    (gss_OID) GSS_C_NT_HOSTBASED_SERVICE,
 527                                    &lnd->lnd_svc_name);
 528         if (maj_stat != GSS_S_COMPLETE) {
 529                 logmsg_gss(LL_ERR, lnd->lnd_mech, maj_stat, min_stat,
 530                            "can't import svc name");
 531                 lnd->lnd_gss_err = maj_stat;
 532                 return -1;
 533         }
 534
 535         return 0;
 536 }
 537
 538 void lgssc_fini_nego_data(struct lgss_nego_data *lnd)
 539 {
 540         OM_uint32       maj_stat, min_stat;
 541
 542         if (lnd->lnd_svc_name != GSS_C_NO_NAME) {
 543                 maj_stat = gss_release_name(&min_stat, &lnd->lnd_svc_name);
 544                 if (maj_stat != GSS_S_COMPLETE)
 545                         logmsg_gss(LL_ERR, lnd->lnd_mech, maj_stat, min_stat,
 546                                    "can't release service name");
 547         }
 548
 549         if (lnd->lnd_cred != GSS_C_NO_CREDENTIAL) {
 550                 maj_stat = gss_release_cred(&min_stat, &lnd->lnd_cred);
 551                 if (maj_stat != GSS_S_COMPLETE)
 552                         logmsg_gss(LL_ERR, lnd->lnd_mech, maj_stat, min_stat,
 553                                    "can't release credential");
 554         }
 555 }
 556
 557 static
 558 int error_kernel_key(key_serial_t keyid, int rpc_error, int gss_error)
 559 {
 560         int      seqwin = 0;
 561         char     buf[32];
 562         char    *p, *end;
 563
 564         logmsg(LL_TRACE, "revoking kernel key %08x\n", keyid);
 565
 566         p = buf;
 567         end = buf + sizeof(buf);
 568
 569         WRITE_BYTES(&p, end, seqwin);
 570         WRITE_BYTES(&p, end, rpc_error);
 571         WRITE_BYTES(&p, end, gss_error);
 572
 573 again:
 574         if (keyctl_update(keyid, buf, p - buf)) {
 575                 if (errno != EAGAIN) {
 576                         logmsg(LL_ERR, "revoke key %08x: %s\n",
 577                                keyid, strerror(errno));
 578                         return -1;
 579                 }
 580
 581                 logmsg(LL_WARN, "key %08x: revoking too soon, try again\n",
 582                        keyid);
 583                 sleep(2);
 584                 goto again;
 585         }
 586
 587         logmsg(LL_INFO, "key %08x: revoked\n", keyid);
 588         return 0;
 589 }
 590
 591 static
 592 int update_kernel_key(key_serial_t keyid,
 593                       struct lgss_nego_data *lnd,
 594                       gss_buffer_desc *ctx_token)
 595 {
 596         char        *buf = NULL, *p = NULL, *end = NULL;
 597         unsigned int buf_size = 0;
 598         int          rc;
 599
 600         logmsg(LL_TRACE, "updating kernel key %08x\n", keyid);
 601
 602         buf_size = sizeof(lnd->lnd_seq_win) +
 603                    sizeof(lnd->lnd_rmt_ctx.length) + lnd->lnd_rmt_ctx.length +
 604                    sizeof(ctx_token->length) + ctx_token->length;
 605         buf = malloc(buf_size);
 606         if (buf == NULL) {
 607                 logmsg(LL_ERR, "key %08x: can't alloc update buf: size %d\n",
 608                        keyid, buf_size);
 609                 return 1;
 610         }
 611
 612         p = buf;
 613         end = buf + buf_size;
 614         rc = -1;
 615
 616         if (WRITE_BYTES(&p, end, lnd->lnd_seq_win))
 617                 goto out;
 618         if (write_buffer(&p, end, &lnd->lnd_rmt_ctx))
 619                 goto out;
 620         if (write_buffer(&p, end, ctx_token))
 621                 goto out;
 622
 623 again:
 624         if (keyctl_update(keyid, buf, p - buf)) {
 625                 if (errno != EAGAIN) {
 626                         logmsg(LL_ERR, "update key %08x: %s\n",
 627                                keyid, strerror(errno));
 628                         goto out;
 629                 }
 630
 631                 logmsg(LL_DEBUG, "key %08x: updating too soon, try again\n",
 632                        keyid);
 633                 sleep(2);
 634                 goto again;
 635         }
 636
 637         rc = 0;
 638         logmsg(LL_DEBUG, "key %08x: updated\n", keyid);
 639 out:
 640         free(buf);
 641         return rc;
 642 }
 643
 644 static int lgssc_kr_negotiate_krb(key_serial_t keyid, struct lgss_cred *cred,
 645                                   struct keyring_upcall_param *kup,
 646                                   int req_fd[2], int reply_fd[2])
 647 {
 648         struct lgss_nego_data lnd;
 649         OM_uint32 min_stat;
 650         int rc = -1;
 651         bool redo = true;
 652
 653         if (lgss_get_service_str(&g_service, kup->kup_svc, kup->kup_nid)) {
 654                 logmsg(LL_ERR, "key %08x: failed to construct service "
 655                        "string\n", keyid);
 656                 error_kernel_key(keyid, -EACCES, 0);
 657                 goto out_cred;
 658         }
 659
 660         if (lgss_using_cred(cred)) {
 661                 logmsg(LL_ERR, "key %08x: can't using cred\n", keyid);
 662                 error_kernel_key(keyid, -EACCES, 0);
 663                 goto out_cred;
 664         }
 665
 666 retry_nego:
 667         memset(&lnd, 0, sizeof(lnd));
 668         if (lgssc_init_nego_data(&lnd, kup, cred->lc_mech->lmt_mech_n)) {
 669                 logmsg(LL_ERR, "key %08x: failed to initialize "
 670                        "negotiation data\n", keyid);
 671                 error_kernel_key(keyid, lnd.lnd_rpc_err, lnd.lnd_gss_err);
 672                 goto out_cred;
 673         }
 674
 675         rc = lgssc_negotiation(&lnd, req_fd, reply_fd);
 676         if (rc == -EAGAIN || (rc == -ETIMEDOUT && redo)) {
 677                 logmsg(LL_ERR, "Failed negotiation must retry\n");
 678                 redo = false;
 679                 goto retry_nego;
 680         } else if (rc) {
 681                 logmsg(LL_ERR, "key %08x: failed to negotiation\n", keyid);
 682                 error_kernel_key(keyid, lnd.lnd_rpc_err, lnd.lnd_gss_err);
 683                 goto out;
 684         }
 685
 686         rc = serialize_context_for_kernel(lnd.lnd_ctx, &lnd.lnd_ctx_token,
 687                                           lnd.lnd_mech);
 688         if (rc) {
 689                 logmsg(LL_ERR, "key %08x: failed to export context\n", keyid);
 690                 error_kernel_key(keyid, rc, lnd.lnd_gss_err);
 691                 goto out;
 692         }
 693
 694         rc = update_kernel_key(keyid,  &lnd, &lnd.lnd_ctx_token);
 695         if (rc)
 696                 goto out;
 697
 698         rc = 0;
 699         logmsg(LL_INFO, "key %08x for user %u is updated OK!\n",
 700                keyid, kup->kup_uid);
 701 out:
 702         if (lnd.lnd_ctx_token.length != 0)
 703                 gss_release_buffer(&min_stat, &lnd.lnd_ctx_token);
 704
 705         lgssc_fini_nego_data(&lnd);
 706
 707 out_cred:
 708         lgss_release_cred(cred);
 709         return rc;
 710 }
 711
 712 static int lgssc_kr_negotiate_manual(key_serial_t keyid, struct lgss_cred *cred,
 713                                      struct keyring_upcall_param *kup,
 714                                      int req_fd[2], int reply_fd[2])
 715 {
 716         struct lgss_nego_data lnd;
 717         OM_uint32 min_stat;
 718         int rc;
 719         bool redo = true;
 720
 721         rc = lgss_get_service_str(&g_service, kup->kup_svc, kup->kup_nid);
 722         if (rc) {
 723                 logmsg(LL_ERR, "key %08x: failed to construct service "
 724                        "string\n", keyid);
 725                 error_kernel_key(keyid, -EACCES, 0);
 726                 goto out_cred;
 727         }
 728
 729         rc = lgss_using_cred(cred);
 730         if (rc) {
 731                 logmsg(LL_ERR, "key %08x: can't use cred\n", keyid);
 732                 error_kernel_key(keyid, -EACCES, 0);
 733                 goto out_cred;
 734         }
 735
 736 retry:
 737         memset(&lnd, 0, sizeof(lnd));
 738         rc = lgssc_init_nego_data(&lnd, kup, cred->lc_mech->lmt_mech_n);
 739         if (rc) {
 740                 logmsg(LL_ERR, "key %08x: failed to initialize "
 741                        "negotiation data\n", keyid);
 742                 error_kernel_key(keyid, lnd.lnd_rpc_err, lnd.lnd_gss_err);
 743                 goto out_cred;
 744         }
 745
 746         /*
 747          * Handles the negotiation but then calls lgss_validate to make sure
 748          * the token is valid.  It also populates the lnd_ctx_token for the
 749          * update to the kernel key
 750          */
 751         rc = lgssc_negotiation_manual(&lnd, cred, req_fd, reply_fd);
 752         if (rc == -EAGAIN || (rc == -ETIMEDOUT && redo)) {
 753                 logmsg(LL_ERR, "Failed negotiation must retry\n");
 754                 redo = false;
 755                 goto retry;
 756         } else if (rc) {
 757                 logmsg(LL_ERR, "key %08x: failed to negotiate\n", keyid);
 758                 error_kernel_key(keyid, lnd.lnd_rpc_err, lnd.lnd_gss_err);
 759                 goto out;
 760         }
 761
 762         rc = update_kernel_key(keyid,  &lnd, &lnd.lnd_ctx_token);
 763         if (rc)
 764                 goto out;
 765
 766         logmsg(LL_INFO, "key %08x for user %u is updated OK!\n",
 767                keyid, kup->kup_uid);
 768 out:
 769         if (lnd.lnd_ctx_token.length != 0)
 770                 gss_release_buffer(&min_stat, &lnd.lnd_ctx_token);
 771
 772         lgssc_fini_nego_data(&lnd);
 773
 774 out_cred:
 775         lgss_release_cred(cred);
 776         return rc;
 777 }
 778
 779 /*
 780  * note we inherited assumed authority from parent process
 781  */
 782 static int lgssc_kr_negotiate(key_serial_t keyid, struct lgss_cred *cred,
 783                               struct keyring_upcall_param *kup,
 784                               int req_fd[2], int reply_fd[2])
 785 {
 786         int rc;
 787
 788         logmsg(LL_TRACE, "child start on behalf of key %08x: "
 789                "cred %p, uid %u, svc %u, nid %"PRIx64", uids: %u:%u/%u:%u\n",
 790                keyid, cred, cred->lc_uid, cred->lc_tgt_svc, cred->lc_tgt_nid,
 791                kup->kup_uid, kup->kup_gid, kup->kup_fsuid, kup->kup_fsgid);
 792
 793         switch (cred->lc_mech->lmt_mech_n) {
 794         case LGSS_MECH_NULL:
 795         case LGSS_MECH_SK:
 796                 rc = lgssc_kr_negotiate_manual(keyid, cred, kup,
 797                                                req_fd, reply_fd);
 798                 break;
 799         case LGSS_MECH_KRB5:
 800         default:
 801                 rc = lgssc_kr_negotiate_krb(keyid, cred, kup, req_fd, reply_fd);
 802                 break;
 803         }
 804
 805         return rc;
 806 }
 807
 808 /*
 809  * call out info format: s[:s]...
 810  *  [0]: secid          (uint)
 811  *  [1]: mech_name      (string)
 812  *  [2]: uid            (uint)
 813  *  [3]: gid            (uint)
 814  *  [4]: flags          (string) FMT: r-root; m-mdt; o-ost
 815  *  [5]: svc type       (char)
 816  *  [6]: lustre_svc     (int)
 817  *  [7]: target_nid     (uint64)
 818  *  [8]: target_uuid    (string)
 819  *  [9]: self_nid        (uint64)
 820  *  [10]: pid            (uint)
 821  */
 822 static int parse_callout_info(const char *coinfo,
 823                               struct keyring_upcall_param *uparam)
 824 {
 825         const int       nargs = 11;
 826         char            buf[1024];
 827         char           *string = buf;
 828         int             length, i;
 829         char           *data[nargs];
 830         char           *pos;
 831
 832         length = strlen(coinfo) + 1;
 833         if (length > 1024) {
 834                 logmsg(LL_ERR, "coinfo too long\n");
 835                 return -1;
 836         }
 837         memcpy(buf, coinfo, length);
 838
 839         for (i = 0; i < nargs - 1; i++) {
 840                 pos = strchr(string, ':');
 841                 if (pos == NULL) {
 842                         logmsg(LL_ERR, "short of components\n");
 843                         return -1;
 844                 }
 845
 846                 *pos = '\0';
 847                 data[i] = string;
 848                 string = pos + 1;
 849         }
 850         data[i] = string;
 851
 852         logmsg(LL_TRACE, "components: %s,%s,%s,%s,%s,%c,%s,%s,%s,%s,%s\n",
 853                data[0], data[1], data[2], data[3], data[4], data[5][0],
 854                data[6], data[7], data[8], data[9], data[10]);
 855
 856         uparam->kup_secid = strtol(data[0], NULL, 0);
 857         snprintf(uparam->kup_mech, sizeof(uparam->kup_mech), "%s", data[1]);
 858         uparam->kup_uid = strtol(data[2], NULL, 0);
 859         uparam->kup_gid = strtol(data[3], NULL, 0);
 860         if (strchr(data[4], 'r'))
 861                 uparam->kup_is_root = 1;
 862         if (strchr(data[4], 'm'))
 863                 uparam->kup_is_mdt = 1;
 864         if (strchr(data[4], 'o'))
 865                 uparam->kup_is_ost = 1;
 866         uparam->kup_svc_type = data[5][0];
 867         uparam->kup_svc = strtol(data[6], NULL, 0);
 868         uparam->kup_nid = strtoll(data[7], NULL, 0);
 869         snprintf(uparam->kup_tgt, sizeof(uparam->kup_tgt), "%s", data[8]);
 870         uparam->kup_selfnid = strtoll(data[9], NULL, 0);
 871         uparam->kup_pid = strtol(data[10], NULL, 0);
 872
 873         logmsg(LL_DEBUG, "parse call out info: secid %d, mech %s, ugid %u:%u, "
 874                "is_root %d, is_mdt %d, is_ost %d, svc type %c, svc %d, "
 875                "nid 0x%"PRIx64", tgt %s, self nid 0x%"PRIx64", pid %d\n",
 876                uparam->kup_secid, uparam->kup_mech,
 877                uparam->kup_uid, uparam->kup_gid,
 878                uparam->kup_is_root, uparam->kup_is_mdt, uparam->kup_is_ost,
 879                uparam->kup_svc_type, uparam->kup_svc, uparam->kup_nid,
 880                uparam->kup_tgt, uparam->kup_selfnid, uparam->kup_pid);
 881         return 0;
 882 }
 883
 884 static void set_log_level()
 885 {
 886         unsigned int level;
 887         glob_t path;
 888         FILE *file;
 889
 890         if (cfs_get_param_paths(&path,
 891                                 "sptlrpc/gss/lgss_keyring/debug_level") != 0)
 892                 return;
 893         file = fopen(path.gl_pathv[0], "r");
 894         if (file == NULL) {
 895                 cfs_free_param_data(&path);
 896                 return;
 897         }
 898
 899         if (fscanf(file, "%u", &level) != 1)
 900                 goto out;
 901
 902         if (level >= LL_MAX)
 903                 goto out;
 904
 905         lgss_set_loglevel(level);
 906 out:
 907         cfs_free_param_data(&path);
 908         fclose(file);
 909 }
 910
 911 static int associate_with_ns(char *path)
 912 {
 913         int fd, rc = -1;
 914
 915         fd = open(path, O_RDONLY);
 916         if (fd != -1) {
 917                 rc = setns(fd, 0);
 918                 close(fd);
 919         }
 920
 921         return rc;
 922 }
 923
 924 static int prepare_and_instantiate(struct lgss_cred *cred, key_serial_t keyid,
 925                                    uint32_t uid)
 926 {
 927         key_serial_t inst_keyring;
 928
 929         if (lgss_prepare_cred(cred)) {
 930                 logmsg(LL_ERR, "key %08x: failed to prepare credentials "
 931                        "for user %d\n", keyid, uid);
 932                 return 1;
 933         }
 934
 935         /* pre initialize the key. note the keyring linked to is actually of the
 936          * original requesting process, not _this_ upcall process. if it's for
 937          * root user, don't link to any keyrings because we want fully control
 938          * on it, and share it among all root sessions; otherswise link to
 939          * session keyring.
 940          */
 941         if (cred->lc_root_flags != 0)
 942                 inst_keyring = 0;
 943         else
 944                 inst_keyring = KEY_SPEC_SESSION_KEYRING;
 945
 946         if (keyctl_instantiate(keyid, NULL, 0, inst_keyring)) {
 947                 logmsg(LL_ERR, "instantiate key %08x in keyring id %d: %s\n",
 948                        keyid, inst_keyring, strerror(errno));
 949                 return 1;
 950         }
 951
 952         logmsg(LL_TRACE, "instantiated kernel key %08x in keyring id %d\n",
 953                keyid, inst_keyring);
 954
 955         return 0;
 956 }
 957
 958 /****************************************
 959  * main process                         *
 960  ****************************************/
 961
 962 int main(int argc, char *argv[])
 963 {
 964         struct keyring_upcall_param uparam;
 965         key_serial_t keyid;
 966         key_serial_t sring;
 967         pid_t child;
 968         int req_fd[2] = { -1, -1 };
 969         int reply_fd[2] = { -1, -1 };
 970         struct lgss_mech_type *mech;
 971         struct lgss_cred *cred;
 972         char path[PATH_MAX] = "";
 973         int other_ns = 0;
 974         int rc = 0, opt;
 975         struct stat parent_ns = { .st_ino = 0 };
 976         struct stat caller_ns = { .st_ino = 0 };
 977
 978         static struct option long_opts[] = {
 979                 { .name = "realm", .has_arg = required_argument, .val = 'R'},
 980                 { .name = NULL, } };
 981
 982         set_log_level();
 983
 984         logmsg(LL_TRACE, "start parsing parameters\n");
 985
 986         /* one possible option before upcall parameters: -R REALM */
 987         while ((opt = getopt_long(argc, argv, "R:", long_opts, NULL)) != EOF) {
 988                 switch (opt) {
 989                 case 'R':
 990                         lgss_client_realm = optarg;
 991                         break;
 992                 default:
 993                         logmsg(LL_ERR, "invalid parameter %s\n",
 994                                argv[optind - 1]);
 995                         return 1;
 996                 }
 997         }
 998
 999         if (lgss_client_realm) {
1000                 /* shift args to meet expected upcall parameters */
1001                 argc -= optind - 1;
1002                 argv += optind - 1;
1003         }
1004
1005         /*
1006          * parse & sanity check upcall parameters
1007          * expected to be called with:
1008          * [1]:  operation
1009          * [2]:  key ID
1010          * [3]:  key type
1011          * [4]:  key description
1012          * [5]:  call out info
1013          * [6]:  UID
1014          * [7]:  GID
1015          * [8]:  thread keyring
1016          * [9]:  process keyring
1017          * [10]: session keyring
1018          */
1019         if (argc != 10 + 1) {
1020                 logmsg(LL_ERR, "invalid parameter number %d\n", argc);
1021                 return 1;
1022         }
1023
1024         memset(&uparam, 0, sizeof(uparam));
1025
1026         if (strcmp(argv[1], "create") != 0) {
1027                 logmsg(LL_ERR,
1028                        "invalid OP %s (key %s, desc %s, ugid %s:%s, sring %s, coinfo %s)\n",
1029                        argv[1], argv[2], argv[4], argv[6], argv[7], argv[10],
1030                        argv[5]);
1031                 return 1;
1032         }
1033
1034         if (sscanf(argv[2], "%d", &keyid) != 1) {
1035                 logmsg(LL_ERR,
1036                        "can't extract KeyID: %s (key %s, desc %s, ugid %s:%s, sring %s, coinfo %s)\n",
1037                        argv[2], argv[2], argv[4], argv[6], argv[7], argv[10],
1038                        argv[5]);
1039                 return 1;
1040         }
1041
1042         logmsg(LL_INFO, "key %08x, desc %s, ugid %s:%s, sring %s, coinfo %s\n",
1043                keyid, argv[4], argv[6], argv[7], argv[10], argv[5]);
1044
1045         if (sscanf(argv[6], "%d", &uparam.kup_fsuid) != 1) {
1046                 logmsg(LL_ERR, "can't extract UID: %s\n", argv[6]);
1047                 return 1;
1048         }
1049
1050         if (sscanf(argv[7], "%d", &uparam.kup_fsgid) != 1) {
1051                 logmsg(LL_ERR, "can't extract GID: %s\n", argv[7]);
1052                 return 1;
1053         }
1054
1055         if (sscanf(argv[10], "%d", &sring) != 1) {
1056                 logmsg(LL_ERR, "can't extract session keyring: %s\n", argv[10]);
1057                 return 1;
1058         }
1059
1060         if (parse_callout_info(argv[5], &uparam)) {
1061                 logmsg(LL_ERR, "can't extract callout info: %s\n", argv[5]);
1062                 return 1;
1063         }
1064
1065         logmsg(LL_TRACE, "parsing parameters OK\n");
1066
1067         /*
1068          * prepare a cred
1069          */
1070         mech = lgss_name2mech(uparam.kup_mech);
1071         if (mech == NULL) {
1072                 logmsg(LL_ERR, "key %08x: unsupported mech: %s\n",
1073                        keyid, uparam.kup_mech);
1074                 return 1;
1075         }
1076
1077         if (lgss_mech_initialize(mech)) {
1078                 logmsg(LL_ERR, "key %08x: can't initialize mech %s\n",
1079                        keyid, mech->lmt_name);
1080                 return 1;
1081         }
1082
1083         cred = lgss_create_cred(mech);
1084         if (cred == NULL) {
1085                 logmsg(LL_ERR, "key %08x: can't create a new %s cred\n",
1086                        keyid, mech->lmt_name);
1087                 return 1;
1088         }
1089
1090         cred->lc_uid = uparam.kup_uid;
1091         cred->lc_root_flags |= uparam.kup_is_root ? LGSS_ROOT_CRED_ROOT : 0;
1092         cred->lc_root_flags |= uparam.kup_is_mdt ? LGSS_ROOT_CRED_MDT : 0;
1093         cred->lc_root_flags |= uparam.kup_is_ost ? LGSS_ROOT_CRED_OST : 0;
1094         cred->lc_tgt_nid = uparam.kup_nid;
1095         cred->lc_tgt_svc = uparam.kup_svc;
1096         cred->lc_tgt_uuid = uparam.kup_tgt;
1097         cred->lc_svc_type = uparam.kup_svc_type;
1098         cred->lc_self_nid = uparam.kup_selfnid;
1099
1100         /* Is caller in different namespace? */
1101         /* If passed caller's pid is 0, it means we have to stick
1102          * with current namespace.
1103          */
1104         if (uparam.kup_pid) {
1105                 snprintf(path, sizeof(path), "/proc/%d/ns/mnt", getpid());
1106                 if (stat(path, &parent_ns)) {
1107                         logmsg(LL_DEBUG, "cannot stat %s: %s\n",
1108                                path, strerror(errno));
1109                 } else {
1110                         snprintf(path, sizeof(path), "/proc/%d/ns/mnt",
1111                                  uparam.kup_pid);
1112                         if (stat(path, &caller_ns))
1113                                 logmsg(LL_DEBUG, "cannot stat %s: %s\n",
1114                                        path, strerror(errno));
1115                         else if (caller_ns.st_ino != parent_ns.st_ino)
1116                                 other_ns = 1;
1117                 }
1118         }
1119
1120         /*
1121          * if caller's namespace is different, fork a child and associate it
1122          * with caller's namespace to do credentials preparation
1123          */
1124         if (other_ns) {
1125                 logmsg(LL_TRACE, "caller's namespace is different\n");
1126
1127                 /* use pipes to pass info between child and parent processes */
1128                 if (pipe(req_fd) == -1) {
1129                         logmsg(LL_ERR, "key %08x: pipe failed: %s\n",
1130                                keyid, strerror(errno));
1131                         return 1;
1132                 }
1133                 if (pipe(reply_fd) == -1) {
1134                         logmsg(LL_ERR, "key %08x: pipe failed: %s\n",
1135                                keyid, strerror(errno));
1136                         return 1;
1137                 }
1138
1139                 child = fork();
1140                 if (child == -1) {
1141                         logmsg(LL_ERR, "key %08x: can't create child: %s\n",
1142                                keyid, strerror(errno));
1143                         rc = 1;
1144                         goto out_pipe;
1145                 } else if (child == 0) {
1146                         int rc2;
1147                         /* child process: carry out credentials preparation
1148                          * in caller's namespace */
1149
1150                         close(req_fd[0]); /* close unsed read end */
1151                         req_fd[0] = -1;
1152                         close(reply_fd[1]); /* close unsed write end */
1153                         reply_fd[1] = -1;
1154
1155                         if (associate_with_ns(path) != 0) {
1156                                 logmsg(LL_ERR,
1157                                        "failed to attach to pid %d namespace: "
1158                                        "%s\n", uparam.kup_pid, strerror(errno));
1159                                 rc = 1;
1160                                 goto out_pipe;
1161                         }
1162                         logmsg(LL_TRACE, "working in namespace of pid %d\n",
1163                                uparam.kup_pid);
1164
1165                         rc = prepare_and_instantiate(cred, keyid,
1166                                                      uparam.kup_uid);
1167
1168                         /* send to parent the status of credentials preparation
1169                          * and key instantiation */
1170                         rc2 = send_to(req_fd[1], &rc, sizeof(rc));
1171                         rc = (rc == 0 ? rc2 : rc);
1172                         if (rc != 0)
1173                                 goto out_pipe;
1174
1175                         /* now do real gss negotiation
1176                          * parent main process will not wait for us,
1177                          * as it has to be done in the background */
1178                         rc = lgssc_kr_negotiate(keyid, cred, &uparam,
1179                                                 req_fd, reply_fd);
1180                         goto out_pipe;
1181                 } else {
1182                         int rc2;
1183                         /* parent process: exchange info with child carrying out
1184                          * credentials preparation */
1185
1186                         close(req_fd[1]); /* close unsed write end */
1187                         req_fd[1] = -1;
1188                         close(reply_fd[0]); /* close unsed read end */
1189                         reply_fd[0] = -1;
1190
1191                         /* get status of credentials preparation
1192                          * and key instantiation */
1193                         rc2 = receive_from(req_fd[0], &rc, sizeof(rc));
1194                         if (rc2 != 0 || rc != 0) {
1195                                 logmsg(LL_ERR, "child failed preparing creds: "
1196                                        "%s\n",
1197                                        rc2 != 0 ? strerror(-rc2)
1198                                                 : strerror(rc));
1199                                 goto out_pipe;
1200                         }
1201
1202                         /*
1203                          * fork a child here to participate in gss negotiation,
1204                          * as it has to be done in the background
1205                          */
1206                         child = fork();
1207                         if (child == -1) {
1208                                 logmsg(LL_ERR,
1209                                        "key %08x: can't create child: %s\n",
1210                                        keyid, strerror(errno));
1211                                 rc = 1;
1212                                 goto out_pipe;
1213                         } else if (child == 0) {
1214                                 struct lgssd_ioctl_param param;
1215                                 char outbuf[8192] = { 0 };
1216                                 void *gss_token = NULL;
1217
1218                                 /* get ioctl buffer from child */
1219                                 rc = receive_from(req_fd[0], &param,
1220                                                   sizeof(param));
1221                                 if (rc != 0)
1222                                         goto out_pipe;
1223
1224                                 gss_token = calloc(1, param.send_token_size);
1225                                 if (gss_token == NULL)
1226                                         goto out_pipe;
1227
1228                                 /* get gss token from child */
1229                                 rc = receive_from(req_fd[0], gss_token,
1230                                                   param.send_token_size);
1231                                 if (rc != 0)
1232                                         goto out_token;
1233
1234                                 param.send_token = (char *)gss_token;
1235                                 param.reply_buf_size = sizeof(outbuf);
1236                                 param.reply_buf = outbuf;
1237
1238                                 /* do ioctl in place of child process carrying
1239                                  * out credentials negotiation: as it runs in
1240                                  * a container, it might not be able to
1241                                  * perform ioctl */
1242                                 rc = gss_do_ioctl(&param);
1243                                 if (rc != 0)
1244                                         goto out_token;
1245
1246                                 /* send ioctl status to child */
1247                                 rc = send_to(reply_fd[1], &param.status,
1248                                              sizeof(param.status));
1249                                 if (rc != 0)
1250                                         goto out_token;
1251                                 /* send reply buffer to child */
1252                                 rc = send_to(reply_fd[1], outbuf,
1253                                              sizeof(outbuf));
1254                                 if (rc != 0)
1255                                         goto out_token;
1256
1257 out_token:
1258                                 free(gss_token);
1259                                 goto out_pipe;
1260                         }
1261
1262                         logmsg(LL_TRACE, "forked child %d\n", child);
1263                 }
1264 out_pipe:
1265                 close(req_fd[0]);
1266                 close(req_fd[1]);
1267                 close(reply_fd[0]);
1268                 close(reply_fd[1]);
1269                 lgss_fini(cred);
1270                 return rc;
1271         } else {
1272                 if (uparam.kup_pid)
1273                         logmsg(LL_TRACE, "caller's namespace is the same\n");
1274                 else
1275                         logmsg(LL_TRACE, "stick with current namespace\n");
1276
1277                 rc = prepare_and_instantiate(cred, keyid, uparam.kup_uid);
1278                 if (rc != 0)
1279                         goto out_reg;
1280
1281                 /*
1282                  * fork a child to do the real gss negotiation
1283                  */
1284                 child = fork();
1285                 if (child == -1) {
1286                         logmsg(LL_ERR, "key %08x: can't create child: %s\n",
1287                                keyid, strerror(errno));
1288                         rc = 1;
1289                         goto out_reg;
1290                 } else if (child == 0) {
1291                         rc = lgssc_kr_negotiate(keyid, cred, &uparam,
1292                                                 req_fd, reply_fd);
1293                         goto out_reg;
1294                 } else {
1295                         logmsg(LL_TRACE, "forked child %d\n", child);
1296                         return rc;
1297                 }
1298
1299 out_reg:
1300                 lgss_fini(cred);
1301                 return rc;
1302         }
1303 }