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.sun.com/software/products/lustre/docs/GPLv2.pdf
  19  *
  20  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  21  * CA 95054 USA or visit www.sun.com if you need additional information or
  22  * have any questions.
  23  *
  24  * GPL HEADER END
  25  */
  26 /*
  27  * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved.
  28  * Use is subject to license terms.
  29  *
  30  * Copyright (c) 2011, 2014, Intel Corporation.
  31  */
  32 /*
  33  * This file is part of Lustre, http://www.lustre.org/
  34  * Lustre is a trademark of Sun Microsystems, Inc.
  35  *
  36  * lustre/utils/gss/lgss_keyring.c
  37  *
  38  * user-space upcall to create GSS context, using keyring interface to kernel
  39  *
  40  * Author: Eric Mei <ericm@clusterfs.com>
  41  */
  42
  43 #include <unistd.h>
  44 #include <stdlib.h>
  45 #include <stdio.h>
  46 #include <fcntl.h>
  47 #include <inttypes.h>
  48 #include <string.h>
  49 #include <errno.h>
  50 #include <pwd.h>
  51 #include <keyutils.h>
  52 #include <gssapi/gssapi.h>
  53
  54 #include <libcfs/util/string.h>
  55 #include "lsupport.h"
  56 #include "lgss_utils.h"
  57 #include "write_bytes.h"
  58 #include "context.h"
  59
  60 /*
  61  * gss target string of lustre service we are negotiating for
  62  */
  63 static char *g_service = NULL;
  64
  65 /*
  66  * all data about negotiation
  67  */
  68 struct lgss_nego_data {
  69         uint32_t        lnd_established:1;
  70
  71         int             lnd_secid;
  72         uint32_t        lnd_uid;
  73         uint32_t        lnd_lsvc;
  74         char           *lnd_uuid;
  75
  76         gss_OID         lnd_mech;               /* mech OID */
  77         gss_name_t      lnd_svc_name;           /* service name */
  78         unsigned int    lnd_req_flags;          /* request flags */
  79         gss_cred_id_t   lnd_cred;               /* credential */
  80         gss_ctx_id_t    lnd_ctx;                /* session context */
  81         gss_buffer_desc lnd_rmt_ctx;            /* remote handle of context */
  82         uint32_t        lnd_seq_win;            /* sequence window */
  83
  84         int             lnd_rpc_err;
  85         int             lnd_gss_err;
  86 };
  87
  88 /*
  89  * context creation response
  90  */
  91 struct lgss_init_res {
  92         gss_buffer_desc gr_ctx;         /* context handle */
  93         unsigned int    gr_major;       /* major status */
  94         unsigned int    gr_minor;       /* minor status */
  95         unsigned int    gr_win;         /* sequence window */
  96         gss_buffer_desc gr_token;       /* token */
  97 };
  98
  99 struct keyring_upcall_param {
 100         uint32_t        kup_ver;
 101         uint32_t        kup_secid;
 102         uint32_t        kup_uid;
 103         uint32_t        kup_fsuid;
 104         uint32_t        kup_gid;
 105         uint32_t        kup_fsgid;
 106         uint32_t        kup_svc;
 107         uint64_t        kup_nid;
 108         uint64_t        kup_selfnid;
 109         char            kup_tgt[64];
 110         char            kup_mech[16];
 111         unsigned int    kup_is_root:1,
 112                         kup_is_mdt:1,
 113                         kup_is_ost:1;
 114 };
 115
 116 /****************************************
 117  * child process: gss negotiation       *
 118  ****************************************/
 119
 120 #define INIT_CHANNEL    "/proc/fs/lustre/sptlrpc/gss/init_channel"
 121
 122 int do_nego_rpc(struct lgss_nego_data *lnd,
 123                 gss_buffer_desc *gss_token,
 124                 struct lgss_init_res *gr)
 125 {
 126         struct lgssd_ioctl_param  param;
 127         struct passwd            *pw;
 128         int                       fd, ret, res;
 129         char                      outbuf[8192];
 130         unsigned int             *p;
 131
 132         logmsg(LL_TRACE, "start negotiation rpc\n");
 133
 134         pw = getpwuid(lnd->lnd_uid);
 135         if (!pw) {
 136                 logmsg(LL_ERR, "no uid %u in local user database\n",
 137                        lnd->lnd_uid);
 138                 return -EACCES;
 139         }
 140
 141         param.version = GSSD_INTERFACE_VERSION;
 142         param.secid = lnd->lnd_secid;
 143         param.uuid = lnd->lnd_uuid;
 144         param.lustre_svc = lnd->lnd_lsvc;
 145         param.uid = lnd->lnd_uid;
 146         param.gid = pw->pw_gid;
 147         param.send_token_size = gss_token->length;
 148         param.send_token = (char *) gss_token->value;
 149         param.reply_buf_size = sizeof(outbuf);
 150         param.reply_buf = outbuf;
 151
 152         logmsg(LL_TRACE, "to open " INIT_CHANNEL "\n");
 153
 154         fd = open(INIT_CHANNEL, O_WRONLY);
 155         if (fd < 0) {
 156                 logmsg(LL_ERR, "can't open " INIT_CHANNEL "\n");
 157                 return -EACCES;
 158         }
 159
 160         logmsg(LL_TRACE, "to down-write\n");
 161
 162         ret = write(fd, &param, sizeof(param));
 163         if (ret != sizeof(param)) {
 164                 logmsg(LL_ERR, "lustre ioctl err: %s\n", strerror(errno));
 165                 close(fd);
 166                 return -EACCES;
 167         }
 168         close(fd);
 169
 170         logmsg(LL_TRACE, "do_nego_rpc: to parse reply\n");
 171         if (param.status) {
 172                 logmsg(LL_ERR, "status: %ld (%s)\n",
 173                        param.status, strerror((int)param.status));
 174
 175                 /* kernel return -ETIMEDOUT means the rpc timedout, we should
 176                  * notify the caller to reinitiate the gss negotiation, by
 177                  * returning -ERESTART
 178                  */
 179                 if (param.status == -ETIMEDOUT)
 180                         return -ERESTART;
 181                 else
 182                         return param.status;
 183         }
 184
 185         p = (unsigned int *)outbuf;
 186         res = *p++;
 187         gr->gr_major = *p++;
 188         gr->gr_minor = *p++;
 189         gr->gr_win = *p++;
 190
 191         gr->gr_ctx.length = *p++;
 192         gr->gr_ctx.value = malloc(gr->gr_ctx.length);
 193         memcpy(gr->gr_ctx.value, p, gr->gr_ctx.length);
 194         p += (((gr->gr_ctx.length + 3) & ~3) / 4);
 195
 196         gr->gr_token.length = *p++;
 197         gr->gr_token.value = malloc(gr->gr_token.length);
 198         memcpy(gr->gr_token.value, p, gr->gr_token.length);
 199         p += (((gr->gr_token.length + 3) & ~3) / 4);
 200
 201         logmsg(LL_DEBUG, "do_nego_rpc: receive handle len %zu, token len %zu, "
 202                "res %d\n", gr->gr_ctx.length, gr->gr_token.length, res);
 203         return 0;
 204 }
 205
 206 /*
 207  * if return error, the lnd_rpc_err or lnd_gss_err is set.
 208  */
 209 static int lgssc_negotiation(struct lgss_nego_data *lnd)
 210 {
 211         struct lgss_init_res    gr;
 212         gss_buffer_desc        *recv_tokenp, send_token;
 213         OM_uint32               maj_stat, min_stat, ret_flags;
 214
 215         logmsg(LL_TRACE, "start gss negotiation\n");
 216
 217         /* GSS context establishment loop. */
 218         memset(&gr, 0, sizeof(gr));
 219         recv_tokenp = GSS_C_NO_BUFFER;
 220
 221         for (;;) {
 222                 maj_stat = gss_init_sec_context(&min_stat,
 223                                                 lnd->lnd_cred,
 224                                                 &lnd->lnd_ctx,
 225                                                 lnd->lnd_svc_name,
 226                                                 lnd->lnd_mech,
 227                                                 lnd->lnd_req_flags,
 228                                                 0,            /* time req */
 229                                                 NULL,         /* channel */
 230                                                 recv_tokenp,
 231                                                 NULL,         /* used mech */
 232                                                 &send_token,
 233                                                 &ret_flags,
 234                                                 NULL);        /* time rec */
 235
 236                 if (recv_tokenp != GSS_C_NO_BUFFER) {
 237                         gss_release_buffer(&min_stat, &gr.gr_token);
 238                         recv_tokenp = GSS_C_NO_BUFFER;
 239                 }
 240
 241                 if (maj_stat != GSS_S_COMPLETE &&
 242                     maj_stat != GSS_S_CONTINUE_NEEDED) {
 243                         lnd->lnd_gss_err = maj_stat;
 244
 245                         logmsg_gss(LL_ERR, lnd->lnd_mech, maj_stat, min_stat,
 246                                    "failed init context");
 247                         break;
 248                 }
 249
 250                 if (send_token.length != 0) {
 251                         memset(&gr, 0, sizeof(gr));
 252
 253                         lnd->lnd_rpc_err = do_nego_rpc(lnd, &send_token, &gr);
 254                         gss_release_buffer(&min_stat, &send_token);
 255
 256                         if (lnd->lnd_rpc_err) {
 257                                 logmsg(LL_ERR, "negotiation rpc error: %d\n",
 258                                        lnd->lnd_rpc_err);
 259                                 return -1;
 260                         }
 261
 262                         if (gr.gr_major != GSS_S_COMPLETE &&
 263                             gr.gr_major != GSS_S_CONTINUE_NEEDED) {
 264                                 lnd->lnd_gss_err = gr.gr_major;
 265
 266                                 logmsg(LL_ERR, "negotiation gss error %x\n",
 267                                        lnd->lnd_gss_err);
 268                                 return -1;
 269                         }
 270
 271                         if (gr.gr_ctx.length != 0) {
 272                                 if (lnd->lnd_rmt_ctx.value)
 273                                         gss_release_buffer(&min_stat,
 274                                                            &lnd->lnd_rmt_ctx);
 275                                 lnd->lnd_rmt_ctx = gr.gr_ctx;
 276                         }
 277
 278                         if (gr.gr_token.length != 0) {
 279                                 if (maj_stat != GSS_S_CONTINUE_NEEDED)
 280                                         break;
 281                                 recv_tokenp = &gr.gr_token;
 282                         }
 283                 }
 284
 285                 /* GSS_S_COMPLETE => check gss header verifier,
 286                  * usually checked in gss_validate
 287                  */
 288                 if (maj_stat == GSS_S_COMPLETE) {
 289                         lnd->lnd_established = 1;
 290                         lnd->lnd_seq_win = gr.gr_win;
 291                         break;
 292                 }
 293         }
 294
 295         /* End context negotiation loop. */
 296         if (!lnd->lnd_established) {
 297                 if (gr.gr_token.length != 0)
 298                         gss_release_buffer(&min_stat, &gr.gr_token);
 299
 300                 if (lnd->lnd_gss_err == GSS_S_COMPLETE)
 301                         lnd->lnd_rpc_err = -EACCES;
 302
 303                 logmsg(LL_ERR, "context negotiation failed\n");
 304                 return -1;
 305         }
 306
 307         logmsg(LL_DEBUG, "successfully negotiated a context\n");
 308         return 0;
 309 }
 310
 311 /*
 312  * if return error, the lnd_rpc_err or lnd_gss_err is set.
 313  */
 314 static int lgssc_init_nego_data(struct lgss_nego_data *lnd,
 315                                 struct keyring_upcall_param *kup,
 316                                 lgss_mech_t mech)
 317 {
 318         gss_buffer_desc         sname;
 319         OM_uint32               maj_stat, min_stat;
 320
 321         memset(lnd, 0, sizeof(*lnd));
 322
 323         lnd->lnd_secid = kup->kup_secid;
 324         lnd->lnd_uid = kup->kup_uid;
 325         lnd->lnd_lsvc = kup->kup_svc;
 326         lnd->lnd_uuid = kup->kup_tgt;
 327
 328         lnd->lnd_established = 0;
 329         lnd->lnd_svc_name = GSS_C_NO_NAME;
 330         lnd->lnd_cred = GSS_C_NO_CREDENTIAL;
 331         lnd->lnd_ctx = GSS_C_NO_CONTEXT;
 332         lnd->lnd_rmt_ctx = (gss_buffer_desc) GSS_C_EMPTY_BUFFER;
 333         lnd->lnd_seq_win = 0;
 334
 335         switch (mech) {
 336         case LGSS_MECH_KRB5:
 337                 lnd->lnd_mech = (gss_OID) &krb5oid;
 338                 lnd->lnd_req_flags = GSS_C_MUTUAL_FLAG;
 339                 break;
 340         default:
 341                 logmsg(LL_ERR, "invalid mech: %d\n", mech);
 342                 lnd->lnd_rpc_err = -EACCES;
 343                 return -1;
 344         }
 345
 346         sname.value = g_service;
 347         sname.length = strlen(g_service);
 348
 349         maj_stat = gss_import_name(&min_stat, &sname,
 350                                    (gss_OID) GSS_C_NT_HOSTBASED_SERVICE,
 351                                    &lnd->lnd_svc_name);
 352         if (maj_stat != GSS_S_COMPLETE) {
 353                 logmsg_gss(LL_ERR, lnd->lnd_mech, maj_stat, min_stat,
 354                            "can't import svc name");
 355                 lnd->lnd_gss_err = maj_stat;
 356                 return -1;
 357         }
 358
 359         return 0;
 360 }
 361
 362 void lgssc_fini_nego_data(struct lgss_nego_data *lnd)
 363 {
 364         OM_uint32       maj_stat, min_stat;
 365
 366         if (lnd->lnd_svc_name != GSS_C_NO_NAME) {
 367                 maj_stat = gss_release_name(&min_stat, &lnd->lnd_svc_name);
 368                 if (maj_stat != GSS_S_COMPLETE)
 369                         logmsg_gss(LL_ERR, lnd->lnd_mech, maj_stat, min_stat,
 370                                    "can't release service name");
 371         }
 372
 373         if (lnd->lnd_cred != GSS_C_NO_CREDENTIAL) {
 374                 maj_stat = gss_release_cred(&min_stat, &lnd->lnd_cred);
 375                 if (maj_stat != GSS_S_COMPLETE)
 376                         logmsg_gss(LL_ERR, lnd->lnd_mech, maj_stat, min_stat,
 377                                    "can't release credential");
 378         }
 379 }
 380
 381 static
 382 int error_kernel_key(key_serial_t keyid, int rpc_error, int gss_error)
 383 {
 384         int      seqwin = 0;
 385         char     buf[32];
 386         char    *p, *end;
 387
 388         logmsg(LL_TRACE, "revoking kernel key %08x\n", keyid);
 389
 390         p = buf;
 391         end = buf + sizeof(buf);
 392
 393         WRITE_BYTES(&p, end, seqwin);
 394         WRITE_BYTES(&p, end, rpc_error);
 395         WRITE_BYTES(&p, end, gss_error);
 396
 397 again:
 398         if (keyctl_update(keyid, buf, p - buf)) {
 399                 if (errno != EAGAIN) {
 400                         logmsg(LL_ERR, "revoke key %08x: %s\n",
 401                                keyid, strerror(errno));
 402                         return -1;
 403                 }
 404
 405                 logmsg(LL_WARN, "key %08x: revoking too soon, try again\n",
 406                        keyid);
 407                 sleep(2);
 408                 goto again;
 409         }
 410
 411         logmsg(LL_INFO, "key %08x: revoked\n", keyid);
 412         return 0;
 413 }
 414
 415 static
 416 int update_kernel_key(key_serial_t keyid,
 417                       struct lgss_nego_data *lnd,
 418                       gss_buffer_desc *ctx_token)
 419 {
 420         char        *buf = NULL, *p = NULL, *end = NULL;
 421         unsigned int buf_size = 0;
 422         int          rc;
 423
 424         logmsg(LL_TRACE, "updating kernel key %08x\n", keyid);
 425
 426         buf_size = sizeof(lnd->lnd_seq_win) +
 427                    sizeof(lnd->lnd_rmt_ctx.length) + lnd->lnd_rmt_ctx.length +
 428                    sizeof(ctx_token->length) + ctx_token->length;
 429         buf = malloc(buf_size);
 430         if (buf == NULL) {
 431                 logmsg(LL_ERR, "key %08x: can't alloc update buf: size %d\n",
 432                        keyid, buf_size);
 433                 return 1;
 434         }
 435
 436         p = buf;
 437         end = buf + buf_size;
 438         rc = -1;
 439
 440         if (WRITE_BYTES(&p, end, lnd->lnd_seq_win))
 441                 goto out;
 442         if (write_buffer(&p, end, &lnd->lnd_rmt_ctx))
 443                 goto out;
 444         if (write_buffer(&p, end, ctx_token))
 445                 goto out;
 446
 447 again:
 448         if (keyctl_update(keyid, buf, p - buf)) {
 449                 if (errno != EAGAIN) {
 450                         logmsg(LL_ERR, "update key %08x: %s\n",
 451                                keyid, strerror(errno));
 452                         goto out;
 453                 }
 454
 455                 logmsg(LL_DEBUG, "key %08x: updating too soon, try again\n",
 456                        keyid);
 457                 sleep(2);
 458                 goto again;
 459         }
 460
 461         rc = 0;
 462         logmsg(LL_DEBUG, "key %08x: updated\n", keyid);
 463 out:
 464         free(buf);
 465         return rc;
 466 }
 467
 468 /*
 469  * note we inherited assumed authority from parent process
 470  */
 471 static int lgssc_kr_negotiate(key_serial_t keyid, struct lgss_cred *cred,
 472                               struct keyring_upcall_param *kup)
 473 {
 474         struct lgss_nego_data   lnd;
 475         gss_buffer_desc         token = GSS_C_EMPTY_BUFFER;
 476         OM_uint32               min_stat;
 477         int                     rc = -1;
 478
 479         logmsg(LL_TRACE, "child start on behalf of key %08x: "
 480                "cred %p, uid %u, svc %u, nid %"PRIx64", uids: %u:%u/%u:%u\n",
 481                keyid, cred, cred->lc_uid, cred->lc_tgt_svc, cred->lc_tgt_nid,
 482                kup->kup_uid, kup->kup_gid, kup->kup_fsuid, kup->kup_fsgid);
 483
 484         if (lgss_get_service_str(&g_service, kup->kup_svc, kup->kup_nid)) {
 485                 logmsg(LL_ERR, "key %08x: failed to construct service "
 486                        "string\n", keyid);
 487                 error_kernel_key(keyid, -EACCES, 0);
 488                 goto out_cred;
 489         }
 490
 491         if (lgss_using_cred(cred)) {
 492                 logmsg(LL_ERR, "key %08x: can't using cred\n", keyid);
 493                 error_kernel_key(keyid, -EACCES, 0);
 494                 goto out_cred;
 495         }
 496
 497         if (lgssc_init_nego_data(&lnd, kup, cred->lc_mech->lmt_mech_n)) {
 498                 logmsg(LL_ERR, "key %08x: failed to initialize "
 499                        "negotiation data\n", keyid);
 500                 error_kernel_key(keyid, lnd.lnd_rpc_err, lnd.lnd_gss_err);
 501                 goto out_cred;
 502         }
 503
 504         rc = lgssc_negotiation(&lnd);
 505         if (rc) {
 506                 logmsg(LL_ERR, "key %08x: failed to negotiation\n", keyid);
 507                 error_kernel_key(keyid, lnd.lnd_rpc_err, lnd.lnd_gss_err);
 508                 goto out;
 509         }
 510
 511         rc = serialize_context_for_kernel(lnd.lnd_ctx, &token, lnd.lnd_mech);
 512         if (rc) {
 513                 logmsg(LL_ERR, "key %08x: failed to export context\n", keyid);
 514                 error_kernel_key(keyid, rc, lnd.lnd_gss_err);
 515                 goto out;
 516         }
 517
 518         rc = update_kernel_key(keyid,  &lnd, &token);
 519         if (rc)
 520                 goto out;
 521
 522         rc = 0;
 523         logmsg(LL_INFO, "key %08x for user %u is updated OK!\n",
 524                keyid, kup->kup_uid);
 525 out:
 526         if (token.length != 0)
 527                 gss_release_buffer(&min_stat, &token);
 528
 529         lgssc_fini_nego_data(&lnd);
 530
 531 out_cred:
 532         lgss_release_cred(cred);
 533         return rc;
 534 }
 535
 536 /*
 537  * call out info format: s[:s]...
 538  *  [0]: secid          (uint)
 539  *  [1]: mech_name      (string)
 540  *  [2]: uid            (uint)
 541  *  [3]: gid            (uint)
 542  *  [4]: flags          (string) FMT: r-root; m-mdt; o-ost
 543  *  [5]: lustre_svc     (uint)
 544  *  [6]: target_nid     (uint64)
 545  *  [7]: target_uuid    (string)
 546  *  [8]: self_nid        (uint64)
 547  */
 548 static int parse_callout_info(const char *coinfo,
 549                               struct keyring_upcall_param *uparam)
 550 {
 551         const int       nargs = 9;
 552         char            buf[1024];
 553         char           *string = buf;
 554         int             length, i;
 555         char           *data[nargs];
 556         char           *pos;
 557
 558         length = strlen(coinfo) + 1;
 559         if (length > 1024) {
 560                 logmsg(LL_ERR, "coinfo too long\n");
 561                 return -1;
 562         }
 563         memcpy(buf, coinfo, length);
 564
 565         for (i = 0; i < nargs - 1; i++) {
 566                 pos = strchr(string, ':');
 567                 if (pos == NULL) {
 568                         logmsg(LL_ERR, "short of components\n");
 569                         return -1;
 570                 }
 571
 572                 *pos = '\0';
 573                 data[i] = string;
 574                 string = pos + 1;
 575         }
 576         data[i] = string;
 577
 578         logmsg(LL_TRACE, "components: %s,%s,%s,%s,%s,%s,%s,%s,%s\n",
 579                data[0], data[1], data[2], data[3], data[4], data[5],
 580                data[6], data[7], data[8]);
 581
 582         uparam->kup_secid = strtol(data[0], NULL, 0);
 583         strlcpy(uparam->kup_mech, data[1], sizeof(uparam->kup_mech));
 584         uparam->kup_uid = strtol(data[2], NULL, 0);
 585         uparam->kup_gid = strtol(data[3], NULL, 0);
 586         if (strchr(data[4], 'r'))
 587                 uparam->kup_is_root = 1;
 588         if (strchr(data[4], 'm'))
 589                 uparam->kup_is_mdt = 1;
 590         if (strchr(data[4], 'o'))
 591                 uparam->kup_is_ost = 1;
 592         uparam->kup_svc = strtol(data[5], NULL, 0);
 593         uparam->kup_nid = strtoll(data[6], NULL, 0);
 594         strlcpy(uparam->kup_tgt, data[7], sizeof(uparam->kup_tgt));
 595         uparam->kup_selfnid = strtoll(data[8], NULL, 0);
 596
 597         logmsg(LL_DEBUG, "parse call out info: secid %d, mech %s, ugid %u:%u, "
 598                "is_root %d, is_mdt %d, is_ost %d, svc %d, nid 0x%"PRIx64", "
 599                "tgt %s, self nid 0x%"PRIx64"\n",
 600                uparam->kup_secid, uparam->kup_mech,
 601                uparam->kup_uid, uparam->kup_gid,
 602                uparam->kup_is_root, uparam->kup_is_mdt, uparam->kup_is_ost,
 603                uparam->kup_svc, uparam->kup_nid, uparam->kup_tgt,
 604                uparam->kup_selfnid);
 605         return 0;
 606 }
 607
 608 #define LOG_LEVEL_PATH  "/proc/fs/lustre/sptlrpc/gss/lgss_keyring/debug_level"
 609
 610 static void set_log_level()
 611 {
 612         FILE         *file;
 613         unsigned int  level;
 614
 615         file = fopen(LOG_LEVEL_PATH, "r");
 616         if (file == NULL)
 617                 return;
 618
 619         if (fscanf(file, "%u", &level) != 1)
 620                 goto out;
 621
 622         if (level >= LL_MAX)
 623                 goto out;
 624
 625         lgss_set_loglevel(level);
 626 out:
 627         fclose(file);
 628 }
 629
 630 /****************************************
 631  * main process                         *
 632  ****************************************/
 633
 634 int main(int argc, char *argv[])
 635 {
 636         struct keyring_upcall_param     uparam;
 637         key_serial_t                    keyid;
 638         key_serial_t                    sring;
 639         key_serial_t                    inst_keyring;
 640         pid_t                           child;
 641         struct lgss_mech_type          *mech;
 642         struct lgss_cred               *cred;
 643
 644         set_log_level();
 645
 646         logmsg(LL_TRACE, "start parsing parameters\n");
 647         /*
 648          * parse & sanity check upcall parameters
 649          * expected to be called with:
 650          * [1]:  operation
 651          * [2]:  key ID
 652          * [3]:  key type
 653          * [4]:  key description
 654          * [5]:  call out info
 655          * [6]:  UID
 656          * [7]:  GID
 657          * [8]:  thread keyring
 658          * [9]:  process keyring
 659          * [10]: session keyring
 660          */
 661         if (argc != 10 + 1) {
 662                 logmsg(LL_ERR, "invalid parameter number %d\n", argc);
 663                 return 1;
 664         }
 665
 666         logmsg(LL_INFO, "key %s, desc %s, ugid %s:%s, sring %s, coinfo %s\n",
 667                argv[2], argv[4], argv[6], argv[7], argv[10], argv[5]);
 668
 669         memset(&uparam, 0, sizeof(uparam));
 670
 671         if (strcmp(argv[1], "create") != 0) {
 672                 logmsg(LL_ERR, "invalid OP %s\n", argv[1]);
 673                 return 1;
 674         }
 675
 676         if (sscanf(argv[2], "%d", &keyid) != 1) {
 677                 logmsg(LL_ERR, "can't extract KeyID: %s\n", argv[2]);
 678                 return 1;
 679         }
 680
 681         if (sscanf(argv[6], "%d", &uparam.kup_fsuid) != 1) {
 682                 logmsg(LL_ERR, "can't extract UID: %s\n", argv[6]);
 683                 return 1;
 684         }
 685
 686         if (sscanf(argv[7], "%d", &uparam.kup_fsgid) != 1) {
 687                 logmsg(LL_ERR, "can't extract GID: %s\n", argv[7]);
 688                 return 1;
 689         }
 690
 691         if (sscanf(argv[10], "%d", &sring) != 1) {
 692                 logmsg(LL_ERR, "can't extract session keyring: %s\n", argv[10]);
 693                 return 1;
 694         }
 695
 696         if (parse_callout_info(argv[5], &uparam)) {
 697                 logmsg(LL_ERR, "can't extract callout info: %s\n", argv[5]);
 698                 return 1;
 699         }
 700
 701         logmsg(LL_TRACE, "parsing parameters OK\n");
 702
 703         /*
 704          * prepare a cred
 705          */
 706         mech = lgss_name2mech(uparam.kup_mech);
 707         if (mech == NULL) {
 708                 logmsg(LL_ERR, "key %08x: unsupported mech: %s\n",
 709                        keyid, uparam.kup_mech);
 710                 return 1;
 711         }
 712
 713         if (lgss_mech_initialize(mech)) {
 714                 logmsg(LL_ERR, "key %08x: can't initialize mech %s\n",
 715                        keyid, mech->lmt_name);
 716                 return 1;
 717         }
 718
 719         cred = lgss_create_cred(mech);
 720         if (cred == NULL) {
 721                 logmsg(LL_ERR, "key %08x: can't create a new %s cred\n",
 722                        keyid, mech->lmt_name);
 723                 return 1;
 724         }
 725
 726         cred->lc_uid = uparam.kup_uid;
 727         cred->lc_root_flags |= uparam.kup_is_root ? LGSS_ROOT_CRED_ROOT : 0;
 728         cred->lc_root_flags |= uparam.kup_is_mdt ? LGSS_ROOT_CRED_MDT : 0;
 729         cred->lc_root_flags |= uparam.kup_is_ost ? LGSS_ROOT_CRED_OST : 0;
 730         cred->lc_tgt_nid = uparam.kup_nid;
 731         cred->lc_tgt_svc = uparam.kup_svc;
 732         cred->lc_self_nid = uparam.kup_selfnid;
 733
 734         if (lgss_prepare_cred(cred)) {
 735                 logmsg(LL_ERR, "key %08x: failed to prepare credentials "
 736                        "for user %d\n", keyid, uparam.kup_uid);
 737                 return 1;
 738         }
 739
 740         /* pre initialize the key. note the keyring linked to is actually of the
 741          * original requesting process, not _this_ upcall process. if it's for
 742          * root user, don't link to any keyrings because we want fully control
 743          * on it, and share it among all root sessions; otherswise link to
 744          * session keyring.
 745          */
 746         if (cred->lc_root_flags != 0)
 747                 inst_keyring = 0;
 748         else
 749                 inst_keyring = KEY_SPEC_SESSION_KEYRING;
 750
 751         if (keyctl_instantiate(keyid, NULL, 0, inst_keyring)) {
 752                 logmsg(LL_ERR, "instantiate key %08x: %s\n",
 753                        keyid, strerror(errno));
 754                 return 1;
 755         }
 756
 757         logmsg(LL_TRACE, "instantiated kernel key %08x\n", keyid);
 758
 759         /*
 760          * fork a child to do the real gss negotiation
 761          */
 762         child = fork();
 763         if (child == -1) {
 764                 logmsg(LL_ERR, "key %08x: can't create child: %s\n",
 765                        keyid, strerror(errno));
 766                 return 1;
 767         } else if (child == 0) {
 768                 return lgssc_kr_negotiate(keyid, cred, &uparam);
 769         }
 770
 771         logmsg(LL_TRACE, "forked child %d\n", child);
 772         return 0;
 773 }