drivers/staging/lustre/lustre/ptlrpc/gss/gss_krb5_mech.c

   1 /*
   2  * Modifications for Lustre
   3  *
   4  * Copyright (c) 2007, 2010, Oracle and/or its affiliates. All rights reserved.
   5  *
   6  * Copyright (c) 2011, 2012, Intel Corporation.
   7  *
   8  * Author: Eric Mei <ericm@clusterfs.com>
   9  */
  10
  11 /*
  12  *  linux/net/sunrpc/gss_krb5_mech.c
  13  *  linux/net/sunrpc/gss_krb5_crypto.c
  14  *  linux/net/sunrpc/gss_krb5_seal.c
  15  *  linux/net/sunrpc/gss_krb5_seqnum.c
  16  *  linux/net/sunrpc/gss_krb5_unseal.c
  17  *
  18  *  Copyright (c) 2001 The Regents of the University of Michigan.
  19  *  All rights reserved.
  20  *
  21  *  Andy Adamson <andros@umich.edu>
  22  *  J. Bruce Fields <bfields@umich.edu>
  23  *
  24  *  Redistribution and use in source and binary forms, with or without
  25  *  modification, are permitted provided that the following conditions
  26  *  are met:
  27  *
  28  *  1. Redistributions of source code must retain the above copyright
  29  *     notice, this list of conditions and the following disclaimer.
  30  *  2. Redistributions in binary form must reproduce the above copyright
  31  *     notice, this list of conditions and the following disclaimer in the
  32  *     documentation and/or other materials provided with the distribution.
  33  *  3. Neither the name of the University nor the names of its
  34  *     contributors may be used to endorse or promote products derived
  35  *     from this software without specific prior written permission.
  36  *
  37  *  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
  38  *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  39  *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  40  *  DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  41  *  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  42  *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  43  *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
  44  *  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  45  *  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  46  *  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  47  *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  48  *
  49  */
  50
  51 #define DEBUG_SUBSYSTEM S_SEC
  52 #include <linux/init.h>
  53 #include <linux/module.h>
  54 #include <linux/slab.h>
  55 #include <linux/crypto.h>
  56 #include <linux/mutex.h>
  57
  58 #include <obd.h>
  59 #include <obd_class.h>
  60 #include <obd_support.h>
  61 #include <lustre/lustre_idl.h>
  62 #include <lustre_net.h>
  63 #include <lustre_import.h>
  64 #include <lustre_sec.h>
  65
  66 #include "gss_err.h"
  67 #include "gss_internal.h"
  68 #include "gss_api.h"
  69 #include "gss_asn1.h"
  70 #include "gss_krb5.h"
  71
  72 static spinlock_t krb5_seq_lock;
  73
  74 struct krb5_enctype {
  75         char       *ke_dispname;
  76         char       *ke_enc_name;            /* linux tfm name */
  77         char       *ke_hash_name;          /* linux tfm name */
  78         int          ke_enc_mode;           /* linux tfm mode */
  79         int          ke_hash_size;         /* checksum size */
  80         int          ke_conf_size;         /* confounder size */
  81         unsigned int    ke_hash_hmac:1;  /* is hmac? */
  82 };
  83
  84 /*
  85  * NOTE: for aes128-cts and aes256-cts, MIT implementation use CTS encryption.
  86  * but currently we simply CBC with padding, because linux doesn't support CTS
  87  * yet. this need to be fixed in the future.
  88  */
  89 static struct krb5_enctype enctypes[] = {
  90         [ENCTYPE_DES_CBC_RAW] = {              /* des-cbc-md5 */
  91                 "des-cbc-md5",
  92                 "cbc(des)",
  93                 "md5",
  94                 0,
  95                 16,
  96                 8,
  97                 0,
  98         },
  99         [ENCTYPE_DES3_CBC_RAW] = {            /* des3-hmac-sha1 */
 100                 "des3-hmac-sha1",
 101                 "cbc(des3_ede)",
 102                 "hmac(sha1)",
 103                 0,
 104                 20,
 105                 8,
 106                 1,
 107         },
 108         [ENCTYPE_AES128_CTS_HMAC_SHA1_96] = {   /* aes128-cts */
 109                 "aes128-cts-hmac-sha1-96",
 110                 "cbc(aes)",
 111                 "hmac(sha1)",
 112                 0,
 113                 12,
 114                 16,
 115                 1,
 116         },
 117         [ENCTYPE_AES256_CTS_HMAC_SHA1_96] = {   /* aes256-cts */
 118                 "aes256-cts-hmac-sha1-96",
 119                 "cbc(aes)",
 120                 "hmac(sha1)",
 121                 0,
 122                 12,
 123                 16,
 124                 1,
 125         },
 126         [ENCTYPE_ARCFOUR_HMAC] = {            /* arcfour-hmac-md5 */
 127                 "arcfour-hmac-md5",
 128                 "ecb(arc4)",
 129                 "hmac(md5)",
 130                 0,
 131                 16,
 132                 8,
 133                 1,
 134         },
 135 };
 136
 137 #define MAX_ENCTYPES    sizeof(enctypes)/sizeof(struct krb5_enctype)
 138
 139 static const char * enctype2str(__u32 enctype)
 140 {
 141         if (enctype < MAX_ENCTYPES && enctypes[enctype].ke_dispname)
 142                 return enctypes[enctype].ke_dispname;
 143
 144         return "unknown";
 145 }
 146
 147 static
 148 int keyblock_init(struct krb5_keyblock *kb, char *alg_name, int alg_mode)
 149 {
 150         kb->kb_tfm = ll_crypto_alloc_blkcipher(alg_name, alg_mode, 0);
 151         if (IS_ERR(kb->kb_tfm)) {
 152                 CERROR("failed to alloc tfm: %s, mode %d\n",
 153                        alg_name, alg_mode);
 154                 return -1;
 155         }
 156
 157         if (ll_crypto_blkcipher_setkey(kb->kb_tfm, kb->kb_key.data, kb->kb_key.len)) {
 158                 CERROR("failed to set %s key, len %d\n",
 159                        alg_name, kb->kb_key.len);
 160                 return -1;
 161         }
 162
 163         return 0;
 164 }
 165
 166 static
 167 int krb5_init_keys(struct krb5_ctx *kctx)
 168 {
 169         struct krb5_enctype *ke;
 170
 171         if (kctx->kc_enctype >= MAX_ENCTYPES ||
 172             enctypes[kctx->kc_enctype].ke_hash_size == 0) {
 173                 CERROR("unsupported enctype %x\n", kctx->kc_enctype);
 174                 return -1;
 175         }
 176
 177         ke = &enctypes[kctx->kc_enctype];
 178
 179         /* tfm arc4 is stateful, user should alloc-use-free by his own */
 180         if (kctx->kc_enctype != ENCTYPE_ARCFOUR_HMAC &&
 181             keyblock_init(&kctx->kc_keye, ke->ke_enc_name, ke->ke_enc_mode))
 182                 return -1;
 183
 184         /* tfm hmac is stateful, user should alloc-use-free by his own */
 185         if (ke->ke_hash_hmac == 0 &&
 186             keyblock_init(&kctx->kc_keyi, ke->ke_enc_name, ke->ke_enc_mode))
 187                 return -1;
 188         if (ke->ke_hash_hmac == 0 &&
 189             keyblock_init(&kctx->kc_keyc, ke->ke_enc_name, ke->ke_enc_mode))
 190                 return -1;
 191
 192         return 0;
 193 }
 194
 195 static
 196 void keyblock_free(struct krb5_keyblock *kb)
 197 {
 198         rawobj_free(&kb->kb_key);
 199         if (kb->kb_tfm)
 200                 ll_crypto_free_blkcipher(kb->kb_tfm);
 201 }
 202
 203 static
 204 int keyblock_dup(struct krb5_keyblock *new, struct krb5_keyblock *kb)
 205 {
 206         return rawobj_dup(&new->kb_key, &kb->kb_key);
 207 }
 208
 209 static
 210 int get_bytes(char **ptr, const char *end, void *res, int len)
 211 {
 212         char *p, *q;
 213         p = *ptr;
 214         q = p + len;
 215         if (q > end || q < p)
 216                 return -1;
 217         memcpy(res, p, len);
 218         *ptr = q;
 219         return 0;
 220 }
 221
 222 static
 223 int get_rawobj(char **ptr, const char *end, rawobj_t *res)
 224 {
 225         char   *p, *q;
 226         __u32   len;
 227
 228         p = *ptr;
 229         if (get_bytes(&p, end, &len, sizeof(len)))
 230                 return -1;
 231
 232         q = p + len;
 233         if (q > end || q < p)
 234                 return -1;
 235
 236         OBD_ALLOC_LARGE(res->data, len);
 237         if (!res->data)
 238                 return -1;
 239
 240         res->len = len;
 241         memcpy(res->data, p, len);
 242         *ptr = q;
 243         return 0;
 244 }
 245
 246 static
 247 int get_keyblock(char **ptr, const char *end,
 248                  struct krb5_keyblock *kb, __u32 keysize)
 249 {
 250         char *buf;
 251
 252         OBD_ALLOC_LARGE(buf, keysize);
 253         if (buf == NULL)
 254                 return -1;
 255
 256         if (get_bytes(ptr, end, buf, keysize)) {
 257                 OBD_FREE_LARGE(buf, keysize);
 258                 return -1;
 259         }
 260
 261         kb->kb_key.len = keysize;
 262         kb->kb_key.data = buf;
 263         return 0;
 264 }
 265
 266 static
 267 void delete_context_kerberos(struct krb5_ctx *kctx)
 268 {
 269         rawobj_free(&kctx->kc_mech_used);
 270
 271         keyblock_free(&kctx->kc_keye);
 272         keyblock_free(&kctx->kc_keyi);
 273         keyblock_free(&kctx->kc_keyc);
 274 }
 275
 276 static
 277 __u32 import_context_rfc1964(struct krb5_ctx *kctx, char *p, char *end)
 278 {
 279         unsigned int    tmp_uint, keysize;
 280
 281         /* seed_init flag */
 282         if (get_bytes(&p, end, &tmp_uint, sizeof(tmp_uint)))
 283                 goto out_err;
 284         kctx->kc_seed_init = (tmp_uint != 0);
 285
 286         /* seed */
 287         if (get_bytes(&p, end, kctx->kc_seed, sizeof(kctx->kc_seed)))
 288                 goto out_err;
 289
 290         /* sign/seal algorithm, not really used now */
 291         if (get_bytes(&p, end, &tmp_uint, sizeof(tmp_uint)) ||
 292             get_bytes(&p, end, &tmp_uint, sizeof(tmp_uint)))
 293                 goto out_err;
 294
 295         /* end time */
 296         if (get_bytes(&p, end, &kctx->kc_endtime, sizeof(kctx->kc_endtime)))
 297                 goto out_err;
 298
 299         /* seq send */
 300         if (get_bytes(&p, end, &tmp_uint, sizeof(tmp_uint)))
 301                 goto out_err;
 302         kctx->kc_seq_send = tmp_uint;
 303
 304         /* mech oid */
 305         if (get_rawobj(&p, end, &kctx->kc_mech_used))
 306                 goto out_err;
 307
 308         /* old style enc/seq keys in format:
 309          *   - enctype (u32)
 310          *   - keysize (u32)
 311          *   - keydata
 312          * we decompose them to fit into the new context
 313          */
 314
 315         /* enc key */
 316         if (get_bytes(&p, end, &kctx->kc_enctype, sizeof(kctx->kc_enctype)))
 317                 goto out_err;
 318
 319         if (get_bytes(&p, end, &keysize, sizeof(keysize)))
 320                 goto out_err;
 321
 322         if (get_keyblock(&p, end, &kctx->kc_keye, keysize))
 323                 goto out_err;
 324
 325         /* seq key */
 326         if (get_bytes(&p, end, &tmp_uint, sizeof(tmp_uint)) ||
 327             tmp_uint != kctx->kc_enctype)
 328                 goto out_err;
 329
 330         if (get_bytes(&p, end, &tmp_uint, sizeof(tmp_uint)) ||
 331             tmp_uint != keysize)
 332                 goto out_err;
 333
 334         if (get_keyblock(&p, end, &kctx->kc_keyc, keysize))
 335                 goto out_err;
 336
 337         /* old style fallback */
 338         if (keyblock_dup(&kctx->kc_keyi, &kctx->kc_keyc))
 339                 goto out_err;
 340
 341         if (p != end)
 342                 goto out_err;
 343
 344         CDEBUG(D_SEC, "successfully imported rfc1964 context\n");
 345         return 0;
 346 out_err:
 347         return GSS_S_FAILURE;
 348 }
 349
 350 /* Flags for version 2 context flags */
 351 #define KRB5_CTX_FLAG_INITIATOR         0x00000001
 352 #define KRB5_CTX_FLAG_CFX               0x00000002
 353 #define KRB5_CTX_FLAG_ACCEPTOR_SUBKEY   0x00000004
 354
 355 static
 356 __u32 import_context_rfc4121(struct krb5_ctx *kctx, char *p, char *end)
 357 {
 358         unsigned int    tmp_uint, keysize;
 359
 360         /* end time */
 361         if (get_bytes(&p, end, &kctx->kc_endtime, sizeof(kctx->kc_endtime)))
 362                 goto out_err;
 363
 364         /* flags */
 365         if (get_bytes(&p, end, &tmp_uint, sizeof(tmp_uint)))
 366                 goto out_err;
 367
 368         if (tmp_uint & KRB5_CTX_FLAG_INITIATOR)
 369                 kctx->kc_initiate = 1;
 370         if (tmp_uint & KRB5_CTX_FLAG_CFX)
 371                 kctx->kc_cfx = 1;
 372         if (tmp_uint & KRB5_CTX_FLAG_ACCEPTOR_SUBKEY)
 373                 kctx->kc_have_acceptor_subkey = 1;
 374
 375         /* seq send */
 376         if (get_bytes(&p, end, &kctx->kc_seq_send, sizeof(kctx->kc_seq_send)))
 377                 goto out_err;
 378
 379         /* enctype */
 380         if (get_bytes(&p, end, &kctx->kc_enctype, sizeof(kctx->kc_enctype)))
 381                 goto out_err;
 382
 383         /* size of each key */
 384         if (get_bytes(&p, end, &keysize, sizeof(keysize)))
 385                 goto out_err;
 386
 387         /* number of keys - should always be 3 */
 388         if (get_bytes(&p, end, &tmp_uint, sizeof(tmp_uint)))
 389                 goto out_err;
 390
 391         if (tmp_uint != 3) {
 392                 CERROR("Invalid number of keys: %u\n", tmp_uint);
 393                 goto out_err;
 394         }
 395
 396         /* ke */
 397         if (get_keyblock(&p, end, &kctx->kc_keye, keysize))
 398                 goto out_err;
 399         /* ki */
 400         if (get_keyblock(&p, end, &kctx->kc_keyi, keysize))
 401                 goto out_err;
 402         /* ki */
 403         if (get_keyblock(&p, end, &kctx->kc_keyc, keysize))
 404                 goto out_err;
 405
 406         CDEBUG(D_SEC, "successfully imported v2 context\n");
 407         return 0;
 408 out_err:
 409         return GSS_S_FAILURE;
 410 }
 411
 412 /*
 413  * The whole purpose here is trying to keep user level gss context parsing
 414  * from nfs-utils unchanged as possible as we can, they are not quite mature
 415  * yet, and many stuff still not clear, like heimdal etc.
 416  */
 417 static
 418 __u32 gss_import_sec_context_kerberos(rawobj_t *inbuf,
 419                                       struct gss_ctx *gctx)
 420 {
 421         struct krb5_ctx *kctx;
 422         char        *p = (char *) inbuf->data;
 423         char        *end = (char *) (inbuf->data + inbuf->len);
 424         unsigned int     tmp_uint, rc;
 425
 426         if (get_bytes(&p, end, &tmp_uint, sizeof(tmp_uint))) {
 427                 CERROR("Fail to read version\n");
 428                 return GSS_S_FAILURE;
 429         }
 430
 431         /* only support 0, 1 for the moment */
 432         if (tmp_uint > 2) {
 433                 CERROR("Invalid version %u\n", tmp_uint);
 434                 return GSS_S_FAILURE;
 435         }
 436
 437         OBD_ALLOC_PTR(kctx);
 438         if (!kctx)
 439                 return GSS_S_FAILURE;
 440
 441         if (tmp_uint == 0 || tmp_uint == 1) {
 442                 kctx->kc_initiate = tmp_uint;
 443                 rc = import_context_rfc1964(kctx, p, end);
 444         } else {
 445                 rc = import_context_rfc4121(kctx, p, end);
 446         }
 447
 448         if (rc == 0)
 449                 rc = krb5_init_keys(kctx);
 450
 451         if (rc) {
 452                 delete_context_kerberos(kctx);
 453                 OBD_FREE_PTR(kctx);
 454
 455                 return GSS_S_FAILURE;
 456         }
 457
 458         gctx->internal_ctx_id = kctx;
 459         return GSS_S_COMPLETE;
 460 }
 461
 462 static
 463 __u32 gss_copy_reverse_context_kerberos(struct gss_ctx *gctx,
 464                                         struct gss_ctx *gctx_new)
 465 {
 466         struct krb5_ctx *kctx = gctx->internal_ctx_id;
 467         struct krb5_ctx *knew;
 468
 469         OBD_ALLOC_PTR(knew);
 470         if (!knew)
 471                 return GSS_S_FAILURE;
 472
 473         knew->kc_initiate = kctx->kc_initiate ? 0 : 1;
 474         knew->kc_cfx = kctx->kc_cfx;
 475         knew->kc_seed_init = kctx->kc_seed_init;
 476         knew->kc_have_acceptor_subkey = kctx->kc_have_acceptor_subkey;
 477         knew->kc_endtime = kctx->kc_endtime;
 478
 479         memcpy(knew->kc_seed, kctx->kc_seed, sizeof(kctx->kc_seed));
 480         knew->kc_seq_send = kctx->kc_seq_recv;
 481         knew->kc_seq_recv = kctx->kc_seq_send;
 482         knew->kc_enctype = kctx->kc_enctype;
 483
 484         if (rawobj_dup(&knew->kc_mech_used, &kctx->kc_mech_used))
 485                 goto out_err;
 486
 487         if (keyblock_dup(&knew->kc_keye, &kctx->kc_keye))
 488                 goto out_err;
 489         if (keyblock_dup(&knew->kc_keyi, &kctx->kc_keyi))
 490                 goto out_err;
 491         if (keyblock_dup(&knew->kc_keyc, &kctx->kc_keyc))
 492                 goto out_err;
 493         if (krb5_init_keys(knew))
 494                 goto out_err;
 495
 496         gctx_new->internal_ctx_id = knew;
 497         CDEBUG(D_SEC, "successfully copied reverse context\n");
 498         return GSS_S_COMPLETE;
 499
 500 out_err:
 501         delete_context_kerberos(knew);
 502         OBD_FREE_PTR(knew);
 503         return GSS_S_FAILURE;
 504 }
 505
 506 static
 507 __u32 gss_inquire_context_kerberos(struct gss_ctx *gctx,
 508                                    unsigned long  *endtime)
 509 {
 510         struct krb5_ctx *kctx = gctx->internal_ctx_id;
 511
 512         *endtime = (unsigned long) ((__u32) kctx->kc_endtime);
 513         return GSS_S_COMPLETE;
 514 }
 515
 516 static
 517 void gss_delete_sec_context_kerberos(void *internal_ctx)
 518 {
 519         struct krb5_ctx *kctx = internal_ctx;
 520
 521         delete_context_kerberos(kctx);
 522         OBD_FREE_PTR(kctx);
 523 }
 524
 525 static
 526 void buf_to_sg(struct scatterlist *sg, void *ptr, int len)
 527 {
 528         sg_set_buf(sg, ptr, len);
 529 }
 530
 531 static
 532 __u32 krb5_encrypt(struct ll_crypto_cipher *tfm,
 533                    int decrypt,
 534                    void * iv,
 535                    void * in,
 536                    void * out,
 537                    int length)
 538 {
 539         struct blkcipher_desc desc;
 540         struct scatterlist    sg;
 541         __u8 local_iv[16] = {0};
 542         __u32 ret = -EINVAL;
 543
 544         LASSERT(tfm);
 545         desc.tfm  = tfm;
 546         desc.info = local_iv;
 547         desc.flags= 0;
 548
 549         if (length % ll_crypto_blkcipher_blocksize(tfm) != 0) {
 550                 CERROR("output length %d mismatch blocksize %d\n",
 551                        length, ll_crypto_blkcipher_blocksize(tfm));
 552                 goto out;
 553         }
 554
 555         if (ll_crypto_blkcipher_ivsize(tfm) > 16) {
 556                 CERROR("iv size too large %d\n", ll_crypto_blkcipher_ivsize(tfm));
 557                 goto out;
 558         }
 559
 560         if (iv)
 561                 memcpy(local_iv, iv, ll_crypto_blkcipher_ivsize(tfm));
 562
 563         memcpy(out, in, length);
 564         buf_to_sg(&sg, out, length);
 565
 566         if (decrypt)
 567                 ret = ll_crypto_blkcipher_decrypt_iv(&desc, &sg, &sg, length);
 568         else
 569                 ret = ll_crypto_blkcipher_encrypt_iv(&desc, &sg, &sg, length);
 570
 571 out:
 572         return(ret);
 573 }
 574
 575
 576 static inline
 577 int krb5_digest_hmac(struct ll_crypto_hash *tfm,
 578                      rawobj_t *key,
 579                      struct krb5_header *khdr,
 580                      int msgcnt, rawobj_t *msgs,
 581                      int iovcnt, lnet_kiov_t *iovs,
 582                      rawobj_t *cksum)
 583 {
 584         struct hash_desc   desc;
 585         struct scatterlist sg[1];
 586         int             i;
 587
 588         ll_crypto_hash_setkey(tfm, key->data, key->len);
 589         desc.tfm  = tfm;
 590         desc.flags= 0;
 591
 592         ll_crypto_hash_init(&desc);
 593
 594         for (i = 0; i < msgcnt; i++) {
 595                 if (msgs[i].len == 0)
 596                         continue;
 597                 buf_to_sg(sg, (char *) msgs[i].data, msgs[i].len);
 598                 ll_crypto_hash_update(&desc, sg, msgs[i].len);
 599         }
 600
 601         for (i = 0; i < iovcnt; i++) {
 602                 if (iovs[i].kiov_len == 0)
 603                         continue;
 604
 605                 sg_set_page(&sg[0], iovs[i].kiov_page, iovs[i].kiov_len,
 606                             iovs[i].kiov_offset);
 607                 ll_crypto_hash_update(&desc, sg, iovs[i].kiov_len);
 608         }
 609
 610         if (khdr) {
 611                 buf_to_sg(sg, (char *) khdr, sizeof(*khdr));
 612                 ll_crypto_hash_update(&desc, sg, sizeof(*khdr));
 613         }
 614
 615         return ll_crypto_hash_final(&desc, cksum->data);
 616 }
 617
 618
 619 static inline
 620 int krb5_digest_norm(struct ll_crypto_hash *tfm,
 621                      struct krb5_keyblock *kb,
 622                      struct krb5_header *khdr,
 623                      int msgcnt, rawobj_t *msgs,
 624                      int iovcnt, lnet_kiov_t *iovs,
 625                      rawobj_t *cksum)
 626 {
 627         struct hash_desc   desc;
 628         struct scatterlist sg[1];
 629         int             i;
 630
 631         LASSERT(kb->kb_tfm);
 632         desc.tfm  = tfm;
 633         desc.flags= 0;
 634
 635         ll_crypto_hash_init(&desc);
 636
 637         for (i = 0; i < msgcnt; i++) {
 638                 if (msgs[i].len == 0)
 639                         continue;
 640                 buf_to_sg(sg, (char *) msgs[i].data, msgs[i].len);
 641                 ll_crypto_hash_update(&desc, sg, msgs[i].len);
 642         }
 643
 644         for (i = 0; i < iovcnt; i++) {
 645                 if (iovs[i].kiov_len == 0)
 646                         continue;
 647
 648                 sg_set_page(&sg[0], iovs[i].kiov_page, iovs[i].kiov_len,
 649                             iovs[i].kiov_offset);
 650                 ll_crypto_hash_update(&desc, sg, iovs[i].kiov_len);
 651         }
 652
 653         if (khdr) {
 654                 buf_to_sg(sg, (char *) khdr, sizeof(*khdr));
 655                 ll_crypto_hash_update(&desc, sg, sizeof(*khdr));
 656         }
 657
 658         ll_crypto_hash_final(&desc, cksum->data);
 659
 660         return krb5_encrypt(kb->kb_tfm, 0, NULL, cksum->data,
 661                             cksum->data, cksum->len);
 662 }
 663
 664 /*
 665  * compute (keyed/keyless) checksum against the plain text which appended
 666  * with krb5 wire token header.
 667  */
 668 static
 669 __s32 krb5_make_checksum(__u32 enctype,
 670                          struct krb5_keyblock *kb,
 671                          struct krb5_header *khdr,
 672                          int msgcnt, rawobj_t *msgs,
 673                          int iovcnt, lnet_kiov_t *iovs,
 674                          rawobj_t *cksum)
 675 {
 676         struct krb5_enctype   *ke = &enctypes[enctype];
 677         struct ll_crypto_hash *tfm;
 678         __u32             code = GSS_S_FAILURE;
 679         int                 rc;
 680
 681         if (!(tfm = ll_crypto_alloc_hash(ke->ke_hash_name, 0, 0))) {
 682                 CERROR("failed to alloc TFM: %s\n", ke->ke_hash_name);
 683                 return GSS_S_FAILURE;
 684         }
 685
 686         cksum->len = ll_crypto_hash_digestsize(tfm);
 687         OBD_ALLOC_LARGE(cksum->data, cksum->len);
 688         if (!cksum->data) {
 689                 cksum->len = 0;
 690                 goto out_tfm;
 691         }
 692
 693         if (ke->ke_hash_hmac)
 694                 rc = krb5_digest_hmac(tfm, &kb->kb_key,
 695                                       khdr, msgcnt, msgs, iovcnt, iovs, cksum);
 696         else
 697                 rc = krb5_digest_norm(tfm, kb,
 698                                       khdr, msgcnt, msgs, iovcnt, iovs, cksum);
 699
 700         if (rc == 0)
 701                 code = GSS_S_COMPLETE;
 702 out_tfm:
 703         ll_crypto_free_hash(tfm);
 704         return code;
 705 }
 706
 707 static void fill_krb5_header(struct krb5_ctx *kctx,
 708                              struct krb5_header *khdr,
 709                              int privacy)
 710 {
 711         unsigned char acceptor_flag;
 712
 713         acceptor_flag = kctx->kc_initiate ? 0 : FLAG_SENDER_IS_ACCEPTOR;
 714
 715         if (privacy) {
 716                 khdr->kh_tok_id = cpu_to_be16(KG_TOK_WRAP_MSG);
 717                 khdr->kh_flags = acceptor_flag | FLAG_WRAP_CONFIDENTIAL;
 718                 khdr->kh_ec = cpu_to_be16(0);
 719                 khdr->kh_rrc = cpu_to_be16(0);
 720         } else {
 721                 khdr->kh_tok_id = cpu_to_be16(KG_TOK_MIC_MSG);
 722                 khdr->kh_flags = acceptor_flag;
 723                 khdr->kh_ec = cpu_to_be16(0xffff);
 724                 khdr->kh_rrc = cpu_to_be16(0xffff);
 725         }
 726
 727         khdr->kh_filler = 0xff;
 728         spin_lock(&krb5_seq_lock);
 729         khdr->kh_seq = cpu_to_be64(kctx->kc_seq_send++);
 730         spin_unlock(&krb5_seq_lock);
 731 }
 732
 733 static __u32 verify_krb5_header(struct krb5_ctx *kctx,
 734                                 struct krb5_header *khdr,
 735                                 int privacy)
 736 {
 737         unsigned char acceptor_flag;
 738         __u16    tok_id, ec_rrc;
 739
 740         acceptor_flag = kctx->kc_initiate ? FLAG_SENDER_IS_ACCEPTOR : 0;
 741
 742         if (privacy) {
 743                 tok_id = KG_TOK_WRAP_MSG;
 744                 ec_rrc = 0x0;
 745         } else {
 746                 tok_id = KG_TOK_MIC_MSG;
 747                 ec_rrc = 0xffff;
 748         }
 749
 750         /* sanity checks */
 751         if (be16_to_cpu(khdr->kh_tok_id) != tok_id) {
 752                 CERROR("bad token id\n");
 753                 return GSS_S_DEFECTIVE_TOKEN;
 754         }
 755         if ((khdr->kh_flags & FLAG_SENDER_IS_ACCEPTOR) != acceptor_flag) {
 756                 CERROR("bad direction flag\n");
 757                 return GSS_S_BAD_SIG;
 758         }
 759         if (privacy && (khdr->kh_flags & FLAG_WRAP_CONFIDENTIAL) == 0) {
 760                 CERROR("missing confidential flag\n");
 761                 return GSS_S_BAD_SIG;
 762         }
 763         if (khdr->kh_filler != 0xff) {
 764                 CERROR("bad filler\n");
 765                 return GSS_S_DEFECTIVE_TOKEN;
 766         }
 767         if (be16_to_cpu(khdr->kh_ec) != ec_rrc ||
 768             be16_to_cpu(khdr->kh_rrc) != ec_rrc) {
 769                 CERROR("bad EC or RRC\n");
 770                 return GSS_S_DEFECTIVE_TOKEN;
 771         }
 772         return GSS_S_COMPLETE;
 773 }
 774
 775 static
 776 __u32 gss_get_mic_kerberos(struct gss_ctx *gctx,
 777                            int msgcnt,
 778                            rawobj_t *msgs,
 779                            int iovcnt,
 780                            lnet_kiov_t *iovs,
 781                            rawobj_t *token)
 782 {
 783         struct krb5_ctx     *kctx = gctx->internal_ctx_id;
 784         struct krb5_enctype *ke = &enctypes[kctx->kc_enctype];
 785         struct krb5_header  *khdr;
 786         rawobj_t             cksum = RAWOBJ_EMPTY;
 787
 788         /* fill krb5 header */
 789         LASSERT(token->len >= sizeof(*khdr));
 790         khdr = (struct krb5_header *) token->data;
 791         fill_krb5_header(kctx, khdr, 0);
 792
 793         /* checksum */
 794         if (krb5_make_checksum(kctx->kc_enctype, &kctx->kc_keyc,
 795                                khdr, msgcnt, msgs, iovcnt, iovs, &cksum))
 796                 return GSS_S_FAILURE;
 797
 798         LASSERT(cksum.len >= ke->ke_hash_size);
 799         LASSERT(token->len >= sizeof(*khdr) + ke->ke_hash_size);
 800         memcpy(khdr + 1, cksum.data + cksum.len - ke->ke_hash_size,
 801                ke->ke_hash_size);
 802
 803         token->len = sizeof(*khdr) + ke->ke_hash_size;
 804         rawobj_free(&cksum);
 805         return GSS_S_COMPLETE;
 806 }
 807
 808 static
 809 __u32 gss_verify_mic_kerberos(struct gss_ctx *gctx,
 810                               int msgcnt,
 811                               rawobj_t *msgs,
 812                               int iovcnt,
 813                               lnet_kiov_t *iovs,
 814                               rawobj_t *token)
 815 {
 816         struct krb5_ctx     *kctx = gctx->internal_ctx_id;
 817         struct krb5_enctype *ke = &enctypes[kctx->kc_enctype];
 818         struct krb5_header  *khdr;
 819         rawobj_t             cksum = RAWOBJ_EMPTY;
 820         __u32           major;
 821
 822         if (token->len < sizeof(*khdr)) {
 823                 CERROR("short signature: %u\n", token->len);
 824                 return GSS_S_DEFECTIVE_TOKEN;
 825         }
 826
 827         khdr = (struct krb5_header *) token->data;
 828
 829         major = verify_krb5_header(kctx, khdr, 0);
 830         if (major != GSS_S_COMPLETE) {
 831                 CERROR("bad krb5 header\n");
 832                 return major;
 833         }
 834
 835         if (token->len < sizeof(*khdr) + ke->ke_hash_size) {
 836                 CERROR("short signature: %u, require %d\n",
 837                        token->len, (int) sizeof(*khdr) + ke->ke_hash_size);
 838                 return GSS_S_FAILURE;
 839         }
 840
 841         if (krb5_make_checksum(kctx->kc_enctype, &kctx->kc_keyc,
 842                                khdr, msgcnt, msgs, iovcnt, iovs, &cksum)) {
 843                 CERROR("failed to make checksum\n");
 844                 return GSS_S_FAILURE;
 845         }
 846
 847         LASSERT(cksum.len >= ke->ke_hash_size);
 848         if (memcmp(khdr + 1, cksum.data + cksum.len - ke->ke_hash_size,
 849                    ke->ke_hash_size)) {
 850                 CERROR("checksum mismatch\n");
 851                 rawobj_free(&cksum);
 852                 return GSS_S_BAD_SIG;
 853         }
 854
 855         rawobj_free(&cksum);
 856         return GSS_S_COMPLETE;
 857 }
 858
 859 static
 860 int add_padding(rawobj_t *msg, int msg_buflen, int blocksize)
 861 {
 862         int padding;
 863
 864         padding = (blocksize - (msg->len & (blocksize - 1))) &
 865                   (blocksize - 1);
 866         if (!padding)
 867                 return 0;
 868
 869         if (msg->len + padding > msg_buflen) {
 870                 CERROR("bufsize %u too small: datalen %u, padding %u\n",
 871                         msg_buflen, msg->len, padding);
 872                 return -EINVAL;
 873         }
 874
 875         memset(msg->data + msg->len, padding, padding);
 876         msg->len += padding;
 877         return 0;
 878 }
 879
 880 static
 881 int krb5_encrypt_rawobjs(struct ll_crypto_cipher *tfm,
 882                          int mode_ecb,
 883                          int inobj_cnt,
 884                          rawobj_t *inobjs,
 885                          rawobj_t *outobj,
 886                          int enc)
 887 {
 888         struct blkcipher_desc desc;
 889         struct scatterlist    src, dst;
 890         __u8              local_iv[16] = {0}, *buf;
 891         __u32            datalen = 0;
 892         int                i, rc;
 893         ENTRY;
 894
 895         buf = outobj->data;
 896         desc.tfm  = tfm;
 897         desc.info = local_iv;
 898         desc.flags = 0;
 899
 900         for (i = 0; i < inobj_cnt; i++) {
 901                 LASSERT(buf + inobjs[i].len <= outobj->data + outobj->len);
 902
 903                 buf_to_sg(&src, inobjs[i].data, inobjs[i].len);
 904                 buf_to_sg(&dst, buf, outobj->len - datalen);
 905
 906                 if (mode_ecb) {
 907                         if (enc)
 908                                 rc = ll_crypto_blkcipher_encrypt(
 909                                         &desc, &dst, &src, src.length);
 910                         else
 911                                 rc = ll_crypto_blkcipher_decrypt(
 912                                         &desc, &dst, &src, src.length);
 913                 } else {
 914                         if (enc)
 915                                 rc = ll_crypto_blkcipher_encrypt_iv(
 916                                         &desc, &dst, &src, src.length);
 917                         else
 918                                 rc = ll_crypto_blkcipher_decrypt_iv(
 919                                         &desc, &dst, &src, src.length);
 920                 }
 921
 922                 if (rc) {
 923                         CERROR("encrypt error %d\n", rc);
 924                         RETURN(rc);
 925                 }
 926
 927                 datalen += inobjs[i].len;
 928                 buf += inobjs[i].len;
 929         }
 930
 931         outobj->len = datalen;
 932         RETURN(0);
 933 }
 934
 935 /*
 936  * if adj_nob != 0, we adjust desc->bd_nob to the actual cipher text size.
 937  */
 938 static
 939 int krb5_encrypt_bulk(struct ll_crypto_cipher *tfm,
 940                       struct krb5_header *khdr,
 941                       char *confounder,
 942                       struct ptlrpc_bulk_desc *desc,
 943                       rawobj_t *cipher,
 944                       int adj_nob)
 945 {
 946         struct blkcipher_desc   ciph_desc;
 947         __u8                local_iv[16] = {0};
 948         struct scatterlist      src, dst;
 949         int                  blocksize, i, rc, nob = 0;
 950
 951         LASSERT(desc->bd_iov_count);
 952         LASSERT(desc->bd_enc_iov);
 953
 954         blocksize = ll_crypto_blkcipher_blocksize(tfm);
 955         LASSERT(blocksize > 1);
 956         LASSERT(cipher->len == blocksize + sizeof(*khdr));
 957
 958         ciph_desc.tfm  = tfm;
 959         ciph_desc.info = local_iv;
 960         ciph_desc.flags = 0;
 961
 962         /* encrypt confounder */
 963         buf_to_sg(&src, confounder, blocksize);
 964         buf_to_sg(&dst, cipher->data, blocksize);
 965
 966         rc = ll_crypto_blkcipher_encrypt_iv(&ciph_desc, &dst, &src, blocksize);
 967         if (rc) {
 968                 CERROR("error to encrypt confounder: %d\n", rc);
 969                 return rc;
 970         }
 971
 972         /* encrypt clear pages */
 973         for (i = 0; i < desc->bd_iov_count; i++) {
 974                 sg_set_page(&src, desc->bd_iov[i].kiov_page,
 975                             (desc->bd_iov[i].kiov_len + blocksize - 1) &
 976                             (~(blocksize - 1)),
 977                             desc->bd_iov[i].kiov_offset);
 978                 if (adj_nob)
 979                         nob += src.length;
 980                 sg_set_page(&dst, desc->bd_enc_iov[i].kiov_page, src.length,
 981                             src.offset);
 982
 983                 desc->bd_enc_iov[i].kiov_offset = dst.offset;
 984                 desc->bd_enc_iov[i].kiov_len = dst.length;
 985
 986                 rc = ll_crypto_blkcipher_encrypt_iv(&ciph_desc, &dst, &src,
 987                                                     src.length);
 988                 if (rc) {
 989                         CERROR("error to encrypt page: %d\n", rc);
 990                         return rc;
 991                 }
 992         }
 993
 994         /* encrypt krb5 header */
 995         buf_to_sg(&src, khdr, sizeof(*khdr));
 996         buf_to_sg(&dst, cipher->data + blocksize, sizeof(*khdr));
 997
 998         rc = ll_crypto_blkcipher_encrypt_iv(&ciph_desc,
 999                                             &dst, &src, sizeof(*khdr));
1000         if (rc) {
1001                 CERROR("error to encrypt krb5 header: %d\n", rc);
1002                 return rc;
1003         }
1004
1005         if (adj_nob)
1006                 desc->bd_nob = nob;
1007
1008         return 0;
1009 }
1010
1011 /*
1012  * desc->bd_nob_transferred is the size of cipher text received.
1013  * desc->bd_nob is the target size of plain text supposed to be.
1014  *
1015  * if adj_nob != 0, we adjust each page's kiov_len to the actual
1016  * plain text size.
1017  * - for client read: we don't know data size for each page, so
1018  *   bd_iov[]->kiov_len is set to PAGE_SIZE, but actual data received might
1019  *   be smaller, so we need to adjust it according to bd_enc_iov[]->kiov_len.
1020  *   this means we DO NOT support the situation that server send an odd size
1021  *   data in a page which is not the last one.
1022  * - for server write: we knows exactly data size for each page being expected,
1023  *   thus kiov_len is accurate already, so we should not adjust it at all.
1024  *   and bd_enc_iov[]->kiov_len should be round_up(bd_iov[]->kiov_len) which
1025  *   should have been done by prep_bulk().
1026  */
1027 static
1028 int krb5_decrypt_bulk(struct ll_crypto_cipher *tfm,
1029                       struct krb5_header *khdr,
1030                       struct ptlrpc_bulk_desc *desc,
1031                       rawobj_t *cipher,
1032                       rawobj_t *plain,
1033                       int adj_nob)
1034 {
1035         struct blkcipher_desc   ciph_desc;
1036         __u8                local_iv[16] = {0};
1037         struct scatterlist      src, dst;
1038         int                  ct_nob = 0, pt_nob = 0;
1039         int                  blocksize, i, rc;
1040
1041         LASSERT(desc->bd_iov_count);
1042         LASSERT(desc->bd_enc_iov);
1043         LASSERT(desc->bd_nob_transferred);
1044
1045         blocksize = ll_crypto_blkcipher_blocksize(tfm);
1046         LASSERT(blocksize > 1);
1047         LASSERT(cipher->len == blocksize + sizeof(*khdr));
1048
1049         ciph_desc.tfm  = tfm;
1050         ciph_desc.info = local_iv;
1051         ciph_desc.flags = 0;
1052
1053         if (desc->bd_nob_transferred % blocksize) {
1054                 CERROR("odd transferred nob: %d\n", desc->bd_nob_transferred);
1055                 return -EPROTO;
1056         }
1057
1058         /* decrypt head (confounder) */
1059         buf_to_sg(&src, cipher->data, blocksize);
1060         buf_to_sg(&dst, plain->data, blocksize);
1061
1062         rc = ll_crypto_blkcipher_decrypt_iv(&ciph_desc, &dst, &src, blocksize);
1063         if (rc) {
1064                 CERROR("error to decrypt confounder: %d\n", rc);
1065                 return rc;
1066         }
1067
1068         for (i = 0; i < desc->bd_iov_count && ct_nob < desc->bd_nob_transferred;
1069              i++) {
1070                 if (desc->bd_enc_iov[i].kiov_offset % blocksize != 0 ||
1071                     desc->bd_enc_iov[i].kiov_len % blocksize != 0) {
1072                         CERROR("page %d: odd offset %u len %u, blocksize %d\n",
1073                                i, desc->bd_enc_iov[i].kiov_offset,
1074                                desc->bd_enc_iov[i].kiov_len, blocksize);
1075                         return -EFAULT;
1076                 }
1077
1078                 if (adj_nob) {
1079                         if (ct_nob + desc->bd_enc_iov[i].kiov_len >
1080                             desc->bd_nob_transferred)
1081                                 desc->bd_enc_iov[i].kiov_len =
1082                                         desc->bd_nob_transferred - ct_nob;
1083
1084                         desc->bd_iov[i].kiov_len = desc->bd_enc_iov[i].kiov_len;
1085                         if (pt_nob + desc->bd_enc_iov[i].kiov_len >desc->bd_nob)
1086                                 desc->bd_iov[i].kiov_len = desc->bd_nob -pt_nob;
1087                 } else {
1088                         /* this should be guaranteed by LNET */
1089                         LASSERT(ct_nob + desc->bd_enc_iov[i].kiov_len <=
1090                                 desc->bd_nob_transferred);
1091                         LASSERT(desc->bd_iov[i].kiov_len <=
1092                                 desc->bd_enc_iov[i].kiov_len);
1093                 }
1094
1095                 if (desc->bd_enc_iov[i].kiov_len == 0)
1096                         continue;
1097
1098                 sg_set_page(&src, desc->bd_enc_iov[i].kiov_page,
1099                             desc->bd_enc_iov[i].kiov_len,
1100                             desc->bd_enc_iov[i].kiov_offset);
1101                 dst = src;
1102                 if (desc->bd_iov[i].kiov_len % blocksize == 0)
1103                         sg_assign_page(&dst, desc->bd_iov[i].kiov_page);
1104
1105                 rc = ll_crypto_blkcipher_decrypt_iv(&ciph_desc, &dst, &src,
1106                                                     src.length);
1107                 if (rc) {
1108                         CERROR("error to decrypt page: %d\n", rc);
1109                         return rc;
1110                 }
1111
1112                 if (desc->bd_iov[i].kiov_len % blocksize != 0) {
1113                         memcpy(page_address(desc->bd_iov[i].kiov_page) +
1114                                desc->bd_iov[i].kiov_offset,
1115                                page_address(desc->bd_enc_iov[i].kiov_page) +
1116                                desc->bd_iov[i].kiov_offset,
1117                                desc->bd_iov[i].kiov_len);
1118                 }
1119
1120                 ct_nob += desc->bd_enc_iov[i].kiov_len;
1121                 pt_nob += desc->bd_iov[i].kiov_len;
1122         }
1123
1124         if (unlikely(ct_nob != desc->bd_nob_transferred)) {
1125                 CERROR("%d cipher text transferred but only %d decrypted\n",
1126                        desc->bd_nob_transferred, ct_nob);
1127                 return -EFAULT;
1128         }
1129
1130         if (unlikely(!adj_nob && pt_nob != desc->bd_nob)) {
1131                 CERROR("%d plain text expected but only %d received\n",
1132                        desc->bd_nob, pt_nob);
1133                 return -EFAULT;
1134         }
1135
1136         /* if needed, clear up the rest unused iovs */
1137         if (adj_nob)
1138                 while (i < desc->bd_iov_count)
1139                         desc->bd_iov[i++].kiov_len = 0;
1140
1141         /* decrypt tail (krb5 header) */
1142         buf_to_sg(&src, cipher->data + blocksize, sizeof(*khdr));
1143         buf_to_sg(&dst, cipher->data + blocksize, sizeof(*khdr));
1144
1145         rc = ll_crypto_blkcipher_decrypt_iv(&ciph_desc,
1146                                             &dst, &src, sizeof(*khdr));
1147         if (rc) {
1148                 CERROR("error to decrypt tail: %d\n", rc);
1149                 return rc;
1150         }
1151
1152         if (memcmp(cipher->data + blocksize, khdr, sizeof(*khdr))) {
1153                 CERROR("krb5 header doesn't match\n");
1154                 return -EACCES;
1155         }
1156
1157         return 0;
1158 }
1159
1160 static
1161 __u32 gss_wrap_kerberos(struct gss_ctx *gctx,
1162                         rawobj_t *gsshdr,
1163                         rawobj_t *msg,
1164                         int msg_buflen,
1165                         rawobj_t *token)
1166 {
1167         struct krb5_ctx     *kctx = gctx->internal_ctx_id;
1168         struct krb5_enctype *ke = &enctypes[kctx->kc_enctype];
1169         struct krb5_header  *khdr;
1170         int               blocksize;
1171         rawobj_t             cksum = RAWOBJ_EMPTY;
1172         rawobj_t             data_desc[3], cipher;
1173         __u8             conf[GSS_MAX_CIPHER_BLOCK];
1174         int               rc = 0;
1175
1176         LASSERT(ke);
1177         LASSERT(ke->ke_conf_size <= GSS_MAX_CIPHER_BLOCK);
1178         LASSERT(kctx->kc_keye.kb_tfm == NULL ||
1179                 ke->ke_conf_size >=
1180                 ll_crypto_blkcipher_blocksize(kctx->kc_keye.kb_tfm));
1181
1182         /*
1183          * final token format:
1184          * ---------------------------------------------------
1185          * | krb5 header | cipher text | checksum (16 bytes) |
1186          * ---------------------------------------------------
1187          */
1188
1189         /* fill krb5 header */
1190         LASSERT(token->len >= sizeof(*khdr));
1191         khdr = (struct krb5_header *) token->data;
1192         fill_krb5_header(kctx, khdr, 1);
1193
1194         /* generate confounder */
1195         cfs_get_random_bytes(conf, ke->ke_conf_size);
1196
1197         /* get encryption blocksize. note kc_keye might not associated with
1198          * a tfm, currently only for arcfour-hmac */
1199         if (kctx->kc_enctype == ENCTYPE_ARCFOUR_HMAC) {
1200                 LASSERT(kctx->kc_keye.kb_tfm == NULL);
1201                 blocksize = 1;
1202         } else {
1203                 LASSERT(kctx->kc_keye.kb_tfm);
1204                 blocksize = ll_crypto_blkcipher_blocksize(kctx->kc_keye.kb_tfm);
1205         }
1206         LASSERT(blocksize <= ke->ke_conf_size);
1207
1208         /* padding the message */
1209         if (add_padding(msg, msg_buflen, blocksize))
1210                 return GSS_S_FAILURE;
1211
1212         /*
1213          * clear text layout for checksum:
1214          * ------------------------------------------------------
1215          * | confounder | gss header | clear msgs | krb5 header |
1216          * ------------------------------------------------------
1217          */
1218         data_desc[0].data = conf;
1219         data_desc[0].len = ke->ke_conf_size;
1220         data_desc[1].data = gsshdr->data;
1221         data_desc[1].len = gsshdr->len;
1222         data_desc[2].data = msg->data;
1223         data_desc[2].len = msg->len;
1224
1225         /* compute checksum */
1226         if (krb5_make_checksum(kctx->kc_enctype, &kctx->kc_keyi,
1227                                khdr, 3, data_desc, 0, NULL, &cksum))
1228                 return GSS_S_FAILURE;
1229         LASSERT(cksum.len >= ke->ke_hash_size);
1230
1231         /*
1232          * clear text layout for encryption:
1233          * -----------------------------------------
1234          * | confounder | clear msgs | krb5 header |
1235          * -----------------------------------------
1236          */
1237         data_desc[0].data = conf;
1238         data_desc[0].len = ke->ke_conf_size;
1239         data_desc[1].data = msg->data;
1240         data_desc[1].len = msg->len;
1241         data_desc[2].data = (__u8 *) khdr;
1242         data_desc[2].len = sizeof(*khdr);
1243
1244         /* cipher text will be directly inplace */
1245         cipher.data = (__u8 *) (khdr + 1);
1246         cipher.len = token->len - sizeof(*khdr);
1247         LASSERT(cipher.len >= ke->ke_conf_size + msg->len + sizeof(*khdr));
1248
1249         if (kctx->kc_enctype == ENCTYPE_ARCFOUR_HMAC) {
1250                 rawobj_t                 arc4_keye;
1251                 struct ll_crypto_cipher *arc4_tfm;
1252
1253                 if (krb5_make_checksum(ENCTYPE_ARCFOUR_HMAC, &kctx->kc_keyi,
1254                                        NULL, 1, &cksum, 0, NULL, &arc4_keye)) {
1255                         CERROR("failed to obtain arc4 enc key\n");
1256                         GOTO(arc4_out, rc = -EACCES);
1257                 }
1258
1259                 arc4_tfm = ll_crypto_alloc_blkcipher("ecb(arc4)", 0, 0);
1260                 if (IS_ERR(arc4_tfm)) {
1261                         CERROR("failed to alloc tfm arc4 in ECB mode\n");
1262                         GOTO(arc4_out_key, rc = -EACCES);
1263                 }
1264
1265                 if (ll_crypto_blkcipher_setkey(arc4_tfm, arc4_keye.data,
1266                                                arc4_keye.len)) {
1267                         CERROR("failed to set arc4 key, len %d\n",
1268                                arc4_keye.len);
1269                         GOTO(arc4_out_tfm, rc = -EACCES);
1270                 }
1271
1272                 rc = krb5_encrypt_rawobjs(arc4_tfm, 1,
1273                                           3, data_desc, &cipher, 1);
1274 arc4_out_tfm:
1275                 ll_crypto_free_blkcipher(arc4_tfm);
1276 arc4_out_key:
1277                 rawobj_free(&arc4_keye);
1278 arc4_out:
1279                 do {} while(0); /* just to avoid compile warning */
1280         } else {
1281                 rc = krb5_encrypt_rawobjs(kctx->kc_keye.kb_tfm, 0,
1282                                           3, data_desc, &cipher, 1);
1283         }
1284
1285         if (rc != 0) {
1286                 rawobj_free(&cksum);
1287                 return GSS_S_FAILURE;
1288         }
1289
1290         /* fill in checksum */
1291         LASSERT(token->len >= sizeof(*khdr) + cipher.len + ke->ke_hash_size);
1292         memcpy((char *)(khdr + 1) + cipher.len,
1293                cksum.data + cksum.len - ke->ke_hash_size,
1294                ke->ke_hash_size);
1295         rawobj_free(&cksum);
1296
1297         /* final token length */
1298         token->len = sizeof(*khdr) + cipher.len + ke->ke_hash_size;
1299         return GSS_S_COMPLETE;
1300 }
1301
1302 static
1303 __u32 gss_prep_bulk_kerberos(struct gss_ctx *gctx,
1304                              struct ptlrpc_bulk_desc *desc)
1305 {
1306         struct krb5_ctx     *kctx = gctx->internal_ctx_id;
1307         int               blocksize, i;
1308
1309         LASSERT(desc->bd_iov_count);
1310         LASSERT(desc->bd_enc_iov);
1311         LASSERT(kctx->kc_keye.kb_tfm);
1312
1313         blocksize = ll_crypto_blkcipher_blocksize(kctx->kc_keye.kb_tfm);
1314
1315         for (i = 0; i < desc->bd_iov_count; i++) {
1316                 LASSERT(desc->bd_enc_iov[i].kiov_page);
1317                 /*
1318                  * offset should always start at page boundary of either
1319                  * client or server side.
1320                  */
1321                 if (desc->bd_iov[i].kiov_offset & blocksize) {
1322                         CERROR("odd offset %d in page %d\n",
1323                                desc->bd_iov[i].kiov_offset, i);
1324                         return GSS_S_FAILURE;
1325                 }
1326
1327                 desc->bd_enc_iov[i].kiov_offset = desc->bd_iov[i].kiov_offset;
1328                 desc->bd_enc_iov[i].kiov_len = (desc->bd_iov[i].kiov_len +
1329                                                 blocksize - 1) & (~(blocksize - 1));
1330         }
1331
1332         return GSS_S_COMPLETE;
1333 }
1334
1335 static
1336 __u32 gss_wrap_bulk_kerberos(struct gss_ctx *gctx,
1337                              struct ptlrpc_bulk_desc *desc,
1338                              rawobj_t *token, int adj_nob)
1339 {
1340         struct krb5_ctx     *kctx = gctx->internal_ctx_id;
1341         struct krb5_enctype *ke = &enctypes[kctx->kc_enctype];
1342         struct krb5_header  *khdr;
1343         int               blocksize;
1344         rawobj_t             cksum = RAWOBJ_EMPTY;
1345         rawobj_t             data_desc[1], cipher;
1346         __u8             conf[GSS_MAX_CIPHER_BLOCK];
1347         int               rc = 0;
1348
1349         LASSERT(ke);
1350         LASSERT(ke->ke_conf_size <= GSS_MAX_CIPHER_BLOCK);
1351
1352         /*
1353          * final token format:
1354          * --------------------------------------------------
1355          * | krb5 header | head/tail cipher text | checksum |
1356          * --------------------------------------------------
1357          */
1358
1359         /* fill krb5 header */
1360         LASSERT(token->len >= sizeof(*khdr));
1361         khdr = (struct krb5_header *) token->data;
1362         fill_krb5_header(kctx, khdr, 1);
1363
1364         /* generate confounder */
1365         cfs_get_random_bytes(conf, ke->ke_conf_size);
1366
1367         /* get encryption blocksize. note kc_keye might not associated with
1368          * a tfm, currently only for arcfour-hmac */
1369         if (kctx->kc_enctype == ENCTYPE_ARCFOUR_HMAC) {
1370                 LASSERT(kctx->kc_keye.kb_tfm == NULL);
1371                 blocksize = 1;
1372         } else {
1373                 LASSERT(kctx->kc_keye.kb_tfm);
1374                 blocksize = ll_crypto_blkcipher_blocksize(kctx->kc_keye.kb_tfm);
1375         }
1376
1377         /*
1378          * we assume the size of krb5_header (16 bytes) must be n * blocksize.
1379          * the bulk token size would be exactly (sizeof(krb5_header) +
1380          * blocksize + sizeof(krb5_header) + hashsize)
1381          */
1382         LASSERT(blocksize <= ke->ke_conf_size);
1383         LASSERT(sizeof(*khdr) >= blocksize && sizeof(*khdr) % blocksize == 0);
1384         LASSERT(token->len >= sizeof(*khdr) + blocksize + sizeof(*khdr) + 16);
1385
1386         /*
1387          * clear text layout for checksum:
1388          * ------------------------------------------
1389          * | confounder | clear pages | krb5 header |
1390          * ------------------------------------------
1391          */
1392         data_desc[0].data = conf;
1393         data_desc[0].len = ke->ke_conf_size;
1394
1395         /* compute checksum */
1396         if (krb5_make_checksum(kctx->kc_enctype, &kctx->kc_keyi,
1397                                khdr, 1, data_desc,
1398                                desc->bd_iov_count, desc->bd_iov,
1399                                &cksum))
1400                 return GSS_S_FAILURE;
1401         LASSERT(cksum.len >= ke->ke_hash_size);
1402
1403         /*
1404          * clear text layout for encryption:
1405          * ------------------------------------------
1406          * | confounder | clear pages | krb5 header |
1407          * ------------------------------------------
1408          *      |             |      |
1409          *      ----------  (cipher pages)   |
1410          * result token:   |               |
1411          * -------------------------------------------
1412          * | krb5 header | cipher text | cipher text |
1413          * -------------------------------------------
1414          */
1415         data_desc[0].data = conf;
1416         data_desc[0].len = ke->ke_conf_size;
1417
1418         cipher.data = (__u8 *) (khdr + 1);
1419         cipher.len = blocksize + sizeof(*khdr);
1420
1421         if (kctx->kc_enctype == ENCTYPE_ARCFOUR_HMAC) {
1422                 LBUG();
1423                 rc = 0;
1424         } else {
1425                 rc = krb5_encrypt_bulk(kctx->kc_keye.kb_tfm, khdr,
1426                                        conf, desc, &cipher, adj_nob);
1427         }
1428
1429         if (rc != 0) {
1430                 rawobj_free(&cksum);
1431                 return GSS_S_FAILURE;
1432         }
1433
1434         /* fill in checksum */
1435         LASSERT(token->len >= sizeof(*khdr) + cipher.len + ke->ke_hash_size);
1436         memcpy((char *)(khdr + 1) + cipher.len,
1437                cksum.data + cksum.len - ke->ke_hash_size,
1438                ke->ke_hash_size);
1439         rawobj_free(&cksum);
1440
1441         /* final token length */
1442         token->len = sizeof(*khdr) + cipher.len + ke->ke_hash_size;
1443         return GSS_S_COMPLETE;
1444 }
1445
1446 static
1447 __u32 gss_unwrap_kerberos(struct gss_ctx  *gctx,
1448                           rawobj_t      *gsshdr,
1449                           rawobj_t      *token,
1450                           rawobj_t      *msg)
1451 {
1452         struct krb5_ctx     *kctx = gctx->internal_ctx_id;
1453         struct krb5_enctype *ke = &enctypes[kctx->kc_enctype];
1454         struct krb5_header  *khdr;
1455         unsigned char       *tmpbuf;
1456         int               blocksize, bodysize;
1457         rawobj_t             cksum = RAWOBJ_EMPTY;
1458         rawobj_t             cipher_in, plain_out;
1459         rawobj_t             hash_objs[3];
1460         int               rc = 0;
1461         __u32           major;
1462
1463         LASSERT(ke);
1464
1465         if (token->len < sizeof(*khdr)) {
1466                 CERROR("short signature: %u\n", token->len);
1467                 return GSS_S_DEFECTIVE_TOKEN;
1468         }
1469
1470         khdr = (struct krb5_header *) token->data;
1471
1472         major = verify_krb5_header(kctx, khdr, 1);
1473         if (major != GSS_S_COMPLETE) {
1474                 CERROR("bad krb5 header\n");
1475                 return major;
1476         }
1477
1478         /* block size */
1479         if (kctx->kc_enctype == ENCTYPE_ARCFOUR_HMAC) {
1480                 LASSERT(kctx->kc_keye.kb_tfm == NULL);
1481                 blocksize = 1;
1482         } else {
1483                 LASSERT(kctx->kc_keye.kb_tfm);
1484                 blocksize = ll_crypto_blkcipher_blocksize(kctx->kc_keye.kb_tfm);
1485         }
1486
1487         /* expected token layout:
1488          * ----------------------------------------
1489          * | krb5 header | cipher text | checksum |
1490          * ----------------------------------------
1491          */
1492         bodysize = token->len - sizeof(*khdr) - ke->ke_hash_size;
1493
1494         if (bodysize % blocksize) {
1495                 CERROR("odd bodysize %d\n", bodysize);
1496                 return GSS_S_DEFECTIVE_TOKEN;
1497         }
1498
1499         if (bodysize <= ke->ke_conf_size + sizeof(*khdr)) {
1500                 CERROR("incomplete token: bodysize %d\n", bodysize);
1501                 return GSS_S_DEFECTIVE_TOKEN;
1502         }
1503
1504         if (msg->len < bodysize - ke->ke_conf_size - sizeof(*khdr)) {
1505                 CERROR("buffer too small: %u, require %d\n",
1506                        msg->len, bodysize - ke->ke_conf_size);
1507                 return GSS_S_FAILURE;
1508         }
1509
1510         /* decrypting */
1511         OBD_ALLOC_LARGE(tmpbuf, bodysize);
1512         if (!tmpbuf)
1513                 return GSS_S_FAILURE;
1514
1515         major = GSS_S_FAILURE;
1516
1517         cipher_in.data = (__u8 *) (khdr + 1);
1518         cipher_in.len = bodysize;
1519         plain_out.data = tmpbuf;
1520         plain_out.len = bodysize;
1521
1522         if (kctx->kc_enctype == ENCTYPE_ARCFOUR_HMAC) {
1523                 rawobj_t                 arc4_keye;
1524                 struct ll_crypto_cipher *arc4_tfm;
1525
1526                 cksum.data = token->data + token->len - ke->ke_hash_size;
1527                 cksum.len = ke->ke_hash_size;
1528
1529                 if (krb5_make_checksum(ENCTYPE_ARCFOUR_HMAC, &kctx->kc_keyi,
1530                                        NULL, 1, &cksum, 0, NULL, &arc4_keye)) {
1531                         CERROR("failed to obtain arc4 enc key\n");
1532                         GOTO(arc4_out, rc = -EACCES);
1533                 }
1534
1535                 arc4_tfm = ll_crypto_alloc_blkcipher("ecb(arc4)", 0, 0);
1536                 if (IS_ERR(arc4_tfm)) {
1537                         CERROR("failed to alloc tfm arc4 in ECB mode\n");
1538                         GOTO(arc4_out_key, rc = -EACCES);
1539                 }
1540
1541                 if (ll_crypto_blkcipher_setkey(arc4_tfm,
1542                                          arc4_keye.data, arc4_keye.len)) {
1543                         CERROR("failed to set arc4 key, len %d\n",
1544                                arc4_keye.len);
1545                         GOTO(arc4_out_tfm, rc = -EACCES);
1546                 }
1547
1548                 rc = krb5_encrypt_rawobjs(arc4_tfm, 1,
1549                                           1, &cipher_in, &plain_out, 0);
1550 arc4_out_tfm:
1551                 ll_crypto_free_blkcipher(arc4_tfm);
1552 arc4_out_key:
1553                 rawobj_free(&arc4_keye);
1554 arc4_out:
1555                 cksum = RAWOBJ_EMPTY;
1556         } else {
1557                 rc = krb5_encrypt_rawobjs(kctx->kc_keye.kb_tfm, 0,
1558                                           1, &cipher_in, &plain_out, 0);
1559         }
1560
1561         if (rc != 0) {
1562                 CERROR("error decrypt\n");
1563                 goto out_free;
1564         }
1565         LASSERT(plain_out.len == bodysize);
1566
1567         /* expected clear text layout:
1568          * -----------------------------------------
1569          * | confounder | clear msgs | krb5 header |
1570          * -----------------------------------------
1571          */
1572
1573         /* verify krb5 header in token is not modified */
1574         if (memcmp(khdr, plain_out.data + plain_out.len - sizeof(*khdr),
1575                    sizeof(*khdr))) {
1576                 CERROR("decrypted krb5 header mismatch\n");
1577                 goto out_free;
1578         }
1579
1580         /* verify checksum, compose clear text as layout:
1581          * ------------------------------------------------------
1582          * | confounder | gss header | clear msgs | krb5 header |
1583          * ------------------------------------------------------
1584          */
1585         hash_objs[0].len = ke->ke_conf_size;
1586         hash_objs[0].data = plain_out.data;
1587         hash_objs[1].len = gsshdr->len;
1588         hash_objs[1].data = gsshdr->data;
1589         hash_objs[2].len = plain_out.len - ke->ke_conf_size - sizeof(*khdr);
1590         hash_objs[2].data = plain_out.data + ke->ke_conf_size;
1591         if (krb5_make_checksum(kctx->kc_enctype, &kctx->kc_keyi,
1592                                khdr, 3, hash_objs, 0, NULL, &cksum))
1593                 goto out_free;
1594
1595         LASSERT(cksum.len >= ke->ke_hash_size);
1596         if (memcmp((char *)(khdr + 1) + bodysize,
1597                    cksum.data + cksum.len - ke->ke_hash_size,
1598                    ke->ke_hash_size)) {
1599                 CERROR("checksum mismatch\n");
1600                 goto out_free;
1601         }
1602
1603         msg->len =  bodysize - ke->ke_conf_size - sizeof(*khdr);
1604         memcpy(msg->data, tmpbuf + ke->ke_conf_size, msg->len);
1605
1606         major = GSS_S_COMPLETE;
1607 out_free:
1608         OBD_FREE_LARGE(tmpbuf, bodysize);
1609         rawobj_free(&cksum);
1610         return major;
1611 }
1612
1613 static
1614 __u32 gss_unwrap_bulk_kerberos(struct gss_ctx *gctx,
1615                                struct ptlrpc_bulk_desc *desc,
1616                                rawobj_t *token, int adj_nob)
1617 {
1618         struct krb5_ctx     *kctx = gctx->internal_ctx_id;
1619         struct krb5_enctype *ke = &enctypes[kctx->kc_enctype];
1620         struct krb5_header  *khdr;
1621         int               blocksize;
1622         rawobj_t             cksum = RAWOBJ_EMPTY;
1623         rawobj_t             cipher, plain;
1624         rawobj_t             data_desc[1];
1625         int               rc;
1626         __u32           major;
1627
1628         LASSERT(ke);
1629
1630         if (token->len < sizeof(*khdr)) {
1631                 CERROR("short signature: %u\n", token->len);
1632                 return GSS_S_DEFECTIVE_TOKEN;
1633         }
1634
1635         khdr = (struct krb5_header *) token->data;
1636
1637         major = verify_krb5_header(kctx, khdr, 1);
1638         if (major != GSS_S_COMPLETE) {
1639                 CERROR("bad krb5 header\n");
1640                 return major;
1641         }
1642
1643         /* block size */
1644         if (kctx->kc_enctype == ENCTYPE_ARCFOUR_HMAC) {
1645                 LASSERT(kctx->kc_keye.kb_tfm == NULL);
1646                 blocksize = 1;
1647                 LBUG();
1648         } else {
1649                 LASSERT(kctx->kc_keye.kb_tfm);
1650                 blocksize = ll_crypto_blkcipher_blocksize(kctx->kc_keye.kb_tfm);
1651         }
1652         LASSERT(sizeof(*khdr) >= blocksize && sizeof(*khdr) % blocksize == 0);
1653
1654         /*
1655          * token format is expected as:
1656          * -----------------------------------------------
1657          * | krb5 header | head/tail cipher text | cksum |
1658          * -----------------------------------------------
1659          */
1660         if (token->len < sizeof(*khdr) + blocksize + sizeof(*khdr) +
1661                          ke->ke_hash_size) {
1662                 CERROR("short token size: %u\n", token->len);
1663                 return GSS_S_DEFECTIVE_TOKEN;
1664         }
1665
1666         cipher.data = (__u8 *) (khdr + 1);
1667         cipher.len = blocksize + sizeof(*khdr);
1668         plain.data = cipher.data;
1669         plain.len = cipher.len;
1670
1671         rc = krb5_decrypt_bulk(kctx->kc_keye.kb_tfm, khdr,
1672                                desc, &cipher, &plain, adj_nob);
1673         if (rc)
1674                 return GSS_S_DEFECTIVE_TOKEN;
1675
1676         /*
1677          * verify checksum, compose clear text as layout:
1678          * ------------------------------------------
1679          * | confounder | clear pages | krb5 header |
1680          * ------------------------------------------
1681          */
1682         data_desc[0].data = plain.data;
1683         data_desc[0].len = blocksize;
1684
1685         if (krb5_make_checksum(kctx->kc_enctype, &kctx->kc_keyi,
1686                                khdr, 1, data_desc,
1687                                desc->bd_iov_count, desc->bd_iov,
1688                                &cksum))
1689                 return GSS_S_FAILURE;
1690         LASSERT(cksum.len >= ke->ke_hash_size);
1691
1692         if (memcmp(plain.data + blocksize + sizeof(*khdr),
1693                    cksum.data + cksum.len - ke->ke_hash_size,
1694                    ke->ke_hash_size)) {
1695                 CERROR("checksum mismatch\n");
1696                 rawobj_free(&cksum);
1697                 return GSS_S_BAD_SIG;
1698         }
1699
1700         rawobj_free(&cksum);
1701         return GSS_S_COMPLETE;
1702 }
1703
1704 int gss_display_kerberos(struct gss_ctx *ctx,
1705                          char             *buf,
1706                          int                bufsize)
1707 {
1708         struct krb5_ctx    *kctx = ctx->internal_ctx_id;
1709         int              written;
1710
1711         written = snprintf(buf, bufsize, "krb5 (%s)",
1712                            enctype2str(kctx->kc_enctype));
1713         return written;
1714 }
1715
1716 static struct gss_api_ops gss_kerberos_ops = {
1717         .gss_import_sec_context     = gss_import_sec_context_kerberos,
1718         .gss_copy_reverse_context   = gss_copy_reverse_context_kerberos,
1719         .gss_inquire_context    = gss_inquire_context_kerberos,
1720         .gss_get_mic            = gss_get_mic_kerberos,
1721         .gss_verify_mic      = gss_verify_mic_kerberos,
1722         .gss_wrap                  = gss_wrap_kerberos,
1723         .gss_unwrap              = gss_unwrap_kerberos,
1724         .gss_prep_bulk        = gss_prep_bulk_kerberos,
1725         .gss_wrap_bulk        = gss_wrap_bulk_kerberos,
1726         .gss_unwrap_bulk            = gss_unwrap_bulk_kerberos,
1727         .gss_delete_sec_context     = gss_delete_sec_context_kerberos,
1728         .gss_display            = gss_display_kerberos,
1729 };
1730
1731 static struct subflavor_desc gss_kerberos_sfs[] = {
1732         {
1733                 .sf_subflavor   = SPTLRPC_SUBFLVR_KRB5N,
1734                 .sf_qop  = 0,
1735                 .sf_service     = SPTLRPC_SVC_NULL,
1736                 .sf_name        = "krb5n"
1737         },
1738         {
1739                 .sf_subflavor   = SPTLRPC_SUBFLVR_KRB5A,
1740                 .sf_qop  = 0,
1741                 .sf_service     = SPTLRPC_SVC_AUTH,
1742                 .sf_name        = "krb5a"
1743         },
1744         {
1745                 .sf_subflavor   = SPTLRPC_SUBFLVR_KRB5I,
1746                 .sf_qop  = 0,
1747                 .sf_service     = SPTLRPC_SVC_INTG,
1748                 .sf_name        = "krb5i"
1749         },
1750         {
1751                 .sf_subflavor   = SPTLRPC_SUBFLVR_KRB5P,
1752                 .sf_qop  = 0,
1753                 .sf_service     = SPTLRPC_SVC_PRIV,
1754                 .sf_name        = "krb5p"
1755         },
1756 };
1757
1758 /*
1759  * currently we leave module owner NULL
1760  */
1761 static struct gss_api_mech gss_kerberos_mech = {
1762         .gm_owner       = NULL, /*THIS_MODULE, */
1763         .gm_name        = "krb5",
1764         .gm_oid  = (rawobj_t)
1765                                 {9, "\052\206\110\206\367\022\001\002\002"},
1766         .gm_ops  = &gss_kerberos_ops,
1767         .gm_sf_num      = 4,
1768         .gm_sfs  = gss_kerberos_sfs,
1769 };
1770
1771 int __init init_kerberos_module(void)
1772 {
1773         int status;
1774
1775         spin_lock_init(&krb5_seq_lock);
1776
1777         status = lgss_mech_register(&gss_kerberos_mech);
1778         if (status)
1779                 CERROR("Failed to register kerberos gss mechanism!\n");
1780         return status;
1781 }
1782
1783 void __exit cleanup_kerberos_module(void)
1784 {
1785         lgss_mech_unregister(&gss_kerberos_mech);
1786 }