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   1 /*
   2  *  linux/net/sunrpc/gss_krb5_mech.c
   3  *
   4  *  Copyright (c) 2001-2008 The Regents of the University of Michigan.
   5  *  All rights reserved.
   6  *
   7  *  Andy Adamson <andros@umich.edu>
   8  *  J. Bruce Fields <bfields@umich.edu>
   9  *
  10  *  Redistribution and use in source and binary forms, with or without
  11  *  modification, are permitted provided that the following conditions
  12  *  are met:
  13  *
  14  *  1. Redistributions of source code must retain the above copyright
  15  *     notice, this list of conditions and the following disclaimer.
  16  *  2. Redistributions in binary form must reproduce the above copyright
  17  *     notice, this list of conditions and the following disclaimer in the
  18  *     documentation and/or other materials provided with the distribution.
  19  *  3. Neither the name of the University nor the names of its
  20  *     contributors may be used to endorse or promote products derived
  21  *     from this software without specific prior written permission.
  22  *
  23  *  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
  24  *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  25  *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  26  *  DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  27  *  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  28  *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  29  *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
  30  *  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
  31  *  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
  32  *  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
  33  *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  34  *
  35  */
  36
  37 #include <linux/err.h>
  38 #include <linux/module.h>
  39 #include <linux/init.h>
  40 #include <linux/types.h>
  41 #include <linux/slab.h>
  42 #include <linux/sunrpc/auth.h>
  43 #include <linux/sunrpc/gss_krb5.h>
  44 #include <linux/sunrpc/xdr.h>
  45 #include <linux/crypto.h>
  46
  47 #ifdef RPC_DEBUG
  48 # define RPCDBG_FACILITY        RPCDBG_AUTH
  49 #endif
  50
  51 static struct gss_api_mech gss_kerberos_mech;   /* forward declaration */
  52
  53 static const struct gss_krb5_enctype supported_gss_krb5_enctypes[] = {
  54         /*
  55          * DES (All DES enctypes are mapped to the same gss functionality)
  56          */
  57         {
  58           .etype = ENCTYPE_DES_CBC_RAW,
  59           .ctype = CKSUMTYPE_RSA_MD5,
  60           .name = "des-cbc-crc",
  61           .encrypt_name = "cbc(des)",
  62           .cksum_name = "md5",
  63           .encrypt = krb5_encrypt,
  64           .decrypt = krb5_decrypt,
  65           .mk_key = NULL,
  66           .signalg = SGN_ALG_DES_MAC_MD5,
  67           .sealalg = SEAL_ALG_DES,
  68           .keybytes = 7,
  69           .keylength = 8,
  70           .blocksize = 8,
  71           .cksumlength = 8,
  72           .keyed_cksum = 0,
  73         },
  74         /*
  75          * 3DES
  76          */
  77         {
  78           .etype = ENCTYPE_DES3_CBC_RAW,
  79           .ctype = CKSUMTYPE_HMAC_SHA1_DES3,
  80           .name = "des3-hmac-sha1",
  81           .encrypt_name = "cbc(des3_ede)",
  82           .cksum_name = "hmac(sha1)",
  83           .encrypt = krb5_encrypt,
  84           .decrypt = krb5_decrypt,
  85           .mk_key = gss_krb5_des3_make_key,
  86           .signalg = SGN_ALG_HMAC_SHA1_DES3_KD,
  87           .sealalg = SEAL_ALG_DES3KD,
  88           .keybytes = 21,
  89           .keylength = 24,
  90           .blocksize = 8,
  91           .cksumlength = 20,
  92           .keyed_cksum = 1,
  93         },
  94         /*
  95          * AES128
  96          */
  97         {
  98           .etype = ENCTYPE_AES128_CTS_HMAC_SHA1_96,
  99           .ctype = CKSUMTYPE_HMAC_SHA1_96_AES128,
 100           .name = "aes128-cts",
 101           .encrypt_name = "cts(cbc(aes))",
 102           .cksum_name = "hmac(sha1)",
 103           .encrypt = krb5_encrypt,
 104           .decrypt = krb5_decrypt,
 105           .mk_key = gss_krb5_aes_make_key,
 106           .encrypt_v2 = gss_krb5_aes_encrypt,
 107           .decrypt_v2 = gss_krb5_aes_decrypt,
 108           .signalg = -1,
 109           .sealalg = -1,
 110           .keybytes = 16,
 111           .keylength = 16,
 112           .blocksize = 16,
 113           .cksumlength = 12,
 114           .keyed_cksum = 1,
 115         },
 116         /*
 117          * AES256
 118          */
 119         {
 120           .etype = ENCTYPE_AES256_CTS_HMAC_SHA1_96,
 121           .ctype = CKSUMTYPE_HMAC_SHA1_96_AES256,
 122           .name = "aes256-cts",
 123           .encrypt_name = "cts(cbc(aes))",
 124           .cksum_name = "hmac(sha1)",
 125           .encrypt = krb5_encrypt,
 126           .decrypt = krb5_decrypt,
 127           .mk_key = gss_krb5_aes_make_key,
 128           .encrypt_v2 = gss_krb5_aes_encrypt,
 129           .decrypt_v2 = gss_krb5_aes_decrypt,
 130           .signalg = -1,
 131           .sealalg = -1,
 132           .keybytes = 32,
 133           .keylength = 32,
 134           .blocksize = 16,
 135           .cksumlength = 12,
 136           .keyed_cksum = 1,
 137         },
 138 };
 139
 140 static const int num_supported_enctypes =
 141         ARRAY_SIZE(supported_gss_krb5_enctypes);
 142
 143 static int
 144 supported_gss_krb5_enctype(int etype)
 145 {
 146         int i;
 147         for (i = 0; i < num_supported_enctypes; i++)
 148                 if (supported_gss_krb5_enctypes[i].etype == etype)
 149                         return 1;
 150         return 0;
 151 }
 152
 153 static const struct gss_krb5_enctype *
 154 get_gss_krb5_enctype(int etype)
 155 {
 156         int i;
 157         for (i = 0; i < num_supported_enctypes; i++)
 158                 if (supported_gss_krb5_enctypes[i].etype == etype)
 159                         return &supported_gss_krb5_enctypes[i];
 160         return NULL;
 161 }
 162
 163 static const void *
 164 simple_get_bytes(const void *p, const void *end, void *res, int len)
 165 {
 166         const void *q = (const void *)((const char *)p + len);
 167         if (unlikely(q > end || q < p))
 168                 return ERR_PTR(-EFAULT);
 169         memcpy(res, p, len);
 170         return q;
 171 }
 172
 173 static const void *
 174 simple_get_netobj(const void *p, const void *end, struct xdr_netobj *res)
 175 {
 176         const void *q;
 177         unsigned int len;
 178
 179         p = simple_get_bytes(p, end, &len, sizeof(len));
 180         if (IS_ERR(p))
 181                 return p;
 182         q = (const void *)((const char *)p + len);
 183         if (unlikely(q > end || q < p))
 184                 return ERR_PTR(-EFAULT);
 185         res->data = kmemdup(p, len, GFP_NOFS);
 186         if (unlikely(res->data == NULL))
 187                 return ERR_PTR(-ENOMEM);
 188         res->len = len;
 189         return q;
 190 }
 191
 192 static inline const void *
 193 get_key(const void *p, const void *end,
 194         struct krb5_ctx *ctx, struct crypto_blkcipher **res)
 195 {
 196         struct xdr_netobj       key;
 197         int                     alg;
 198
 199         p = simple_get_bytes(p, end, &alg, sizeof(alg));
 200         if (IS_ERR(p))
 201                 goto out_err;
 202
 203         switch (alg) {
 204         case ENCTYPE_DES_CBC_CRC:
 205         case ENCTYPE_DES_CBC_MD4:
 206         case ENCTYPE_DES_CBC_MD5:
 207                 /* Map all these key types to ENCTYPE_DES_CBC_RAW */
 208                 alg = ENCTYPE_DES_CBC_RAW;
 209                 break;
 210         }
 211
 212         if (!supported_gss_krb5_enctype(alg)) {
 213                 printk(KERN_WARNING "gss_kerberos_mech: unsupported "
 214                         "encryption key algorithm %d\n", alg);
 215                 goto out_err;
 216         }
 217         p = simple_get_netobj(p, end, &key);
 218         if (IS_ERR(p))
 219                 goto out_err;
 220
 221         *res = crypto_alloc_blkcipher(ctx->gk5e->encrypt_name, 0,
 222                                                         CRYPTO_ALG_ASYNC);
 223         if (IS_ERR(*res)) {
 224                 printk(KERN_WARNING "gss_kerberos_mech: unable to initialize "
 225                         "crypto algorithm %s\n", ctx->gk5e->encrypt_name);
 226                 *res = NULL;
 227                 goto out_err_free_key;
 228         }
 229         if (crypto_blkcipher_setkey(*res, key.data, key.len)) {
 230                 printk(KERN_WARNING "gss_kerberos_mech: error setting key for "
 231                         "crypto algorithm %s\n", ctx->gk5e->encrypt_name);
 232                 goto out_err_free_tfm;
 233         }
 234
 235         kfree(key.data);
 236         return p;
 237
 238 out_err_free_tfm:
 239         crypto_free_blkcipher(*res);
 240 out_err_free_key:
 241         kfree(key.data);
 242         p = ERR_PTR(-EINVAL);
 243 out_err:
 244         return p;
 245 }
 246
 247 static int
 248 gss_import_v1_context(const void *p, const void *end, struct krb5_ctx *ctx)
 249 {
 250         int tmp;
 251
 252         p = simple_get_bytes(p, end, &ctx->initiate, sizeof(ctx->initiate));
 253         if (IS_ERR(p))
 254                 goto out_err;
 255
 256         /* Old format supports only DES!  Any other enctype uses new format */
 257         ctx->enctype = ENCTYPE_DES_CBC_RAW;
 258
 259         ctx->gk5e = get_gss_krb5_enctype(ctx->enctype);
 260         if (ctx->gk5e == NULL)
 261                 goto out_err;
 262
 263         /* The downcall format was designed before we completely understood
 264          * the uses of the context fields; so it includes some stuff we
 265          * just give some minimal sanity-checking, and some we ignore
 266          * completely (like the next twenty bytes): */
 267         if (unlikely(p + 20 > end || p + 20 < p))
 268                 goto out_err;
 269         p += 20;
 270         p = simple_get_bytes(p, end, &tmp, sizeof(tmp));
 271         if (IS_ERR(p))
 272                 goto out_err;
 273         if (tmp != SGN_ALG_DES_MAC_MD5) {
 274                 p = ERR_PTR(-ENOSYS);
 275                 goto out_err;
 276         }
 277         p = simple_get_bytes(p, end, &tmp, sizeof(tmp));
 278         if (IS_ERR(p))
 279                 goto out_err;
 280         if (tmp != SEAL_ALG_DES) {
 281                 p = ERR_PTR(-ENOSYS);
 282                 goto out_err;
 283         }
 284         p = simple_get_bytes(p, end, &ctx->endtime, sizeof(ctx->endtime));
 285         if (IS_ERR(p))
 286                 goto out_err;
 287         p = simple_get_bytes(p, end, &ctx->seq_send, sizeof(ctx->seq_send));
 288         if (IS_ERR(p))
 289                 goto out_err;
 290         p = simple_get_netobj(p, end, &ctx->mech_used);
 291         if (IS_ERR(p))
 292                 goto out_err;
 293         p = get_key(p, end, ctx, &ctx->enc);
 294         if (IS_ERR(p))
 295                 goto out_err_free_mech;
 296         p = get_key(p, end, ctx, &ctx->seq);
 297         if (IS_ERR(p))
 298                 goto out_err_free_key1;
 299         if (p != end) {
 300                 p = ERR_PTR(-EFAULT);
 301                 goto out_err_free_key2;
 302         }
 303
 304         return 0;
 305
 306 out_err_free_key2:
 307         crypto_free_blkcipher(ctx->seq);
 308 out_err_free_key1:
 309         crypto_free_blkcipher(ctx->enc);
 310 out_err_free_mech:
 311         kfree(ctx->mech_used.data);
 312 out_err:
 313         return PTR_ERR(p);
 314 }
 315
 316 struct crypto_blkcipher *
 317 context_v2_alloc_cipher(struct krb5_ctx *ctx, const char *cname, u8 *key)
 318 {
 319         struct crypto_blkcipher *cp;
 320
 321         cp = crypto_alloc_blkcipher(cname, 0, CRYPTO_ALG_ASYNC);
 322         if (IS_ERR(cp)) {
 323                 dprintk("gss_kerberos_mech: unable to initialize "
 324                         "crypto algorithm %s\n", cname);
 325                 return NULL;
 326         }
 327         if (crypto_blkcipher_setkey(cp, key, ctx->gk5e->keylength)) {
 328                 dprintk("gss_kerberos_mech: error setting key for "
 329                         "crypto algorithm %s\n", cname);
 330                 crypto_free_blkcipher(cp);
 331                 return NULL;
 332         }
 333         return cp;
 334 }
 335
 336 static inline void
 337 set_cdata(u8 cdata[GSS_KRB5_K5CLENGTH], u32 usage, u8 seed)
 338 {
 339         cdata[0] = (usage>>24)&0xff;
 340         cdata[1] = (usage>>16)&0xff;
 341         cdata[2] = (usage>>8)&0xff;
 342         cdata[3] = usage&0xff;
 343         cdata[4] = seed;
 344 }
 345
 346 static int
 347 context_derive_keys_des3(struct krb5_ctx *ctx, u8 *rawkey, u32 keylen)
 348 {
 349         struct xdr_netobj c, keyin, keyout;
 350         u8 cdata[GSS_KRB5_K5CLENGTH];
 351         u32 err;
 352
 353         c.len = GSS_KRB5_K5CLENGTH;
 354         c.data = cdata;
 355
 356         keyin.data = rawkey;
 357         keyin.len = keylen;
 358         keyout.len = keylen;
 359
 360         /* seq uses the raw key */
 361         ctx->seq = context_v2_alloc_cipher(ctx, ctx->gk5e->encrypt_name,
 362                                            rawkey);
 363         if (ctx->seq == NULL)
 364                 goto out_err;
 365
 366         ctx->enc = context_v2_alloc_cipher(ctx, ctx->gk5e->encrypt_name,
 367                                            rawkey);
 368         if (ctx->enc == NULL)
 369                 goto out_free_seq;
 370
 371         /* derive cksum */
 372         set_cdata(cdata, KG_USAGE_SIGN, KEY_USAGE_SEED_CHECKSUM);
 373         keyout.data = ctx->cksum;
 374         err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c);
 375         if (err) {
 376                 dprintk("%s: Error %d deriving cksum key\n",
 377                         __func__, err);
 378                 goto out_free_enc;
 379         }
 380
 381         return 0;
 382
 383 out_free_enc:
 384         crypto_free_blkcipher(ctx->enc);
 385 out_free_seq:
 386         crypto_free_blkcipher(ctx->seq);
 387 out_err:
 388         return -EINVAL;
 389 }
 390
 391 static int
 392 context_derive_keys_new(struct krb5_ctx *ctx, u8 *rawkey, u32 keylen)
 393 {
 394         struct xdr_netobj c, keyin, keyout;
 395         u8 cdata[GSS_KRB5_K5CLENGTH];
 396         u32 err;
 397
 398         c.len = GSS_KRB5_K5CLENGTH;
 399         c.data = cdata;
 400
 401         keyin.data = rawkey;
 402         keyin.len = keylen;
 403         keyout.len = keylen;
 404
 405         /* initiator seal encryption */
 406         set_cdata(cdata, KG_USAGE_INITIATOR_SEAL, KEY_USAGE_SEED_ENCRYPTION);
 407         keyout.data = ctx->initiator_seal;
 408         err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c);
 409         if (err) {
 410                 dprintk("%s: Error %d deriving initiator_seal key\n",
 411                         __func__, err);
 412                 goto out_err;
 413         }
 414         ctx->initiator_enc = context_v2_alloc_cipher(ctx,
 415                                                      ctx->gk5e->encrypt_name,
 416                                                      ctx->initiator_seal);
 417         if (ctx->initiator_enc == NULL)
 418                 goto out_err;
 419
 420         /* acceptor seal encryption */
 421         set_cdata(cdata, KG_USAGE_ACCEPTOR_SEAL, KEY_USAGE_SEED_ENCRYPTION);
 422         keyout.data = ctx->acceptor_seal;
 423         err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c);
 424         if (err) {
 425                 dprintk("%s: Error %d deriving acceptor_seal key\n",
 426                         __func__, err);
 427                 goto out_free_initiator_enc;
 428         }
 429         ctx->acceptor_enc = context_v2_alloc_cipher(ctx,
 430                                                     ctx->gk5e->encrypt_name,
 431                                                     ctx->acceptor_seal);
 432         if (ctx->acceptor_enc == NULL)
 433                 goto out_free_initiator_enc;
 434
 435         /* initiator sign checksum */
 436         set_cdata(cdata, KG_USAGE_INITIATOR_SIGN, KEY_USAGE_SEED_CHECKSUM);
 437         keyout.data = ctx->initiator_sign;
 438         err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c);
 439         if (err) {
 440                 dprintk("%s: Error %d deriving initiator_sign key\n",
 441                         __func__, err);
 442                 goto out_free_acceptor_enc;
 443         }
 444
 445         /* acceptor sign checksum */
 446         set_cdata(cdata, KG_USAGE_ACCEPTOR_SIGN, KEY_USAGE_SEED_CHECKSUM);
 447         keyout.data = ctx->acceptor_sign;
 448         err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c);
 449         if (err) {
 450                 dprintk("%s: Error %d deriving acceptor_sign key\n",
 451                         __func__, err);
 452                 goto out_free_acceptor_enc;
 453         }
 454
 455         /* initiator seal integrity */
 456         set_cdata(cdata, KG_USAGE_INITIATOR_SEAL, KEY_USAGE_SEED_INTEGRITY);
 457         keyout.data = ctx->initiator_integ;
 458         err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c);
 459         if (err) {
 460                 dprintk("%s: Error %d deriving initiator_integ key\n",
 461                         __func__, err);
 462                 goto out_free_acceptor_enc;
 463         }
 464
 465         /* acceptor seal integrity */
 466         set_cdata(cdata, KG_USAGE_ACCEPTOR_SEAL, KEY_USAGE_SEED_INTEGRITY);
 467         keyout.data = ctx->acceptor_integ;
 468         err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c);
 469         if (err) {
 470                 dprintk("%s: Error %d deriving acceptor_integ key\n",
 471                         __func__, err);
 472                 goto out_free_acceptor_enc;
 473         }
 474
 475         switch (ctx->enctype) {
 476         case ENCTYPE_AES128_CTS_HMAC_SHA1_96:
 477         case ENCTYPE_AES256_CTS_HMAC_SHA1_96:
 478                 ctx->initiator_enc_aux =
 479                         context_v2_alloc_cipher(ctx, "cbc(aes)",
 480                                                 ctx->initiator_seal);
 481                 if (ctx->initiator_enc_aux == NULL)
 482                         goto out_free_acceptor_enc;
 483                 ctx->acceptor_enc_aux =
 484                         context_v2_alloc_cipher(ctx, "cbc(aes)",
 485                                                 ctx->acceptor_seal);
 486                 if (ctx->acceptor_enc_aux == NULL) {
 487                         crypto_free_blkcipher(ctx->initiator_enc_aux);
 488                         goto out_free_acceptor_enc;
 489                 }
 490         }
 491
 492         return 0;
 493
 494 out_free_acceptor_enc:
 495         crypto_free_blkcipher(ctx->acceptor_enc);
 496 out_free_initiator_enc:
 497         crypto_free_blkcipher(ctx->initiator_enc);
 498 out_err:
 499         return -EINVAL;
 500 }
 501
 502 static int
 503 gss_import_v2_context(const void *p, const void *end, struct krb5_ctx *ctx)
 504 {
 505         u8 rawkey[GSS_KRB5_MAX_KEYLEN];
 506         int keylen;
 507
 508         p = simple_get_bytes(p, end, &ctx->flags, sizeof(ctx->flags));
 509         if (IS_ERR(p))
 510                 goto out_err;
 511         ctx->initiate = ctx->flags & KRB5_CTX_FLAG_INITIATOR;
 512
 513         p = simple_get_bytes(p, end, &ctx->endtime, sizeof(ctx->endtime));
 514         if (IS_ERR(p))
 515                 goto out_err;
 516         p = simple_get_bytes(p, end, &ctx->seq_send64, sizeof(ctx->seq_send64));
 517         if (IS_ERR(p))
 518                 goto out_err;
 519         /* set seq_send for use by "older" enctypes */
 520         ctx->seq_send = ctx->seq_send64;
 521         if (ctx->seq_send64 != ctx->seq_send) {
 522                 dprintk("%s: seq_send64 %lx, seq_send %x overflow?\n", __func__,
 523                         (long unsigned)ctx->seq_send64, ctx->seq_send);
 524                 goto out_err;
 525         }
 526         p = simple_get_bytes(p, end, &ctx->enctype, sizeof(ctx->enctype));
 527         if (IS_ERR(p))
 528                 goto out_err;
 529         /* Map ENCTYPE_DES3_CBC_SHA1 to ENCTYPE_DES3_CBC_RAW */
 530         if (ctx->enctype == ENCTYPE_DES3_CBC_SHA1)
 531                 ctx->enctype = ENCTYPE_DES3_CBC_RAW;
 532         ctx->gk5e = get_gss_krb5_enctype(ctx->enctype);
 533         if (ctx->gk5e == NULL) {
 534                 dprintk("gss_kerberos_mech: unsupported krb5 enctype %u\n",
 535                         ctx->enctype);
 536                 p = ERR_PTR(-EINVAL);
 537                 goto out_err;
 538         }
 539         keylen = ctx->gk5e->keylength;
 540
 541         p = simple_get_bytes(p, end, rawkey, keylen);
 542         if (IS_ERR(p))
 543                 goto out_err;
 544
 545         if (p != end) {
 546                 p = ERR_PTR(-EINVAL);
 547                 goto out_err;
 548         }
 549
 550         ctx->mech_used.data = kmemdup(gss_kerberos_mech.gm_oid.data,
 551                                       gss_kerberos_mech.gm_oid.len, GFP_KERNEL);
 552         if (unlikely(ctx->mech_used.data == NULL)) {
 553                 p = ERR_PTR(-ENOMEM);
 554                 goto out_err;
 555         }
 556         ctx->mech_used.len = gss_kerberos_mech.gm_oid.len;
 557
 558         switch (ctx->enctype) {
 559         case ENCTYPE_DES3_CBC_RAW:
 560                 return context_derive_keys_des3(ctx, rawkey, keylen);
 561         case ENCTYPE_AES128_CTS_HMAC_SHA1_96:
 562         case ENCTYPE_AES256_CTS_HMAC_SHA1_96:
 563                 return context_derive_keys_new(ctx, rawkey, keylen);
 564         default:
 565                 return -EINVAL;
 566         }
 567
 568 out_err:
 569         return PTR_ERR(p);
 570 }
 571
 572 static int
 573 gss_import_sec_context_kerberos(const void *p, size_t len,
 574                                 struct gss_ctx *ctx_id)
 575 {
 576         const void *end = (const void *)((const char *)p + len);
 577         struct  krb5_ctx *ctx;
 578         int ret;
 579
 580         ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
 581         if (ctx == NULL)
 582                 return -ENOMEM;
 583
 584         if (len == 85)
 585                 ret = gss_import_v1_context(p, end, ctx);
 586         else
 587                 ret = gss_import_v2_context(p, end, ctx);
 588
 589         if (ret == 0)
 590                 ctx_id->internal_ctx_id = ctx;
 591         else
 592                 kfree(ctx);
 593
 594         dprintk("RPC:       %s: returning %d\n", __func__, ret);
 595         return ret;
 596 }
 597
 598 static void
 599 gss_delete_sec_context_kerberos(void *internal_ctx) {
 600         struct krb5_ctx *kctx = internal_ctx;
 601
 602         crypto_free_blkcipher(kctx->seq);
 603         crypto_free_blkcipher(kctx->enc);
 604         crypto_free_blkcipher(kctx->acceptor_enc);
 605         crypto_free_blkcipher(kctx->initiator_enc);
 606         crypto_free_blkcipher(kctx->acceptor_enc_aux);
 607         crypto_free_blkcipher(kctx->initiator_enc_aux);
 608         kfree(kctx->mech_used.data);
 609         kfree(kctx);
 610 }
 611
 612 static const struct gss_api_ops gss_kerberos_ops = {
 613         .gss_import_sec_context = gss_import_sec_context_kerberos,
 614         .gss_get_mic            = gss_get_mic_kerberos,
 615         .gss_verify_mic         = gss_verify_mic_kerberos,
 616         .gss_wrap               = gss_wrap_kerberos,
 617         .gss_unwrap             = gss_unwrap_kerberos,
 618         .gss_delete_sec_context = gss_delete_sec_context_kerberos,
 619 };
 620
 621 static struct pf_desc gss_kerberos_pfs[] = {
 622         [0] = {
 623                 .pseudoflavor = RPC_AUTH_GSS_KRB5,
 624                 .service = RPC_GSS_SVC_NONE,
 625                 .name = "krb5",
 626         },
 627         [1] = {
 628                 .pseudoflavor = RPC_AUTH_GSS_KRB5I,
 629                 .service = RPC_GSS_SVC_INTEGRITY,
 630                 .name = "krb5i",
 631         },
 632         [2] = {
 633                 .pseudoflavor = RPC_AUTH_GSS_KRB5P,
 634                 .service = RPC_GSS_SVC_PRIVACY,
 635                 .name = "krb5p",
 636         },
 637 };
 638
 639 static struct gss_api_mech gss_kerberos_mech = {
 640         .gm_name        = "krb5",
 641         .gm_owner       = THIS_MODULE,
 642         .gm_oid         = {9, (void *)"\x2a\x86\x48\x86\xf7\x12\x01\x02\x02"},
 643         .gm_ops         = &gss_kerberos_ops,
 644         .gm_pf_num      = ARRAY_SIZE(gss_kerberos_pfs),
 645         .gm_pfs         = gss_kerberos_pfs,
 646         .gm_upcall_enctypes = "enctypes=18,17,16,3,1,2 ",
 647 };
 648
 649 static int __init init_kerberos_module(void)
 650 {
 651         int status;
 652
 653         status = gss_mech_register(&gss_kerberos_mech);
 654         if (status)
 655                 printk("Failed to register kerberos gss mechanism!\n");
 656         return status;
 657 }
 658
 659 static void __exit cleanup_kerberos_module(void)
 660 {
 661         gss_mech_unregister(&gss_kerberos_mech);
 662 }
 663
 664 MODULE_LICENSE("GPL");
 665 module_init(init_kerberos_module);
 666 module_exit(cleanup_kerberos_module);