diff options
Diffstat (limited to 'net/sunrpc/auth_gss/gss_krb5_mech.c')
-rw-r--r-- | net/sunrpc/auth_gss/gss_krb5_mech.c | 584 |
1 files changed, 544 insertions, 40 deletions
diff --git a/net/sunrpc/auth_gss/gss_krb5_mech.c b/net/sunrpc/auth_gss/gss_krb5_mech.c index 2deb0ed72ff4..032644610524 100644 --- a/net/sunrpc/auth_gss/gss_krb5_mech.c +++ b/net/sunrpc/auth_gss/gss_krb5_mech.c @@ -1,7 +1,7 @@ /* * linux/net/sunrpc/gss_krb5_mech.c * - * Copyright (c) 2001 The Regents of the University of Michigan. + * Copyright (c) 2001-2008 The Regents of the University of Michigan. * All rights reserved. * * Andy Adamson <andros@umich.edu> @@ -48,6 +48,143 @@ # define RPCDBG_FACILITY RPCDBG_AUTH #endif +static struct gss_api_mech gss_kerberos_mech; /* forward declaration */ + +static const struct gss_krb5_enctype supported_gss_krb5_enctypes[] = { + /* + * DES (All DES enctypes are mapped to the same gss functionality) + */ + { + .etype = ENCTYPE_DES_CBC_RAW, + .ctype = CKSUMTYPE_RSA_MD5, + .name = "des-cbc-crc", + .encrypt_name = "cbc(des)", + .cksum_name = "md5", + .encrypt = krb5_encrypt, + .decrypt = krb5_decrypt, + .mk_key = NULL, + .signalg = SGN_ALG_DES_MAC_MD5, + .sealalg = SEAL_ALG_DES, + .keybytes = 7, + .keylength = 8, + .blocksize = 8, + .conflen = 8, + .cksumlength = 8, + .keyed_cksum = 0, + }, + /* + * RC4-HMAC + */ + { + .etype = ENCTYPE_ARCFOUR_HMAC, + .ctype = CKSUMTYPE_HMAC_MD5_ARCFOUR, + .name = "rc4-hmac", + .encrypt_name = "ecb(arc4)", + .cksum_name = "hmac(md5)", + .encrypt = krb5_encrypt, + .decrypt = krb5_decrypt, + .mk_key = NULL, + .signalg = SGN_ALG_HMAC_MD5, + .sealalg = SEAL_ALG_MICROSOFT_RC4, + .keybytes = 16, + .keylength = 16, + .blocksize = 1, + .conflen = 8, + .cksumlength = 8, + .keyed_cksum = 1, + }, + /* + * 3DES + */ + { + .etype = ENCTYPE_DES3_CBC_RAW, + .ctype = CKSUMTYPE_HMAC_SHA1_DES3, + .name = "des3-hmac-sha1", + .encrypt_name = "cbc(des3_ede)", + .cksum_name = "hmac(sha1)", + .encrypt = krb5_encrypt, + .decrypt = krb5_decrypt, + .mk_key = gss_krb5_des3_make_key, + .signalg = SGN_ALG_HMAC_SHA1_DES3_KD, + .sealalg = SEAL_ALG_DES3KD, + .keybytes = 21, + .keylength = 24, + .blocksize = 8, + .conflen = 8, + .cksumlength = 20, + .keyed_cksum = 1, + }, + /* + * AES128 + */ + { + .etype = ENCTYPE_AES128_CTS_HMAC_SHA1_96, + .ctype = CKSUMTYPE_HMAC_SHA1_96_AES128, + .name = "aes128-cts", + .encrypt_name = "cts(cbc(aes))", + .cksum_name = "hmac(sha1)", + .encrypt = krb5_encrypt, + .decrypt = krb5_decrypt, + .mk_key = gss_krb5_aes_make_key, + .encrypt_v2 = gss_krb5_aes_encrypt, + .decrypt_v2 = gss_krb5_aes_decrypt, + .signalg = -1, + .sealalg = -1, + .keybytes = 16, + .keylength = 16, + .blocksize = 16, + .conflen = 16, + .cksumlength = 12, + .keyed_cksum = 1, + }, + /* + * AES256 + */ + { + .etype = ENCTYPE_AES256_CTS_HMAC_SHA1_96, + .ctype = CKSUMTYPE_HMAC_SHA1_96_AES256, + .name = "aes256-cts", + .encrypt_name = "cts(cbc(aes))", + .cksum_name = "hmac(sha1)", + .encrypt = krb5_encrypt, + .decrypt = krb5_decrypt, + .mk_key = gss_krb5_aes_make_key, + .encrypt_v2 = gss_krb5_aes_encrypt, + .decrypt_v2 = gss_krb5_aes_decrypt, + .signalg = -1, + .sealalg = -1, + .keybytes = 32, + .keylength = 32, + .blocksize = 16, + .conflen = 16, + .cksumlength = 12, + .keyed_cksum = 1, + }, +}; + +static const int num_supported_enctypes = + ARRAY_SIZE(supported_gss_krb5_enctypes); + +static int +supported_gss_krb5_enctype(int etype) +{ + int i; + for (i = 0; i < num_supported_enctypes; i++) + if (supported_gss_krb5_enctypes[i].etype == etype) + return 1; + return 0; +} + +static const struct gss_krb5_enctype * +get_gss_krb5_enctype(int etype) +{ + int i; + for (i = 0; i < num_supported_enctypes; i++) + if (supported_gss_krb5_enctypes[i].etype == etype) + return &supported_gss_krb5_enctypes[i]; + return NULL; +} + static const void * simple_get_bytes(const void *p, const void *end, void *res, int len) { @@ -78,35 +215,45 @@ simple_get_netobj(const void *p, const void *end, struct xdr_netobj *res) } static inline const void * -get_key(const void *p, const void *end, struct crypto_blkcipher **res) +get_key(const void *p, const void *end, + struct krb5_ctx *ctx, struct crypto_blkcipher **res) { struct xdr_netobj key; int alg; - char *alg_name; p = simple_get_bytes(p, end, &alg, sizeof(alg)); if (IS_ERR(p)) goto out_err; + + switch (alg) { + case ENCTYPE_DES_CBC_CRC: + case ENCTYPE_DES_CBC_MD4: + case ENCTYPE_DES_CBC_MD5: + /* Map all these key types to ENCTYPE_DES_CBC_RAW */ + alg = ENCTYPE_DES_CBC_RAW; + break; + } + + if (!supported_gss_krb5_enctype(alg)) { + printk(KERN_WARNING "gss_kerberos_mech: unsupported " + "encryption key algorithm %d\n", alg); + goto out_err; + } p = simple_get_netobj(p, end, &key); if (IS_ERR(p)) goto out_err; - switch (alg) { - case ENCTYPE_DES_CBC_RAW: - alg_name = "cbc(des)"; - break; - default: - printk("gss_kerberos_mech: unsupported algorithm %d\n", alg); - goto out_err_free_key; - } - *res = crypto_alloc_blkcipher(alg_name, 0, CRYPTO_ALG_ASYNC); + *res = crypto_alloc_blkcipher(ctx->gk5e->encrypt_name, 0, + CRYPTO_ALG_ASYNC); if (IS_ERR(*res)) { - printk("gss_kerberos_mech: unable to initialize crypto algorithm %s\n", alg_name); + printk(KERN_WARNING "gss_kerberos_mech: unable to initialize " + "crypto algorithm %s\n", ctx->gk5e->encrypt_name); *res = NULL; goto out_err_free_key; } if (crypto_blkcipher_setkey(*res, key.data, key.len)) { - printk("gss_kerberos_mech: error setting key for crypto algorithm %s\n", alg_name); + printk(KERN_WARNING "gss_kerberos_mech: error setting key for " + "crypto algorithm %s\n", ctx->gk5e->encrypt_name); goto out_err_free_tfm; } @@ -123,56 +270,55 @@ out_err: } static int -gss_import_sec_context_kerberos(const void *p, - size_t len, - struct gss_ctx *ctx_id) +gss_import_v1_context(const void *p, const void *end, struct krb5_ctx *ctx) { - const void *end = (const void *)((const char *)p + len); - struct krb5_ctx *ctx; int tmp; - if (!(ctx = kzalloc(sizeof(*ctx), GFP_NOFS))) { - p = ERR_PTR(-ENOMEM); - goto out_err; - } - p = simple_get_bytes(p, end, &ctx->initiate, sizeof(ctx->initiate)); if (IS_ERR(p)) - goto out_err_free_ctx; + goto out_err; + + /* Old format supports only DES! Any other enctype uses new format */ + ctx->enctype = ENCTYPE_DES_CBC_RAW; + + ctx->gk5e = get_gss_krb5_enctype(ctx->enctype); + if (ctx->gk5e == NULL) + goto out_err; + /* The downcall format was designed before we completely understood * the uses of the context fields; so it includes some stuff we * just give some minimal sanity-checking, and some we ignore * completely (like the next twenty bytes): */ if (unlikely(p + 20 > end || p + 20 < p)) - goto out_err_free_ctx; + goto out_err; p += 20; p = simple_get_bytes(p, end, &tmp, sizeof(tmp)); if (IS_ERR(p)) - goto out_err_free_ctx; + goto out_err; if (tmp != SGN_ALG_DES_MAC_MD5) { p = ERR_PTR(-ENOSYS); - goto out_err_free_ctx; + goto out_err; } p = simple_get_bytes(p, end, &tmp, sizeof(tmp)); if (IS_ERR(p)) - goto out_err_free_ctx; + goto out_err; if (tmp != SEAL_ALG_DES) { p = ERR_PTR(-ENOSYS); - goto out_err_free_ctx; + goto out_err; } p = simple_get_bytes(p, end, &ctx->endtime, sizeof(ctx->endtime)); if (IS_ERR(p)) - goto out_err_free_ctx; + goto out_err; p = simple_get_bytes(p, end, &ctx->seq_send, sizeof(ctx->seq_send)); if (IS_ERR(p)) - goto out_err_free_ctx; + goto out_err; p = simple_get_netobj(p, end, &ctx->mech_used); if (IS_ERR(p)) - goto out_err_free_ctx; - p = get_key(p, end, &ctx->enc); + goto out_err; + p = get_key(p, end, ctx, &ctx->enc); if (IS_ERR(p)) goto out_err_free_mech; - p = get_key(p, end, &ctx->seq); + p = get_key(p, end, ctx, &ctx->seq); if (IS_ERR(p)) goto out_err_free_key1; if (p != end) { @@ -180,9 +326,6 @@ gss_import_sec_context_kerberos(const void *p, goto out_err_free_key2; } - ctx_id->internal_ctx_id = ctx; - - dprintk("RPC: Successfully imported new context.\n"); return 0; out_err_free_key2: @@ -191,18 +334,378 @@ out_err_free_key1: crypto_free_blkcipher(ctx->enc); out_err_free_mech: kfree(ctx->mech_used.data); -out_err_free_ctx: - kfree(ctx); out_err: return PTR_ERR(p); } +struct crypto_blkcipher * +context_v2_alloc_cipher(struct krb5_ctx *ctx, const char *cname, u8 *key) +{ + struct crypto_blkcipher *cp; + + cp = crypto_alloc_blkcipher(cname, 0, CRYPTO_ALG_ASYNC); + if (IS_ERR(cp)) { + dprintk("gss_kerberos_mech: unable to initialize " + "crypto algorithm %s\n", cname); + return NULL; + } + if (crypto_blkcipher_setkey(cp, key, ctx->gk5e->keylength)) { + dprintk("gss_kerberos_mech: error setting key for " + "crypto algorithm %s\n", cname); + crypto_free_blkcipher(cp); + return NULL; + } + return cp; +} + +static inline void +set_cdata(u8 cdata[GSS_KRB5_K5CLENGTH], u32 usage, u8 seed) +{ + cdata[0] = (usage>>24)&0xff; + cdata[1] = (usage>>16)&0xff; + cdata[2] = (usage>>8)&0xff; + cdata[3] = usage&0xff; + cdata[4] = seed; +} + +static int +context_derive_keys_des3(struct krb5_ctx *ctx, gfp_t gfp_mask) +{ + struct xdr_netobj c, keyin, keyout; + u8 cdata[GSS_KRB5_K5CLENGTH]; + u32 err; + + c.len = GSS_KRB5_K5CLENGTH; + c.data = cdata; + + keyin.data = ctx->Ksess; + keyin.len = ctx->gk5e->keylength; + keyout.len = ctx->gk5e->keylength; + + /* seq uses the raw key */ + ctx->seq = context_v2_alloc_cipher(ctx, ctx->gk5e->encrypt_name, + ctx->Ksess); + if (ctx->seq == NULL) + goto out_err; + + ctx->enc = context_v2_alloc_cipher(ctx, ctx->gk5e->encrypt_name, + ctx->Ksess); + if (ctx->enc == NULL) + goto out_free_seq; + + /* derive cksum */ + set_cdata(cdata, KG_USAGE_SIGN, KEY_USAGE_SEED_CHECKSUM); + keyout.data = ctx->cksum; + err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask); + if (err) { + dprintk("%s: Error %d deriving cksum key\n", + __func__, err); + goto out_free_enc; + } + + return 0; + +out_free_enc: + crypto_free_blkcipher(ctx->enc); +out_free_seq: + crypto_free_blkcipher(ctx->seq); +out_err: + return -EINVAL; +} + +/* + * Note that RC4 depends on deriving keys using the sequence + * number or the checksum of a token. Therefore, the final keys + * cannot be calculated until the token is being constructed! + */ +static int +context_derive_keys_rc4(struct krb5_ctx *ctx) +{ + struct crypto_hash *hmac; + char sigkeyconstant[] = "signaturekey"; + int slen = strlen(sigkeyconstant) + 1; /* include null terminator */ + struct hash_desc desc; + struct scatterlist sg[1]; + int err; + + dprintk("RPC: %s: entered\n", __func__); + /* + * derive cksum (aka Ksign) key + */ + hmac = crypto_alloc_hash(ctx->gk5e->cksum_name, 0, CRYPTO_ALG_ASYNC); + if (IS_ERR(hmac)) { + dprintk("%s: error %ld allocating hash '%s'\n", + __func__, PTR_ERR(hmac), ctx->gk5e->cksum_name); + err = PTR_ERR(hmac); + goto out_err; + } + + err = crypto_hash_setkey(hmac, ctx->Ksess, ctx->gk5e->keylength); + if (err) + goto out_err_free_hmac; + + sg_init_table(sg, 1); + sg_set_buf(sg, sigkeyconstant, slen); + + desc.tfm = hmac; + desc.flags = 0; + + err = crypto_hash_init(&desc); + if (err) + goto out_err_free_hmac; + + err = crypto_hash_digest(&desc, sg, slen, ctx->cksum); + if (err) + goto out_err_free_hmac; + /* + * allocate hash, and blkciphers for data and seqnum encryption + */ + ctx->enc = crypto_alloc_blkcipher(ctx->gk5e->encrypt_name, 0, + CRYPTO_ALG_ASYNC); + if (IS_ERR(ctx->enc)) { + err = PTR_ERR(ctx->enc); + goto out_err_free_hmac; + } + + ctx->seq = crypto_alloc_blkcipher(ctx->gk5e->encrypt_name, 0, + CRYPTO_ALG_ASYNC); + if (IS_ERR(ctx->seq)) { + crypto_free_blkcipher(ctx->enc); + err = PTR_ERR(ctx->seq); + goto out_err_free_hmac; + } + + dprintk("RPC: %s: returning success\n", __func__); + + err = 0; + +out_err_free_hmac: + crypto_free_hash(hmac); +out_err: + dprintk("RPC: %s: returning %d\n", __func__, err); + return err; +} + +static int +context_derive_keys_new(struct krb5_ctx *ctx, gfp_t gfp_mask) +{ + struct xdr_netobj c, keyin, keyout; + u8 cdata[GSS_KRB5_K5CLENGTH]; + u32 err; + + c.len = GSS_KRB5_K5CLENGTH; + c.data = cdata; + + keyin.data = ctx->Ksess; + keyin.len = ctx->gk5e->keylength; + keyout.len = ctx->gk5e->keylength; + + /* initiator seal encryption */ + set_cdata(cdata, KG_USAGE_INITIATOR_SEAL, KEY_USAGE_SEED_ENCRYPTION); + keyout.data = ctx->initiator_seal; + err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask); + if (err) { + dprintk("%s: Error %d deriving initiator_seal key\n", + __func__, err); + goto out_err; + } + ctx->initiator_enc = context_v2_alloc_cipher(ctx, + ctx->gk5e->encrypt_name, + ctx->initiator_seal); + if (ctx->initiator_enc == NULL) + goto out_err; + + /* acceptor seal encryption */ + set_cdata(cdata, KG_USAGE_ACCEPTOR_SEAL, KEY_USAGE_SEED_ENCRYPTION); + keyout.data = ctx->acceptor_seal; + err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask); + if (err) { + dprintk("%s: Error %d deriving acceptor_seal key\n", + __func__, err); + goto out_free_initiator_enc; + } + ctx->acceptor_enc = context_v2_alloc_cipher(ctx, + ctx->gk5e->encrypt_name, + ctx->acceptor_seal); + if (ctx->acceptor_enc == NULL) + goto out_free_initiator_enc; + + /* initiator sign checksum */ + set_cdata(cdata, KG_USAGE_INITIATOR_SIGN, KEY_USAGE_SEED_CHECKSUM); + keyout.data = ctx->initiator_sign; + err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask); + if (err) { + dprintk("%s: Error %d deriving initiator_sign key\n", + __func__, err); + goto out_free_acceptor_enc; + } + + /* acceptor sign checksum */ + set_cdata(cdata, KG_USAGE_ACCEPTOR_SIGN, KEY_USAGE_SEED_CHECKSUM); + keyout.data = ctx->acceptor_sign; + err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask); + if (err) { + dprintk("%s: Error %d deriving acceptor_sign key\n", + __func__, err); + goto out_free_acceptor_enc; + } + + /* initiator seal integrity */ + set_cdata(cdata, KG_USAGE_INITIATOR_SEAL, KEY_USAGE_SEED_INTEGRITY); + keyout.data = ctx->initiator_integ; + err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask); + if (err) { + dprintk("%s: Error %d deriving initiator_integ key\n", + __func__, err); + goto out_free_acceptor_enc; + } + + /* acceptor seal integrity */ + set_cdata(cdata, KG_USAGE_ACCEPTOR_SEAL, KEY_USAGE_SEED_INTEGRITY); + keyout.data = ctx->acceptor_integ; + err = krb5_derive_key(ctx->gk5e, &keyin, &keyout, &c, gfp_mask); + if (err) { + dprintk("%s: Error %d deriving acceptor_integ key\n", + __func__, err); + goto out_free_acceptor_enc; + } + + switch (ctx->enctype) { + case ENCTYPE_AES128_CTS_HMAC_SHA1_96: + case ENCTYPE_AES256_CTS_HMAC_SHA1_96: + ctx->initiator_enc_aux = + context_v2_alloc_cipher(ctx, "cbc(aes)", + ctx->initiator_seal); + if (ctx->initiator_enc_aux == NULL) + goto out_free_acceptor_enc; + ctx->acceptor_enc_aux = + context_v2_alloc_cipher(ctx, "cbc(aes)", + ctx->acceptor_seal); + if (ctx->acceptor_enc_aux == NULL) { + crypto_free_blkcipher(ctx->initiator_enc_aux); + goto out_free_acceptor_enc; + } + } + + return 0; + +out_free_acceptor_enc: + crypto_free_blkcipher(ctx->acceptor_enc); +out_free_initiator_enc: + crypto_free_blkcipher(ctx->initiator_enc); +out_err: + return -EINVAL; +} + +static int +gss_import_v2_context(const void *p, const void *end, struct krb5_ctx *ctx, + gfp_t gfp_mask) +{ + int keylen; + + p = simple_get_bytes(p, end, &ctx->flags, sizeof(ctx->flags)); + if (IS_ERR(p)) + goto out_err; + ctx->initiate = ctx->flags & KRB5_CTX_FLAG_INITIATOR; + + p = simple_get_bytes(p, end, &ctx->endtime, sizeof(ctx->endtime)); + if (IS_ERR(p)) + goto out_err; + p = simple_get_bytes(p, end, &ctx->seq_send64, sizeof(ctx->seq_send64)); + if (IS_ERR(p)) + goto out_err; + /* set seq_send for use by "older" enctypes */ + ctx->seq_send = ctx->seq_send64; + if (ctx->seq_send64 != ctx->seq_send) { + dprintk("%s: seq_send64 %lx, seq_send %x overflow?\n", __func__, + (long unsigned)ctx->seq_send64, ctx->seq_send); + goto out_err; + } + p = simple_get_bytes(p, end, &ctx->enctype, sizeof(ctx->enctype)); + if (IS_ERR(p)) + goto out_err; + /* Map ENCTYPE_DES3_CBC_SHA1 to ENCTYPE_DES3_CBC_RAW */ + if (ctx->enctype == ENCTYPE_DES3_CBC_SHA1) + ctx->enctype = ENCTYPE_DES3_CBC_RAW; + ctx->gk5e = get_gss_krb5_enctype(ctx->enctype); + if (ctx->gk5e == NULL) { + dprintk("gss_kerberos_mech: unsupported krb5 enctype %u\n", + ctx->enctype); + p = ERR_PTR(-EINVAL); + goto out_err; + } + keylen = ctx->gk5e->keylength; + + p = simple_get_bytes(p, end, ctx->Ksess, keylen); + if (IS_ERR(p)) + goto out_err; + + if (p != end) { + p = ERR_PTR(-EINVAL); + goto out_err; + } + + ctx->mech_used.data = kmemdup(gss_kerberos_mech.gm_oid.data, + gss_kerberos_mech.gm_oid.len, gfp_mask); + if (unlikely(ctx->mech_used.data == NULL)) { + p = ERR_PTR(-ENOMEM); + goto out_err; + } + ctx->mech_used.len = gss_kerberos_mech.gm_oid.len; + + switch (ctx->enctype) { + case ENCTYPE_DES3_CBC_RAW: + return context_derive_keys_des3(ctx, gfp_mask); + case ENCTYPE_ARCFOUR_HMAC: + return context_derive_keys_rc4(ctx); + case ENCTYPE_AES128_CTS_HMAC_SHA1_96: + case ENCTYPE_AES256_CTS_HMAC_SHA1_96: + return context_derive_keys_new(ctx, gfp_mask); + default: + return -EINVAL; + } + +out_err: + return PTR_ERR(p); +} + +static int +gss_import_sec_context_kerberos(const void *p, size_t len, + struct gss_ctx *ctx_id, + gfp_t gfp_mask) +{ + const void *end = (const void *)((const char *)p + len); + struct krb5_ctx *ctx; + int ret; + + ctx = kzalloc(sizeof(*ctx), gfp_mask); + if (ctx == NULL) + return -ENOMEM; + + if (len == 85) + ret = gss_import_v1_context(p, end, ctx); + else + ret = gss_import_v2_context(p, end, ctx, gfp_mask); + + if (ret == 0) + ctx_id->internal_ctx_id = ctx; + else + kfree(ctx); + + dprintk("RPC: %s: returning %d\n", __func__, ret); + return ret; +} + static void gss_delete_sec_context_kerberos(void *internal_ctx) { struct krb5_ctx *kctx = internal_ctx; crypto_free_blkcipher(kctx->seq); crypto_free_blkcipher(kctx->enc); + crypto_free_blkcipher(kctx->acceptor_enc); + crypto_free_blkcipher(kctx->initiator_enc); + crypto_free_blkcipher(kctx->acceptor_enc_aux); + crypto_free_blkcipher(kctx->initiator_enc_aux); kfree(kctx->mech_used.data); kfree(kctx); } @@ -241,6 +744,7 @@ static struct gss_api_mech gss_kerberos_mech = { .gm_ops = &gss_kerberos_ops, .gm_pf_num = ARRAY_SIZE(gss_kerberos_pfs), .gm_pfs = gss_kerberos_pfs, + .gm_upcall_enctypes = "enctypes=18,17,16,23,3,1,2 ", }; static int __init init_kerberos_module(void) |