/* * Copyright (c) 1997 - 2008 Kungliga Tekniska Högskolan * (Royal Institute of Technology, Stockholm, Sweden). * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * 3. Neither the name of the Institute nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include "krb5_locl.h" struct _krb5_key_usage { unsigned usage; struct _krb5_key_data key; }; #ifndef HEIMDAL_SMALLER #define DES3_OLD_ENCTYPE 1 #endif static krb5_error_code _get_derived_key(krb5_context, krb5_crypto, unsigned, struct _krb5_key_data**); static struct _krb5_key_data *_new_derived_key(krb5_crypto crypto, unsigned usage); static void free_key_schedule(krb5_context, struct _krb5_key_data *, struct _krb5_encryption_type *); /* * Converts etype to a user readable string and sets as a side effect * the krb5_error_message containing this string. Returns * KRB5_PROG_ETYPE_NOSUPP in not the conversion of the etype failed in * which case the error code of the etype convesion is returned. */ static krb5_error_code unsupported_enctype(krb5_context context, krb5_enctype etype) { krb5_error_code ret; char *name; ret = krb5_enctype_to_string(context, etype, &name); if (ret) return ret; krb5_set_error_message(context, KRB5_PROG_ETYPE_NOSUPP, N_("Encryption type %s not supported", ""), name); free(name); return KRB5_PROG_ETYPE_NOSUPP; } /* * */ KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL krb5_enctype_keysize(krb5_context context, krb5_enctype type, size_t *keysize) { struct _krb5_encryption_type *et = _krb5_find_enctype(type); if(et == NULL) { return unsupported_enctype (context, type); } *keysize = et->keytype->size; return 0; } KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL krb5_enctype_keybits(krb5_context context, krb5_enctype type, size_t *keybits) { struct _krb5_encryption_type *et = _krb5_find_enctype(type); if(et == NULL) { return unsupported_enctype (context, type); } *keybits = et->keytype->bits; return 0; } KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL krb5_generate_random_keyblock(krb5_context context, krb5_enctype type, krb5_keyblock *key) { krb5_error_code ret; struct _krb5_encryption_type *et = _krb5_find_enctype(type); if(et == NULL) { return unsupported_enctype (context, type); } ret = krb5_data_alloc(&key->keyvalue, et->keytype->size); if(ret) return ret; key->keytype = type; if(et->keytype->random_key) (*et->keytype->random_key)(context, key); else krb5_generate_random_block(key->keyvalue.data, key->keyvalue.length); return 0; } static krb5_error_code _key_schedule(krb5_context context, struct _krb5_key_data *key) { krb5_error_code ret; struct _krb5_encryption_type *et = _krb5_find_enctype(key->key->keytype); struct _krb5_key_type *kt; if (et == NULL) { return unsupported_enctype (context, key->key->keytype); } kt = et->keytype; if(kt->schedule == NULL) return 0; if (key->schedule != NULL) return 0; ALLOC(key->schedule, 1); if(key->schedule == NULL) { krb5_set_error_message(context, ENOMEM, N_("malloc: out of memory", "")); return ENOMEM; } ret = krb5_data_alloc(key->schedule, kt->schedule_size); if(ret) { free(key->schedule); key->schedule = NULL; return ret; } (*kt->schedule)(context, kt, key); return 0; } /************************************************************ * * ************************************************************/ static krb5_error_code SHA1_checksum(krb5_context context, struct _krb5_key_data *key, const void *data, size_t len, unsigned usage, Checksum *C) { if (EVP_Digest(data, len, C->checksum.data, NULL, EVP_sha1(), NULL) != 1) krb5_abortx(context, "sha1 checksum failed"); return 0; } /* HMAC according to RFC2104 */ krb5_error_code _krb5_internal_hmac(krb5_context context, struct _krb5_checksum_type *cm, const void *data, size_t len, unsigned usage, struct _krb5_key_data *keyblock, Checksum *result) { unsigned char *ipad, *opad; unsigned char *key; size_t key_len; size_t i; ipad = malloc(cm->blocksize + len); if (ipad == NULL) return ENOMEM; opad = malloc(cm->blocksize + cm->checksumsize); if (opad == NULL) { free(ipad); return ENOMEM; } memset(ipad, 0x36, cm->blocksize); memset(opad, 0x5c, cm->blocksize); if(keyblock->key->keyvalue.length > cm->blocksize){ (*cm->checksum)(context, keyblock, keyblock->key->keyvalue.data, keyblock->key->keyvalue.length, usage, result); key = result->checksum.data; key_len = result->checksum.length; } else { key = keyblock->key->keyvalue.data; key_len = keyblock->key->keyvalue.length; } for(i = 0; i < key_len; i++){ ipad[i] ^= key[i]; opad[i] ^= key[i]; } memcpy(ipad + cm->blocksize, data, len); (*cm->checksum)(context, keyblock, ipad, cm->blocksize + len, usage, result); memcpy(opad + cm->blocksize, result->checksum.data, result->checksum.length); (*cm->checksum)(context, keyblock, opad, cm->blocksize + cm->checksumsize, usage, result); memset(ipad, 0, cm->blocksize + len); free(ipad); memset(opad, 0, cm->blocksize + cm->checksumsize); free(opad); return 0; } KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL krb5_hmac(krb5_context context, krb5_cksumtype cktype, const void *data, size_t len, unsigned usage, krb5_keyblock *key, Checksum *result) { struct _krb5_checksum_type *c = _krb5_find_checksum(cktype); struct _krb5_key_data kd; krb5_error_code ret; if (c == NULL) { krb5_set_error_message (context, KRB5_PROG_SUMTYPE_NOSUPP, N_("checksum type %d not supported", ""), cktype); return KRB5_PROG_SUMTYPE_NOSUPP; } kd.key = key; kd.schedule = NULL; ret = _krb5_internal_hmac(context, c, data, len, usage, &kd, result); if (kd.schedule) krb5_free_data(context, kd.schedule); return ret; } krb5_error_code _krb5_SP_HMAC_SHA1_checksum(krb5_context context, struct _krb5_key_data *key, const void *data, size_t len, unsigned usage, Checksum *result) { struct _krb5_checksum_type *c = _krb5_find_checksum(CKSUMTYPE_SHA1); Checksum res; char sha1_data[20]; krb5_error_code ret; res.checksum.data = sha1_data; res.checksum.length = sizeof(sha1_data); ret = _krb5_internal_hmac(context, c, data, len, usage, key, &res); if (ret) krb5_abortx(context, "hmac failed"); memcpy(result->checksum.data, res.checksum.data, result->checksum.length); return 0; } struct _krb5_checksum_type _krb5_checksum_sha1 = { CKSUMTYPE_SHA1, "sha1", 64, 20, F_CPROOF, SHA1_checksum, NULL }; struct _krb5_checksum_type * _krb5_find_checksum(krb5_cksumtype type) { int i; for(i = 0; i < _krb5_num_checksums; i++) if(_krb5_checksum_types[i]->type == type) return _krb5_checksum_types[i]; return NULL; } static krb5_error_code get_checksum_key(krb5_context context, krb5_crypto crypto, unsigned usage, /* not krb5_key_usage */ struct _krb5_checksum_type *ct, struct _krb5_key_data **key) { krb5_error_code ret = 0; if(ct->flags & F_DERIVED) ret = _get_derived_key(context, crypto, usage, key); else if(ct->flags & F_VARIANT) { size_t i; *key = _new_derived_key(crypto, 0xff/* KRB5_KU_RFC1510_VARIANT */); if(*key == NULL) { krb5_set_error_message(context, ENOMEM, N_("malloc: out of memory", "")); return ENOMEM; } ret = krb5_copy_keyblock(context, crypto->key.key, &(*key)->key); if(ret) return ret; for(i = 0; i < (*key)->key->keyvalue.length; i++) ((unsigned char*)(*key)->key->keyvalue.data)[i] ^= 0xF0; } else { *key = &crypto->key; } if(ret == 0) ret = _key_schedule(context, *key); return ret; } static krb5_error_code create_checksum (krb5_context context, struct _krb5_checksum_type *ct, krb5_crypto crypto, unsigned usage, void *data, size_t len, Checksum *result) { krb5_error_code ret; struct _krb5_key_data *dkey; int keyed_checksum; if (ct->flags & F_DISABLED) { krb5_clear_error_message (context); return KRB5_PROG_SUMTYPE_NOSUPP; } keyed_checksum = (ct->flags & F_KEYED) != 0; if(keyed_checksum && crypto == NULL) { krb5_set_error_message (context, KRB5_PROG_SUMTYPE_NOSUPP, N_("Checksum type %s is keyed but no " "crypto context (key) was passed in", ""), ct->name); return KRB5_PROG_SUMTYPE_NOSUPP; /* XXX */ } if(keyed_checksum) { ret = get_checksum_key(context, crypto, usage, ct, &dkey); if (ret) return ret; } else dkey = NULL; result->cksumtype = ct->type; ret = krb5_data_alloc(&result->checksum, ct->checksumsize); if (ret) return (ret); return (*ct->checksum)(context, dkey, data, len, usage, result); } static int arcfour_checksum_p(struct _krb5_checksum_type *ct, krb5_crypto crypto) { return (ct->type == CKSUMTYPE_HMAC_MD5) && (crypto->key.key->keytype == KEYTYPE_ARCFOUR); } KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL krb5_create_checksum(krb5_context context, krb5_crypto crypto, krb5_key_usage usage, int type, void *data, size_t len, Checksum *result) { struct _krb5_checksum_type *ct = NULL; unsigned keyusage; /* type 0 -> pick from crypto */ if (type) { ct = _krb5_find_checksum(type); } else if (crypto) { ct = crypto->et->keyed_checksum; if (ct == NULL) ct = crypto->et->checksum; } if(ct == NULL) { krb5_set_error_message (context, KRB5_PROG_SUMTYPE_NOSUPP, N_("checksum type %d not supported", ""), type); return KRB5_PROG_SUMTYPE_NOSUPP; } if (arcfour_checksum_p(ct, crypto)) { keyusage = usage; _krb5_usage2arcfour(context, &keyusage); } else keyusage = CHECKSUM_USAGE(usage); return create_checksum(context, ct, crypto, keyusage, data, len, result); } static krb5_error_code verify_checksum(krb5_context context, krb5_crypto crypto, unsigned usage, /* not krb5_key_usage */ void *data, size_t len, Checksum *cksum) { krb5_error_code ret; struct _krb5_key_data *dkey; int keyed_checksum; Checksum c; struct _krb5_checksum_type *ct; ct = _krb5_find_checksum(cksum->cksumtype); if (ct == NULL || (ct->flags & F_DISABLED)) { krb5_set_error_message (context, KRB5_PROG_SUMTYPE_NOSUPP, N_("checksum type %d not supported", ""), cksum->cksumtype); return KRB5_PROG_SUMTYPE_NOSUPP; } if(ct->checksumsize != cksum->checksum.length) { krb5_clear_error_message (context); krb5_set_error_message(context, KRB5KRB_AP_ERR_BAD_INTEGRITY, N_("Decrypt integrity check failed for checksum type %s, " "length was %u, expected %u", ""), ct->name, (unsigned)cksum->checksum.length, (unsigned)ct->checksumsize); return KRB5KRB_AP_ERR_BAD_INTEGRITY; /* XXX */ } keyed_checksum = (ct->flags & F_KEYED) != 0; if(keyed_checksum) { struct _krb5_checksum_type *kct; if (crypto == NULL) { krb5_set_error_message(context, KRB5_PROG_SUMTYPE_NOSUPP, N_("Checksum type %s is keyed but no " "crypto context (key) was passed in", ""), ct->name); return KRB5_PROG_SUMTYPE_NOSUPP; /* XXX */ } kct = crypto->et->keyed_checksum; if (kct != NULL && kct->type != ct->type) { krb5_set_error_message(context, KRB5_PROG_SUMTYPE_NOSUPP, N_("Checksum type %s is keyed, but " "the key type %s passed didnt have that checksum " "type as the keyed type", ""), ct->name, crypto->et->name); return KRB5_PROG_SUMTYPE_NOSUPP; /* XXX */ } ret = get_checksum_key(context, crypto, usage, ct, &dkey); if (ret) return ret; } else dkey = NULL; /* * If checksum have a verify function, lets use that instead of * calling ->checksum and then compare result. */ if(ct->verify) { ret = (*ct->verify)(context, dkey, data, len, usage, cksum); if (ret) krb5_set_error_message(context, ret, N_("Decrypt integrity check failed for checksum " "type %s, key type %s", ""), ct->name, (crypto != NULL)? crypto->et->name : "(none)"); return ret; } ret = krb5_data_alloc (&c.checksum, ct->checksumsize); if (ret) return ret; ret = (*ct->checksum)(context, dkey, data, len, usage, &c); if (ret) { krb5_data_free(&c.checksum); return ret; } if(krb5_data_ct_cmp(&c.checksum, &cksum->checksum) != 0) { ret = KRB5KRB_AP_ERR_BAD_INTEGRITY; krb5_set_error_message(context, ret, N_("Decrypt integrity check failed for checksum " "type %s, key type %s", ""), ct->name, crypto ? crypto->et->name : "(unkeyed)"); } else { ret = 0; } krb5_data_free (&c.checksum); return ret; } KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL krb5_verify_checksum(krb5_context context, krb5_crypto crypto, krb5_key_usage usage, void *data, size_t len, Checksum *cksum) { struct _krb5_checksum_type *ct; unsigned keyusage; ct = _krb5_find_checksum(cksum->cksumtype); if(ct == NULL) { krb5_set_error_message (context, KRB5_PROG_SUMTYPE_NOSUPP, N_("checksum type %d not supported", ""), cksum->cksumtype); return KRB5_PROG_SUMTYPE_NOSUPP; } if (arcfour_checksum_p(ct, crypto)) { keyusage = usage; _krb5_usage2arcfour(context, &keyusage); } else keyusage = CHECKSUM_USAGE(usage); return verify_checksum(context, crypto, keyusage, data, len, cksum); } KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL krb5_crypto_get_checksum_type(krb5_context context, krb5_crypto crypto, krb5_cksumtype *type) { struct _krb5_checksum_type *ct = NULL; if (crypto != NULL) { ct = crypto->et->keyed_checksum; if (ct == NULL) ct = crypto->et->checksum; } if (ct == NULL) { krb5_set_error_message (context, KRB5_PROG_SUMTYPE_NOSUPP, N_("checksum type not found", "")); return KRB5_PROG_SUMTYPE_NOSUPP; } *type = ct->type; return 0; } KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL krb5_checksumsize(krb5_context context, krb5_cksumtype type, size_t *size) { struct _krb5_checksum_type *ct = _krb5_find_checksum(type); if(ct == NULL) { krb5_set_error_message (context, KRB5_PROG_SUMTYPE_NOSUPP, N_("checksum type %d not supported", ""), type); return KRB5_PROG_SUMTYPE_NOSUPP; } *size = ct->checksumsize; return 0; } KRB5_LIB_FUNCTION krb5_boolean KRB5_LIB_CALL krb5_checksum_is_keyed(krb5_context context, krb5_cksumtype type) { struct _krb5_checksum_type *ct = _krb5_find_checksum(type); if(ct == NULL) { if (context) krb5_set_error_message (context, KRB5_PROG_SUMTYPE_NOSUPP, N_("checksum type %d not supported", ""), type); return KRB5_PROG_SUMTYPE_NOSUPP; } return ct->flags & F_KEYED; } KRB5_LIB_FUNCTION krb5_boolean KRB5_LIB_CALL krb5_checksum_is_collision_proof(krb5_context context, krb5_cksumtype type) { struct _krb5_checksum_type *ct = _krb5_find_checksum(type); if(ct == NULL) { if (context) krb5_set_error_message (context, KRB5_PROG_SUMTYPE_NOSUPP, N_("checksum type %d not supported", ""), type); return KRB5_PROG_SUMTYPE_NOSUPP; } return ct->flags & F_CPROOF; } KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL krb5_checksum_disable(krb5_context context, krb5_cksumtype type) { struct _krb5_checksum_type *ct = _krb5_find_checksum(type); if(ct == NULL) { if (context) krb5_set_error_message (context, KRB5_PROG_SUMTYPE_NOSUPP, N_("checksum type %d not supported", ""), type); return KRB5_PROG_SUMTYPE_NOSUPP; } ct->flags |= F_DISABLED; return 0; } /************************************************************ * * ************************************************************/ struct _krb5_encryption_type * _krb5_find_enctype(krb5_enctype type) { int i; for(i = 0; i < _krb5_num_etypes; i++) if(_krb5_etypes[i]->type == type) return _krb5_etypes[i]; return NULL; } KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL krb5_enctype_to_string(krb5_context context, krb5_enctype etype, char **string) { struct _krb5_encryption_type *e; e = _krb5_find_enctype(etype); if(e == NULL) { krb5_set_error_message (context, KRB5_PROG_ETYPE_NOSUPP, N_("encryption type %d not supported", ""), etype); *string = NULL; return KRB5_PROG_ETYPE_NOSUPP; } *string = strdup(e->name); if(*string == NULL) { krb5_set_error_message(context, ENOMEM, N_("malloc: out of memory", "")); return ENOMEM; } return 0; } KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL krb5_string_to_enctype(krb5_context context, const char *string, krb5_enctype *etype) { int i; for(i = 0; i < _krb5_num_etypes; i++) if(strcasecmp(_krb5_etypes[i]->name, string) == 0){ *etype = _krb5_etypes[i]->type; return 0; } krb5_set_error_message (context, KRB5_PROG_ETYPE_NOSUPP, N_("encryption type %s not supported", ""), string); return KRB5_PROG_ETYPE_NOSUPP; } KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL krb5_enctype_to_keytype(krb5_context context, krb5_enctype etype, krb5_keytype *keytype) { struct _krb5_encryption_type *e = _krb5_find_enctype(etype); if(e == NULL) { return unsupported_enctype (context, etype); } *keytype = e->keytype->type; /* XXX */ return 0; } /** * Check if a enctype is valid, return 0 if it is. * * @param context Kerberos context * @param etype enctype to check if its valid or not * * @return Return an error code for an failure or 0 on success (enctype valid). * @ingroup krb5_crypto */ KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL krb5_enctype_valid(krb5_context context, krb5_enctype etype) { struct _krb5_encryption_type *e = _krb5_find_enctype(etype); if(e && (e->flags & F_DISABLED) == 0) return 0; if (context == NULL) return KRB5_PROG_ETYPE_NOSUPP; if(e == NULL) { return unsupported_enctype (context, etype); } /* Must be (e->flags & F_DISABLED) */ krb5_set_error_message (context, KRB5_PROG_ETYPE_NOSUPP, N_("encryption type %s is disabled", ""), e->name); return KRB5_PROG_ETYPE_NOSUPP; } /** * Return the coresponding encryption type for a checksum type. * * @param context Kerberos context * @param ctype The checksum type to get the result enctype for * @param etype The returned encryption, when the matching etype is * not found, etype is set to ETYPE_NULL. * * @return Return an error code for an failure or 0 on success. * @ingroup krb5_crypto */ KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL krb5_cksumtype_to_enctype(krb5_context context, krb5_cksumtype ctype, krb5_enctype *etype) { int i; *etype = ETYPE_NULL; for(i = 0; i < _krb5_num_etypes; i++) { if(_krb5_etypes[i]->keyed_checksum && _krb5_etypes[i]->keyed_checksum->type == ctype) { *etype = _krb5_etypes[i]->type; return 0; } } krb5_set_error_message (context, KRB5_PROG_SUMTYPE_NOSUPP, N_("checksum type %d not supported", ""), (int)ctype); return KRB5_PROG_SUMTYPE_NOSUPP; } KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL krb5_cksumtype_valid(krb5_context context, krb5_cksumtype ctype) { struct _krb5_checksum_type *c = _krb5_find_checksum(ctype); if (c == NULL) { krb5_set_error_message (context, KRB5_PROG_SUMTYPE_NOSUPP, N_("checksum type %d not supported", ""), ctype); return KRB5_PROG_SUMTYPE_NOSUPP; } if (c->flags & F_DISABLED) { krb5_set_error_message (context, KRB5_PROG_SUMTYPE_NOSUPP, N_("checksum type %s is disabled", ""), c->name); return KRB5_PROG_SUMTYPE_NOSUPP; } return 0; } static krb5_boolean derived_crypto(krb5_context context, krb5_crypto crypto) { return (crypto->et->flags & F_DERIVED) != 0; } static krb5_boolean special_crypto(krb5_context context, krb5_crypto crypto) { return (crypto->et->flags & F_SPECIAL) != 0; } #define CHECKSUMSIZE(C) ((C)->checksumsize) #define CHECKSUMTYPE(C) ((C)->type) static krb5_error_code encrypt_internal_derived(krb5_context context, krb5_crypto crypto, unsigned usage, const void *data, size_t len, krb5_data *result, void *ivec) { size_t sz, block_sz, checksum_sz, total_sz; Checksum cksum; unsigned char *p, *q; krb5_error_code ret; struct _krb5_key_data *dkey; const struct _krb5_encryption_type *et = crypto->et; checksum_sz = CHECKSUMSIZE(et->keyed_checksum); sz = et->confoundersize + len; block_sz = (sz + et->padsize - 1) &~ (et->padsize - 1); /* pad */ total_sz = block_sz + checksum_sz; p = calloc(1, total_sz); if(p == NULL) { krb5_set_error_message(context, ENOMEM, N_("malloc: out of memory", "")); return ENOMEM; } q = p; krb5_generate_random_block(q, et->confoundersize); /* XXX */ q += et->confoundersize; memcpy(q, data, len); ret = create_checksum(context, et->keyed_checksum, crypto, INTEGRITY_USAGE(usage), p, block_sz, &cksum); if(ret == 0 && cksum.checksum.length != checksum_sz) { free_Checksum (&cksum); krb5_clear_error_message (context); ret = KRB5_CRYPTO_INTERNAL; } if(ret) goto fail; memcpy(p + block_sz, cksum.checksum.data, cksum.checksum.length); free_Checksum (&cksum); ret = _get_derived_key(context, crypto, ENCRYPTION_USAGE(usage), &dkey); if(ret) goto fail; ret = _key_schedule(context, dkey); if(ret) goto fail; ret = (*et->encrypt)(context, dkey, p, block_sz, 1, usage, ivec); if (ret) goto fail; result->data = p; result->length = total_sz; return 0; fail: memset(p, 0, total_sz); free(p); return ret; } static krb5_error_code encrypt_internal(krb5_context context, krb5_crypto crypto, const void *data, size_t len, krb5_data *result, void *ivec) { size_t sz, block_sz, checksum_sz; Checksum cksum; unsigned char *p, *q; krb5_error_code ret; const struct _krb5_encryption_type *et = crypto->et; checksum_sz = CHECKSUMSIZE(et->checksum); sz = et->confoundersize + checksum_sz + len; block_sz = (sz + et->padsize - 1) &~ (et->padsize - 1); /* pad */ p = calloc(1, block_sz); if(p == NULL) { krb5_set_error_message(context, ENOMEM, N_("malloc: out of memory", "")); return ENOMEM; } q = p; krb5_generate_random_block(q, et->confoundersize); /* XXX */ q += et->confoundersize; memset(q, 0, checksum_sz); q += checksum_sz; memcpy(q, data, len); ret = create_checksum(context, et->checksum, crypto, 0, p, block_sz, &cksum); if(ret == 0 && cksum.checksum.length != checksum_sz) { krb5_clear_error_message (context); free_Checksum(&cksum); ret = KRB5_CRYPTO_INTERNAL; } if(ret) goto fail; memcpy(p + et->confoundersize, cksum.checksum.data, cksum.checksum.length); free_Checksum(&cksum); ret = _key_schedule(context, &crypto->key); if(ret) goto fail; ret = (*et->encrypt)(context, &crypto->key, p, block_sz, 1, 0, ivec); if (ret) { memset(p, 0, block_sz); free(p); return ret; } result->data = p; result->length = block_sz; return 0; fail: memset(p, 0, block_sz); free(p); return ret; } static krb5_error_code encrypt_internal_special(krb5_context context, krb5_crypto crypto, int usage, const void *data, size_t len, krb5_data *result, void *ivec) { struct _krb5_encryption_type *et = crypto->et; size_t cksum_sz = CHECKSUMSIZE(et->checksum); size_t sz = len + cksum_sz + et->confoundersize; char *tmp, *p; krb5_error_code ret; tmp = malloc (sz); if (tmp == NULL) { krb5_set_error_message(context, ENOMEM, N_("malloc: out of memory", "")); return ENOMEM; } p = tmp; memset (p, 0, cksum_sz); p += cksum_sz; krb5_generate_random_block(p, et->confoundersize); p += et->confoundersize; memcpy (p, data, len); ret = (*et->encrypt)(context, &crypto->key, tmp, sz, TRUE, usage, ivec); if (ret) { memset(tmp, 0, sz); free(tmp); return ret; } result->data = tmp; result->length = sz; return 0; } static krb5_error_code decrypt_internal_derived(krb5_context context, krb5_crypto crypto, unsigned usage, void *data, size_t len, krb5_data *result, void *ivec) { size_t checksum_sz; Checksum cksum; unsigned char *p; krb5_error_code ret; struct _krb5_key_data *dkey; struct _krb5_encryption_type *et = crypto->et; unsigned long l; checksum_sz = CHECKSUMSIZE(et->keyed_checksum); if (len < checksum_sz + et->confoundersize) { krb5_set_error_message(context, KRB5_BAD_MSIZE, N_("Encrypted data shorter then " "checksum + confunder", "")); return KRB5_BAD_MSIZE; } if (((len - checksum_sz) % et->padsize) != 0) { krb5_clear_error_message(context); return KRB5_BAD_MSIZE; } p = malloc(len); if(len != 0 && p == NULL) { krb5_set_error_message(context, ENOMEM, N_("malloc: out of memory", "")); return ENOMEM; } memcpy(p, data, len); len -= checksum_sz; ret = _get_derived_key(context, crypto, ENCRYPTION_USAGE(usage), &dkey); if(ret) { free(p); return ret; } ret = _key_schedule(context, dkey); if(ret) { free(p); return ret; } ret = (*et->encrypt)(context, dkey, p, len, 0, usage, ivec); if (ret) { free(p); return ret; } cksum.checksum.data = p + len; cksum.checksum.length = checksum_sz; cksum.cksumtype = CHECKSUMTYPE(et->keyed_checksum); ret = verify_checksum(context, crypto, INTEGRITY_USAGE(usage), p, len, &cksum); if(ret) { free(p); return ret; } l = len - et->confoundersize; memmove(p, p + et->confoundersize, l); result->data = realloc(p, l); if(result->data == NULL && l != 0) { free(p); krb5_set_error_message(context, ENOMEM, N_("malloc: out of memory", "")); return ENOMEM; } result->length = l; return 0; } static krb5_error_code decrypt_internal(krb5_context context, krb5_crypto crypto, void *data, size_t len, krb5_data *result, void *ivec) { krb5_error_code ret; unsigned char *p; Checksum cksum; size_t checksum_sz, l; struct _krb5_encryption_type *et = crypto->et; if ((len % et->padsize) != 0) { krb5_clear_error_message(context); return KRB5_BAD_MSIZE; } checksum_sz = CHECKSUMSIZE(et->checksum); if (len < checksum_sz + et->confoundersize) { krb5_set_error_message(context, KRB5_BAD_MSIZE, N_("Encrypted data shorter then " "checksum + confunder", "")); return KRB5_BAD_MSIZE; } p = malloc(len); if(len != 0 && p == NULL) { krb5_set_error_message(context, ENOMEM, N_("malloc: out of memory", "")); return ENOMEM; } memcpy(p, data, len); ret = _key_schedule(context, &crypto->key); if(ret) { free(p); return ret; } ret = (*et->encrypt)(context, &crypto->key, p, len, 0, 0, ivec); if (ret) { free(p); return ret; } ret = krb5_data_copy(&cksum.checksum, p + et->confoundersize, checksum_sz); if(ret) { free(p); return ret; } memset(p + et->confoundersize, 0, checksum_sz); cksum.cksumtype = CHECKSUMTYPE(et->checksum); ret = verify_checksum(context, NULL, 0, p, len, &cksum); free_Checksum(&cksum); if(ret) { free(p); return ret; } l = len - et->confoundersize - checksum_sz; memmove(p, p + et->confoundersize + checksum_sz, l); result->data = realloc(p, l); if(result->data == NULL && l != 0) { free(p); krb5_set_error_message(context, ENOMEM, N_("malloc: out of memory", "")); return ENOMEM; } result->length = l; return 0; } static krb5_error_code decrypt_internal_special(krb5_context context, krb5_crypto crypto, int usage, void *data, size_t len, krb5_data *result, void *ivec) { struct _krb5_encryption_type *et = crypto->et; size_t cksum_sz = CHECKSUMSIZE(et->checksum); size_t sz = len - cksum_sz - et->confoundersize; unsigned char *p; krb5_error_code ret; if ((len % et->padsize) != 0) { krb5_clear_error_message(context); return KRB5_BAD_MSIZE; } if (len < cksum_sz + et->confoundersize) { krb5_set_error_message(context, KRB5_BAD_MSIZE, N_("Encrypted data shorter then " "checksum + confunder", "")); return KRB5_BAD_MSIZE; } p = malloc (len); if (p == NULL) { krb5_set_error_message(context, ENOMEM, N_("malloc: out of memory", "")); return ENOMEM; } memcpy(p, data, len); ret = (*et->encrypt)(context, &crypto->key, p, len, FALSE, usage, ivec); if (ret) { free(p); return ret; } memmove (p, p + cksum_sz + et->confoundersize, sz); result->data = realloc(p, sz); if(result->data == NULL && sz != 0) { free(p); krb5_set_error_message(context, ENOMEM, N_("malloc: out of memory", "")); return ENOMEM; } result->length = sz; return 0; } static krb5_crypto_iov * find_iv(krb5_crypto_iov *data, size_t num_data, unsigned type) { size_t i; for (i = 0; i < num_data; i++) if (data[i].flags == type) return &data[i]; return NULL; } /** * Inline encrypt a kerberos message * * @param context Kerberos context * @param crypto Kerberos crypto context * @param usage Key usage for this buffer * @param data array of buffers to process * @param num_data length of array * @param ivec initial cbc/cts vector * * @return Return an error code or 0. * @ingroup krb5_crypto * * Kerberos encrypted data look like this: * * 1. KRB5_CRYPTO_TYPE_HEADER * 2. array [1,...] KRB5_CRYPTO_TYPE_DATA and array [0,...] * KRB5_CRYPTO_TYPE_SIGN_ONLY in any order, however the receiver * have to aware of the order. KRB5_CRYPTO_TYPE_SIGN_ONLY is * commonly used headers and trailers. * 3. KRB5_CRYPTO_TYPE_PADDING, at least on padsize long if padsize > 1 * 4. KRB5_CRYPTO_TYPE_TRAILER */ KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL krb5_encrypt_iov_ivec(krb5_context context, krb5_crypto crypto, unsigned usage, krb5_crypto_iov *data, int num_data, void *ivec) { size_t headersz, trailersz, len; int i; size_t sz, block_sz, pad_sz; Checksum cksum; unsigned char *p, *q; krb5_error_code ret; struct _krb5_key_data *dkey; const struct _krb5_encryption_type *et = crypto->et; krb5_crypto_iov *tiv, *piv, *hiv; if (num_data < 0) { krb5_clear_error_message(context); return KRB5_CRYPTO_INTERNAL; } if(!derived_crypto(context, crypto)) { krb5_clear_error_message(context); return KRB5_CRYPTO_INTERNAL; } headersz = et->confoundersize; trailersz = CHECKSUMSIZE(et->keyed_checksum); for (len = 0, i = 0; i < num_data; i++) { if (data[i].flags != KRB5_CRYPTO_TYPE_DATA) continue; len += data[i].data.length; } sz = headersz + len; block_sz = (sz + et->padsize - 1) &~ (et->padsize - 1); /* pad */ pad_sz = block_sz - sz; /* header */ hiv = find_iv(data, num_data, KRB5_CRYPTO_TYPE_HEADER); if (hiv == NULL || hiv->data.length != headersz) return KRB5_BAD_MSIZE; krb5_generate_random_block(hiv->data.data, hiv->data.length); /* padding */ piv = find_iv(data, num_data, KRB5_CRYPTO_TYPE_PADDING); /* its ok to have no TYPE_PADDING if there is no padding */ if (piv == NULL && pad_sz != 0) return KRB5_BAD_MSIZE; if (piv) { if (piv->data.length < pad_sz) return KRB5_BAD_MSIZE; piv->data.length = pad_sz; if (pad_sz) memset(piv->data.data, pad_sz, pad_sz); else piv = NULL; } /* trailer */ tiv = find_iv(data, num_data, KRB5_CRYPTO_TYPE_TRAILER); if (tiv == NULL || tiv->data.length != trailersz) return KRB5_BAD_MSIZE; /* * XXX replace with EVP_Sign? at least make create_checksum an iov * function. * XXX CTS EVP is broken, can't handle multi buffers :( */ len = block_sz; for (i = 0; i < num_data; i++) { if (data[i].flags != KRB5_CRYPTO_TYPE_SIGN_ONLY) continue; len += data[i].data.length; } p = q = malloc(len); memcpy(q, hiv->data.data, hiv->data.length); q += hiv->data.length; for (i = 0; i < num_data; i++) { if (data[i].flags != KRB5_CRYPTO_TYPE_DATA && data[i].flags != KRB5_CRYPTO_TYPE_SIGN_ONLY) continue; memcpy(q, data[i].data.data, data[i].data.length); q += data[i].data.length; } if (piv) memset(q, 0, piv->data.length); ret = create_checksum(context, et->keyed_checksum, crypto, INTEGRITY_USAGE(usage), p, len, &cksum); free(p); if(ret == 0 && cksum.checksum.length != trailersz) { free_Checksum (&cksum); krb5_clear_error_message (context); ret = KRB5_CRYPTO_INTERNAL; } if(ret) return ret; /* save cksum at end */ memcpy(tiv->data.data, cksum.checksum.data, cksum.checksum.length); free_Checksum (&cksum); /* XXX replace with EVP_Cipher */ p = q = malloc(block_sz); if(p == NULL) return ENOMEM; memcpy(q, hiv->data.data, hiv->data.length); q += hiv->data.length; for (i = 0; i < num_data; i++) { if (data[i].flags != KRB5_CRYPTO_TYPE_DATA) continue; memcpy(q, data[i].data.data, data[i].data.length); q += data[i].data.length; } if (piv) memset(q, 0, piv->data.length); ret = _get_derived_key(context, crypto, ENCRYPTION_USAGE(usage), &dkey); if(ret) { free(p); return ret; } ret = _key_schedule(context, dkey); if(ret) { free(p); return ret; } ret = (*et->encrypt)(context, dkey, p, block_sz, 1, usage, ivec); if (ret) { free(p); return ret; } /* now copy data back to buffers */ q = p; memcpy(hiv->data.data, q, hiv->data.length); q += hiv->data.length; for (i = 0; i < num_data; i++) { if (data[i].flags != KRB5_CRYPTO_TYPE_DATA) continue; memcpy(data[i].data.data, q, data[i].data.length); q += data[i].data.length; } if (piv) memcpy(piv->data.data, q, pad_sz); free(p); return ret; } /** * Inline decrypt a Kerberos message. * * @param context Kerberos context * @param crypto Kerberos crypto context * @param usage Key usage for this buffer * @param data array of buffers to process * @param num_data length of array * @param ivec initial cbc/cts vector * * @return Return an error code or 0. * @ingroup krb5_crypto * * 1. KRB5_CRYPTO_TYPE_HEADER * 2. one KRB5_CRYPTO_TYPE_DATA and array [0,...] of KRB5_CRYPTO_TYPE_SIGN_ONLY in * any order, however the receiver have to aware of the * order. KRB5_CRYPTO_TYPE_SIGN_ONLY is commonly used unencrypoted * protocol headers and trailers. The output data will be of same * size as the input data or shorter. */ KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL krb5_decrypt_iov_ivec(krb5_context context, krb5_crypto crypto, unsigned usage, krb5_crypto_iov *data, unsigned int num_data, void *ivec) { unsigned int i; size_t headersz, trailersz, len; Checksum cksum; unsigned char *p, *q; krb5_error_code ret; struct _krb5_key_data *dkey; struct _krb5_encryption_type *et = crypto->et; krb5_crypto_iov *tiv, *hiv; if(!derived_crypto(context, crypto)) { krb5_clear_error_message(context); return KRB5_CRYPTO_INTERNAL; } headersz = et->confoundersize; hiv = find_iv(data, num_data, KRB5_CRYPTO_TYPE_HEADER); if (hiv == NULL || hiv->data.length != headersz) return KRB5_BAD_MSIZE; /* trailer */ trailersz = CHECKSUMSIZE(et->keyed_checksum); tiv = find_iv(data, num_data, KRB5_CRYPTO_TYPE_TRAILER); if (tiv->data.length != trailersz) return KRB5_BAD_MSIZE; /* Find length of data we will decrypt */ len = headersz; for (i = 0; i < num_data; i++) { if (data[i].flags != KRB5_CRYPTO_TYPE_DATA) continue; len += data[i].data.length; } if ((len % et->padsize) != 0) { krb5_clear_error_message(context); return KRB5_BAD_MSIZE; } /* XXX replace with EVP_Cipher */ p = q = malloc(len); if (p == NULL) return ENOMEM; memcpy(q, hiv->data.data, hiv->data.length); q += hiv->data.length; for (i = 0; i < num_data; i++) { if (data[i].flags != KRB5_CRYPTO_TYPE_DATA) continue; memcpy(q, data[i].data.data, data[i].data.length); q += data[i].data.length; } ret = _get_derived_key(context, crypto, ENCRYPTION_USAGE(usage), &dkey); if(ret) { free(p); return ret; } ret = _key_schedule(context, dkey); if(ret) { free(p); return ret; } ret = (*et->encrypt)(context, dkey, p, len, 0, usage, ivec); if (ret) { free(p); return ret; } /* copy data back to buffers */ memcpy(hiv->data.data, p, hiv->data.length); q = p + hiv->data.length; for (i = 0; i < num_data; i++) { if (data[i].flags != KRB5_CRYPTO_TYPE_DATA) continue; memcpy(data[i].data.data, q, data[i].data.length); q += data[i].data.length; } free(p); /* check signature */ for (i = 0; i < num_data; i++) { if (data[i].flags != KRB5_CRYPTO_TYPE_SIGN_ONLY) continue; len += data[i].data.length; } p = q = malloc(len); if (p == NULL) return ENOMEM; memcpy(q, hiv->data.data, hiv->data.length); q += hiv->data.length; for (i = 0; i < num_data; i++) { if (data[i].flags != KRB5_CRYPTO_TYPE_DATA && data[i].flags != KRB5_CRYPTO_TYPE_SIGN_ONLY) continue; memcpy(q, data[i].data.data, data[i].data.length); q += data[i].data.length; } cksum.checksum.data = tiv->data.data; cksum.checksum.length = tiv->data.length; cksum.cksumtype = CHECKSUMTYPE(et->keyed_checksum); ret = verify_checksum(context, crypto, INTEGRITY_USAGE(usage), p, len, &cksum); free(p); return ret; } /** * Create a Kerberos message checksum. * * @param context Kerberos context * @param crypto Kerberos crypto context * @param usage Key usage for this buffer * @param data array of buffers to process * @param num_data length of array * @param type output data * * @return Return an error code or 0. * @ingroup krb5_crypto */ KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL krb5_create_checksum_iov(krb5_context context, krb5_crypto crypto, unsigned usage, krb5_crypto_iov *data, unsigned int num_data, krb5_cksumtype *type) { Checksum cksum; krb5_crypto_iov *civ; krb5_error_code ret; size_t i; size_t len; char *p, *q; if(!derived_crypto(context, crypto)) { krb5_clear_error_message(context); return KRB5_CRYPTO_INTERNAL; } civ = find_iv(data, num_data, KRB5_CRYPTO_TYPE_CHECKSUM); if (civ == NULL) return KRB5_BAD_MSIZE; len = 0; for (i = 0; i < num_data; i++) { if (data[i].flags != KRB5_CRYPTO_TYPE_DATA && data[i].flags != KRB5_CRYPTO_TYPE_SIGN_ONLY) continue; len += data[i].data.length; } p = q = malloc(len); for (i = 0; i < num_data; i++) { if (data[i].flags != KRB5_CRYPTO_TYPE_DATA && data[i].flags != KRB5_CRYPTO_TYPE_SIGN_ONLY) continue; memcpy(q, data[i].data.data, data[i].data.length); q += data[i].data.length; } ret = krb5_create_checksum(context, crypto, usage, 0, p, len, &cksum); free(p); if (ret) return ret; if (type) *type = cksum.cksumtype; if (cksum.checksum.length > civ->data.length) { krb5_set_error_message(context, KRB5_BAD_MSIZE, N_("Checksum larger then input buffer", "")); free_Checksum(&cksum); return KRB5_BAD_MSIZE; } civ->data.length = cksum.checksum.length; memcpy(civ->data.data, cksum.checksum.data, civ->data.length); free_Checksum(&cksum); return 0; } /** * Verify a Kerberos message checksum. * * @param context Kerberos context * @param crypto Kerberos crypto context * @param usage Key usage for this buffer * @param data array of buffers to process * @param num_data length of array * @param type return checksum type if not NULL * * @return Return an error code or 0. * @ingroup krb5_crypto */ KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL krb5_verify_checksum_iov(krb5_context context, krb5_crypto crypto, unsigned usage, krb5_crypto_iov *data, unsigned int num_data, krb5_cksumtype *type) { struct _krb5_encryption_type *et = crypto->et; Checksum cksum; krb5_crypto_iov *civ; krb5_error_code ret; size_t i; size_t len; char *p, *q; if(!derived_crypto(context, crypto)) { krb5_clear_error_message(context); return KRB5_CRYPTO_INTERNAL; } civ = find_iv(data, num_data, KRB5_CRYPTO_TYPE_CHECKSUM); if (civ == NULL) return KRB5_BAD_MSIZE; len = 0; for (i = 0; i < num_data; i++) { if (data[i].flags != KRB5_CRYPTO_TYPE_DATA && data[i].flags != KRB5_CRYPTO_TYPE_SIGN_ONLY) continue; len += data[i].data.length; } p = q = malloc(len); for (i = 0; i < num_data; i++) { if (data[i].flags != KRB5_CRYPTO_TYPE_DATA && data[i].flags != KRB5_CRYPTO_TYPE_SIGN_ONLY) continue; memcpy(q, data[i].data.data, data[i].data.length); q += data[i].data.length; } cksum.cksumtype = CHECKSUMTYPE(et->keyed_checksum); cksum.checksum.length = civ->data.length; cksum.checksum.data = civ->data.data; ret = krb5_verify_checksum(context, crypto, usage, p, len, &cksum); free(p); if (ret == 0 && type) *type = cksum.cksumtype; return ret; } KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL krb5_crypto_length(krb5_context context, krb5_crypto crypto, int type, size_t *len) { if (!derived_crypto(context, crypto)) { krb5_set_error_message(context, EINVAL, "not a derived crypto"); return EINVAL; } switch(type) { case KRB5_CRYPTO_TYPE_EMPTY: *len = 0; return 0; case KRB5_CRYPTO_TYPE_HEADER: *len = crypto->et->blocksize; return 0; case KRB5_CRYPTO_TYPE_DATA: case KRB5_CRYPTO_TYPE_SIGN_ONLY: /* len must already been filled in */ return 0; case KRB5_CRYPTO_TYPE_PADDING: if (crypto->et->padsize > 1) *len = crypto->et->padsize; else *len = 0; return 0; case KRB5_CRYPTO_TYPE_TRAILER: *len = CHECKSUMSIZE(crypto->et->keyed_checksum); return 0; case KRB5_CRYPTO_TYPE_CHECKSUM: if (crypto->et->keyed_checksum) *len = CHECKSUMSIZE(crypto->et->keyed_checksum); else *len = CHECKSUMSIZE(crypto->et->checksum); return 0; } krb5_set_error_message(context, EINVAL, "%d not a supported type", type); return EINVAL; } KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL krb5_crypto_length_iov(krb5_context context, krb5_crypto crypto, krb5_crypto_iov *data, unsigned int num_data) { krb5_error_code ret; size_t i; for (i = 0; i < num_data; i++) { ret = krb5_crypto_length(context, crypto, data[i].flags, &data[i].data.length); if (ret) return ret; } return 0; } KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL krb5_encrypt_ivec(krb5_context context, krb5_crypto crypto, unsigned usage, const void *data, size_t len, krb5_data *result, void *ivec) { if(derived_crypto(context, crypto)) return encrypt_internal_derived(context, crypto, usage, data, len, result, ivec); else if (special_crypto(context, crypto)) return encrypt_internal_special (context, crypto, usage, data, len, result, ivec); else return encrypt_internal(context, crypto, data, len, result, ivec); } KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL krb5_encrypt(krb5_context context, krb5_crypto crypto, unsigned usage, const void *data, size_t len, krb5_data *result) { return krb5_encrypt_ivec(context, crypto, usage, data, len, result, NULL); } KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL krb5_encrypt_EncryptedData(krb5_context context, krb5_crypto crypto, unsigned usage, void *data, size_t len, int kvno, EncryptedData *result) { result->etype = CRYPTO_ETYPE(crypto); if(kvno){ ALLOC(result->kvno, 1); *result->kvno = kvno; }else result->kvno = NULL; return krb5_encrypt(context, crypto, usage, data, len, &result->cipher); } KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL krb5_decrypt_ivec(krb5_context context, krb5_crypto crypto, unsigned usage, void *data, size_t len, krb5_data *result, void *ivec) { if(derived_crypto(context, crypto)) return decrypt_internal_derived(context, crypto, usage, data, len, result, ivec); else if (special_crypto (context, crypto)) return decrypt_internal_special(context, crypto, usage, data, len, result, ivec); else return decrypt_internal(context, crypto, data, len, result, ivec); } KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL krb5_decrypt(krb5_context context, krb5_crypto crypto, unsigned usage, void *data, size_t len, krb5_data *result) { return krb5_decrypt_ivec (context, crypto, usage, data, len, result, NULL); } KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL krb5_decrypt_EncryptedData(krb5_context context, krb5_crypto crypto, unsigned usage, const EncryptedData *e, krb5_data *result) { return krb5_decrypt(context, crypto, usage, e->cipher.data, e->cipher.length, result); } /************************************************************ * * ************************************************************/ krb5_error_code _krb5_derive_key(krb5_context context, struct _krb5_encryption_type *et, struct _krb5_key_data *key, const void *constant, size_t len) { unsigned char *k = NULL; unsigned int nblocks = 0, i; krb5_error_code ret = 0; struct _krb5_key_type *kt = et->keytype; ret = _key_schedule(context, key); if(ret) return ret; if(et->blocksize * 8 < kt->bits || len != et->blocksize) { nblocks = (kt->bits + et->blocksize * 8 - 1) / (et->blocksize * 8); k = malloc(nblocks * et->blocksize); if(k == NULL) { ret = ENOMEM; krb5_set_error_message(context, ret, N_("malloc: out of memory", "")); goto out; } ret = _krb5_n_fold(constant, len, k, et->blocksize); if (ret) { krb5_set_error_message(context, ret, N_("malloc: out of memory", "")); goto out; } for(i = 0; i < nblocks; i++) { if(i > 0) memcpy(k + i * et->blocksize, k + (i - 1) * et->blocksize, et->blocksize); (*et->encrypt)(context, key, k + i * et->blocksize, et->blocksize, 1, 0, NULL); } } else { /* this case is probably broken, but won't be run anyway */ void *c = malloc(len); size_t res_len = (kt->bits + 7) / 8; if(len != 0 && c == NULL) { ret = ENOMEM; krb5_set_error_message(context, ret, N_("malloc: out of memory", "")); goto out; } memcpy(c, constant, len); (*et->encrypt)(context, key, c, len, 1, 0, NULL); k = malloc(res_len); if(res_len != 0 && k == NULL) { free(c); ret = ENOMEM; krb5_set_error_message(context, ret, N_("malloc: out of memory", "")); goto out; } ret = _krb5_n_fold(c, len, k, res_len); free(c); if (ret) { krb5_set_error_message(context, ret, N_("malloc: out of memory", "")); goto out; } } /* XXX keytype dependent post-processing */ switch(kt->type) { case KRB5_ENCTYPE_OLD_DES3_CBC_SHA1: _krb5_DES3_random_to_key(context, key->key, k, nblocks * et->blocksize); break; case KRB5_ENCTYPE_AES128_CTS_HMAC_SHA1_96: case KRB5_ENCTYPE_AES256_CTS_HMAC_SHA1_96: memcpy(key->key->keyvalue.data, k, key->key->keyvalue.length); break; default: ret = KRB5_CRYPTO_INTERNAL; krb5_set_error_message(context, ret, N_("derive_key() called with unknown keytype (%u)", ""), kt->type); break; } out: if (key->schedule) { free_key_schedule(context, key, et); key->schedule = NULL; } if (k) { memset(k, 0, nblocks * et->blocksize); free(k); } return ret; } static struct _krb5_key_data * _new_derived_key(krb5_crypto crypto, unsigned usage) { struct _krb5_key_usage *d = crypto->key_usage; d = realloc(d, (crypto->num_key_usage + 1) * sizeof(*d)); if(d == NULL) return NULL; crypto->key_usage = d; d += crypto->num_key_usage++; memset(d, 0, sizeof(*d)); d->usage = usage; return &d->key; } KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL krb5_derive_key(krb5_context context, const krb5_keyblock *key, krb5_enctype etype, const void *constant, size_t constant_len, krb5_keyblock **derived_key) { krb5_error_code ret; struct _krb5_encryption_type *et; struct _krb5_key_data d; *derived_key = NULL; et = _krb5_find_enctype (etype); if (et == NULL) { return unsupported_enctype (context, etype); } ret = krb5_copy_keyblock(context, key, &d.key); if (ret) return ret; d.schedule = NULL; ret = _krb5_derive_key(context, et, &d, constant, constant_len); if (ret == 0) ret = krb5_copy_keyblock(context, d.key, derived_key); _krb5_free_key_data(context, &d, et); return ret; } static krb5_error_code _get_derived_key(krb5_context context, krb5_crypto crypto, unsigned usage, struct _krb5_key_data **key) { int i; struct _krb5_key_data *d; unsigned char constant[5]; for(i = 0; i < crypto->num_key_usage; i++) if(crypto->key_usage[i].usage == usage) { *key = &crypto->key_usage[i].key; return 0; } d = _new_derived_key(crypto, usage); if(d == NULL) { krb5_set_error_message(context, ENOMEM, N_("malloc: out of memory", "")); return ENOMEM; } krb5_copy_keyblock(context, crypto->key.key, &d->key); _krb5_put_int(constant, usage, 5); _krb5_derive_key(context, crypto->et, d, constant, sizeof(constant)); *key = d; return 0; } /** * Create a crypto context used for all encryption and signature * operation. The encryption type to use is taken from the key, but * can be overridden with the enctype parameter. This can be useful * for encryptions types which is compatiable (DES for example). * * To free the crypto context, use krb5_crypto_destroy(). * * @param context Kerberos context * @param key the key block information with all key data * @param etype the encryption type * @param crypto the resulting crypto context * * @return Return an error code or 0. * * @ingroup krb5_crypto */ KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL krb5_crypto_init(krb5_context context, const krb5_keyblock *key, krb5_enctype etype, krb5_crypto *crypto) { krb5_error_code ret; ALLOC(*crypto, 1); if(*crypto == NULL) { krb5_set_error_message(context, ENOMEM, N_("malloc: out of memory", "")); return ENOMEM; } if(etype == ETYPE_NULL) etype = key->keytype; (*crypto)->et = _krb5_find_enctype(etype); if((*crypto)->et == NULL || ((*crypto)->et->flags & F_DISABLED)) { free(*crypto); *crypto = NULL; return unsupported_enctype(context, etype); } if((*crypto)->et->keytype->size != key->keyvalue.length) { free(*crypto); *crypto = NULL; krb5_set_error_message (context, KRB5_BAD_KEYSIZE, "encryption key has bad length"); return KRB5_BAD_KEYSIZE; } ret = krb5_copy_keyblock(context, key, &(*crypto)->key.key); if(ret) { free(*crypto); *crypto = NULL; return ret; } (*crypto)->key.schedule = NULL; (*crypto)->num_key_usage = 0; (*crypto)->key_usage = NULL; return 0; } static void free_key_schedule(krb5_context context, struct _krb5_key_data *key, struct _krb5_encryption_type *et) { if (et->keytype->cleanup) (*et->keytype->cleanup)(context, key); memset(key->schedule->data, 0, key->schedule->length); krb5_free_data(context, key->schedule); } void _krb5_free_key_data(krb5_context context, struct _krb5_key_data *key, struct _krb5_encryption_type *et) { krb5_free_keyblock(context, key->key); if(key->schedule) { free_key_schedule(context, key, et); key->schedule = NULL; } } static void free_key_usage(krb5_context context, struct _krb5_key_usage *ku, struct _krb5_encryption_type *et) { _krb5_free_key_data(context, &ku->key, et); } /** * Free a crypto context created by krb5_crypto_init(). * * @param context Kerberos context * @param crypto crypto context to free * * @return Return an error code or 0. * * @ingroup krb5_crypto */ KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL krb5_crypto_destroy(krb5_context context, krb5_crypto crypto) { int i; for(i = 0; i < crypto->num_key_usage; i++) free_key_usage(context, &crypto->key_usage[i], crypto->et); free(crypto->key_usage); _krb5_free_key_data(context, &crypto->key, crypto->et); free (crypto); return 0; } /** * Return the blocksize used algorithm referenced by the crypto context * * @param context Kerberos context * @param crypto crypto context to query * @param blocksize the resulting blocksize * * @return Return an error code or 0. * * @ingroup krb5_crypto */ KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL krb5_crypto_getblocksize(krb5_context context, krb5_crypto crypto, size_t *blocksize) { *blocksize = crypto->et->blocksize; return 0; } /** * Return the encryption type used by the crypto context * * @param context Kerberos context * @param crypto crypto context to query * @param enctype the resulting encryption type * * @return Return an error code or 0. * * @ingroup krb5_crypto */ KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL krb5_crypto_getenctype(krb5_context context, krb5_crypto crypto, krb5_enctype *enctype) { *enctype = crypto->et->type; return 0; } /** * Return the padding size used by the crypto context * * @param context Kerberos context * @param crypto crypto context to query * @param padsize the return padding size * * @return Return an error code or 0. * * @ingroup krb5_crypto */ KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL krb5_crypto_getpadsize(krb5_context context, krb5_crypto crypto, size_t *padsize) { *padsize = crypto->et->padsize; return 0; } /** * Return the confounder size used by the crypto context * * @param context Kerberos context * @param crypto crypto context to query * @param confoundersize the returned confounder size * * @return Return an error code or 0. * * @ingroup krb5_crypto */ KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL krb5_crypto_getconfoundersize(krb5_context context, krb5_crypto crypto, size_t *confoundersize) { *confoundersize = crypto->et->confoundersize; return 0; } /** * Disable encryption type * * @param context Kerberos 5 context * @param enctype encryption type to disable * * @return Return an error code or 0. * * @ingroup krb5_crypto */ KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL krb5_enctype_disable(krb5_context context, krb5_enctype enctype) { struct _krb5_encryption_type *et = _krb5_find_enctype(enctype); if(et == NULL) { if (context) krb5_set_error_message (context, KRB5_PROG_ETYPE_NOSUPP, N_("encryption type %d not supported", ""), enctype); return KRB5_PROG_ETYPE_NOSUPP; } et->flags |= F_DISABLED; return 0; } /** * Enable encryption type * * @param context Kerberos 5 context * @param enctype encryption type to enable * * @return Return an error code or 0. * * @ingroup krb5_crypto */ KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL krb5_enctype_enable(krb5_context context, krb5_enctype enctype) { struct _krb5_encryption_type *et = _krb5_find_enctype(enctype); if(et == NULL) { if (context) krb5_set_error_message (context, KRB5_PROG_ETYPE_NOSUPP, N_("encryption type %d not supported", ""), enctype); return KRB5_PROG_ETYPE_NOSUPP; } et->flags &= ~F_DISABLED; return 0; } /** * Enable or disable all weak encryption types * * @param context Kerberos 5 context * @param enable true to enable, false to disable * * @return Return an error code or 0. * * @ingroup krb5_crypto */ KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL krb5_allow_weak_crypto(krb5_context context, krb5_boolean enable) { int i; for(i = 0; i < _krb5_num_etypes; i++) if(_krb5_etypes[i]->flags & F_WEAK) { if(enable) _krb5_etypes[i]->flags &= ~F_DISABLED; else _krb5_etypes[i]->flags |= F_DISABLED; } return 0; } /** * Returns is the encryption is strong or weak * * @param context Kerberos 5 context * @param enctype encryption type to probe * * @return Returns true if encryption type is weak or is not supported. * * @ingroup krb5_crypto */ KRB5_LIB_FUNCTION krb5_boolean KRB5_LIB_CALL krb5_is_enctype_weak(krb5_context context, krb5_enctype enctype) { struct _krb5_encryption_type *et = _krb5_find_enctype(enctype); if(et == NULL || (et->flags & F_WEAK)) return TRUE; return FALSE; } static size_t wrapped_length (krb5_context context, krb5_crypto crypto, size_t data_len) { struct _krb5_encryption_type *et = crypto->et; size_t padsize = et->padsize; size_t checksumsize = CHECKSUMSIZE(et->checksum); size_t res; res = et->confoundersize + checksumsize + data_len; res = (res + padsize - 1) / padsize * padsize; return res; } static size_t wrapped_length_dervied (krb5_context context, krb5_crypto crypto, size_t data_len) { struct _krb5_encryption_type *et = crypto->et; size_t padsize = et->padsize; size_t res; res = et->confoundersize + data_len; res = (res + padsize - 1) / padsize * padsize; if (et->keyed_checksum) res += et->keyed_checksum->checksumsize; else res += et->checksum->checksumsize; return res; } /* * Return the size of an encrypted packet of length `data_len' */ KRB5_LIB_FUNCTION size_t KRB5_LIB_CALL krb5_get_wrapped_length (krb5_context context, krb5_crypto crypto, size_t data_len) { if (derived_crypto (context, crypto)) return wrapped_length_dervied (context, crypto, data_len); else return wrapped_length (context, crypto, data_len); } /* * Return the size of an encrypted packet of length `data_len' */ static size_t crypto_overhead (krb5_context context, krb5_crypto crypto) { struct _krb5_encryption_type *et = crypto->et; size_t res; res = CHECKSUMSIZE(et->checksum); res += et->confoundersize; if (et->padsize > 1) res += et->padsize; return res; } static size_t crypto_overhead_dervied (krb5_context context, krb5_crypto crypto) { struct _krb5_encryption_type *et = crypto->et; size_t res; if (et->keyed_checksum) res = CHECKSUMSIZE(et->keyed_checksum); else res = CHECKSUMSIZE(et->checksum); res += et->confoundersize; if (et->padsize > 1) res += et->padsize; return res; } KRB5_LIB_FUNCTION size_t KRB5_LIB_CALL krb5_crypto_overhead (krb5_context context, krb5_crypto crypto) { if (derived_crypto (context, crypto)) return crypto_overhead_dervied (context, crypto); else return crypto_overhead (context, crypto); } /** * Converts the random bytestring to a protocol key according to * Kerberos crypto frame work. It may be assumed that all the bits of * the input string are equally random, even though the entropy * present in the random source may be limited. * * @param context Kerberos 5 context * @param type the enctype resulting key will be of * @param data input random data to convert to a key * @param size size of input random data, at least krb5_enctype_keysize() long * @param key key, output key, free with krb5_free_keyblock_contents() * * @return Return an error code or 0. * * @ingroup krb5_crypto */ KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL krb5_random_to_key(krb5_context context, krb5_enctype type, const void *data, size_t size, krb5_keyblock *key) { krb5_error_code ret; struct _krb5_encryption_type *et = _krb5_find_enctype(type); if(et == NULL) { krb5_set_error_message(context, KRB5_PROG_ETYPE_NOSUPP, N_("encryption type %d not supported", ""), type); return KRB5_PROG_ETYPE_NOSUPP; } if ((et->keytype->bits + 7) / 8 > size) { krb5_set_error_message(context, KRB5_PROG_ETYPE_NOSUPP, N_("encryption key %s needs %d bytes " "of random to make an encryption key " "out of it", ""), et->name, (int)et->keytype->size); return KRB5_PROG_ETYPE_NOSUPP; } ret = krb5_data_alloc(&key->keyvalue, et->keytype->size); if(ret) return ret; key->keytype = type; if (et->keytype->random_to_key) (*et->keytype->random_to_key)(context, key, data, size); else memcpy(key->keyvalue.data, data, et->keytype->size); return 0; } KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL krb5_crypto_prf_length(krb5_context context, krb5_enctype type, size_t *length) { struct _krb5_encryption_type *et = _krb5_find_enctype(type); if(et == NULL || et->prf_length == 0) { krb5_set_error_message(context, KRB5_PROG_ETYPE_NOSUPP, N_("encryption type %d not supported", ""), type); return KRB5_PROG_ETYPE_NOSUPP; } *length = et->prf_length; return 0; } KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL krb5_crypto_prf(krb5_context context, const krb5_crypto crypto, const krb5_data *input, krb5_data *output) { struct _krb5_encryption_type *et = crypto->et; krb5_data_zero(output); if(et->prf == NULL) { krb5_set_error_message(context, KRB5_PROG_ETYPE_NOSUPP, "kerberos prf for %s not supported", et->name); return KRB5_PROG_ETYPE_NOSUPP; } return (*et->prf)(context, crypto, input, output); } static krb5_error_code krb5_crypto_prfplus(krb5_context context, const krb5_crypto crypto, const krb5_data *input, size_t length, krb5_data *output) { krb5_error_code ret; krb5_data input2; unsigned char i = 1; unsigned char *p; krb5_data_zero(&input2); krb5_data_zero(output); krb5_clear_error_message(context); ret = krb5_data_alloc(output, length); if (ret) goto out; ret = krb5_data_alloc(&input2, input->length + 1); if (ret) goto out; krb5_clear_error_message(context); memcpy(((unsigned char *)input2.data) + 1, input->data, input->length); p = output->data; while (length) { krb5_data block; ((unsigned char *)input2.data)[0] = i++; ret = krb5_crypto_prf(context, crypto, &input2, &block); if (ret) goto out; if (block.length < length) { memcpy(p, block.data, block.length); length -= block.length; } else { memcpy(p, block.data, length); length = 0; } p += block.length; krb5_data_free(&block); } out: krb5_data_free(&input2); if (ret) krb5_data_free(output); return 0; } /** * The FX-CF2 key derivation function, used in FAST and preauth framework. * * @param context Kerberos 5 context * @param crypto1 first key to combine * @param crypto2 second key to combine * @param pepper1 factor to combine with first key to garante uniqueness * @param pepper2 factor to combine with second key to garante uniqueness * @param enctype the encryption type of the resulting key * @param res allocated key, free with krb5_free_keyblock_contents() * * @return Return an error code or 0. * * @ingroup krb5_crypto */ KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL krb5_crypto_fx_cf2(krb5_context context, const krb5_crypto crypto1, const krb5_crypto crypto2, krb5_data *pepper1, krb5_data *pepper2, krb5_enctype enctype, krb5_keyblock *res) { krb5_error_code ret; krb5_data os1, os2; size_t i, keysize; memset(res, 0, sizeof(*res)); ret = krb5_enctype_keysize(context, enctype, &keysize); if (ret) return ret; ret = krb5_data_alloc(&res->keyvalue, keysize); if (ret) goto out; ret = krb5_crypto_prfplus(context, crypto1, pepper1, keysize, &os1); if (ret) goto out; ret = krb5_crypto_prfplus(context, crypto2, pepper2, keysize, &os2); if (ret) goto out; res->keytype = enctype; { unsigned char *p1 = os1.data, *p2 = os2.data, *p3 = res->keyvalue.data; for (i = 0; i < keysize; i++) p3[i] = p1[i] ^ p2[i]; } out: if (ret) krb5_data_free(&res->keyvalue); krb5_data_free(&os1); krb5_data_free(&os2); return ret; } #ifndef HEIMDAL_SMALLER /** * Deprecated: keytypes doesn't exists, they are really enctypes. * * @ingroup krb5_deprecated */ KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL krb5_keytype_to_enctypes (krb5_context context, krb5_keytype keytype, unsigned *len, krb5_enctype **val) KRB5_DEPRECATED_FUNCTION("Use X instead") { int i; unsigned n = 0; krb5_enctype *ret; for (i = _krb5_num_etypes - 1; i >= 0; --i) { if (_krb5_etypes[i]->keytype->type == keytype && !(_krb5_etypes[i]->flags & F_PSEUDO) && krb5_enctype_valid(context, _krb5_etypes[i]->type) == 0) ++n; } if (n == 0) { krb5_set_error_message(context, KRB5_PROG_KEYTYPE_NOSUPP, "Keytype have no mapping"); return KRB5_PROG_KEYTYPE_NOSUPP; } ret = malloc(n * sizeof(*ret)); if (ret == NULL && n != 0) { krb5_set_error_message(context, ENOMEM, "malloc: out of memory"); return ENOMEM; } n = 0; for (i = _krb5_num_etypes - 1; i >= 0; --i) { if (_krb5_etypes[i]->keytype->type == keytype && !(_krb5_etypes[i]->flags & F_PSEUDO) && krb5_enctype_valid(context, _krb5_etypes[i]->type) == 0) ret[n++] = _krb5_etypes[i]->type; } *len = n; *val = ret; return 0; } /** * Deprecated: keytypes doesn't exists, they are really enctypes. * * @ingroup krb5_deprecated */ /* if two enctypes have compatible keys */ KRB5_LIB_FUNCTION krb5_boolean KRB5_LIB_CALL krb5_enctypes_compatible_keys(krb5_context context, krb5_enctype etype1, krb5_enctype etype2) KRB5_DEPRECATED_FUNCTION("Use X instead") { struct _krb5_encryption_type *e1 = _krb5_find_enctype(etype1); struct _krb5_encryption_type *e2 = _krb5_find_enctype(etype2); return e1 != NULL && e2 != NULL && e1->keytype == e2->keytype; } #endif /* HEIMDAL_SMALLER */