diff options
Diffstat (limited to 'source4/heimdal/lib/hdb/keys.c')
| -rw-r--r-- | source4/heimdal/lib/hdb/keys.c | 401 |
1 files changed, 401 insertions, 0 deletions
diff --git a/source4/heimdal/lib/hdb/keys.c b/source4/heimdal/lib/hdb/keys.c new file mode 100644 index 0000000000..e649f445e0 --- /dev/null +++ b/source4/heimdal/lib/hdb/keys.c @@ -0,0 +1,401 @@ +/* + * Copyright (c) 1997 - 2001, 2003 - 2004 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 "hdb_locl.h" + +RCSID("$Id$"); + +/* + * free all the memory used by (len, keys) + */ + +void +hdb_free_keys (krb5_context context, int len, Key *keys) +{ + int i; + + for (i = 0; i < len; i++) { + free(keys[i].mkvno); + keys[i].mkvno = NULL; + if (keys[i].salt != NULL) { + free_Salt(keys[i].salt); + free(keys[i].salt); + keys[i].salt = NULL; + } + krb5_free_keyblock_contents(context, &keys[i].key); + } + free (keys); +} + +/* + * for each entry in `default_keys' try to parse it as a sequence + * of etype:salttype:salt, syntax of this if something like: + * [(des|des3|etype):](pw-salt|afs3)[:string], if etype is omitted it + * means all etypes, and if string is omitted is means the default + * string (for that principal). Additional special values: + * v5 == pw-salt, and + * v4 == des:pw-salt: + * afs or afs3 == des:afs3-salt + */ + +static const krb5_enctype des_etypes[] = { + ETYPE_DES_CBC_MD5, + ETYPE_DES_CBC_MD4, + ETYPE_DES_CBC_CRC +}; + +static const krb5_enctype all_etypes[] = { + ETYPE_AES256_CTS_HMAC_SHA1_96, + ETYPE_ARCFOUR_HMAC_MD5, + ETYPE_DES3_CBC_SHA1 +}; + +static krb5_error_code +parse_key_set(krb5_context context, const char *key, + krb5_enctype **ret_enctypes, size_t *ret_num_enctypes, + krb5_salt *salt, krb5_principal principal) +{ + const char *p; + char buf[3][256]; + int num_buf = 0; + int i, num_enctypes = 0; + krb5_enctype e; + const krb5_enctype *enctypes = NULL; + krb5_error_code ret; + + p = key; + + *ret_enctypes = NULL; + *ret_num_enctypes = 0; + + /* split p in a list of :-separated strings */ + for(num_buf = 0; num_buf < 3; num_buf++) + if(strsep_copy(&p, ":", buf[num_buf], sizeof(buf[num_buf])) == -1) + break; + + salt->saltvalue.data = NULL; + salt->saltvalue.length = 0; + + for(i = 0; i < num_buf; i++) { + if(enctypes == NULL && num_buf > 1) { + /* this might be a etype specifier */ + /* XXX there should be a string_to_etypes handling + special cases like `des' and `all' */ + if(strcmp(buf[i], "des") == 0) { + enctypes = des_etypes; + num_enctypes = sizeof(des_etypes)/sizeof(des_etypes[0]); + } else if(strcmp(buf[i], "des3") == 0) { + e = ETYPE_DES3_CBC_SHA1; + enctypes = &e; + num_enctypes = 1; + } else { + ret = krb5_string_to_enctype(context, buf[i], &e); + if (ret == 0) { + enctypes = &e; + num_enctypes = 1; + } else + return ret; + } + continue; + } + if(salt->salttype == 0) { + /* interpret string as a salt specifier, if no etype + is set, this sets default values */ + /* XXX should perhaps use string_to_salttype, but that + interface sucks */ + if(strcmp(buf[i], "pw-salt") == 0) { + if(enctypes == NULL) { + enctypes = all_etypes; + num_enctypes = sizeof(all_etypes)/sizeof(all_etypes[0]); + } + salt->salttype = KRB5_PW_SALT; + } else if(strcmp(buf[i], "afs3-salt") == 0) { + if(enctypes == NULL) { + enctypes = des_etypes; + num_enctypes = sizeof(des_etypes)/sizeof(des_etypes[0]); + } + salt->salttype = KRB5_AFS3_SALT; + } + continue; + } + + { + /* if there is a final string, use it as the string to + salt with, this is mostly useful with null salt for + v4 compat, and a cell name for afs compat */ + salt->saltvalue.data = strdup(buf[i]); + if (salt->saltvalue.data == NULL) { + krb5_set_error_message(context, ENOMEM, "malloc: out of memory"); + return ENOMEM; + } + salt->saltvalue.length = strlen(buf[i]); + } + } + + if(enctypes == NULL || salt->salttype == 0) { + krb5_set_error_message(context, EINVAL, "bad value for default_keys `%s'", key); + return EINVAL; + } + + /* if no salt was specified make up default salt */ + if(salt->saltvalue.data == NULL) { + if(salt->salttype == KRB5_PW_SALT) + ret = krb5_get_pw_salt(context, principal, salt); + else if(salt->salttype == KRB5_AFS3_SALT) { + krb5_realm *realm = krb5_princ_realm(context, principal); + salt->saltvalue.data = strdup(*realm); + if(salt->saltvalue.data == NULL) { + krb5_set_error_message(context, ENOMEM, + "out of memory while " + "parsing salt specifiers"); + return ENOMEM; + } + strlwr(salt->saltvalue.data); + salt->saltvalue.length = strlen(*realm); + } + } + + *ret_enctypes = malloc(sizeof(enctypes[0]) * num_enctypes); + if (*ret_enctypes == NULL) { + krb5_free_salt(context, *salt); + krb5_set_error_message(context, ENOMEM, "malloc: out of memory"); + return ENOMEM; + } + memcpy(*ret_enctypes, enctypes, sizeof(enctypes[0]) * num_enctypes); + *ret_num_enctypes = num_enctypes; + + return 0; +} + +static krb5_error_code +add_enctype_to_key_set(Key **key_set, size_t *nkeyset, + krb5_enctype enctype, krb5_salt *salt) +{ + krb5_error_code ret; + Key key, *tmp; + + memset(&key, 0, sizeof(key)); + + tmp = realloc(*key_set, (*nkeyset + 1) * sizeof((*key_set)[0])); + if (tmp == NULL) + return ENOMEM; + + *key_set = tmp; + + key.key.keytype = enctype; + key.key.keyvalue.length = 0; + key.key.keyvalue.data = NULL; + + if (salt) { + key.salt = malloc(sizeof(*key.salt)); + if (key.salt == NULL) { + free_Key(&key); + return ENOMEM; + } + + key.salt->type = salt->salttype; + krb5_data_zero (&key.salt->salt); + + ret = krb5_data_copy(&key.salt->salt, + salt->saltvalue.data, + salt->saltvalue.length); + if (ret) { + free_Key(&key); + return ret; + } + } else + key.salt = NULL; + + (*key_set)[*nkeyset] = key; + + *nkeyset += 1; + + return 0; +} + + +/* + * Generate the `key_set' from the [kadmin]default_keys statement. If + * `no_salt' is set, salt is not important (and will not be set) since + * it's random keys that is going to be created. + */ + +krb5_error_code +hdb_generate_key_set(krb5_context context, krb5_principal principal, + Key **ret_key_set, size_t *nkeyset, int no_salt) +{ + char **ktypes, **kp; + krb5_error_code ret; + Key *k, *key_set; + int i, j; + char *default_keytypes[] = { + "des:pw-salt", + "aes256-cts-hmac-sha1-96:pw-salt", + "des3-cbc-sha1:pw-salt", + "arcfour-hmac-md5:pw-salt", + NULL + }; + + ktypes = krb5_config_get_strings(context, NULL, "kadmin", + "default_keys", NULL); + if (ktypes == NULL) + ktypes = default_keytypes; + + if (ktypes == NULL) + abort(); + + *ret_key_set = key_set = NULL; + *nkeyset = 0; + + ret = 0; + + for(kp = ktypes; kp && *kp; kp++) { + const char *p; + krb5_salt salt; + krb5_enctype *enctypes; + size_t num_enctypes; + + p = *kp; + /* check alias */ + if(strcmp(p, "v5") == 0) + p = "pw-salt"; + else if(strcmp(p, "v4") == 0) + p = "des:pw-salt:"; + else if(strcmp(p, "afs") == 0 || strcmp(p, "afs3") == 0) + p = "des:afs3-salt"; + else if (strcmp(p, "arcfour-hmac-md5") == 0) + p = "arcfour-hmac-md5:pw-salt"; + + memset(&salt, 0, sizeof(salt)); + + ret = parse_key_set(context, p, + &enctypes, &num_enctypes, &salt, principal); + if (ret) { + krb5_warn(context, ret, "bad value for default_keys `%s'", *kp); + ret = 0; + continue; + } + + for (i = 0; i < num_enctypes; i++) { + /* find duplicates */ + for (j = 0; j < *nkeyset; j++) { + + k = &key_set[j]; + + if (k->key.keytype == enctypes[i]) { + if (no_salt) + break; + if (k->salt == NULL && salt.salttype == KRB5_PW_SALT) + break; + if (k->salt->type == salt.salttype && + k->salt->salt.length == salt.saltvalue.length && + memcmp(k->salt->salt.data, salt.saltvalue.data, + salt.saltvalue.length) == 0) + break; + } + } + /* not a duplicate, lets add it */ + if (j == *nkeyset) { + ret = add_enctype_to_key_set(&key_set, nkeyset, enctypes[i], + no_salt ? NULL : &salt); + if (ret) { + free(enctypes); + krb5_free_salt(context, salt); + goto out; + } + } + } + free(enctypes); + krb5_free_salt(context, salt); + } + + *ret_key_set = key_set; + + out: + if (ktypes != default_keytypes) + krb5_config_free_strings(ktypes); + + if (ret) { + krb5_warn(context, ret, + "failed to parse the [kadmin]default_keys values"); + + for (i = 0; i < *nkeyset; i++) + free_Key(&key_set[i]); + free(key_set); + } else if (*nkeyset == 0) { + krb5_warnx(context, + "failed to parse any of the [kadmin]default_keys values"); + ret = EINVAL; /* XXX */ + } + + return ret; +} + + +krb5_error_code +hdb_generate_key_set_password(krb5_context context, + krb5_principal principal, + const char *password, + Key **keys, size_t *num_keys) +{ + krb5_error_code ret; + int i; + + ret = hdb_generate_key_set(context, principal, + keys, num_keys, 0); + if (ret) + return ret; + + for (i = 0; i < (*num_keys); i++) { + krb5_salt salt; + + salt.salttype = (*keys)[i].salt->type; + salt.saltvalue.length = (*keys)[i].salt->salt.length; + salt.saltvalue.data = (*keys)[i].salt->salt.data; + + ret = krb5_string_to_key_salt (context, + (*keys)[i].key.keytype, + password, + salt, + &(*keys)[i].key); + + if(ret) + break; + } + + if(ret) { + hdb_free_keys (context, *num_keys, *keys); + return ret; + } + return ret; +} |