diff options
Diffstat (limited to 'crypto/heimdal/lib/hdb/mkey.c')
| -rw-r--r-- | crypto/heimdal/lib/hdb/mkey.c | 211 |
1 files changed, 190 insertions, 21 deletions
diff --git a/crypto/heimdal/lib/hdb/mkey.c b/crypto/heimdal/lib/hdb/mkey.c index 9eb98fca32c0..78a9e51a132c 100644 --- a/crypto/heimdal/lib/hdb/mkey.c +++ b/crypto/heimdal/lib/hdb/mkey.c @@ -32,6 +32,7 @@ */ #include "hdb_locl.h" +#include <assert.h> #ifndef O_BINARY #define O_BINARY 0 #endif @@ -40,6 +41,7 @@ struct hdb_master_key_data { krb5_keytab_entry keytab; krb5_crypto crypto; struct hdb_master_key_data *next; + unsigned int key_usage; }; void @@ -68,6 +70,7 @@ hdb_process_master_key(krb5_context context, krb5_set_error_message(context, ENOMEM, "malloc: out of memory"); return ENOMEM; } + (*mkey)->key_usage = HDB_KU_MKEY; (*mkey)->keytab.vno = kvno; ret = krb5_parse_name(context, "K/M", &(*mkey)->keytab.principal); if(ret) @@ -362,6 +365,15 @@ hdb_write_master_key(krb5_context context, const char *filename, return ret; } +krb5_error_code +_hdb_set_master_key_usage(krb5_context context, HDB *db, unsigned int key_usage) +{ + if (db->hdb_master_key_set == 0) + return HDB_ERR_NO_MKEY; + db->hdb_master_key->key_usage = key_usage; + return 0; +} + hdb_master_key _hdb_find_master_key(uint32_t *mkvno, hdb_master_key mkey) { @@ -403,15 +415,20 @@ _hdb_mkey_encrypt(krb5_context context, hdb_master_key key, ptr, size, res); } -krb5_error_code -hdb_unseal_key_mkey(krb5_context context, Key *k, hdb_master_key mkey) +/* + * Unseal and optionally reseal the key in the MIT KDC master key. + * If mit_key != NULL, the key is sealed using this key. + */ +static krb5_error_code +_hdb_reseal_key_mkey(krb5_context context, Key *k, hdb_master_key mkey, + hdb_master_key mit_key) { krb5_error_code ret; - krb5_data res; + krb5_data mitres, res; size_t keysize; - hdb_master_key key; + hdb_master_key key, mitkey; if(k->mkvno == NULL) return 0; @@ -428,9 +445,9 @@ hdb_unseal_key_mkey(krb5_context context, Key *k, hdb_master_key mkey) if(ret == KRB5KRB_AP_ERR_BAD_INTEGRITY) { /* try to decrypt with MIT key usage */ ret = _hdb_mkey_decrypt(context, key, 0, - k->key.keyvalue.data, - k->key.keyvalue.length, - &res); + k->key.keyvalue.data, + k->key.keyvalue.length, + &res); } if (ret) return ret; @@ -446,25 +463,81 @@ hdb_unseal_key_mkey(krb5_context context, Key *k, hdb_master_key mkey) return KRB5_BAD_KEYSIZE; } - memset(k->key.keyvalue.data, 0, k->key.keyvalue.length); - free(k->key.keyvalue.data); - k->key.keyvalue = res; - k->key.keyvalue.length = keysize; - free(k->mkvno); - k->mkvno = NULL; + /* For mit_key != NULL, re-encrypt the key using the mitkey. */ + if (mit_key != NULL) { + mitkey = _hdb_find_master_key(NULL, mit_key); + if (mitkey == NULL) { + krb5_data_free(&res); + return HDB_ERR_NO_MKEY; + } + + ret = _hdb_mkey_encrypt(context, mitkey, 0, + res.data, + keysize, + &mitres); + krb5_data_free(&res); + if (ret) + return ret; + } + + krb5_data_free(&k->key.keyvalue); + if (mit_key == NULL) { + k->key.keyvalue = res; + k->key.keyvalue.length = keysize; + free(k->mkvno); + k->mkvno = NULL; + } else { + k->key.keyvalue = mitres; + *k->mkvno = mitkey->keytab.vno; + } return 0; } krb5_error_code -hdb_unseal_keys_mkey(krb5_context context, hdb_entry *ent, hdb_master_key mkey) +hdb_unseal_key_mkey(krb5_context context, Key *k, hdb_master_key mkey) +{ + + krb5_error_code ret; + + ret = _hdb_reseal_key_mkey(context, k, mkey, NULL); + return ret; +} + +static krb5_error_code +_hdb_unseal_keys_mkey(krb5_context context, hdb_entry *ent, hdb_master_key mkey, + hdb_master_key mitkey) { + krb5_error_code ret; size_t i; + int got_one = 0; for(i = 0; i < ent->keys.len; i++){ - krb5_error_code ret; + if (mitkey == NULL || mit_strong_etype(ent->keys.val[i].key.keytype)) { + ret = _hdb_reseal_key_mkey(context, &ent->keys.val[i], mkey, + mitkey); + if (ret) + return ret; + got_one = 1; + } + } - ret = hdb_unseal_key_mkey(context, &ent->keys.val[i], mkey); + /* + * If none of the keys were string enough, create a strong key, + * but one that is not encrypted in the MIT master key. As such, + * it will require a "change_password" once in the MIT KDC to + * make it work. + */ + if (got_one == 0 && mitkey != NULL && ent->keys.len > 0) { + krb5_keyblock key; + krb5_salt salt; + + krb5_free_keyblock_contents(context, &ent->keys.val[0].key); + salt.salttype = KRB5_PW_SALT; + salt.saltvalue.data = NULL; + salt.saltvalue.length = 0; + ret = krb5_string_to_key_salt(context, ETYPE_AES256_CTS_HMAC_SHA1_96, + "XXXX", salt, &ent->keys.val[0].key); if (ret) return ret; } @@ -472,19 +545,114 @@ hdb_unseal_keys_mkey(krb5_context context, hdb_entry *ent, hdb_master_key mkey) } krb5_error_code +hdb_unseal_keys_mkey(krb5_context context, hdb_entry *ent, hdb_master_key mkey) +{ + krb5_error_code ret; + + ret = _hdb_unseal_keys_mkey(context, ent, mkey, NULL); + return ret; +} + +krb5_error_code hdb_unseal_keys(krb5_context context, HDB *db, hdb_entry *ent) { if (db->hdb_master_key_set == 0) return 0; - return hdb_unseal_keys_mkey(context, ent, db->hdb_master_key); + if (db->hdb_mit_key_set != 0) + return _hdb_unseal_keys_mkey(context, ent, db->hdb_master_key, + db->hdb_mit_key); + else + return _hdb_unseal_keys_mkey(context, ent, db->hdb_master_key, + NULL); +} + +#ifdef notnow +krb5_error_code +hdb_unseal_keys_kvno(krb5_context context, HDB *db, krb5_kvno kvno, + hdb_entry *ent) +{ + krb5_error_code ret = KRB5KRB_AP_ERR_NOKEY; /* XXX need a better code? */ + HDB_extension *tmp; + HDB_Ext_KeySet *hist_keys; + hdb_keyset *tmp_keys; + Key *tmp_val; + unsigned int tmp_len; + krb5_kvno tmp_kvno; + int i, k; + + assert(kvno == 0 || kvno < ent->kvno); + + tmp = hdb_find_extension(ent, choice_HDB_extension_data_hist_keys); + if (tmp == NULL) + return ret; + + tmp_len = ent->keys.len; + tmp_val = ent->keys.val; + tmp_kvno = ent->kvno; + + hist_keys = &tmp->data.u.hist_keys; + + for (i = hist_keys->len - 1; i >= 0; i++) { + if (kvno != 0 && hist_keys->val[i].kvno != kvno) + continue; + for (k = 0; k < hist_keys->val[i].keys.len; k++) { + ret = _hdb_reseal_key_mkey(context, + &hist_keys->val[i].keys.val[k], + db->hdb_master_key, NULL); + if (ret) + return (ret); + } + + if (kvno == 0) + continue; + + /* + * NOTE: What follows is a bit of an ugly hack. + * + * This is the keyset we're being asked for, so we add the + * current keyset to the history, leave the one we were asked + * for in the history, and pretend the one we were asked for is + * also the current keyset. + * + * This is a bit of a defensive hack in case an entry fetched + * this way ever gets modified then stored: if the keyset is not + * changed we can detect this and put things back, else we won't + * drop any keysets from history by accident. + * + * Note too that we only ever get called with a non-zero kvno + * either in the KDC or in cases where we aren't changing the + * HDB entry anyways, which is why this is just a defensive + * hack. We also don't fetch specific kvnos in the dump case, + * so there's no danger that we'll dump this entry and load it + * again, repeatedly causing the history to grow boundelessly. + */ + tmp_keys = realloc(hist_keys->val, + sizeof (*hist_keys->val) * (hist_keys->len + 1)); + if (tmp_keys == NULL) + return ENOMEM; + + memmove(&tmp_keys[1], tmp_keys, + sizeof (*hist_keys->val) * hist_keys->len++); + tmp_keys[0].keys.len = ent->keys.len; + tmp_keys[0].keys.val = ent->keys.val; + tmp_keys[0].kvno = ent->kvno; + tmp_keys[0].replace_time = time(NULL); + i++; + ent->keys.len = hist_keys->val[i].keys.len; + ent->keys.val = hist_keys->val[i].keys.val; + ent->kvno = kvno; + } + + return (ret); } +#endif krb5_error_code hdb_unseal_key(krb5_context context, HDB *db, Key *k) { if (db->hdb_master_key_set == 0) return 0; - return hdb_unseal_key_mkey(context, k, db->hdb_master_key); + return _hdb_reseal_key_mkey(context, k, db->hdb_master_key, NULL); } krb5_error_code @@ -556,9 +724,9 @@ hdb_seal_key(krb5_context context, HDB *db, Key *k) } krb5_error_code -hdb_set_master_key (krb5_context context, - HDB *db, - krb5_keyblock *key) +hdb_set_master_key(krb5_context context, + HDB *db, + krb5_keyblock *key) { krb5_error_code ret; hdb_master_key mkey; @@ -571,6 +739,7 @@ hdb_set_master_key (krb5_context context, des_set_random_generator_seed(key.keyvalue.data); #endif db->hdb_master_key_set = 1; + db->hdb_master_key->key_usage = HDB_KU_MKEY; return 0; } |