/* $NetBSD: keytab.c,v 1.2.22.1 2023/08/11 13:39:59 martin Exp $ */ /* * Copyright (c) 1999 - 2002 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" /* keytab backend for HDB databases */ struct hdb_data { char *dbname; char *mkey; }; struct hdb_cursor { HDB *db; hdb_entry_ex hdb_entry; int first, next; int key_idx; }; /* * the format for HDB keytabs is: * HDB:[HDBFORMAT:database-specific-data[:mkey=mkey-file]] */ static krb5_error_code KRB5_CALLCONV hdb_resolve(krb5_context context, const char *name, krb5_keytab id) { struct hdb_data *d; const char *db, *mkey; d = malloc(sizeof(*d)); if(d == NULL) { krb5_set_error_message(context, ENOMEM, "malloc: out of memory"); return ENOMEM; } db = name; mkey = strstr(name, ":mkey="); if(mkey == NULL || mkey[6] == '\0') { if(*name == '\0') d->dbname = NULL; else { d->dbname = strdup(name); if(d->dbname == NULL) { free(d); krb5_set_error_message(context, ENOMEM, "malloc: out of memory"); return ENOMEM; } } d->mkey = NULL; } else { d->dbname = malloc(mkey - db + 1); if(d->dbname == NULL) { free(d); krb5_set_error_message(context, ENOMEM, "malloc: out of memory"); return ENOMEM; } memmove(d->dbname, db, mkey - db); d->dbname[mkey - db] = '\0'; d->mkey = strdup(mkey + 6); if(d->mkey == NULL) { free(d->dbname); free(d); krb5_set_error_message(context, ENOMEM, "malloc: out of memory"); return ENOMEM; } } id->data = d; return 0; } static krb5_error_code KRB5_CALLCONV hdb_close(krb5_context context, krb5_keytab id) { struct hdb_data *d = id->data; free(d->dbname); free(d->mkey); free(d); return 0; } static krb5_error_code KRB5_CALLCONV hdb_get_name(krb5_context context, krb5_keytab id, char *name, size_t namesize) { struct hdb_data *d = id->data; snprintf(name, namesize, "%s%s%s", d->dbname ? d->dbname : "", (d->dbname || d->mkey) ? ":" : "", d->mkey ? d->mkey : ""); return 0; } /* * try to figure out the database (`dbname') and master-key (`mkey') * that should be used for `principal'. */ static krb5_error_code find_db (krb5_context context, char **dbname, char **mkey, krb5_const_principal principal) { krb5_const_realm realm = krb5_principal_get_realm(context, principal); krb5_error_code ret; struct hdb_dbinfo *head, *dbinfo = NULL; *dbname = *mkey = NULL; ret = hdb_get_dbinfo(context, &head); if (ret) return ret; while ((dbinfo = hdb_dbinfo_get_next(head, dbinfo)) != NULL) { const char *p = hdb_dbinfo_get_realm(context, dbinfo); if (p && strcmp (realm, p) == 0) { p = hdb_dbinfo_get_dbname(context, dbinfo); if (p) *dbname = strdup(p); p = hdb_dbinfo_get_mkey_file(context, dbinfo); if (p) *mkey = strdup(p); break; } } hdb_free_dbinfo(context, &head); if (*dbname == NULL && (*dbname = strdup(HDB_DEFAULT_DB)) == NULL) { free(*mkey); *mkey = NULL; return krb5_enomem(context); } return 0; } /* * find the keytab entry in `id' for `principal, kvno, enctype' and return * it in `entry'. return 0 or an error code */ static krb5_error_code KRB5_CALLCONV hdb_get_entry(krb5_context context, krb5_keytab id, krb5_const_principal principal, krb5_kvno kvno, krb5_enctype enctype, krb5_keytab_entry *entry) { hdb_entry_ex ent; krb5_error_code ret; struct hdb_data *d = id->data; const char *dbname = d->dbname; const char *mkey = d->mkey; char *fdbname = NULL, *fmkey = NULL; HDB *db; size_t i; memset(&ent, 0, sizeof(ent)); if (dbname == NULL) { ret = find_db(context, &fdbname, &fmkey, principal); if (ret) return ret; dbname = fdbname; mkey = fmkey; } ret = hdb_create (context, &db, dbname); if (ret) goto out2; ret = hdb_set_master_keyfile (context, db, mkey); if (ret) { (*db->hdb_destroy)(context, db); goto out2; } ret = (*db->hdb_open)(context, db, O_RDONLY, 0); if (ret) { (*db->hdb_destroy)(context, db); goto out2; } ret = (*db->hdb_fetch_kvno)(context, db, principal, HDB_F_DECRYPT|HDB_F_KVNO_SPECIFIED| HDB_F_GET_CLIENT|HDB_F_GET_SERVER|HDB_F_GET_KRBTGT, kvno, &ent); if(ret == HDB_ERR_NOENTRY) { ret = KRB5_KT_NOTFOUND; goto out; }else if(ret) goto out; if(kvno && (krb5_kvno)ent.entry.kvno != kvno) { hdb_free_entry(context, &ent); ret = KRB5_KT_NOTFOUND; goto out; } if(enctype == 0) if(ent.entry.keys.len > 0) enctype = ent.entry.keys.val[0].key.keytype; ret = KRB5_KT_NOTFOUND; for(i = 0; i < ent.entry.keys.len; i++) { if(ent.entry.keys.val[i].key.keytype == enctype) { krb5_copy_principal(context, principal, &entry->principal); entry->vno = ent.entry.kvno; krb5_copy_keyblock_contents(context, &ent.entry.keys.val[i].key, &entry->keyblock); ret = 0; break; } } hdb_free_entry(context, &ent); out: (*db->hdb_close)(context, db); (*db->hdb_destroy)(context, db); out2: free(fdbname); free(fmkey); return ret; } /* * find the keytab entry in `id' for `principal, kvno, enctype' and return * it in `entry'. return 0 or an error code */ static krb5_error_code KRB5_CALLCONV hdb_start_seq_get(krb5_context context, krb5_keytab id, krb5_kt_cursor *cursor) { krb5_error_code ret; struct hdb_cursor *c; struct hdb_data *d = id->data; const char *dbname = d->dbname; const char *mkey = d->mkey; HDB *db; if (dbname == NULL) { /* * We don't support enumerating without being told what * backend to enumerate on */ ret = KRB5_KT_NOTFOUND; return ret; } ret = hdb_create (context, &db, dbname); if (ret) return ret; ret = hdb_set_master_keyfile (context, db, mkey); if (ret) { (*db->hdb_destroy)(context, db); return ret; } ret = (*db->hdb_open)(context, db, O_RDONLY, 0); if (ret) { (*db->hdb_destroy)(context, db); return ret; } cursor->data = c = malloc (sizeof(*c)); if(c == NULL){ (*db->hdb_close)(context, db); (*db->hdb_destroy)(context, db); krb5_set_error_message(context, ENOMEM, "malloc: out of memory"); return ENOMEM; } c->db = db; c->first = TRUE; c->next = TRUE; c->key_idx = 0; cursor->data = c; return ret; } static int KRB5_CALLCONV hdb_next_entry(krb5_context context, krb5_keytab id, krb5_keytab_entry *entry, krb5_kt_cursor *cursor) { struct hdb_cursor *c = cursor->data; krb5_error_code ret; memset(entry, 0, sizeof(*entry)); if (c->first) { c->first = FALSE; ret = (c->db->hdb_firstkey)(context, c->db, HDB_F_DECRYPT| HDB_F_GET_CLIENT|HDB_F_GET_SERVER|HDB_F_GET_KRBTGT, &c->hdb_entry); if (ret == HDB_ERR_NOENTRY) return KRB5_KT_END; else if (ret) return ret; if (c->hdb_entry.entry.keys.len == 0) hdb_free_entry(context, &c->hdb_entry); else c->next = FALSE; } while (c->next) { ret = (c->db->hdb_nextkey)(context, c->db, HDB_F_DECRYPT| HDB_F_GET_CLIENT|HDB_F_GET_SERVER|HDB_F_GET_KRBTGT, &c->hdb_entry); if (ret == HDB_ERR_NOENTRY) return KRB5_KT_END; else if (ret) return ret; /* If no keys on this entry, try again */ if (c->hdb_entry.entry.keys.len == 0) hdb_free_entry(context, &c->hdb_entry); else c->next = FALSE; } /* * Return next enc type (keytabs are one slot per key, while * hdb is one record per principal. */ ret = krb5_copy_principal(context, c->hdb_entry.entry.principal, &entry->principal); if (ret) return ret; entry->vno = c->hdb_entry.entry.kvno; ret = krb5_copy_keyblock_contents(context, &c->hdb_entry.entry.keys.val[c->key_idx].key, &entry->keyblock); if (ret) { krb5_free_principal(context, entry->principal); memset(entry, 0, sizeof(*entry)); return ret; } c->key_idx++; /* * Once we get to the end of the list, signal that we want the * next entry */ if ((size_t)c->key_idx == c->hdb_entry.entry.keys.len) { hdb_free_entry(context, &c->hdb_entry); c->next = TRUE; c->key_idx = 0; } return 0; } static int KRB5_CALLCONV hdb_end_seq_get(krb5_context context, krb5_keytab id, krb5_kt_cursor *cursor) { struct hdb_cursor *c = cursor->data; if (!c->next) hdb_free_entry(context, &c->hdb_entry); (c->db->hdb_close)(context, c->db); (c->db->hdb_destroy)(context, c->db); free(c); return 0; } krb5_kt_ops hdb_kt_ops = { "HDB", hdb_resolve, hdb_get_name, hdb_close, NULL, /* destroy */ hdb_get_entry, hdb_start_seq_get, hdb_next_entry, hdb_end_seq_get, NULL, /* add */ NULL, /* remove */ NULL, 0 }; krb5_kt_ops hdb_get_kt_ops = { "HDBGET", hdb_resolve, hdb_get_name, hdb_close, NULL, hdb_get_entry, NULL, NULL, NULL, NULL, NULL, NULL, 0 };