/* * Copyright (c) 1999 - 2001 Kungliga Tekniska H�gskolan * (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" RCSID("$Id: expand_hostname.c,v 1.14 2006/11/04 03:34:57 lha Exp $"); static krb5_error_code copy_hostname(krb5_context context, const char *orig_hostname, char **new_hostname) { *new_hostname = strdup (orig_hostname); if (*new_hostname == NULL) { krb5_set_error_string(context, "malloc: out of memory"); return ENOMEM; } strlwr (*new_hostname); return 0; } /* * Try to make `orig_hostname' into a more canonical one in the newly * allocated space returned in `new_hostname'. */ krb5_error_code KRB5_LIB_FUNCTION krb5_expand_hostname (krb5_context context, const char *orig_hostname, char **new_hostname) { struct addrinfo *ai, *a, hints; int error; if (!context->dns_canonicalize_hostname) return copy_hostname (context, orig_hostname, new_hostname); memset (&hints, 0, sizeof(hints)); hints.ai_flags = AI_CANONNAME; error = getaddrinfo (orig_hostname, NULL, &hints, &ai); if (error) return copy_hostname (context, orig_hostname, new_hostname); for (a = ai; a != NULL; a = a->ai_next) { if (a->ai_canonname != NULL) { *new_hostname = strdup (a->ai_canonname); freeaddrinfo (ai); if (*new_hostname == NULL) { krb5_set_error_string(context, "malloc: out of memory"); return ENOMEM; } else { return 0; } } } freeaddrinfo (ai); return copy_hostname (context, orig_hostname, new_hostname); } /* * handle the case of the hostname being unresolvable and thus identical */ static krb5_error_code vanilla_hostname (krb5_context context, const char *orig_hostname, char **new_hostname, char ***realms) { krb5_error_code ret; ret = copy_hostname (context, orig_hostname, new_hostname); if (ret) return ret; strlwr (*new_hostname); ret = krb5_get_host_realm (context, *new_hostname, realms); if (ret) { free (*new_hostname); return ret; } return 0; } /* * expand `hostname' to a name we believe to be a hostname in newly * allocated space in `host' and return realms in `realms'. */ krb5_error_code KRB5_LIB_FUNCTION krb5_expand_hostname_realms (krb5_context context, const char *orig_hostname, char **new_hostname, char ***realms) { struct addrinfo *ai, *a, hints; int error; krb5_error_code ret = 0; if (!context->dns_canonicalize_hostname) return vanilla_hostname (context, orig_hostname, new_hostname, realms); memset (&hints, 0, sizeof(hints)); hints.ai_flags = AI_CANONNAME; error = getaddrinfo (orig_hostname, NULL, &hints, &ai); if (error) return vanilla_hostname (context, orig_hostname, new_hostname, realms); for (a = ai; a != NULL; a = a->ai_next) { if (a->ai_canonname != NULL) { ret = copy_hostname (context, a->ai_canonname, new_hostname); if (ret) { freeaddrinfo (ai); return ret; } strlwr (*new_hostname); ret = krb5_get_host_realm (context, *new_hostname, realms); if (ret == 0) { freeaddrinfo (ai); return 0; } free (*new_hostname); } } freeaddrinfo(ai); return vanilla_hostname (context, orig_hostname, new_hostname, realms); }