diff options
Diffstat (limited to 'crypto/kerberosIV/lib/krb/getrealm.c')
| -rw-r--r-- | crypto/kerberosIV/lib/krb/getrealm.c | 184 |
1 files changed, 184 insertions, 0 deletions
diff --git a/crypto/kerberosIV/lib/krb/getrealm.c b/crypto/kerberosIV/lib/krb/getrealm.c new file mode 100644 index 0000000000000..05dfdabb5740f --- /dev/null +++ b/crypto/kerberosIV/lib/krb/getrealm.c @@ -0,0 +1,184 @@ +/* + Copyright (C) 1989 by the Massachusetts Institute of Technology + + Export of this software from the United States of America is assumed + to require a specific license from the United States Government. + It is the responsibility of any person or organization contemplating + export to obtain such a license before exporting. + +WITHIN THAT CONSTRAINT, permission to use, copy, modify, and +distribute this software and its documentation for any purpose and +without fee is hereby granted, provided that the above copyright +notice appear in all copies and that both that copyright notice and +this permission notice appear in supporting documentation, and that +the name of M.I.T. not be used in advertising or publicity pertaining +to distribution of the software without specific, written prior +permission. M.I.T. makes no representations about the suitability of +this software for any purpose. It is provided "as is" without express +or implied warranty. + + */ + +#include "krb_locl.h" + +RCSID("$Id: getrealm.c,v 1.25 1997/05/02 14:29:14 assar Exp $"); + +#define MATCH_SUBDOMAINS 0 + +/* + * krb_realmofhost. + * Given a fully-qualified domain-style primary host name, + * return the name of the Kerberos realm for the host. + * If the hostname contains no discernable domain, or an error occurs, + * return the local realm name, as supplied by get_krbrlm(). + * If the hostname contains a domain, but no translation is found, + * the hostname's domain is converted to upper-case and returned. + * + * The format of each line of the translation file is: + * domain_name kerberos_realm + * -or- + * host_name kerberos_realm + * + * domain_name should be of the form .XXX.YYY (e.g. .LCS.MIT.EDU) + * host names should be in the usual form (e.g. FOO.BAR.BAZ) + */ + +/* To automagically find the correct realm of a host (without + * krb.realms) add a text record for your domain with the name of your + * realm, like this: + * + * krb4-realm IN TXT FOO.SE + * + * The search is recursive, so you can also add entries for specific + * hosts. To find the realm of host a.b.c, it first tries + * krb4-realm.a.b.c, then krb4-realm.b.c and so on. + */ + +static int +dns_find_realm(char *hostname, char *realm) +{ + char domain[MaxHostNameLen + sizeof("krb4-realm..")]; + char *p; + int level = 0; + struct dns_reply *r; + + p = hostname; + + while(1){ + snprintf(domain, sizeof(domain), "krb4-realm.%s.", p); + r = dns_lookup(domain, "TXT"); + if(r){ + struct resource_record *rr = r->head; + while(rr){ + if(rr->type == T_TXT){ + strncpy(realm, rr->u.txt, REALM_SZ); + realm[REALM_SZ - 1] = 0; + dns_free_data(r); + return level; + } + rr = rr->next; + } + dns_free_data(r); + } + level++; + p = strchr(p, '.'); + if(p == NULL) + break; + p++; + } + return -1; +} + + +static FILE * +open_krb_realms(void) +{ + static const char *const files[] = KRB_RLM_FILES; + FILE *res; + int i; + + const char *dir = getenv("KRBCONFDIR"); + + /* First try user specified file */ + if (dir != 0) { + char fname[MaxPathLen]; + + if(k_concat(fname, sizeof(fname), dir, "/krb.realms", NULL) == 0) + if ((res = fopen(fname, "r")) != NULL) + return res; + } + + for (i = 0; files[i] != 0; i++) + if ((res = fopen(files[i], "r")) != NULL) + return res; + + return NULL; +} + +char * +krb_realmofhost(const char *host) +{ + static char ret_realm[REALM_SZ]; + char *domain; + FILE *trans_file; + char trans_host[MaxHostNameLen]; + char trans_realm[REALM_SZ]; + char buf[1024]; + + char phost[MaxHostNameLen]; + + krb_name_to_name(host, phost, sizeof(phost)); + + domain = strchr(phost, '.'); + + /* prepare default */ + if(dns_find_realm(phost, ret_realm) < 0){ + if (domain) { + char *cp; + + strncpy(ret_realm, &domain[1], REALM_SZ); + ret_realm[REALM_SZ - 1] = 0; + /* Upper-case realm */ + for (cp = ret_realm; *cp; cp++) + *cp = toupper(*cp); + } else { + krb_get_lrealm(ret_realm, 1); + } + } + + if ((trans_file = open_krb_realms()) == NULL) + return(ret_realm); /* krb_errno = KRB_NO_TRANS */ + + while (fgets(buf, sizeof(buf), trans_file)) { + char *save = NULL; + char *tok = strtok_r(buf, " \t\r\n", &save); + if(tok == NULL) + continue; + strncpy(trans_host, tok, MaxHostNameLen); + trans_host[MaxHostNameLen - 1] = 0; + tok = strtok_r(NULL, " \t\r\n", &save); + if(tok == NULL) + continue; + strcpy(trans_realm, tok); + trans_realm[REALM_SZ - 1] = 0; + if (!strcasecmp(trans_host, phost)) { + /* exact match of hostname, so return the realm */ + strcpy(ret_realm, trans_realm); + fclose(trans_file); + return(ret_realm); + } + if ((trans_host[0] == '.') && domain) { + char *cp = domain; + do { + if(strcasecmp(trans_host, domain) == 0){ + /* domain match, save for later */ + strcpy(ret_realm, trans_realm); + break; + } + cp = strchr(cp + 1, '.'); + } while(MATCH_SUBDOMAINS && cp); + } + } + fclose(trans_file); + return ret_realm; +} |