/*
- * Dug Song <dugsong@UMICH.EDU>
- * Kerberos v4 authentication and ticket-passing routines.
+ * Copyright (c) 1999 Dug Song. 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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 "includes.h"
+RCSID("$OpenBSD: auth-krb4.c,v 1.23 2001/01/22 08:15:00 markus Exp $");
+
+#include "ssh.h"
+#include "ssh1.h"
#include "packet.h"
#include "xmalloc.h"
-#include "ssh.h"
+#include "log.h"
+#include "servconf.h"
+#include "auth.h"
+
+#ifdef AFS
+#include "radix.h"
+#endif
#ifdef KRB4
char *ticket = NULL;
+extern ServerOptions options;
+
+/*
+ * try krb4 authentication,
+ * return 1 on success, 0 on failure, -1 if krb4 is not available
+ */
+
+int
+auth_krb4_password(struct passwd * pw, const char *password)
+{
+ AUTH_DAT adata;
+ KTEXT_ST tkt;
+ struct hostent *hp;
+ u_long faddr;
+ char localhost[MAXHOSTNAMELEN];
+ char phost[INST_SZ];
+ char realm[REALM_SZ];
+ int r;
+
+ /*
+ * Try Kerberos password authentication only for non-root
+ * users and only if Kerberos is installed.
+ */
+ if (pw->pw_uid != 0 && krb_get_lrealm(realm, 1) == KSUCCESS) {
+
+ /* Set up our ticket file. */
+ if (!krb4_init(pw->pw_uid)) {
+ log("Couldn't initialize Kerberos ticket file for %s!",
+ pw->pw_name);
+ goto kerberos_auth_failure;
+ }
+ /* Try to get TGT using our password. */
+ r = krb_get_pw_in_tkt((char *) pw->pw_name, "",
+ realm, "krbtgt", realm,
+ DEFAULT_TKT_LIFE, (char *) password);
+ if (r != INTK_OK) {
+ packet_send_debug("Kerberos V4 password "
+ "authentication for %s failed: %s",
+ pw->pw_name, krb_err_txt[r]);
+ goto kerberos_auth_failure;
+ }
+ /* Successful authentication. */
+ chown(tkt_string(), pw->pw_uid, pw->pw_gid);
+
+ /*
+ * Now that we have a TGT, try to get a local
+ * "rcmd" ticket to ensure that we are not talking
+ * to a bogus Kerberos server.
+ */
+ (void) gethostname(localhost, sizeof(localhost));
+ (void) strlcpy(phost, (char *) krb_get_phost(localhost),
+ INST_SZ);
+ r = krb_mk_req(&tkt, KRB4_SERVICE_NAME, phost, realm, 33);
+
+ if (r == KSUCCESS) {
+ if (!(hp = gethostbyname(localhost))) {
+ log("Couldn't get local host address!");
+ goto kerberos_auth_failure;
+ }
+ memmove((void *) &faddr, (void *) hp->h_addr,
+ sizeof(faddr));
+
+ /* Verify our "rcmd" ticket. */
+ r = krb_rd_req(&tkt, KRB4_SERVICE_NAME, phost,
+ faddr, &adata, "");
+ if (r == RD_AP_UNDEC) {
+ /*
+ * Probably didn't have a srvtab on
+ * localhost. Disallow login.
+ */
+ log("Kerberos V4 TGT for %s unverifiable, "
+ "no srvtab installed? krb_rd_req: %s",
+ pw->pw_name, krb_err_txt[r]);
+ goto kerberos_auth_failure;
+ } else if (r != KSUCCESS) {
+ log("Kerberos V4 %s ticket unverifiable: %s",
+ KRB4_SERVICE_NAME, krb_err_txt[r]);
+ goto kerberos_auth_failure;
+ }
+ } else if (r == KDC_PR_UNKNOWN) {
+ /*
+ * Disallow login if no rcmd service exists, and
+ * log the error.
+ */
+ log("Kerberos V4 TGT for %s unverifiable: %s; %s.%s "
+ "not registered, or srvtab is wrong?", pw->pw_name,
+ krb_err_txt[r], KRB4_SERVICE_NAME, phost);
+ goto kerberos_auth_failure;
+ } else {
+ /*
+ * TGT is bad, forget it. Possibly spoofed!
+ */
+ packet_send_debug("WARNING: Kerberos V4 TGT "
+ "possibly spoofed for %s: %s",
+ pw->pw_name, krb_err_txt[r]);
+ goto kerberos_auth_failure;
+ }
+
+ /* Authentication succeeded. */
+ return 1;
+
+kerberos_auth_failure:
+ krb4_cleanup_proc(NULL);
+
+ if (!options.kerberos_or_local_passwd)
+ return 0;
+ } else {
+ /* Logging in as root or no local Kerberos realm. */
+ packet_send_debug("Unable to authenticate to Kerberos.");
+ }
+ /* Fall back to ordinary passwd authentication. */
+ return -1;
+}
+
void
krb4_cleanup_proc(void *ignore)
{
}
}
-int
+int
krb4_init(uid_t uid)
{
static int cleanup_registered = 0;
- char *tkt_root = TKT_ROOT;
+ const char *tkt_root = TKT_ROOT;
struct stat st;
int fd;
if (lstat("/ticket", &st) != -1)
tkt_root = "/ticket/";
#endif /* AFS */
- snprintf(ticket, MAXPATHLEN, "%s%d_%d", tkt_root, uid, getpid());
+ snprintf(ticket, MAXPATHLEN, "%s%u_%d", tkt_root, uid, getpid());
(void) krb_set_tkt_string(ticket);
}
/* Register ticket cleanup in case of fatal error. */
return 0;
}
-int
+int
auth_krb4(const char *server_user, KTEXT auth, char **client)
{
AUTH_DAT adat = {0};
KTEXT_ST reply;
char instance[INST_SZ];
int r, s;
+ socklen_t slen;
u_int cksum;
Key_schedule schedule;
struct sockaddr_in local, foreign;
s = packet_get_connection_in();
- r = sizeof(local);
+ slen = sizeof(local);
memset(&local, 0, sizeof(local));
- if (getsockname(s, (struct sockaddr *) & local, &r) < 0)
+ if (getsockname(s, (struct sockaddr *) & local, &slen) < 0)
debug("getsockname failed: %.100s", strerror(errno));
- r = sizeof(foreign);
+ slen = sizeof(foreign);
memset(&foreign, 0, sizeof(foreign));
- if (getpeername(s, (struct sockaddr *) & foreign, &r) < 0) {
+ if (getpeername(s, (struct sockaddr *) & foreign, &slen) < 0) {
debug("getpeername failed: %.100s", strerror(errno));
fatal_cleanup();
}
#endif /* KRB4 */
#ifdef AFS
-int
+int
auth_kerberos_tgt(struct passwd *pw, const char *string)
{
CREDENTIALS creds;
+ if (pw == NULL)
+ goto auth_kerberos_tgt_failure;
if (!radix_to_creds(string, &creds)) {
log("Protocol error decoding Kerberos V4 tgt");
packet_send_debug("Protocol error decoding Kerberos V4 tgt");
return 0;
}
-int
+int
auth_afs_token(struct passwd *pw, const char *token_string)
{
CREDENTIALS creds;
- uid_t uid = pw->pw_uid;
+ uid_t uid;
+ if (pw == NULL) {
+ /* XXX fake protocol error */
+ packet_send_debug("Protocol error decoding AFS token");
+ packet_start(SSH_SMSG_FAILURE);
+ packet_send();
+ packet_write_wait();
+ return 0;
+ }
if (!radix_to_creds(token_string, &creds)) {
log("Protocol error decoding AFS token");
packet_send_debug("Protocol error decoding AFS token");
if (strncmp(creds.pname, "AFS ID ", 7) == 0)
uid = atoi(creds.pname + 7);
+ else
+ uid = pw->pw_uid;
if (kafs_settoken(creds.realm, uid, &creds)) {
log("AFS token (%s@%s) rejected for %s", creds.pname, creds.realm,
andersk / openssh.git / blobdiff