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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-10 19:49:46 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-10 19:49:46 +0000
commit0b6b94e6b6152f15cf4c2247c5974f539aae28cd (patch)
treea7698198a1f527ede17a929af46e456e03d50600 /auth-krb5.c
parentInitial commit. (diff)
downloadopenssh-0b6b94e6b6152f15cf4c2247c5974f539aae28cd.tar.xz
openssh-0b6b94e6b6152f15cf4c2247c5974f539aae28cd.zip
Adding upstream version 1:9.6p1.upstream/1%9.6p1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'auth-krb5.c')
-rw-r--r--auth-krb5.c273
1 files changed, 273 insertions, 0 deletions
diff --git a/auth-krb5.c b/auth-krb5.c
new file mode 100644
index 0000000..c99e4e4
--- /dev/null
+++ b/auth-krb5.c
@@ -0,0 +1,273 @@
+/* $OpenBSD: auth-krb5.c,v 1.24 2021/04/03 06:18:40 djm Exp $ */
+/*
+ * Kerberos v5 authentication and ticket-passing routines.
+ *
+ * From: FreeBSD: src/crypto/openssh/auth-krb5.c,v 1.6 2001/02/13 16:58:04 assar
+ */
+/*
+ * Copyright (c) 2002 Daniel Kouril. 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"
+
+#include <sys/types.h>
+#include <pwd.h>
+#include <stdarg.h>
+
+#include "xmalloc.h"
+#include "ssh.h"
+#include "packet.h"
+#include "log.h"
+#include "sshbuf.h"
+#include "sshkey.h"
+#include "misc.h"
+#include "servconf.h"
+#include "uidswap.h"
+#include "hostfile.h"
+#include "auth.h"
+
+#ifdef KRB5
+#include <errno.h>
+#include <unistd.h>
+#include <string.h>
+#include <krb5.h>
+
+extern ServerOptions options;
+
+static int
+krb5_init(void *context)
+{
+ Authctxt *authctxt = (Authctxt *)context;
+ krb5_error_code problem;
+
+ if (authctxt->krb5_ctx == NULL) {
+ problem = krb5_init_context(&authctxt->krb5_ctx);
+ if (problem)
+ return (problem);
+ }
+ return (0);
+}
+
+int
+auth_krb5_password(Authctxt *authctxt, const char *password)
+{
+#ifndef HEIMDAL
+ krb5_creds creds;
+ krb5_principal server;
+#endif
+ krb5_error_code problem;
+ krb5_ccache ccache = NULL;
+ int len;
+ char *client, *platform_client;
+ const char *errmsg;
+
+ /* get platform-specific kerberos client principal name (if it exists) */
+ platform_client = platform_krb5_get_principal_name(authctxt->pw->pw_name);
+ client = platform_client ? platform_client : authctxt->pw->pw_name;
+
+ temporarily_use_uid(authctxt->pw);
+
+ problem = krb5_init(authctxt);
+ if (problem)
+ goto out;
+
+ problem = krb5_parse_name(authctxt->krb5_ctx, client,
+ &authctxt->krb5_user);
+ if (problem)
+ goto out;
+
+#ifdef HEIMDAL
+# ifdef HAVE_KRB5_CC_NEW_UNIQUE
+ problem = krb5_cc_new_unique(authctxt->krb5_ctx,
+ krb5_mcc_ops.prefix, NULL, &ccache);
+# else
+ problem = krb5_cc_gen_new(authctxt->krb5_ctx, &krb5_mcc_ops, &ccache);
+# endif
+ if (problem)
+ goto out;
+
+ problem = krb5_cc_initialize(authctxt->krb5_ctx, ccache,
+ authctxt->krb5_user);
+ if (problem)
+ goto out;
+
+ restore_uid();
+
+ problem = krb5_verify_user(authctxt->krb5_ctx, authctxt->krb5_user,
+ ccache, password, 1, NULL);
+
+ temporarily_use_uid(authctxt->pw);
+
+ if (problem)
+ goto out;
+
+# ifdef HAVE_KRB5_CC_NEW_UNIQUE
+ problem = krb5_cc_new_unique(authctxt->krb5_ctx,
+ krb5_fcc_ops.prefix, NULL, &authctxt->krb5_fwd_ccache);
+# else
+ problem = krb5_cc_gen_new(authctxt->krb5_ctx, &krb5_fcc_ops,
+ &authctxt->krb5_fwd_ccache);
+# endif
+ if (problem)
+ goto out;
+
+ problem = krb5_cc_copy_cache(authctxt->krb5_ctx, ccache,
+ authctxt->krb5_fwd_ccache);
+ krb5_cc_destroy(authctxt->krb5_ctx, ccache);
+ ccache = NULL;
+ if (problem)
+ goto out;
+
+#else
+ problem = krb5_get_init_creds_password(authctxt->krb5_ctx, &creds,
+ authctxt->krb5_user, (char *)password, NULL, NULL, 0, NULL, NULL);
+ if (problem)
+ goto out;
+
+ problem = krb5_sname_to_principal(authctxt->krb5_ctx, NULL, NULL,
+ KRB5_NT_SRV_HST, &server);
+ if (problem)
+ goto out;
+
+ restore_uid();
+ problem = krb5_verify_init_creds(authctxt->krb5_ctx, &creds, server,
+ NULL, NULL, NULL);
+ krb5_free_principal(authctxt->krb5_ctx, server);
+ temporarily_use_uid(authctxt->pw);
+ if (problem)
+ goto out;
+
+ if (!krb5_kuserok(authctxt->krb5_ctx, authctxt->krb5_user,
+ authctxt->pw->pw_name)) {
+ problem = -1;
+ goto out;
+ }
+
+ problem = ssh_krb5_cc_gen(authctxt->krb5_ctx,
+ &authctxt->krb5_fwd_ccache);
+ if (problem)
+ goto out;
+
+ problem = krb5_cc_initialize(authctxt->krb5_ctx,
+ authctxt->krb5_fwd_ccache, authctxt->krb5_user);
+ if (problem)
+ goto out;
+
+ problem = krb5_cc_store_cred(authctxt->krb5_ctx,
+ authctxt->krb5_fwd_ccache, &creds);
+ if (problem)
+ goto out;
+#endif
+
+ authctxt->krb5_ticket_file = (char *)krb5_cc_get_name(authctxt->krb5_ctx, authctxt->krb5_fwd_ccache);
+
+ len = strlen(authctxt->krb5_ticket_file) + 6;
+ authctxt->krb5_ccname = xmalloc(len);
+ snprintf(authctxt->krb5_ccname, len, "FILE:%s",
+ authctxt->krb5_ticket_file);
+
+#ifdef USE_PAM
+ if (options.use_pam)
+ do_pam_putenv("KRB5CCNAME", authctxt->krb5_ccname);
+#endif
+
+ out:
+ restore_uid();
+
+ free(platform_client);
+
+ if (problem) {
+ if (ccache)
+ krb5_cc_destroy(authctxt->krb5_ctx, ccache);
+
+ if (authctxt->krb5_ctx != NULL && problem!=-1) {
+ errmsg = krb5_get_error_message(authctxt->krb5_ctx,
+ problem);
+ debug("Kerberos password authentication failed: %s",
+ errmsg);
+ krb5_free_error_message(authctxt->krb5_ctx, errmsg);
+ } else
+ debug("Kerberos password authentication failed: %d",
+ problem);
+
+ krb5_cleanup_proc(authctxt);
+
+ if (options.kerberos_or_local_passwd)
+ return (-1);
+ else
+ return (0);
+ }
+ return (authctxt->valid ? 1 : 0);
+}
+
+void
+krb5_cleanup_proc(Authctxt *authctxt)
+{
+ debug("krb5_cleanup_proc called");
+ if (authctxt->krb5_fwd_ccache) {
+ krb5_cc_destroy(authctxt->krb5_ctx, authctxt->krb5_fwd_ccache);
+ authctxt->krb5_fwd_ccache = NULL;
+ }
+ if (authctxt->krb5_user) {
+ krb5_free_principal(authctxt->krb5_ctx, authctxt->krb5_user);
+ authctxt->krb5_user = NULL;
+ }
+ if (authctxt->krb5_ctx) {
+ krb5_free_context(authctxt->krb5_ctx);
+ authctxt->krb5_ctx = NULL;
+ }
+}
+
+#ifndef HEIMDAL
+krb5_error_code
+ssh_krb5_cc_gen(krb5_context ctx, krb5_ccache *ccache) {
+ int tmpfd, ret, oerrno;
+ char ccname[40];
+ mode_t old_umask;
+
+ ret = snprintf(ccname, sizeof(ccname),
+ "FILE:/tmp/krb5cc_%d_XXXXXXXXXX", geteuid());
+ if (ret < 0 || (size_t)ret >= sizeof(ccname))
+ return ENOMEM;
+
+ old_umask = umask(0177);
+ tmpfd = mkstemp(ccname + strlen("FILE:"));
+ oerrno = errno;
+ umask(old_umask);
+ if (tmpfd == -1) {
+ logit("mkstemp(): %.100s", strerror(oerrno));
+ return oerrno;
+ }
+
+ if (fchmod(tmpfd,S_IRUSR | S_IWUSR) == -1) {
+ oerrno = errno;
+ logit("fchmod(): %.100s", strerror(oerrno));
+ close(tmpfd);
+ return oerrno;
+ }
+ close(tmpfd);
+
+ return (krb5_cc_resolve(ctx, ccname, ccache));
+}
+#endif /* !HEIMDAL */
+#endif /* KRB5 */