- (djm) Pull in auth-krb5.c from OpenBSD CVS. NB. it is not currently used.

1 files changed, 259 insertions, 0 deletions

diff --git a/auth-krb5.c b/auth-krb5.c
new file mode 100644
index 00000000..08c91745
--- /dev/null
+++ b/auth-krb5.c
@@ -0,0 +1,259 @@
+/*
+ *    Kerberos v5 authentication and ticket-passing routines.
+ * 
+ * $FreeBSD: src/crypto/openssh/auth-krb5.c,v 1.6 2001/02/13 16:58:04 assar Exp $
+ * $OpenBSD: auth-krb5.c,v 1.1 2001/06/26 16:15:23 dugsong Exp $
+ */
+
+#include "includes.h"
+#include "ssh.h"
+#include "ssh1.h"
+#include "packet.h"
+#include "xmalloc.h"
+#include "log.h"
+#include "servconf.h"
+#include "uidswap.h"
+#include "auth.h"
+
+#ifdef KRB5
+#include <krb5.h>
+
+extern ServerOptions	 options;
+
+static int
+krb5_init(void *context)
+{
+	Authctxt *authctxt = (Authctxt *)context;
+	krb5_error_code problem;
+	static int cleanup_registered = 0;
+	
+	if (authctxt->krb5_ctx == NULL) {
+		problem = krb5_init_context(&authctxt->krb5_ctx);
+		if (problem)
+			return (problem);
+		krb5_init_ets(authctxt->krb5_ctx);
+	}
+	if (!cleanup_registered) {
+		fatal_add_cleanup(krb5_cleanup_proc, authctxt);
+		cleanup_registered = 1;
+	}
+	return (0);
+}
+
+/*
+ * Try krb5 authentication. server_user is passed for logging purposes
+ * only, in auth is received ticket, in client is returned principal
+ * from the ticket
+ */
+int 
+auth_krb5(Authctxt *authctxt, krb5_data *auth, char **client)
+{
+	krb5_error_code problem;
+	krb5_principal server;
+	krb5_data reply;
+	krb5_ticket *ticket;
+	int fd;
+	
+	server = NULL;
+	ticket = NULL;
+	reply.length = 0;
+	
+	problem = krb5_init(authctxt);
+	if (problem) 
+		goto err;
+	
+	problem = krb5_auth_con_init(authctxt->krb5_ctx,
+	    &authctxt->krb5_auth_ctx);
+	if (problem)
+		goto err;
+	
+	fd = packet_get_connection_in();
+	problem = krb5_auth_con_setaddrs_from_fd(authctxt->krb5_ctx,
+	    authctxt->krb5_auth_ctx, &fd);
+	if (problem)
+		goto err;
+	
+	problem = krb5_sname_to_principal(authctxt->krb5_ctx,  NULL, NULL ,
+	    KRB5_NT_SRV_HST, &server);
+	if (problem)
+		goto err;
+	
+	problem = krb5_rd_req(authctxt->krb5_ctx, &authctxt->krb5_auth_ctx,
+	    auth, server, NULL, NULL, &ticket);
+	if (problem)
+		goto err;
+	
+	problem = krb5_copy_principal(authctxt->krb5_ctx, ticket->client,
+	    &authctxt->krb5_user);
+	if (problem)
+		goto err;
+	
+	/* if client wants mutual auth */
+	problem = krb5_mk_rep(authctxt->krb5_ctx, authctxt->krb5_auth_ctx,
+	    &reply);
+	if (problem)
+		goto err;
+	
+	/* Check .k5login authorization now. */
+	if (!krb5_kuserok(authctxt->krb5_ctx, authctxt->krb5_user,
+	    authctxt->pw->pw_name))
+		goto err;
+	
+	if (client)
+		krb5_unparse_name(authctxt->krb5_ctx, authctxt->krb5_user,
+		    client);
+	
+	packet_start(SSH_SMSG_AUTH_KERBEROS_RESPONSE);
+	packet_put_string((char *) reply.data, reply.length);
+	packet_send();
+	packet_write_wait();
+	
+ err:
+	if (server)
+		krb5_free_principal(authctxt->krb5_ctx, server);
+	if (ticket)
+		krb5_free_ticket(authctxt->krb5_ctx, ticket);
+	if (reply.length)
+		xfree(reply.data);
+	
+	if (problem) {
+		debug("Kerberos v5 authentication failed: %s",
+		    krb5_get_err_text(authctxt->krb5_ctx, problem));
+		return (0);
+	}
+	return (1);
+}
+
+int
+auth_krb5_tgt(Authctxt *authctxt, krb5_data *tgt)
+{
+	krb5_error_code problem;
+	krb5_ccache ccache = NULL;
+	char *pname;
+	
+	if (authctxt->pw == NULL || authctxt->krb5_user == NULL)
+		return (0);
+	
+	temporarily_use_uid(authctxt->pw);
+	
+	problem = krb5_cc_gen_new(authctxt->krb5_ctx, &krb5_fcc_ops, &ccache);
+	if (problem)
+		goto fail;
+	
+	problem = krb5_cc_initialize(authctxt->krb5_ctx, ccache,
+	    authctxt->krb5_user);
+	if (problem)
+		goto fail;
+	
+	problem = krb5_rd_cred2(authctxt->krb5_ctx, authctxt->krb5_auth_ctx,
+	    ccache, tgt);
+	if (problem)
+		goto fail;
+	
+	authctxt->krb5_fwd_ccache = ccache;
+	ccache = NULL;
+	
+	authctxt->krb5_ticket_file = (char *)krb5_cc_get_name(authctxt->krb5_ctx, authctxt->krb5_fwd_ccache);
+	
+	problem = krb5_unparse_name(authctxt->krb5_ctx, authctxt->krb5_user,
+	    &pname);
+	if (problem)
+		goto fail;
+	
+	debug("Kerberos v5 TGT accepted (%s)", pname);
+	
+	restore_uid();
+	
+	return (1);
+	
+ fail:
+	if (problem)
+		debug("Kerberos v5 TGT passing failed: %s",
+		    krb5_get_err_text(authctxt->krb5_ctx, problem));
+	if (ccache)
+		krb5_cc_destroy(authctxt->krb5_ctx, ccache);
+	
+	restore_uid();
+	
+	return (0);
+}
+
+int
+auth_krb5_password(Authctxt *authctxt, const char *password)
+{
+	krb5_error_code problem;
+	
+	if (authctxt->pw == NULL)
+		return (0);
+	
+	temporarily_use_uid(authctxt->pw);
+	
+	problem = krb5_init(authctxt);
+	if (problem)
+		goto out;
+	
+	problem = krb5_parse_name(authctxt->krb5_ctx, authctxt->pw->pw_name,
+		    &authctxt->krb5_user);
+	if (problem)
+		goto out;
+	
+	problem = krb5_cc_gen_new(authctxt->krb5_ctx, &krb5_mcc_ops,
+	    &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_verify_user(authctxt->krb5_ctx, authctxt->krb5_user,
+	    authctxt->krb5_fwd_ccache, password, 1, NULL);
+	if (problem)
+		goto out;
+	
+	authctxt->krb5_ticket_file = (char *)krb5_cc_get_name(authctxt->krb5_ctx, authctxt->krb5_fwd_ccache);
+	
+ out:
+	restore_uid();
+	
+	if (problem) {
+		debug("Kerberos password authentication failed: %s",
+		    krb5_get_err_text(authctxt->krb5_ctx, problem));
+		
+		krb5_cleanup_proc(authctxt);
+		
+		if (options.kerberos_or_local_passwd)
+			return (-1);
+		else
+			return (0);
+	}
+	return (1);
+}
+
+void
+krb5_cleanup_proc(void *context)
+{
+	Authctxt *authctxt = (Authctxt *)context;
+	
+	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_auth_ctx) {
+		krb5_auth_con_free(authctxt->krb5_ctx,
+		    authctxt->krb5_auth_ctx);
+		authctxt->krb5_auth_ctx = NULL;
+	}
+	if (authctxt->krb5_ctx) {
+		krb5_free_context(authctxt->krb5_ctx);
+		authctxt->krb5_ctx = NULL;
+	}
+}
+
+#endif /* KRB5 */