+
+/* MIT kerberos uses replay cache checks even during credential verification
+ * (i.e. in krb5_verify_init_creds()), which is obviosuly useless. In order to
+ * avoid problems with multiple apache processes accessing the same rcache file
+ * we had to use this call instead, which is only a bit modified version of
+ * krb5_verify_init_creds() */
+static krb5_error_code
+verify_krb5_init_creds(request_rec *r, krb5_context context, krb5_creds *creds,
+ krb5_principal ap_req_server, krb5_keytab ap_req_keytab)
+{
+ krb5_error_code ret;
+ krb5_data req;
+ krb5_ccache local_ccache = NULL;
+ krb5_creds *new_creds = NULL;
+ krb5_auth_context auth_context = NULL;
+ krb5_keytab keytab = NULL;
+ char *server_name;
+
+ memset(&req, 0, sizeof(req));
+
+ if (ap_req_keytab == NULL) {
+ ret = krb5_kt_default (context, &keytab);
+ if (ret)
+ return ret;
+ } else
+ keytab = ap_req_keytab;
+
+ ret = krb5_cc_resolve(context, "MEMORY:", &local_ccache);
+ if (ret) {
+ log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r,
+ "krb5_cc_resolve() failed when verifying KDC");
+ return ret;
+ }
+
+ ret = krb5_cc_initialize(context, local_ccache, creds->client);
+ if (ret) {
+ log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r,
+ "krb5_cc_initialize() failed when verifying KDC");
+ goto end;
+ }
+
+ ret = krb5_cc_store_cred (context, local_ccache, creds);
+ if (ret) {
+ log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r,
+ "krb5_cc_initialize() failed when verifying KDC");
+ goto end;
+ }
+
+ ret = krb5_unparse_name(context, ap_req_server, &server_name);
+ if (ret) {
+ log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r,
+ "krb5_unparse_name() failed when verifying KDC");
+ goto end;
+ }
+ log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r,
+ "Trying to verify authenticity of KDC using principal %s", server_name);
+ free(server_name);
+
+ if (!krb5_principal_compare (context, ap_req_server, creds->server)) {
+ krb5_creds match_cred;
+
+ memset (&match_cred, 0, sizeof(match_cred));
+
+ match_cred.client = creds->client;
+ match_cred.server = ap_req_server;
+
+ ret = krb5_get_credentials (context, 0, local_ccache,
+ &match_cred, &new_creds);
+ if (ret) {
+ log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r,
+ "krb5_get_credentials() failed when verifying KDC");
+ goto end;
+ }
+ creds = new_creds;
+ }
+
+ ret = krb5_mk_req_extended (context, &auth_context, 0, NULL, creds, &req);
+ if (ret) {
+ log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r,
+ "krb5_mk_req_extended() failed when verifying KDC");
+ goto end;
+ }
+
+ krb5_auth_con_free (context, auth_context);
+ auth_context = NULL;
+ ret = krb5_auth_con_init(context, &auth_context);
+ if (ret) {
+ log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r,
+ "krb5_auth_con_init() failed when verifying KDC");
+ goto end;
+ }
+ /* use KRB5_AUTH_CONTEXT_DO_SEQUENCE to skip replay cache checks */
+ krb5_auth_con_setflags(context, auth_context, KRB5_AUTH_CONTEXT_DO_SEQUENCE);
+
+ ret = krb5_rd_req (context, &auth_context, &req, ap_req_server,
+ keytab, 0, NULL);
+ if (ret) {
+ log_rerror(APLOG_MARK, APLOG_DEBUG, 0, r,
+ "krb5_rd_req() failed when verifying KDC");
+ goto end;
+ }
+
+end:
+#ifdef HEIMDAL
+ /* XXX Do I ever want to support Heimdal 0.4 ??? */
+ krb5_data_free(&req);
+#else
+ krb5_free_data_contents(context, &req);
+#endif
+ if (auth_context)
+ krb5_auth_con_free (context, auth_context);
+ if (new_creds)
+ krb5_free_creds (context, new_creds);
+ if (ap_req_keytab == NULL && keytab)
+ krb5_kt_close (context, keytab);
+ if (local_ccache)
+ krb5_cc_destroy (context, local_ccache);
+
+ return ret;
+}
+