(krb5_ticket_get_authorization_data_type): understand

KRB5_AUTHDATA_IF_RELEVANT and KRB5_AUTHDATA_AND_OR (but have
KRB5_AUTHDATA_KDC_ISSUED commented out for now)


git-svn-id: svn://svn.h5l.se/heimdal/trunk/heimdal@16247 ec53bebd-3082-4978-b11e-865c3cabbd6b

lib/krb5/ticket.c

@@ -97,6 +97,143 @@ krb5_ticket_get_server(krb5_context context,
     return krb5_copy_principal(context, ticket->server, server);
 }
 
+static int
+find_type_in_ad(krb5_context context,
+		int type, 
+		krb5_data *data,
+		int *found,
+		int failp,
+		krb5_keyblock *sessionkey,
+		const AuthorizationData *ad,
+		int level)
+{
+    krb5_error_code ret = ENOENT;
+    int i;
+
+    if (level > 9) {
+	krb5_set_error_string(context, "Authorization data nested deeper "
+			      "then %d levels, stop searching", level);
+	ret = ENOENT; /* XXX */
+	goto out;
+    }
+
+    /*
+     * Only copy out the element the first time we get to it, we need
+     * to run over the whole authorization data fields to check if
+     * there are any container clases we need to care about.
+     */
+    for (i = 0; i < ad->len; i++) {
+	if (!*found && ad->val[i].ad_type == type) {
+	    ret = copy_octet_string(&ad->val[i].ad_data, data);
+	    if (ret) {
+		krb5_set_error_string(context, "malloc - out of memory");
+		goto out;
+	    }
+	    *found = 1;
+	    continue;
+	}
+	switch (ad->val[i].ad_type) {
+	case KRB5_AUTHDATA_IF_RELEVANT: {
+	    AuthorizationData child;
+	    ret = decode_AuthorizationData(ad->val[i].ad_data.data,
+					   ad->val[i].ad_data.length,
+					   &child,
+					   NULL);
+	    if (ret) {
+		krb5_set_error_string(context, "Failed to decode "
+				      "IF_RELEVANT with %d", ret);
+		goto out;
+	    }
+	    ret = find_type_in_ad(context, type, data, found, 0, sessionkey,
+				  &child, level + 1);
+	    free_AuthorizationData(&child);
+	    if (ret)
+		goto out;
+	    break;
+	}
+#if 0 /* XXX test */
+	case KRB5_AUTHDATA_KDC_ISSUED: {
+	    AD_KDCIssued child;
+
+	    ret = decode_AD_KDCIssued(ad->val[i].ad_data.data,
+				      ad->val[i].ad_data.length,
+				      &child,
+				      NULL);
+	    if (ret) {
+		krb5_set_error_string(context, "Failed to decode "
+				      "AD_KDCIssued with %d", ret);
+		goto out;
+	    }
+	    if (failp) {
+		krb5_boolean valid;
+		krb5_data buf;
+		size_t len;
+
+		ASN1_MALLOC_ENCODE(AuthorizationData, buf.data, buf.length, 
+				   &child.elements, &len, ret);
+		if (ret) {
+		    free_AD_KDCIssued(&child);
+		    krb5_clear_error_string(context);
+		    goto out;
+		}
+		if(buf.length != len)
+		    krb5_abortx(context, "internal error in ASN.1 encoder");
+
+		ret = krb5_c_verify_checksum(context, sessionkey, 19, &buf,
+					     &child.ad_checksum, &valid);
+		krb5_data_free(&buf);
+		if (ret) {
+		    free_AD_KDCIssued(&child);
+		    goto out;
+		}
+		if (!valid) {
+		    krb5_clear_error_string(context);
+		    ret = ENOENT;
+		    free_AD_KDCIssued(&child);
+		    goto out;
+		}
+	    }
+	    ret = find_type_in_ad(context, type, data, found, failp, sessionkey,
+				  &child.elements, level + 1);
+	    free_AD_KDCIssued(&child);
+	    if (ret)
+		goto out;
+	    break;
+	}
+#endif
+	case KRB5_AUTHDATA_AND_OR:
+	    if (!failp)
+		break;
+	    krb5_set_error_string(context, "Authorization data contains "
+				  "AND-OR element that is unknown to the "
+				  "application");
+	    ret = ENOENT; /* XXX */
+	    goto out;
+	default:
+	    if (!failp)
+		break;
+	    krb5_set_error_string(context, "Authorization data contains "
+				  "unknown type (%d) ", ad->val[i].ad_type);
+	    ret = ENOENT; /* XXX */
+	    goto out;
+	}
+    }
+out:
+    if (ret) {
+	if (*found) {
+	    krb5_data_free(data);
+	    *found = 0;
+	}
+    }
+    return ret;
+}
+
+/*
+ * Extract the authorization data type of `type' from the
+ * 'ticket'. Store the field in `data'. This function is to use for
+ * kerberos applications
+ */
+
 krb5_error_code KRB5_LIB_FUNCTION
 krb5_ticket_get_authorization_data_type(krb5_context context,
 					krb5_ticket *ticket,
@@ -104,22 +241,25 @@ krb5_ticket_get_authorization_data_type(krb5_context context,
 					krb5_data *data)
 {
     AuthorizationData *ad;
-    int i;
+    krb5_error_code ret;
+    int found = 0;
 
-    data->length = 0;
+    krb5_data_zero(data);
-    data->data = NULL;
 
     ad = ticket->ticket.authorization_data;
-    if (ad == NULL) {
+    if (ticket->ticket.authorization_data == NULL) {
 	krb5_set_error_string(context, "Ticket have not authorization data");
 	return ENOENT; /* XXX */
     }
 
-    for (i = 0; i < ad->len; i++) {
+    ret = find_type_in_ad(context, type, data, &found, 1, &ticket->ticket.key,
-	if (ad->val[i].ad_type == type)
+			  ticket->ticket.authorization_data, 0);
-	    return copy_octet_string(&ad->val[i].ad_data, data);
+    if (ret)
-    }
+	return ret;
-    krb5_set_error_string(context, "Ticket have not authorization "
+    if (!found) {
+	krb5_set_error_string(context, "Ticket have not authorization "
 			  "data of type %d", type);
-    return ENOENT; /* XXX */
+	return ENOENT; /* XXX */
+    }
+    return 0;
 }