[systemd-devel] [PATCH][RFC] bus-proxy: add support for "GetConnectionCredentials" method

[Lukasz Skalski]

GetConnectionCredentials method was added to dbus-1 specification
more than one year ago. This method should return "[...] as many
credentials as possible for the process connected to the server",
but at this moment only "UnixUserID" and "ProcessID" are defined
by the specification. We should add support for next credentials
after extending dbus-1 spec.

diff --git a/src/bus-proxyd/driver.c b/src/bus-proxyd/driver.c
index bc2c0c8..8ab4a16 100644
--- a/src/bus-proxyd/driver.c
+++ b/src/bus-proxyd/driver.c
@@ -116,6 +116,10 @@ int bus_proxy_process_driver(sd_bus *a, sd_bus *b, sd_bus_message *m, SharedPoli
                         "  <method name=\"RemoveMatch\">\n"
                         "   <arg type=\"s\" direction=\"in\"/>\n"
                         "  </method>\n"
+                        "  <method name=\"GetConnectionCredentials\">\n"
+                        "   <arg type=\"s\" direction=\"in\"/>\n"
+                        "   <arg type=\"a{sv}\" direction=\"out\"/>\n"
+                        "  </method>\n"
                         "  <method name=\"GetConnectionSELinuxSecurityContext\">\n"
                         "   <arg type=\"s\" direction=\"in\"/>\n"
                         "   <arg type=\"ay\" direction=\"out\"/>\n"
@@ -219,6 +223,40 @@ int bus_proxy_process_driver(sd_bus *a, sd_bus *b, sd_bus_message *m, SharedPoli
 
                 return synthetic_reply_method_return(m, NULL);
 
+        } else if (sd_bus_message_is_method_call(m, "org.freedesktop.DBus", "GetConnectionCredentials")) {
+                _cleanup_bus_creds_unref_ sd_bus_creds *creds = NULL;
+                _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
+                _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
+
+                if (!sd_bus_message_has_signature(m, "s"))
+                        return synthetic_reply_method_error(m, &SD_BUS_ERROR_MAKE_CONST(SD_BUS_ERROR_INVALID_ARGS, "Invalid parameters"));
+
+                r = get_creds_by_message(a, m, SD_BUS_CREDS_PID|SD_BUS_CREDS_EUID, &creds, &error);
+                if (r < 0)
+                        return synthetic_reply_method_errno(m, r, &error);
+
+                r = sd_bus_message_new_method_return(m, &reply);
+                if (r < 0)
+                        return synthetic_reply_method_errno(m, r, NULL);
+
+                r = sd_bus_message_open_container(reply, 'a', "{sv}");
+                if (r < 0)
+                        return synthetic_reply_method_errno(m, r, NULL);
+
+                r = sd_bus_message_append(reply, "{sv}", "ProcessID", "u", (uint32_t) creds->pid);
+                if (r < 0)
+                        return synthetic_reply_method_errno(m, r, NULL);
+
+                r = sd_bus_message_append(reply, "{sv}", "UnixUserID", "u", (uint32_t) creds->euid);
+                if (r < 0)
+                        return synthetic_reply_method_errno(m, r, NULL);
+
+                r = sd_bus_message_close_container(reply);
+                if (r < 0)
+                        return synthetic_reply_method_errno(m, r, NULL);
+
+                return synthetic_driver_send(m->bus, reply);
+
         } else if (sd_bus_message_is_method_call(m, "org.freedesktop.DBus", "GetConnectionSELinuxSecurityContext")) {
                 _cleanup_bus_creds_unref_ sd_bus_creds *creds = NULL;
                 _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
diff --git a/src/bus-proxyd/synthesize.c b/src/bus-proxyd/synthesize.c
index e1b0fd3..d370a05 100644
--- a/src/bus-proxyd/synthesize.c
+++ b/src/bus-proxyd/synthesize.c
@@ -38,7 +38,7 @@
 #include "bus-control.h"
 #include "synthesize.h"
 
-static int synthetic_driver_send(sd_bus *b, sd_bus_message *m) {
+int synthetic_driver_send(sd_bus *b, sd_bus_message *m) {
         int r;
 
         assert(b);
diff --git a/src/bus-proxyd/synthesize.h b/src/bus-proxyd/synthesize.h
index a55f171..e850350 100644
--- a/src/bus-proxyd/synthesize.h
+++ b/src/bus-proxyd/synthesize.h
@@ -23,6 +23,8 @@
 
 #include "sd-bus.h"
 
+int synthetic_driver_send(sd_bus *b, sd_bus_message *m);
+
 int synthetic_reply_method_return(sd_bus_message *call, const char *types, ...);
 int synthetic_reply_method_return_strv(sd_bus_message *call, char **l);
 
-- 
1.9.3