IFP: use a list of allowed_uids for authentication

Similar to the PAC responder, the InfoPipe uses a list of UIDs that are
allowed to communicate with the IFP responder.

Reviewed-by: Pavel Březina <pbrezina@redhat.com>
Reviewed-by: Stef Walter <stefw@redhat.com>

1 files changed, 46 insertions, 1 deletions

diff --git a/src/responder/ifp/ifpsrv_util.c b/src/responder/ifp/ifpsrv_util.c
index e16d36279..2bce20186 100644
--- a/src/responder/ifp/ifpsrv_util.c
+++ b/src/responder/ifp/ifpsrv_util.c
@@ -29,6 +29,7 @@ errno_t ifp_req_create(struct sbus_request *dbus_req,
                        struct ifp_req **_ifp_req)
 {
     struct ifp_req *ireq = NULL;
+    errno_t ret;
 
     if (ifp_ctx->sysbus == NULL) {
         DEBUG(SSSDBG_CRIT_FAILURE, "Responder not connected to sysbus!\n");
@@ -43,8 +44,52 @@ errno_t ifp_req_create(struct sbus_request *dbus_req,
     ireq->ifp_ctx = ifp_ctx;
     ireq->dbus_req = dbus_req;
 
+    if (dbus_req->client == -1) {
+        /* We got a sysbus message but couldn't identify the
+         * caller? Bail out! */
+        DEBUG(SSSDBG_CRIT_FAILURE,
+              "BUG: Received a message without a known caller!\n");
+        ret = EACCES;
+        goto done;
+    }
+
+    ret = check_allowed_uids(dbus_req->client,
+                             ifp_ctx->rctx->allowed_uids_count,
+                             ifp_ctx->rctx->allowed_uids);
+    if (ret == EACCES) {
+        DEBUG(SSSDBG_MINOR_FAILURE,
+              "User %"PRIi64" not in ACL\n", dbus_req->client);
+        goto done;
+    } else if (ret != EOK) {
+        DEBUG(SSSDBG_OP_FAILURE,
+              "Cannot check if user %"PRIi64" is present in ACL\n",
+              dbus_req->client);
+        goto done;
+    }
+
     *_ifp_req = ireq;
-    return EOK;
+    ret = EOK;
+done:
+    if (ret != EOK) {
+        talloc_free(ireq);
+    }
+    return ret;
+}
+
+int ifp_req_create_handle_failure(struct sbus_request *dbus_req, errno_t err)
+{
+    if (err == EACCES) {
+        return sbus_request_fail_and_finish(dbus_req,
+                               sbus_error_new(dbus_req,
+                                              DBUS_ERROR_ACCESS_DENIED,
+                                              "User %"PRIi64" not in ACL\n",
+                                              dbus_req->client));
+    }
+
+    return sbus_request_fail_and_finish(dbus_req,
+                                        sbus_error_new(dbus_req,
+                                            DBUS_ERROR_FAILED,
+                                            "Cannot create IFP request\n"));
 }
 
 const char *ifp_path_strip_prefix(const char *path, const char *prefix)