Add a naive remote detection

2 files changed, 23 insertions, 13 deletions

diff --git a/README.md b/README.md
index dec9818..575d2e8 100644
--- a/README.md
+++ b/README.md
@@ -117,7 +117,8 @@ terminal is insecure, which is what Windows RDP does regarding remote UAC consen
 mkdir build
 cd build
 cmake ..
-sudo ./secdesktop password test # mode prompt
+chown root ./secdesk && chmod 4755 ./secdesk
+./secdesktop password test # mode prompt
 ```
 
 The code is ugly: it is written in 4 hours. I will try to make it pretty.
diff --git a/main.c b/main.c
index a05f0a1..0d3a52e 100644
--- a/main.c
+++ b/main.c
@@ -5,6 +5,7 @@
 #include <string.h>
 #include <signal.h>
 #include <errno.h>
+#include <stdlib.h>
 #include <sys/wait.h>
 
 struct auth_env a_env;
@@ -70,21 +71,29 @@ int main(int argc, char **argv) {
         sigaction(SIGINT, &sa, NULL);
         sigaction(SIGTERM, &sa, NULL);
 
-        int r = sd_setup();
-        if (r == -1) {
-            sd_cleanup();
-            return 13;
-        }
-        if (r) {
-            sd_cleanup();
+        int r;
+        /* Very naive way to determine console and remote sessions.
+         * Better to use PAM_RHOST, ConsoleKit, or systemd-logind. */
+        if (getenv("SSH_CONNECTION")) {
             r = main_consent(0);
         } else {
-            dprintf(p_env.err, "Complete authorization on TTY %d by running `chvt %d`.\n",
-                    p_env.vt,
-                    p_env.vt);
-            r = main_consent(1);
-            sd_cleanup();
+            r = sd_setup();
+            if (r == -1) {
+                sd_cleanup();
+                return 13;
+            }
+            if (r) {
+                sd_cleanup();
+                r = main_consent(0);
+            } else {
+                dprintf(p_env.err, "Complete authorization on TTY %d by running `chvt %d`.\n",
+                        p_env.vt,
+                        p_env.vt);
+                r = main_consent(1);
+                sd_cleanup();
+            }
         }
+
         return r;
     }
     if (chld == -1) {