meow

1 files changed, 39 insertions, 0 deletions

diff --git a/no_shell.c b/no_shell.c
new file mode 100644
index 0000000..a06c10a
--- /dev/null
+++ b/no_shell.c
@@ -0,0 +1,39 @@
+/* /usr/local/sbin/no_shell
+   friendly restricted shell for my mail server with optional password change
+   version v3.1 
+*/
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <syslog.h>
+
+int main(void) {
+    const char *username = getenv("USER");
+    if (!username || !*username)
+        username = "(unknown)";
+
+    fputs("No-no-no, no shell for you\n", stdout);
+    fputs("For shell access contact lain@lainmail.xyz\n\n", stdout);
+    printf("Would you like to change your password, %s? [y/N]: ", username);
+    fflush(stdout);
+
+    char choice = 0;
+    scanf(" %c", &choice);
+
+    openlog("no_shell", LOG_PID | LOG_NDELAY, LOG_AUTH);
+    syslog(LOG_NOTICE, "login attempt for %s", username);
+    closelog();
+
+    if (choice == 'y' || choice == 'Y') {
+        printf("\nStarting password change for %s...\n\n", username);
+        fflush(stdout);
+        execl("/usr/bin/passwd", "passwd", username, (char *)NULL);
+        perror("execl");
+        exit(1);
+    }
+
+    printf("\nOkay, goodbye!\n");
+    fflush(stdout);
+    return 2;
+}