added setuid command wrapper

1 files changed, 54 insertions, 0 deletions

diff --git a/suidcmd.c b/suidcmd.c
new file mode 100644
index 0000000..0998f41
--- /dev/null
+++ b/suidcmd.c
@@ -0,0 +1,54 @@
+/*
+ * build with: gcc -std=c99 -D_GNU_SOURCE=1 -Wall -O2 -ffunction-sections -fdata-sections -fomit-frame-pointer ./suidcmd.c -o ./suidcmd
+ * strip -s ./suidcmd
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+
+#ifndef CMD
+#define CMD "/usr/sbin/ether-wake"
+#endif
+
+int main(int argc, char** argv)
+{
+  uid_t ruid, euid, suid;
+
+  if (getresuid(&ruid, &euid, &suid) != 0) {
+    perror("getresuid()");
+  } else {
+    printf("%s: RUID:%u , EUID:%u , SUID:%u\n", argv[0], ruid, euid, suid);
+  }
+
+  if (setuid(0) != 0) {
+    perror("setuid(0)");
+  } else printf("%s: setuid(0)\n", argv[0]);
+
+  char* cmd = NULL;
+  if (asprintf(&cmd, "%s", CMD) <= 0) {
+    fprintf(stderr, "%s: asprintf(\"%s\") error\n", argv[0], CMD);
+    return 1;
+  }
+
+  char* prev_cmd = NULL;
+  for (int i = 1; i < argc; ++i) {
+    prev_cmd = cmd;
+    if (asprintf(&cmd, "%s %s", prev_cmd, argv[i]) < 0) {
+      fprintf(stderr, "%s: asprintf(\"%s\") error\n", argv[0], argv[i]);
+      return 1;
+    }
+    free(prev_cmd);
+  }
+
+  printf("system(\"%s\")\n", cmd);
+  int retval = -1;
+  switch ( (retval = system(cmd)) ) {
+    case -1: fprintf(stderr, "%s: could not create child process..\n", argv[0]); return 1;
+    case 127: fprintf(stderr, "%s: could not execute shell (child process)..\n", argv[0]); return 1;
+    default:
+      printf("%s: child process returned with: %d\n", argv[0], retval);
+  }
+  return 0;
+}