1 files changed, 44 insertions, 0 deletions
diff --git a/configd/src/apps/su/main.cpp b/configd/src/apps/su/main.cpp
new file mode 100644
index 00000000000..7baa726d630
--- /dev/null
+++ b/configd/src/apps/su/main.cpp
@@ -0,0 +1,44 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <stdlib.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <pwd.h>
+#include <grp.h>
+
+/**
+ * small utility to use instead of "su" when we want to just
+ * switch to the "yahoo" user without any more fuss
+ **/
+
+int main(int argc, char** argv)
+{
+    if (argc < 2) {
+        fprintf(stderr, "missing arguments, usage: run-as-yahoo <cmd> [args ...]");
+        exit(1);
+    }
+    struct passwd *p = getpwnam("yahoo");
+    if (p == NULL) {
+        perror("FATAL error: user 'yahoo' missing in passwd file");
+        exit(1);
+    }
+    gid_t g = p->pw_gid;
+    uid_t u = p->pw_uid;
+
+    if (setgid(g) != 0) {
+        perror("FATAL error: could not change group id");
+        exit(1);
+    }
+    size_t listsize = 1;
+    gid_t grouplist[1] = { g };
+    if (setgroups(listsize, grouplist) != 0) {
+        perror("FATAL error: could not setgroups");
+        exit(1);
+    }
+    if (setuid(u) != 0) {
+        perror("FATAL error: could not change user id");
+        exit(1);
+    }
+    execvp(argv[1], &argv[1]);
+    perror("FATAL error: execvp failed");
+    exit(1);
+}