[Toybox] [patch] add su
Strake
strake888 at gmail.com
Mon Aug 12 21:20:40 PDT 2013
>From 4693d474e5cdb95898bb0759eaac6a0d693ee33d Mon Sep 17 00:00:00 2001
From: Strake <strake888 at gmail.com>
Date: Mon, 12 Aug 2013 23:08:53 +0000
Subject: [PATCH] add su
---
toys/pending/su.c | 98 +++++++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 98 insertions(+)
create mode 100644 toys/pending/su.c
diff --git a/toys/pending/su.c b/toys/pending/su.c
new file mode 100644
index 0000000..7f0866d
--- /dev/null
+++ b/toys/pending/su.c
@@ -0,0 +1,98 @@
+/* su.c - switch user
+ *
+ * Copyright 2013 CE Strake <strake888 at gmail.com>
+ *
+ * See http://refspecs.linuxfoundation.org/LSB_4.1.0/LSB-Core-generic/LSB-Core-generic/su.html
+
+USE_SU(NEWTOY(su, "lmpc:s:", TOYFLAG_BIN))
+
+config SU
+ bool "su"
+ default n
+ help
+ usage: su [-lmp] [-c cmd] [-s shell] [user [argu...]]
+
+ Switch to given user, or root if not given, and call a shell with
the given arguments.
+
+ options:
+ -s shell to call
+ -c command to pass to shell with -c
+
+ flags:
+ -l login shell
+ -(m|p) preserve environment
+*/
+
+#define FOR_su
+#include "toys.h"
+
+GLOBALS(
+ char *sArgu;
+ char *cArgu;
+)
+
+extern char **environ;
+
+static void deny () {
+ printf ("Denied\n");
+ xexit ();
+}
+
+void su_main () {
+ char *name, *passhash, **argu, **argv;
+ struct passwd *up;
+ struct spwd *shp;
+ long ii;
+
+ if (toys.optc && strcmp ("-", toys.optargs[0]) == 0) {
+ toys.optflags |= FLAG_l;
+ toys.optc--; toys.optargs++;
+ }
+
+ if (toys.optc) {
+ name = toys.optargs[0];
+ toys.optc--; toys.optargs++;
+ }
+ else name = "root";
+ shp = getspnam (name);
+ if (!shp) perror_exit ("failed to find password");
+
+ switch (shp -> sp_pwdp[0]) {
+ case '!': deny ();
+ case '$': break;
+ default : error_exit ("bad password format");
+ }
+
+ if (read_password (toybuf, sizeof (toybuf), "Password: ") != 0)
perror_exit ("failed to read password");
+
+ passhash = crypt (toybuf, shp -> sp_pwdp);
+ if (!passhash) perror_exit ("failed to compute password hash");
+ for (ii = 0; toybuf[ii]; ii++) toybuf[ii] = 0;
+
+ if (strcmp (passhash, shp -> sp_pwdp) != 0) deny ();
+
+ up = getpwnam (name);
+ if (!up) perror_exit ("failed to getpwnam");
+
+ if (setuid (up -> pw_uid) < 0) perror_exit ("failed to setuid");
+ if (chdir (up -> pw_dir) < 0) perror_exit ("failed to chdir");
+
+ argu = xmalloc (sizeof (char *)*(toys.optc + 4));
+ argv = argu;
+ argv[0] = toys.optflags & FLAG_s ? TT.sArgu : up -> pw_shell;
+ if (toys.optflags & FLAG_c) {
+ argv[1] = toys.optflags & FLAG_l ? "-lc" : "-c";
+ argv[2] = TT.cArgu;
+ argv += 2;
+ }
+ else if (toys.optflags & FLAG_l) (argv++)[1] = "-l";
+ for (ii = 0; ii < toys.optc; ii++) argv[ii + 1] = toys.optargs[ii];
+ if (execve (argu[0], argu,
+ toys.optflags & FLAG_l ? (char *[]){
+ xmsprintf ( "HOME=%s", up -> pw_dir),
+ xmsprintf ("SHELL=%s", up -> pw_shell),
+ xmsprintf ( "USER=%s", up -> pw_name),
+ xmsprintf ( "TERM=%s", getenv ("TERM")),
+ 0
+ } : environ) < 0) perror_exit ("failed to exec %s", argu[0]);
+}
--
1.8.3.4
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