From dc3867058d672f92598166eacab6ca1a560d50ec Mon Sep 17 00:00:00 2001
From: Micah Morton <mortonm@chromium.org>
Date: Fri, 20 Apr 2018 11:54:26 -0700
Subject: [PATCH] Allow pppd to start as non-root.

This patch adds #ifndef macros in 2 spots in order to allow pppd to be
spawned as a non-root user with only runtime capabilities (e.g.
CAP_NET_{RAW/ADMIN}) instead of giving pppd full root privileges. This
is helpful if pppd is itself spawned by a non-root user and the use of
file permissions (e.g. setuid-root) on the pppd binary is not a
desirable solution.
---
 pppd/main.c    | 2 ++
 pppd/options.c | 2 ++
 2 files changed, 4 insertions(+)

diff --git a/pppd/main.c b/pppd/main.c
index 87a5d29..fc9b322 100644
--- a/pppd/main.c
+++ b/pppd/main.c
@@ -359,6 +359,7 @@ main(int argc, char *argv[])
     if (debug)
 	setlogmask(LOG_UPTO(LOG_DEBUG));
 
+#ifndef ALLOW_START_AS_NON_ROOT
     /*
      * Check that we are running as root.
      */
@@ -367,6 +368,7 @@ main(int argc, char *argv[])
 		     argv[0]);
 	exit(EXIT_NOT_ROOT);
     }
+#endif
 
     if (!ppp_available()) {
 	option_error("%s", no_ppp_msg);
diff --git a/pppd/options.c b/pppd/options.c
index f8d6c00..2272912 100644
--- a/pppd/options.c
+++ b/pppd/options.c
@@ -694,11 +694,13 @@ process_option(option_t *opt, char *cmd, char **argv)
 		     opt->name, optopt);
 	return 0;
     }
+#ifndef ALLOW_START_AS_NON_ROOT
     if ((opt->flags & OPT_PRIV) && !privileged_option) {
 	option_error("using the %s%s requires root privilege",
 		     opt->name, optopt);
 	return 0;
     }
+#endif
     if ((opt->flags & OPT_ENABLE) && *(bool *)(opt->addr2) == 0) {
 	option_error("%s%s is disabled", opt->name, optopt);
 	return 0;
-- 
2.30.1