aboutsummaryrefslogtreecommitdiff
From 0d85bbd42ddcd442864a9ba4719aca8b70d68048 Mon Sep 17 00:00:00 2001
From: Alexey Abramov <levenson@mmer.org>
Date: Fri, 22 Apr 2022 11:32:15 +0200
Subject: [PATCH] Trust guix store directory

To be able to execute binaries defined in OpenSSH configuration, we
need to tell OpenSSH that we can trust Guix store objects. safe_path
procedure takes a canonical path and for each component, walking
upwards, checks ownership and permissions constrains which are: must
be owned by root, not writable by group or others.
---
 misc.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/misc.c b/misc.c
index 0134d69..7131d5e 100644
--- a/misc.c
+++ b/misc.c
@@ -2146,6 +2146,7 @@ int
 safe_path(const char *name, struct stat *stp, const char *pw_dir,
     uid_t uid, char *err, size_t errlen)
 {
+        static const char guix_store[] = @STORE_DIRECTORY@;
 	char buf[PATH_MAX], homedir[PATH_MAX];
 	char *cp;
 	int comparehome = 0;
@@ -2178,6 +2179,10 @@ safe_path(const char *name, struct stat *stp, const char *pw_dir,
 		}
 		strlcpy(buf, cp, sizeof(buf));
 
+		/* If we are past the Guix store then we can stop */
+		if (strcmp(guix_store, buf) == 0)
+			break;
+
 		if (stat(buf, &st) == -1 ||
 		    (!platform_sys_dir_uid(st.st_uid) && st.st_uid != uid) ||
 		    (st.st_mode & 022) != 0) {
-- 
2.34.0