From 2104b80446dfd4bbc26d0d75691de4b4603a30f5 Mon Sep 17 00:00:00 2001
From: Lennart Poettering <lennart@poettering.net>
Date: Fri, 9 Jan 2004 20:48:55 +0000
Subject: implemented user id switching some locking fixups

git-svn-id: file:///home/lennart/svn/public/ivam2/trunk@24 dbf6933d-3bce-0310-9bcc-ed052ba35b35
---
 src/lock.c | 22 +++++++++++++++++++++-
 1 file changed, 21 insertions(+), 1 deletion(-)

(limited to 'src/lock.c')

diff --git a/src/lock.c b/src/lock.c
index 42ad213..efce0bb 100644
--- a/src/lock.c
+++ b/src/lock.c
@@ -8,6 +8,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <inttypes.h>
+#include <pwd.h>
 
 #include <libdaemon/dlog.h>
 
@@ -35,6 +36,7 @@ int device_lock(const char *dev) {
     int fd;
     const char *path, *temp;
     char buf[100];
+    char uidbuf[32];
 
     if (stat(LOCK_PATH, &st) != 0 || !S_ISDIR(st.st_mode)) {
         daemon_log(LOG_ERR, "Failed to lock device, directory "LOCK_PATH" not existent.");
@@ -45,6 +47,9 @@ int device_lock(const char *dev) {
     temp = tempfile(path);
 
     for (;;) {
+        mode_t u;
+        struct passwd* pw;
+        char *username;
         
         if ((fd = open(path, O_RDONLY)) < 0) {
             if (errno != ENOENT) {
@@ -87,18 +92,33 @@ int device_lock(const char *dev) {
                 }
             }
         }
+
+        u = umask(0033);
+        fd = open(temp, O_WRONLY | O_CREAT | O_EXCL, 0666);
+        umask(u);
         
-        if ((fd = open(temp, O_WRONLY | O_CREAT | O_EXCL, 0666)) < 0) {
+        if (fd < 0) {
             daemon_log(LOG_ERR, "Failed to create temporary lock file: %s", strerror(errno));
             return -1;
         }
 
+        if ((pw = getpwuid(target_uid)))
+            username = pw->pw_name;
+        else
+            snprintf(username = uidbuf, sizeof(uidbuf), "%lu", (unsigned long) target_uid);
+
         snprintf(buf, sizeof(buf), "%10lu %s %.20s\n", (unsigned long) getpid(), appname, username);
         if (loop_write(fd, buf, strlen(buf)) < 0) {
             daemon_log(LOG_ERR, "Failed to write to temporary lock file: %s", strerror(errno));
             close(fd);
             return -1;
         }
+
+        if (fchown(fd, target_uid, target_gid) < 0) {
+            daemon_log(LOG_ERR, "Failed to change owners of temporary lock file: %s", strerror(errno));
+            close(fd);
+            return -1;
+        }
     
         close(fd);
 
-- 
cgit