From 1506a4e28f04d2a578b3a11b08c555fc0c5dbd90 Mon Sep 17 00:00:00 2001
From: Jakub Filak <jfilak@redhat.com>
Date: Wed, 15 Apr 2015 15:17:47 +0200
Subject: [PATCH] lib: introduce a new function copy_file_ext

The new function allows to specify UID, GID and open() flags for both
source and destination files.

This function is need to avoid race conditions and symbolic link issues.

Related: #1211835

Signed-off-by: Jakub Filak <jfilak@redhat.com>
---
 src/include/internal_libreport.h |  2 ++
 src/lib/copyfd.c                 | 21 ++++++++++++++++++---
 2 files changed, 20 insertions(+), 3 deletions(-)

diff --git a/src/include/internal_libreport.h b/src/include/internal_libreport.h
index 99f2fe1..e66ca96 100644
--- a/src/include/internal_libreport.h
+++ b/src/include/internal_libreport.h
@@ -152,6 +152,8 @@ off_t copyfd_eof(int src_fd, int dst_fd, int flags);
 off_t copyfd_size(int src_fd, int dst_fd, off_t size, int flags);
 #define copyfd_exact_size libreport_copyfd_exact_size
 void copyfd_exact_size(int src_fd, int dst_fd, off_t size);
+#define copy_file_ext libreport_copy_file_ext
+off_t copy_file_ext(const char *src_name, const char *dst_name, int mode, uid_t uid, gid_t gid, int src_flags, int dst_flags);
 #define copy_file libreport_copy_file
 off_t copy_file(const char *src_name, const char *dst_name, int mode);
 #define copy_file_recursive libreport_copy_file_recursive
diff --git a/src/lib/copyfd.c b/src/lib/copyfd.c
index e9f429d..64fece7 100644
--- a/src/lib/copyfd.c
+++ b/src/lib/copyfd.c
@@ -149,16 +149,16 @@ off_t copyfd_eof(int fd1, int fd2, int flags)
 	return full_fd_action(fd1, fd2, 0, flags);
 }
 
-off_t copy_file(const char *src_name, const char *dst_name, int mode)
+off_t copy_file_ext(const char *src_name, const char *dst_name, int mode, uid_t uid, gid_t gid, int src_flags, int dst_flags)
 {
     off_t r;
-    int src = open(src_name, O_RDONLY);
+    int src = open(src_name, src_flags);
     if (src < 0)
     {
         perror_msg("Can't open '%s'", src_name);
         return -1;
     }
-    int dst = open(dst_name, O_WRONLY | O_TRUNC | O_CREAT, mode);
+    int dst = open(dst_name, dst_flags, mode);
     if (dst < 0)
     {
         close(src);
@@ -167,6 +167,21 @@ off_t copy_file(const char *src_name, const char *dst_name, int mode)
     }
     r = copyfd_eof(src, dst, /*flags:*/ 0);
     close(src);
+    if (uid != (uid_t)-1L)
+    {
+        if (fchown(dst, uid, gid) == -1)
+        {
+            perror_msg("Can't change '%s' ownership to %lu:%lu", dst_name, (long)uid, (long)gid);
+            close(dst);
+            unlink(dst_name);
+            return -1;
+        }
+    }
     close(dst);
     return r;
 }
+
+off_t copy_file(const char *src_name, const char *dst_name, int mode)
+{
+    return copy_file_ext(src_name, dst_name, mode, -1, -1, O_RDONLY, O_WRONLY | O_TRUNC | O_CREAT);
+}
-- 
2.1.0