1 files changed, 30 insertions, 17 deletions

diff --git a/sftp-server.c b/sftp-server.c
index 84264693d..9a66b4de7 100644
--- a/sftp-server.c
+++ b/sftp-server.c
@@ -22,7 +22,7 @@
  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 #include "includes.h"
-RCSID("$OpenBSD: sftp-server.c,v 1.38 2002/09/11 22:41:50 djm Exp $");
+RCSID("$OpenBSD: sftp-server.c,v 1.41 2003/03/26 04:02:51 deraadt Exp $");
 
 #include "buffer.h"
 #include "bufaux.h"
@@ -158,7 +158,7 @@ handle_new(int use, char *name, int fd, DIR *dirp)
                         handles[i].use = use;
                         handles[i].dirp = dirp;
                         handles[i].fd = fd;
-                        handles[i].name = name;
+                        handles[i].name = xstrdup(name);
                         return i;
                 }
         }
@@ -230,9 +230,11 @@ handle_close(int handle)
         if (handle_is_ok(handle, HANDLE_FILE)) {
                 ret = close(handles[handle].fd);
                 handles[handle].use = HANDLE_UNUSED;
+                xfree(handles[handle].name);
         } else if (handle_is_ok(handle, HANDLE_DIR)) {
                 ret = closedir(handles[handle].dirp);
                 handles[handle].use = HANDLE_UNUSED;
+                xfree(handles[handle].name);
         } else {
                 errno = ENOENT;
         }
@@ -396,7 +398,7 @@ process_open(void)
         if (fd < 0) {
                 status = errno_to_portable(errno);
         } else {
-                handle = handle_new(HANDLE_FILE, xstrdup(name), fd, NULL);
+                handle = handle_new(HANDLE_FILE, name, fd, NULL);
                 if (handle < 0) {
                         close(fd);
                 } else {
@@ -681,7 +683,7 @@ process_opendir(void)
         if (dirp == NULL) {
                 status = errno_to_portable(errno);
         } else {
-                handle = handle_new(HANDLE_DIR, xstrdup(path), 0, dirp);
+                handle = handle_new(HANDLE_DIR, path, 0, dirp);
                 if (handle < 0) {
                         closedir(dirp);
                 } else {
@@ -832,18 +834,32 @@ static void
 process_rename(void)
 {
         u_int32_t id;
-        struct stat st;
         char *oldpath, *newpath;
-        int ret, status = SSH2_FX_FAILURE;
+        int status;
+        struct stat sb;
 
         id = get_int();
         oldpath = get_string(NULL);
         newpath = get_string(NULL);
         TRACE("rename id %u old %s new %s", id, oldpath, newpath);
-        /* fail if 'newpath' exists */
-        if (stat(newpath, &st) == -1) {
-                ret = rename(oldpath, newpath);
-                status = (ret == -1) ? errno_to_portable(errno) : SSH2_FX_OK;
+        status = SSH2_FX_FAILURE;
+        if (lstat(oldpath, &sb) == -1)
+                status = errno_to_portable(errno);
+        else if (S_ISREG(sb.st_mode)) {
+                /* Race-free rename of regular files */
+                if (link(oldpath, newpath) == -1)
+                        status = errno_to_portable(errno);
+                else if (unlink(oldpath) == -1) {
+                        status = errno_to_portable(errno);
+                        /* clean spare link */
+                        unlink(newpath);
+                } else
+                        status = SSH2_FX_OK;
+        } else if (stat(newpath, &sb) == -1) {
+                if (rename(oldpath, newpath) == -1)
+                        status = errno_to_portable(errno);
+                else
+                        status = SSH2_FX_OK;
         }
         send_status(id, status);
         xfree(oldpath);
@@ -878,19 +894,16 @@ static void
 process_symlink(void)
 {
         u_int32_t id;
-        struct stat st;
         char *oldpath, *newpath;
-        int ret, status = SSH2_FX_FAILURE;
+        int ret, status;
 
         id = get_int();
         oldpath = get_string(NULL);
         newpath = get_string(NULL);
         TRACE("symlink id %u old %s new %s", id, oldpath, newpath);
-        /* fail if 'newpath' exists */
-        if (stat(newpath, &st) == -1) {
-                ret = symlink(oldpath, newpath);
-                status = (ret == -1) ? errno_to_portable(errno) : SSH2_FX_OK;
-        }
+        /* this will fail if 'newpath' exists */
+        ret = symlink(oldpath, newpath);
+        status = (ret == -1) ? errno_to_portable(errno) : SSH2_FX_OK;
         send_status(id, status);
         xfree(oldpath);
         xfree(newpath);