Do not use stat for backup commands.

diff --git a/lib/luks1/keymanage.c b/lib/luks1/keymanage.c
index 025fcde..72d3f88 100644 (file)
--- a/lib/luks1/keymanage.c
+++ b/lib/luks1/keymanage.c
@@ -154,12 +154,6 @@ int LUKS_hdr_backup(
        int r = 0, devfd = -1;
        ssize_t buffer_size;
        char *buffer = NULL;
-       struct stat st;
-
-       if(stat(backup_file, &st) == 0) {
-               log_err(ctx, _("Requested file %s already exist.\n"), backup_file);
-               return -EINVAL;
-       }
 
        r = LUKS_read_phdr(hdr, 1, 0, ctx);
        if (r)
@@ -182,7 +176,7 @@ int LUKS_hdr_backup(
                goto out;
        }
 
-       if(read_blockwise(devfd, device_block_size(device), buffer, buffer_size) < buffer_size) {
+       if (read_blockwise(devfd, device_block_size(device), buffer, buffer_size) < buffer_size) {
                r = -EIO;
                goto out;
        }
@@ -192,12 +186,16 @@ int LUKS_hdr_backup(
        if (hdr->keyblock[0].keyMaterialOffset * SECTOR_SIZE == LUKS_ALIGN_KEYSLOTS)
                memset(buffer + sizeof(*hdr), 0, LUKS_ALIGN_KEYSLOTS - sizeof(*hdr));
 
-       devfd = creat(backup_file, S_IRUSR);
-       if(devfd == -1) {
+       devfd = open(backup_file, O_CREAT|O_EXCL|O_WRONLY, S_IRUSR);
+       if (devfd == -1) {
+               if (errno == EEXIST)
+                       log_err(ctx, _("Requested header backup file %s already exists.\n"), backup_file);
+               else
+                       log_err(ctx, _("Cannot create header backup file %s.\n"), backup_file);
                r = -EINVAL;
                goto out;
        }
-       if(write(devfd, buffer, buffer_size) < buffer_size) {
+       if (write(devfd, buffer, buffer_size) < buffer_size) {
                log_err(ctx, _("Cannot write header backup file %s.\n"), backup_file);
                r = -EIO;
                goto out;
@@ -221,15 +219,12 @@ int LUKS_hdr_restore(
        int r = 0, devfd = -1, diff_uuid = 0;
        ssize_t buffer_size = 0;
        char *buffer = NULL, msg[200];
-       struct stat st;
        struct luks_phdr hdr_file;
 
-       if(stat(backup_file, &st) < 0) {
-               log_err(ctx, _("Backup file %s doesn't exist.\n"), backup_file);
-               return -EINVAL;
-       }
-
        r = LUKS_read_phdr_backup(backup_file, &hdr_file, 0, ctx);
+       if (r == -ENOENT)
+               return r;
+
        if (!r)
                buffer_size = LUKS_device_sectors(hdr_file.keyBytes) << SECTOR_SHIFT;
 
@@ -246,13 +241,13 @@ int LUKS_hdr_restore(
        }
 
        devfd = open(backup_file, O_RDONLY);
-       if(devfd == -1) {
+       if (devfd == -1) {
                log_err(ctx, _("Cannot open header backup file %s.\n"), backup_file);
                r = -EINVAL;
                goto out;
        }
 
-       if(read(devfd, buffer, buffer_size) < buffer_size) {
+       if (read(devfd, buffer, buffer_size) < buffer_size) {
                log_err(ctx, _("Cannot read header backup file %s.\n"), backup_file);
                r = -EIO;
                goto out;
@@ -289,7 +284,7 @@ int LUKS_hdr_restore(
                sizeof(*hdr), buffer_size - LUKS_ALIGN_KEYSLOTS, device_path(device));
 
        devfd = open(device_path(device), O_WRONLY | O_DIRECT | O_SYNC);
-       if(devfd == -1) {
+       if (devfd == -1) {
                if (errno == EACCES)
                        log_err(ctx, _("Cannot write to device %s, permission denied.\n"),
                                device_path(device));
@@ -484,8 +479,8 @@ int LUKS_read_phdr_backup(const char *backup_file,
 
        devfd = open(backup_file, O_RDONLY);
        if(-1 == devfd) {
-               log_err(ctx, _("Cannot open file %s.\n"), backup_file);
-               return -EINVAL;
+               log_err(ctx, _("Cannot open header backup file %s.\n"), backup_file);
+               return -ENOENT;
        }
 
        if (read(devfd, hdr, hdr_size) < hdr_size)