From 788fb775f7deb8c456868362454e2a5f50c6068f Mon Sep 17 00:00:00 2001
From: Milan Broz <gmazyland@gmail.com>
Date: Mon, 27 May 2019 09:43:03 +0200
Subject: [PATCH] cryptsetup: call crypt_load() for LUKS only once

The crypt_load() for LUKS2 can read a quite big area of disk
(metadata area size is configurable and can increase up to megabytes).

This initialization is not needed to be repeated, just use the existing context.

(This patch is also required for the following change.)

(cherry picked from commit ea9a9d49e4af31c49e5c216e7e5e2f533e727579)

Related: #1719153
---
 src/cryptsetup/cryptsetup.c | 28 ++++++++++++----------------
 1 file changed, 12 insertions(+), 16 deletions(-)

diff --git a/src/cryptsetup/cryptsetup.c b/src/cryptsetup/cryptsetup.c
index 5be1469d69..a0bd80ea65 100644
--- a/src/cryptsetup/cryptsetup.c
+++ b/src/cryptsetup/cryptsetup.c
@@ -475,7 +475,6 @@ static int attach_tcrypt(
 static int attach_luks_or_plain(struct crypt_device *cd,
                                 const char *name,
                                 const char *key_file,
-                                const char *data_device,
                                 char **passwords,
                                 uint32_t flags) {
         int r = 0;
@@ -485,20 +484,6 @@ static int attach_luks_or_plain(struct crypt_device *cd,
         assert(name);
         assert(key_file || passwords);
 
-        if (!arg_type || STR_IN_SET(arg_type, ANY_LUKS, CRYPT_LUKS1)) {
-                r = crypt_load(cd, CRYPT_LUKS, NULL);
-                if (r < 0) {
-                        log_error("crypt_load() failed on device %s.\n", crypt_get_device_name(cd));
-                        return r;
-                }
-
-                if (data_device) {
-                        r = crypt_set_data_device(cd, data_device);
-                        if (r < 0)
-                                return log_error_errno(r, "Failed to set LUKS data device %s: %m", data_device);
-                }
-        }
-
         if ((!arg_type && !crypt_get_type(cd)) || streq_ptr(arg_type, CRYPT_PLAIN)) {
                 struct crypt_params_plain params = {
                         .offset = arg_offset,
@@ -687,6 +672,18 @@ int main(int argc, char *argv[]) {
                                 log_warning("Key file %s is world-readable. This is not a good idea!", key_file);
                 }
 
+                if (!arg_type || STR_IN_SET(arg_type, ANY_LUKS, CRYPT_LUKS1)) {
+                        r = crypt_load(cd, CRYPT_LUKS, NULL);
+                        if (r < 0)
+                                return log_error_errno(r, "Failed to load LUKS superblock on device %s: %m", crypt_get_device_name(cd));
+
+                        if (arg_header) {
+                                r = crypt_set_data_device(cd, argv[3]);
+                                if (r < 0)
+                                        return log_error_errno(r, "Failed to set LUKS data device %s: %m", argv[3]);
+                        }
+                }
+
                 for (tries = 0; arg_tries == 0 || tries < arg_tries; tries++) {
                         _cleanup_strv_free_erase_ char **passwords = NULL;
 
@@ -704,7 +701,6 @@ int main(int argc, char *argv[]) {
                                 r = attach_luks_or_plain(cd,
                                                          argv[2],
                                                          key_file,
-                                                         arg_header ? argv[3] : NULL,
                                                          passwords,
                                                          flags);
                         if (r >= 0)