qcrypto-luks: don't overwrite cipher_mode in header

This way we can store the header we loaded, which
will be used in key management code

Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>

1 files changed, 6 insertions, 3 deletions

diff --git a/crypto/block-luks.c b/crypto/block-luks.c
index f12fa2d..25f8a9f 100644
--- a/crypto/block-luks.c
+++ b/crypto/block-luks.c
@@ -645,6 +645,7 @@ qcrypto_block_luks_open(QCryptoBlock *block,
     QCryptoHashAlgorithm hash;
     QCryptoHashAlgorithm ivhash;
     g_autofree char *password = NULL;
+    g_autofree char *cipher_mode = NULL;
 
     if (!(flags & QCRYPTO_BLOCK_OPEN_NO_IO)) {
         if (!options->u.luks.key_secret) {
@@ -701,6 +702,8 @@ qcrypto_block_luks_open(QCryptoBlock *block,
         goto fail;
     }
 
+    cipher_mode = g_strdup(luks->header.cipher_mode);
+
     /*
      * The cipher_mode header contains a string that we have
      * to further parse, of the format
@@ -709,11 +712,11 @@ qcrypto_block_luks_open(QCryptoBlock *block,
      *
      * eg  cbc-essiv:sha256, cbc-plain64
      */
-    ivgen_name = strchr(luks->header.cipher_mode, '-');
+    ivgen_name = strchr(cipher_mode, '-');
     if (!ivgen_name) {
         ret = -EINVAL;
         error_setg(errp, "Unexpected cipher mode string format %s",
-                   luks->header.cipher_mode);
+                   cipher_mode);
         goto fail;
     }
     *ivgen_name = '\0';
@@ -735,7 +738,7 @@ qcrypto_block_luks_open(QCryptoBlock *block,
         }
     }
 
-    ciphermode = qcrypto_block_luks_cipher_mode_lookup(luks->header.cipher_mode,
+    ciphermode = qcrypto_block_luks_cipher_mode_lookup(cipher_mode,
                                                        &local_err);
     if (local_err) {
         ret = -ENOTSUP;