[v2,09/13] qcrypto-block: extract check and parse header
diff mbox series

Message ID 20190826135103.22410-10-mlevitsk@redhat.com
State New
Headers show
Series
  • RFC crypto/luks: preparation for encryption key managment
Related show

Commit Message

Maxim Levitsky Aug. 26, 2019, 1:50 p.m. UTC
This is just to make qcrypto_block_luks_open more
reasonable in size.

Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
---
 crypto/block-luks.c | 254 +++++++++++++++++++++++++-------------------
 1 file changed, 146 insertions(+), 108 deletions(-)

Comments

Daniel P. Berrangé Sept. 6, 2019, 1:11 p.m. UTC | #1
On Mon, Aug 26, 2019 at 04:50:59PM +0300, Maxim Levitsky wrote:
> This is just to make qcrypto_block_luks_open more
> reasonable in size.
> 
> Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
> ---
>  crypto/block-luks.c | 254 +++++++++++++++++++++++++-------------------
>  1 file changed, 146 insertions(+), 108 deletions(-)
> 
> diff --git a/crypto/block-luks.c b/crypto/block-luks.c
> index b4dc6fc899..cc9a52c9af 100644
> --- a/crypto/block-luks.c
> +++ b/crypto/block-luks.c
> @@ -508,6 +508,148 @@ fail:
>      return ret;
>  }
>  
> +/*
> + * Does basic sanity checks on the LUKS header
> + */
> +static int
> +qcrypto_block_luks_check_header(const QCryptoBlockLUKS *luks, Error **errp)
> +{
> +    int ret;
> +
> +    if (memcmp(luks->header.magic, qcrypto_block_luks_magic,
> +               QCRYPTO_BLOCK_LUKS_MAGIC_LEN) != 0) {
> +        error_setg(errp, "Volume is not in LUKS format");
> +        ret = -EINVAL;
> +        goto fail;
> +    }

Just 'return -1' here immediately - don't return an errno, as we're
using Error objects for reporting.

> +
> +    if (luks->header.version != QCRYPTO_BLOCK_LUKS_VERSION) {
> +        error_setg(errp, "LUKS version %" PRIu32 " is not supported",
> +                   luks->header.version);
> +        ret = -ENOTSUP;
> +        goto fail;
> +    }
> +
> +    return 0;
> +fail:
> +    return ret;
> +}
> +
> +/*
> + * Parses the crypto parameters that are stored in the LUKS header
> + */
> +
> +static int
> +qcrypto_block_luks_parse_header(QCryptoBlockLUKS *luks, Error **errp)
> +{
> +    g_autofree char *cipher_mode = g_strdup(luks->header.cipher_mode);
> +    char *ivgen_name, *ivhash_name;
> +    int ret = -1;
> +    Error *local_err = NULL;
> +
> +    /*
> +     * The cipher_mode header contains a string that we have
> +     * to further parse, of the format
> +     *
> +     *    <cipher-mode>-<iv-generator>[:<iv-hash>]
> +     *
> +     * eg  cbc-essiv:sha256, cbc-plain64
> +     */
> +    ivgen_name = strchr(cipher_mode, '-');
> +    if (!ivgen_name) {
> +        ret = -EINVAL;

Again, don't use errnos - just return -1 in this method.

> +        error_setg(errp, "Unexpected cipher mode string format %s",
> +                   luks->header.cipher_mode);
> +        goto out;
> +    }
> +    *ivgen_name = '\0';
> +    ivgen_name++;
> +
> +    ivhash_name = strchr(ivgen_name, ':');
> +    if (!ivhash_name) {
> +        luks->ivgen_hash_alg = 0;
> +    } else {
> +        *ivhash_name = '\0';
> +        ivhash_name++;
> +
> +        luks->ivgen_hash_alg = qcrypto_block_luks_hash_name_lookup(ivhash_name,
> +                                                                   &local_err);
> +        if (local_err) {
> +            ret = -ENOTSUP;
> +            error_propagate(errp, local_err);
> +            goto out;
> +        }
> +    }
> +
> +    luks->cipher_mode = qcrypto_block_luks_cipher_mode_lookup(cipher_mode,
> +                                                              &local_err);
> +    if (local_err) {
> +        ret = -ENOTSUP;
> +        error_propagate(errp, local_err);
> +        goto out;
> +    }
> +
> +    luks->cipher_alg =
> +            qcrypto_block_luks_cipher_name_lookup(luks->header.cipher_name,
> +                                                  luks->cipher_mode,
> +                                                  luks->header.master_key_len,
> +                                                  &local_err);
> +    if (local_err) {
> +        ret = -ENOTSUP;
> +        error_propagate(errp, local_err);
> +        goto out;
> +    }
> +
> +    luks->hash_alg =
> +            qcrypto_block_luks_hash_name_lookup(luks->header.hash_spec,
> +                                               &local_err);
> +    if (local_err) {
> +        ret = -ENOTSUP;
> +        error_propagate(errp, local_err);
> +        goto out;
> +    }
> +
> +    luks->ivgen_alg = qcrypto_block_luks_ivgen_name_lookup(ivgen_name,
> +                                                           &local_err);
> +    if (local_err) {
> +        ret = -ENOTSUP;
> +        error_propagate(errp, local_err);
> +        goto out;
> +    }
> +
> +    if (luks->ivgen_alg == QCRYPTO_IVGEN_ALG_ESSIV) {
> +        if (!ivhash_name) {
> +            ret = -EINVAL;
> +            error_setg(errp, "Missing IV generator hash specification");
> +            goto out;
> +        }
> +        luks->ivgen_cipher_alg =
> +                qcrypto_block_luks_essiv_cipher(luks->cipher_alg,
> +                                                luks->ivgen_hash_alg,
> +                                                &local_err);
> +        if (local_err) {
> +            ret = -ENOTSUP;
> +            error_propagate(errp, local_err);
> +            goto out;
> +        }
> +    } else {
> +
> +        /*
> +         * Note we parsed the ivhash_name earlier in the cipher_mode
> +         * spec string even with plain/plain64 ivgens, but we
> +         * will ignore it, since it is irrelevant for these ivgens.
> +         * This is for compat with dm-crypt which will silently
> +         * ignore hash names with these ivgens rather than report
> +         * an error about the invalid usage
> +         */
> +        luks->ivgen_cipher_alg = luks->cipher_alg;
> +    }
> +    ret = 0;
> +out:
> +    return ret;
> +
> +}
> +
>  /*
>   * Given a key slot, and user password, this will attempt to unlock
>   * the master encryption key from the key slot.
> @@ -720,12 +862,9 @@ qcrypto_block_luks_open(QCryptoBlock *block,
>                          Error **errp)
>  {
>      QCryptoBlockLUKS *luks = NULL;
> -    Error *local_err = NULL;
>      int ret = 0;
>      g_autofree uint8_t *masterkey = NULL;
> -    char *ivgen_name, *ivhash_name;
>      g_autofree char *password = NULL;
> -    g_autofree char *cipher_mode = NULL;
>  
>      if (!(flags & QCRYPTO_BLOCK_OPEN_NO_IO)) {
>          if (!options->u.luks.key_secret) {
> @@ -748,117 +887,16 @@ qcrypto_block_luks_open(QCryptoBlock *block,
>          goto fail;
>      }
>  
> -
> -    if (memcmp(luks->header.magic, qcrypto_block_luks_magic,
> -               QCRYPTO_BLOCK_LUKS_MAGIC_LEN) != 0) {
> -        error_setg(errp, "Volume is not in LUKS format");
> -        ret = -EINVAL;

I can't remember why I set ret to an errno in my original code.
it is entirely pointless, as the caller of this method merely
checks "ret < 0" and doesn't do anything else with the return
value. IOW, we should just purge the errnors from this existing
code entirely.


Regards,
Daniel
Maxim Levitsky Sept. 12, 2019, 7:24 a.m. UTC | #2
On Fri, 2019-09-06 at 14:11 +0100, Daniel P. Berrangé wrote:
> On Mon, Aug 26, 2019 at 04:50:59PM +0300, Maxim Levitsky wrote:
> > This is just to make qcrypto_block_luks_open more
> > reasonable in size.
> > 
> > Signed-off-by: Maxim Levitsky <mlevitsk@redhat.com>
> > ---
> >  crypto/block-luks.c | 254 +++++++++++++++++++++++++-------------------
> >  1 file changed, 146 insertions(+), 108 deletions(-)
> > 
> > diff --git a/crypto/block-luks.c b/crypto/block-luks.c
> > index b4dc6fc899..cc9a52c9af 100644
> > --- a/crypto/block-luks.c
> > +++ b/crypto/block-luks.c
> > @@ -508,6 +508,148 @@ fail:
> >      return ret;
> >  }
> >  
> > +/*
> > + * Does basic sanity checks on the LUKS header
> > + */
> > +static int
> > +qcrypto_block_luks_check_header(const QCryptoBlockLUKS *luks, Error **errp)
> > +{
> > +    int ret;
> > +
> > +    if (memcmp(luks->header.magic, qcrypto_block_luks_magic,
> > +               QCRYPTO_BLOCK_LUKS_MAGIC_LEN) != 0) {
> > +        error_setg(errp, "Volume is not in LUKS format");
> > +        ret = -EINVAL;
> > +        goto fail;
> > +    }
> 
> Just 'return -1' here immediately - don't return an errno, as we're
> using Error objects for reporting.
> 
> > +
> > +    if (luks->header.version != QCRYPTO_BLOCK_LUKS_VERSION) {
> > +        error_setg(errp, "LUKS version %" PRIu32 " is not supported",
> > +                   luks->header.version);
> > +        ret = -ENOTSUP;
> > +        goto fail;
> > +    }
> > +
> > +    return 0;
> > +fail:
> > +    return ret;
> > +}
> > +
> > +/*
> > + * Parses the crypto parameters that are stored in the LUKS header
> > + */
> > +
> > +static int
> > +qcrypto_block_luks_parse_header(QCryptoBlockLUKS *luks, Error **errp)
> > +{
> > +    g_autofree char *cipher_mode = g_strdup(luks->header.cipher_mode);
> > +    char *ivgen_name, *ivhash_name;
> > +    int ret = -1;
> > +    Error *local_err = NULL;
> > +
> > +    /*
> > +     * The cipher_mode header contains a string that we have
> > +     * to further parse, of the format
> > +     *
> > +     *    <cipher-mode>-<iv-generator>[:<iv-hash>]
> > +     *
> > +     * eg  cbc-essiv:sha256, cbc-plain64
> > +     */
> > +    ivgen_name = strchr(cipher_mode, '-');
> > +    if (!ivgen_name) {
> > +        ret = -EINVAL;
> 
> Again, don't use errnos - just return -1 in this method.
> 
> > +        error_setg(errp, "Unexpected cipher mode string format %s",
> > +                   luks->header.cipher_mode);
> > +        goto out;
> > +    }
> > +    *ivgen_name = '\0';
> > +    ivgen_name++;
> > +
> > +    ivhash_name = strchr(ivgen_name, ':');
> > +    if (!ivhash_name) {
> > +        luks->ivgen_hash_alg = 0;
> > +    } else {
> > +        *ivhash_name = '\0';
> > +        ivhash_name++;
> > +
> > +        luks->ivgen_hash_alg = qcrypto_block_luks_hash_name_lookup(ivhash_name,
> > +                                                                   &local_err);
> > +        if (local_err) {
> > +            ret = -ENOTSUP;
> > +            error_propagate(errp, local_err);
> > +            goto out;
> > +        }
> > +    }
> > +
> > +    luks->cipher_mode = qcrypto_block_luks_cipher_mode_lookup(cipher_mode,
> > +                                                              &local_err);
> > +    if (local_err) {
> > +        ret = -ENOTSUP;
> > +        error_propagate(errp, local_err);
> > +        goto out;
> > +    }
> > +
> > +    luks->cipher_alg =
> > +            qcrypto_block_luks_cipher_name_lookup(luks->header.cipher_name,
> > +                                                  luks->cipher_mode,
> > +                                                  luks->header.master_key_len,
> > +                                                  &local_err);
> > +    if (local_err) {
> > +        ret = -ENOTSUP;
> > +        error_propagate(errp, local_err);
> > +        goto out;
> > +    }
> > +
> > +    luks->hash_alg =
> > +            qcrypto_block_luks_hash_name_lookup(luks->header.hash_spec,
> > +                                               &local_err);
> > +    if (local_err) {
> > +        ret = -ENOTSUP;
> > +        error_propagate(errp, local_err);
> > +        goto out;
> > +    }
> > +
> > +    luks->ivgen_alg = qcrypto_block_luks_ivgen_name_lookup(ivgen_name,
> > +                                                           &local_err);
> > +    if (local_err) {
> > +        ret = -ENOTSUP;
> > +        error_propagate(errp, local_err);
> > +        goto out;
> > +    }
> > +
> > +    if (luks->ivgen_alg == QCRYPTO_IVGEN_ALG_ESSIV) {
> > +        if (!ivhash_name) {
> > +            ret = -EINVAL;
> > +            error_setg(errp, "Missing IV generator hash specification");
> > +            goto out;
> > +        }
> > +        luks->ivgen_cipher_alg =
> > +                qcrypto_block_luks_essiv_cipher(luks->cipher_alg,
> > +                                                luks->ivgen_hash_alg,
> > +                                                &local_err);
> > +        if (local_err) {
> > +            ret = -ENOTSUP;
> > +            error_propagate(errp, local_err);
> > +            goto out;
> > +        }
> > +    } else {
> > +
> > +        /*
> > +         * Note we parsed the ivhash_name earlier in the cipher_mode
> > +         * spec string even with plain/plain64 ivgens, but we
> > +         * will ignore it, since it is irrelevant for these ivgens.
> > +         * This is for compat with dm-crypt which will silently
> > +         * ignore hash names with these ivgens rather than report
> > +         * an error about the invalid usage
> > +         */
> > +        luks->ivgen_cipher_alg = luks->cipher_alg;
> > +    }
> > +    ret = 0;
> > +out:
> > +    return ret;
> > +
> > +}
> > +
> >  /*
> >   * Given a key slot, and user password, this will attempt to unlock
> >   * the master encryption key from the key slot.
> > @@ -720,12 +862,9 @@ qcrypto_block_luks_open(QCryptoBlock *block,
> >                          Error **errp)
> >  {
> >      QCryptoBlockLUKS *luks = NULL;
> > -    Error *local_err = NULL;
> >      int ret = 0;
> >      g_autofree uint8_t *masterkey = NULL;
> > -    char *ivgen_name, *ivhash_name;
> >      g_autofree char *password = NULL;
> > -    g_autofree char *cipher_mode = NULL;
> >  
> >      if (!(flags & QCRYPTO_BLOCK_OPEN_NO_IO)) {
> >          if (!options->u.luks.key_secret) {
> > @@ -748,117 +887,16 @@ qcrypto_block_luks_open(QCryptoBlock *block,
> >          goto fail;
> >      }
> >  
> > -
> > -    if (memcmp(luks->header.magic, qcrypto_block_luks_magic,
> > -               QCRYPTO_BLOCK_LUKS_MAGIC_LEN) != 0) {
> > -        error_setg(errp, "Volume is not in LUKS format");
> > -        ret = -EINVAL;
> 
> I can't remember why I set ret to an errno in my original code.
> it is entirely pointless, as the caller of this method merely
> checks "ret < 0" and doesn't do anything else with the return
> value. IOW, we should just purge the errnors from this existing
> code entirely.

Nothing against that, I'll do that in a separate patch now.
Best regards,
	Maxim Levitsky

Patch
diff mbox series

diff --git a/crypto/block-luks.c b/crypto/block-luks.c
index b4dc6fc899..cc9a52c9af 100644
--- a/crypto/block-luks.c
+++ b/crypto/block-luks.c
@@ -508,6 +508,148 @@  fail:
     return ret;
 }
 
+/*
+ * Does basic sanity checks on the LUKS header
+ */
+static int
+qcrypto_block_luks_check_header(const QCryptoBlockLUKS *luks, Error **errp)
+{
+    int ret;
+
+    if (memcmp(luks->header.magic, qcrypto_block_luks_magic,
+               QCRYPTO_BLOCK_LUKS_MAGIC_LEN) != 0) {
+        error_setg(errp, "Volume is not in LUKS format");
+        ret = -EINVAL;
+        goto fail;
+    }
+
+    if (luks->header.version != QCRYPTO_BLOCK_LUKS_VERSION) {
+        error_setg(errp, "LUKS version %" PRIu32 " is not supported",
+                   luks->header.version);
+        ret = -ENOTSUP;
+        goto fail;
+    }
+
+    return 0;
+fail:
+    return ret;
+}
+
+/*
+ * Parses the crypto parameters that are stored in the LUKS header
+ */
+
+static int
+qcrypto_block_luks_parse_header(QCryptoBlockLUKS *luks, Error **errp)
+{
+    g_autofree char *cipher_mode = g_strdup(luks->header.cipher_mode);
+    char *ivgen_name, *ivhash_name;
+    int ret = -1;
+    Error *local_err = NULL;
+
+    /*
+     * The cipher_mode header contains a string that we have
+     * to further parse, of the format
+     *
+     *    <cipher-mode>-<iv-generator>[:<iv-hash>]
+     *
+     * eg  cbc-essiv:sha256, cbc-plain64
+     */
+    ivgen_name = strchr(cipher_mode, '-');
+    if (!ivgen_name) {
+        ret = -EINVAL;
+        error_setg(errp, "Unexpected cipher mode string format %s",
+                   luks->header.cipher_mode);
+        goto out;
+    }
+    *ivgen_name = '\0';
+    ivgen_name++;
+
+    ivhash_name = strchr(ivgen_name, ':');
+    if (!ivhash_name) {
+        luks->ivgen_hash_alg = 0;
+    } else {
+        *ivhash_name = '\0';
+        ivhash_name++;
+
+        luks->ivgen_hash_alg = qcrypto_block_luks_hash_name_lookup(ivhash_name,
+                                                                   &local_err);
+        if (local_err) {
+            ret = -ENOTSUP;
+            error_propagate(errp, local_err);
+            goto out;
+        }
+    }
+
+    luks->cipher_mode = qcrypto_block_luks_cipher_mode_lookup(cipher_mode,
+                                                              &local_err);
+    if (local_err) {
+        ret = -ENOTSUP;
+        error_propagate(errp, local_err);
+        goto out;
+    }
+
+    luks->cipher_alg =
+            qcrypto_block_luks_cipher_name_lookup(luks->header.cipher_name,
+                                                  luks->cipher_mode,
+                                                  luks->header.master_key_len,
+                                                  &local_err);
+    if (local_err) {
+        ret = -ENOTSUP;
+        error_propagate(errp, local_err);
+        goto out;
+    }
+
+    luks->hash_alg =
+            qcrypto_block_luks_hash_name_lookup(luks->header.hash_spec,
+                                               &local_err);
+    if (local_err) {
+        ret = -ENOTSUP;
+        error_propagate(errp, local_err);
+        goto out;
+    }
+
+    luks->ivgen_alg = qcrypto_block_luks_ivgen_name_lookup(ivgen_name,
+                                                           &local_err);
+    if (local_err) {
+        ret = -ENOTSUP;
+        error_propagate(errp, local_err);
+        goto out;
+    }
+
+    if (luks->ivgen_alg == QCRYPTO_IVGEN_ALG_ESSIV) {
+        if (!ivhash_name) {
+            ret = -EINVAL;
+            error_setg(errp, "Missing IV generator hash specification");
+            goto out;
+        }
+        luks->ivgen_cipher_alg =
+                qcrypto_block_luks_essiv_cipher(luks->cipher_alg,
+                                                luks->ivgen_hash_alg,
+                                                &local_err);
+        if (local_err) {
+            ret = -ENOTSUP;
+            error_propagate(errp, local_err);
+            goto out;
+        }
+    } else {
+
+        /*
+         * Note we parsed the ivhash_name earlier in the cipher_mode
+         * spec string even with plain/plain64 ivgens, but we
+         * will ignore it, since it is irrelevant for these ivgens.
+         * This is for compat with dm-crypt which will silently
+         * ignore hash names with these ivgens rather than report
+         * an error about the invalid usage
+         */
+        luks->ivgen_cipher_alg = luks->cipher_alg;
+    }
+    ret = 0;
+out:
+    return ret;
+
+}
+
 /*
  * Given a key slot, and user password, this will attempt to unlock
  * the master encryption key from the key slot.
@@ -720,12 +862,9 @@  qcrypto_block_luks_open(QCryptoBlock *block,
                         Error **errp)
 {
     QCryptoBlockLUKS *luks = NULL;
-    Error *local_err = NULL;
     int ret = 0;
     g_autofree uint8_t *masterkey = NULL;
-    char *ivgen_name, *ivhash_name;
     g_autofree char *password = NULL;
-    g_autofree char *cipher_mode = NULL;
 
     if (!(flags & QCRYPTO_BLOCK_OPEN_NO_IO)) {
         if (!options->u.luks.key_secret) {
@@ -748,117 +887,16 @@  qcrypto_block_luks_open(QCryptoBlock *block,
         goto fail;
     }
 
-
-    if (memcmp(luks->header.magic, qcrypto_block_luks_magic,
-               QCRYPTO_BLOCK_LUKS_MAGIC_LEN) != 0) {
-        error_setg(errp, "Volume is not in LUKS format");
-        ret = -EINVAL;
-        goto fail;
-    }
-    if (luks->header.version != QCRYPTO_BLOCK_LUKS_VERSION) {
-        error_setg(errp, "LUKS version %" PRIu32 " is not supported",
-                   luks->header.version);
-        ret = -ENOTSUP;
-        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
-     *
-     *    <cipher-mode>-<iv-generator>[:<iv-hash>]
-     *
-     * eg  cbc-essiv:sha256, cbc-plain64
-     */
-    ivgen_name = strchr(cipher_mode, '-');
-    if (!ivgen_name) {
-        ret = -EINVAL;
-        error_setg(errp, "Unexpected cipher mode string format %s",
-                cipher_mode);
-        goto fail;
-    }
-    *ivgen_name = '\0';
-    ivgen_name++;
-
-    ivhash_name = strchr(ivgen_name, ':');
-    if (!ivhash_name) {
-        luks->ivgen_hash_alg = 0;
-    } else {
-        *ivhash_name = '\0';
-        ivhash_name++;
-
-        luks->ivgen_hash_alg = qcrypto_block_luks_hash_name_lookup(ivhash_name,
-                                                                   &local_err);
-        if (local_err) {
-            ret = -ENOTSUP;
-            error_propagate(errp, local_err);
-            goto fail;
-        }
-    }
-
-    luks->cipher_mode = qcrypto_block_luks_cipher_mode_lookup(cipher_mode,
-                                                              &local_err);
-    if (local_err) {
-        ret = -ENOTSUP;
-        error_propagate(errp, local_err);
-        goto fail;
-    }
-
-    luks->cipher_alg =
-        qcrypto_block_luks_cipher_name_lookup(luks->header.cipher_name,
-                                              luks->cipher_mode,
-                                              luks->header.master_key_len,
-                                              &local_err);
-    if (local_err) {
-        ret = -ENOTSUP;
-        error_propagate(errp, local_err);
-        goto fail;
-    }
-
-    luks->hash_alg =
-            qcrypto_block_luks_hash_name_lookup(luks->header.hash_spec,
-                                                &local_err);
-    if (local_err) {
-        ret = -ENOTSUP;
-        error_propagate(errp, local_err);
+    ret = qcrypto_block_luks_check_header(luks, errp);
+    if (ret) {
         goto fail;
     }
 
-    luks->ivgen_alg = qcrypto_block_luks_ivgen_name_lookup(ivgen_name,
-                                                           &local_err);
-    if (local_err) {
-        ret = -ENOTSUP;
-        error_propagate(errp, local_err);
+    ret = qcrypto_block_luks_parse_header(luks, errp);
+    if (ret) {
         goto fail;
     }
 
-    if (luks->ivgen_alg == QCRYPTO_IVGEN_ALG_ESSIV) {
-        if (!ivhash_name) {
-            ret = -EINVAL;
-            error_setg(errp, "Missing IV generator hash specification");
-            goto fail;
-        }
-        luks->ivgen_cipher_alg =
-                qcrypto_block_luks_essiv_cipher(luks->cipher_alg,
-                                                luks->ivgen_hash_alg,
-                                                &local_err);
-        if (local_err) {
-            ret = -ENOTSUP;
-            error_propagate(errp, local_err);
-            goto fail;
-        }
-    } else {
-        /* Note we parsed the ivhash_name earlier in the cipher_mode
-         * spec string even with plain/plain64 ivgens, but we
-         * will ignore it, since it is irrelevant for these ivgens.
-         * This is for compat with dm-crypt which will silently
-         * ignore hash names with these ivgens rather than report
-         * an error about the invalid usage
-         */
-        luks->ivgen_cipher_alg = luks->cipher_alg;
-    }
 
     if (!(flags & QCRYPTO_BLOCK_OPEN_NO_IO)) {
         /* Try to find which key slot our password is valid for