[Qemu-devel] [PATCH v1 RFC 17/34] block: convert quorum blockdrv to use crypto APIs

["Daniel P. Berrange" <berrange@redhat.com>]

Get rid of direct use of gnutls APIs in quorum blockdrv in
favour of using the crypto APIs. This avoids the need to
do conditional compilation of the quorum driver. It can
simply report an error at file open file instead if the
required hash algorithm isn't supported by QEMU.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
---
 block/Makefile.objs |  2 +-
 block/quorum.c      | 38 +++++++++++++++++++-------------------
 configure           | 39 ---------------------------------------
 3 files changed, 20 insertions(+), 59 deletions(-)

diff --git a/block/Makefile.objs b/block/Makefile.objs
index db2933e..2b4210d 100644
--- a/block/Makefile.objs
+++ b/block/Makefile.objs
@@ -3,7 +3,7 @@ block-obj-y += qcow2.o qcow2-refcount.o qcow2-cluster.o qcow2-snapshot.o qcow2-c
 block-obj-y += qed.o qed-gencb.o qed-l2-cache.o qed-table.o qed-cluster.o
 block-obj-y += qed-check.o
 block-obj-$(CONFIG_VHDX) += vhdx.o vhdx-endian.o vhdx-log.o
-block-obj-$(CONFIG_QUORUM) += quorum.o
+block-obj-y += quorum.o
 block-obj-y += parallels.o blkdebug.o blkverify.o
 block-obj-y += block-backend.o snapshot.o qapi.o
 block-obj-$(CONFIG_WIN32) += raw-win32.o win32-aio.o
diff --git a/block/quorum.c b/block/quorum.c
index 437b122..86375b3 100644
--- a/block/quorum.c
+++ b/block/quorum.c
@@ -13,8 +13,6 @@
  * See the COPYING file in the top-level directory.
  */
 
-#include <gnutls/gnutls.h>
-#include <gnutls/crypto.h>
 #include "block/block_int.h"
 #include "qapi/qmp/qbool.h"
 #include "qapi/qmp/qdict.h"
@@ -23,6 +21,9 @@
 #include "qapi/qmp/qlist.h"
 #include "qapi/qmp/qstring.h"
 #include "qapi-event.h"
+#include "crypto/hash.h"
+
+#include <glib/gi18n.h>
 
 #define HASH_LENGTH 32
 
@@ -33,7 +34,7 @@
 
 /* This union holds a vote hash value */
 typedef union QuorumVoteValue {
-    char h[HASH_LENGTH];       /* SHA-256 hash */
+    uint8_t h[HASH_LENGTH];    /* SHA-256 hash */
     int64_t l;                 /* simpler 64 bits hash */
 } QuorumVoteValue;
 
@@ -430,25 +431,18 @@ static void quorum_free_vote_list(QuorumVotes *votes)
 
 static int quorum_compute_hash(QuorumAIOCB *acb, int i, QuorumVoteValue *hash)
 {
-    int j, ret;
-    gnutls_hash_hd_t dig;
     QEMUIOVector *qiov = &acb->qcrs[i].qiov;
-
-    ret = gnutls_hash_init(&dig, GNUTLS_DIG_SHA256);
-
-    if (ret < 0) {
-        return ret;
+    size_t len = sizeof(hash->h);
+    uint8_t *data = hash->h;
+
+    if (qcrypto_hash_bytesv(QCRYPTO_HASH_ALG_SHA256,
+                            qiov->iov, qiov->niov,
+                            &data, &len,
+                            NULL) < 0) {
+        return -EINVAL;
     }
 
-    for (j = 0; j < qiov->niov; j++) {
-        ret = gnutls_hash(dig, qiov->iov[j].iov_base, qiov->iov[j].iov_len);
-        if (ret < 0) {
-            break;
-        }
-    }
-
-    gnutls_hash_deinit(dig, (void *) hash);
-    return ret;
+    return 0;
 }
 
 static QuorumVoteVersion *quorum_get_vote_winner(QuorumVotes *votes)
@@ -875,6 +869,12 @@ static int quorum_open(BlockDriverState *bs, QDict *options, int flags,
     int i;
     int ret = 0;
 
+    if (!qcrypto_hash_supports(QCRYPTO_HASH_ALG_SHA256)) {
+        error_setg(errp, "%s",
+                   _("SHA256 hash support is required for quorum device"));
+        return -EINVAL;
+    }
+
     qdict_flatten(options);
     qdict_extract_subqdict(options, &sub, "children.");
     qdict_array_split(sub, &list);
diff --git a/configure b/configure
index f7ec73d..afca51e 100755
--- a/configure
+++ b/configure
@@ -336,7 +336,6 @@ vte=""
 tpm="yes"
 libssh2=""
 vhdx=""
-quorum=""
 numa=""
 
 # parse CC options first
@@ -1135,10 +1134,6 @@ for opt do
   ;;
   --disable-vhdx) vhdx="no"
   ;;
-  --disable-quorum) quorum="no"
-  ;;
-  --enable-quorum) quorum="yes"
-  ;;
   --disable-numa) numa="no"
   ;;
   --enable-numa) numa="yes"
@@ -1414,8 +1409,6 @@ Advanced options (experts only):
   --enable-libssh2         enable ssh block device support
   --disable-vhdx           disable support for the Microsoft VHDX image format
   --enable-vhdx            enable support for the Microsoft VHDX image format
-  --disable-quorum         disable quorum block filter support
-  --enable-quorum          enable quorum block filter support
   --disable-numa           disable libnuma support
   --enable-numa            enable libnuma support
 
@@ -2412,33 +2405,6 @@ EOF
 fi
 
 ##########################################
-# Quorum probe (check for gnutls)
-if test "$quorum" != "no" ; then
-cat > $TMPC <<EOF
-#include <gnutls/gnutls.h>
-#include <gnutls/crypto.h>
-int main(void) {char data[4096], digest[32];
-gnutls_hash_fast(GNUTLS_DIG_SHA256, data, 4096, digest);
-return 0;
-}
-EOF
-quorum_tls_cflags=`$pkg_config --cflags gnutls 2> /dev/null`
-quorum_tls_libs=`$pkg_config --libs gnutls 2> /dev/null`
-if compile_prog "$quorum_tls_cflags" "$quorum_tls_libs" ; then
-  qcow_tls=yes
-  libs_softmmu="$quorum_tls_libs $libs_softmmu"
-  libs_tools="$quorum_tls_libs $libs_softmmu"
-  QEMU_CFLAGS="$QEMU_CFLAGS $quorum_tls_cflags"
-  quorum="yes"
-else
-  if test "$quorum" = "yes"; then
-    feature_not_found "gnutls" "gnutls > 2.10.0 required to compile Quorum"
-  fi
-  quorum="no"
-fi
-fi
-
-##########################################
 # VNC SASL detection
 if test "$vnc" = "yes" -a "$vnc_sasl" != "no" ; then
   cat > $TMPC <<EOF
@@ -4545,7 +4511,6 @@ echo "libssh2 support   $libssh2"
 echo "TPM passthrough   $tpm_passthrough"
 echo "QOM debugging     $qom_cast_debug"
 echo "vhdx              $vhdx"
-echo "Quorum            $quorum"
 echo "lzo support       $lzo"
 echo "snappy support    $snappy"
 echo "bzip2 support     $bzip2"
@@ -5023,10 +4988,6 @@ if test "$libssh2" = "yes" ; then
   echo "LIBSSH2_LIBS=$libssh2_libs" >> $config_host_mak
 fi
 
-if test "$quorum" = "yes" ; then
-  echo "CONFIG_QUORUM=y" >> $config_host_mak
-fi
-
 if test "$vhdx" = "yes" ; then
   echo "CONFIG_VHDX=y" >> $config_host_mak
 fi
-- 
2.1.0