[Qemu-devel] [RFC V5 08/62] qcow2: Implement qcow2_compute_cluster_hash.

["Benoît Canet" <benoit@irqsave.net>]

Add detection of libgnutls used to compute SHA256 hashes

Signed-off-by: Benoit Canet <benoit@irqsave.net>
---
 block/qcow2-dedup.c |   13 ++++++++++++-
 configure           |   22 ++++++++++++++++++++++
 2 files changed, 34 insertions(+), 1 deletion(-)

diff --git a/block/qcow2-dedup.c b/block/qcow2-dedup.c
index a424af8..45b2326 100644
--- a/block/qcow2-dedup.c
+++ b/block/qcow2-dedup.c
@@ -25,6 +25,8 @@
  * THE SOFTWARE.
  */
 
+#include <gnutls/gnutls.h>
+#include <gnutls/crypto.h>
 #include "block/block_int.h"
 #include "qemu-common.h"
 #include "qcow2.h"
@@ -157,7 +159,16 @@ static int qcow2_compute_cluster_hash(BlockDriverState *bs,
                                        QCowHash *hash,
                                        uint8_t *data)
 {
-    return 0;
+    BDRVQcowState *s = bs->opaque;
+    switch (s->dedup_hash_algo) {
+    case QCOW_HASH_SHA256:
+        return gnutls_hash_fast(GNUTLS_DIG_SHA256, data,
+                                s->cluster_size, hash->data);
+    default:
+        error_report("Invalid deduplication hash algorithm %i",
+                     s->dedup_hash_algo);
+        abort();
+    }
 }
 
 /*
diff --git a/configure b/configure
index 99c1ec3..390326e 100755
--- a/configure
+++ b/configure
@@ -1724,6 +1724,28 @@ EOF
 fi
 
 ##########################################
+# QCOW Deduplication gnutls detection
+cat > $TMPC <<EOF
+#include <gnutls/gnutls.h>
+#include <gnutls/crypto.h>
+int main(void) {char data[4096], digest[32];
+gnutls_hash_fast(GNUTLS_DIG_SHA256, data, 4096, digest);
+return 0;
+}
+EOF
+qcow_tls_cflags=`$pkg_config --cflags gnutls 2> /dev/null`
+qcow_tls_libs=`$pkg_config --libs gnutls 2> /dev/null`
+if compile_prog "$qcow_tls_cflags" "$qcow_tls_libs" ; then
+  qcow_tls=yes
+  libs_softmmu="$qcow_tls_libs $libs_softmmu"
+  libs_tools="$qcow_tls_libs $libs_softmmu"
+  QEMU_CFLAGS="$QEMU_CFLAGS $qcow_tls_cflags"
+else
+  echo "gnutls > 2.10.0 required to compile QEMU"
+  exit 1
+fi
+
+##########################################
 # VNC SASL detection
 if test "$vnc" = "yes" -a "$vnc_sasl" != "no" ; then
   cat > $TMPC <<EOF
-- 
1.7.10.4