crypto: introduce new module for computing hash digests

Introduce a new crypto/ directory that will (eventually) contain
all the cryptographic related code. This initially defines a
wrapper for initializing gnutls and for computing hashes with
gnutls. The former ensures that gnutls is guaranteed to be
initialized exactly once in QEMU regardless of CLI args. The
block quorum code currently fails to initialize gnutls so it
only works by luck, if VNC server TLS is not requested. The
hash APIs avoids the need to litter the rest of the code with
preprocessor checks and simplifies callers by allocating the
correct amount of memory for the requested hash.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1435770638-25715-2-git-send-email-berrange@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

1 files changed, 45 insertions, 0 deletions

diff --git a/configure b/configure
index 3063739a5e..61a749edf3 100755
--- a/configure
+++ b/configure
@@ -330,6 +330,8 @@ glusterfs_zerofill="no"
 archipelago="no"
 gtk=""
 gtkabi=""
+gnutls=""
+gnutls_hash=""
 vte=""
 tpm="yes"
 libssh2=""
@@ -1118,6 +1120,10 @@ for opt do
   ;;
   --enable-gtk) gtk="yes"
   ;;
+  --disable-gnutls) gnutls="no"
+  ;;
+  --enable-gnutls) gnutls="yes"
+  ;;
   --enable-rdma) rdma="yes"
   ;;
   --disable-rdma) rdma="no"
@@ -1328,6 +1334,7 @@ disabled with --disable-FEATURE, default is enabled if available:
   debug-info      debugging information
   sparse          sparse checker
 
+  gnutls          GNUTLS cryptography support
   sdl             SDL UI
   --with-sdlabi     select preferred SDL ABI 1.2 or 2.0
   gtk             gtk UI
@@ -2115,6 +2122,36 @@ if test "$gtk" != "no"; then
     fi
 fi
 
+
+##########################################
+# GNUTLS probe
+
+if test "$gnutls" != "no"; then
+    if $pkg_config --exists "gnutls"; then
+        gnutls_cflags=`$pkg_config --cflags gnutls`
+        gnutls_libs=`$pkg_config --libs gnutls`
+        libs_softmmu="$gnutls_libs $libs_softmmu"
+        libs_tools="$gnutls_libs $libs_tools"
+	QEMU_CFLAGS="$QEMU_CFLAGS $gnutls_cflags"
+        gnutls="yes"
+
+	# gnutls_hash_init requires >= 2.9.10
+	if $pkg_config --exists "gnutls >= 2.9.10"; then
+            gnutls_hash="yes"
+	else
+	    gnutls_hash="no"
+	fi
+    elif test "$gnutls" = "yes"; then
+	feature_not_found "gnutls" "Install gnutls devel"
+    else
+        gnutls="no"
+        gnutls_hash="no"
+    fi
+else
+    gnutls_hash="no"
+fi
+
+
 ##########################################
 # VTE probe
 
@@ -4424,6 +4461,8 @@ fi
 echo "pixman            $pixman"
 echo "SDL support       $sdl"
 echo "GTK support       $gtk"
+echo "GNUTLS support    $gnutls"
+echo "GNUTLS hash       $gnutls_hash"
 echo "VTE support       $vte"
 echo "curses support    $curses"
 echo "curl support      $curl"
@@ -4782,6 +4821,12 @@ if test "$gtk" = "yes" ; then
   echo "CONFIG_GTKABI=$gtkabi" >> $config_host_mak
   echo "GTK_CFLAGS=$gtk_cflags" >> $config_host_mak
 fi
+if test "$gnutls" = "yes" ; then
+  echo "CONFIG_GNUTLS=y" >> $config_host_mak
+fi
+if test "$gnutls_hash" = "yes" ; then
+  echo "CONFIG_GNUTLS_HASH=y" >> $config_host_mak
+fi
 if test "$vte" = "yes" ; then
   echo "CONFIG_VTE=y" >> $config_host_mak
   echo "VTE_CFLAGS=$vte_cflags" >> $config_host_mak