crypto: add a gcrypt cipher implementation

If we are linking to gnutls already and gnutls is built against
gcrypt, then we should use gcrypt as a cipher backend in
preference to our built-in backend.

This will be used when linking against GNUTLS 1.x and many
GNUTLS 2.x versions.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1435770638-25715-6-git-send-email-berrange@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Daniel P. Berrange 2015-07-01 18:10:33 +01:00 committed by Paolo Bonzini
parent ca38a4cc9e
commit 62893b67cd
4 changed files with 337 additions and 0 deletions

29
configure vendored
View File

@ -2126,6 +2126,7 @@ fi
##########################################
# GNUTLS probe
gnutls_gcrypt=no
if test "$gnutls" != "no"; then
if $pkg_config --exists "gnutls"; then
gnutls_cflags=`$pkg_config --cflags gnutls`
@ -2141,6 +2142,18 @@ if test "$gnutls" != "no"; then
else
gnutls_hash="no"
fi
if $pkg_config --exists 'gnutls >= 3.0'; then
gnutls_gcrypt=no
elif $pkg_config --exists 'gnutls >= 2.12'; then
case `$pkg_config --libs --static gnutls` in
*gcrypt*) gnutls_gcrypt=yes ;;
*nettle*) gnutls_gcrypt=no ;;
*) gnutls_gcrypt=yes ;;
esac
else
gnutls_gcrypt=yes
fi
elif test "$gnutls" = "yes"; then
feature_not_found "gnutls" "Install gnutls devel"
else
@ -2151,6 +2164,18 @@ else
gnutls_hash="no"
fi
if test "$gnutls_gcrypt" != "no"; then
if has "libgcrypt-config"; then
gcrypt_cflags=`libgcrypt-config --cflags`
gcrypt_libs=`libgcrypt-config --libs`
libs_softmmu="$gcrypt_libs $libs_softmmu"
libs_tools="$gcrypt_libs $libs_tools"
QEMU_CFLAGS="$QEMU_CFLAGS $gcrypt_cflags"
else
feature_not_found "gcrypt" "Install gcrypt devel"
fi
fi
##########################################
# VTE probe
@ -4463,6 +4488,7 @@ echo "SDL support $sdl"
echo "GTK support $gtk"
echo "GNUTLS support $gnutls"
echo "GNUTLS hash $gnutls_hash"
echo "GNUTLS gcrypt $gnutls_gcrypt"
echo "VTE support $vte"
echo "curses support $curses"
echo "curl support $curl"
@ -4827,6 +4853,9 @@ fi
if test "$gnutls_hash" = "yes" ; then
echo "CONFIG_GNUTLS_HASH=y" >> $config_host_mak
fi
if test "$gnutls_gcrypt" = "yes" ; then
echo "CONFIG_GNUTLS_GCRYPT=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

195
crypto/cipher-gcrypt.c Normal file
View File

@ -0,0 +1,195 @@
/*
* QEMU Crypto cipher libgcrypt algorithms
*
* Copyright (c) 2015 Red Hat, Inc.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, see <http://www.gnu.org/licenses/>.
*
*/
#include <gcrypt.h>
bool qcrypto_cipher_supports(QCryptoCipherAlgorithm alg)
{
switch (alg) {
case QCRYPTO_CIPHER_ALG_DES_RFB:
case QCRYPTO_CIPHER_ALG_AES_128:
case QCRYPTO_CIPHER_ALG_AES_192:
case QCRYPTO_CIPHER_ALG_AES_256:
return true;
default:
return false;
}
}
QCryptoCipher *qcrypto_cipher_new(QCryptoCipherAlgorithm alg,
QCryptoCipherMode mode,
const uint8_t *key, size_t nkey,
Error **errp)
{
QCryptoCipher *cipher;
gcry_cipher_hd_t handle;
gcry_error_t err;
int gcryalg, gcrymode;
switch (mode) {
case QCRYPTO_CIPHER_MODE_ECB:
gcrymode = GCRY_CIPHER_MODE_ECB;
break;
case QCRYPTO_CIPHER_MODE_CBC:
gcrymode = GCRY_CIPHER_MODE_CBC;
break;
default:
error_setg(errp, "Unsupported cipher mode %d", mode);
return NULL;
}
if (!qcrypto_cipher_validate_key_length(alg, nkey, errp)) {
return NULL;
}
switch (alg) {
case QCRYPTO_CIPHER_ALG_DES_RFB:
gcryalg = GCRY_CIPHER_DES;
break;
case QCRYPTO_CIPHER_ALG_AES_128:
gcryalg = GCRY_CIPHER_AES128;
break;
case QCRYPTO_CIPHER_ALG_AES_192:
gcryalg = GCRY_CIPHER_AES192;
break;
case QCRYPTO_CIPHER_ALG_AES_256:
gcryalg = GCRY_CIPHER_AES256;
break;
default:
error_setg(errp, "Unsupported cipher algorithm %d", alg);
return NULL;
}
cipher = g_new0(QCryptoCipher, 1);
cipher->alg = alg;
cipher->mode = mode;
err = gcry_cipher_open(&handle, gcryalg, gcrymode, 0);
if (err != 0) {
error_setg(errp, "Cannot initialize cipher: %s",
gcry_strerror(err));
goto error;
}
if (cipher->alg == QCRYPTO_CIPHER_ALG_DES_RFB) {
/* We're using standard DES cipher from gcrypt, so we need
* to munge the key so that the results are the same as the
* bizarre RFB variant of DES :-)
*/
uint8_t *rfbkey = qcrypto_cipher_munge_des_rfb_key(key, nkey);
err = gcry_cipher_setkey(handle, rfbkey, nkey);
g_free(rfbkey);
} else {
err = gcry_cipher_setkey(handle, key, nkey);
}
if (err != 0) {
error_setg(errp, "Cannot set key: %s",
gcry_strerror(err));
goto error;
}
cipher->opaque = handle;
return cipher;
error:
gcry_cipher_close(handle);
g_free(cipher);
return NULL;
}
void qcrypto_cipher_free(QCryptoCipher *cipher)
{
gcry_cipher_hd_t handle;
if (!cipher) {
return;
}
handle = cipher->opaque;
gcry_cipher_close(handle);
g_free(cipher);
}
int qcrypto_cipher_encrypt(QCryptoCipher *cipher,
const void *in,
void *out,
size_t len,
Error **errp)
{
gcry_cipher_hd_t handle = cipher->opaque;
gcry_error_t err;
err = gcry_cipher_encrypt(handle,
out, len,
in, len);
if (err != 0) {
error_setg(errp, "Cannot encrypt data: %s",
gcry_strerror(err));
return -1;
}
return 0;
}
int qcrypto_cipher_decrypt(QCryptoCipher *cipher,
const void *in,
void *out,
size_t len,
Error **errp)
{
gcry_cipher_hd_t handle = cipher->opaque;
gcry_error_t err;
err = gcry_cipher_decrypt(handle,
out, len,
in, len);
if (err != 0) {
error_setg(errp, "Cannot decrypt data: %s",
gcry_strerror(err));
return -1;
}
return 0;
}
int qcrypto_cipher_setiv(QCryptoCipher *cipher,
const uint8_t *iv, size_t niv,
Error **errp)
{
gcry_cipher_hd_t handle = cipher->opaque;
gcry_error_t err;
gcry_cipher_reset(handle);
err = gcry_cipher_setiv(handle, iv, niv);
if (err != 0) {
error_setg(errp, "Cannot set IV: %s",
gcry_strerror(err));
return -1;
}
return 0;
}

View File

@ -20,6 +20,7 @@
#include "crypto/cipher.h"
static size_t alg_key_len[QCRYPTO_CIPHER_ALG_LAST] = {
[QCRYPTO_CIPHER_ALG_AES_128] = 16,
[QCRYPTO_CIPHER_ALG_AES_192] = 24,
@ -46,4 +47,26 @@ qcrypto_cipher_validate_key_length(QCryptoCipherAlgorithm alg,
return true;
}
#if defined(CONFIG_GNUTLS_GCRYPT)
static uint8_t *
qcrypto_cipher_munge_des_rfb_key(const uint8_t *key,
size_t nkey)
{
uint8_t *ret = g_new0(uint8_t, nkey);
size_t i;
for (i = 0; i < nkey; i++) {
uint8_t r = key[i];
r = (r & 0xf0) >> 4 | (r & 0x0f) << 4;
r = (r & 0xcc) >> 2 | (r & 0x33) << 2;
r = (r & 0xaa) >> 1 | (r & 0x55) << 1;
ret[i] = r;
}
return ret;
}
#endif /* CONFIG_GNUTLS_GCRYPT */
#ifdef CONFIG_GNUTLS_GCRYPT
#include "crypto/cipher-gcrypt.c"
#else
#include "crypto/cipher-builtin.c"
#endif

View File

@ -19,13 +19,48 @@
*/
#include "crypto/init.h"
#include "qemu/thread.h"
#ifdef CONFIG_GNUTLS
#include <gnutls/gnutls.h>
#include <gnutls/crypto.h>
#ifdef CONFIG_GNUTLS_GCRYPT
#include <gcrypt.h>
#endif
/* #define DEBUG_GNUTLS */
/*
* If GNUTLS is built against GCrypt then
*
* - When GNUTLS >= 2.12, we must not initialize gcrypt threading
* because GNUTLS will do that itself
* - When GNUTLS < 2.12 we must always initialize gcrypt threading
*
* But....
*
* When gcrypt >= 1.6.0 we must not initialize gcrypt threading
* because gcrypt will do that itself.
*
* So we need to init gcrypt threading if
*
* - gcrypt < 1.6.0
* AND
* - gnutls < 2.12
*
*/
#if (defined(CONFIG_GNUTLS_GCRYPT) && \
(!defined(GNUTLS_VERSION_NUMBER) || \
(GNUTLS_VERSION_NUMBER < 0x020c00)) && \
(!defined(GCRYPT_VERSION_NUMBER) || \
(GCRYPT_VERSION_NUMBER < 0x010600)))
#define QCRYPTO_INIT_GCRYPT_THREADS
#else
#undef QCRYPTO_INIT_GCRYPT_THREADS
#endif
#ifdef DEBUG_GNUTLS
static void qcrypto_gnutls_log(int level, const char *str)
{
@ -33,6 +68,49 @@ static void qcrypto_gnutls_log(int level, const char *str)
}
#endif
#ifdef QCRYPTO_INIT_GCRYPT_THREADS
static int qcrypto_gcrypt_mutex_init(void **priv)
{ \
QemuMutex *lock = NULL;
lock = g_new0(QemuMutex, 1);
qemu_mutex_init(lock);
*priv = lock;
return 0;
}
static int qcrypto_gcrypt_mutex_destroy(void **priv)
{
QemuMutex *lock = *priv;
qemu_mutex_destroy(lock);
g_free(lock);
return 0;
}
static int qcrypto_gcrypt_mutex_lock(void **priv)
{
QemuMutex *lock = *priv;
qemu_mutex_lock(lock);
return 0;
}
static int qcrypto_gcrypt_mutex_unlock(void **priv)
{
QemuMutex *lock = *priv;
qemu_mutex_unlock(lock);
return 0;
}
static struct gcry_thread_cbs qcrypto_gcrypt_thread_impl = {
(GCRY_THREAD_OPTION_PTHREAD | (GCRY_THREAD_OPTION_VERSION << 8)),
NULL,
qcrypto_gcrypt_mutex_init,
qcrypto_gcrypt_mutex_destroy,
qcrypto_gcrypt_mutex_lock,
qcrypto_gcrypt_mutex_unlock,
NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL
};
#endif /* QCRYPTO_INIT_GCRYPT */
int qcrypto_init(Error **errp)
{
int ret;
@ -47,6 +125,18 @@ int qcrypto_init(Error **errp)
gnutls_global_set_log_level(10);
gnutls_global_set_log_function(qcrypto_gnutls_log);
#endif
#ifdef CONFIG_GNUTLS_GCRYPT
if (!gcry_check_version(GCRYPT_VERSION)) {
error_setg(errp, "Unable to initialize gcrypt");
return -1;
}
#ifdef QCRYPTO_INIT_GCRYPT_THREADS
gcry_control(GCRYCTL_SET_THREAD_CBS, &qcrypto_gcrypt_thread_impl);
#endif /* QCRYPTO_INIT_GCRYPT_THREADS */
gcry_control(GCRYCTL_INITIALIZATION_FINISHED, 0);
#endif
return 0;
}