Commit 62893b67 authored by Daniel P. Berrangé's avatar Daniel P. Berrangé Committed by Paolo Bonzini
Browse files

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: default avatarDaniel P. Berrange <berrange@redhat.com>
Message-Id: <1435770638-25715-6-git-send-email-berrange@redhat.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent ca38a4cc

configure

+29 −0
Original line number Diff line number Diff line
@@ -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

crypto/cipher-gcrypt.c

0 → 100644
+195 −0
Original line number Diff line number Diff line 
/*

 * 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;

}

crypto/cipher.c

+23 −0
Original line number Diff line number Diff line
@@ -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

crypto/init.c

+90 −0
Original line number Diff line number Diff line
@@ -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;

}