diff mbox

[v2,04/10] crypto: introduce generic cipher API & built-in implementation

Message ID 1433252721-19610-5-git-send-email-berrange@redhat.com
State New
Headers show

Commit Message

Daniel P. Berrangé June 2, 2015, 1:45 p.m. UTC
Introduce a generic cipher API and an implementation of it that
supports only the built-in AES and DES-RFB algorithms.

The test suite checks the supported algorithms + modes to
validate that every backend implementation is actually correctly
complying with the specs.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
---
 crypto/Makefile.objs       |   1 +
 crypto/cipher-builtin.c    | 400 +++++++++++++++++++++++++++++++++++++++++++++
 crypto/cipher.c            |  50 ++++++
 include/crypto/cipher.h    | 210 ++++++++++++++++++++++++
 tests/.gitignore           |   1 +
 tests/Makefile             |   2 +
 tests/test-crypto-cipher.c | 290 ++++++++++++++++++++++++++++++++
 7 files changed, 954 insertions(+)
 create mode 100644 crypto/cipher-builtin.c
 create mode 100644 crypto/cipher.c
 create mode 100644 include/crypto/cipher.h
 create mode 100644 tests/test-crypto-cipher.c

Comments

Gonglei (Arei) June 8, 2015, 9:14 a.m. UTC | #1
On 2015/6/2 21:45, Daniel P. Berrange wrote:
> +
> +static int qcrypto_cipher_encrypt_des_rfb(QCryptoCipher *cipher,
> +                                          const void *in,
> +                                          void *out,
> +                                          size_t len,
> +                                          Error **errp)
> +{
> +    QCryptoCipherBuiltin *ctxt = cipher->opaque;
> +    size_t i;
> +
> +    deskey(ctxt->state.desrfb.key, EN0);
> +
Why not move the below check to top of deskey() ? and...

> +    if (len % 8) {
> +        error_setg(errp, _("Buffer size must be multiple of 8 not %zu"),
> +                   len);
> +        return -1;
> +    }
> +
> +    for (i = 0; i < len; i += 8) {
> +        des((void *)in + i, out + i);
> +    }
> +
> +    return 0;
> +}
> +
> +
> +static int qcrypto_cipher_decrypt_des_rfb(QCryptoCipher *cipher,
> +                                          const void *in,
> +                                          void *out,
> +                                          size_t len,
> +                                          Error **errp)
> +{
> +    QCryptoCipherBuiltin *ctxt = cipher->opaque;
> +    size_t i;
> +
> +    deskey(ctxt->state.desrfb.key, DE1);
> +

...the same.

> +    if (len % 8) {
> +        error_setg(errp, _("Buffer size must be multiple of 8 not %zu"),
> +                   len);
> +        return -1;
> +    }
> +
> +    for (i = 0; i < len; i += 8) {
> +        des((void *)in + i, out + i);
> +    }
> +
> +    return 0;
> +}

Regards,
-Gonglei
diff mbox

Patch

diff --git a/crypto/Makefile.objs b/crypto/Makefile.objs
index 9f70294..b050138 100644
--- a/crypto/Makefile.objs
+++ b/crypto/Makefile.objs
@@ -2,3 +2,4 @@  util-obj-y += init.o
 util-obj-y += hash.o
 util-obj-y += aes.o
 util-obj-y += desrfb.o
+util-obj-y += cipher.o
diff --git a/crypto/cipher-builtin.c b/crypto/cipher-builtin.c
new file mode 100644
index 0000000..f0bf339
--- /dev/null
+++ b/crypto/cipher-builtin.c
@@ -0,0 +1,400 @@ 
+/*
+ * QEMU Crypto cipher built-in 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 "crypto/aes.h"
+#include "crypto/desrfb.h"
+
+#include <glib/gi18n.h>
+
+typedef struct QCryptoCipherBuiltinAES QCryptoCipherBuiltinAES;
+struct QCryptoCipherBuiltinAES {
+    AES_KEY encrypt_key;
+    AES_KEY decrypt_key;
+    uint8_t *iv;
+    size_t niv;
+};
+typedef struct QCryptoCipherBuiltinDESRFB QCryptoCipherBuiltinDESRFB;
+struct QCryptoCipherBuiltinDESRFB {
+    uint8_t *key;
+    size_t nkey;
+};
+
+typedef struct QCryptoCipherBuiltin QCryptoCipherBuiltin;
+struct QCryptoCipherBuiltin {
+    union {
+        QCryptoCipherBuiltinAES aes;
+        QCryptoCipherBuiltinDESRFB desrfb;
+    } state;
+    void (*free)(QCryptoCipher *cipher);
+    int (*setiv)(QCryptoCipher *cipher,
+                 const uint8_t *iv, size_t niv,
+                 Error **errp);
+    int (*encrypt)(QCryptoCipher *cipher,
+                   const void *in,
+                   void *out,
+                   size_t len,
+                   Error **errp);
+    int (*decrypt)(QCryptoCipher *cipher,
+                   const void *in,
+                   void *out,
+                   size_t len,
+                   Error **errp);
+};
+
+
+static void qcrypto_cipher_free_aes(QCryptoCipher *cipher)
+{
+    QCryptoCipherBuiltin *ctxt = cipher->opaque;
+
+    g_free(ctxt->state.aes.iv);
+    g_free(ctxt);
+    cipher->opaque = NULL;
+}
+
+
+static int qcrypto_cipher_encrypt_aes(QCryptoCipher *cipher,
+                                      const void *in,
+                                      void *out,
+                                      size_t len,
+                                      Error **errp)
+{
+    QCryptoCipherBuiltin *ctxt = cipher->opaque;
+
+    if (cipher->mode == QCRYPTO_CIPHER_MODE_ECB) {
+        const uint8_t *inptr = in;
+        uint8_t *outptr = out;
+        while (len) {
+            if (len > AES_BLOCK_SIZE) {
+                AES_encrypt(inptr, outptr, &ctxt->state.aes.encrypt_key);
+                inptr += AES_BLOCK_SIZE;
+                outptr += AES_BLOCK_SIZE;
+                len -= AES_BLOCK_SIZE;
+            } else {
+                uint8_t tmp1[AES_BLOCK_SIZE], tmp2[AES_BLOCK_SIZE];
+                memcpy(tmp1, inptr, len);
+                /* Fill with 0 to avoid valgrind uninitialized reads */
+                memset(tmp1 + len, 0, sizeof(tmp1) - len);
+                AES_encrypt(tmp1, tmp2, &ctxt->state.aes.encrypt_key);
+                memcpy(outptr, tmp2, len);
+                len = 0;
+            }
+        }
+    } else {
+        AES_cbc_encrypt(in, out, len,
+                        &ctxt->state.aes.encrypt_key,
+                        ctxt->state.aes.iv, 1);
+    }
+
+    return 0;
+}
+
+
+static int qcrypto_cipher_decrypt_aes(QCryptoCipher *cipher,
+                                      const void *in,
+                                      void *out,
+                                      size_t len,
+                                      Error **errp)
+{
+    QCryptoCipherBuiltin *ctxt = cipher->opaque;
+
+    if (cipher->mode == QCRYPTO_CIPHER_MODE_ECB) {
+        const uint8_t *inptr = in;
+        uint8_t *outptr = out;
+        while (len) {
+            if (len > AES_BLOCK_SIZE) {
+                AES_decrypt(inptr, outptr, &ctxt->state.aes.encrypt_key);
+                inptr += AES_BLOCK_SIZE;
+                outptr += AES_BLOCK_SIZE;
+                len -= AES_BLOCK_SIZE;
+            } else {
+                uint8_t tmp1[AES_BLOCK_SIZE], tmp2[AES_BLOCK_SIZE];
+                memcpy(tmp1, inptr, len);
+                /* Fill with 0 to avoid valgrind uninitialized reads */
+                memset(tmp1 + len, 0, sizeof(tmp1) - len);
+                AES_decrypt(tmp1, tmp2, &ctxt->state.aes.encrypt_key);
+                memcpy(outptr, tmp2, len);
+                len = 0;
+            }
+        }
+    } else {
+        AES_cbc_encrypt(in, out, len,
+                        &ctxt->state.aes.encrypt_key,
+                        ctxt->state.aes.iv, 1);
+    }
+
+    return 0;
+}
+
+static int qcrypto_cipher_setiv_aes(QCryptoCipher *cipher,
+                                     const uint8_t *iv, size_t niv,
+                                     Error **errp)
+{
+    QCryptoCipherBuiltin *ctxt = cipher->opaque;
+    if (niv != 16) {
+        error_setg(errp, _("IV must be 16 bytes not %zu"), niv);
+        return -1;
+    }
+
+    g_free(ctxt->state.aes.iv);
+    ctxt->state.aes.iv = g_new0(uint8_t, niv);
+    memcpy(ctxt->state.aes.iv, iv, niv);
+    ctxt->state.aes.niv = niv;
+
+    return 0;
+}
+
+
+
+
+static int qcrypto_cipher_init_aes(QCryptoCipher *cipher,
+                                   const uint8_t *key, size_t nkey,
+                                   Error **errp)
+{
+    QCryptoCipherBuiltin *ctxt;
+
+    if (cipher->mode != QCRYPTO_CIPHER_MODE_CBC &&
+        cipher->mode != QCRYPTO_CIPHER_MODE_ECB) {
+        error_setg(errp, _("Unsupported cipher mode %d"), cipher->mode);
+        return -1;
+    }
+
+    ctxt = g_new0(QCryptoCipherBuiltin, 1);
+
+    if (AES_set_encrypt_key(key, nkey * 8, &ctxt->state.aes.encrypt_key) != 0) {
+        error_setg(errp, "%s", _("Failed to set encryption key"));
+        goto error;
+    }
+
+    if (AES_set_decrypt_key(key, nkey * 8, &ctxt->state.aes.decrypt_key) != 0) {
+        error_setg(errp, "%s", _("Failed to set decryption key"));
+        goto error;
+    }
+
+    ctxt->free = qcrypto_cipher_free_aes;
+    ctxt->setiv = qcrypto_cipher_setiv_aes;
+    ctxt->encrypt = qcrypto_cipher_encrypt_aes;
+    ctxt->decrypt = qcrypto_cipher_decrypt_aes;
+
+    cipher->opaque = ctxt;
+
+    return 0;
+
+ error:
+    g_free(ctxt);
+    return -1;
+}
+
+
+static void qcrypto_cipher_free_des_rfb(QCryptoCipher *cipher)
+{
+    QCryptoCipherBuiltin *ctxt = cipher->opaque;
+
+    g_free(ctxt->state.desrfb.key);
+    g_free(ctxt);
+    cipher->opaque = NULL;
+}
+
+
+static int qcrypto_cipher_encrypt_des_rfb(QCryptoCipher *cipher,
+                                          const void *in,
+                                          void *out,
+                                          size_t len,
+                                          Error **errp)
+{
+    QCryptoCipherBuiltin *ctxt = cipher->opaque;
+    size_t i;
+
+    deskey(ctxt->state.desrfb.key, EN0);
+
+    if (len % 8) {
+        error_setg(errp, _("Buffer size must be multiple of 8 not %zu"),
+                   len);
+        return -1;
+    }
+
+    for (i = 0; i < len; i += 8) {
+        des((void *)in + i, out + i);
+    }
+
+    return 0;
+}
+
+
+static int qcrypto_cipher_decrypt_des_rfb(QCryptoCipher *cipher,
+                                          const void *in,
+                                          void *out,
+                                          size_t len,
+                                          Error **errp)
+{
+    QCryptoCipherBuiltin *ctxt = cipher->opaque;
+    size_t i;
+
+    deskey(ctxt->state.desrfb.key, DE1);
+
+    if (len % 8) {
+        error_setg(errp, _("Buffer size must be multiple of 8 not %zu"),
+                   len);
+        return -1;
+    }
+
+    for (i = 0; i < len; i += 8) {
+        des((void *)in + i, out + i);
+    }
+
+    return 0;
+}
+
+
+static int qcrypto_cipher_setiv_des_rfb(QCryptoCipher *cipher,
+                                        const uint8_t *iv, size_t niv,
+                                        Error **errp)
+{
+    error_setg(errp, "%s", _("Setting IV is not supported"));
+    return -1;
+}
+
+
+static int qcrypto_cipher_init_des_rfb(QCryptoCipher *cipher,
+                                       const uint8_t *key, size_t nkey,
+                                       Error **errp)
+{
+    QCryptoCipherBuiltin *ctxt;
+
+    if (cipher->mode != QCRYPTO_CIPHER_MODE_ECB) {
+        error_setg(errp, _("Unsupported cipher mode %d"), cipher->mode);
+        return -1;
+    }
+
+    ctxt = g_new0(QCryptoCipherBuiltin, 1);
+
+    ctxt->state.desrfb.key = g_new0(uint8_t, nkey);
+    memcpy(ctxt->state.desrfb.key, key, nkey);
+    ctxt->state.desrfb.nkey = nkey;
+
+    ctxt->free = qcrypto_cipher_free_des_rfb;
+    ctxt->setiv = qcrypto_cipher_setiv_des_rfb;
+    ctxt->encrypt = qcrypto_cipher_encrypt_des_rfb;
+    ctxt->decrypt = qcrypto_cipher_decrypt_des_rfb;
+
+    cipher->opaque = ctxt;
+
+    return 0;
+}
+
+
+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;
+
+    cipher = g_new0(QCryptoCipher, 1);
+    cipher->alg = alg;
+    cipher->mode = mode;
+
+    if (!qcrypto_cipher_validate_key_length(alg, nkey, errp)) {
+        goto error;
+    }
+
+    switch (cipher->alg) {
+    case QCRYPTO_CIPHER_ALG_DES_RFB:
+        if (qcrypto_cipher_init_des_rfb(cipher, key, nkey, errp) < 0) {
+            goto error;
+        }
+        break;
+    case QCRYPTO_CIPHER_ALG_AES_128:
+    case QCRYPTO_CIPHER_ALG_AES_192:
+    case QCRYPTO_CIPHER_ALG_AES_256:
+        if (qcrypto_cipher_init_aes(cipher, key, nkey, errp) < 0) {
+            goto error;
+        }
+        break;
+    default:
+        error_setg(errp,
+                   _("Unsupported cipher algorithm %d"), cipher->alg);
+        goto error;
+    }
+
+    return cipher;
+
+ error:
+    g_free(cipher);
+    return NULL;
+}
+
+void qcrypto_cipher_free(QCryptoCipher *cipher)
+{
+    QCryptoCipherBuiltin *ctxt = cipher->opaque;
+    if (!cipher) {
+        return;
+    }
+
+    ctxt->free(cipher);
+    g_free(cipher);
+}
+
+
+int qcrypto_cipher_encrypt(QCryptoCipher *cipher,
+                           const void *in,
+                           void *out,
+                           size_t len,
+                           Error **errp)
+{
+    QCryptoCipherBuiltin *ctxt = cipher->opaque;
+
+    return ctxt->encrypt(cipher, in, out, len, errp);
+}
+
+
+int qcrypto_cipher_decrypt(QCryptoCipher *cipher,
+                           const void *in,
+                           void *out,
+                           size_t len,
+                           Error **errp)
+{
+    QCryptoCipherBuiltin *ctxt = cipher->opaque;
+
+    return ctxt->decrypt(cipher, in, out, len, errp);
+}
+
+
+int qcrypto_cipher_setiv(QCryptoCipher *cipher,
+                         const uint8_t *iv, size_t niv,
+                         Error **errp)
+{
+    QCryptoCipherBuiltin *ctxt = cipher->opaque;
+
+    return ctxt->setiv(cipher, iv, niv, errp);
+}
diff --git a/crypto/cipher.c b/crypto/cipher.c
new file mode 100644
index 0000000..8f41569
--- /dev/null
+++ b/crypto/cipher.c
@@ -0,0 +1,50 @@ 
+/*
+ * QEMU Crypto cipher 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 "crypto/cipher-internal.h"
+
+#include "crypto/cipher-builtin.c"
+
+
+static size_t alg_key_len[QCRYPTO_CIPHER_ALG_LAST] = {
+    [QCRYPTO_CIPHER_ALG_AES_128] = 16,
+    [QCRYPTO_CIPHER_ALG_AES_192] = 24,
+    [QCRYPTO_CIPHER_ALG_AES_256] = 32,
+    [QCRYPTO_CIPHER_ALG_DES_RFB] = 8,
+};
+
+bool qcrypto_cipher_validate_key_length(QCryptoCipherAlgorithm alg,
+                                        size_t nkey,
+                                        Error **errp)
+{
+    if (alg < 0 ||
+        alg >= QCRYPTO_CIPHER_ALG_LAST) {
+        error_setg(errp, _("Cipher algorithm %d out of range"),
+                   alg);
+        return false;
+    }
+
+    if (alg_key_len[alg] != nkey) {
+        error_setg(errp, _("Cipher key length %zu should be %zu"),
+                   alg_key_len[alg], nkey);
+        return false;
+    }
+    return true;
+}
diff --git a/include/crypto/cipher.h b/include/crypto/cipher.h
new file mode 100644
index 0000000..b4d714f
--- /dev/null
+++ b/include/crypto/cipher.h
@@ -0,0 +1,210 @@ 
+/*
+ * QEMU Crypto cipher 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/>.
+ *
+ */
+
+#ifndef QCRYPTO_CIPHER_H__
+#define QCRYPTO_CIPHER_H__
+
+#include "qemu-common.h"
+#include "qapi/error.h"
+
+typedef struct QCryptoCipher QCryptoCipher;
+
+typedef enum {
+    QCRYPTO_CIPHER_ALG_AES_128,
+    QCRYPTO_CIPHER_ALG_AES_192,
+    QCRYPTO_CIPHER_ALG_AES_256,
+    QCRYPTO_CIPHER_ALG_DES_RFB, /* A stupid variant on DES for VNC */
+
+    QCRYPTO_CIPHER_ALG_LAST
+} QCryptoCipherAlgorithm;
+
+typedef enum {
+    QCRYPTO_CIPHER_MODE_ECB,
+    QCRYPTO_CIPHER_MODE_CBC,
+
+    QCRYPTO_CIPHER_MODE_LAST
+} QCryptoCipherMode;
+
+/**
+ * QCryptoCipher:
+ *
+ * The QCryptoCipher object provides a way to perform encryption
+ * and decryption of data, with a standard API, regardless of the
+ * algorithm used. It further isolates the calling code from the
+ * details of the specific underlying implementation, whether
+ * built-in, libgcrypt or nettle.
+ *
+ * Each QCryptoCipher object is capable of performing both
+ * encryption and decryption, and can operate in a number
+ * or modes including ECB, CBC.
+ *
+ * <example>
+ *   <title>Encrypting data with AES-128 in CBC mode</title>
+ *   <programlisting>
+ * QCryptoCipher *cipher;
+ * uint8_t key = ....;
+ * size_t keylen = 16;
+ * uint8_t iv = ....;
+ *
+ * if (!qcrypto_cipher_supports(QCRYPTO_CIPHER_ALG_AES_128)) {
+ *    error_report(errp, "Feature <blah> requires AES cipher support");
+ *    return -1;
+ * }
+ *
+ * cipher = qcrypto_cipher_new(QCRYPTO_CIPHER_ALG_AES_128,
+ *                             QCRYPTO_CIPHER_MODE_CBC,
+ *                             key, keylen,
+ *                             errp);
+ * if (!cipher) {
+ *    return -1;
+ * }
+ *
+ * if (qcrypto_cipher_set_iv(cipher, iv, keylen, errp) < 0) {
+ *    return -1;
+ * }
+ *
+ * if (qcrypto_cipher_encrypt(cipher, rawdata, encdata, datalen, errp) < 0) {
+ *    return -1;
+ * }
+ *
+ * qcrypto_cipher_free(cipher);
+ *   </programlisting>
+ * </example>
+ *
+ */
+
+struct QCryptoCipher {
+    QCryptoCipherAlgorithm alg;
+    QCryptoCipherMode mode;
+    void *opaque;
+};
+
+/**
+ * qcrypto_cipher_supports:
+ * @alg: the cipher algorithm
+ *
+ * Determine if @alg cipher algorithm is supported by the
+ * current configured build
+ *
+ * Returns: true if the algorithm is supported, false otherwise
+ */
+bool qcrypto_cipher_supports(QCryptoCipherAlgorithm alg);
+
+
+/**
+ * qcrypto_cipher_new:
+ * @alg: the cipher algorithm
+ * @mode: the cipher usage mode
+ * @key: the private key bytes
+ * @nkey: the length of @key
+ * @errp: pointer to an uninitialized error object
+ *
+ * Creates a new cipher object for encrypting/decrypting
+ * data with the algorithm @alg in the usage mode @mode.
+ *
+ * The @key parameter provides the bytes representing
+ * the encryption/decryption key to use. The @nkey parameter
+ * specifies the length of @key in bytes. Each algorithm has
+ * one or more valid key lengths, and it is an error to provide
+ * a key of the incorrect length.
+ *
+ * The returned cipher object must be released with
+ * qcrypto_cipher_free() when no longer required
+ *
+ * Returns: a new cipher object, or NULL on error
+ */
+QCryptoCipher *qcrypto_cipher_new(QCryptoCipherAlgorithm alg,
+                                  QCryptoCipherMode mode,
+                                  const uint8_t *key, size_t nkey,
+                                  Error **errp);
+
+/**
+ * qcrypto_cipher_free:
+ * @cipher: the cipher object
+ *
+ * Release the memory associated with @cipher that
+ * was previously allocated by qcrypto_cipher_new()
+ */
+void qcrypto_cipher_free(QCryptoCipher *cipher);
+
+/**
+ * qcrypto_cipher_encrypt:
+ * @cipher: the cipher object
+ * @in: buffer holding the plain text input data
+ * @out: buffer to fill with the cipher text output data
+ * @len: the length of @in and @out buffers
+ * @errp: pointer to an uninitialized error object
+ *
+ * Encrypts the plain text stored in @in, filling
+ * @out with the resulting ciphered text. Both the
+ * @in and @out buffers must have the same size,
+ * given by @len.
+ *
+ * Returns: 0 on success, or -1 on error
+ */
+int qcrypto_cipher_encrypt(QCryptoCipher *cipher,
+                           const void *in,
+                           void *out,
+                           size_t len,
+                           Error **errp);
+
+
+/**
+ * qcrypto_cipher_decrypt:
+ * @cipher: the cipher object
+ * @in: buffer holding the cipher text input data
+ * @out: buffer to fill with the plain text output data
+ * @len: the length of @in and @out buffers
+ * @errp: pointer to an uninitialized error object
+ *
+ * Decrypts the cipher text stored in @in, filling
+ * @out with the resulting plain text. Both the
+ * @in and @out buffers must have the same size,
+ * given by @len.
+ *
+ * Returns: 0 on success, or -1 on error
+ */
+int qcrypto_cipher_decrypt(QCryptoCipher *cipher,
+                           const void *in,
+                           void *out,
+                           size_t len,
+                           Error **errp);
+
+/**
+ * qcrypto_cipher_setiv:
+ * @cipher: the cipher object
+ * @iv: the initialization vector bytes
+ * @niv: the length of @iv
+ * @errpr: pointer to an uninitialized error object
+ *
+ * If the @cipher object is setup to use a mode that requires
+ * initialization vectors, this sets the initialization vector
+ * bytes. The @iv data should have the same length as the
+ * cipher key used when originally constructing the cipher
+ * object. It is an error to set an initialization vector
+ * if the cipher mode does not require one.
+ *
+ * Returns: 0 on success, -1 on error
+ */
+int qcrypto_cipher_setiv(QCryptoCipher *cipher,
+                         const uint8_t *iv, size_t niv,
+                         Error **errp);
+
+#endif /* QCRYPTO_CIPHER_H__ */
diff --git a/tests/.gitignore b/tests/.gitignore
index 12d2373..e93148e 100644
--- a/tests/.gitignore
+++ b/tests/.gitignore
@@ -9,6 +9,7 @@  rcutorture
 test-aio
 test-bitops
 test-coroutine
+test-crypto-cipher
 test-crypto-hash
 test-cutils
 test-hbitmap
diff --git a/tests/Makefile b/tests/Makefile
index 05f1dff..39d3e78 100644
--- a/tests/Makefile
+++ b/tests/Makefile
@@ -73,6 +73,7 @@  gcov-files-test-qemu-opts-y = qom/test-qemu-opts.c
 check-unit-y += tests/test-write-threshold$(EXESUF)
 gcov-files-test-write-threshold-y = block/write-threshold.c
 check-unit-$(CONFIG_GNUTLS_HASH) += tests/test-crypto-hash$(EXESUF)
+check-unit-y += tests/test-crypto-cipher$(EXESUF)
 
 check-block-$(CONFIG_POSIX) += tests/qemu-iotests-quick.sh
 
@@ -335,6 +336,7 @@  tests/test-opts-visitor$(EXESUF): tests/test-opts-visitor.o $(test-qapi-obj-y) l
 tests/test-mul64$(EXESUF): tests/test-mul64.o libqemuutil.a
 tests/test-bitops$(EXESUF): tests/test-bitops.o libqemuutil.a
 tests/test-crypto-hash$(EXESUF): tests/test-crypto-hash.o libqemuutil.a libqemustub.a
+tests/test-crypto-cipher$(EXESUF): tests/test-crypto-cipher.o libqemuutil.a libqemustub.a
 
 libqos-obj-y = tests/libqos/pci.o tests/libqos/fw_cfg.o tests/libqos/malloc.o
 libqos-obj-y += tests/libqos/i2c.o tests/libqos/libqos.o
diff --git a/tests/test-crypto-cipher.c b/tests/test-crypto-cipher.c
new file mode 100644
index 0000000..f9b1a03
--- /dev/null
+++ b/tests/test-crypto-cipher.c
@@ -0,0 +1,290 @@ 
+/*
+ * QEMU Crypto cipher 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 <glib.h>
+
+#include "crypto/init.h"
+#include "crypto/cipher.h"
+
+typedef struct QCryptoCipherTestData QCryptoCipherTestData;
+struct QCryptoCipherTestData {
+    const char *path;
+    QCryptoCipherAlgorithm alg;
+    QCryptoCipherMode mode;
+    const char *key;
+    const char *plaintext;
+    const char *ciphertext;
+    const char *iv;
+};
+
+/* AES test data comes from appendix F of:
+ *
+ * http://csrc.nist.gov/publications/nistpubs/800-38a/sp800-38a.pdf
+ */
+static QCryptoCipherTestData test_data[] = {
+    {
+        /* NIST F.1.1 ECB-AES128.Encrypt */
+        .path = "/crypto/cipher/aes-ecb-128",
+        .alg = QCRYPTO_CIPHER_ALG_AES_128,
+        .mode = QCRYPTO_CIPHER_MODE_ECB,
+        .key = "2b7e151628aed2a6abf7158809cf4f3c",
+        .plaintext =
+            "6bc1bee22e409f96e93d7e117393172a"
+            "ae2d8a571e03ac9c9eb76fac45af8e51"
+            "30c81c46a35ce411e5fbc1191a0a52ef"
+            "f69f2445df4f9b17ad2b417be66c3710",
+        .ciphertext =
+            "3ad77bb40d7a3660a89ecaf32466ef97"
+            "f5d3d58503b9699de785895a96fdbaaf"
+            "43b1cd7f598ece23881b00e3ed030688"
+            "7b0c785e27e8ad3f8223207104725dd4"
+    },
+    {
+        /* NIST F.1.3 ECB-AES192.Encrypt */
+        .path = "/crypto/cipher/aes-ecb-192",
+        .alg = QCRYPTO_CIPHER_ALG_AES_192,
+        .mode = QCRYPTO_CIPHER_MODE_ECB,
+        .key = "8e73b0f7da0e6452c810f32b809079e562f8ead2522c6b7b",
+        .plaintext  =
+            "6bc1bee22e409f96e93d7e117393172a"
+            "ae2d8a571e03ac9c9eb76fac45af8e51"
+            "30c81c46a35ce411e5fbc1191a0a52ef"
+            "f69f2445df4f9b17ad2b417be66c3710",
+        .ciphertext =
+            "bd334f1d6e45f25ff712a214571fa5cc"
+            "974104846d0ad3ad7734ecb3ecee4eef"
+            "ef7afd2270e2e60adce0ba2face6444e"
+            "9a4b41ba738d6c72fb16691603c18e0e"
+    },
+    {
+        /* NIST F.1.5 ECB-AES256.Encrypt */
+        .path = "/crypto/cipher/aes-ecb-256",
+        .alg = QCRYPTO_CIPHER_ALG_AES_256,
+        .mode = QCRYPTO_CIPHER_MODE_ECB,
+        .key =
+            "603deb1015ca71be2b73aef0857d7781"
+            "1f352c073b6108d72d9810a30914dff4",
+        .plaintext  =
+            "6bc1bee22e409f96e93d7e117393172a"
+            "ae2d8a571e03ac9c9eb76fac45af8e51"
+            "30c81c46a35ce411e5fbc1191a0a52ef"
+            "f69f2445df4f9b17ad2b417be66c3710",
+        .ciphertext =
+            "f3eed1bdb5d2a03c064b5a7e3db181f8"
+            "591ccb10d410ed26dc5ba74a31362870"
+            "b6ed21b99ca6f4f9f153e7b1beafed1d"
+            "23304b7a39f9f3ff067d8d8f9e24ecc7",
+    },
+    {
+        /* NIST F.2.1 CBC-AES128.Encrypt */
+        .path = "/crypto/cipher/aes-cbc-128",
+        .alg = QCRYPTO_CIPHER_ALG_AES_128,
+        .mode = QCRYPTO_CIPHER_MODE_CBC,
+        .key = "2b7e151628aed2a6abf7158809cf4f3c",
+        .iv = "000102030405060708090a0b0c0d0e0f",
+        .plaintext  =
+            "6bc1bee22e409f96e93d7e117393172a"
+            "ae2d8a571e03ac9c9eb76fac45af8e51"
+            "30c81c46a35ce411e5fbc1191a0a52ef"
+            "f69f2445df4f9b17ad2b417be66c3710",
+        .ciphertext =
+            "7649abac8119b246cee98e9b12e9197d"
+            "5086cb9b507219ee95db113a917678b2"
+            "73bed6b8e3c1743b7116e69e22229516"
+            "3ff1caa1681fac09120eca307586e1a7",
+    },
+    {
+        /* NIST F.2.3 CBC-AES128.Encrypt */
+        .path = "/crypto/cipher/aes-cbc-192",
+        .alg = QCRYPTO_CIPHER_ALG_AES_192,
+        .mode = QCRYPTO_CIPHER_MODE_CBC,
+        .key = "8e73b0f7da0e6452c810f32b809079e562f8ead2522c6b7b",
+        .iv = "000102030405060708090a0b0c0d0e0f",
+        .plaintext  =
+            "6bc1bee22e409f96e93d7e117393172a"
+            "ae2d8a571e03ac9c9eb76fac45af8e51"
+            "30c81c46a35ce411e5fbc1191a0a52ef"
+            "f69f2445df4f9b17ad2b417be66c3710",
+        .ciphertext =
+            "4f021db243bc633d7178183a9fa071e8"
+            "b4d9ada9ad7dedf4e5e738763f69145a"
+            "571b242012fb7ae07fa9baac3df102e0"
+            "08b0e27988598881d920a9e64f5615cd",
+    },
+    {
+        /* NIST F.2.5 CBC-AES128.Encrypt */
+        .path = "/crypto/cipher/aes-cbc-256",
+        .alg = QCRYPTO_CIPHER_ALG_AES_256,
+        .mode = QCRYPTO_CIPHER_MODE_CBC,
+        .key =
+            "603deb1015ca71be2b73aef0857d7781"
+            "1f352c073b6108d72d9810a30914dff4",
+        .iv = "000102030405060708090a0b0c0d0e0f",
+        .plaintext  =
+            "6bc1bee22e409f96e93d7e117393172a"
+            "ae2d8a571e03ac9c9eb76fac45af8e51"
+            "30c81c46a35ce411e5fbc1191a0a52ef"
+            "f69f2445df4f9b17ad2b417be66c3710",
+        .ciphertext =
+            "f58c4c04d6e5f1ba779eabfb5f7bfbd6"
+            "9cfc4e967edb808d679f777bc6702c7d"
+            "39f23369a9d9bacfa530e26304231461"
+            "b2eb05e2c39be9fcda6c19078c6a9d1b",
+    },
+    {
+        .path = "/crypto/cipher/des-rfb-ecb-56",
+        .alg = QCRYPTO_CIPHER_ALG_DES_RFB,
+        .mode = QCRYPTO_CIPHER_MODE_ECB,
+        .key = "0123456789abcdef",
+        .plaintext =
+            "6bc1bee22e409f96e93d7e117393172a"
+            "ae2d8a571e03ac9c9eb76fac45af8e51"
+            "30c81c46a35ce411e5fbc1191a0a52ef"
+            "f69f2445df4f9b17ad2b417be66c3710",
+        .ciphertext =
+            "8f346aaf64eaf24040720d80648c52e7"
+            "aefc616be53ab1a3d301e69d91e01838"
+            "ffd29f1bb5596ad94ea2d8e6196b7f09"
+            "30d8ed0bf2773af36dd82a6280c20926",
+    },
+};
+
+
+static inline int unhex(char c)
+{
+    if (c >= 'a' && c <= 'f') {
+        return 10 + (c - 'a');
+    }
+    if (c >= 'A' && c <= 'F') {
+        return 10 + (c - 'A');
+    }
+    return c - '0';
+}
+
+static inline char hex(int i)
+{
+    if (i < 10) {
+        return '0' + i;
+    }
+    return 'a' + (i - 10);
+}
+
+static size_t unhex_string(const char *hexstr,
+                           uint8_t **data)
+{
+    size_t len;
+    size_t i;
+
+    if (!hexstr) {
+        *data = NULL;
+        return 0;
+    }
+
+    len = strlen(hexstr);
+    *data = g_new0(uint8_t, len / 2);
+
+    for (i = 0; i < len; i += 2) {
+        (*data)[i/2] = (unhex(hexstr[i]) << 4) | unhex(hexstr[i+1]);
+    }
+    return len / 2;
+}
+
+static char *hex_string(const uint8_t *bytes,
+                        size_t len)
+{
+    char *hexstr = g_new0(char, len * 2 + 1);
+    size_t i;
+
+    for (i = 0; i < len; i++) {
+        hexstr[i*2] = hex((bytes[i] >> 4) & 0xf);
+        hexstr[i*2+1] = hex(bytes[i] & 0xf);
+    }
+    hexstr[len*2] = '\0';
+
+    return hexstr;
+}
+
+static void test_cipher(const void *opaque)
+{
+    const QCryptoCipherTestData *data = opaque;
+
+    QCryptoCipher *cipher;
+    Error *err = NULL;
+    uint8_t *key, *iv, *ciphertext, *plaintext, *outtext;
+    size_t nkey, niv, nciphertext, nplaintext;
+    char *outtexthex;
+
+    g_test_message("foo");
+    nkey = unhex_string(data->key, &key);
+    niv = unhex_string(data->iv, &iv);
+    nciphertext = unhex_string(data->ciphertext, &ciphertext);
+    nplaintext = unhex_string(data->plaintext, &plaintext);
+
+    g_assert(nciphertext == nplaintext);
+
+    outtext = g_new0(uint8_t, nciphertext);
+
+    cipher = qcrypto_cipher_new(
+        data->alg, data->mode,
+        key, nkey,
+        &err);
+    g_assert(cipher != NULL);
+    g_assert(err == NULL);
+
+
+    if (iv) {
+        g_assert(qcrypto_cipher_setiv(cipher,
+                                      iv, niv,
+                                      &err) == 0);
+        g_assert(err == NULL);
+    }
+    g_assert(qcrypto_cipher_encrypt(cipher,
+                                    plaintext,
+                                    outtext,
+                                    nplaintext,
+                                    &err) == 0);
+    g_assert(err == NULL);
+
+    outtexthex = hex_string(outtext, nciphertext);
+
+    g_assert_cmpstr(outtexthex, ==, data->ciphertext);
+
+    g_free(outtext);
+    g_free(outtexthex);
+    g_free(key);
+    g_free(iv);
+    g_free(ciphertext);
+    g_free(plaintext);
+    qcrypto_cipher_free(cipher);
+}
+
+int main(int argc, char **argv)
+{
+    size_t i;
+
+    g_test_init(&argc, &argv, NULL);
+
+    g_assert(qcrypto_init(NULL) == 0);
+
+    for (i = 0; i < G_N_ELEMENTS(test_data); i++) {
+        g_test_add_data_func(test_data[i].path, &test_data[i], test_cipher);
+    }
+    return g_test_run();
+}