These changes are the raw update to qemu-2.6.
[kvmfornfv.git] / qemu / crypto / cipher-gcrypt.c
index 8cfc562..ede2f70 100644 (file)
@@ -18,6 +18,9 @@
  *
  */
 
+#include "qemu/osdep.h"
+#include "crypto/xts.h"
+
 #include <gcrypt.h>
 
 
@@ -28,12 +31,25 @@ bool qcrypto_cipher_supports(QCryptoCipherAlgorithm alg)
     case QCRYPTO_CIPHER_ALG_AES_128:
     case QCRYPTO_CIPHER_ALG_AES_192:
     case QCRYPTO_CIPHER_ALG_AES_256:
+    case QCRYPTO_CIPHER_ALG_CAST5_128:
+    case QCRYPTO_CIPHER_ALG_SERPENT_128:
+    case QCRYPTO_CIPHER_ALG_SERPENT_192:
+    case QCRYPTO_CIPHER_ALG_SERPENT_256:
+    case QCRYPTO_CIPHER_ALG_TWOFISH_128:
+    case QCRYPTO_CIPHER_ALG_TWOFISH_256:
         return true;
     default:
         return false;
     }
 }
 
+typedef struct QCryptoCipherGcrypt QCryptoCipherGcrypt;
+struct QCryptoCipherGcrypt {
+    gcry_cipher_hd_t handle;
+    gcry_cipher_hd_t tweakhandle;
+    size_t blocksize;
+    uint8_t *iv;
+};
 
 QCryptoCipher *qcrypto_cipher_new(QCryptoCipherAlgorithm alg,
                                   QCryptoCipherMode mode,
@@ -41,12 +57,13 @@ QCryptoCipher *qcrypto_cipher_new(QCryptoCipherAlgorithm alg,
                                   Error **errp)
 {
     QCryptoCipher *cipher;
-    gcry_cipher_hd_t handle;
+    QCryptoCipherGcrypt *ctx;
     gcry_error_t err;
     int gcryalg, gcrymode;
 
     switch (mode) {
     case QCRYPTO_CIPHER_MODE_ECB:
+    case QCRYPTO_CIPHER_MODE_XTS:
         gcrymode = GCRY_CIPHER_MODE_ECB;
         break;
     case QCRYPTO_CIPHER_MODE_CBC:
@@ -57,7 +74,7 @@ QCryptoCipher *qcrypto_cipher_new(QCryptoCipherAlgorithm alg,
         return NULL;
     }
 
-    if (!qcrypto_cipher_validate_key_length(alg, nkey, errp)) {
+    if (!qcrypto_cipher_validate_key_length(alg, mode, nkey, errp)) {
         return NULL;
     }
 
@@ -78,6 +95,30 @@ QCryptoCipher *qcrypto_cipher_new(QCryptoCipherAlgorithm alg,
         gcryalg = GCRY_CIPHER_AES256;
         break;
 
+    case QCRYPTO_CIPHER_ALG_CAST5_128:
+        gcryalg = GCRY_CIPHER_CAST5;
+        break;
+
+    case QCRYPTO_CIPHER_ALG_SERPENT_128:
+        gcryalg = GCRY_CIPHER_SERPENT128;
+        break;
+
+    case QCRYPTO_CIPHER_ALG_SERPENT_192:
+        gcryalg = GCRY_CIPHER_SERPENT192;
+        break;
+
+    case QCRYPTO_CIPHER_ALG_SERPENT_256:
+        gcryalg = GCRY_CIPHER_SERPENT256;
+        break;
+
+    case QCRYPTO_CIPHER_ALG_TWOFISH_128:
+        gcryalg = GCRY_CIPHER_TWOFISH128;
+        break;
+
+    case QCRYPTO_CIPHER_ALG_TWOFISH_256:
+        gcryalg = GCRY_CIPHER_TWOFISH;
+        break;
+
     default:
         error_setg(errp, "Unsupported cipher algorithm %d", alg);
         return NULL;
@@ -87,12 +128,22 @@ QCryptoCipher *qcrypto_cipher_new(QCryptoCipherAlgorithm alg,
     cipher->alg = alg;
     cipher->mode = mode;
 
-    err = gcry_cipher_open(&handle, gcryalg, gcrymode, 0);
+    ctx = g_new0(QCryptoCipherGcrypt, 1);
+
+    err = gcry_cipher_open(&ctx->handle, gcryalg, gcrymode, 0);
     if (err != 0) {
         error_setg(errp, "Cannot initialize cipher: %s",
                    gcry_strerror(err));
         goto error;
     }
+    if (cipher->mode == QCRYPTO_CIPHER_MODE_XTS) {
+        err = gcry_cipher_open(&ctx->tweakhandle, 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
@@ -100,22 +151,59 @@ QCryptoCipher *qcrypto_cipher_new(QCryptoCipherAlgorithm alg,
          * bizarre RFB variant of DES :-)
          */
         uint8_t *rfbkey = qcrypto_cipher_munge_des_rfb_key(key, nkey);
-        err = gcry_cipher_setkey(handle, rfbkey, nkey);
+        err = gcry_cipher_setkey(ctx->handle, rfbkey, nkey);
         g_free(rfbkey);
+        ctx->blocksize = 8;
     } else {
-        err = gcry_cipher_setkey(handle, key, nkey);
+        if (cipher->mode == QCRYPTO_CIPHER_MODE_XTS) {
+            nkey /= 2;
+            err = gcry_cipher_setkey(ctx->handle, key, nkey);
+            if (err != 0) {
+                error_setg(errp, "Cannot set key: %s",
+                           gcry_strerror(err));
+                goto error;
+            }
+            err = gcry_cipher_setkey(ctx->tweakhandle, key + nkey, nkey);
+        } else {
+            err = gcry_cipher_setkey(ctx->handle, key, nkey);
+        }
+        if (err != 0) {
+            error_setg(errp, "Cannot set key: %s",
+                       gcry_strerror(err));
+            goto error;
+        }
+        switch (cipher->alg) {
+        case QCRYPTO_CIPHER_ALG_AES_128:
+        case QCRYPTO_CIPHER_ALG_AES_192:
+        case QCRYPTO_CIPHER_ALG_AES_256:
+        case QCRYPTO_CIPHER_ALG_SERPENT_128:
+        case QCRYPTO_CIPHER_ALG_SERPENT_192:
+        case QCRYPTO_CIPHER_ALG_SERPENT_256:
+        case QCRYPTO_CIPHER_ALG_TWOFISH_128:
+        case QCRYPTO_CIPHER_ALG_TWOFISH_256:
+            ctx->blocksize = 16;
+            break;
+        case QCRYPTO_CIPHER_ALG_CAST5_128:
+            ctx->blocksize = 8;
+            break;
+        default:
+            g_assert_not_reached();
+        }
     }
-    if (err != 0) {
-        error_setg(errp, "Cannot set key: %s",
-                   gcry_strerror(err));
-        goto error;
+
+    if (cipher->mode == QCRYPTO_CIPHER_MODE_XTS) {
+        ctx->iv = g_new0(uint8_t, ctx->blocksize);
     }
 
-    cipher->opaque = handle;
+    cipher->opaque = ctx;
     return cipher;
 
  error:
-    gcry_cipher_close(handle);
+    gcry_cipher_close(ctx->handle);
+    if (cipher->mode == QCRYPTO_CIPHER_MODE_XTS) {
+        gcry_cipher_close(ctx->tweakhandle);
+    }
+    g_free(ctx);
     g_free(cipher);
     return NULL;
 }
@@ -123,34 +211,72 @@ QCryptoCipher *qcrypto_cipher_new(QCryptoCipherAlgorithm alg,
 
 void qcrypto_cipher_free(QCryptoCipher *cipher)
 {
-    gcry_cipher_hd_t handle;
+    QCryptoCipherGcrypt *ctx;
     if (!cipher) {
         return;
     }
-    handle = cipher->opaque;
-    gcry_cipher_close(handle);
+    ctx = cipher->opaque;
+    gcry_cipher_close(ctx->handle);
+    if (cipher->mode == QCRYPTO_CIPHER_MODE_XTS) {
+        gcry_cipher_close(ctx->tweakhandle);
+    }
+    g_free(ctx->iv);
+    g_free(ctx);
     g_free(cipher);
 }
 
 
+static void qcrypto_gcrypt_xts_encrypt(const void *ctx,
+                                       size_t length,
+                                       uint8_t *dst,
+                                       const uint8_t *src)
+{
+    gcry_error_t err;
+    err = gcry_cipher_encrypt((gcry_cipher_hd_t)ctx, dst, length, src, length);
+    g_assert(err == 0);
+}
+
+static void qcrypto_gcrypt_xts_decrypt(const void *ctx,
+                                       size_t length,
+                                       uint8_t *dst,
+                                       const uint8_t *src)
+{
+    gcry_error_t err;
+    err = gcry_cipher_decrypt((gcry_cipher_hd_t)ctx, dst, length, src, length);
+    g_assert(err == 0);
+}
+
 int qcrypto_cipher_encrypt(QCryptoCipher *cipher,
                            const void *in,
                            void *out,
                            size_t len,
                            Error **errp)
 {
-    gcry_cipher_hd_t handle = cipher->opaque;
+    QCryptoCipherGcrypt *ctx = 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));
+    if (len % ctx->blocksize) {
+        error_setg(errp, "Length %zu must be a multiple of block size %zu",
+                   len, ctx->blocksize);
         return -1;
     }
 
+    if (cipher->mode == QCRYPTO_CIPHER_MODE_XTS) {
+        xts_encrypt(ctx->handle, ctx->tweakhandle,
+                    qcrypto_gcrypt_xts_encrypt,
+                    qcrypto_gcrypt_xts_decrypt,
+                    ctx->iv, len, out, in);
+    } else {
+        err = gcry_cipher_encrypt(ctx->handle,
+                                  out, len,
+                                  in, len);
+        if (err != 0) {
+            error_setg(errp, "Cannot encrypt data: %s",
+                       gcry_strerror(err));
+            return -1;
+        }
+    }
+
     return 0;
 }
 
@@ -161,18 +287,31 @@ int qcrypto_cipher_decrypt(QCryptoCipher *cipher,
                            size_t len,
                            Error **errp)
 {
-    gcry_cipher_hd_t handle = cipher->opaque;
+    QCryptoCipherGcrypt *ctx = 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));
+    if (len % ctx->blocksize) {
+        error_setg(errp, "Length %zu must be a multiple of block size %zu",
+                   len, ctx->blocksize);
         return -1;
     }
 
+    if (cipher->mode == QCRYPTO_CIPHER_MODE_XTS) {
+        xts_decrypt(ctx->handle, ctx->tweakhandle,
+                    qcrypto_gcrypt_xts_encrypt,
+                    qcrypto_gcrypt_xts_decrypt,
+                    ctx->iv, len, out, in);
+    } else {
+        err = gcry_cipher_decrypt(ctx->handle,
+                                  out, len,
+                                  in, len);
+        if (err != 0) {
+            error_setg(errp, "Cannot decrypt data: %s",
+                       gcry_strerror(err));
+            return -1;
+        }
+    }
+
     return 0;
 }
 
@@ -180,16 +319,26 @@ int qcrypto_cipher_setiv(QCryptoCipher *cipher,
                          const uint8_t *iv, size_t niv,
                          Error **errp)
 {
-    gcry_cipher_hd_t handle = cipher->opaque;
+    QCryptoCipherGcrypt *ctx = 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));
+    if (niv != ctx->blocksize) {
+        error_setg(errp, "Expected IV size %zu not %zu",
+                   ctx->blocksize, niv);
         return -1;
     }
 
+    if (ctx->iv) {
+        memcpy(ctx->iv, iv, niv);
+    } else {
+        gcry_cipher_reset(ctx->handle);
+        err = gcry_cipher_setiv(ctx->handle, iv, niv);
+        if (err != 0) {
+            error_setg(errp, "Cannot set IV: %s",
+                   gcry_strerror(err));
+            return -1;
+        }
+    }
+
     return 0;
 }