crypto: fix build with nettle >= 3.0.0

In nettle 3, cbc_encrypt() accepts 'nettle_cipher_func' instead of
'nettle_crypt_func' and these two differ in 'const' qualifier of the
first argument.  The build fails with:

  In file included from crypto/cipher.c:71:0:
  ./crypto/cipher-nettle.c: In function ‘qcrypto_cipher_encrypt’:
  ./crypto/cipher-nettle.c:154:38: error: passing argument 2 of
  ‘nettle_cbc_encrypt’ from incompatible pointer type
           cbc_encrypt(ctx->ctx_encrypt, ctx->alg_encrypt,
                                               ^
  In file included from ./crypto/cipher-nettle.c:24:0,
                   from crypto/cipher.c:71:
  /usr/include/nettle/cbc.h:48:1: note: expected
  ‘void (*)(const void *, size_t, uint8_t *, const uint8_t *)
  but argument is of type
  ‘void (*)(      void *, size_t, uint8_t *, const uint8_t *)

To allow both versions, we switch to the new definition and #if typedef
it for old versions.

Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
Message-Id: <1436548682-9315-2-git-send-email-rkrcmar@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

1 files changed, 10 insertions, 6 deletions

diff --git a/crypto/cipher-nettle.c b/crypto/cipher-nettle.c
index e5a14bc..e61aaa2 100644
--- a/crypto/cipher-nettle.c
+++ b/crypto/cipher-nettle.c
@@ -23,12 +23,16 @@
 #include <nettle/des.h>
 #include <nettle/cbc.h>
 
+#if CONFIG_NETTLE_VERSION_MAJOR < 3
+typedef nettle_crypt_func nettle_cipher_func;
+#endif
+
 typedef struct QCryptoCipherNettle QCryptoCipherNettle;
 struct QCryptoCipherNettle {
     void *ctx_encrypt;
     void *ctx_decrypt;
-    nettle_crypt_func *alg_encrypt;
-    nettle_crypt_func *alg_decrypt;
+    nettle_cipher_func *alg_encrypt;
+    nettle_cipher_func *alg_decrypt;
     uint8_t *iv;
     size_t niv;
 };
@@ -83,8 +87,8 @@ QCryptoCipher *qcrypto_cipher_new(QCryptoCipherAlgorithm alg,
         des_set_key(ctx->ctx_encrypt, rfbkey);
         g_free(rfbkey);
 
-        ctx->alg_encrypt = (nettle_crypt_func *)des_encrypt;
-        ctx->alg_decrypt = (nettle_crypt_func *)des_decrypt;
+        ctx->alg_encrypt = (nettle_cipher_func *)des_encrypt;
+        ctx->alg_decrypt = (nettle_cipher_func *)des_decrypt;
 
         ctx->niv = DES_BLOCK_SIZE;
         break;
@@ -98,8 +102,8 @@ QCryptoCipher *qcrypto_cipher_new(QCryptoCipherAlgorithm alg,
         aes_set_encrypt_key(ctx->ctx_encrypt, nkey, key);
         aes_set_decrypt_key(ctx->ctx_decrypt, nkey, key);
 
-        ctx->alg_encrypt = (nettle_crypt_func *)aes_encrypt;
-        ctx->alg_decrypt = (nettle_crypt_func *)aes_decrypt;
+        ctx->alg_encrypt = (nettle_cipher_func *)aes_encrypt;
+        ctx->alg_decrypt = (nettle_cipher_func *)aes_decrypt;
 
         ctx->niv = AES_BLOCK_SIZE;
         break;