Improved type-checking hack in CBC_ENCRYPT and similar macros.

ChangeLog

+2014-12-12  Niels Möller  <nisse@lysator.liu.se>
+
+	* cbc.h (CBC_ENCRYPT, CBC_DECRYPT): Make type-checking hack
+	stricter, warn if type of length argument is smaller than size_t.
+	* ctr.h (CTR_CRYPT): Likewise.
+	* eax.h (EAX_SET_KEY, EAX_SET_NONCE, EAX_UPDATE, EAX_ENCRYPT)
+	(EAX_DECRYPT, EAX_DIGEST): Likewise.
+	* gcm.h (GCM_SET_KEY, GCM_ENCRYPT, GCM_DECRYPT, GCM_DIGEST):
+	Likewise.
+
 2014-11-24  Niels Möller  <nisse@lysator.liu.se>
 
 	* gcm.h (GCM_SET_KEY): Rename macro argument KEY to avoid

cbc.h

@@ -64,14 +64,16 @@ memcpy((ctx)->iv, (data), sizeof((ctx)->iv))
 
 /* NOTE: Avoid using NULL, as we don't include anything defining it. */
 #define CBC_ENCRYPT(self, f, length, dst, src)		\
-(0 ? ((f)(&(self)->ctx, 0, (void *)0, (void *)0))			\
+  (0 ? ((f)(&(self)->ctx, ~(size_t) 0,			\
+	    (uint8_t *) 0, (const uint8_t *) 0))	\
    : cbc_encrypt((void *) &(self)->ctx,			\
 		 (nettle_cipher_func *) (f),		\
 		 sizeof((self)->iv), (self)->iv,	\
 		 (length), (dst), (src)))
 
 #define CBC_DECRYPT(self, f, length, dst, src)		\
-(0 ? ((f)(&(self)->ctx, 0, (void *)0, (void *)0))			\
+  (0 ? ((f)(&(self)->ctx, ~(size_t) 0,			\
+	    (uint8_t *) 0, (const uint8_t *) 0))	\
    : cbc_decrypt((void *) &(self)->ctx,			\
 		 (nettle_cipher_func *) (f),		\
 		 sizeof((self)->iv), (self)->iv,	\

ctr.h

@@ -57,7 +57,8 @@ ctr_crypt(const void *ctx, nettle_cipher_func *f,
 memcpy((ctx)->ctr, (data), sizeof((ctx)->ctr))
 
 #define CTR_CRYPT(self, f, length, dst, src)		\
-(0 ? ((f)(&(self)->ctx, 0, NULL, NULL))			\
+  (0 ? ((f)(&(self)->ctx, ~(size_t) 0,			\
+	  (uint8_t *) 0, (const uint8_t *) 0))		\
    : ctr_crypt((void *) &(self)->ctx,			\
 	       (nettle_cipher_func *) (f),		\
 	       sizeof((self)->ctr), (self)->ctr,	\

eax.h

@@ -114,36 +114,42 @@ eax_digest (struct eax_ctx *eax, const struct eax_key *key,
 #define EAX_SET_KEY(ctx, set_key, encrypt, data)			\
   do {									\
     (set_key)(&(ctx)->cipher, (data));					\
-    if (0) (encrypt) (&(ctx)->cipher, 0, (void *) 0, (void *) 0);	\
+    if (0) (encrypt) (&(ctx)->cipher, ~(size_t) 0,			\
+		      (uint8_t *) 0, (const uint8_t *) 0);		\
     eax_set_key (&(ctx)->key, &(ctx)->cipher, (nettle_cipher_func *) encrypt); \
   } while (0)
 
-#define EAX_SET_NONCE(ctx, encrypt, length, nonce) \
-  (0 ? (encrypt) (&(ctx)->cipher, 0, (void *) 0, (void *) 0)	\
+#define EAX_SET_NONCE(ctx, encrypt, length, nonce)			\
+  (0 ? (encrypt) (&(ctx)->cipher, ~(size_t) 0,				\
+		  (uint8_t *) 0, (const uint8_t *) 0)			\
    : eax_set_nonce (&(ctx)->eax, &(ctx)->key,			\
 		    &(ctx)->cipher, (nettle_cipher_func *) (encrypt),	\
 		    (length), (nonce)))
 
 #define EAX_UPDATE(ctx, encrypt, length, data)				\
-  (0 ? (encrypt) (&(ctx)->cipher, 0, (void *) 0, (void *) 0)		\
+  (0 ? (encrypt) (&(ctx)->cipher, ~(size_t) 0,				\
+		  (uint8_t *) 0, (const uint8_t *) 0)			\
    : eax_update (&(ctx)->eax, &(ctx)->key,				\
 		 &(ctx)->cipher, (nettle_cipher_func *) (encrypt),	\
 		 (length), (data)))
 
 #define EAX_ENCRYPT(ctx, encrypt, length, dst, src)			\
-  (0 ? (encrypt) (&(ctx)->cipher, 0, (void *) 0, (void *) 0)		\
+  (0 ? (encrypt) (&(ctx)->cipher, ~(size_t) 0,				\
+		  (uint8_t *) 0, (const uint8_t *) 0)			\
    : eax_encrypt (&(ctx)->eax, &(ctx)->key,				\
 		 &(ctx)->cipher, (nettle_cipher_func *) (encrypt),	\
 		  (length), (dst), (src)))
 
 #define EAX_DECRYPT(ctx, encrypt, length, dst, src)			\
-  (0 ? (encrypt) (&(ctx)->cipher, 0, (void *) 0, (void *) 0)		\
+  (0 ? (encrypt) (&(ctx)->cipher, ~(size_t) 0,				\
+		  (uint8_t *) 0, (const uint8_t *) 0)			\
    : eax_decrypt (&(ctx)->eax, &(ctx)->key,				\
 		 &(ctx)->cipher, (nettle_cipher_func *) (encrypt),	\
 		  (length), (dst), (src)))
 
 #define EAX_DIGEST(ctx, encrypt, length, digest)			\
-  (0 ? (encrypt) (&(ctx)->cipher, 0, (void *) 0, (void *) 0)		\
+  (0 ? (encrypt) (&(ctx)->cipher, ~(size_t) 0,				\
+		  (uint8_t *) 0, (const uint8_t *) 0)			\
    : eax_digest (&(ctx)->eax, &(ctx)->key,				\
 		 &(ctx)->cipher, (nettle_cipher_func *) (encrypt),	\
 		 (length), (digest)))

gcm.h

@@ -151,10 +151,11 @@ gcm_digest(struct gcm_ctx *ctx, const struct gcm_key *key,
   { struct gcm_key key; struct gcm_ctx gcm; type cipher; }
 
 /* NOTE: Avoid using NULL, as we don't include anything defining it. */
-#define GCM_SET_KEY(ctx, set_key, encrypt, gcm_key)			\
+#define GCM_SET_KEY(ctx, set_key, encrypt, gcm_key)		\
   do {								\
-    (set_key)(&(ctx)->cipher, (gcm_key));				\
-    if (0) (encrypt)(&(ctx)->cipher, 0, (void *)0, (void *)0);	\
+    (set_key)(&(ctx)->cipher, (gcm_key));			\
+    if (0) (encrypt)(&(ctx)->cipher, ~(size_t) 0,		\
+		     (uint8_t *) 0, (const uint8_t *) 0);	\
     gcm_set_key(&(ctx)->key, &(ctx)->cipher,			\
 		(nettle_cipher_func *) (encrypt));		\
   } while (0)
@@ -166,19 +167,22 @@ gcm_digest(struct gcm_ctx *ctx, const struct gcm_key *key,
   gcm_update(&(ctx)->gcm, &(ctx)->key, (length), (data))
 
 #define GCM_ENCRYPT(ctx, encrypt, length, dst, src)			\
-  (0 ? (encrypt)(&(ctx)->cipher, 0, (void *)0, (void *)0)		\
+  (0 ? (encrypt)(&(ctx)->cipher, ~(size_t) 0,				\
+		 (uint8_t *) 0, (const uint8_t *) 0)			\
      : gcm_encrypt(&(ctx)->gcm, &(ctx)->key, &(ctx)->cipher,		\
 		   (nettle_cipher_func *) (encrypt),			\
 		   (length), (dst), (src)))
 
 #define GCM_DECRYPT(ctx, encrypt, length, dst, src)			\
-  (0 ? (encrypt)(&(ctx)->cipher, 0, (void *)0, (void *)0)		\
+  (0 ? (encrypt)(&(ctx)->cipher, ~(size_t) 0,				\
+		 (uint8_t *) 0, (const uint8_t *) 0)			\
      : gcm_decrypt(&(ctx)->gcm,  &(ctx)->key, &(ctx)->cipher,		\
 		   (nettle_cipher_func *) (encrypt),			\
 		   (length), (dst), (src)))
 
 #define GCM_DIGEST(ctx, encrypt, length, digest)			\
-  (0 ? (encrypt)(&(ctx)->cipher, 0, (void *)0, (void *)0)		\
+  (0 ? (encrypt)(&(ctx)->cipher, ~(size_t) 0,				\
+		 (uint8_t *) 0, (const uint8_t *) 0)			\
      : gcm_digest(&(ctx)->gcm, &(ctx)->key, &(ctx)->cipher,		\
 		  (nettle_cipher_func *) (encrypt),			\
 		  (length), (digest)))