-#include <gcrypt.h>
-
-typedef struct digest {
- int algo;
- int nid;
- uint16_t len;
-} digest_t;
-
-bool digest_open_by_name(struct digest *, const char *);
-bool digest_open_by_nid(struct digest *, int);
-bool digest_open_sha1(struct digest *);
-void digest_close(struct digest *);
-bool digest_create(struct digest *, void *indata, size_t inlen, void *outdata);
-bool digest_verify(struct digest *, void *indata, size_t inlen, void *digestdata);
-int digest_get_nid(const struct digest *);
-size_t digest_length(const struct digest *);
-bool digest_active(const struct digest *);
+#define DIGEST_MAX_SIZE 64
+
+typedef struct digest digest_t;
+
+extern digest_t *digest_open_by_name(const char *name, int maclength) __attribute__ ((__malloc__));
+extern digest_t *digest_open_by_nid(int nid, int maclength) __attribute__ ((__malloc__));
+extern digest_t *digest_open_sha1(int maclength) __attribute__ ((__malloc__));
+extern void digest_close(digest_t *);
+extern bool digest_create(digest_t *, const void *indata, size_t inlen, void *outdata) __attribute__ ((__warn_unused_result__));
+extern bool digest_verify(digest_t *, const void *indata, size_t inlen, const void *digestdata) __attribute__ ((__warn_unused_result__));
+extern bool digest_set_key(digest_t *, const void *key, size_t len) __attribute__ ((__warn_unused_result__));
+extern int digest_get_nid(const digest_t *);
+extern size_t digest_keylength(const digest_t *);
+extern size_t digest_length(const digest_t *);
+extern bool digest_active(const digest_t *);