#ifndef _UCW_SHA1_H
#define _UCW_SHA1_H
+/**
+ * Internal SHA1 state.
+ * You should use it just as an opaque handle only.
+ */
typedef struct {
u32 h0,h1,h2,h3,h4;
u32 nblocks;
int count;
} sha1_context;
-void sha1_init(sha1_context *hd);
+void sha1_init(sha1_context *hd); /** Initialize new algorithm run in the @hd context. **/
+/**
+ * Push another @inlen bytes of data pointed to by @inbuf onto the
+ * SHA1 hash currently in @hd. You can call this any times you want on
+ * the same hash (and you do not need to reinitialize it by
+ * @sha1_init()). It has the same effect as concatenating all the data
+ * together and passing them at once.
+ */
void sha1_update(sha1_context *hd, const byte *inbuf, uns inlen);
+/**
+ * No more @sha1_update() calls will be done. This terminates the hash
+ * and returns a pointer to it.
+ *
+ * Note that the pointer points into data in the @hd context. If it ceases
+ * to exist, the pointer becomes invalid.
+ *
+ * To convert the hash to its usual hexadecimal representation, see
+ * <<string:mem_to_hex()>>.
+ */
byte *sha1_final(sha1_context *hd);
-/* One-shot interface */
+/**
+ * A convenience one-shot function for SHA1 hash.
+ * It is equivalent to this snippet of code:
+ *
+ * sha1_context hd;
+ * sha1_init(&hd);
+ * sha1_update(&hd, buffer, length);
+ * memcpy(outbuf, sha1_final(&hd), SHA1_SIZE);
+ */
void sha1_hash_buffer(byte *outbuf, const byte *buffer, uns length);
-/* HMAC */
+/**
+ * SHA1 HMAC message authentication. If you provide @key and @data,
+ * the result will be stored in @outbuf.
+ */
void sha1_hmac(byte *outbuf, const byte *key, uns keylen, const byte *data, uns datalen);
-#define SHA1_SIZE 20
-#define SHA1_HEX_SIZE 41
-#define SHA1_BLOCK_SIZE 64
+#define SHA1_SIZE 20 /** Size of the SHA1 hash in its binary representation **/
+#define SHA1_HEX_SIZE 41 /** Buffer length for a string containing SHA1 in hexadecimal format. **/
+#define SHA1_BLOCK_SIZE 64 /** SHA1 splits input to blocks of this size. **/
#endif