diff --git a/Makefile b/Makefile
index e494601..73d0c37 100644
--- a/Makefile
+++ b/Makefile
@@ -16,7 +16,7 @@ LDLIBS =
 TARGET_LIB = mulithash.a
 TARGET_BIN = multihash
 
-SRCS = errors.c
+SRCS = errors.c hashes.c
 OBJS = $(SRCS:.c=.o)
 
 all: $(TARGET_LIB) $(TARGET_BIN)
diff --git a/hashes.c b/hashes.c
new file mode 100644
index 0000000..3469a88
--- /dev/null
+++ b/hashes.c
@@ -0,0 +1,43 @@
+/* vim: set ts=8 sw=8 noexpandtab: */
+
+
+// list of avaliable hash functions.
+typedef enum {
+	MH_H_SHA1,
+	MH_H_SHA2_256,
+	MH_H_SHA2_512,
+	MH_H_SHA3_512,
+	MH_H_SHA3_384,
+	MH_H_SHA3_256,
+	MH_H_SHA3_224,
+	MH_H_SHAKE_128,
+	MH_H_SHAKE_256,
+	MH_H_BLAKE2B,
+	MH_H_BLAKE2S,
+
+	HM_H_COUNT // number of hash functions
+} mh_hash;
+
+// returns default size in bytes of given hash function
+int mh_hash_default_size(mh_hash hash);
+
+// returns wire format code of given hash function
+int mh_hash_code(mh_hash hash);
+
+typedef struct {
+	mh_hash hash;
+	int code;
+	int length;
+} mh_hashinfo
+
+// decodes code info hash info, leaves length field zeroed
+mh_error mh_hashinfo_from_code(int code, mh_hashinfo *hinfo);
+
+// decodes bytes into hashinfo
+mh_error mh_hashinfo_from_bytes(char bytes[2], mh_hashinfo *hinfo);
+
+
+
+
+
+
diff --git a/hashes.h b/hashes.h
new file mode 100644
index 0000000..09ddeb8
--- /dev/null
+++ b/hashes.h
@@ -0,0 +1,2 @@
+/* vim: set ts=8 sw=8 noexpandtab: */
+