diff --git a/lib/md5.c b/lib/md5.c
index f3d6e079..75b4fd67 100644
--- a/lib/md5.c
+++ b/lib/md5.c
@@ -17,12 +17,12 @@
 #ifdef CPU_LITTLE_ENDIAN
 #define byteReverse(buf, len)	/* Nothing */
 #else
-void byteReverse(unsigned char *buf, unsigned longs);
+void byteReverse(byte *buf, unsigned longs);
 
 /*
  * Note: this code is harmless on little-endian machines.
  */
-void byteReverse(unsigned char *buf, unsigned longs)
+void byteReverse(byte *buf, unsigned longs)
 {
   u32 t;
   do {
@@ -55,7 +55,7 @@ md5_init(md5_context *ctx)
  * of bytes.
  */
 void
-md5_update(md5_context *ctx, unsigned char const *buf, unsigned len)
+md5_update(md5_context *ctx, byte const *buf, unsigned len)
 {
   u32 t;
 
@@ -72,7 +72,7 @@ md5_update(md5_context *ctx, unsigned char const *buf, unsigned len)
 
   if (t)
   {
-    unsigned char *p = (unsigned char *) ctx->in + t;
+    byte *p = (byte *) ctx->in + t;
 
     t = 64 - t;
     if (len < t)
@@ -110,7 +110,7 @@ byte *
 md5_final(md5_context *ctx)
 {
   unsigned count;
-  unsigned char *p;
+  byte *p;
 
   /* Compute number of bytes mod 64 */
   count = (ctx->bits[0] >> 3) & 0x3F;
@@ -146,7 +146,7 @@ md5_final(md5_context *ctx)
   ((u32 *) ctx->in)[15] = ctx->bits[1];
 
   md5_transform(ctx->buf, (u32 *) ctx->in);
-  byteReverse((unsigned char *) ctx->buf, 4);
+  byteReverse((byte *) ctx->buf, 4);
 
   return (byte*) ctx->buf;
 }
diff --git a/lib/md5.h b/lib/md5.h
index 8ace29cb..78c62c78 100644
--- a/lib/md5.h
+++ b/lib/md5.h
@@ -19,11 +19,11 @@ typedef struct
 {
   u32 buf[4];
   u32 bits[2];
-  unsigned char in[64];
+  byte in[64];
 } md5_context;
 
 void md5_init(md5_context *context);
-void md5_update(md5_context *context, unsigned char const *buf, unsigned len);
+void md5_update(md5_context *context, byte const *buf, unsigned len);
 byte *md5_final(md5_context *context);
 
 void md5_transform(u32 buf[4], u32 const in[16]);
diff --git a/lib/printf.c b/lib/printf.c
index 3eb988fa..a1c36129 100644
--- a/lib/printf.c
+++ b/lib/printf.c
@@ -215,7 +215,7 @@ int bvsnprintf(char *buf, int size, const char *fmt, va_list args)
 			if (!(flags & LEFT))
 				while (--field_width > 0)
 					*str++ = ' ';
-			*str++ = (unsigned char) va_arg(args, int);
+			*str++ = (byte) va_arg(args, int);
 			while (--field_width > 0)
 				*str++ = ' ';
 			continue;
diff --git a/lib/sha256.c b/lib/sha256.c
index 4025c6a0..cd0fef03 100644
--- a/lib/sha256.c
+++ b/lib/sha256.c
@@ -115,7 +115,7 @@ sum1(u32 x)
     32-bit-words. See FIPS 180-2 for details.
  */
 static unsigned int
-sha256_transform_block(sha256_context *ctx, const unsigned char *data)
+sha256_transform_block(sha256_context *ctx, const byte *data)
 {
   static const u32 K[64] = {
       0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5,
@@ -215,7 +215,7 @@ sha256_transform_block(sha256_context *ctx, const unsigned char *data)
 #undef R
 
 static unsigned int
-sha256_transform(void *ctx, const unsigned char *data, size_t nblks)
+sha256_transform(void *ctx, const byte *data, size_t nblks)
 {
   sha256_context *hd = ctx;
   unsigned int burn;
diff --git a/lib/sha256.h b/lib/sha256.h
index 44e4a6d0..ce8f1460 100644
--- a/lib/sha256.h
+++ b/lib/sha256.h
@@ -23,7 +23,7 @@
 #define SHA256_HEX_SIZE		65
 #define SHA256_BLOCK_SIZE 	64
 
-typedef unsigned int sha_transform_fn (void *c, const unsigned char *blks, size_t nblks);
+typedef unsigned int sha_transform_fn (void *c, const byte *blks, size_t nblks);
 
 typedef struct {
   u32  h0,h1,h2,h3,h4,h5,h6,h7;
@@ -51,7 +51,7 @@ byte* sha224_final(sha224_context *ctx)
   return sha256_final(ctx);
 }
 
-static unsigned int sha256_transform(void *ctx, const unsigned char *data, size_t nblks);
+static unsigned int sha256_transform(void *ctx, const byte *data, size_t nblks);
 
 /**
  *	HMAC-SHA256, HMAC-SHA224
diff --git a/lib/sha512.c b/lib/sha512.c
index e917eb98..eea7cda8 100644
--- a/lib/sha512.c
+++ b/lib/sha512.c
@@ -147,7 +147,7 @@ static const u64 k[] =
  * Transform the message W which consists of 16 64-bit-words
  */
 static unsigned int
-sha512_transform_block(sha512_state *hd, const unsigned char *data)
+sha512_transform_block(sha512_state *hd, const byte *data)
 {
   u64 a, b, c, d, e, f, g, h;
   u64 w[16];
@@ -410,7 +410,7 @@ sha512_transform_block(sha512_state *hd, const unsigned char *data)
 }
 
 static unsigned int
-sha512_transform(void *context, const unsigned char *data, size_t nblks)
+sha512_transform(void *context, const byte *data, size_t nblks)
 {
   sha512_context *ctx = context;
   unsigned int burn;
diff --git a/lib/sha512.h b/lib/sha512.h
index e37bbcb6..188850b4 100644
--- a/lib/sha512.h
+++ b/lib/sha512.h
@@ -52,7 +52,7 @@ byte* sha384_final(sha384_context *ctx)
   return sha512_final(ctx);
 }
 
-static unsigned int sha512_transform(void *context, const unsigned char *data, size_t nblks);
+static unsigned int sha512_transform(void *context, const byte *data, size_t nblks);
 
 /**
  *	HMAC-SHA512, HMAC-SHA384
diff --git a/nest/route.h b/nest/route.h
index 87f10ae3..2e6bf741 100644
--- a/nest/route.h
+++ b/nest/route.h
@@ -320,7 +320,7 @@ struct mpnh {
   ip_addr gw;				/* Next hop */
   struct iface *iface;			/* Outgoing interface */
   struct mpnh *next;
-  unsigned char weight;
+  byte weight;
 };
 
 struct rte_src {
diff --git a/proto/ospf/rt.c b/proto/ospf/rt.c
index 495178c0..e68ee0f4 100644
--- a/proto/ospf/rt.c
+++ b/proto/ospf/rt.c
@@ -43,7 +43,7 @@ unresolved_vlink(ort *ort)
 }
 
 static inline struct mpnh *
-new_nexthop(struct ospf_proto *p, ip_addr gw, struct iface *iface, unsigned char weight)
+new_nexthop(struct ospf_proto *p, ip_addr gw, struct iface *iface, byte weight)
 {
   struct mpnh *nh = lp_alloc(p->nhpool, sizeof(struct mpnh));
   nh->gw = gw;
diff --git a/sysdep/bsd/sysio.h b/sysdep/bsd/sysio.h
index df5e0236..c82d7a1e 100644
--- a/sysdep/bsd/sysio.h
+++ b/sysdep/bsd/sysio.h
@@ -130,7 +130,7 @@ static inline void
 sk_process_cmsg4_ttl(sock *s, struct cmsghdr *cm)
 {
   if (cm->cmsg_type == IP_RECVTTL)
-    s->rcv_ttl = * (unsigned char *) CMSG_DATA(cm);
+    s->rcv_ttl = * (byte *) CMSG_DATA(cm);
 }
 
 static inline void