diff --git a/sys/netinet/cc/cc.h b/sys/netinet/cc/cc.h
--- a/sys/netinet/cc/cc.h
+++ b/sys/netinet/cc/cc.h
@@ -121,25 +121,25 @@
 #define CCF_HYSTART_CAN_SH_CWND	0x0800  /* Can hystart when going CSS -> CA slam the cwnd */
 #define CCF_HYSTART_CONS_SSTH	0x1000	/* Should hystart use the more conservative ssthresh */
 
-/* ACK types passed to the ack_received() hook. */
-#define	CC_ACK		0x0001	/* Regular in sequence ACK. */
-#define	CC_DUPACK	0x0002	/* Duplicate ACK. */
-#define	CC_PARTIALACK	0x0004	/* Not yet. */
-#define	CC_SACK		0x0008	/* Not yet. */
+typedef enum {
+	/* ACK types passed to the ack_received() hook. */
+	CC_ACK =	0x0001,	/* Regular in sequence ACK. */
+	CC_DUPACK =	0x0002,	/* Duplicate ACK. */
+	CC_PARTIALACK =	0x0004,	/* Not yet. */
+	CC_SACK =	0x0008,	/* Not yet. */
+	/* Congestion signal types passed to the cong_signal() hook. */
+	CC_ECN =	0x0100,	/* ECN marked packet received. */
+	CC_RTO =	0x0200,	/* RTO fired. */
+	CC_RTO_ERR =	0x0400,	/* RTO fired in error. */
+	CC_NDUPACK =	0x0800,	/* Threshold of dupack's reached. */
+	/*
+	 * The highest order 8 bits (0x01000000 - 0x80000000) are reserved
+	 * for CC algos to declare their own congestion signal types.
+	 */
+	CC_SIGPRIVMASK = 0xFF000000	/* Mask to check if sig is private. */
+} ccsignal_t;
 #endif /* defined(_KERNEL) || defined(_WANT_TCPCB) */
 
-/*
- * Congestion signal types passed to the cong_signal() hook. The highest order 8
- * bits (0x01000000 - 0x80000000) are reserved for CC algos to declare their own
- * congestion signal types.
- */
-#define	CC_ECN		0x00000001	/* ECN marked packet received. */
-#define	CC_RTO		0x00000002	/* RTO fired. */
-#define	CC_RTO_ERR	0x00000004	/* RTO fired in error. */
-#define	CC_NDUPACK	0x00000008	/* Threshold of dupack's reached. */
-
-#define	CC_SIGPRIVMASK	0xFF000000	/* Mask to check if sig is private. */
-
 #ifdef _KERNEL
 /*
  * Structure to hold data and function pointers that together represent a
@@ -175,10 +175,10 @@
 	void	(*conn_init)(struct cc_var *ccv);
 
 	/* Called on receipt of an ack. */
-	void	(*ack_received)(struct cc_var *ccv, uint16_t type);
+	void	(*ack_received)(struct cc_var *ccv, ccsignal_t type);
 
 	/* Called on detection of a congestion signal. */
-	void	(*cong_signal)(struct cc_var *ccv, uint32_t type);
+	void	(*cong_signal)(struct cc_var *ccv, ccsignal_t type);
 
 	/* Called after exiting congestion recovery. */
 	void	(*post_recovery)(struct cc_var *ccv);
@@ -236,8 +236,8 @@
  */
 void newreno_cc_post_recovery(struct cc_var *);
 void newreno_cc_after_idle(struct cc_var *);
-void newreno_cc_cong_signal(struct cc_var *, uint32_t );
-void newreno_cc_ack_received(struct cc_var *, uint16_t);
+void newreno_cc_cong_signal(struct cc_var *, ccsignal_t);
+void newreno_cc_ack_received(struct cc_var *, ccsignal_t);
 
 /* Called to temporarily keep an algo from going away during change */
 void cc_refer(struct cc_algo *algo);
diff --git a/sys/netinet/cc/cc.c b/sys/netinet/cc/cc.c
--- a/sys/netinet/cc/cc.c
+++ b/sys/netinet/cc/cc.c
@@ -505,7 +505,7 @@
 }
 
 void
-newreno_cc_ack_received(struct cc_var *ccv, uint16_t type)
+newreno_cc_ack_received(struct cc_var *ccv, ccsignal_t type)
 {
 	if (type == CC_ACK && !IN_RECOVERY(CCV(ccv, t_flags)) &&
 	    (ccv->flags & CCF_CWND_LIMITED)) {
diff --git a/sys/netinet/cc/cc_cdg.c b/sys/netinet/cc/cc_cdg.c
--- a/sys/netinet/cc/cc_cdg.c
+++ b/sys/netinet/cc/cc_cdg.c
@@ -221,8 +221,8 @@
 static void cdg_conn_init(struct cc_var *ccv);
 static int cdg_cb_init(struct cc_var *ccv, void *ptr);
 static void cdg_cb_destroy(struct cc_var *ccv);
-static void cdg_cong_signal(struct cc_var *ccv, uint32_t signal_type);
-static void cdg_ack_received(struct cc_var *ccv, uint16_t ack_type);
+static void cdg_cong_signal(struct cc_var *ccv, ccsignal_t signal_type);
+static void cdg_ack_received(struct cc_var *ccv, ccsignal_t ack_type);
 static size_t cdg_data_sz(void);
 
 struct cc_algo cdg_cc_algo = {
@@ -450,11 +450,11 @@
 }
 
 static void
-cdg_cong_signal(struct cc_var *ccv, uint32_t signal_type)
+cdg_cong_signal(struct cc_var *ccv, ccsignal_t signal_type)
 {
 	struct cdg *cdg_data = ccv->cc_data;
 
-	switch(signal_type) {
+	switch((int)signal_type) {
 	case CC_CDG_DELAY:
 		CCV(ccv, snd_ssthresh) = cdg_window_decrease(ccv,
 		    CCV(ccv, snd_cwnd), V_cdg_beta_delay);
@@ -571,7 +571,7 @@
 }
 
 static void
-cdg_ack_received(struct cc_var *ccv, uint16_t ack_type)
+cdg_ack_received(struct cc_var *ccv, ccsignal_t ack_type)
 {
 	struct cdg *cdg_data;
 	struct ertt *e_t;
diff --git a/sys/netinet/cc/cc_chd.c b/sys/netinet/cc/cc_chd.c
--- a/sys/netinet/cc/cc_chd.c
+++ b/sys/netinet/cc/cc_chd.c
@@ -88,10 +88,10 @@
 /* Largest possible number returned by random(). */
 #define	RANDOM_MAX	INT_MAX
 
-static void	chd_ack_received(struct cc_var *ccv, uint16_t ack_type);
+static void	chd_ack_received(struct cc_var *ccv, ccsignal_t ack_type);
 static void	chd_cb_destroy(struct cc_var *ccv);
 static int	chd_cb_init(struct cc_var *ccv, void *ptr);
-static void	chd_cong_signal(struct cc_var *ccv, uint32_t signal_type);
+static void	chd_cong_signal(struct cc_var *ccv, ccsignal_t signal_type);
 static void	chd_conn_init(struct cc_var *ccv);
 static int	chd_mod_init(void);
 static size_t	chd_data_sz(void);
@@ -235,7 +235,7 @@
  * ack_type == CC_ACK.
  */
 static void
-chd_ack_received(struct cc_var *ccv, uint16_t ack_type)
+chd_ack_received(struct cc_var *ccv, ccsignal_t ack_type)
 {
 	struct chd *chd_data;
 	struct ertt *e_t;
@@ -336,7 +336,7 @@
 }
 
 static void
-chd_cong_signal(struct cc_var *ccv, uint32_t signal_type)
+chd_cong_signal(struct cc_var *ccv, ccsignal_t signal_type)
 {
 	struct ertt *e_t;
 	struct chd *chd_data;
@@ -346,7 +346,7 @@
 	chd_data = ccv->cc_data;
 	qdly = imax(e_t->rtt, chd_data->maxrtt_in_rtt) - e_t->minrtt;
 
-	switch(signal_type) {
+	switch((int)signal_type) {
 	case CC_CHD_DELAY:
 		chd_window_decrease(ccv); /* Set new ssthresh. */
 		CCV(ccv, snd_cwnd) = CCV(ccv, snd_ssthresh);
@@ -387,6 +387,7 @@
 
 	default:
 		newreno_cc_cong_signal(ccv, signal_type);
+		break;
 	}
 }
 
diff --git a/sys/netinet/cc/cc_cubic.c b/sys/netinet/cc/cc_cubic.c
--- a/sys/netinet/cc/cc_cubic.c
+++ b/sys/netinet/cc/cc_cubic.c
@@ -73,10 +73,10 @@
 #include <netinet/cc/cc_cubic.h>
 #include <netinet/cc/cc_module.h>
 
-static void	cubic_ack_received(struct cc_var *ccv, uint16_t type);
+static void	cubic_ack_received(struct cc_var *ccv, ccsignal_t type);
 static void	cubic_cb_destroy(struct cc_var *ccv);
 static int	cubic_cb_init(struct cc_var *ccv, void *ptr);
-static void	cubic_cong_signal(struct cc_var *ccv, uint32_t type);
+static void	cubic_cong_signal(struct cc_var *ccv, ccsignal_t type);
 static void	cubic_conn_init(struct cc_var *ccv);
 static int	cubic_mod_init(void);
 static void	cubic_post_recovery(struct cc_var *ccv);
@@ -233,7 +233,7 @@
 }
 
 static void
-cubic_ack_received(struct cc_var *ccv, uint16_t type)
+cubic_ack_received(struct cc_var *ccv, ccsignal_t type)
 {
 	struct cubic *cubic_data;
 	unsigned long W_est, W_cubic;
@@ -417,7 +417,7 @@
  * Perform any necessary tasks before we enter congestion recovery.
  */
 static void
-cubic_cong_signal(struct cc_var *ccv, uint32_t type)
+cubic_cong_signal(struct cc_var *ccv, ccsignal_t type)
 {
 	struct cubic *cubic_data;
 	uint32_t mss, pipe;
@@ -503,6 +503,8 @@
 		cubic_data->cwnd_epoch = cubic_data->undo_cwnd_epoch;
 		cubic_data->t_epoch = cubic_data->undo_t_epoch;
 		break;
+	default:
+		break;
 	}
 }
 
diff --git a/sys/netinet/cc/cc_dctcp.c b/sys/netinet/cc/cc_dctcp.c
--- a/sys/netinet/cc/cc_dctcp.c
+++ b/sys/netinet/cc/cc_dctcp.c
@@ -79,11 +79,11 @@
 	uint32_t num_cong_events; /* # of congestion events */
 };
 
-static void	dctcp_ack_received(struct cc_var *ccv, uint16_t type);
+static void	dctcp_ack_received(struct cc_var *ccv, ccsignal_t type);
 static void	dctcp_after_idle(struct cc_var *ccv);
 static void	dctcp_cb_destroy(struct cc_var *ccv);
 static int	dctcp_cb_init(struct cc_var *ccv, void *ptr);
-static void	dctcp_cong_signal(struct cc_var *ccv, uint32_t type);
+static void	dctcp_cong_signal(struct cc_var *ccv, ccsignal_t type);
 static void	dctcp_conn_init(struct cc_var *ccv);
 static void	dctcp_post_recovery(struct cc_var *ccv);
 static void	dctcp_ecnpkt_handler(struct cc_var *ccv);
@@ -104,7 +104,7 @@
 };
 
 static void
-dctcp_ack_received(struct cc_var *ccv, uint16_t type)
+dctcp_ack_received(struct cc_var *ccv, ccsignal_t type)
 {
 	struct dctcp *dctcp_data;
 	int bytes_acked = 0;
@@ -237,7 +237,7 @@
  * Perform any necessary tasks before we enter congestion recovery.
  */
 static void
-dctcp_cong_signal(struct cc_var *ccv, uint32_t type)
+dctcp_cong_signal(struct cc_var *ccv, ccsignal_t type)
 {
 	struct dctcp *dctcp_data;
 	uint32_t cwin, mss, pipe;
@@ -308,6 +308,8 @@
 			dctcp_data->save_sndnxt += CCV(ccv, t_maxseg);
 			dctcp_data->num_cong_events++;
 			break;
+		default:
+			break;
 		}
 	} else
 		newreno_cc_cong_signal(ccv, type);
diff --git a/sys/netinet/cc/cc_hd.c b/sys/netinet/cc/cc_hd.c
--- a/sys/netinet/cc/cc_hd.c
+++ b/sys/netinet/cc/cc_hd.c
@@ -80,7 +80,7 @@
 /* Largest possible number returned by random(). */
 #define	RANDOM_MAX	INT_MAX
 
-static void	hd_ack_received(struct cc_var *ccv, uint16_t ack_type);
+static void	hd_ack_received(struct cc_var *ccv, ccsignal_t ack_type);
 static int	hd_mod_init(void);
 static size_t	hd_data_sz(void);
 
@@ -138,7 +138,7 @@
  * as NewReno in all other circumstances.
  */
 static void
-hd_ack_received(struct cc_var *ccv, uint16_t ack_type)
+hd_ack_received(struct cc_var *ccv, ccsignal_t ack_type)
 {
 	struct ertt *e_t;
 	int qdly;
diff --git a/sys/netinet/cc/cc_htcp.c b/sys/netinet/cc/cc_htcp.c
--- a/sys/netinet/cc/cc_htcp.c
+++ b/sys/netinet/cc/cc_htcp.c
@@ -136,10 +136,10 @@
 	(((diff) / hz) * (((diff) << HTCP_ALPHA_INC_SHIFT) / (4 * hz))) \
 ) >> HTCP_ALPHA_INC_SHIFT)
 
-static void	htcp_ack_received(struct cc_var *ccv, uint16_t type);
+static void	htcp_ack_received(struct cc_var *ccv, ccsignal_t type);
 static void	htcp_cb_destroy(struct cc_var *ccv);
 static int	htcp_cb_init(struct cc_var *ccv, void *ptr);
-static void	htcp_cong_signal(struct cc_var *ccv, uint32_t type);
+static void	htcp_cong_signal(struct cc_var *ccv, ccsignal_t type);
 static int	htcp_mod_init(void);
 static void	htcp_post_recovery(struct cc_var *ccv);
 static void	htcp_recalc_alpha(struct cc_var *ccv);
@@ -190,7 +190,7 @@
 };
 
 static void
-htcp_ack_received(struct cc_var *ccv, uint16_t type)
+htcp_ack_received(struct cc_var *ccv, ccsignal_t type)
 {
 	struct htcp *htcp_data;
 
@@ -278,7 +278,7 @@
  * Perform any necessary tasks before we enter congestion recovery.
  */
 static void
-htcp_cong_signal(struct cc_var *ccv, uint32_t type)
+htcp_cong_signal(struct cc_var *ccv, ccsignal_t type)
 {
 	struct htcp *htcp_data;
 	uint32_t mss, pipe;
@@ -345,6 +345,8 @@
 		if (CCV(ccv, t_rxtshift) >= 2)
 			htcp_data->t_last_cong = ticks;
 		break;
+	default:
+		break;
 	}
 }
 
diff --git a/sys/netinet/cc/cc_newreno.c b/sys/netinet/cc/cc_newreno.c
--- a/sys/netinet/cc/cc_newreno.c
+++ b/sys/netinet/cc/cc_newreno.c
@@ -84,9 +84,9 @@
 #include <netinet/cc/cc_newreno.h>
 
 static void	newreno_cb_destroy(struct cc_var *ccv);
-static void	newreno_ack_received(struct cc_var *ccv, uint16_t type);
+static void	newreno_ack_received(struct cc_var *ccv, ccsignal_t type);
 static void	newreno_after_idle(struct cc_var *ccv);
-static void	newreno_cong_signal(struct cc_var *ccv, uint32_t type);
+static void	newreno_cong_signal(struct cc_var *ccv, ccsignal_t type);
 static int newreno_ctl_output(struct cc_var *ccv, struct sockopt *sopt, void *buf);
 static void	newreno_newround(struct cc_var *ccv, uint32_t round_cnt);
 static void	newreno_rttsample(struct cc_var *ccv, uint32_t usec_rtt, uint32_t rxtcnt, uint32_t fas);
@@ -212,7 +212,7 @@
 }
 
 static void
-newreno_ack_received(struct cc_var *ccv, uint16_t type)
+newreno_ack_received(struct cc_var *ccv, ccsignal_t type)
 {
 	struct newreno *nreno;
 
@@ -363,7 +363,7 @@
  * Perform any necessary tasks before we enter congestion recovery.
  */
 static void
-newreno_cong_signal(struct cc_var *ccv, uint32_t type)
+newreno_cong_signal(struct cc_var *ccv, ccsignal_t type)
 {
 	struct newreno *nreno;
 	uint32_t beta, beta_ecn, cwin, factor, mss, pipe;
@@ -442,6 +442,8 @@
 		}
 		CCV(ccv, snd_cwnd) = mss;
 		break;
+	default:
+		break;
 	}
 }
 
diff --git a/sys/netinet/cc/cc_vegas.c b/sys/netinet/cc/cc_vegas.c
--- a/sys/netinet/cc/cc_vegas.c
+++ b/sys/netinet/cc/cc_vegas.c
@@ -84,12 +84,12 @@
  * Private signal type for rate based congestion signal.
  * See <netinet/cc.h> for appropriate bit-range to use for private signals.
  */
-#define	CC_VEGAS_RATE	0x01000000
+#define	CC_VEGAS_RATE	0x04000000
 
-static void	vegas_ack_received(struct cc_var *ccv, uint16_t ack_type);
+static void	vegas_ack_received(struct cc_var *ccv, ccsignal_t ack_type);
 static void	vegas_cb_destroy(struct cc_var *ccv);
 static int	vegas_cb_init(struct cc_var *ccv, void *ptr);
-static void	vegas_cong_signal(struct cc_var *ccv, uint32_t signal_type);
+static void	vegas_cong_signal(struct cc_var *ccv, ccsignal_t signal_type);
 static void	vegas_conn_init(struct cc_var *ccv);
 static int	vegas_mod_init(void);
 static size_t	vegas_data_sz(void);
@@ -124,7 +124,7 @@
  * has been used.
  */
 static void
-vegas_ack_received(struct cc_var *ccv, uint16_t ack_type)
+vegas_ack_received(struct cc_var *ccv, ccsignal_t ack_type)
 {
 	struct ertt *e_t;
 	struct vegas *vegas_data;
@@ -203,7 +203,7 @@
  * handled here, otherwise it falls back to newreno's congestion handling.
  */
 static void
-vegas_cong_signal(struct cc_var *ccv, uint32_t signal_type)
+vegas_cong_signal(struct cc_var *ccv, ccsignal_t signal_type)
 {
 	struct vegas *vegas_data;
 	int presignalrecov;
@@ -215,7 +215,7 @@
 	else
 		presignalrecov = 0;
 
-	switch(signal_type) {
+	switch((int)signal_type) {
 	case CC_VEGAS_RATE:
 		if (!IN_RECOVERY(CCV(ccv, t_flags))) {
 			CCV(ccv, snd_cwnd) = max(2 * CCV(ccv, t_maxseg),
@@ -228,6 +228,7 @@
 
 	default:
 		newreno_cc_cong_signal(ccv, signal_type);
+		break;
 	}
 
 	if (IN_RECOVERY(CCV(ccv, t_flags)) && !presignalrecov)