A major overhaul of the CARP implementation. The ip_carp.c was started

from scratch, copying needed functionality from the old implemenation
on demand, with a thorough review of all code. The main change is that
interface layer has been removed from the CARP. Now redundant addresses
are configured exactly on the interfaces, they run on.

The CARP configuration itself is, as before, configured and read via
SIOCSVH/SIOCGVH ioctls. A new prefix created with SIOCAIFADDR or
SIOCAIFADDR_IN6 may now be configured to a particular virtual host id,
which makes the prefix redundant.

ifconfig(8) semantics has been changed too: now one doesn't need
to clone carpXX interface, he/she should directly configure a vhid
on a Ethernet interface.

To supply vhid data from the kernel to an application the getifaddrs(8)
function had been changed to pass ifam_data with each address. [1]

The new implementation definitely closes all PRs related to carp(4)
being an interface, and may close several others. It also allows
to run a single redundant IP per interface.

Big thanks to Bjoern Zeeb for his help with inet6 part of patch, for
idea on using ifam_data and for several rounds of reviewing!

PR:		kern/117000, kern/126945, kern/126714, kern/120130, kern/117448
Reviewed by:	bz
Submitted by:	bz [1]

1 files changed, 21 insertions, 16 deletions

diff --git a/sys/netinet/ip_carp.h b/sys/netinet/ip_carp.h
index 2f2b4f2..d8b82a8 100644
--- a/sys/netinet/ip_carp.h
+++ b/sys/netinet/ip_carp.h
@@ -126,10 +126,12 @@ struct carpstats {
  * Configuration structure for SIOCSVH SIOCGVH
  */
 struct carpreq {
+	int		carpr_count;
+	int		carpr_vhid;
+#define	CARP_MAXVHID	255
 	int		carpr_state;
 #define	CARP_STATES	"INIT", "BACKUP", "MASTER"
 #define	CARP_MAXSTATE	2
-	int		carpr_vhid;
 	int		carpr_advskew;
 	int		carpr_advbase;
 	unsigned char	carpr_key[CARP_KEY_LEN];
@@ -144,8 +146,7 @@ struct carpreq {
 #define	CARPCTL_PREEMPT		2	/* high-pri backup preemption mode */
 #define	CARPCTL_LOG		3	/* log bad packets */
 #define	CARPCTL_STATS		4	/* statistics (read-only) */
-#define	CARPCTL_ARPBALANCE	5	/* balance arp responses */
-#define	CARPCTL_MAXID		6
+#define	CARPCTL_MAXID		5
 
 #define	CARPCTL_NAMES { \
 	{ 0, 0 }, \
@@ -153,33 +154,37 @@ struct carpreq {
 	{ "preempt", CTLTYPE_INT }, \
 	{ "log", CTLTYPE_INT }, \
 	{ "stats", CTLTYPE_STRUCT }, \
-	{ "arpbalance", CTLTYPE_INT }, \
 }
 
 #ifdef _KERNEL
-void		 carp_carpdev_state(struct ifnet *);
-void		 carp_input (struct mbuf *, int);
-int		 carp6_input (struct mbuf **, int *, int);
-int		 carp_output (struct ifnet *, struct mbuf *, struct sockaddr *,
-		     struct rtentry *);
-int		 carp_iamatch (struct ifnet *, struct in_ifaddr *, struct in_addr *,
-		     u_int8_t **);
+int		carp_ioctl(struct ifreq *, u_long, struct thread *);
+int		carp_attach(struct ifaddr *, int);
+void		carp_detach(struct ifaddr *);
+void		carp_carpdev_state(struct ifnet *);
+void		carp_input (struct mbuf *, int);
+int		carp6_input (struct mbuf **, int *, int);
+int		carp_output (struct ifnet *, struct mbuf *, struct sockaddr *);
+int		carp_iamatch(struct ifaddr *, uint8_t **);
 struct ifaddr	*carp_iamatch6(struct ifnet *, struct in6_addr *);
 caddr_t		carp_macmatch6(struct ifnet *, struct mbuf *, const struct in6_addr *);
-struct	ifnet	*carp_forus (struct ifnet *, u_char *);
+int		carp_forus(struct ifnet *, u_char *);
 
 /* These are external networking stack hooks for CARP */
 /* net/if.c */
+extern int (*carp_ioctl_p)(struct ifreq *, u_long, struct thread *);
+extern int (*carp_attach_p)(struct ifaddr *, int);
+extern void (*carp_detach_p)(struct ifaddr *);
 extern void (*carp_linkstate_p)(struct ifnet *);
 /* net/if_bridge.c net/if_ethersubr.c */
-extern struct ifnet *(*carp_forus_p)(struct ifnet *, u_char *);
+extern int (*carp_forus_p)(struct ifnet *, u_char *);
 /* net/if_ethersubr.c */
 extern int (*carp_output_p)(struct ifnet *, struct mbuf *,
-    struct sockaddr *, struct rtentry *);
+    struct sockaddr *);
+/* net/rtsock.c */
+extern int (*carp_get_vhid_p)(struct ifaddr *);
 #ifdef INET
 /* netinet/if_ether.c */
-extern int (*carp_iamatch_p)(struct ifnet *, struct in_ifaddr *,
-    struct in_addr *, u_int8_t **);
+extern int (*carp_iamatch_p)(struct ifaddr *, uint8_t **);
 #endif
 #ifdef INET6
 /* netinet6/nd6_nbr.c */