[SCTP] Last of the v4/v6 partioning (for now)

Mostly code on the bind path, splitting out to pf and af family
specific functions.   Minor code cleanups/fixes mixed in.  

include/net/sctp/sctp.h

@@ -123,8 +123,8 @@ extern sctp_protocol_t sctp_proto;
 extern struct sock *sctp_get_ctl_sock(void);
 extern int sctp_copy_local_addr_list(sctp_protocol_t *, sctp_bind_addr_t *,
 				     sctp_scope_t, int priority, int flags);
-extern sctp_pf_t *sctp_get_pf_specific(int family);
-extern void sctp_set_pf_specific(int family, sctp_pf_t *);
+extern struct sctp_pf *sctp_get_pf_specific(sa_family_t family);
+extern int sctp_register_pf(struct sctp_pf *, sa_family_t);
 
 /*
  * sctp_socket.c

include/net/sctp/structs.h

@@ -234,7 +234,7 @@ struct SCTP_protocol {
  * Pointers to address related SCTP functions.
  * (i.e. things that depend on the address family.)
  */
-typedef struct sctp_func {
+struct sctp_af {
 	int		(*queue_xmit)	(struct sk_buff *skb);
 	int 		(*setsockopt)	(struct sock *sk,
 					 int level,
@@ -259,27 +259,34 @@ typedef struct sctp_func {
 	void            (*from_skb)     (union sctp_addr *,
 					 struct sk_buff *skb,
 					 int saddr);
+	void            (*from_sk)      (union sctp_addr *,
+					 struct sock *sk);
+	void            (*to_sk)        (union sctp_addr *,
+					 struct sock *sk);
 	int             (*addr_valid)   (union sctp_addr *);
 	sctp_scope_t    (*scope) (union sctp_addr *);
 	void            (*inaddr_any)   (union sctp_addr *, unsigned short);
 	int             (*is_any)       (const union sctp_addr *);
+	int             (*available)    (const union sctp_addr *);
 	__u16		net_header_len;
 	int		sockaddr_len;
 	sa_family_t	sa_family;
 	struct list_head list;
-} sctp_func_t;
+};
 
-sctp_func_t *sctp_get_af_specific(sa_family_t);
+struct sctp_af *sctp_get_af_specific(sa_family_t);
+int sctp_register_af(struct sctp_af *);
 
 /* Protocol family functions. */
 typedef struct sctp_pf {
 	void (*event_msgname)(sctp_ulpevent_t *, char *, int *);
-	void (*skb_msgname)(struct sk_buff *, char *, int *);
-	int  (*af_supported)(sa_family_t);
+	void (*skb_msgname)  (struct sk_buff *, char *, int *);
+	int  (*af_supported) (sa_family_t);
 	int  (*cmp_addr) (const union sctp_addr *,
 			  const union sctp_addr *,
 			  struct sctp_opt *);
-	struct sctp_func *af;
+	int  (*bind_verify) (struct sctp_opt *, union sctp_addr *);
+	struct sctp_af *af;
 } sctp_pf_t;
 
 /* SCTP Socket type: UDP or TCP style. */
@@ -623,7 +630,7 @@ struct SCTP_transport {
 	union sctp_addr ipaddr;
 
 	/* These are the functions we call to handle LLP stuff.  */
-	sctp_func_t *af_specific;
+	struct sctp_af *af_specific;
 
 	/* Which association do we belong to?  */
 	sctp_association_t *asoc;

net/ipv6/ipv6_syms.c

@@ -24,3 +24,4 @@ EXPORT_SYMBOL(inet6_bind);
 EXPORT_SYMBOL(inet6_getname);
 EXPORT_SYMBOL(inet6_ioctl);
 EXPORT_SYMBOL(ipv6_get_saddr);
+EXPORT_SYMBOL(ipv6_chk_addr);

net/sctp/associola.c

@@ -642,7 +642,7 @@ __u16 __sctp_association_get_next_ssn(sctp_association_t *asoc, __u16 sid)
 int sctp_cmp_addr_exact(const union sctp_addr *ss1,
 			const union sctp_addr *ss2)
 {
-	struct sctp_func *af;
+	struct sctp_af *af;
 
 	af = sctp_get_af_specific(ss1->sa.sa_family);
 	if (!af)

net/sctp/bind_addr.c

@@ -327,7 +327,7 @@ static int sctp_copy_one_addr(sctp_bind_addr_t *dest, union sctp_addr *addr,
 /* Is this a wildcard address?  */
 int sctp_is_any(const union sctp_addr *addr)
 {
-	struct sctp_func *af = sctp_get_af_specific(addr->sa.sa_family);
+	struct sctp_af *af = sctp_get_af_specific(addr->sa.sa_family);
 	if (!af)
 		return 0;
 	return af->is_any(addr);
@@ -362,7 +362,7 @@ int sctp_in_scope(const union sctp_addr *addr, sctp_scope_t scope)
 /* What is the scope of 'addr'?  */
 sctp_scope_t sctp_scope(const union sctp_addr *addr)
 {
-	struct sctp_func *af;
+	struct sctp_af *af;
 
 	af = sctp_get_af_specific(addr->sa.sa_family);
 	if (!af)

net/sctp/input.c

@@ -96,7 +96,7 @@ int sctp_rcv(struct sk_buff *skb)
 	struct sctphdr *sh;
 	union sctp_addr src;
 	union sctp_addr dest;
-	struct sctp_func *af;
+	struct sctp_af *af;
 	int ret = 0;
 
 	if (skb->pkt_type!=PACKET_HOST)

net/sctp/ipv6.c

@@ -140,8 +140,8 @@ static inline int sctp_v6_xmit(struct sk_buff *skb)
 		 * to disallow loopback when the scoping rules have
 		 * not bound loopback to the endpoint.
 		 */
-		if (sctp_ipv6_addr_type(&saddr) & IPV6_ADDR_LOOPBACK) {
-			if (!(sctp_ipv6_addr_type(&np->daddr) &
+		if (ipv6_addr_type(&saddr) & IPV6_ADDR_LOOPBACK) {
+			if (!(ipv6_addr_type(&np->daddr) &
 			      IPV6_ADDR_LOOPBACK)) {
 				ipv6_addr_copy(&saddr, &np->daddr);
 			}
@@ -261,6 +261,20 @@ static void sctp_v6_from_skb(union sctp_addr *addr,struct sk_buff *skb,
 	ipv6_addr_copy(&addr->v6.sin6_addr, from);
 }
 
+/* Initialize an sctp_addr from a socket. */
+static void sctp_v6_from_sk(union sctp_addr *addr, struct sock *sk)
+{
+	addr->v6.sin6_family = AF_INET6;
+	addr->v6.sin6_port = inet_sk(sk)->num;
+	addr->v6.sin6_addr = inet6_sk(sk)->rcv_saddr;
+}
+
+/* Initialize sk->rcv_saddr from sctp_addr. */
+static void sctp_v6_to_sk(union sctp_addr *addr, struct sock *sk)
+{
+	inet6_sk(sk)->rcv_saddr = addr->v6.sin6_addr;
+}
+
 /* Initialize a sctp_addr from a dst_entry. */
 static void sctp_v6_dst_saddr(union sctp_addr *addr, struct dst_entry *dst)
 {
@@ -270,7 +284,7 @@ static void sctp_v6_dst_saddr(union sctp_addr *addr, struct dst_entry *dst)
 }
 
 /* Compare addresses exactly.  Well.. almost exactly; ignore scope_id
- * for now.  FIXME.
+ * for now.  FIXME: v4-mapped-v6.
  */
 static int sctp_v6_cmp_addr(const union sctp_addr *addr1,
 			    const union sctp_addr *addr2)
@@ -300,6 +314,22 @@ static int sctp_v6_is_any(const union sctp_addr *addr)
 	return IPV6_ADDR_ANY == type;
 }
 
+/* Should this be available for binding?   */
+static int sctp_v6_available(const union sctp_addr *addr)
+{
+	int type;
+	struct in6_addr *in6 = (struct in6_addr *)&addr->v6.sin6_addr;
+
+	type = ipv6_addr_type(in6);
+	if (IPV6_ADDR_ANY == type)
+		return 1;
+	if (!(type & IPV6_ADDR_UNICAST))
+		return 0;
+
+	return ipv6_chk_addr(in6, NULL);
+}
+
+
 /* This function checks if the address is a valid address to be used for
  * SCTP.
  *
@@ -309,7 +339,7 @@ static int sctp_v6_is_any(const union sctp_addr *addr)
  */
 static int sctp_v6_addr_valid(union sctp_addr *addr)
 {
-	int ret = sctp_ipv6_addr_type(&addr->v6.sin6_addr);
+	int ret = ipv6_addr_type(&addr->v6.sin6_addr);
 
 	/* FIXME:  v4-mapped-v6 address support. */
 
@@ -448,7 +478,7 @@ static int sctp_inet6_cmp_addr(const union sctp_addr *addr1,
 			       const union sctp_addr *addr2,
 			       struct sctp_opt *opt)
 {
-	struct sctp_func *af1, *af2;
+	struct sctp_af *af1, *af2;
 
 	af1 = sctp_get_af_specific(addr1->sa.sa_family);
 	af2 = sctp_get_af_specific(addr2->sa.sa_family);
@@ -465,7 +495,21 @@ static int sctp_inet6_cmp_addr(const union sctp_addr *addr1,
 	return af1->cmp_addr(addr1, addr2);
 }
 
+/* Verify that the provided sockaddr looks bindable.   Common verification,
+ * has already been taken care of.
+ */
+static int sctp_inet6_bind_verify(struct sctp_opt *opt, union sctp_addr *addr)
+{
+	struct sctp_af *af;
 
+	/* ASSERT: address family has already been verified. */
+	if (addr->sa.sa_family != AF_INET6) {
+		af = sctp_get_af_specific(addr->sa.sa_family);
+	} else
+		af = opt->pf->af;
+
+	return af->available(addr);
+}
 
 static struct proto_ops inet6_seqpacket_ops = {
 	.family     = PF_INET6,
@@ -501,29 +545,33 @@ static struct inet6_protocol sctpv6_protocol = {
 	.err_handler  = sctp_v6_err,
 };
 
-static sctp_func_t sctp_ipv6_specific = {
+static struct sctp_af sctp_ipv6_specific = {
 	.queue_xmit      = sctp_v6_xmit,
 	.setsockopt    = ipv6_setsockopt,
 	.getsockopt      = ipv6_getsockopt,
 	.get_dst	 = sctp_v6_get_dst,
 	.copy_addrlist   = sctp_v6_copy_addrlist,
 	.from_skb        = sctp_v6_from_skb,
+	.from_sk         = sctp_v6_from_sk,
+	.to_sk           = sctp_v6_to_sk,
 	.dst_saddr       = sctp_v6_dst_saddr,
 	.cmp_addr        = sctp_v6_cmp_addr,
 	.scope           = sctp_v6_scope,
 	.addr_valid      = sctp_v6_addr_valid,
 	.inaddr_any      = sctp_v6_inaddr_any,
 	.is_any          = sctp_v6_is_any,
+	.available       = sctp_v6_available,
 	.net_header_len  = sizeof(struct ipv6hdr),
 	.sockaddr_len    = sizeof(struct sockaddr_in6),
 	.sa_family       = AF_INET6,
 };
 
-static sctp_pf_t sctp_pf_inet6_specific = {
+static struct sctp_pf sctp_pf_inet6_specific = {
 	.event_msgname = sctp_inet6_event_msgname,
 	.skb_msgname   = sctp_inet6_skb_msgname,
 	.af_supported  = sctp_inet6_af_supported,
 	.cmp_addr      = sctp_inet6_cmp_addr,
+	.bind_verify   = sctp_inet6_bind_verify,
 	.af            = &sctp_ipv6_specific,
 };
 
@@ -538,11 +586,10 @@ int sctp_v6_init(void)
 	inet6_register_protosw(&sctpv6_protosw);
 
 	/* Register the SCTP specfic PF_INET6 functions. */
-	sctp_set_pf_specific(PF_INET6, &sctp_pf_inet6_specific);
+	sctp_register_pf(&sctp_pf_inet6_specific, PF_INET6);
 
-	/* Fill in address family info.  */
-	INIT_LIST_HEAD(&sctp_ipv6_specific.list);
-	list_add_tail(&sctp_ipv6_specific.list, &sctp_proto.address_families);
+	/* Register the SCTP specfic AF_INET6 functions. */
+	sctp_register_af(&sctp_ipv6_specific);
 
 	return 0;
 }

net/sctp/protocol.c

@@ -67,8 +67,10 @@ struct sctp_mib sctp_statistics[NR_CPUS * 2];
  */
 static struct socket *sctp_ctl_socket;
 
-static sctp_pf_t *sctp_pf_inet6_specific;
-static sctp_pf_t *sctp_pf_inet_specific;
+static struct sctp_pf *sctp_pf_inet6_specific;
+static struct sctp_pf *sctp_pf_inet_specific;
+static struct sctp_af *sctp_af_v4_specific;
+static struct sctp_af *sctp_af_v6_specific;
 
 extern struct net_proto_family inet_family_ops;
 
@@ -140,12 +142,12 @@ static void __sctp_get_local_addr_list(sctp_protocol_t *proto)
 {
 	struct net_device *dev;
 	struct list_head *pos;
-	struct sctp_func *af;
+	struct sctp_af *af;
 
 	read_lock(&dev_base_lock);
 	for (dev = dev_base; dev; dev = dev->next) {
 		list_for_each(pos, &proto->address_families) {
-			af = list_entry(pos, sctp_func_t, list);
+			af = list_entry(pos, struct sctp_af, list);
 			af->copy_addrlist(&proto->local_addr_list, dev);
 		}
 	}
@@ -251,7 +253,6 @@ struct dst_entry *sctp_v4_get_dst(union sctp_addr *daddr,
 	return &rt->u.dst;
 }
 
-
 /* Initialize a sctp_addr from in incoming skb.  */
 static void sctp_v4_from_skb(union sctp_addr *addr, struct sk_buff *skb,
 			     int is_saddr)
@@ -274,6 +275,21 @@ static void sctp_v4_from_skb(union sctp_addr *addr, struct sk_buff *skb,
 	memcpy(&addr->v4.sin_addr.s_addr, from, sizeof(struct in_addr));
 }
 
+/* Initialize an sctp_addr from a socket. */
+static void sctp_v4_from_sk(union sctp_addr *addr, struct sock *sk)
+{
+	addr->v4.sin_family = AF_INET;
+	addr->v4.sin_port = inet_sk(sk)->num;
+	addr->v4.sin_addr.s_addr = inet_sk(sk)->rcv_saddr;
+}
+
+/* Initialize sk->rcv_saddr from sctp_addr. */
+static void sctp_v4_to_sk(union sctp_addr *addr, struct sock *sk)
+{
+	inet_sk(sk)->rcv_saddr = addr->v4.sin_addr.s_addr;
+}
+
+
 /* Initialize a sctp_addr from a dst_entry. */
 static void sctp_v4_dst_saddr(union sctp_addr *saddr, struct dst_entry *dst)
 {
@@ -311,7 +327,7 @@ static int sctp_v4_is_any(const union sctp_addr *addr)
 }
 
 /* This function checks if the address is a valid address to be used for
- * SCTP.
+ * SCTP binding.
  *
  * Output:
  * Return 0 - If the address is a non-unicast or an illegal address.
@@ -326,6 +342,18 @@ static int sctp_v4_addr_valid(union sctp_addr *addr)
 	return 1;
 }
 
+/* Should this be available for binding?   */
+static int sctp_v4_available(const union sctp_addr *addr)
+{
+	int ret = inet_addr_type(addr->v4.sin_addr.s_addr);
+	
+	/* FIXME: ip_nonlocal_bind sysctl support. */
+
+	if (addr->v4.sin_addr.s_addr != INADDR_ANY && ret != RTN_LOCAL)
+		return 0;
+	return 1;
+}
+
 /* Checking the loopback, private and other address scopes as defined in
  * RFC 1918.   The IPv4 scoping is based on the draft for SCTP IPv4
  * scoping <draft-stewart-tsvwg-sctp-ipv4-00.txt>.
@@ -405,29 +433,42 @@ int sctp_ctl_sock_init(void)
 	return 0;
 }
 
-/* Get the table of functions for manipulating a particular address
- * family.
- */
-sctp_func_t *sctp_get_af_specific(sa_family_t family)
+/* Register address family specific functions. */
+int sctp_register_af(struct sctp_af *af)
 {
-	struct list_head *pos;
-	sctp_protocol_t *proto = sctp_get_protocol();
-	struct sctp_func *retval, *af;
+	switch (af->sa_family) {
+	case AF_INET:
+		if (sctp_af_v4_specific)
+			return 0;
+		sctp_af_v4_specific =  sctp_af_v4_specific = af;
+		break;
+	case AF_INET6:
+		if (sctp_af_v6_specific)
+			return 0;
+		sctp_af_v6_specific =  sctp_af_v6_specific = af;
+		break;
+	default:
+		return 0;
+	}
 
-	retval = NULL;
+	INIT_LIST_HEAD(&af->list);
+	list_add_tail(&af->list, &sctp_proto.address_families);
+	return 1;
+}
 
-	/* Cycle through all AF specific functions looking for a
-	 * match.
+/* Get the table of functions for manipulating a particular address
+ * family.
  */
-	list_for_each(pos, &proto->address_families) {
-		af = list_entry(pos, sctp_func_t, list);
-		if (family == af->sa_family) {
-			retval = af;
-			break;
-		}
+struct sctp_af *sctp_get_af_specific(sa_family_t family)
+{
+	switch (family) {
+	case AF_INET:
+		return sctp_af_v4_specific;
+	case AF_INET6:
+		return sctp_af_v6_specific;
+	default:
+		return NULL;
 	}
-
-	return retval;
 }
 
 /* Common code to initialize a AF_INET msg_name. */
@@ -495,18 +536,25 @@ static int sctp_inet_cmp_addr(const union sctp_addr *addr1,
 	return 0;
 }
 
+/* Verify that provided sockaddr looks bindable.  Common verification has
+ * already been taken care of.
+ */
+static int sctp_inet_bind_verify(struct sctp_opt *opt, union sctp_addr *addr)
+{
+	return sctp_v4_available(addr);
+}
 
-struct sctp_func sctp_ipv4_specific;
+struct sctp_af sctp_ipv4_specific;
 
-static sctp_pf_t sctp_pf_inet = {
+static struct sctp_pf sctp_pf_inet = {
 	.event_msgname = sctp_inet_event_msgname,
 	.skb_msgname   = sctp_inet_skb_msgname,
 	.af_supported  = sctp_inet_af_supported,
 	.cmp_addr      = sctp_inet_cmp_addr,
+	.bind_verify   = sctp_inet_bind_verify,
 	.af            = &sctp_ipv4_specific,
 };
 
-
 /* Registration for netdev events.  */
 struct notifier_block sctp_netdev_notifier = {
 	.notifier_call = sctp_netdev_event,
@@ -551,25 +599,28 @@ static struct inet_protocol sctp_protocol = {
 };
 
 /* IPv4 address related functions.  */
-struct sctp_func sctp_ipv4_specific = {
+struct sctp_af sctp_ipv4_specific = {
 	.queue_xmit     = ip_queue_xmit,
 	.setsockopt     = ip_setsockopt,
 	.getsockopt     = ip_getsockopt,
 	.get_dst	= sctp_v4_get_dst,
 	.copy_addrlist  = sctp_v4_copy_addrlist,
 	.from_skb       = sctp_v4_from_skb,
+	.from_sk        = sctp_v4_from_sk,
+	.to_sk          = sctp_v4_to_sk,
 	.dst_saddr      = sctp_v4_dst_saddr,
 	.cmp_addr       = sctp_v4_cmp_addr,
 	.addr_valid     = sctp_v4_addr_valid,
 	.inaddr_any     = sctp_v4_inaddr_any,
 	.is_any         = sctp_v4_is_any,
+	.available      = sctp_v4_available,
 	.scope          = sctp_v4_scope,
 	.net_header_len = sizeof(struct iphdr),
 	.sockaddr_len   = sizeof(struct sockaddr_in),
 	.sa_family      = AF_INET,
 };
 
-sctp_pf_t *sctp_get_pf_specific(int family) {
+struct sctp_pf *sctp_get_pf_specific(sa_family_t family) {
 
 	switch (family) {
 	case PF_INET:
@@ -581,20 +632,24 @@ sctp_pf_t *sctp_get_pf_specific(int family) {
 	}
 }
 
-/* Set the PF specific function table.  */
-void sctp_set_pf_specific(int family, sctp_pf_t *pf)
+/* Register the PF specific function table.  */
+int sctp_register_pf(struct sctp_pf *pf, sa_family_t family)
 {
 	switch (family) {
 	case PF_INET:
+		if (sctp_pf_inet_specific)
+			return 0;
 		sctp_pf_inet_specific = pf;
 		break;
 	case PF_INET6:
+		if (sctp_pf_inet6_specific)
+			return 0;
 		sctp_pf_inet6_specific = pf;
 		break;
 	default:
-		BUG();
-		break;
+		return 0;
 	}
+	return 1;
 }
 
 /* Initialize the universe into something sensible.  */
@@ -617,7 +672,7 @@ int sctp_init(void)
 	sctp_dbg_objcnt_init();
 
 	/* Initialize the SCTP specific PF functions. */
-	sctp_set_pf_specific(PF_INET, &sctp_pf_inet);
+	sctp_register_pf(&sctp_pf_inet, PF_INET);
 	/*
 	 * 14. Suggested SCTP Protocol Parameter Values
 	 */
@@ -709,8 +764,7 @@ int sctp_init(void)
 	sctp_sysctl_register();
 
 	INIT_LIST_HEAD(&sctp_proto.address_families);
-	INIT_LIST_HEAD(&sctp_ipv4_specific.list);
-	list_add_tail(&sctp_ipv4_specific.list, &sctp_proto.address_families);
+	sctp_register_af(&sctp_ipv4_specific);
 
 	status = sctp_v6_init();
 	if (status)

net/sctp/transport.c

@@ -207,7 +207,7 @@ void sctp_transport_route(sctp_transport_t *transport, union sctp_addr *saddr,
 			  struct sctp_opt *opt)
 {
 	sctp_association_t *asoc = transport->asoc;
-	struct sctp_func *af = transport->af_specific;
+	struct sctp_af *af = transport->af_specific;
 	union sctp_addr *daddr = &transport->ipaddr;
 	sctp_bind_addr_t *bp;
 	rwlock_t *addr_lock;