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-rw-r--r--net/sctp/bind_addr.c575
1 files changed, 575 insertions, 0 deletions
diff --git a/net/sctp/bind_addr.c b/net/sctp/bind_addr.c
new file mode 100644
index 000000000..6b95d3ba8
--- /dev/null
+++ b/net/sctp/bind_addr.c
@@ -0,0 +1,575 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* SCTP kernel implementation
+ * (C) Copyright IBM Corp. 2001, 2003
+ * Copyright (c) Cisco 1999,2000
+ * Copyright (c) Motorola 1999,2000,2001
+ * Copyright (c) La Monte H.P. Yarroll 2001
+ *
+ * This file is part of the SCTP kernel implementation.
+ *
+ * A collection class to handle the storage of transport addresses.
+ *
+ * Please send any bug reports or fixes you make to the
+ * email address(es):
+ * lksctp developers <linux-sctp@vger.kernel.org>
+ *
+ * Written or modified by:
+ * La Monte H.P. Yarroll <piggy@acm.org>
+ * Karl Knutson <karl@athena.chicago.il.us>
+ * Jon Grimm <jgrimm@us.ibm.com>
+ * Daisy Chang <daisyc@us.ibm.com>
+ */
+
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/in.h>
+#include <net/sock.h>
+#include <net/ipv6.h>
+#include <net/if_inet6.h>
+#include <net/sctp/sctp.h>
+#include <net/sctp/sm.h>
+
+/* Forward declarations for internal helpers. */
+static int sctp_copy_one_addr(struct net *net, struct sctp_bind_addr *dest,
+ union sctp_addr *addr, enum sctp_scope scope,
+ gfp_t gfp, int flags);
+static void sctp_bind_addr_clean(struct sctp_bind_addr *);
+
+/* First Level Abstractions. */
+
+/* Copy 'src' to 'dest' taking 'scope' into account. Omit addresses
+ * in 'src' which have a broader scope than 'scope'.
+ */
+int sctp_bind_addr_copy(struct net *net, struct sctp_bind_addr *dest,
+ const struct sctp_bind_addr *src,
+ enum sctp_scope scope, gfp_t gfp,
+ int flags)
+{
+ struct sctp_sockaddr_entry *addr;
+ int error = 0;
+
+ /* All addresses share the same port. */
+ dest->port = src->port;
+
+ /* Extract the addresses which are relevant for this scope. */
+ list_for_each_entry(addr, &src->address_list, list) {
+ error = sctp_copy_one_addr(net, dest, &addr->a, scope,
+ gfp, flags);
+ if (error < 0)
+ goto out;
+ }
+
+ /* If there are no addresses matching the scope and
+ * this is global scope, try to get a link scope address, with
+ * the assumption that we must be sitting behind a NAT.
+ */
+ if (list_empty(&dest->address_list) && (SCTP_SCOPE_GLOBAL == scope)) {
+ list_for_each_entry(addr, &src->address_list, list) {
+ error = sctp_copy_one_addr(net, dest, &addr->a,
+ SCTP_SCOPE_LINK, gfp,
+ flags);
+ if (error < 0)
+ goto out;
+ }
+ }
+
+ /* If somehow no addresses were found that can be used with this
+ * scope, it's an error.
+ */
+ if (list_empty(&dest->address_list))
+ error = -ENETUNREACH;
+
+out:
+ if (error)
+ sctp_bind_addr_clean(dest);
+
+ return error;
+}
+
+/* Exactly duplicate the address lists. This is necessary when doing
+ * peer-offs and accepts. We don't want to put all the current system
+ * addresses into the endpoint. That's useless. But we do want duplicat
+ * the list of bound addresses that the older endpoint used.
+ */
+int sctp_bind_addr_dup(struct sctp_bind_addr *dest,
+ const struct sctp_bind_addr *src,
+ gfp_t gfp)
+{
+ struct sctp_sockaddr_entry *addr;
+ int error = 0;
+
+ /* All addresses share the same port. */
+ dest->port = src->port;
+
+ list_for_each_entry(addr, &src->address_list, list) {
+ error = sctp_add_bind_addr(dest, &addr->a, sizeof(addr->a),
+ 1, gfp);
+ if (error < 0)
+ break;
+ }
+
+ return error;
+}
+
+/* Initialize the SCTP_bind_addr structure for either an endpoint or
+ * an association.
+ */
+void sctp_bind_addr_init(struct sctp_bind_addr *bp, __u16 port)
+{
+ INIT_LIST_HEAD(&bp->address_list);
+ bp->port = port;
+}
+
+/* Dispose of the address list. */
+static void sctp_bind_addr_clean(struct sctp_bind_addr *bp)
+{
+ struct sctp_sockaddr_entry *addr, *temp;
+
+ /* Empty the bind address list. */
+ list_for_each_entry_safe(addr, temp, &bp->address_list, list) {
+ list_del_rcu(&addr->list);
+ kfree_rcu(addr, rcu);
+ SCTP_DBG_OBJCNT_DEC(addr);
+ }
+}
+
+/* Dispose of an SCTP_bind_addr structure */
+void sctp_bind_addr_free(struct sctp_bind_addr *bp)
+{
+ /* Empty the bind address list. */
+ sctp_bind_addr_clean(bp);
+}
+
+/* Add an address to the bind address list in the SCTP_bind_addr structure. */
+int sctp_add_bind_addr(struct sctp_bind_addr *bp, union sctp_addr *new,
+ int new_size, __u8 addr_state, gfp_t gfp)
+{
+ struct sctp_sockaddr_entry *addr;
+
+ /* Add the address to the bind address list. */
+ addr = kzalloc(sizeof(*addr), gfp);
+ if (!addr)
+ return -ENOMEM;
+
+ memcpy(&addr->a, new, min_t(size_t, sizeof(*new), new_size));
+
+ /* Fix up the port if it has not yet been set.
+ * Both v4 and v6 have the port at the same offset.
+ */
+ if (!addr->a.v4.sin_port)
+ addr->a.v4.sin_port = htons(bp->port);
+
+ addr->state = addr_state;
+ addr->valid = 1;
+
+ INIT_LIST_HEAD(&addr->list);
+
+ /* We always hold a socket lock when calling this function,
+ * and that acts as a writer synchronizing lock.
+ */
+ list_add_tail_rcu(&addr->list, &bp->address_list);
+ SCTP_DBG_OBJCNT_INC(addr);
+
+ return 0;
+}
+
+/* Delete an address from the bind address list in the SCTP_bind_addr
+ * structure.
+ */
+int sctp_del_bind_addr(struct sctp_bind_addr *bp, union sctp_addr *del_addr)
+{
+ struct sctp_sockaddr_entry *addr, *temp;
+ int found = 0;
+
+ /* We hold the socket lock when calling this function,
+ * and that acts as a writer synchronizing lock.
+ */
+ list_for_each_entry_safe(addr, temp, &bp->address_list, list) {
+ if (sctp_cmp_addr_exact(&addr->a, del_addr)) {
+ /* Found the exact match. */
+ found = 1;
+ addr->valid = 0;
+ list_del_rcu(&addr->list);
+ break;
+ }
+ }
+
+ if (found) {
+ kfree_rcu(addr, rcu);
+ SCTP_DBG_OBJCNT_DEC(addr);
+ return 0;
+ }
+
+ return -EINVAL;
+}
+
+/* Create a network byte-order representation of all the addresses
+ * formated as SCTP parameters.
+ *
+ * The second argument is the return value for the length.
+ */
+union sctp_params sctp_bind_addrs_to_raw(const struct sctp_bind_addr *bp,
+ int *addrs_len,
+ gfp_t gfp)
+{
+ union sctp_params addrparms;
+ union sctp_params retval;
+ int addrparms_len;
+ union sctp_addr_param rawaddr;
+ int len;
+ struct sctp_sockaddr_entry *addr;
+ struct list_head *pos;
+ struct sctp_af *af;
+
+ addrparms_len = 0;
+ len = 0;
+
+ /* Allocate enough memory at once. */
+ list_for_each(pos, &bp->address_list) {
+ len += sizeof(union sctp_addr_param);
+ }
+
+ /* Don't even bother embedding an address if there
+ * is only one.
+ */
+ if (len == sizeof(union sctp_addr_param)) {
+ retval.v = NULL;
+ goto end_raw;
+ }
+
+ retval.v = kmalloc(len, gfp);
+ if (!retval.v)
+ goto end_raw;
+
+ addrparms = retval;
+
+ list_for_each_entry(addr, &bp->address_list, list) {
+ af = sctp_get_af_specific(addr->a.v4.sin_family);
+ len = af->to_addr_param(&addr->a, &rawaddr);
+ memcpy(addrparms.v, &rawaddr, len);
+ addrparms.v += len;
+ addrparms_len += len;
+ }
+
+end_raw:
+ *addrs_len = addrparms_len;
+ return retval;
+}
+
+/*
+ * Create an address list out of the raw address list format (IPv4 and IPv6
+ * address parameters).
+ */
+int sctp_raw_to_bind_addrs(struct sctp_bind_addr *bp, __u8 *raw_addr_list,
+ int addrs_len, __u16 port, gfp_t gfp)
+{
+ union sctp_addr_param *rawaddr;
+ struct sctp_paramhdr *param;
+ union sctp_addr addr;
+ int retval = 0;
+ int len;
+ struct sctp_af *af;
+
+ /* Convert the raw address to standard address format */
+ while (addrs_len) {
+ param = (struct sctp_paramhdr *)raw_addr_list;
+ rawaddr = (union sctp_addr_param *)raw_addr_list;
+
+ af = sctp_get_af_specific(param_type2af(param->type));
+ if (unlikely(!af) ||
+ !af->from_addr_param(&addr, rawaddr, htons(port), 0)) {
+ retval = -EINVAL;
+ goto out_err;
+ }
+
+ if (sctp_bind_addr_state(bp, &addr) != -1)
+ goto next;
+ retval = sctp_add_bind_addr(bp, &addr, sizeof(addr),
+ SCTP_ADDR_SRC, gfp);
+ if (retval)
+ /* Can't finish building the list, clean up. */
+ goto out_err;
+
+next:
+ len = ntohs(param->length);
+ addrs_len -= len;
+ raw_addr_list += len;
+ }
+
+ return retval;
+
+out_err:
+ if (retval)
+ sctp_bind_addr_clean(bp);
+
+ return retval;
+}
+
+/********************************************************************
+ * 2nd Level Abstractions
+ ********************************************************************/
+
+/* Does this contain a specified address? Allow wildcarding. */
+int sctp_bind_addr_match(struct sctp_bind_addr *bp,
+ const union sctp_addr *addr,
+ struct sctp_sock *opt)
+{
+ struct sctp_sockaddr_entry *laddr;
+ int match = 0;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(laddr, &bp->address_list, list) {
+ if (!laddr->valid)
+ continue;
+ if (opt->pf->cmp_addr(&laddr->a, addr, opt)) {
+ match = 1;
+ break;
+ }
+ }
+ rcu_read_unlock();
+
+ return match;
+}
+
+int sctp_bind_addrs_check(struct sctp_sock *sp,
+ struct sctp_sock *sp2, int cnt2)
+{
+ struct sctp_bind_addr *bp2 = &sp2->ep->base.bind_addr;
+ struct sctp_bind_addr *bp = &sp->ep->base.bind_addr;
+ struct sctp_sockaddr_entry *laddr, *laddr2;
+ bool exist = false;
+ int cnt = 0;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(laddr, &bp->address_list, list) {
+ list_for_each_entry_rcu(laddr2, &bp2->address_list, list) {
+ if (sp->pf->af->cmp_addr(&laddr->a, &laddr2->a) &&
+ laddr->valid && laddr2->valid) {
+ exist = true;
+ goto next;
+ }
+ }
+ cnt = 0;
+ break;
+next:
+ cnt++;
+ }
+ rcu_read_unlock();
+
+ return (cnt == cnt2) ? 0 : (exist ? -EEXIST : 1);
+}
+
+/* Does the address 'addr' conflict with any addresses in
+ * the bp.
+ */
+int sctp_bind_addr_conflict(struct sctp_bind_addr *bp,
+ const union sctp_addr *addr,
+ struct sctp_sock *bp_sp,
+ struct sctp_sock *addr_sp)
+{
+ struct sctp_sockaddr_entry *laddr;
+ int conflict = 0;
+ struct sctp_sock *sp;
+
+ /* Pick the IPv6 socket as the basis of comparison
+ * since it's usually a superset of the IPv4.
+ * If there is no IPv6 socket, then default to bind_addr.
+ */
+ if (sctp_opt2sk(bp_sp)->sk_family == AF_INET6)
+ sp = bp_sp;
+ else if (sctp_opt2sk(addr_sp)->sk_family == AF_INET6)
+ sp = addr_sp;
+ else
+ sp = bp_sp;
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(laddr, &bp->address_list, list) {
+ if (!laddr->valid)
+ continue;
+
+ conflict = sp->pf->cmp_addr(&laddr->a, addr, sp);
+ if (conflict)
+ break;
+ }
+ rcu_read_unlock();
+
+ return conflict;
+}
+
+/* Get the state of the entry in the bind_addr_list */
+int sctp_bind_addr_state(const struct sctp_bind_addr *bp,
+ const union sctp_addr *addr)
+{
+ struct sctp_sockaddr_entry *laddr;
+ struct sctp_af *af;
+
+ af = sctp_get_af_specific(addr->sa.sa_family);
+ if (unlikely(!af))
+ return -1;
+
+ list_for_each_entry_rcu(laddr, &bp->address_list, list) {
+ if (!laddr->valid)
+ continue;
+ if (af->cmp_addr(&laddr->a, addr))
+ return laddr->state;
+ }
+
+ return -1;
+}
+
+/* Find the first address in the bind address list that is not present in
+ * the addrs packed array.
+ */
+union sctp_addr *sctp_find_unmatch_addr(struct sctp_bind_addr *bp,
+ const union sctp_addr *addrs,
+ int addrcnt,
+ struct sctp_sock *opt)
+{
+ struct sctp_sockaddr_entry *laddr;
+ union sctp_addr *addr;
+ void *addr_buf;
+ struct sctp_af *af;
+ int i;
+
+ /* This is only called sctp_send_asconf_del_ip() and we hold
+ * the socket lock in that code patch, so that address list
+ * can't change.
+ */
+ list_for_each_entry(laddr, &bp->address_list, list) {
+ addr_buf = (union sctp_addr *)addrs;
+ for (i = 0; i < addrcnt; i++) {
+ addr = addr_buf;
+ af = sctp_get_af_specific(addr->v4.sin_family);
+ if (!af)
+ break;
+
+ if (opt->pf->cmp_addr(&laddr->a, addr, opt))
+ break;
+
+ addr_buf += af->sockaddr_len;
+ }
+ if (i == addrcnt)
+ return &laddr->a;
+ }
+
+ return NULL;
+}
+
+/* Copy out addresses from the global local address list. */
+static int sctp_copy_one_addr(struct net *net, struct sctp_bind_addr *dest,
+ union sctp_addr *addr, enum sctp_scope scope,
+ gfp_t gfp, int flags)
+{
+ int error = 0;
+
+ if (sctp_is_any(NULL, addr)) {
+ error = sctp_copy_local_addr_list(net, dest, scope, gfp, flags);
+ } else if (sctp_in_scope(net, addr, scope)) {
+ /* Now that the address is in scope, check to see if
+ * the address type is supported by local sock as
+ * well as the remote peer.
+ */
+ if ((((AF_INET == addr->sa.sa_family) &&
+ (flags & SCTP_ADDR4_ALLOWED) &&
+ (flags & SCTP_ADDR4_PEERSUPP))) ||
+ (((AF_INET6 == addr->sa.sa_family) &&
+ (flags & SCTP_ADDR6_ALLOWED) &&
+ (flags & SCTP_ADDR6_PEERSUPP))))
+ error = sctp_add_bind_addr(dest, addr, sizeof(*addr),
+ SCTP_ADDR_SRC, gfp);
+ }
+
+ return error;
+}
+
+/* Is this a wildcard address? */
+int sctp_is_any(struct sock *sk, const union sctp_addr *addr)
+{
+ unsigned short fam = 0;
+ struct sctp_af *af;
+
+ /* Try to get the right address family */
+ if (addr->sa.sa_family != AF_UNSPEC)
+ fam = addr->sa.sa_family;
+ else if (sk)
+ fam = sk->sk_family;
+
+ af = sctp_get_af_specific(fam);
+ if (!af)
+ return 0;
+
+ return af->is_any(addr);
+}
+
+/* Is 'addr' valid for 'scope'? */
+int sctp_in_scope(struct net *net, const union sctp_addr *addr,
+ enum sctp_scope scope)
+{
+ enum sctp_scope addr_scope = sctp_scope(addr);
+
+ /* The unusable SCTP addresses will not be considered with
+ * any defined scopes.
+ */
+ if (SCTP_SCOPE_UNUSABLE == addr_scope)
+ return 0;
+ /*
+ * For INIT and INIT-ACK address list, let L be the level of
+ * requested destination address, sender and receiver
+ * SHOULD include all of its addresses with level greater
+ * than or equal to L.
+ *
+ * Address scoping can be selectively controlled via sysctl
+ * option
+ */
+ switch (net->sctp.scope_policy) {
+ case SCTP_SCOPE_POLICY_DISABLE:
+ return 1;
+ case SCTP_SCOPE_POLICY_ENABLE:
+ if (addr_scope <= scope)
+ return 1;
+ break;
+ case SCTP_SCOPE_POLICY_PRIVATE:
+ if (addr_scope <= scope || SCTP_SCOPE_PRIVATE == addr_scope)
+ return 1;
+ break;
+ case SCTP_SCOPE_POLICY_LINK:
+ if (addr_scope <= scope || SCTP_SCOPE_LINK == addr_scope)
+ return 1;
+ break;
+ default:
+ break;
+ }
+
+ return 0;
+}
+
+int sctp_is_ep_boundall(struct sock *sk)
+{
+ struct sctp_bind_addr *bp;
+ struct sctp_sockaddr_entry *addr;
+
+ bp = &sctp_sk(sk)->ep->base.bind_addr;
+ if (sctp_list_single_entry(&bp->address_list)) {
+ addr = list_entry(bp->address_list.next,
+ struct sctp_sockaddr_entry, list);
+ if (sctp_is_any(sk, &addr->a))
+ return 1;
+ }
+ return 0;
+}
+
+/********************************************************************
+ * 3rd Level Abstractions
+ ********************************************************************/
+
+/* What is the scope of 'addr'? */
+enum sctp_scope sctp_scope(const union sctp_addr *addr)
+{
+ struct sctp_af *af;
+
+ af = sctp_get_af_specific(addr->sa.sa_family);
+ if (!af)
+ return SCTP_SCOPE_UNUSABLE;
+
+ return af->scope((union sctp_addr *)addr);
+}