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-rw-r--r--net/sctp/endpointola.c501
1 files changed, 501 insertions, 0 deletions
diff --git a/net/sctp/endpointola.c b/net/sctp/endpointola.c
new file mode 100644
index 000000000..9da76ba4d
--- /dev/null
+++ b/net/sctp/endpointola.c
@@ -0,0 +1,501 @@
+/* SCTP kernel implementation
+ * Copyright (c) 1999-2000 Cisco, Inc.
+ * Copyright (c) 1999-2001 Motorola, Inc.
+ * Copyright (c) 2001-2002 International Business Machines, Corp.
+ * Copyright (c) 2001 Intel Corp.
+ * Copyright (c) 2001 Nokia, Inc.
+ * Copyright (c) 2001 La Monte H.P. Yarroll
+ *
+ * This file is part of the SCTP kernel implementation
+ *
+ * This abstraction represents an SCTP endpoint.
+ *
+ * The SCTP implementation is free software;
+ * you can redistribute it and/or modify it under the terms of
+ * the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * The SCTP implementation is distributed in the hope that it
+ * will be useful, but WITHOUT ANY WARRANTY; without even the implied
+ * ************************
+ * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ * See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with GNU CC; see the file COPYING. If not, see
+ * <http://www.gnu.org/licenses/>.
+ *
+ * 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@austin.ibm.com>
+ * Daisy Chang <daisyc@us.ibm.com>
+ * Dajiang Zhang <dajiang.zhang@nokia.com>
+ */
+
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <linux/in.h>
+#include <linux/random.h> /* get_random_bytes() */
+#include <linux/crypto.h>
+#include <net/sock.h>
+#include <net/ipv6.h>
+#include <net/sctp/sctp.h>
+#include <net/sctp/sm.h>
+
+/* Forward declarations for internal helpers. */
+static void sctp_endpoint_bh_rcv(struct work_struct *work);
+
+/*
+ * Initialize the base fields of the endpoint structure.
+ */
+static struct sctp_endpoint *sctp_endpoint_init(struct sctp_endpoint *ep,
+ struct sock *sk,
+ gfp_t gfp)
+{
+ struct net *net = sock_net(sk);
+ struct sctp_hmac_algo_param *auth_hmacs = NULL;
+ struct sctp_chunks_param *auth_chunks = NULL;
+ struct sctp_shared_key *null_key;
+ int err;
+
+ ep->digest = kzalloc(SCTP_SIGNATURE_SIZE, gfp);
+ if (!ep->digest)
+ return NULL;
+
+ ep->auth_enable = net->sctp.auth_enable;
+ if (ep->auth_enable) {
+ /* Allocate space for HMACS and CHUNKS authentication
+ * variables. There are arrays that we encode directly
+ * into parameters to make the rest of the operations easier.
+ */
+ auth_hmacs = kzalloc(sizeof(sctp_hmac_algo_param_t) +
+ sizeof(__u16) * SCTP_AUTH_NUM_HMACS, gfp);
+ if (!auth_hmacs)
+ goto nomem;
+
+ auth_chunks = kzalloc(sizeof(sctp_chunks_param_t) +
+ SCTP_NUM_CHUNK_TYPES, gfp);
+ if (!auth_chunks)
+ goto nomem;
+
+ /* Initialize the HMACS parameter.
+ * SCTP-AUTH: Section 3.3
+ * Every endpoint supporting SCTP chunk authentication MUST
+ * support the HMAC based on the SHA-1 algorithm.
+ */
+ auth_hmacs->param_hdr.type = SCTP_PARAM_HMAC_ALGO;
+ auth_hmacs->param_hdr.length =
+ htons(sizeof(sctp_paramhdr_t) + 2);
+ auth_hmacs->hmac_ids[0] = htons(SCTP_AUTH_HMAC_ID_SHA1);
+
+ /* Initialize the CHUNKS parameter */
+ auth_chunks->param_hdr.type = SCTP_PARAM_CHUNKS;
+ auth_chunks->param_hdr.length = htons(sizeof(sctp_paramhdr_t));
+
+ /* If the Add-IP functionality is enabled, we must
+ * authenticate, ASCONF and ASCONF-ACK chunks
+ */
+ if (net->sctp.addip_enable) {
+ auth_chunks->chunks[0] = SCTP_CID_ASCONF;
+ auth_chunks->chunks[1] = SCTP_CID_ASCONF_ACK;
+ auth_chunks->param_hdr.length =
+ htons(sizeof(sctp_paramhdr_t) + 2);
+ }
+ }
+
+ /* Initialize the base structure. */
+ /* What type of endpoint are we? */
+ ep->base.type = SCTP_EP_TYPE_SOCKET;
+
+ /* Initialize the basic object fields. */
+ atomic_set(&ep->base.refcnt, 1);
+ ep->base.dead = false;
+
+ /* Create an input queue. */
+ sctp_inq_init(&ep->base.inqueue);
+
+ /* Set its top-half handler */
+ sctp_inq_set_th_handler(&ep->base.inqueue, sctp_endpoint_bh_rcv);
+
+ /* Initialize the bind addr area */
+ sctp_bind_addr_init(&ep->base.bind_addr, 0);
+
+ /* Remember who we are attached to. */
+ ep->base.sk = sk;
+ sock_hold(ep->base.sk);
+
+ /* Create the lists of associations. */
+ INIT_LIST_HEAD(&ep->asocs);
+
+ /* Use SCTP specific send buffer space queues. */
+ ep->sndbuf_policy = net->sctp.sndbuf_policy;
+
+ sk->sk_data_ready = sctp_data_ready;
+ sk->sk_write_space = sctp_write_space;
+ sock_set_flag(sk, SOCK_USE_WRITE_QUEUE);
+
+ /* Get the receive buffer policy for this endpoint */
+ ep->rcvbuf_policy = net->sctp.rcvbuf_policy;
+
+ /* Initialize the secret key used with cookie. */
+ get_random_bytes(ep->secret_key, sizeof(ep->secret_key));
+
+ /* SCTP-AUTH extensions*/
+ INIT_LIST_HEAD(&ep->endpoint_shared_keys);
+ null_key = sctp_auth_shkey_create(0, gfp);
+ if (!null_key)
+ goto nomem;
+
+ list_add(&null_key->key_list, &ep->endpoint_shared_keys);
+
+ /* Allocate and initialize transorms arrays for supported HMACs. */
+ err = sctp_auth_init_hmacs(ep, gfp);
+ if (err)
+ goto nomem_hmacs;
+
+ /* Add the null key to the endpoint shared keys list and
+ * set the hmcas and chunks pointers.
+ */
+ ep->auth_hmacs_list = auth_hmacs;
+ ep->auth_chunk_list = auth_chunks;
+
+ return ep;
+
+nomem_hmacs:
+ sctp_auth_destroy_keys(&ep->endpoint_shared_keys);
+nomem:
+ /* Free all allocations */
+ kfree(auth_hmacs);
+ kfree(auth_chunks);
+ kfree(ep->digest);
+ return NULL;
+
+}
+
+/* Create a sctp_endpoint with all that boring stuff initialized.
+ * Returns NULL if there isn't enough memory.
+ */
+struct sctp_endpoint *sctp_endpoint_new(struct sock *sk, gfp_t gfp)
+{
+ struct sctp_endpoint *ep;
+
+ /* Build a local endpoint. */
+ ep = kzalloc(sizeof(*ep), gfp);
+ if (!ep)
+ goto fail;
+
+ if (!sctp_endpoint_init(ep, sk, gfp))
+ goto fail_init;
+
+ SCTP_DBG_OBJCNT_INC(ep);
+ return ep;
+
+fail_init:
+ kfree(ep);
+fail:
+ return NULL;
+}
+
+/* Add an association to an endpoint. */
+void sctp_endpoint_add_asoc(struct sctp_endpoint *ep,
+ struct sctp_association *asoc)
+{
+ struct sock *sk = ep->base.sk;
+
+ /* If this is a temporary association, don't bother
+ * since we'll be removing it shortly and don't
+ * want anyone to find it anyway.
+ */
+ if (asoc->temp)
+ return;
+
+ /* Now just add it to our list of asocs */
+ list_add_tail(&asoc->asocs, &ep->asocs);
+
+ /* Increment the backlog value for a TCP-style listening socket. */
+ if (sctp_style(sk, TCP) && sctp_sstate(sk, LISTENING))
+ sk->sk_ack_backlog++;
+}
+
+/* Free the endpoint structure. Delay cleanup until
+ * all users have released their reference count on this structure.
+ */
+void sctp_endpoint_free(struct sctp_endpoint *ep)
+{
+ ep->base.dead = true;
+
+ ep->base.sk->sk_state = SCTP_SS_CLOSED;
+
+ /* Unlink this endpoint, so we can't find it again! */
+ sctp_unhash_endpoint(ep);
+
+ sctp_endpoint_put(ep);
+}
+
+/* Final destructor for endpoint. */
+static void sctp_endpoint_destroy(struct sctp_endpoint *ep)
+{
+ struct sock *sk;
+
+ if (unlikely(!ep->base.dead)) {
+ WARN(1, "Attempt to destroy undead endpoint %p!\n", ep);
+ return;
+ }
+
+ /* Free the digest buffer */
+ kfree(ep->digest);
+
+ /* SCTP-AUTH: Free up AUTH releated data such as shared keys
+ * chunks and hmacs arrays that were allocated
+ */
+ sctp_auth_destroy_keys(&ep->endpoint_shared_keys);
+ kfree(ep->auth_hmacs_list);
+ kfree(ep->auth_chunk_list);
+
+ /* AUTH - Free any allocated HMAC transform containers */
+ sctp_auth_destroy_hmacs(ep->auth_hmacs);
+
+ /* Cleanup. */
+ sctp_inq_free(&ep->base.inqueue);
+ sctp_bind_addr_free(&ep->base.bind_addr);
+
+ memset(ep->secret_key, 0, sizeof(ep->secret_key));
+
+ /* Give up our hold on the sock. */
+ sk = ep->base.sk;
+ if (sk != NULL) {
+ /* Remove and free the port */
+ if (sctp_sk(sk)->bind_hash)
+ sctp_put_port(sk);
+
+ sock_put(sk);
+ }
+
+ kfree(ep);
+ SCTP_DBG_OBJCNT_DEC(ep);
+}
+
+/* Hold a reference to an endpoint. */
+void sctp_endpoint_hold(struct sctp_endpoint *ep)
+{
+ atomic_inc(&ep->base.refcnt);
+}
+
+/* Release a reference to an endpoint and clean up if there are
+ * no more references.
+ */
+void sctp_endpoint_put(struct sctp_endpoint *ep)
+{
+ if (atomic_dec_and_test(&ep->base.refcnt))
+ sctp_endpoint_destroy(ep);
+}
+
+/* Is this the endpoint we are looking for? */
+struct sctp_endpoint *sctp_endpoint_is_match(struct sctp_endpoint *ep,
+ struct net *net,
+ const union sctp_addr *laddr)
+{
+ struct sctp_endpoint *retval = NULL;
+
+ if ((htons(ep->base.bind_addr.port) == laddr->v4.sin_port) &&
+ net_eq(sock_net(ep->base.sk), net)) {
+ if (sctp_bind_addr_match(&ep->base.bind_addr, laddr,
+ sctp_sk(ep->base.sk)))
+ retval = ep;
+ }
+
+ return retval;
+}
+
+/* Find the association that goes with this chunk.
+ * We do a linear search of the associations for this endpoint.
+ * We return the matching transport address too.
+ */
+static struct sctp_association *__sctp_endpoint_lookup_assoc(
+ const struct sctp_endpoint *ep,
+ const union sctp_addr *paddr,
+ struct sctp_transport **transport)
+{
+ struct sctp_association *asoc = NULL;
+ struct sctp_association *tmp;
+ struct sctp_transport *t = NULL;
+ struct sctp_hashbucket *head;
+ struct sctp_ep_common *epb;
+ int hash;
+ int rport;
+
+ *transport = NULL;
+
+ /* If the local port is not set, there can't be any associations
+ * on this endpoint.
+ */
+ if (!ep->base.bind_addr.port)
+ goto out;
+
+ rport = ntohs(paddr->v4.sin_port);
+
+ hash = sctp_assoc_hashfn(sock_net(ep->base.sk), ep->base.bind_addr.port,
+ rport);
+ head = &sctp_assoc_hashtable[hash];
+ read_lock(&head->lock);
+ sctp_for_each_hentry(epb, &head->chain) {
+ tmp = sctp_assoc(epb);
+ if (tmp->ep != ep || rport != tmp->peer.port)
+ continue;
+
+ t = sctp_assoc_lookup_paddr(tmp, paddr);
+ if (t) {
+ asoc = tmp;
+ *transport = t;
+ break;
+ }
+ }
+ read_unlock(&head->lock);
+out:
+ return asoc;
+}
+
+/* Lookup association on an endpoint based on a peer address. BH-safe. */
+struct sctp_association *sctp_endpoint_lookup_assoc(
+ const struct sctp_endpoint *ep,
+ const union sctp_addr *paddr,
+ struct sctp_transport **transport)
+{
+ struct sctp_association *asoc;
+
+ local_bh_disable();
+ asoc = __sctp_endpoint_lookup_assoc(ep, paddr, transport);
+ local_bh_enable();
+
+ return asoc;
+}
+
+/* Look for any peeled off association from the endpoint that matches the
+ * given peer address.
+ */
+int sctp_endpoint_is_peeled_off(struct sctp_endpoint *ep,
+ const union sctp_addr *paddr)
+{
+ struct sctp_sockaddr_entry *addr;
+ struct sctp_bind_addr *bp;
+ struct net *net = sock_net(ep->base.sk);
+
+ bp = &ep->base.bind_addr;
+ /* This function is called with the socket lock held,
+ * so the address_list can not change.
+ */
+ list_for_each_entry(addr, &bp->address_list, list) {
+ if (sctp_has_association(net, &addr->a, paddr))
+ return 1;
+ }
+
+ return 0;
+}
+
+/* Do delayed input processing. This is scheduled by sctp_rcv().
+ * This may be called on BH or task time.
+ */
+static void sctp_endpoint_bh_rcv(struct work_struct *work)
+{
+ struct sctp_endpoint *ep =
+ container_of(work, struct sctp_endpoint,
+ base.inqueue.immediate);
+ struct sctp_association *asoc;
+ struct sock *sk;
+ struct net *net;
+ struct sctp_transport *transport;
+ struct sctp_chunk *chunk;
+ struct sctp_inq *inqueue;
+ sctp_subtype_t subtype;
+ sctp_state_t state;
+ int error = 0;
+ int first_time = 1; /* is this the first time through the loop */
+
+ if (ep->base.dead)
+ return;
+
+ asoc = NULL;
+ inqueue = &ep->base.inqueue;
+ sk = ep->base.sk;
+ net = sock_net(sk);
+
+ while (NULL != (chunk = sctp_inq_pop(inqueue))) {
+ subtype = SCTP_ST_CHUNK(chunk->chunk_hdr->type);
+
+ /* If the first chunk in the packet is AUTH, do special
+ * processing specified in Section 6.3 of SCTP-AUTH spec
+ */
+ if (first_time && (subtype.chunk == SCTP_CID_AUTH)) {
+ struct sctp_chunkhdr *next_hdr;
+
+ next_hdr = sctp_inq_peek(inqueue);
+ if (!next_hdr)
+ goto normal;
+
+ /* If the next chunk is COOKIE-ECHO, skip the AUTH
+ * chunk while saving a pointer to it so we can do
+ * Authentication later (during cookie-echo
+ * processing).
+ */
+ if (next_hdr->type == SCTP_CID_COOKIE_ECHO) {
+ chunk->auth_chunk = skb_clone(chunk->skb,
+ GFP_ATOMIC);
+ chunk->auth = 1;
+ continue;
+ }
+ }
+normal:
+ /* We might have grown an association since last we
+ * looked, so try again.
+ *
+ * This happens when we've just processed our
+ * COOKIE-ECHO chunk.
+ */
+ if (NULL == chunk->asoc) {
+ asoc = sctp_endpoint_lookup_assoc(ep,
+ sctp_source(chunk),
+ &transport);
+ chunk->asoc = asoc;
+ chunk->transport = transport;
+ }
+
+ state = asoc ? asoc->state : SCTP_STATE_CLOSED;
+ if (sctp_auth_recv_cid(subtype.chunk, asoc) && !chunk->auth)
+ continue;
+
+ /* Remember where the last DATA chunk came from so we
+ * know where to send the SACK.
+ */
+ if (asoc && sctp_chunk_is_data(chunk))
+ asoc->peer.last_data_from = chunk->transport;
+ else {
+ SCTP_INC_STATS(sock_net(ep->base.sk), SCTP_MIB_INCTRLCHUNKS);
+ if (asoc)
+ asoc->stats.ictrlchunks++;
+ }
+
+ if (chunk->transport)
+ chunk->transport->last_time_heard = ktime_get();
+
+ error = sctp_do_sm(net, SCTP_EVENT_T_CHUNK, subtype, state,
+ ep, asoc, chunk, GFP_ATOMIC);
+
+ if (error && chunk)
+ chunk->pdiscard = 1;
+
+ /* Check to see if the endpoint is freed in response to
+ * the incoming chunk. If so, get out of the while loop.
+ */
+ if (!sctp_sk(sk)->ep)
+ break;
+
+ if (first_time)
+ first_time = 0;
+ }
+}
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