dccp_sync_mss(sk, mtu);
/*
- * From: draft-ietf-dccp-spec-11.txt
+ * From RFC 4340, sec. 14.1:
*
* DCCP-Sync packets are the best choice for upward
* probing, since DCCP-Sync probes do not risk application
} /* else let the usual retransmit timer handle it */
}
-static void dccp_v4_reqsk_send_ack(struct sk_buff *rxskb,
- struct request_sock *req)
-{
- int err;
- struct dccp_hdr *rxdh = dccp_hdr(rxskb), *dh;
- const u32 dccp_hdr_ack_len = sizeof(struct dccp_hdr) +
- sizeof(struct dccp_hdr_ext) +
- sizeof(struct dccp_hdr_ack_bits);
- struct sk_buff *skb;
-
- if (((struct rtable *)rxskb->dst)->rt_type != RTN_LOCAL)
- return;
-
- skb = alloc_skb(dccp_v4_ctl_socket->sk->sk_prot->max_header, GFP_ATOMIC);
- if (skb == NULL)
- return;
-
- /* Reserve space for headers. */
- skb_reserve(skb, dccp_v4_ctl_socket->sk->sk_prot->max_header);
-
- skb->dst = dst_clone(rxskb->dst);
-
- skb->h.raw = skb_push(skb, dccp_hdr_ack_len);
- dh = dccp_hdr(skb);
- memset(dh, 0, dccp_hdr_ack_len);
-
- /* Build DCCP header and checksum it. */
- dh->dccph_type = DCCP_PKT_ACK;
- dh->dccph_sport = rxdh->dccph_dport;
- dh->dccph_dport = rxdh->dccph_sport;
- dh->dccph_doff = dccp_hdr_ack_len / 4;
- dh->dccph_x = 1;
-
- dccp_hdr_set_seq(dh, DCCP_SKB_CB(rxskb)->dccpd_ack_seq);
- dccp_hdr_set_ack(dccp_hdr_ack_bits(skb),
- DCCP_SKB_CB(rxskb)->dccpd_seq);
-
- bh_lock_sock(dccp_v4_ctl_socket->sk);
- err = ip_build_and_send_pkt(skb, dccp_v4_ctl_socket->sk,
- rxskb->nh.iph->daddr,
- rxskb->nh.iph->saddr, NULL);
- bh_unlock_sock(dccp_v4_ctl_socket->sk);
-
- if (err == NET_XMIT_CN || err == 0) {
- DCCP_INC_STATS_BH(DCCP_MIB_OUTSEGS);
- DCCP_INC_STATS_BH(DCCP_MIB_OUTRSTS);
- }
-}
-
-static int dccp_v4_send_response(struct sock *sk, struct request_sock *req,
- struct dst_entry *dst)
-{
- int err = -1;
- struct sk_buff *skb;
-
- /* First, grab a route. */
-
- if (dst == NULL && (dst = inet_csk_route_req(sk, req)) == NULL)
- goto out;
-
- skb = dccp_make_response(sk, dst, req);
- if (skb != NULL) {
- const struct inet_request_sock *ireq = inet_rsk(req);
- struct dccp_hdr *dh = dccp_hdr(skb);
-
- dh->dccph_checksum = dccp_v4_checksum(skb, ireq->loc_addr,
- ireq->rmt_addr);
- memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
- err = ip_build_and_send_pkt(skb, sk, ireq->loc_addr,
- ireq->rmt_addr,
- ireq->opt);
- if (err == NET_XMIT_CN)
- err = 0;
- }
-
-out:
- dst_release(dst);
- return err;
-}
-
/*
* This routine is called by the ICMP module when it gets some sort of error
* condition. If err < 0 then the socket should be closed and the error
}
if (sk->sk_state == DCCP_TIME_WAIT) {
- inet_twsk_put((struct inet_timewait_sock *)sk);
+ inet_twsk_put(inet_twsk(sk));
return;
}
dccp_hdr(skb)->dccph_sport);
}
-int dccp_v4_conn_request(struct sock *sk, struct sk_buff *skb)
-{
- struct inet_request_sock *ireq;
- struct dccp_sock dp;
- struct request_sock *req;
- struct dccp_request_sock *dreq;
- const __be32 saddr = skb->nh.iph->saddr;
- const __be32 daddr = skb->nh.iph->daddr;
- const __be32 service = dccp_hdr_request(skb)->dccph_req_service;
- struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb);
- __u8 reset_code = DCCP_RESET_CODE_TOO_BUSY;
-
- /* Never answer to DCCP_PKT_REQUESTs send to broadcast or multicast */
- if (((struct rtable *)skb->dst)->rt_flags &
- (RTCF_BROADCAST | RTCF_MULTICAST)) {
- reset_code = DCCP_RESET_CODE_NO_CONNECTION;
- goto drop;
- }
-
- if (dccp_bad_service_code(sk, service)) {
- reset_code = DCCP_RESET_CODE_BAD_SERVICE_CODE;
- goto drop;
- }
- /*
- * TW buckets are converted to open requests without
- * limitations, they conserve resources and peer is
- * evidently real one.
- */
- if (inet_csk_reqsk_queue_is_full(sk))
- goto drop;
-
- /*
- * Accept backlog is full. If we have already queued enough
- * of warm entries in syn queue, drop request. It is better than
- * clogging syn queue with openreqs with exponentially increasing
- * timeout.
- */
- if (sk_acceptq_is_full(sk) && inet_csk_reqsk_queue_young(sk) > 1)
- goto drop;
-
- req = reqsk_alloc(sk->sk_prot->rsk_prot);
- if (req == NULL)
- goto drop;
-
- if (dccp_parse_options(sk, skb))
- goto drop_and_free;
-
- dccp_openreq_init(req, &dp, skb);
-
- if (security_inet_conn_request(sk, skb, req))
- goto drop_and_free;
-
- ireq = inet_rsk(req);
- ireq->loc_addr = daddr;
- ireq->rmt_addr = saddr;
- req->rcv_wnd = dccp_feat_default_sequence_window;
- ireq->opt = NULL;
-
- /*
- * Step 3: Process LISTEN state
- *
- * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookie
- *
- * In fact we defer setting S.GSR, S.SWL, S.SWH to
- * dccp_create_openreq_child.
- */
- dreq = dccp_rsk(req);
- dreq->dreq_isr = dcb->dccpd_seq;
- dreq->dreq_iss = dccp_v4_init_sequence(sk, skb);
- dreq->dreq_service = service;
-
- if (dccp_v4_send_response(sk, req, NULL))
- goto drop_and_free;
-
- inet_csk_reqsk_queue_hash_add(sk, req, DCCP_TIMEOUT_INIT);
- return 0;
-
-drop_and_free:
- reqsk_free(req);
-drop:
- DCCP_INC_STATS_BH(DCCP_MIB_ATTEMPTFAILS);
- dcb->dccpd_reset_code = reset_code;
- return -1;
-}
-
-EXPORT_SYMBOL_GPL(dccp_v4_conn_request);
-
/*
* The three way handshake has completed - we got a valid ACK or DATAACK -
* now create the new socket.
bh_lock_sock(nsk);
return nsk;
}
- inet_twsk_put((struct inet_timewait_sock *)nsk);
+ inet_twsk_put(inet_twsk(nsk));
return NULL;
}
return &rt->u.dst;
}
+static int dccp_v4_send_response(struct sock *sk, struct request_sock *req,
+ struct dst_entry *dst)
+{
+ int err = -1;
+ struct sk_buff *skb;
+
+ /* First, grab a route. */
+
+ if (dst == NULL && (dst = inet_csk_route_req(sk, req)) == NULL)
+ goto out;
+
+ skb = dccp_make_response(sk, dst, req);
+ if (skb != NULL) {
+ const struct inet_request_sock *ireq = inet_rsk(req);
+ struct dccp_hdr *dh = dccp_hdr(skb);
+
+ dh->dccph_checksum = dccp_v4_checksum(skb, ireq->loc_addr,
+ ireq->rmt_addr);
+ memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
+ err = ip_build_and_send_pkt(skb, sk, ireq->loc_addr,
+ ireq->rmt_addr,
+ ireq->opt);
+ if (err == NET_XMIT_CN)
+ err = 0;
+ }
+
+out:
+ dst_release(dst);
+ return err;
+}
+
static void dccp_v4_ctl_send_reset(struct sk_buff *rxskb)
{
int err;
skb_reserve(skb, dccp_v4_ctl_socket->sk->sk_prot->max_header);
skb->dst = dst_clone(dst);
- skb->h.raw = skb_push(skb, dccp_hdr_reset_len);
- dh = dccp_hdr(skb);
- memset(dh, 0, dccp_hdr_reset_len);
+ dh = dccp_zeroed_hdr(skb, dccp_hdr_reset_len);
/* Build DCCP header and checksum it. */
dh->dccph_type = DCCP_PKT_RESET;
dccp_hdr_reset(skb)->dccph_reset_code =
DCCP_SKB_CB(rxskb)->dccpd_reset_code;
- /* See "8.3.1. Abnormal Termination" in draft-ietf-dccp-spec-11 */
+ /* See "8.3.1. Abnormal Termination" in RFC 4340 */
seqno = 0;
if (DCCP_SKB_CB(rxskb)->dccpd_ack_seq != DCCP_PKT_WITHOUT_ACK_SEQ)
dccp_set_seqno(&seqno, DCCP_SKB_CB(rxskb)->dccpd_ack_seq + 1);
dst_release(dst);
}
+static void dccp_v4_reqsk_destructor(struct request_sock *req)
+{
+ kfree(inet_rsk(req)->opt);
+}
+
+static struct request_sock_ops dccp_request_sock_ops __read_mostly = {
+ .family = PF_INET,
+ .obj_size = sizeof(struct dccp_request_sock),
+ .rtx_syn_ack = dccp_v4_send_response,
+ .send_ack = dccp_reqsk_send_ack,
+ .destructor = dccp_v4_reqsk_destructor,
+ .send_reset = dccp_v4_ctl_send_reset,
+};
+
+int dccp_v4_conn_request(struct sock *sk, struct sk_buff *skb)
+{
+ struct inet_request_sock *ireq;
+ struct request_sock *req;
+ struct dccp_request_sock *dreq;
+ const __be32 service = dccp_hdr_request(skb)->dccph_req_service;
+ struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb);
+ __u8 reset_code = DCCP_RESET_CODE_TOO_BUSY;
+
+ /* Never answer to DCCP_PKT_REQUESTs send to broadcast or multicast */
+ if (((struct rtable *)skb->dst)->rt_flags &
+ (RTCF_BROADCAST | RTCF_MULTICAST)) {
+ reset_code = DCCP_RESET_CODE_NO_CONNECTION;
+ goto drop;
+ }
+
+ if (dccp_bad_service_code(sk, service)) {
+ reset_code = DCCP_RESET_CODE_BAD_SERVICE_CODE;
+ goto drop;
+ }
+ /*
+ * TW buckets are converted to open requests without
+ * limitations, they conserve resources and peer is
+ * evidently real one.
+ */
+ if (inet_csk_reqsk_queue_is_full(sk))
+ goto drop;
+
+ /*
+ * Accept backlog is full. If we have already queued enough
+ * of warm entries in syn queue, drop request. It is better than
+ * clogging syn queue with openreqs with exponentially increasing
+ * timeout.
+ */
+ if (sk_acceptq_is_full(sk) && inet_csk_reqsk_queue_young(sk) > 1)
+ goto drop;
+
+ req = reqsk_alloc(&dccp_request_sock_ops);
+ if (req == NULL)
+ goto drop;
+
+ if (dccp_parse_options(sk, skb))
+ goto drop_and_free;
+
+ dccp_reqsk_init(req, skb);
+
+ if (security_inet_conn_request(sk, skb, req))
+ goto drop_and_free;
+
+ ireq = inet_rsk(req);
+ ireq->loc_addr = skb->nh.iph->daddr;
+ ireq->rmt_addr = skb->nh.iph->saddr;
+ req->rcv_wnd = dccp_feat_default_sequence_window;
+ ireq->opt = NULL;
+
+ /*
+ * Step 3: Process LISTEN state
+ *
+ * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookie
+ *
+ * In fact we defer setting S.GSR, S.SWL, S.SWH to
+ * dccp_create_openreq_child.
+ */
+ dreq = dccp_rsk(req);
+ dreq->dreq_isr = dcb->dccpd_seq;
+ dreq->dreq_iss = dccp_v4_init_sequence(sk, skb);
+ dreq->dreq_service = service;
+
+ if (dccp_v4_send_response(sk, req, NULL))
+ goto drop_and_free;
+
+ inet_csk_reqsk_queue_hash_add(sk, req, DCCP_TIMEOUT_INIT);
+ return 0;
+
+drop_and_free:
+ reqsk_free(req);
+drop:
+ DCCP_INC_STATS_BH(DCCP_MIB_ATTEMPTFAILS);
+ dcb->dccpd_reset_code = reset_code;
+ return -1;
+}
+
+EXPORT_SYMBOL_GPL(dccp_v4_conn_request);
+
int dccp_v4_do_rcv(struct sock *sk, struct sk_buff *skb)
{
struct dccp_hdr *dh = dccp_hdr(skb);
/*
* Step 3: Process LISTEN state
- * If S.state == LISTEN,
- * If P.type == Request or P contains a valid Init Cookie
- * option,
- * * Must scan the packet's options to check for an Init
- * Cookie. Only the Init Cookie is processed here,
- * however; other options are processed in Step 8. This
- * scan need only be performed if the endpoint uses Init
- * Cookies *
- * * Generate a new socket and switch to that socket *
- * Set S := new socket for this port pair
- * S.state = RESPOND
- * Choose S.ISS (initial seqno) or set from Init Cookie
- * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookie
- * Continue with S.state == RESPOND
- * * A Response packet will be generated in Step 11 *
- * Otherwise,
- * Generate Reset(No Connection) unless P.type == Reset
- * Drop packet and return
+ * If P.type == Request or P contains a valid Init Cookie option,
+ * (* Must scan the packet's options to check for Init
+ * Cookies. Only Init Cookies are processed here,
+ * however; other options are processed in Step 8. This
+ * scan need only be performed if the endpoint uses Init
+ * Cookies *)
+ * (* Generate a new socket and switch to that socket *)
+ * Set S := new socket for this port pair
+ * S.state = RESPOND
+ * Choose S.ISS (initial seqno) or set from Init Cookies
+ * Initialize S.GAR := S.ISS
+ * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookies
+ * Continue with S.state == RESPOND
+ * (* A Response packet will be generated in Step 11 *)
+ * Otherwise,
+ * Generate Reset(No Connection) unless P.type == Reset
+ * Drop packet and return
*
* NOTE: the check for the packet types is done in
* dccp_rcv_state_process
dccp_pr_debug_cat("\n");
} else {
DCCP_SKB_CB(skb)->dccpd_ack_seq = dccp_hdr_ack_seq(skb);
- dccp_pr_debug_cat(", ack=%llu\n",
- (unsigned long long)
+ dccp_pr_debug_cat(", ack=%llu\n", (unsigned long long)
DCCP_SKB_CB(skb)->dccpd_ack_seq);
}
/*
* Step 2:
* If no socket ...
- * Generate Reset(No Connection) unless P.type == Reset
- * Drop packet and return
*/
if (sk == NULL) {
dccp_pr_debug("failed to look up flow ID in table and "
* Generate Reset(No Connection) unless P.type == Reset
* Drop packet and return
*/
-
if (sk->sk_state == DCCP_TIME_WAIT) {
- dccp_pr_debug("sk->sk_state == DCCP_TIME_WAIT: "
- "do_time_wait\n");
- goto do_time_wait;
+ dccp_pr_debug("sk->sk_state == DCCP_TIME_WAIT: do_time_wait\n");
+ inet_twsk_put(inet_twsk(sk));
+ goto no_dccp_socket;
}
if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb))
goto discard_it;
/*
* Step 2:
+ * If no socket ...
* Generate Reset(No Connection) unless P.type == Reset
* Drop packet and return
*/
}
discard_it:
- /* Discard frame. */
kfree_skb(skb);
return 0;
discard_and_relse:
sock_put(sk);
goto discard_it;
-
-do_time_wait:
- inet_twsk_put((struct inet_timewait_sock *)sk);
- goto no_dccp_socket;
}
static struct inet_connection_sock_af_ops dccp_ipv4_af_ops = {
return err;
}
-static void dccp_v4_reqsk_destructor(struct request_sock *req)
-{
- kfree(inet_rsk(req)->opt);
-}
-
-static struct request_sock_ops dccp_request_sock_ops = {
- .family = PF_INET,
- .obj_size = sizeof(struct dccp_request_sock),
- .rtx_syn_ack = dccp_v4_send_response,
- .send_ack = dccp_v4_reqsk_send_ack,
- .destructor = dccp_v4_reqsk_destructor,
- .send_reset = dccp_v4_ctl_send_reset,
-};
-
static struct timewait_sock_ops dccp_timewait_sock_ops = {
.twsk_obj_size = sizeof(struct inet_timewait_sock),
};