* 2 of the License, or (at your option) any later version.
*/
-#include <linux/config.h>
#include <linux/dccp.h>
#include <linux/icmp.h>
#include <linux/module.h>
#include <linux/random.h>
#include <net/icmp.h>
+#include <net/inet_common.h>
#include <net/inet_hashtables.h>
#include <net/inet_sock.h>
+#include <net/protocol.h>
#include <net/sock.h>
#include <net/timewait_sock.h>
#include <net/tcp_states.h>
#include "ackvec.h"
#include "ccid.h"
#include "dccp.h"
+#include "feat.h"
-struct inet_hashinfo __cacheline_aligned dccp_hashinfo = {
- .lhash_lock = RW_LOCK_UNLOCKED,
- .lhash_users = ATOMIC_INIT(0),
- .lhash_wait = __WAIT_QUEUE_HEAD_INITIALIZER(dccp_hashinfo.lhash_wait),
-};
-
-EXPORT_SYMBOL_GPL(dccp_hashinfo);
+/*
+ * This is the global socket data structure used for responding to
+ * the Out-of-the-blue (OOTB) packets. A control sock will be created
+ * for this socket at the initialization time.
+ */
+static struct socket *dccp_v4_ctl_socket;
static int dccp_v4_get_port(struct sock *sk, const unsigned short snum)
{
inet_csk_bind_conflict);
}
-static void dccp_v4_hash(struct sock *sk)
-{
- inet_hash(&dccp_hashinfo, sk);
-}
-
-void dccp_unhash(struct sock *sk)
-{
- inet_unhash(&dccp_hashinfo, sk);
-}
-
-EXPORT_SYMBOL_GPL(dccp_unhash);
-
int dccp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len)
{
struct inet_sock *inet = inet_sk(sk);
struct dccp_sock *dp = dccp_sk(sk);
const struct sockaddr_in *usin = (struct sockaddr_in *)uaddr;
struct rtable *rt;
- u32 daddr, nexthop;
+ __be32 daddr, nexthop;
int tmp;
int err;
dp->dccps_role = DCCP_ROLE_CLIENT;
- if (dccp_service_not_initialized(sk))
- return -EPROTO;
-
if (addr_len < sizeof(struct sockaddr_in))
return -EINVAL;
/* OK, now commit destination to socket. */
sk_setup_caps(sk, &rt->u.dst);
- dp->dccps_gar =
- dp->dccps_iss = secure_dccp_sequence_number(inet->saddr,
- inet->daddr,
- inet->sport,
- usin->sin_port);
- dccp_update_gss(sk, dp->dccps_iss);
-
+ dp->dccps_iss = secure_dccp_sequence_number(inet->saddr, inet->daddr,
+ inet->sport, inet->dport);
inet->id = dp->dccps_iss ^ jiffies;
err = dccp_connect(sk);
/* We don't check in the destentry if pmtu discovery is forbidden
* on this route. We just assume that no packet_to_big packets
* are send back when pmtu discovery is not active.
- * There is a small race when the user changes this flag in the
+ * There is a small race when the user changes this flag in the
* route, but I think that's acceptable.
*/
if ((dst = __sk_dst_check(sk, 0)) == NULL)
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_ctl_send_ack(struct sk_buff *rxskb)
-{
- int err;
- struct dccp_hdr *rxdh = dccp_hdr(rxskb), *dh;
- const int 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(MAX_DCCP_HEADER + 15, GFP_ATOMIC);
- if (skb == NULL)
- return;
-
- /* Reserve space for headers. */
- skb_reserve(skb, MAX_DCCP_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_ctl_socket->sk);
- err = ip_build_and_send_pkt(skb, dccp_ctl_socket->sk,
- rxskb->nh.iph->daddr,
- rxskb->nh.iph->saddr, NULL);
- bh_unlock_sock(dccp_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 void dccp_v4_reqsk_send_ack(struct sk_buff *skb,
- struct request_sock *req)
-{
- dccp_v4_ctl_send_ack(skb);
-}
-
-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);
-
- 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
* check at all. A more general error queue to queue errors for later handling
* is probably better.
*/
-void dccp_v4_err(struct sk_buff *skb, u32 info)
+static void dccp_v4_err(struct sk_buff *skb, u32 info)
{
const struct iphdr *iph = (struct iphdr *)skb->data;
const struct dccp_hdr *dh = (struct dccp_hdr *)(skb->data +
}
if (sk->sk_state == DCCP_TIME_WAIT) {
- inet_twsk_put((struct inet_timewait_sock *)sk);
+ inet_twsk_put(inet_twsk(sk));
return;
}
seq = dccp_hdr_seq(skb);
if (sk->sk_state != DCCP_LISTEN &&
!between48(seq, dp->dccps_swl, dp->dccps_swh)) {
- NET_INC_STATS(LINUX_MIB_OUTOFWINDOWICMPS);
+ NET_INC_STATS_BH(LINUX_MIB_OUTOFWINDOWICMPS);
goto out;
}
sock_put(sk);
}
-/* This routine computes an IPv4 DCCP checksum. */
-void dccp_v4_send_check(struct sock *sk, int len, struct sk_buff *skb)
+static inline __sum16 dccp_v4_csum_finish(struct sk_buff *skb,
+ __be32 src, __be32 dst)
+{
+ return csum_tcpudp_magic(src, dst, skb->len, IPPROTO_DCCP, skb->csum);
+}
+
+void dccp_v4_send_check(struct sock *sk, int unused, struct sk_buff *skb)
{
const struct inet_sock *inet = inet_sk(sk);
struct dccp_hdr *dh = dccp_hdr(skb);
- dh->dccph_checksum = dccp_v4_checksum(skb, inet->saddr, inet->daddr);
+ dccp_csum_outgoing(skb);
+ dh->dccph_checksum = dccp_v4_csum_finish(skb, inet->saddr, inet->daddr);
}
EXPORT_SYMBOL_GPL(dccp_v4_send_check);
-int dccp_v4_send_reset(struct sock *sk, enum dccp_reset_codes code)
-{
- struct sk_buff *skb;
- /*
- * FIXME: what if rebuild_header fails?
- * Should we be doing a rebuild_header here?
- */
- int err = inet_sk_rebuild_header(sk);
-
- if (err != 0)
- return err;
-
- skb = dccp_make_reset(sk, sk->sk_dst_cache, code);
- if (skb != NULL) {
- const struct inet_sock *inet = inet_sk(sk);
-
- memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
- err = ip_build_and_send_pkt(skb, sk,
- inet->saddr, inet->daddr, NULL);
- if (err == NET_XMIT_CN)
- err = 0;
- }
-
- return err;
-}
-
-static inline u64 dccp_v4_init_sequence(const struct sock *sk,
- const struct sk_buff *skb)
+static inline u64 dccp_v4_init_sequence(const struct sk_buff *skb)
{
return secure_dccp_sequence_number(skb->nh.iph->daddr,
skb->nh.iph->saddr,
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 __u32 saddr = skb->nh.iph->saddr;
- const __u32 daddr = skb->nh.iph->daddr;
- const __u32 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;
-
- /* FIXME: process options */
-
- dccp_openreq_init(req, &dp, skb);
-
- ireq = inet_rsk(req);
- ireq->loc_addr = daddr;
- ireq->rmt_addr = saddr;
- req->rcv_wnd = 100; /* Fake, option parsing will get the
- right value */
- 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.
if (req != NULL)
return dccp_check_req(sk, skb, req, prev);
- nsk = __inet_lookup_established(&dccp_hashinfo,
- iph->saddr, dh->dccph_sport,
- iph->daddr, ntohs(dh->dccph_dport),
- inet_iif(skb));
+ nsk = inet_lookup_established(&dccp_hashinfo,
+ iph->saddr, dh->dccph_sport,
+ iph->daddr, dh->dccph_dport,
+ inet_iif(skb));
if (nsk != NULL) {
if (nsk->sk_state != DCCP_TIME_WAIT) {
bh_lock_sock(nsk);
return nsk;
}
- inet_twsk_put((struct inet_timewait_sock *)nsk);
+ inet_twsk_put(inet_twsk(nsk));
return NULL;
}
return sk;
}
-int dccp_v4_checksum(const struct sk_buff *skb, const u32 saddr,
- const u32 daddr)
-{
- const struct dccp_hdr* dh = dccp_hdr(skb);
- int checksum_len;
- u32 tmp;
-
- if (dh->dccph_cscov == 0)
- checksum_len = skb->len;
- else {
- checksum_len = (dh->dccph_cscov + dh->dccph_x) * sizeof(u32);
- checksum_len = checksum_len < skb->len ? checksum_len :
- skb->len;
- }
-
- tmp = csum_partial((unsigned char *)dh, checksum_len, 0);
- return csum_tcpudp_magic(saddr, daddr, checksum_len,
- IPPROTO_DCCP, tmp);
-}
-
-static int dccp_v4_verify_checksum(struct sk_buff *skb,
- const u32 saddr, const u32 daddr)
-{
- struct dccp_hdr *dh = dccp_hdr(skb);
- int checksum_len;
- u32 tmp;
-
- if (dh->dccph_cscov == 0)
- checksum_len = skb->len;
- else {
- checksum_len = (dh->dccph_cscov + dh->dccph_x) * sizeof(u32);
- checksum_len = checksum_len < skb->len ? checksum_len :
- skb->len;
- }
- tmp = csum_partial((unsigned char *)dh, checksum_len, 0);
- return csum_tcpudp_magic(saddr, daddr, checksum_len,
- IPPROTO_DCCP, tmp) == 0 ? 0 : -1;
-}
-
static struct dst_entry* dccp_v4_route_skb(struct sock *sk,
struct sk_buff *skb)
{
.uli_u = { .ports =
{ .sport = dccp_hdr(skb)->dccph_dport,
.dport = dccp_hdr(skb)->dccph_sport }
- }
+ }
};
+ security_skb_classify_flow(skb, &fl);
if (ip_route_output_flow(&rt, &fl, sk, 0)) {
IP_INC_STATS_BH(IPSTATS_MIB_OUTNOROUTES);
return NULL;
return &rt->u.dst;
}
-static void dccp_v4_ctl_send_reset(struct sk_buff *rxskb)
+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_csum_finish(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);
+ err = net_xmit_eval(err);
+ }
+
+out:
+ dst_release(dst);
+ return err;
+}
+
+static void dccp_v4_ctl_send_reset(struct sock *sk, struct sk_buff *rxskb)
{
int err;
struct dccp_hdr *rxdh = dccp_hdr(rxskb), *dh;
sizeof(struct dccp_hdr_reset);
struct sk_buff *skb;
struct dst_entry *dst;
- u64 seqno;
+ u64 seqno = 0;
/* Never send a reset in response to a reset. */
if (rxdh->dccph_type == DCCP_PKT_RESET)
if (((struct rtable *)rxskb->dst)->rt_type != RTN_LOCAL)
return;
- dst = dccp_v4_route_skb(dccp_ctl_socket->sk, rxskb);
+ dst = dccp_v4_route_skb(dccp_v4_ctl_socket->sk, rxskb);
if (dst == NULL)
return;
- skb = alloc_skb(MAX_DCCP_HEADER + 15, GFP_ATOMIC);
+ skb = alloc_skb(dccp_v4_ctl_socket->sk->sk_prot->max_header,
+ GFP_ATOMIC);
if (skb == NULL)
goto out;
/* Reserve space for headers. */
- skb_reserve(skb, MAX_DCCP_HEADER);
+ 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 */
- seqno = 0;
+ /* See "8.3.1. Abnormal Termination" in RFC 4340 */
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);
dccp_hdr_set_seq(dh, seqno);
- dccp_hdr_set_ack(dccp_hdr_ack_bits(skb),
- DCCP_SKB_CB(rxskb)->dccpd_seq);
+ dccp_hdr_set_ack(dccp_hdr_ack_bits(skb), DCCP_SKB_CB(rxskb)->dccpd_seq);
- dh->dccph_checksum = dccp_v4_checksum(skb, rxskb->nh.iph->saddr,
- rxskb->nh.iph->daddr);
+ dccp_csum_outgoing(skb);
+ dh->dccph_checksum = dccp_v4_csum_finish(skb, rxskb->nh.iph->saddr,
+ rxskb->nh.iph->daddr);
- bh_lock_sock(dccp_ctl_socket->sk);
- err = ip_build_and_send_pkt(skb, dccp_ctl_socket->sk,
+ 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_ctl_socket->sk);
+ bh_unlock_sock(dccp_v4_ctl_socket->sk);
- if (err == NET_XMIT_CN || err == 0) {
+ if (net_xmit_eval(err) == 0) {
DCCP_INC_STATS_BH(DCCP_MIB_OUTSEGS);
DCCP_INC_STATS_BH(DCCP_MIB_OUTRSTS);
}
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;
+ 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(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
return 0;
reset:
- dccp_v4_ctl_send_reset(skb);
+ dccp_v4_ctl_send_reset(sk, skb);
discard:
kfree_skb(skb);
return 0;
EXPORT_SYMBOL_GPL(dccp_v4_do_rcv);
+/**
+ * dccp_invalid_packet - check for malformed packets
+ * Implements RFC 4340, 8.5: Step 1: Check header basics
+ * Packets that fail these checks are ignored and do not receive Resets.
+ */
int dccp_invalid_packet(struct sk_buff *skb)
{
const struct dccp_hdr *dh;
+ unsigned int cscov;
if (skb->pkt_type != PACKET_HOST)
return 1;
+ /* If the packet is shorter than 12 bytes, drop packet and return */
if (!pskb_may_pull(skb, sizeof(struct dccp_hdr))) {
- LIMIT_NETDEBUG(KERN_WARNING "DCCP: pskb_may_pull failed\n");
+ DCCP_WARN("pskb_may_pull failed\n");
return 1;
}
dh = dccp_hdr(skb);
- /* If the packet type is not understood, drop packet and return */
+ /* If P.type is not understood, drop packet and return */
if (dh->dccph_type >= DCCP_PKT_INVALID) {
- LIMIT_NETDEBUG(KERN_WARNING "DCCP: invalid packet type\n");
+ DCCP_WARN("invalid packet type\n");
return 1;
}
/*
- * If P.Data Offset is too small for packet type, or too large for
- * packet, drop packet and return
+ * If P.Data Offset is too small for packet type, drop packet and return
*/
if (dh->dccph_doff < dccp_hdr_len(skb) / sizeof(u32)) {
- LIMIT_NETDEBUG(KERN_WARNING "DCCP: P.Data Offset(%u) "
- "too small 1\n",
- dh->dccph_doff);
+ DCCP_WARN("P.Data Offset(%u) too small\n", dh->dccph_doff);
return 1;
}
-
+ /*
+ * If P.Data Offset is too too large for packet, drop packet and return
+ */
if (!pskb_may_pull(skb, dh->dccph_doff * sizeof(u32))) {
- LIMIT_NETDEBUG(KERN_WARNING "DCCP: P.Data Offset(%u) "
- "too small 2\n",
- dh->dccph_doff);
+ DCCP_WARN("P.Data Offset(%u) too large\n", dh->dccph_doff);
return 1;
}
- dh = dccp_hdr(skb);
-
/*
* If P.type is not Data, Ack, or DataAck and P.X == 0 (the packet
* has short sequence numbers), drop packet and return
*/
- if (dh->dccph_x == 0 &&
- dh->dccph_type != DCCP_PKT_DATA &&
- dh->dccph_type != DCCP_PKT_ACK &&
- dh->dccph_type != DCCP_PKT_DATAACK) {
- LIMIT_NETDEBUG(KERN_WARNING "DCCP: P.type (%s) not Data, Ack "
- "nor DataAck and P.X == 0\n",
- dccp_packet_name(dh->dccph_type));
+ if (dh->dccph_type >= DCCP_PKT_DATA &&
+ dh->dccph_type <= DCCP_PKT_DATAACK && dh->dccph_x == 0) {
+ DCCP_WARN("P.type (%s) not Data || [Data]Ack, while P.X == 0\n",
+ dccp_packet_name(dh->dccph_type));
return 1;
}
+ /*
+ * If P.CsCov is too large for the packet size, drop packet and return.
+ * This must come _before_ checksumming (not as RFC 4340 suggests).
+ */
+ cscov = dccp_csum_coverage(skb);
+ if (cscov > skb->len) {
+ DCCP_WARN("P.CsCov %u exceeds packet length %d\n",
+ dh->dccph_cscov, skb->len);
+ return 1;
+ }
+
+ /* If header checksum is incorrect, drop packet and return.
+ * (This step is completed in the AF-dependent functions.) */
+ skb->csum = skb_checksum(skb, 0, cscov, 0);
+
return 0;
}
EXPORT_SYMBOL_GPL(dccp_invalid_packet);
/* this is called when real data arrives */
-int dccp_v4_rcv(struct sk_buff *skb)
+static int dccp_v4_rcv(struct sk_buff *skb)
{
const struct dccp_hdr *dh;
struct sock *sk;
+ int min_cov;
- /* Step 1: Check header basics: */
+ /* Step 1: Check header basics */
if (dccp_invalid_packet(skb))
goto discard_it;
- /* If the header checksum is incorrect, drop packet and return */
- if (dccp_v4_verify_checksum(skb, skb->nh.iph->saddr,
- skb->nh.iph->daddr) < 0) {
- LIMIT_NETDEBUG(KERN_WARNING "%s: incorrect header checksum\n",
- __FUNCTION__);
+ /* Step 1: If header checksum is incorrect, drop packet and return */
+ if (dccp_v4_csum_finish(skb, skb->nh.iph->saddr, skb->nh.iph->daddr)) {
+ DCCP_WARN("dropped packet with invalid checksum\n");
goto discard_it;
}
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:
- * Look up flow ID in table and get corresponding socket */
+ * Look up flow ID in table and get corresponding socket */
sk = __inet_lookup(&dccp_hashinfo,
skb->nh.iph->saddr, dh->dccph_sport,
- skb->nh.iph->daddr, ntohs(dh->dccph_dport),
+ skb->nh.iph->daddr, dh->dccph_dport,
inet_iif(skb));
- /*
+ /*
* Step 2:
- * If no socket ...
- * Generate Reset(No Connection) unless P.type == Reset
- * Drop packet and return
+ * If no socket ...
*/
if (sk == NULL) {
dccp_pr_debug("failed to look up flow ID in table and "
goto no_dccp_socket;
}
- /*
+ /*
* Step 2:
- * ... or S.state == TIMEWAIT,
+ * ... or S.state == TIMEWAIT,
* 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;
+ }
+
+ /*
+ * RFC 4340, sec. 9.2.1: Minimum Checksum Coverage
+ * o if MinCsCov = 0, only packets with CsCov = 0 are accepted
+ * o if MinCsCov > 0, also accept packets with CsCov >= MinCsCov
+ */
+ min_cov = dccp_sk(sk)->dccps_pcrlen;
+ if (dh->dccph_cscov && (min_cov == 0 || dh->dccph_cscov < min_cov)) {
+ dccp_pr_debug("Packet CsCov %d does not satisfy MinCsCov %d\n",
+ dh->dccph_cscov, min_cov);
+ /* FIXME: "Such packets SHOULD be reported using Data Dropped
+ * options (Section 11.7) with Drop Code 0, Protocol
+ * Constraints." */
+ goto discard_and_relse;
}
if (!xfrm4_policy_check(sk, XFRM_POLICY_IN, skb))
goto discard_and_relse;
nf_reset(skb);
- return sk_receive_skb(sk, skb);
+ return sk_receive_skb(sk, skb, 1);
no_dccp_socket:
if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb))
goto discard_it;
/*
* Step 2:
+ * If no socket ...
* Generate Reset(No Connection) unless P.type == Reset
* Drop packet and return
*/
if (dh->dccph_type != DCCP_PKT_RESET) {
DCCP_SKB_CB(skb)->dccpd_reset_code =
DCCP_RESET_CODE_NO_CONNECTION;
- dccp_v4_ctl_send_reset(skb);
+ dccp_v4_ctl_send_reset(sk, skb);
}
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;
}
-struct inet_connection_sock_af_ops dccp_ipv4_af_ops = {
- .queue_xmit = ip_queue_xmit,
- .send_check = dccp_v4_send_check,
- .rebuild_header = inet_sk_rebuild_header,
- .conn_request = dccp_v4_conn_request,
- .syn_recv_sock = dccp_v4_request_recv_sock,
- .net_header_len = sizeof(struct iphdr),
- .setsockopt = ip_setsockopt,
- .getsockopt = ip_getsockopt,
- .addr2sockaddr = inet_csk_addr2sockaddr,
- .sockaddr_len = sizeof(struct sockaddr_in),
+static struct inet_connection_sock_af_ops dccp_ipv4_af_ops = {
+ .queue_xmit = ip_queue_xmit,
+ .send_check = dccp_v4_send_check,
+ .rebuild_header = inet_sk_rebuild_header,
+ .conn_request = dccp_v4_conn_request,
+ .syn_recv_sock = dccp_v4_request_recv_sock,
+ .net_header_len = sizeof(struct iphdr),
+ .setsockopt = ip_setsockopt,
+ .getsockopt = ip_getsockopt,
+ .addr2sockaddr = inet_csk_addr2sockaddr,
+ .sockaddr_len = sizeof(struct sockaddr_in),
+#ifdef CONFIG_COMPAT
+ .compat_setsockopt = compat_ip_setsockopt,
+ .compat_getsockopt = compat_ip_getsockopt,
+#endif
};
-int dccp_v4_init_sock(struct sock *sk)
+static int dccp_v4_init_sock(struct sock *sk)
{
- struct dccp_sock *dp = dccp_sk(sk);
- struct inet_connection_sock *icsk = inet_csk(sk);
- static int dccp_ctl_socket_init = 1;
-
- dccp_options_init(&dp->dccps_options);
- do_gettimeofday(&dp->dccps_epoch);
-
- if (dp->dccps_options.dccpo_send_ack_vector) {
- dp->dccps_hc_rx_ackvec = dccp_ackvec_alloc(DCCP_MAX_ACKVEC_LEN,
- GFP_KERNEL);
- if (dp->dccps_hc_rx_ackvec == NULL)
- return -ENOMEM;
- }
-
- /*
- * FIXME: We're hardcoding the CCID, and doing this at this point makes
- * the listening (master) sock get CCID control blocks, which is not
- * necessary, but for now, to not mess with the test userspace apps,
- * lets leave it here, later the real solution is to do this in a
- * setsockopt(CCIDs-I-want/accept). -acme
- */
- if (likely(!dccp_ctl_socket_init)) {
- dp->dccps_hc_rx_ccid = ccid_init(dp->dccps_options.dccpo_rx_ccid,
- sk);
- dp->dccps_hc_tx_ccid = ccid_init(dp->dccps_options.dccpo_tx_ccid,
- sk);
- if (dp->dccps_hc_rx_ccid == NULL ||
- dp->dccps_hc_tx_ccid == NULL) {
- ccid_exit(dp->dccps_hc_rx_ccid, sk);
- ccid_exit(dp->dccps_hc_tx_ccid, sk);
- if (dp->dccps_options.dccpo_send_ack_vector) {
- dccp_ackvec_free(dp->dccps_hc_rx_ackvec);
- dp->dccps_hc_rx_ackvec = NULL;
- }
- dp->dccps_hc_rx_ccid = dp->dccps_hc_tx_ccid = NULL;
- return -ENOMEM;
- }
- } else
- dccp_ctl_socket_init = 0;
-
- dccp_init_xmit_timers(sk);
- icsk->icsk_rto = DCCP_TIMEOUT_INIT;
- sk->sk_state = DCCP_CLOSED;
- sk->sk_write_space = dccp_write_space;
- icsk->icsk_af_ops = &dccp_ipv4_af_ops;
- icsk->icsk_sync_mss = dccp_sync_mss;
- dp->dccps_mss_cache = 536;
- dp->dccps_role = DCCP_ROLE_UNDEFINED;
- dp->dccps_service = DCCP_SERVICE_INVALID_VALUE;
-
- return 0;
-}
-
-EXPORT_SYMBOL_GPL(dccp_v4_init_sock);
-
-int dccp_v4_destroy_sock(struct sock *sk)
-{
- struct dccp_sock *dp = dccp_sk(sk);
+ static __u8 dccp_v4_ctl_sock_initialized;
+ int err = dccp_init_sock(sk, dccp_v4_ctl_sock_initialized);
- /*
- * DCCP doesn't use sk_write_queue, just sk_send_head
- * for retransmissions
- */
- if (sk->sk_send_head != NULL) {
- kfree_skb(sk->sk_send_head);
- sk->sk_send_head = NULL;
- }
-
- /* Clean up a referenced DCCP bind bucket. */
- if (inet_csk(sk)->icsk_bind_hash != NULL)
- inet_put_port(&dccp_hashinfo, sk);
-
- kfree(dp->dccps_service_list);
- dp->dccps_service_list = NULL;
-
- ccid_hc_rx_exit(dp->dccps_hc_rx_ccid, sk);
- ccid_hc_tx_exit(dp->dccps_hc_tx_ccid, sk);
- if (dp->dccps_options.dccpo_send_ack_vector) {
- dccp_ackvec_free(dp->dccps_hc_rx_ackvec);
- dp->dccps_hc_rx_ackvec = NULL;
+ if (err == 0) {
+ if (unlikely(!dccp_v4_ctl_sock_initialized))
+ dccp_v4_ctl_sock_initialized = 1;
+ inet_csk(sk)->icsk_af_ops = &dccp_ipv4_af_ops;
}
- ccid_exit(dp->dccps_hc_rx_ccid, sk);
- ccid_exit(dp->dccps_hc_tx_ccid, sk);
- dp->dccps_hc_rx_ccid = dp->dccps_hc_tx_ccid = NULL;
- return 0;
-}
-
-EXPORT_SYMBOL_GPL(dccp_v4_destroy_sock);
-
-static void dccp_v4_reqsk_destructor(struct request_sock *req)
-{
- kfree(inet_rsk(req)->opt);
+ return err;
}
-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),
};
-struct proto dccp_prot = {
+static struct proto dccp_v4_prot = {
.name = "DCCP",
.owner = THIS_MODULE,
.close = dccp_close,
.sendmsg = dccp_sendmsg,
.recvmsg = dccp_recvmsg,
.backlog_rcv = dccp_v4_do_rcv,
- .hash = dccp_v4_hash,
+ .hash = dccp_hash,
.unhash = dccp_unhash,
.accept = inet_csk_accept,
.get_port = dccp_v4_get_port,
.shutdown = dccp_shutdown,
- .destroy = dccp_v4_destroy_sock,
+ .destroy = dccp_destroy_sock,
.orphan_count = &dccp_orphan_count,
.max_header = MAX_DCCP_HEADER,
.obj_size = sizeof(struct dccp_sock),
.rsk_prot = &dccp_request_sock_ops,
.twsk_prot = &dccp_timewait_sock_ops,
+#ifdef CONFIG_COMPAT
+ .compat_setsockopt = compat_dccp_setsockopt,
+ .compat_getsockopt = compat_dccp_getsockopt,
+#endif
+};
+
+static struct net_protocol dccp_v4_protocol = {
+ .handler = dccp_v4_rcv,
+ .err_handler = dccp_v4_err,
+ .no_policy = 1,
};
-EXPORT_SYMBOL_GPL(dccp_prot);
+static const struct proto_ops inet_dccp_ops = {
+ .family = PF_INET,
+ .owner = THIS_MODULE,
+ .release = inet_release,
+ .bind = inet_bind,
+ .connect = inet_stream_connect,
+ .socketpair = sock_no_socketpair,
+ .accept = inet_accept,
+ .getname = inet_getname,
+ /* FIXME: work on tcp_poll to rename it to inet_csk_poll */
+ .poll = dccp_poll,
+ .ioctl = inet_ioctl,
+ /* FIXME: work on inet_listen to rename it to sock_common_listen */
+ .listen = inet_dccp_listen,
+ .shutdown = inet_shutdown,
+ .setsockopt = sock_common_setsockopt,
+ .getsockopt = sock_common_getsockopt,
+ .sendmsg = inet_sendmsg,
+ .recvmsg = sock_common_recvmsg,
+ .mmap = sock_no_mmap,
+ .sendpage = sock_no_sendpage,
+#ifdef CONFIG_COMPAT
+ .compat_setsockopt = compat_sock_common_setsockopt,
+ .compat_getsockopt = compat_sock_common_getsockopt,
+#endif
+};
+
+static struct inet_protosw dccp_v4_protosw = {
+ .type = SOCK_DCCP,
+ .protocol = IPPROTO_DCCP,
+ .prot = &dccp_v4_prot,
+ .ops = &inet_dccp_ops,
+ .capability = -1,
+ .no_check = 0,
+ .flags = INET_PROTOSW_ICSK,
+};
+
+static int __init dccp_v4_init(void)
+{
+ int err = proto_register(&dccp_v4_prot, 1);
+
+ if (err != 0)
+ goto out;
+
+ err = inet_add_protocol(&dccp_v4_protocol, IPPROTO_DCCP);
+ if (err != 0)
+ goto out_proto_unregister;
+
+ inet_register_protosw(&dccp_v4_protosw);
+
+ err = inet_csk_ctl_sock_create(&dccp_v4_ctl_socket, PF_INET,
+ SOCK_DCCP, IPPROTO_DCCP);
+ if (err)
+ goto out_unregister_protosw;
+out:
+ return err;
+out_unregister_protosw:
+ inet_unregister_protosw(&dccp_v4_protosw);
+ inet_del_protocol(&dccp_v4_protocol, IPPROTO_DCCP);
+out_proto_unregister:
+ proto_unregister(&dccp_v4_prot);
+ goto out;
+}
+
+static void __exit dccp_v4_exit(void)
+{
+ inet_unregister_protosw(&dccp_v4_protosw);
+ inet_del_protocol(&dccp_v4_protocol, IPPROTO_DCCP);
+ proto_unregister(&dccp_v4_prot);
+}
+
+module_init(dccp_v4_init);
+module_exit(dccp_v4_exit);
+
+/*
+ * __stringify doesn't likes enums, so use SOCK_DCCP (6) and IPPROTO_DCCP (33)
+ * values directly, Also cover the case where the protocol is not specified,
+ * i.e. net-pf-PF_INET-proto-0-type-SOCK_DCCP
+ */
+MODULE_ALIAS("net-pf-" __stringify(PF_INET) "-proto-33-type-6");
+MODULE_ALIAS("net-pf-" __stringify(PF_INET) "-proto-0-type-6");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Arnaldo Carvalho de Melo <acme@mandriva.com>");
+MODULE_DESCRIPTION("DCCP - Datagram Congestion Controlled Protocol");