[DCCP]: Initial implementation
Development to this point was done on a subversion repository at:
http://oops.ghostprotocols.net:81/cgi-bin/viewcvs.cgi/dccp-2.6/
This repository will be kept at this site for the foreseable future,
so that interested parties can see the history of this code,
attributions, etc.
If I ever decide to take this offline I'll provide the full history at
some other suitable place.
Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/dccp/proto.c b/net/dccp/proto.c
new file mode 100644
index 0000000..70284e6
--- /dev/null
+++ b/net/dccp/proto.c
@@ -0,0 +1,818 @@
+/*
+ * net/dccp/proto.c
+ *
+ * An implementation of the DCCP protocol
+ * Arnaldo Carvalho de Melo <acme@conectiva.com.br>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/config.h>
+#include <linux/dccp.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/skbuff.h>
+#include <linux/netdevice.h>
+#include <linux/in.h>
+#include <linux/if_arp.h>
+#include <linux/init.h>
+#include <linux/random.h>
+#include <net/checksum.h>
+
+#include <net/inet_common.h>
+#include <net/ip.h>
+#include <net/protocol.h>
+#include <net/sock.h>
+#include <net/xfrm.h>
+
+#include <asm/semaphore.h>
+#include <linux/spinlock.h>
+#include <linux/timer.h>
+#include <linux/delay.h>
+#include <linux/poll.h>
+#include <linux/dccp.h>
+
+#include "ccid.h"
+#include "dccp.h"
+
+DEFINE_SNMP_STAT(struct dccp_mib, dccp_statistics);
+
+atomic_t dccp_orphan_count = ATOMIC_INIT(0);
+
+static struct net_protocol dccp_protocol = {
+ .handler = dccp_v4_rcv,
+ .err_handler = dccp_v4_err,
+};
+
+const char *dccp_packet_name(const int type)
+{
+ static const char *dccp_packet_names[] = {
+ [DCCP_PKT_REQUEST] = "REQUEST",
+ [DCCP_PKT_RESPONSE] = "RESPONSE",
+ [DCCP_PKT_DATA] = "DATA",
+ [DCCP_PKT_ACK] = "ACK",
+ [DCCP_PKT_DATAACK] = "DATAACK",
+ [DCCP_PKT_CLOSEREQ] = "CLOSEREQ",
+ [DCCP_PKT_CLOSE] = "CLOSE",
+ [DCCP_PKT_RESET] = "RESET",
+ [DCCP_PKT_SYNC] = "SYNC",
+ [DCCP_PKT_SYNCACK] = "SYNCACK",
+ };
+
+ if (type >= DCCP_NR_PKT_TYPES)
+ return "INVALID";
+ else
+ return dccp_packet_names[type];
+}
+
+EXPORT_SYMBOL_GPL(dccp_packet_name);
+
+const char *dccp_state_name(const int state)
+{
+ static char *dccp_state_names[] = {
+ [DCCP_OPEN] = "OPEN",
+ [DCCP_REQUESTING] = "REQUESTING",
+ [DCCP_PARTOPEN] = "PARTOPEN",
+ [DCCP_LISTEN] = "LISTEN",
+ [DCCP_RESPOND] = "RESPOND",
+ [DCCP_CLOSING] = "CLOSING",
+ [DCCP_TIME_WAIT] = "TIME_WAIT",
+ [DCCP_CLOSED] = "CLOSED",
+ };
+
+ if (state >= DCCP_MAX_STATES)
+ return "INVALID STATE!";
+ else
+ return dccp_state_names[state];
+}
+
+EXPORT_SYMBOL_GPL(dccp_state_name);
+
+static inline int dccp_listen_start(struct sock *sk)
+{
+ dccp_sk(sk)->dccps_role = DCCP_ROLE_LISTEN;
+ return inet_csk_listen_start(sk, TCP_SYNQ_HSIZE);
+}
+
+int dccp_disconnect(struct sock *sk, int flags)
+{
+ struct inet_connection_sock *icsk = inet_csk(sk);
+ struct inet_sock *inet = inet_sk(sk);
+ int err = 0;
+ const int old_state = sk->sk_state;
+
+ if (old_state != DCCP_CLOSED)
+ dccp_set_state(sk, DCCP_CLOSED);
+
+ /* ABORT function of RFC793 */
+ if (old_state == DCCP_LISTEN) {
+ inet_csk_listen_stop(sk);
+ /* FIXME: do the active reset thing */
+ } else if (old_state == DCCP_REQUESTING)
+ sk->sk_err = ECONNRESET;
+
+ dccp_clear_xmit_timers(sk);
+ __skb_queue_purge(&sk->sk_receive_queue);
+ if (sk->sk_send_head != NULL) {
+ __kfree_skb(sk->sk_send_head);
+ sk->sk_send_head = NULL;
+ }
+
+ inet->dport = 0;
+
+ if (!(sk->sk_userlocks & SOCK_BINDADDR_LOCK))
+ inet_reset_saddr(sk);
+
+ sk->sk_shutdown = 0;
+ sock_reset_flag(sk, SOCK_DONE);
+
+ icsk->icsk_backoff = 0;
+ inet_csk_delack_init(sk);
+ __sk_dst_reset(sk);
+
+ BUG_TRAP(!inet->num || icsk->icsk_bind_hash);
+
+ sk->sk_error_report(sk);
+ return err;
+}
+
+int dccp_ioctl(struct sock *sk, int cmd, unsigned long arg)
+{
+ dccp_pr_debug("entry\n");
+ return -ENOIOCTLCMD;
+}
+
+int dccp_setsockopt(struct sock *sk, int level, int optname,
+ char *optval, int optlen)
+{
+ dccp_pr_debug("entry\n");
+
+ if (level != SOL_DCCP)
+ return ip_setsockopt(sk, level, optname, optval, optlen);
+
+ return -EOPNOTSUPP;
+}
+
+int dccp_getsockopt(struct sock *sk, int level, int optname,
+ char *optval, int *optlen)
+{
+ dccp_pr_debug("entry\n");
+
+ if (level != SOL_DCCP)
+ return ip_getsockopt(sk, level, optname, optval, optlen);
+
+ return -EOPNOTSUPP;
+}
+
+int dccp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
+ size_t len)
+{
+ const struct dccp_sock *dp = dccp_sk(sk);
+ const int flags = msg->msg_flags;
+ const int noblock = flags & MSG_DONTWAIT;
+ struct sk_buff *skb;
+ int rc, size;
+ long timeo;
+
+ if (len > dp->dccps_mss_cache)
+ return -EMSGSIZE;
+
+ lock_sock(sk);
+
+ timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT);
+
+ /*
+ * We have to use sk_stream_wait_connect here to set sk_write_pending,
+ * so that the trick in dccp_rcv_request_sent_state_process.
+ */
+ /* Wait for a connection to finish. */
+ if ((1 << sk->sk_state) & ~(DCCPF_OPEN | DCCPF_PARTOPEN | DCCPF_CLOSING))
+ if ((rc = sk_stream_wait_connect(sk, &timeo)) != 0)
+ goto out_err;
+
+ size = sk->sk_prot->max_header + len;
+ release_sock(sk);
+ skb = sock_alloc_send_skb(sk, size, noblock, &rc);
+ lock_sock(sk);
+
+ if (skb == NULL)
+ goto out_release;
+
+ skb_reserve(skb, sk->sk_prot->max_header);
+ rc = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len);
+ if (rc == 0) {
+ struct dccp_skb_cb *dcb = DCCP_SKB_CB(skb);
+ const struct dccp_ackpkts *ap = dp->dccps_hc_rx_ackpkts;
+ long delay;
+
+ /*
+ * XXX: This is just to match the Waikato tree CA interaction
+ * points, after the CCID3 code is stable and I have a better
+ * understanding of behaviour I'll change this to look more like
+ * TCP.
+ */
+ while (1) {
+ rc = ccid_hc_tx_send_packet(dp->dccps_hc_tx_ccid, sk,
+ skb, len, &delay);
+ if (rc == 0)
+ break;
+ if (rc != -EAGAIN)
+ goto out_discard;
+ if (delay > timeo)
+ goto out_discard;
+ release_sock(sk);
+ delay = schedule_timeout(delay);
+ lock_sock(sk);
+ timeo -= delay;
+ if (signal_pending(current))
+ goto out_interrupted;
+ rc = -EPIPE;
+ if (!(sk->sk_state == DCCP_PARTOPEN || sk->sk_state == DCCP_OPEN))
+ goto out_discard;
+ }
+
+ if (sk->sk_state == DCCP_PARTOPEN) {
+ /* See 8.1.5. Handshake Completion */
+ inet_csk_schedule_ack(sk);
+ inet_csk_reset_xmit_timer(sk, ICSK_TIME_DACK, inet_csk(sk)->icsk_rto, TCP_RTO_MAX);
+ dcb->dccpd_type = DCCP_PKT_DATAACK;
+ /* FIXME: we really should have a dccps_ack_pending or use icsk */
+ } else if (inet_csk_ack_scheduled(sk) ||
+ (dp->dccps_options.dccpo_send_ack_vector &&
+ ap->dccpap_buf_ackno != DCCP_MAX_SEQNO + 1 &&
+ ap->dccpap_ack_seqno == DCCP_MAX_SEQNO + 1))
+ dcb->dccpd_type = DCCP_PKT_DATAACK;
+ else
+ dcb->dccpd_type = DCCP_PKT_DATA;
+ dccp_transmit_skb(sk, skb);
+ ccid_hc_tx_packet_sent(dp->dccps_hc_tx_ccid, sk, 0, len);
+ } else {
+out_discard:
+ kfree_skb(skb);
+ }
+out_release:
+ release_sock(sk);
+ return rc ? : len;
+out_err:
+ rc = sk_stream_error(sk, flags, rc);
+ goto out_release;
+out_interrupted:
+ rc = sock_intr_errno(timeo);
+ goto out_discard;
+}
+
+EXPORT_SYMBOL(dccp_sendmsg);
+
+int dccp_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
+ size_t len, int nonblock, int flags, int *addr_len)
+{
+ const struct dccp_hdr *dh;
+ int copied = 0;
+ unsigned long used;
+ int err;
+ int target; /* Read at least this many bytes */
+ long timeo;
+
+ lock_sock(sk);
+
+ err = -ENOTCONN;
+ if (sk->sk_state == DCCP_LISTEN)
+ goto out;
+
+ timeo = sock_rcvtimeo(sk, nonblock);
+
+ /* Urgent data needs to be handled specially. */
+ if (flags & MSG_OOB)
+ goto recv_urg;
+
+ /* FIXME */
+#if 0
+ seq = &tp->copied_seq;
+ if (flags & MSG_PEEK) {
+ peek_seq = tp->copied_seq;
+ seq = &peek_seq;
+ }
+#endif
+
+ target = sock_rcvlowat(sk, flags & MSG_WAITALL, len);
+
+ do {
+ struct sk_buff *skb;
+ u32 offset;
+
+ /* FIXME */
+#if 0
+ /* Are we at urgent data? Stop if we have read anything or have SIGURG pending. */
+ if (tp->urg_data && tp->urg_seq == *seq) {
+ if (copied)
+ break;
+ if (signal_pending(current)) {
+ copied = timeo ? sock_intr_errno(timeo) : -EAGAIN;
+ break;
+ }
+ }
+#endif
+
+ /* Next get a buffer. */
+
+ skb = skb_peek(&sk->sk_receive_queue);
+ do {
+ if (!skb)
+ break;
+
+ offset = 0;
+ dh = dccp_hdr(skb);
+
+ if (dh->dccph_type == DCCP_PKT_DATA ||
+ dh->dccph_type == DCCP_PKT_DATAACK)
+ goto found_ok_skb;
+
+ if (dh->dccph_type == DCCP_PKT_RESET ||
+ dh->dccph_type == DCCP_PKT_CLOSE) {
+ dccp_pr_debug("found fin ok!\n");
+ goto found_fin_ok;
+ }
+ dccp_pr_debug("packet_type=%s\n", dccp_packet_name(dh->dccph_type));
+ BUG_TRAP(flags & MSG_PEEK);
+ skb = skb->next;
+ } while (skb != (struct sk_buff *)&sk->sk_receive_queue);
+
+ /* Well, if we have backlog, try to process it now yet. */
+ if (copied >= target && !sk->sk_backlog.tail)
+ break;
+
+ if (copied) {
+ if (sk->sk_err ||
+ sk->sk_state == DCCP_CLOSED ||
+ (sk->sk_shutdown & RCV_SHUTDOWN) ||
+ !timeo ||
+ signal_pending(current) ||
+ (flags & MSG_PEEK))
+ break;
+ } else {
+ if (sock_flag(sk, SOCK_DONE))
+ break;
+
+ if (sk->sk_err) {
+ copied = sock_error(sk);
+ break;
+ }
+
+ if (sk->sk_shutdown & RCV_SHUTDOWN)
+ break;
+
+ if (sk->sk_state == DCCP_CLOSED) {
+ if (!sock_flag(sk, SOCK_DONE)) {
+ /* This occurs when user tries to read
+ * from never connected socket.
+ */
+ copied = -ENOTCONN;
+ break;
+ }
+ break;
+ }
+
+ if (!timeo) {
+ copied = -EAGAIN;
+ break;
+ }
+
+ if (signal_pending(current)) {
+ copied = sock_intr_errno(timeo);
+ break;
+ }
+ }
+
+ /* FIXME: cleanup_rbuf(sk, copied); */
+
+ if (copied >= target) {
+ /* Do not sleep, just process backlog. */
+ release_sock(sk);
+ lock_sock(sk);
+ } else
+ sk_wait_data(sk, &timeo);
+
+ continue;
+
+ found_ok_skb:
+ /* Ok so how much can we use? */
+ used = skb->len - offset;
+ if (len < used)
+ used = len;
+
+ if (!(flags & MSG_TRUNC)) {
+ err = skb_copy_datagram_iovec(skb, offset,
+ msg->msg_iov, used);
+ if (err) {
+ /* Exception. Bailout! */
+ if (!copied)
+ copied = -EFAULT;
+ break;
+ }
+ }
+
+ copied += used;
+ len -= used;
+
+ /* FIXME: tcp_rcv_space_adjust(sk); */
+
+//skip_copy:
+ if (used + offset < skb->len)
+ continue;
+
+ if (!(flags & MSG_PEEK))
+ sk_eat_skb(sk, skb);
+ continue;
+ found_fin_ok:
+ if (!(flags & MSG_PEEK))
+ sk_eat_skb(sk, skb);
+ break;
+
+ } while (len > 0);
+
+ /* According to UNIX98, msg_name/msg_namelen are ignored
+ * on connected socket. I was just happy when found this 8) --ANK
+ */
+
+ /* Clean up data we have read: This will do ACK frames. */
+ /* FIXME: cleanup_rbuf(sk, copied); */
+
+ release_sock(sk);
+ return copied;
+
+out:
+ release_sock(sk);
+ return err;
+
+recv_urg:
+ /* FIXME: err = tcp_recv_urg(sk, timeo, msg, len, flags, addr_len); */
+ goto out;
+}
+
+static int inet_dccp_listen(struct socket *sock, int backlog)
+{
+ struct sock *sk = sock->sk;
+ unsigned char old_state;
+ int err;
+
+ lock_sock(sk);
+
+ err = -EINVAL;
+ if (sock->state != SS_UNCONNECTED || sock->type != SOCK_DCCP)
+ goto out;
+
+ old_state = sk->sk_state;
+ if (!((1 << old_state) & (DCCPF_CLOSED | DCCPF_LISTEN)))
+ goto out;
+
+ /* Really, if the socket is already in listen state
+ * we can only allow the backlog to be adjusted.
+ */
+ if (old_state != DCCP_LISTEN) {
+ /*
+ * FIXME: here it probably should be sk->sk_prot->listen_start
+ * see tcp_listen_start
+ */
+ err = dccp_listen_start(sk);
+ if (err)
+ goto out;
+ }
+ sk->sk_max_ack_backlog = backlog;
+ err = 0;
+
+out:
+ release_sock(sk);
+ return err;
+}
+
+static const unsigned char dccp_new_state[] = {
+ /* current state: new state: action: */
+ [0] = DCCP_CLOSED,
+ [DCCP_OPEN] = DCCP_CLOSING | DCCP_ACTION_FIN,
+ [DCCP_REQUESTING] = DCCP_CLOSED,
+ [DCCP_PARTOPEN] = DCCP_CLOSING | DCCP_ACTION_FIN,
+ [DCCP_LISTEN] = DCCP_CLOSED,
+ [DCCP_RESPOND] = DCCP_CLOSED,
+ [DCCP_CLOSING] = DCCP_CLOSED,
+ [DCCP_TIME_WAIT] = DCCP_CLOSED,
+ [DCCP_CLOSED] = DCCP_CLOSED,
+};
+
+static int dccp_close_state(struct sock *sk)
+{
+ const int next = dccp_new_state[sk->sk_state];
+ const int ns = next & DCCP_STATE_MASK;
+
+ if (ns != sk->sk_state)
+ dccp_set_state(sk, ns);
+
+ return next & DCCP_ACTION_FIN;
+}
+
+void dccp_close(struct sock *sk, long timeout)
+{
+ struct sk_buff *skb;
+
+ lock_sock(sk);
+
+ sk->sk_shutdown = SHUTDOWN_MASK;
+
+ if (sk->sk_state == DCCP_LISTEN) {
+ dccp_set_state(sk, DCCP_CLOSED);
+
+ /* Special case. */
+ inet_csk_listen_stop(sk);
+
+ goto adjudge_to_death;
+ }
+
+ /*
+ * We need to flush the recv. buffs. We do this only on the
+ * descriptor close, not protocol-sourced closes, because the
+ *reader process may not have drained the data yet!
+ */
+ /* FIXME: check for unread data */
+ while ((skb = __skb_dequeue(&sk->sk_receive_queue)) != NULL) {
+ __kfree_skb(skb);
+ }
+
+ if (sock_flag(sk, SOCK_LINGER) && !sk->sk_lingertime) {
+ /* Check zero linger _after_ checking for unread data. */
+ sk->sk_prot->disconnect(sk, 0);
+ } else if (dccp_close_state(sk)) {
+ dccp_send_close(sk);
+ }
+
+ sk_stream_wait_close(sk, timeout);
+
+adjudge_to_death:
+ release_sock(sk);
+ /*
+ * Now socket is owned by kernel and we acquire BH lock
+ * to finish close. No need to check for user refs.
+ */
+ local_bh_disable();
+ bh_lock_sock(sk);
+ BUG_TRAP(!sock_owned_by_user(sk));
+
+ sock_hold(sk);
+ sock_orphan(sk);
+
+ if (sk->sk_state != DCCP_CLOSED)
+ dccp_set_state(sk, DCCP_CLOSED);
+
+ atomic_inc(&dccp_orphan_count);
+ if (sk->sk_state == DCCP_CLOSED)
+ inet_csk_destroy_sock(sk);
+
+ /* Otherwise, socket is reprieved until protocol close. */
+
+ bh_unlock_sock(sk);
+ local_bh_enable();
+ sock_put(sk);
+}
+
+void dccp_shutdown(struct sock *sk, int how)
+{
+ dccp_pr_debug("entry\n");
+}
+
+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,
+ .poll = sock_no_poll,
+ .ioctl = inet_ioctl,
+ .listen = inet_dccp_listen, /* FIXME: work on inet_listen to rename it to sock_common_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,
+};
+
+extern struct net_proto_family inet_family_ops;
+
+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 = 0,
+};
+
+/*
+ * 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.
+ */
+struct socket *dccp_ctl_socket;
+
+static char dccp_ctl_socket_err_msg[] __initdata =
+ KERN_ERR "DCCP: Failed to create the control socket.\n";
+
+static int __init dccp_ctl_sock_init(void)
+{
+ int rc = sock_create_kern(PF_INET, SOCK_DCCP, IPPROTO_DCCP,
+ &dccp_ctl_socket);
+ if (rc < 0)
+ printk(dccp_ctl_socket_err_msg);
+ else {
+ dccp_ctl_socket->sk->sk_allocation = GFP_ATOMIC;
+ inet_sk(dccp_ctl_socket->sk)->uc_ttl = -1;
+
+ /* Unhash it so that IP input processing does not even
+ * see it, we do not wish this socket to see incoming
+ * packets.
+ */
+ dccp_ctl_socket->sk->sk_prot->unhash(dccp_ctl_socket->sk);
+ }
+
+ return rc;
+}
+
+static void __exit dccp_ctl_sock_exit(void)
+{
+ if (dccp_ctl_socket != NULL)
+ sock_release(dccp_ctl_socket);
+}
+
+static int __init init_dccp_v4_mibs(void)
+{
+ int rc = -ENOMEM;
+
+ dccp_statistics[0] = alloc_percpu(struct dccp_mib);
+ if (dccp_statistics[0] == NULL)
+ goto out;
+
+ dccp_statistics[1] = alloc_percpu(struct dccp_mib);
+ if (dccp_statistics[1] == NULL)
+ goto out_free_one;
+
+ rc = 0;
+out:
+ return rc;
+out_free_one:
+ free_percpu(dccp_statistics[0]);
+ dccp_statistics[0] = NULL;
+ goto out;
+
+}
+
+static int thash_entries;
+module_param(thash_entries, int, 0444);
+MODULE_PARM_DESC(thash_entries, "Number of ehash buckets");
+
+int dccp_debug;
+module_param(dccp_debug, int, 0444);
+MODULE_PARM_DESC(dccp_debug, "Enable debug messages");
+
+static int __init dccp_init(void)
+{
+ unsigned long goal;
+ int ehash_order, bhash_order, i;
+ int rc = proto_register(&dccp_v4_prot, 1);
+
+ if (rc)
+ goto out;
+
+ dccp_hashinfo.bind_bucket_cachep = kmem_cache_create("dccp_bind_bucket",
+ sizeof(struct inet_bind_bucket),
+ 0, SLAB_HWCACHE_ALIGN,
+ NULL, NULL);
+ if (!dccp_hashinfo.bind_bucket_cachep)
+ goto out_proto_unregister;
+
+ /*
+ * Size and allocate the main established and bind bucket
+ * hash tables.
+ *
+ * The methodology is similar to that of the buffer cache.
+ */
+ if (num_physpages >= (128 * 1024))
+ goal = num_physpages >> (21 - PAGE_SHIFT);
+ else
+ goal = num_physpages >> (23 - PAGE_SHIFT);
+
+ if (thash_entries)
+ goal = (thash_entries * sizeof(struct inet_ehash_bucket)) >> PAGE_SHIFT;
+ for (ehash_order = 0; (1UL << ehash_order) < goal; ehash_order++)
+ ;
+ do {
+ dccp_hashinfo.ehash_size = (1UL << ehash_order) * PAGE_SIZE /
+ sizeof(struct inet_ehash_bucket);
+ dccp_hashinfo.ehash_size >>= 1;
+ while (dccp_hashinfo.ehash_size & (dccp_hashinfo.ehash_size - 1))
+ dccp_hashinfo.ehash_size--;
+ dccp_hashinfo.ehash = (struct inet_ehash_bucket *)
+ __get_free_pages(GFP_ATOMIC, ehash_order);
+ } while (!dccp_hashinfo.ehash && --ehash_order > 0);
+
+ if (!dccp_hashinfo.ehash) {
+ printk(KERN_CRIT "Failed to allocate DCCP "
+ "established hash table\n");
+ goto out_free_bind_bucket_cachep;
+ }
+
+ for (i = 0; i < (dccp_hashinfo.ehash_size << 1); i++) {
+ rwlock_init(&dccp_hashinfo.ehash[i].lock);
+ INIT_HLIST_HEAD(&dccp_hashinfo.ehash[i].chain);
+ }
+
+ bhash_order = ehash_order;
+
+ do {
+ dccp_hashinfo.bhash_size = (1UL << bhash_order) * PAGE_SIZE /
+ sizeof(struct inet_bind_hashbucket);
+ if ((dccp_hashinfo.bhash_size > (64 * 1024)) && bhash_order > 0)
+ continue;
+ dccp_hashinfo.bhash = (struct inet_bind_hashbucket *)
+ __get_free_pages(GFP_ATOMIC, bhash_order);
+ } while (!dccp_hashinfo.bhash && --bhash_order >= 0);
+
+ if (!dccp_hashinfo.bhash) {
+ printk(KERN_CRIT "Failed to allocate DCCP bind hash table\n");
+ goto out_free_dccp_ehash;
+ }
+
+ for (i = 0; i < dccp_hashinfo.bhash_size; i++) {
+ spin_lock_init(&dccp_hashinfo.bhash[i].lock);
+ INIT_HLIST_HEAD(&dccp_hashinfo.bhash[i].chain);
+ }
+
+ if (init_dccp_v4_mibs())
+ goto out_free_dccp_bhash;
+
+ rc = -EAGAIN;
+ if (inet_add_protocol(&dccp_protocol, IPPROTO_DCCP))
+ goto out_free_dccp_v4_mibs;
+
+ inet_register_protosw(&dccp_v4_protosw);
+
+ rc = dccp_ctl_sock_init();
+ if (rc)
+ goto out_unregister_protosw;
+out:
+ return rc;
+out_unregister_protosw:
+ inet_unregister_protosw(&dccp_v4_protosw);
+ inet_del_protocol(&dccp_protocol, IPPROTO_DCCP);
+out_free_dccp_v4_mibs:
+ free_percpu(dccp_statistics[0]);
+ free_percpu(dccp_statistics[1]);
+ dccp_statistics[0] = dccp_statistics[1] = NULL;
+out_free_dccp_bhash:
+ free_pages((unsigned long)dccp_hashinfo.bhash, bhash_order);
+ dccp_hashinfo.bhash = NULL;
+out_free_dccp_ehash:
+ free_pages((unsigned long)dccp_hashinfo.ehash, ehash_order);
+ dccp_hashinfo.ehash = NULL;
+out_free_bind_bucket_cachep:
+ kmem_cache_destroy(dccp_hashinfo.bind_bucket_cachep);
+ dccp_hashinfo.bind_bucket_cachep = NULL;
+out_proto_unregister:
+ proto_unregister(&dccp_v4_prot);
+ goto out;
+}
+
+static const char dccp_del_proto_err_msg[] __exitdata =
+ KERN_ERR "can't remove dccp net_protocol\n";
+
+static void __exit dccp_fini(void)
+{
+ dccp_ctl_sock_exit();
+
+ inet_unregister_protosw(&dccp_v4_protosw);
+
+ if (inet_del_protocol(&dccp_protocol, IPPROTO_DCCP) < 0)
+ printk(dccp_del_proto_err_msg);
+
+ /* Free the control endpoint. */
+ sock_release(dccp_ctl_socket);
+
+ proto_unregister(&dccp_v4_prot);
+
+ kmem_cache_destroy(dccp_hashinfo.bind_bucket_cachep);
+}
+
+module_init(dccp_init);
+module_exit(dccp_fini);
+
+/* __stringify doesn't likes enums, so use SOCK_DCCP (6) value directly */
+MODULE_ALIAS("net-pf-" __stringify(PF_INET) "-6");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Arnaldo Carvalho de Melo <acme@conectiva.com.br>");
+MODULE_DESCRIPTION("DCCP - Datagram Congestion Controlled Protocol");