--- /dev/null
+/*
+ * 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/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 <linux/slab.h>
+#include <net/checksum.h>
+
+#include <net/inet_sock.h>
+#include <net/sock.h>
+#include <net/xfrm.h>
+
+#include <asm/ioctls.h>
+#include <linux/spinlock.h>
+#include <linux/timer.h>
+#include <linux/delay.h>
+#include <linux/poll.h>
+
+#include "ccid.h"
+#include "dccp.h"
+#include "feat.h"
+
+DEFINE_SNMP_STAT(struct dccp_mib, dccp_statistics) __read_mostly;
+
+EXPORT_SYMBOL_GPL(dccp_statistics);
+
+struct percpu_counter dccp_orphan_count;
+EXPORT_SYMBOL_GPL(dccp_orphan_count);
+
+struct inet_hashinfo dccp_hashinfo;
+EXPORT_SYMBOL_GPL(dccp_hashinfo);
+
+/* the maximum queue length for tx in packets. 0 is no limit */
+int sysctl_dccp_tx_qlen __read_mostly = 5;
+
+#ifdef CONFIG_IP_DCCP_DEBUG
+static const char *dccp_state_name(const int state)
+{
+ static const char *const dccp_state_names[] = {
+ [DCCP_OPEN] = "OPEN",
+ [DCCP_REQUESTING] = "REQUESTING",
+ [DCCP_PARTOPEN] = "PARTOPEN",
+ [DCCP_LISTEN] = "LISTEN",
+ [DCCP_RESPOND] = "RESPOND",
+ [DCCP_CLOSING] = "CLOSING",
+ [DCCP_ACTIVE_CLOSEREQ] = "CLOSEREQ",
+ [DCCP_PASSIVE_CLOSE] = "PASSIVE_CLOSE",
+ [DCCP_PASSIVE_CLOSEREQ] = "PASSIVE_CLOSEREQ",
+ [DCCP_TIME_WAIT] = "TIME_WAIT",
+ [DCCP_CLOSED] = "CLOSED",
+ };
+
+ if (state >= DCCP_MAX_STATES)
+ return "INVALID STATE!";
+ else
+ return dccp_state_names[state];
+}
+#endif
+
+void dccp_set_state(struct sock *sk, const int state)
+{
+ const int oldstate = sk->sk_state;
+
+ dccp_pr_debug("%s(%p) %s --> %s\n", dccp_role(sk), sk,
+ dccp_state_name(oldstate), dccp_state_name(state));
+ WARN_ON(state == oldstate);
+
+ switch (state) {
+ case DCCP_OPEN:
+ if (oldstate != DCCP_OPEN)
+ DCCP_INC_STATS(DCCP_MIB_CURRESTAB);
+ /* Client retransmits all Confirm options until entering OPEN */
+ if (oldstate == DCCP_PARTOPEN)
+ dccp_feat_list_purge(&dccp_sk(sk)->dccps_featneg);
+ break;
+
+ case DCCP_CLOSED:
+ if (oldstate == DCCP_OPEN || oldstate == DCCP_ACTIVE_CLOSEREQ ||
+ oldstate == DCCP_CLOSING)
+ DCCP_INC_STATS(DCCP_MIB_ESTABRESETS);
+
+ sk->sk_prot->unhash(sk);
+ if (inet_csk(sk)->icsk_bind_hash != NULL &&
+ !(sk->sk_userlocks & SOCK_BINDPORT_LOCK))
+ inet_put_port(sk);
+ /* fall through */
+ default:
+ if (oldstate == DCCP_OPEN)
+ DCCP_DEC_STATS(DCCP_MIB_CURRESTAB);
+ }
+
+ /* Change state AFTER socket is unhashed to avoid closed
+ * socket sitting in hash tables.
+ */
+ sk->sk_state = state;
+}
+
+EXPORT_SYMBOL_GPL(dccp_set_state);
+
+static void dccp_finish_passive_close(struct sock *sk)
+{
+ switch (sk->sk_state) {
+ case DCCP_PASSIVE_CLOSE:
+ /* Node (client or server) has received Close packet. */
+ dccp_send_reset(sk, DCCP_RESET_CODE_CLOSED);
+ dccp_set_state(sk, DCCP_CLOSED);
+ break;
+ case DCCP_PASSIVE_CLOSEREQ:
+ /*
+ * Client received CloseReq. We set the `active' flag so that
+ * dccp_send_close() retransmits the Close as per RFC 4340, 8.3.
+ */
+ dccp_send_close(sk, 1);
+ dccp_set_state(sk, DCCP_CLOSING);
+ }
+}
+
+void dccp_done(struct sock *sk)
+{
+ dccp_set_state(sk, DCCP_CLOSED);
+ dccp_clear_xmit_timers(sk);
+
+ sk->sk_shutdown = SHUTDOWN_MASK;
+
+ if (!sock_flag(sk, SOCK_DEAD))
+ sk->sk_state_change(sk);
+ else
+ inet_csk_destroy_sock(sk);
+}
+
+EXPORT_SYMBOL_GPL(dccp_done);
+
+const char *dccp_packet_name(const int type)
+{
+ static const char *const 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);
+
+int dccp_init_sock(struct sock *sk, const __u8 ctl_sock_initialized)
+{
+ struct dccp_sock *dp = dccp_sk(sk);
+ struct inet_connection_sock *icsk = inet_csk(sk);
+
+ icsk->icsk_rto = DCCP_TIMEOUT_INIT;
+ icsk->icsk_syn_retries = sysctl_dccp_request_retries;
+ sk->sk_state = DCCP_CLOSED;
+ sk->sk_write_space = dccp_write_space;
+ icsk->icsk_sync_mss = dccp_sync_mss;
+ dp->dccps_mss_cache = 536;
+ dp->dccps_rate_last = jiffies;
+ dp->dccps_role = DCCP_ROLE_UNDEFINED;
+ dp->dccps_service = DCCP_SERVICE_CODE_IS_ABSENT;
+ dp->dccps_tx_qlen = sysctl_dccp_tx_qlen;
+
+ dccp_init_xmit_timers(sk);
+
+ INIT_LIST_HEAD(&dp->dccps_featneg);
+ /* control socket doesn't need feat nego */
+ if (likely(ctl_sock_initialized))
+ return dccp_feat_init(sk);
+ return 0;
+}
+
+EXPORT_SYMBOL_GPL(dccp_init_sock);
+
+void dccp_destroy_sock(struct sock *sk)
+{
+ struct dccp_sock *dp = dccp_sk(sk);
+
+ /*
+ * 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(sk);
+
+ kfree(dp->dccps_service_list);
+ dp->dccps_service_list = NULL;
+
+ if (dp->dccps_hc_rx_ackvec != NULL) {
+ dccp_ackvec_free(dp->dccps_hc_rx_ackvec);
+ dp->dccps_hc_rx_ackvec = NULL;
+ }
+ ccid_hc_rx_delete(dp->dccps_hc_rx_ccid, sk);
+ ccid_hc_tx_delete(dp->dccps_hc_tx_ccid, sk);
+ dp->dccps_hc_rx_ccid = dp->dccps_hc_tx_ccid = NULL;
+
+ /* clean up feature negotiation state */
+ dccp_feat_list_purge(&dp->dccps_featneg);
+}
+
+EXPORT_SYMBOL_GPL(dccp_destroy_sock);
+
+static inline int dccp_listen_start(struct sock *sk, int backlog)
+{
+ struct dccp_sock *dp = dccp_sk(sk);
+
+ dp->dccps_role = DCCP_ROLE_LISTEN;
+ /* do not start to listen if feature negotiation setup fails */
+ if (dccp_feat_finalise_settings(dp))
+ return -EPROTO;
+ return inet_csk_listen_start(sk, backlog);
+}
+
+static inline int dccp_need_reset(int state)
+{
+ return state != DCCP_CLOSED && state != DCCP_LISTEN &&
+ state != DCCP_REQUESTING;
+}
+
+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);
+
+ /*
+ * This corresponds to the ABORT function of RFC793, sec. 3.8
+ * TCP uses a RST segment, DCCP a Reset packet with Code 2, "Aborted".
+ */
+ if (old_state == DCCP_LISTEN) {
+ inet_csk_listen_stop(sk);
+ } else if (dccp_need_reset(old_state)) {
+ dccp_send_reset(sk, DCCP_RESET_CODE_ABORTED);
+ sk->sk_err = ECONNRESET;
+ } else if (old_state == DCCP_REQUESTING)
+ sk->sk_err = ECONNRESET;
+
+ dccp_clear_xmit_timers(sk);
+
+ __skb_queue_purge(&sk->sk_receive_queue);
+ __skb_queue_purge(&sk->sk_write_queue);
+ if (sk->sk_send_head != NULL) {
+ __kfree_skb(sk->sk_send_head);
+ sk->sk_send_head = NULL;
+ }
+
+ inet->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);
+
+ WARN_ON(inet->inet_num && !icsk->icsk_bind_hash);
+
+ sk->sk_error_report(sk);
+ return err;
+}
+
+EXPORT_SYMBOL_GPL(dccp_disconnect);
+
+/*
+ * Wait for a DCCP event.
+ *
+ * Note that we don't need to lock the socket, as the upper poll layers
+ * take care of normal races (between the test and the event) and we don't
+ * go look at any of the socket buffers directly.
+ */
+unsigned int dccp_poll(struct file *file, struct socket *sock,
+ poll_table *wait)
+{
+ unsigned int mask;
+ struct sock *sk = sock->sk;
+
+ sock_poll_wait(file, sk_sleep(sk), wait);
+ if (sk->sk_state == DCCP_LISTEN)
+ return inet_csk_listen_poll(sk);
+
+ /* Socket is not locked. We are protected from async events
+ by poll logic and correct handling of state changes
+ made by another threads is impossible in any case.
+ */
+
+ mask = 0;
+ if (sk->sk_err)
+ mask = POLLERR;
+
+ if (sk->sk_shutdown == SHUTDOWN_MASK || sk->sk_state == DCCP_CLOSED)
+ mask |= POLLHUP;
+ if (sk->sk_shutdown & RCV_SHUTDOWN)
+ mask |= POLLIN | POLLRDNORM | POLLRDHUP;
+
+ /* Connected? */
+ if ((1 << sk->sk_state) & ~(DCCPF_REQUESTING | DCCPF_RESPOND)) {
+ if (atomic_read(&sk->sk_rmem_alloc) > 0)
+ mask |= POLLIN | POLLRDNORM;
+
+ if (!(sk->sk_shutdown & SEND_SHUTDOWN)) {
+ if (sk_stream_is_writeable(sk)) {
+ mask |= POLLOUT | POLLWRNORM;
+ } else { /* send SIGIO later */
+ set_bit(SOCK_ASYNC_NOSPACE,
+ &sk->sk_socket->flags);
+ set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
+
+ /* Race breaker. If space is freed after
+ * wspace test but before the flags are set,
+ * IO signal will be lost.
+ */
+ if (sk_stream_is_writeable(sk))
+ mask |= POLLOUT | POLLWRNORM;
+ }
+ }
+ }
+ return mask;
+}
+
+EXPORT_SYMBOL_GPL(dccp_poll);
+
+int dccp_ioctl(struct sock *sk, int cmd, unsigned long arg)
+{
+ int rc = -ENOTCONN;
+
+ lock_sock(sk);
+
+ if (sk->sk_state == DCCP_LISTEN)
+ goto out;
+
+ switch (cmd) {
+ case SIOCINQ: {
+ struct sk_buff *skb;
+ unsigned long amount = 0;
+
+ skb = skb_peek(&sk->sk_receive_queue);
+ if (skb != NULL) {
+ /*
+ * We will only return the amount of this packet since
+ * that is all that will be read.
+ */
+ amount = skb->len;
+ }
+ rc = put_user(amount, (int __user *)arg);
+ }
+ break;
+ default:
+ rc = -ENOIOCTLCMD;
+ break;
+ }
+out:
+ release_sock(sk);
+ return rc;
+}
+
+EXPORT_SYMBOL_GPL(dccp_ioctl);
+
+static int dccp_setsockopt_service(struct sock *sk, const __be32 service,
+ char __user *optval, unsigned int optlen)
+{
+ struct dccp_sock *dp = dccp_sk(sk);
+ struct dccp_service_list *sl = NULL;
+
+ if (service == DCCP_SERVICE_INVALID_VALUE ||
+ optlen > DCCP_SERVICE_LIST_MAX_LEN * sizeof(u32))
+ return -EINVAL;
+
+ if (optlen > sizeof(service)) {
+ sl = kmalloc(optlen, GFP_KERNEL);
+ if (sl == NULL)
+ return -ENOMEM;
+
+ sl->dccpsl_nr = optlen / sizeof(u32) - 1;
+ if (copy_from_user(sl->dccpsl_list,
+ optval + sizeof(service),
+ optlen - sizeof(service)) ||
+ dccp_list_has_service(sl, DCCP_SERVICE_INVALID_VALUE)) {
+ kfree(sl);
+ return -EFAULT;
+ }
+ }
+
+ lock_sock(sk);
+ dp->dccps_service = service;
+
+ kfree(dp->dccps_service_list);
+
+ dp->dccps_service_list = sl;
+ release_sock(sk);
+ return 0;
+}
+
+static int dccp_setsockopt_cscov(struct sock *sk, int cscov, bool rx)
+{
+ u8 *list, len;
+ int i, rc;
+
+ if (cscov < 0 || cscov > 15)
+ return -EINVAL;
+ /*
+ * Populate a list of permissible values, in the range cscov...15. This
+ * is necessary since feature negotiation of single values only works if
+ * both sides incidentally choose the same value. Since the list starts
+ * lowest-value first, negotiation will pick the smallest shared value.
+ */
+ if (cscov == 0)
+ return 0;
+ len = 16 - cscov;
+
+ list = kmalloc(len, GFP_KERNEL);
+ if (list == NULL)
+ return -ENOBUFS;
+
+ for (i = 0; i < len; i++)
+ list[i] = cscov++;
+
+ rc = dccp_feat_register_sp(sk, DCCPF_MIN_CSUM_COVER, rx, list, len);
+
+ if (rc == 0) {
+ if (rx)
+ dccp_sk(sk)->dccps_pcrlen = cscov;
+ else
+ dccp_sk(sk)->dccps_pcslen = cscov;
+ }
+ kfree(list);
+ return rc;
+}
+
+static int dccp_setsockopt_ccid(struct sock *sk, int type,
+ char __user *optval, unsigned int optlen)
+{
+ u8 *val;
+ int rc = 0;
+
+ if (optlen < 1 || optlen > DCCP_FEAT_MAX_SP_VALS)
+ return -EINVAL;
+
+ val = memdup_user(optval, optlen);
+ if (IS_ERR(val))
+ return PTR_ERR(val);
+
+ lock_sock(sk);
+ if (type == DCCP_SOCKOPT_TX_CCID || type == DCCP_SOCKOPT_CCID)
+ rc = dccp_feat_register_sp(sk, DCCPF_CCID, 1, val, optlen);
+
+ if (!rc && (type == DCCP_SOCKOPT_RX_CCID || type == DCCP_SOCKOPT_CCID))
+ rc = dccp_feat_register_sp(sk, DCCPF_CCID, 0, val, optlen);
+ release_sock(sk);
+
+ kfree(val);
+ return rc;
+}
+
+static int do_dccp_setsockopt(struct sock *sk, int level, int optname,
+ char __user *optval, unsigned int optlen)
+{
+ struct dccp_sock *dp = dccp_sk(sk);
+ int val, err = 0;
+
+ switch (optname) {
+ case DCCP_SOCKOPT_PACKET_SIZE:
+ DCCP_WARN("sockopt(PACKET_SIZE) is deprecated: fix your app\n");
+ return 0;
+ case DCCP_SOCKOPT_CHANGE_L:
+ case DCCP_SOCKOPT_CHANGE_R:
+ DCCP_WARN("sockopt(CHANGE_L/R) is deprecated: fix your app\n");
+ return 0;
+ case DCCP_SOCKOPT_CCID:
+ case DCCP_SOCKOPT_RX_CCID:
+ case DCCP_SOCKOPT_TX_CCID:
+ return dccp_setsockopt_ccid(sk, optname, optval, optlen);
+ }
+
+ if (optlen < (int)sizeof(int))
+ return -EINVAL;
+
+ if (get_user(val, (int __user *)optval))
+ return -EFAULT;
+
+ if (optname == DCCP_SOCKOPT_SERVICE)
+ return dccp_setsockopt_service(sk, val, optval, optlen);
+
+ lock_sock(sk);
+ switch (optname) {
+ case DCCP_SOCKOPT_SERVER_TIMEWAIT:
+ if (dp->dccps_role != DCCP_ROLE_SERVER)
+ err = -EOPNOTSUPP;
+ else
+ dp->dccps_server_timewait = (val != 0);
+ break;
+ case DCCP_SOCKOPT_SEND_CSCOV:
+ err = dccp_setsockopt_cscov(sk, val, false);
+ break;
+ case DCCP_SOCKOPT_RECV_CSCOV:
+ err = dccp_setsockopt_cscov(sk, val, true);
+ break;
+ case DCCP_SOCKOPT_QPOLICY_ID:
+ if (sk->sk_state != DCCP_CLOSED)
+ err = -EISCONN;
+ else if (val < 0 || val >= DCCPQ_POLICY_MAX)
+ err = -EINVAL;
+ else
+ dp->dccps_qpolicy = val;
+ break;
+ case DCCP_SOCKOPT_QPOLICY_TXQLEN:
+ if (val < 0)
+ err = -EINVAL;
+ else
+ dp->dccps_tx_qlen = val;
+ break;
+ default:
+ err = -ENOPROTOOPT;
+ break;
+ }
+ release_sock(sk);
+
+ return err;
+}
+
+int dccp_setsockopt(struct sock *sk, int level, int optname,
+ char __user *optval, unsigned int optlen)
+{
+ if (level != SOL_DCCP)
+ return inet_csk(sk)->icsk_af_ops->setsockopt(sk, level,
+ optname, optval,
+ optlen);
+ return do_dccp_setsockopt(sk, level, optname, optval, optlen);
+}
+
+EXPORT_SYMBOL_GPL(dccp_setsockopt);
+
+#ifdef CONFIG_COMPAT
+int compat_dccp_setsockopt(struct sock *sk, int level, int optname,
+ char __user *optval, unsigned int optlen)
+{
+ if (level != SOL_DCCP)
+ return inet_csk_compat_setsockopt(sk, level, optname,
+ optval, optlen);
+ return do_dccp_setsockopt(sk, level, optname, optval, optlen);
+}
+
+EXPORT_SYMBOL_GPL(compat_dccp_setsockopt);
+#endif
+
+static int dccp_getsockopt_service(struct sock *sk, int len,
+ __be32 __user *optval,
+ int __user *optlen)
+{
+ const struct dccp_sock *dp = dccp_sk(sk);
+ const struct dccp_service_list *sl;
+ int err = -ENOENT, slen = 0, total_len = sizeof(u32);
+
+ lock_sock(sk);
+ if ((sl = dp->dccps_service_list) != NULL) {
+ slen = sl->dccpsl_nr * sizeof(u32);
+ total_len += slen;
+ }
+
+ err = -EINVAL;
+ if (total_len > len)
+ goto out;
+
+ err = 0;
+ if (put_user(total_len, optlen) ||
+ put_user(dp->dccps_service, optval) ||
+ (sl != NULL && copy_to_user(optval + 1, sl->dccpsl_list, slen)))
+ err = -EFAULT;
+out:
+ release_sock(sk);
+ return err;
+}
+
+static int do_dccp_getsockopt(struct sock *sk, int level, int optname,
+ char __user *optval, int __user *optlen)
+{
+ struct dccp_sock *dp;
+ int val, len;
+
+ if (get_user(len, optlen))
+ return -EFAULT;
+
+ if (len < (int)sizeof(int))
+ return -EINVAL;
+
+ dp = dccp_sk(sk);
+
+ switch (optname) {
+ case DCCP_SOCKOPT_PACKET_SIZE:
+ DCCP_WARN("sockopt(PACKET_SIZE) is deprecated: fix your app\n");
+ return 0;
+ case DCCP_SOCKOPT_SERVICE:
+ return dccp_getsockopt_service(sk, len,
+ (__be32 __user *)optval, optlen);
+ case DCCP_SOCKOPT_GET_CUR_MPS:
+ val = dp->dccps_mss_cache;
+ break;
+ case DCCP_SOCKOPT_AVAILABLE_CCIDS:
+ return ccid_getsockopt_builtin_ccids(sk, len, optval, optlen);
+ case DCCP_SOCKOPT_TX_CCID:
+ val = ccid_get_current_tx_ccid(dp);
+ if (val < 0)
+ return -ENOPROTOOPT;
+ break;
+ case DCCP_SOCKOPT_RX_CCID:
+ val = ccid_get_current_rx_ccid(dp);
+ if (val < 0)
+ return -ENOPROTOOPT;
+ break;
+ case DCCP_SOCKOPT_SERVER_TIMEWAIT:
+ val = dp->dccps_server_timewait;
+ break;
+ case DCCP_SOCKOPT_SEND_CSCOV:
+ val = dp->dccps_pcslen;
+ break;
+ case DCCP_SOCKOPT_RECV_CSCOV:
+ val = dp->dccps_pcrlen;
+ break;
+ case DCCP_SOCKOPT_QPOLICY_ID:
+ val = dp->dccps_qpolicy;
+ break;
+ case DCCP_SOCKOPT_QPOLICY_TXQLEN:
+ val = dp->dccps_tx_qlen;
+ break;
+ case 128 ... 191:
+ return ccid_hc_rx_getsockopt(dp->dccps_hc_rx_ccid, sk, optname,
+ len, (u32 __user *)optval, optlen);
+ case 192 ... 255:
+ return ccid_hc_tx_getsockopt(dp->dccps_hc_tx_ccid, sk, optname,
+ len, (u32 __user *)optval, optlen);
+ default:
+ return -ENOPROTOOPT;
+ }
+
+ len = sizeof(val);
+ if (put_user(len, optlen) || copy_to_user(optval, &val, len))
+ return -EFAULT;
+
+ return 0;
+}
+
+int dccp_getsockopt(struct sock *sk, int level, int optname,
+ char __user *optval, int __user *optlen)
+{
+ if (level != SOL_DCCP)
+ return inet_csk(sk)->icsk_af_ops->getsockopt(sk, level,
+ optname, optval,
+ optlen);
+ return do_dccp_getsockopt(sk, level, optname, optval, optlen);
+}
+
+EXPORT_SYMBOL_GPL(dccp_getsockopt);
+
+#ifdef CONFIG_COMPAT
+int compat_dccp_getsockopt(struct sock *sk, int level, int optname,
+ char __user *optval, int __user *optlen)
+{
+ if (level != SOL_DCCP)
+ return inet_csk_compat_getsockopt(sk, level, optname,
+ optval, optlen);
+ return do_dccp_getsockopt(sk, level, optname, optval, optlen);
+}
+
+EXPORT_SYMBOL_GPL(compat_dccp_getsockopt);
+#endif
+
+static int dccp_msghdr_parse(struct msghdr *msg, struct sk_buff *skb)
+{
+ struct cmsghdr *cmsg;
+
+ /*
+ * Assign an (opaque) qpolicy priority value to skb->priority.
+ *
+ * We are overloading this skb field for use with the qpolicy subystem.
+ * The skb->priority is normally used for the SO_PRIORITY option, which
+ * is initialised from sk_priority. Since the assignment of sk_priority
+ * to skb->priority happens later (on layer 3), we overload this field
+ * for use with queueing priorities as long as the skb is on layer 4.
+ * The default priority value (if nothing is set) is 0.
+ */
+ skb->priority = 0;
+
+ for_each_cmsghdr(cmsg, msg) {
+ if (!CMSG_OK(msg, cmsg))
+ return -EINVAL;
+
+ if (cmsg->cmsg_level != SOL_DCCP)
+ continue;
+
+ if (cmsg->cmsg_type <= DCCP_SCM_QPOLICY_MAX &&
+ !dccp_qpolicy_param_ok(skb->sk, cmsg->cmsg_type))
+ return -EINVAL;
+
+ switch (cmsg->cmsg_type) {
+ case DCCP_SCM_PRIORITY:
+ if (cmsg->cmsg_len != CMSG_LEN(sizeof(__u32)))
+ return -EINVAL;
+ skb->priority = *(__u32 *)CMSG_DATA(cmsg);
+ break;
+ default:
+ return -EINVAL;
+ }
+ }
+ return 0;
+}
+
+int dccp_sendmsg(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);
+
+ if (dccp_qpolicy_full(sk)) {
+ rc = -EAGAIN;
+ goto out_release;
+ }
+
+ timeo = sock_sndtimeo(sk, noblock);
+
+ /*
+ * 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))
+ if ((rc = sk_stream_wait_connect(sk, &timeo)) != 0)
+ goto out_release;
+
+ 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_from_msg(skb_put(skb, len), msg, len);
+ if (rc != 0)
+ goto out_discard;
+
+ rc = dccp_msghdr_parse(msg, skb);
+ if (rc != 0)
+ goto out_discard;
+
+ dccp_qpolicy_push(sk, skb);
+ /*
+ * The xmit_timer is set if the TX CCID is rate-based and will expire
+ * when congestion control permits to release further packets into the
+ * network. Window-based CCIDs do not use this timer.
+ */
+ if (!timer_pending(&dp->dccps_xmit_timer))
+ dccp_write_xmit(sk);
+out_release:
+ release_sock(sk);
+ return rc ? : len;
+out_discard:
+ kfree_skb(skb);
+ goto out_release;
+}
+
+EXPORT_SYMBOL_GPL(dccp_sendmsg);
+
+int dccp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int nonblock,
+ int flags, int *addr_len)
+{
+ const struct dccp_hdr *dh;
+ long timeo;
+
+ lock_sock(sk);
+
+ if (sk->sk_state == DCCP_LISTEN) {
+ len = -ENOTCONN;
+ goto out;
+ }
+
+ timeo = sock_rcvtimeo(sk, nonblock);
+
+ do {
+ struct sk_buff *skb = skb_peek(&sk->sk_receive_queue);
+
+ if (skb == NULL)
+ goto verify_sock_status;
+
+ dh = dccp_hdr(skb);
+
+ switch (dh->dccph_type) {
+ case DCCP_PKT_DATA:
+ case DCCP_PKT_DATAACK:
+ goto found_ok_skb;
+
+ case DCCP_PKT_CLOSE:
+ case DCCP_PKT_CLOSEREQ:
+ if (!(flags & MSG_PEEK))
+ dccp_finish_passive_close(sk);
+ /* fall through */
+ case DCCP_PKT_RESET:
+ dccp_pr_debug("found fin (%s) ok!\n",
+ dccp_packet_name(dh->dccph_type));
+ len = 0;
+ goto found_fin_ok;
+ default:
+ dccp_pr_debug("packet_type=%s\n",
+ dccp_packet_name(dh->dccph_type));
+ sk_eat_skb(sk, skb);
+ }
+verify_sock_status:
+ if (sock_flag(sk, SOCK_DONE)) {
+ len = 0;
+ break;
+ }
+
+ if (sk->sk_err) {
+ len = sock_error(sk);
+ break;
+ }
+
+ if (sk->sk_shutdown & RCV_SHUTDOWN) {
+ len = 0;
+ break;
+ }
+
+ if (sk->sk_state == DCCP_CLOSED) {
+ if (!sock_flag(sk, SOCK_DONE)) {
+ /* This occurs when user tries to read
+ * from never connected socket.
+ */
+ len = -ENOTCONN;
+ break;
+ }
+ len = 0;
+ break;
+ }
+
+ if (!timeo) {
+ len = -EAGAIN;
+ break;
+ }
+
+ if (signal_pending(current)) {
+ len = sock_intr_errno(timeo);
+ break;
+ }
+
+ sk_wait_data(sk, &timeo);
+ continue;
+ found_ok_skb:
+ if (len > skb->len)
+ len = skb->len;
+ else if (len < skb->len)
+ msg->msg_flags |= MSG_TRUNC;
+
+ if (skb_copy_datagram_msg(skb, 0, msg, len)) {
+ /* Exception. Bailout! */
+ len = -EFAULT;
+ break;
+ }
+ if (flags & MSG_TRUNC)
+ len = skb->len;
+ found_fin_ok:
+ if (!(flags & MSG_PEEK))
+ sk_eat_skb(sk, skb);
+ break;
+ } while (1);
+out:
+ release_sock(sk);
+ return len;
+}
+
+EXPORT_SYMBOL_GPL(dccp_recvmsg);
+
+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, backlog);
+ if (err)
+ goto out;
+ }
+ sk->sk_max_ack_backlog = backlog;
+ err = 0;
+
+out:
+ release_sock(sk);
+ return err;
+}
+
+EXPORT_SYMBOL_GPL(inet_dccp_listen);
+
+static void dccp_terminate_connection(struct sock *sk)
+{
+ u8 next_state = DCCP_CLOSED;
+
+ switch (sk->sk_state) {
+ case DCCP_PASSIVE_CLOSE:
+ case DCCP_PASSIVE_CLOSEREQ:
+ dccp_finish_passive_close(sk);
+ break;
+ case DCCP_PARTOPEN:
+ dccp_pr_debug("Stop PARTOPEN timer (%p)\n", sk);
+ inet_csk_clear_xmit_timer(sk, ICSK_TIME_DACK);
+ /* fall through */
+ case DCCP_OPEN:
+ dccp_send_close(sk, 1);
+
+ if (dccp_sk(sk)->dccps_role == DCCP_ROLE_SERVER &&
+ !dccp_sk(sk)->dccps_server_timewait)
+ next_state = DCCP_ACTIVE_CLOSEREQ;
+ else
+ next_state = DCCP_CLOSING;
+ /* fall through */
+ default:
+ dccp_set_state(sk, next_state);
+ }
+}
+
+void dccp_close(struct sock *sk, long timeout)
+{
+ struct dccp_sock *dp = dccp_sk(sk);
+ struct sk_buff *skb;
+ u32 data_was_unread = 0;
+ int state;
+
+ 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;
+ }
+
+ sk_stop_timer(sk, &dp->dccps_xmit_timer);
+
+ /*
+ * 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!
+ */
+ while ((skb = __skb_dequeue(&sk->sk_receive_queue)) != NULL) {
+ data_was_unread += skb->len;
+ __kfree_skb(skb);
+ }
+
+ if (data_was_unread) {
+ /* Unread data was tossed, send an appropriate Reset Code */
+ DCCP_WARN("ABORT with %u bytes unread\n", data_was_unread);
+ dccp_send_reset(sk, DCCP_RESET_CODE_ABORTED);
+ dccp_set_state(sk, DCCP_CLOSED);
+ } else 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 (sk->sk_state != DCCP_CLOSED) {
+ /*
+ * Normal connection termination. May need to wait if there are
+ * still packets in the TX queue that are delayed by the CCID.
+ */
+ dccp_flush_write_queue(sk, &timeout);
+ dccp_terminate_connection(sk);
+ }
+
+ /*
+ * Flush write queue. This may be necessary in several cases:
+ * - we have been closed by the peer but still have application data;
+ * - abortive termination (unread data or zero linger time),
+ * - normal termination but queue could not be flushed within time limit
+ */
+ __skb_queue_purge(&sk->sk_write_queue);
+
+ sk_stream_wait_close(sk, timeout);
+
+adjudge_to_death:
+ state = sk->sk_state;
+ sock_hold(sk);
+ sock_orphan(sk);
+
+ /*
+ * It is the last release_sock in its life. It will remove backlog.
+ */
+ 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);
+ WARN_ON(sock_owned_by_user(sk));
+
+ percpu_counter_inc(sk->sk_prot->orphan_count);
+
+ /* Have we already been destroyed by a softirq or backlog? */
+ if (state != DCCP_CLOSED && sk->sk_state == DCCP_CLOSED)
+ goto out;
+
+ if (sk->sk_state == DCCP_CLOSED)
+ inet_csk_destroy_sock(sk);
+
+ /* Otherwise, socket is reprieved until protocol close. */
+
+out:
+ bh_unlock_sock(sk);
+ local_bh_enable();
+ sock_put(sk);
+}
+
+EXPORT_SYMBOL_GPL(dccp_close);
+
+void dccp_shutdown(struct sock *sk, int how)
+{
+ dccp_pr_debug("called shutdown(%x)\n", how);
+}
+
+EXPORT_SYMBOL_GPL(dccp_shutdown);
+
+static inline int __init dccp_mib_init(void)
+{
+ dccp_statistics = alloc_percpu(struct dccp_mib);
+ if (!dccp_statistics)
+ return -ENOMEM;
+ return 0;
+}
+
+static inline void dccp_mib_exit(void)
+{
+ free_percpu(dccp_statistics);
+}
+
+static int thash_entries;
+module_param(thash_entries, int, 0444);
+MODULE_PARM_DESC(thash_entries, "Number of ehash buckets");
+
+#ifdef CONFIG_IP_DCCP_DEBUG
+bool dccp_debug;
+module_param(dccp_debug, bool, 0644);
+MODULE_PARM_DESC(dccp_debug, "Enable debug messages");
+
+EXPORT_SYMBOL_GPL(dccp_debug);
+#endif
+
+static int __init dccp_init(void)
+{
+ unsigned long goal;
+ int ehash_order, bhash_order, i;
+ int rc;
+
+ BUILD_BUG_ON(sizeof(struct dccp_skb_cb) >
+ FIELD_SIZEOF(struct sk_buff, cb));
+ rc = percpu_counter_init(&dccp_orphan_count, 0, GFP_KERNEL);
+ if (rc)
+ goto out_fail;
+ rc = -ENOBUFS;
+ inet_hashinfo_init(&dccp_hashinfo);
+ dccp_hashinfo.bind_bucket_cachep =
+ kmem_cache_create("dccp_bind_bucket",
+ sizeof(struct inet_bind_bucket), 0,
+ SLAB_HWCACHE_ALIGN, NULL);
+ if (!dccp_hashinfo.bind_bucket_cachep)
+ goto out_free_percpu;
+
+ /*
+ * Size and allocate the main established and bind bucket
+ * hash tables.
+ *
+ * The methodology is similar to that of the buffer cache.
+ */
+ if (totalram_pages >= (128 * 1024))
+ goal = totalram_pages >> (21 - PAGE_SHIFT);
+ else
+ goal = totalram_pages >> (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 {
+ unsigned long hash_size = (1UL << ehash_order) * PAGE_SIZE /
+ sizeof(struct inet_ehash_bucket);
+
+ while (hash_size & (hash_size - 1))
+ hash_size--;
+ dccp_hashinfo.ehash_mask = hash_size - 1;
+ dccp_hashinfo.ehash = (struct inet_ehash_bucket *)
+ __get_free_pages(GFP_ATOMIC|__GFP_NOWARN, ehash_order);
+ } while (!dccp_hashinfo.ehash && --ehash_order > 0);
+
+ if (!dccp_hashinfo.ehash) {
+ DCCP_CRIT("Failed to allocate DCCP established hash table");
+ goto out_free_bind_bucket_cachep;
+ }
+
+ for (i = 0; i <= dccp_hashinfo.ehash_mask; i++)
+ INIT_HLIST_NULLS_HEAD(&dccp_hashinfo.ehash[i].chain, i);
+
+ if (inet_ehash_locks_alloc(&dccp_hashinfo))
+ goto out_free_dccp_ehash;
+
+ 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|__GFP_NOWARN, bhash_order);
+ } while (!dccp_hashinfo.bhash && --bhash_order >= 0);
+
+ if (!dccp_hashinfo.bhash) {
+ DCCP_CRIT("Failed to allocate DCCP bind hash table");
+ goto out_free_dccp_locks;
+ }
+
+ 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);
+ }
+
+ rc = dccp_mib_init();
+ if (rc)
+ goto out_free_dccp_bhash;
+
+ rc = dccp_ackvec_init();
+ if (rc)
+ goto out_free_dccp_mib;
+
+ rc = dccp_sysctl_init();
+ if (rc)
+ goto out_ackvec_exit;
+
+ rc = ccid_initialize_builtins();
+ if (rc)
+ goto out_sysctl_exit;
+
+ dccp_timestamping_init();
+
+ return 0;
+
+out_sysctl_exit:
+ dccp_sysctl_exit();
+out_ackvec_exit:
+ dccp_ackvec_exit();
+out_free_dccp_mib:
+ dccp_mib_exit();
+out_free_dccp_bhash:
+ free_pages((unsigned long)dccp_hashinfo.bhash, bhash_order);
+out_free_dccp_locks:
+ inet_ehash_locks_free(&dccp_hashinfo);
+out_free_dccp_ehash:
+ free_pages((unsigned long)dccp_hashinfo.ehash, ehash_order);
+out_free_bind_bucket_cachep:
+ kmem_cache_destroy(dccp_hashinfo.bind_bucket_cachep);
+out_free_percpu:
+ percpu_counter_destroy(&dccp_orphan_count);
+out_fail:
+ dccp_hashinfo.bhash = NULL;
+ dccp_hashinfo.ehash = NULL;
+ dccp_hashinfo.bind_bucket_cachep = NULL;
+ return rc;
+}
+
+static void __exit dccp_fini(void)
+{
+ ccid_cleanup_builtins();
+ dccp_mib_exit();
+ free_pages((unsigned long)dccp_hashinfo.bhash,
+ get_order(dccp_hashinfo.bhash_size *
+ sizeof(struct inet_bind_hashbucket)));
+ free_pages((unsigned long)dccp_hashinfo.ehash,
+ get_order((dccp_hashinfo.ehash_mask + 1) *
+ sizeof(struct inet_ehash_bucket)));
+ inet_ehash_locks_free(&dccp_hashinfo);
+ kmem_cache_destroy(dccp_hashinfo.bind_bucket_cachep);
+ dccp_ackvec_exit();
+ dccp_sysctl_exit();
+ percpu_counter_destroy(&dccp_orphan_count);
+}
+
+module_init(dccp_init);
+module_exit(dccp_fini);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Arnaldo Carvalho de Melo <acme@conectiva.com.br>");
+MODULE_DESCRIPTION("DCCP - Datagram Congestion Controlled Protocol");
Code Review / kvmfornfv.git / blobdiff