Adding upstream version 6.1.76.upstream/6.1.76

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1290 insertions, 0 deletions

diff --git a/net/dccp/proto.c b/net/dccp/proto.c
new file mode 100644
index 000000000..c522c76a9
--- /dev/null
+++ b/net/dccp/proto.c
@@ -0,0 +1,1290 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ *  net/dccp/proto.c
+ *
+ *  An implementation of the DCCP protocol
+ *  Arnaldo Carvalho de Melo <acme@conectiva.com.br>
+ */
+
+#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/inet_common.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 CREATE_TRACE_POINTS
+#include "trace.h"
+
+DEFINE_SNMP_STAT(struct dccp_mib, dccp_statistics) __read_mostly;
+
+EXPORT_SYMBOL_GPL(dccp_statistics);
+
+DEFINE_PER_CPU(unsigned int, dccp_orphan_count);
+EXPORT_PER_CPU_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);
+		fallthrough;
+	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.
+	 */
+	inet_sk_set_state(sk, 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);
+
+void dccp_destruct_common(struct sock *sk)
+{
+	struct dccp_sock *dp = dccp_sk(sk);
+
+	ccid_hc_tx_delete(dp->dccps_hc_tx_ccid, sk);
+	dp->dccps_hc_tx_ccid = NULL;
+}
+EXPORT_SYMBOL_GPL(dccp_destruct_common);
+
+static void dccp_sk_destruct(struct sock *sk)
+{
+	dccp_destruct_common(sk);
+	inet_sock_destruct(sk);
+}
+
+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;
+	sk->sk_destruct		= dccp_sk_destruct;
+	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);
+
+	__skb_queue_purge(&sk->sk_write_queue);
+	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);
+	dp->dccps_hc_rx_ccid = NULL;
+
+	/* clean up feature negotiation state */
+	dccp_feat_list_purge(&dp->dccps_featneg);
+}
+
+EXPORT_SYMBOL_GPL(dccp_destroy_sock);
+
+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);
+	struct dccp_sock *dp = dccp_sk(sk);
+	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);
+	ccid_hc_rx_delete(dp->dccps_hc_rx_ccid, sk);
+	dp->dccps_hc_rx_ccid = NULL;
+
+	__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;
+
+	inet_bhash2_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_error_report(sk);
+	return 0;
+}
+
+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.
+ */
+__poll_t dccp_poll(struct file *file, struct socket *sock,
+		       poll_table *wait)
+{
+	struct sock *sk = sock->sk;
+	__poll_t mask;
+	u8 shutdown;
+	int state;
+
+	sock_poll_wait(file, sock, wait);
+
+	state = inet_sk_state_load(sk);
+	if (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 (READ_ONCE(sk->sk_err))
+		mask = EPOLLERR;
+	shutdown = READ_ONCE(sk->sk_shutdown);
+
+	if (shutdown == SHUTDOWN_MASK || state == DCCP_CLOSED)
+		mask |= EPOLLHUP;
+	if (shutdown & RCV_SHUTDOWN)
+		mask |= EPOLLIN | EPOLLRDNORM | EPOLLRDHUP;
+
+	/* Connected? */
+	if ((1 << state) & ~(DCCPF_REQUESTING | DCCPF_RESPOND)) {
+		if (atomic_read(&sk->sk_rmem_alloc) > 0)
+			mask |= EPOLLIN | EPOLLRDNORM;
+
+		if (!(shutdown & SEND_SHUTDOWN)) {
+			if (sk_stream_is_writeable(sk)) {
+				mask |= EPOLLOUT | EPOLLWRNORM;
+			} else {  /* send SIGIO later */
+				sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
+				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 |= EPOLLOUT | EPOLLWRNORM;
+			}
+		}
+	}
+	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 SIOCOUTQ: {
+		int amount = sk_wmem_alloc_get(sk);
+		/* Using sk_wmem_alloc here because sk_wmem_queued is not used by DCCP and
+		 * always 0, comparably to UDP.
+		 */
+
+		rc = put_user(amount, (int __user *)arg);
+	}
+		break;
+	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,
+				   sockptr_t 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_sockptr_offset(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,
+				sockptr_t optval, unsigned int optlen)
+{
+	u8 *val;
+	int rc = 0;
+
+	if (optlen < 1 || optlen > DCCP_FEAT_MAX_SP_VALS)
+		return -EINVAL;
+
+	val = memdup_sockptr(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,
+		sockptr_t 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 (copy_from_sockptr(&val, optval, sizeof(int)))
+		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, sockptr_t 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);
+
+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 = READ_ONCE(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);
+
+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;
+
+	trace_dccp_probe(sk, len);
+
+	if (len > READ_ONCE(dp->dccps_mss_cache))
+		return -EMSGSIZE;
+
+	lock_sock(sk);
+
+	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;
+
+	if (dccp_qpolicy_full(sk)) {
+		rc = -EAGAIN;
+		goto out_discard;
+	}
+
+	if (sk->sk_state == DCCP_CLOSED) {
+		rc = -ENOTCONN;
+		goto out_discard;
+	}
+
+	/* We need to check dccps_mss_cache after socket is locked. */
+	if (len > dp->dccps_mss_cache) {
+		rc = -EMSGSIZE;
+		goto out_discard;
+	}
+
+	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 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, flags & MSG_DONTWAIT);
+
+	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);
+			fallthrough;
+		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, NULL);
+		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;
+
+	WRITE_ONCE(sk->sk_max_ack_backlog, backlog);
+	/* Really, if the socket is already in listen state
+	 * we can only allow the backlog to be adjusted.
+	 */
+	if (old_state != DCCP_LISTEN) {
+		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)) {
+			err = -EPROTO;
+			goto out;
+		}
+
+		err = inet_csk_listen_start(sk);
+		if (err)
+			goto out;
+	}
+	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);
+		fallthrough;
+	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;
+		fallthrough;
+	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 socket has been already reset kill it. */
+	if (sk->sk_state == DCCP_CLOSED)
+		goto adjudge_to_death;
+
+	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));
+
+	this_cpu_inc(dccp_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;
+	unsigned long nr_pages = totalram_pages();
+	int ehash_order, bhash_order, i;
+	int rc;
+
+	BUILD_BUG_ON(sizeof(struct dccp_skb_cb) >
+		     sizeof_field(struct sk_buff, cb));
+	rc = inet_hashinfo2_init_mod(&dccp_hashinfo);
+	if (rc)
+		goto out_fail;
+	rc = -ENOBUFS;
+	dccp_hashinfo.bind_bucket_cachep =
+		kmem_cache_create("dccp_bind_bucket",
+				  sizeof(struct inet_bind_bucket), 0,
+				  SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT, NULL);
+	if (!dccp_hashinfo.bind_bucket_cachep)
+		goto out_free_hashinfo2;
+	dccp_hashinfo.bind2_bucket_cachep =
+		kmem_cache_create("dccp_bind2_bucket",
+				  sizeof(struct inet_bind2_bucket), 0,
+				  SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT, NULL);
+	if (!dccp_hashinfo.bind2_bucket_cachep)
+		goto out_free_bind_bucket_cachep;
+
+	/*
+	 * Size and allocate the main established and bind bucket
+	 * hash tables.
+	 *
+	 * The methodology is similar to that of the buffer cache.
+	 */
+	if (nr_pages >= (128 * 1024))
+		goal = nr_pages >> (21 - PAGE_SHIFT);
+	else
+		goal = nr_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_bind2_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;
+	}
+
+	dccp_hashinfo.bhash2 = (struct inet_bind_hashbucket *)
+		__get_free_pages(GFP_ATOMIC | __GFP_NOWARN, bhash_order);
+
+	if (!dccp_hashinfo.bhash2) {
+		DCCP_CRIT("Failed to allocate DCCP bind2 hash table");
+		goto out_free_dccp_bhash;
+	}
+
+	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);
+		spin_lock_init(&dccp_hashinfo.bhash2[i].lock);
+		INIT_HLIST_HEAD(&dccp_hashinfo.bhash2[i].chain);
+	}
+
+	dccp_hashinfo.pernet = false;
+
+	rc = dccp_mib_init();
+	if (rc)
+		goto out_free_dccp_bhash2;
+
+	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_bhash2:
+	free_pages((unsigned long)dccp_hashinfo.bhash2, bhash_order);
+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_bind2_bucket_cachep:
+	kmem_cache_destroy(dccp_hashinfo.bind2_bucket_cachep);
+out_free_bind_bucket_cachep:
+	kmem_cache_destroy(dccp_hashinfo.bind_bucket_cachep);
+out_free_hashinfo2:
+	inet_hashinfo2_free_mod(&dccp_hashinfo);
+out_fail:
+	dccp_hashinfo.bhash = NULL;
+	dccp_hashinfo.bhash2 = NULL;
+	dccp_hashinfo.ehash = NULL;
+	dccp_hashinfo.bind_bucket_cachep = NULL;
+	dccp_hashinfo.bind2_bucket_cachep = NULL;
+	return rc;
+}
+
+static void __exit dccp_fini(void)
+{
+	int bhash_order = get_order(dccp_hashinfo.bhash_size *
+				    sizeof(struct inet_bind_hashbucket));
+
+	ccid_cleanup_builtins();
+	dccp_mib_exit();
+	free_pages((unsigned long)dccp_hashinfo.bhash, bhash_order);
+	free_pages((unsigned long)dccp_hashinfo.bhash2, bhash_order);
+	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();
+	inet_hashinfo2_free_mod(&dccp_hashinfo);
+}
+
+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");