diff options
Diffstat (limited to 'net/rxrpc/connection.c')
| -rw-r--r-- | net/rxrpc/connection.c | 778 |
1 files changed, 778 insertions, 0 deletions
diff --git a/net/rxrpc/connection.c b/net/rxrpc/connection.c new file mode 100644 index 00000000000..61463c74f8c --- /dev/null +++ b/net/rxrpc/connection.c @@ -0,0 +1,778 @@ +/* connection.c: Rx connection routines + * + * Copyright (C) 2002 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#include <linux/sched.h> +#include <linux/slab.h> +#include <linux/module.h> +#include <rxrpc/rxrpc.h> +#include <rxrpc/transport.h> +#include <rxrpc/peer.h> +#include <rxrpc/connection.h> +#include <rxrpc/call.h> +#include <rxrpc/message.h> +#include <linux/udp.h> +#include <linux/ip.h> +#include <net/sock.h> +#include <asm/uaccess.h> +#include "internal.h" + +__RXACCT_DECL(atomic_t rxrpc_connection_count); + +LIST_HEAD(rxrpc_conns); +DECLARE_RWSEM(rxrpc_conns_sem); +unsigned long rxrpc_conn_timeout = 60 * 60; + +static void rxrpc_conn_do_timeout(struct rxrpc_connection *conn); + +static void __rxrpc_conn_timeout(rxrpc_timer_t *timer) +{ + struct rxrpc_connection *conn = + list_entry(timer, struct rxrpc_connection, timeout); + + _debug("Rx CONN TIMEOUT [%p{u=%d}]", conn, atomic_read(&conn->usage)); + + rxrpc_conn_do_timeout(conn); +} + +static const struct rxrpc_timer_ops rxrpc_conn_timer_ops = { + .timed_out = __rxrpc_conn_timeout, +}; + +/*****************************************************************************/ +/* + * create a new connection record + */ +static inline int __rxrpc_create_connection(struct rxrpc_peer *peer, + struct rxrpc_connection **_conn) +{ + struct rxrpc_connection *conn; + + _enter("%p",peer); + + /* allocate and initialise a connection record */ + conn = kmalloc(sizeof(struct rxrpc_connection), GFP_KERNEL); + if (!conn) { + _leave(" = -ENOMEM"); + return -ENOMEM; + } + + memset(conn, 0, sizeof(struct rxrpc_connection)); + atomic_set(&conn->usage, 1); + + INIT_LIST_HEAD(&conn->link); + INIT_LIST_HEAD(&conn->id_link); + init_waitqueue_head(&conn->chanwait); + spin_lock_init(&conn->lock); + rxrpc_timer_init(&conn->timeout, &rxrpc_conn_timer_ops); + + do_gettimeofday(&conn->atime); + conn->mtu_size = 1024; + conn->peer = peer; + conn->trans = peer->trans; + + __RXACCT(atomic_inc(&rxrpc_connection_count)); + *_conn = conn; + _leave(" = 0 (%p)", conn); + + return 0; +} /* end __rxrpc_create_connection() */ + +/*****************************************************************************/ +/* + * create a new connection record for outgoing connections + */ +int rxrpc_create_connection(struct rxrpc_transport *trans, + __be16 port, + __be32 addr, + uint16_t service_id, + void *security, + struct rxrpc_connection **_conn) +{ + struct rxrpc_connection *candidate, *conn; + struct rxrpc_peer *peer; + struct list_head *_p; + __be32 connid; + int ret; + + _enter("%p{%hu},%u,%hu", trans, trans->port, ntohs(port), service_id); + + /* get a peer record */ + ret = rxrpc_peer_lookup(trans, addr, &peer); + if (ret < 0) { + _leave(" = %d", ret); + return ret; + } + + /* allocate and initialise a connection record */ + ret = __rxrpc_create_connection(peer, &candidate); + if (ret < 0) { + rxrpc_put_peer(peer); + _leave(" = %d", ret); + return ret; + } + + /* fill in the specific bits */ + candidate->addr.sin_family = AF_INET; + candidate->addr.sin_port = port; + candidate->addr.sin_addr.s_addr = addr; + + candidate->in_epoch = rxrpc_epoch; + candidate->out_epoch = rxrpc_epoch; + candidate->in_clientflag = 0; + candidate->out_clientflag = RXRPC_CLIENT_INITIATED; + candidate->service_id = htons(service_id); + + /* invent a unique connection ID */ + write_lock(&peer->conn_idlock); + + try_next_id: + connid = htonl(peer->conn_idcounter & RXRPC_CIDMASK); + peer->conn_idcounter += RXRPC_MAXCALLS; + + list_for_each(_p, &peer->conn_idlist) { + conn = list_entry(_p, struct rxrpc_connection, id_link); + if (connid == conn->conn_id) + goto try_next_id; + if (connid > conn->conn_id) + break; + } + + _debug("selected candidate conn ID %x.%u", + ntohl(peer->addr.s_addr), ntohl(connid)); + + candidate->conn_id = connid; + list_add_tail(&candidate->id_link, _p); + + write_unlock(&peer->conn_idlock); + + /* attach to peer */ + candidate->peer = peer; + + write_lock(&peer->conn_lock); + + /* search the peer's transport graveyard list */ + spin_lock(&peer->conn_gylock); + list_for_each(_p, &peer->conn_graveyard) { + conn = list_entry(_p, struct rxrpc_connection, link); + if (conn->addr.sin_port == candidate->addr.sin_port && + conn->security_ix == candidate->security_ix && + conn->service_id == candidate->service_id && + conn->in_clientflag == 0) + goto found_in_graveyard; + } + spin_unlock(&peer->conn_gylock); + + /* pick the new candidate */ + _debug("created connection: {%08x} [out]", ntohl(candidate->conn_id)); + atomic_inc(&peer->conn_count); + conn = candidate; + candidate = NULL; + + make_active: + list_add_tail(&conn->link, &peer->conn_active); + write_unlock(&peer->conn_lock); + + if (candidate) { + write_lock(&peer->conn_idlock); + list_del(&candidate->id_link); + write_unlock(&peer->conn_idlock); + + __RXACCT(atomic_dec(&rxrpc_connection_count)); + kfree(candidate); + } + else { + down_write(&rxrpc_conns_sem); + list_add_tail(&conn->proc_link, &rxrpc_conns); + up_write(&rxrpc_conns_sem); + } + + *_conn = conn; + _leave(" = 0 (%p)", conn); + + return 0; + + /* handle resurrecting a connection from the graveyard */ + found_in_graveyard: + _debug("resurrecting connection: {%08x} [out]", ntohl(conn->conn_id)); + rxrpc_get_connection(conn); + rxrpc_krxtimod_del_timer(&conn->timeout); + list_del_init(&conn->link); + spin_unlock(&peer->conn_gylock); + goto make_active; +} /* end rxrpc_create_connection() */ + +/*****************************************************************************/ +/* + * lookup the connection for an incoming packet + * - create a new connection record for unrecorded incoming connections + */ +int rxrpc_connection_lookup(struct rxrpc_peer *peer, + struct rxrpc_message *msg, + struct rxrpc_connection **_conn) +{ + struct rxrpc_connection *conn, *candidate = NULL; + struct list_head *_p; + int ret, fresh = 0; + __be32 x_epoch, x_connid; + __be16 x_port, x_servid; + __u32 x_secix; + u8 x_clflag; + + _enter("%p{{%hu}},%u,%hu", + peer, + peer->trans->port, + ntohs(msg->pkt->h.uh->source), + ntohs(msg->hdr.serviceId)); + + x_port = msg->pkt->h.uh->source; + x_epoch = msg->hdr.epoch; + x_clflag = msg->hdr.flags & RXRPC_CLIENT_INITIATED; + x_connid = htonl(ntohl(msg->hdr.cid) & RXRPC_CIDMASK); + x_servid = msg->hdr.serviceId; + x_secix = msg->hdr.securityIndex; + + /* [common case] search the transport's active list first */ + read_lock(&peer->conn_lock); + list_for_each(_p, &peer->conn_active) { + conn = list_entry(_p, struct rxrpc_connection, link); + if (conn->addr.sin_port == x_port && + conn->in_epoch == x_epoch && + conn->conn_id == x_connid && + conn->security_ix == x_secix && + conn->service_id == x_servid && + conn->in_clientflag == x_clflag) + goto found_active; + } + read_unlock(&peer->conn_lock); + + /* [uncommon case] not active + * - create a candidate for a new record if an inbound connection + * - only examine the graveyard for an outbound connection + */ + if (x_clflag) { + ret = __rxrpc_create_connection(peer, &candidate); + if (ret < 0) { + _leave(" = %d", ret); + return ret; + } + + /* fill in the specifics */ + candidate->addr.sin_family = AF_INET; + candidate->addr.sin_port = x_port; + candidate->addr.sin_addr.s_addr = msg->pkt->nh.iph->saddr; + candidate->in_epoch = x_epoch; + candidate->out_epoch = x_epoch; + candidate->in_clientflag = RXRPC_CLIENT_INITIATED; + candidate->out_clientflag = 0; + candidate->conn_id = x_connid; + candidate->service_id = x_servid; + candidate->security_ix = x_secix; + } + + /* search the active list again, just in case it appeared whilst we + * were busy */ + write_lock(&peer->conn_lock); + list_for_each(_p, &peer->conn_active) { + conn = list_entry(_p, struct rxrpc_connection, link); + if (conn->addr.sin_port == x_port && + conn->in_epoch == x_epoch && + conn->conn_id == x_connid && + conn->security_ix == x_secix && + conn->service_id == x_servid && + conn->in_clientflag == x_clflag) + goto found_active_second_chance; + } + + /* search the transport's graveyard list */ + spin_lock(&peer->conn_gylock); + list_for_each(_p, &peer->conn_graveyard) { + conn = list_entry(_p, struct rxrpc_connection, link); + if (conn->addr.sin_port == x_port && + conn->in_epoch == x_epoch && + conn->conn_id == x_connid && + conn->security_ix == x_secix && + conn->service_id == x_servid && + conn->in_clientflag == x_clflag) + goto found_in_graveyard; + } + spin_unlock(&peer->conn_gylock); + + /* outbound connections aren't created here */ + if (!x_clflag) { + write_unlock(&peer->conn_lock); + _leave(" = -ENOENT"); + return -ENOENT; + } + + /* we can now add the new candidate to the list */ + _debug("created connection: {%08x} [in]", ntohl(candidate->conn_id)); + rxrpc_get_peer(peer); + conn = candidate; + candidate = NULL; + atomic_inc(&peer->conn_count); + fresh = 1; + + make_active: + list_add_tail(&conn->link, &peer->conn_active); + + success_uwfree: + write_unlock(&peer->conn_lock); + + if (candidate) { + write_lock(&peer->conn_idlock); + list_del(&candidate->id_link); + write_unlock(&peer->conn_idlock); + + __RXACCT(atomic_dec(&rxrpc_connection_count)); + kfree(candidate); + } + + if (fresh) { + down_write(&rxrpc_conns_sem); + list_add_tail(&conn->proc_link, &rxrpc_conns); + up_write(&rxrpc_conns_sem); + } + + success: + *_conn = conn; + _leave(" = 0 (%p)", conn); + return 0; + + /* handle the connection being found in the active list straight off */ + found_active: + rxrpc_get_connection(conn); + read_unlock(&peer->conn_lock); + goto success; + + /* handle resurrecting a connection from the graveyard */ + found_in_graveyard: + _debug("resurrecting connection: {%08x} [in]", ntohl(conn->conn_id)); + rxrpc_get_peer(peer); + rxrpc_get_connection(conn); + rxrpc_krxtimod_del_timer(&conn->timeout); + list_del_init(&conn->link); + spin_unlock(&peer->conn_gylock); + goto make_active; + + /* handle finding the connection on the second time through the active + * list */ + found_active_second_chance: + rxrpc_get_connection(conn); + goto success_uwfree; + +} /* end rxrpc_connection_lookup() */ + +/*****************************************************************************/ +/* + * finish using a connection record + * - it will be transferred to the peer's connection graveyard when refcount + * reaches 0 + */ +void rxrpc_put_connection(struct rxrpc_connection *conn) +{ + struct rxrpc_peer *peer; + + if (!conn) + return; + + _enter("%p{u=%d p=%hu}", + conn, atomic_read(&conn->usage), ntohs(conn->addr.sin_port)); + + peer = conn->peer; + spin_lock(&peer->conn_gylock); + + /* sanity check */ + if (atomic_read(&conn->usage) <= 0) + BUG(); + + if (likely(!atomic_dec_and_test(&conn->usage))) { + spin_unlock(&peer->conn_gylock); + _leave(""); + return; + } + + /* move to graveyard queue */ + _debug("burying connection: {%08x}", ntohl(conn->conn_id)); + list_del(&conn->link); + list_add_tail(&conn->link, &peer->conn_graveyard); + + rxrpc_krxtimod_add_timer(&conn->timeout, rxrpc_conn_timeout * HZ); + + spin_unlock(&peer->conn_gylock); + + rxrpc_put_peer(conn->peer); + + _leave(" [killed]"); +} /* end rxrpc_put_connection() */ + +/*****************************************************************************/ +/* + * free a connection record + */ +static void rxrpc_conn_do_timeout(struct rxrpc_connection *conn) +{ + struct rxrpc_peer *peer; + + _enter("%p{u=%d p=%hu}", + conn, atomic_read(&conn->usage), ntohs(conn->addr.sin_port)); + + peer = conn->peer; + + if (atomic_read(&conn->usage) < 0) + BUG(); + + /* remove from graveyard if still dead */ + spin_lock(&peer->conn_gylock); + if (atomic_read(&conn->usage) == 0) { + list_del_init(&conn->link); + } + else { + conn = NULL; + } + spin_unlock(&peer->conn_gylock); + + if (!conn) { + _leave(""); + return; /* resurrected */ + } + + _debug("--- Destroying Connection %p{%08x} ---", + conn, ntohl(conn->conn_id)); + + down_write(&rxrpc_conns_sem); + list_del(&conn->proc_link); + up_write(&rxrpc_conns_sem); + + write_lock(&peer->conn_idlock); + list_del(&conn->id_link); + write_unlock(&peer->conn_idlock); + + __RXACCT(atomic_dec(&rxrpc_connection_count)); + kfree(conn); + + /* if the graveyard is now empty, wake up anyone waiting for that */ + if (atomic_dec_and_test(&peer->conn_count)) + wake_up(&peer->conn_gy_waitq); + + _leave(" [destroyed]"); +} /* end rxrpc_conn_do_timeout() */ + +/*****************************************************************************/ +/* + * clear all connection records from a peer endpoint + */ +void rxrpc_conn_clearall(struct rxrpc_peer *peer) +{ + DECLARE_WAITQUEUE(myself, current); + + struct rxrpc_connection *conn; + int err; + + _enter("%p", peer); + + /* there shouldn't be any active conns remaining */ + if (!list_empty(&peer->conn_active)) + BUG(); + + /* manually timeout all conns in the graveyard */ + spin_lock(&peer->conn_gylock); + while (!list_empty(&peer->conn_graveyard)) { + conn = list_entry(peer->conn_graveyard.next, + struct rxrpc_connection, link); + err = rxrpc_krxtimod_del_timer(&conn->timeout); + spin_unlock(&peer->conn_gylock); + + if (err == 0) + rxrpc_conn_do_timeout(conn); + + spin_lock(&peer->conn_gylock); + } + spin_unlock(&peer->conn_gylock); + + /* wait for the the conn graveyard to be completely cleared */ + set_current_state(TASK_UNINTERRUPTIBLE); + add_wait_queue(&peer->conn_gy_waitq, &myself); + + while (atomic_read(&peer->conn_count) != 0) { + schedule(); + set_current_state(TASK_UNINTERRUPTIBLE); + } + + remove_wait_queue(&peer->conn_gy_waitq, &myself); + set_current_state(TASK_RUNNING); + + _leave(""); +} /* end rxrpc_conn_clearall() */ + +/*****************************************************************************/ +/* + * allocate and prepare a message for sending out through the transport + * endpoint + */ +int rxrpc_conn_newmsg(struct rxrpc_connection *conn, + struct rxrpc_call *call, + uint8_t type, + int dcount, + struct kvec diov[], + int alloc_flags, + struct rxrpc_message **_msg) +{ + struct rxrpc_message *msg; + int loop; + + _enter("%p{%d},%p,%u", conn, ntohs(conn->addr.sin_port), call, type); + + if (dcount > 3) { + _leave(" = -EINVAL"); + return -EINVAL; + } + + msg = kmalloc(sizeof(struct rxrpc_message), alloc_flags); + if (!msg) { + _leave(" = -ENOMEM"); + return -ENOMEM; + } + + memset(msg, 0, sizeof(*msg)); + atomic_set(&msg->usage, 1); + + INIT_LIST_HEAD(&msg->link); + + msg->state = RXRPC_MSG_PREPARED; + + msg->hdr.epoch = conn->out_epoch; + msg->hdr.cid = conn->conn_id | (call ? call->chan_ix : 0); + msg->hdr.callNumber = call ? call->call_id : 0; + msg->hdr.type = type; + msg->hdr.flags = conn->out_clientflag; + msg->hdr.securityIndex = conn->security_ix; + msg->hdr.serviceId = conn->service_id; + + /* generate sequence numbers for data packets */ + if (call) { + switch (type) { + case RXRPC_PACKET_TYPE_DATA: + msg->seq = ++call->snd_seq_count; + msg->hdr.seq = htonl(msg->seq); + break; + case RXRPC_PACKET_TYPE_ACK: + /* ACK sequence numbers are complicated. The following + * may be wrong: + * - jumbo packet ACKs should have a seq number + * - normal ACKs should not + */ + default: + break; + } + } + + msg->dcount = dcount + 1; + msg->dsize = sizeof(msg->hdr); + msg->data[0].iov_len = sizeof(msg->hdr); + msg->data[0].iov_base = &msg->hdr; + + for (loop=0; loop < dcount; loop++) { + msg->dsize += diov[loop].iov_len; + msg->data[loop+1].iov_len = diov[loop].iov_len; + msg->data[loop+1].iov_base = diov[loop].iov_base; + } + + __RXACCT(atomic_inc(&rxrpc_message_count)); + *_msg = msg; + _leave(" = 0 (%p) #%d", msg, atomic_read(&rxrpc_message_count)); + return 0; +} /* end rxrpc_conn_newmsg() */ + +/*****************************************************************************/ +/* + * free a message + */ +void __rxrpc_put_message(struct rxrpc_message *msg) +{ + int loop; + + _enter("%p #%d", msg, atomic_read(&rxrpc_message_count)); + + if (msg->pkt) + kfree_skb(msg->pkt); + rxrpc_put_connection(msg->conn); + + for (loop = 0; loop < 8; loop++) + if (test_bit(loop, &msg->dfree)) + kfree(msg->data[loop].iov_base); + + __RXACCT(atomic_dec(&rxrpc_message_count)); + kfree(msg); + + _leave(""); +} /* end __rxrpc_put_message() */ + +/*****************************************************************************/ +/* + * send a message out through the transport endpoint + */ +int rxrpc_conn_sendmsg(struct rxrpc_connection *conn, + struct rxrpc_message *msg) +{ + struct msghdr msghdr; + int ret; + + _enter("%p{%d}", conn, ntohs(conn->addr.sin_port)); + + /* fill in some fields in the header */ + spin_lock(&conn->lock); + msg->hdr.serial = htonl(++conn->serial_counter); + msg->rttdone = 0; + spin_unlock(&conn->lock); + + /* set up the message to be transmitted */ + msghdr.msg_name = &conn->addr; + msghdr.msg_namelen = sizeof(conn->addr); + msghdr.msg_control = NULL; + msghdr.msg_controllen = 0; + msghdr.msg_flags = MSG_CONFIRM | MSG_DONTWAIT; + + _net("Sending message type %d of %Zd bytes to %08x:%d", + msg->hdr.type, + msg->dsize, + ntohl(conn->addr.sin_addr.s_addr), + ntohs(conn->addr.sin_port)); + + /* send the message */ + ret = kernel_sendmsg(conn->trans->socket, &msghdr, + msg->data, msg->dcount, msg->dsize); + if (ret < 0) { + msg->state = RXRPC_MSG_ERROR; + } else { + msg->state = RXRPC_MSG_SENT; + ret = 0; + + spin_lock(&conn->lock); + do_gettimeofday(&conn->atime); + msg->stamp = conn->atime; + spin_unlock(&conn->lock); + } + + _leave(" = %d", ret); + + return ret; +} /* end rxrpc_conn_sendmsg() */ + +/*****************************************************************************/ +/* + * deal with a subsequent call packet + */ +int rxrpc_conn_receive_call_packet(struct rxrpc_connection *conn, + struct rxrpc_call *call, + struct rxrpc_message *msg) +{ + struct rxrpc_message *pmsg; + struct list_head *_p; + unsigned cix, seq; + int ret = 0; + + _enter("%p,%p,%p", conn, call, msg); + + if (!call) { + cix = ntohl(msg->hdr.cid) & RXRPC_CHANNELMASK; + + spin_lock(&conn->lock); + call = conn->channels[cix]; + + if (!call || call->call_id != msg->hdr.callNumber) { + spin_unlock(&conn->lock); + rxrpc_trans_immediate_abort(conn->trans, msg, -ENOENT); + goto out; + } + else { + rxrpc_get_call(call); + spin_unlock(&conn->lock); + } + } + else { + rxrpc_get_call(call); + } + + _proto("Received packet %%%u [%u] on call %hu:%u:%u", + ntohl(msg->hdr.serial), + ntohl(msg->hdr.seq), + ntohs(msg->hdr.serviceId), + ntohl(conn->conn_id), + ntohl(call->call_id)); + + call->pkt_rcv_count++; + + if (msg->pkt->dst && msg->pkt->dst->dev) + conn->peer->if_mtu = + msg->pkt->dst->dev->mtu - + msg->pkt->dst->dev->hard_header_len; + + /* queue on the call in seq order */ + rxrpc_get_message(msg); + seq = msg->seq; + + spin_lock(&call->lock); + list_for_each(_p, &call->rcv_receiveq) { + pmsg = list_entry(_p, struct rxrpc_message, link); + if (pmsg->seq > seq) + break; + } + list_add_tail(&msg->link, _p); + + /* reset the activity timeout */ + call->flags |= RXRPC_CALL_RCV_PKT; + mod_timer(&call->rcv_timeout,jiffies + rxrpc_call_rcv_timeout * HZ); + + spin_unlock(&call->lock); + + rxrpc_krxiod_queue_call(call); + + rxrpc_put_call(call); + out: + _leave(" = %d", ret); + return ret; +} /* end rxrpc_conn_receive_call_packet() */ + +/*****************************************************************************/ +/* + * handle an ICMP error being applied to a connection + */ +void rxrpc_conn_handle_error(struct rxrpc_connection *conn, + int local, int errno) +{ + struct rxrpc_call *calls[4]; + int loop; + + _enter("%p{%d},%d", conn, ntohs(conn->addr.sin_port), errno); + + /* get a ref to all my calls in one go */ + memset(calls, 0, sizeof(calls)); + spin_lock(&conn->lock); + + for (loop = 3; loop >= 0; loop--) { + if (conn->channels[loop]) { + calls[loop] = conn->channels[loop]; + rxrpc_get_call(calls[loop]); + } + } + + spin_unlock(&conn->lock); + + /* now kick them all */ + for (loop = 3; loop >= 0; loop--) { + if (calls[loop]) { + rxrpc_call_handle_error(calls[loop], local, errno); + rxrpc_put_call(calls[loop]); + } + } + + _leave(""); +} /* end rxrpc_conn_handle_error() */ |