diff options
Diffstat (limited to 'net/phonet')
| -rw-r--r-- | net/phonet/Makefile | 4 | ||||
| -rw-r--r-- | net/phonet/af_phonet.c | 3 | ||||
| -rw-r--r-- | net/phonet/pep.c | 908 |
3 files changed, 914 insertions, 1 deletions
diff --git a/net/phonet/Makefile b/net/phonet/Makefile index ae9c3ed5be83..505df2a04a85 100644 --- a/net/phonet/Makefile +++ b/net/phonet/Makefile @@ -1,4 +1,4 @@ -obj-$(CONFIG_PHONET) += phonet.o +obj-$(CONFIG_PHONET) += phonet.o pn_pep.o phonet-objs := \ pn_dev.o \ @@ -7,3 +7,5 @@ phonet-objs := \ datagram.o \ sysctl.o \ af_phonet.o + +pn_pep-objs := pep.o diff --git a/net/phonet/af_phonet.c b/net/phonet/af_phonet.c index 0a74aeaf5adf..9e9c6fce11aa 100644 --- a/net/phonet/af_phonet.c +++ b/net/phonet/af_phonet.c @@ -58,6 +58,9 @@ static int pn_socket_create(struct net *net, struct socket *sock, int protocol) case SOCK_DGRAM: protocol = PN_PROTO_PHONET; break; + case SOCK_SEQPACKET: + protocol = PN_PROTO_PIPE; + break; default: return -EPROTONOSUPPORT; } diff --git a/net/phonet/pep.c b/net/phonet/pep.c new file mode 100644 index 000000000000..c5dfecb207d2 --- /dev/null +++ b/net/phonet/pep.c @@ -0,0 +1,908 @@ +/* + * File: pep.c + * + * Phonet pipe protocol end point socket + * + * Copyright (C) 2008 Nokia Corporation. + * + * Author: Rémi Denis-Courmont <remi.denis-courmont@nokia.com> + * + * 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. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA + * 02110-1301 USA + */ + +#include <linux/kernel.h> +#include <linux/socket.h> +#include <net/sock.h> +#include <net/tcp_states.h> +#include <asm/ioctls.h> + +#include <linux/phonet.h> +#include <net/phonet/phonet.h> +#include <net/phonet/pep.h> + +/* sk_state values: + * TCP_CLOSE sock not in use yet + * TCP_CLOSE_WAIT disconnected pipe + * TCP_LISTEN listening pipe endpoint + * TCP_SYN_RECV connected pipe in disabled state + * TCP_ESTABLISHED connected pipe in enabled state + * + * pep_sock locking: + * - sk_state, ackq, hlist: sock lock needed + * - listener: read only + * - pipe_handle: read only + */ + +#define CREDITS_MAX 10 +#define CREDITS_THR 7 + +static const struct sockaddr_pn pipe_srv = { + .spn_family = AF_PHONET, + .spn_resource = 0xD9, /* pipe service */ +}; + +#define pep_sb_size(s) (((s) + 5) & ~3) /* 2-bytes head, 32-bits aligned */ + +/* Get the next TLV sub-block. */ +static unsigned char *pep_get_sb(struct sk_buff *skb, u8 *ptype, u8 *plen, + void *buf) +{ + void *data = NULL; + struct { + u8 sb_type; + u8 sb_len; + } *ph, h; + int buflen = *plen; + + ph = skb_header_pointer(skb, 0, 2, &h); + if (ph == NULL || ph->sb_len < 2 || !pskb_may_pull(skb, ph->sb_len)) + return NULL; + ph->sb_len -= 2; + *ptype = ph->sb_type; + *plen = ph->sb_len; + + if (buflen > ph->sb_len) + buflen = ph->sb_len; + data = skb_header_pointer(skb, 2, buflen, buf); + __skb_pull(skb, 2 + ph->sb_len); + return data; +} + +static int pep_reply(struct sock *sk, struct sk_buff *oskb, + u8 code, const void *data, int len, gfp_t priority) +{ + const struct pnpipehdr *oph = pnp_hdr(oskb); + struct pnpipehdr *ph; + struct sk_buff *skb; + + skb = alloc_skb(MAX_PNPIPE_HEADER + len, priority); + if (!skb) + return -ENOMEM; + skb_set_owner_w(skb, sk); + + skb_reserve(skb, MAX_PNPIPE_HEADER); + __skb_put(skb, len); + skb_copy_to_linear_data(skb, data, len); + __skb_push(skb, sizeof(*ph)); + skb_reset_transport_header(skb); + ph = pnp_hdr(skb); + ph->utid = oph->utid; + ph->message_id = oph->message_id + 1; /* REQ -> RESP */ + ph->pipe_handle = oph->pipe_handle; + ph->error_code = code; + + return pn_skb_send(sk, skb, &pipe_srv); +} + +#define PAD 0x00 +static int pep_accept_conn(struct sock *sk, struct sk_buff *skb) +{ + static const u8 data[20] = { + PAD, PAD, PAD, 2 /* sub-blocks */, + PN_PIPE_SB_REQUIRED_FC_TX, pep_sb_size(5), 3, PAD, + PN_MULTI_CREDIT_FLOW_CONTROL, + PN_ONE_CREDIT_FLOW_CONTROL, + PN_LEGACY_FLOW_CONTROL, + PAD, + PN_PIPE_SB_PREFERRED_FC_RX, pep_sb_size(5), 3, PAD, + PN_MULTI_CREDIT_FLOW_CONTROL, + PN_ONE_CREDIT_FLOW_CONTROL, + PN_LEGACY_FLOW_CONTROL, + PAD, + }; + + might_sleep(); + return pep_reply(sk, skb, PN_PIPE_NO_ERROR, data, sizeof(data), + GFP_KERNEL); +} + +static int pep_reject_conn(struct sock *sk, struct sk_buff *skb, u8 code) +{ + static const u8 data[4] = { PAD, PAD, PAD, 0 /* sub-blocks */ }; + WARN_ON(code == PN_PIPE_NO_ERROR); + return pep_reply(sk, skb, code, data, sizeof(data), GFP_ATOMIC); +} + +/* Control requests are not sent by the pipe service and have a specific + * message format. */ +static int pep_ctrlreq_error(struct sock *sk, struct sk_buff *oskb, u8 code) +{ + const struct pnpipehdr *oph = pnp_hdr(oskb); + struct sk_buff *skb; + struct pnpipehdr *ph; + struct sockaddr_pn dst; + + skb = alloc_skb(MAX_PNPIPE_HEADER + 4, GFP_ATOMIC); + if (!skb) + return -ENOMEM; + skb_set_owner_w(skb, sk); + + skb_reserve(skb, MAX_PHONET_HEADER); + ph = (struct pnpipehdr *)skb_put(skb, sizeof(*ph) + 4); + + ph->utid = oph->utid; + ph->message_id = PNS_PEP_CTRL_RESP; + ph->pipe_handle = oph->pipe_handle; + ph->data[0] = oph->data[1]; /* CTRL id */ + ph->data[1] = oph->data[0]; /* PEP type */ + ph->data[2] = code; /* error code, at an usual offset */ + ph->data[3] = PAD; + ph->data[4] = PAD; + + pn_skb_get_src_sockaddr(oskb, &dst); + return pn_skb_send(sk, skb, &dst); +} + +static int pipe_snd_status(struct sock *sk, u8 type, u8 status, gfp_t priority) +{ + struct pep_sock *pn = pep_sk(sk); + struct pnpipehdr *ph; + struct sk_buff *skb; + + skb = alloc_skb(MAX_PNPIPE_HEADER + 4, priority); + if (!skb) + return -ENOMEM; + skb_set_owner_w(skb, sk); + + skb_reserve(skb, MAX_PNPIPE_HEADER + 4); + __skb_push(skb, sizeof(*ph) + 4); + skb_reset_transport_header(skb); + ph = pnp_hdr(skb); + ph->utid = 0; + ph->message_id = PNS_PEP_STATUS_IND; + ph->pipe_handle = pn->pipe_handle; + ph->pep_type = PN_PEP_TYPE_COMMON; + ph->data[1] = type; + ph->data[2] = PAD; + ph->data[3] = PAD; + ph->data[4] = status; + + return pn_skb_send(sk, skb, &pipe_srv); +} + +/* Send our RX flow control information to the sender. + * Socket must be locked. */ +static void pipe_grant_credits(struct sock *sk) +{ + struct pep_sock *pn = pep_sk(sk); + + BUG_ON(sk->sk_state != TCP_ESTABLISHED); + + switch (pn->rx_fc) { + case PN_LEGACY_FLOW_CONTROL: /* TODO */ + break; + case PN_ONE_CREDIT_FLOW_CONTROL: + pipe_snd_status(sk, PN_PEP_IND_FLOW_CONTROL, + PEP_IND_READY, GFP_ATOMIC); + pn->rx_credits = 1; + break; + case PN_MULTI_CREDIT_FLOW_CONTROL: + if ((pn->rx_credits + CREDITS_THR) > CREDITS_MAX) + break; + if (pipe_snd_status(sk, PN_PEP_IND_ID_MCFC_GRANT_CREDITS, + CREDITS_MAX - pn->rx_credits, + GFP_ATOMIC) == 0) + pn->rx_credits = CREDITS_MAX; + break; + } +} + +static int pipe_rcv_status(struct sock *sk, struct sk_buff *skb) +{ + struct pep_sock *pn = pep_sk(sk); + struct pnpipehdr *hdr = pnp_hdr(skb); + + if (!pskb_may_pull(skb, sizeof(*hdr) + 4)) + return -EINVAL; + + if (hdr->data[0] != PN_PEP_TYPE_COMMON) { + LIMIT_NETDEBUG(KERN_DEBUG"Phonet unknown PEP type: %u\n", + (unsigned)hdr->data[0]); + return -EOPNOTSUPP; + } + + switch (hdr->data[1]) { + case PN_PEP_IND_FLOW_CONTROL: + switch (pn->tx_fc) { + case PN_LEGACY_FLOW_CONTROL: + switch (hdr->data[4]) { + case PEP_IND_BUSY: + pn->tx_credits = 0; + break; + case PEP_IND_READY: + pn->tx_credits = 1; + break; + } + break; + case PN_ONE_CREDIT_FLOW_CONTROL: + if (hdr->data[4] == PEP_IND_READY) + pn->tx_credits = 1; + break; + } + break; + + case PN_PEP_IND_ID_MCFC_GRANT_CREDITS: + if (pn->tx_fc != PN_MULTI_CREDIT_FLOW_CONTROL) + break; + if (pn->tx_credits + hdr->data[4] > 0xff) + pn->tx_credits = 0xff; + else + pn->tx_credits += hdr->data[4]; + break; + + default: + LIMIT_NETDEBUG(KERN_DEBUG"Phonet unknown PEP indication: %u\n", + (unsigned)hdr->data[1]); + return -EOPNOTSUPP; + } + if (pn->tx_credits) + sk->sk_write_space(sk); + return 0; +} + +static int pipe_rcv_created(struct sock *sk, struct sk_buff *skb) +{ + struct pep_sock *pn = pep_sk(sk); + struct pnpipehdr *hdr = pnp_hdr(skb); + u8 n_sb = hdr->data[0]; + + pn->rx_fc = pn->tx_fc = PN_LEGACY_FLOW_CONTROL; + __skb_pull(skb, sizeof(*hdr)); + while (n_sb > 0) { + u8 type, buf[2], len = sizeof(buf); + u8 *data = pep_get_sb(skb, &type, &len, buf); + + if (data == NULL) + return -EINVAL; + switch (type) { + case PN_PIPE_SB_NEGOTIATED_FC: + if (len < 2 || (data[0] | data[1]) > 3) + break; + pn->tx_fc = data[0] & 3; + pn->rx_fc = data[1] & 3; + break; + } + n_sb--; + } + return 0; +} + +/* Queue an skb to a connected sock. + * Socket lock must be held. */ +static int pipe_do_rcv(struct sock *sk, struct sk_buff *skb) +{ + struct pep_sock *pn = pep_sk(sk); + struct pnpipehdr *hdr = pnp_hdr(skb); + int err = 0; + + BUG_ON(sk->sk_state == TCP_CLOSE_WAIT); + + switch (hdr->message_id) { + case PNS_PEP_CONNECT_REQ: + pep_reject_conn(sk, skb, PN_PIPE_ERR_PEP_IN_USE); + break; + + case PNS_PEP_DISCONNECT_REQ: + pep_reply(sk, skb, PN_PIPE_NO_ERROR, NULL, 0, GFP_ATOMIC); + sk->sk_state = TCP_CLOSE_WAIT; + if (!sock_flag(sk, SOCK_DEAD)) + sk->sk_state_change(sk); + break; + + case PNS_PEP_ENABLE_REQ: + /* Wait for PNS_PIPE_(ENABLED|REDIRECTED)_IND */ + pep_reply(sk, skb, PN_PIPE_NO_ERROR, NULL, 0, GFP_ATOMIC); + break; + + case PNS_PEP_RESET_REQ: + switch (hdr->state_after_reset) { + case PN_PIPE_DISABLE: + pn->init_enable = 0; + break; + case PN_PIPE_ENABLE: + pn->init_enable = 1; + break; + default: /* not allowed to send an error here!? */ + err = -EINVAL; + goto out; + } + /* fall through */ + case PNS_PEP_DISABLE_REQ: + pn->tx_credits = 0; + pep_reply(sk, skb, PN_PIPE_NO_ERROR, NULL, 0, GFP_ATOMIC); + break; + + case PNS_PEP_CTRL_REQ: + /* TODO */ + pep_ctrlreq_error(sk, skb, PN_PIPE_NO_ERROR); + break; + + case PNS_PIPE_DATA: + __skb_pull(skb, 3); /* Pipe data header */ + if (!pn_flow_safe(pn->rx_fc)) { + err = sock_queue_rcv_skb(sk, skb); + if (!err) + return 0; + break; + } + + if (pn->rx_credits == 0) { + err = -ENOBUFS; + break; + } + pn->rx_credits--; + skb->dev = NULL; + skb_set_owner_r(skb, sk); + err = skb->len; + skb_queue_tail(&sk->sk_receive_queue, skb); + if (!sock_flag(sk, SOCK_DEAD)) + sk->sk_data_ready(sk, err); + return 0; + + case PNS_PEP_STATUS_IND: + pipe_rcv_status(sk, skb); + break; + + case PNS_PIPE_REDIRECTED_IND: + err = pipe_rcv_created(sk, skb); + break; + + case PNS_PIPE_CREATED_IND: + err = pipe_rcv_created(sk, skb); + if (err) + break; + /* fall through */ + case PNS_PIPE_RESET_IND: + if (!pn->init_enable) + break; + /* fall through */ + case PNS_PIPE_ENABLED_IND: + if (!pn_flow_safe(pn->tx_fc)) { + pn->tx_credits = 1; + sk->sk_write_space(sk); + } + if (sk->sk_state == TCP_ESTABLISHED) + break; /* Nothing to do */ + sk->sk_state = TCP_ESTABLISHED; + pipe_grant_credits(sk); + break; + + case PNS_PIPE_DISABLED_IND: + sk->sk_state = TCP_SYN_RECV; + pn->rx_credits = 0; + break; + + default: + LIMIT_NETDEBUG(KERN_DEBUG"Phonet unknown PEP message: %u\n", + hdr->message_id); + err = -EINVAL; + } +out: + kfree_skb(skb); + return err; +} + +/* Destroy connected sock. */ +static void pipe_destruct(struct sock *sk) +{ + skb_queue_purge(&sk->sk_receive_queue); +} + +static int pep_connreq_rcv(struct sock *sk, struct sk_buff *skb) +{ + struct sock *newsk; + struct pep_sock *newpn, *pn = pep_sk(sk); + struct pnpipehdr *hdr; + struct sockaddr_pn dst; + u16 peer_type; + u8 pipe_handle, enabled, n_sb; + + if (!pskb_pull(skb, sizeof(*hdr) + 4)) + return -EINVAL; + + hdr = pnp_hdr(skb); + pipe_handle = hdr->pipe_handle; + switch (hdr->state_after_connect) { + case PN_PIPE_DISABLE: + enabled = 0; + break; + case PN_PIPE_ENABLE: + enabled = 1; + break; + default: + pep_reject_conn(sk, skb, PN_PIPE_ERR_INVALID_PARAM); + return -EINVAL; + } + peer_type = hdr->other_pep_type << 8; + + if (unlikely(sk->sk_state != TCP_LISTEN) || sk_acceptq_is_full(sk)) { + pep_reject_conn(sk, skb, PN_PIPE_ERR_PEP_IN_USE); + return -ENOBUFS; + } + + /* Parse sub-blocks (options) */ + n_sb = hdr->data[4]; + while (n_sb > 0) { + u8 type, buf[1], len = sizeof(buf); + const u8 *data = pep_get_sb(skb, &type, &len, buf); + + if (data == NULL) + return -EINVAL; + switch (type) { + case PN_PIPE_SB_CONNECT_REQ_PEP_SUB_TYPE: + if (len < 1) + return -EINVAL; + peer_type = (peer_type & 0xff00) | data[0]; + break; + } + n_sb--; + } + + skb = skb_clone(skb, GFP_ATOMIC); + if (!skb) + return -ENOMEM; + + /* Create a new to-be-accepted sock */ + newsk = sk_alloc(sock_net(sk), PF_PHONET, GFP_ATOMIC, sk->sk_prot); + if (!newsk) { + kfree_skb(skb); + return -ENOMEM; + } + sock_init_data(NULL, newsk); + newsk->sk_state = TCP_SYN_RECV; + newsk->sk_backlog_rcv = pipe_do_rcv; + newsk->sk_protocol = sk->sk_protocol; + newsk->sk_destruct = pipe_destruct; + + newpn = pep_sk(newsk); + pn_skb_get_dst_sockaddr(skb, &dst); + newpn->pn_sk.sobject = pn_sockaddr_get_object(&dst); + newpn->pn_sk.resource = pn->pn_sk.resource; + newpn->pipe_handle = pipe_handle; + newpn->peer_type = peer_type; + newpn->rx_credits = newpn->tx_credits = 0; + newpn->rx_fc = newpn->tx_fc = PN_LEGACY_FLOW_CONTROL; + newpn->init_enable = enabled; + + BUG_ON(!skb_queue_empty(&newsk->sk_receive_queue)); + skb_queue_head(&newsk->sk_receive_queue, skb); + if (!sock_flag(sk, SOCK_DEAD)) + sk->sk_data_ready(sk, 0); + + sk_acceptq_added(sk); + sk_add_node(newsk, &pn->ackq); + return 0; +} + +/* Listening sock must be locked */ +static struct sock *pep_find_pipe(const struct hlist_head *hlist, + const struct sockaddr_pn *dst, + u8 pipe_handle) +{ + struct hlist_node *node; + struct sock *sknode; + u16 dobj = pn_sockaddr_get_object(dst); + + sk_for_each(sknode, node, hlist) { + struct pep_sock *pnnode = pep_sk(sknode); + + /* Ports match, but addresses might not: */ + if (pnnode->pn_sk.sobject != dobj) + continue; + if (pnnode->pipe_handle != pipe_handle) + continue; + if (sknode->sk_state == TCP_CLOSE_WAIT) + continue; + + sock_hold(sknode); + return sknode; + } + return NULL; +} + +/* + * Deliver an skb to a listening sock. + * Socket lock must be held. + * We then queue the skb to the right connected sock (if any). + */ +static int pep_do_rcv(struct sock *sk, struct sk_buff *skb) +{ + struct pep_sock *pn = pep_sk(sk); + struct sock *sknode; + struct pnpipehdr *hdr = pnp_hdr(skb); + struct sockaddr_pn dst; + int err = NET_RX_SUCCESS; + u8 pipe_handle; + + if (!pskb_may_pull(skb, sizeof(*hdr))) + goto drop; + + hdr = pnp_hdr(skb); + pipe_handle = hdr->pipe_handle; + if (pipe_handle == PN_PIPE_INVALID_HANDLE) + goto drop; + + pn_skb_get_dst_sockaddr(skb, &dst); + + /* Look for an existing pipe handle */ + sknode = pep_find_pipe(&pn->hlist, &dst, pipe_handle); + if (sknode) + return sk_receive_skb(sknode, skb, 1); + + /* Look for a pipe handle pending accept */ + sknode = pep_find_pipe(&pn->ackq, &dst, pipe_handle); + if (sknode) { + sock_put(sknode); + if (net_ratelimit()) + printk(KERN_WARNING"Phonet unconnected PEP ignored"); + err = NET_RX_DROP; + goto drop; + } + + switch (hdr->message_id) { + case PNS_PEP_CONNECT_REQ: + err = pep_connreq_rcv(sk, skb); + break; + + case PNS_PEP_DISCONNECT_REQ: + pep_reply(sk, skb, PN_PIPE_NO_ERROR, NULL, 0, GFP_ATOMIC); + break; + + case PNS_PEP_CTRL_REQ: + pep_ctrlreq_error(sk, skb, PN_PIPE_INVALID_HANDLE); + break; + + case PNS_PEP_RESET_REQ: + case PNS_PEP_ENABLE_REQ: + case PNS_PEP_DISABLE_REQ: + /* invalid handle is not even allowed here! */ + default: + err = NET_RX_DROP; + } +drop: + kfree_skb(skb); + return err; +} + +/* associated socket ceases to exist */ +static void pep_sock_close(struct sock *sk, long timeout) +{ + struct pep_sock *pn = pep_sk(sk); + + sk_common_release(sk); + + lock_sock(sk); + if (sk->sk_state == TCP_LISTEN) { + /* Destroy the listen queue */ + struct sock *sknode; + struct hlist_node *p, *n; + + sk_for_each_safe(sknode, p, n, &pn->ackq) + sk_del_node_init(sknode); + sk->sk_state = TCP_CLOSE; + } + release_sock(sk); +} + +static int pep_wait_connreq(struct sock *sk, int noblock) +{ + struct task_struct *tsk = current; + struct pep_sock *pn = pep_sk(sk); + long timeo = sock_rcvtimeo(sk, noblock); + + for (;;) { + DEFINE_WAIT(wait); + + if (sk->sk_state != TCP_LISTEN) + return -EINVAL; + if (!hlist_empty(&pn->ackq)) + break; + if (!timeo) + return -EWOULDBLOCK; + if (signal_pending(tsk)) + return sock_intr_errno(timeo); + + prepare_to_wait_exclusive(&sk->sk_socket->wait, &wait, + TASK_INTERRUPTIBLE); + release_sock(sk); + timeo = schedule_timeout(timeo); + lock_sock(sk); + finish_wait(&sk->sk_socket->wait, &wait); + } + + return 0; +} + +static struct sock *pep_sock_accept(struct sock *sk, int flags, int *errp) +{ + struct pep_sock *pn = pep_sk(sk); + struct sock *newsk = NULL; + struct sk_buff *oskb; + int err; + + lock_sock(sk); + err = pep_wait_connreq(sk, flags & O_NONBLOCK); + if (err) + goto out; + + newsk = __sk_head(&pn->ackq); + + oskb = skb_dequeue(&newsk->sk_receive_queue); + err = pep_accept_conn(newsk, oskb); + if (err) { + skb_queue_head(&newsk->sk_receive_queue, oskb); + newsk = NULL; + goto out; + } + + sock_hold(sk); + pep_sk(newsk)->listener = sk; + + sock_hold(newsk); + sk_del_node_init(newsk); + sk_acceptq_removed(sk); + sk_add_node(newsk, &pn->hlist); + __sock_put(newsk); + +out: + release_sock(sk); + *errp = err; + return newsk; +} + +static int pep_ioctl(struct sock *sk, int cmd, unsigned long arg) +{ + int answ; + + switch (cmd) { + case SIOCINQ: + if (sk->sk_state == TCP_LISTEN) + return -EINVAL; + + lock_sock(sk); + if (!skb_queue_empty(&sk->sk_receive_queue)) + answ = skb_peek(&sk->sk_receive_queue)->len; + else + answ = 0; + release_sock(sk); + return put_user(answ, (int __user *)arg); + } + + return -ENOIOCTLCMD; +} + +static int pep_init(struct sock *sk) +{ + struct pep_sock *pn = pep_sk(sk); + + INIT_HLIST_HEAD(&pn->ackq); + INIT_HLIST_HEAD(&pn->hlist); + pn->pipe_handle = PN_PIPE_INVALID_HANDLE; + return 0; +} + +static int pep_sendmsg(struct kiocb *iocb, struct sock *sk, + struct msghdr *msg, size_t len) +{ + struct pep_sock *pn = pep_sk(sk); + struct sk_buff *skb = NULL; + struct pnpipehdr *ph; + long timeo; + int flags = msg->msg_flags; + int err, done; + + if (msg->msg_flags & MSG_OOB || !(msg->msg_flags & MSG_EOR)) + return -EOPNOTSUPP; + + lock_sock(sk); + timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT); + if ((1 << sk->sk_state) & (TCPF_LISTEN|TCPF_CLOSE)) { + err = -ENOTCONN; + goto out; + } + if (sk->sk_state != TCP_ESTABLISHED) { + /* Wait until the pipe gets to enabled state */ +disabled: + err = sk_stream_wait_connect(sk, &timeo); + if (err) + goto out; + + if (sk->sk_state == TCP_CLOSE_WAIT) { + err = -ECONNRESET; + goto out; + } + } + BUG_ON(sk->sk_state != TCP_ESTABLISHED); + + /* Wait until flow control allows TX */ + done = pn->tx_credits > 0; + while (!done) { + DEFINE_WAIT(wait); + + if (!timeo) { + err = -EAGAIN; + goto out; + } + if (signal_pending(current)) { + err = sock_intr_errno(timeo); + goto out; + } + + prepare_to_wait(&sk->sk_socket->wait, &wait, + TASK_INTERRUPTIBLE); + done = sk_wait_event(sk, &timeo, pn->tx_credits > 0); + finish_wait(&sk->sk_socket->wait, &wait); + + if (sk->sk_state != TCP_ESTABLISHED) + goto disabled; + } + + if (!skb) { + skb = sock_alloc_send_skb(sk, MAX_PNPIPE_HEADER + len, + flags & MSG_DONTWAIT, &err); + if (skb == NULL) + goto out; + skb_reserve(skb, MAX_PHONET_HEADER + 3); + + if (sk->sk_state != TCP_ESTABLISHED || !pn->tx_credits) + goto disabled; /* sock_alloc_send_skb might sleep */ + } + + err = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len); + if (err < 0) + goto out; + + __skb_push(skb, 3); + skb_reset_transport_header(skb); + ph = pnp_hdr(skb); + ph->utid = 0; + ph->message_id = PNS_PIPE_DATA; + ph->pipe_handle = pn->pipe_handle; + if (pn_flow_safe(pn->tx_fc)) /* credit-based flow control */ + pn->tx_credits--; + + err = pn_skb_send(sk, skb, &pipe_srv); + if (err >= 0) + err = len; /* success! */ + skb = NULL; +out: + release_sock(sk); + kfree_skb(skb); + return err; +} + +static int pep_recvmsg(struct kiocb *iocb, struct sock *sk, + struct msghdr *msg, size_t len, int noblock, + int flags, int *addr_len) +{ + struct sk_buff *skb; + int err; + + if (unlikely(flags & MSG_OOB)) + return -EOPNOTSUPP; + if (unlikely(1 << sk->sk_state & (TCPF_LISTEN | TCPF_CLOSE))) + return -ENOTCONN; + + skb = skb_recv_datagram(sk, flags, noblock, &err); + lock_sock(sk); + if (skb == NULL) { + if (err == -ENOTCONN && sk->sk_state == TCP_CLOSE_WAIT) + err = -ECONNRESET; + release_sock(sk); + return err; + } + + if (sk->sk_state == TCP_ESTABLISHED) + pipe_grant_credits(sk); + release_sock(sk); + + msg->msg_flags |= MSG_EOR; + + if (skb->len > len) + msg->msg_flags |= MSG_TRUNC; + else + len = skb->len; + + err = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, len); + if (!err) + err = (flags & MSG_TRUNC) ? skb->len : len; + + skb_free_datagram(sk, skb); + return err; +} + +static void pep_sock_unhash(struct sock *sk) +{ + struct pep_sock *pn = pep_sk(sk); + struct sock *skparent = NULL; + + lock_sock(sk); + if ((1 << sk->sk_state) & ~(TCPF_CLOSE|TCPF_LISTEN)) { + skparent = pn->listener; + sk_del_node_init(sk); + release_sock(sk); + + sk = skparent; + pn = pep_sk(skparent); + lock_sock(sk); + } + /* Unhash a listening sock only when it is closed + * and all of its active connected pipes are closed. */ + if (hlist_empty(&pn->hlist)) + pn_sock_unhash(&pn->pn_sk.sk); + release_sock(sk); + + if (skparent) + sock_put(skparent); +} + +static struct proto pep_proto = { + .close = pep_sock_close, + .accept = pep_sock_accept, + .ioctl = pep_ioctl, + .init = pep_init, + .sendmsg = pep_sendmsg, + .recvmsg = pep_recvmsg, + .backlog_rcv = pep_do_rcv, + .hash = pn_sock_hash, + .unhash = pep_sock_unhash, + .get_port = pn_sock_get_port, + .obj_size = sizeof(struct pep_sock), + .owner = THIS_MODULE, + .name = "PNPIPE", +}; + +static struct phonet_protocol pep_pn_proto = { + .ops = &phonet_stream_ops, + .prot = &pep_proto, + .sock_type = SOCK_SEQPACKET, +}; + +static int __init pep_register(void) +{ + return phonet_proto_register(PN_PROTO_PIPE, &pep_pn_proto); +} + +static void __exit pep_unregister(void) +{ + phonet_proto_unregister(PN_PROTO_PIPE, &pep_pn_proto); +} + +module_init(pep_register); +module_exit(pep_unregister); +MODULE_AUTHOR("Remi Denis-Courmont, Nokia"); +MODULE_DESCRIPTION("Phonet pipe protocol"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS_NET_PF_PROTO(PF_PHONET, PN_PROTO_PIPE); |