/* * 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/slab.h> #include <linux/socket.h> #include <net/sock.h> #include <net/tcp_states.h> #include <asm/ioctls.h> #include <linux/phonet.h> #include <linux/module.h> #include <net/phonet/phonet.h> #include <net/phonet/pep.h> #include <net/phonet/gprs.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, hlist: sock lock needed * - listener: read only * - pipe_handle: read only */ #define CREDITS_MAX 10 #define CREDITS_THR 7 #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 struct sk_buff *pep_alloc_skb(struct sock *sk, const void *payload, int len, gfp_t priority) { struct sk_buff *skb = alloc_skb(MAX_PNPIPE_HEADER + len, priority); if (!skb) return NULL; skb_set_owner_w(skb, sk); skb_reserve(skb, MAX_PNPIPE_HEADER); __skb_put(skb, len); skb_copy_to_linear_data(skb, payload, len); __skb_push(skb, sizeof(struct pnpipehdr)); skb_reset_transport_header(skb); return skb; } 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; struct sockaddr_pn peer; skb = pep_alloc_skb(sk, data, len, priority); if (!skb) return -ENOMEM; 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; pn_skb_get_src_sockaddr(oskb, &peer); return pn_skb_send(sk, skb, &peer); } static int pep_indicate(struct sock *sk, u8 id, u8 code, const void *data, int len, gfp_t priority) { struct pep_sock *pn = pep_sk(sk); struct pnpipehdr *ph; struct sk_buff *skb; skb = pep_alloc_skb(sk, data, len, priority); if (!skb) return -ENOMEM; ph = pnp_hdr(skb); ph->utid = 0; ph->message_id = id; ph->pipe_handle = pn->pipe_handle; ph->data[0] = code; return pn_skb_send(sk, skb, NULL); } #define PAD 0x00 static int pipe_handler_request(struct sock *sk, u8 id, u8 code, const void *data, int len) { struct pep_sock *pn = pep_sk(sk); struct pnpipehdr *ph; struct sk_buff *skb; skb = pep_alloc_skb(sk, data, len, GFP_KERNEL); if (!skb) return -ENOMEM; ph = pnp_hdr(skb); ph->utid = id; /* whatever */ ph->message_id = id; ph->pipe_handle = pn->pipe_handle; ph->data[0] = code; return pn_skb_send(sk, skb, NULL); } static int pipe_handler_send_created_ind(struct sock *sk) { struct pep_sock *pn = pep_sk(sk); u8 data[4] = { PN_PIPE_SB_NEGOTIATED_FC, pep_sb_size(2), pn->tx_fc, pn->rx_fc, }; return pep_indicate(sk, PNS_PIPE_CREATED_IND, 1 /* sub-blocks */, data, 4, GFP_ATOMIC); } 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, gfp_t priority) { 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), priority); } /* 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, gfp_t priority) { const struct pnpipehdr *oph = pnp_hdr(oskb); struct sk_buff *skb; struct pnpipehdr *ph; struct sockaddr_pn dst; u8 data[4] = { oph->data[0], /* PEP type */ code, /* error code, at an unusual offset */ PAD, PAD, }; skb = pep_alloc_skb(sk, data, 4, priority); if (!skb) return -ENOMEM; ph = pnp_hdr(skb); 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 */ 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) { u8 data[4] = { type, PAD, PAD, status }; return pep_indicate(sk, PNS_PEP_STATUS_IND, PN_PEP_TYPE_COMMON, data, 4, priority); } /* Send our RX flow control information to the sender. * Socket must be locked. */ static void pipe_grant_credits(struct sock *sk, gfp_t priority) { 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: if (pipe_snd_status(sk, PN_PEP_IND_FLOW_CONTROL, PEP_IND_READY, priority) == 0) 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, priority) == 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; int wake = 0; if (!pskb_may_pull(skb, sizeof(*hdr) + 4)) return -EINVAL; hdr = pnp_hdr(skb); 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: atomic_set(&pn->tx_credits, 0); break; case PEP_IND_READY: atomic_set(&pn->tx_credits, wake = 1); break; } break; case PN_ONE_CREDIT_FLOW_CONTROL: if (hdr->data[4] == PEP_IND_READY) atomic_set(&pn->tx_credits, wake = 1); break; } break; case PN_PEP_IND_ID_MCFC_GRANT_CREDITS: if (pn->tx_fc != PN_MULTI_CREDIT_FLOW_CONTROL) break; atomic_add(wake = hdr->data[4], &pn->tx_credits); break; default: LIMIT_NETDEBUG(KERN_DEBUG"Phonet unknown PEP indication: %u\n", (unsigned)hdr->data[1]); return -EOPNOTSUPP; } if (wake) 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); struct sk_buff_head *queue; 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, GFP_ATOMIC); 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: atomic_set(&pn->tx_credits, 0); pep_reply(sk, skb, PN_PIPE_NO_ERROR, NULL, 0, GFP_ATOMIC); break; case PNS_PEP_CTRL_REQ: if (skb_queue_len(&pn->ctrlreq_queue) >= PNPIPE_CTRLREQ_MAX) { atomic_inc(&sk->sk_drops); break; } __skb_pull(skb, 4); queue = &pn->ctrlreq_queue; goto queue; case PNS_PIPE_ALIGNED_DATA: __skb_pull(skb, 1); /* fall through */ 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 NET_RX_SUCCESS; err = -ENOBUFS; break; } if (pn->rx_credits == 0) { atomic_inc(&sk->sk_drops); err = -ENOBUFS; break; } pn->rx_credits--; queue = &sk->sk_receive_queue; goto queue; 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)) { atomic_set(&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, GFP_ATOMIC); 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 == -ENOBUFS) ? NET_RX_DROP : NET_RX_SUCCESS; queue: skb->dev = NULL; skb_set_owner_r(skb, sk); err = skb->len; skb_queue_tail(queue, skb); if (!sock_flag(sk, SOCK_DEAD)) sk->sk_data_ready(sk, err); return NET_RX_SUCCESS; } /* Destroy connected sock. */ static void pipe_destruct(struct sock *sk) { struct pep_sock *pn = pep_sk(sk); skb_queue_purge(&sk->sk_receive_queue); skb_queue_purge(&pn->ctrlreq_queue); } static u8 pipe_negotiate_fc(const u8 *fcs, unsigned n) { unsigned i; u8 final_fc = PN_NO_FLOW_CONTROL; for (i = 0; i < n; i++) { u8 fc = fcs[i]; if (fc > final_fc && fc < PN_MAX_FLOW_CONTROL) final_fc = fc; } return final_fc; } static int pep_connresp_rcv(struct sock *sk, struct sk_buff *skb) { struct pep_sock *pn = pep_sk(sk); struct pnpipehdr *hdr; u8 n_sb; if (!pskb_pull(skb, sizeof(*hdr) + 4)) return -EINVAL; hdr = pnp_hdr(skb); if (hdr->error_code != PN_PIPE_NO_ERROR) return -ECONNREFUSED; /* Parse sub-blocks */ n_sb = hdr->data[4]; while (n_sb > 0) { u8 type, buf[6], len = sizeof(buf); const u8 *data = pep_get_sb(skb, &type, &len, buf); if (data == NULL) return -EINVAL; switch (type) { case PN_PIPE_SB_REQUIRED_FC_TX: if (len < 2 || len < data[0]) break; pn->tx_fc = pipe_negotiate_fc(data + 2, len - 2); break; case PN_PIPE_SB_PREFERRED_FC_RX: if (len < 2 || len < data[0]) break; pn->rx_fc = pipe_negotiate_fc(data + 2, len - 2); break; } n_sb--; } return pipe_handler_send_created_ind(sk); } static int pep_enableresp_rcv(struct sock *sk, struct sk_buff *skb) { struct pnpipehdr *hdr = pnp_hdr(skb); if (hdr->error_code != PN_PIPE_NO_ERROR) return -ECONNREFUSED; return pep_indicate(sk, PNS_PIPE_ENABLED_IND, 0 /* sub-blocks */, NULL, 0, GFP_ATOMIC); } static void pipe_start_flow_control(struct sock *sk) { struct pep_sock *pn = pep_sk(sk); if (!pn_flow_safe(pn->tx_fc)) { atomic_set(&pn->tx_credits, 1); sk->sk_write_space(sk); } pipe_grant_credits(sk, GFP_ATOMIC); } /* Queue an skb to an actively connected sock. * Socket lock must be held. */ static int pipe_handler_do_rcv(struct sock *sk, struct sk_buff *skb) { struct pep_sock *pn = pep_sk(sk); struct pnpipehdr *hdr = pnp_hdr(skb); int err = NET_RX_SUCCESS; switch (hdr->message_id) { case PNS_PIPE_ALIGNED_DATA: __skb_pull(skb, 1); /* fall through */ 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 NET_RX_SUCCESS; err = NET_RX_DROP; break; } if (pn->rx_credits == 0) { atomic_inc(&sk->sk_drops); err = NET_RX_DROP; 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 NET_RX_SUCCESS; case PNS_PEP_CONNECT_RESP: if (sk->sk_state != TCP_SYN_SENT) break; if (!sock_flag(sk, SOCK_DEAD)) sk->sk_state_change(sk); if (pep_connresp_rcv(sk, skb)) { sk->sk_state = TCP_CLOSE_WAIT; break; } if (pn->init_enable == PN_PIPE_DISABLE) sk->sk_state = TCP_SYN_RECV; else { sk->sk_state = TCP_ESTABLISHED; pipe_start_flow_control(sk); } break; case PNS_PEP_ENABLE_RESP: if (sk->sk_state != TCP_SYN_SENT) break; if (pep_enableresp_rcv(sk, skb)) { sk->sk_state = TCP_CLOSE_WAIT; break; } sk->sk_state = TCP_ESTABLISHED; pipe_start_flow_control(sk); break; case PNS_PEP_DISCONNECT_RESP: /* sock should already be dead, nothing to do */ break; case PNS_PEP_STATUS_IND: pipe_rcv_status(sk, skb); break; } kfree_skb(skb); return err; } /* 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; struct sockaddr_pn dst; 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); switch (hdr->message_id) { case PNS_PEP_CONNECT_REQ: if (sk->sk_state != TCP_LISTEN || sk_acceptq_is_full(sk)) { pep_reject_conn(sk, skb, PN_PIPE_ERR_PEP_IN_USE, GFP_ATOMIC); break; } skb_queue_head(&sk->sk_receive_queue, skb); sk_acceptq_added(sk); if (!sock_flag(sk, SOCK_DEAD)) sk->sk_data_ready(sk, 0); return NET_RX_SUCCESS; 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, GFP_ATOMIC); break; case PNS_PEP_RESET_REQ: case PNS_PEP_ENABLE_REQ: case PNS_PEP_DISABLE_REQ: /* invalid handle is not even allowed here! */ break; default: if ((1 << sk->sk_state) & ~(TCPF_CLOSE|TCPF_LISTEN|TCPF_CLOSE_WAIT)) /* actively connected socket */ return pipe_handler_do_rcv(sk, skb); } drop: kfree_skb(skb); return NET_RX_SUCCESS; } static int pipe_do_remove(struct sock *sk) { struct pep_sock *pn = pep_sk(sk); struct pnpipehdr *ph; struct sk_buff *skb; skb = pep_alloc_skb(sk, NULL, 0, GFP_KERNEL); if (!skb) return -ENOMEM; ph = pnp_hdr(skb); ph->utid = 0; ph->message_id = PNS_PIPE_REMOVE_REQ; ph->pipe_handle = pn->pipe_handle; ph->data[0] = PAD; return pn_skb_send(sk, skb, NULL); } /* associated socket ceases to exist */ static void pep_sock_close(struct sock *sk, long timeout) { struct pep_sock *pn = pep_sk(sk); int ifindex = 0; sock_hold(sk); /* keep a reference after sk_common_release() */ sk_common_release(sk); lock_sock(sk); if ((1 << sk->sk_state) & (TCPF_SYN_RECV|TCPF_ESTABLISHED)) { if (sk->sk_backlog_rcv == pipe_do_rcv) /* Forcefully remove dangling Phonet pipe */ pipe_do_remove(sk); else pipe_handler_request(sk, PNS_PEP_DISCONNECT_REQ, PAD, NULL, 0); } sk->sk_state = TCP_CLOSE; ifindex = pn->ifindex; pn->ifindex = 0; release_sock(sk); if (ifindex) gprs_detach(sk); sock_put(sk); } static struct sock *pep_sock_accept(struct sock *sk, int flags, int *errp) { struct pep_sock *pn = pep_sk(sk), *newpn; struct sock *newsk = NULL; struct sk_buff *skb; struct pnpipehdr *hdr; struct sockaddr_pn dst, src; int err; u16 peer_type; u8 pipe_handle, enabled, n_sb; u8 aligned = 0; skb = skb_recv_datagram(sk, 0, flags & O_NONBLOCK, errp); if (!skb) return NULL; lock_sock(sk); if (sk->sk_state != TCP_LISTEN) { err = -EINVAL; goto drop; } sk_acceptq_removed(sk); err = -EPROTO; if (!pskb_may_pull(skb, sizeof(*hdr) + 4)) goto drop; 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, GFP_KERNEL); goto drop; } peer_type = hdr->other_pep_type << 8; /* 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) goto drop; switch (type) { case PN_PIPE_SB_CONNECT_REQ_PEP_SUB_TYPE: if (len < 1) goto drop; peer_type = (peer_type & 0xff00) | data[0]; break; case PN_PIPE_SB_ALIGNED_DATA: aligned = data[0] != 0; break; } n_sb--; } /* Check for duplicate pipe handle */ newsk = pep_find_pipe(&pn->hlist, &dst, pipe_handle); if (unlikely(newsk)) { __sock_put(newsk); newsk = NULL; pep_reject_conn(sk, skb, PN_PIPE_ERR_PEP_IN_USE, GFP_KERNEL); goto drop; } /* Create a new to-be-accepted sock */ newsk = sk_alloc(sock_net(sk), PF_PHONET, GFP_KERNEL, sk->sk_prot); if (!newsk) { pep_reject_conn(sk, skb, PN_PIPE_ERR_OVERLOAD, GFP_KERNEL); err = -ENOBUFS; goto drop; } 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); pn_skb_get_src_sockaddr(skb, &src); newpn->pn_sk.sobject = pn_sockaddr_get_object(&dst); newpn->pn_sk.dobject = pn_sockaddr_get_object(&src); newpn->pn_sk.resource = pn_sockaddr_get_resource(&dst); sock_hold(sk); newpn->listener = sk; skb_queue_head_init(&newpn->ctrlreq_queue); newpn->pipe_handle = pipe_handle; atomic_set(&newpn->tx_credits, 0); newpn->ifindex = 0; newpn->peer_type = peer_type; newpn->rx_credits = 0; newpn->rx_fc = newpn->tx_fc = PN_LEGACY_FLOW_CONTROL; newpn->init_enable = enabled; newpn->aligned = aligned; err = pep_accept_conn(newsk, skb); if (err) { sock_put(newsk); newsk = NULL; goto drop; } sk_add_node(newsk, &pn->hlist); drop: release_sock(sk); kfree_skb(skb); *errp = err; return newsk; } static int pep_sock_connect(struct sock *sk, struct sockaddr *addr, int len) { struct pep_sock *pn = pep_sk(sk); int err; u8 data[4] = { 0 /* sub-blocks */, PAD, PAD, PAD }; if (pn->pipe_handle == PN_PIPE_INVALID_HANDLE) pn->pipe_handle = 1; /* anything but INVALID_HANDLE */ err = pipe_handler_request(sk, PNS_PEP_CONNECT_REQ, pn->init_enable, data, 4); if (err) { pn->pipe_handle = PN_PIPE_INVALID_HANDLE; return err; } sk->sk_state = TCP_SYN_SENT; return 0; } static int pep_sock_enable(struct sock *sk, struct sockaddr *addr, int len) { int err; err = pipe_handler_request(sk, PNS_PEP_ENABLE_REQ, PAD, NULL, 0); if (err) return err; sk->sk_state = TCP_SYN_SENT; return 0; } static int pep_ioctl(struct sock *sk, int cmd, unsigned long arg) { struct pep_sock *pn = pep_sk(sk); int answ; int ret = -ENOIOCTLCMD; switch (cmd) { case SIOCINQ: if (sk->sk_state == TCP_LISTEN) { ret = -EINVAL; break; } lock_sock(sk); if (sock_flag(sk, SOCK_URGINLINE) && !skb_queue_empty(&pn->ctrlreq_queue)) answ = skb_peek(&pn->ctrlreq_queue)->len; else if (!skb_queue_empty(&sk->sk_receive_queue)) answ = skb_peek(&sk->sk_receive_queue)->len; else answ = 0; release_sock(sk); ret = put_user(answ, (int __user *)arg); break; case SIOCPNENABLEPIPE: lock_sock(sk); if (sk->sk_state == TCP_SYN_SENT) ret = -EBUSY; else if (sk->sk_state == TCP_ESTABLISHED) ret = -EISCONN; else ret = pep_sock_enable(sk, NULL, 0); release_sock(sk); break; } return ret; } static int pep_init(struct sock *sk) { struct pep_sock *pn = pep_sk(sk); sk->sk_destruct = pipe_destruct; INIT_HLIST_HEAD(&pn->hlist); pn->listener = NULL; skb_queue_head_init(&pn->ctrlreq_queue); atomic_set(&pn->tx_credits, 0); pn->ifindex = 0; pn->peer_type = 0; pn->pipe_handle = PN_PIPE_INVALID_HANDLE; pn->rx_credits = 0; pn->rx_fc = pn->tx_fc = PN_LEGACY_FLOW_CONTROL; pn->init_enable = 1; pn->aligned = 0; return 0; } static int pep_setsockopt(struct sock *sk, int level, int optname, char __user *optval, unsigned int optlen) { struct pep_sock *pn = pep_sk(sk); int val = 0, err = 0; if (level != SOL_PNPIPE) return -ENOPROTOOPT; if (optlen >= sizeof(int)) { if (get_user(val, (int __user *) optval)) return -EFAULT; } lock_sock(sk); switch (optname) { case PNPIPE_ENCAP: if (val && val != PNPIPE_ENCAP_IP) { err = -EINVAL; break; } if (!pn->ifindex == !val) break; /* Nothing to do! */ if (!capable(CAP_NET_ADMIN)) { err = -EPERM; break; } if (val) { release_sock(sk); err = gprs_attach(sk); if (err > 0) { pn->ifindex = err; err = 0; } } else { pn->ifindex = 0; release_sock(sk); gprs_detach(sk); err = 0; } goto out_norel; case PNPIPE_HANDLE: if ((sk->sk_state == TCP_CLOSE) && (val >= 0) && (val < PN_PIPE_INVALID_HANDLE)) pn->pipe_handle = val; else err = -EINVAL; break; case PNPIPE_INITSTATE: pn->init_enable = !!val; break; default: err = -ENOPROTOOPT; } release_sock(sk); out_norel: return err; } static int pep_getsockopt(struct sock *sk, int level, int optname, char __user *optval, int __user *optlen) { struct pep_sock *pn = pep_sk(sk); int len, val; if (level != SOL_PNPIPE) return -ENOPROTOOPT; if (get_user(len, optlen)) return -EFAULT; switch (optname) { case PNPIPE_ENCAP: val = pn->ifindex ? PNPIPE_ENCAP_IP : PNPIPE_ENCAP_NONE; break; case PNPIPE_IFINDEX: val = pn->ifindex; break; case PNPIPE_HANDLE: val = pn->pipe_handle; if (val == PN_PIPE_INVALID_HANDLE) return -EINVAL; break; case PNPIPE_INITSTATE: val = pn->init_enable; break; default: return -ENOPROTOOPT; } len = min_t(unsigned int, sizeof(int), len); if (put_user(len, optlen)) return -EFAULT; if (put_user(val, (int __user *) optval)) return -EFAULT; return 0; } static int pipe_skb_send(struct sock *sk, struct sk_buff *skb) { struct pep_sock *pn = pep_sk(sk); struct pnpipehdr *ph; int err; if (pn_flow_safe(pn->tx_fc) && !atomic_add_unless(&pn->tx_credits, -1, 0)) { kfree_skb(skb); return -ENOBUFS; } skb_push(skb, 3 + pn->aligned); skb_reset_transport_header(skb); ph = pnp_hdr(skb); ph->utid = 0; if (pn->aligned) { ph->message_id = PNS_PIPE_ALIGNED_DATA; ph->data[0] = 0; /* padding */ } else ph->message_id = PNS_PIPE_DATA; ph->pipe_handle = pn->pipe_handle; err = pn_skb_send(sk, skb, NULL); if (err && pn_flow_safe(pn->tx_fc)) atomic_inc(&pn->tx_credits); return err; } 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; long timeo; int flags = msg->msg_flags; int err, done; if (len > USHRT_MAX) return -EMSGSIZE; if ((msg->msg_flags & ~(MSG_DONTWAIT|MSG_EOR|MSG_NOSIGNAL| MSG_CMSG_COMPAT)) || !(msg->msg_flags & MSG_EOR)) return -EOPNOTSUPP; skb = sock_alloc_send_skb(sk, MAX_PNPIPE_HEADER + len, flags & MSG_DONTWAIT, &err); if (!skb) return err; skb_reserve(skb, MAX_PHONET_HEADER + 3 + pn->aligned); err = memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len); if (err < 0) goto outfree; 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 = atomic_read(&pn->tx_credits); 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_sleep(sk), &wait, TASK_INTERRUPTIBLE); done = sk_wait_event(sk, &timeo, atomic_read(&pn->tx_credits)); finish_wait(sk_sleep(sk), &wait); if (sk->sk_state != TCP_ESTABLISHED) goto disabled; } err = pipe_skb_send(sk, skb); if (err >= 0) err = len; /* success! */ skb = NULL; out: release_sock(sk); outfree: kfree_skb(skb); return err; } int pep_writeable(struct sock *sk) { struct pep_sock *pn = pep_sk(sk); return atomic_read(&pn->tx_credits); } int pep_write(struct sock *sk, struct sk_buff *skb) { struct sk_buff *rskb, *fs; int flen = 0; if (pep_sk(sk)->aligned) return pipe_skb_send(sk, skb); rskb = alloc_skb(MAX_PNPIPE_HEADER, GFP_ATOMIC); if (!rskb) { kfree_skb(skb); return -ENOMEM; } skb_shinfo(rskb)->frag_list = skb; rskb->len += skb->len; rskb->data_len += rskb->len; rskb->truesize += rskb->len; /* Avoid nested fragments */ skb_walk_frags(skb, fs) flen += fs->len; skb->next = skb_shinfo(skb)->frag_list; skb_frag_list_init(skb); skb->len -= flen; skb->data_len -= flen; skb->truesize -= flen; skb_reserve(rskb, MAX_PHONET_HEADER + 3); return pipe_skb_send(sk, rskb); } struct sk_buff *pep_read(struct sock *sk) { struct sk_buff *skb = skb_dequeue(&sk->sk_receive_queue); if (sk->sk_state == TCP_ESTABLISHED) pipe_grant_credits(sk, GFP_ATOMIC); return skb; } 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 (flags & ~(MSG_OOB|MSG_PEEK|MSG_TRUNC|MSG_DONTWAIT|MSG_WAITALL| MSG_NOSIGNAL|MSG_CMSG_COMPAT)) return -EOPNOTSUPP; if (unlikely(1 << sk->sk_state & (TCPF_LISTEN | TCPF_CLOSE))) return -ENOTCONN; if ((flags & MSG_OOB) || sock_flag(sk, SOCK_URGINLINE)) { /* Dequeue and acknowledge control request */ struct pep_sock *pn = pep_sk(sk); if (flags & MSG_PEEK) return -EOPNOTSUPP; skb = skb_dequeue(&pn->ctrlreq_queue); if (skb) { pep_ctrlreq_error(sk, skb, PN_PIPE_NO_ERROR, GFP_KERNEL); msg->msg_flags |= MSG_OOB; goto copy; } if (flags & MSG_OOB) return -EINVAL; } 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, GFP_KERNEL); release_sock(sk); copy: 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 (pn->listener != NULL) { skparent = pn->listener; pn->listener = NULL; release_sock(sk); pn = pep_sk(skparent); lock_sock(skparent); sk_del_node_init(sk); sk = skparent; } /* 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, .connect = pep_sock_connect, .ioctl = pep_ioctl, .init = pep_init, .setsockopt = pep_setsockopt, .getsockopt = pep_getsockopt, .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);