--- /dev/null
+/*
+ * File: pep.c
+ *
+ * Phonet pipe protocol end point socket
+ *
+ * Copyright (C) 2008 Nokia Corporation.
+ *
+ * Author: Rémi Denis-Courmont
+ *
+ * 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) {
+ net_dbg_ratelimited("Phonet unknown PEP type: %u\n",
+ (unsigned int)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:
+ net_dbg_ratelimited("Phonet unknown PEP indication: %u\n",
+ (unsigned int)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:
+ net_dbg_ratelimited("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);
+ skb_queue_tail(queue, skb);
+ if (!sock_flag(sk, SOCK_DEAD))
+ sk->sk_data_ready(sk);
+ 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 int n)
+{
+ unsigned int 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);
+ skb_queue_tail(&sk->sk_receive_queue, skb);
+ if (!sock_flag(sk, SOCK_DEAD))
+ sk->sk_data_ready(sk);
+ 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 sock *sknode;
+ u16 dobj = pn_sockaddr_get_object(dst);
+
+ sk_for_each(sknode, 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);
+ 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 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_from_msg(skb_put(skb, len), msg, 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 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_msg(skb, 0, msg, 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);
Code Review / kvmfornfv.git / blobdiff