Remi Denis-Courmont | 107d0d9 | 2008-09-22 20:05:57 -0700 | [diff] [blame^] | 1 | /* |
| 2 | * File: datagram.c |
| 3 | * |
| 4 | * Datagram (ISI) Phonet sockets |
| 5 | * |
| 6 | * Copyright (C) 2008 Nokia Corporation. |
| 7 | * |
| 8 | * Contact: Remi Denis-Courmont <remi.denis-courmont@nokia.com> |
| 9 | * Original author: Sakari Ailus <sakari.ailus@nokia.com> |
| 10 | * |
| 11 | * This program is free software; you can redistribute it and/or |
| 12 | * modify it under the terms of the GNU General Public License |
| 13 | * version 2 as published by the Free Software Foundation. |
| 14 | * |
| 15 | * This program is distributed in the hope that it will be useful, but |
| 16 | * WITHOUT ANY WARRANTY; without even the implied warranty of |
| 17 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 18 | * General Public License for more details. |
| 19 | * |
| 20 | * You should have received a copy of the GNU General Public License |
| 21 | * along with this program; if not, write to the Free Software |
| 22 | * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA |
| 23 | * 02110-1301 USA |
| 24 | */ |
| 25 | |
| 26 | #include <linux/kernel.h> |
| 27 | #include <linux/socket.h> |
| 28 | #include <asm/ioctls.h> |
| 29 | #include <net/sock.h> |
| 30 | |
| 31 | #include <linux/phonet.h> |
| 32 | #include <net/phonet/phonet.h> |
| 33 | |
| 34 | static int pn_backlog_rcv(struct sock *sk, struct sk_buff *skb); |
| 35 | |
| 36 | /* associated socket ceases to exist */ |
| 37 | static void pn_sock_close(struct sock *sk, long timeout) |
| 38 | { |
| 39 | sk_common_release(sk); |
| 40 | } |
| 41 | |
| 42 | static int pn_ioctl(struct sock *sk, int cmd, unsigned long arg) |
| 43 | { |
| 44 | struct sk_buff *skb; |
| 45 | int answ; |
| 46 | |
| 47 | switch (cmd) { |
| 48 | case SIOCINQ: |
| 49 | lock_sock(sk); |
| 50 | skb = skb_peek(&sk->sk_receive_queue); |
| 51 | answ = skb ? skb->len : 0; |
| 52 | release_sock(sk); |
| 53 | return put_user(answ, (int __user *)arg); |
| 54 | } |
| 55 | |
| 56 | return -ENOIOCTLCMD; |
| 57 | } |
| 58 | |
| 59 | /* Destroy socket. All references are gone. */ |
| 60 | static void pn_destruct(struct sock *sk) |
| 61 | { |
| 62 | skb_queue_purge(&sk->sk_receive_queue); |
| 63 | } |
| 64 | |
| 65 | static int pn_init(struct sock *sk) |
| 66 | { |
| 67 | sk->sk_destruct = pn_destruct; |
| 68 | return 0; |
| 69 | } |
| 70 | |
| 71 | static int pn_sendmsg(struct kiocb *iocb, struct sock *sk, |
| 72 | struct msghdr *msg, size_t len) |
| 73 | { |
| 74 | struct sockaddr_pn *target; |
| 75 | struct sk_buff *skb; |
| 76 | int err; |
| 77 | |
| 78 | if (msg->msg_flags & MSG_OOB) |
| 79 | return -EOPNOTSUPP; |
| 80 | |
| 81 | if (msg->msg_name == NULL) |
| 82 | return -EDESTADDRREQ; |
| 83 | |
| 84 | if (msg->msg_namelen < sizeof(struct sockaddr_pn)) |
| 85 | return -EINVAL; |
| 86 | |
| 87 | target = (struct sockaddr_pn *)msg->msg_name; |
| 88 | if (target->spn_family != AF_PHONET) |
| 89 | return -EAFNOSUPPORT; |
| 90 | |
| 91 | skb = sock_alloc_send_skb(sk, MAX_PHONET_HEADER + len, |
| 92 | msg->msg_flags & MSG_DONTWAIT, &err); |
| 93 | if (skb == NULL) |
| 94 | return err; |
| 95 | skb_reserve(skb, MAX_PHONET_HEADER); |
| 96 | |
| 97 | err = memcpy_fromiovec((void *)skb_put(skb, len), msg->msg_iov, len); |
| 98 | if (err < 0) { |
| 99 | kfree_skb(skb); |
| 100 | return err; |
| 101 | } |
| 102 | |
| 103 | /* |
| 104 | * Fill in the Phonet header and |
| 105 | * finally pass the packet forwards. |
| 106 | */ |
| 107 | err = pn_skb_send(sk, skb, target); |
| 108 | |
| 109 | /* If ok, return len. */ |
| 110 | return (err >= 0) ? len : err; |
| 111 | } |
| 112 | |
| 113 | static int pn_recvmsg(struct kiocb *iocb, struct sock *sk, |
| 114 | struct msghdr *msg, size_t len, int noblock, |
| 115 | int flags, int *addr_len) |
| 116 | { |
| 117 | struct sk_buff *skb = NULL; |
| 118 | struct sockaddr_pn sa; |
| 119 | int rval = -EOPNOTSUPP; |
| 120 | int copylen; |
| 121 | |
| 122 | if (flags & MSG_OOB) |
| 123 | goto out_nofree; |
| 124 | |
| 125 | if (addr_len) |
| 126 | *addr_len = sizeof(sa); |
| 127 | |
| 128 | skb = skb_recv_datagram(sk, flags, noblock, &rval); |
| 129 | if (skb == NULL) |
| 130 | goto out_nofree; |
| 131 | |
| 132 | pn_skb_get_src_sockaddr(skb, &sa); |
| 133 | |
| 134 | copylen = skb->len; |
| 135 | if (len < copylen) { |
| 136 | msg->msg_flags |= MSG_TRUNC; |
| 137 | copylen = len; |
| 138 | } |
| 139 | |
| 140 | rval = skb_copy_datagram_iovec(skb, 0, msg->msg_iov, copylen); |
| 141 | if (rval) { |
| 142 | rval = -EFAULT; |
| 143 | goto out; |
| 144 | } |
| 145 | |
| 146 | rval = (flags & MSG_TRUNC) ? skb->len : copylen; |
| 147 | |
| 148 | if (msg->msg_name != NULL) |
| 149 | memcpy(msg->msg_name, &sa, sizeof(struct sockaddr_pn)); |
| 150 | |
| 151 | out: |
| 152 | skb_free_datagram(sk, skb); |
| 153 | |
| 154 | out_nofree: |
| 155 | return rval; |
| 156 | } |
| 157 | |
| 158 | /* Queue an skb for a sock. */ |
| 159 | static int pn_backlog_rcv(struct sock *sk, struct sk_buff *skb) |
| 160 | { |
| 161 | int err = sock_queue_rcv_skb(sk, skb); |
| 162 | if (err < 0) |
| 163 | kfree_skb(skb); |
| 164 | return err ? NET_RX_DROP : NET_RX_SUCCESS; |
| 165 | } |
| 166 | |
| 167 | /* Module registration */ |
| 168 | static struct proto pn_proto = { |
| 169 | .close = pn_sock_close, |
| 170 | .ioctl = pn_ioctl, |
| 171 | .init = pn_init, |
| 172 | .sendmsg = pn_sendmsg, |
| 173 | .recvmsg = pn_recvmsg, |
| 174 | .backlog_rcv = pn_backlog_rcv, |
| 175 | .hash = pn_sock_hash, |
| 176 | .unhash = pn_sock_unhash, |
| 177 | .get_port = pn_sock_get_port, |
| 178 | .obj_size = sizeof(struct pn_sock), |
| 179 | .owner = THIS_MODULE, |
| 180 | .name = "PHONET", |
| 181 | }; |
| 182 | |
| 183 | static struct phonet_protocol pn_dgram_proto = { |
| 184 | .ops = &phonet_dgram_ops, |
| 185 | .prot = &pn_proto, |
| 186 | .sock_type = SOCK_DGRAM, |
| 187 | }; |
| 188 | |
| 189 | int __init isi_register(void) |
| 190 | { |
| 191 | return phonet_proto_register(PN_PROTO_PHONET, &pn_dgram_proto); |
| 192 | } |
| 193 | |
| 194 | void __exit isi_unregister(void) |
| 195 | { |
| 196 | phonet_proto_unregister(PN_PROTO_PHONET, &pn_dgram_proto); |
| 197 | } |