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63d57cd674
Since commit
baebdf48c3
("net: dev: Makes sure netif_rx() can be invoked in any context.")
the function netif_rx() can be used in preemptible/thread context as
well as in interrupt context.
Use netif_rx().
Cc: Remi Denis-Courmont <courmisch@gmail.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
541 lines
12 KiB
C
541 lines
12 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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/*
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* File: af_phonet.c
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*
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* Phonet protocols family
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*
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* Copyright (C) 2008 Nokia Corporation.
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*
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* Authors: Sakari Ailus <sakari.ailus@nokia.com>
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* Rémi Denis-Courmont
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*/
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/slab.h>
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#include <asm/unaligned.h>
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#include <net/sock.h>
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#include <linux/if_phonet.h>
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#include <linux/phonet.h>
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#include <net/phonet/phonet.h>
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#include <net/phonet/pn_dev.h>
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/* Transport protocol registration */
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static const struct phonet_protocol *proto_tab[PHONET_NPROTO] __read_mostly;
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static const struct phonet_protocol *phonet_proto_get(unsigned int protocol)
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{
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const struct phonet_protocol *pp;
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if (protocol >= PHONET_NPROTO)
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return NULL;
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rcu_read_lock();
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pp = rcu_dereference(proto_tab[protocol]);
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if (pp && !try_module_get(pp->prot->owner))
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pp = NULL;
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rcu_read_unlock();
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return pp;
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}
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static inline void phonet_proto_put(const struct phonet_protocol *pp)
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{
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module_put(pp->prot->owner);
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}
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/* protocol family functions */
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static int pn_socket_create(struct net *net, struct socket *sock, int protocol,
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int kern)
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{
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struct sock *sk;
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struct pn_sock *pn;
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const struct phonet_protocol *pnp;
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int err;
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if (!capable(CAP_SYS_ADMIN))
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return -EPERM;
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if (protocol == 0) {
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/* Default protocol selection */
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switch (sock->type) {
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case SOCK_DGRAM:
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protocol = PN_PROTO_PHONET;
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break;
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case SOCK_SEQPACKET:
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protocol = PN_PROTO_PIPE;
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break;
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default:
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return -EPROTONOSUPPORT;
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}
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}
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pnp = phonet_proto_get(protocol);
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if (pnp == NULL &&
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request_module("net-pf-%d-proto-%d", PF_PHONET, protocol) == 0)
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pnp = phonet_proto_get(protocol);
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if (pnp == NULL)
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return -EPROTONOSUPPORT;
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if (sock->type != pnp->sock_type) {
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err = -EPROTONOSUPPORT;
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goto out;
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}
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sk = sk_alloc(net, PF_PHONET, GFP_KERNEL, pnp->prot, kern);
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if (sk == NULL) {
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err = -ENOMEM;
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goto out;
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}
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sock_init_data(sock, sk);
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sock->state = SS_UNCONNECTED;
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sock->ops = pnp->ops;
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sk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
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sk->sk_protocol = protocol;
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pn = pn_sk(sk);
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pn->sobject = 0;
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pn->dobject = 0;
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pn->resource = 0;
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sk->sk_prot->init(sk);
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err = 0;
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out:
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phonet_proto_put(pnp);
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return err;
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}
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static const struct net_proto_family phonet_proto_family = {
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.family = PF_PHONET,
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.create = pn_socket_create,
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.owner = THIS_MODULE,
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};
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/* Phonet device header operations */
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static int pn_header_create(struct sk_buff *skb, struct net_device *dev,
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unsigned short type, const void *daddr,
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const void *saddr, unsigned int len)
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{
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u8 *media = skb_push(skb, 1);
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if (type != ETH_P_PHONET)
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return -1;
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if (!saddr)
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saddr = dev->dev_addr;
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*media = *(const u8 *)saddr;
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return 1;
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}
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static int pn_header_parse(const struct sk_buff *skb, unsigned char *haddr)
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{
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const u8 *media = skb_mac_header(skb);
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*haddr = *media;
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return 1;
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}
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const struct header_ops phonet_header_ops = {
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.create = pn_header_create,
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.parse = pn_header_parse,
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};
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EXPORT_SYMBOL(phonet_header_ops);
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/*
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* Prepends an ISI header and sends a datagram.
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*/
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static int pn_send(struct sk_buff *skb, struct net_device *dev,
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u16 dst, u16 src, u8 res)
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{
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struct phonethdr *ph;
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int err;
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if (skb->len + 2 > 0xffff /* Phonet length field limit */ ||
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skb->len + sizeof(struct phonethdr) > dev->mtu) {
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err = -EMSGSIZE;
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goto drop;
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}
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/* Broadcast sending is not implemented */
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if (pn_addr(dst) == PNADDR_BROADCAST) {
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err = -EOPNOTSUPP;
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goto drop;
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}
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skb_reset_transport_header(skb);
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WARN_ON(skb_headroom(skb) & 1); /* HW assumes word alignment */
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skb_push(skb, sizeof(struct phonethdr));
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skb_reset_network_header(skb);
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ph = pn_hdr(skb);
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ph->pn_rdev = pn_dev(dst);
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ph->pn_sdev = pn_dev(src);
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ph->pn_res = res;
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ph->pn_length = __cpu_to_be16(skb->len + 2 - sizeof(*ph));
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ph->pn_robj = pn_obj(dst);
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ph->pn_sobj = pn_obj(src);
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skb->protocol = htons(ETH_P_PHONET);
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skb->priority = 0;
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skb->dev = dev;
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if (skb->pkt_type == PACKET_LOOPBACK) {
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skb_reset_mac_header(skb);
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skb_orphan(skb);
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err = netif_rx(skb) ? -ENOBUFS : 0;
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} else {
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err = dev_hard_header(skb, dev, ntohs(skb->protocol),
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NULL, NULL, skb->len);
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if (err < 0) {
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err = -EHOSTUNREACH;
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goto drop;
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}
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err = dev_queue_xmit(skb);
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if (unlikely(err > 0))
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err = net_xmit_errno(err);
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}
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return err;
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drop:
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kfree_skb(skb);
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return err;
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}
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static int pn_raw_send(const void *data, int len, struct net_device *dev,
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u16 dst, u16 src, u8 res)
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{
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struct sk_buff *skb = alloc_skb(MAX_PHONET_HEADER + len, GFP_ATOMIC);
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if (skb == NULL)
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return -ENOMEM;
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if (phonet_address_lookup(dev_net(dev), pn_addr(dst)) == 0)
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skb->pkt_type = PACKET_LOOPBACK;
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skb_reserve(skb, MAX_PHONET_HEADER);
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__skb_put(skb, len);
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skb_copy_to_linear_data(skb, data, len);
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return pn_send(skb, dev, dst, src, res);
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}
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/*
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* Create a Phonet header for the skb and send it out. Returns
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* non-zero error code if failed. The skb is freed then.
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*/
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int pn_skb_send(struct sock *sk, struct sk_buff *skb,
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const struct sockaddr_pn *target)
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{
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struct net *net = sock_net(sk);
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struct net_device *dev;
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struct pn_sock *pn = pn_sk(sk);
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int err;
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u16 src, dst;
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u8 daddr, saddr, res;
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src = pn->sobject;
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if (target != NULL) {
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dst = pn_sockaddr_get_object(target);
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res = pn_sockaddr_get_resource(target);
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} else {
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dst = pn->dobject;
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res = pn->resource;
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}
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daddr = pn_addr(dst);
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err = -EHOSTUNREACH;
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if (sk->sk_bound_dev_if)
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dev = dev_get_by_index(net, sk->sk_bound_dev_if);
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else if (phonet_address_lookup(net, daddr) == 0) {
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dev = phonet_device_get(net);
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skb->pkt_type = PACKET_LOOPBACK;
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} else if (dst == 0) {
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/* Resource routing (small race until phonet_rcv()) */
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struct sock *sk = pn_find_sock_by_res(net, res);
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if (sk) {
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sock_put(sk);
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dev = phonet_device_get(net);
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skb->pkt_type = PACKET_LOOPBACK;
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} else
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dev = phonet_route_output(net, daddr);
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} else
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dev = phonet_route_output(net, daddr);
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if (!dev || !(dev->flags & IFF_UP))
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goto drop;
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saddr = phonet_address_get(dev, daddr);
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if (saddr == PN_NO_ADDR)
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goto drop;
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if (!pn_addr(src))
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src = pn_object(saddr, pn_obj(src));
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err = pn_send(skb, dev, dst, src, res);
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dev_put(dev);
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return err;
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drop:
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kfree_skb(skb);
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dev_put(dev);
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return err;
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}
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EXPORT_SYMBOL(pn_skb_send);
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/* Do not send an error message in response to an error message */
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static inline int can_respond(struct sk_buff *skb)
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{
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const struct phonethdr *ph;
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const struct phonetmsg *pm;
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u8 submsg_id;
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if (!pskb_may_pull(skb, 3))
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return 0;
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ph = pn_hdr(skb);
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if (ph->pn_res == PN_PREFIX && !pskb_may_pull(skb, 5))
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return 0;
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if (ph->pn_res == PN_COMMGR) /* indications */
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return 0;
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ph = pn_hdr(skb); /* re-acquires the pointer */
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pm = pn_msg(skb);
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if (pm->pn_msg_id != PN_COMMON_MESSAGE)
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return 1;
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submsg_id = (ph->pn_res == PN_PREFIX)
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? pm->pn_e_submsg_id : pm->pn_submsg_id;
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if (submsg_id != PN_COMM_ISA_ENTITY_NOT_REACHABLE_RESP &&
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pm->pn_e_submsg_id != PN_COMM_SERVICE_NOT_IDENTIFIED_RESP)
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return 1;
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return 0;
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}
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static int send_obj_unreachable(struct sk_buff *rskb)
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{
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const struct phonethdr *oph = pn_hdr(rskb);
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const struct phonetmsg *opm = pn_msg(rskb);
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struct phonetmsg resp;
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memset(&resp, 0, sizeof(resp));
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resp.pn_trans_id = opm->pn_trans_id;
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resp.pn_msg_id = PN_COMMON_MESSAGE;
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if (oph->pn_res == PN_PREFIX) {
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resp.pn_e_res_id = opm->pn_e_res_id;
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resp.pn_e_submsg_id = PN_COMM_ISA_ENTITY_NOT_REACHABLE_RESP;
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resp.pn_e_orig_msg_id = opm->pn_msg_id;
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resp.pn_e_status = 0;
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} else {
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resp.pn_submsg_id = PN_COMM_ISA_ENTITY_NOT_REACHABLE_RESP;
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resp.pn_orig_msg_id = opm->pn_msg_id;
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resp.pn_status = 0;
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}
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return pn_raw_send(&resp, sizeof(resp), rskb->dev,
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pn_object(oph->pn_sdev, oph->pn_sobj),
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pn_object(oph->pn_rdev, oph->pn_robj),
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oph->pn_res);
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}
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static int send_reset_indications(struct sk_buff *rskb)
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{
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struct phonethdr *oph = pn_hdr(rskb);
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static const u8 data[4] = {
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0x00 /* trans ID */, 0x10 /* subscribe msg */,
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0x00 /* subscription count */, 0x00 /* dummy */
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};
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return pn_raw_send(data, sizeof(data), rskb->dev,
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pn_object(oph->pn_sdev, 0x00),
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pn_object(oph->pn_rdev, oph->pn_robj),
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PN_COMMGR);
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}
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/* packet type functions */
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/*
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* Stuff received packets to associated sockets.
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* On error, returns non-zero and releases the skb.
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*/
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static int phonet_rcv(struct sk_buff *skb, struct net_device *dev,
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struct packet_type *pkttype,
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struct net_device *orig_dev)
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{
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struct net *net = dev_net(dev);
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struct phonethdr *ph;
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struct sockaddr_pn sa;
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u16 len;
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skb = skb_share_check(skb, GFP_ATOMIC);
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if (!skb)
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return NET_RX_DROP;
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/* check we have at least a full Phonet header */
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if (!pskb_pull(skb, sizeof(struct phonethdr)))
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goto out;
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/* check that the advertised length is correct */
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ph = pn_hdr(skb);
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len = get_unaligned_be16(&ph->pn_length);
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if (len < 2)
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goto out;
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len -= 2;
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if ((len > skb->len) || pskb_trim(skb, len))
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goto out;
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skb_reset_transport_header(skb);
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pn_skb_get_dst_sockaddr(skb, &sa);
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/* check if this is broadcasted */
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if (pn_sockaddr_get_addr(&sa) == PNADDR_BROADCAST) {
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pn_deliver_sock_broadcast(net, skb);
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goto out;
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}
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/* resource routing */
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if (pn_sockaddr_get_object(&sa) == 0) {
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struct sock *sk = pn_find_sock_by_res(net, sa.spn_resource);
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if (sk)
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return sk_receive_skb(sk, skb, 0);
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}
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|
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/* check if we are the destination */
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if (phonet_address_lookup(net, pn_sockaddr_get_addr(&sa)) == 0) {
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/* Phonet packet input */
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struct sock *sk = pn_find_sock_by_sa(net, &sa);
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|
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if (sk)
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return sk_receive_skb(sk, skb, 0);
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if (can_respond(skb)) {
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send_obj_unreachable(skb);
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send_reset_indications(skb);
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}
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} else if (unlikely(skb->pkt_type == PACKET_LOOPBACK))
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goto out; /* Race between address deletion and loopback */
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else {
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/* Phonet packet routing */
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struct net_device *out_dev;
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out_dev = phonet_route_output(net, pn_sockaddr_get_addr(&sa));
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if (!out_dev) {
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net_dbg_ratelimited("No Phonet route to %02X\n",
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pn_sockaddr_get_addr(&sa));
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goto out;
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}
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__skb_push(skb, sizeof(struct phonethdr));
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skb->dev = out_dev;
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if (out_dev == dev) {
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net_dbg_ratelimited("Phonet loop to %02X on %s\n",
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pn_sockaddr_get_addr(&sa),
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dev->name);
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goto out_dev;
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}
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/* Some drivers (e.g. TUN) do not allocate HW header space */
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if (skb_cow_head(skb, out_dev->hard_header_len))
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goto out_dev;
|
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|
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if (dev_hard_header(skb, out_dev, ETH_P_PHONET, NULL, NULL,
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skb->len) < 0)
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goto out_dev;
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dev_queue_xmit(skb);
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dev_put(out_dev);
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return NET_RX_SUCCESS;
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out_dev:
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dev_put(out_dev);
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}
|
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|
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out:
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kfree_skb(skb);
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return NET_RX_DROP;
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}
|
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|
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static struct packet_type phonet_packet_type __read_mostly = {
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.type = cpu_to_be16(ETH_P_PHONET),
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.func = phonet_rcv,
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};
|
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|
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static DEFINE_MUTEX(proto_tab_lock);
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|
|
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int __init_or_module phonet_proto_register(unsigned int protocol,
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const struct phonet_protocol *pp)
|
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{
|
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int err = 0;
|
|
|
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if (protocol >= PHONET_NPROTO)
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return -EINVAL;
|
|
|
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err = proto_register(pp->prot, 1);
|
|
if (err)
|
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return err;
|
|
|
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mutex_lock(&proto_tab_lock);
|
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if (proto_tab[protocol])
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err = -EBUSY;
|
|
else
|
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rcu_assign_pointer(proto_tab[protocol], pp);
|
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mutex_unlock(&proto_tab_lock);
|
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|
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return err;
|
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}
|
|
EXPORT_SYMBOL(phonet_proto_register);
|
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|
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void phonet_proto_unregister(unsigned int protocol,
|
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const struct phonet_protocol *pp)
|
|
{
|
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mutex_lock(&proto_tab_lock);
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BUG_ON(proto_tab[protocol] != pp);
|
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RCU_INIT_POINTER(proto_tab[protocol], NULL);
|
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mutex_unlock(&proto_tab_lock);
|
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synchronize_rcu();
|
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proto_unregister(pp->prot);
|
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}
|
|
EXPORT_SYMBOL(phonet_proto_unregister);
|
|
|
|
/* Module registration */
|
|
static int __init phonet_init(void)
|
|
{
|
|
int err;
|
|
|
|
err = phonet_device_init();
|
|
if (err)
|
|
return err;
|
|
|
|
pn_sock_init();
|
|
err = sock_register(&phonet_proto_family);
|
|
if (err) {
|
|
printk(KERN_ALERT
|
|
"phonet protocol family initialization failed\n");
|
|
goto err_sock;
|
|
}
|
|
|
|
dev_add_pack(&phonet_packet_type);
|
|
phonet_sysctl_init();
|
|
|
|
err = isi_register();
|
|
if (err)
|
|
goto err;
|
|
return 0;
|
|
|
|
err:
|
|
phonet_sysctl_exit();
|
|
sock_unregister(PF_PHONET);
|
|
dev_remove_pack(&phonet_packet_type);
|
|
err_sock:
|
|
phonet_device_exit();
|
|
return err;
|
|
}
|
|
|
|
static void __exit phonet_exit(void)
|
|
{
|
|
isi_unregister();
|
|
phonet_sysctl_exit();
|
|
sock_unregister(PF_PHONET);
|
|
dev_remove_pack(&phonet_packet_type);
|
|
phonet_device_exit();
|
|
}
|
|
|
|
module_init(phonet_init);
|
|
module_exit(phonet_exit);
|
|
MODULE_DESCRIPTION("Phonet protocol stack for Linux");
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_ALIAS_NETPROTO(PF_PHONET);
|