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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /net/phonet/af_phonet.c
Initial import
Diffstat (limited to 'net/phonet/af_phonet.c')
-rw-r--r--net/phonet/af_phonet.c549
1 files changed, 549 insertions, 0 deletions
diff --git a/net/phonet/af_phonet.c b/net/phonet/af_phonet.c
new file mode 100644
index 000000000..32ab87d34
--- /dev/null
+++ b/net/phonet/af_phonet.c
@@ -0,0 +1,549 @@
+/*
+ * File: af_phonet.c
+ *
+ * Phonet protocols family
+ *
+ * Copyright (C) 2008 Nokia Corporation.
+ *
+ * Authors: Sakari Ailus <sakari.ailus@nokia.com>
+ * 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/module.h>
+#include <linux/slab.h>
+#include <asm/unaligned.h>
+#include <net/sock.h>
+
+#include <linux/if_phonet.h>
+#include <linux/phonet.h>
+#include <net/phonet/phonet.h>
+#include <net/phonet/pn_dev.h>
+
+/* Transport protocol registration */
+static struct phonet_protocol *proto_tab[PHONET_NPROTO] __read_mostly;
+
+static struct phonet_protocol *phonet_proto_get(unsigned int protocol)
+{
+ struct phonet_protocol *pp;
+
+ if (protocol >= PHONET_NPROTO)
+ return NULL;
+
+ rcu_read_lock();
+ pp = rcu_dereference(proto_tab[protocol]);
+ if (pp && !try_module_get(pp->prot->owner))
+ pp = NULL;
+ rcu_read_unlock();
+
+ return pp;
+}
+
+static inline void phonet_proto_put(struct phonet_protocol *pp)
+{
+ module_put(pp->prot->owner);
+}
+
+/* protocol family functions */
+
+static int pn_socket_create(struct net *net, struct socket *sock, int protocol,
+ int kern)
+{
+ struct sock *sk;
+ struct pn_sock *pn;
+ struct phonet_protocol *pnp;
+ int err;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ if (protocol == 0) {
+ /* Default protocol selection */
+ switch (sock->type) {
+ case SOCK_DGRAM:
+ protocol = PN_PROTO_PHONET;
+ break;
+ case SOCK_SEQPACKET:
+ protocol = PN_PROTO_PIPE;
+ break;
+ default:
+ return -EPROTONOSUPPORT;
+ }
+ }
+
+ pnp = phonet_proto_get(protocol);
+ if (pnp == NULL &&
+ request_module("net-pf-%d-proto-%d", PF_PHONET, protocol) == 0)
+ pnp = phonet_proto_get(protocol);
+
+ if (pnp == NULL)
+ return -EPROTONOSUPPORT;
+ if (sock->type != pnp->sock_type) {
+ err = -EPROTONOSUPPORT;
+ goto out;
+ }
+
+ sk = sk_alloc(net, PF_PHONET, GFP_KERNEL, pnp->prot);
+ if (sk == NULL) {
+ err = -ENOMEM;
+ goto out;
+ }
+
+ sock_init_data(sock, sk);
+ sock->state = SS_UNCONNECTED;
+ sock->ops = pnp->ops;
+ sk->sk_backlog_rcv = sk->sk_prot->backlog_rcv;
+ sk->sk_protocol = protocol;
+ pn = pn_sk(sk);
+ pn->sobject = 0;
+ pn->dobject = 0;
+ pn->resource = 0;
+ sk->sk_prot->init(sk);
+ err = 0;
+
+out:
+ phonet_proto_put(pnp);
+ return err;
+}
+
+static const struct net_proto_family phonet_proto_family = {
+ .family = PF_PHONET,
+ .create = pn_socket_create,
+ .owner = THIS_MODULE,
+};
+
+/* Phonet device header operations */
+static int pn_header_create(struct sk_buff *skb, struct net_device *dev,
+ unsigned short type, const void *daddr,
+ const void *saddr, unsigned int len)
+{
+ u8 *media = skb_push(skb, 1);
+
+ if (type != ETH_P_PHONET)
+ return -1;
+
+ if (!saddr)
+ saddr = dev->dev_addr;
+ *media = *(const u8 *)saddr;
+ return 1;
+}
+
+static int pn_header_parse(const struct sk_buff *skb, unsigned char *haddr)
+{
+ const u8 *media = skb_mac_header(skb);
+ *haddr = *media;
+ return 1;
+}
+
+struct header_ops phonet_header_ops = {
+ .create = pn_header_create,
+ .parse = pn_header_parse,
+};
+EXPORT_SYMBOL(phonet_header_ops);
+
+/*
+ * Prepends an ISI header and sends a datagram.
+ */
+static int pn_send(struct sk_buff *skb, struct net_device *dev,
+ u16 dst, u16 src, u8 res, u8 irq)
+{
+ struct phonethdr *ph;
+ int err;
+
+ if (skb->len + 2 > 0xffff /* Phonet length field limit */ ||
+ skb->len + sizeof(struct phonethdr) > dev->mtu) {
+ err = -EMSGSIZE;
+ goto drop;
+ }
+
+ /* Broadcast sending is not implemented */
+ if (pn_addr(dst) == PNADDR_BROADCAST) {
+ err = -EOPNOTSUPP;
+ goto drop;
+ }
+
+ skb_reset_transport_header(skb);
+ WARN_ON(skb_headroom(skb) & 1); /* HW assumes word alignment */
+ skb_push(skb, sizeof(struct phonethdr));
+ skb_reset_network_header(skb);
+ ph = pn_hdr(skb);
+ ph->pn_rdev = pn_dev(dst);
+ ph->pn_sdev = pn_dev(src);
+ ph->pn_res = res;
+ ph->pn_length = __cpu_to_be16(skb->len + 2 - sizeof(*ph));
+ ph->pn_robj = pn_obj(dst);
+ ph->pn_sobj = pn_obj(src);
+
+ skb->protocol = htons(ETH_P_PHONET);
+ skb->priority = 0;
+ skb->dev = dev;
+
+ if (skb->pkt_type == PACKET_LOOPBACK) {
+ skb_reset_mac_header(skb);
+ skb_orphan(skb);
+ err = (irq ? netif_rx(skb) : netif_rx_ni(skb)) ? -ENOBUFS : 0;
+ } else {
+ err = dev_hard_header(skb, dev, ntohs(skb->protocol),
+ NULL, NULL, skb->len);
+ if (err < 0) {
+ err = -EHOSTUNREACH;
+ goto drop;
+ }
+ err = dev_queue_xmit(skb);
+ if (unlikely(err > 0))
+ err = net_xmit_errno(err);
+ }
+
+ return err;
+drop:
+ kfree_skb(skb);
+ return err;
+}
+
+static int pn_raw_send(const void *data, int len, struct net_device *dev,
+ u16 dst, u16 src, u8 res)
+{
+ struct sk_buff *skb = alloc_skb(MAX_PHONET_HEADER + len, GFP_ATOMIC);
+ if (skb == NULL)
+ return -ENOMEM;
+
+ if (phonet_address_lookup(dev_net(dev), pn_addr(dst)) == 0)
+ skb->pkt_type = PACKET_LOOPBACK;
+
+ skb_reserve(skb, MAX_PHONET_HEADER);
+ __skb_put(skb, len);
+ skb_copy_to_linear_data(skb, data, len);
+ return pn_send(skb, dev, dst, src, res, 1);
+}
+
+/*
+ * Create a Phonet header for the skb and send it out. Returns
+ * non-zero error code if failed. The skb is freed then.
+ */
+int pn_skb_send(struct sock *sk, struct sk_buff *skb,
+ const struct sockaddr_pn *target)
+{
+ struct net *net = sock_net(sk);
+ struct net_device *dev;
+ struct pn_sock *pn = pn_sk(sk);
+ int err;
+ u16 src, dst;
+ u8 daddr, saddr, res;
+
+ src = pn->sobject;
+ if (target != NULL) {
+ dst = pn_sockaddr_get_object(target);
+ res = pn_sockaddr_get_resource(target);
+ } else {
+ dst = pn->dobject;
+ res = pn->resource;
+ }
+ daddr = pn_addr(dst);
+
+ err = -EHOSTUNREACH;
+ if (sk->sk_bound_dev_if)
+ dev = dev_get_by_index(net, sk->sk_bound_dev_if);
+ else if (phonet_address_lookup(net, daddr) == 0) {
+ dev = phonet_device_get(net);
+ skb->pkt_type = PACKET_LOOPBACK;
+ } else if (dst == 0) {
+ /* Resource routing (small race until phonet_rcv()) */
+ struct sock *sk = pn_find_sock_by_res(net, res);
+ if (sk) {
+ sock_put(sk);
+ dev = phonet_device_get(net);
+ skb->pkt_type = PACKET_LOOPBACK;
+ } else
+ dev = phonet_route_output(net, daddr);
+ } else
+ dev = phonet_route_output(net, daddr);
+
+ if (!dev || !(dev->flags & IFF_UP))
+ goto drop;
+
+ saddr = phonet_address_get(dev, daddr);
+ if (saddr == PN_NO_ADDR)
+ goto drop;
+
+ if (!pn_addr(src))
+ src = pn_object(saddr, pn_obj(src));
+
+ err = pn_send(skb, dev, dst, src, res, 0);
+ dev_put(dev);
+ return err;
+
+drop:
+ kfree_skb(skb);
+ if (dev)
+ dev_put(dev);
+ return err;
+}
+EXPORT_SYMBOL(pn_skb_send);
+
+/* Do not send an error message in response to an error message */
+static inline int can_respond(struct sk_buff *skb)
+{
+ const struct phonethdr *ph;
+ const struct phonetmsg *pm;
+ u8 submsg_id;
+
+ if (!pskb_may_pull(skb, 3))
+ return 0;
+
+ ph = pn_hdr(skb);
+ if (ph->pn_res == PN_PREFIX && !pskb_may_pull(skb, 5))
+ return 0;
+ if (ph->pn_res == PN_COMMGR) /* indications */
+ return 0;
+
+ ph = pn_hdr(skb); /* re-acquires the pointer */
+ pm = pn_msg(skb);
+ if (pm->pn_msg_id != PN_COMMON_MESSAGE)
+ return 1;
+ submsg_id = (ph->pn_res == PN_PREFIX)
+ ? pm->pn_e_submsg_id : pm->pn_submsg_id;
+ if (submsg_id != PN_COMM_ISA_ENTITY_NOT_REACHABLE_RESP &&
+ pm->pn_e_submsg_id != PN_COMM_SERVICE_NOT_IDENTIFIED_RESP)
+ return 1;
+ return 0;
+}
+
+static int send_obj_unreachable(struct sk_buff *rskb)
+{
+ const struct phonethdr *oph = pn_hdr(rskb);
+ const struct phonetmsg *opm = pn_msg(rskb);
+ struct phonetmsg resp;
+
+ memset(&resp, 0, sizeof(resp));
+ resp.pn_trans_id = opm->pn_trans_id;
+ resp.pn_msg_id = PN_COMMON_MESSAGE;
+ if (oph->pn_res == PN_PREFIX) {
+ resp.pn_e_res_id = opm->pn_e_res_id;
+ resp.pn_e_submsg_id = PN_COMM_ISA_ENTITY_NOT_REACHABLE_RESP;
+ resp.pn_e_orig_msg_id = opm->pn_msg_id;
+ resp.pn_e_status = 0;
+ } else {
+ resp.pn_submsg_id = PN_COMM_ISA_ENTITY_NOT_REACHABLE_RESP;
+ resp.pn_orig_msg_id = opm->pn_msg_id;
+ resp.pn_status = 0;
+ }
+ return pn_raw_send(&resp, sizeof(resp), rskb->dev,
+ pn_object(oph->pn_sdev, oph->pn_sobj),
+ pn_object(oph->pn_rdev, oph->pn_robj),
+ oph->pn_res);
+}
+
+static int send_reset_indications(struct sk_buff *rskb)
+{
+ struct phonethdr *oph = pn_hdr(rskb);
+ static const u8 data[4] = {
+ 0x00 /* trans ID */, 0x10 /* subscribe msg */,
+ 0x00 /* subscription count */, 0x00 /* dummy */
+ };
+
+ return pn_raw_send(data, sizeof(data), rskb->dev,
+ pn_object(oph->pn_sdev, 0x00),
+ pn_object(oph->pn_rdev, oph->pn_robj),
+ PN_COMMGR);
+}
+
+
+/* packet type functions */
+
+/*
+ * Stuff received packets to associated sockets.
+ * On error, returns non-zero and releases the skb.
+ */
+static int phonet_rcv(struct sk_buff *skb, struct net_device *dev,
+ struct packet_type *pkttype,
+ struct net_device *orig_dev)
+{
+ struct net *net = dev_net(dev);
+ struct phonethdr *ph;
+ struct sockaddr_pn sa;
+ u16 len;
+
+ /* check we have at least a full Phonet header */
+ if (!pskb_pull(skb, sizeof(struct phonethdr)))
+ goto out;
+
+ /* check that the advertised length is correct */
+ ph = pn_hdr(skb);
+ len = get_unaligned_be16(&ph->pn_length);
+ if (len < 2)
+ goto out;
+ len -= 2;
+ if ((len > skb->len) || pskb_trim(skb, len))
+ goto out;
+ skb_reset_transport_header(skb);
+
+ pn_skb_get_dst_sockaddr(skb, &sa);
+
+ /* check if this is broadcasted */
+ if (pn_sockaddr_get_addr(&sa) == PNADDR_BROADCAST) {
+ pn_deliver_sock_broadcast(net, skb);
+ goto out;
+ }
+
+ /* resource routing */
+ if (pn_sockaddr_get_object(&sa) == 0) {
+ struct sock *sk = pn_find_sock_by_res(net, sa.spn_resource);
+ if (sk)
+ return sk_receive_skb(sk, skb, 0);
+ }
+
+ /* check if we are the destination */
+ if (phonet_address_lookup(net, pn_sockaddr_get_addr(&sa)) == 0) {
+ /* Phonet packet input */
+ struct sock *sk = pn_find_sock_by_sa(net, &sa);
+
+ if (sk)
+ return sk_receive_skb(sk, skb, 0);
+
+ if (can_respond(skb)) {
+ send_obj_unreachable(skb);
+ send_reset_indications(skb);
+ }
+ } else if (unlikely(skb->pkt_type == PACKET_LOOPBACK))
+ goto out; /* Race between address deletion and loopback */
+ else {
+ /* Phonet packet routing */
+ struct net_device *out_dev;
+
+ out_dev = phonet_route_output(net, pn_sockaddr_get_addr(&sa));
+ if (!out_dev) {
+ net_dbg_ratelimited("No Phonet route to %02X\n",
+ pn_sockaddr_get_addr(&sa));
+ goto out;
+ }
+
+ __skb_push(skb, sizeof(struct phonethdr));
+ skb->dev = out_dev;
+ if (out_dev == dev) {
+ net_dbg_ratelimited("Phonet loop to %02X on %s\n",
+ pn_sockaddr_get_addr(&sa),
+ dev->name);
+ goto out_dev;
+ }
+ /* Some drivers (e.g. TUN) do not allocate HW header space */
+ if (skb_cow_head(skb, out_dev->hard_header_len))
+ goto out_dev;
+
+ if (dev_hard_header(skb, out_dev, ETH_P_PHONET, NULL, NULL,
+ skb->len) < 0)
+ goto out_dev;
+ dev_queue_xmit(skb);
+ dev_put(out_dev);
+ return NET_RX_SUCCESS;
+out_dev:
+ dev_put(out_dev);
+ }
+
+out:
+ kfree_skb(skb);
+ return NET_RX_DROP;
+}
+
+static struct packet_type phonet_packet_type __read_mostly = {
+ .type = cpu_to_be16(ETH_P_PHONET),
+ .func = phonet_rcv,
+};
+
+static DEFINE_MUTEX(proto_tab_lock);
+
+int __init_or_module phonet_proto_register(unsigned int protocol,
+ struct phonet_protocol *pp)
+{
+ int err = 0;
+
+ if (protocol >= PHONET_NPROTO)
+ return -EINVAL;
+
+ err = proto_register(pp->prot, 1);
+ if (err)
+ return err;
+
+ mutex_lock(&proto_tab_lock);
+ if (proto_tab[protocol])
+ err = -EBUSY;
+ else
+ rcu_assign_pointer(proto_tab[protocol], pp);
+ mutex_unlock(&proto_tab_lock);
+
+ return err;
+}
+EXPORT_SYMBOL(phonet_proto_register);
+
+void phonet_proto_unregister(unsigned int protocol, struct phonet_protocol *pp)
+{
+ mutex_lock(&proto_tab_lock);
+ BUG_ON(proto_tab[protocol] != pp);
+ RCU_INIT_POINTER(proto_tab[protocol], NULL);
+ mutex_unlock(&proto_tab_lock);
+ synchronize_rcu();
+ proto_unregister(pp->prot);
+}
+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);