Phonet: allow phonet_device_init() to fail, put it to __init section
[safe/jmp/linux-2.6] / net / phonet / af_phonet.c
index ba54d53..95bc49d 100644 (file)
 #include <net/phonet/phonet.h>
 #include <net/phonet/pn_dev.h>
 
-static struct net_proto_family phonet_proto_family;
-static struct phonet_protocol *phonet_proto_get(int protocol);
-static inline void phonet_proto_put(struct phonet_protocol *pp);
+/* Transport protocol registration */
+static struct phonet_protocol *proto_tab[PHONET_NPROTO] __read_mostly;
+static DEFINE_SPINLOCK(proto_tab_lock);
+
+static struct phonet_protocol *phonet_proto_get(int protocol)
+{
+       struct phonet_protocol *pp;
+
+       if (protocol >= PHONET_NPROTO)
+               return NULL;
+
+       spin_lock(&proto_tab_lock);
+       pp = proto_tab[protocol];
+       if (pp && !try_module_get(pp->prot->owner))
+               pp = NULL;
+       spin_unlock(&proto_tab_lock);
+
+       return pp;
+}
+
+static inline void phonet_proto_put(struct phonet_protocol *pp)
+{
+       module_put(pp->prot->owner);
+}
 
 /* protocol family functions */
 
@@ -46,9 +67,6 @@ static int pn_socket_create(struct net *net, struct socket *sock, int protocol)
        struct phonet_protocol *pnp;
        int err;
 
-       if (net != &init_net)
-               return -EAFNOSUPPORT;
-
        if (!capable(CAP_SYS_ADMIN))
                return -EPERM;
 
@@ -58,12 +76,19 @@ static int pn_socket_create(struct net *net, struct socket *sock, int protocol)
                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) {
@@ -94,11 +119,219 @@ out:
 }
 
 static struct net_proto_family phonet_proto_family = {
-       .family = AF_PHONET,
+       .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 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;
+       }
+
+       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 (pn_addr(src) == pn_addr(dst)) {
+               skb_reset_mac_header(skb);
+               skb->pkt_type = PACKET_LOOPBACK;
+               skb_orphan(skb);
+               if (irq)
+                       netif_rx(skb);
+               else
+                       netif_rx_ni(skb);
+               err = 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);
+       }
+
+       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;
+
+       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_device *dev;
+       struct pn_sock *pn = pn_sk(sk);
+       int err;
+       u16 src;
+       u8 daddr = pn_sockaddr_get_addr(target), saddr = PN_NO_ADDR;
+
+       err = -EHOSTUNREACH;
+       if (sk->sk_bound_dev_if)
+               dev = dev_get_by_index(sock_net(sk), sk->sk_bound_dev_if);
+       else
+               dev = phonet_device_get(sock_net(sk));
+       if (!dev || !(dev->flags & IFF_UP))
+               goto drop;
+
+       saddr = phonet_address_get(dev, daddr);
+       if (saddr == PN_NO_ADDR)
+               goto drop;
+
+       src = pn->sobject;
+       if (!pn_addr(src))
+               src = pn_object(saddr, pn_obj(src));
+
+       err = pn_send(skb, dev, pn_sockaddr_get_object(target),
+                       src, pn_sockaddr_get_resource(target), 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 */
 
 /*
@@ -109,14 +342,11 @@ 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 sock *sk;
        struct sockaddr_pn sa;
        u16 len;
 
-       if (dev_net(dev) != &init_net)
-               goto out;
-
        /* check we have at least a full Phonet header */
        if (!pskb_pull(skb, sizeof(struct phonethdr)))
                goto out;
@@ -132,15 +362,20 @@ static int phonet_rcv(struct sk_buff *skb, struct net_device *dev,
        skb_reset_transport_header(skb);
 
        pn_skb_get_dst_sockaddr(skb, &sa);
-       if (pn_sockaddr_get_addr(&sa) == 0)
-               goto out; /* currently, we cannot be device 0 */
 
-       sk = pn_find_sock_by_sa(&sa);
-       if (sk == NULL)
-               goto out;
+       /* 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);
 
-       /* Push data to the socket (or other sockets connected to it). */
-       return sk_receive_skb(sk, skb, 0);
+               if (sk)
+                       return sk_receive_skb(sk, skb, 0);
+
+               if (can_respond(skb)) {
+                       send_obj_unreachable(skb);
+                       send_reset_indications(skb);
+               }
+       }
 
 out:
        kfree_skb(skb);
@@ -153,10 +388,6 @@ static struct packet_type phonet_packet_type = {
        .func = phonet_rcv,
 };
 
-/* Transport protocol registration */
-static struct phonet_protocol *proto_tab[PHONET_NPROTO] __read_mostly;
-static DEFINE_SPINLOCK(proto_tab_lock);
-
 int __init_or_module phonet_proto_register(int protocol,
                                                struct phonet_protocol *pp)
 {
@@ -190,48 +421,44 @@ void phonet_proto_unregister(int protocol, struct phonet_protocol *pp)
 }
 EXPORT_SYMBOL(phonet_proto_unregister);
 
-static struct phonet_protocol *phonet_proto_get(int protocol)
-{
-       struct phonet_protocol *pp;
-
-       if (protocol >= PHONET_NPROTO)
-               return NULL;
-
-       spin_lock(&proto_tab_lock);
-       pp = proto_tab[protocol];
-       if (pp && !try_module_get(pp->prot->owner))
-               pp = NULL;
-       spin_unlock(&proto_tab_lock);
-
-       return pp;
-}
-
-static inline void phonet_proto_put(struct phonet_protocol *pp)
-{
-       module_put(pp->prot->owner);
-}
-
 /* Module registration */
 static int __init phonet_init(void)
 {
        int err;
 
+       err = phonet_device_init();
+       if (err)
+               return err;
+
        err = sock_register(&phonet_proto_family);
        if (err) {
                printk(KERN_ALERT
                        "phonet protocol family initialization failed\n");
-               return err;
+               goto err_sock;
        }
 
-       phonet_device_init();
        dev_add_pack(&phonet_packet_type);
-       phonet_netlink_register();
+       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)
 {
-       sock_unregister(AF_PHONET);
+       isi_unregister();
+       phonet_sysctl_exit();
+       sock_unregister(PF_PHONET);
        dev_remove_pack(&phonet_packet_type);
        phonet_device_exit();
 }
@@ -240,3 +467,4 @@ module_init(phonet_init);
 module_exit(phonet_exit);
 MODULE_DESCRIPTION("Phonet protocol stack for Linux");
 MODULE_LICENSE("GPL");
+MODULE_ALIAS_NETPROTO(PF_PHONET);