/* * Interface to ax25_link_up. Changes my level 2 callsign depending * on whether we have a global ROSE callsign or use the default port * callsign. */ static int rose_link_up(struct rose_neigh *neigh) { ax25_address *rose_call; ax25_cb *ax25s; if (ax25cmp(&rose_callsign, &null_ax25_address) == 0) rose_call = (ax25_address *)neigh->dev->dev_addr; else rose_call = &rose_callsign; ax25s = neigh->ax25; neigh->ax25 = ax25_find_cb(rose_call, &neigh->callsign, neigh->digipeat, neigh->dev); if (ax25s) ax25_cb_put(ax25s); return neigh->ax25 != NULL; }
/* * Interface to ax25_send_frame. Changes my level 2 callsign depending * on whether we have a global ROSE callsign or use the default port * callsign. */ static int rose_send_frame(struct sk_buff *skb, struct rose_neigh *neigh) { ax25_address *rose_call; ax25_cb *ax25s; if (ax25cmp(&rose_callsign, &null_ax25_address) == 0) rose_call = (ax25_address *)neigh->dev->dev_addr; else rose_call = &rose_callsign; ax25s = neigh->ax25; neigh->ax25 = ax25_send_frame(skb, 260, rose_call, &neigh->callsign, neigh->digipeat, neigh->dev); if (ax25s) ax25_cb_put(ax25s); return neigh->ax25 != NULL; }
ax25_cb *ax25_send_frame(struct sk_buff *skb, int paclen, ax25_address *src, ax25_address *dest, ax25_digi *digi, struct net_device *dev) { ax25_dev *ax25_dev; ax25_cb *ax25; /* * Take the default packet length for the device if zero is * specified. */ if (paclen == 0) { if ((ax25_dev = ax25_dev_ax25dev(dev)) == NULL) return NULL; paclen = ax25_dev->values[AX25_VALUES_PACLEN]; } /* * Look for an existing connection. */ if ((ax25 = ax25_find_cb(src, dest, digi, dev)) != NULL) { ax25_output(ax25, paclen, skb); return ax25; /* It already existed */ } if ((ax25_dev = ax25_dev_ax25dev(dev)) == NULL) return NULL; if ((ax25 = ax25_create_cb()) == NULL) return NULL; ax25_fillin_cb(ax25, ax25_dev); ax25->source_addr = *src; ax25->dest_addr = *dest; if (digi != NULL) { ax25->digipeat = kmemdup(digi, sizeof(*digi), GFP_ATOMIC); if (ax25->digipeat == NULL) { ax25_cb_put(ax25); return NULL; } } switch (ax25->ax25_dev->values[AX25_VALUES_PROTOCOL]) { case AX25_PROTO_STD_SIMPLEX: case AX25_PROTO_STD_DUPLEX: ax25_std_establish_data_link(ax25); break; #ifdef CONFIG_AX25_DAMA_SLAVE case AX25_PROTO_DAMA_SLAVE: if (ax25_dev->dama.slave) ax25_ds_establish_data_link(ax25); else ax25_std_establish_data_link(ax25); break; #endif } /* * There is one ref for the state machine; a caller needs * one more to put it back, just like with the existing one. */ ax25_cb_hold(ax25); ax25_cb_add(ax25); ax25->state = AX25_STATE_1; ax25_start_heartbeat(ax25); ax25_output(ax25, paclen, skb); return ax25; /* We had to create it */ }
static int ax25_rcv(struct sk_buff *skb, struct net_device *dev, ax25_address *dev_addr, struct packet_type *ptype) { ax25_address src, dest, *next_digi = NULL; int type = 0, mine = 0, dama; struct sock *make, *sk; ax25_digi dp, reverse_dp; ax25_cb *ax25; ax25_dev *ax25_dev; /* * Process the AX.25/LAPB frame. */ skb_reset_transport_header(skb); if ((ax25_dev = ax25_dev_ax25dev(dev)) == NULL) { kfree_skb(skb); return 0; } /* * Parse the address header. */ if (ax25_addr_parse(skb->data, skb->len, &src, &dest, &dp, &type, &dama) == NULL) { kfree_skb(skb); return 0; } /* * Ours perhaps ? */ if (dp.lastrepeat + 1 < dp.ndigi) /* Not yet digipeated completely */ next_digi = &dp.calls[dp.lastrepeat + 1]; /* * Pull of the AX.25 headers leaving the CTRL/PID bytes */ skb_pull(skb, ax25_addr_size(&dp)); /* For our port addresses ? */ if (ax25cmp(&dest, dev_addr) == 0 && dp.lastrepeat + 1 == dp.ndigi) mine = 1; /* Also match on any registered callsign from L3/4 */ if (!mine && ax25_listen_mine(&dest, dev) && dp.lastrepeat + 1 == dp.ndigi) mine = 1; /* UI frame - bypass LAPB processing */ if ((*skb->data & ~0x10) == AX25_UI && dp.lastrepeat + 1 == dp.ndigi) { skb_set_transport_header(skb, 2); /* skip control and pid */ ax25_send_to_raw(&dest, skb, skb->data[1]); if (!mine && ax25cmp(&dest, (ax25_address *)dev->broadcast) != 0) { kfree_skb(skb); return 0; } /* Now we are pointing at the pid byte */ switch (skb->data[1]) { case AX25_P_IP: skb_pull(skb,2); /* drop PID/CTRL */ skb_reset_transport_header(skb); skb_reset_network_header(skb); skb->dev = dev; skb->pkt_type = PACKET_HOST; skb->protocol = htons(ETH_P_IP); netif_rx(skb); break; case AX25_P_ARP: skb_pull(skb,2); skb_reset_transport_header(skb); skb_reset_network_header(skb); skb->dev = dev; skb->pkt_type = PACKET_HOST; skb->protocol = htons(ETH_P_ARP); netif_rx(skb); break; case AX25_P_TEXT: /* Now find a suitable dgram socket */ sk = ax25_get_socket(&dest, &src, SOCK_DGRAM); if (sk != NULL) { bh_lock_sock(sk); if (atomic_read(&sk->sk_rmem_alloc) >= sk->sk_rcvbuf) { kfree_skb(skb); } else { /* * Remove the control and PID. */ skb_pull(skb, 2); if (sock_queue_rcv_skb(sk, skb) != 0) kfree_skb(skb); } bh_unlock_sock(sk); sock_put(sk); } else { kfree_skb(skb); } break; default: kfree_skb(skb); /* Will scan SOCK_AX25 RAW sockets */ break; } return 0; } /* * Is connected mode supported on this device ? * If not, should we DM the incoming frame (except DMs) or * silently ignore them. For now we stay quiet. */ if (ax25_dev->values[AX25_VALUES_CONMODE] == 0) { kfree_skb(skb); return 0; } /* LAPB */ /* AX.25 state 1-4 */ ax25_digi_invert(&dp, &reverse_dp); if ((ax25 = ax25_find_cb(&dest, &src, &reverse_dp, dev)) != NULL) { /* * Process the frame. If it is queued up internally it * returns one otherwise we free it immediately. This * routine itself wakes the user context layers so we do * no further work */ if (ax25_process_rx_frame(ax25, skb, type, dama) == 0) kfree_skb(skb); ax25_cb_put(ax25); return 0; } /* AX.25 state 0 (disconnected) */ /* a) received not a SABM(E) */ if ((*skb->data & ~AX25_PF) != AX25_SABM && (*skb->data & ~AX25_PF) != AX25_SABME) { /* * Never reply to a DM. Also ignore any connects for * addresses that are not our interfaces and not a socket. */ if ((*skb->data & ~AX25_PF) != AX25_DM && mine) ax25_return_dm(dev, &src, &dest, &dp); kfree_skb(skb); return 0; } /* b) received SABM(E) */ if (dp.lastrepeat + 1 == dp.ndigi) sk = ax25_find_listener(&dest, 0, dev, SOCK_SEQPACKET); else sk = ax25_find_listener(next_digi, 1, dev, SOCK_SEQPACKET); if (sk != NULL) { bh_lock_sock(sk); if (sk_acceptq_is_full(sk) || (make = ax25_make_new(sk, ax25_dev)) == NULL) { if (mine) ax25_return_dm(dev, &src, &dest, &dp); kfree_skb(skb); bh_unlock_sock(sk); sock_put(sk); return 0; } ax25 = ax25_sk(make); skb_set_owner_r(skb, make); skb_queue_head(&sk->sk_receive_queue, skb); make->sk_state = TCP_ESTABLISHED; sk->sk_ack_backlog++; bh_unlock_sock(sk); } else { if (!mine) { kfree_skb(skb); return 0; } if ((ax25 = ax25_create_cb()) == NULL) { ax25_return_dm(dev, &src, &dest, &dp); kfree_skb(skb); return 0; } ax25_fillin_cb(ax25, ax25_dev); } ax25->source_addr = dest; ax25->dest_addr = src; /* * Sort out any digipeated paths. */ if (dp.ndigi && !ax25->digipeat && (ax25->digipeat = kmalloc(sizeof(ax25_digi), GFP_ATOMIC)) == NULL) { kfree_skb(skb); ax25_destroy_socket(ax25); if (sk) sock_put(sk); return 0; } if (dp.ndigi == 0) { kfree(ax25->digipeat); ax25->digipeat = NULL; } else { /* Reverse the source SABM's path */ memcpy(ax25->digipeat, &reverse_dp, sizeof(ax25_digi)); } if ((*skb->data & ~AX25_PF) == AX25_SABME) { ax25->modulus = AX25_EMODULUS; ax25->window = ax25_dev->values[AX25_VALUES_EWINDOW]; } else { ax25->modulus = AX25_MODULUS; ax25->window = ax25_dev->values[AX25_VALUES_WINDOW]; } ax25_send_control(ax25, AX25_UA, AX25_POLLON, AX25_RESPONSE); #ifdef CONFIG_AX25_DAMA_SLAVE if (dama && ax25->ax25_dev->values[AX25_VALUES_PROTOCOL] == AX25_PROTO_DAMA_SLAVE) ax25_dama_on(ax25); #endif ax25->state = AX25_STATE_3; ax25_cb_add(ax25); ax25_start_heartbeat(ax25); ax25_start_t3timer(ax25); ax25_start_idletimer(ax25); if (sk) { if (!sock_flag(sk, SOCK_DEAD)) sk->sk_data_ready(sk, skb->len); sock_put(sk); } else kfree_skb(skb); return 0; }
int ax25_rebuild_header(struct sk_buff *skb) { struct sk_buff *ourskb; unsigned char *bp = skb->data; ax25_route *route; struct net_device *dev = NULL; ax25_address *src, *dst; ax25_digi *digipeat = NULL; ax25_dev *ax25_dev; ax25_cb *ax25; char ip_mode = ' '; dst = (ax25_address *)(bp + 1); src = (ax25_address *)(bp + 8); if (arp_find(bp + 1, skb)) return 1; route = ax25_get_route(dst, NULL); if (route) { digipeat = route->digipeat; dev = route->dev; ip_mode = route->ip_mode; } if (dev == NULL) dev = skb->dev; if ((ax25_dev = ax25_dev_ax25dev(dev)) == NULL) { goto put; } if (bp[16] == AX25_P_IP) { if (ip_mode == 'V' || (ip_mode == ' ' && ax25_dev->values[AX25_VALUES_IPDEFMODE])) { /* * We copy the buffer and release the original thereby * keeping it straight * * Note: we report 1 back so the caller will * not feed the frame direct to the physical device * We don't want that to happen. (It won't be upset * as we have pulled the frame from the queue by * freeing it). * * NB: TCP modifies buffers that are still * on a device queue, thus we use skb_copy() * instead of using skb_clone() unless this * gets fixed. */ ax25_address src_c; ax25_address dst_c; if ((ourskb = skb_copy(skb, GFP_ATOMIC)) == NULL) { kfree_skb(skb); goto put; } if (skb->sk != NULL) skb_set_owner_w(ourskb, skb->sk); kfree_skb(skb); /* dl9sau: bugfix * after kfree_skb(), dst and src which were pointer * to bp which is part of skb->data would not be valid * anymore hope that after skb_pull(ourskb, ..) our * dsc_c and src_c will not become invalid */ bp = ourskb->data; dst_c = *(ax25_address *)(bp + 1); src_c = *(ax25_address *)(bp + 8); skb_pull(ourskb, AX25_HEADER_LEN - 1); /* Keep PID */ skb_reset_network_header(ourskb); ax25=ax25_send_frame( ourskb, ax25_dev->values[AX25_VALUES_PACLEN], &src_c, &dst_c, digipeat, dev); if (ax25) { ax25_cb_put(ax25); } goto put; } } bp[7] &= ~AX25_CBIT; bp[7] &= ~AX25_EBIT; bp[7] |= AX25_SSSID_SPARE; bp[14] &= ~AX25_CBIT; bp[14] |= AX25_EBIT; bp[14] |= AX25_SSSID_SPARE; skb_pull(skb, AX25_KISS_HEADER_LEN); if (digipeat != NULL) { if ((ourskb = ax25_rt_build_path(skb, src, dst, route->digipeat)) == NULL) { kfree_skb(skb); goto put; } skb = ourskb; } ax25_queue_xmit(skb, dev); put: if (route) ax25_put_route(route); return 1; }
int ax25_rebuild_header(struct sk_buff *skb) { struct sk_buff *ourskb; unsigned char *bp = skb->data; ax25_route *route; struct net_device *dev = NULL; ax25_address *src, *dst; ax25_digi *digipeat = NULL; ax25_dev *ax25_dev; ax25_cb *ax25; char ip_mode = ' '; dst = (ax25_address *)(bp + 1); src = (ax25_address *)(bp + 8); if (arp_find(bp + 1, skb)) return 1; route = ax25_get_route(dst, NULL); if (route) { digipeat = route->digipeat; dev = route->dev; ip_mode = route->ip_mode; } if (dev == NULL) dev = skb->dev; if ((ax25_dev = ax25_dev_ax25dev(dev)) == NULL) { goto put; } if (bp[16] == AX25_P_IP) { if (ip_mode == 'V' || (ip_mode == ' ' && ax25_dev->values[AX25_VALUES_IPDEFMODE])) { ax25_address src_c; ax25_address dst_c; if ((ourskb = skb_copy(skb, GFP_ATOMIC)) == NULL) { kfree_skb(skb); goto put; } if (skb->sk != NULL) skb_set_owner_w(ourskb, skb->sk); kfree_skb(skb); bp = ourskb->data; dst_c = *(ax25_address *)(bp + 1); src_c = *(ax25_address *)(bp + 8); skb_pull(ourskb, AX25_HEADER_LEN - 1); skb_reset_network_header(ourskb); ax25=ax25_send_frame( ourskb, ax25_dev->values[AX25_VALUES_PACLEN], &src_c, &dst_c, digipeat, dev); if (ax25) { ax25_cb_put(ax25); } goto put; } } bp[7] &= ~AX25_CBIT; bp[7] &= ~AX25_EBIT; bp[7] |= AX25_SSSID_SPARE; bp[14] &= ~AX25_CBIT; bp[14] |= AX25_EBIT; bp[14] |= AX25_SSSID_SPARE; skb_pull(skb, AX25_KISS_HEADER_LEN); if (digipeat != NULL) { if ((ourskb = ax25_rt_build_path(skb, src, dst, route->digipeat)) == NULL) { kfree_skb(skb); goto put; } skb = ourskb; } ax25_queue_xmit(skb, dev); put: if (route) ax25_put_route(route); return 1; }