1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * |
4 | * Copyright Jonathan Naylor G4KLX (g4klx@g4klx.demon.co.uk) |
5 | */ |
6 | #include <linux/module.h> |
7 | #include <linux/proc_fs.h> |
8 | #include <linux/kernel.h> |
9 | #include <linux/interrupt.h> |
10 | #include <linux/fs.h> |
11 | #include <linux/types.h> |
12 | #include <linux/sysctl.h> |
13 | #include <linux/string.h> |
14 | #include <linux/socket.h> |
15 | #include <linux/errno.h> |
16 | #include <linux/fcntl.h> |
17 | #include <linux/in.h> |
18 | #include <linux/if_ether.h> /* For the statistics structure. */ |
19 | #include <linux/slab.h> |
20 | #include <linux/uaccess.h> |
21 | |
22 | #include <asm/io.h> |
23 | |
24 | #include <linux/inet.h> |
25 | #include <linux/netdevice.h> |
26 | #include <linux/etherdevice.h> |
27 | #include <linux/if_arp.h> |
28 | #include <linux/skbuff.h> |
29 | |
30 | #include <net/ip.h> |
31 | #include <net/arp.h> |
32 | |
33 | #include <net/ax25.h> |
34 | #include <net/netrom.h> |
35 | |
36 | /* |
37 | * Only allow IP over NET/ROM frames through if the netrom device is up. |
38 | */ |
39 | |
40 | int nr_rx_ip(struct sk_buff *skb, struct net_device *dev) |
41 | { |
42 | struct net_device_stats *stats = &dev->stats; |
43 | |
44 | if (!netif_running(dev)) { |
45 | stats->rx_dropped++; |
46 | return 0; |
47 | } |
48 | |
49 | stats->rx_packets++; |
50 | stats->rx_bytes += skb->len; |
51 | |
52 | skb->protocol = htons(ETH_P_IP); |
53 | |
54 | /* Spoof incoming device */ |
55 | skb->dev = dev; |
56 | skb->mac_header = skb->network_header; |
57 | skb_reset_network_header(skb); |
58 | skb->pkt_type = PACKET_HOST; |
59 | |
60 | netif_rx(skb); |
61 | |
62 | return 1; |
63 | } |
64 | |
65 | static int (struct sk_buff *skb, struct net_device *dev, |
66 | unsigned short type, |
67 | const void *daddr, const void *saddr, unsigned int len) |
68 | { |
69 | unsigned char *buff = skb_push(skb, NR_NETWORK_LEN + NR_TRANSPORT_LEN); |
70 | |
71 | memcpy(buff, (saddr != NULL) ? saddr : dev->dev_addr, dev->addr_len); |
72 | buff[6] &= ~AX25_CBIT; |
73 | buff[6] &= ~AX25_EBIT; |
74 | buff[6] |= AX25_SSSID_SPARE; |
75 | buff += AX25_ADDR_LEN; |
76 | |
77 | if (daddr != NULL) |
78 | memcpy(buff, daddr, dev->addr_len); |
79 | buff[6] &= ~AX25_CBIT; |
80 | buff[6] |= AX25_EBIT; |
81 | buff[6] |= AX25_SSSID_SPARE; |
82 | buff += AX25_ADDR_LEN; |
83 | |
84 | *buff++ = sysctl_netrom_network_ttl_initialiser; |
85 | |
86 | *buff++ = NR_PROTO_IP; |
87 | *buff++ = NR_PROTO_IP; |
88 | *buff++ = 0; |
89 | *buff++ = 0; |
90 | *buff++ = NR_PROTOEXT; |
91 | |
92 | if (daddr != NULL) |
93 | return 37; |
94 | |
95 | return -37; |
96 | } |
97 | |
98 | static int __must_check nr_set_mac_address(struct net_device *dev, void *addr) |
99 | { |
100 | struct sockaddr *sa = addr; |
101 | int err; |
102 | |
103 | if (!memcmp(p: dev->dev_addr, q: sa->sa_data, size: dev->addr_len)) |
104 | return 0; |
105 | |
106 | if (dev->flags & IFF_UP) { |
107 | err = ax25_listen_register((ax25_address *)sa->sa_data, NULL); |
108 | if (err) |
109 | return err; |
110 | |
111 | ax25_listen_release((const ax25_address *)dev->dev_addr, NULL); |
112 | } |
113 | |
114 | dev_addr_set(dev, addr: sa->sa_data); |
115 | |
116 | return 0; |
117 | } |
118 | |
119 | static int nr_open(struct net_device *dev) |
120 | { |
121 | int err; |
122 | |
123 | err = ax25_listen_register((const ax25_address *)dev->dev_addr, NULL); |
124 | if (err) |
125 | return err; |
126 | |
127 | netif_start_queue(dev); |
128 | |
129 | return 0; |
130 | } |
131 | |
132 | static int nr_close(struct net_device *dev) |
133 | { |
134 | ax25_listen_release((const ax25_address *)dev->dev_addr, NULL); |
135 | netif_stop_queue(dev); |
136 | return 0; |
137 | } |
138 | |
139 | static netdev_tx_t nr_xmit(struct sk_buff *skb, struct net_device *dev) |
140 | { |
141 | struct net_device_stats *stats = &dev->stats; |
142 | unsigned int len = skb->len; |
143 | |
144 | if (!nr_route_frame(skb, NULL)) { |
145 | kfree_skb(skb); |
146 | stats->tx_errors++; |
147 | return NETDEV_TX_OK; |
148 | } |
149 | |
150 | stats->tx_packets++; |
151 | stats->tx_bytes += len; |
152 | |
153 | return NETDEV_TX_OK; |
154 | } |
155 | |
156 | static const struct header_ops = { |
157 | .create = nr_header, |
158 | }; |
159 | |
160 | static const struct net_device_ops nr_netdev_ops = { |
161 | .ndo_open = nr_open, |
162 | .ndo_stop = nr_close, |
163 | .ndo_start_xmit = nr_xmit, |
164 | .ndo_set_mac_address = nr_set_mac_address, |
165 | }; |
166 | |
167 | void nr_setup(struct net_device *dev) |
168 | { |
169 | dev->mtu = NR_MAX_PACKET_SIZE; |
170 | dev->netdev_ops = &nr_netdev_ops; |
171 | dev->header_ops = &nr_header_ops; |
172 | dev->hard_header_len = NR_NETWORK_LEN + NR_TRANSPORT_LEN; |
173 | dev->addr_len = AX25_ADDR_LEN; |
174 | dev->type = ARPHRD_NETROM; |
175 | |
176 | /* New-style flags. */ |
177 | dev->flags = IFF_NOARP; |
178 | } |
179 | |