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15#include <unistd.h>
16#include <errno.h>
17#include <netinet/in.h>
18#include "kern_constants.h"
19#include "umcast.h"
20#include "net_user.h"
21#include "um_malloc.h"
22#include "user.h"
23
24static struct sockaddr_in *new_addr(char *addr, unsigned short port)
25{
26 struct sockaddr_in *sin;
27
28 sin = uml_kmalloc(sizeof(struct sockaddr_in), UM_GFP_KERNEL);
29 if (sin == NULL) {
30 printk(UM_KERN_ERR "new_addr: allocation of sockaddr_in "
31 "failed\n");
32 return NULL;
33 }
34 sin->sin_family = AF_INET;
35 if (addr)
36 sin->sin_addr.s_addr = in_aton(addr);
37 else
38 sin->sin_addr.s_addr = INADDR_ANY;
39 sin->sin_port = htons(port);
40 return sin;
41}
42
43static int umcast_user_init(void *data, void *dev)
44{
45 struct umcast_data *pri = data;
46
47 pri->remote_addr = new_addr(pri->addr, pri->rport);
48 if (pri->unicast)
49 pri->listen_addr = new_addr(NULL, pri->lport);
50 else
51 pri->listen_addr = pri->remote_addr;
52 pri->dev = dev;
53 return 0;
54}
55
56static void umcast_remove(void *data)
57{
58 struct umcast_data *pri = data;
59
60 kfree(pri->listen_addr);
61 if (pri->unicast)
62 kfree(pri->remote_addr);
63 pri->listen_addr = pri->remote_addr = NULL;
64}
65
66static int umcast_open(void *data)
67{
68 struct umcast_data *pri = data;
69 struct sockaddr_in *lsin = pri->listen_addr;
70 struct sockaddr_in *rsin = pri->remote_addr;
71 struct ip_mreq mreq;
72 int fd, yes = 1, err = -EINVAL;
73
74
75 if ((!pri->unicast && lsin->sin_addr.s_addr == 0) ||
76 (rsin->sin_addr.s_addr == 0) ||
77 (lsin->sin_port == 0) || (rsin->sin_port == 0))
78 goto out;
79
80 fd = socket(AF_INET, SOCK_DGRAM, 0);
81
82 if (fd < 0) {
83 err = -errno;
84 printk(UM_KERN_ERR "umcast_open : data socket failed, "
85 "errno = %d\n", errno);
86 goto out;
87 }
88
89 if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(yes)) < 0) {
90 err = -errno;
91 printk(UM_KERN_ERR "umcast_open: SO_REUSEADDR failed, "
92 "errno = %d\n", errno);
93 goto out_close;
94 }
95
96 if (!pri->unicast) {
97
98 if (setsockopt(fd, SOL_IP, IP_MULTICAST_TTL, &pri->ttl,
99 sizeof(pri->ttl)) < 0) {
100 err = -errno;
101 printk(UM_KERN_ERR "umcast_open: IP_MULTICAST_TTL "
102 "failed, error = %d\n", errno);
103 goto out_close;
104 }
105
106
107 if (setsockopt(fd, SOL_IP, IP_MULTICAST_LOOP,
108 &yes, sizeof(yes)) < 0) {
109 err = -errno;
110 printk(UM_KERN_ERR "umcast_open: IP_MULTICAST_LOOP "
111 "failed, error = %d\n", errno);
112 goto out_close;
113 }
114 }
115
116
117 if (bind(fd, (struct sockaddr *) lsin, sizeof(*lsin)) < 0) {
118 err = -errno;
119 printk(UM_KERN_ERR "umcast_open : data bind failed, "
120 "errno = %d\n", errno);
121 goto out_close;
122 }
123
124 if (!pri->unicast) {
125
126 mreq.imr_multiaddr.s_addr = lsin->sin_addr.s_addr;
127 mreq.imr_interface.s_addr = 0;
128 if (setsockopt(fd, SOL_IP, IP_ADD_MEMBERSHIP,
129 &mreq, sizeof(mreq)) < 0) {
130 err = -errno;
131 printk(UM_KERN_ERR "umcast_open: IP_ADD_MEMBERSHIP "
132 "failed, error = %d\n", errno);
133 printk(UM_KERN_ERR "There appears not to be a "
134 "multicast-capable network interface on the "
135 "host.\n");
136 printk(UM_KERN_ERR "eth0 should be configured in order "
137 "to use the multicast transport.\n");
138 goto out_close;
139 }
140 }
141
142 return fd;
143
144 out_close:
145 close(fd);
146 out:
147 return err;
148}
149
150static void umcast_close(int fd, void *data)
151{
152 struct umcast_data *pri = data;
153
154 if (!pri->unicast) {
155 struct ip_mreq mreq;
156 struct sockaddr_in *lsin = pri->listen_addr;
157
158 mreq.imr_multiaddr.s_addr = lsin->sin_addr.s_addr;
159 mreq.imr_interface.s_addr = 0;
160 if (setsockopt(fd, SOL_IP, IP_DROP_MEMBERSHIP,
161 &mreq, sizeof(mreq)) < 0) {
162 printk(UM_KERN_ERR "umcast_close: IP_DROP_MEMBERSHIP "
163 "failed, error = %d\n", errno);
164 }
165 }
166
167 close(fd);
168}
169
170int umcast_user_write(int fd, void *buf, int len, struct umcast_data *pri)
171{
172 struct sockaddr_in *data_addr = pri->remote_addr;
173
174 return net_sendto(fd, buf, len, data_addr, sizeof(*data_addr));
175}
176
177const struct net_user_info umcast_user_info = {
178 .init = umcast_user_init,
179 .open = umcast_open,
180 .close = umcast_close,
181 .remove = umcast_remove,
182 .add_address = NULL,
183 .delete_address = NULL,
184 .mtu = ETH_MAX_PACKET,
185 .max_packet = ETH_MAX_PACKET + ETH_HEADER_OTHER,
186};
187
