1 #include <u.h>
2 #define NOPLAN9DEFINES
3 #include <libc.h>
4 
5 #include <sys/socket.h>
6 #include <netinet/in.h>
7 #include <netinet/tcp.h>
8 #include <sys/un.h>
9 #include <errno.h>
10 
11 #undef sun
12 #define sun sockun
13 
14 int
15 _p9netfd(char *dir)
16 {
17 	int fd;
18 
19 	if(strncmp(dir, "/dev/fd/", 8) != 0)
20 		return -1;
21 	fd = strtol(dir+8, &dir, 0);
22 	if(*dir != 0)
23 		return -1;
24 	return fd;
25 }
26 
27 static void
28 putfd(char *dir, int fd)
29 {
30 	snprint(dir, NETPATHLEN, "/dev/fd/%d", fd);
31 }
32 
33 #undef unix
34 #define unix sockunix
35 
36 static int
37 addrlen(struct sockaddr_storage *ss)
38 {
39 	switch(ss->ss_family){
40 	case AF_INET:
41 		return sizeof(struct sockaddr_in);
42 	case AF_INET6:
43 		return sizeof(struct sockaddr_in6);
44 	case AF_UNIX:
45 		return sizeof(struct sockaddr_un);
46 	}
47 	return 0;
48 }
49 
50 int
51 p9announce(char *addr, char *dir)
52 {
53 	int proto;
54 	char *buf, *unix;
55 	char *net;
56 	int port, s;
57 	int n;
58 	socklen_t sn;
59 	struct sockaddr_storage ss;
60 
61 	buf = strdup(addr);
62 	if(buf == nil)
63 		return -1;
64 
65 	if(p9dialparse(buf, &net, &unix, &ss, &port) < 0){
66 		free(buf);
67 		return -1;
68 	}
69 	if(strcmp(net, "tcp") == 0)
70 		proto = SOCK_STREAM;
71 	else if(strcmp(net, "udp") == 0)
72 		proto = SOCK_DGRAM;
73 	else if(strcmp(net, "unix") == 0)
74 		goto Unix;
75 	else{
76 		werrstr("can only handle tcp, udp, and unix: not %s", net);
77 		free(buf);
78 		return -1;
79 	}
80 	free(buf);
81 
82 	if((s = socket(ss.ss_family, proto, 0)) < 0)
83 		return -1;
84 	sn = sizeof n;
85 	if(port && getsockopt(s, SOL_SOCKET, SO_TYPE, (void*)&n, &sn) >= 0
86 	&& n == SOCK_STREAM){
87 		n = 1;
88 		setsockopt(s, SOL_SOCKET, SO_REUSEADDR, (char*)&n, sizeof n);
89 	}
90 	if(bind(s, (struct sockaddr*)&ss, addrlen(&ss)) < 0){
91 		close(s);
92 		return -1;
93 	}
94 	if(proto == SOCK_STREAM){
95 		listen(s, 8);
96 		putfd(dir, s);
97 	}
98 	return s;
99 
100 Unix:
101 	if((s = socket(ss.ss_family, SOCK_STREAM, 0)) < 0)
102 		return -1;
103 	if(bind(s, (struct sockaddr*)&ss, addrlen(&ss)) < 0){
104 		if(errno == EADDRINUSE
105 		&& connect(s, (struct sockaddr*)&ss, addrlen(&ss)) < 0
106 		&& errno == ECONNREFUSED){
107 			/* dead socket, so remove it */
108 			remove(unix);
109 			close(s);
110 			if((s = socket(ss.ss_family, SOCK_STREAM, 0)) < 0)
111 				return -1;
112 			if(bind(s, (struct sockaddr*)&ss, addrlen(&ss)) >= 0)
113 				goto Success;
114 		}
115 		close(s);
116 		return -1;
117 	}
118 Success:
119 	listen(s, 8);
120 	putfd(dir, s);
121 	return s;
122 }
123 
124 int
125 p9listen(char *dir, char *newdir)
126 {
127 	int fd, one;
128 
129 	if((fd = _p9netfd(dir)) < 0){
130 		werrstr("bad 'directory' in listen: %s", dir);
131 		return -1;
132 	}
133 
134 	if((fd = accept(fd, nil, nil)) < 0)
135 		return -1;
136 
137 	one = 1;
138 	setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, (char*)&one, sizeof one);
139 
140 	putfd(newdir, fd);
141 	return fd;
142 }
143 
144 int
145 p9accept(int cfd, char *dir)
146 {
147 	int fd;
148 
149 	if((fd = _p9netfd(dir)) < 0){
150 		werrstr("bad 'directory' in accept");
151 		return -1;
152 	}
153 	/* need to dup because the listen fd will be closed */
154 	return dup(fd);
155 }