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 
35 int
36 p9announce(char *addr, char *dir)
37 {
38 	int proto;
39 	char *buf, *unix;
40 	char *net;
41 	u32int host;
42 	int port, s;
43 	int n;
44 	socklen_t sn;
45 	struct sockaddr_in sa;
46 	struct sockaddr_un sun;
47 
48 	buf = strdup(addr);
49 	if(buf == nil)
50 		return -1;
51 
52 	if(p9dialparse(buf, &net, &unix, &host, &port) < 0){
53 		free(buf);
54 		return -1;
55 	}
56 	if(strcmp(net, "tcp") == 0)
57 		proto = SOCK_STREAM;
58 	else if(strcmp(net, "udp") == 0)
59 		proto = SOCK_DGRAM;
60 	else if(strcmp(net, "unix") == 0)
61 		goto Unix;
62 	else{
63 		werrstr("can only handle tcp, udp, and unix: not %s", net);
64 		free(buf);
65 		return -1;
66 	}
67 	free(buf);
68 
69 	memset(&sa, 0, sizeof sa);
70 	memmove(&sa.sin_addr, &host, 4);
71 	sa.sin_family = AF_INET;
72 	sa.sin_port = htons(port);
73 	if((s = socket(AF_INET, proto, 0)) < 0)
74 		return -1;
75 	sn = sizeof n;
76 	if(port && getsockopt(s, SOL_SOCKET, SO_TYPE, (void*)&n, &sn) >= 0
77 	&& n == SOCK_STREAM){
78 		n = 1;
79 		setsockopt(s, SOL_SOCKET, SO_REUSEADDR, (char*)&n, sizeof n);
80 	}
81 	if(bind(s, (struct sockaddr*)&sa, sizeof sa) < 0){
82 		close(s);
83 		return -1;
84 	}
85 	if(proto == SOCK_STREAM){
86 		listen(s, 8);
87 		putfd(dir, s);
88 	}
89 	return s;
90 
91 Unix:
92 	memset(&sun, 0, sizeof sun);
93 	sun.sun_family = AF_UNIX;
94 	strcpy(sun.sun_path, unix);
95 	if((s = socket(AF_UNIX, SOCK_STREAM, 0)) < 0)
96 		return -1;
97 	sn = sizeof sun;
98 	if(bind(s, (struct sockaddr*)&sun, sizeof sun) < 0){
99 		if(errno == EADDRINUSE
100 		&& connect(s, (struct sockaddr*)&sun, sizeof sun) < 0
101 		&& errno == ECONNREFUSED){
102 			/* dead socket, so remove it */
103 			remove(unix);
104 			close(s);
105 			if((s = socket(AF_UNIX, SOCK_STREAM, 0)) < 0)
106 				return -1;
107 			if(bind(s, (struct sockaddr*)&sun, sizeof sun) >= 0)
108 				goto Success;
109 		}
110 		close(s);
111 		return -1;
112 	}
113 Success:
114 	listen(s, 8);
115 	putfd(dir, s);
116 	return s;
117 }
118 
119 int
120 p9listen(char *dir, char *newdir)
121 {
122 	int fd, one;
123 
124 	if((fd = _p9netfd(dir)) < 0){
125 		werrstr("bad 'directory' in listen: %s", dir);
126 		return -1;
127 	}
128 
129 	if((fd = accept(fd, nil, nil)) < 0)
130 		return -1;
131 
132 	one = 1;
133 	setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, (char*)&one, sizeof one);
134 
135 	putfd(newdir, fd);
136 	return fd;
137 }
138 
139 int
140 p9accept(int cfd, char *dir)
141 {
142 	int fd;
143 
144 	if((fd = _p9netfd(dir)) < 0){
145 		werrstr("bad 'directory' in accept");
146 		return -1;
147 	}
148 	/* need to dup because the listen fd will be closed */
149 	return dup(fd);
150 }
151