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 int
37 p9announce(char *addr, char *dir)
38 {
39 	int proto;
40 	char *buf, *unix;
41 	char *net;
42 	u32int host;
43 	int port, s;
44 	int n;
45 	socklen_t sn;
46 	struct sockaddr_in sa;
47 	struct sockaddr_un sun;
48 
49 	buf = strdup(addr);
50 	if(buf == nil)
51 		return -1;
52 
53 	if(p9dialparse(buf, &net, &unix, &host, &port) < 0){
54 		free(buf);
55 		return -1;
56 	}
57 	if(strcmp(net, "tcp") == 0)
58 		proto = SOCK_STREAM;
59 	else if(strcmp(net, "udp") == 0)
60 		proto = SOCK_DGRAM;
61 	else if(strcmp(net, "unix") == 0)
62 		goto Unix;
63 	else{
64 		werrstr("can only handle tcp, udp, and unix: not %s", net);
65 		free(buf);
66 		return -1;
67 	}
68 	free(buf);
69 
70 	memset(&sa, 0, sizeof sa);
71 	memmove(&sa.sin_addr, &host, 4);
72 	sa.sin_family = AF_INET;
73 	sa.sin_port = htons(port);
74 	if((s = socket(AF_INET, proto, 0)) < 0)
75 		return -1;
76 	sn = sizeof n;
77 	if(port && getsockopt(s, SOL_SOCKET, SO_TYPE, (void*)&n, &sn) >= 0
78 	&& n == SOCK_STREAM){
79 		n = 1;
80 		setsockopt(s, SOL_SOCKET, SO_REUSEADDR, (char*)&n, sizeof n);
81 	}
82 	if(bind(s, (struct sockaddr*)&sa, sizeof sa) < 0){
83 		close(s);
84 		return -1;
85 	}
86 	if(proto == SOCK_STREAM){
87 		listen(s, 8);
88 		putfd(dir, s);
89 	}
90 	return s;
91 
92 Unix:
93 	memset(&sun, 0, sizeof sun);
94 	sun.sun_family = AF_UNIX;
95 	strcpy(sun.sun_path, unix);
96 	if((s = socket(AF_UNIX, SOCK_STREAM, 0)) < 0)
97 		return -1;
98 	sn = sizeof sun;
99 	if(bind(s, (struct sockaddr*)&sun, sizeof sun) < 0){
100 		if(errno == EADDRINUSE
101 		&& connect(s, (struct sockaddr*)&sun, sizeof sun) < 0
102 		&& errno == ECONNREFUSED){
103 			/* dead socket, so remove it */
104 			remove(unix);
105 			close(s);
106 			if((s = socket(AF_UNIX, SOCK_STREAM, 0)) < 0)
107 				return -1;
108 			if(bind(s, (struct sockaddr*)&sun, sizeof sun) >= 0)
109 				goto Success;
110 		}
111 		close(s);
112 		return -1;
113 	}
114 Success:
115 	listen(s, 8);
116 	putfd(dir, s);
117 	return s;
118 }
119 
120 int
121 p9listen(char *dir, char *newdir)
122 {
123 	int fd, one;
124 
125 	if((fd = _p9netfd(dir)) < 0){
126 		werrstr("bad 'directory' in listen: %s", dir);
127 		return -1;
128 	}
129 
130 	if((fd = accept(fd, nil, nil)) < 0)
131 		return -1;
132 
133 	one = 1;
134 	setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, (char*)&one, sizeof one);
135 
136 	putfd(newdir, fd);
137 	return fd;
138 }
139 
140 int
141 p9accept(int cfd, char *dir)
142 {
143 	int fd;
144 
145 	if((fd = _p9netfd(dir)) < 0){
146 		werrstr("bad 'directory' in accept");
147 		return -1;
148 	}
149 	/* need to dup because the listen fd will be closed */
150 	return dup(fd);
151 }
152