1 #include <u.h>
2 #define NOPLAN9DEFINES
3 #include <libc.h>
4 
5 #include <sys/socket.h>
6 #include <netinet/in.h>
7 #include <sys/un.h>
8 #include <errno.h>
9 
10 #undef sun
11 #define sun sockun
12 extern int _p9dialparse(char*, char**, char**, u32int*, int*);
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, sn;
44 	struct sockaddr_in sa;
45 	struct sockaddr_un sun;
46 
47 	buf = strdup(addr);
48 	if(buf == nil)
49 		return -1;
50 
51 	if(_p9dialparse(buf, &net, &unix, &host, &port) < 0){
52 		free(buf);
53 		return -1;
54 	}
55 	if(strcmp(net, "tcp") == 0)
56 		proto = SOCK_STREAM;
57 	else if(strcmp(net, "udp") == 0)
58 		proto = SOCK_DGRAM;
59 	else if(strcmp(net, "unix") == 0)
60 		goto Unix;
61 	else{
62 		werrstr("can only handle tcp, udp, and unix: not %s", net);
63 		free(buf);
64 		return -1;
65 	}
66 	free(buf);
67 
68 	memset(&sa, 0, sizeof sa);
69 	memmove(&sa.sin_addr, &host, 4);
70 	sa.sin_family = AF_INET;
71 	sa.sin_port = htons(port);
72 	if((s = socket(AF_INET, proto, 0)) < 0)
73 		return -1;
74 	sn = sizeof n;
75 	if(port && getsockopt(s, SOL_SOCKET, SO_TYPE, (char*)&n, &sn) >= 0
76 	&& n == SOCK_STREAM){
77 		n = 1;
78 		setsockopt(s, SOL_SOCKET, SO_REUSEADDR, (char*)&n, sizeof n);
79 	}
80 	if(bind(s, (struct sockaddr*)&sa, sizeof sa) < 0){
81 		close(s);
82 		return -1;
83 	}
84 	if(proto == SOCK_STREAM){
85 		listen(s, 8);
86 		putfd(dir, s);
87 	}
88 	return s;
89 
90 Unix:
91 	memset(&sun, 0, sizeof sun);
92 	sun.sun_family = AF_UNIX;
93 	strcpy(sun.sun_path, unix);
94 	if((s = socket(AF_UNIX, SOCK_STREAM, 0)) < 0)
95 		return -1;
96 	sn = sizeof sun;
97 	if(bind(s, (struct sockaddr*)&sun, sizeof sun) < 0){
98 		if(errno == EADDRINUSE
99 		&& connect(s, (struct sockaddr*)&sun, sizeof sun) < 0
100 		&& errno == ECONNREFUSED){
101 			/* dead socket, so remove it */
102 			remove(unix);
103 			close(s);
104 			if((s = socket(AF_UNIX, SOCK_STREAM, 0)) < 0)
105 				return -1;
106 			if(bind(s, (struct sockaddr*)&sun, sizeof sun) >= 0)
107 				goto Success;
108 		}
109 		close(s);
110 		return -1;
111 	}
112 Success:
113 	listen(s, 8);
114 	putfd(dir, s);
115 	return s;
116 }
117 
118 int
119 p9listen(char *dir, char *newdir)
120 {
121 	int fd;
122 
123 	if((fd = _p9netfd(dir)) < 0){
124 		werrstr("bad 'directory' in listen: %s", dir);
125 		return -1;
126 	}
127 
128 	if((fd = accept(fd, nil, nil)) < 0)
129 		return -1;
130 
131 	putfd(newdir, fd);
132 	return fd;
133 }
134 
135 int
136 p9accept(int cfd, char *dir)
137 {
138 	int fd;
139 
140 	if((fd = _p9netfd(dir)) < 0){
141 		werrstr("bad 'directory' in accept");
142 		return -1;
143 	}
144 	/* need to dup because the listen fd will be closed */
145 	return dup(fd);
146 }
147