1 /*
2 resolver.c: TCP network stuff, for IPv4 and IPv6
3 Oh, and also some URL parsing... extracting host name and such.
4
5 copyright 2008-2010 by the mpg123 project - free software under the terms of the LGPL 2.1
6 see COPYING and AUTHORS files in distribution or http://mpg123.org
7 initially written Thomas Orgis (based on httpget.c)
8
9 The idea is to have everything involving the game between URLs and IPs/connections separated here.
10 I begin with the outsourcing of IPv4 stuff, then make the stuff generic.
11 */
12
13 /* Newer glibc is strict about this: getaddrinfo() stuff needs POSIX2K. */
14 #define _POSIX_C_SOURCE 200112L
15
16 #include "mpg123app.h"
17
18 #ifdef NETWORK
19 #include "true.h"
20 #include "resolver.h"
21 #if !defined (WANT_WIN32_SOCKETS)
22 #include <netdb.h>
23 #include <sys/param.h>
24 #include <sys/socket.h>
25 #include <netinet/in.h>
26 #include <arpa/inet.h>
27 #include <errno.h>
28 #endif
29 #ifdef HAVE_SYS_SELECT_H
30 #include <sys/select.h>
31 #endif
32 #ifdef HAVE_SYS_TIME_H
33 #include <sys/time.h>
34 #endif
35 #ifdef HAVE_SYS_TYPES_H
36 #include <sys/types.h>
37 #endif
38 #include <unistd.h>
39 #include "debug.h"
40
split_url(mpg123_string * url,mpg123_string * auth,mpg123_string * host,mpg123_string * port,mpg123_string * path)41 int split_url(mpg123_string *url, mpg123_string *auth, mpg123_string *host, mpg123_string *port, mpg123_string *path)
42 {
43 size_t pos = 0; /* current position in input URL */
44 size_t pos2 = 0; /* another position in input URL */
45 #ifdef IPV6
46 size_t pos3 = 0; /* yet another (for IPv6 port) */
47 #endif
48 char *part = NULL; /* a part of url we work on */
49 int ret = TRUE; /* return code */
50 /* Zeroing the output strings; not freeing to avoid unnecessary mallocs. */
51 if(auth) auth->fill = 0;
52 if(host) host->fill = 0;
53 if(port) port->fill = 0;
54 if(path) path->fill = 0;
55
56 if(!url || !url->fill || url->p[url->fill-1] != 0)
57 {
58 error("URL string is not good! (Programmer's fault!?)");
59 return FALSE;
60 }
61 if (!(strncmp(url->p+pos, "http://", 7)))
62 pos += 7; /* Drop protocol. */
63
64 /* Extract user[:passwd]@... */
65 if( (part = strchr(url->p+pos,'@')) )
66 {
67 size_t i;
68 size_t partlen = part - url->p - pos;
69 int have_auth = TRUE;
70 /* User names or passwords don't have "/" in them (?), the "@" wasn't for real if we find such. */
71 for(i=0;i<partlen;i++)
72 {
73 if(url->p[pos+i] == '/' )
74 {
75 have_auth = FALSE;
76 break;
77 }
78 }
79 if(have_auth)
80 {
81 if(auth != NULL && !mpg123_set_substring(auth, url->p, pos, partlen))
82 {
83 error("Cannot set auth string (out of mem?).");
84 return FALSE;
85 }
86 pos += partlen+1; /* Continuing after the "@". */
87 }
88 }
89
90 /* Extract host name or IP. */
91 #ifdef IPV6
92 if(url->p[pos] == '[')
93 { /* It's possibly an IPv6 url in [ ] */
94 ++pos;
95 if( (part = strchr(url->p+pos,']')) != NULL)
96 {
97 pos2 = part-url->p;
98 pos3 = pos2+1; /* : after ] */
99 }
100 else { error("Malformed IPv6 URL!"); return FALSE; }
101 }
102 else
103 {
104 #endif
105 for(pos2=pos; pos2 < url->fill-1; ++pos2)
106 {
107 char a = url->p[pos2];
108 if( a == ':' || a == '/') break;
109 }
110 #ifdef IPV6
111 pos3 = pos2;
112 }
113 #endif
114 /* At pos2 there is now either a delimiter or the end. */
115 debug4("hostname between %lu and %lu, %lu chars of %s", (unsigned long)pos, (unsigned long)pos2, (unsigned long)(pos2-pos), url->p + pos);
116 if(host != NULL && !mpg123_set_substring(host, url->p, pos, pos2-pos))
117 {
118 error("Cannot set host string (out of mem?).");
119 return FALSE;
120 }
121 #ifdef IPV6
122 pos = pos3; /* Look after ], if present. */
123 #else
124 pos = pos2;
125 #endif
126
127 /* Now for the port... */
128 if(url->p[pos] == ':')
129 {
130 pos += 1; /* We begin _after_ the ":". */
131 for(pos2=pos; pos2 < url->fill-1; ++pos2)
132 if( url->p[pos2] == '/' ) break;
133
134 /* Check for port being numbers? Not sure if that's needed. */
135 if(port) ret = mpg123_set_substring(port, url->p, pos, pos2-pos);
136 pos = pos2;
137 }
138 else if(port) ret = mpg123_set_string(port, "80");
139
140 if(!ret)
141 {
142 error("Cannot set port string (out of mem?).");
143 return FALSE;
144 }
145
146 /* Now only the path is left.
147 If there is no path at all, assume "/" */
148 if(path) ret = url->p[pos] == 0
149 ? mpg123_set_string(path, "/")
150 : mpg123_set_substring(path, url->p, pos, url->fill-1-pos);
151
152 if(!ret) error("Cannot set path string (out of mem?)");
153
154 return ret;
155 }
156
157 /* Switch between blocking and non-blocking mode. */
158 #if !defined (WANT_WIN32_SOCKETS)
nonblock(int sock)159 static void nonblock(int sock)
160 {
161 int flags = fcntl(sock, F_GETFL);
162 flags |= O_NONBLOCK;
163 fcntl(sock, F_SETFL, flags);
164 }
165
block(int sock)166 static void block(int sock)
167 {
168 int flags = fcntl(sock, F_GETFL);
169 flags &= ~O_NONBLOCK;
170 fcntl(sock, F_SETFL, flags);
171 }
172
173 /* If we want a timeout, connect non-blocking and wait for that long... */
timeout_connect(int sockfd,const struct sockaddr * serv_addr,socklen_t addrlen)174 static int timeout_connect(int sockfd, const struct sockaddr *serv_addr, socklen_t addrlen)
175 {
176 if(param.timeout > 0)
177 {
178 int err;
179 nonblock(sockfd);
180 err = connect(sockfd, serv_addr, addrlen);
181 if(err == 0)
182 {
183 debug("immediately successful");
184 block(sockfd);
185 return 0;
186 }
187 else if(errno == EINPROGRESS)
188 {
189 struct timeval tv;
190 fd_set fds;
191 tv.tv_sec = param.timeout;
192 tv.tv_usec = 0;
193
194 debug("in progress, waiting...");
195
196 FD_ZERO(&fds);
197 FD_SET(sockfd, &fds);
198 err = select(sockfd+1, NULL, &fds, NULL, &tv);
199 if(err > 0)
200 {
201 socklen_t len = sizeof(err);
202 if( (getsockopt(sockfd, SOL_SOCKET, SO_ERROR, &err, &len) == 0)
203 && (err == 0) )
204 {
205 debug("non-blocking connect has been successful");
206 block(sockfd);
207 return 0;
208 }
209 else
210 {
211 error1("connection error: %s", strerror(err));
212 return -1;
213 }
214 }
215 else if(err == 0)
216 {
217 error("connection timed out");
218 return -1;
219 }
220 else
221 {
222 error1("error from select(): %s", strerror(errno));
223 return -1;
224 }
225 }
226 else
227 {
228 error1("connection failed: %s", strerror(errno));
229 return err;
230 }
231 }
232 else
233 {
234 if(connect(sockfd, serv_addr, addrlen))
235 {
236 error1("connection failed: %s", strerror(errno));
237 return -1;
238 }
239 else return 0; /* _good_ */
240 }
241 }
242
243
244 /* So, this then is the only routine that should know about IPv4 or v6 in future. */
open_connection(mpg123_string * host,mpg123_string * port)245 int open_connection(mpg123_string *host, mpg123_string *port)
246 {
247 #ifndef IPV6 /* The legacy code for IPv4. No real change to keep all compatibility. */
248 #ifndef INADDR_NONE
249 #define INADDR_NONE 0xffffffff
250 #endif
251 struct sockaddr_in server;
252 struct hostent *myhostent;
253 struct in_addr myaddr;
254 int isip = 1;
255 char *cptr = host->p;
256 int sock = -1;
257 if(param.verbose>1) fprintf(stderr, "Note: Attempting old-style connection to %s\n", host->p);
258 /* Resolve to IP; parse port number. */
259 while(*cptr) /* Iterate over characters of hostname, check if it's an IP or name. */
260 {
261 if ((*cptr < '0' || *cptr > '9') && *cptr != '.')
262 {
263 isip = 0;
264 break;
265 }
266 cptr++;
267 }
268 if(!isip)
269 { /* Name lookup. */
270 if (!(myhostent = gethostbyname(host->p))) return -1;
271
272 memcpy (&myaddr, myhostent->h_addr, sizeof(myaddr));
273 server.sin_addr.s_addr = myaddr.s_addr;
274 }
275 else /* Just use the IP. */
276 if((server.sin_addr.s_addr = inet_addr(host->p)) == INADDR_NONE)
277 return -1;
278
279 server.sin_port = htons(atoi(port->p));
280 server.sin_family = AF_INET;
281
282 if((sock = socket(PF_INET, SOCK_STREAM, 6)) < 0)
283 {
284 error1("Cannot create socket: %s", strerror(errno));
285 return -1;
286 }
287 if(timeout_connect(sock, (struct sockaddr *)&server, sizeof(server)))
288 return -1;
289 #else /* Host lookup and connection in a protocol independent manner. */
290 struct addrinfo hints;
291 struct addrinfo *addr, *addrlist;
292 int ret, sock = -1;
293
294 if(param.verbose>1) fprintf(stderr, "Note: Attempting new-style connection to %s\n", host->p);
295 memset(&hints, 0, sizeof(struct addrinfo));
296 hints.ai_family = AF_UNSPEC; /* We accept both IPv4 and IPv6 ... and perhaps IPv8;-) */
297 hints.ai_socktype = SOCK_STREAM;
298 hints.ai_flags = 0;
299 #ifdef HAVE_GAI_ADDRCONFIG
300 hints.ai_flags |= AI_ADDRCONFIG; /* Only ask for addresses that we have configured interfaces for. */
301 #endif
302 ret = getaddrinfo(host->p, port->p, &hints, &addrlist);
303 if(ret != 0)
304 {
305 error3("Resolving %s:%s: %s", host->p, port->p, gai_strerror(ret));
306 return -1;
307 }
308
309 addr = addrlist;
310 while(addr != NULL)
311 {
312 sock = socket(addr->ai_family, addr->ai_socktype, addr->ai_protocol);
313 if(sock >= 0)
314 {
315 if(timeout_connect(sock, addr->ai_addr, addr->ai_addrlen) == 0)
316 break;
317
318 close(sock);
319 sock=-1;
320 }
321 addr=addr->ai_next;
322 }
323 if(sock < 0) error2("Cannot resolve/connect to %s:%s!", host->p, port->p);
324
325 freeaddrinfo(addrlist);
326 #endif
327 return sock; /* Hopefully, that's an open socket to talk with. */
328 }
329 #endif /* !defined (WANT_WIN32_SOCKETS) */
330 #else /* NETWORK */
331
resolver_dummy_without_sense()332 void resolver_dummy_without_sense()
333 {
334 /* Some compilers don't like empty source files. */
335 }
336
337 #endif
338