xref: /illumos-kvm-cmd/slirp/misc.c (revision 68396ea9)
1 /*
2  * Copyright (c) 1995 Danny Gasparovski.
3  *
4  * Please read the file COPYRIGHT for the
5  * terms and conditions of the copyright.
6  */
7 
8 #include <slirp.h>
9 #include <libslirp.h>
10 
11 #include "monitor.h"
12 
13 #ifdef DEBUG
14 int slirp_debug = DBG_CALL|DBG_MISC|DBG_ERROR;
15 #endif
16 
17 struct quehead {
18 	struct quehead *qh_link;
19 	struct quehead *qh_rlink;
20 };
21 
22 inline void
insque(void * a,void * b)23 insque(void *a, void *b)
24 {
25 	register struct quehead *element = (struct quehead *) a;
26 	register struct quehead *head = (struct quehead *) b;
27 	element->qh_link = head->qh_link;
28 	head->qh_link = (struct quehead *)element;
29 	element->qh_rlink = (struct quehead *)head;
30 	((struct quehead *)(element->qh_link))->qh_rlink
31 	= (struct quehead *)element;
32 }
33 
34 inline void
remque(void * a)35 remque(void *a)
36 {
37   register struct quehead *element = (struct quehead *) a;
38   ((struct quehead *)(element->qh_link))->qh_rlink = element->qh_rlink;
39   ((struct quehead *)(element->qh_rlink))->qh_link = element->qh_link;
40   element->qh_rlink = NULL;
41 }
42 
add_exec(struct ex_list ** ex_ptr,int do_pty,char * exec,struct in_addr addr,int port)43 int add_exec(struct ex_list **ex_ptr, int do_pty, char *exec,
44              struct in_addr addr, int port)
45 {
46 	struct ex_list *tmp_ptr;
47 
48 	/* First, check if the port is "bound" */
49 	for (tmp_ptr = *ex_ptr; tmp_ptr; tmp_ptr = tmp_ptr->ex_next) {
50 		if (port == tmp_ptr->ex_fport &&
51 		    addr.s_addr == tmp_ptr->ex_addr.s_addr)
52 			return -1;
53 	}
54 
55 	tmp_ptr = *ex_ptr;
56 	*ex_ptr = (struct ex_list *)malloc(sizeof(struct ex_list));
57 	(*ex_ptr)->ex_fport = port;
58 	(*ex_ptr)->ex_addr = addr;
59 	(*ex_ptr)->ex_pty = do_pty;
60 	(*ex_ptr)->ex_exec = (do_pty == 3) ? exec : strdup(exec);
61 	(*ex_ptr)->ex_next = tmp_ptr;
62 	return 0;
63 }
64 
65 #ifndef HAVE_STRERROR
66 
67 /*
68  * For systems with no strerror
69  */
70 
71 extern int sys_nerr;
72 extern char *sys_errlist[];
73 
74 char *
strerror(error)75 strerror(error)
76 	int error;
77 {
78 	if (error < sys_nerr)
79 	   return sys_errlist[error];
80 	else
81 	   return "Unknown error.";
82 }
83 
84 #endif
85 
86 
87 #ifdef _WIN32
88 
89 int
fork_exec(struct socket * so,const char * ex,int do_pty)90 fork_exec(struct socket *so, const char *ex, int do_pty)
91 {
92     /* not implemented */
93     return 0;
94 }
95 
96 #else
97 
98 /*
99  * XXX This is ugly
100  * We create and bind a socket, then fork off to another
101  * process, which connects to this socket, after which we
102  * exec the wanted program.  If something (strange) happens,
103  * the accept() call could block us forever.
104  *
105  * do_pty = 0   Fork/exec inetd style
106  * do_pty = 1   Fork/exec using slirp.telnetd
107  * do_ptr = 2   Fork/exec using pty
108  */
109 int
fork_exec(struct socket * so,const char * ex,int do_pty)110 fork_exec(struct socket *so, const char *ex, int do_pty)
111 {
112 	int s;
113 	struct sockaddr_in addr;
114 	socklen_t addrlen = sizeof(addr);
115 	int opt;
116         int master = -1;
117 	const char *argv[256];
118 	/* don't want to clobber the original */
119 	char *bptr;
120 	const char *curarg;
121 	int c, i, ret;
122 
123 	DEBUG_CALL("fork_exec");
124 	DEBUG_ARG("so = %lx", (long)so);
125 	DEBUG_ARG("ex = %lx", (long)ex);
126 	DEBUG_ARG("do_pty = %lx", (long)do_pty);
127 
128 	if (do_pty == 2) {
129                 return 0;
130 	} else {
131 		addr.sin_family = AF_INET;
132 		addr.sin_port = 0;
133 		addr.sin_addr.s_addr = INADDR_ANY;
134 
135 		if ((s = qemu_socket(AF_INET, SOCK_STREAM, 0)) < 0 ||
136 		    bind(s, (struct sockaddr *)&addr, addrlen) < 0 ||
137 		    listen(s, 1) < 0) {
138 			lprint("Error: inet socket: %s\n", strerror(errno));
139 			closesocket(s);
140 
141 			return 0;
142 		}
143 	}
144 
145 	switch(fork()) {
146 	 case -1:
147 		lprint("Error: fork failed: %s\n", strerror(errno));
148 		close(s);
149 		if (do_pty == 2)
150 		   close(master);
151 		return 0;
152 
153 	 case 0:
154 		/* Set the DISPLAY */
155 		if (do_pty == 2) {
156 			(void) close(master);
157 #ifdef TIOCSCTTY /* XXXXX */
158 			(void) setsid();
159 			ioctl(s, TIOCSCTTY, (char *)NULL);
160 #endif
161 		} else {
162 			getsockname(s, (struct sockaddr *)&addr, &addrlen);
163 			close(s);
164 			/*
165 			 * Connect to the socket
166 			 * XXX If any of these fail, we're in trouble!
167 	 		 */
168 			s = qemu_socket(AF_INET, SOCK_STREAM, 0);
169 			addr.sin_addr = loopback_addr;
170                         do {
171                             ret = connect(s, (struct sockaddr *)&addr, addrlen);
172                         } while (ret < 0 && errno == EINTR);
173 		}
174 
175 		dup2(s, 0);
176 		dup2(s, 1);
177 		dup2(s, 2);
178 		for (s = getdtablesize() - 1; s >= 3; s--)
179 		   close(s);
180 
181 		i = 0;
182 		bptr = qemu_strdup(ex); /* No need to free() this */
183 		if (do_pty == 1) {
184 			/* Setup "slirp.telnetd -x" */
185 			argv[i++] = "slirp.telnetd";
186 			argv[i++] = "-x";
187 			argv[i++] = bptr;
188 		} else
189 		   do {
190 			/* Change the string into argv[] */
191 			curarg = bptr;
192 			while (*bptr != ' ' && *bptr != (char)0)
193 			   bptr++;
194 			c = *bptr;
195 			*bptr++ = (char)0;
196 			argv[i++] = strdup(curarg);
197 		   } while (c);
198 
199                 argv[i] = NULL;
200 		execvp(argv[0], (char **)argv);
201 
202 		/* Ooops, failed, let's tell the user why */
203         fprintf(stderr, "Error: execvp of %s failed: %s\n",
204                 argv[0], strerror(errno));
205 		close(0); close(1); close(2); /* XXX */
206 		exit(1);
207 
208 	 default:
209 		if (do_pty == 2) {
210 			close(s);
211 			so->s = master;
212 		} else {
213 			/*
214 			 * XXX this could block us...
215 			 * XXX Should set a timer here, and if accept() doesn't
216 		 	 * return after X seconds, declare it a failure
217 		 	 * The only reason this will block forever is if socket()
218 		 	 * of connect() fail in the child process
219 		 	 */
220                         do {
221                             so->s = accept(s, (struct sockaddr *)&addr, &addrlen);
222                         } while (so->s < 0 && errno == EINTR);
223                         closesocket(s);
224 			opt = 1;
225 			setsockopt(so->s,SOL_SOCKET,SO_REUSEADDR,(char *)&opt,sizeof(int));
226 			opt = 1;
227 			setsockopt(so->s,SOL_SOCKET,SO_OOBINLINE,(char *)&opt,sizeof(int));
228 		}
229 		fd_nonblock(so->s);
230 
231 		/* Append the telnet options now */
232                 if (so->so_m != NULL && do_pty == 1)  {
233 			sbappend(so, so->so_m);
234                         so->so_m = NULL;
235 		}
236 
237 		return 1;
238 	}
239 }
240 #endif
241 
242 #ifndef HAVE_STRDUP
243 char *
strdup(str)244 strdup(str)
245 	const char *str;
246 {
247 	char *bptr;
248 
249 	bptr = (char *)malloc(strlen(str)+1);
250 	strcpy(bptr, str);
251 
252 	return bptr;
253 }
254 #endif
255 
256 #include "monitor.h"
257 
lprint(const char * format,...)258 void lprint(const char *format, ...)
259 {
260     va_list args;
261 
262     va_start(args, format);
263     monitor_vprintf(default_mon, format, args);
264     va_end(args);
265 }
266 
267 void
u_sleep(int usec)268 u_sleep(int usec)
269 {
270 	struct timeval t;
271 	fd_set fdset;
272 
273 	FD_ZERO(&fdset);
274 
275 	t.tv_sec = 0;
276 	t.tv_usec = usec * 1000;
277 
278 	select(0, &fdset, &fdset, &fdset, &t);
279 }
280 
281 /*
282  * Set fd blocking and non-blocking
283  */
284 
285 void
fd_nonblock(int fd)286 fd_nonblock(int fd)
287 {
288 #ifdef FIONBIO
289 #ifdef _WIN32
290         unsigned long opt = 1;
291 #else
292         int opt = 1;
293 #endif
294 
295 	ioctlsocket(fd, FIONBIO, &opt);
296 #else
297 	int opt;
298 
299 	opt = fcntl(fd, F_GETFL, 0);
300 	opt |= O_NONBLOCK;
301 	fcntl(fd, F_SETFL, opt);
302 #endif
303 }
304 
305 void
fd_block(int fd)306 fd_block(int fd)
307 {
308 #ifdef FIONBIO
309 #ifdef _WIN32
310         unsigned long opt = 0;
311 #else
312 	int opt = 0;
313 #endif
314 
315 	ioctlsocket(fd, FIONBIO, &opt);
316 #else
317 	int opt;
318 
319 	opt = fcntl(fd, F_GETFL, 0);
320 	opt &= ~O_NONBLOCK;
321 	fcntl(fd, F_SETFL, opt);
322 #endif
323 }
324 
slirp_connection_info(Slirp * slirp,Monitor * mon)325 void slirp_connection_info(Slirp *slirp, Monitor *mon)
326 {
327     const char * const tcpstates[] = {
328         [TCPS_CLOSED]       = "CLOSED",
329         [TCPS_LISTEN]       = "LISTEN",
330         [TCPS_SYN_SENT]     = "SYN_SENT",
331         [TCPS_SYN_RECEIVED] = "SYN_RCVD",
332         [TCPS_ESTABLISHED]  = "ESTABLISHED",
333         [TCPS_CLOSE_WAIT]   = "CLOSE_WAIT",
334         [TCPS_FIN_WAIT_1]   = "FIN_WAIT_1",
335         [TCPS_CLOSING]      = "CLOSING",
336         [TCPS_LAST_ACK]     = "LAST_ACK",
337         [TCPS_FIN_WAIT_2]   = "FIN_WAIT_2",
338         [TCPS_TIME_WAIT]    = "TIME_WAIT",
339     };
340     struct in_addr dst_addr;
341     struct sockaddr_in src;
342     socklen_t src_len;
343     uint16_t dst_port;
344     struct socket *so;
345     const char *state;
346     char buf[20];
347     int n;
348 
349     monitor_printf(mon, "  Protocol[State]    FD  Source Address  Port   "
350                         "Dest. Address  Port RecvQ SendQ\n");
351 
352     for (so = slirp->tcb.so_next; so != &slirp->tcb; so = so->so_next) {
353         if (so->so_state & SS_HOSTFWD) {
354             state = "HOST_FORWARD";
355         } else if (so->so_tcpcb) {
356             state = tcpstates[so->so_tcpcb->t_state];
357         } else {
358             state = "NONE";
359         }
360         if (so->so_state & (SS_HOSTFWD | SS_INCOMING)) {
361             src_len = sizeof(src);
362             getsockname(so->s, (struct sockaddr *)&src, &src_len);
363             dst_addr = so->so_laddr;
364             dst_port = so->so_lport;
365         } else {
366             src.sin_addr = so->so_laddr;
367             src.sin_port = so->so_lport;
368             dst_addr = so->so_faddr;
369             dst_port = so->so_fport;
370         }
371         n = snprintf(buf, sizeof(buf), "  TCP[%s]", state);
372         memset(&buf[n], ' ', 19 - n);
373         buf[19] = 0;
374         monitor_printf(mon, "%s %3d %15s %5d ", buf, so->s,
375                        src.sin_addr.s_addr ? inet_ntoa(src.sin_addr) : "*",
376                        ntohs(src.sin_port));
377         monitor_printf(mon, "%15s %5d %5d %5d\n",
378                        inet_ntoa(dst_addr), ntohs(dst_port),
379                        so->so_rcv.sb_cc, so->so_snd.sb_cc);
380     }
381 
382     for (so = slirp->udb.so_next; so != &slirp->udb; so = so->so_next) {
383         if (so->so_state & SS_HOSTFWD) {
384             n = snprintf(buf, sizeof(buf), "  UDP[HOST_FORWARD]");
385             src_len = sizeof(src);
386             getsockname(so->s, (struct sockaddr *)&src, &src_len);
387             dst_addr = so->so_laddr;
388             dst_port = so->so_lport;
389         } else {
390             n = snprintf(buf, sizeof(buf), "  UDP[%d sec]",
391                          (so->so_expire - curtime) / 1000);
392             src.sin_addr = so->so_laddr;
393             src.sin_port = so->so_lport;
394             dst_addr = so->so_faddr;
395             dst_port = so->so_fport;
396         }
397         memset(&buf[n], ' ', 19 - n);
398         buf[19] = 0;
399         monitor_printf(mon, "%s %3d %15s %5d ", buf, so->s,
400                        src.sin_addr.s_addr ? inet_ntoa(src.sin_addr) : "*",
401                        ntohs(src.sin_port));
402         monitor_printf(mon, "%15s %5d %5d %5d\n",
403                        inet_ntoa(dst_addr), ntohs(dst_port),
404                        so->so_rcv.sb_cc, so->so_snd.sb_cc);
405     }
406 }
407