1*0Sstevel@tonic-gate /*
2*0Sstevel@tonic-gate  * CDDL HEADER START
3*0Sstevel@tonic-gate  *
4*0Sstevel@tonic-gate  * The contents of this file are subject to the terms of the
5*0Sstevel@tonic-gate  * Common Development and Distribution License, Version 1.0 only
6*0Sstevel@tonic-gate  * (the "License").  You may not use this file except in compliance
7*0Sstevel@tonic-gate  * with the License.
8*0Sstevel@tonic-gate  *
9*0Sstevel@tonic-gate  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10*0Sstevel@tonic-gate  * or http://www.opensolaris.org/os/licensing.
11*0Sstevel@tonic-gate  * See the License for the specific language governing permissions
12*0Sstevel@tonic-gate  * and limitations under the License.
13*0Sstevel@tonic-gate  *
14*0Sstevel@tonic-gate  * When distributing Covered Code, include this CDDL HEADER in each
15*0Sstevel@tonic-gate  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16*0Sstevel@tonic-gate  * If applicable, add the following below this CDDL HEADER, with the
17*0Sstevel@tonic-gate  * fields enclosed by brackets "[]" replaced with your own identifying
18*0Sstevel@tonic-gate  * information: Portions Copyright [yyyy] [name of copyright owner]
19*0Sstevel@tonic-gate  *
20*0Sstevel@tonic-gate  * CDDL HEADER END
21*0Sstevel@tonic-gate  *
22*0Sstevel@tonic-gate  * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
23*0Sstevel@tonic-gate  * Use is subject to license terms.
24*0Sstevel@tonic-gate  */
25*0Sstevel@tonic-gate 
26*0Sstevel@tonic-gate /*
27*0Sstevel@tonic-gate  * Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T
28*0Sstevel@tonic-gate  * All Rights Reserved.
29*0Sstevel@tonic-gate  */
30*0Sstevel@tonic-gate 
31*0Sstevel@tonic-gate /*
32*0Sstevel@tonic-gate  * University Copyright- Copyright (c) 1982, 1986, 1988
33*0Sstevel@tonic-gate  * The Regents of the University of California.
34*0Sstevel@tonic-gate  * All Rights Reserved.
35*0Sstevel@tonic-gate  *
36*0Sstevel@tonic-gate  * University Acknowledgment- Portions of this document are derived from
37*0Sstevel@tonic-gate  * software developed by the University of California, Berkeley, and its
38*0Sstevel@tonic-gate  * contributors.
39*0Sstevel@tonic-gate  */
40*0Sstevel@tonic-gate 
41*0Sstevel@tonic-gate #pragma ident	"%Z%%M%	%I%	%E% SMI"
42*0Sstevel@tonic-gate 
43*0Sstevel@tonic-gate /*
44*0Sstevel@tonic-gate  * Trivial file transfer protocol server.  A top level process runs in
45*0Sstevel@tonic-gate  * an infinite loop fielding new TFTP requests.  A child process,
46*0Sstevel@tonic-gate  * communicating via a pipe with the top level process, sends delayed
47*0Sstevel@tonic-gate  * NAKs for those that we can't handle.  A new child process is created
48*0Sstevel@tonic-gate  * to service each request that we can handle.  The top level process
49*0Sstevel@tonic-gate  * exits after a period of time during which no new requests are
50*0Sstevel@tonic-gate  * received.
51*0Sstevel@tonic-gate  */
52*0Sstevel@tonic-gate 
53*0Sstevel@tonic-gate #include <sys/types.h>
54*0Sstevel@tonic-gate #include <sys/socket.h>
55*0Sstevel@tonic-gate #include <sys/wait.h>
56*0Sstevel@tonic-gate #include <sys/stat.h>
57*0Sstevel@tonic-gate #include <sys/time.h>
58*0Sstevel@tonic-gate 
59*0Sstevel@tonic-gate #include <netinet/in.h>
60*0Sstevel@tonic-gate 
61*0Sstevel@tonic-gate #include <arpa/inet.h>
62*0Sstevel@tonic-gate #include <dirent.h>
63*0Sstevel@tonic-gate #include <signal.h>
64*0Sstevel@tonic-gate #include <stdio.h>
65*0Sstevel@tonic-gate #include <stdlib.h>
66*0Sstevel@tonic-gate #include <unistd.h>
67*0Sstevel@tonic-gate #include <errno.h>
68*0Sstevel@tonic-gate #include <ctype.h>
69*0Sstevel@tonic-gate #include <netdb.h>
70*0Sstevel@tonic-gate #include <setjmp.h>
71*0Sstevel@tonic-gate #include <syslog.h>
72*0Sstevel@tonic-gate #include <sys/param.h>
73*0Sstevel@tonic-gate #include <fcntl.h>
74*0Sstevel@tonic-gate #include <pwd.h>
75*0Sstevel@tonic-gate #include <string.h>
76*0Sstevel@tonic-gate #include <priv_utils.h>
77*0Sstevel@tonic-gate #include "tftpcommon.h"
78*0Sstevel@tonic-gate 
79*0Sstevel@tonic-gate #define	TIMEOUT		5
80*0Sstevel@tonic-gate #define	DELAY_SECS	3
81*0Sstevel@tonic-gate #define	DALLYSECS 60
82*0Sstevel@tonic-gate 
83*0Sstevel@tonic-gate #define	SYSLOG_MSG(message) \
84*0Sstevel@tonic-gate 	(syslog((((errno == ENETUNREACH) || (errno == EHOSTUNREACH) || \
85*0Sstevel@tonic-gate 		(errno == ECONNREFUSED)) ? LOG_WARNING : LOG_ERR), message))
86*0Sstevel@tonic-gate 
87*0Sstevel@tonic-gate static int			rexmtval = TIMEOUT;
88*0Sstevel@tonic-gate static int			maxtimeout = 5*TIMEOUT;
89*0Sstevel@tonic-gate static int			securetftp;
90*0Sstevel@tonic-gate static int			debug;
91*0Sstevel@tonic-gate static int			disable_pnp;
92*0Sstevel@tonic-gate static int			standalone;
93*0Sstevel@tonic-gate static uid_t			uid_nobody = UID_NOBODY;
94*0Sstevel@tonic-gate static uid_t			gid_nobody = GID_NOBODY;
95*0Sstevel@tonic-gate static int			reqsock = -1;
96*0Sstevel@tonic-gate 				/* file descriptor of request socket */
97*0Sstevel@tonic-gate static socklen_t		fromlen;
98*0Sstevel@tonic-gate static socklen_t		fromplen;
99*0Sstevel@tonic-gate static struct sockaddr_storage	client;
100*0Sstevel@tonic-gate static struct sockaddr_in6 	*sin6_ptr;
101*0Sstevel@tonic-gate static struct sockaddr_in	*sin_ptr;
102*0Sstevel@tonic-gate static struct sockaddr_in6	*from6_ptr;
103*0Sstevel@tonic-gate static struct sockaddr_in	*from_ptr;
104*0Sstevel@tonic-gate static int			addrfmly;
105*0Sstevel@tonic-gate static int			peer;
106*0Sstevel@tonic-gate static off_t			tsize;
107*0Sstevel@tonic-gate static tftpbuf			ackbuf;
108*0Sstevel@tonic-gate static struct sockaddr_storage	from;
109*0Sstevel@tonic-gate static boolean_t		tsize_set;
110*0Sstevel@tonic-gate static pid_t			child;
111*0Sstevel@tonic-gate 				/* pid of child handling delayed replys */
112*0Sstevel@tonic-gate static int			delay_fd [2];
113*0Sstevel@tonic-gate 				/* pipe for communicating with child */
114*0Sstevel@tonic-gate static FILE			*file;
115*0Sstevel@tonic-gate static char			*filename;
116*0Sstevel@tonic-gate 
117*0Sstevel@tonic-gate static union {
118*0Sstevel@tonic-gate 	struct tftphdr	hdr;
119*0Sstevel@tonic-gate 	char		data[SEGSIZE + 4];
120*0Sstevel@tonic-gate } buf;
121*0Sstevel@tonic-gate 
122*0Sstevel@tonic-gate static union {
123*0Sstevel@tonic-gate 	struct tftphdr	hdr;
124*0Sstevel@tonic-gate 	char		data[SEGSIZE];
125*0Sstevel@tonic-gate } oackbuf;
126*0Sstevel@tonic-gate 
127*0Sstevel@tonic-gate struct	delay_info {
128*0Sstevel@tonic-gate 	long	timestamp;		/* time request received */
129*0Sstevel@tonic-gate 	int	ecode;			/* error code to return */
130*0Sstevel@tonic-gate 	struct	sockaddr_storage from;	/* address of client */
131*0Sstevel@tonic-gate };
132*0Sstevel@tonic-gate 
133*0Sstevel@tonic-gate int	blocksize = SEGSIZE;	/* Number of data bytes in a DATA packet */
134*0Sstevel@tonic-gate 
135*0Sstevel@tonic-gate /*
136*0Sstevel@tonic-gate  * Default directory for unqualified names
137*0Sstevel@tonic-gate  * Used by TFTP boot procedures
138*0Sstevel@tonic-gate  */
139*0Sstevel@tonic-gate static char	*homedir = "/tftpboot";
140*0Sstevel@tonic-gate 
141*0Sstevel@tonic-gate struct formats {
142*0Sstevel@tonic-gate 	char	*f_mode;
143*0Sstevel@tonic-gate 	int	(*f_validate)(int);
144*0Sstevel@tonic-gate 	void	(*f_send)(struct formats *, int);
145*0Sstevel@tonic-gate 	void	(*f_recv)(struct formats *, int);
146*0Sstevel@tonic-gate 	int	f_convert;
147*0Sstevel@tonic-gate };
148*0Sstevel@tonic-gate 
149*0Sstevel@tonic-gate static void	delayed_responder(void);
150*0Sstevel@tonic-gate static void	tftp(struct tftphdr *, int);
151*0Sstevel@tonic-gate static int	validate_filename(int);
152*0Sstevel@tonic-gate static void	tftpd_sendfile(struct formats *, int);
153*0Sstevel@tonic-gate static void	tftpd_recvfile(struct formats *, int);
154*0Sstevel@tonic-gate static void	nak(int);
155*0Sstevel@tonic-gate static char	*blksize_handler(int, char *, int *);
156*0Sstevel@tonic-gate static char	*timeout_handler(int, char *, int *);
157*0Sstevel@tonic-gate static char	*tsize_handler(int, char *, int *);
158*0Sstevel@tonic-gate 
159*0Sstevel@tonic-gate static struct formats formats[] = {
160*0Sstevel@tonic-gate 	{ "netascii",	validate_filename, tftpd_sendfile, tftpd_recvfile, 1 },
161*0Sstevel@tonic-gate 	{ "octet",	validate_filename, tftpd_sendfile, tftpd_recvfile, 0 },
162*0Sstevel@tonic-gate 	{ NULL }
163*0Sstevel@tonic-gate };
164*0Sstevel@tonic-gate 
165*0Sstevel@tonic-gate struct options {
166*0Sstevel@tonic-gate 	char	*opt_name;
167*0Sstevel@tonic-gate 	char	*(*opt_handler)(int, char *, int *);
168*0Sstevel@tonic-gate };
169*0Sstevel@tonic-gate 
170*0Sstevel@tonic-gate static struct options options[] = {
171*0Sstevel@tonic-gate 	{ "blksize",	blksize_handler },
172*0Sstevel@tonic-gate 	{ "timeout",	timeout_handler },
173*0Sstevel@tonic-gate 	{ "tsize",	tsize_handler },
174*0Sstevel@tonic-gate 	{ NULL }
175*0Sstevel@tonic-gate };
176*0Sstevel@tonic-gate 
177*0Sstevel@tonic-gate static char		optbuf[MAX_OPTVAL_LEN];
178*0Sstevel@tonic-gate static int		timeout;
179*0Sstevel@tonic-gate static sigjmp_buf	timeoutbuf;
180*0Sstevel@tonic-gate 
181*0Sstevel@tonic-gate int
182*0Sstevel@tonic-gate main(int argc, char **argv)
183*0Sstevel@tonic-gate {
184*0Sstevel@tonic-gate 	struct tftphdr *tp;
185*0Sstevel@tonic-gate 	int n;
186*0Sstevel@tonic-gate 	int c;
187*0Sstevel@tonic-gate 	struct	passwd *pwd;		/* for "nobody" entry */
188*0Sstevel@tonic-gate 	struct in_addr ipv4addr;
189*0Sstevel@tonic-gate 	char abuf[INET6_ADDRSTRLEN];
190*0Sstevel@tonic-gate 	socklen_t addrlen;
191*0Sstevel@tonic-gate 
192*0Sstevel@tonic-gate 	openlog("tftpd", LOG_PID, LOG_DAEMON);
193*0Sstevel@tonic-gate 
194*0Sstevel@tonic-gate 	pwd = getpwnam("nobody");
195*0Sstevel@tonic-gate 	if (pwd != NULL) {
196*0Sstevel@tonic-gate 		uid_nobody = pwd->pw_uid;
197*0Sstevel@tonic-gate 		gid_nobody = pwd->pw_gid;
198*0Sstevel@tonic-gate 	}
199*0Sstevel@tonic-gate 
200*0Sstevel@tonic-gate 	(void) __init_daemon_priv(
201*0Sstevel@tonic-gate 		PU_LIMITPRIVS,
202*0Sstevel@tonic-gate 		uid_nobody, gid_nobody,
203*0Sstevel@tonic-gate 		PRIV_PROC_FORK, PRIV_PROC_CHROOT, NULL);
204*0Sstevel@tonic-gate 
205*0Sstevel@tonic-gate 	/*
206*0Sstevel@tonic-gate 	 *  Limit set is still "all."  Trim it down to just what we need:
207*0Sstevel@tonic-gate 	 *  fork and chroot.
208*0Sstevel@tonic-gate 	 */
209*0Sstevel@tonic-gate 	(void) priv_set(PRIV_SET,
210*0Sstevel@tonic-gate 	    PRIV_ALLSETS, PRIV_PROC_FORK, PRIV_PROC_CHROOT, NULL);
211*0Sstevel@tonic-gate 	(void) priv_set(PRIV_SET, PRIV_EFFECTIVE, NULL);
212*0Sstevel@tonic-gate 	(void) priv_set(PRIV_SET, PRIV_INHERITABLE, NULL);
213*0Sstevel@tonic-gate 
214*0Sstevel@tonic-gate 	while ((c = getopt(argc, argv, "dspS")) != EOF)
215*0Sstevel@tonic-gate 		switch (c) {
216*0Sstevel@tonic-gate 		case 'd':		/* enable debug */
217*0Sstevel@tonic-gate 			debug++;
218*0Sstevel@tonic-gate 			continue;
219*0Sstevel@tonic-gate 		case 's':		/* secure daemon */
220*0Sstevel@tonic-gate 			securetftp = 1;
221*0Sstevel@tonic-gate 			continue;
222*0Sstevel@tonic-gate 		case 'p':		/* disable name pnp mapping */
223*0Sstevel@tonic-gate 			disable_pnp = 1;
224*0Sstevel@tonic-gate 			continue;
225*0Sstevel@tonic-gate 		case 'S':
226*0Sstevel@tonic-gate 			standalone = 1;
227*0Sstevel@tonic-gate 			continue;
228*0Sstevel@tonic-gate 		case '?':
229*0Sstevel@tonic-gate 		default:
230*0Sstevel@tonic-gate usage:
231*0Sstevel@tonic-gate 			(void) fprintf(stderr,
232*0Sstevel@tonic-gate 			    "usage:  %s [-spd] [home-directory]\n", argv[0]);
233*0Sstevel@tonic-gate 			for (; optind < argc; optind++)
234*0Sstevel@tonic-gate 				syslog(LOG_ERR, "bad argument %s",
235*0Sstevel@tonic-gate 				    argv[optind]);
236*0Sstevel@tonic-gate 			exit(1);
237*0Sstevel@tonic-gate 		}
238*0Sstevel@tonic-gate 
239*0Sstevel@tonic-gate 	if (optind < argc)
240*0Sstevel@tonic-gate 		if (optind == argc - 1 && *argv [optind] == '/')
241*0Sstevel@tonic-gate 			homedir = argv [optind];
242*0Sstevel@tonic-gate 		else
243*0Sstevel@tonic-gate 			goto usage;
244*0Sstevel@tonic-gate 
245*0Sstevel@tonic-gate 	if (pipe(delay_fd) < 0) {
246*0Sstevel@tonic-gate 		syslog(LOG_ERR, "pipe (main): %m");
247*0Sstevel@tonic-gate 		exit(1);
248*0Sstevel@tonic-gate 	}
249*0Sstevel@tonic-gate 
250*0Sstevel@tonic-gate 	(void) sigset(SIGCHLD, SIG_IGN); /* no zombies please */
251*0Sstevel@tonic-gate 
252*0Sstevel@tonic-gate 	if (standalone) {
253*0Sstevel@tonic-gate 		socklen_t clientlen;
254*0Sstevel@tonic-gate 
255*0Sstevel@tonic-gate 		sin6_ptr = (struct sockaddr_in6 *)&client;
256*0Sstevel@tonic-gate 		clientlen = sizeof (struct sockaddr_in6);
257*0Sstevel@tonic-gate 		reqsock = socket(AF_INET6, SOCK_DGRAM, 0);
258*0Sstevel@tonic-gate 		if (reqsock == -1) {
259*0Sstevel@tonic-gate 			perror("socket");
260*0Sstevel@tonic-gate 			exit(1);
261*0Sstevel@tonic-gate 		}
262*0Sstevel@tonic-gate 		(void) memset(&client, 0, clientlen);
263*0Sstevel@tonic-gate 		sin6_ptr->sin6_family = AF_INET6;
264*0Sstevel@tonic-gate 		sin6_ptr->sin6_port = htons(IPPORT_TFTP);
265*0Sstevel@tonic-gate 		if (bind(reqsock, (struct sockaddr *)&client,
266*0Sstevel@tonic-gate 		    clientlen) == -1) {
267*0Sstevel@tonic-gate 			perror("bind");
268*0Sstevel@tonic-gate 			exit(1);
269*0Sstevel@tonic-gate 		}
270*0Sstevel@tonic-gate 		if (debug)
271*0Sstevel@tonic-gate 			(void) puts("running in standalone mode...");
272*0Sstevel@tonic-gate 	} else {
273*0Sstevel@tonic-gate 		/* request socket passed on fd 0 by inetd */
274*0Sstevel@tonic-gate 		reqsock = 0;
275*0Sstevel@tonic-gate 	}
276*0Sstevel@tonic-gate 	if (debug) {
277*0Sstevel@tonic-gate 		int on = 1;
278*0Sstevel@tonic-gate 
279*0Sstevel@tonic-gate 		(void) setsockopt(reqsock, SOL_SOCKET, SO_DEBUG,
280*0Sstevel@tonic-gate 		    (char *)&on, sizeof (on));
281*0Sstevel@tonic-gate 	}
282*0Sstevel@tonic-gate 
283*0Sstevel@tonic-gate 	(void) chdir(homedir);
284*0Sstevel@tonic-gate 
285*0Sstevel@tonic-gate 	(void) priv_set(PRIV_SET, PRIV_EFFECTIVE, PRIV_PROC_FORK, NULL);
286*0Sstevel@tonic-gate 	if ((child = fork()) < 0) {
287*0Sstevel@tonic-gate 		syslog(LOG_ERR, "fork (main): %m");
288*0Sstevel@tonic-gate 		exit(1);
289*0Sstevel@tonic-gate 	}
290*0Sstevel@tonic-gate 	(void) priv_set(PRIV_SET, PRIV_EFFECTIVE, NULL);
291*0Sstevel@tonic-gate 
292*0Sstevel@tonic-gate 	if (child == 0) {
293*0Sstevel@tonic-gate 		(void) priv_set(PRIV_SET, PRIV_ALLSETS, NULL);
294*0Sstevel@tonic-gate 		delayed_responder();
295*0Sstevel@tonic-gate 	} /* child */
296*0Sstevel@tonic-gate 
297*0Sstevel@tonic-gate 	/* close read side of pipe */
298*0Sstevel@tonic-gate 	(void) close(delay_fd[0]);
299*0Sstevel@tonic-gate 
300*0Sstevel@tonic-gate 
301*0Sstevel@tonic-gate 	/*
302*0Sstevel@tonic-gate 	 * Top level handling of incomming tftp requests.  Read a request
303*0Sstevel@tonic-gate 	 * and pass it off to be handled.  If request is valid, handling
304*0Sstevel@tonic-gate 	 * forks off and parent returns to this loop.  If no new requests
305*0Sstevel@tonic-gate 	 * are received for DALLYSECS, exit and return to inetd.
306*0Sstevel@tonic-gate 	 */
307*0Sstevel@tonic-gate 
308*0Sstevel@tonic-gate 	for (;;) {
309*0Sstevel@tonic-gate 		fd_set readfds;
310*0Sstevel@tonic-gate 		struct timeval dally;
311*0Sstevel@tonic-gate 
312*0Sstevel@tonic-gate 		FD_ZERO(&readfds);
313*0Sstevel@tonic-gate 		FD_SET(reqsock, &readfds);
314*0Sstevel@tonic-gate 		dally.tv_sec = DALLYSECS;
315*0Sstevel@tonic-gate 		dally.tv_usec = 0;
316*0Sstevel@tonic-gate 
317*0Sstevel@tonic-gate 		n = select(reqsock + 1, &readfds, NULL, NULL, &dally);
318*0Sstevel@tonic-gate 		if (n < 0) {
319*0Sstevel@tonic-gate 			if (errno == EINTR)
320*0Sstevel@tonic-gate 				continue;
321*0Sstevel@tonic-gate 			syslog(LOG_ERR, "select: %m");
322*0Sstevel@tonic-gate 			(void) kill(child, SIGKILL);
323*0Sstevel@tonic-gate 			exit(1);
324*0Sstevel@tonic-gate 		}
325*0Sstevel@tonic-gate 		if (n == 0) {
326*0Sstevel@tonic-gate 			/* Select timed out.  Its time to die. */
327*0Sstevel@tonic-gate 			if (standalone)
328*0Sstevel@tonic-gate 				continue;
329*0Sstevel@tonic-gate 			else {
330*0Sstevel@tonic-gate 				(void) kill(child, SIGKILL);
331*0Sstevel@tonic-gate 				exit(0);
332*0Sstevel@tonic-gate 			}
333*0Sstevel@tonic-gate 		}
334*0Sstevel@tonic-gate 		addrlen = sizeof (from);
335*0Sstevel@tonic-gate 		if (getsockname(reqsock, (struct sockaddr  *)&from,
336*0Sstevel@tonic-gate 		    &addrlen) < 0) {
337*0Sstevel@tonic-gate 			syslog(LOG_ERR, "getsockname: %m");
338*0Sstevel@tonic-gate 			exit(1);
339*0Sstevel@tonic-gate 		}
340*0Sstevel@tonic-gate 
341*0Sstevel@tonic-gate 		switch (from.ss_family) {
342*0Sstevel@tonic-gate 		case AF_INET:
343*0Sstevel@tonic-gate 			fromlen = (socklen_t)sizeof (struct sockaddr_in);
344*0Sstevel@tonic-gate 			break;
345*0Sstevel@tonic-gate 		case AF_INET6:
346*0Sstevel@tonic-gate 			fromlen = (socklen_t)sizeof (struct sockaddr_in6);
347*0Sstevel@tonic-gate 			break;
348*0Sstevel@tonic-gate 		default:
349*0Sstevel@tonic-gate 			syslog(LOG_ERR,
350*0Sstevel@tonic-gate 			    "Unknown address Family on peer connection %d",
351*0Sstevel@tonic-gate 			    from.ss_family);
352*0Sstevel@tonic-gate 			exit(1);
353*0Sstevel@tonic-gate 		}
354*0Sstevel@tonic-gate 
355*0Sstevel@tonic-gate 		n = recvfrom(reqsock, &buf, sizeof (buf), 0,
356*0Sstevel@tonic-gate 			(struct sockaddr *)&from, &fromlen);
357*0Sstevel@tonic-gate 		if (n < 0) {
358*0Sstevel@tonic-gate 			if (errno == EINTR)
359*0Sstevel@tonic-gate 				continue;
360*0Sstevel@tonic-gate 			if (standalone)
361*0Sstevel@tonic-gate 				perror("recvfrom");
362*0Sstevel@tonic-gate 			else
363*0Sstevel@tonic-gate 				syslog(LOG_ERR, "recvfrom: %m");
364*0Sstevel@tonic-gate 			(void) kill(child, SIGKILL);
365*0Sstevel@tonic-gate 			exit(1);
366*0Sstevel@tonic-gate 		}
367*0Sstevel@tonic-gate 
368*0Sstevel@tonic-gate 		(void) alarm(0);
369*0Sstevel@tonic-gate 
370*0Sstevel@tonic-gate 		switch (from.ss_family) {
371*0Sstevel@tonic-gate 		case AF_INET:
372*0Sstevel@tonic-gate 			addrfmly = AF_INET;
373*0Sstevel@tonic-gate 			fromplen = sizeof (struct sockaddr_in);
374*0Sstevel@tonic-gate 			sin_ptr = (struct sockaddr_in *)&client;
375*0Sstevel@tonic-gate 			(void) memset(&client, 0, fromplen);
376*0Sstevel@tonic-gate 			sin_ptr->sin_family = AF_INET;
377*0Sstevel@tonic-gate 			break;
378*0Sstevel@tonic-gate 		case AF_INET6:
379*0Sstevel@tonic-gate 			addrfmly = AF_INET6;
380*0Sstevel@tonic-gate 			fromplen = sizeof (struct sockaddr_in6);
381*0Sstevel@tonic-gate 			sin6_ptr = (struct sockaddr_in6 *)&client;
382*0Sstevel@tonic-gate 			(void) memset(&client, 0, fromplen);
383*0Sstevel@tonic-gate 			sin6_ptr->sin6_family = AF_INET6;
384*0Sstevel@tonic-gate 			break;
385*0Sstevel@tonic-gate 		default:
386*0Sstevel@tonic-gate 			syslog(LOG_ERR,
387*0Sstevel@tonic-gate 			    "Unknown address Family on peer connection");
388*0Sstevel@tonic-gate 			exit(1);
389*0Sstevel@tonic-gate 		}
390*0Sstevel@tonic-gate 		peer = socket(addrfmly, SOCK_DGRAM, 0);
391*0Sstevel@tonic-gate 		if (peer < 0) {
392*0Sstevel@tonic-gate 			if (standalone)
393*0Sstevel@tonic-gate 				perror("socket (main)");
394*0Sstevel@tonic-gate 			else
395*0Sstevel@tonic-gate 				syslog(LOG_ERR, "socket (main): %m");
396*0Sstevel@tonic-gate 			(void) kill(child, SIGKILL);
397*0Sstevel@tonic-gate 			exit(1);
398*0Sstevel@tonic-gate 		}
399*0Sstevel@tonic-gate 		if (debug) {
400*0Sstevel@tonic-gate 			int on = 1;
401*0Sstevel@tonic-gate 
402*0Sstevel@tonic-gate 			(void) setsockopt(peer, SOL_SOCKET, SO_DEBUG,
403*0Sstevel@tonic-gate 			    (char *)&on, sizeof (on));
404*0Sstevel@tonic-gate 		}
405*0Sstevel@tonic-gate 
406*0Sstevel@tonic-gate 		if (bind(peer, (struct sockaddr *)&client, fromplen) < 0) {
407*0Sstevel@tonic-gate 			if (standalone)
408*0Sstevel@tonic-gate 				perror("bind (main)");
409*0Sstevel@tonic-gate 			else
410*0Sstevel@tonic-gate 				syslog(LOG_ERR, "bind (main): %m");
411*0Sstevel@tonic-gate 			(void) kill(child, SIGKILL);
412*0Sstevel@tonic-gate 			exit(1);
413*0Sstevel@tonic-gate 		}
414*0Sstevel@tonic-gate 		if (standalone && debug) {
415*0Sstevel@tonic-gate 			sin6_ptr = (struct sockaddr_in6 *)&client;
416*0Sstevel@tonic-gate 			from6_ptr = (struct sockaddr_in6 *)&from;
417*0Sstevel@tonic-gate 			if (IN6_IS_ADDR_V4MAPPED(&from6_ptr->sin6_addr)) {
418*0Sstevel@tonic-gate 				IN6_V4MAPPED_TO_INADDR(&from6_ptr->sin6_addr,
419*0Sstevel@tonic-gate 				    &ipv4addr);
420*0Sstevel@tonic-gate 				(void) inet_ntop(AF_INET, &ipv4addr, abuf,
421*0Sstevel@tonic-gate 				    sizeof (abuf));
422*0Sstevel@tonic-gate 			} else {
423*0Sstevel@tonic-gate 				(void) inet_ntop(AF_INET6,
424*0Sstevel@tonic-gate 				    &from6_ptr->sin6_addr, abuf,
425*0Sstevel@tonic-gate 				    sizeof (abuf));
426*0Sstevel@tonic-gate 			}
427*0Sstevel@tonic-gate 			/* get local port */
428*0Sstevel@tonic-gate 			if (getsockname(peer, (struct sockaddr *)&client,
429*0Sstevel@tonic-gate 			    &fromplen) < 0)
430*0Sstevel@tonic-gate 				perror("getsockname (main)");
431*0Sstevel@tonic-gate 			(void) fprintf(stderr,
432*0Sstevel@tonic-gate 			    "request from %s port %d; local port %d\n",
433*0Sstevel@tonic-gate 			    abuf, from6_ptr->sin6_port, sin6_ptr->sin6_port);
434*0Sstevel@tonic-gate 		}
435*0Sstevel@tonic-gate 		tp = &buf.hdr;
436*0Sstevel@tonic-gate 		tp->th_opcode = ntohs((ushort_t)tp->th_opcode);
437*0Sstevel@tonic-gate 		if (tp->th_opcode == RRQ || tp->th_opcode == WRQ)
438*0Sstevel@tonic-gate 			tftp(tp, n);
439*0Sstevel@tonic-gate 
440*0Sstevel@tonic-gate 		(void) close(peer);
441*0Sstevel@tonic-gate 		(void) fclose(file);
442*0Sstevel@tonic-gate 	}
443*0Sstevel@tonic-gate 
444*0Sstevel@tonic-gate 	/*NOTREACHED*/
445*0Sstevel@tonic-gate 	return (0);
446*0Sstevel@tonic-gate }
447*0Sstevel@tonic-gate 
448*0Sstevel@tonic-gate static void
449*0Sstevel@tonic-gate delayed_responder(void)
450*0Sstevel@tonic-gate {
451*0Sstevel@tonic-gate 	struct delay_info dinfo;
452*0Sstevel@tonic-gate 	long now;
453*0Sstevel@tonic-gate 
454*0Sstevel@tonic-gate 	/* we don't use the descriptors passed in to the parent */
455*0Sstevel@tonic-gate 	(void) close(0);
456*0Sstevel@tonic-gate 	(void) close(1);
457*0Sstevel@tonic-gate 	if (standalone)
458*0Sstevel@tonic-gate 		(void) close(reqsock);
459*0Sstevel@tonic-gate 
460*0Sstevel@tonic-gate 	/* close write side of pipe */
461*0Sstevel@tonic-gate 	(void) close(delay_fd[1]);
462*0Sstevel@tonic-gate 
463*0Sstevel@tonic-gate 	for (;;) {
464*0Sstevel@tonic-gate 		int n;
465*0Sstevel@tonic-gate 
466*0Sstevel@tonic-gate 		if ((n = read(delay_fd[0], &dinfo,
467*0Sstevel@tonic-gate 		    sizeof (dinfo))) != sizeof (dinfo)) {
468*0Sstevel@tonic-gate 			if (n < 0) {
469*0Sstevel@tonic-gate 				if (errno == EINTR)
470*0Sstevel@tonic-gate 					continue;
471*0Sstevel@tonic-gate 				if (standalone)
472*0Sstevel@tonic-gate 					perror("read from pipe "
473*0Sstevel@tonic-gate 					    "(delayed responder)");
474*0Sstevel@tonic-gate 				else
475*0Sstevel@tonic-gate 					syslog(LOG_ERR, "read from pipe: %m");
476*0Sstevel@tonic-gate 			}
477*0Sstevel@tonic-gate 			exit(1);
478*0Sstevel@tonic-gate 		}
479*0Sstevel@tonic-gate 		switch (dinfo.from.ss_family) {
480*0Sstevel@tonic-gate 		case AF_INET:
481*0Sstevel@tonic-gate 			addrfmly = AF_INET;
482*0Sstevel@tonic-gate 			fromplen = sizeof (struct sockaddr_in);
483*0Sstevel@tonic-gate 			sin_ptr = (struct sockaddr_in *)&client;
484*0Sstevel@tonic-gate 			(void) memset(&client, 0, fromplen);
485*0Sstevel@tonic-gate 			sin_ptr->sin_family = AF_INET;
486*0Sstevel@tonic-gate 			break;
487*0Sstevel@tonic-gate 		case AF_INET6:
488*0Sstevel@tonic-gate 			addrfmly = AF_INET6;
489*0Sstevel@tonic-gate 			fromplen = sizeof (struct sockaddr_in6);
490*0Sstevel@tonic-gate 			sin6_ptr = (struct sockaddr_in6 *)&client;
491*0Sstevel@tonic-gate 			(void) memset(&client, 0, fromplen);
492*0Sstevel@tonic-gate 			sin6_ptr->sin6_family = AF_INET6;
493*0Sstevel@tonic-gate 			break;
494*0Sstevel@tonic-gate 		}
495*0Sstevel@tonic-gate 		peer = socket(addrfmly, SOCK_DGRAM, 0);
496*0Sstevel@tonic-gate 		if (peer == -1) {
497*0Sstevel@tonic-gate 			if (standalone)
498*0Sstevel@tonic-gate 				perror("socket (delayed responder)");
499*0Sstevel@tonic-gate 			else
500*0Sstevel@tonic-gate 				syslog(LOG_ERR, "socket (delay): %m");
501*0Sstevel@tonic-gate 			exit(1);
502*0Sstevel@tonic-gate 		}
503*0Sstevel@tonic-gate 		if (debug) {
504*0Sstevel@tonic-gate 			int on = 1;
505*0Sstevel@tonic-gate 
506*0Sstevel@tonic-gate 			(void) setsockopt(peer, SOL_SOCKET, SO_DEBUG,
507*0Sstevel@tonic-gate 			    (char *)&on, sizeof (on));
508*0Sstevel@tonic-gate 		}
509*0Sstevel@tonic-gate 
510*0Sstevel@tonic-gate 		if (bind(peer, (struct sockaddr *)&client, fromplen) < 0) {
511*0Sstevel@tonic-gate 			if (standalone)
512*0Sstevel@tonic-gate 				perror("bind (delayed responder)");
513*0Sstevel@tonic-gate 			else
514*0Sstevel@tonic-gate 				syslog(LOG_ERR, "bind (delay): %m");
515*0Sstevel@tonic-gate 			exit(1);
516*0Sstevel@tonic-gate 		}
517*0Sstevel@tonic-gate 		if (client.ss_family == AF_INET) {
518*0Sstevel@tonic-gate 			from_ptr = (struct sockaddr_in *)&dinfo.from;
519*0Sstevel@tonic-gate 			from_ptr->sin_family = AF_INET;
520*0Sstevel@tonic-gate 		} else {
521*0Sstevel@tonic-gate 			from6_ptr = (struct sockaddr_in6 *)&dinfo.from;
522*0Sstevel@tonic-gate 			from6_ptr->sin6_family = AF_INET6;
523*0Sstevel@tonic-gate 		}
524*0Sstevel@tonic-gate 		/*
525*0Sstevel@tonic-gate 		 * Since a request hasn't been received from the client
526*0Sstevel@tonic-gate 		 * before the delayed responder process is forked, the
527*0Sstevel@tonic-gate 		 * from variable is uninitialized.  So set it to contain
528*0Sstevel@tonic-gate 		 * the client address.
529*0Sstevel@tonic-gate 		 */
530*0Sstevel@tonic-gate 		from = dinfo.from;
531*0Sstevel@tonic-gate 
532*0Sstevel@tonic-gate 		/*
533*0Sstevel@tonic-gate 		 * only sleep if DELAY_SECS has not elapsed since
534*0Sstevel@tonic-gate 		 * original request was received.  Ensure that `now'
535*0Sstevel@tonic-gate 		 * is not earlier than `dinfo.timestamp'
536*0Sstevel@tonic-gate 		 */
537*0Sstevel@tonic-gate 		now = time(0);
538*0Sstevel@tonic-gate 		if ((uint_t)(now - dinfo.timestamp) < DELAY_SECS)
539*0Sstevel@tonic-gate 			(void) sleep(DELAY_SECS - (now - dinfo.timestamp));
540*0Sstevel@tonic-gate 		nak(dinfo.ecode);
541*0Sstevel@tonic-gate 		(void) close(peer);
542*0Sstevel@tonic-gate 	} /* for */
543*0Sstevel@tonic-gate 
544*0Sstevel@tonic-gate 	/* NOTREACHED */
545*0Sstevel@tonic-gate }
546*0Sstevel@tonic-gate 
547*0Sstevel@tonic-gate /*
548*0Sstevel@tonic-gate  * Handle the Blocksize option.
549*0Sstevel@tonic-gate  * Return the blksize option value string to include in the OACK reply.
550*0Sstevel@tonic-gate  */
551*0Sstevel@tonic-gate /*ARGSUSED*/
552*0Sstevel@tonic-gate static char *
553*0Sstevel@tonic-gate blksize_handler(int opcode, char *optval, int *errcode)
554*0Sstevel@tonic-gate {
555*0Sstevel@tonic-gate 	char *endp;
556*0Sstevel@tonic-gate 	int value;
557*0Sstevel@tonic-gate 
558*0Sstevel@tonic-gate 	*errcode = -1;
559*0Sstevel@tonic-gate 	errno = 0;
560*0Sstevel@tonic-gate 	value = (int)strtol(optval, &endp, 10);
561*0Sstevel@tonic-gate 	if (errno != 0 || value < MIN_BLKSIZE || *endp != '\0')
562*0Sstevel@tonic-gate 		return (NULL);
563*0Sstevel@tonic-gate 	/*
564*0Sstevel@tonic-gate 	 * As the blksize value in the OACK reply can be less than the value
565*0Sstevel@tonic-gate 	 * requested, to support broken clients if the value requested is larger
566*0Sstevel@tonic-gate 	 * than allowed in the RFC, reply with the maximum value permitted.
567*0Sstevel@tonic-gate 	 */
568*0Sstevel@tonic-gate 	if (value > MAX_BLKSIZE)
569*0Sstevel@tonic-gate 		value = MAX_BLKSIZE;
570*0Sstevel@tonic-gate 
571*0Sstevel@tonic-gate 	blocksize = value;
572*0Sstevel@tonic-gate 	(void) snprintf(optbuf, sizeof (optbuf), "%d", blocksize);
573*0Sstevel@tonic-gate 	return (optbuf);
574*0Sstevel@tonic-gate }
575*0Sstevel@tonic-gate 
576*0Sstevel@tonic-gate /*
577*0Sstevel@tonic-gate  * Handle the Timeout Interval option.
578*0Sstevel@tonic-gate  * Return the timeout option value string to include in the OACK reply.
579*0Sstevel@tonic-gate  */
580*0Sstevel@tonic-gate /*ARGSUSED*/
581*0Sstevel@tonic-gate static char *
582*0Sstevel@tonic-gate timeout_handler(int opcode, char *optval, int *errcode)
583*0Sstevel@tonic-gate {
584*0Sstevel@tonic-gate 	char *endp;
585*0Sstevel@tonic-gate 	int value;
586*0Sstevel@tonic-gate 
587*0Sstevel@tonic-gate 	*errcode = -1;
588*0Sstevel@tonic-gate 	errno = 0;
589*0Sstevel@tonic-gate 	value = (int)strtol(optval, &endp, 10);
590*0Sstevel@tonic-gate 	if (errno != 0 || *endp != '\0')
591*0Sstevel@tonic-gate 		return (NULL);
592*0Sstevel@tonic-gate 	/*
593*0Sstevel@tonic-gate 	 * The timeout value in the OACK reply must match the value specified
594*0Sstevel@tonic-gate 	 * by the client, so if an invalid timeout is requested don't include
595*0Sstevel@tonic-gate 	 * the timeout option in the OACK reply.
596*0Sstevel@tonic-gate 	 */
597*0Sstevel@tonic-gate 	if (value < MIN_TIMEOUT || value > MAX_TIMEOUT)
598*0Sstevel@tonic-gate 		return (NULL);
599*0Sstevel@tonic-gate 
600*0Sstevel@tonic-gate 	rexmtval = value;
601*0Sstevel@tonic-gate 	maxtimeout = 5 * rexmtval;
602*0Sstevel@tonic-gate 	(void) snprintf(optbuf, sizeof (optbuf), "%d", rexmtval);
603*0Sstevel@tonic-gate 	return (optbuf);
604*0Sstevel@tonic-gate }
605*0Sstevel@tonic-gate 
606*0Sstevel@tonic-gate /*
607*0Sstevel@tonic-gate  * Handle the Transfer Size option.
608*0Sstevel@tonic-gate  * Return the tsize option value string to include in the OACK reply.
609*0Sstevel@tonic-gate  */
610*0Sstevel@tonic-gate static char *
611*0Sstevel@tonic-gate tsize_handler(int opcode, char *optval, int *errcode)
612*0Sstevel@tonic-gate {
613*0Sstevel@tonic-gate 	char *endp;
614*0Sstevel@tonic-gate 	longlong_t value;
615*0Sstevel@tonic-gate 
616*0Sstevel@tonic-gate 	*errcode = -1;
617*0Sstevel@tonic-gate 	errno = 0;
618*0Sstevel@tonic-gate 	value = strtoll(optval, &endp, 10);
619*0Sstevel@tonic-gate 	if (errno != 0 || value < 0 || *endp != '\0')
620*0Sstevel@tonic-gate 		return (NULL);
621*0Sstevel@tonic-gate 
622*0Sstevel@tonic-gate 	if (opcode == RRQ) {
623*0Sstevel@tonic-gate 		if (tsize_set == B_FALSE)
624*0Sstevel@tonic-gate 			return (NULL);
625*0Sstevel@tonic-gate 		/*
626*0Sstevel@tonic-gate 		 * The tsize value should be 0 for a read request, but to
627*0Sstevel@tonic-gate 		 * support broken clients we don't check that it is.
628*0Sstevel@tonic-gate 		 */
629*0Sstevel@tonic-gate 	} else {
630*0Sstevel@tonic-gate #if _FILE_OFFSET_BITS == 32
631*0Sstevel@tonic-gate 		if (value > MAXOFF_T) {
632*0Sstevel@tonic-gate 			*errcode = ENOSPACE;
633*0Sstevel@tonic-gate 			return (NULL);
634*0Sstevel@tonic-gate 		}
635*0Sstevel@tonic-gate #endif
636*0Sstevel@tonic-gate 		tsize = value;
637*0Sstevel@tonic-gate 		tsize_set = B_TRUE;
638*0Sstevel@tonic-gate 	}
639*0Sstevel@tonic-gate 	(void) snprintf(optbuf, sizeof (optbuf), OFF_T_FMT, tsize);
640*0Sstevel@tonic-gate 	return (optbuf);
641*0Sstevel@tonic-gate }
642*0Sstevel@tonic-gate 
643*0Sstevel@tonic-gate /*
644*0Sstevel@tonic-gate  * Process any options included by the client in the request packet.
645*0Sstevel@tonic-gate  * Return the size of the OACK reply packet built or 0 for no OACK reply.
646*0Sstevel@tonic-gate  */
647*0Sstevel@tonic-gate static int
648*0Sstevel@tonic-gate process_options(int opcode, char *opts, char *endopts)
649*0Sstevel@tonic-gate {
650*0Sstevel@tonic-gate 	char *cp, *optname, *optval, *ostr, *oackend;
651*0Sstevel@tonic-gate 	struct tftphdr *oackp;
652*0Sstevel@tonic-gate 	int i, errcode;
653*0Sstevel@tonic-gate 
654*0Sstevel@tonic-gate 	/*
655*0Sstevel@tonic-gate 	 * To continue to interoperate with broken TFTP clients, ignore
656*0Sstevel@tonic-gate 	 * null padding appended to requests which don't include options.
657*0Sstevel@tonic-gate 	 */
658*0Sstevel@tonic-gate 	cp = opts;
659*0Sstevel@tonic-gate 	while ((cp < endopts) && (*cp == '\0'))
660*0Sstevel@tonic-gate 		cp++;
661*0Sstevel@tonic-gate 	if (cp == endopts)
662*0Sstevel@tonic-gate 		return (0);
663*0Sstevel@tonic-gate 
664*0Sstevel@tonic-gate 	/*
665*0Sstevel@tonic-gate 	 * Construct an Option ACKnowledgement packet if any requested option
666*0Sstevel@tonic-gate 	 * is recognized.
667*0Sstevel@tonic-gate 	 */
668*0Sstevel@tonic-gate 	oackp = &oackbuf.hdr;
669*0Sstevel@tonic-gate 	oackend = oackbuf.data + sizeof (oackbuf.data);
670*0Sstevel@tonic-gate 	oackp->th_opcode = htons((ushort_t)OACK);
671*0Sstevel@tonic-gate 	cp = (char *)&oackp->th_stuff;
672*0Sstevel@tonic-gate 	while (opts < endopts) {
673*0Sstevel@tonic-gate 		optname = opts;
674*0Sstevel@tonic-gate 		if ((optval = next_field(optname, endopts)) == NULL) {
675*0Sstevel@tonic-gate 			nak(EOPTNEG);
676*0Sstevel@tonic-gate 			exit(1);
677*0Sstevel@tonic-gate 		}
678*0Sstevel@tonic-gate 		if ((opts = next_field(optval, endopts)) == NULL) {
679*0Sstevel@tonic-gate 			nak(EOPTNEG);
680*0Sstevel@tonic-gate 			exit(1);
681*0Sstevel@tonic-gate 		}
682*0Sstevel@tonic-gate 		for (i = 0; options[i].opt_name != NULL; i++) {
683*0Sstevel@tonic-gate 			if (strcasecmp(optname, options[i].opt_name) == 0)
684*0Sstevel@tonic-gate 				break;
685*0Sstevel@tonic-gate 		}
686*0Sstevel@tonic-gate 		if (options[i].opt_name != NULL) {
687*0Sstevel@tonic-gate 			ostr = options[i].opt_handler(opcode, optval, &errcode);
688*0Sstevel@tonic-gate 			if (ostr != NULL) {
689*0Sstevel@tonic-gate 				cp += strlcpy(cp, options[i].opt_name,
690*0Sstevel@tonic-gate 				    oackend - cp) + 1;
691*0Sstevel@tonic-gate 				if (cp <= oackend)
692*0Sstevel@tonic-gate 					cp += strlcpy(cp, ostr, oackend - cp)
693*0Sstevel@tonic-gate 					    + 1;
694*0Sstevel@tonic-gate 
695*0Sstevel@tonic-gate 				if (cp > oackend) {
696*0Sstevel@tonic-gate 					nak(EOPTNEG);
697*0Sstevel@tonic-gate 					exit(1);
698*0Sstevel@tonic-gate 				}
699*0Sstevel@tonic-gate 			} else if (errcode >= 0) {
700*0Sstevel@tonic-gate 				nak(errcode);
701*0Sstevel@tonic-gate 				exit(1);
702*0Sstevel@tonic-gate 			}
703*0Sstevel@tonic-gate 		}
704*0Sstevel@tonic-gate 	}
705*0Sstevel@tonic-gate 	if (cp != (char *)&oackp->th_stuff)
706*0Sstevel@tonic-gate 		return (cp - oackbuf.data);
707*0Sstevel@tonic-gate 	return (0);
708*0Sstevel@tonic-gate }
709*0Sstevel@tonic-gate 
710*0Sstevel@tonic-gate /*
711*0Sstevel@tonic-gate  * Handle access errors caused by client requests.
712*0Sstevel@tonic-gate  */
713*0Sstevel@tonic-gate 
714*0Sstevel@tonic-gate static void
715*0Sstevel@tonic-gate delay_exit(int ecode)
716*0Sstevel@tonic-gate {
717*0Sstevel@tonic-gate 	struct delay_info dinfo;
718*0Sstevel@tonic-gate 
719*0Sstevel@tonic-gate 	/*
720*0Sstevel@tonic-gate 	 * The most likely cause of an error here is that
721*0Sstevel@tonic-gate 	 * someone has broadcast an RRQ packet because s/he's
722*0Sstevel@tonic-gate 	 * trying to boot and doesn't know who the server is.
723*0Sstevel@tonic-gate 	 * Rather then sending an ERROR packet immediately, we
724*0Sstevel@tonic-gate 	 * wait a while so that the real server has a better chance
725*0Sstevel@tonic-gate 	 * of getting through (in case client has lousy Ethernet
726*0Sstevel@tonic-gate 	 * interface).  We write to a child that handles delayed
727*0Sstevel@tonic-gate 	 * ERROR packets to avoid delaying service to new
728*0Sstevel@tonic-gate 	 * requests.  Of course, we would rather just not answer
729*0Sstevel@tonic-gate 	 * RRQ packets that are broadcasted, but there's no way
730*0Sstevel@tonic-gate 	 * for a user process to determine this.
731*0Sstevel@tonic-gate 	 */
732*0Sstevel@tonic-gate 
733*0Sstevel@tonic-gate 	dinfo.timestamp = time(0);
734*0Sstevel@tonic-gate 
735*0Sstevel@tonic-gate 	/*
736*0Sstevel@tonic-gate 	 * If running in secure mode, we map all errors to EACCESS
737*0Sstevel@tonic-gate 	 * so that the client gets no information about which files
738*0Sstevel@tonic-gate 	 * or directories exist.
739*0Sstevel@tonic-gate 	 */
740*0Sstevel@tonic-gate 	if (securetftp)
741*0Sstevel@tonic-gate 		dinfo.ecode = EACCESS;
742*0Sstevel@tonic-gate 	else
743*0Sstevel@tonic-gate 		dinfo.ecode = ecode;
744*0Sstevel@tonic-gate 
745*0Sstevel@tonic-gate 	dinfo.from = from;
746*0Sstevel@tonic-gate 	if (write(delay_fd[1], &dinfo, sizeof (dinfo)) !=
747*0Sstevel@tonic-gate 	    sizeof (dinfo)) {
748*0Sstevel@tonic-gate 		syslog(LOG_ERR, "delayed write failed.");
749*0Sstevel@tonic-gate 		(void) kill(child, SIGKILL);
750*0Sstevel@tonic-gate 		exit(1);
751*0Sstevel@tonic-gate 	}
752*0Sstevel@tonic-gate 	exit(0);
753*0Sstevel@tonic-gate }
754*0Sstevel@tonic-gate 
755*0Sstevel@tonic-gate /*
756*0Sstevel@tonic-gate  * Handle initial connection protocol.
757*0Sstevel@tonic-gate  */
758*0Sstevel@tonic-gate static void
759*0Sstevel@tonic-gate tftp(struct tftphdr *tp, int size)
760*0Sstevel@tonic-gate {
761*0Sstevel@tonic-gate 	char *cp;
762*0Sstevel@tonic-gate 	int readmode, ecode;
763*0Sstevel@tonic-gate 	struct formats *pf;
764*0Sstevel@tonic-gate 	char *mode;
765*0Sstevel@tonic-gate 	int fd;
766*0Sstevel@tonic-gate 	static boolean_t firsttime = B_TRUE;
767*0Sstevel@tonic-gate 	int oacklen;
768*0Sstevel@tonic-gate 	struct stat statb;
769*0Sstevel@tonic-gate 
770*0Sstevel@tonic-gate 	readmode = (tp->th_opcode == RRQ);
771*0Sstevel@tonic-gate 	filename = (char *)&tp->th_stuff;
772*0Sstevel@tonic-gate 	mode = next_field(filename, &buf.data[size]);
773*0Sstevel@tonic-gate 	cp = (mode != NULL) ? next_field(mode, &buf.data[size]) : NULL;
774*0Sstevel@tonic-gate 	if (cp == NULL) {
775*0Sstevel@tonic-gate 		nak(EBADOP);
776*0Sstevel@tonic-gate 		exit(1);
777*0Sstevel@tonic-gate 	}
778*0Sstevel@tonic-gate 	if (debug && standalone) {
779*0Sstevel@tonic-gate 		(void) fprintf(stderr, "%s for %s %s ",
780*0Sstevel@tonic-gate 		    readmode ? "RRQ" : "WRQ", filename, mode);
781*0Sstevel@tonic-gate 		print_options(stderr, cp, size + buf.data - cp);
782*0Sstevel@tonic-gate 		(void) putc('\n', stderr);
783*0Sstevel@tonic-gate 	}
784*0Sstevel@tonic-gate 	for (pf = formats; pf->f_mode != NULL; pf++)
785*0Sstevel@tonic-gate 		if (strcasecmp(pf->f_mode, mode) == 0)
786*0Sstevel@tonic-gate 			break;
787*0Sstevel@tonic-gate 	if (pf->f_mode == NULL) {
788*0Sstevel@tonic-gate 		nak(EBADOP);
789*0Sstevel@tonic-gate 		exit(1);
790*0Sstevel@tonic-gate 	}
791*0Sstevel@tonic-gate 
792*0Sstevel@tonic-gate 	/*
793*0Sstevel@tonic-gate 	 * XXX fork a new process to handle this request before
794*0Sstevel@tonic-gate 	 * chroot(), otherwise the parent won't be able to create a
795*0Sstevel@tonic-gate 	 * new socket as that requires library access to system files
796*0Sstevel@tonic-gate 	 * and devices.
797*0Sstevel@tonic-gate 	 */
798*0Sstevel@tonic-gate 	(void) priv_set(PRIV_SET, PRIV_EFFECTIVE, PRIV_PROC_FORK, NULL);
799*0Sstevel@tonic-gate 	switch (fork()) {
800*0Sstevel@tonic-gate 	case -1:
801*0Sstevel@tonic-gate 		syslog(LOG_ERR, "fork (tftp): %m");
802*0Sstevel@tonic-gate 		(void) priv_set(PRIV_SET, PRIV_EFFECTIVE, NULL);
803*0Sstevel@tonic-gate 		return;
804*0Sstevel@tonic-gate 	case 0:
805*0Sstevel@tonic-gate 		(void) priv_set(PRIV_SET, PRIV_EFFECTIVE, NULL);
806*0Sstevel@tonic-gate 		break;
807*0Sstevel@tonic-gate 	default:
808*0Sstevel@tonic-gate 		(void) priv_set(PRIV_SET, PRIV_EFFECTIVE, NULL);
809*0Sstevel@tonic-gate 		return;
810*0Sstevel@tonic-gate 	}
811*0Sstevel@tonic-gate 
812*0Sstevel@tonic-gate 	/*
813*0Sstevel@tonic-gate 	 * Try to see if we can access the file.  The access can still
814*0Sstevel@tonic-gate 	 * fail later if we are running in secure mode because of
815*0Sstevel@tonic-gate 	 * the chroot() call.  We only want to execute the chroot()  once.
816*0Sstevel@tonic-gate 	 */
817*0Sstevel@tonic-gate 	if (securetftp && firsttime) {
818*0Sstevel@tonic-gate 		(void) priv_set(
819*0Sstevel@tonic-gate 		    PRIV_SET, PRIV_EFFECTIVE, PRIV_PROC_CHROOT, NULL);
820*0Sstevel@tonic-gate 		if (chroot(homedir) == -1) {
821*0Sstevel@tonic-gate 			syslog(LOG_ERR,
822*0Sstevel@tonic-gate 			    "tftpd: cannot chroot to directory %s: %m\n",
823*0Sstevel@tonic-gate 			    homedir);
824*0Sstevel@tonic-gate 			delay_exit(EACCESS);
825*0Sstevel@tonic-gate 		}
826*0Sstevel@tonic-gate 		else
827*0Sstevel@tonic-gate 		{
828*0Sstevel@tonic-gate 			firsttime = B_FALSE;
829*0Sstevel@tonic-gate 		}
830*0Sstevel@tonic-gate 		(void) priv_set(PRIV_SET, PRIV_EFFECTIVE, NULL);
831*0Sstevel@tonic-gate 		(void) chdir("/");  /* cd to  new root */
832*0Sstevel@tonic-gate 	}
833*0Sstevel@tonic-gate 	(void) priv_set(PRIV_SET, PRIV_ALLSETS, NULL);
834*0Sstevel@tonic-gate 
835*0Sstevel@tonic-gate 	ecode = (*pf->f_validate)(tp->th_opcode);
836*0Sstevel@tonic-gate 	if (ecode != 0)
837*0Sstevel@tonic-gate 		delay_exit(ecode);
838*0Sstevel@tonic-gate 
839*0Sstevel@tonic-gate 	/* we don't use the descriptors passed in to the parent */
840*0Sstevel@tonic-gate 	(void) close(STDIN_FILENO);
841*0Sstevel@tonic-gate 	(void) close(STDOUT_FILENO);
842*0Sstevel@tonic-gate 
843*0Sstevel@tonic-gate 	/*
844*0Sstevel@tonic-gate 	 * Try to open file as low-priv setuid/setgid.  Note that
845*0Sstevel@tonic-gate 	 * a chroot() has already been done.
846*0Sstevel@tonic-gate 	 */
847*0Sstevel@tonic-gate 	fd = open(filename,
848*0Sstevel@tonic-gate 	    (readmode ? O_RDONLY : (O_WRONLY|O_TRUNC)) | O_NONBLOCK);
849*0Sstevel@tonic-gate 	if ((fd < 0) || (fstat(fd, &statb) < 0))
850*0Sstevel@tonic-gate 		delay_exit((errno == ENOENT) ? ENOTFOUND : EACCESS);
851*0Sstevel@tonic-gate 
852*0Sstevel@tonic-gate 	if (((statb.st_mode & ((readmode) ? S_IROTH : S_IWOTH)) == 0) ||
853*0Sstevel@tonic-gate 	    ((statb.st_mode & S_IFMT) != S_IFREG))
854*0Sstevel@tonic-gate 		delay_exit(EACCESS);
855*0Sstevel@tonic-gate 
856*0Sstevel@tonic-gate 	file = fdopen(fd, readmode ? "r" : "w");
857*0Sstevel@tonic-gate 	if (file == NULL)
858*0Sstevel@tonic-gate 		delay_exit(errno + 100);
859*0Sstevel@tonic-gate 
860*0Sstevel@tonic-gate 	/* Don't know the size of transfers which involve conversion */
861*0Sstevel@tonic-gate 	tsize_set = (readmode && (pf->f_convert == 0));
862*0Sstevel@tonic-gate 	if (tsize_set)
863*0Sstevel@tonic-gate 		tsize = statb.st_size;
864*0Sstevel@tonic-gate 
865*0Sstevel@tonic-gate 	/* Deal with any options sent by the client */
866*0Sstevel@tonic-gate 	oacklen = process_options(tp->th_opcode, cp, buf.data + size);
867*0Sstevel@tonic-gate 
868*0Sstevel@tonic-gate 	if (tp->th_opcode == WRQ)
869*0Sstevel@tonic-gate 		(*pf->f_recv)(pf, oacklen);
870*0Sstevel@tonic-gate 	else
871*0Sstevel@tonic-gate 		(*pf->f_send)(pf, oacklen);
872*0Sstevel@tonic-gate 
873*0Sstevel@tonic-gate 	exit(0);
874*0Sstevel@tonic-gate }
875*0Sstevel@tonic-gate 
876*0Sstevel@tonic-gate /*
877*0Sstevel@tonic-gate  *	Maybe map filename into another one.
878*0Sstevel@tonic-gate  *
879*0Sstevel@tonic-gate  *	For PNP, we get TFTP boot requests for filenames like
880*0Sstevel@tonic-gate  *	<Unknown Hex IP Addr>.<Architecture Name>.   We must
881*0Sstevel@tonic-gate  *	map these to 'pnp.<Architecture Name>'.  Note that
882*0Sstevel@tonic-gate  *	uppercase is mapped to lowercase in the architecture names.
883*0Sstevel@tonic-gate  *
884*0Sstevel@tonic-gate  *	For names <Hex IP Addr> there are two cases.  First,
885*0Sstevel@tonic-gate  *	it may be a buggy prom that omits the architecture code.
886*0Sstevel@tonic-gate  *	So first check if <Hex IP Addr>.<arch> is on the filesystem.
887*0Sstevel@tonic-gate  *	Second, this is how most Sun3s work; assume <arch> is sun3.
888*0Sstevel@tonic-gate  */
889*0Sstevel@tonic-gate 
890*0Sstevel@tonic-gate static char *
891*0Sstevel@tonic-gate pnp_check(char *origname)
892*0Sstevel@tonic-gate {
893*0Sstevel@tonic-gate 	static char buf [MAXNAMLEN + 1];
894*0Sstevel@tonic-gate 	char *arch, *s, *bufend;
895*0Sstevel@tonic-gate 	in_addr_t ipaddr;
896*0Sstevel@tonic-gate 	int len = (origname ? strlen(origname) : 0);
897*0Sstevel@tonic-gate 	DIR *dir;
898*0Sstevel@tonic-gate 	struct dirent *dp;
899*0Sstevel@tonic-gate 
900*0Sstevel@tonic-gate 	if (securetftp || disable_pnp || len < 8 || len > 14)
901*0Sstevel@tonic-gate 		return (NULL);
902*0Sstevel@tonic-gate 
903*0Sstevel@tonic-gate 	/*
904*0Sstevel@tonic-gate 	 * XXX see if this cable allows pnp; if not, return NULL
905*0Sstevel@tonic-gate 	 * Requires YP support for determining this!
906*0Sstevel@tonic-gate 	 */
907*0Sstevel@tonic-gate 
908*0Sstevel@tonic-gate 	ipaddr = htonl(strtol(origname, &arch, 16));
909*0Sstevel@tonic-gate 	if ((arch == NULL) || (len > 8 && *arch != '.'))
910*0Sstevel@tonic-gate 		return (NULL);
911*0Sstevel@tonic-gate 	if (len == 8)
912*0Sstevel@tonic-gate 		arch = "SUN3";
913*0Sstevel@tonic-gate 	else
914*0Sstevel@tonic-gate 		arch++;
915*0Sstevel@tonic-gate 
916*0Sstevel@tonic-gate 	/*
917*0Sstevel@tonic-gate 	 * Allow <Hex IP Addr>* filename request to to be
918*0Sstevel@tonic-gate 	 * satisfied by <Hex IP Addr><Any Suffix> rather
919*0Sstevel@tonic-gate 	 * than enforcing this to be Sun3 systems.  Also serves
920*0Sstevel@tonic-gate 	 * to make case of suffix a don't-care.
921*0Sstevel@tonic-gate 	 */
922*0Sstevel@tonic-gate 	if ((dir = opendir(homedir)) == NULL)
923*0Sstevel@tonic-gate 		return (NULL);
924*0Sstevel@tonic-gate 	while ((dp = readdir(dir)) != NULL) {
925*0Sstevel@tonic-gate 		if (strncmp(origname, dp->d_name, 8) == 0) {
926*0Sstevel@tonic-gate 			(void) strlcpy(buf, dp->d_name, sizeof (buf));
927*0Sstevel@tonic-gate 			(void) closedir(dir);
928*0Sstevel@tonic-gate 			return (buf);
929*0Sstevel@tonic-gate 		}
930*0Sstevel@tonic-gate 	}
931*0Sstevel@tonic-gate 	(void) closedir(dir);
932*0Sstevel@tonic-gate 
933*0Sstevel@tonic-gate 	/*
934*0Sstevel@tonic-gate 	 * XXX maybe call YP master for most current data iff
935*0Sstevel@tonic-gate 	 * pnp is enabled.
936*0Sstevel@tonic-gate 	 */
937*0Sstevel@tonic-gate 
938*0Sstevel@tonic-gate 	/*
939*0Sstevel@tonic-gate 	 * only do mapping PNP boot file name for machines that
940*0Sstevel@tonic-gate 	 * are not in the hosts database.
941*0Sstevel@tonic-gate 	 */
942*0Sstevel@tonic-gate 	if (gethostbyaddr((char *)&ipaddr, sizeof (ipaddr), AF_INET) != NULL)
943*0Sstevel@tonic-gate 		return (NULL);
944*0Sstevel@tonic-gate 
945*0Sstevel@tonic-gate 	s = buf + strlcpy(buf, "pnp.", sizeof (buf));
946*0Sstevel@tonic-gate 	bufend = &buf[sizeof (buf) - 1];
947*0Sstevel@tonic-gate 	while ((*arch != '\0') && (s < bufend))
948*0Sstevel@tonic-gate 		*s++ = tolower (*arch++);
949*0Sstevel@tonic-gate 	*s = '\0';
950*0Sstevel@tonic-gate 	return (buf);
951*0Sstevel@tonic-gate }
952*0Sstevel@tonic-gate 
953*0Sstevel@tonic-gate 
954*0Sstevel@tonic-gate /*
955*0Sstevel@tonic-gate  * Try to validate filename. If the filename doesn't exist try PNP mapping.
956*0Sstevel@tonic-gate  */
957*0Sstevel@tonic-gate static int
958*0Sstevel@tonic-gate validate_filename(int mode)
959*0Sstevel@tonic-gate {
960*0Sstevel@tonic-gate 	struct stat stbuf;
961*0Sstevel@tonic-gate 	char *origfile;
962*0Sstevel@tonic-gate 
963*0Sstevel@tonic-gate 	if (stat(filename, &stbuf) < 0) {
964*0Sstevel@tonic-gate 		if (errno != ENOENT)
965*0Sstevel@tonic-gate 			return (EACCESS);
966*0Sstevel@tonic-gate 		if (mode == WRQ)
967*0Sstevel@tonic-gate 			return (ENOTFOUND);
968*0Sstevel@tonic-gate 
969*0Sstevel@tonic-gate 		/* try to map requested filename into a pnp filename */
970*0Sstevel@tonic-gate 		origfile = filename;
971*0Sstevel@tonic-gate 		filename = pnp_check(origfile);
972*0Sstevel@tonic-gate 		if (filename == NULL)
973*0Sstevel@tonic-gate 			return (ENOTFOUND);
974*0Sstevel@tonic-gate 
975*0Sstevel@tonic-gate 		if (stat(filename, &stbuf) < 0)
976*0Sstevel@tonic-gate 			return (errno == ENOENT ? ENOTFOUND : EACCESS);
977*0Sstevel@tonic-gate 		syslog(LOG_NOTICE, "%s -> %s\n", origfile, filename);
978*0Sstevel@tonic-gate 	}
979*0Sstevel@tonic-gate 
980*0Sstevel@tonic-gate 	return (0);
981*0Sstevel@tonic-gate }
982*0Sstevel@tonic-gate 
983*0Sstevel@tonic-gate /* ARGSUSED */
984*0Sstevel@tonic-gate static void
985*0Sstevel@tonic-gate timer(int signum)
986*0Sstevel@tonic-gate {
987*0Sstevel@tonic-gate 	timeout += rexmtval;
988*0Sstevel@tonic-gate 	if (timeout >= maxtimeout)
989*0Sstevel@tonic-gate 		exit(1);
990*0Sstevel@tonic-gate 	siglongjmp(timeoutbuf, 1);
991*0Sstevel@tonic-gate }
992*0Sstevel@tonic-gate 
993*0Sstevel@tonic-gate /*
994*0Sstevel@tonic-gate  * Send the requested file.
995*0Sstevel@tonic-gate  */
996*0Sstevel@tonic-gate static void
997*0Sstevel@tonic-gate tftpd_sendfile(struct formats *pf, int oacklen)
998*0Sstevel@tonic-gate {
999*0Sstevel@tonic-gate 	struct tftphdr *dp;
1000*0Sstevel@tonic-gate 	volatile int block = 1;
1001*0Sstevel@tonic-gate 	int size, n, serrno;
1002*0Sstevel@tonic-gate 
1003*0Sstevel@tonic-gate 	if (oacklen != 0) {
1004*0Sstevel@tonic-gate 		(void) sigset(SIGALRM, timer);
1005*0Sstevel@tonic-gate 		timeout = 0;
1006*0Sstevel@tonic-gate 		(void) sigsetjmp(timeoutbuf, 1);
1007*0Sstevel@tonic-gate 		if (debug && standalone) {
1008*0Sstevel@tonic-gate 			(void) fputs("Sending OACK ", stderr);
1009*0Sstevel@tonic-gate 			print_options(stderr, (char *)&oackbuf.hdr.th_stuff,
1010*0Sstevel@tonic-gate 			    oacklen - 2);
1011*0Sstevel@tonic-gate 			(void) putc('\n', stderr);
1012*0Sstevel@tonic-gate 		}
1013*0Sstevel@tonic-gate 		if (sendto(peer, &oackbuf, oacklen, 0,
1014*0Sstevel@tonic-gate 		    (struct sockaddr *)&from, fromplen) != oacklen) {
1015*0Sstevel@tonic-gate 			if (debug && standalone) {
1016*0Sstevel@tonic-gate 				serrno = errno;
1017*0Sstevel@tonic-gate 				perror("sendto (oack)");
1018*0Sstevel@tonic-gate 				errno = serrno;
1019*0Sstevel@tonic-gate 			}
1020*0Sstevel@tonic-gate 			SYSLOG_MSG("sendto (oack): %m");
1021*0Sstevel@tonic-gate 			goto abort;
1022*0Sstevel@tonic-gate 		}
1023*0Sstevel@tonic-gate 		(void) alarm(rexmtval); /* read the ack */
1024*0Sstevel@tonic-gate 		for (;;) {
1025*0Sstevel@tonic-gate 			(void) sigrelse(SIGALRM);
1026*0Sstevel@tonic-gate 			n = recv(peer, &ackbuf, sizeof (ackbuf), 0);
1027*0Sstevel@tonic-gate 			(void) sighold(SIGALRM);
1028*0Sstevel@tonic-gate 			if (n < 0) {
1029*0Sstevel@tonic-gate 				if (errno == EINTR)
1030*0Sstevel@tonic-gate 					continue;
1031*0Sstevel@tonic-gate 				serrno = errno;
1032*0Sstevel@tonic-gate 				SYSLOG_MSG("recv (ack): %m");
1033*0Sstevel@tonic-gate 				if (debug && standalone) {
1034*0Sstevel@tonic-gate 					errno = serrno;
1035*0Sstevel@tonic-gate 					perror("recv (ack)");
1036*0Sstevel@tonic-gate 				}
1037*0Sstevel@tonic-gate 				goto abort;
1038*0Sstevel@tonic-gate 			}
1039*0Sstevel@tonic-gate 			ackbuf.tb_hdr.th_opcode =
1040*0Sstevel@tonic-gate 			    ntohs((ushort_t)ackbuf.tb_hdr.th_opcode);
1041*0Sstevel@tonic-gate 			ackbuf.tb_hdr.th_block =
1042*0Sstevel@tonic-gate 			    ntohs((ushort_t)ackbuf.tb_hdr.th_block);
1043*0Sstevel@tonic-gate 
1044*0Sstevel@tonic-gate 			if (ackbuf.tb_hdr.th_opcode == ERROR) {
1045*0Sstevel@tonic-gate 				if (debug && standalone) {
1046*0Sstevel@tonic-gate 					(void) fprintf(stderr,
1047*0Sstevel@tonic-gate 					    "received ERROR %d",
1048*0Sstevel@tonic-gate 					    ackbuf.tb_hdr.th_code);
1049*0Sstevel@tonic-gate 					if (n > 4)
1050*0Sstevel@tonic-gate 						(void) fprintf(stderr,
1051*0Sstevel@tonic-gate 						    " %.*s", n - 4,
1052*0Sstevel@tonic-gate 						    ackbuf.tb_hdr.th_msg);
1053*0Sstevel@tonic-gate 					(void) putc('\n', stderr);
1054*0Sstevel@tonic-gate 				}
1055*0Sstevel@tonic-gate 				goto abort;
1056*0Sstevel@tonic-gate 			}
1057*0Sstevel@tonic-gate 
1058*0Sstevel@tonic-gate 			if (ackbuf.tb_hdr.th_opcode == ACK) {
1059*0Sstevel@tonic-gate 				if (debug && standalone)
1060*0Sstevel@tonic-gate 					(void) fprintf(stderr,
1061*0Sstevel@tonic-gate 					    "received ACK for block %d\n",
1062*0Sstevel@tonic-gate 					    ackbuf.tb_hdr.th_block);
1063*0Sstevel@tonic-gate 				if (ackbuf.tb_hdr.th_block == 0)
1064*0Sstevel@tonic-gate 					break;
1065*0Sstevel@tonic-gate 				/*
1066*0Sstevel@tonic-gate 				 * Don't resend the OACK, avoids getting stuck
1067*0Sstevel@tonic-gate 				 * in an OACK/ACK loop if the client keeps
1068*0Sstevel@tonic-gate 				 * replying with a bad ACK. Client will either
1069*0Sstevel@tonic-gate 				 * send a good ACK or timeout sending bad ones.
1070*0Sstevel@tonic-gate 				 */
1071*0Sstevel@tonic-gate 			}
1072*0Sstevel@tonic-gate 		}
1073*0Sstevel@tonic-gate 		cancel_alarm();
1074*0Sstevel@tonic-gate 	}
1075*0Sstevel@tonic-gate 	dp = r_init();
1076*0Sstevel@tonic-gate 	do {
1077*0Sstevel@tonic-gate 		(void) sigset(SIGALRM, timer);
1078*0Sstevel@tonic-gate 		size = readit(file, &dp, pf->f_convert);
1079*0Sstevel@tonic-gate 		if (size < 0) {
1080*0Sstevel@tonic-gate 			nak(errno + 100);
1081*0Sstevel@tonic-gate 			goto abort;
1082*0Sstevel@tonic-gate 		}
1083*0Sstevel@tonic-gate 		dp->th_opcode = htons((ushort_t)DATA);
1084*0Sstevel@tonic-gate 		dp->th_block = htons((ushort_t)block);
1085*0Sstevel@tonic-gate 		timeout = 0;
1086*0Sstevel@tonic-gate 		(void) sigsetjmp(timeoutbuf, 1);
1087*0Sstevel@tonic-gate 		if (debug && standalone)
1088*0Sstevel@tonic-gate 			(void) fprintf(stderr, "Sending DATA block %d\n",
1089*0Sstevel@tonic-gate 			    block);
1090*0Sstevel@tonic-gate 		if (sendto(peer, dp, size + 4, 0,
1091*0Sstevel@tonic-gate 		    (struct sockaddr *)&from,  fromplen) != size + 4) {
1092*0Sstevel@tonic-gate 			if (debug && standalone) {
1093*0Sstevel@tonic-gate 				serrno = errno;
1094*0Sstevel@tonic-gate 				perror("sendto (data)");
1095*0Sstevel@tonic-gate 				errno = serrno;
1096*0Sstevel@tonic-gate 			}
1097*0Sstevel@tonic-gate 			SYSLOG_MSG("sendto (data): %m");
1098*0Sstevel@tonic-gate 			goto abort;
1099*0Sstevel@tonic-gate 		}
1100*0Sstevel@tonic-gate 		read_ahead(file, pf->f_convert);
1101*0Sstevel@tonic-gate 		(void) alarm(rexmtval); /* read the ack */
1102*0Sstevel@tonic-gate 		for (;;) {
1103*0Sstevel@tonic-gate 			(void) sigrelse(SIGALRM);
1104*0Sstevel@tonic-gate 			n = recv(peer, &ackbuf, sizeof (ackbuf), 0);
1105*0Sstevel@tonic-gate 			(void) sighold(SIGALRM);
1106*0Sstevel@tonic-gate 			if (n < 0) {
1107*0Sstevel@tonic-gate 				if (errno == EINTR)
1108*0Sstevel@tonic-gate 					continue;
1109*0Sstevel@tonic-gate 				serrno = errno;
1110*0Sstevel@tonic-gate 				SYSLOG_MSG("recv (ack): %m");
1111*0Sstevel@tonic-gate 				if (debug && standalone) {
1112*0Sstevel@tonic-gate 					errno = serrno;
1113*0Sstevel@tonic-gate 					perror("recv (ack)");
1114*0Sstevel@tonic-gate 				}
1115*0Sstevel@tonic-gate 				goto abort;
1116*0Sstevel@tonic-gate 			}
1117*0Sstevel@tonic-gate 			ackbuf.tb_hdr.th_opcode =
1118*0Sstevel@tonic-gate 			    ntohs((ushort_t)ackbuf.tb_hdr.th_opcode);
1119*0Sstevel@tonic-gate 			ackbuf.tb_hdr.th_block =
1120*0Sstevel@tonic-gate 			    ntohs((ushort_t)ackbuf.tb_hdr.th_block);
1121*0Sstevel@tonic-gate 
1122*0Sstevel@tonic-gate 			if (ackbuf.tb_hdr.th_opcode == ERROR) {
1123*0Sstevel@tonic-gate 				if (debug && standalone) {
1124*0Sstevel@tonic-gate 					(void) fprintf(stderr,
1125*0Sstevel@tonic-gate 					    "received ERROR %d",
1126*0Sstevel@tonic-gate 					    ackbuf.tb_hdr.th_code);
1127*0Sstevel@tonic-gate 					if (n > 4)
1128*0Sstevel@tonic-gate 						(void) fprintf(stderr,
1129*0Sstevel@tonic-gate 						    " %.*s", n - 4,
1130*0Sstevel@tonic-gate 						    ackbuf.tb_hdr.th_msg);
1131*0Sstevel@tonic-gate 					(void) putc('\n', stderr);
1132*0Sstevel@tonic-gate 				}
1133*0Sstevel@tonic-gate 				goto abort;
1134*0Sstevel@tonic-gate 			}
1135*0Sstevel@tonic-gate 
1136*0Sstevel@tonic-gate 			if (ackbuf.tb_hdr.th_opcode == ACK) {
1137*0Sstevel@tonic-gate 				if (debug && standalone)
1138*0Sstevel@tonic-gate 					(void) fprintf(stderr,
1139*0Sstevel@tonic-gate 						"received ACK for block %d\n",
1140*0Sstevel@tonic-gate 						ackbuf.tb_hdr.th_block);
1141*0Sstevel@tonic-gate 				if (ackbuf.tb_hdr.th_block == block) {
1142*0Sstevel@tonic-gate 					break;
1143*0Sstevel@tonic-gate 				}
1144*0Sstevel@tonic-gate 				/*
1145*0Sstevel@tonic-gate 				 * Never resend the current DATA packet on
1146*0Sstevel@tonic-gate 				 * receipt of a duplicate ACK, doing so would
1147*0Sstevel@tonic-gate 				 * cause the "Sorcerer's Apprentice Syndrome".
1148*0Sstevel@tonic-gate 				 */
1149*0Sstevel@tonic-gate 			}
1150*0Sstevel@tonic-gate 		}
1151*0Sstevel@tonic-gate 		cancel_alarm();
1152*0Sstevel@tonic-gate 		block++;
1153*0Sstevel@tonic-gate 	} while (size == blocksize);
1154*0Sstevel@tonic-gate 
1155*0Sstevel@tonic-gate abort:
1156*0Sstevel@tonic-gate 	cancel_alarm();
1157*0Sstevel@tonic-gate 	(void) fclose(file);
1158*0Sstevel@tonic-gate }
1159*0Sstevel@tonic-gate 
1160*0Sstevel@tonic-gate /* ARGSUSED */
1161*0Sstevel@tonic-gate static void
1162*0Sstevel@tonic-gate justquit(int signum)
1163*0Sstevel@tonic-gate {
1164*0Sstevel@tonic-gate 	exit(0);
1165*0Sstevel@tonic-gate }
1166*0Sstevel@tonic-gate 
1167*0Sstevel@tonic-gate /*
1168*0Sstevel@tonic-gate  * Receive a file.
1169*0Sstevel@tonic-gate  */
1170*0Sstevel@tonic-gate static void
1171*0Sstevel@tonic-gate tftpd_recvfile(struct formats *pf, int oacklen)
1172*0Sstevel@tonic-gate {
1173*0Sstevel@tonic-gate 	struct tftphdr *dp;
1174*0Sstevel@tonic-gate 	struct tftphdr *ap;    /* ack buffer */
1175*0Sstevel@tonic-gate 	int block = 0, n, size, acklen, serrno;
1176*0Sstevel@tonic-gate 
1177*0Sstevel@tonic-gate 	dp = w_init();
1178*0Sstevel@tonic-gate 	ap = &ackbuf.tb_hdr;
1179*0Sstevel@tonic-gate 	do {
1180*0Sstevel@tonic-gate 		(void) sigset(SIGALRM, timer);
1181*0Sstevel@tonic-gate 		timeout = 0;
1182*0Sstevel@tonic-gate 		if (oacklen == 0) {
1183*0Sstevel@tonic-gate 			ap->th_opcode = htons((ushort_t)ACK);
1184*0Sstevel@tonic-gate 			ap->th_block = htons((ushort_t)block);
1185*0Sstevel@tonic-gate 			acklen = 4;
1186*0Sstevel@tonic-gate 		} else {
1187*0Sstevel@tonic-gate 			/* copy OACK packet to the ack buffer ready to send */
1188*0Sstevel@tonic-gate 			(void) memcpy(&ackbuf, &oackbuf, oacklen);
1189*0Sstevel@tonic-gate 			acklen = oacklen;
1190*0Sstevel@tonic-gate 			oacklen = 0;
1191*0Sstevel@tonic-gate 		}
1192*0Sstevel@tonic-gate 		block++;
1193*0Sstevel@tonic-gate 		(void) sigsetjmp(timeoutbuf, 1);
1194*0Sstevel@tonic-gate send_ack:
1195*0Sstevel@tonic-gate 		if (debug && standalone) {
1196*0Sstevel@tonic-gate 			if (ap->th_opcode == htons((ushort_t)ACK)) {
1197*0Sstevel@tonic-gate 				(void) fprintf(stderr,
1198*0Sstevel@tonic-gate 				    "Sending ACK for block %d\n", block - 1);
1199*0Sstevel@tonic-gate 			} else {
1200*0Sstevel@tonic-gate 				(void) fprintf(stderr, "Sending OACK ");
1201*0Sstevel@tonic-gate 				print_options(stderr, (char *)&ap->th_stuff,
1202*0Sstevel@tonic-gate 				    acklen - 2);
1203*0Sstevel@tonic-gate 				(void) putc('\n', stderr);
1204*0Sstevel@tonic-gate 			}
1205*0Sstevel@tonic-gate 		}
1206*0Sstevel@tonic-gate 		if (sendto(peer, &ackbuf, acklen, 0, (struct sockaddr *)&from,
1207*0Sstevel@tonic-gate 		    fromplen) != acklen) {
1208*0Sstevel@tonic-gate 			if (ap->th_opcode == htons((ushort_t)ACK)) {
1209*0Sstevel@tonic-gate 				if (debug && standalone) {
1210*0Sstevel@tonic-gate 					serrno = errno;
1211*0Sstevel@tonic-gate 					perror("sendto (ack)");
1212*0Sstevel@tonic-gate 					errno = serrno;
1213*0Sstevel@tonic-gate 				}
1214*0Sstevel@tonic-gate 				syslog(LOG_ERR, "sendto (ack): %m\n");
1215*0Sstevel@tonic-gate 			} else {
1216*0Sstevel@tonic-gate 				if (debug && standalone) {
1217*0Sstevel@tonic-gate 					serrno = errno;
1218*0Sstevel@tonic-gate 					perror("sendto (oack)");
1219*0Sstevel@tonic-gate 					errno = serrno;
1220*0Sstevel@tonic-gate 				}
1221*0Sstevel@tonic-gate 				syslog(LOG_ERR, "sendto (oack): %m\n");
1222*0Sstevel@tonic-gate 			}
1223*0Sstevel@tonic-gate 			goto abort;
1224*0Sstevel@tonic-gate 		}
1225*0Sstevel@tonic-gate 		if (write_behind(file, pf->f_convert) < 0) {
1226*0Sstevel@tonic-gate 			nak(errno + 100);
1227*0Sstevel@tonic-gate 			goto abort;
1228*0Sstevel@tonic-gate 		}
1229*0Sstevel@tonic-gate 		(void) alarm(rexmtval);
1230*0Sstevel@tonic-gate 		for (;;) {
1231*0Sstevel@tonic-gate 			(void) sigrelse(SIGALRM);
1232*0Sstevel@tonic-gate 			n = recv(peer, dp, blocksize + 4, 0);
1233*0Sstevel@tonic-gate 			(void) sighold(SIGALRM);
1234*0Sstevel@tonic-gate 			if (n < 0) { /* really? */
1235*0Sstevel@tonic-gate 				if (errno == EINTR)
1236*0Sstevel@tonic-gate 					continue;
1237*0Sstevel@tonic-gate 				syslog(LOG_ERR, "recv (data): %m");
1238*0Sstevel@tonic-gate 				goto abort;
1239*0Sstevel@tonic-gate 			}
1240*0Sstevel@tonic-gate 			dp->th_opcode = ntohs((ushort_t)dp->th_opcode);
1241*0Sstevel@tonic-gate 			dp->th_block = ntohs((ushort_t)dp->th_block);
1242*0Sstevel@tonic-gate 			if (dp->th_opcode == ERROR) {
1243*0Sstevel@tonic-gate 				cancel_alarm();
1244*0Sstevel@tonic-gate 				if (debug && standalone) {
1245*0Sstevel@tonic-gate 					(void) fprintf(stderr,
1246*0Sstevel@tonic-gate 					    "received ERROR %d", dp->th_code);
1247*0Sstevel@tonic-gate 					if (n > 4)
1248*0Sstevel@tonic-gate 						(void) fprintf(stderr,
1249*0Sstevel@tonic-gate 						    " %.*s", n - 4, dp->th_msg);
1250*0Sstevel@tonic-gate 					(void) putc('\n', stderr);
1251*0Sstevel@tonic-gate 				}
1252*0Sstevel@tonic-gate 				return;
1253*0Sstevel@tonic-gate 			}
1254*0Sstevel@tonic-gate 			if (dp->th_opcode == DATA) {
1255*0Sstevel@tonic-gate 				if (debug && standalone)
1256*0Sstevel@tonic-gate 					(void) fprintf(stderr,
1257*0Sstevel@tonic-gate 						"Received DATA block %d\n",
1258*0Sstevel@tonic-gate 						dp->th_block);
1259*0Sstevel@tonic-gate 				if (dp->th_block == block) {
1260*0Sstevel@tonic-gate 					break;   /* normal */
1261*0Sstevel@tonic-gate 				}
1262*0Sstevel@tonic-gate 				/* Re-synchronize with the other side */
1263*0Sstevel@tonic-gate 				if (synchnet(peer) < 0) {
1264*0Sstevel@tonic-gate 					nak(errno + 100);
1265*0Sstevel@tonic-gate 					goto abort;
1266*0Sstevel@tonic-gate 				}
1267*0Sstevel@tonic-gate 				if (dp->th_block == (block-1))
1268*0Sstevel@tonic-gate 					goto send_ack; /* rexmit */
1269*0Sstevel@tonic-gate 			}
1270*0Sstevel@tonic-gate 		}
1271*0Sstevel@tonic-gate 		cancel_alarm();
1272*0Sstevel@tonic-gate 		/*  size = write(file, dp->th_data, n - 4); */
1273*0Sstevel@tonic-gate 		size = writeit(file, &dp, n - 4, pf->f_convert);
1274*0Sstevel@tonic-gate 		if (size != (n - 4)) {
1275*0Sstevel@tonic-gate 			nak((size < 0) ? (errno + 100) : ENOSPACE);
1276*0Sstevel@tonic-gate 			goto abort;
1277*0Sstevel@tonic-gate 		}
1278*0Sstevel@tonic-gate 	} while (size == blocksize);
1279*0Sstevel@tonic-gate 	if (write_behind(file, pf->f_convert) < 0) {
1280*0Sstevel@tonic-gate 		nak(errno + 100);
1281*0Sstevel@tonic-gate 		goto abort;
1282*0Sstevel@tonic-gate 	}
1283*0Sstevel@tonic-gate 	n = fclose(file);	/* close data file */
1284*0Sstevel@tonic-gate 	file = NULL;
1285*0Sstevel@tonic-gate 	if (n == EOF) {
1286*0Sstevel@tonic-gate 		nak(errno + 100);
1287*0Sstevel@tonic-gate 		goto abort;
1288*0Sstevel@tonic-gate 	}
1289*0Sstevel@tonic-gate 
1290*0Sstevel@tonic-gate 	ap->th_opcode = htons((ushort_t)ACK);    /* send the "final" ack */
1291*0Sstevel@tonic-gate 	ap->th_block = htons((ushort_t)(block));
1292*0Sstevel@tonic-gate 	if (debug && standalone)
1293*0Sstevel@tonic-gate 		(void) fprintf(stderr, "Sending ACK for block %d\n", block);
1294*0Sstevel@tonic-gate 	if (sendto(peer, &ackbuf, 4, 0, (struct sockaddr *)&from,
1295*0Sstevel@tonic-gate 	    fromplen) == -1) {
1296*0Sstevel@tonic-gate 		if (debug && standalone)
1297*0Sstevel@tonic-gate 			perror("sendto (ack)");
1298*0Sstevel@tonic-gate 	}
1299*0Sstevel@tonic-gate 	(void) sigset(SIGALRM, justquit); /* just quit on timeout */
1300*0Sstevel@tonic-gate 	(void) alarm(rexmtval);
1301*0Sstevel@tonic-gate 	/* normally times out and quits */
1302*0Sstevel@tonic-gate 	n = recv(peer, dp, blocksize + 4, 0);
1303*0Sstevel@tonic-gate 	(void) alarm(0);
1304*0Sstevel@tonic-gate 	dp->th_opcode = ntohs((ushort_t)dp->th_opcode);
1305*0Sstevel@tonic-gate 	dp->th_block = ntohs((ushort_t)dp->th_block);
1306*0Sstevel@tonic-gate 	if (n >= 4 &&		/* if read some data */
1307*0Sstevel@tonic-gate 	    dp->th_opcode == DATA && /* and got a data block */
1308*0Sstevel@tonic-gate 	    block == dp->th_block) {	/* then my last ack was lost */
1309*0Sstevel@tonic-gate 		if (debug && standalone) {
1310*0Sstevel@tonic-gate 			(void) fprintf(stderr, "Sending ACK for block %d\n",
1311*0Sstevel@tonic-gate 			    block);
1312*0Sstevel@tonic-gate 		}
1313*0Sstevel@tonic-gate 		/* resend final ack */
1314*0Sstevel@tonic-gate 		if (sendto(peer, &ackbuf, 4, 0, (struct sockaddr *)&from,
1315*0Sstevel@tonic-gate 		    fromplen) == -1) {
1316*0Sstevel@tonic-gate 			if (debug && standalone)
1317*0Sstevel@tonic-gate 				perror("sendto (last ack)");
1318*0Sstevel@tonic-gate 		}
1319*0Sstevel@tonic-gate 	}
1320*0Sstevel@tonic-gate 
1321*0Sstevel@tonic-gate abort:
1322*0Sstevel@tonic-gate 	cancel_alarm();
1323*0Sstevel@tonic-gate 	if (file != NULL)
1324*0Sstevel@tonic-gate 		(void) fclose(file);
1325*0Sstevel@tonic-gate }
1326*0Sstevel@tonic-gate 
1327*0Sstevel@tonic-gate /*
1328*0Sstevel@tonic-gate  * Send a nak packet (error message).
1329*0Sstevel@tonic-gate  * Error code passed in is one of the
1330*0Sstevel@tonic-gate  * standard TFTP codes, or a UNIX errno
1331*0Sstevel@tonic-gate  * offset by 100.
1332*0Sstevel@tonic-gate  * Handles connected as well as unconnected peer.
1333*0Sstevel@tonic-gate  */
1334*0Sstevel@tonic-gate static void
1335*0Sstevel@tonic-gate nak(int error)
1336*0Sstevel@tonic-gate {
1337*0Sstevel@tonic-gate 	struct tftphdr *tp;
1338*0Sstevel@tonic-gate 	int length;
1339*0Sstevel@tonic-gate 	struct errmsg *pe;
1340*0Sstevel@tonic-gate 	int ret;
1341*0Sstevel@tonic-gate 
1342*0Sstevel@tonic-gate 	tp = &buf.hdr;
1343*0Sstevel@tonic-gate 	tp->th_opcode = htons((ushort_t)ERROR);
1344*0Sstevel@tonic-gate 	tp->th_code = htons((ushort_t)error);
1345*0Sstevel@tonic-gate 	for (pe = errmsgs; pe->e_code >= 0; pe++)
1346*0Sstevel@tonic-gate 		if (pe->e_code == error)
1347*0Sstevel@tonic-gate 			break;
1348*0Sstevel@tonic-gate 	if (pe->e_code < 0) {
1349*0Sstevel@tonic-gate 		pe->e_msg = strerror(error - 100);
1350*0Sstevel@tonic-gate 		tp->th_code = EUNDEF;   /* set 'undef' errorcode */
1351*0Sstevel@tonic-gate 	}
1352*0Sstevel@tonic-gate 	(void) strlcpy(tp->th_msg, (pe->e_msg != NULL) ? pe->e_msg : "UNKNOWN",
1353*0Sstevel@tonic-gate 	    sizeof (buf) - sizeof (struct tftphdr));
1354*0Sstevel@tonic-gate 	length = strlen(tp->th_msg);
1355*0Sstevel@tonic-gate 	length += sizeof (struct tftphdr);
1356*0Sstevel@tonic-gate 	if (debug && standalone)
1357*0Sstevel@tonic-gate 		(void) fprintf(stderr, "Sending NAK: %s\n", tp->th_msg);
1358*0Sstevel@tonic-gate 
1359*0Sstevel@tonic-gate 	ret = sendto(peer, &buf, length, 0, (struct sockaddr *)&from,
1360*0Sstevel@tonic-gate 	    fromplen);
1361*0Sstevel@tonic-gate 	if (ret == -1 && errno == EISCONN) {
1362*0Sstevel@tonic-gate 		/* Try without an address */
1363*0Sstevel@tonic-gate 		ret = send(peer, &buf, length, 0);
1364*0Sstevel@tonic-gate 	}
1365*0Sstevel@tonic-gate 	if (ret == -1) {
1366*0Sstevel@tonic-gate 		if (standalone)
1367*0Sstevel@tonic-gate 			perror("sendto (nak)");
1368*0Sstevel@tonic-gate 		else
1369*0Sstevel@tonic-gate 			syslog(LOG_ERR, "tftpd: nak: %m\n");
1370*0Sstevel@tonic-gate 	} else if (ret != length) {
1371*0Sstevel@tonic-gate 		if (standalone)
1372*0Sstevel@tonic-gate 			perror("sendto (nak) lost data");
1373*0Sstevel@tonic-gate 		else
1374*0Sstevel@tonic-gate 			syslog(LOG_ERR, "tftpd: nak: %d lost\n", length - ret);
1375*0Sstevel@tonic-gate 	}
1376*0Sstevel@tonic-gate }
1377