main.c

早期freebsd实现

/*
 * Copyright (c) 1983 Eric P. Allman
 * Copyright (c) 1988, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#ifndef lint
static char copyright[] =
"@(#) Copyright (c) 1988, 1993\n\
	The Regents of the University of California.  All rights reserved.\n";
#endif /* not lint */

#ifndef lint
static char sccsid[] = "@(#)main.c	8.55 (Berkeley) 4/15/94";
#endif /* not lint */

#define	_DEFINE

#include "sendmail.h"
#if NAMED_BIND
#include <arpa/nameser.h>
#include <resolv.h>
#endif
#include <pwd.h>

# ifdef lint
char	edata, end;
# endif /* lint */

/*
**  SENDMAIL -- Post mail to a set of destinations.
**
**	This is the basic mail router.  All user mail programs should
**	call this routine to actually deliver mail.  Sendmail in
**	turn calls a bunch of mail servers that do the real work of
**	delivering the mail.
**
**	Sendmail is driven by tables read in from /usr/lib/sendmail.cf
**	(read by readcf.c).  Some more static configuration info,
**	including some code that you may want to tailor for your
**	installation, is in conf.c.  You may also want to touch
**	daemon.c (if you have some other IPC mechanism), acct.c
**	(to change your accounting), names.c (to adjust the name
**	server mechanism).
**
**	Usage:
**		/usr/lib/sendmail [flags] addr ...
**
**		See the associated documentation for details.
**
**	Author:
**		Eric Allman, UCB/INGRES (until 10/81)
**			     Britton-Lee, Inc., purveyors of fine
**				database computers (from 11/81)
**			     Now back at UCB at the Mammoth project.
**		The support of the INGRES Project and Britton-Lee is
**			gratefully acknowledged.  Britton-Lee in
**			particular had absolutely nothing to gain from
**			my involvement in this project.
*/


int		NextMailer;	/* "free" index into Mailer struct */
char		*FullName;	/* sender's full name */
ENVELOPE	BlankEnvelope;	/* a "blank" envelope */
ENVELOPE	MainEnvelope;	/* the envelope around the basic letter */
ADDRESS		NullAddress =	/* a null address */
		{ "", "", NULL, "" };
char		*UserEnviron[MAXUSERENVIRON + 2];
				/* saved user environment */
char		RealUserName[256];	/* the actual user id on this host */
char		*CommandLineArgs;	/* command line args for pid file */
bool		Warn_Q_option = FALSE;	/* warn about Q option use */

/*
**  Pointers for setproctitle.
**	This allows "ps" listings to give more useful information.
*/

# ifdef SETPROCTITLE
char		**Argv = NULL;		/* pointer to argument vector */
char		*LastArgv = NULL;	/* end of argv */
# endif /* SETPROCTITLE */

static void	obsolete();

#ifdef DAEMON
#ifndef SMTP
ERROR %%%%   Cannot have daemon mode without SMTP   %%%% ERROR
#endif /* SMTP */
#endif /* DAEMON */

#define MAXCONFIGLEVEL	5	/* highest config version level known */

main(argc, argv, envp)
	int argc;
	char **argv;
	char **envp;
{
	register char *p;
	char **av;
	extern int finis();
	extern char Version[];
	char *ep, *from;
	typedef int (*fnptr)();
	STAB *st;
	register int i;
	int j;
	bool queuemode = FALSE;		/* process queue requests */
	bool safecf = TRUE;
	bool warn_C_flag = FALSE;
	char warn_f_flag = '\0';
	static bool reenter = FALSE;
	char *argv0 = argv[0];
	struct passwd *pw;
	struct stat stb;
	char jbuf[MAXHOSTNAMELEN];	/* holds MyHostName */
	extern int DtableSize;
	extern int optind;
	extern time_t convtime();
	extern putheader(), putbody();
	extern void intsig();
	extern char **myhostname();
	extern char *arpadate();
	extern char *getauthinfo();
	extern char *getcfname();
	extern char *optarg;
	extern char **environ;
	extern void sigusr1();

	/*
	**  Check to see if we reentered.
	**	This would normally happen if e_putheader or e_putbody
	**	were NULL when invoked.
	*/

	if (reenter)
	{
		syserr("main: reentered!");
		abort();
	}
	reenter = TRUE;

	/* do machine-dependent initializations */
	init_md(argc, argv);

	/* arrange to dump state on signal */
#ifdef SIGUSR1
	setsignal(SIGUSR1, sigusr1);
#endif

	/* in 4.4BSD, the table can be huge; impose a reasonable limit */
	DtableSize = getdtsize();
	if (DtableSize > 256)
		DtableSize = 256;

	/*
	**  Be sure we have enough file descriptors.
	**	But also be sure that 0, 1, & 2 are open.
	*/

	i = open("/dev/null", O_RDWR, 0);
	if (fstat(STDIN_FILENO, &stb) < 0 && errno != EOPNOTSUPP)
		(void) dup2(i, STDIN_FILENO);
	if (fstat(STDOUT_FILENO, &stb) < 0 && errno != EOPNOTSUPP)
		(void) dup2(i, STDOUT_FILENO);
	if (fstat(STDERR_FILENO, &stb) < 0 && errno != EOPNOTSUPP)
		(void) dup2(i, STDERR_FILENO);
	if (i != STDIN_FILENO && i != STDOUT_FILENO && i != STDERR_FILENO)
		(void) close(i);

	i = DtableSize;
	while (--i > 0)
	{
		if (i != STDIN_FILENO && i != STDOUT_FILENO && i != STDERR_FILENO)
			(void) close(i);
	}
	errno = 0;

#ifdef LOG
# ifdef LOG_MAIL
	openlog("sendmail", LOG_PID, LOG_MAIL);
# else 
	openlog("sendmail", LOG_PID);
# endif
#endif 

	/* set up the blank envelope */
	BlankEnvelope.e_puthdr = putheader;
	BlankEnvelope.e_putbody = putbody;
	BlankEnvelope.e_xfp = NULL;
	STRUCTCOPY(NullAddress, BlankEnvelope.e_from);
	CurEnv = &BlankEnvelope;
	STRUCTCOPY(NullAddress, MainEnvelope.e_from);

	/*
	**  Set default values for variables.
	**	These cannot be in initialized data space.
	*/

	setdefaults(&BlankEnvelope);

	RealUid = getuid();
	RealGid = getgid();

	pw = getpwuid(RealUid);
	if (pw != NULL)
		(void) strcpy(RealUserName, pw->pw_name);
	else
		(void) sprintf(RealUserName, "Unknown UID %d", RealUid);

	/* save command line arguments */
	i = 0;
	for (av = argv; *av != NULL; )
		i += strlen(*av++) + 1;
	CommandLineArgs = xalloc(i);
	p = CommandLineArgs;
	for (av = argv; *av != NULL; )
	{
		if (av != argv)
			*p++ = ' ';
		strcpy(p, *av++);
		p += strlen(p);
	}

	/* Handle any non-getoptable constructions. */
	obsolete(argv);

	/*
	**  Do a quick prescan of the argument list.
	*/

#if defined(__osf__) || defined(_AIX3)
# define OPTIONS	"B:b:C:cd:e:F:f:h:Iimno:p:q:r:sTtvX:x"
#endif
#if defined(ultrix)
# define OPTIONS	"B:b:C:cd:e:F:f:h:IiM:mno:p:q:r:sTtvX:"
#endif
#if defined(NeXT)
# define OPTIONS	"B:b:C:cd:e:F:f:h:IimnOo:p:q:r:sTtvX:"
#endif
#ifndef OPTIONS
# define OPTIONS	"B:b:C:cd:e:F:f:h:Iimno:p:q:r:sTtvX:"
#endif
	while ((j = getopt(argc, argv, OPTIONS)) != EOF)
	{
		switch (j)
		{
		  case 'd':
			tTsetup(tTdvect, sizeof tTdvect, "0-99.1");
			tTflag(optarg);
			setbuf(stdout, (char *) NULL);
			printf("Version %s\n", Version);
			break;
		}
	}

	InChannel = stdin;
	OutChannel = stdout;

	/*
	**  Move the environment so setproctitle can use the space at
	**  the top of memory.
	*/

	for (i = j = 0; j < MAXUSERENVIRON && (p = envp[i]) != NULL; i++)
	{
		if (strncmp(p, "FS=", 3) == 0 || strncmp(p, "LD_", 3) == 0)
			continue;
		UserEnviron[j++] = newstr(p);
	}
	UserEnviron[j] = NULL;
	environ = UserEnviron;

# ifdef SETPROCTITLE
	/*
	**  Save start and extent of argv for setproctitle.
	*/

	Argv = argv;
	if (i > 0)
		LastArgv = envp[i - 1] + strlen(envp[i - 1]);
	else
		LastArgv = argv[argc - 1] + strlen(argv[argc - 1]);
# endif /* SETPROCTITLE */

	if (setsignal(SIGINT, SIG_IGN) != SIG_IGN)
		(void) setsignal(SIGINT, intsig);
	if (setsignal(SIGHUP, SIG_IGN) != SIG_IGN)
		(void) setsignal(SIGHUP, intsig);
	(void) setsignal(SIGTERM, intsig);
	(void) setsignal(SIGPIPE, SIG_IGN);
	OldUmask = umask(022);
	OpMode = MD_DELIVER;
	FullName = getenv("NAME");

#if NAMED_BIND
	if (tTd(8, 8))
		_res.options |= RES_DEBUG;
#endif

	errno = 0;
	from = NULL;

	/* initialize some macros, etc. */
	initmacros(CurEnv);

	/* version */
	define('v', Version, CurEnv);

	/* hostname */
	av = myhostname(jbuf, sizeof jbuf);
	if (jbuf[0] != '\0')
	{
		struct	utsname	utsname;

		if (tTd(0, 4))
			printf("canonical name: %s\n", jbuf);
		define('w', newstr(jbuf), CurEnv);	/* must be new string */
		define('j', newstr(jbuf), CurEnv);
		setclass('w', jbuf);

		p = strchr(jbuf, '.');
		if (p != NULL)
		{
			if (p[1] != '\0')
			{
				define('m', newstr(&p[1]), CurEnv);
				setclass('m', &p[1]);
			}
			while (p != NULL && strchr(&p[1], '.') != NULL)
			{
				*p = '\0';
				setclass('w', jbuf);
				*p++ = '.';
				p = strchr(p, '.');
			}
		}

		if (uname(&utsname) >= 0)
			p = utsname.nodename;
		else
		{
			if (tTd(0, 22))
				printf("uname failed (%s)\n", errstring(errno));
			makelower(jbuf);
			p = jbuf;
		}
		if (tTd(0, 4))
			printf("UUCP nodename: %s\n", p);
		p = newstr(p);
		define('k', p, CurEnv);
		setclass('k', p);
		setclass('w', p);
	}
	while (av != NULL && *av != NULL)
	{
		if (tTd(0, 4))
			printf("\ta.k.a.: %s\n", *av);
		setclass('w', *av++);
	}

	/* current time */
	define('b', arpadate((char *) NULL), CurEnv);

	/*
	**  Find our real host name for future logging.
	*/

	p = getauthinfo(STDIN_FILENO);
	define('_', p, CurEnv);

	/*
	** Crack argv.
	*/

	av = argv;
	p = strrchr(*av, '/');
	if (p++ == NULL)
		p = *av;
	if (strcmp(p, "newaliases") == 0)
		OpMode = MD_INITALIAS;
	else if (strcmp(p, "mailq") == 0)
		OpMode = MD_PRINT;
	else if (strcmp(p, "smtpd") == 0)
		OpMode = MD_DAEMON;

	optind = 1;
	while ((j = getopt(argc, argv, OPTIONS)) != EOF)
	{
		switch (j)
		{
		  case 'b':	/* operations mode */
			switch (j = *optarg)
			{
			  case MD_DAEMON:
# ifdef DAEMON
				if (RealUid != 0) {
					usrerr("Permission denied");
					exit (EX_USAGE);
				}
				(void) unsetenv("HOSTALIASES");
# else
				usrerr("Daemon mode not implemented");
				ExitStat = EX_USAGE;
				break;
# endif /* DAEMON */
			  case MD_SMTP:
# ifndef SMTP
				usrerr("I don't speak SMTP");
				ExitStat = EX_USAGE;
				break;
# endif /* SMTP */
			  case MD_DELIVER:
			  case MD_VERIFY:
			  case MD_TEST:
			  case MD_INITALIAS:
			  case MD_PRINT:
#ifdef MAYBE_NEXT_RELEASE
			  case MD_ARPAFTP:
#endif
				OpMode = j;
				break;

			  case MD_FREEZE:
				usrerr("Frozen configurations unsupported");
				ExitStat = EX_USAGE;
				break;

			  default:
				usrerr("Invalid operation mode %c", j);
				ExitStat = EX_USAGE;
				break;
			}
			break;

		  case 'B':	/* body type */
			CurEnv->e_bodytype = newstr(optarg);
			break;

		  case 'C':	/* select configuration file (already done) */
			if (RealUid != 0)
				warn_C_flag = TRUE;
			ConfFile = optarg;
			(void) setgid(RealGid);
			(void) setuid(RealUid);
			safecf = FALSE;
			break;

		  case 'd':	/* debugging -- already done */
			break;

		  case 'f':	/* from address */
		  case 'r':	/* obsolete -f flag */
			if (from != NULL)
			{
				usrerr("More than one \"from\" person");
				ExitStat = EX_USAGE;
				break;
			}
			from = newstr(optarg);
			if (strcmp(RealUserName, from) != 0)
				warn_f_flag = j;
			break;

		  case 'F':	/* set full name */