recipient.c

早期freebsd实现

	*fuzzyp = FALSE;

	/* DEC Hesiod getpwnam accepts numeric strings -- short circuit it */
	for (p = name; *p != '\0'; p++)
		if (!isascii(*p) || !isdigit(*p))
			break;
	if (*p == '\0')
	{
		if (tTd(29, 4))
			printf("failed (numeric input)\n");
		return NULL;
	}

	/* look up this login name using fast path */
	if ((pw = getpwnam(name)) != NULL)
	{
		if (tTd(29, 4))
			printf("found (non-fuzzy)\n");
		return (pw);
	}

#ifdef MATCHGECOS
	/* see if fuzzy matching allowed */
	if (!MatchGecos)
	{
		if (tTd(29, 4))
			printf("not found (fuzzy disabled)\n");
		return NULL;
	}

	/* search for a matching full name instead */
	for (p = name; *p != '\0'; p++)
	{
		if (*p == (SpaceSub & 0177) || *p == '_')
			*p = ' ';
	}
	(void) setpwent();
	while ((pw = getpwent()) != NULL)
	{
		char buf[MAXNAME];

		buildfname(pw->pw_gecos, pw->pw_name, buf);
		if (strchr(buf, ' ') != NULL && !strcasecmp(buf, name))
		{
			if (tTd(29, 4))
				printf("fuzzy matches %s\n", pw->pw_name);
			message("sending to login name %s", pw->pw_name);
			*fuzzyp = TRUE;
			return (pw);
		}
	}
	if (tTd(29, 4))
		printf("no fuzzy match found\n");
#else
	if (tTd(29, 4))
		printf("not found (fuzzy disabled)\n");
#endif
	return (NULL);
}
/*
**  WRITABLE -- predicate returning if the file is writable.
**
**	This routine must duplicate the algorithm in sys/fio.c.
**	Unfortunately, we cannot use the access call since we
**	won't necessarily be the real uid when we try to
**	actually open the file.
**
**	Notice that ANY file with ANY execute bit is automatically
**	not writable.  This is also enforced by mailfile.
**
**	Parameters:
**		filename -- the file name to check.
**		ctladdr -- the controlling address for this file.
**		flags -- SFF_* flags to control the function.
**
**	Returns:
**		TRUE -- if we will be able to write this file.
**		FALSE -- if we cannot write this file.
**
**	Side Effects:
**		none.
*/

bool
writable(filename, ctladdr, flags)
	char *filename;
	ADDRESS *ctladdr;
	int flags;
{
	uid_t euid;
	gid_t egid;
	int bits;
	register char *p;
	char *uname;
	struct stat stb;
	extern char RealUserName[];

	if (tTd(29, 5))
		printf("writable(%s, %x)\n", filename, flags);

#ifdef HASLSTAT
	if ((bitset(SFF_NOSLINK, flags) ? lstat(filename, &stb)
					: stat(filename, &stb)) < 0)
#else
	if (stat(filename, &stb) < 0)
#endif
	{
		/* file does not exist -- see if directory is safe */
		p = strrchr(filename, '/');
		if (p == NULL)
		{
			errno = ENOTDIR;
			return FALSE;
		}
		*p = '\0';
		errno = safefile(filename, RealUid, RealGid, RealUserName,
				 SFF_MUSTOWN, S_IWRITE|S_IEXEC);
		*p = '/';
		return errno == 0;
	}

#ifdef SUID_ROOT_FILES_OK
	/* really ought to be passed down -- and not a good idea */
	flags |= SFF_ROOTOK;
#endif

	/*
	**  File does exist -- check that it is writable.
	*/

	if (bitset(0111, stb.st_mode))
	{
		if (tTd(29, 5))
			printf("failed (mode %o: x bits)\n", stb.st_mode);
		errno = EPERM;
		return (FALSE);
	}

	if (ctladdr != NULL && geteuid() == 0)
	{
		euid = ctladdr->q_uid;
		egid = ctladdr->q_gid;
		uname = ctladdr->q_user;
	}
	else
	{
		euid = RealUid;
		egid = RealGid;
		uname = RealUserName;
	}
	if (euid == 0)
	{
		euid = DefUid;
		uname = DefUser;
	}
	if (egid == 0)
		egid = DefGid;
	if (geteuid() == 0)
	{
		if (bitset(S_ISUID, stb.st_mode) &&
		    (stb.st_uid != 0 || bitset(SFF_ROOTOK, flags)))
		{
			euid = stb.st_uid;
			uname = NULL;
		}
		if (bitset(S_ISGID, stb.st_mode) &&
		    (stb.st_gid != 0 || bitset(SFF_ROOTOK, flags)))
			egid = stb.st_gid;
	}

	if (tTd(29, 5))
		printf("\teu/gid=%d/%d, st_u/gid=%d/%d\n",
			euid, egid, stb.st_uid, stb.st_gid);

	errno = safefile(filename, euid, egid, uname, flags, S_IWRITE);
	return errno == 0;
}
/*
**  INCLUDE -- handle :include: specification.
**
**	Parameters:
**		fname -- filename to include.
**		forwarding -- if TRUE, we are reading a .forward file.
**			if FALSE, it's a :include: file.
**		ctladdr -- address template to use to fill in these
**			addresses -- effective user/group id are
**			the important things.
**		sendq -- a pointer to the head of the send queue
**			to put these addresses in.
**
**	Returns:
**		open error status
**
**	Side Effects:
**		reads the :include: file and sends to everyone
**		listed in that file.
**
**	Security Note:
**		If you have restricted chown (that is, you can't
**		give a file away), it is reasonable to allow programs
**		and files called from this :include: file to be to be
**		run as the owner of the :include: file.  This is bogus
**		if there is any chance of someone giving away a file.
**		We assume that pre-POSIX systems can give away files.
**
**		There is an additional restriction that if you
**		forward to a :include: file, it will not take on
**		the ownership of the :include: file.  This may not
**		be necessary, but shouldn't hurt.
*/

static jmp_buf	CtxIncludeTimeout;
static int	includetimeout();

#ifndef S_IWOTH
# define S_IWOTH	(S_IWRITE >> 6)
#endif

int
include(fname, forwarding, ctladdr, sendq, e)
	char *fname;
	bool forwarding;
	ADDRESS *ctladdr;
	ADDRESS **sendq;
	ENVELOPE *e;
{
	register FILE *fp = NULL;
	char *oldto = e->e_to;
	char *oldfilename = FileName;
	int oldlinenumber = LineNumber;
	register EVENT *ev = NULL;
	int nincludes;
	register ADDRESS *ca;
	uid_t saveduid, uid;
	gid_t savedgid, gid;
	char *uname;
	int rval = 0;
	int sfflags = forwarding ? SFF_MUSTOWN : SFF_ANYFILE;
	struct stat st;
	char buf[MAXLINE];
#ifdef _POSIX_CHOWN_RESTRICTED
# if _POSIX_CHOWN_RESTRICTED == -1
#  define safechown	FALSE
# else
#  define safechown	TRUE
# endif
#else
# ifdef _PC_CHOWN_RESTRICTED
	bool safechown;
# else
#  ifdef BSD
#   define safechown	TRUE
#  else
#   define safechown	FALSE
#  endif
# endif
#endif
	extern bool chownsafe();

	if (tTd(27, 2))
		printf("include(%s)\n", fname);
	if (tTd(27, 4))
		printf("   ruid=%d euid=%d\n", getuid(), geteuid());
	if (tTd(27, 14))
	{
		printf("ctladdr ");
		printaddr(ctladdr, FALSE);
	}

	if (tTd(27, 9))
		printf("include: old uid = %d/%d\n", getuid(), geteuid());

	ca = getctladdr(ctladdr);
	if (ca == NULL)
	{
		uid = DefUid;
		gid = DefGid;
		uname = DefUser;
		saveduid = -1;
	}
	else
	{
		uid = ca->q_uid;
		gid = ca->q_gid;
		uname = ca->q_user;
#ifdef HASSETREUID
		saveduid = geteuid();
		savedgid = getegid();
		if (saveduid == 0)
		{
			initgroups(uname, gid);
			if (uid != 0)
				(void) setreuid(0, uid);
		}
#endif                   
	}

	if (tTd(27, 9))
		printf("include: new uid = %d/%d\n", getuid(), geteuid());

	/*
	**  If home directory is remote mounted but server is down,
	**  this can hang or give errors; use a timeout to avoid this
	*/

	if (setjmp(CtxIncludeTimeout) != 0)
	{
		ctladdr->q_flags |= QQUEUEUP;
		errno = 0;

		/* return pseudo-error code */
		rval = EOPENTIMEOUT;
		goto resetuid;
	}
	ev = setevent((time_t) 60, includetimeout, 0);

	/* the input file must be marked safe */
	rval = safefile(fname, uid, gid, uname, sfflags, S_IREAD);
	if (rval != 0)
	{
		/* don't use this :include: file */
		if (tTd(27, 4))
			printf("include: not safe (uid=%d): %s\n",
				uid, errstring(rval));
	}
	else
	{
		fp = fopen(fname, "r");
		if (fp == NULL)
		{
			rval = errno;
			if (tTd(27, 4))
				printf("include: open: %s\n", errstring(rval));
		}
	}
	clrevent(ev);

resetuid:

#ifdef HASSETREUID
	if (saveduid == 0)
	{
		if (uid != 0)
			if (setreuid(-1, 0) < 0 || setreuid(RealUid, 0) < 0)
				syserr("setreuid(%d, 0) failure (real=%d, eff=%d)",
					RealUid, getuid(), geteuid());
		setgid(savedgid);
	}
#endif

	if (tTd(27, 9))
		printf("include: reset uid = %d/%d\n", getuid(), geteuid());

	if (rval == EOPENTIMEOUT)
		usrerr("451 open timeout on %s", fname);

	if (fp == NULL)
		return rval;

	if (fstat(fileno(fp), &st) < 0)
	{
		rval = errno;
		syserr("Cannot fstat %s!", fname);
		return rval;
	}

#ifndef safechown
	safechown = chownsafe(fileno(fp));
#endif
	if (ca == NULL && safechown)
	{
		ctladdr->q_uid = st.st_uid;
		ctladdr->q_gid = st.st_gid;
		ctladdr->q_flags |= QGOODUID;
	}
	if (ca != NULL && ca->q_uid == st.st_uid)
	{
		/* optimization -- avoid getpwuid if we already have info */
		ctladdr->q_flags |= ca->q_flags & QBOGUSSHELL;
		ctladdr->q_ruser = ca->q_ruser;
	}
	else
	{
		char *sh;
		register struct passwd *pw;

		sh = "/SENDMAIL/ANY/SHELL/";
		pw = getpwuid(st.st_uid);
		if (pw != NULL)
		{
			ctladdr->q_ruser = newstr(pw->pw_name);
			if (safechown)
				sh = pw->pw_shell;
		}
		if (pw == NULL)
			ctladdr->q_flags |= QBOGUSSHELL;
		else if(!usershellok(sh))
		{
			if (safechown)
				ctladdr->q_flags |= QBOGUSSHELL;
			else
				ctladdr->q_flags |= QUNSAFEADDR;
		}
	}

	if (bitset(EF_VRFYONLY, e->e_flags))
	{
		/* don't do any more now */
		ctladdr->q_flags |= QVERIFIED;
		e->e_nrcpts++;
		xfclose(fp, "include", fname);
		return rval;
	}

	/*
	** Check to see if some bad guy can write this file
	**
	**	This should really do something clever with group
	**	permissions; currently we just view world writable
	**	as unsafe.  Also, we don't check for writable
	**	directories in the path.  We've got to leave
	**	something for the local sysad to do.
	*/

	if (bitset(S_IWOTH, st.st_mode))
		ctladdr->q_flags |= QUNSAFEADDR;

	/* read the file -- each line is a comma-separated list. */
	FileName = fname;
	LineNumber = 0;
	ctladdr->q_flags &= ~QSELFREF;
	nincludes = 0;
	while (fgets(buf, sizeof buf, fp) != NULL)
	{
		register char *p = strchr(buf, '\n');

		LineNumber++;
		if (p != NULL)
			*p = '\0';
		if (buf[0] == '#' || buf[0] == '\0')
			continue;
		e->e_to = NULL;
		message("%s to %s",
			forwarding ? "forwarding" : "sending", buf);
#ifdef LOG
		if (forwarding && LogLevel > 9)
			syslog(LOG_INFO, "%s: forward %s => %s",
				e->e_id == NULL ? "NOQUEUE" : e->e_id,
				oldto, buf);
#endif

		AliasLevel++;
		nincludes += sendtolist(buf, ctladdr, sendq, e);
		AliasLevel--;
	}

	if (ferror(fp) && tTd(27, 3))
		printf("include: read error: %s\n", errstring(errno));
	if (nincludes > 0 && !bitset(QSELFREF, ctladdr->q_flags))
	{
		if (tTd(27, 5))
		{
			printf("include: QDONTSEND ");
			printaddr(ctladdr, FALSE);
		}
		ctladdr->q_flags |= QDONTSEND;
	}

	(void) xfclose(fp, "include", fname);
	FileName = oldfilename;
	LineNumber = oldlinenumber;
	e->e_to = oldto;
	return rval;
}

static
includetimeout()
{
	longjmp(CtxIncludeTimeout, 1);
}
/*
**  SENDTOARGV -- send to an argument vector.
**
**	Parameters:
**		argv -- argument vector to send to.
**		e -- the current envelope.
**
**	Returns:
**		none.
**
**	Side Effects:
**		puts all addresses on the argument vector onto the
**			send queue.
*/

sendtoargv(argv, e)
	register char **argv;
	register ENVELOPE *e;
{
	register char *p;

	while ((p = *argv++) != NULL)
	{
		(void) sendtolist(p, NULLADDR, &e->e_sendqueue, e);
	}
}
/*
**  GETCTLADDR -- get controlling address from an address header.
**
**	If none, get one corresponding to the effective userid.
**
**	Parameters:
**		a -- the address to find the controller of.
**
**	Returns:
**		the controlling address.
**
**	Side Effects:
**		none.
*/

ADDRESS *
getctladdr(a)
	register ADDRESS *a;
{
	while (a != NULL && !bitset(QGOODUID, a->q_flags))
		a = a->q_alias;
	return (a);
}