NetBSD/usr.bin/vacation/vacation.c

655 lines
14 KiB
C

/* $NetBSD: vacation.c,v 1.34 2007/07/13 14:52:15 christos Exp $ */
/*
* Copyright (c) 1983, 1987, 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. 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.
*/
#include <sys/cdefs.h>
#ifndef lint
__COPYRIGHT("@(#) Copyright (c) 1983, 1987, 1993\n\
The Regents of the University of California. All rights reserved.\n");
#endif /* not lint */
#ifndef lint
#if 0
static char sccsid[] = "@(#)vacation.c 8.2 (Berkeley) 1/26/94";
#endif
__RCSID("$NetBSD: vacation.c,v 1.34 2007/07/13 14:52:15 christos Exp $");
#endif /* not lint */
/*
** Vacation
** Copyright (c) 1983 Eric P. Allman
** Berkeley, California
*/
#include <sys/param.h>
#include <sys/stat.h>
#include <ctype.h>
#include <db.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <paths.h>
#include <pwd.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <time.h>
#include <tzfile.h>
#include <unistd.h>
/*
* VACATION -- return a message to the sender when on vacation.
*
* This program is invoked as a message receiver. It returns a
* message specified by the user to whomever sent the mail, taking
* care not to return a message too often to prevent "I am on
* vacation" loops.
*/
#define MAXLINE 1024 /* max line from mail header */
static const char *dbprefix = ".vacation"; /* dbm's database sans .db */
static const char *msgfile = ".vacation.msg"; /* vacation message */
typedef struct alias {
struct alias *next;
const char *name;
} alias_t;
static alias_t *names;
static DB *db;
static char from[MAXLINE];
static char subject[MAXLINE];
static int iflag = 0; /* Initialize the database */
static int tflag = 0;
#define APPARENTLY_TO 1
#define DELIVERED_TO 2
static int fflag = 0;
#define FROM_FROM 1
#define RETURN_PATH_FROM 2
#define SENDER_FROM 4
static int toanybody = 0; /* Don't check if we appear in the to or cc */
static int debug = 0;
static void opendb(void);
static int junkmail(const char *);
static int nsearch(const char *, const char *);
static int readheaders(void);
static int recent(void);
static void getfrom(char *);
static void sendmessage(const char *);
static void setinterval(time_t);
static void setreply(void);
static void usage(void) __attribute__((__noreturn__));
int
main(int argc, char **argv)
{
struct passwd *pw;
alias_t *cur;
long interval;
int ch, rv;
char *p;
setprogname(argv[0]);
opterr = 0;
interval = -1;
openlog(getprogname(), 0, LOG_USER);
while ((ch = getopt(argc, argv, "a:df:F:Iijm:r:s:t:T:")) != -1)
switch((char)ch) {
case 'a': /* alias */
if (!(cur = (alias_t *)malloc((size_t)sizeof(alias_t))))
break;
cur->name = optarg;
cur->next = names;
names = cur;
break;
case 'd':
debug++;
break;
case 'F':
for (p = optarg; *p; p++)
switch (*p) {
case 'F':
fflag |= FROM_FROM;
break;
case 'R':
fflag |= RETURN_PATH_FROM;
break;
case 'S':
fflag |= SENDER_FROM;
break;
default:
errx(1, "Unknown -f option `%c'", *p);
}
break;
case 'f':
dbprefix = optarg;
break;
case 'I': /* backward compatible */
case 'i': /* init the database */
iflag = 1;
break;
case 'j':
toanybody = 1;
break;
case 'm':
msgfile = optarg;
break;
case 'r':
case 't': /* Solaris compatibility */
if (!isdigit((unsigned char)*optarg)) {
interval = LONG_MAX;
break;
}
if (*optarg == '\0')
goto bad;
interval = strtol(optarg, &p, 0);
if (errno == ERANGE &&
(interval == LONG_MAX || interval == LONG_MIN))
err(1, "Bad interval `%s'", optarg);
switch (*p) {
case 's':
break;
case 'm':
interval *= SECSPERMIN;
break;
case 'h':
interval *= SECSPERHOUR;
break;
case 'd':
case '\0':
interval *= SECSPERDAY;
break;
case 'w':
interval *= DAYSPERWEEK * SECSPERDAY;
break;
default:
bad:
errx(1, "Invalid interval `%s'", optarg);
}
if (interval < 0 || (*p && p[1]))
goto bad;
break;
case 's':
(void)strlcpy(from, optarg, sizeof(from));
break;
case 'T':
for (p = optarg; *p; p++)
switch (*p) {
case 'A':
tflag |= APPARENTLY_TO;
break;
case 'D':
tflag |= DELIVERED_TO;
break;
default:
errx(1, "Unknown -t option `%c'", *p);
}
break;
case '?':
default:
usage();
}
argc -= optind;
argv += optind;
if (argc != 1) {
if (!iflag)
usage();
if (!(pw = getpwuid(getuid()))) {
syslog(LOG_ERR, "%s: no such user uid %u.",
getprogname(), getuid());
exit(1);
}
}
else if (!(pw = getpwnam(*argv))) {
syslog(LOG_ERR, "%s: no such user %s.",
getprogname(), *argv);
exit(1);
}
if (chdir(pw->pw_dir) == -1 &&
(dbprefix[0] != '/' || msgfile[0] != '/')) {
syslog(LOG_ERR, "%s: no such directory %s.",
getprogname(), pw->pw_dir);
exit(1);
}
opendb();
if (interval != -1)
setinterval((time_t)interval);
if (iflag) {
(void)(db->close)(db);
exit(0);
}
if (!(cur = malloc((size_t)sizeof(alias_t)))) {
syslog(LOG_ERR, "%s: %m", getprogname());
(void)(db->close)(db);
exit(1);
}
cur->name = pw->pw_name;
cur->next = names;
names = cur;
if ((rv = readheaders()) != -1) {
(void)(db->close)(db);
exit(rv);
}
if (!recent()) {
setreply();
(void)(db->close)(db);
sendmessage(pw->pw_name);
}
else
(void)(db->close)(db);
exit(0);
/* NOTREACHED */
}
static void
opendb(void)
{
char path[MAXPATHLEN];
(void)snprintf(path, sizeof(path), "%s.db", dbprefix);
db = dbopen(path, O_CREAT|O_RDWR | (iflag ? O_TRUNC : 0),
S_IRUSR|S_IWUSR, DB_HASH, NULL);
if (!db) {
syslog(LOG_ERR, "%s: %s: %m", getprogname(), path);
exit(1);
}
}
/*
* readheaders --
* read mail headers
*/
static int
readheaders(void)
{
alias_t *cur;
char *p;
int tome, cont;
char buf[MAXLINE];
cont = tome = 0;
#define COMPARE(a, b) strncmp(a, b, sizeof(b) - 1)
#define CASECOMPARE(a, b) strncasecmp(a, b, sizeof(b) - 1)
while (fgets(buf, sizeof(buf), stdin) && *buf != '\n')
switch(*buf) {
case 'F': /* "From " or "From:" */
cont = 0;
if (COMPARE(buf, "From ") == 0)
getfrom(buf + sizeof("From ") - 1);
if ((fflag & FROM_FROM) != 0 &&
COMPARE(buf, "From:") == 0)
getfrom(buf + sizeof("From:") - 1);
break;
case 'P': /* "Precedence:" */
cont = 0;
if (CASECOMPARE(buf, "Precedence") != 0 ||
(buf[10] != ':' && buf[10] != ' ' &&
buf[10] != '\t'))
break;
if ((p = strchr(buf, ':')) == NULL)
break;
while (*++p && isspace((unsigned char)*p))
continue;
if (!*p)
break;
if (CASECOMPARE(p, "junk") == 0 ||
CASECOMPARE(p, "bulk") == 0||
CASECOMPARE(p, "list") == 0)
exit(0);
break;
case 'C': /* "Cc:" */
if (COMPARE(buf, "Cc:"))
break;
cont = 1;
goto findme;
case 'T': /* "To:" */
if (COMPARE(buf, "To:"))
break;
cont = 1;
goto findme;
case 'A': /* "Apparently-To:" */
if ((tflag & APPARENTLY_TO) == 0 ||
COMPARE(buf, "Apparently-To:") != 0)
break;
cont = 1;
goto findme;
case 'D': /* "Delivered-To:" */
if ((tflag & DELIVERED_TO) == 0 ||
COMPARE(buf, "Delivered-To:") != 0)
break;
cont = 1;
goto findme;
case 'R': /* "Return-Path:" */
cont = 0;
if ((fflag & RETURN_PATH_FROM) != 0 &&
COMPARE(buf, "Return-Path:") == 0)
getfrom(buf + sizeof("Return-Path:") - 1);
break;
case 'S': /* "Sender:" */
cont = 0;
if (COMPARE(buf, "Subject:") == 0) {
/* trim leading blanks */
char *s = NULL;
for (p = buf + sizeof("Subject:") - 1; *p; p++)
if (s == NULL &&
!isspace((unsigned char)*p))
s = p;
/* trim trailing blanks */
if (s) {
for (--p; p != s; p--)
if (!isspace((unsigned char)*p))
break;
*++p = '\0';
}
if (s) {
(void)strlcpy(subject, s, sizeof(subject));
} else {
subject[0] = '\0';
}
}
if ((fflag & SENDER_FROM) != 0 &&
COMPARE(buf, "Sender:") == 0)
getfrom(buf + sizeof("Sender:") - 1);
break;
default:
if (!isspace((unsigned char)*buf) || !cont || tome) {
cont = 0;
break;
}
findme: for (cur = names; !tome && cur; cur = cur->next)
tome += nsearch(cur->name, buf);
}
if (!toanybody && !tome)
return 0;
if (!*from) {
syslog(LOG_ERR, "%s: no initial \"From\" line.",
getprogname());
return 1;
}
return -1;
}
/*
* nsearch --
* do a nice, slow, search of a string for a substring.
*/
static int
nsearch(const char *name, const char *str)
{
size_t len;
for (len = strlen(name); *str; ++str)
if (!strncasecmp(name, str, len))
return(1);
return(0);
}
/*
* getfrom --
* return the first string in the buffer, stripping leading and trailing
* blanks and <>.
*/
void
getfrom(char *buf)
{
char *s, *p;
if ((s = strchr(buf, '<')) != NULL)
s++;
else
s = buf;
for (; *s && isspace((unsigned char)*s); s++)
continue;
for (p = s; *p && !isspace((unsigned char)*p); p++)
continue;
if (*--p == '>')
*p = '\0';
else
*++p = '\0';
if (junkmail(s))
exit(0);
if (!*from)
(void)strlcpy(from, s, sizeof(from));
}
/*
* junkmail --
* read the header and return if automagic/junk/bulk/list mail
*/
static int
junkmail(const char *addr)
{
static struct ignore {
const char *name;
size_t len;
} ignore[] = {
#define INIT(a) { a, sizeof(a) - 1 }
INIT("-request"),
INIT("postmaster"),
INIT("uucp"),
INIT("mailer-daemon"),
INIT("mailer"),
INIT("-relay"),
{NULL, 0 }
};
struct ignore *cur;
size_t len;
const char *p;
/*
* This is mildly amusing, and I'm not positive it's right; trying
* to find the "real" name of the sender, assuming that addresses
* will be some variant of:
*
* From site!site!SENDER%site.domain%site.domain@site.domain
*/
if (!(p = strchr(addr, '%')))
if (!(p = strchr(addr, '@'))) {
if ((p = strrchr(addr, '!')) != NULL)
++p;
else
p = addr;
for (; *p; ++p)
continue;
}
len = p - addr;
for (cur = ignore; cur->name; ++cur)
if (len >= cur->len &&
!strncasecmp(cur->name, p - cur->len, cur->len))
return(1);
return(0);
}
#define VIT "__VACATION__INTERVAL__TIMER__"
/*
* recent --
* find out if user has gotten a vacation message recently.
* use memmove for machines with alignment restrictions
*/
static int
recent(void)
{
DBT key, data;
time_t then, next;
/* get interval time */
key.data = (void *)(intptr_t)VIT;
key.size = sizeof(VIT);
if ((db->get)(db, &key, &data, 0))
next = SECSPERDAY * DAYSPERWEEK;
else
(void)memmove(&next, data.data, sizeof(next));
/* get record for this address */
key.data = from;
key.size = strlen(from);
if (!(db->get)(db, &key, &data, 0)) {
(void)memmove(&then, data.data, sizeof(then));
if (next == (time_t)LONG_MAX || /* XXX */
then + next > time(NULL))
return(1);
}
return(0);
}
/*
* setinterval --
* store the reply interval
*/
static void
setinterval(time_t interval)
{
DBT key, data;
key.data = (void *)(intptr_t)VIT;
key.size = sizeof(VIT);
data.data = &interval;
data.size = sizeof(interval);
(void)(db->put)(db, &key, &data, 0);
}
/*
* setreply --
* store that this user knows about the vacation.
*/
static void
setreply(void)
{
DBT key, data;
time_t now;
key.data = from;
key.size = strlen(from);
(void)time(&now);
data.data = &now;
data.size = sizeof(now);
(void)(db->put)(db, &key, &data, 0);
}
/*
* sendmessage --
* exec sendmail to send the vacation file to sender
*/
static void
sendmessage(const char *myname)
{
FILE *mfp, *sfp;
int i;
int pvect[2];
char buf[MAXLINE];
mfp = fopen(msgfile, "r");
if (mfp == NULL) {
syslog(LOG_ERR, "%s: no `%s' file for `%s'.", getprogname(),
myname, msgfile);
exit(1);
}
if (debug) {
sfp = stdout;
} else {
if (pipe(pvect) < 0) {
syslog(LOG_ERR, "%s: pipe: %m", getprogname());
exit(1);
}
i = vfork();
if (i < 0) {
syslog(LOG_ERR, "%s: fork: %m", getprogname());
exit(1);
}
if (i == 0) {
(void)dup2(pvect[0], 0);
(void)close(pvect[0]);
(void)close(pvect[1]);
(void)close(fileno(mfp));
(void)execl(_PATH_SENDMAIL, "sendmail", "-f", myname,
"--", from, NULL);
syslog(LOG_ERR, "%s: can't exec %s: %m",
getprogname(), _PATH_SENDMAIL);
_exit(1);
}
(void)close(pvect[0]);
sfp = fdopen(pvect[1], "w");
if (sfp == NULL) {
syslog(LOG_ERR, "%s: can't fdopen %d: %m",
getprogname(), pvect[1]);
_exit(1);
}
}
(void)fprintf(sfp, "To: %s\n", from);
(void)fputs("Auto-Submitted: auto-replied\n", sfp);
while (fgets(buf, sizeof buf, mfp) != NULL) {
char *p;
if ((p = strstr(buf, "$SUBJECT")) != NULL) {
*p = '\0';
(void)fputs(buf, sfp);
(void)fputs(subject, sfp);
p += sizeof("$SUBJECT") - 1;
(void)fputs(p, sfp);
} else
(void)fputs(buf, sfp);
}
(void)fclose(mfp);
if (sfp != stdout)
(void)fclose(sfp);
}
static void
usage(void)
{
syslog(LOG_ERR, "uid %u: Usage: %s [-dIij] [-a alias] [-f database_file] [-F F|R|S] [-m message_file] [-s sender] [-t interval] [-T A|D]"
" login", getuid(), getprogname());
exit(1);
}