freebsd-dev/usr.bin/msgs/msgs.c
Don Lewis dc77866517 Use strlcpy() instead of strncpy() when copying date and subj
to ensure that these are properly NUL terminated since they
are passed to printf().

Reported by:	Coverity
CID:		974770
MFH:		1 week
2016-05-12 08:55:57 +00:00

912 lines
19 KiB
C

/*-
* Copyright (c) 1980, 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.
* 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 const char copyright[] =
"@(#) Copyright (c) 1980, 1993\n\
The Regents of the University of California. All rights reserved.\n";
#endif /* not lint */
#if 0
#ifndef lint
static char sccsid[] = "@(#)msgs.c 8.2 (Berkeley) 4/28/95";
#endif /* not lint */
#endif
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
/*
* msgs - a user bulletin board program
*
* usage:
* msgs [fhlopq] [[-]number] to read messages
* msgs -s to place messages
* msgs -c [-days] to clean up the bulletin board
*
* prompt commands are:
* y print message
* n flush message, go to next message
* q flush message, quit
* p print message, turn on 'pipe thru more' mode
* P print message, turn off 'pipe thru more' mode
* - reprint last message
* s[-][<num>] [<filename>] save message
* m[-][<num>] mail with message in temp mbox
* x exit without flushing this message
* <num> print message number <num>
*/
#define V7 /* will look for TERM in the environment */
#define OBJECT /* will object to messages without Subjects */
/* #define REJECT */ /* will reject messages without Subjects
(OBJECT must be defined also) */
/* #define UNBUFFERED *//* use unbuffered output */
#include <sys/param.h>
#include <sys/stat.h>
#include <ctype.h>
#include <dirent.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <locale.h>
#include <pwd.h>
#include <setjmp.h>
#include <termcap.h>
#include <termios.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
#include "pathnames.h"
#define CMODE 0644 /* bounds file creation mode */
#define NO 0
#define YES 1
#define SUPERUSER 0 /* superuser uid */
#define DAEMON 1 /* daemon uid */
#define NLINES 24 /* default number of lines/crt screen */
#define NDAYS 21 /* default keep time for messages */
#define DAYS *24*60*60 /* seconds/day */
#define MSGSRC ".msgsrc" /* user's rc file */
#define BOUNDS "bounds" /* message bounds file */
#define NEXT "Next message? [yq]"
#define MORE "More? [ynq]"
#define NOMORE "(No more) [q] ?"
typedef char bool;
static FILE *msgsrc;
static FILE *newmsg;
static const char *sep = "-";
static char inbuf[BUFSIZ];
static char fname[MAXPATHLEN];
static char cmdbuf[MAXPATHLEN + MAXPATHLEN];
static char subj[128];
static char from[128];
static char date[128];
static char *ptr;
static char *in;
static bool local;
static bool ruptible;
static bool totty;
static bool seenfrom;
static bool seensubj;
static bool blankline;
static bool printing = NO;
static bool mailing = NO;
static bool quitit = NO;
static bool sending = NO;
static bool intrpflg = NO;
static uid_t uid;
static int msg;
static int prevmsg;
static int lct;
static int nlines;
static int Lpp = 0;
static time_t t;
static time_t keep;
/* option initialization */
static bool hdrs = NO;
static bool qopt = NO;
static bool hush = NO;
static bool send_msg = NO;
static bool locomode = NO;
static bool use_pager = NO;
static bool clean = NO;
static bool lastcmd = NO;
static jmp_buf tstpbuf;
static void ask(const char *);
static void gfrsub(FILE *);
static int linecnt(FILE *);
static int next(char *);
static char *nxtfld(char *);
static void onsusp(int);
static void onintr(int);
static void prmesg(int);
static void usage(void);
int
main(int argc, char *argv[])
{
bool newrc, already;
int rcfirst = 0; /* first message to print (from .rc) */
int rcback = 0; /* amount to back off of rcfirst */
int firstmsg = 0, nextmsg = 0, lastmsg = 0;
int blast = 0;
struct stat buf; /* stat to check access of bounds */
FILE *bounds;
char *cp;
#ifdef UNBUFFERED
setbuf(stdout, NULL);
#endif
setlocale(LC_ALL, "");
time(&t);
if (setuid(uid = getuid()) != 0)
err(1, "setuid failed");
ruptible = (signal(SIGINT, SIG_IGN) == SIG_DFL);
if (ruptible)
signal(SIGINT, SIG_DFL);
argc--, argv++;
while (argc > 0) {
if (isdigit(argv[0][0])) { /* starting message # */
rcfirst = atoi(argv[0]);
}
else if (isdigit(argv[0][1])) { /* backward offset */
rcback = atoi( &( argv[0][1] ) );
}
else {
ptr = *argv;
while (*ptr) switch (*ptr++) {
case '-':
break;
case 'c':
if (uid != SUPERUSER && uid != DAEMON)
errx(1,
"only the super-user can use the c flag");
clean = YES;
break;
case 'f': /* silently */
hush = YES;
break;
case 'h': /* headers only */
hdrs = YES;
break;
case 'l': /* local msgs only */
locomode = YES;
break;
case 'o': /* option to save last message */
lastcmd = YES;
break;
case 'p': /* pipe thru 'more' during long msgs */
use_pager = YES;
break;
case 'q': /* query only */
qopt = YES;
break;
case 's': /* sending TO msgs */
send_msg = YES;
break;
default:
usage();
}
}
argc--, argv++;
}
/*
* determine current message bounds
*/
snprintf(fname, sizeof(fname), "%s/%s", _PATH_MSGS, BOUNDS);
/*
* Test access rights to the bounds file
* This can be a little tricky. if(send_msg), then
* we will create it. We assume that if(send_msg),
* then you have write permission there.
* Else, it better be there, or we bail.
*/
if (send_msg != YES) {
if (stat(fname, &buf) < 0) {
if (hush != YES) {
err(errno, "%s", fname);
} else {
exit(1);
}
}
}
bounds = fopen(fname, "r");
if (bounds != NULL) {
fscanf(bounds, "%d %d\n", &firstmsg, &lastmsg);
fclose(bounds);
blast = lastmsg; /* save upper bound */
}
if (clean)
keep = t - (rcback? rcback : NDAYS) DAYS;
if (clean || bounds == NULL) { /* relocate message bounds */
struct dirent *dp;
struct stat stbuf;
bool seenany = NO;
DIR *dirp;
dirp = opendir(_PATH_MSGS);
if (dirp == NULL)
err(errno, "%s", _PATH_MSGS);
firstmsg = 32767;
lastmsg = 0;
for (dp = readdir(dirp); dp != NULL; dp = readdir(dirp)){
cp = dp->d_name;
int i = 0;
if (dp->d_ino == 0)
continue;
if (dp->d_namlen == 0)
continue;
if (clean)
snprintf(inbuf, sizeof(inbuf), "%s/%s", _PATH_MSGS, cp);
while (isdigit(*cp))
i = i * 10 + *cp++ - '0';
if (*cp)
continue; /* not a message! */
if (clean) {
if (stat(inbuf, &stbuf) != 0)
continue;
if (stbuf.st_mtime < keep
&& stbuf.st_mode&S_IWRITE) {
unlink(inbuf);
continue;
}
}
if (i > lastmsg)
lastmsg = i;
if (i < firstmsg)
firstmsg = i;
seenany = YES;
}
closedir(dirp);
if (!seenany) {
if (blast != 0) /* never lower the upper bound! */
lastmsg = blast;
firstmsg = lastmsg + 1;
}
else if (blast > lastmsg)
lastmsg = blast;
if (!send_msg) {
bounds = fopen(fname, "w");
if (bounds == NULL)
err(errno, "%s", fname);
chmod(fname, CMODE);
fprintf(bounds, "%d %d\n", firstmsg, lastmsg);
fclose(bounds);
}
}
if (send_msg) {
/*
* Send mode - place msgs in _PATH_MSGS
*/
bounds = fopen(fname, "w");
if (bounds == NULL)
err(errno, "%s", fname);
nextmsg = lastmsg + 1;
snprintf(fname, sizeof(fname), "%s/%d", _PATH_MSGS, nextmsg);
newmsg = fopen(fname, "w");
if (newmsg == NULL)
err(errno, "%s", fname);
chmod(fname, CMODE);
fprintf(bounds, "%d %d\n", firstmsg, nextmsg);
fclose(bounds);
sending = YES;
if (ruptible)
signal(SIGINT, onintr);
if (isatty(fileno(stdin))) {
ptr = getpwuid(uid)->pw_name;
printf("Message %d:\nFrom %s %sSubject: ",
nextmsg, ptr, ctime(&t));
fflush(stdout);
fgets(inbuf, sizeof inbuf, stdin);
putchar('\n');
fflush(stdout);
fprintf(newmsg, "From %s %sSubject: %s\n",
ptr, ctime(&t), inbuf);
blankline = seensubj = YES;
}
else
blankline = seensubj = NO;
for (;;) {
fgets(inbuf, sizeof inbuf, stdin);
if (feof(stdin) || ferror(stdin))
break;
blankline = (blankline || (inbuf[0] == '\n'));
seensubj = (seensubj || (!blankline && (strncmp(inbuf, "Subj", 4) == 0)));
fputs(inbuf, newmsg);
}
#ifdef OBJECT
if (!seensubj) {
printf("NOTICE: Messages should have a Subject field!\n");
#ifdef REJECT
unlink(fname);
#endif
exit(1);
}
#endif
exit(ferror(stdin));
}
if (clean)
exit(0);
/*
* prepare to display messages
*/
totty = (isatty(fileno(stdout)) != 0);
use_pager = use_pager && totty;
if ((cp = getenv("HOME")) == NULL || *cp == '\0') {
fprintf(stderr, "Error, no home directory!\n");
exit(1);
}
snprintf(fname, sizeof(fname), "%s/%s", cp, MSGSRC);
msgsrc = fopen(fname, "r");
if (msgsrc) {
newrc = NO;
fscanf(msgsrc, "%d\n", &nextmsg);
fclose(msgsrc);
if (nextmsg > lastmsg+1) {
printf("Warning: bounds have been reset (%d, %d)\n",
firstmsg, lastmsg);
truncate(fname, (off_t)0);
newrc = YES;
}
else if (!rcfirst)
rcfirst = nextmsg - rcback;
}
else
newrc = YES;
msgsrc = fopen(fname, "r+");
if (msgsrc == NULL)
msgsrc = fopen(fname, "w");
if (msgsrc == NULL)
err(errno, "%s", fname);
if (rcfirst) {
if (rcfirst > lastmsg+1) {
printf("Warning: the last message is number %d.\n",
lastmsg);
rcfirst = nextmsg;
}
if (rcfirst > firstmsg)
firstmsg = rcfirst; /* don't set below first msg */
}
if (newrc) {
nextmsg = firstmsg;
rewind(msgsrc);
fprintf(msgsrc, "%d\n", nextmsg);
fflush(msgsrc);
}
#ifdef V7
if (totty) {
struct winsize win;
if (ioctl(fileno(stdout), TIOCGWINSZ, &win) != -1)
Lpp = win.ws_row;
if (Lpp <= 0) {
if (tgetent(inbuf, getenv("TERM")) <= 0
|| (Lpp = tgetnum("li")) <= 0) {
Lpp = NLINES;
}
}
}
#endif
Lpp -= 6; /* for headers, etc. */
already = NO;
prevmsg = firstmsg;
printing = YES;
if (ruptible)
signal(SIGINT, onintr);
/*
* Main program loop
*/
for (msg = firstmsg; msg <= lastmsg; msg++) {
snprintf(fname, sizeof(fname), "%s/%d", _PATH_MSGS, msg);
newmsg = fopen(fname, "r");
if (newmsg == NULL)
continue;
gfrsub(newmsg); /* get From and Subject fields */
if (locomode && !local) {
fclose(newmsg);
continue;
}
if (qopt) { /* This has to be located here */
printf("There are new messages.\n");
exit(0);
}
if (already && !hdrs)
putchar('\n');
/*
* Print header
*/
if (totty)
signal(SIGTSTP, onsusp);
(void) setjmp(tstpbuf);
already = YES;
nlines = 2;
if (seenfrom) {
printf("Message %d:\nFrom %s %s", msg, from, date);
nlines++;
}
if (seensubj) {
printf("Subject: %s", subj);
nlines++;
}
else {
if (seenfrom) {
putchar('\n');
nlines++;
}
while (nlines < 6
&& fgets(inbuf, sizeof inbuf, newmsg)
&& inbuf[0] != '\n') {
fputs(inbuf, stdout);
nlines++;
}
}
lct = linecnt(newmsg);
if (lct)
printf("(%d%sline%s) ", lct, seensubj? " " : " more ",
(lct == 1) ? "" : "s");
if (hdrs) {
printf("\n-----\n");
fclose(newmsg);
continue;
}
/*
* Ask user for command
*/
if (totty)
ask(lct? MORE : (msg==lastmsg? NOMORE : NEXT));
else
inbuf[0] = 'y';
if (totty)
signal(SIGTSTP, SIG_DFL);
cmnd:
in = inbuf;
switch (*in) {
case 'x':
/* FALLTHROUGH */
case 'X':
exit(0);
/* NOTREACHED */
case 'q':
/* FALLTHROUGH */
case 'Q':
quitit = YES;
printf("--Postponed--\n");
exit(0);
/* NOTREACHED */
case 'n':
/* FALLTHROUGH */
case 'N':
if (msg >= nextmsg) sep = "Flushed";
prevmsg = msg;
break;
case 'p':
/* FALLTHROUGH */
case 'P':
use_pager = (*in++ == 'p');
/* FALLTHROUGH */
case '\n':
/* FALLTHROUGH */
case 'y':
default:
if (*in == '-') {
msg = prevmsg-1;
sep = "replay";
break;
}
if (isdigit(*in)) {
msg = next(in);
sep = in;
break;
}
prmesg(nlines + lct + (seensubj? 1 : 0));
prevmsg = msg;
}
printf("--%s--\n", sep);
sep = "-";
if (msg >= nextmsg) {
nextmsg = msg + 1;
rewind(msgsrc);
fprintf(msgsrc, "%d\n", nextmsg);
fflush(msgsrc);
}
if (newmsg)
fclose(newmsg);
if (quitit)
break;
}
/*
* Make sure .rc file gets updated
*/
if (--msg >= nextmsg) {
nextmsg = msg + 1;
rewind(msgsrc);
fprintf(msgsrc, "%d\n", nextmsg);
fflush(msgsrc);
}
if (already && !quitit && lastcmd && totty) {
/*
* save or reply to last message?
*/
msg = prevmsg;
ask(NOMORE);
if (inbuf[0] == '-' || isdigit(inbuf[0]))
goto cmnd;
}
if (!(already || hush || qopt))
printf("No new messages.\n");
exit(0);
/* NOTREACHED */
}
static void
usage(void)
{
fprintf(stderr, "usage: msgs [fhlopq] [[-]number]\n");
exit(1);
}
static void
prmesg(int length)
{
FILE *outf;
char *env_pager;
if (use_pager && length > Lpp) {
signal(SIGPIPE, SIG_IGN);
signal(SIGQUIT, SIG_IGN);
if ((env_pager = getenv("PAGER")) == NULL) {
snprintf(cmdbuf, sizeof(cmdbuf), _PATH_PAGER, Lpp);
} else {
snprintf(cmdbuf, sizeof(cmdbuf), "%s", env_pager);
}
outf = popen(cmdbuf, "w");
if (!outf)
outf = stdout;
else
setbuf(outf, (char *)NULL);
}
else
outf = stdout;
if (seensubj)
putc('\n', outf);
while (fgets(inbuf, sizeof inbuf, newmsg)) {
fputs(inbuf, outf);
if (ferror(outf)) {
clearerr(outf);
break;
}
}
if (outf != stdout) {
pclose(outf);
signal(SIGPIPE, SIG_DFL);
signal(SIGQUIT, SIG_DFL);
}
else {
fflush(stdout);
}
/* force wait on output */
tcdrain(fileno(stdout));
}
static void
onintr(int unused __unused)
{
signal(SIGINT, onintr);
if (mailing)
unlink(fname);
if (sending) {
unlink(fname);
puts("--Killed--");
exit(1);
}
if (printing) {
putchar('\n');
if (hdrs)
exit(0);
sep = "Interrupt";
if (newmsg)
fseeko(newmsg, (off_t)0, SEEK_END);
intrpflg = YES;
}
}
/*
* We have just gotten a susp. Suspend and prepare to resume.
*/
static void
onsusp(int unused __unused)
{
signal(SIGTSTP, SIG_DFL);
sigsetmask(0);
kill(0, SIGTSTP);
signal(SIGTSTP, onsusp);
if (!mailing)
longjmp(tstpbuf, 0);
}
static int
linecnt(FILE *f)
{
off_t oldpos = ftello(f);
int l = 0;
char lbuf[BUFSIZ];
while (fgets(lbuf, sizeof lbuf, f))
l++;
clearerr(f);
fseeko(f, oldpos, SEEK_SET);
return (l);
}
static int
next(char *buf)
{
int i;
sscanf(buf, "%d", &i);
sprintf(buf, "Goto %d", i);
return(--i);
}
static void
ask(const char *prompt)
{
char inch;
int n, cmsg, fd;
off_t oldpos;
FILE *cpfrom, *cpto;
printf("%s ", prompt);
fflush(stdout);
intrpflg = NO;
(void) fgets(inbuf, sizeof inbuf, stdin);
if ((n = strlen(inbuf)) > 0 && inbuf[n - 1] == '\n')
inbuf[n - 1] = '\0';
if (intrpflg)
inbuf[0] = 'x';
/*
* Handle 'mail' and 'save' here.
*/
if ((inch = inbuf[0]) == 's' || inch == 'm') {
if (inbuf[1] == '-')
cmsg = prevmsg;
else if (isdigit(inbuf[1]))
cmsg = atoi(&inbuf[1]);
else
cmsg = msg;
snprintf(fname, sizeof(fname), "%s/%d", _PATH_MSGS, cmsg);
oldpos = ftello(newmsg);
cpfrom = fopen(fname, "r");
if (!cpfrom) {
printf("Message %d not found\n", cmsg);
ask (prompt);
return;
}
if (inch == 's') {
in = nxtfld(inbuf);
if (*in) {
for (n=0; in[n] > ' '; n++) { /* sizeof fname? */
fname[n] = in[n];
}
fname[n] = '\0';
}
else
strcpy(fname, "Messages");
fd = open(fname, O_RDWR|O_EXCL|O_CREAT|O_APPEND);
}
else {
strcpy(fname, _PATH_TMP);
fd = mkstemp(fname);
if (fd != -1) {
snprintf(cmdbuf, sizeof(cmdbuf), _PATH_MAIL,
fname);
mailing = YES;
}
}
if (fd == -1 || (cpto = fdopen(fd, "a")) == NULL) {
if (fd != -1)
close(fd);
warn("%s", fname);
mailing = NO;
fseeko(newmsg, oldpos, SEEK_SET);
ask(prompt);
return;
}
while ((n = fread(inbuf, 1, sizeof inbuf, cpfrom)))
fwrite(inbuf, 1, n, cpto);
fclose(cpfrom);
fclose(cpto);
fseeko(newmsg, oldpos, SEEK_SET);/* reposition current message */
if (inch == 's')
printf("Message %d saved in \"%s\"\n", cmsg, fname);
else {
system(cmdbuf);
unlink(fname);
mailing = NO;
}
ask(prompt);
}
}
static void
gfrsub(FILE *infile)
{
off_t frompos;
int count;
seensubj = seenfrom = NO;
local = YES;
subj[0] = from[0] = date[0] = '\0';
/*
* Is this a normal message?
*/
if (fgets(inbuf, sizeof inbuf, infile)) {
if (strncmp(inbuf, "From", 4)==0) {
/*
* expected form starts with From
*/
seenfrom = YES;
frompos = ftello(infile);
ptr = from;
in = nxtfld(inbuf);
if (*in) {
count = sizeof(from) - 1;
while (*in && *in > ' ' && count-- > 0) {
if (*in == ':' || *in == '@' ||
*in == '!')
local = NO;
*ptr++ = *in++;
}
}
*ptr = '\0';
if (*(in = nxtfld(in)))
strlcpy(date, in, sizeof date);
else {
date[0] = '\n';
date[1] = '\0';
}
}
else {
/*
* not the expected form
*/
rewind(infile);
return;
}
}
else
/*
* empty file ?
*/
return;
/*
* look for Subject line until EOF or a blank line
*/
while (fgets(inbuf, sizeof inbuf, infile)
&& !(blankline = (inbuf[0] == '\n'))) {
/*
* extract Subject line
*/
if (!seensubj && strncmp(inbuf, "Subj", 4)==0) {
seensubj = YES;
frompos = ftello(infile);
strlcpy(subj, nxtfld(inbuf), sizeof subj);
}
}
if (!blankline)
/*
* ran into EOF
*/
fseeko(infile, frompos, SEEK_SET);
if (!seensubj)
/*
* for possible use with Mail
*/
strlcpy(subj, "(No Subject)\n", sizeof subj);
}
static char *
nxtfld(char *s)
{
if (*s) while (*s && !isspace(*s)) s++; /* skip over this field */
if (*s) while (*s && isspace(*s)) s++; /* find start of next field */
return (s);
}