FreeBSD-5.3/sbin/savecore/savecore.c
/*-
* Copyright (c) 2002 Poul-Henning Kamp
* Copyright (c) 2002 Networks Associates Technology, Inc.
* All rights reserved.
*
* This software was developed for the FreeBSD Project by Poul-Henning Kamp
* and NAI Labs, the Security Research Division of Network Associates, Inc.
* under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the
* DARPA CHATS research program.
*
* 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. The names of the authors may not be used to endorse or promote
* products derived from this software without specific prior written
* permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
*
* Copyright (c) 1986, 1992, 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD: src/sbin/savecore/savecore.c,v 1.69 2004/08/16 07:02:14 ru Exp $");
#include <sys/param.h>
#include <sys/disk.h>
#include <sys/kerneldump.h>
#include <sys/param.h>
#include <sys/mount.h>
#include <sys/stat.h>
#include <errno.h>
#include <fcntl.h>
#include <fstab.h>
#include <paths.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <time.h>
#include <unistd.h>
/* The size of the buffer used for I/O. */
#define BUFFERSIZE (1024*1024)
static int checkfor, compress, clear, force, keep, verbose; /* flags */
static int nfound, nsaved, nerr; /* statistics */
extern FILE *zopen(const char *, const char *);
static void
printheader(FILE *f, const struct kerneldumpheader *h, const char *device,
int bounds)
{
uint64_t dumplen;
time_t t;
fprintf(f, "Good dump found on device %s\n", device);
fprintf(f, " Architecture: %s\n", h->architecture);
fprintf(f, " Architecture version: %d\n",
dtoh32(h->architectureversion));
dumplen = dtoh64(h->dumplength);
fprintf(f, " Dump length: %lldB (%lld MB)\n", (long long)dumplen,
(long long)(dumplen >> 20));
fprintf(f, " Blocksize: %d\n", dtoh32(h->blocksize));
t = dtoh64(h->dumptime);
fprintf(f, " Dumptime: %s", ctime(&t));
fprintf(f, " Hostname: %s\n", h->hostname);
fprintf(f, " Versionstring: %s", h->versionstring);
fprintf(f, " Panicstring: %s\n", h->panicstring);
fprintf(f, " Bounds: %d\n", bounds);
fflush(f);
}
static int
getbounds(void) {
FILE *fp;
char buf[6];
int ret;
ret = 0;
if ((fp = fopen("bounds", "r")) == NULL) {
syslog(LOG_WARNING, "unable to open bounds file, using 0");
goto newfile;
}
if (fgets(buf, sizeof buf, fp) == NULL) {
syslog(LOG_WARNING, "unable to read from bounds, using 0");
fclose(fp);
goto newfile;
}
errno = 0;
ret = (int)strtol(buf, NULL, 10);
if (ret == 0 && (errno == EINVAL || errno == ERANGE))
syslog(LOG_WARNING, "invalid value found in bounds, using 0");
newfile:
if ((fp = fopen("bounds", "w")) == NULL) {
syslog(LOG_WARNING, "unable to write to bounds file: %m");
goto done;
}
if (verbose)
printf("bounds number: %d\n", ret);
fprintf(fp, "%d\n", (ret + 1));
fclose(fp);
done:
return (ret);
}
/*
* Check that sufficient space is available on the disk that holds the
* save directory.
*/
static int
check_space(char *savedir, off_t dumpsize)
{
FILE *fp;
off_t minfree, spacefree, totfree, needed;
struct statfs fsbuf;
char buf[100], path[MAXPATHLEN];
if (statfs(savedir, &fsbuf) < 0) {
syslog(LOG_ERR, "%s: %m", savedir);
exit(1);
}
spacefree = ((off_t) fsbuf.f_bavail * fsbuf.f_bsize) / 1024;
totfree = ((off_t) fsbuf.f_bfree * fsbuf.f_bsize) / 1024;
(void)snprintf(path, sizeof(path), "%s/minfree", savedir);
if ((fp = fopen(path, "r")) == NULL)
minfree = 0;
else {
if (fgets(buf, sizeof(buf), fp) == NULL)
minfree = 0;
else
minfree = atoi(buf);
(void)fclose(fp);
}
needed = dumpsize / 1024 + 2; /* 2 for info file */
if (((minfree > 0) ? spacefree : totfree) - needed < minfree) {
syslog(LOG_WARNING,
"no dump, not enough free space on device (%lld available, need %lld)",
(long long)(minfree > 0 ? spacefree : totfree),
(long long)needed);
return (0);
}
if (spacefree - needed < 0)
syslog(LOG_WARNING,
"dump performed, but free space threshold crossed");
return (1);
}
#define BLOCKSIZE (1<<12)
#define BLOCKMASK (~(BLOCKSIZE-1))
static void
DoFile(char *savedir, const char *device)
{
static char *buf = NULL;
struct kerneldumpheader kdhf, kdhl;
off_t mediasize, dumpsize, firsthd, lasthd, dmpcnt;
FILE *info, *fp;
int fd, fdinfo, error, wl;
int nr, nw, hs, he;
int bounds;
u_int sectorsize;
mode_t oumask;
dmpcnt = 0;
mediasize = 0;
if (buf == NULL) {
buf = malloc(BUFFERSIZE);
if (buf == NULL) {
syslog(LOG_ERR, "%m");
return;
}
}
if (verbose)
printf("checking for kernel dump on device %s\n", device);
fd = open(device, O_RDWR);
if (fd < 0) {
syslog(LOG_ERR, "%s: %m", device);
return;
}
error = ioctl(fd, DIOCGMEDIASIZE, &mediasize);
if (!error)
error = ioctl(fd, DIOCGSECTORSIZE, §orsize);
if (error) {
syslog(LOG_ERR,
"couldn't find media and/or sector size of %s: %m", device);
goto closefd;
}
if (verbose) {
printf("mediasize = %lld\n", (long long)mediasize);
printf("sectorsize = %u\n", sectorsize);
}
lasthd = mediasize - sectorsize;
lseek(fd, lasthd, SEEK_SET);
error = read(fd, &kdhl, sizeof kdhl);
if (error != sizeof kdhl) {
syslog(LOG_ERR,
"error reading last dump header at offset %lld in %s: %m",
(long long)lasthd, device);
goto closefd;
}
if (memcmp(kdhl.magic, KERNELDUMPMAGIC, sizeof kdhl.magic)) {
if (verbose)
printf("magic mismatch on last dump header on %s\n",
device);
if (force == 0)
goto closefd;
if (memcmp(kdhl.magic, KERNELDUMPMAGIC_CLEARED,
sizeof kdhl.magic) == 0) {
if (verbose)
printf("forcing magic on %s\n", device);
memcpy(kdhl.magic, KERNELDUMPMAGIC,
sizeof kdhl.magic);
} else {
syslog(LOG_ERR, "unable to force dump - bad magic");
goto closefd;
}
}
if (dtoh32(kdhl.version) != KERNELDUMPVERSION) {
syslog(LOG_ERR,
"unknown version (%d) in last dump header on %s",
dtoh32(kdhl.version), device);
goto closefd;
}
nfound++;
if (clear)
goto nuke;
if (kerneldump_parity(&kdhl)) {
syslog(LOG_ERR,
"parity error on last dump header on %s", device);
nerr++;
goto closefd;
}
dumpsize = dtoh64(kdhl.dumplength);
firsthd = lasthd - dumpsize - sizeof kdhf;
lseek(fd, firsthd, SEEK_SET);
error = read(fd, &kdhf, sizeof kdhf);
if (error != sizeof kdhf) {
syslog(LOG_ERR,
"error reading first dump header at offset %lld in %s: %m",
(long long)firsthd, device);
nerr++;
goto closefd;
}
if (memcmp(&kdhl, &kdhf, sizeof kdhl)) {
syslog(LOG_ERR,
"first and last dump headers disagree on %s", device);
nerr++;
goto closefd;
}
if (checkfor) {
printf("A dump exists on %s\n", device);
close(fd);
exit(0);
}
if (kdhl.panicstring[0])
syslog(LOG_ALERT, "reboot after panic: %s", kdhl.panicstring);
else
syslog(LOG_ALERT, "reboot");
if (verbose)
printf("Checking for available free space\n");
if (!check_space(savedir, dumpsize)) {
nerr++;
goto closefd;
}
bounds = getbounds();
sprintf(buf, "info.%d", bounds);
/*
* Create or overwrite any existing files.
*/
fdinfo = open(buf, O_WRONLY | O_CREAT | O_TRUNC, 0600);
if (fdinfo < 0) {
syslog(LOG_ERR, "%s: %m", buf);
nerr++;
goto closefd;
}
oumask = umask(S_IRWXG|S_IRWXO); /* Restrict access to the core file.*/
if (compress) {
sprintf(buf, "vmcore.%d.gz", bounds);
fp = zopen(buf, "w");
} else {
sprintf(buf, "vmcore.%d", bounds);
fp = fopen(buf, "w");
}
if (fp == NULL) {
syslog(LOG_ERR, "%s: %m", buf);
close(fdinfo);
nerr++;
goto closefd;
}
(void)umask(oumask);
info = fdopen(fdinfo, "w");
if (verbose)
printheader(stdout, &kdhl, device, bounds);
printheader(info, &kdhl, device, bounds);
fclose(info);
syslog(LOG_NOTICE, "writing %score to %s",
compress ? "compressed " : "", buf);
while (dumpsize > 0) {
wl = BUFFERSIZE;
if (wl > dumpsize)
wl = dumpsize;
nr = read(fd, buf, wl);
if (nr != wl) {
if (nr == 0)
syslog(LOG_WARNING,
"WARNING: EOF on dump device");
else
syslog(LOG_ERR, "read error on %s: %m", device);
nerr++;
goto closeall;
}
if (compress) {
nw = fwrite(buf, 1, wl, fp);
} else {
for (nw = 0; nw < nr; nw = he) {
/* find a contiguous block of zeroes */
for (hs = nw; hs < nr; hs += BLOCKSIZE) {
for (he = hs; he < nr && buf[he] == 0; ++he)
/* nothing */ ;
/* is the hole long enough to matter? */
if (he >= hs + BLOCKSIZE)
break;
}
/* back down to a block boundary */
he &= BLOCKMASK;
/*
* 1) Don't go beyond the end of the buffer.
* 2) If the end of the buffer is less than
* BLOCKSIZE bytes away, we're at the end
* of the file, so just grab what's left.
*/
if (hs + BLOCKSIZE > nr)
hs = he = nr;
/*
* At this point, we have a partial ordering:
* nw <= hs <= he <= nr
* If hs > nw, buf[nw..hs] contains non-zero data.
* If he > hs, buf[hs..he] is all zeroes.
*/
if (hs > nw)
if (fwrite(buf + nw, hs - nw, 1, fp) != 1)
break;
if (he > hs)
if (fseeko(fp, he - hs, SEEK_CUR) == -1)
break;
}
}
if (nw != wl) {
syslog(LOG_ERR,
"write error on vmcore.%d file: %m", bounds);
syslog(LOG_WARNING,
"WARNING: vmcore may be incomplete");
nerr++;
goto closeall;
}
if (verbose) {
dmpcnt += wl;
printf("%llu\r", (unsigned long long)dmpcnt);
fflush(stdout);
}
dumpsize -= wl;
}
if (verbose)
printf("\n");
if (fclose(fp) < 0) {
syslog(LOG_ERR, "error on vmcore.%d: %m", bounds);
nerr++;
goto closeall;
}
nsaved++;
if (verbose)
printf("dump saved\n");
nuke:
if (clear || !keep) {
if (verbose)
printf("clearing dump header\n");
memcpy(kdhl.magic, KERNELDUMPMAGIC_CLEARED, sizeof kdhl.magic);
lseek(fd, lasthd, SEEK_SET);
error = write(fd, &kdhl, sizeof kdhl);
if (error != sizeof kdhl)
syslog(LOG_ERR,
"error while clearing the dump header: %m");
}
close(fd);
return;
closeall:
fclose(fp);
closefd:
close(fd);
}
static void
usage(void)
{
fprintf(stderr,
"usage: savecore [-Cv|-cfkvz] [directory [device...]]\n");
exit (1);
}
int
main(int argc, char **argv)
{
int i, ch, error;
struct fstab *fsp;
char *savedir;
openlog("savecore", LOG_PERROR, LOG_DAEMON);
savedir = strdup(".");
if (savedir == NULL) {
syslog(LOG_ERR, "Cannot allocate memory");
exit(1);
}
while ((ch = getopt(argc, argv, "Ccfkvz")) != -1)
switch(ch) {
case 'C':
checkfor = 1;
break;
case 'c':
clear = 1;
break;
case 'k':
keep = 1;
break;
case 'v':
verbose = 1;
break;
case 'f':
force = 1;
break;
case 'z':
compress = 1;
break;
case '?':
default:
usage();
}
if (checkfor && (clear || force || keep))
usage();
argc -= optind;
argv += optind;
if (argc >= 1) {
error = chdir(argv[0]);
if (error) {
syslog(LOG_ERR, "chdir(%s): %m", argv[0]);
exit(1);
}
savedir = argv[0];
argc--;
argv++;
}
if (argc == 0) {
for (;;) {
fsp = getfsent();
if (fsp == NULL)
break;
if (strcmp(fsp->fs_vfstype, "swap") &&
strcmp(fsp->fs_vfstype, "dump"))
continue;
DoFile(savedir, fsp->fs_spec);
}
} else {
for (i = 0; i < argc; i++)
DoFile(savedir, argv[i]);
}
/* Emit minimal output. */
if (nfound == 0) {
if (checkfor) {
printf("No dump exists\n");
exit(1);
}
syslog(LOG_WARNING, "no dumps found");
}
else if (nsaved == 0) {
if (nerr != 0)
syslog(LOG_WARNING, "unsaved dumps found but not saved");
else
syslog(LOG_WARNING, "no unsaved dumps found");
}
return (0);
}