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33 KiB

/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* 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. 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("$FreeBSD$");
#include <sys/param.h>
#include <sys/disk.h>
#include <sys/kerneldump.h>
#include <sys/mount.h>
#include <sys/stat.h>
#include <capsicum_helpers.h>
#include <ctype.h>
#include <errno.h>
#include <fcntl.h>
#include <fstab.h>
#include <paths.h>
#include <signal.h>
#include <stdarg.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <syslog.h>
#include <time.h>
#include <unistd.h>
#define Z_SOLO
#include <zlib.h>
#include <zstd.h>
#include <libcasper.h>
#include <casper/cap_fileargs.h>
#include <casper/cap_syslog.h>
#include <libxo/xo.h>
/* The size of the buffer used for I/O. */
#define BUFFERSIZE (1024*1024)
#define STATUS_BAD 0
#define STATUS_GOOD 1
#define STATUS_UNKNOWN 2
static cap_channel_t *capsyslog;
static fileargs_t *capfa;
static bool checkfor, compress, uncompress, clear, force, keep; /* flags */
static int verbose;
static int nfound, nsaved, nerr; /* statistics */
static int maxdumps;
extern FILE *zdopen(int, const char *);
static sig_atomic_t got_siginfo;
static void infohandler(int);
static void
logmsg(int pri, const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
if (capsyslog != NULL)
cap_vsyslog(capsyslog, pri, fmt, ap);
else
vsyslog(pri, fmt, ap);
va_end(ap);
}
static FILE *
xfopenat(int dirfd, const char *path, int flags, const char *modestr, ...)
{
va_list ap;
FILE *fp;
mode_t mode;
int error, fd;
if ((flags & O_CREAT) == O_CREAT) {
va_start(ap, modestr);
mode = (mode_t)va_arg(ap, int);
va_end(ap);
} else
mode = 0;
fd = openat(dirfd, path, flags, mode);
if (fd < 0)
return (NULL);
fp = fdopen(fd, modestr);
if (fp == NULL) {
error = errno;
(void)close(fd);
errno = error;
}
return (fp);
}
static void
printheader(xo_handle_t *xo, const struct kerneldumpheader *h,
const char *device, int bounds, const int status)
{
uint64_t dumplen;
time_t t;
struct tm tm;
char time_str[64];
const char *stat_str;
const char *comp_str;
xo_flush_h(xo);
xo_emit_h(xo, "{Lwc:Dump header from device}{:dump_device/%s}\n",
device);
xo_emit_h(xo, "{P: }{Lwc:Architecture}{:architecture/%s}\n",
h->architecture);
xo_emit_h(xo,
"{P: }{Lwc:Architecture Version}{:architecture_version/%u}\n",
dtoh32(h->architectureversion));
dumplen = dtoh64(h->dumplength);
xo_emit_h(xo, "{P: }{Lwc:Dump Length}{:dump_length_bytes/%lld}\n",
(long long)dumplen);
xo_emit_h(xo, "{P: }{Lwc:Blocksize}{:blocksize/%d}\n",
dtoh32(h->blocksize));
switch (h->compression) {
case KERNELDUMP_COMP_NONE:
comp_str = "none";
break;
case KERNELDUMP_COMP_GZIP:
comp_str = "gzip";
break;
case KERNELDUMP_COMP_ZSTD:
comp_str = "zstd";
break;
default:
comp_str = "???";
break;
}
xo_emit_h(xo, "{P: }{Lwc:Compression}{:compression/%s}\n", comp_str);
t = dtoh64(h->dumptime);
localtime_r(&t, &tm);
if (strftime(time_str, sizeof(time_str), "%F %T %z", &tm) == 0)
time_str[0] = '\0';
xo_emit_h(xo, "{P: }{Lwc:Dumptime}{:dumptime/%s}\n", time_str);
xo_emit_h(xo, "{P: }{Lwc:Hostname}{:hostname/%s}\n", h->hostname);
xo_emit_h(xo, "{P: }{Lwc:Magic}{:magic/%s}\n", h->magic);
xo_emit_h(xo, "{P: }{Lwc:Version String}{:version_string/%s}",
h->versionstring);
xo_emit_h(xo, "{P: }{Lwc:Panic String}{:panic_string/%s}\n",
h->panicstring);
xo_emit_h(xo, "{P: }{Lwc:Dump Parity}{:dump_parity/%u}\n", h->parity);
xo_emit_h(xo, "{P: }{Lwc:Bounds}{:bounds/%d}\n", bounds);
switch (status) {
case STATUS_BAD:
stat_str = "bad";
break;
case STATUS_GOOD:
stat_str = "good";
break;
default:
stat_str = "unknown";
break;
}
xo_emit_h(xo, "{P: }{Lwc:Dump Status}{:dump_status/%s}\n", stat_str);
xo_flush_h(xo);
}
static int
getbounds(int savedirfd)
{
FILE *fp;
char buf[6];
int ret;
/*
* If we are just checking, then we haven't done a chdir to the dump
* directory and we should not try to read a bounds file.
*/
if (checkfor)
return (0);
ret = 0;
if ((fp = xfopenat(savedirfd, "bounds", O_RDONLY, "r")) == NULL) {
if (verbose)
printf("unable to open bounds file, using 0\n");
return (ret);
}
if (fgets(buf, sizeof(buf), fp) == NULL) {
if (feof(fp))
logmsg(LOG_WARNING, "bounds file is empty, using 0");
else
logmsg(LOG_WARNING, "bounds file: %s", strerror(errno));
fclose(fp);
return (ret);
}
errno = 0;
ret = (int)strtol(buf, NULL, 10);
if (ret == 0 && (errno == EINVAL || errno == ERANGE))
logmsg(LOG_WARNING, "invalid value found in bounds, using 0");
fclose(fp);
return (ret);
}
static void
writebounds(int savedirfd, int bounds)
{
FILE *fp;
if ((fp = xfopenat(savedirfd, "bounds", O_WRONLY | O_CREAT | O_TRUNC,
"w", 0644)) == NULL) {
logmsg(LOG_WARNING, "unable to write to bounds file: %m");
return;
}
if (verbose)
printf("bounds number: %d\n", bounds);
fprintf(fp, "%d\n", bounds);
fclose(fp);
}
static bool
writekey(int savedirfd, const char *keyname, uint8_t *dumpkey,
uint32_t dumpkeysize)
{
int fd;
fd = openat(savedirfd, keyname, O_WRONLY | O_CREAT | O_TRUNC, 0600);
if (fd == -1) {
logmsg(LOG_ERR, "Unable to open %s to write the key: %m.",
keyname);
return (false);
}
if (write(fd, dumpkey, dumpkeysize) != (ssize_t)dumpkeysize) {
logmsg(LOG_ERR, "Unable to write the key to %s: %m.", keyname);
close(fd);
return (false);
}
close(fd);
return (true);
}
static off_t
file_size(int savedirfd, const char *path)
{
struct stat sb;
/* Ignore all errors, this file may not exist. */
if (fstatat(savedirfd, path, &sb, 0) == -1)
return (0);
return (sb.st_size);
}
static off_t
saved_dump_size(int savedirfd, int bounds)
{
static char path[PATH_MAX];
off_t dumpsize;
dumpsize = 0;
(void)snprintf(path, sizeof(path), "info.%d", bounds);
dumpsize += file_size(savedirfd, path);
(void)snprintf(path, sizeof(path), "vmcore.%d", bounds);
dumpsize += file_size(savedirfd, path);
(void)snprintf(path, sizeof(path), "vmcore.%d.gz", bounds);
dumpsize += file_size(savedirfd, path);
(void)snprintf(path, sizeof(path), "vmcore.%d.zst", bounds);
dumpsize += file_size(savedirfd, path);
(void)snprintf(path, sizeof(path), "textdump.tar.%d", bounds);
dumpsize += file_size(savedirfd, path);
(void)snprintf(path, sizeof(path), "textdump.tar.%d.gz", bounds);
dumpsize += file_size(savedirfd, path);
return (dumpsize);
}
static void
saved_dump_remove(int savedirfd, int bounds)
{
static char path[PATH_MAX];
(void)snprintf(path, sizeof(path), "info.%d", bounds);
(void)unlinkat(savedirfd, path, 0);
(void)snprintf(path, sizeof(path), "vmcore.%d", bounds);
(void)unlinkat(savedirfd, path, 0);
(void)snprintf(path, sizeof(path), "vmcore.%d.gz", bounds);
(void)unlinkat(savedirfd, path, 0);
(void)snprintf(path, sizeof(path), "vmcore.%d.zst", bounds);
(void)unlinkat(savedirfd, path, 0);
(void)snprintf(path, sizeof(path), "textdump.tar.%d", bounds);
(void)unlinkat(savedirfd, path, 0);
(void)snprintf(path, sizeof(path), "textdump.tar.%d.gz", bounds);
(void)unlinkat(savedirfd, path, 0);
}
static void
symlinks_remove(int savedirfd)
{
(void)unlinkat(savedirfd, "info.last", 0);
(void)unlinkat(savedirfd, "key.last", 0);
(void)unlinkat(savedirfd, "vmcore.last", 0);
(void)unlinkat(savedirfd, "vmcore.last.gz", 0);
(void)unlinkat(savedirfd, "vmcore.last.zst", 0);
(void)unlinkat(savedirfd, "vmcore_encrypted.last", 0);
(void)unlinkat(savedirfd, "vmcore_encrypted.last.gz", 0);
(void)unlinkat(savedirfd, "textdump.tar.last", 0);
(void)unlinkat(savedirfd, "textdump.tar.last.gz", 0);
}
/*
* Check that sufficient space is available on the disk that holds the
* save directory.
*/
static int
check_space(const char *savedir, int savedirfd, off_t dumpsize, int bounds)
{
char buf[100];
struct statfs fsbuf;
FILE *fp;
off_t available, minfree, spacefree, totfree, needed;
if (fstatfs(savedirfd, &fsbuf) < 0) {
logmsg(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;
if ((fp = xfopenat(savedirfd, "minfree", O_RDONLY, "r")) == NULL)
minfree = 0;
else {
if (fgets(buf, sizeof(buf), fp) == NULL)
minfree = 0;
else {
char *endp;
errno = 0;
minfree = strtoll(buf, &endp, 10);
if (minfree == 0 && errno != 0)
minfree = -1;
else {
while (*endp != '\0' && isspace(*endp))
endp++;
if (*endp != '\0' || minfree < 0)
minfree = -1;
}
if (minfree < 0)
logmsg(LOG_WARNING,
"`minfree` didn't contain a valid size "
"(`%s`). Defaulting to 0", buf);
}
(void)fclose(fp);
}
available = minfree > 0 ? spacefree - minfree : totfree;
needed = dumpsize / 1024 + 2; /* 2 for info file */
needed -= saved_dump_size(savedirfd, bounds);
if (available < needed) {
logmsg(LOG_WARNING,
"no dump: not enough free space on device (need at least "
"%jdkB for dump; %jdkB available; %jdkB reserved)",
(intmax_t)needed,
(intmax_t)available + minfree,
(intmax_t)minfree);
return (0);
}
if (spacefree - needed < 0)
logmsg(LOG_WARNING,
"dump performed, but free space threshold crossed");
return (1);
}
static bool
compare_magic(const struct kerneldumpheader *kdh, const char *magic)
{
return (strncmp(kdh->magic, magic, sizeof(kdh->magic)) == 0);
}
#define BLOCKSIZE (1<<12)
#define BLOCKMASK (~(BLOCKSIZE-1))
static size_t
sparsefwrite(const char *buf, size_t nr, FILE *fp)
{
size_t nw, he, hs;
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;
}
return (nw);
}
static char *zbuf;
static size_t zbufsize;
static ssize_t
GunzipWrite(z_stream *z, char *in, size_t insize, FILE *fp)
{
static bool firstblock = true; /* XXX not re-entrable/usable */
const size_t hdrlen = 10;
size_t nw = 0, w;
int rv;
z->next_in = in;
z->avail_in = insize;
/*
* Since contrib/zlib for some reason is compiled
* without GUNZIP define, we need to skip the gzip
* header manually. Kernel puts minimal 10 byte
* header, see sys/kern/subr_compressor.c:gz_reset().
*/
if (firstblock) {
z->next_in += hdrlen;
z->avail_in -= hdrlen;
firstblock = false;
}
do {
z->next_out = zbuf;
z->avail_out = zbufsize;
rv = inflate(z, Z_NO_FLUSH);
if (rv != Z_OK && rv != Z_STREAM_END) {
logmsg(LOG_ERR, "decompression failed: %s", z->msg);
return (-1);
}
w = sparsefwrite(zbuf, zbufsize - z->avail_out, fp);
if (w < zbufsize - z->avail_out)
return (-1);
nw += w;
} while (z->avail_in > 0 && rv != Z_STREAM_END);
return (nw);
}
static ssize_t
ZstdWrite(ZSTD_DCtx *Zctx, char *in, size_t insize, FILE *fp)
{
ZSTD_inBuffer Zin;
ZSTD_outBuffer Zout;
size_t nw = 0, w;
int rv;
Zin.src = in;
Zin.size = insize;
Zin.pos = 0;
do {
Zout.dst = zbuf;
Zout.size = zbufsize;
Zout.pos = 0;
rv = ZSTD_decompressStream(Zctx, &Zout, &Zin);
if (ZSTD_isError(rv)) {
logmsg(LOG_ERR, "decompression failed: %s",
ZSTD_getErrorName(rv));
return (-1);
}
w = sparsefwrite(zbuf, Zout.pos, fp);
if (w < Zout.pos)
return (-1);
nw += w;
} while (Zin.pos < Zin.size && rv != 0);
return (nw);
}
static int
DoRegularFile(int fd, off_t dumpsize, u_int sectorsize, bool sparse,
uint8_t compression, char *buf, const char *device,
const char *filename, FILE *fp)
{
size_t nr, wl;
ssize_t nw;
off_t dmpcnt, origsize;
z_stream z; /* gzip */
ZSTD_DCtx *Zctx; /* zstd */
dmpcnt = 0;
origsize = dumpsize;
if (compression == KERNELDUMP_COMP_GZIP) {
memset(&z, 0, sizeof(z));
z.zalloc = Z_NULL;
z.zfree = Z_NULL;
if (inflateInit2(&z, -MAX_WBITS) != Z_OK) {
logmsg(LOG_ERR, "failed to initialize zlib: %s", z.msg);
return (-1);
}
zbufsize = BUFFERSIZE;
} else if (compression == KERNELDUMP_COMP_ZSTD) {
if ((Zctx = ZSTD_createDCtx()) == NULL) {
logmsg(LOG_ERR, "failed to initialize zstd");
return (-1);
}
zbufsize = ZSTD_DStreamOutSize();
}
if (zbufsize > 0)
if ((zbuf = malloc(zbufsize)) == NULL) {
logmsg(LOG_ERR, "failed to alloc decompression buffer");
return (-1);
}
while (dumpsize > 0) {
wl = BUFFERSIZE;
if (wl > (size_t)dumpsize)
wl = dumpsize;
nr = read(fd, buf, roundup(wl, sectorsize));
if (nr != roundup(wl, sectorsize)) {
if (nr == 0)
logmsg(LOG_WARNING,
"WARNING: EOF on dump device");
else
logmsg(LOG_ERR, "read error on %s: %m", device);
nerr++;
return (-1);
}
if (compression == KERNELDUMP_COMP_GZIP)
nw = GunzipWrite(&z, buf, nr, fp);
else if (compression == KERNELDUMP_COMP_ZSTD)
nw = ZstdWrite(Zctx, buf, nr, fp);
else if (!sparse)
nw = fwrite(buf, 1, wl, fp);
else
nw = sparsefwrite(buf, wl, fp);
if (nw < 0 || (compression == KERNELDUMP_COMP_NONE &&
(size_t)nw != wl)) {
logmsg(LOG_ERR,
"write error on %s file: %m", filename);
logmsg(LOG_WARNING,
"WARNING: vmcore may be incomplete");
nerr++;
return (-1);
}
if (verbose) {
dmpcnt += wl;
printf("%llu\r", (unsigned long long)dmpcnt);
fflush(stdout);
}
dumpsize -= wl;
if (got_siginfo) {
printf("%s %.1lf%%\n", filename, (100.0 - (100.0 *
(double)dumpsize / (double)origsize)));
got_siginfo = 0;
}
}
return (0);
}
/*
* Specialized version of dump-reading logic for use with textdumps, which
* are written backwards from the end of the partition, and must be reversed
* before being written to the file. Textdumps are small, so do a bit less
* work to optimize/sparsify.
*/
static int
DoTextdumpFile(int fd, off_t dumpsize, off_t lasthd, char *buf,
const char *device, const char *filename, FILE *fp)
{
int nr, nw, wl;
off_t dmpcnt, totsize;
totsize = dumpsize;
dmpcnt = 0;
wl = 512;
if ((dumpsize % wl) != 0) {
logmsg(LOG_ERR, "textdump uneven multiple of 512 on %s",
device);
nerr++;
return (-1);
}
while (dumpsize > 0) {
nr = pread(fd, buf, wl, lasthd - (totsize - dumpsize) - wl);
if (nr != wl) {
if (nr == 0)
logmsg(LOG_WARNING,
"WARNING: EOF on dump device");
else
logmsg(LOG_ERR, "read error on %s: %m", device);
nerr++;
return (-1);
}
nw = fwrite(buf, 1, wl, fp);
if (nw != wl) {
logmsg(LOG_ERR,
"write error on %s file: %m", filename);
logmsg(LOG_WARNING,
"WARNING: textdump may be incomplete");
nerr++;
return (-1);
}
if (verbose) {
dmpcnt += wl;
printf("%llu\r", (unsigned long long)dmpcnt);
fflush(stdout);
}
dumpsize -= wl;
}
return (0);
}
static void
DoFile(const char *savedir, int savedirfd, const char *device)
{
xo_handle_t *xostdout, *xoinfo;
static char infoname[PATH_MAX], corename[PATH_MAX], linkname[PATH_MAX];
static char keyname[PATH_MAX];
static char *buf = NULL;
char *temp = NULL;
struct kerneldumpheader kdhf, kdhl;
uint8_t *dumpkey;
off_t mediasize, dumpextent, dumplength, firsthd, lasthd;
FILE *core, *info;
int fdcore, fddev, error;
int bounds, status;
u_int sectorsize, xostyle;
uint32_t dumpkeysize;
bool iscompressed, isencrypted, istextdump, ret;
bounds = getbounds(savedirfd);
dumpkey = NULL;
mediasize = 0;
status = STATUS_UNKNOWN;
xostdout = xo_create_to_file(stdout, XO_STYLE_TEXT, 0);
if (xostdout == NULL) {
logmsg(LOG_ERR, "%s: %m", infoname);
return;
}
if (maxdumps > 0 && bounds == maxdumps)
bounds = 0;
if (buf == NULL) {
buf = malloc(BUFFERSIZE);
if (buf == NULL) {
logmsg(LOG_ERR, "%m");
return;
}
}
if (verbose)
printf("checking for kernel dump on device %s\n", device);
fddev = fileargs_open(capfa, device);
if (fddev < 0) {
logmsg(LOG_ERR, "%s: %m", device);
return;
}
error = ioctl(fddev, DIOCGMEDIASIZE, &mediasize);
if (!error)
error = ioctl(fddev, DIOCGSECTORSIZE, &sectorsize);
if (error) {
logmsg(LOG_ERR,
"couldn't find media and/or sector size of %s: %m", device);
goto closefd;
}
if (verbose) {
printf("mediasize = %lld bytes\n", (long long)mediasize);
printf("sectorsize = %u bytes\n", sectorsize);
}
if (sectorsize < sizeof(kdhl)) {
logmsg(LOG_ERR,
"Sector size is less the kernel dump header %zu",
sizeof(kdhl));
goto closefd;
}
lasthd = mediasize - sectorsize;
temp = malloc(sectorsize);
if (temp == NULL) {
logmsg(LOG_ERR, "%m");
goto closefd;
}
if (lseek(fddev, lasthd, SEEK_SET) != lasthd ||
read(fddev, temp, sectorsize) != (ssize_t)sectorsize) {
logmsg(LOG_ERR,
"error reading last dump header at offset %lld in %s: %m",
(long long)lasthd, device);
goto closefd;
}
memcpy(&kdhl, temp, sizeof(kdhl));
iscompressed = istextdump = false;
if (compare_magic(&kdhl, TEXTDUMPMAGIC)) {
if (verbose)
printf("textdump magic on last dump header on %s\n",
device);
istextdump = true;
if (dtoh32(kdhl.version) != KERNELDUMP_TEXT_VERSION) {
logmsg(LOG_ERR,
"unknown version (%d) in last dump header on %s",
dtoh32(kdhl.version), device);
status = STATUS_BAD;
if (!force)
goto closefd;
}
} else if (compare_magic(&kdhl, KERNELDUMPMAGIC)) {
if (dtoh32(kdhl.version) != KERNELDUMPVERSION) {
logmsg(LOG_ERR,
"unknown version (%d) in last dump header on %s",
dtoh32(kdhl.version), device);
status = STATUS_BAD;
if (!force)
goto closefd;
}
switch (kdhl.compression) {
case KERNELDUMP_COMP_NONE:
uncompress = false;
break;
case KERNELDUMP_COMP_GZIP:
case KERNELDUMP_COMP_ZSTD:
if (compress && verbose)
printf("dump is already compressed\n");
if (uncompress && verbose)
printf("dump to be uncompressed\n");
compress = false;
iscompressed = true;
break;
default:
logmsg(LOG_ERR, "unknown compression type %d on %s",
kdhl.compression, device);
break;
}
} else {
if (verbose)
printf("magic mismatch on last dump header on %s\n",
device);
status = STATUS_BAD;
if (!force)
goto closefd;
if (compare_magic(&kdhl, KERNELDUMPMAGIC_CLEARED)) {
if (verbose)
printf("forcing magic on %s\n", device);
memcpy(kdhl.magic, KERNELDUMPMAGIC, sizeof(kdhl.magic));
} else {
logmsg(LOG_ERR, "unable to force dump - bad magic");
goto closefd;
}
if (dtoh32(kdhl.version) != KERNELDUMPVERSION) {
logmsg(LOG_ERR,
"unknown version (%d) in last dump header on %s",
dtoh32(kdhl.version), device);
status = STATUS_BAD;
if (!force)
goto closefd;
}
}
nfound++;
if (clear)
goto nuke;
if (kerneldump_parity(&kdhl)) {
logmsg(LOG_ERR,
"parity error on last dump header on %s", device);
nerr++;
status = STATUS_BAD;
if (!force)
goto closefd;
}
dumpextent = dtoh64(kdhl.dumpextent);
dumplength = dtoh64(kdhl.dumplength);
dumpkeysize = dtoh32(kdhl.dumpkeysize);
firsthd = lasthd - dumpextent - sectorsize - dumpkeysize;
if (lseek(fddev, firsthd, SEEK_SET) != firsthd ||
read(fddev, temp, sectorsize) != (ssize_t)sectorsize) {
logmsg(LOG_ERR,
"error reading first dump header at offset %lld in %s: %m",
(long long)firsthd, device);
nerr++;
goto closefd;
}
memcpy(&kdhf, temp, sizeof(kdhf));
if (verbose >= 2) {
printf("First dump headers:\n");
printheader(xostdout, &kdhf, device, bounds, -1);
printf("\nLast dump headers:\n");
printheader(xostdout, &kdhl, device, bounds, -1);
printf("\n");
}
if (memcmp(&kdhl, &kdhf, sizeof(kdhl))) {
logmsg(LOG_ERR,
"first and last dump headers disagree on %s", device);
nerr++;
status = STATUS_BAD;
if (!force)
goto closefd;
} else {
status = STATUS_GOOD;
}
if (checkfor) {
printf("A dump exists on %s\n", device);
close(fddev);
exit(0);
}
if (kdhl.panicstring[0] != '\0')
logmsg(LOG_ALERT, "reboot after panic: %.*s",
(int)sizeof(kdhl.panicstring), kdhl.panicstring);
else
logmsg(LOG_ALERT, "reboot");
if (verbose)
printf("Checking for available free space\n");
if (!check_space(savedir, savedirfd, dumplength, bounds)) {
nerr++;
goto closefd;
}
writebounds(savedirfd, bounds + 1);
saved_dump_remove(savedirfd, bounds);
snprintf(infoname, sizeof(infoname), "info.%d", bounds);
/*
* Create or overwrite any existing dump header files.
*/
if ((info = xfopenat(savedirfd, infoname,
O_WRONLY | O_CREAT | O_TRUNC, "w", 0600)) == NULL) {
logmsg(LOG_ERR, "open(%s): %m", infoname);
nerr++;
goto closefd;
}
isencrypted = (dumpkeysize > 0);
if (compress)
snprintf(corename, sizeof(corename), "%s.%d.gz",
istextdump ? "textdump.tar" :
(isencrypted ? "vmcore_encrypted" : "vmcore"), bounds);
else if (iscompressed && !isencrypted && !uncompress)
snprintf(corename, sizeof(corename), "vmcore.%d.%s", bounds,
(kdhl.compression == KERNELDUMP_COMP_GZIP) ? "gz" : "zst");
else
snprintf(corename, sizeof(corename), "%s.%d",
istextdump ? "textdump.tar" :
(isencrypted ? "vmcore_encrypted" : "vmcore"), bounds);
fdcore = openat(savedirfd, corename, O_WRONLY | O_CREAT | O_TRUNC,
0600);
if (fdcore < 0) {
logmsg(LOG_ERR, "open(%s): %m", corename);
fclose(info);
nerr++;
goto closefd;
}
if (compress)
core = zdopen(fdcore, "w");
else
core = fdopen(fdcore, "w");
if (core == NULL) {
logmsg(LOG_ERR, "%s: %m", corename);
(void)close(fdcore);
(void)fclose(info);
nerr++;
goto closefd;
}
fdcore = -1;
xostyle = xo_get_style(NULL);
xoinfo = xo_create_to_file(info, xostyle, 0);
if (xoinfo == NULL) {
logmsg(LOG_ERR, "%s: %m", infoname);
fclose(info);
nerr++;
goto closeall;
}
xo_open_container_h(xoinfo, "crashdump");
if (verbose)
printheader(xostdout, &kdhl, device, bounds, status);
printheader(xoinfo, &kdhl, device, bounds, status);
xo_close_container_h(xoinfo, "crashdump");
xo_flush_h(xoinfo);
xo_finish_h(xoinfo);
fclose(info);
if (isencrypted) {
dumpkey = calloc(1, dumpkeysize);
if (dumpkey == NULL) {
logmsg(LOG_ERR, "Unable to allocate kernel dump key.");
nerr++;
goto closeall;
}
if (read(fddev, dumpkey, dumpkeysize) != (ssize_t)dumpkeysize) {
logmsg(LOG_ERR, "Unable to read kernel dump key: %m.");
nerr++;
goto closeall;
}
snprintf(keyname, sizeof(keyname), "key.%d", bounds);
ret = writekey(savedirfd, keyname, dumpkey, dumpkeysize);
explicit_bzero(dumpkey, dumpkeysize);
if (!ret) {
nerr++;
goto closeall;
}
}
logmsg(LOG_NOTICE, "writing %s%score to %s/%s",
isencrypted ? "encrypted " : "", compress ? "compressed " : "",
savedir, corename);
if (istextdump) {
if (DoTextdumpFile(fddev, dumplength, lasthd, buf, device,
corename, core) < 0)
goto closeall;
} else {
if (DoRegularFile(fddev, dumplength, sectorsize,
!(compress || iscompressed || isencrypted),
uncompress ? kdhl.compression : KERNELDUMP_COMP_NONE,
buf, device, corename, core) < 0) {
goto closeall;
}
}
if (verbose)
printf("\n");
if (fclose(core) < 0) {
logmsg(LOG_ERR, "error on %s: %m", corename);
nerr++;
goto closefd;
}
symlinks_remove(savedirfd);
if (symlinkat(infoname, savedirfd, "info.last") == -1) {
logmsg(LOG_WARNING, "unable to create symlink %s/%s: %m",
savedir, "info.last");
}
if (isencrypted) {
if (symlinkat(keyname, savedirfd, "key.last") == -1) {
logmsg(LOG_WARNING,
"unable to create symlink %s/%s: %m", savedir,
"key.last");
}
}
if ((iscompressed && !uncompress) || compress) {
snprintf(linkname, sizeof(linkname), "%s.last.%s",
istextdump ? "textdump.tar" :
(isencrypted ? "vmcore_encrypted" : "vmcore"),
(kdhl.compression == KERNELDUMP_COMP_ZSTD) ? "zst" : "gz");
} else {
snprintf(linkname, sizeof(linkname), "%s.last",
istextdump ? "textdump.tar" :
(isencrypted ? "vmcore_encrypted" : "vmcore"));
}
if (symlinkat(corename, savedirfd, linkname) == -1) {
logmsg(LOG_WARNING, "unable to create symlink %s/%s: %m",
savedir, linkname);
}
nsaved++;
if (verbose)
printf("dump saved\n");
nuke:
if (!keep) {
if (verbose)
printf("clearing dump header\n");
memcpy(kdhl.magic, KERNELDUMPMAGIC_CLEARED, sizeof(kdhl.magic));
memcpy(temp, &kdhl, sizeof(kdhl));
if (lseek(fddev, lasthd, SEEK_SET) != lasthd ||
write(fddev, temp, sectorsize) != (ssize_t)sectorsize)
logmsg(LOG_ERR,
"error while clearing the dump header: %m");
}
xo_close_container_h(xostdout, "crashdump");
xo_finish_h(xostdout);
free(dumpkey);
free(temp);
close(fddev);
return;
closeall:
fclose(core);
closefd:
free(dumpkey);
free(temp);
close(fddev);
}
/* Prepend "/dev/" to any arguments that don't already have it */
static char **
devify(int argc, char **argv)
{
char **devs;
int i, l;
devs = malloc(argc * sizeof(*argv));
if (devs == NULL) {
logmsg(LOG_ERR, "malloc(): %m");
exit(1);
}
for (i = 0; i < argc; i++) {
if (strncmp(argv[i], _PATH_DEV, sizeof(_PATH_DEV) - 1) == 0)
devs[i] = strdup(argv[i]);
else {
char *fullpath;
fullpath = malloc(PATH_MAX);
if (fullpath == NULL) {
logmsg(LOG_ERR, "malloc(): %m");
exit(1);
}
l = snprintf(fullpath, PATH_MAX, "%s%s", _PATH_DEV,
argv[i]);
if (l < 0) {
logmsg(LOG_ERR, "snprintf(): %m");
exit(1);
} else if (l >= PATH_MAX) {
logmsg(LOG_ERR, "device name too long");
exit(1);
}
devs[i] = fullpath;
}
}
return (devs);
}
static char **
enum_dumpdevs(int *argcp)
{
struct fstab *fsp;
char **argv;
int argc, n;
/*
* We cannot use getfsent(3) in capability mode, so we must
* scan /etc/fstab and build up a list of candidate devices
* before proceeding.
*/
argc = 0;
n = 8;
argv = malloc(n * sizeof(*argv));
if (argv == NULL) {
logmsg(LOG_ERR, "malloc(): %m");
exit(1);
}
for (;;) {
fsp = getfsent();
if (fsp == NULL)
break;
if (strcmp(fsp->fs_vfstype, "swap") != 0 &&
strcmp(fsp->fs_vfstype, "dump") != 0)
continue;
if (argc >= n) {
n *= 2;
argv = realloc(argv, n * sizeof(*argv));
if (argv == NULL) {
logmsg(LOG_ERR, "realloc(): %m");
exit(1);
}
}
argv[argc] = strdup(fsp->fs_spec);
if (argv[argc] == NULL) {
logmsg(LOG_ERR, "strdup(): %m");
exit(1);
}
argc++;
}
*argcp = argc;
return (argv);
}
static void
init_caps(int argc, char **argv)
{
cap_rights_t rights;
cap_channel_t *capcas;
capcas = cap_init();
if (capcas == NULL) {
logmsg(LOG_ERR, "cap_init(): %m");
exit(1);
}
/*
* The fileargs capability does not currently provide a way to limit
* ioctls.
*/
(void)cap_rights_init(&rights, CAP_PREAD, CAP_WRITE, CAP_IOCTL);
capfa = fileargs_init(argc, argv, checkfor || keep ? O_RDONLY : O_RDWR,
0, &rights, FA_OPEN);
if (capfa == NULL) {
logmsg(LOG_ERR, "fileargs_init(): %m");
exit(1);
}
caph_cache_catpages();
caph_cache_tzdata();
if (caph_enter_casper() != 0) {
logmsg(LOG_ERR, "caph_enter_casper(): %m");
exit(1);
}
capsyslog = cap_service_open(capcas, "system.syslog");
if (capsyslog == NULL) {
logmsg(LOG_ERR, "cap_service_open(system.syslog): %m");
exit(1);
}
cap_close(capcas);
}
static void
usage(void)
{
xo_error("%s\n%s\n%s\n",
"usage: savecore -c [-v] [device ...]",
" savecore -C [-v] [device ...]",
" savecore [-fkvz] [-m maxdumps] [directory [device ...]]");
exit(1);
}
int
main(int argc, char **argv)
{
cap_rights_t rights;
const char *savedir;
char **devs;
int i, ch, error, savedirfd;
checkfor = compress = clear = force = keep = false;
verbose = 0;
nfound = nsaved = nerr = 0;
savedir = ".";
openlog("savecore", LOG_PERROR, LOG_DAEMON);
signal(SIGINFO, infohandler);
argc = xo_parse_args(argc, argv);
if (argc < 0)
exit(1);
while ((ch = getopt(argc, argv, "Ccfkm:uvz")) != -1)
switch(ch) {
case 'C':
checkfor = true;
break;
case 'c':
clear = true;
break;
case 'f':
force = true;
break;
case 'k':
keep = true;
break;
case 'm':
maxdumps = atoi(optarg);
if (maxdumps <= 0) {
logmsg(LOG_ERR, "Invalid maxdump value");
exit(1);
}
break;
case 'u':
uncompress = true;
break;
case 'v':
verbose++;
break;
case 'z':
compress = true;
break;
case '?':
default:
usage();
}
if (checkfor && (clear || force || keep))
usage();
if (clear && (compress || keep))
usage();
if (maxdumps > 0 && (checkfor || clear))
usage();
if (compress && uncompress)
usage();
argc -= optind;
argv += optind;
if (argc >= 1 && !checkfor && !clear) {
error = chdir(argv[0]);
if (error) {
logmsg(LOG_ERR, "chdir(%s): %m", argv[0]);
exit(1);
}
savedir = argv[0];
argc--;
argv++;
}
if (argc == 0)
devs = enum_dumpdevs(&argc);
else
devs = devify(argc, argv);
savedirfd = open(savedir, O_RDONLY | O_DIRECTORY);
if (savedirfd < 0) {
logmsg(LOG_ERR, "open(%s): %m", savedir);
exit(1);
}
(void)cap_rights_init(&rights, CAP_CREATE, CAP_FCNTL, CAP_FSTATAT,
CAP_FSTATFS, CAP_PREAD, CAP_SYMLINKAT, CAP_FTRUNCATE, CAP_UNLINKAT,
CAP_WRITE);
if (caph_rights_limit(savedirfd, &rights) < 0) {
logmsg(LOG_ERR, "cap_rights_limit(): %m");
exit(1);
}
/* Enter capability mode. */
init_caps(argc, devs);
for (i = 0; i < argc; i++)
DoFile(savedir, savedirfd, devs[i]);
/* Emit minimal output. */
if (nfound == 0) {
if (checkfor) {
if (verbose)
printf("No dump exists\n");
exit(1);
}
if (verbose)
logmsg(LOG_WARNING, "no dumps found");
} else if (nsaved == 0) {
if (nerr != 0) {
if (verbose)
logmsg(LOG_WARNING,
"unsaved dumps found but not saved");
exit(1);
} else if (verbose)
logmsg(LOG_WARNING, "no unsaved dumps found");
}
return (0);
}
static void
infohandler(int sig __unused)
{
got_siginfo = 1;
}