diff --git a/sbin/savecore/Makefile b/sbin/savecore/Makefile index 172df7e857bc..bcc59a01b795 100644 --- a/sbin/savecore/Makefile +++ b/sbin/savecore/Makefile @@ -1,21 +1,23 @@ # $FreeBSD$ PACKAGE=runtime CONFS= minfree VAR_CRASH= /var/crash VAR_CRASH_MODE= 0750 CONFSDIR= VAR_CRASH PROG= savecore -LIBADD= xo z +LIBADD= xo z zstd MAN= savecore.8 +CFLAGS+= -I${SRCTOP}/sys/contrib/zstd/lib + .include .if ${MK_DYNAMICROOT} == "no" .warning ${PROG} built without libcasper support .elif ${MK_CASPER} != "no" && !defined(RESCUE) CFLAGS+= -DWITH_CASPER LIBADD+= casper cap_fileargs cap_syslog .endif .include diff --git a/sbin/savecore/savecore.8 b/sbin/savecore/savecore.8 index e7b0414b62dc..512da5cc3dae 100644 --- a/sbin/savecore/savecore.8 +++ b/sbin/savecore/savecore.8 @@ -1,190 +1,192 @@ .\" Copyright (c) 1980, 1991, 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. .\" .\" From: @(#)savecore.8 8.1 (Berkeley) 6/5/93 .\" $FreeBSD$ .\" -.Dd March 17, 2018 +.Dd November 17, 2020 .Dt SAVECORE 8 .Os .Sh NAME .Nm savecore .Nd "save a core dump of the operating system" .Sh SYNOPSIS .Nm .Fl c .Op Fl v .Op Ar device ... .Nm .Fl C .Op Fl v .Op Ar device ... .Nm .Op Fl -libxo -.Op Fl fkvz +.Op Fl fkuvz .Op Fl m Ar maxdumps .Op Ar directory Op Ar device ... .Sh DESCRIPTION The .Nm utility copies a core dump into .Ar directory , or the current working directory if no .Ar directory argument is given, and enters a reboot message and information about the core dump into the system log. .Pp The options are as follows: .Bl -tag -width ".Fl m Ar maxdumps" .It Fl -libxo Generate output via .Xr libxo 3 in a selection of different human and machine readable formats. See .Xr xo_parse_args 3 for details on command line arguments. .It Fl C Check to see if a dump exists, and display a brief message to indicate the status. An exit status of 0 indicates that a dump is there, 1 indicates that none exists. This option is compatible only with the .Op Fl v option. .It Fl c Clear the dump, so that future invocations of .Nm will ignore it. .It Fl f Force a dump to be taken even if either the dump was cleared or if the dump header information is inconsistent. .It Fl k Do not clear the dump after saving it. .It Fl m Ar maxdumps Maximum number of dumps to store. Once the number of stored dumps is equal to .Ar maxdumps the counter will restart from .Dv 0 . +.It Fl u +Uncompress the dump in case it was compressed by the kernel. .It Fl v Print out some additional debugging information. Specify twice for more information. .It Fl z Compress the dump (see .Xr gzip 1 ) . The dump may already be compressed if the kernel was configured to do so by .Xr dumpon 8 . In this case, the option has no effect. .El .Pp The .Nm utility looks for dumps on each device specified by the .Ar device argument(s), or on each device in .Pa /etc/fstab marked as .Dq dump or .Dq swap . The .Nm utility checks the core dump in various ways to make sure that it is complete. If it passes these checks, it saves the core image in .Ar directory Ns Pa /vmcore.# and information about the core in .Ar directory Ns Pa /info.# . If the core is encrypted, it saves the dump key in .Ar directory Ns Pa /key.# . The core can be later decrypted using .Xr decryptcore 8 . For kernel textdumps generated with the .Xr textdump 4 facility, output will be stored in the .Xr tar 5 format and named .Ar directory Ns Pa /textdump.tar.# . The .Dq # is the number from the first line of the file .Ar directory Ns Pa /bounds , and it is incremented and stored back into the file each time .Nm successfully runs. .Pp The .Nm utility also checks the available disk space before attempting to make the copies. If there is insufficient disk space in the file system containing .Ar directory , or if the file .Ar directory Ns Pa /minfree exists and the number of free kilobytes (for non-superusers) in the file system after the copies were made would be less than the number in the first line of this file, the copies are not attempted. .Pp If .Nm successfully copies the kernel and the core dump, the core dump is cleared so that future invocations of .Nm will ignore it. .Pp The .Nm utility is meant to be called near the end of the initialization file .Pa /etc/rc (see .Xr rc 8 ) . .Sh SEE ALSO .Xr gzip 1 , .Xr getbootfile 3 , .Xr libxo 3 , .Xr xo_parse_args 3 , .Xr textdump 4 , .Xr tar 5 , .Xr crashinfo 8 , .Xr decryptcore 8 , .Xr dumpon 8 , .Xr syslogd 8 .Sh HISTORY The .Nm utility appeared in .Bx 4.1 . .Pp Support for kernel textdumps appeared in .Fx 7.1 . .Sh BUGS The minfree code does not consider the effect of compression or sparse files. diff --git a/sbin/savecore/savecore.c b/sbin/savecore/savecore.c index 5ae6cbdaf98a..2406c6d9c617 100644 --- a/sbin/savecore/savecore.c +++ b/sbin/savecore/savecore.c @@ -1,1225 +1,1338 @@ /*- * 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 __FBSDID("$FreeBSD$"); #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include +#define Z_SOLO +#include +#include #include #include #include #include /* 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, clear, force, keep; /* flags */ +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 size_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; + 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); + } + nw += sparsefwrite(zbuf, zbufsize - z->avail_out, fp); + } while (z->avail_in > 0 && rv != Z_STREAM_END); + + return (nw); +} + +static size_t +ZstdWrite(ZSTD_DCtx *Zctx, char *in, size_t insize, FILE *fp) +{ + ZSTD_inBuffer Zin; + ZSTD_outBuffer Zout; + size_t nw = 0; + 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); + } + nw += sparsefwrite(zbuf, Zout.pos, fp); + } while (Zin.pos < Zin.size && rv != 0); + + return (nw); +} + static int -DoRegularFile(int fd, off_t dumpsize, u_int sectorsize, bool sparse, char *buf, - const char *device, const char *filename, FILE *fp) +DoRegularFile(int fd, off_t dumpsize, u_int sectorsize, bool sparse, + uint8_t compression, char *buf, const char *device, + const char *filename, FILE *fp) { - int he, hs, nr, nw, wl; + size_t nr, nw, wl; off_t dmpcnt, origsize; + z_stream z; /* gzip */ + ZSTD_DCtx *Zctx; /* zstd */ dmpcnt = 0; origsize = dumpsize; - he = 0; + 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 > dumpsize) + if (wl > (size_t)dumpsize) wl = dumpsize; nr = read(fd, buf, roundup(wl, sectorsize)); - if (nr != (int)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 (!sparse) { + 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 { - 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) { + else + nw = sparsefwrite(buf, wl, fp); + if ((compression == KERNELDUMP_COMP_NONE && nw != wl) || + (compression != KERNELDUMP_COMP_NONE && nw < 0)) { 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, §orsize); 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) + 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), buf, device, - corename, core) < 0) { + !(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 (compress || iscompressed) { + 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:vz")) != -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; }