/*-
 * 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/param.h>
#include <sys/disk.h>
#include <sys/kerneldump.h>
#include <sys/memrange.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

#define LOG_OPTIONS  LOG_PERROR
#define LOG_FACILITY LOG_DAEMON

static cap_channel_t *capsyslog;
static fileargs_t *capfa;
static bool checkfor, compress, uncompress, clear, force, keep; /* flags */
static bool livecore;   /* flags cont. */
static int verbose;
static int nfound, nsaved, nerr;                        /* statistics */
static int maxdumps;
static uint8_t comp_desired;

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");
        if (maxdumps > 0 && ret == maxdumps)
                ret = 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 int
write_header_info(xo_handle_t *xostdout, const struct kerneldumpheader *kdh,
    int savedirfd, const char *infoname, const char *device, int bounds,
    int status)
{
        xo_handle_t *xoinfo;
        FILE *info;

        /*
         * 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);
                return (-1);
        }

        xoinfo = xo_create_to_file(info, xo_get_style(NULL), 0);
        if (xoinfo == NULL) {
                logmsg(LOG_ERR, "%s: %m", infoname);
                fclose(info);
                return (-1);
        }
        xo_open_container_h(xoinfo, "crashdump");

        if (verbose)
                printheader(xostdout, kdh, device, bounds, status);

        printheader(xoinfo, kdh, device, bounds, status);
        xo_close_container_h(xoinfo, "crashdump");
        xo_flush_h(xoinfo);
        if (xo_finish_h(xoinfo) < 0)
                xo_err(EXIT_FAILURE, "stdout");
        fclose(info);

        return (0);
}

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)
{
        char path[32];
        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)
{
        char path[32];

        (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);
        (void)snprintf(path, sizeof(path), "livecore.%d", bounds);
        (void)unlinkat(savedirfd, path, 0);
        (void)snprintf(path, sizeof(path), "livecore.%d.gz", bounds);
        (void)unlinkat(savedirfd, path, 0);
        (void)snprintf(path, sizeof(path), "livecore.%d.zst", 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);
        (void)unlinkat(savedirfd, "livecore.last", 0);
        (void)unlinkat(savedirfd, "livecore.last.gz", 0);
        (void)unlinkat(savedirfd, "livecore.last.zst", 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(EXIT_FAILURE);
        }
        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
DoLiveFile(const char *savedir, int savedirfd, const char *device)
{
        char infoname[32], corename[32], linkname[32], tmpname[32];
        struct mem_livedump_arg marg;
        struct kerneldumpheader kdhl;
        xo_handle_t *xostdout;
        off_t dumplength;
        uint32_t version;
        int fddev, fdcore;
        int bounds;
        int error, status;

        bounds = getbounds(savedirfd);
        status = STATUS_UNKNOWN;

        xostdout = xo_create_to_file(stdout, XO_STYLE_TEXT, 0);
        if (xostdout == NULL) {
                logmsg(LOG_ERR, "xo_create_to_file() failed: %m");
                return;
        }

        /*
         * Create a temporary file. We will invoke the live dump and its
         * contents will be written to this fd. After validating and removing
         * the kernel dump header from the tail-end of this file, it will be
         * renamed to its definitive filename (e.g. livecore.2.gz).
         *
         * If any errors are encountered before the rename, the temporary file
         * is unlinked.
         */
        strcpy(tmpname, "livecore.tmp.XXXXXX");
        fdcore = mkostempsat(savedirfd, tmpname, 0, 0);
        if (fdcore < 0) {
                logmsg(LOG_ERR, "error opening temp file: %m");
                return;
        }

        fddev = fileargs_open(capfa, device);
        if (fddev < 0) {
                logmsg(LOG_ERR, "%s: %m", device);
                goto unlinkexit;
        }

        bzero(&marg, sizeof(marg));
        marg.fd = fdcore;
        marg.compression = comp_desired;
        if (ioctl(fddev, MEM_KERNELDUMP, &marg) == -1) {
                logmsg(LOG_ERR,
                    "failed to invoke live-dump on system: %m");
                close(fddev);
                goto unlinkexit;
        }

        /* Close /dev/mem fd, we are finished with it. */
        close(fddev);

        /* Seek to the end of the file, minus the size of the header. */
        if (lseek(fdcore, -(off_t)sizeof(kdhl), SEEK_END) == -1) {
                logmsg(LOG_ERR, "failed to lseek: %m");
                goto unlinkexit;
        }

        if (read(fdcore, &kdhl, sizeof(kdhl)) != sizeof(kdhl)) {
                logmsg(LOG_ERR, "failed to read kernel dump header: %m");
                goto unlinkexit;
        }
        /* Reset cursor */
        (void)lseek(fdcore, 0, SEEK_SET);

        /* Validate the dump header. */
        version = dtoh32(kdhl.version);
        if (compare_magic(&kdhl, KERNELDUMPMAGIC)) {
                if (version != KERNELDUMPVERSION) {
                        logmsg(LOG_ERR,
                            "unknown version (%d) in dump header on %s",
                            version, device);
                        goto unlinkexit;
                } else if (kdhl.compression != comp_desired) {
                        /* This should be impossible. */
                        logmsg(LOG_ERR,
                            "dump compression (%u) doesn't match request (%u)",
                            kdhl.compression, comp_desired);
                        if (!force)
                                goto unlinkexit;
                }
        } else {
                logmsg(LOG_ERR, "magic mismatch on live dump header");
                goto unlinkexit;
        }
        if (kerneldump_parity(&kdhl)) {
                logmsg(LOG_ERR,
                    "parity error on last dump header on %s", device);
                nerr++;
                status = STATUS_BAD;
                if (!force)
                        goto unlinkexit;
        } else {
                status = STATUS_GOOD;
        }

        nfound++;
        dumplength = dtoh64(kdhl.dumplength);
        if (dtoh32(kdhl.dumpkeysize) != 0) {
                logmsg(LOG_ERR,
                    "dump header unexpectedly reported keysize > 0");
                goto unlinkexit;
        }

        /* Remove the vestigial kernel dump header. */
        error = ftruncate(fdcore, dumplength);
        if (error != 0) {
                logmsg(LOG_ERR, "failed to truncate the core file: %m");
                goto unlinkexit;
        }

        if (verbose >= 2) {
                printf("\nDump header:\n");
                printheader(xostdout, &kdhl, device, bounds, -1);
                printf("\n");
        }
        logmsg(LOG_ALERT, "livedump");

        writebounds(savedirfd, bounds + 1);
        saved_dump_remove(savedirfd, bounds);

        snprintf(corename, sizeof(corename), "livecore.%d", bounds);
        if (compress)
                strcat(corename, kdhl.compression == KERNELDUMP_COMP_ZSTD ?
                    ".zst" : ".gz");

        if (verbose)
                printf("renaming %s to %s\n", tmpname, corename);
        if (renameat(savedirfd, tmpname, savedirfd, corename) != 0) {
                logmsg(LOG_ERR, "renameat failed: %m");
                goto unlinkexit;
        }

        snprintf(infoname, sizeof(infoname), "info.%d", bounds);
        if (write_header_info(xostdout, &kdhl, savedirfd, infoname, device,
            bounds, status) != 0) {
                nerr++;
                return;
        }

        logmsg(LOG_NOTICE, "writing %score to %s/%s",
            compress ? "compressed " : "", savedir, corename);

        if (verbose)
                printf("\n");

        symlinks_remove(savedirfd);
        if (symlinkat(infoname, savedirfd, "info.last") == -1) {
                logmsg(LOG_WARNING, "unable to create symlink %s/%s: %m",
                    savedir, "info.last");
        }

        snprintf(linkname, sizeof(linkname), "livecore.last");
        if (compress)
                strcat(linkname, kdhl.compression == KERNELDUMP_COMP_ZSTD ?
                    ".zst" : ".gz");
        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");

        close(fdcore);
        return;
unlinkexit:
        funlinkat(savedirfd, tmpname, fdcore, 0);
        close(fdcore);
}

static void
DoFile(const char *savedir, int savedirfd, const char *device)
{
        static char *buf = NULL;
        xo_handle_t *xostdout;
        char infoname[32], corename[32], linkname[32], keyname[32];
        char *temp = NULL;
        struct kerneldumpheader kdhf, kdhl;
        uint8_t *dumpkey;
        off_t mediasize, dumpextent, dumplength, firsthd, lasthd;
        FILE *core;
        int fdcore, fddev, error;
        int bounds, status;
        u_int sectorsize;
        uint32_t dumpkeysize;
        bool iscompressed, isencrypted, istextdump, ret;

        /* Live kernel dumps are handled separately. */
        if (livecore) {
                DoLiveFile(savedir, savedirfd, device);
                return;
        }

        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, "xo_create_to_file() failed: %m");
                return;
        }

        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(EXIT_SUCCESS);
        }

        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);

        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);
                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);
                nerr++;
                goto closefd;
        }
        fdcore = -1;

        snprintf(infoname, sizeof(infoname), "info.%d", bounds);
        if (write_header_info(xostdout, &kdhl, savedirfd, infoname, device,
            bounds, status) != 0) {
                nerr++;
                goto closeall;
        }

        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");
        if (xo_finish_h(xostdout) < 0)
                xo_err(EXIT_FAILURE, "stdout");
        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(EXIT_FAILURE);
        }
        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(EXIT_FAILURE);
                        }
                        l = snprintf(fullpath, PATH_MAX, "%s%s", _PATH_DEV,
                            argv[i]);
                        if (l < 0) {
                                logmsg(LOG_ERR, "snprintf(): %m");
                                exit(EXIT_FAILURE);
                        } else if (l >= PATH_MAX) {
                                logmsg(LOG_ERR, "device name too long");
                                exit(EXIT_FAILURE);
                        }
                        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(EXIT_FAILURE);
        }
        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(EXIT_FAILURE);
                        }
                }
                argv[argc] = strdup(fsp->fs_spec);
                if (argv[argc] == NULL) {
                        logmsg(LOG_ERR, "strdup(): %m");
                        exit(EXIT_FAILURE);
                }
                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(EXIT_FAILURE);
        }
        /*
         * 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(EXIT_FAILURE);
        }
        caph_cache_catpages();
        caph_cache_tzdata();
        if (caph_enter_casper() != 0) {
                logmsg(LOG_ERR, "caph_enter_casper(): %m");
                exit(EXIT_FAILURE);
        }
        capsyslog = cap_service_open(capcas, "system.syslog");
        if (capsyslog == NULL) {
                logmsg(LOG_ERR, "cap_service_open(system.syslog): %m");
                exit(EXIT_FAILURE);
        }
        cap_close(capcas);
        cap_openlog(capsyslog, "savecore", LOG_OPTIONS, LOG_FACILITY);
}

static void
usage(void)
{
        xo_error("%s\n%s\n%s\n%s\n",
            "usage: savecore -c [-v] [device ...]",
            "       savecore -C [-v] [device ...]",
            "       savecore -L [-fvZz] [-m maxdumps] [directory]",
            "       savecore [-fkuvz] [-m maxdumps] [directory [device ...]]");
        exit(EXIT_FAILURE);
}

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 = livecore = false;
        verbose = 0;
        nfound = nsaved = nerr = 0;
        savedir = ".";
        comp_desired = KERNELDUMP_COMP_NONE;

        openlog("savecore", LOG_OPTIONS, LOG_FACILITY);
        signal(SIGINFO, infohandler);

        argc = xo_parse_args(argc, argv);
        if (argc < 0)
                exit(EXIT_FAILURE);

        while ((ch = getopt(argc, argv, "CcfkLm:uvZz")) != -1)
                switch(ch) {
                case 'C':
                        checkfor = true;
                        break;
                case 'c':
                        clear = true;
                        break;
                case 'f':
                        force = true;
                        break;
                case 'k':
                        keep = true;
                        break;
                case 'L':
                        livecore = true;
                        break;
                case 'm':
                        maxdumps = atoi(optarg);
                        if (maxdumps <= 0) {
                                logmsg(LOG_ERR, "Invalid maxdump value");
                                exit(EXIT_FAILURE);
                        }
                        break;
                case 'u':
                        uncompress = true;
                        break;
                case 'v':
                        verbose++;
                        break;
                case 'Z':
                        /* No on-the-fly compression with zstd at the moment. */
                        if (!livecore)
                                usage();
                        compress = true;
                        comp_desired = KERNELDUMP_COMP_ZSTD;
                        break;
                case 'z':
                        compress = true;
                        comp_desired = KERNELDUMP_COMP_GZIP;
                        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();
        if (livecore && (checkfor || clear || uncompress || keep))
                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(EXIT_FAILURE);
                }
                savedir = argv[0];
                argc--;
                argv++;
        }
        if (livecore) {
                if (argc > 0)
                        usage();

                /* Always need /dev/mem to invoke the dump */
                devs = malloc(sizeof(char *));
                devs[0] = strdup("/dev/mem");
                argc++;
        } else 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(EXIT_FAILURE);
        }
        (void)cap_rights_init(&rights, CAP_CREATE, CAP_FCNTL, CAP_FSTATAT,
            CAP_FSTATFS, CAP_PREAD, CAP_SYMLINKAT, CAP_FTRUNCATE, CAP_UNLINKAT,
            CAP_WRITE);
        if (livecore)
                cap_rights_set(&rights, CAP_RENAMEAT_SOURCE,
                    CAP_RENAMEAT_TARGET);
        if (caph_rights_limit(savedirfd, &rights) < 0) {
                logmsg(LOG_ERR, "cap_rights_limit(): %m");
                exit(EXIT_FAILURE);
        }

        /* Enter capability mode. */
        init_caps(argc, devs);

        for (i = 0; i < argc; i++)
                DoFile(savedir, savedirfd, devs[i]);

        if (nfound == 0) {
                if (checkfor) {
                        if (verbose)
                                printf("No dump exists\n");
                        exit(EXIT_FAILURE);
                }
                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(EXIT_FAILURE);
                } else if (verbose)
                        logmsg(LOG_WARNING, "no unsaved dumps found");
        } else if (verbose) {
                logmsg(LOG_NOTICE, "%d cores saved in %s\n", nsaved, savedir);
        }

        exit(EXIT_SUCCESS);
}

static void
infohandler(int sig __unused)
{
        got_siginfo = 1;
}