/* $NetBSD: savecore.c,v 1.69 2006/10/16 02:56:56 christos Exp $ */ /*- * 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 #ifndef lint __COPYRIGHT("@(#) Copyright (c) 1986, 1992, 1993\n\ The Regents of the University of California. All rights reserved.\n"); #endif /* not lint */ #ifndef lint #if 0 static char sccsid[] = "@(#)savecore.c 8.5 (Berkeley) 4/28/95"; #else __RCSID("$NetBSD: savecore.c,v 1.69 2006/10/16 02:56:56 christos Exp $"); #endif #endif /* not lint */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include extern FILE *zopen(const char *fname, const char *mode); #define KREAD(kd, addr, p)\ (kvm_read(kd, addr, (char *)(p), sizeof(*(p))) != sizeof(*(p))) struct nlist current_nl[] = { /* Namelist for currently running system. */ #define X_DUMPDEV 0 { .n_name = "_dumpdev" }, #define X_DUMPLO 1 { .n_name = "_dumplo" }, #define X_TIME_SECOND 2 { .n_name = "_time_second" }, #define X_TIME 3 { .n_name = "_time" }, #define X_DUMPSIZE 4 { .n_name = "_dumpsize" }, #define X_VERSION 5 { .n_name = "_version" }, #define X_DUMPMAG 6 { .n_name = "_dumpmag" }, #define X_PANICSTR 7 { .n_name = "_panicstr" }, #define X_PANICSTART 8 { .n_name = "_panicstart" }, #define X_PANICEND 9 { .n_name = "_panicend" }, #define X_MSGBUF 10 { .n_name = "_msgbufp" }, { .n_name = NULL }, }; int cursyms[] = { X_DUMPDEV, X_DUMPLO, X_VERSION, X_DUMPMAG, -1 }; int dumpsyms[] = { X_TIME_SECOND, X_TIME, X_DUMPSIZE, X_VERSION, X_PANICSTR, X_DUMPMAG, -1 }; struct nlist dump_nl[] = { /* Name list for dumped system. */ { .n_name = "_dumpdev" }, /* Entries MUST be the same as */ { .n_name = "_dumplo" }, /* those in current_nl[]. */ { .n_name = "_time_second" }, { .n_name = "_time" }, { .n_name = "_dumpsize" }, { .n_name = "_version" }, { .n_name = "_dumpmag" }, { .n_name = "_panicstr" }, { .n_name = "_panicstart" }, { .n_name = "_panicend" }, { .n_name = "_msgbufp" }, { .n_name = NULL }, }; /* Types match kernel declarations. */ off_t dumplo; /* where dump starts on dumpdev */ u_int32_t dumpmag; /* magic number in dump */ int dumpsize; /* amount of memory dumped */ off_t dumpbytes; /* in bytes */ const char *kernel; /* name of used kernel */ char *dirname; /* directory to save dumps in */ char *ddname; /* name of dump device */ dev_t dumpdev; /* dump device */ int dumpfd; /* read/write descriptor on block dev */ kvm_t *kd_dump; /* kvm descriptor on block dev */ time_t now; /* current date */ char panic_mesg[1024]; long panicstr; char vers[1024]; char gzmode[3]; static int clear, compress, force, verbose; /* flags */ void check_kmem(void); int check_space(void); void clear_dump(void); int Create(char *, int); int dump_exists(void); char *find_dev(dev_t, int); int get_crashtime(void); void kmem_setup(void); void Lseek(int, off_t, int); int main(int, char *[]); int Open(const char *, int rw); char *rawname(char *s); void save_core(void); void usage(void); void Write(int, void *, int); int main(int argc, char *argv[]) { int ch, level, testonly; char *ep; dirname = NULL; kernel = NULL; level = 1; /* default to fastest gzip compression */ testonly = 0; gzmode[0] = 'w'; openlog("savecore", LOG_PERROR, LOG_DAEMON); while ((ch = getopt(argc, argv, "cdfnN:vzZ:")) != -1) switch(ch) { case 'c': clear = 1; break; case 'd': /* Not documented. */ case 'v': verbose = 1; break; case 'f': force = 1; break; case 'n': testonly = 1; break; case 'N': kernel = optarg; break; case 'z': compress = 1; break; case 'Z': level = (int)strtol(optarg, &ep, 10); if (level < 0 || level > 9) { (void)syslog(LOG_ERR, "invalid compression %s", optarg); usage(); } break; case '?': default: usage(); } argc -= optind; argv += optind; if (argc != ((clear || testonly) ? 0 : 1)) usage(); gzmode[1] = level + '0'; if (!clear) dirname = argv[0]; if (kernel == NULL) { kernel = getbootfile(); } (void)time(&now); kmem_setup(); if (clear && !testonly) { clear_dump(); exit(0); } if (!dump_exists() && !force) exit(1); if (testonly) /* If -n was passed and there was a dump, exit at level 0 */ exit(0); check_kmem(); if (panicstr) syslog(LOG_ALERT, "reboot after panic: %s", panic_mesg); else syslog(LOG_ALERT, "reboot"); if ((!get_crashtime() || !check_space()) && !force) exit(1); save_core(); clear_dump(); exit(0); } void kmem_setup(void) { kvm_t *kd_kern; char errbuf[_POSIX2_LINE_MAX]; int i, hdrsz; /* * Some names we need for the currently running system, others for * the system that was running when the dump was made. The values * obtained from the current system are used to look for things in * /dev/kmem that cannot be found in the kernel namelist, but are * presumed to be the same (since the disk partitions are probably * the same!) */ kd_kern = kvm_openfiles(kernel, NULL, NULL, O_RDONLY, errbuf); if (kd_kern == NULL) { syslog(LOG_ERR, "%s: kvm_openfiles: %s", kernel, errbuf); exit(1); } if (kvm_nlist(kd_kern, current_nl) == -1) syslog(LOG_ERR, "%s: kvm_nlist: %s", kernel, kvm_geterr(kd_kern)); for (i = 0; cursyms[i] != -1; i++) if (current_nl[cursyms[i]].n_value == 0 && cursyms[i] != X_TIME_SECOND && cursyms[i] != X_TIME) { syslog(LOG_ERR, "%s: %s not in namelist", kernel, current_nl[cursyms[i]].n_name); exit(1); } if (KREAD(kd_kern, current_nl[X_DUMPDEV].n_value, &dumpdev) != 0) { if (verbose) syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_kern)); exit(1); } if (dumpdev == NODEV) { syslog(LOG_WARNING, "no core dump (no dumpdev)"); exit(1); } { long l_dumplo; if (KREAD(kd_kern, current_nl[X_DUMPLO].n_value, &l_dumplo) != 0) { if (verbose) syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_kern)); exit(1); } if (l_dumplo == -1) { syslog(LOG_WARNING, "no core dump (invalid dumplo)"); exit(1); } dumplo = DEV_BSIZE * (off_t) l_dumplo; } if (verbose) (void)printf("dumplo = %lld (%ld * %ld)\n", (long long)dumplo, (long)(dumplo / DEV_BSIZE), (long)DEV_BSIZE); if (KREAD(kd_kern, current_nl[X_DUMPMAG].n_value, &dumpmag) != 0) { if (verbose) syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_kern)); exit(1); } (void)kvm_read(kd_kern, current_nl[X_VERSION].n_value, vers, sizeof(vers)); vers[sizeof(vers) - 1] = '\0'; ddname = find_dev(dumpdev, S_IFBLK); dumpfd = Open(ddname, O_RDWR); kd_dump = kvm_openfiles(kernel, ddname, NULL, O_RDWR, errbuf); if (kd_dump == NULL) { syslog(LOG_ERR, "%s: kvm_openfiles: %s", kernel, errbuf); exit(1); } if (kvm_nlist(kd_dump, dump_nl) == -1) syslog(LOG_ERR, "%s: kvm_nlist: %s", kernel, kvm_geterr(kd_dump)); for (i = 0; dumpsyms[i] != -1; i++) if (dump_nl[dumpsyms[i]].n_value == 0 && dumpsyms[i] != X_TIME_SECOND && dumpsyms[i] != X_TIME) { syslog(LOG_ERR, "%s: %s not in namelist", kernel, dump_nl[dumpsyms[i]].n_name); exit(1); } hdrsz = kvm_dump_mkheader(kd_dump, dumplo); /* * If 'hdrsz' == 0, kvm_dump_mkheader() failed on the magic-number * checks, ergo no dump is present... */ if (hdrsz == 0) { syslog(LOG_WARNING, "no core dump"); exit(1); } if (hdrsz == -1) { syslog(LOG_ERR, "%s: kvm_dump_mkheader: %s", kernel, kvm_geterr(kd_dump)); exit(1); } dumplo += hdrsz; kvm_close(kd_kern); } void check_kmem(void) { char *cp, *bufdata; struct kern_msgbuf msgbuf, *bufp; long panicloc, panicstart, panicend; char core_vers[1024]; (void)kvm_read(kd_dump, dump_nl[X_VERSION].n_value, core_vers, sizeof(core_vers)); core_vers[sizeof(core_vers) - 1] = '\0'; if (strcmp(vers, core_vers) != 0) syslog(LOG_WARNING, "warning: %s version mismatch:\n\t%s\nand\t%s\n", kernel, vers, core_vers); panicstart = panicend = 0; if (KREAD(kd_dump, dump_nl[X_PANICSTART].n_value, &panicstart) != 0) { if (verbose) syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_dump)); goto nomsguf; } if (KREAD(kd_dump, dump_nl[X_PANICEND].n_value, &panicend) != 0) { if (verbose) syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_dump)); goto nomsguf; } if (panicstart != 0 && panicend != 0) { if (KREAD(kd_dump, dump_nl[X_MSGBUF].n_value, &bufp)) { if (verbose) syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_dump)); goto nomsguf; } if (kvm_read(kd_dump, (long)bufp, &msgbuf, offsetof(struct kern_msgbuf, msg_bufc)) != offsetof(struct kern_msgbuf, msg_bufc)) { if (verbose) syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_dump)); goto nomsguf; } if (msgbuf.msg_magic != MSG_MAGIC) { if (verbose) syslog(LOG_WARNING, "msgbuf magic incorrect"); goto nomsguf; } bufdata = malloc(msgbuf.msg_bufs); if (bufdata == NULL) { if (verbose) syslog(LOG_WARNING, "couldn't allocate space for msgbuf data"); goto nomsguf; } if (kvm_read(kd_dump, (long)&bufp->msg_bufc, bufdata, msgbuf.msg_bufs) != msgbuf.msg_bufs) { if (verbose) syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_dump)); free(bufdata); goto nomsguf; } cp = panic_mesg; while (panicstart != panicend && cp < &panic_mesg[sizeof(panic_mesg)-1]) { *cp++ = bufdata[panicstart]; panicstart++; if (panicstart >= msgbuf.msg_bufs) panicstart = 0; } /* Don't end in a new-line */ cp = &panic_mesg[strlen(panic_mesg)] - 1; if (*cp == '\n') *cp = '\0'; panic_mesg[sizeof(panic_mesg) - 1] = '\0'; free(bufdata); panicstr = 1; /* anything not zero */ return; } nomsguf: if (KREAD(kd_dump, dump_nl[X_PANICSTR].n_value, &panicstr) != 0) { if (verbose) syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_dump)); return; } if (panicstr) { cp = panic_mesg; panicloc = panicstr; do { if (KREAD(kd_dump, panicloc, cp) != 0) { if (verbose) syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_dump)); break; } panicloc++; } while (*cp++ && cp < &panic_mesg[sizeof(panic_mesg)-1]); panic_mesg[sizeof(panic_mesg) - 1] = '\0'; } } int dump_exists(void) { u_int32_t newdumpmag; if (KREAD(kd_dump, dump_nl[X_DUMPMAG].n_value, &newdumpmag) != 0) { if (verbose) syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_dump)); return (0); } /* Read the dump size. */ if (KREAD(kd_dump, dump_nl[X_DUMPSIZE].n_value, &dumpsize) != 0) { if (verbose) syslog(LOG_WARNING, "kvm_read: %s", kvm_geterr(kd_dump)); return (0); } dumpbytes = (off_t)dumpsize * getpagesize(); /* * Return zero if core dump doesn't seem to be there, and note * it for syslog. This check and return happens after the dump size * is read, so dumpsize is whether or not the core is valid (for -f). */ if (newdumpmag != dumpmag) { if (verbose) syslog(LOG_WARNING, "magic number mismatch (0x%x != 0x%x)", newdumpmag, dumpmag); syslog(LOG_WARNING, "no core dump"); return (0); } return (1); } void clear_dump(void) { if (kvm_dump_inval(kd_dump) == -1) syslog(LOG_ERR, "%s: kvm_clear_dump: %s", ddname, kvm_geterr(kd_dump)); } char buf[1024 * 1024]; void save_core(void) { FILE *fp; int bounds, ifd, nr, nw, ofd; char *rawp, path[MAXPATHLEN]; ofd = -1; /* * Get the current number and update the bounds file. Do the update * now, because may fail later and don't want to overwrite anything. */ umask(066); (void)snprintf(path, sizeof(path), "%s/bounds", dirname); if ((fp = fopen(path, "r")) == NULL) goto err1; if (fgets(buf, sizeof(buf), fp) == NULL) { if (ferror(fp)) err1: syslog(LOG_WARNING, "%s: %m", path); bounds = 0; } else bounds = atoi(buf); if (fp != NULL) (void)fclose(fp); if ((fp = fopen(path, "w")) == NULL) syslog(LOG_ERR, "%s: %m", path); else { (void)fprintf(fp, "%d\n", bounds + 1); (void)fclose(fp); } /* Create the core file. */ (void)snprintf(path, sizeof(path), "%s/netbsd.%d.core%s", dirname, bounds, compress ? ".gz" : ""); if (compress) { if ((fp = zopen(path, gzmode)) == NULL) { syslog(LOG_ERR, "%s: %m", path); exit(1); } } else { ofd = Create(path, S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH); fp = fdopen(ofd, "w"); if (fp == NULL) { syslog(LOG_ERR, "%s: fdopen: %m", path); exit(1); } } /* Open the raw device. */ rawp = rawname(ddname); if ((ifd = open(rawp, O_RDONLY)) == -1) { syslog(LOG_WARNING, "%s: %m; using block device", rawp); ifd = dumpfd; } /* Seek to the start of the core. */ Lseek(ifd, dumplo, SEEK_SET); if (kvm_dump_wrtheader(kd_dump, fp, (int32_t)dumpbytes) == -1) { syslog(LOG_ERR, "kvm_dump_wrtheader: %s : %s", path, kvm_geterr(kd_dump)); exit(1); } /* Copy the core file. */ syslog(LOG_NOTICE, "writing %score to %s", compress ? "compressed " : "", path); for (; dumpbytes > (off_t)0; dumpbytes -= (off_t)nr) { char nbuf[7]; humanize_number(nbuf, 7, dumpbytes, "", HN_AUTOSCALE, 0); (void)printf("%7s\r", nbuf); (void)fflush(stdout); nr = read(ifd, buf, MIN(dumpbytes, sizeof(buf))); if (nr <= 0) { if (nr == 0) syslog(LOG_WARNING, "WARNING: EOF on dump device"); else syslog(LOG_ERR, "%s: %m", rawp); goto err2; } nw = fwrite(buf, 1, nr, fp); if (nw != nr) { syslog(LOG_ERR, "%s: %s", path, strerror(nw == 0 ? EIO : errno)); err2: syslog(LOG_WARNING, "WARNING: core may be incomplete"); (void)printf("\n"); exit(1); } } (void)close(ifd); (void)fclose(fp); /* Copy the kernel. */ ifd = Open(kernel, O_RDONLY); (void)snprintf(path, sizeof(path), "%s/netbsd.%d%s", dirname, bounds, compress ? ".gz" : ""); if (compress) { if ((fp = zopen(path, gzmode)) == NULL) { syslog(LOG_ERR, "%s: %m", path); exit(1); } } else ofd = Create(path, S_IRUSR | S_IWUSR); syslog(LOG_NOTICE, "writing %skernel to %s", compress ? "compressed " : "", path); while ((nr = read(ifd, buf, sizeof(buf))) > 0) { if (compress) nw = fwrite(buf, 1, nr, fp); else nw = write(ofd, buf, nr); if (nw != nr) { syslog(LOG_ERR, "%s: %s", path, strerror(nw == 0 ? EIO : errno)); syslog(LOG_WARNING, "WARNING: kernel may be incomplete"); exit(1); } } if (nr < 0) { syslog(LOG_ERR, "%s: %m", kernel); syslog(LOG_WARNING, "WARNING: kernel may be incomplete"); exit(1); } if (compress) (void)fclose(fp); else (void)close(ofd); } char * find_dev(dev_t dev, int type) { DIR *dfd; struct dirent *dir; struct stat sb; char *dp, device[MAXPATHLEN + 1], *p; size_t l; if ((dfd = opendir(_PATH_DEV)) == NULL) { syslog(LOG_ERR, "%s: %m", _PATH_DEV); exit(1); } strlcpy(device, _PATH_DEV, sizeof(device)); p = &device[strlen(device)]; l = sizeof(device) - strlen(device); while ((dir = readdir(dfd))) { strlcpy(p, dir->d_name, l); if (lstat(device, &sb)) { syslog(LOG_ERR, "%s: %m", device); continue; } if ((sb.st_mode & S_IFMT) != type) continue; if (dev == sb.st_rdev) { closedir(dfd); if ((dp = strdup(device)) == NULL) { syslog(LOG_ERR, "%m"); exit(1); } return (dp); } } closedir(dfd); syslog(LOG_ERR, "can't find device %d/%d", major(dev), minor(dev)); exit(1); } char * rawname(char *s) { char *sl; char name[MAXPATHLEN]; if ((sl = strrchr(s, '/')) == NULL || sl[1] == '0') { syslog(LOG_ERR, "can't make raw dump device name from %s", s); return (s); } (void)snprintf(name, sizeof(name), "%.*s/r%s", (int)(sl - s), s, sl + 1); if ((sl = strdup(name)) == NULL) { syslog(LOG_ERR, "%m"); exit(1); } return (sl); } int get_crashtime(void) { time_t dumptime; /* Time the dump was taken. */ struct timeval dtime; if (KREAD(kd_dump, dump_nl[X_TIME_SECOND].n_value, &dumptime) != 0) { if (KREAD(kd_dump, dump_nl[X_TIME].n_value, &dtime) != 0) { if (verbose) syslog(LOG_WARNING, "kvm_read: %s (and _time_seconf is not defined also)", kvm_geterr(kd_dump)); return (0); } dumptime = dtime.tv_sec; } if (dumptime == 0) { if (verbose) syslog(LOG_ERR, "dump time is zero"); return (0); } (void)printf("savecore: system went down at %s", ctime(&dumptime)); #define LEEWAY (60 * SECSPERDAY) if (dumptime < now - LEEWAY || dumptime > now + LEEWAY) { (void)printf("dump time is unreasonable\n"); return (0); } return (1); } int check_space(void) { FILE *fp; off_t minfree, spacefree, kernelsize, needed; struct stat st; struct statvfs fsbuf; char mbuf[100], path[MAXPATHLEN]; #ifdef __GNUC__ (void) &minfree; #endif if (stat(kernel, &st) < 0) { syslog(LOG_ERR, "%s: %m", kernel); exit(1); } kernelsize = st.st_blocks * S_BLKSIZE; if (statvfs(dirname, &fsbuf) < 0) { syslog(LOG_ERR, "%s: %m", dirname); exit(1); } spacefree = fsbuf.f_bavail; spacefree *= fsbuf.f_frsize; spacefree /= 1024; (void)snprintf(path, sizeof(path), "%s/minfree", dirname); if ((fp = fopen(path, "r")) == NULL) minfree = 0; else { if (fgets(mbuf, sizeof(mbuf), fp) == NULL) minfree = 0; else minfree = atoi(mbuf); (void)fclose(fp); } needed = (dumpbytes + kernelsize) / 1024; if (minfree > 0 && spacefree - needed < minfree) { syslog(LOG_WARNING, "no dump, not enough free space in %s", dirname); return (0); } if (spacefree - needed < minfree) syslog(LOG_WARNING, "dump performed, but free space threshold crossed"); return (1); } int Open(const char *name, int rw) { int fd; if ((fd = open(name, rw, 0)) < 0) { syslog(LOG_ERR, "%s: %m", name); exit(1); } return (fd); } void Lseek(int fd, off_t off, int flag) { off_t ret; ret = lseek(fd, off, flag); if (ret == -1) { syslog(LOG_ERR, "lseek: %m"); exit(1); } } int Create(char *file, int mode) { int fd; fd = open(file, O_WRONLY | O_CREAT | O_TRUNC, mode); if (fd < 0) { syslog(LOG_ERR, "%s: %m", file); exit(1); } return (fd); } void Write(int fd, void *bp, int size) { int n; if ((n = write(fd, bp, size)) < size) { syslog(LOG_ERR, "write: %s", strerror(n == -1 ? errno : EIO)); exit(1); } } void usage(void) { (void)syslog(LOG_ERR, "usage: savecore [-cfnvz] [-N system] [-Z level] directory"); exit(1); }