123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247 |
- /*-
- * SPDX-License-Identifier: BSD-2-Clause
- *
- * Copyright (c) 2008 Robert N. M. Watson
- * 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.
- *
- * 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.
- */
- #include <sys/types.h>
- #include <sys/sysctl.h>
- #include <err.h>
- #include <errno.h>
- #include <fcntl.h>
- #include <kvm.h>
- #include <limits.h>
- #include <stdio.h>
- #include <stdlib.h>
- #include <string.h>
- #include <sysexits.h>
- #include <unistd.h>
- #include "ddb.h"
- /*
- * Interface with the ddb(4) capture buffer of a live kernel using sysctl, or
- * for a crash dump using libkvm.
- */
- #define SYSCTL_DDB_CAPTURE_BUFOFF "debug.ddb.capture.bufoff"
- #define SYSCTL_DDB_CAPTURE_BUFSIZE "debug.ddb.capture.bufsize"
- #define SYSCTL_DDB_CAPTURE_MAXBUFSIZE "debug.ddb.capture.maxbufsize"
- #define SYSCTL_DDB_CAPTURE_DATA "debug.ddb.capture.data"
- #define SYSCTL_DDB_CAPTURE_INPROGRESS "debug.ddb.capture.inprogress"
- static struct nlist namelist[] = {
- #define X_DB_CAPTURE_BUF 0
- { .n_name = "_db_capture_buf" },
- #define X_DB_CAPTURE_BUFSIZE 1
- { .n_name = "_db_capture_bufsize" },
- #define X_DB_CAPTURE_MAXBUFSIZE 2
- { .n_name = "_db_capture_maxbufsize" },
- #define X_DB_CAPTURE_BUFOFF 3
- { .n_name = "_db_capture_bufoff" },
- #define X_DB_CAPTURE_INPROGRESS 4
- { .n_name = "_db_capture_inprogress" },
- { .n_name = "" },
- };
- static int
- kread(kvm_t *kvm, void *kvm_pointer, void *address, size_t size,
- size_t offset)
- {
- ssize_t ret;
- ret = kvm_read(kvm, (unsigned long)kvm_pointer + offset, address,
- size);
- if (ret < 0 || (size_t)ret != size)
- return (-1);
- return (0);
- }
- static int
- kread_symbol(kvm_t *kvm, int read_index, void *address, size_t size,
- size_t offset)
- {
- ssize_t ret;
- ret = kvm_read(kvm, namelist[read_index].n_value + offset, address, size);
- if (ret < 0 || (size_t)ret != size)
- return (-1);
- return (0);
- }
- static void
- ddb_capture_print_kvm(kvm_t *kvm)
- {
- u_int db_capture_bufoff;
- char *buffer, *db_capture_buf;
- if (kread_symbol(kvm, X_DB_CAPTURE_BUF, &db_capture_buf,
- sizeof(db_capture_buf), 0) < 0)
- errx(-1, "kvm: unable to read db_capture_buf");
- if (kread_symbol(kvm, X_DB_CAPTURE_BUFOFF, &db_capture_bufoff,
- sizeof(db_capture_bufoff), 0) < 0)
- errx(-1, "kvm: unable to read db_capture_bufoff");
- buffer = malloc(db_capture_bufoff + 1);
- if (buffer == NULL)
- err(-1, "malloc: db_capture_bufoff (%u)",
- db_capture_bufoff);
- bzero(buffer, db_capture_bufoff + 1);
- if (kread(kvm, db_capture_buf, buffer, db_capture_bufoff, 0) < 0)
- errx(-1, "kvm: unable to read buffer");
- printf("%s\n", buffer);
- free(buffer);
- }
- static void
- ddb_capture_print_sysctl(void)
- {
- size_t buflen, len;
- char *buffer;
- int ret;
- repeat:
- if (sysctlbyname(SYSCTL_DDB_CAPTURE_DATA, NULL, &buflen, NULL, 0) < 0)
- err(EX_OSERR, "sysctl: %s", SYSCTL_DDB_CAPTURE_DATA);
- if (buflen == 0)
- return;
- buffer = malloc(buflen);
- if (buffer == NULL)
- err(EX_OSERR, "malloc");
- bzero(buffer, buflen);
- len = buflen;
- ret = sysctlbyname(SYSCTL_DDB_CAPTURE_DATA, buffer, &len, NULL, 0);
- if (ret < 0 && errno != ENOMEM)
- err(EX_OSERR, "sysctl: %s", SYSCTL_DDB_CAPTURE_DATA);
- if (ret < 0) {
- free(buffer);
- goto repeat;
- }
- printf("%s\n", buffer);
- free(buffer);
- }
- static void
- ddb_capture_status_kvm(kvm_t *kvm)
- {
- u_int db_capture_bufoff, db_capture_bufsize, db_capture_inprogress;
- if (kread_symbol(kvm, X_DB_CAPTURE_BUFOFF, &db_capture_bufoff,
- sizeof(db_capture_bufoff), 0) < 0)
- errx(-1, "kvm: unable to read db_capture_bufoff");
- if (kread_symbol(kvm, X_DB_CAPTURE_BUFSIZE, &db_capture_bufsize,
- sizeof(db_capture_bufsize), 0) < 0)
- errx(-1, "kvm: unable to read db_capture_bufsize");
- if (kread_symbol(kvm, X_DB_CAPTURE_INPROGRESS,
- &db_capture_inprogress, sizeof(db_capture_inprogress), 0) < 0)
- err(-1, "kvm: unable to read db_capture_inprogress");
- printf("%u/%u bytes used\n", db_capture_bufoff, db_capture_bufsize);
- if (db_capture_inprogress)
- printf("capture is on\n");
- else
- printf("capture is off\n");
- }
- static void
- ddb_capture_status_sysctl(void)
- {
- u_int db_capture_bufoff, db_capture_bufsize, db_capture_inprogress;
- size_t len;
- len = sizeof(db_capture_bufoff);
- if (sysctlbyname(SYSCTL_DDB_CAPTURE_BUFOFF, &db_capture_bufoff, &len,
- NULL, 0) < 0)
- err(EX_OSERR, "sysctl: %s", SYSCTL_DDB_CAPTURE_BUFOFF);
- len = sizeof(db_capture_bufoff);
- if (sysctlbyname(SYSCTL_DDB_CAPTURE_BUFSIZE, &db_capture_bufsize,
- &len, NULL, 0) < 0)
- err(EX_OSERR, "sysctl: %s", SYSCTL_DDB_CAPTURE_BUFSIZE);
- len = sizeof(db_capture_inprogress);
- if (sysctlbyname(SYSCTL_DDB_CAPTURE_INPROGRESS,
- &db_capture_inprogress, &len, NULL, 0) < 0)
- err(EX_OSERR, "sysctl: %s", SYSCTL_DDB_CAPTURE_INPROGRESS);
- printf("%u/%u bytes used\n", db_capture_bufoff, db_capture_bufsize);
- if (db_capture_inprogress)
- printf("capture is on\n");
- else
- printf("capture is off\n");
- }
- void
- ddb_capture(int argc, char *argv[])
- {
- char *mflag, *nflag, errbuf[_POSIX2_LINE_MAX];
- kvm_t *kvm;
- int ch;
- mflag = NULL;
- nflag = NULL;
- kvm = NULL;
- while ((ch = getopt(argc, argv, "M:N:")) != -1) {
- switch (ch) {
- case 'M':
- mflag = optarg;
- break;
- case 'N':
- nflag = optarg;
- break;
- default:
- usage();
- }
- }
- argc -= optind;
- argv += optind;
- if (argc != 1)
- usage();
- if (mflag != NULL) {
- kvm = kvm_openfiles(nflag, mflag, NULL, O_RDONLY, errbuf);
- if (kvm == NULL)
- errx(-1, "ddb_capture: kvm_openfiles: %s", errbuf);
- if (kvm_nlist(kvm, namelist) != 0)
- errx(-1, "ddb_capture: kvm_nlist");
- } else if (nflag != NULL)
- usage();
- if (strcmp(argv[0], "print") == 0) {
- if (kvm != NULL)
- ddb_capture_print_kvm(kvm);
- else
- ddb_capture_print_sysctl();
- } else if (strcmp(argv[0], "status") == 0) {
- if (kvm != NULL)
- ddb_capture_status_kvm(kvm);
- else
- ddb_capture_status_sysctl();
- } else
- usage();
- }
|