/*-
* Copyright (c) 2006 The FreeBSD Project
* 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/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/types.h>
#include <sys/param.h>
#include <sys/queue.h> /* for <sys/linker.h> with _KERNEL defined */
#include <err.h>
#include <fcntl.h>
#include <kvm.h>
#include <limits.h>
#include <nlist.h>
#include <stdlib.h>
#include <string.h>
#define _KERNEL
#include <sys/linker.h>
#undef _KERNEL
#include "asf.h"
/* Name of the head of the linker file list in /sys/kern/kern_linker.c */
#define LINKER_HEAD "linker_files"
/*
* Get the list of linker files using kvm(3).
* Can work with a live kernel as well as with a crash dump.
*/
void
asf_kvm(const char *kernfile, const char *corefile)
{
char errbuf[LINE_MAX];
char name[PATH_MAX];
kvm_t *kd;
struct nlist nl[2];
struct linker_file lf;
linker_file_list_t linker_files;
ssize_t n;
void *kp;
kd = kvm_openfiles(kernfile, corefile, NULL, O_RDONLY, errbuf);
if (kd == NULL)
errx(2, "open kernel memory: %s", errbuf);
/*
* Locate the head of the linker file list using kernel symbols.
*/
strcpy(name, LINKER_HEAD);
nl[0].n_name = name; /* can't use LINKER_HEAD here because it's const */
nl[1].n_name = NULL; /* terminate the array for kvm_nlist() */
switch (kvm_nlist(kd, nl)) {
case 0:
break;
case -1:
warnx("%s: %s", LINKER_HEAD, kvm_geterr(kd));
kvm_close(kd);
exit(2);
default:
kvm_close(kd);
errx(2, "%s: symbol not found", LINKER_HEAD);
}
/*
* Read the head of the linker file list from kernel memory.
*/
n = kvm_read(kd, nl[0].n_value, &linker_files, sizeof(linker_files));
if (n == -1)
goto read_err;
if (n != sizeof(linker_files)) {
kvm_close(kd);
errx(2, "%s: short read", LINKER_HEAD);
}
/*
* Traverse the linker file list starting at its head.
*/
for (kp = linker_files.tqh_first; kp; kp = lf.link.tqe_next) {
/* Read a linker file structure */
n = kvm_read(kd, (u_long)kp, &lf, sizeof(lf));
if (n == -1)
goto read_err;
if (n != sizeof(lf)) {
kvm_close(kd);
errx(2, "kvm: short read");
}
/* Read the name of the file stored separately */
bzero(name, sizeof(name));
n = kvm_read(kd, (u_long)lf.filename, name, sizeof(name) - 1);
if (n == -1)
goto read_err;
if (strcmp(name, KERNFILE) == 0)
continue;
/* Add this file to our list of linker files */
kfile_add(name, lf.address);
}
kvm_close(kd);
return;
read_err: /* A common error case */
warnx("read kernel memory: %s", kvm_geterr(kd));
kvm_close(kd);
exit(2);
}
