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/*
* Copyright (c) 2004 Marcel Moolenaar
* 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 ``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 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/param.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <kvm.h>
#include <libgen.h>
#include <defs.h>
#include <command.h>
#include <completer.h>
#include <environ.h>
#include <exec.h>
#include <frame-unwind.h>
#include <inferior.h>
#include <objfiles.h>
#include <gdbcore.h>
#include <language.h>
#include <solist.h>
#include "kgdb.h"
struct lm_info {
CORE_ADDR base_address;
};
/* Offsets of fields in linker_file structure. */
static CORE_ADDR off_address, off_filename, off_pathname, off_next;
/* KVA of 'linker_path' which corresponds to the kern.module_path sysctl .*/
static CORE_ADDR module_path_addr;
static CORE_ADDR linker_files_addr;
static CORE_ADDR kernel_file_addr;
static struct target_so_ops kld_so_ops;
static int
kld_ok (char *path)
{
struct stat sb;
if (stat(path, &sb) == 0 && S_ISREG(sb.st_mode))
return (1);
return (0);
}
/*
* Look for a matching file checking for debug suffixes before the raw file:
* - filename + ".debug" (e.g. foo.ko.debug)
* - filename (e.g. foo.ko)
*/
static const char *kld_suffixes[] = {
".debug",
"",
NULL
};
static int
check_kld_path (char *path, size_t path_size)
{
const char **suffix;
char *ep;
ep = path + strlen(path);
suffix = kld_suffixes;
while (*suffix != NULL) {
if (strlcat(path, *suffix, path_size) < path_size) {
if (kld_ok(path))
return (1);
}
/* Restore original path to remove suffix. */
*ep = '\0';
suffix++;
}
return (0);
}
/*
* Try to find the path for a kld by looking in the kernel's directory and
* in the various paths in the module path.
*/
static int
find_kld_path (char *filename, char *path, size_t path_size)
{
char *module_path;
char *kernel_dir, *module_dir, *cp;
int error;
if (exec_bfd) {
kernel_dir = dirname(bfd_get_filename(exec_bfd));
if (kernel_dir != NULL) {
snprintf(path, path_size, "%s/%s", kernel_dir,
filename);
if (check_kld_path(path, path_size))
return (1);
}
}
if (module_path_addr != 0) {
target_read_string(module_path_addr, &module_path, PATH_MAX,
&error);
if (error == 0) {
make_cleanup(xfree, module_path);
cp = module_path;
while ((module_dir = strsep(&cp, ";")) != NULL) {
snprintf(path, path_size, "%s/%s", module_dir,
filename);
if (check_kld_path(path, path_size))
return (1);
}
}
}
return (0);
}
/*
* Read a kernel pointer given a KVA in 'address'.
*/
static CORE_ADDR
read_pointer (CORE_ADDR address)
{
CORE_ADDR value;
if (target_read_memory(address, (char *)&value, TARGET_PTR_BIT / 8) !=
0)
return (0);
return (extract_unsigned_integer(&value, TARGET_PTR_BIT / 8));
}
/*
* Try to find this kld in the kernel linker's list of linker files.
*/
static int
find_kld_address (char *arg, CORE_ADDR *address)
{
CORE_ADDR kld;
char *kld_filename;
char *filename;
int error;
if (linker_files_addr == 0 || off_address == 0 || off_filename == 0 ||
off_next == 0)
return (0);
filename = basename(arg);
for (kld = read_pointer(linker_files_addr); kld != 0;
kld = read_pointer(kld + off_next)) {
/* Try to read this linker file's filename. */
target_read_string(read_pointer(kld + off_filename),
&kld_filename, PATH_MAX, &error);
if (error)
continue;
/* Compare this kld's filename against our passed in name. */
if (strcmp(kld_filename, filename) != 0) {
xfree(kld_filename);
continue;
}
xfree(kld_filename);
/*
* We found a match, use its address as the base
* address if we can read it.
*/
*address = read_pointer(kld + off_address);
if (*address == 0)
return (0);
return (1);
}
return (0);
}
static void
load_kld (char *path, CORE_ADDR base_addr, int from_tty)
{
struct section_addr_info *sap;
struct section_table *sections = NULL, *sections_end = NULL, *s;
struct cleanup *cleanup;
bfd *bfd;
int i;
/* Open the kld. */
bfd = bfd_openr(path, gnutarget);
if (bfd == NULL)
error("\"%s\": can't open: %s", path,
bfd_errmsg(bfd_get_error()));
cleanup = make_cleanup_bfd_close(bfd);
if (!bfd_check_format(bfd, bfd_object))
error("\%s\": not an object file", path);
/* Make sure we have a .text section. */
if (bfd_get_section_by_name (bfd, ".text") == NULL)
error("\"%s\": can't find text section", path);
/* Build a section table from the bfd and relocate the sections. */
if (build_section_table (bfd, §ions, §ions_end))
error("\"%s\": can't find file sections", path);
cleanup = make_cleanup(xfree, sections);
for (s = sections; s < sections_end; s++) {
s->addr += base_addr;
s->endaddr += base_addr;
}
/* Build a section addr info to pass to symbol_file_add(). */
sap = build_section_addr_info_from_section_table (sections,
sections_end);
cleanup = make_cleanup((make_cleanup_ftype *)free_section_addr_info,
sap);
printf_unfiltered("add symbol table from file \"%s\" at\n", path);
for (i = 0; i < sap->num_sections; i++)
printf_unfiltered("\t%s_addr = %s\n", sap->other[i].name,
local_hex_string(sap->other[i].addr));
if (from_tty && (!query("%s", "")))
error("Not confirmed.");
symbol_file_add(path, from_tty, sap, 0, OBJF_USERLOADED);
do_cleanups(cleanup);
}
static void
kgdb_add_kld_cmd (char *arg, int from_tty)
{
char path[PATH_MAX];
CORE_ADDR base_addr;
if (!exec_bfd)
error("No kernel symbol file");
/* Try to open the raw path to handle absolute paths first. */
snprintf(path, sizeof(path), "%s", arg);
if (!check_kld_path(path, sizeof(path))) {
/*
* If that didn't work, look in the various possible
* paths for the module.
*/
if (!find_kld_path(arg, path, sizeof(path))) {
error("Unable to locate kld");
return;
}
}
if (!find_kld_address(arg, &base_addr)) {
error("Unable to find kld in kernel");
return;
}
load_kld(path, base_addr, from_tty);
reinit_frame_cache();
}
static void
kld_relocate_section_addresses (struct so_list *so, struct section_table *sec)
{
sec->addr += so->lm_info->base_address;
sec->endaddr += so->lm_info->base_address;
}
static void
kld_free_so (struct so_list *so)
{
xfree(so->lm_info);
}
static void
kld_clear_solib (void)
{
}
static void
kld_solib_create_inferior_hook (void)
{
}
static void
kld_special_symbol_handling (void)
{
}
static struct so_list *
kld_current_sos (void)
{
struct so_list *head, **prev, *new;
CORE_ADDR kld, kernel;
char *path;
int error;
if (linker_files_addr == 0 || kernel_file_addr == 0 ||
off_address == 0 || off_filename == 0 || off_next == 0)
return (NULL);
head = NULL;
prev = &head;
/*
* Walk the list of linker files creating so_list entries for
* each non-kernel file.
*/
kernel = read_pointer(kernel_file_addr);
for (kld = read_pointer(linker_files_addr); kld != 0;
kld = read_pointer(kld + off_next)) {
/* Skip the main kernel file. */
if (kld == kernel)
continue;
new = xmalloc(sizeof(*new));
memset(new, 0, sizeof(*new));
new->lm_info = xmalloc(sizeof(*new->lm_info));
new->lm_info->base_address = 0;
/* Read the base filename and store it in so_original_name. */
target_read_string(read_pointer(kld + off_filename),
&path, sizeof(new->so_original_name), &error);
if (error != 0) {
warning("kld_current_sos: Can't read filename: %s\n",
safe_strerror(error));
free_so(new);
continue;
}
strlcpy(new->so_original_name, path,
sizeof(new->so_original_name));
xfree(path);
/*
* Try to read the pathname (if it exists) and store
* it in so_name.
*/
if (off_pathname != 0) {
target_read_string(read_pointer(kld + off_pathname),
&path, sizeof(new->so_name), &error);
if (error != 0) {
warning(
"kld_current_sos: Can't read pathname for \"%s\": %s\n",
new->so_original_name,
safe_strerror(error));
strlcpy(new->so_name, new->so_original_name,
sizeof(new->so_name));
} else {
strlcpy(new->so_name, path,
sizeof(new->so_name));
xfree(path);
}
} else
strlcpy(new->so_name, new->so_original_name,
sizeof(new->so_name));
/* Read this kld's base address. */
new->lm_info->base_address = read_pointer(kld + off_address);
if (new->lm_info->base_address == 0) {
warning(
"kld_current_sos: Invalid address for kld \"%s\"",
new->so_original_name);
free_so(new);
continue;
}
/* Append to the list. */
*prev = new;
prev = &new->next;
}
return (head);
}
static int
kld_open_symbol_file_object (void *from_ttyp)
{
return (0);
}
static int
kld_in_dynsym_resolve_code (CORE_ADDR pc)
{
return (0);
}
static int
kld_find_and_open_solib (char *solib, unsigned o_flags, char **temp_pathname)
{
char path[PATH_MAX];
int fd;
*temp_pathname = NULL;
if (!find_kld_path(solib, path, sizeof(path))) {
errno = ENOENT;
return (-1);
}
fd = open(path, o_flags, 0);
if (fd >= 0)
*temp_pathname = xstrdup(path);
return (fd);
}
void
kld_new_objfile (struct objfile *objfile)
{
if (!have_partial_symbols())
return;
/*
* Compute offsets of relevant members in struct linker_file
* and the addresses of global variables. Don't warn about
* kernels that don't have 'pathname' in the linker_file
* struct since 6.x kernels don't have it.
*/
off_address = kgdb_parse("&((struct linker_file *)0)->address");
off_filename = kgdb_parse("&((struct linker_file *)0)->filename");
off_pathname = kgdb_parse_quiet("&((struct linker_file *)0)->pathname");
off_next = kgdb_parse("&((struct linker_file *)0)->link.tqe_next");
module_path_addr = kgdb_parse("linker_path");
linker_files_addr = kgdb_parse("&linker_files.tqh_first");
kernel_file_addr = kgdb_parse("&linker_kernel_file");
}
static int
load_klds_stub (void *arg)
{
SOLIB_ADD(NULL, 1, ¤t_target, auto_solib_add);
return (0);
}
void
kld_init (void)
{
catch_errors(load_klds_stub, NULL, NULL, RETURN_MASK_ALL);
}
void
initialize_kld_target(void)
{
struct cmd_list_element *c;
kld_so_ops.relocate_section_addresses = kld_relocate_section_addresses;
kld_so_ops.free_so = kld_free_so;
kld_so_ops.clear_solib = kld_clear_solib;
kld_so_ops.solib_create_inferior_hook = kld_solib_create_inferior_hook;
kld_so_ops.special_symbol_handling = kld_special_symbol_handling;
kld_so_ops.current_sos = kld_current_sos;
kld_so_ops.open_symbol_file_object = kld_open_symbol_file_object;
kld_so_ops.in_dynsym_resolve_code = kld_in_dynsym_resolve_code;
kld_so_ops.find_and_open_solib = kld_find_and_open_solib;
current_target_so_ops = &kld_so_ops;
c = add_com("add-kld", class_files, kgdb_add_kld_cmd,
"Usage: add-kld FILE\n\
Load the symbols from the kernel loadable module FILE.");
set_cmd_completer(c, filename_completer);
}
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