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kernel / pub / scm / linux / kernel / git / mmarek / kmod / 450bd1b4290e0dec65397881a7037090f203045a / . / libkmod / libkmod-module.c
blob: 1d90f3438623082491ce4bd362de7cb91059fbaa [file] [log] [blame]
/*
* libkmod - interface to kernel module operations
*
* Copyright (C) 2011-2013 ProFUSION embedded systems
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <stddef.h>
#include <stdarg.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <ctype.h>
#include <inttypes.h>
#include <limits.h>
#include <dirent.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/mman.h>
#include <sys/syscall.h>
#include <sys/wait.h>
#include <fnmatch.h>
#ifdef HAVE_LINUX_MODULE_H
#include <linux/module.h>
#endif
#include "libkmod.h"
#include "libkmod-internal.h"
/**
* SECTION:libkmod-module
* @short_description: operate on kernel modules
*/
/**
* kmod_module:
*
* Opaque object representing a module.
*/
struct kmod_module {
struct kmod_ctx *ctx;
char *hashkey;
char *name;
char *path;
struct kmod_list *dep;
char *options;
const char *install_commands; /* owned by kmod_config */
const char *remove_commands; /* owned by kmod_config */
char *alias; /* only set if this module was created from an alias */
struct kmod_file *file;
int n_dep;
int refcount;
struct {
bool dep : 1;
bool options : 1;
bool install_commands : 1;
bool remove_commands : 1;
} init;
/*
* private field used by kmod_module_get_probe_list() to detect
* dependency loops
*/
bool visited : 1;
/*
* set by kmod_module_get_probe_list: indicates for probe_insert()
* whether the module's command and softdep should be ignored
*/
bool ignorecmd : 1;
/*
* set by kmod_module_get_probe_list: indicates whether this is the
* module the user asked for or its dependency, or whether this
* is a softdep only
*/
bool required : 1;
/*
* if module was created by searching the modules.builtin file, this
* is set. There's nothing much useful one can do with such a
* "module", except knowing it's builtin.
*/
bool builtin : 1;
};
static inline const char *path_join(const char *path, size_t prefixlen,
char buf[PATH_MAX])
{
size_t pathlen;
if (path[0] == '/')
return path;
pathlen = strlen(path);
if (prefixlen + pathlen + 1 >= PATH_MAX)
return NULL;
memcpy(buf + prefixlen, path, pathlen + 1);
return buf;
}
static inline bool module_is_inkernel(struct kmod_module *mod)
{
int state = kmod_module_get_initstate(mod);
if (state == KMOD_MODULE_LIVE ||
state == KMOD_MODULE_BUILTIN)
return true;
return false;
}
int kmod_module_parse_depline(struct kmod_module *mod, char *line)
{
struct kmod_ctx *ctx = mod->ctx;
struct kmod_list *list = NULL;
const char *dirname;
char buf[PATH_MAX];
char *p, *saveptr;
int err = 0, n = 0;
size_t dirnamelen;
if (mod->init.dep)
return mod->n_dep;
assert(mod->dep == NULL);
mod->init.dep = true;
p = strchr(line, ':');
if (p == NULL)
return 0;
*p = '\0';
dirname = kmod_get_dirname(mod->ctx);
dirnamelen = strlen(dirname);
if (dirnamelen + 2 >= PATH_MAX)
return 0;
memcpy(buf, dirname, dirnamelen);
buf[dirnamelen] = '/';
dirnamelen++;
buf[dirnamelen] = '\0';
if (mod->path == NULL) {
const char *str = path_join(line, dirnamelen, buf);
if (str == NULL)
return 0;
mod->path = strdup(str);
if (mod->path == NULL)
return 0;
}
p++;
for (p = strtok_r(p, " \t", &saveptr); p != NULL;
p = strtok_r(NULL, " \t", &saveptr)) {
struct kmod_module *depmod;
const char *path;
path = path_join(p, dirnamelen, buf);
if (path == NULL) {
ERR(ctx, "could not join path '%s' and '%s'.\n",
dirname, p);
goto fail;
}
err = kmod_module_new_from_path(ctx, path, &depmod);
if (err < 0) {
ERR(ctx, "ctx=%p path=%s error=%s\n",
ctx, path, strerror(-err));
goto fail;
}
DBG(ctx, "add dep: %s\n", path);
list = kmod_list_prepend(list, depmod);
n++;
}
DBG(ctx, "%d dependencies for %s\n", n, mod->name);
mod->dep = list;
mod->n_dep = n;
return n;
fail:
kmod_module_unref_list(list);
mod->init.dep = false;
return err;
}
void kmod_module_set_visited(struct kmod_module *mod, bool visited)
{
mod->visited = visited;
}
void kmod_module_set_builtin(struct kmod_module *mod, bool builtin)
{
mod->builtin = builtin;
}
void kmod_module_set_required(struct kmod_module *mod, bool required)
{
mod->required = required;
}
/*
* Memory layout with alias:
*
* struct kmod_module {
* hashkey -----.
* alias -----. |
* name ----. | |
* } | | |
* name <----------' | |
* alias <-----------' |
* name\alias <--------'
*
* Memory layout without alias:
*
* struct kmod_module {
* hashkey ---.
* alias -----|----> NULL
* name ----. |
* } | |
* name <----------'-'
*
* @key is "name\alias" or "name" (in which case alias == NULL)
*/
static int kmod_module_new(struct kmod_ctx *ctx, const char *key,
const char *name, size_t namelen,
const char *alias, size_t aliaslen,
struct kmod_module **mod)
{
struct kmod_module *m;
size_t keylen;
m = kmod_pool_get_module(ctx, key);
if (m != NULL) {
*mod = kmod_module_ref(m);
return 0;
}
if (alias == NULL)
keylen = namelen;
else
keylen = namelen + aliaslen + 1;
m = malloc(sizeof(*m) + (alias == NULL ? 1 : 2) * (keylen + 1));
if (m == NULL)
return -ENOMEM;
memset(m, 0, sizeof(*m));
m->ctx = kmod_ref(ctx);
m->name = (char *)m + sizeof(*m);
memcpy(m->name, key, keylen + 1);
if (alias == NULL) {
m->hashkey = m->name;
m->alias = NULL;
} else {
m->name[namelen] = '\0';
m->alias = m->name + namelen + 1;
m->hashkey = m->name + keylen + 1;
memcpy(m->hashkey, key, keylen + 1);
}
m->refcount = 1;
kmod_pool_add_module(ctx, m, m->hashkey);
*mod = m;
return 0;
}
/**
* kmod_module_new_from_name:
* @ctx: kmod library context
* @name: name of the module
* @mod: where to save the created struct kmod_module
*
* Create a new struct kmod_module using the module name. @name can not be an
* alias, file name or anything else; it must be a module name. There's no
* check if the module exists in the system.
*
* This function is also used internally by many others that return a new
* struct kmod_module or a new list of modules.
*
* The initial refcount is 1, and needs to be decremented to release the
* resources of the kmod_module. Since libkmod keeps track of all
* kmod_modules created, they are all released upon @ctx destruction too. Do
* not unref @ctx before all the desired operations with the returned
* kmod_module are done.
*
* Returns: 0 on success or < 0 otherwise. It fails if name is not a valid
* module name or if memory allocation failed.
*/
KMOD_EXPORT int kmod_module_new_from_name(struct kmod_ctx *ctx,
const char *name,
struct kmod_module **mod)
{
size_t namelen;
char name_norm[PATH_MAX];
if (ctx == NULL || name == NULL || mod == NULL)
return -ENOENT;
modname_normalize(name, name_norm, &namelen);
return kmod_module_new(ctx, name_norm, name_norm, namelen, NULL, 0, mod);
}
int kmod_module_new_from_alias(struct kmod_ctx *ctx, const char *alias,
const char *name, struct kmod_module **mod)
{
int err;
char key[PATH_MAX];
size_t namelen = strlen(name);
size_t aliaslen = strlen(alias);
if (namelen + aliaslen + 2 > PATH_MAX)
return -ENAMETOOLONG;
memcpy(key, name, namelen);
memcpy(key + namelen + 1, alias, aliaslen + 1);
key[namelen] = '\\';
err = kmod_module_new(ctx, key, name, namelen, alias, aliaslen, mod);
if (err < 0)
return err;
return 0;
}
/**
* kmod_module_new_from_path:
* @ctx: kmod library context
* @path: path where to find the given module
* @mod: where to save the created struct kmod_module
*
* Create a new struct kmod_module using the module path. @path must be an
* existent file with in the filesystem and must be accessible to libkmod.
*
* The initial refcount is 1, and needs to be decremented to release the
* resources of the kmod_module. Since libkmod keeps track of all
* kmod_modules created, they are all released upon @ctx destruction too. Do
* not unref @ctx before all the desired operations with the returned
* kmod_module are done.
*
* If @path is relative, it's treated as relative to the current working
* directory. Otherwise, give an absolute path.
*
* Returns: 0 on success or < 0 otherwise. It fails if file does not exist, if
* it's not a valid file for a kmod_module or if memory allocation failed.
*/
KMOD_EXPORT int kmod_module_new_from_path(struct kmod_ctx *ctx,
const char *path,
struct kmod_module **mod)
{
struct kmod_module *m;
int err;
struct stat st;
char name[PATH_MAX];
char *abspath;
size_t namelen;
if (ctx == NULL || path == NULL || mod == NULL)
return -ENOENT;
abspath = path_make_absolute_cwd(path);
if (abspath == NULL) {
DBG(ctx, "no absolute path for %s\n", path);
return -ENOMEM;
}
err = stat(abspath, &st);
if (err < 0) {
err = -errno;
DBG(ctx, "stat %s: %s\n", path, strerror(errno));
free(abspath);
return err;
}
if (path_to_modname(path, name, &namelen) == NULL) {
DBG(ctx, "could not get modname from path %s\n", path);
free(abspath);
return -ENOENT;
}
m = kmod_pool_get_module(ctx, name);
if (m != NULL) {
if (m->path == NULL)
m->path = abspath;
else if (streq(m->path, abspath))
free(abspath);
else {
ERR(ctx, "kmod_module '%s' already exists with different path: new-path='%s' old-path='%s'\n",
name, abspath, m->path);
free(abspath);
return -EEXIST;
}
*mod = kmod_module_ref(m);
return 0;
}
err = kmod_module_new(ctx, name, name, namelen, NULL, 0, &m);
if (err < 0)
return err;
m->path = abspath;
*mod = m;
return 0;
}
/**
* kmod_module_unref:
* @mod: kmod module
*
* Drop a reference of the kmod module. If the refcount reaches zero, its
* resources are released.
*
* Returns: NULL if @mod is NULL or if the module was released. Otherwise it
* returns the passed @mod with its refcount decremented.
*/
KMOD_EXPORT struct kmod_module *kmod_module_unref(struct kmod_module *mod)
{
if (mod == NULL)
return NULL;
if (--mod->refcount > 0)
return mod;
DBG(mod->ctx, "kmod_module %p released\n", mod);
kmod_pool_del_module(mod->ctx, mod, mod->hashkey);
kmod_module_unref_list(mod->dep);
if (mod->file)
kmod_file_unref(mod->file);
kmod_unref(mod->ctx);
free(mod->options);
free(mod->path);
free(mod);
return NULL;
}
/**
* kmod_module_ref:
* @mod: kmod module
*
* Take a reference of the kmod module, incrementing its refcount.
*
* Returns: the passed @module with its refcount incremented.
*/
KMOD_EXPORT struct kmod_module *kmod_module_ref(struct kmod_module *mod)
{
if (mod == NULL)
return NULL;
mod->refcount++;
return mod;
}
#define CHECK_ERR_AND_FINISH(_err, _label_err, _list, label_finish) \
do { \
if ((_err) < 0) \
goto _label_err; \
if (*(_list) != NULL) \
goto finish; \
} while (0)
/**
* kmod_module_new_from_lookup:
* @ctx: kmod library context
* @given_alias: alias to look for
* @list: an empty list where to save the list of modules matching
* @given_alias
*
* Create a new list of kmod modules using an alias or module name and lookup
* libkmod's configuration files and indexes in order to find the module.
* Once it's found in one of the places, it stops searching and create the
* list of modules that is saved in @list.
*
* The search order is: 1. aliases in configuration file; 2. module names in
* modules.dep index; 3. symbol aliases in modules.symbols index; 4. aliases
* in modules.alias index.
*
* The initial refcount is 1, and needs to be decremented to release the
* resources of the kmod_module. The returned @list must be released by
* calling kmod_module_unref_list(). Since libkmod keeps track of all
* kmod_modules created, they are all released upon @ctx destruction too. Do
* not unref @ctx before all the desired operations with the returned list are
* completed.
*
* Returns: 0 on success or < 0 otherwise. It fails if any of the lookup
* methods failed, which is basically due to memory allocation fail. If module
* is not found, it still returns 0, but @list is an empty list.
*/
KMOD_EXPORT int kmod_module_new_from_lookup(struct kmod_ctx *ctx,
const char *given_alias,
struct kmod_list **list)
{
int err;
char alias[PATH_MAX];
if (ctx == NULL || given_alias == NULL)
return -ENOENT;
if (list == NULL || *list != NULL) {
ERR(ctx, "An empty list is needed to create lookup\n");
return -ENOSYS;
}
if (alias_normalize(given_alias, alias, NULL) < 0) {
DBG(ctx, "invalid alias: %s\n", given_alias);
return -EINVAL;
}
DBG(ctx, "input alias=%s, normalized=%s\n", given_alias, alias);
/* Aliases from config file override all the others */
err = kmod_lookup_alias_from_config(ctx, alias, list);
CHECK_ERR_AND_FINISH(err, fail, list, finish);
DBG(ctx, "lookup modules.dep %s\n", alias);
err = kmod_lookup_alias_from_moddep_file(ctx, alias, list);
CHECK_ERR_AND_FINISH(err, fail, list, finish);
DBG(ctx, "lookup modules.symbols %s\n", alias);
err = kmod_lookup_alias_from_symbols_file(ctx, alias, list);
CHECK_ERR_AND_FINISH(err, fail, list, finish);
DBG(ctx, "lookup install and remove commands %s\n", alias);
err = kmod_lookup_alias_from_commands(ctx, alias, list);
CHECK_ERR_AND_FINISH(err, fail, list, finish);
DBG(ctx, "lookup modules.aliases %s\n", alias);
err = kmod_lookup_alias_from_aliases_file(ctx, alias, list);
CHECK_ERR_AND_FINISH(err, fail, list, finish);
DBG(ctx, "lookup modules.builtin %s\n", alias);
err = kmod_lookup_alias_from_builtin_file(ctx, alias, list);
CHECK_ERR_AND_FINISH(err, fail, list, finish);
finish:
DBG(ctx, "lookup %s=%d, list=%p\n", alias, err, *list);
return err;
fail:
DBG(ctx, "Failed to lookup %s\n", alias);
kmod_module_unref_list(*list);
*list = NULL;
return err;
}
#undef CHECK_ERR_AND_FINISH
/**
* kmod_module_unref_list:
* @list: list of kmod modules
*
* Drop a reference of each kmod module in @list and releases the resources
* taken by the list itself.
*
* Returns: 0
*/
KMOD_EXPORT int kmod_module_unref_list(struct kmod_list *list)
{
for (; list != NULL; list = kmod_list_remove(list))
kmod_module_unref(list->data);
return 0;
}
/**
* kmod_module_get_filtered_blacklist:
* @ctx: kmod library context
* @input: list of kmod_module to be filtered with blacklist
* @output: where to save the new list
*
* This function should not be used. Use kmod_module_apply_filter instead.
*
* Given a list @input, this function filter it out with config's blacklist
* and save it in @output.
*
* Returns: 0 on success or < 0 otherwise. @output is saved with the updated
* list.
*/
KMOD_EXPORT int kmod_module_get_filtered_blacklist(const struct kmod_ctx *ctx,
const struct kmod_list *input,
struct kmod_list **output)
{
return kmod_module_apply_filter(ctx, KMOD_FILTER_BLACKLIST, input, output);
}
static const struct kmod_list *module_get_dependencies_noref(const struct kmod_module *mod)
{
if (!mod->init.dep) {
/* lazy init */
char *line = kmod_search_moddep(mod->ctx, mod->name);
if (line == NULL)
return NULL;
kmod_module_parse_depline((struct kmod_module *)mod, line);
free(line);
if (!mod->init.dep)
return NULL;
}
return mod->dep;
}
/**
* kmod_module_get_dependencies:
* @mod: kmod module
*
* Search the modules.dep index to find the dependencies of the given @mod.
* The result is cached in @mod, so subsequent calls to this function will
* return the already searched list of modules.
*
* Returns: NULL on failure. Otherwise it returns a list of kmod modules
* that can be released by calling kmod_module_unref_list().
*/
KMOD_EXPORT struct kmod_list *kmod_module_get_dependencies(const struct kmod_module *mod)
{
struct kmod_list *l, *l_new, *list_new = NULL;
if (mod == NULL)
return NULL;
module_get_dependencies_noref(mod);
kmod_list_foreach(l, mod->dep) {
l_new = kmod_list_append(list_new, kmod_module_ref(l->data));
if (l_new == NULL) {
kmod_module_unref(l->data);
goto fail;
}
list_new = l_new;
}
return list_new;
fail:
ERR(mod->ctx, "out of memory\n");
kmod_module_unref_list(list_new);
return NULL;
}
/**
* kmod_module_get_module:
* @entry: an entry in a list of kmod modules.
*
* Get the kmod module of this @entry in the list, increasing its refcount.
* After it's used, unref it. Since the refcount is incremented upon return,
* you still have to call kmod_module_unref_list() to release the list of kmod
* modules.
*
* Returns: NULL on failure or the kmod_module contained in this list entry
* with its refcount incremented.
*/
KMOD_EXPORT struct kmod_module *kmod_module_get_module(const struct kmod_list *entry)
{
if (entry == NULL)
return NULL;
return kmod_module_ref(entry->data);
}
/**
* kmod_module_get_name:
* @mod: kmod module
*
* Get the name of this kmod module. Name is always available, independently
* if it was created by kmod_module_new_from_name() or another function and
* it's always normalized (dashes are replaced with underscores).
*
* Returns: the name of this kmod module.
*/
KMOD_EXPORT const char *kmod_module_get_name(const struct kmod_module *mod)
{
if (mod == NULL)
return NULL;
return mod->name;
}
/**
* kmod_module_get_path:
* @mod: kmod module
*
* Get the path of this kmod module. If this kmod module was not created by
* path, it can search the modules.dep index in order to find out the module
* under context's dirname.
*
* Returns: the path of this kmod module or NULL if such information is not
* available.
*/
KMOD_EXPORT const char *kmod_module_get_path(const struct kmod_module *mod)
{
char *line;
if (mod == NULL)
return NULL;
DBG(mod->ctx, "name='%s' path='%s'\n", mod->name, mod->path);
if (mod->path != NULL)
return mod->path;
if (mod->init.dep)
return NULL;
/* lazy init */
line = kmod_search_moddep(mod->ctx, mod->name);
if (line == NULL)
return NULL;
kmod_module_parse_depline((struct kmod_module *) mod, line);
free(line);
return mod->path;
}
extern long delete_module(const char *name, unsigned int flags);
/**
* kmod_module_remove_module:
* @mod: kmod module
* @flags: flags to pass to Linux kernel when removing the module. The only valid flag is
* KMOD_REMOVE_FORCE: force remove module regardless if it's still in
* use by a kernel subsystem or other process;
* KMOD_REMOVE_NOWAIT is always enforced, causing us to pass O_NONBLOCK to
* delete_module(2).
*
* Remove a module from Linux kernel.
*
* Returns: 0 on success or < 0 on failure.
*/
KMOD_EXPORT int kmod_module_remove_module(struct kmod_module *mod,
unsigned int flags)
{
int err;
if (mod == NULL)
return -ENOENT;
/* Filter out other flags and force ONONBLOCK */
flags &= KMOD_REMOVE_FORCE;
flags |= KMOD_REMOVE_NOWAIT;
err = delete_module(mod->name, flags);
if (err != 0) {
err = -errno;
ERR(mod->ctx, "could not remove '%s': %m\n", mod->name);
}
return err;
}
extern long init_module(const void *mem, unsigned long len, const char *args);
/**
* kmod_module_insert_module:
* @mod: kmod module
* @flags: flags are not passed to Linux Kernel, but instead they dictate the
* behavior of this function, valid flags are
* KMOD_INSERT_FORCE_VERMAGIC: ignore kernel version magic;
* KMOD_INSERT_FORCE_MODVERSION: ignore symbol version hashes.
* @options: module's options to pass to Linux Kernel.
*
* Insert a module in Linux kernel. It opens the file pointed by @mod,
* mmap'ing it and passing to kernel.
*
* Returns: 0 on success or < 0 on failure. If module is already loaded it
* returns -EEXIST.
*/
KMOD_EXPORT int kmod_module_insert_module(struct kmod_module *mod,
unsigned int flags,
const char *options)
{
int err;
const void *mem;
off_t size;
struct kmod_elf *elf;
const char *path;
const char *args = options ? options : "";
if (mod == NULL)
return -ENOENT;
path = kmod_module_get_path(mod);
if (path == NULL) {
ERR(mod->ctx, "could not find module by name='%s'\n", mod->name);
return -ENOSYS;
}
mod->file = kmod_file_open(mod->ctx, path);
if (mod->file == NULL) {
err = -errno;
return err;
}
if (kmod_file_get_direct(mod->file)) {
unsigned int kernel_flags = 0;
if (flags & KMOD_INSERT_FORCE_VERMAGIC)
kernel_flags |= MODULE_INIT_IGNORE_VERMAGIC;
if (flags & KMOD_INSERT_FORCE_MODVERSION)
kernel_flags |= MODULE_INIT_IGNORE_MODVERSIONS;
err = finit_module(kmod_file_get_fd(mod->file), args, kernel_flags);
if (err == 0 || errno != ENOSYS)
goto init_finished;
}
if (flags & (KMOD_INSERT_FORCE_VERMAGIC | KMOD_INSERT_FORCE_MODVERSION)) {
elf = kmod_file_get_elf(mod->file);
if (elf == NULL) {
err = -errno;
return err;
}
if (flags & KMOD_INSERT_FORCE_MODVERSION) {
err = kmod_elf_strip_section(elf, "__versions");
if (err < 0)
INFO(mod->ctx, "Failed to strip modversion: %s\n", strerror(-err));
}
if (flags & KMOD_INSERT_FORCE_VERMAGIC) {
err = kmod_elf_strip_vermagic(elf);
if (err < 0)
INFO(mod->ctx, "Failed to strip vermagic: %s\n", strerror(-err));
}
mem = kmod_elf_get_memory(elf);
} else {
mem = kmod_file_get_contents(mod->file);
}
size = kmod_file_get_size(mod->file);
err = init_module(mem, size, args);
init_finished:
if (err < 0) {
err = -errno;
INFO(mod->ctx, "Failed to insert module '%s': %m\n", path);
}
return err;
}
static bool module_is_blacklisted(struct kmod_module *mod)
{
struct kmod_ctx *ctx = mod->ctx;
const struct kmod_config *config = kmod_get_config(ctx);
const struct kmod_list *bl = config->blacklists;
const struct kmod_list *l;
kmod_list_foreach(l, bl) {
const char *modname = kmod_blacklist_get_modname(l);
if (streq(modname, mod->name))
return true;
}
return false;
}
/**
* kmod_module_apply_filter
* @ctx: kmod library context
* @filter_type: bitmask to filter modules out, valid types are
* KMOD_FILTER_BLACKLIST: filter modules in blacklist out;
* KMOD_FILTER_BUILTIN: filter builtin modules out.
* @input: list of kmod_module to be filtered
* @output: where to save the new list
*
* Given a list @input, this function filter it out by the filter mask
* and save it in @output.
*
* Returns: 0 on success or < 0 otherwise. @output is saved with the updated
* list.
*/
KMOD_EXPORT int kmod_module_apply_filter(const struct kmod_ctx *ctx,
enum kmod_filter filter_type,
const struct kmod_list *input,
struct kmod_list **output)
{
const struct kmod_list *li;
if (ctx == NULL || output == NULL)
return -ENOENT;
*output = NULL;
if (input == NULL)
return 0;
kmod_list_foreach(li, input) {
struct kmod_module *mod = li->data;
struct kmod_list *node;
if ((filter_type & KMOD_FILTER_BLACKLIST) &&
module_is_blacklisted(mod))
continue;
if ((filter_type & KMOD_FILTER_BUILTIN) && mod->builtin)
continue;
node = kmod_list_append(*output, mod);
if (node == NULL)
goto fail;
*output = node;
kmod_module_ref(mod);
}
return 0;
fail:
kmod_module_unref_list(*output);
*output = NULL;
return -ENOMEM;
}
static int command_do(struct kmod_module *mod, const char *type,
const char *cmd)
{
const char *modname = kmod_module_get_name(mod);
int err;
DBG(mod->ctx, "%s %s\n", type, cmd);
setenv("MODPROBE_MODULE", modname, 1);
err = system(cmd);
unsetenv("MODPROBE_MODULE");
if (err == -1 || WEXITSTATUS(err)) {
ERR(mod->ctx, "Error running %s command for %s\n",
type, modname);
if (err != -1)
err = -WEXITSTATUS(err);
}
return err;
}
struct probe_insert_cb {
int (*run_install)(struct kmod_module *m, const char *cmd, void *data);
void *data;
};
static int module_do_install_commands(struct kmod_module *mod,
const char *options,
struct probe_insert_cb *cb)
{
const char *command = kmod_module_get_install_commands(mod);
char *p;
_cleanup_free_ char *cmd;
int err;
size_t cmdlen, options_len, varlen;
assert(command);
if (options == NULL)
options = "";
options_len = strlen(options);
cmdlen = strlen(command);
varlen = sizeof("$CMDLINE_OPTS") - 1;
cmd = memdup(command, cmdlen + 1);
if (cmd == NULL)
return -ENOMEM;
while ((p = strstr(cmd, "$CMDLINE_OPTS")) != NULL) {
size_t prefixlen = p - cmd;
size_t suffixlen = cmdlen - prefixlen - varlen;
size_t slen = cmdlen - varlen + options_len;
char *suffix = p + varlen;
char *s = malloc(slen + 1);
if (!s)
return -ENOMEM;
memcpy(s, cmd, p - cmd);
memcpy(s + prefixlen, options, options_len);
memcpy(s + prefixlen + options_len, suffix, suffixlen);
s[slen] = '\0';
free(cmd);
cmd = s;
cmdlen = slen;
}
if (cb->run_install != NULL)
err = cb->run_install(mod, cmd, cb->data);
else
err = command_do(mod, "install", cmd);
return err;
}
static char *module_options_concat(const char *opt, const char *xopt)
{
// TODO: we might need to check if xopt overrides options on opt
size_t optlen = opt == NULL ? 0 : strlen(opt);
size_t xoptlen = xopt == NULL ? 0 : strlen(xopt);
char *r;
if (optlen == 0 && xoptlen == 0)
return NULL;
r = malloc(optlen + xoptlen + 2);
if (opt != NULL) {
memcpy(r, opt, optlen);
r[optlen] = ' ';
optlen++;
}
if (xopt != NULL)
memcpy(r + optlen, xopt, xoptlen);
r[optlen + xoptlen] = '\0';
return r;
}
static int __kmod_module_get_probe_list(struct kmod_module *mod,
bool required,
bool ignorecmd,
struct kmod_list **list);
/* re-entrant */
static int __kmod_module_fill_softdep(struct kmod_module *mod,
struct kmod_list **list)
{
struct kmod_list *pre = NULL, *post = NULL, *l;
int err;
err = kmod_module_get_softdeps(mod, &pre, &post);
if (err < 0) {
ERR(mod->ctx, "could not get softdep: %s\n",
strerror(-err));
goto fail;
}
kmod_list_foreach(l, pre) {
struct kmod_module *m = l->data;
err = __kmod_module_get_probe_list(m, false, false, list);
if (err < 0)
goto fail;
}
l = kmod_list_append(*list, kmod_module_ref(mod));
if (l == NULL) {
kmod_module_unref(mod);
err = -ENOMEM;
goto fail;
}
*list = l;
mod->ignorecmd = (pre != NULL || post != NULL);
kmod_list_foreach(l, post) {
struct kmod_module *m = l->data;
err = __kmod_module_get_probe_list(m, false, false, list);
if (err < 0)
goto fail;
}
fail:
kmod_module_unref_list(pre);
kmod_module_unref_list(post);
return err;
}
/* re-entrant */
static int __kmod_module_get_probe_list(struct kmod_module *mod,
bool required,
bool ignorecmd,
struct kmod_list **list)
{
struct kmod_list *dep, *l;
int err = 0;
if (mod->visited) {
DBG(mod->ctx, "Ignore module '%s': already visited\n",
mod->name);
return 0;
}
mod->visited = true;
dep = kmod_module_get_dependencies(mod);
if (required) {
/*
* Called from kmod_module_probe_insert_module(); set the
* ->required flag on mod and all its dependencies before
* they are possibly visited through some softdeps.
*/
mod->required = true;
kmod_list_foreach(l, dep) {
struct kmod_module *m = l->data;
m->required = true;
}
}
kmod_list_foreach(l, dep) {
struct kmod_module *m = l->data;
err = __kmod_module_fill_softdep(m, list);
if (err < 0)
goto finish;
}
if (ignorecmd) {
l = kmod_list_append(*list, kmod_module_ref(mod));
if (l == NULL) {
kmod_module_unref(mod);
err = -ENOMEM;
goto finish;
}
*list = l;
mod->ignorecmd = true;
} else
err = __kmod_module_fill_softdep(mod, list);
finish:
kmod_module_unref_list(dep);
return err;
}
static int kmod_module_get_probe_list(struct kmod_module *mod,
bool ignorecmd,
struct kmod_list **list)
{
int err;
assert(mod != NULL);
assert(list != NULL && *list == NULL);
/*
* Make sure we don't get screwed by previous calls to this function
*/
kmod_set_modules_visited(mod->ctx, false);
kmod_set_modules_required(mod->ctx, false);
err = __kmod_module_get_probe_list(mod, true, ignorecmd, list);
if (err < 0) {
kmod_module_unref_list(*list);
*list = NULL;
}
return err;
}
/**
* kmod_module_probe_insert_module:
* @mod: kmod module
* @flags: flags are not passed to Linux Kernel, but instead they dictate the
* behavior of this function, valid flags are
* KMOD_PROBE_FORCE_VERMAGIC: ignore kernel version magic;
* KMOD_PROBE_FORCE_MODVERSION: ignore symbol version hashes;
* KMOD_PROBE_IGNORE_COMMAND: whether the probe should ignore install
* commands and softdeps configured in the system;
* KMOD_PROBE_IGNORE_LOADED: do not check whether the module is already
* live in kernel or not;
* KMOD_PROBE_DRY_RUN: dry run, do not insert module, just call the
* associated callback function;
* KMOD_PROBE_FAIL_ON_LOADED: if KMOD_PROBE_IGNORE_LOADED is not specified
* and the module is already live in kernel, the function will fail if this
* flag is specified;
* KMOD_PROBE_APPLY_BLACKLIST_ALL: probe will apply KMOD_FILTER_BLACKLIST
* filter to this module and its dependencies. If any of the dependencies (or
* the module) is blacklisted, the probe will fail, unless the blacklisted
* module is already live in kernel;
* KMOD_PROBE_APPLY_BLACKLIST: probe will fail if the module is blacklisted;
* KMOD_PROBE_APPLY_BLACKLIST_ALIAS_ONLY: probe will fail if the module is an
* alias and is blacklisted.
* @extra_options: module's options to pass to Linux Kernel. It applies only
* to @mod, not to its dependencies.
* @run_install: function to run when @mod is backed by an install command.
* @data: data to give back to @run_install callback
* @print_action: function to call with the action being taken (install or
* insmod). It's useful for tools like modprobe when running with verbose
* output or in dry-run mode.
*
* Insert a module in Linux kernel resolving dependencies, soft dependencies,
* install commands and applying blacklist.
*
* If @run_install is NULL, this function will fork and exec by calling
* system(3). Don't pass a NULL argument in @run_install if your binary is
* setuid/setgid (see warning in system(3)). If you need control over the
* execution of an install command, give a callback function instead.
*
* Returns: 0 on success, > 0 if stopped by a reason given in @flags or < 0 on
* failure.
*/
KMOD_EXPORT int kmod_module_probe_insert_module(struct kmod_module *mod,
unsigned int flags, const char *extra_options,
int (*run_install)(struct kmod_module *m,
const char *cmd, void *data),
const void *data,
void (*print_action)(struct kmod_module *m,
bool install,
const char *options))
{
struct kmod_list *list = NULL, *l;
struct probe_insert_cb cb;
int err;
if (mod == NULL)
return -ENOENT;
if (!(flags & KMOD_PROBE_IGNORE_LOADED)
&& module_is_inkernel(mod)) {
if (flags & KMOD_PROBE_FAIL_ON_LOADED)
return -EEXIST;
else
return 0;
}
/*
* Ugly assignement + check. We need to check if we were told to check
* blacklist and also return the reason why we failed.
* KMOD_PROBE_APPLY_BLACKLIST_ALIAS_ONLY will take effect only if the
* module is an alias, so we also need to check it
*/
if ((mod->alias != NULL && ((err = flags & KMOD_PROBE_APPLY_BLACKLIST_ALIAS_ONLY)))
|| (err = flags & KMOD_PROBE_APPLY_BLACKLIST_ALL)
|| (err = flags & KMOD_PROBE_APPLY_BLACKLIST)) {
if (module_is_blacklisted(mod))
return err;
}
err = kmod_module_get_probe_list(mod,
!!(flags & KMOD_PROBE_IGNORE_COMMAND), &list);
if (err < 0)
return err;
if (flags & KMOD_PROBE_APPLY_BLACKLIST_ALL) {
struct kmod_list *filtered = NULL;
err = kmod_module_apply_filter(mod->ctx,
KMOD_FILTER_BLACKLIST, list, &filtered);
if (err < 0)
return err;
kmod_module_unref_list(list);
if (filtered == NULL)
return KMOD_PROBE_APPLY_BLACKLIST_ALL;
list = filtered;
}
cb.run_install = run_install;
cb.data = (void *) data;
kmod_list_foreach(l, list) {
struct kmod_module *m = l->data;
const char *moptions = kmod_module_get_options(m);
const char *cmd = kmod_module_get_install_commands(m);
char *options;
if (!(flags & KMOD_PROBE_IGNORE_LOADED)
&& module_is_inkernel(m)) {
DBG(mod->ctx, "Ignoring module '%s': already loaded\n",
m->name);
err = -EEXIST;
goto finish_module;
}
options = module_options_concat(moptions,
m == mod ? extra_options : NULL);
if (cmd != NULL && !m->ignorecmd) {
if (print_action != NULL)
print_action(m, true, options ?: "");
if (!(flags & KMOD_PROBE_DRY_RUN))
err = module_do_install_commands(m, options,
&cb);
} else {
if (print_action != NULL)
print_action(m, false, options ?: "");
if (!(flags & KMOD_PROBE_DRY_RUN))
err = kmod_module_insert_module(m, flags,
options);
}
free(options);
finish_module:
/*
* Treat "already loaded" error. If we were told to stop on
* already loaded and the module being loaded is not a softdep
* or dep, bail out. Otherwise, just ignore and continue.
*
* We need to check here because of race conditions. We
* checked first if module was already loaded but it may have
* been loaded between the check and the moment we try to
* insert it.
*/
if (err == -EEXIST && m == mod &&
(flags & KMOD_PROBE_FAIL_ON_LOADED))
break;
/*
* Ignore errors from softdeps
*/
if (err == -EEXIST || !m->required)
err = 0;
else if (err < 0)
break;
}
kmod_module_unref_list(list);
return err;
}
/**
* kmod_module_get_options:
* @mod: kmod module
*
* Get options of this kmod module. Options come from the configuration file
* and are cached in @mod. The first call to this function will search for
* this module in configuration and subsequent calls return the cached string.
*
* Returns: a string with all the options separated by spaces. This string is
* owned by @mod, do not free it.
*/
KMOD_EXPORT const char *kmod_module_get_options(const struct kmod_module *mod)
{
if (mod == NULL)
return NULL;
if (!mod->init.options) {
/* lazy init */
struct kmod_module *m = (struct kmod_module *)mod;
const struct kmod_list *l;
const struct kmod_config *config;
char *opts = NULL;
size_t optslen = 0;
config = kmod_get_config(mod->ctx);
kmod_list_foreach(l, config->options) {
const char *modname = kmod_option_get_modname(l);
const char *str;
size_t len;
void *tmp;
DBG(mod->ctx, "modname=%s mod->name=%s mod->alias=%s\n", modname, mod->name, mod->alias);
if (!(streq(modname, mod->name) || (mod->alias != NULL &&
streq(modname, mod->alias))))
continue;
DBG(mod->ctx, "passed = modname=%s mod->name=%s mod->alias=%s\n", modname, mod->name, mod->alias);
str = kmod_option_get_options(l);
len = strlen(str);
if (len < 1)
continue;
tmp = realloc(opts, optslen + len + 2);
if (tmp == NULL) {
free(opts);
goto failed;
}
opts = tmp;
if (optslen > 0) {
opts[optslen] = ' ';
optslen++;
}
memcpy(opts + optslen, str, len);
optslen += len;
opts[optslen] = '\0';
}
m->init.options = true;
m->options = opts;
}
return mod->options;
failed:
ERR(mod->ctx, "out of memory\n");
return NULL;
}
/**
* kmod_module_get_install_commands:
* @mod: kmod module
*
* Get install commands for this kmod module. Install commands come from the
* configuration file and are cached in @mod. The first call to this function
* will search for this module in configuration and subsequent calls return
* the cached string. The install commands are returned as they were in the
* configuration, concatenated by ';'. No other processing is made in this
* string.
*
* Returns: a string with all install commands separated by semicolons. This
* string is owned by @mod, do not free it.
*/
KMOD_EXPORT const char *kmod_module_get_install_commands(const struct kmod_module *mod)
{
if (mod == NULL)
return NULL;
if (!mod->init.install_commands) {
/* lazy init */
struct kmod_module *m = (struct kmod_module *)mod;
const struct kmod_list *l;
const struct kmod_config *config;
config = kmod_get_config(mod->ctx);
kmod_list_foreach(l, config->install_commands) {
const char *modname = kmod_command_get_modname(l);
if (fnmatch(modname, mod->name, 0) != 0)
continue;
m->install_commands = kmod_command_get_command(l);
/*
* find only the first command, as modprobe from
* module-init-tools does
*/
break;
}
m->init.install_commands = true;
}
return mod->install_commands;
}
void kmod_module_set_install_commands(struct kmod_module *mod, const char *cmd)
{
mod->init.install_commands = true;
mod->install_commands = cmd;
}
static struct kmod_list *lookup_softdep(struct kmod_ctx *ctx, const char * const * array, unsigned int count)
{
struct kmod_list *ret = NULL;
unsigned i;
for (i = 0; i < count; i++) {
const char *depname = array[i];
struct kmod_list *lst = NULL;
int err;
err = kmod_module_new_from_lookup(ctx, depname, &lst);
if (err < 0) {
ERR(ctx, "failed to lookup soft dependency '%s', continuing anyway.\n", depname);
continue;
} else if (lst != NULL)
ret = kmod_list_append_list(ret, lst);
}
return ret;
}
/**
* kmod_module_get_softdeps:
* @mod: kmod module
* @pre: where to save the list of preceding soft dependencies.
* @post: where to save the list of post soft dependencies.
*
* Get soft dependencies for this kmod module. Soft dependencies come
* from configuration file and are not cached in @mod because it may include
* dependency cycles that would make we leak kmod_module. Any call
* to this function will search for this module in configuration, allocate a
* list and return the result.
*
* Both @pre and @post are newly created list of kmod_module and
* should be unreferenced with kmod_module_unref_list().
*
* Returns: 0 on success or < 0 otherwise.
*/
KMOD_EXPORT int kmod_module_get_softdeps(const struct kmod_module *mod,
struct kmod_list **pre,
struct kmod_list **post)
{
const struct kmod_list *l;
const struct kmod_config *config;
if (mod == NULL || pre == NULL || post == NULL)
return -ENOENT;
assert(*pre == NULL);
assert(*post == NULL);
config = kmod_get_config(mod->ctx);
kmod_list_foreach(l, config->softdeps) {
const char *modname = kmod_softdep_get_name(l);
const char * const *array;
unsigned count;
if (fnmatch(modname, mod->name, 0) != 0)
continue;
array = kmod_softdep_get_pre(l, &count);
*pre = lookup_softdep(mod->ctx, array, count);
array = kmod_softdep_get_post(l, &count);
*post = lookup_softdep(mod->ctx, array, count);
/*
* find only the first command, as modprobe from
* module-init-tools does
*/
break;
}
return 0;
}
/**
* kmod_module_get_remove_commands:
* @mod: kmod module
*
* Get remove commands for this kmod module. Remove commands come from the
* configuration file and are cached in @mod. The first call to this function
* will search for this module in configuration and subsequent calls return
* the cached string. The remove commands are returned as they were in the
* configuration, concatenated by ';'. No other processing is made in this
* string.
*
* Returns: a string with all remove commands separated by semicolons. This
* string is owned by @mod, do not free it.
*/
KMOD_EXPORT const char *kmod_module_get_remove_commands(const struct kmod_module *mod)
{
if (mod == NULL)
return NULL;
if (!mod->init.remove_commands) {
/* lazy init */
struct kmod_module *m = (struct kmod_module *)mod;
const struct kmod_list *l;
const struct kmod_config *config;
config = kmod_get_config(mod->ctx);
kmod_list_foreach(l, config->remove_commands) {
const char *modname = kmod_command_get_modname(l);
if (fnmatch(modname, mod->name, 0) != 0)
continue;
m->remove_commands = kmod_command_get_command(l);
/*
* find only the first command, as modprobe from
* module-init-tools does
*/
break;
}
m->init.remove_commands = true;
}
return mod->remove_commands;
}
void kmod_module_set_remove_commands(struct kmod_module *mod, const char *cmd)
{
mod->init.remove_commands = true;
mod->remove_commands = cmd;
}
/**
* SECTION:libkmod-loaded
* @short_description: currently loaded modules
*
* Information about currently loaded modules, as reported by Linux kernel.
* These information are not cached by libkmod and are always read from /sys
* and /proc/modules.
*/
/**
* kmod_module_new_from_loaded:
* @ctx: kmod library context
* @list: where to save the list of loaded modules
*
* Create a new list of kmod modules with all modules currently loaded in
* kernel. It uses /proc/modules to get the names of loaded modules and to
* create kmod modules by calling kmod_module_new_from_name() in each of them.
* They are put in @list in no particular order.
*
* The initial refcount is 1, and needs to be decremented to release the
* resources of the kmod_module. The returned @list must be released by
* calling kmod_module_unref_list(). Since libkmod keeps track of all
* kmod_modules created, they are all released upon @ctx destruction too. Do
* not unref @ctx before all the desired operations with the returned list are
* completed.
*
* Returns: 0 on success or < 0 on error.
*/
KMOD_EXPORT int kmod_module_new_from_loaded(struct kmod_ctx *ctx,
struct kmod_list **list)
{
struct kmod_list *l = NULL;
FILE *fp;
char line[4096];
if (ctx == NULL || list == NULL)
return -ENOENT;
fp = fopen("/proc/modules", "re");
if (fp == NULL) {
int err = -errno;
ERR(ctx, "could not open /proc/modules: %s\n", strerror(errno));
return err;
}
while (fgets(line, sizeof(line), fp)) {
struct kmod_module *m;
struct kmod_list *node;
int err;
char *saveptr, *name = strtok_r(line, " \t", &saveptr);
err = kmod_module_new_from_name(ctx, name, &m);
if (err < 0) {
ERR(ctx, "could not get module from name '%s': %s\n",
name, strerror(-err));
continue;
}
node = kmod_list_append(l, m);
if (node)
l = node;
else {
ERR(ctx, "out of memory\n");
kmod_module_unref(m);
}
}
fclose(fp);
*list = l;
return 0;
}
/**
* kmod_module_initstate_str:
* @state: the state as returned by kmod_module_get_initstate()
*
* Translate a initstate to a string.
*
* Returns: the string associated to the @state. This string is statically
* allocated, do not free it.
*/
KMOD_EXPORT const char *kmod_module_initstate_str(enum kmod_module_initstate state)
{
switch (state) {
case KMOD_MODULE_BUILTIN:
return "builtin";
case KMOD_MODULE_LIVE:
return "live";
case KMOD_MODULE_COMING:
return "coming";
case KMOD_MODULE_GOING:
return "going";
default:
return NULL;
}
}
/**
* kmod_module_get_initstate:
* @mod: kmod module
*
* Get the initstate of this @mod, as returned by Linux Kernel, by reading
* /sys filesystem.
*
* Returns: < 0 on error or module state if module is found in kernel, valid states are
* KMOD_MODULE_BUILTIN: module is builtin;
* KMOD_MODULE_LIVE: module is live in kernel;
* KMOD_MODULE_COMING: module is being loaded;
* KMOD_MODULE_GOING: module is being unloaded.
*/
KMOD_EXPORT int kmod_module_get_initstate(const struct kmod_module *mod)
{
char path[PATH_MAX], buf[32];
int fd, err, pathlen;
if (mod == NULL)
return -ENOENT;
if (mod->builtin)
return KMOD_MODULE_BUILTIN;
pathlen = snprintf(path, sizeof(path),
"/sys/module/%s/initstate", mod->name);
fd = open(path, O_RDONLY|O_CLOEXEC);
if (fd < 0) {
err = -errno;
DBG(mod->ctx, "could not open '%s': %s\n",
path, strerror(-err));
if (pathlen > (int)sizeof("/initstate") - 1) {
struct stat st;
path[pathlen - (sizeof("/initstate") - 1)] = '\0';
if (stat(path, &st) == 0 && S_ISDIR(st.st_mode))
return KMOD_MODULE_BUILTIN;
}
DBG(mod->ctx, "could not open '%s': %s\n",
path, strerror(-err));
return err;
}
err = read_str_safe(fd, buf, sizeof(buf));
close(fd);
if (err < 0) {
ERR(mod->ctx, "could not read from '%s': %s\n",
path, strerror(-err));
return err;
}
if (streq(buf, "live\n"))
return KMOD_MODULE_LIVE;
else if (streq(buf, "coming\n"))
return KMOD_MODULE_COMING;
else if (streq(buf, "going\n"))
return KMOD_MODULE_GOING;
ERR(mod->ctx, "unknown %s: '%s'\n", path, buf);
return -EINVAL;
}
/**
* kmod_module_get_size:
* @mod: kmod module
*
* Get the size of this kmod module as returned by Linux kernel. If supported,
* the size is read from the coresize attribute in /sys/module. For older
* kernels, this falls back on /proc/modules and searches for the specified
* module to get its size.
*
* Returns: the size of this kmod module.
*/
KMOD_EXPORT long kmod_module_get_size(const struct kmod_module *mod)
{
FILE *fp;
char line[4096];
int lineno = 0;
long size = -ENOENT;
int dfd, cfd;
if (mod == NULL)
return -ENOENT;
/* try to open the module dir in /sys. If this fails, don't
* bother trying to find the size as we know the module isn't
* loaded.
*/
snprintf(line, sizeof(line), "/sys/module/%s", mod->name);
dfd = open(line, O_RDONLY);
if (dfd < 0)
return -errno;
/* available as of linux 3.3.x */
cfd = openat(dfd, "coresize", O_RDONLY|O_CLOEXEC);
if (cfd >= 0) {
if (read_str_long(cfd, &size, 10) < 0)
ERR(mod->ctx, "failed to read coresize from %s\n", line);
close(cfd);
goto done;
}
/* fall back on parsing /proc/modules */
fp = fopen("/proc/modules", "re");
if (fp == NULL) {
int err = -errno;
ERR(mod->ctx,
"could not open /proc/modules: %s\n", strerror(errno));
return err;
}
while (fgets(line, sizeof(line), fp)) {
char *saveptr, *endptr, *tok = strtok_r(line, " \t", &saveptr);
long value;
lineno++;
if (tok == NULL || !streq(tok, mod->name))
continue;
tok = strtok_r(NULL, " \t", &saveptr);
if (tok == NULL) {
ERR(mod->ctx,
"invalid line format at /proc/modules:%d\n", lineno);
break;
}
value = strtol(tok, &endptr, 10);
if (endptr == tok || *endptr != '\0') {
ERR(mod->ctx,
"invalid line format at /proc/modules:%d\n", lineno);
break;
}
size = value;
break;
}
fclose(fp);
done:
close(dfd);
return size;
}
/**
* kmod_module_get_refcnt:
* @mod: kmod module
*
* Get the ref count of this @mod, as returned by Linux Kernel, by reading
* /sys filesystem.
*
* Returns: 0 on success or < 0 on failure.
*/
KMOD_EXPORT int kmod_module_get_refcnt(const struct kmod_module *mod)
{
char path[PATH_MAX];
long refcnt;
int fd, err;
if (mod == NULL)
return -ENOENT;
snprintf(path, sizeof(path), "/sys/module/%s/refcnt", mod->name);
fd = open(path, O_RDONLY|O_CLOEXEC);
if (fd < 0) {
err = -errno;
DBG(mod->ctx, "could not open '%s': %s\n",
path, strerror(errno));
return err;
}
err = read_str_long(fd, &refcnt, 10);
close(fd);
if (err < 0) {
ERR(mod->ctx, "could not read integer from '%s': '%s'\n",
path, strerror(-err));
return err;
}
return (int)refcnt;
}
/**
* kmod_module_get_holders:
* @mod: kmod module
*
* Get a list of kmod modules that are holding this @mod, as returned by Linux
* Kernel. After use, free the @list by calling kmod_module_unref_list().
*
* Returns: a new list of kmod modules on success or NULL on failure.
*/
KMOD_EXPORT struct kmod_list *kmod_module_get_holders(const struct kmod_module *mod)
{
char dname[PATH_MAX];
struct kmod_list *list = NULL;
struct dirent *dent;
DIR *d;
if (mod == NULL || mod->ctx == NULL)
return NULL;
snprintf(dname, sizeof(dname), "/sys/module/%s/holders", mod->name);
d = opendir(dname);
if (d == NULL) {
ERR(mod->ctx, "could not open '%s': %s\n",
dname, strerror(errno));
return NULL;
}
for (dent = readdir(d); dent != NULL; dent = readdir(d)) {
struct kmod_module *holder;
struct kmod_list *l;
int err;
if (dent->d_name[0] == '.') {
if (dent->d_name[1] == '\0' ||
(dent->d_name[1] == '.' && dent->d_name[2] == '\0'))
continue;
}
err = kmod_module_new_from_name(mod->ctx, dent->d_name,
&holder);
if (err < 0) {
ERR(mod->ctx, "could not create module for '%s': %s\n",
dent->d_name, strerror(-err));
goto fail;
}
l = kmod_list_append(list, holder);
if (l != NULL) {
list = l;
} else {
ERR(mod->ctx, "out of memory\n");
kmod_module_unref(holder);
goto fail;
}
}
closedir(d);
return list;
fail:
closedir(d);
kmod_module_unref_list(list);
return NULL;
}
struct kmod_module_section {
unsigned long address;
char name[];
};
static void kmod_module_section_free(struct kmod_module_section *section)
{
free(section);
}
/**
* kmod_module_get_sections:
* @mod: kmod module
*
* Get a list of kmod sections of this @mod, as returned by Linux Kernel. The
* structure contained in this list is internal to libkmod and their fields
* can be obtained by calling kmod_module_section_get_name() and
* kmod_module_section_get_address().
*
* After use, free the @list by calling kmod_module_section_free_list().
*
* Returns: a new list of kmod module sections on success or NULL on failure.
*/
KMOD_EXPORT struct kmod_list *kmod_module_get_sections(const struct kmod_module *mod)
{
char dname[PATH_MAX];
struct kmod_list *list = NULL;
struct dirent *dent;
DIR *d;
int dfd;
if (mod == NULL)
return NULL;
snprintf(dname, sizeof(dname), "/sys/module/%s/sections", mod->name);
d = opendir(dname);
if (d == NULL) {
ERR(mod->ctx, "could not open '%s': %s\n",
dname, strerror(errno));
return NULL;
}
dfd = dirfd(d);
for (dent = readdir(d); dent; dent = readdir(d)) {
struct kmod_module_section *section;
struct kmod_list *l;
unsigned long address;
size_t namesz;
int fd, err;
if (dent->d_name[0] == '.') {
if (dent->d_name[1] == '\0' ||
(dent->d_name[1] == '.' && dent->d_name[2] == '\0'))
continue;
}
fd = openat(dfd, dent->d_name, O_RDONLY|O_CLOEXEC);
if (fd < 0) {
ERR(mod->ctx, "could not open '%s/%s': %m\n",
dname, dent->d_name);
goto fail;
}
err = read_str_ulong(fd, &address, 16);
close(fd);
if (err < 0) {
ERR(mod->ctx, "could not read long from '%s/%s': %m\n",
dname, dent->d_name);
goto fail;
}
namesz = strlen(dent->d_name) + 1;
section = malloc(sizeof(*section) + namesz);
if (section == NULL) {
ERR(mod->ctx, "out of memory\n");
goto fail;
}
section->address = address;
memcpy(section->name, dent->d_name, namesz);
l = kmod_list_append(list, section);
if (l != NULL) {
list = l;
} else {
ERR(mod->ctx, "out of memory\n");
free(section);
goto fail;
}
}
closedir(d);
return list;
fail:
closedir(d);
kmod_module_unref_list(list);
return NULL;
}
/**
* kmod_module_section_get_module_name:
* @entry: a list entry representing a kmod module section
*
* Get the name of a kmod module section.
*
* After use, free the @list by calling kmod_module_section_free_list().
*
* Returns: the name of this kmod module section on success or NULL on
* failure. The string is owned by the section, do not free it.
*/
KMOD_EXPORT const char *kmod_module_section_get_name(const struct kmod_list *entry)
{
struct kmod_module_section *section;
if (entry == NULL)
return NULL;
section = entry->data;
return section->name;
}
/**
* kmod_module_section_get_address:
* @entry: a list entry representing a kmod module section
*
* Get the address of a kmod module section.
*
* After use, free the @list by calling kmod_module_section_free_list().
*
* Returns: the address of this kmod module section on success or ULONG_MAX
* on failure.
*/
KMOD_EXPORT unsigned long kmod_module_section_get_address(const struct kmod_list *entry)
{
struct kmod_module_section *section;
if (entry == NULL)
return (unsigned long)-1;
section = entry->data;
return section->address;
}
/**
* kmod_module_section_free_list:
* @list: kmod module section list
*
* Release the resources taken by @list
*/
KMOD_EXPORT void kmod_module_section_free_list(struct kmod_list *list)
{
while (list) {
kmod_module_section_free(list->data);
list = kmod_list_remove(list);
}
}
static struct kmod_elf *kmod_module_get_elf(const struct kmod_module *mod)
{
if (mod->file == NULL) {
const char *path = kmod_module_get_path(mod);
if (path == NULL) {
errno = ENOENT;
return NULL;
}
((struct kmod_module *)mod)->file = kmod_file_open(mod->ctx,
path);
if (mod->file == NULL)
return NULL;
}
return kmod_file_get_elf(mod->file);
}
struct kmod_module_info {
char *key;
char value[];
};
static struct kmod_module_info *kmod_module_info_new(const char *key, size_t keylen, const char *value, size_t valuelen)
{
struct kmod_module_info *info;
info = malloc(sizeof(struct kmod_module_info) + keylen + valuelen + 2);
if (info == NULL)
return NULL;
info->key = (char *)info + sizeof(struct kmod_module_info)
+ valuelen + 1;
memcpy(info->key, key, keylen);
info->key[keylen] = '\0';
memcpy(info->value, value, valuelen);
info->value[valuelen] = '\0';
return info;
}
static void kmod_module_info_free(struct kmod_module_info *info)
{
free(info);
}
static struct kmod_list *kmod_module_info_append(struct kmod_list **list, const char *key, size_t keylen, const char *value, size_t valuelen)
{
struct kmod_module_info *info;
struct kmod_list *n;
info = kmod_module_info_new(key, keylen, value, valuelen);
if (info == NULL)
return NULL;
n = kmod_list_append(*list, info);
if (n != NULL)
*list = n;
else
kmod_module_info_free(info);
return n;
}
/**
* kmod_module_get_info:
* @mod: kmod module
* @list: where to return list of module information. Use
* kmod_module_info_get_key() and
* kmod_module_info_get_value(). Release this list with
* kmod_module_info_free_list()
*
* Get a list of entries in ELF section ".modinfo", these contain
* alias, license, depends, vermagic and other keys with respective
* values. If the module is signed (CONFIG_MODULE_SIG), information
* about the module signature is included as well: signer,
* sig_key and sig_hashalgo.
*
* After use, free the @list by calling kmod_module_info_free_list().
*
* Returns: 0 on success or < 0 otherwise.
*/
KMOD_EXPORT int kmod_module_get_info(const struct kmod_module *mod, struct kmod_list **list)
{
struct kmod_elf *elf;
char **strings;
int i, count, ret = -ENOMEM;
struct kmod_signature_info sig_info;
if (mod == NULL || list == NULL)
return -ENOENT;
assert(*list == NULL);
elf = kmod_module_get_elf(mod);
if (elf == NULL)
return -errno;
count = kmod_elf_get_strings(elf, ".modinfo", &strings);
if (count < 0)
return count;
for (i = 0; i < count; i++) {
struct kmod_list *n;
const char *key, *value;
size_t keylen, valuelen;
key = strings[i];
value = strchr(key, '=');
if (value == NULL) {
keylen = strlen(key);
valuelen = 0;
value = key;
} else {
keylen = value - key;
value++;
valuelen = strlen(value);
}
n = kmod_module_info_append(list, key, keylen, value, valuelen);
if (n == NULL)
goto list_error;
}
if (kmod_module_signature_info(mod->file, &sig_info)) {
struct kmod_list *n;
char *key_hex;
n = kmod_module_info_append(list, "signer", strlen("signer"),
sig_info.signer, sig_info.signer_len);
if (n == NULL)
goto list_error;
count++;
/* Display the key id as 01:12:DE:AD:BE:EF:... */
key_hex = malloc(sig_info.key_id_len * 3);
if (key_hex == NULL)
goto list_error;
for (i = 0; i < (int)sig_info.key_id_len; i++) {
sprintf(key_hex + i * 3, "%02X",
(unsigned char)sig_info.key_id[i]);
if (i < (int)sig_info.key_id_len - 1)
key_hex[i * 3 + 2] = ':';
}
n = kmod_module_info_append(list, "sig_key", strlen("sig_key"),
key_hex, sig_info.key_id_len * 3 - 1);
free(key_hex);
if (n == NULL)
goto list_error;
count++;
n = kmod_module_info_append(list,
"sig_hashalgo", strlen("sig_hashalgo"),
sig_info.hash_algo, strlen(sig_info.hash_algo));
if (n == NULL)
goto list_error;
count++;
/*
* Omit sig_info.id_type and sig_info.algo for now, as these
* are currently constant.
*/
}
ret = count;
list_error:
if (ret < 0) {
kmod_module_info_free_list(*list);
*list = NULL;
}
free(strings);
return ret;
}
/**
* kmod_module_info_get_key:
* @entry: a list entry representing a kmod module info
*
* Get the key of a kmod module info.
*
* Returns: the key of this kmod module info on success or NULL on
* failure. The string is owned by the info, do not free it.
*/
KMOD_EXPORT const char *kmod_module_info_get_key(const struct kmod_list *entry)
{
struct kmod_module_info *info;
if (entry == NULL)
return NULL;
info = entry->data;
return info->key;
}
/**
* kmod_module_info_get_value:
* @entry: a list entry representing a kmod module info
*
* Get the value of a kmod module info.
*
* Returns: the value of this kmod module info on success or NULL on
* failure. The string is owned by the info, do not free it.
*/
KMOD_EXPORT const char *kmod_module_info_get_value(const struct kmod_list *entry)
{
struct kmod_module_info *info;
if (entry == NULL)
return NULL;
info = entry->data;
return info->value;
}
/**
* kmod_module_info_free_list:
* @list: kmod module info list
*
* Release the resources taken by @list
*/
KMOD_EXPORT void kmod_module_info_free_list(struct kmod_list *list)
{
while (list) {
kmod_module_info_free(list->data);
list = kmod_list_remove(list);
}
}
struct kmod_module_version {
uint64_t crc;
char symbol[];
};
static struct kmod_module_version *kmod_module_versions_new(uint64_t crc, const char *symbol)
{
struct kmod_module_version *mv;
size_t symbollen = strlen(symbol) + 1;
mv = malloc(sizeof(struct kmod_module_version) + symbollen);
if (mv == NULL)
return NULL;
mv->crc = crc;
memcpy(mv->symbol, symbol, symbollen);
return mv;
}
static void kmod_module_version_free(struct kmod_module_version *version)
{
free(version);
}
/**
* kmod_module_get_versions:
* @mod: kmod module
* @list: where to return list of module versions. Use
* kmod_module_version_get_symbol() and
* kmod_module_version_get_crc(). Release this list with
* kmod_module_versions_free_list()
*
* Get a list of entries in ELF section "__versions".
*
* After use, free the @list by calling kmod_module_versions_free_list().
*
* Returns: 0 on success or < 0 otherwise.
*/
KMOD_EXPORT int kmod_module_get_versions(const struct kmod_module *mod, struct kmod_list **list)
{
struct kmod_elf *elf;
struct kmod_modversion *versions;
int i, count, ret = 0;
if (mod == NULL || list == NULL)
return -ENOENT;
assert(*list == NULL);
elf = kmod_module_get_elf(mod);
if (elf == NULL)
return -errno;
count = kmod_elf_get_modversions(elf, &versions);
if (count < 0)
return count;
for (i = 0; i < count; i++) {
struct kmod_module_version *mv;
struct kmod_list *n;
mv = kmod_module_versions_new(versions[i].crc, versions[i].symbol);
if (mv == NULL) {
ret = -errno;
kmod_module_versions_free_list(*list);
*list = NULL;
goto list_error;
}
n = kmod_list_append(*list, mv);
if (n != NULL)
*list = n;
else {
kmod_module_version_free(mv);
kmod_module_versions_free_list(*list);
*list = NULL;
ret = -ENOMEM;
goto list_error;
}
}
ret = count;
list_error:
free(versions);
return ret;
}
/**
* kmod_module_version_get_symbol:
* @entry: a list entry representing a kmod module versions
*
* Get the symbol of a kmod module versions.
*
* Returns: the symbol of this kmod module versions on success or NULL
* on failure. The string is owned by the versions, do not free it.
*/
KMOD_EXPORT const char *kmod_module_version_get_symbol(const struct kmod_list *entry)
{
struct kmod_module_version *version;
if (entry == NULL)
return NULL;
version = entry->data;
return version->symbol;
}
/**
* kmod_module_version_get_crc:
* @entry: a list entry representing a kmod module version
*
* Get the crc of a kmod module version.
*
* Returns: the crc of this kmod module version on success or NULL on
* failure. The string is owned by the version, do not free it.
*/
KMOD_EXPORT uint64_t kmod_module_version_get_crc(const struct kmod_list *entry)
{
struct kmod_module_version *version;
if (entry == NULL)
return 0;
version = entry->data;
return version->crc;
}
/**
* kmod_module_versions_free_list:
* @list: kmod module versions list
*
* Release the resources taken by @list
*/
KMOD_EXPORT void kmod_module_versions_free_list(struct kmod_list *list)
{
while (list) {
kmod_module_version_free(list->data);
list = kmod_list_remove(list);
}
}
struct kmod_module_symbol {
uint64_t crc;
char symbol[];
};
static struct kmod_module_symbol *kmod_module_symbols_new(uint64_t crc, const char *symbol)
{
struct kmod_module_symbol *mv;
size_t symbollen = strlen(symbol) + 1;
mv = malloc(sizeof(struct kmod_module_symbol) + symbollen);
if (mv == NULL)
return NULL;
mv->crc = crc;
memcpy(mv->symbol, symbol, symbollen);
return mv;
}
static void kmod_module_symbol_free(struct kmod_module_symbol *symbol)
{
free(symbol);
}
/**
* kmod_module_get_symbols:
* @mod: kmod module
* @list: where to return list of module symbols. Use
* kmod_module_symbol_get_symbol() and
* kmod_module_symbol_get_crc(). Release this list with
* kmod_module_symbols_free_list()
*
* Get a list of entries in ELF section ".symtab" or "__ksymtab_strings".
*
* After use, free the @list by calling kmod_module_symbols_free_list().
*
* Returns: 0 on success or < 0 otherwise.
*/
KMOD_EXPORT int kmod_module_get_symbols(const struct kmod_module *mod, struct kmod_list **list)
{
struct kmod_elf *elf;
struct kmod_modversion *symbols;
int i, count, ret = 0;
if (mod == NULL || list == NULL)
return -ENOENT;
assert(*list == NULL);
elf = kmod_module_get_elf(mod);
if (elf == NULL)
return -errno;
count = kmod_elf_get_symbols(elf, &symbols);
if (count < 0)
return count;
for (i = 0; i < count; i++) {
struct kmod_module_symbol *mv;
struct kmod_list *n;
mv = kmod_module_symbols_new(symbols[i].crc, symbols[i].symbol);
if (mv == NULL) {
ret = -errno;
kmod_module_symbols_free_list(*list);
*list = NULL;
goto list_error;
}
n = kmod_list_append(*list, mv);
if (n != NULL)
*list = n;
else {
kmod_module_symbol_free(mv);
kmod_module_symbols_free_list(*list);
*list = NULL;
ret = -ENOMEM;
goto list_error;
}
}
ret = count;
list_error:
free(symbols);
return ret;
}
/**
* kmod_module_symbol_get_symbol:
* @entry: a list entry representing a kmod module symbols
*
* Get the symbol of a kmod module symbols.
*
* Returns: the symbol of this kmod module symbols on success or NULL
* on failure. The string is owned by the symbols, do not free it.
*/
KMOD_EXPORT const char *kmod_module_symbol_get_symbol(const struct kmod_list *entry)
{
struct kmod_module_symbol *symbol;
if (entry == NULL)
return NULL;
symbol = entry->data;
return symbol->symbol;
}
/**
* kmod_module_symbol_get_crc:
* @entry: a list entry representing a kmod module symbol
*
* Get the crc of a kmod module symbol.
*
* Returns: the crc of this kmod module symbol on success or NULL on
* failure. The string is owned by the symbol, do not free it.
*/
KMOD_EXPORT uint64_t kmod_module_symbol_get_crc(const struct kmod_list *entry)
{
struct kmod_module_symbol *symbol;
if (entry == NULL)
return 0;
symbol = entry->data;
return symbol->crc;
}
/**
* kmod_module_symbols_free_list:
* @list: kmod module symbols list
*
* Release the resources taken by @list
*/
KMOD_EXPORT void kmod_module_symbols_free_list(struct kmod_list *list)
{
while (list) {
kmod_module_symbol_free(list->data);
list = kmod_list_remove(list);
}
}
struct kmod_module_dependency_symbol {
uint64_t crc;
uint8_t bind;
char symbol[];
};
static struct kmod_module_dependency_symbol *kmod_module_dependency_symbols_new(uint64_t crc, uint8_t bind, const char *symbol)
{
struct kmod_module_dependency_symbol *mv;
size_t symbollen = strlen(symbol) + 1;
mv = malloc(sizeof(struct kmod_module_dependency_symbol) + symbollen);
if (mv == NULL)
return NULL;
mv->crc = crc;
mv->bind = bind;
memcpy(mv->symbol, symbol, symbollen);
return mv;
}
static void kmod_module_dependency_symbol_free(struct kmod_module_dependency_symbol *dependency_symbol)
{
free(dependency_symbol);
}
/**
* kmod_module_get_dependency_symbols:
* @mod: kmod module
* @list: where to return list of module dependency_symbols. Use
* kmod_module_dependency_symbol_get_symbol() and
* kmod_module_dependency_symbol_get_crc(). Release this list with
* kmod_module_dependency_symbols_free_list()
*
* Get a list of entries in ELF section ".symtab" or "__ksymtab_strings".
*
* After use, free the @list by calling
* kmod_module_dependency_symbols_free_list().
*
* Returns: 0 on success or < 0 otherwise.
*/
KMOD_EXPORT int kmod_module_get_dependency_symbols(const struct kmod_module *mod, struct kmod_list **list)
{
struct kmod_elf *elf;
struct kmod_modversion *symbols;
int i, count, ret = 0;
if (mod == NULL || list == NULL)
return -ENOENT;
assert(*list == NULL);
elf = kmod_module_get_elf(mod);
if (elf == NULL)
return -errno;
count = kmod_elf_get_dependency_symbols(elf, &symbols);
if (count < 0)
return count;
for (i = 0; i < count; i++) {
struct kmod_module_dependency_symbol *mv;
struct kmod_list *n;
mv = kmod_module_dependency_symbols_new(symbols[i].crc,
symbols[i].bind,
symbols[i].symbol);
if (mv == NULL) {
ret = -errno;
kmod_module_dependency_symbols_free_list(*list);
*list = NULL;
goto list_error;
}
n = kmod_list_append(*list, mv);
if (n != NULL)
*list = n;
else {
kmod_module_dependency_symbol_free(mv);
kmod_module_dependency_symbols_free_list(*list);
*list = NULL;
ret = -ENOMEM;
goto list_error;
}
}
ret = count;
list_error:
free(symbols);
return ret;
}
/**
* kmod_module_dependency_symbol_get_symbol:
* @entry: a list entry representing a kmod module dependency_symbols
*
* Get the dependency symbol of a kmod module
*
* Returns: the symbol of this kmod module dependency_symbols on success or NULL
* on failure. The string is owned by the dependency_symbols, do not free it.
*/
KMOD_EXPORT const char *kmod_module_dependency_symbol_get_symbol(const struct kmod_list *entry)
{
struct kmod_module_dependency_symbol *dependency_symbol;
if (entry == NULL)
return NULL;
dependency_symbol = entry->data;
return dependency_symbol->symbol;
}
/**
* kmod_module_dependency_symbol_get_crc:
* @entry: a list entry representing a kmod module dependency_symbol
*
* Get the crc of a kmod module dependency_symbol.
*
* Returns: the crc of this kmod module dependency_symbol on success or NULL on
* failure. The string is owned by the dependency_symbol, do not free it.
*/
KMOD_EXPORT uint64_t kmod_module_dependency_symbol_get_crc(const struct kmod_list *entry)
{
struct kmod_module_dependency_symbol *dependency_symbol;
if (entry == NULL)
return 0;
dependency_symbol = entry->data;
return dependency_symbol->crc;
}
/**
* kmod_module_dependency_symbol_get_bind:
* @entry: a list entry representing a kmod module dependency_symbol
*
* Get the bind type of a kmod module dependency_symbol.
*
* Returns: the bind of this kmod module dependency_symbol on success
* or < 0 on failure.
*/
KMOD_EXPORT int kmod_module_dependency_symbol_get_bind(const struct kmod_list *entry)
{
struct kmod_module_dependency_symbol *dependency_symbol;
if (entry == NULL)
return 0;
dependency_symbol = entry->data;
return dependency_symbol->bind;
}
/**
* kmod_module_dependency_symbols_free_list:
* @list: kmod module dependency_symbols list
*
* Release the resources taken by @list
*/
KMOD_EXPORT void kmod_module_dependency_symbols_free_list(struct kmod_list *list)
{
while (list) {
kmod_module_dependency_symbol_free(list->data);
list = kmod_list_remove(list);
}
}