blob: a5c6d114eb247f26dccc04405b2c6200618e7f27 [file] [log] [blame]
/*
* libkmod - interface to kernel module operations
*
* Copyright (C) 2011-2012 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 <stdio.h>
#include <stdlib.h>
#include <stddef.h>
#include <stdarg.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <ctype.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <dirent.h>
#include "libkmod.h"
#include "libkmod-private.h"
struct kmod_alias {
char *name;
char modname[];
};
struct kmod_options {
char *options;
char modname[];
};
struct kmod_command {
char *command;
char modname[];
};
struct kmod_softdep {
char *name;
const char **pre;
const char **post;
unsigned int n_pre;
unsigned int n_post;
};
const char *kmod_blacklist_get_modname(const struct kmod_list *l)
{
return l->data;
}
const char *kmod_alias_get_name(const struct kmod_list *l) {
const struct kmod_alias *alias = l->data;
return alias->name;
}
const char *kmod_alias_get_modname(const struct kmod_list *l) {
const struct kmod_alias *alias = l->data;
return alias->modname;
}
const char *kmod_option_get_options(const struct kmod_list *l) {
const struct kmod_options *alias = l->data;
return alias->options;
}
const char *kmod_option_get_modname(const struct kmod_list *l) {
const struct kmod_options *alias = l->data;
return alias->modname;
}
const char *kmod_command_get_command(const struct kmod_list *l) {
const struct kmod_command *alias = l->data;
return alias->command;
}
const char *kmod_command_get_modname(const struct kmod_list *l) {
const struct kmod_command *alias = l->data;
return alias->modname;
}
const char *kmod_softdep_get_name(const struct kmod_list *l) {
const struct kmod_softdep *dep = l->data;
return dep->name;
}
const char * const *kmod_softdep_get_pre(const struct kmod_list *l, unsigned int *count) {
const struct kmod_softdep *dep = l->data;
*count = dep->n_pre;
return dep->pre;
}
const char * const *kmod_softdep_get_post(const struct kmod_list *l, unsigned int *count) {
const struct kmod_softdep *dep = l->data;
*count = dep->n_post;
return dep->post;
}
static int kmod_config_add_command(struct kmod_config *config,
const char *modname,
const char *command,
const char *command_name,
struct kmod_list **list)
{
struct kmod_command *cmd;
struct kmod_list *l;
size_t modnamelen = strlen(modname) + 1;
size_t commandlen = strlen(command) + 1;
DBG(config->ctx, "modname='%s' cmd='%s %s'\n", modname, command_name,
command);
cmd = malloc(sizeof(*cmd) + modnamelen + commandlen);
if (cmd == NULL)
goto oom_error_init;
cmd->command = sizeof(*cmd) + modnamelen + (char *)cmd;
memcpy(cmd->modname, modname, modnamelen);
memcpy(cmd->command, command, commandlen);
l = kmod_list_append(*list, cmd);
if (l == NULL)
goto oom_error;
*list = l;
return 0;
oom_error:
free(cmd);
oom_error_init:
ERR(config->ctx, "out-of-memory\n");
return -ENOMEM;
}
static void kmod_config_free_command(struct kmod_config *config,
struct kmod_list *l,
struct kmod_list **list)
{
struct kmod_command *cmd = l->data;
free(cmd);
*list = kmod_list_remove(l);
}
static int kmod_config_add_options(struct kmod_config *config,
const char *modname, const char *options)
{
struct kmod_options *opt;
struct kmod_list *list;
size_t modnamelen = strlen(modname) + 1;
size_t optionslen = strlen(options) + 1;
DBG(config->ctx, "modname='%s' options='%s'\n", modname, options);
opt = malloc(sizeof(*opt) + modnamelen + optionslen);
if (opt == NULL)
goto oom_error_init;
opt->options = sizeof(*opt) + modnamelen + (char *)opt;
memcpy(opt->modname, modname, modnamelen);
memcpy(opt->options, options, optionslen);
strchr_replace(opt->options, '\t', ' ');
list = kmod_list_append(config->options, opt);
if (list == NULL)
goto oom_error;
config->options = list;
return 0;
oom_error:
free(opt);
oom_error_init:
ERR(config->ctx, "out-of-memory\n");
return -ENOMEM;
}
static void kmod_config_free_options(struct kmod_config *config,
struct kmod_list *l)
{
struct kmod_options *opt = l->data;
free(opt);
config->options = kmod_list_remove(l);
}
static int kmod_config_add_alias(struct kmod_config *config,
const char *name, const char *modname)
{
struct kmod_alias *alias;
struct kmod_list *list;
size_t namelen = strlen(name) + 1, modnamelen = strlen(modname) + 1;
DBG(config->ctx, "name=%s modname=%s\n", name, modname);
alias = malloc(sizeof(*alias) + namelen + modnamelen);
if (!alias)
goto oom_error_init;
alias->name = sizeof(*alias) + modnamelen + (char *)alias;
memcpy(alias->modname, modname, modnamelen);
memcpy(alias->name, name, namelen);
list = kmod_list_append(config->aliases, alias);
if (!list)
goto oom_error;
config->aliases = list;
return 0;
oom_error:
free(alias);
oom_error_init:
ERR(config->ctx, "out-of-memory name=%s modname=%s\n", name, modname);
return -ENOMEM;
}
static void kmod_config_free_alias(struct kmod_config *config,
struct kmod_list *l)
{
struct kmod_alias *alias = l->data;
free(alias);
config->aliases = kmod_list_remove(l);
}
static int kmod_config_add_blacklist(struct kmod_config *config,
const char *modname)
{
char *p;
struct kmod_list *list;
DBG(config->ctx, "modname=%s\n", modname);
p = strdup(modname);
if (!p)
goto oom_error_init;
list = kmod_list_append(config->blacklists, p);
if (!list)
goto oom_error;
config->blacklists = list;
return 0;
oom_error:
free(p);
oom_error_init:
ERR(config->ctx, "out-of-memory modname=%s\n", modname);
return -ENOMEM;
}
static void kmod_config_free_blacklist(struct kmod_config *config,
struct kmod_list *l)
{
free(l->data);
config->blacklists = kmod_list_remove(l);
}
static int kmod_config_add_softdep(struct kmod_config *config,
const char *modname,
const char *line)
{
struct kmod_list *list;
struct kmod_softdep *dep;
const char *s, *p;
char *itr;
unsigned int n_pre = 0, n_post = 0;
size_t modnamelen = strlen(modname) + 1;
size_t buflen = 0;
bool was_space = false;
enum { S_NONE, S_PRE, S_POST } mode = S_NONE;
DBG(config->ctx, "modname=%s\n", modname);
/* analyze and count */
for (p = s = line; ; s++) {
size_t plen;
if (*s != '\0') {
if (!isspace(*s)) {
was_space = false;
continue;
}
if (was_space) {
p = s + 1;
continue;
}
was_space = true;
if (p >= s)
continue;
}
plen = s - p;
if (plen == sizeof("pre:") - 1 &&
memcmp(p, "pre:", sizeof("pre:") - 1) == 0)
mode = S_PRE;
else if (plen == sizeof("post:") - 1 &&
memcmp(p, "post:", sizeof("post:") - 1) == 0)
mode = S_POST;
else if (*s != '\0' || (*s == '\0' && !was_space)) {
if (mode == S_PRE) {
buflen += plen + 1;
n_pre++;
} else if (mode == S_POST) {
buflen += plen + 1;
n_post++;
}
}
p = s + 1;
if (*s == '\0')
break;
}
DBG(config->ctx, "%u pre, %u post\n", n_pre, n_post);
dep = malloc(sizeof(struct kmod_softdep) + modnamelen +
n_pre * sizeof(const char *) +
n_post * sizeof(const char *) +
buflen);
if (dep == NULL) {
ERR(config->ctx, "out-of-memory modname=%s\n", modname);
return -ENOMEM;
}
dep->n_pre = n_pre;
dep->n_post = n_post;
dep->pre = (const char **)((char *)dep + sizeof(struct kmod_softdep));
dep->post = dep->pre + n_pre;
dep->name = (char *)(dep->post + n_post);
memcpy(dep->name, modname, modnamelen);
/* copy strings */
itr = dep->name + modnamelen;
n_pre = 0;
n_post = 0;
mode = S_NONE;
for (p = s = line; ; s++) {
size_t plen;
if (*s != '\0') {
if (!isspace(*s)) {
was_space = false;
continue;
}
if (was_space) {
p = s + 1;
continue;
}
was_space = true;
if (p >= s)
continue;
}
plen = s - p;
if (plen == sizeof("pre:") - 1 &&
memcmp(p, "pre:", sizeof("pre:") - 1) == 0)
mode = S_PRE;
else if (plen == sizeof("post:") - 1 &&
memcmp(p, "post:", sizeof("post:") - 1) == 0)
mode = S_POST;
else if (*s != '\0' || (*s == '\0' && !was_space)) {
if (mode == S_PRE) {
dep->pre[n_pre] = itr;
memcpy(itr, p, plen);
itr[plen] = '\0';
itr += plen + 1;
n_pre++;
} else if (mode == S_POST) {
dep->post[n_post] = itr;
memcpy(itr, p, plen);
itr[plen] = '\0';
itr += plen + 1;
n_post++;
}
}
p = s + 1;
if (*s == '\0')
break;
}
list = kmod_list_append(config->softdeps, dep);
if (list == NULL) {
free(dep);
return -ENOMEM;
}
config->softdeps = list;
return 0;
}
static void kmod_config_free_softdep(struct kmod_config *config,
struct kmod_list *l)
{
free(l->data);
config->softdeps = kmod_list_remove(l);
}
static void kcmdline_parse_result(struct kmod_config *config, char *modname,
char *param, char *value)
{
if (modname == NULL || param == NULL || value == NULL)
return;
DBG(config->ctx, "%s %s\n", modname, param);
if (streq(modname, "modprobe") && !strncmp(param, "blacklist=", 10)) {
for (;;) {
char *t = strsep(&value, ",");
if (t == NULL)
break;
kmod_config_add_blacklist(config, t);
}
} else {
kmod_config_add_options(config,
underscores(config->ctx, modname), param);
}
}
static int kmod_config_parse_kcmdline(struct kmod_config *config)
{
char buf[KCMD_LINE_SIZE];
int fd, err;
char *p, *modname, *param = NULL, *value = NULL;
fd = open("/proc/cmdline", O_RDONLY|O_CLOEXEC);
if (fd < 0) {
err = -errno;
DBG(config->ctx, "could not open '/proc/cmdline' for reading: %m\n");
return err;
}
err = read_str_safe(fd, buf, sizeof(buf));
close(fd);
if (err < 0) {
ERR(config->ctx, "could not read from '/proc/cmdline': %s\n",
strerror(-err));
return err;
}
for (p = buf, modname = buf; *p != '\0' && *p != '\n'; p++) {
switch (*p) {
case ' ':
*p = '\0';
kcmdline_parse_result(config, modname, param, value);
param = value = NULL;
modname = p + 1;
break;
case '.':
*p = '\0';
param = p + 1;
break;
case '=':
if (param != NULL)
value = p + 1;
break;
}
}
*p = '\0';
kcmdline_parse_result(config, modname, param, value);
return 0;
}
/*
* Take an fd and own it. It will be closed on return. filename is used only
* for debug messages
*/
static int kmod_config_parse(struct kmod_config *config, int fd,
const char *filename)
{
struct kmod_ctx *ctx = config->ctx;
char *line;
FILE *fp;
unsigned int linenum = 0;
int err;
fp = fdopen(fd, "r");
if (fp == NULL) {
err = -errno;
ERR(config->ctx, "fd %d: %m", fd);
close(fd);
return err;
}
while ((line = getline_wrapped(fp, &linenum)) != NULL) {
char *cmd, *saveptr;
if (line[0] == '\0' || line[0] == '#')
goto done_next;
cmd = strtok_r(line, "\t ", &saveptr);
if (cmd == NULL)
goto done_next;
if (streq(cmd, "alias")) {
char *alias = strtok_r(NULL, "\t ", &saveptr);
char *modname = strtok_r(NULL, "\t ", &saveptr);
if (alias == NULL || modname == NULL)
goto syntax_error;
kmod_config_add_alias(config,
underscores(ctx, alias),
underscores(ctx, modname));
} else if (streq(cmd, "blacklist")) {
char *modname = strtok_r(NULL, "\t ", &saveptr);
if (modname == NULL)
goto syntax_error;
kmod_config_add_blacklist(config,
underscores(ctx, modname));
} else if (streq(cmd, "options")) {
char *modname = strtok_r(NULL, "\t ", &saveptr);
char *options = strtok_r(NULL, "\0", &saveptr);
if (modname == NULL || options == NULL)
goto syntax_error;
kmod_config_add_options(config,
underscores(ctx, modname),
options);
} else if (streq(cmd, "install")) {
char *modname = strtok_r(NULL, "\t ", &saveptr);
char *installcmd = strtok_r(NULL, "\0", &saveptr);
if (modname == NULL || installcmd == NULL)
goto syntax_error;
kmod_config_add_command(config,
underscores(ctx, modname),
installcmd,
cmd, &config->install_commands);
} else if (streq(cmd, "remove")) {
char *modname = strtok_r(NULL, "\t ", &saveptr);
char *removecmd = strtok_r(NULL, "\0", &saveptr);
if (modname == NULL || removecmd == NULL)
goto syntax_error;
kmod_config_add_command(config,
underscores(ctx, modname),
removecmd,
cmd, &config->remove_commands);
} else if (streq(cmd, "softdep")) {
char *modname = strtok_r(NULL, "\t ", &saveptr);
char *softdeps = strtok_r(NULL, "\0", &saveptr);
if (modname == NULL || softdeps == NULL)
goto syntax_error;
kmod_config_add_softdep(config,
underscores(ctx, modname),
softdeps);
} else if (streq(cmd, "include")
|| streq(cmd, "config")) {
ERR(ctx, "%s: command %s is deprecated and not parsed anymore\n",
filename, cmd);
} else {
syntax_error:
ERR(ctx, "%s line %u: ignoring bad line starting with '%s'\n",
filename, linenum, cmd);
}
done_next:
free(line);
}
fclose(fp);
return 0;
}
void kmod_config_free(struct kmod_config *config)
{
while (config->aliases)
kmod_config_free_alias(config, config->aliases);
while (config->blacklists)
kmod_config_free_blacklist(config, config->blacklists);
while (config->options)
kmod_config_free_options(config, config->options);
while (config->install_commands) {
kmod_config_free_command(config, config->install_commands,
&config->install_commands);
}
while (config->remove_commands) {
kmod_config_free_command(config, config->remove_commands,
&config->remove_commands);
}
while (config->softdeps)
kmod_config_free_softdep(config, config->softdeps);
for (; config->paths != NULL;
config->paths = kmod_list_remove(config->paths))
free(config->paths->data);
free(config);
}
static bool conf_files_filter_out(struct kmod_ctx *ctx, DIR *d,
const char *path, const char *fn)
{
size_t len = strlen(fn);
struct stat st;
if (fn[0] == '.')
return true;
if (len < 6 || (!streq(&fn[len - 5], ".conf")
&& !streq(&fn[len - 6], ".alias")))
return true;
fstatat(dirfd(d), fn, &st, 0);
if (S_ISDIR(st.st_mode)) {
ERR(ctx, "Directories inside directories are not supported: "
"%s/%s\n", path, fn);
return true;
}
return false;
}
struct conf_file {
const char *path;
bool is_single;
char name[];
};
static int conf_files_insert_sorted(struct kmod_ctx *ctx,
struct kmod_list **list,
const char *path, const char *name)
{
struct kmod_list *lpos, *tmp;
struct conf_file *cf;
size_t namelen;
int cmp = -1;
bool is_single = false;
if (name == NULL) {
name = basename(path);
is_single = true;
}
kmod_list_foreach(lpos, *list) {
cf = lpos->data;
if ((cmp = strcmp(name, cf->name)) <= 0)
break;
}
if (cmp == 0) {
DBG(ctx, "Ignoring duplicate config file: %s/%s\n", path,
name);
return -EEXIST;
}
namelen = strlen(name);
cf = malloc(sizeof(*cf) + namelen + 1);
if (cf == NULL)
return -ENOMEM;
memcpy(cf->name, name, namelen + 1);
cf->path = path;
cf->is_single = is_single;
if (lpos == NULL)
tmp = kmod_list_append(*list, cf);
else if (lpos == *list)
tmp = kmod_list_prepend(*list, cf);
else
tmp = kmod_list_insert_before(lpos, cf);
if (tmp == NULL) {
free(cf);
return -ENOMEM;
}
if (lpos == NULL || lpos == *list)
*list = tmp;
return 0;
}
/*
* Insert configuration files in @list, ignoring duplicates
*/
static int conf_files_list(struct kmod_ctx *ctx, struct kmod_list **list,
const char *path,
unsigned long long *path_stamp)
{
DIR *d;
int err;
struct stat st;
if (stat(path, &st) != 0) {
err = -errno;
DBG(ctx, "could not stat '%s': %m\n", path);
return err;
}
*path_stamp = ts_usec(&st.st_mtim);
if (S_ISREG(st.st_mode)) {
conf_files_insert_sorted(ctx, list, path, NULL);
return 0;
} if (!S_ISDIR(st.st_mode)) {
ERR(ctx, "unsupported file mode %s: %#x\n",
path, st.st_mode);
return -EINVAL;
}
d = opendir(path);
if (d == NULL) {
ERR(ctx, "%m\n");
return -EINVAL;
}
for (;;) {
struct dirent ent, *entp;
err = readdir_r(d, &ent, &entp);
if (err != 0) {
ERR(ctx, "reading entry %s\n", strerror(-err));
goto fail_read;
}
if (entp == NULL)
break;
if (conf_files_filter_out(ctx, d, path, entp->d_name))
continue;
conf_files_insert_sorted(ctx, list, path, entp->d_name);
}
closedir(d);
return 0;
fail_read:
closedir(d);
return err;
}
int kmod_config_new(struct kmod_ctx *ctx, struct kmod_config **p_config,
const char * const *config_paths)
{
struct kmod_config *config;
struct kmod_list *list = NULL;
struct kmod_list *path_list = NULL;
size_t i;
for (i = 0; config_paths[i] != NULL; i++) {
const char *path = config_paths[i];
unsigned long long path_stamp = 0;
size_t pathlen;
struct kmod_list *tmp;
struct kmod_config_path *cf;
if (conf_files_list(ctx, &list, path, &path_stamp) < 0)
continue;
pathlen = strlen(path) + 1;
cf = malloc(sizeof(*cf) + pathlen);
if (cf == NULL)
goto oom;
cf->stamp = path_stamp;
memcpy(cf->path, path, pathlen);
tmp = kmod_list_append(path_list, cf);
if (tmp == NULL)
goto oom;
path_list = tmp;
}
*p_config = config = calloc(1, sizeof(struct kmod_config));
if (config == NULL)
goto oom;
config->paths = path_list;
config->ctx = ctx;
for (; list != NULL; list = kmod_list_remove(list)) {
char fn[PATH_MAX];
struct conf_file *cf = list->data;
int fd;
if (cf->is_single)
strcpy(fn, cf->path);
else
snprintf(fn, sizeof(fn),"%s/%s", cf->path,
cf->name);
fd = open(fn, O_RDONLY|O_CLOEXEC);
DBG(ctx, "parsing file '%s' fd=%d\n", fn, fd);
if (fd >= 0)
kmod_config_parse(config, fd, fn);
free(cf);
}
kmod_config_parse_kcmdline(config);
return 0;
oom:
for (; list != NULL; list = kmod_list_remove(list))
free(list->data);
for (; path_list != NULL; path_list = kmod_list_remove(path_list))
free(path_list->data);
return -ENOMEM;
}