/*
* Copyright (C) 2012-2013 ProFUSION embedded systems
* Copyright (C) 2012-2013 Lucas De Marchi <lucas.de.marchi@gmail.com>
*
* This program 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 program 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, see <http://www.gnu.org/licenses/>.
*/
#ifndef HAVE_FINIT_MODULE
#define HAVE_FINIT_MODULE 1
#endif
#include <assert.h>
#include <dirent.h>
#include <dlfcn.h>
#include <elf.h>
#include <errno.h>
#include <fcntl.h>
#include <limits.h>
#include <stdarg.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <sys/syscall.h>
#include <sys/types.h>
#include <sys/utsname.h>
#include <shared/util.h>
/* kmod_elf_get_section() is not exported, we need the private header */
#include <libkmod/libkmod-internal.h>
/* FIXME: hack, change name so we don't clash */
#undef ERR
#include "testsuite.h"
#include "stripped-module.h"
struct mod {
struct mod *next;
int ret;
int errcode;
char name[];
};
static struct mod *modules;
static bool need_init = true;
static struct kmod_ctx *ctx;
static void parse_retcodes(struct mod *_modules, const char *s)
{
const char *p;
if (s == NULL)
return;
for (p = s;;) {
struct mod *mod;
const char *modname;
char *end;
size_t modnamelen;
int ret, errcode;
long l;
modname = p;
if (modname == NULL || modname[0] == '\0')
break;
modnamelen = strcspn(s, ":");
if (modname[modnamelen] != ':')
break;
p = modname + modnamelen + 1;
if (p == NULL)
break;
l = strtol(p, &end, 0);
if (end == p || *end != ':')
break;
ret = (int) l;
p = end + 1;
l = strtol(p, &end, 0);
if (*end == ':')
p = end + 1;
else if (*end != '\0')
break;
errcode = (int) l;
mod = malloc(sizeof(*mod) + modnamelen + 1);
if (mod == NULL)
break;
memcpy(mod->name, modname, modnamelen);
mod->name[modnamelen] = '\0';
mod->ret = ret;
mod->errcode = errcode;
mod->next = _modules;
_modules = mod;
}
}
static int write_one_line_file(const char *fn, const char *line, int len)
{
FILE *f;
int r;
assert(fn);
assert(line);
f = fopen(fn, "we");
if (!f)
return -errno;
errno = 0;
if (fputs(line, f) < 0) {
r = -errno;
goto finish;
}
fflush(f);
if (ferror(f)) {
if (errno != 0)
r = -errno;
else
r = -EIO;
} else
r = 0;
finish:
fclose(f);
return r;
}
static int create_sysfs_files(const char *modname)
{
char buf[PATH_MAX];
const char *sysfsmod = "/sys/module/";
int len = strlen(sysfsmod);
memcpy(buf, sysfsmod, len);
strcpy(buf + len, modname);
len += strlen(modname);
assert(mkdir_p(buf, len, 0755) >= 0);
strcpy(buf + len, "/initstate");
return write_one_line_file(buf, "live\n", strlen("live\n"));
}
static struct mod *find_module(struct mod *_modules, const char *modname)
{
struct mod *mod;
for (mod = _modules; mod != NULL; mod = mod->next) {
if (streq(mod->name, modname))
return mod;
}
return NULL;
}
static void init_retcodes(void)
{
const char *s;
if (!need_init)
return;
need_init = false;
s = getenv(S_TC_INIT_MODULE_RETCODES);
if (s == NULL) {
fprintf(stderr, "TRAP init_module(): missing export %s?\n",
S_TC_INIT_MODULE_RETCODES);
}
ctx = kmod_new(NULL, NULL);
parse_retcodes(modules, s);
}
static inline bool module_is_inkernel(const char *modname)
{
struct kmod_module *mod;
int state;
bool ret;
if (kmod_module_new_from_name(ctx, modname, &mod) < 0)
return false;
state = kmod_module_get_initstate(mod);
if (state == KMOD_MODULE_LIVE ||
state == KMOD_MODULE_BUILTIN)
ret = true;
else
ret = false;
kmod_module_unref(mod);
return ret;
}
static uint8_t elf_identify(void *mem)
{
uint8_t *p = mem;
return p[EI_CLASS];
}
TS_EXPORT long init_module(void *mem, unsigned long len, const char *args);
/*
* Default behavior is to try to mimic init_module behavior inside the kernel.
* If it is a simple test that you know the error code, set the return code
* in TESTSUITE_INIT_MODULE_RETCODES env var instead.
*
* The exception is when the module name is not find in the memory passed.
* This is because we want to be able to pass dummy modules (and not real
* ones) and it still work.
*/
long init_module(void *mem, unsigned long len, const char *args)
{
const char *modname;
struct kmod_elf *elf;
struct mod *mod;
const void *buf;
uint64_t bufsize;
int err;
uint8_t class;
off_t offset;
init_retcodes();
elf = kmod_elf_new(mem, len);
if (elf == NULL)
return 0;
err = kmod_elf_get_section(elf, ".gnu.linkonce.this_module", &buf,
&bufsize);
kmod_elf_unref(elf);
/* We couldn't parse the ELF file. Just exit as if it was successful */
if (err < 0)
return 0;
/* We need to open both 32 and 64 bits module - hack! */
class = elf_identify(mem);
if (class == ELFCLASS64)
offset = MODULE_NAME_OFFSET_64;
else
offset = MODULE_NAME_OFFSET_32;
modname = (char *)buf + offset;
mod = find_module(modules, modname);
if (mod != NULL) {
errno = mod->errcode;
err = mod->ret;
} else if (module_is_inkernel(modname)) {
err = -1;
errno = EEXIST;
} else
err = 0;
if (err == 0)
create_sysfs_files(modname);
return err;
}
static int check_kernel_version(int major, int minor)
{
struct utsname u;
const char *p;
int maj = 0, min = 0;
if (uname(&u) < 0)
return false;
for (p = u.release; *p >= '0' && *p <= '9'; p++)
maj = maj * 10 + *p - '0';
if (*p == '.')
for (p++; *p >= '0' && *p <= '9'; p++)
min = min * 10 + *p - '0';
if (maj > major || (maj == major && min >= minor))
return true;
return false;
}
TS_EXPORT int finit_module(const int fd, const char *args, const int flags);
int finit_module(const int fd, const char *args, const int flags)
{
int err;
void *mem;
unsigned long len;
struct stat st;
if (!check_kernel_version(3, 8)) {
errno = ENOSYS;
return -1;
}
if (fstat(fd, &st) < 0)
return -1;
len = st.st_size;
mem = mmap(NULL, len, PROT_READ, MAP_PRIVATE, fd, 0);
if (mem == MAP_FAILED)
return -1;
err = init_module(mem, len, args);
munmap(mem, len);
return err;
}
TS_EXPORT long int syscall(long int __sysno, ...)
{
va_list ap;
long ret;
if (__sysno == -1) {
errno = ENOSYS;
return -1;
}
if (__sysno == __NR_finit_module) {
const char *args;
int flags;
int fd;
va_start(ap, __sysno);
fd = va_arg(ap, int);
args = va_arg(ap, const char *);
flags = va_arg(ap, int);
ret = finit_module(fd, args, flags);
va_end(ap);
return ret;
}
if (__sysno == __NR_gettid) {
static void *nextlib = NULL;
static long (*nextlib_syscall)(long number, ...);
if (nextlib_syscall == NULL) {
#ifdef RTLD_NEXT
nextlib = RTLD_NEXT;
#else
nextlib = dlopen("libc.so.6", RTLD_LAZY);
#endif
nextlib_syscall = dlsym(nextlib, "syscall");
if (nextlib_syscall == NULL) {
fprintf(stderr, "FIXME FIXME FIXME: could not load syscall symbol: %s\n",
dlerror());
abort();
}
}
return nextlib_syscall(__NR_gettid);
}
/*
* FIXME: no way to call the libc function due since this is a
* variadic argument function and we don't have a vsyscall() variant
* this may fail if a library or process is trying to call syscall()
* directly, for example to implement gettid().
*/
fprintf(stderr, "FIXME FIXME FIXME: could not wrap call to syscall(%ld), this should not happen\n",
__sysno);
abort();
}
/* the test is going away anyway, but lets keep valgrind happy */
void free_resources(void) __attribute__((destructor));
void free_resources(void)
{
while (modules) {
struct mod *mod = modules->next;
free(modules);
modules = mod;
}
if (ctx)
kmod_unref(ctx);
}