wasm-micro-runtime/core/shared/utils/bh_common.c
liang.he@intel.com d3a2cdd8f7 Use execve() to replace system() and rename
- Direct Execution: execve() directly executes a program, bypassing the shell.
  This avoids vulnerabilities like shell injection, which can occur with
  system() if user input is not properly sanitized.
- Controlled Environment: With execve(), you can explicitly specify the
  environment variables for the new process, providing better control over
  the execution context.
- No Shell Overhead: execve() does not invoke a shell, reducing the risk
  of unintended behavior caused by shell features or configurations.
- Predictable Behavior: execve() only executes the specified program, whereas
  system() relies on the shell, which may interpret commands differently
  based on the shell's configuration or environment.
2025-04-29 05:31:44 +00:00

242 lines
5.0 KiB
C

/*
* Copyright (C) 2019 Intel Corporation. All rights reserved.
* SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
*/
#include "bh_common.h"
static char *
align_ptr(char *src, unsigned int b)
{
uintptr_t v = (uintptr_t)src;
uintptr_t m = b - 1;
return (char *)((v + m) & ~m);
}
/*
Memory copy, with word alignment
*/
int
b_memcpy_wa(void *s1, unsigned int s1max, const void *s2, unsigned int n)
{
char *dest = (char *)s1;
char *src = (char *)s2;
char *pa = align_ptr(src, 4);
char *pb = align_ptr((src + n), 4);
unsigned int buff;
const char *p_byte_read;
unsigned int *p;
char *ps;
if (n == 0) {
return 0;
}
if (pa > src) {
pa -= 4;
}
for (p = (unsigned int *)pa; p < (unsigned int *)pb; p++) {
buff = *(p);
p_byte_read = ((char *)&buff);
/* read leading word */
if ((char *)p <= src) {
for (ps = src; ps < ((char *)p + 4); ps++) {
if (ps >= src + n) {
break;
}
p_byte_read = ((char *)&buff) + (ps - (char *)p);
*dest++ = *p_byte_read;
}
}
/* read trailing word */
else if ((char *)p >= pb - 4) {
for (ps = (char *)p; ps < src + n; ps++) {
*dest++ = *p_byte_read++;
}
}
/* read meaning word(s) */
else {
if ((char *)p + 4 >= src + n) {
for (ps = (char *)p; ps < src + n; ps++) {
*dest++ = *p_byte_read++;
}
}
else {
*(unsigned int *)dest = buff;
dest += 4;
}
}
}
return 0;
}
int
b_memcpy_s(void *s1, unsigned int s1max, const void *s2, unsigned int n)
{
char *dest = (char *)s1;
char *src = (char *)s2;
if (n == 0) {
return 0;
}
if (s1 == NULL) {
return -1;
}
if (s2 == NULL || n > s1max) {
memset(dest, 0, s1max);
return -1;
}
memcpy(dest, src, n);
return 0;
}
int
b_memmove_s(void *s1, unsigned int s1max, const void *s2, unsigned int n)
{
char *dest = (char *)s1;
char *src = (char *)s2;
if (n == 0) {
return 0;
}
if (s1 == NULL) {
return -1;
}
if (s2 == NULL || n > s1max) {
memset(dest, 0, s1max);
return -1;
}
memmove(dest, src, n);
return 0;
}
int
b_strcat_s(char *s1, unsigned int s1max, const char *s2)
{
if (NULL == s1 || NULL == s2 || s1max < (strlen(s1) + strlen(s2) + 1)) {
return -1;
}
memcpy(s1 + strlen(s1), s2, strlen(s2) + 1);
return 0;
}
int
b_strcpy_s(char *s1, unsigned int s1max, const char *s2)
{
if (NULL == s1 || NULL == s2 || s1max < (strlen(s2) + 1)) {
return -1;
}
memcpy(s1, s2, strlen(s2) + 1);
return 0;
}
char *
bh_strdup(const char *s)
{
uint32 size;
char *s1 = NULL;
if (s) {
size = (uint32)(strlen(s) + 1);
if ((s1 = BH_MALLOC(size)))
bh_memcpy_s(s1, size, s, size);
}
return s1;
}
char *
wa_strdup(const char *s)
{
uint32 size;
char *s1 = NULL;
if (s) {
size = (uint32)(strlen(s) + 1);
if ((s1 = WA_MALLOC(size)))
bh_memcpy_s(s1, size, s, size);
}
return s1;
}
#if WASM_ENABLE_WAMR_COMPILER != 0 || WASM_ENABLE_JIT != 0
/* need to make sure that The `argv[]` must be terminated by a NULL pointer. */
int
bh_execve(const char *pathname, char *const argv[], int argc)
{
int ret;
/* no environment variables */
char *const envp[] = { NULL };
if (pathname == NULL) {
return -1;
}
if (argc > 0) {
if (argv == NULL) {
return -1;
}
/* The `argv[]` must be terminated by a NULL pointer. */
if (argv[argc - 1] != NULL) {
return -1;
}
}
#if !(defined(_WIN32) || defined(_WIN32_))
ret = execve(pathname, argv, envp);
#ifndef NDEBUG
if (ret == -1) {
LOG_WARNING("execute \"%s\" failed because of \"%s\"", pathname,
strerror(errno));
}
#endif
#else
ret = _execve(pathname, argv, envp);
#endif
return ret;
}
#if defined(_WIN32) || defined(_WIN32_)
errno_t
_mktemp_s(char *nameTemplate, size_t sizeInChars);
#endif
bool
bh_mkstemp(char *file_name, size_t name_len)
{
int fd;
#if !(defined(_WIN32) || defined(_WIN32_))
(void)name_len;
/* On Linux, it generates a unique temporary filename from template, creates
* and opens the file, and returns an open file descriptor for the file. */
if ((fd = mkstemp(file_name)) <= 0) {
goto fail;
}
/* close and remove temp file */
close(fd);
unlink(file_name);
#else
/* On Windows, it generates a unique temporary file name but does not create
* or open the file */
if (_mktemp_s(file_name, name_len) != 0) {
goto fail;
}
#endif
return true;
fail:
return false;
}
#endif /* End of WASM_ENABLE_WAMR_COMPILER != 0 || WASM_ENABLE_JIT != 0 */