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/*
* Load BSD executables.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see <http://www.gnu.org/licenses/>.
*/
#include "qemu/osdep.h"
#include "qemu.h"
/* ??? This should really be somewhere else. */
abi_long memcpy_to_target(abi_ulong dest, const void *src,
unsigned long len)
{
void *host_ptr;
host_ptr = lock_user(VERIFY_WRITE, dest, len, 0);
if (!host_ptr) {
return -TARGET_EFAULT;
}
memcpy(host_ptr, src, len);
unlock_user(host_ptr, dest, 1);
return 0;
}
static int count(char **vec)
{
int i;
for (i = 0; *vec; i++) {
vec++;
}
return i;
}
static int prepare_binprm(struct bsd_binprm *bprm)
{
struct stat st;
int mode;
int retval;
if (fstat(bprm->fd, &st) < 0) {
return -errno;
}
mode = st.st_mode;
if (!S_ISREG(mode)) { /* Must be regular file */
return -EACCES;
}
if (!(mode & 0111)) { /* Must have at least one execute bit set */
return -EACCES;
}
bprm->e_uid = geteuid();
bprm->e_gid = getegid();
/* Set-uid? */
if (mode & S_ISUID) {
bprm->e_uid = st.st_uid;
}
/* Set-gid? */
/*
* If setgid is set but no group execute bit then this
* is a candidate for mandatory locking, not a setgid
* executable.
*/
if ((mode & (S_ISGID | S_IXGRP)) == (S_ISGID | S_IXGRP)) {
bprm->e_gid = st.st_gid;
}
memset(bprm->buf, 0, sizeof(bprm->buf));
retval = lseek(bprm->fd, 0L, SEEK_SET);
if (retval >= 0) {
retval = read(bprm->fd, bprm->buf, 128);
}
if (retval < 0) {
perror("prepare_binprm");
exit(-1);
} else {
return retval;
}
}
/* Construct the envp and argv tables on the target stack. */
abi_ulong loader_build_argptr(int envc, int argc, abi_ulong sp,
abi_ulong stringp)
{
int n = sizeof(abi_ulong);
abi_ulong envp;
abi_ulong argv;
sp -= (envc + 1) * n;
envp = sp;
sp -= (argc + 1) * n;
argv = sp;
sp -= n;
/* FIXME - handle put_user() failures */
put_user_ual(argc, sp);
while (argc-- > 0) {
/* FIXME - handle put_user() failures */
put_user_ual(stringp, argv);
argv += n;
stringp += target_strlen(stringp) + 1;
}
/* FIXME - handle put_user() failures */
put_user_ual(0, argv);
while (envc-- > 0) {
/* FIXME - handle put_user() failures */
put_user_ual(stringp, envp);
envp += n;
stringp += target_strlen(stringp) + 1;
}
/* FIXME - handle put_user() failures */
put_user_ual(0, envp);
return sp;
}
static bool is_there(const char *candidate)
{
struct stat fin;
/* XXX work around access(2) false positives for superuser */
if (access(candidate, X_OK) == 0 && stat(candidate, &fin) == 0 &&
S_ISREG(fin.st_mode) && (getuid() != 0 ||
(fin.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH)) != 0)) {
return true;
}
return false;
}
int loader_exec(const char *filename, char **argv, char **envp,
struct target_pt_regs *regs, struct image_info *infop,
struct bsd_binprm *bprm)
{
char *path, fullpath[PATH_MAX];
int retval, i;
bprm->p = TARGET_PAGE_SIZE * MAX_ARG_PAGES;
for (i = 0; i < MAX_ARG_PAGES; i++) { /* clear page-table */
bprm->page[i] = NULL;
}
if (strchr(filename, '/') != NULL) {
path = realpath(filename, fullpath);
if (path == NULL) {
/* Failed to resolve. */
return -1;
}
if (!is_there(path)) {
return -1;
}
} else {
path = g_find_program_in_path(filename);
if (path == NULL) {
return -1;
}
}
retval = open(path, O_RDONLY);
if (retval < 0) {
g_free(path);
return retval;
}
bprm->fullpath = path;
bprm->fd = retval;
bprm->filename = (char *)filename;
bprm->argc = count(argv);
bprm->argv = argv;
bprm->envc = count(envp);
bprm->envp = envp;
retval = prepare_binprm(bprm);
if (retval >= 0) {
if (bprm->buf[0] == 0x7f
&& bprm->buf[1] == 'E'
&& bprm->buf[2] == 'L'
&& bprm->buf[3] == 'F') {
retval = load_elf_binary(bprm, regs, infop);
} else {
fprintf(stderr, "Unknown binary format\n");
return -1;
}
}
if (retval >= 0) {
/* success. Initialize important registers */
do_init_thread(regs, infop);
return retval;
}
/* Something went wrong, return the inode and free the argument pages*/
for (i = 0 ; i < MAX_ARG_PAGES ; i++) {
g_free(bprm->page[i]);
}
return retval;
}
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