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| | #include <pthread.h>
#include <byteswap.h>
#include <string.h>
#include <unistd.h>
#include "pwf.h"
#include "nscd.h"
static char *itoa(char *p, uint32_t x)
{
// number of digits in a uint32_t + NUL
p += 11;
*--p = 0;
do {
*--p = '0' + x % 10;
x /= 10;
} while (x);
return p;
}
int __getgr_a(const char *name, gid_t gid, struct group *gr, char **buf, size_t *size, char ***mem, size_t *nmem, struct group **res)
{
FILE *f;
int rv = 0;
int cs;
*res = 0;
pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs);
f = fopen("/etc/group", "rbe");
if (!f) {
rv = errno;
goto done;
}
while (!(rv = __getgrent_a(f, gr, buf, size, mem, nmem, res)) && *res) {
if (name && !strcmp(name, (*res)->gr_name)
|| !name && (*res)->gr_gid == gid) {
break;
}
}
fclose(f);
if (!*res && (rv == 0 || rv == ENOENT || rv == ENOTDIR)) {
int32_t req = name ? GETGRBYNAME : GETGRBYGID;
int32_t i;
const char *key;
int32_t groupbuf[GR_LEN] = {0};
size_t len = 0;
size_t grlist_len = 0;
char gidbuf[11] = {0};
int swap = 0;
char *ptr;
if (name) {
key = name;
} else {
if (gid < 0 || gid > UINT32_MAX) {
rv = 0;
goto done;
}
key = itoa(gidbuf, gid);
}
f = __nscd_query(req, key, groupbuf, sizeof groupbuf, &swap);
if (!f) { rv = errno; goto done; }
if (!groupbuf[GRFOUND]) { rv = 0; goto cleanup_f; }
if (!groupbuf[GRNAMELEN] || !groupbuf[GRPASSWDLEN]) {
rv = EIO;
goto cleanup_f;
}
if (groupbuf[GRNAMELEN] > SIZE_MAX - groupbuf[GRPASSWDLEN]) {
rv = ENOMEM;
goto cleanup_f;
}
len = groupbuf[GRNAMELEN] + groupbuf[GRPASSWDLEN];
for (i = 0; i < groupbuf[GRMEMCNT]; i++) {
uint32_t name_len;
if (fread(&name_len, sizeof name_len, 1, f) < 1) {
rv = ferror(f) ? errno : EIO;
goto cleanup_f;
}
if (swap) {
name_len = bswap_32(name_len);
}
if (name_len > SIZE_MAX - grlist_len
|| name_len > SIZE_MAX - len) {
rv = ENOMEM;
goto cleanup_f;
}
len += name_len;
grlist_len += name_len;
}
if (len > *size || !*buf) {
char *tmp = realloc(*buf, len);
if (!tmp) {
rv = errno;
goto cleanup_f;
}
*buf = tmp;
*size = len;
}
if (!fread(*buf, len, 1, f)) {
rv = ferror(f) ? errno : EIO;
goto cleanup_f;
}
if (groupbuf[GRMEMCNT] + 1 > *nmem) {
if (groupbuf[GRMEMCNT] + 1 > SIZE_MAX/sizeof(char*)) {
rv = ENOMEM;
goto cleanup_f;
}
char **tmp = realloc(*mem, (groupbuf[GRMEMCNT]+1)*sizeof(char*));
if (!tmp) {
rv = errno;
goto cleanup_f;
}
*mem = tmp;
*nmem = groupbuf[GRMEMCNT] + 1;
}
if (groupbuf[GRMEMCNT]) {
mem[0][0] = *buf + groupbuf[GRNAMELEN] + groupbuf[GRPASSWDLEN];
for (ptr = mem[0][0], i = 0; ptr != mem[0][0]+grlist_len; ptr++)
if (!*ptr) mem[0][++i] = ptr+1;
mem[0][i] = 0;
if (i != groupbuf[GRMEMCNT]) {
rv = EIO;
goto cleanup_f;
}
} else {
mem[0][0] = 0;
}
gr->gr_name = *buf;
gr->gr_passwd = gr->gr_name + groupbuf[GRNAMELEN];
gr->gr_gid = groupbuf[GRGID];
gr->gr_mem = *mem;
if (gr->gr_passwd[-1]
|| gr->gr_passwd[groupbuf[GRPASSWDLEN]-1]) {
rv = EIO;
goto cleanup_f;
}
if (name && strcmp(name, gr->gr_name)
|| !name && gid != gr->gr_gid) {
rv = EIO;
goto cleanup_f;
}
*res = gr;
cleanup_f:
fclose(f);
goto done;
}
done:
pthread_setcancelstate(cs, 0);
if (rv) errno = rv;
return rv;
}
|