1#define _GNU_SOURCE
 2#include "pwf.h"
 3#include <grp.h>
 4#include <string.h>
 5#include <limits.h>
 6#include <stdio.h>
 7#include <stdlib.h>
 8#include <byteswap.h>
 9#include <errno.h>
10#include "nscd.h"
11
12int getgrouplist(const char *user, gid_t gid, gid_t *groups, int *ngroups)
13{
14	int rv, nlim, ret = -1;
15	ssize_t i, n = 1;
16	struct group gr;
17	struct group *res;
18	FILE *f;
19	int swap = 0;
20	int32_t resp[INITGR_LEN];
21	uint32_t *nscdbuf = 0;
22	char *buf = 0;
23	char **mem = 0;
24	size_t nmem = 0;
25	size_t size;
26	nlim = *ngroups;
27	if (nlim >= 1) *groups++ = gid;
28
29	f = __nscd_query(GETINITGR, user, resp, sizeof resp, &swap);
30	if (!f) goto cleanup;
31	if (resp[INITGRFOUND]) {
32		nscdbuf = calloc(resp[INITGRNGRPS], sizeof(uint32_t));
33		if (!nscdbuf) goto cleanup;
34		size_t nbytes = sizeof(*nscdbuf)*resp[INITGRNGRPS];
35		if (nbytes && !fread(nscdbuf, nbytes, 1, f)) {
36			if (!ferror(f)) errno = EIO;
37			goto cleanup;
38		}
39		if (swap) {
40			for (i = 0; i < resp[INITGRNGRPS]; i++)
41				nscdbuf[i] = bswap_32(nscdbuf[i]);
42		}
43	}
44	fclose(f);
45
46	f = fopen("/etc/group", "rbe");
47	if (!f && errno != ENOENT && errno != ENOTDIR)
48		goto cleanup;
49
50	if (f) {
51		while (!(rv = __getgrent_a(f, &gr, &buf, &size, &mem, &nmem, &res)) && res) {
52			if (nscdbuf)
53				for (i=0; i < resp[INITGRNGRPS]; i++) {
54					if (nscdbuf[i] == gr.gr_gid) nscdbuf[i] = gid;
55				}
56			for (i=0; gr.gr_mem[i] && strcmp(user, gr.gr_mem[i]); i++);
57			if (!gr.gr_mem[i]) continue;
58			if (++n <= nlim) *groups++ = gr.gr_gid;
59		}
60		if (rv) {
61			errno = rv;
62			goto cleanup;
63		}
64	}
65	if (nscdbuf) {
66		for(i=0; i < resp[INITGRNGRPS]; i++) {
67			if (nscdbuf[i] != gid)
68				if(++n <= nlim) *groups++ = nscdbuf[i];
69		}
70	}
71
72	ret = n > nlim ? -1 : n;
73	*ngroups = n;
74
75cleanup:
76	if (f) fclose(f);
77	free(nscdbuf);
78	free(buf);
79	free(mem);
80	return ret;
81}