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
getgrouplist(const char * user,gid_t gid,gid_t * groups,int * ngroups)12 int 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
75 cleanup:
76 if (f) fclose(f);
77 free(nscdbuf);
78 free(buf);
79 free(mem);
80 return ret;
81 }
82