gen_gr.c revision 9525b14bcdeb5b5f6f95ab27c2f48f18bd2ec829
/*
* Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
* Copyright (c) 1996-1999 by Internet Software Consortium.
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
* OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#if !defined(LINT) && !defined(CODECENTER)
static const char rcsid[] = "$Id: gen_gr.c,v 1.8 2005/04/27 04:56:23 sra Exp $";
#endif
/* Imports */
#include "port_before.h"
#ifndef WANT_IRS_GR
static int __bind_irs_gr_unneeded;
#else
#include <sys/types.h>
#include <isc/assertions.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <netinet/in.h>
#include <arpa/nameser.h>
#include <resolv.h>
#include <isc/memcluster.h>
#include <irs.h>
#include "port_after.h"
#include "irs_p.h"
#include "gen_p.h"
/* Definitions */
struct pvt {
struct irs_rule * rules;
struct irs_rule * rule;
struct irs_gr * gr;
/*
* Need space to store the entries read from the group file.
* The members list also needs space per member, and the
* strings making up the user names must be allocated
* somewhere. Rather than doing lots of small allocations,
* we keep one buffer and resize it as needed.
*/
struct group group;
size_t nmemb; /*%< Malloc'd max index of gr_mem[]. */
char * membuf;
size_t membufsize;
struct __res_state * res;
void (*free_res)(void *);
};
/* Forward */
static void gr_close(struct irs_gr *);
static struct group * gr_next(struct irs_gr *);
static struct group * gr_byname(struct irs_gr *, const char *);
static struct group * gr_bygid(struct irs_gr *, gid_t);
static void gr_rewind(struct irs_gr *);
static int gr_list(struct irs_gr *, const char *,
gid_t, gid_t *, int *);
static void gr_minimize(struct irs_gr *);
static struct __res_state * gr_res_get(struct irs_gr *);
static void gr_res_set(struct irs_gr *,
struct __res_state *,
void (*)(void *));
static int grmerge(struct irs_gr *gr, const struct group *src,
int preserve);
static int countvec(char **vec);
static int isnew(char **old, char *new);
static int countnew(char **old, char **new);
static size_t sizenew(char **old, char **new);
static int newgid(int, gid_t *, gid_t);
/* Macros */
#define FREE_IF(x) do { if ((x) != NULL) { free(x); (x) = NULL; } } while (0)
/* Public */
struct irs_gr *
irs_gen_gr(struct irs_acc *this) {
struct gen_p *accpvt = (struct gen_p *)this->private;
struct irs_gr *gr;
struct pvt *pvt;
if (!(gr = memget(sizeof *gr))) {
errno = ENOMEM;
return (NULL);
}
memset(gr, 0x5e, sizeof *gr);
if (!(pvt = memget(sizeof *pvt))) {
memput(gr, sizeof *gr);
errno = ENOMEM;
return (NULL);
}
memset(pvt, 0, sizeof *pvt);
pvt->rules = accpvt->map_rules[irs_gr];
pvt->rule = pvt->rules;
gr->private = pvt;
gr->close = gr_close;
gr->next = gr_next;
gr->byname = gr_byname;
gr->bygid = gr_bygid;
gr->rewind = gr_rewind;
gr->list = gr_list;
gr->minimize = gr_minimize;
gr->res_get = gr_res_get;
gr->res_set = gr_res_set;
return (gr);
}
/* Methods. */
static void
gr_close(struct irs_gr *this) {
struct pvt *pvt = (struct pvt *)this->private;
memput(pvt, sizeof *pvt);
memput(this, sizeof *this);
}
static struct group *
gr_next(struct irs_gr *this) {
struct pvt *pvt = (struct pvt *)this->private;
struct group *rval;
struct irs_gr *gr;
while (pvt->rule) {
gr = pvt->rule->inst->gr;
rval = (*gr->next)(gr);
if (rval)
return (rval);
if (!(pvt->rule->flags & IRS_CONTINUE))
break;
pvt->rule = pvt->rule->next;
if (pvt->rule) {
gr = pvt->rule->inst->gr;
(*gr->rewind)(gr);
}
}
return (NULL);
}
static struct group *
gr_byname(struct irs_gr *this, const char *name) {
struct pvt *pvt = (struct pvt *)this->private;
struct irs_rule *rule;
struct group *tval;
struct irs_gr *gr;
int dirty;
dirty = 0;
for (rule = pvt->rules; rule; rule = rule->next) {
gr = rule->inst->gr;
tval = (*gr->byname)(gr, name);
if (tval) {
if (!grmerge(this, tval, dirty++))
return (NULL);
if (!(rule->flags & IRS_MERGE))
break;
} else {
if (!(rule->flags & IRS_CONTINUE))
break;
}
}
if (dirty)
return (&pvt->group);
return (NULL);
}
static struct group *
gr_bygid(struct irs_gr *this, gid_t gid) {
struct pvt *pvt = (struct pvt *)this->private;
struct irs_rule *rule;
struct group *tval;
struct irs_gr *gr;
int dirty;
dirty = 0;
for (rule = pvt->rules; rule; rule = rule->next) {
gr = rule->inst->gr;
tval = (*gr->bygid)(gr, gid);
if (tval) {
if (!grmerge(this, tval, dirty++))
return (NULL);
if (!(rule->flags & IRS_MERGE))
break;
} else {
if (!(rule->flags & IRS_CONTINUE))
break;
}
}
if (dirty)
return (&pvt->group);
return (NULL);
}
static void
gr_rewind(struct irs_gr *this) {
struct pvt *pvt = (struct pvt *)this->private;
struct irs_gr *gr;
pvt->rule = pvt->rules;
if (pvt->rule) {
gr = pvt->rule->inst->gr;
(*gr->rewind)(gr);
}
}
static int
gr_list(struct irs_gr *this, const char *name,
gid_t basegid, gid_t *groups, int *ngroups)
{
struct pvt *pvt = (struct pvt *)this->private;
struct irs_rule *rule;
struct irs_gr *gr;
int t_ngroups, maxgroups;
gid_t *t_groups;
int n, t, rval = 0;
maxgroups = *ngroups;
*ngroups = 0;
t_groups = (gid_t *)malloc(maxgroups * sizeof(gid_t));
if (!t_groups) {
errno = ENOMEM;
return (-1);
}
for (rule = pvt->rules; rule; rule = rule->next) {
t_ngroups = maxgroups;
gr = rule->inst->gr;
t = (*gr->list)(gr, name, basegid, t_groups, &t_ngroups);
for (n = 0; n < t_ngroups; n++) {
if (newgid(*ngroups, groups, t_groups[n])) {
if (*ngroups == maxgroups) {
rval = -1;
goto done;
}
groups[(*ngroups)++] = t_groups[n];
}
}
if (t == 0) {
if (!(rule->flags & IRS_MERGE))
break;
} else {
if (!(rule->flags & IRS_CONTINUE))
break;
}
}
done:
free(t_groups);
return (rval);
}
static void
gr_minimize(struct irs_gr *this) {
struct pvt *pvt = (struct pvt *)this->private;
struct irs_rule *rule;
for (rule = pvt->rules; rule != NULL; rule = rule->next) {
struct irs_gr *gr = rule->inst->gr;
(*gr->minimize)(gr);
}
}
static struct __res_state *
gr_res_get(struct irs_gr *this) {
struct pvt *pvt = (struct pvt *)this->private;
if (!pvt->res) {
struct __res_state *res;
res = (struct __res_state *)malloc(sizeof *res);
if (!res) {
errno = ENOMEM;
return (NULL);
}
memset(res, 0, sizeof *res);
gr_res_set(this, res, free);
}
return (pvt->res);
}
static void
gr_res_set(struct irs_gr *this, struct __res_state *res,
void (*free_res)(void *)) {
struct pvt *pvt = (struct pvt *)this->private;
struct irs_rule *rule;
if (pvt->res && pvt->free_res) {
res_nclose(pvt->res);
(*pvt->free_res)(pvt->res);
}
pvt->res = res;
pvt->free_res = free_res;
for (rule = pvt->rules; rule != NULL; rule = rule->next) {
struct irs_gr *gr = rule->inst->gr;
if (gr->res_set)
(*gr->res_set)(gr, pvt->res, NULL);
}
}
/* Private. */
static int
grmerge(struct irs_gr *this, const struct group *src, int preserve) {
struct pvt *pvt = (struct pvt *)this->private;
char *cp, **m, **p, *oldmembuf, *ep;
int n, ndst, nnew;
size_t used;
if (!preserve) {
pvt->group.gr_gid = src->gr_gid;
if (pvt->nmemb < 1) {
m = malloc(sizeof *m);
if (m == NULL) {
/* No harm done, no work done. */
return (0);
}
pvt->group.gr_mem = m;
pvt->nmemb = 1;
}
pvt->group.gr_mem[0] = NULL;
}
ndst = countvec(pvt->group.gr_mem);
nnew = countnew(pvt->group.gr_mem, src->gr_mem);
/*
* Make sure destination member array is large enough.
* p points to new portion.
*/
n = ndst + nnew + 1;
if ((size_t)n > pvt->nmemb) {
m = realloc(pvt->group.gr_mem, n * sizeof *m);
if (m == NULL) {
/* No harm done, no work done. */
return (0);
}
pvt->group.gr_mem = m;
pvt->nmemb = n;
}
p = pvt->group.gr_mem + ndst;
/*
* Enlarge destination membuf; cp points at new portion.
*/
n = sizenew(pvt->group.gr_mem, src->gr_mem);
INSIST((nnew == 0) == (n == 0));
if (!preserve) {
n += strlen(src->gr_name) + 1;
n += strlen(src->gr_passwd) + 1;
}
if (n == 0) {
/* No work to do. */
return (1);
}
used = preserve ? pvt->membufsize : 0;
cp = malloc(used + n);
if (cp == NULL) {
/* No harm done, no work done. */
return (0);
}
ep = cp + used + n;
if (used != 0)
memcpy(cp, pvt->membuf, used);
oldmembuf = pvt->membuf;
pvt->membuf = cp;
pvt->membufsize = used + n;
cp += used;
/*
* Adjust group.gr_mem.
*/
if (pvt->membuf != oldmembuf)
for (m = pvt->group.gr_mem; *m; m++)
*m = pvt->membuf + (*m - oldmembuf);
/*
* Add new elements.
*/
for (m = src->gr_mem; *m; m++)
if (isnew(pvt->group.gr_mem, *m)) {
*p++ = cp;
*p = NULL;
n = strlen(*m) + 1;
if (n > ep - cp) {
FREE_IF(oldmembuf);
return (0);
}
strcpy(cp, *m); /* (checked) */
cp += n;
}
if (preserve) {
pvt->group.gr_name = pvt->membuf +
(pvt->group.gr_name - oldmembuf);
pvt->group.gr_passwd = pvt->membuf +
(pvt->group.gr_passwd - oldmembuf);
} else {
pvt->group.gr_name = cp;
n = strlen(src->gr_name) + 1;
if (n > ep - cp) {
FREE_IF(oldmembuf);
return (0);
}
strcpy(cp, src->gr_name); /* (checked) */
cp += n;
pvt->group.gr_passwd = cp;
n = strlen(src->gr_passwd) + 1;
if (n > ep - cp) {
FREE_IF(oldmembuf);
return (0);
}
strcpy(cp, src->gr_passwd); /* (checked) */
cp += n;
}
FREE_IF(oldmembuf);
INSIST(cp >= pvt->membuf && cp <= &pvt->membuf[pvt->membufsize]);
return (1);
}
static int
countvec(char **vec) {
int n = 0;
while (*vec++)
n++;
return (n);
}
static int
isnew(char **old, char *new) {
for (; *old; old++)
if (strcmp(*old, new) == 0)
return (0);
return (1);
}
static int
countnew(char **old, char **new) {
int n = 0;
for (; *new; new++)
n += isnew(old, *new);
return (n);
}
static size_t
sizenew(char **old, char **new) {
size_t n = 0;
for (; *new; new++)
if (isnew(old, *new))
n += strlen(*new) + 1;
return (n);
}
static int
newgid(int ngroups, gid_t *groups, gid_t group) {
ngroups--, groups++;
for (; ngroups-- > 0; groups++)
if (*groups == group)
return (0);
return (1);
}
#endif /* WANT_IRS_GR */
/*! \file */