openldap/servers/slapd/acl.c
1998-09-12 04:33:13 +00:00

569 lines
14 KiB
C

/* acl.c - routines to parse and check acl's */
#include <stdio.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>
#include <regex.h>
#include "slap.h"
extern Attribute *attr_find();
extern struct acl *global_acl;
extern int global_default_access;
extern char *access2str();
extern char *dn_normalize_case();
int acl_access_allowed();
int access_allowed();
struct acl *acl_get_applicable();
static int regex_matches();
static string_expand(char *newbuf, int bufsiz, char *pattern,
char *match, regmatch_t *matches);
extern Entry * be_dn2entry(Backend *be, char *bdn, char **matched);
/*
* access_allowed - check whether dn is allowed the requested access
* to entry e, attribute attr, value val. if val is null, access to
* the whole attribute is assumed (all values). this routine finds
* the applicable acl and calls acl_access_allowed() to make the
* decision.
*
* returns 0 access NOT allowed
* 1 access allowed
*/
int
access_allowed(
Backend *be,
Connection *conn,
Operation *op,
Entry *e,
char *attr,
struct berval *val,
char *dn,
int access
)
{
int rc;
struct acl *a;
char *edn;
regmatch_t matches[MAXREMATCHES];
int i;
int n;
if ( be == NULL ) {
return( 0 );
}
edn = dn_normalize_case( strdup( e->e_dn ) );
Debug( LDAP_DEBUG_ACL, "\n=> access_allowed: entry (%s) attr (%s)\n",
e->e_dn, attr, 0 );
/* the lastmod attributes are ignored by ACL checking */
if ( strcasecmp( attr, "modifiersname" ) == 0 ||
strcasecmp( attr, "modifytimestamp" ) == 0 ||
strcasecmp( attr, "creatorsname" ) == 0 ||
strcasecmp( attr, "createtimestamp" ) == 0 )
{
Debug( LDAP_DEBUG_ACL, "LASTMOD attribute: %s access allowed\n",
attr, 0, 0 );
free( edn );
return(1);
}
memset(matches, 0, sizeof(matches));
a = acl_get_applicable( be, op, e, attr, edn, MAXREMATCHES, matches );
if (a) {
for (i = 0; i < MAXREMATCHES && matches[i].rm_so > 0; i++) {
Debug( LDAP_DEBUG_ARGS, "=> match[%d]: %d %d ",
i, matches[i].rm_so, matches[i].rm_eo );
if( matches[i].rm_so <= matches[0].rm_eo ) {
for ( n = matches[i].rm_so; n < matches[i].rm_eo; n++) {
Debug( LDAP_DEBUG_ARGS, "%c", edn[n], 0, 0 );
}
}
Debug( LDAP_DEBUG_ARGS, "\n", 0, 0, 0 );
}
}
rc = acl_access_allowed( a, be, conn, e, val, op, access, edn, matches );
free( edn );
Debug( LDAP_DEBUG_ACL, "\n=> access_allowed: exit (%s) attr (%s)\n",
e->e_dn, attr, 0);
return( rc );
}
/*
* acl_get_applicable - return the acl applicable to entry e, attribute
* attr. the acl returned is suitable for use in subsequent calls to
* acl_access_allowed().
*/
struct acl *
acl_get_applicable(
Backend *be,
Operation *op,
Entry *e,
char *attr,
char *edn,
int nmatch,
regmatch_t *matches
)
{
int i, j;
struct acl *a;
Debug( LDAP_DEBUG_ACL, "\n=> acl_get: entry (%s) attr (%s)\n",
e->e_dn, attr, 0 );
if ( be_isroot( be, op->o_dn ) ) {
Debug( LDAP_DEBUG_ACL,
"<= acl_get: no acl applicable to database root\n", 0, 0,
0 );
return( NULL );
}
Debug( LDAP_DEBUG_ARGS, "=> acl_get: edn %s\n", edn, 0, 0 );
/* check for a backend-specific acl that matches the entry */
for ( i = 1, a = be->be_acl; a != NULL; a = a->acl_next, i++ ) {
if (a->acl_dnpat != NULL) {
Debug( LDAP_DEBUG_TRACE, "=> dnpat: [%d] %s nsub: %d\n",
i, a->acl_dnpat, a->acl_dnre.re_nsub);
if (regexec(&a->acl_dnre, edn, nmatch, matches, 0))
continue;
else
Debug( LDAP_DEBUG_TRACE, "=> acl_get:[%d] backend ACL match\n",
i, 0, 0);
}
if ( a->acl_filter != NULL ) {
if ( test_filter( NULL, NULL, NULL, e, a->acl_filter ) != 0 ) {
continue;
}
}
Debug( LDAP_DEBUG_ARGS, "=> acl_get: [%d] check attr %s\n", i, attr, 0);
if ( attr == NULL || a->acl_attrs == NULL ||
charray_inlist( a->acl_attrs, attr ) )
{
Debug( LDAP_DEBUG_ACL, "<= acl_get: [%d] backend acl %s attr: %s\n",
i, e->e_dn, attr );
return( a );
}
matches[0].rm_so = matches[0].rm_eo = -1;
}
/* check for a global acl that matches the entry */
for ( i = 1, a = global_acl; a != NULL; a = a->acl_next, i++ ) {
if (a->acl_dnpat != NULL) {
Debug( LDAP_DEBUG_TRACE, "=> dnpat: [%d] %s nsub: %d\n",
i, a->acl_dnpat, a->acl_dnre.re_nsub);
if (regexec(&a->acl_dnre, edn, nmatch, matches, 0)) {
continue;
} else {
Debug( LDAP_DEBUG_TRACE, "=> acl_get: [%d] global ACL match\n",
i, 0, 0);
}
}
if ( a->acl_filter != NULL ) {
if ( test_filter( NULL, NULL, NULL, e, a->acl_filter ) != 0 ) {
continue;
}
}
Debug( LDAP_DEBUG_ARGS, "=> acl_get: [%d] check attr\n", i, 0, 0);
if ( attr == NULL || a->acl_attrs == NULL ||
charray_inlist( a->acl_attrs, attr ) )
{
Debug( LDAP_DEBUG_ACL, "<= acl_get: [%d] global acl %s attr: %s\n",
i, e->e_dn, attr );
return( a );
}
matches[0].rm_so = matches[0].rm_eo = -1;
}
Debug( LDAP_DEBUG_ACL, "<= acl_get: no match\n", 0, 0, 0 );
return( NULL );
}
/*
* acl_access_allowed - check whether the given acl allows dn the
* requested access to entry e, attribute attr, value val. if val
* is null, access to the whole attribute is assumed (all values).
*
* returns 0 access NOT allowed
* 1 access allowed
*/
int
acl_access_allowed(
struct acl *a,
Backend *be,
Connection *conn,
Entry *e,
struct berval *val,
Operation *op,
int access,
char *edn,
regmatch_t *matches
)
{
int i;
char *odn;
struct access *b;
Attribute *at;
struct berval bv;
int default_access;
Debug( LDAP_DEBUG_ACL,
"\n=> acl_access_allowed: %s access to entry \"%s\"\n",
access2str( access ), e->e_dn, 0 );
Debug( LDAP_DEBUG_ACL,
"\n=> acl_access_allowed: %s access to value \"%s\" by \"%s\"\n",
access2str( access ),
val ? val->bv_val : "any",
op->o_dn ? op->o_dn : "" );
if ( be_isroot( be, op->o_dn ) ) {
Debug( LDAP_DEBUG_ACL,
"<= acl_access_allowed: granted to database root\n",
0, 0, 0 );
return( 1 );
}
default_access = be->be_dfltaccess ? be->be_dfltaccess : global_default_access;
if ( a == NULL ) {
Debug( LDAP_DEBUG_ACL,
"<= acl_access_allowed: %s by default (no matching to)\n",
default_access >= access ? "granted" : "denied", 0, 0 );
return( default_access >= access );
}
odn = NULL;
if ( op->o_dn != NULL ) {
odn = dn_normalize_case( strdup( op->o_dn ) );
bv.bv_val = odn;
bv.bv_len = strlen( odn );
}
for ( i = 1, b = a->acl_access; b != NULL; b = b->a_next, i++ ) {
if ( b->a_dnpat != NULL ) {
Debug( LDAP_DEBUG_TRACE, "<= check a_dnpat: %s\n",
b->a_dnpat, 0, 0);
/*
* if access applies to the entry itself, and the
* user is bound as somebody in the same namespace as
* the entry, OR the given dn matches the dn pattern
*/
if ( strcasecmp( b->a_dnpat, "self" ) == 0 &&
op->o_dn != NULL && *(op->o_dn) && e->e_dn != NULL )
{
if ( strcasecmp( edn, op->o_dn ) == 0 ) {
Debug( LDAP_DEBUG_ACL,
"<= acl_access_allowed: matched by clause #%d access %s\n",
i, (b->a_access & ~ACL_SELF) >=
access ? "granted" : "denied", 0 );
if ( odn ) free( odn );
return( (b->a_access & ~ACL_SELF) >= access );
}
} else {
if ( regex_matches( b->a_dnpat, odn, edn, matches ) ) {
Debug( LDAP_DEBUG_ACL,
"<= acl_access_allowed: matched by clause #%d access %s\n",
i, (b->a_access & ~ACL_SELF) >= access ?
"granted" : "denied", 0 );
if ( odn ) free( odn );
return( (b->a_access & ~ACL_SELF) >= access );
}
}
}
if ( b->a_addrpat != NULL ) {
if ( regex_matches( b->a_addrpat, conn->c_addr, edn, matches ) ) {
Debug( LDAP_DEBUG_ACL,
"<= acl_access_allowed: matched by clause #%d access %s\n",
i, (b->a_access & ~ACL_SELF) >= access ?
"granted" : "denied", 0 );
if ( odn ) free( odn );
return( (b->a_access & ~ACL_SELF) >= access );
}
}
if ( b->a_domainpat != NULL ) {
Debug( LDAP_DEBUG_ARGS, "<= check a_domainpath: %s\n",
b->a_domainpat, 0, 0 );
if ( regex_matches( b->a_domainpat, conn->c_domain, edn, matches ) )
{
Debug( LDAP_DEBUG_ACL,
"<= acl_access_allowed: matched by clause #%d access %s\n",
i, (b->a_access & ~ACL_SELF) >= access ?
"granted" : "denied", 0 );
if ( odn ) free( odn );
return( (b->a_access & ~ACL_SELF) >= access );
}
}
if ( b->a_dnattr != NULL && op->o_dn != NULL ) {
Debug( LDAP_DEBUG_ARGS, "<= check a_dnattr: %s\n",
b->a_dnattr, 0, 0);
/* see if asker is listed in dnattr */
if ( (at = attr_find( e->e_attrs, b->a_dnattr )) != NULL &&
value_find( at->a_vals, &bv, at->a_syntax, 3 ) == 0 )
{
if ( (b->a_access & ACL_SELF) &&
(val == NULL || value_cmp( &bv, val, at->a_syntax, 2 )) )
{
continue;
}
if ( odn ) free( odn );
Debug( LDAP_DEBUG_ACL,
"<= acl_acces_allowed: matched by clause #%d access %s\n",
i, (b->a_access & ~ACL_SELF) >= access ?
"granted" : "denied", 0 );
return( (b->a_access & ~ACL_SELF) >= access );
}
/* asker not listed in dnattr - check for self access */
if ( ! (b->a_access & ACL_SELF) || val == NULL ||
value_cmp( &bv, val, at->a_syntax, 2 ) != 0 )
{
continue;
}
if ( odn ) free( odn );
Debug( LDAP_DEBUG_ACL,
"<= acl_access_allowed: matched by clause #%d (self) access %s\n",
i, (b->a_access & ~ACL_SELF) >= access ? "granted"
: "denied", 0 );
return( (b->a_access & ~ACL_SELF) >= access );
}
#ifdef ACLGROUP
if ( b->a_group != NULL && op->o_dn != NULL ) {
char buf[512];
/* b->a_group is an unexpanded entry name, expanded it should be an
* entry with objectclass group* and we test to see if odn is one of
* the values in the attribute uniquegroup
*/
Debug( LDAP_DEBUG_ARGS, "<= check a_group: %s\n",
b->a_group, 0, 0);
Debug( LDAP_DEBUG_ARGS, "<= check a_group: odn: %s\n",
odn, 0, 0);
/* see if asker is listed in dnattr */
string_expand(buf, sizeof(buf), b->a_group, edn, matches);
if (be_group(be, buf, odn) == 0) {
Debug( LDAP_DEBUG_ACL,
"<= acl_access_allowed: matched by clause #%d (group) access granted\n",
i, 0, 0 );
if ( odn ) free( odn );
return( (b->a_access & ~ACL_SELF) >= access );
}
}
#endif /* ACLGROUP */
}
if ( odn ) free( odn );
Debug( LDAP_DEBUG_ACL,
"<= acl_access_allowed: %s by default (no matching by)\n",
default_access >= access ? "granted" : "denied", 0, 0 );
return( default_access >= access );
}
/*
* acl_check_mods - check access control on the given entry to see if
* it allows the given modifications by the user associated with op.
* returns LDAP_SUCCESS mods allowed ok
* anything else mods not allowed - return is an error
* code indicating the problem
*/
int
acl_check_mods(
Backend *be,
Connection *conn,
Operation *op,
Entry *e,
LDAPMod *mods
)
{
int i;
struct acl *a;
char *edn;
edn = dn_normalize_case( strdup( e->e_dn ) );
for ( ; mods != NULL; mods = mods->mod_next ) {
regmatch_t matches[MAXREMATCHES];
/* the lastmod attributes are ignored by ACL checking */
if ( strcasecmp( mods->mod_type, "modifiersname" ) == 0 ||
strcasecmp( mods->mod_type, "modifytimestamp" ) == 0 ||
strcasecmp( mods->mod_type, "creatorsname" ) == 0 ||
strcasecmp( mods->mod_type, "createtimestamp" ) == 0 )
{
Debug( LDAP_DEBUG_ACL, "LASTMOD attribute: %s access allowed\n",
mods->mod_type, 0, 0 );
continue;
}
a = acl_get_applicable( be, op, e, mods->mod_type, edn,
MAXREMATCHES, matches );
switch ( mods->mod_op & ~LDAP_MOD_BVALUES ) {
case LDAP_MOD_REPLACE:
case LDAP_MOD_ADD:
if ( mods->mod_bvalues == NULL ) {
break;
}
for ( i = 0; mods->mod_bvalues[i] != NULL; i++ ) {
if ( ! acl_access_allowed( a, be, conn, e, mods->mod_bvalues[i],
op, ACL_WRITE, edn, matches) )
{
free(edn);
return( LDAP_INSUFFICIENT_ACCESS );
}
}
break;
case LDAP_MOD_DELETE:
if ( mods->mod_bvalues == NULL ) {
if ( ! acl_access_allowed( a, be, conn, e,
NULL, op, ACL_WRITE, edn, matches) )
{
free(edn);
return( LDAP_INSUFFICIENT_ACCESS );
}
break;
}
for ( i = 0; mods->mod_bvalues[i] != NULL; i++ ) {
if ( ! acl_access_allowed( a, be, conn, e, mods->mod_bvalues[i],
op, ACL_WRITE, edn, matches) )
{
free(edn);
return( LDAP_INSUFFICIENT_ACCESS );
}
}
break;
}
}
free(edn);
return( LDAP_SUCCESS );
}
static string_expand(
char *newbuf,
int bufsiz,
char *pat,
char *match,
regmatch_t *matches)
{
int size;
char *sp;
char *dp;
int flag;
size = 0;
newbuf[0] = '\0';
flag = 0;
for ( dp = newbuf, sp = pat; size < 512 && *sp ; sp++) {
/* did we previously see a $ */
if (flag) {
if (*sp == '$') {
*dp++ = '$';
size++;
} else if (*sp >= '0' && *sp <= '9' ) {
int n;
int i;
char *ep;
int l;
n = *sp - '0';
*dp = '\0';
i = matches[n].rm_so;
l = matches[n].rm_eo;
for ( ; size < 512 && i < l; size++, i++ ) {
*dp++ = match[i];
size++;
}
*dp = '\0';
}
flag = 0;
} else {
if (*sp == '$') {
flag = 1;
} else {
*dp++ = *sp;
size++;
}
}
}
*dp = '\0';
Debug( LDAP_DEBUG_TRACE, "=> string_expand: pattern: %s\n", pat, 0, 0 );
Debug( LDAP_DEBUG_TRACE, "=> string_expand: expanded: %s\n", newbuf, 0, 0 );
}
static int
regex_matches(
char *pat, /* pattern to expand and match against */
char *str, /* string to match against pattern */
char *buf, /* buffer with $N expansion variables */
regmatch_t *matches /* offsets in buffer for $N expansion variables */
)
{
regex_t re;
char newbuf[512];
int rc;
string_expand(newbuf, sizeof(newbuf), pat, buf, matches);
if (( rc = regcomp(&re, newbuf, REG_EXTENDED|REG_ICASE))) {
char error[512];
regerror(rc, &re, error, sizeof(error));
Debug( LDAP_DEBUG_ANY,
"compile( \"%s\", \"%s\") failed %s\n",
pat, str, error );
return( 0 );
}
rc = regexec(&re, str, 0, NULL, 0);
regfree( &re );
Debug( LDAP_DEBUG_TRACE,
"=> regex_matches: string: %s\n", str, 0, 0 );
Debug( LDAP_DEBUG_TRACE,
"=> regex_matches: rc: %d %s\n",
rc, !rc ? "matches" : "no matches", 0 );
return( !rc );
}