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/** BEGIN COPYRIGHT BLOCK
* Copyright (C) 2001 Sun Microsystems, Inc. Used by permission.
* Copyright (C) 2010 Red Hat, Inc.
* All rights reserved.
*
* License: GPL (version 3 or any later version).
* See LICENSE for details.
* END COPYRIGHT BLOCK **/
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <ldap.h>
#include "slap.h"
#define BEGIN do {
#define END \
} \
while (0) \
;
/* ------------------------------------------------------------
* LDAPProxyAuth
*
* ProxyAuthControl ::= SEQUENCE {
* authorizationDN LDAPDN
* }
*/
struct LDAPProxyAuth
{
char *auth_dn;
};
typedef struct LDAPProxyAuth LDAPProxyAuth;
/*
* delete_LDAPProxyAuth
*/
static void
delete_LDAPProxyAuth(LDAPProxyAuth *spec)
{
if (!spec)
return;
slapi_ch_free((void **)&spec->auth_dn);
slapi_ch_free((void **)&spec);
}
/*
* parse_LDAPProxyAuth
*
* Parse a BER encoded value into the compoents of the LDAP ProxyAuth control.
* The 'version' parameter should be 1 or 2.
*
* Returns an LDAP error code (LDAP_SUCCESS if all goes well) and sets
* *errtextp if appropriate.
*/
static int
parse_LDAPProxyAuth(struct berval *spec_ber, int version, char **errtextp, LDAPProxyAuth **out)
{
int lderr = LDAP_OPERATIONS_ERROR; /* pessimistic */
LDAPProxyAuth *spec = NULL;
BerElement *ber = NULL;
char *errstring = "unable to parse proxied authorization control";
Slapi_DN *sdn = NULL;
BEGIN
ber_tag_t tag;
if (version != 1 && version != 2) {
break;
}
if (!BV_HAS_DATA(spec_ber)) {
break;
}
/* create_LDAPProxyAuth */
spec = (LDAPProxyAuth *)slapi_ch_calloc(1, sizeof(LDAPProxyAuth));
if (!spec) {
break;
}
if (version == 2 && (spec_ber->bv_val[0] != CHAR_OCTETSTRING)) {
/* This doesn't start with an octet string, so just use the actual value */
spec->auth_dn = slapi_ch_strdup(spec_ber->bv_val);
} else {
ber = ber_init(spec_ber);
if (!ber) {
break;
}
if (version == 1) {
tag = ber_scanf(ber, "{a}", &spec->auth_dn);
} else {
tag = ber_scanf(ber, "a", &spec->auth_dn);
}
if (tag == LBER_ERROR) {
lderr = LDAP_PROTOCOL_ERROR;
break;
}
}
/*
* In version 2 of the control, the control value is actually an
* authorization ID (see section 9 of RFC 2829). We only support
* the "dnAuthzId" flavor, which looks like "dn:<DN>" where <DN> is
* an actual DN, e.g., "dn:uid=bjensen,dc=example,dc=com". So we
* need to strip off the dn: if present and reject the operation if
* not.
*/
if (2 == version) {
if (NULL == spec->auth_dn || strlen(spec->auth_dn) < 3 ||
strncmp("dn:", spec->auth_dn, 3) != 0) {
lderr = LDAP_INSUFFICIENT_ACCESS; /* per Proxied Auth. I-D */
errstring = "proxied authorization id must be a DN (dn:...)";
break;
}
/* memmove is safe for overlapping copy */
memmove(spec->auth_dn, spec->auth_dn + 3, strlen(spec->auth_dn) - 2); /* 1 for '\0' */
}
lderr = LDAP_SUCCESS; /* got it! */
sdn = slapi_sdn_new_dn_passin(spec->auth_dn);
spec->auth_dn = slapi_ch_strdup(slapi_sdn_get_ndn(sdn));
slapi_sdn_free(&sdn);
if (NULL == spec->auth_dn) {
lderr = LDAP_INVALID_SYNTAX;
}
END
/* Cleanup */
if (ber) ber_free(ber, 1);
if (LDAP_SUCCESS != lderr) {
if (spec)
delete_LDAPProxyAuth(spec);
spec = 0;
if (NULL != errtextp) {
*errtextp = errstring;
}
}
*out = spec;
return lderr;
}
/*
* proxyauth_dn - find the users DN in the proxyauth control if it is
* present. The return value has been malloced for you.
*
* Returns an LDAP error code. If anything than LDAP_SUCCESS is returned,
* the error should be returned to the client. LDAP_SUCCESS is always
* returned if the proxy auth control is not present or not critical.
*/
int
proxyauth_get_dn(Slapi_PBlock *pb, char **proxydnp, char **errtextp)
{
char *dn = 0;
LDAPProxyAuth *spec = 0;
int rv, lderr = LDAP_SUCCESS; /* optimistic */
BEGIN
struct berval *spec_ber;
LDAPControl **controls;
int present;
int critical;
int version = 1;
rv = slapi_pblock_get(pb, SLAPI_REQCONTROLS, &controls);
if (rv)
break;
present = slapi_control_present(controls, LDAP_CONTROL_PROXYAUTH,
&spec_ber, &critical);
if (!present) {
present = slapi_control_present(controls, LDAP_CONTROL_PROXIEDAUTH,
&spec_ber, &critical);
if (!present)
break;
version = 2;
/*
* Note the according to the Proxied Authorization I-D, the
* control is always supposed to be marked critical by the
* client. If it is not, we return a protocolError.
*/
if (!critical) {
lderr = LDAP_PROTOCOL_ERROR;
if (NULL != errtextp) {
*errtextp = "proxy control must be marked critical";
}
break;
}
}
rv = parse_LDAPProxyAuth(spec_ber, version, errtextp, &spec);
if (LDAP_SUCCESS != rv) {
if (critical) {
lderr = LDAP_UNAVAILABLE_CRITICAL_EXTENSION;
} else {
lderr = rv;
}
break;
}
dn = slapi_ch_strdup(spec->auth_dn);
if (slapi_dn_isroot(dn)) {
if (critical)
lderr = LDAP_UNAVAILABLE_CRITICAL_EXTENSION;
else
lderr = LDAP_UNWILLING_TO_PERFORM;
*errtextp = "Proxy dn should not be rootdn";
break;
}
END
if (spec) delete_LDAPProxyAuth(spec);
if (NULL != proxydnp) {
*proxydnp = dn;
} else {
slapi_ch_free_string(&dn);
}
return lderr;
}
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