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samba-mirror/source3/libads/sasl.c
Günther Deschner e7a6a3ec0d s3: avoid global include of ads.h.
Guenther
2010-08-05 00:32:02 +02:00

1155 lines
30 KiB
C

/*
Unix SMB/CIFS implementation.
ads sasl code
Copyright (C) Andrew Tridgell 2001
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include "includes.h"
#include "../libcli/auth/spnego.h"
#include "../libcli/auth/ntlmssp.h"
#include "ads.h"
#include "smb_krb5.h"
#ifdef HAVE_LDAP
static ADS_STATUS ads_sasl_ntlmssp_wrap(ADS_STRUCT *ads, uint8 *buf, uint32 len)
{
struct ntlmssp_state *ntlmssp_state =
(struct ntlmssp_state *)ads->ldap.wrap_private_data;
ADS_STATUS status;
NTSTATUS nt_status;
DATA_BLOB sig;
TALLOC_CTX *frame;
uint8 *dptr = ads->ldap.out.buf + (4 + NTLMSSP_SIG_SIZE);
frame = talloc_stackframe();
/* copy the data to the right location */
memcpy(dptr, buf, len);
/* create the signature and may encrypt the data */
if (ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_SEAL) {
nt_status = ntlmssp_seal_packet(ntlmssp_state,
frame,
dptr, len,
dptr, len,
&sig);
} else {
nt_status = ntlmssp_sign_packet(ntlmssp_state,
frame,
dptr, len,
dptr, len,
&sig);
}
status = ADS_ERROR_NT(nt_status);
if (!ADS_ERR_OK(status)) return status;
/* copy the signature to the right location */
memcpy(ads->ldap.out.buf + 4,
sig.data, NTLMSSP_SIG_SIZE);
TALLOC_FREE(frame);
/* set how many bytes must be written to the underlying socket */
ads->ldap.out.left = 4 + NTLMSSP_SIG_SIZE + len;
return ADS_SUCCESS;
}
static ADS_STATUS ads_sasl_ntlmssp_unwrap(ADS_STRUCT *ads)
{
struct ntlmssp_state *ntlmssp_state =
(struct ntlmssp_state *)ads->ldap.wrap_private_data;
ADS_STATUS status;
NTSTATUS nt_status;
DATA_BLOB sig;
uint8 *dptr = ads->ldap.in.buf + (4 + NTLMSSP_SIG_SIZE);
uint32 dlen = ads->ldap.in.ofs - (4 + NTLMSSP_SIG_SIZE);
/* wrap the signature into a DATA_BLOB */
sig = data_blob_const(ads->ldap.in.buf + 4, NTLMSSP_SIG_SIZE);
/* verify the signature and maybe decrypt the data */
if (ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_SEAL) {
nt_status = ntlmssp_unseal_packet(ntlmssp_state,
dptr, dlen,
dptr, dlen,
&sig);
} else {
nt_status = ntlmssp_check_packet(ntlmssp_state,
dptr, dlen,
dptr, dlen,
&sig);
}
status = ADS_ERROR_NT(nt_status);
if (!ADS_ERR_OK(status)) return status;
/* set the amount of bytes for the upper layer and set the ofs to the data */
ads->ldap.in.left = dlen;
ads->ldap.in.ofs = 4 + NTLMSSP_SIG_SIZE;
return ADS_SUCCESS;
}
static void ads_sasl_ntlmssp_disconnect(ADS_STRUCT *ads)
{
struct ntlmssp_state *ntlmssp_state =
(struct ntlmssp_state *)ads->ldap.wrap_private_data;
TALLOC_FREE(ntlmssp_state);
ads->ldap.wrap_ops = NULL;
ads->ldap.wrap_private_data = NULL;
}
static const struct ads_saslwrap_ops ads_sasl_ntlmssp_ops = {
.name = "ntlmssp",
.wrap = ads_sasl_ntlmssp_wrap,
.unwrap = ads_sasl_ntlmssp_unwrap,
.disconnect = ads_sasl_ntlmssp_disconnect
};
/*
perform a LDAP/SASL/SPNEGO/NTLMSSP bind (just how many layers can
we fit on one socket??)
*/
static ADS_STATUS ads_sasl_spnego_ntlmssp_bind(ADS_STRUCT *ads)
{
DATA_BLOB msg1 = data_blob_null;
DATA_BLOB blob = data_blob_null;
DATA_BLOB blob_in = data_blob_null;
DATA_BLOB blob_out = data_blob_null;
struct berval cred, *scred = NULL;
int rc;
NTSTATUS nt_status;
ADS_STATUS status;
int turn = 1;
uint32 features = 0;
struct ntlmssp_state *ntlmssp_state;
nt_status = ntlmssp_client_start(NULL,
global_myname(),
lp_workgroup(),
lp_client_ntlmv2_auth(),
&ntlmssp_state);
if (!NT_STATUS_IS_OK(nt_status)) {
return ADS_ERROR_NT(nt_status);
}
ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_SIGN;
if (!NT_STATUS_IS_OK(nt_status = ntlmssp_set_username(ntlmssp_state, ads->auth.user_name))) {
return ADS_ERROR_NT(nt_status);
}
if (!NT_STATUS_IS_OK(nt_status = ntlmssp_set_domain(ntlmssp_state, ads->auth.realm))) {
return ADS_ERROR_NT(nt_status);
}
if (!NT_STATUS_IS_OK(nt_status = ntlmssp_set_password(ntlmssp_state, ads->auth.password))) {
return ADS_ERROR_NT(nt_status);
}
switch (ads->ldap.wrap_type) {
case ADS_SASLWRAP_TYPE_SEAL:
features = NTLMSSP_FEATURE_SIGN | NTLMSSP_FEATURE_SEAL;
break;
case ADS_SASLWRAP_TYPE_SIGN:
if (ads->auth.flags & ADS_AUTH_SASL_FORCE) {
features = NTLMSSP_FEATURE_SIGN;
} else {
/*
* windows servers are broken with sign only,
* so we need to use seal here too
*/
features = NTLMSSP_FEATURE_SIGN | NTLMSSP_FEATURE_SEAL;
ads->ldap.wrap_type = ADS_SASLWRAP_TYPE_SEAL;
}
break;
case ADS_SASLWRAP_TYPE_PLAIN:
break;
}
ntlmssp_want_feature(ntlmssp_state, features);
blob_in = data_blob_null;
do {
nt_status = ntlmssp_update(ntlmssp_state,
blob_in, &blob_out);
data_blob_free(&blob_in);
if ((NT_STATUS_EQUAL(nt_status, NT_STATUS_MORE_PROCESSING_REQUIRED)
|| NT_STATUS_IS_OK(nt_status))
&& blob_out.length) {
if (turn == 1) {
const char *OIDs_ntlm[] = {OID_NTLMSSP, NULL};
/* and wrap it in a SPNEGO wrapper */
msg1 = spnego_gen_negTokenInit(talloc_tos(),
OIDs_ntlm, &blob_out, NULL);
} else {
/* wrap it in SPNEGO */
msg1 = spnego_gen_auth(talloc_tos(), blob_out);
}
data_blob_free(&blob_out);
cred.bv_val = (char *)msg1.data;
cred.bv_len = msg1.length;
scred = NULL;
rc = ldap_sasl_bind_s(ads->ldap.ld, NULL, "GSS-SPNEGO", &cred, NULL, NULL, &scred);
data_blob_free(&msg1);
if ((rc != LDAP_SASL_BIND_IN_PROGRESS) && (rc != 0)) {
if (scred) {
ber_bvfree(scred);
}
TALLOC_FREE(ntlmssp_state);
return ADS_ERROR(rc);
}
if (scred) {
blob = data_blob(scred->bv_val, scred->bv_len);
ber_bvfree(scred);
} else {
blob = data_blob_null;
}
} else {
TALLOC_FREE(ntlmssp_state);
data_blob_free(&blob_out);
return ADS_ERROR_NT(nt_status);
}
if ((turn == 1) &&
(rc == LDAP_SASL_BIND_IN_PROGRESS)) {
DATA_BLOB tmp_blob = data_blob_null;
/* the server might give us back two challenges */
if (!spnego_parse_challenge(talloc_tos(), blob, &blob_in,
&tmp_blob)) {
TALLOC_FREE(ntlmssp_state);
data_blob_free(&blob);
DEBUG(3,("Failed to parse challenges\n"));
return ADS_ERROR_NT(NT_STATUS_INVALID_PARAMETER);
}
data_blob_free(&tmp_blob);
} else if (rc == LDAP_SASL_BIND_IN_PROGRESS) {
if (!spnego_parse_auth_response(talloc_tos(), blob, nt_status, OID_NTLMSSP,
&blob_in)) {
TALLOC_FREE(ntlmssp_state);
data_blob_free(&blob);
DEBUG(3,("Failed to parse auth response\n"));
return ADS_ERROR_NT(NT_STATUS_INVALID_PARAMETER);
}
}
data_blob_free(&blob);
data_blob_free(&blob_out);
turn++;
} while (rc == LDAP_SASL_BIND_IN_PROGRESS && !NT_STATUS_IS_OK(nt_status));
/* we have a reference conter on ntlmssp_state, if we are signing
then the state will be kept by the signing engine */
if (ads->ldap.wrap_type > ADS_SASLWRAP_TYPE_PLAIN) {
ads->ldap.out.max_unwrapped = ADS_SASL_WRAPPING_OUT_MAX_WRAPPED - NTLMSSP_SIG_SIZE;
ads->ldap.out.sig_size = NTLMSSP_SIG_SIZE;
ads->ldap.in.min_wrapped = ads->ldap.out.sig_size;
ads->ldap.in.max_wrapped = ADS_SASL_WRAPPING_IN_MAX_WRAPPED;
status = ads_setup_sasl_wrapping(ads, &ads_sasl_ntlmssp_ops, ntlmssp_state);
if (!ADS_ERR_OK(status)) {
DEBUG(0, ("ads_setup_sasl_wrapping() failed: %s\n",
ads_errstr(status)));
TALLOC_FREE(ntlmssp_state);
return status;
}
} else {
TALLOC_FREE(ntlmssp_state);
}
return ADS_ERROR(rc);
}
#ifdef HAVE_GSSAPI
static ADS_STATUS ads_sasl_gssapi_wrap(ADS_STRUCT *ads, uint8 *buf, uint32 len)
{
gss_ctx_id_t context_handle = (gss_ctx_id_t)ads->ldap.wrap_private_data;
ADS_STATUS status;
int gss_rc;
uint32 minor_status;
gss_buffer_desc unwrapped, wrapped;
int conf_req_flag, conf_state;
unwrapped.value = buf;
unwrapped.length = len;
/* for now request sign and seal */
conf_req_flag = (ads->ldap.wrap_type == ADS_SASLWRAP_TYPE_SEAL);
gss_rc = gss_wrap(&minor_status, context_handle,
conf_req_flag, GSS_C_QOP_DEFAULT,
&unwrapped, &conf_state,
&wrapped);
status = ADS_ERROR_GSS(gss_rc, minor_status);
if (!ADS_ERR_OK(status)) return status;
if (conf_req_flag && conf_state == 0) {
return ADS_ERROR_NT(NT_STATUS_ACCESS_DENIED);
}
if ((ads->ldap.out.size - 4) < wrapped.length) {
return ADS_ERROR_NT(NT_STATUS_INTERNAL_ERROR);
}
/* copy the wrapped blob to the right location */
memcpy(ads->ldap.out.buf + 4, wrapped.value, wrapped.length);
/* set how many bytes must be written to the underlying socket */
ads->ldap.out.left = 4 + wrapped.length;
gss_release_buffer(&minor_status, &wrapped);
return ADS_SUCCESS;
}
static ADS_STATUS ads_sasl_gssapi_unwrap(ADS_STRUCT *ads)
{
gss_ctx_id_t context_handle = (gss_ctx_id_t)ads->ldap.wrap_private_data;
ADS_STATUS status;
int gss_rc;
uint32 minor_status;
gss_buffer_desc unwrapped, wrapped;
int conf_state;
wrapped.value = ads->ldap.in.buf + 4;
wrapped.length = ads->ldap.in.ofs - 4;
gss_rc = gss_unwrap(&minor_status, context_handle,
&wrapped, &unwrapped,
&conf_state, GSS_C_QOP_DEFAULT);
status = ADS_ERROR_GSS(gss_rc, minor_status);
if (!ADS_ERR_OK(status)) return status;
if (ads->ldap.wrap_type == ADS_SASLWRAP_TYPE_SEAL && conf_state == 0) {
return ADS_ERROR_NT(NT_STATUS_ACCESS_DENIED);
}
if (wrapped.length < unwrapped.length) {
return ADS_ERROR_NT(NT_STATUS_INTERNAL_ERROR);
}
/* copy the wrapped blob to the right location */
memcpy(ads->ldap.in.buf + 4, unwrapped.value, unwrapped.length);
/* set how many bytes must be written to the underlying socket */
ads->ldap.in.left = unwrapped.length;
ads->ldap.in.ofs = 4;
gss_release_buffer(&minor_status, &unwrapped);
return ADS_SUCCESS;
}
static void ads_sasl_gssapi_disconnect(ADS_STRUCT *ads)
{
gss_ctx_id_t context_handle = (gss_ctx_id_t)ads->ldap.wrap_private_data;
uint32 minor_status;
gss_delete_sec_context(&minor_status, &context_handle, GSS_C_NO_BUFFER);
ads->ldap.wrap_ops = NULL;
ads->ldap.wrap_private_data = NULL;
}
static const struct ads_saslwrap_ops ads_sasl_gssapi_ops = {
.name = "gssapi",
.wrap = ads_sasl_gssapi_wrap,
.unwrap = ads_sasl_gssapi_unwrap,
.disconnect = ads_sasl_gssapi_disconnect
};
/*
perform a LDAP/SASL/SPNEGO/GSSKRB5 bind
*/
static ADS_STATUS ads_sasl_spnego_gsskrb5_bind(ADS_STRUCT *ads, const gss_name_t serv_name)
{
ADS_STATUS status;
bool ok;
uint32 minor_status;
int gss_rc, rc;
gss_OID_desc krb5_mech_type =
{9, CONST_DISCARD(char *, "\x2a\x86\x48\x86\xf7\x12\x01\x02\x02") };
gss_OID mech_type = &krb5_mech_type;
gss_OID actual_mech_type = GSS_C_NULL_OID;
const char *spnego_mechs[] = {OID_KERBEROS5_OLD, OID_KERBEROS5, OID_NTLMSSP, NULL};
gss_ctx_id_t context_handle = GSS_C_NO_CONTEXT;
gss_buffer_desc input_token, output_token;
uint32 req_flags, ret_flags;
uint32 req_tmp, ret_tmp;
DATA_BLOB unwrapped;
DATA_BLOB wrapped;
struct berval cred, *scred = NULL;
input_token.value = NULL;
input_token.length = 0;
req_flags = GSS_C_MUTUAL_FLAG | GSS_C_REPLAY_FLAG;
switch (ads->ldap.wrap_type) {
case ADS_SASLWRAP_TYPE_SEAL:
req_flags |= GSS_C_INTEG_FLAG | GSS_C_CONF_FLAG;
break;
case ADS_SASLWRAP_TYPE_SIGN:
req_flags |= GSS_C_INTEG_FLAG;
break;
case ADS_SASLWRAP_TYPE_PLAIN:
break;
}
/* Note: here we explicit ask for the krb5 mech_type */
gss_rc = gss_init_sec_context(&minor_status,
GSS_C_NO_CREDENTIAL,
&context_handle,
serv_name,
mech_type,
req_flags,
0,
NULL,
&input_token,
&actual_mech_type,
&output_token,
&ret_flags,
NULL);
if (gss_rc && gss_rc != GSS_S_CONTINUE_NEEDED) {
status = ADS_ERROR_GSS(gss_rc, minor_status);
goto failed;
}
/*
* As some gssapi krb5 mech implementations
* automaticly add GSS_C_INTEG_FLAG and GSS_C_CONF_FLAG
* to req_flags internaly, it's not possible to
* use plain or signing only connection via
* the gssapi interface.
*
* Because of this we need to check it the ret_flags
* has more flags as req_flags and correct the value
* of ads->ldap.wrap_type.
*
* I ads->auth.flags has ADS_AUTH_SASL_FORCE
* we need to give an error.
*/
req_tmp = req_flags & (GSS_C_INTEG_FLAG | GSS_C_CONF_FLAG);
ret_tmp = ret_flags & (GSS_C_INTEG_FLAG | GSS_C_CONF_FLAG);
if (req_tmp == ret_tmp) {
/* everythings fine... */
} else if (req_flags & GSS_C_CONF_FLAG) {
/*
* here we wanted sealing but didn't got it
* from the gssapi library
*/
status = ADS_ERROR_NT(NT_STATUS_NOT_SUPPORTED);
goto failed;
} else if ((req_flags & GSS_C_INTEG_FLAG) &&
!(ret_flags & GSS_C_INTEG_FLAG)) {
/*
* here we wanted siging but didn't got it
* from the gssapi library
*/
status = ADS_ERROR_NT(NT_STATUS_NOT_SUPPORTED);
goto failed;
} else if (ret_flags & GSS_C_CONF_FLAG) {
/*
* here we didn't want sealing
* but the gssapi library forces it
* so correct the needed wrap_type if
* the caller didn't forced siging only
*/
if (ads->auth.flags & ADS_AUTH_SASL_FORCE) {
status = ADS_ERROR_NT(NT_STATUS_NOT_SUPPORTED);
goto failed;
}
ads->ldap.wrap_type = ADS_SASLWRAP_TYPE_SEAL;
req_flags = ret_flags;
} else if (ret_flags & GSS_C_INTEG_FLAG) {
/*
* here we didn't want signing
* but the gssapi library forces it
* so correct the needed wrap_type if
* the caller didn't forced plain
*/
if (ads->auth.flags & ADS_AUTH_SASL_FORCE) {
status = ADS_ERROR_NT(NT_STATUS_NOT_SUPPORTED);
goto failed;
}
ads->ldap.wrap_type = ADS_SASLWRAP_TYPE_SIGN;
req_flags = ret_flags;
} else {
/*
* This could (should?) not happen
*/
status = ADS_ERROR_NT(NT_STATUS_INTERNAL_ERROR);
goto failed;
}
/* and wrap that in a shiny SPNEGO wrapper */
unwrapped = data_blob_const(output_token.value, output_token.length);
wrapped = spnego_gen_negTokenInit(talloc_tos(),
spnego_mechs, &unwrapped, NULL);
gss_release_buffer(&minor_status, &output_token);
if (unwrapped.length > wrapped.length) {
status = ADS_ERROR_NT(NT_STATUS_NO_MEMORY);
goto failed;
}
cred.bv_val = (char *)wrapped.data;
cred.bv_len = wrapped.length;
rc = ldap_sasl_bind_s(ads->ldap.ld, NULL, "GSS-SPNEGO", &cred, NULL, NULL,
&scred);
data_blob_free(&wrapped);
if (rc != LDAP_SUCCESS) {
status = ADS_ERROR(rc);
goto failed;
}
if (scred) {
wrapped = data_blob_const(scred->bv_val, scred->bv_len);
} else {
wrapped = data_blob_null;
}
ok = spnego_parse_auth_response(talloc_tos(), wrapped, NT_STATUS_OK,
OID_KERBEROS5_OLD,
&unwrapped);
if (scred) ber_bvfree(scred);
if (!ok) {
status = ADS_ERROR_NT(NT_STATUS_INVALID_NETWORK_RESPONSE);
goto failed;
}
input_token.value = unwrapped.data;
input_token.length = unwrapped.length;
/*
* As we asked for mutal authentication
* we need to pass the servers response
* to gssapi
*/
gss_rc = gss_init_sec_context(&minor_status,
GSS_C_NO_CREDENTIAL,
&context_handle,
serv_name,
mech_type,
req_flags,
0,
NULL,
&input_token,
&actual_mech_type,
&output_token,
&ret_flags,
NULL);
data_blob_free(&unwrapped);
if (gss_rc) {
status = ADS_ERROR_GSS(gss_rc, minor_status);
goto failed;
}
gss_release_buffer(&minor_status, &output_token);
/*
* If we the sign and seal options
* doesn't match after getting the response
* from the server, we don't want to use the connection
*/
req_tmp = req_flags & (GSS_C_INTEG_FLAG | GSS_C_CONF_FLAG);
ret_tmp = ret_flags & (GSS_C_INTEG_FLAG | GSS_C_CONF_FLAG);
if (req_tmp != ret_tmp) {
/* everythings fine... */
status = ADS_ERROR_NT(NT_STATUS_INVALID_NETWORK_RESPONSE);
goto failed;
}
if (ads->ldap.wrap_type > ADS_SASLWRAP_TYPE_PLAIN) {
uint32 max_msg_size = ADS_SASL_WRAPPING_OUT_MAX_WRAPPED;
gss_rc = gss_wrap_size_limit(&minor_status, context_handle,
(ads->ldap.wrap_type == ADS_SASLWRAP_TYPE_SEAL),
GSS_C_QOP_DEFAULT,
max_msg_size, &ads->ldap.out.max_unwrapped);
if (gss_rc) {
status = ADS_ERROR_GSS(gss_rc, minor_status);
goto failed;
}
ads->ldap.out.sig_size = max_msg_size - ads->ldap.out.max_unwrapped;
ads->ldap.in.min_wrapped = 0x2C; /* taken from a capture with LDAP unbind */
ads->ldap.in.max_wrapped = max_msg_size;
status = ads_setup_sasl_wrapping(ads, &ads_sasl_gssapi_ops, context_handle);
if (!ADS_ERR_OK(status)) {
DEBUG(0, ("ads_setup_sasl_wrapping() failed: %s\n",
ads_errstr(status)));
goto failed;
}
/* make sure we don't free context_handle */
context_handle = GSS_C_NO_CONTEXT;
}
status = ADS_SUCCESS;
failed:
if (context_handle != GSS_C_NO_CONTEXT)
gss_delete_sec_context(&minor_status, &context_handle, GSS_C_NO_BUFFER);
return status;
}
#endif /* HAVE_GSSAPI */
#ifdef HAVE_KRB5
struct ads_service_principal {
char *string;
#ifdef HAVE_GSSAPI
gss_name_t name;
#endif
};
static void ads_free_service_principal(struct ads_service_principal *p)
{
SAFE_FREE(p->string);
#ifdef HAVE_GSSAPI
if (p->name) {
uint32 minor_status;
gss_release_name(&minor_status, &p->name);
}
#endif
ZERO_STRUCTP(p);
}
static ADS_STATUS ads_generate_service_principal(ADS_STRUCT *ads,
const char *given_principal,
struct ads_service_principal *p)
{
ADS_STATUS status;
#ifdef HAVE_GSSAPI
gss_buffer_desc input_name;
/* GSS_KRB5_NT_PRINCIPAL_NAME */
gss_OID_desc nt_principal =
{10, CONST_DISCARD(char *, "\x2a\x86\x48\x86\xf7\x12\x01\x02\x02\x01")};
uint32 minor_status;
int gss_rc;
#endif
ZERO_STRUCTP(p);
/* I've seen a child Windows 2000 domain not send
the principal name back in the first round of
the SASL bind reply. So we guess based on server
name and realm. --jerry */
/* Also try best guess when we get the w2k8 ignore
principal back - gd */
if (!given_principal ||
strequal(given_principal, ADS_IGNORE_PRINCIPAL)) {
status = ads_guess_service_principal(ads, &p->string);
if (!ADS_ERR_OK(status)) {
return status;
}
} else {
p->string = SMB_STRDUP(given_principal);
if (!p->string) {
return ADS_ERROR(LDAP_NO_MEMORY);
}
}
#ifdef HAVE_GSSAPI
input_name.value = p->string;
input_name.length = strlen(p->string);
gss_rc = gss_import_name(&minor_status, &input_name, &nt_principal, &p->name);
if (gss_rc) {
ads_free_service_principal(p);
return ADS_ERROR_GSS(gss_rc, minor_status);
}
#endif
return ADS_SUCCESS;
}
/*
perform a LDAP/SASL/SPNEGO/KRB5 bind
*/
static ADS_STATUS ads_sasl_spnego_rawkrb5_bind(ADS_STRUCT *ads, const char *principal)
{
DATA_BLOB blob = data_blob_null;
struct berval cred, *scred = NULL;
DATA_BLOB session_key = data_blob_null;
int rc;
if (ads->ldap.wrap_type > ADS_SASLWRAP_TYPE_PLAIN) {
return ADS_ERROR_NT(NT_STATUS_NOT_SUPPORTED);
}
rc = spnego_gen_krb5_negTokenInit(talloc_tos(), principal,
ads->auth.time_offset, &blob, &session_key, 0,
&ads->auth.tgs_expire);
if (rc) {
return ADS_ERROR_KRB5(rc);
}
/* now send the auth packet and we should be done */
cred.bv_val = (char *)blob.data;
cred.bv_len = blob.length;
rc = ldap_sasl_bind_s(ads->ldap.ld, NULL, "GSS-SPNEGO", &cred, NULL, NULL, &scred);
data_blob_free(&blob);
data_blob_free(&session_key);
if(scred)
ber_bvfree(scred);
return ADS_ERROR(rc);
}
static ADS_STATUS ads_sasl_spnego_krb5_bind(ADS_STRUCT *ads,
struct ads_service_principal *p)
{
#ifdef HAVE_GSSAPI
/*
* we only use the gsskrb5 based implementation
* when sasl sign or seal is requested.
*
* This has the following reasons:
* - it's likely that the gssapi krb5 mech implementation
* doesn't support to negotiate plain connections
* - the ads_sasl_spnego_rawkrb5_bind is more robust
* against clock skew errors
*/
if (ads->ldap.wrap_type > ADS_SASLWRAP_TYPE_PLAIN) {
return ads_sasl_spnego_gsskrb5_bind(ads, p->name);
}
#endif
return ads_sasl_spnego_rawkrb5_bind(ads, p->string);
}
#endif /* HAVE_KRB5 */
/*
this performs a SASL/SPNEGO bind
*/
static ADS_STATUS ads_sasl_spnego_bind(ADS_STRUCT *ads)
{
struct berval *scred=NULL;
int rc, i;
ADS_STATUS status;
DATA_BLOB blob;
char *given_principal = NULL;
char *OIDs[ASN1_MAX_OIDS];
#ifdef HAVE_KRB5
bool got_kerberos_mechanism = False;
#endif
rc = ldap_sasl_bind_s(ads->ldap.ld, NULL, "GSS-SPNEGO", NULL, NULL, NULL, &scred);
if (rc != LDAP_SASL_BIND_IN_PROGRESS) {
status = ADS_ERROR(rc);
goto failed;
}
blob = data_blob(scred->bv_val, scred->bv_len);
ber_bvfree(scred);
#if 0
file_save("sasl_spnego.dat", blob.data, blob.length);
#endif
/* the server sent us the first part of the SPNEGO exchange in the negprot
reply */
if (!spnego_parse_negTokenInit(talloc_tos(), blob, OIDs, &given_principal, NULL)) {
data_blob_free(&blob);
status = ADS_ERROR(LDAP_OPERATIONS_ERROR);
goto failed;
}
data_blob_free(&blob);
/* make sure the server understands kerberos */
for (i=0;OIDs[i];i++) {
DEBUG(3,("ads_sasl_spnego_bind: got OID=%s\n", OIDs[i]));
#ifdef HAVE_KRB5
if (strcmp(OIDs[i], OID_KERBEROS5_OLD) == 0 ||
strcmp(OIDs[i], OID_KERBEROS5) == 0) {
got_kerberos_mechanism = True;
}
#endif
talloc_free(OIDs[i]);
}
DEBUG(3,("ads_sasl_spnego_bind: got server principal name = %s\n", given_principal));
#ifdef HAVE_KRB5
if (!(ads->auth.flags & ADS_AUTH_DISABLE_KERBEROS) &&
got_kerberos_mechanism)
{
struct ads_service_principal p;
status = ads_generate_service_principal(ads, given_principal, &p);
TALLOC_FREE(given_principal);
if (!ADS_ERR_OK(status)) {
return status;
}
status = ads_sasl_spnego_krb5_bind(ads, &p);
if (ADS_ERR_OK(status)) {
ads_free_service_principal(&p);
return status;
}
DEBUG(10,("ads_sasl_spnego_krb5_bind failed with: %s, "
"calling kinit\n", ads_errstr(status)));
status = ADS_ERROR_KRB5(ads_kinit_password(ads));
if (ADS_ERR_OK(status)) {
status = ads_sasl_spnego_krb5_bind(ads, &p);
if (!ADS_ERR_OK(status)) {
DEBUG(0,("kinit succeeded but "
"ads_sasl_spnego_krb5_bind failed: %s\n",
ads_errstr(status)));
}
}
ads_free_service_principal(&p);
/* only fallback to NTLMSSP if allowed */
if (ADS_ERR_OK(status) ||
!(ads->auth.flags & ADS_AUTH_ALLOW_NTLMSSP)) {
return status;
}
} else
#endif
{
TALLOC_FREE(given_principal);
}
/* lets do NTLMSSP ... this has the big advantage that we don't need
to sync clocks, and we don't rely on special versions of the krb5
library for HMAC_MD4 encryption */
return ads_sasl_spnego_ntlmssp_bind(ads);
failed:
return status;
}
#ifdef HAVE_GSSAPI
#define MAX_GSS_PASSES 3
/* this performs a SASL/gssapi bind
we avoid using cyrus-sasl to make Samba more robust. cyrus-sasl
is very dependent on correctly configured DNS whereas
this routine is much less fragile
see RFC2078 and RFC2222 for details
*/
static ADS_STATUS ads_sasl_gssapi_do_bind(ADS_STRUCT *ads, const gss_name_t serv_name)
{
uint32 minor_status;
gss_ctx_id_t context_handle = GSS_C_NO_CONTEXT;
gss_OID mech_type = GSS_C_NULL_OID;
gss_buffer_desc output_token, input_token;
uint32 req_flags, ret_flags;
int conf_state;
struct berval cred;
struct berval *scred = NULL;
int i=0;
int gss_rc, rc;
uint8 *p;
uint32 max_msg_size = ADS_SASL_WRAPPING_OUT_MAX_WRAPPED;
uint8 wrap_type = ADS_SASLWRAP_TYPE_PLAIN;
ADS_STATUS status;
input_token.value = NULL;
input_token.length = 0;
/*
* Note: here we always ask the gssapi for sign and seal
* as this is negotiated later after the mutal
* authentication
*/
req_flags = GSS_C_MUTUAL_FLAG | GSS_C_REPLAY_FLAG | GSS_C_INTEG_FLAG | GSS_C_CONF_FLAG;
for (i=0; i < MAX_GSS_PASSES; i++) {
gss_rc = gss_init_sec_context(&minor_status,
GSS_C_NO_CREDENTIAL,
&context_handle,
serv_name,
mech_type,
req_flags,
0,
NULL,
&input_token,
NULL,
&output_token,
&ret_flags,
NULL);
if (scred) {
ber_bvfree(scred);
scred = NULL;
}
if (gss_rc && gss_rc != GSS_S_CONTINUE_NEEDED) {
status = ADS_ERROR_GSS(gss_rc, minor_status);
goto failed;
}
cred.bv_val = (char *)output_token.value;
cred.bv_len = output_token.length;
rc = ldap_sasl_bind_s(ads->ldap.ld, NULL, "GSSAPI", &cred, NULL, NULL,
&scred);
if (rc != LDAP_SASL_BIND_IN_PROGRESS) {
status = ADS_ERROR(rc);
goto failed;
}
if (output_token.value) {
gss_release_buffer(&minor_status, &output_token);
}
if (scred) {
input_token.value = scred->bv_val;
input_token.length = scred->bv_len;
} else {
input_token.value = NULL;
input_token.length = 0;
}
if (gss_rc == 0) break;
}
gss_rc = gss_unwrap(&minor_status,context_handle,&input_token,&output_token,
&conf_state,NULL);
if (scred) {
ber_bvfree(scred);
scred = NULL;
}
if (gss_rc) {
status = ADS_ERROR_GSS(gss_rc, minor_status);
goto failed;
}
p = (uint8 *)output_token.value;
#if 0
file_save("sasl_gssapi.dat", output_token.value, output_token.length);
#endif
if (p) {
wrap_type = CVAL(p,0);
SCVAL(p,0,0);
max_msg_size = RIVAL(p,0);
}
gss_release_buffer(&minor_status, &output_token);
if (!(wrap_type & ads->ldap.wrap_type)) {
/*
* the server doesn't supports the wrap
* type we want :-(
*/
DEBUG(0,("The ldap sasl wrap type doesn't match wanted[%d] server[%d]\n",
ads->ldap.wrap_type, wrap_type));
DEBUGADD(0,("You may want to set the 'client ldap sasl wrapping' option\n"));
status = ADS_ERROR_NT(NT_STATUS_NOT_SUPPORTED);
goto failed;
}
/* 0x58 is the minimum windows accepts */
if (max_msg_size < 0x58) {
max_msg_size = 0x58;
}
output_token.length = 4;
output_token.value = SMB_MALLOC(output_token.length);
p = (uint8 *)output_token.value;
RSIVAL(p,0,max_msg_size);
SCVAL(p,0,ads->ldap.wrap_type);
/*
* we used to add sprintf("dn:%s", ads->config.bind_path) here.
* but using ads->config.bind_path is the wrong! It should be
* the DN of the user object!
*
* w2k3 gives an error when we send an incorrect DN, but sending nothing
* is ok and matches the information flow used in GSS-SPNEGO.
*/
gss_rc = gss_wrap(&minor_status, context_handle,0,GSS_C_QOP_DEFAULT,
&output_token, &conf_state,
&input_token);
if (gss_rc) {
status = ADS_ERROR_GSS(gss_rc, minor_status);
goto failed;
}
free(output_token.value);
cred.bv_val = (char *)input_token.value;
cred.bv_len = input_token.length;
rc = ldap_sasl_bind_s(ads->ldap.ld, NULL, "GSSAPI", &cred, NULL, NULL,
&scred);
gss_release_buffer(&minor_status, &input_token);
status = ADS_ERROR(rc);
if (!ADS_ERR_OK(status)) {
goto failed;
}
if (ads->ldap.wrap_type > ADS_SASLWRAP_TYPE_PLAIN) {
gss_rc = gss_wrap_size_limit(&minor_status, context_handle,
(ads->ldap.wrap_type == ADS_SASLWRAP_TYPE_SEAL),
GSS_C_QOP_DEFAULT,
max_msg_size, &ads->ldap.out.max_unwrapped);
if (gss_rc) {
status = ADS_ERROR_GSS(gss_rc, minor_status);
goto failed;
}
ads->ldap.out.sig_size = max_msg_size - ads->ldap.out.max_unwrapped;
ads->ldap.in.min_wrapped = 0x2C; /* taken from a capture with LDAP unbind */
ads->ldap.in.max_wrapped = max_msg_size;
status = ads_setup_sasl_wrapping(ads, &ads_sasl_gssapi_ops, context_handle);
if (!ADS_ERR_OK(status)) {
DEBUG(0, ("ads_setup_sasl_wrapping() failed: %s\n",
ads_errstr(status)));
goto failed;
}
/* make sure we don't free context_handle */
context_handle = GSS_C_NO_CONTEXT;
}
failed:
if (context_handle != GSS_C_NO_CONTEXT)
gss_delete_sec_context(&minor_status, &context_handle, GSS_C_NO_BUFFER);
if(scred)
ber_bvfree(scred);
return status;
}
static ADS_STATUS ads_sasl_gssapi_bind(ADS_STRUCT *ads)
{
ADS_STATUS status;
struct ads_service_principal p;
status = ads_generate_service_principal(ads, NULL, &p);
if (!ADS_ERR_OK(status)) {
return status;
}
status = ads_sasl_gssapi_do_bind(ads, p.name);
if (ADS_ERR_OK(status)) {
ads_free_service_principal(&p);
return status;
}
DEBUG(10,("ads_sasl_gssapi_do_bind failed with: %s, "
"calling kinit\n", ads_errstr(status)));
status = ADS_ERROR_KRB5(ads_kinit_password(ads));
if (ADS_ERR_OK(status)) {
status = ads_sasl_gssapi_do_bind(ads, p.name);
}
ads_free_service_principal(&p);
return status;
}
#endif /* HAVE_GSSAPI */
/* mapping between SASL mechanisms and functions */
static struct {
const char *name;
ADS_STATUS (*fn)(ADS_STRUCT *);
} sasl_mechanisms[] = {
{"GSS-SPNEGO", ads_sasl_spnego_bind},
#ifdef HAVE_GSSAPI
{"GSSAPI", ads_sasl_gssapi_bind}, /* doesn't work with .NET RC1. No idea why */
#endif
{NULL, NULL}
};
ADS_STATUS ads_sasl_bind(ADS_STRUCT *ads)
{
const char *attrs[] = {"supportedSASLMechanisms", NULL};
char **values;
ADS_STATUS status;
int i, j;
LDAPMessage *res;
/* get a list of supported SASL mechanisms */
status = ads_do_search(ads, "", LDAP_SCOPE_BASE, "(objectclass=*)", attrs, &res);
if (!ADS_ERR_OK(status)) return status;
values = ldap_get_values(ads->ldap.ld, res, "supportedSASLMechanisms");
if (ads->auth.flags & ADS_AUTH_SASL_SEAL) {
ads->ldap.wrap_type = ADS_SASLWRAP_TYPE_SEAL;
} else if (ads->auth.flags & ADS_AUTH_SASL_SIGN) {
ads->ldap.wrap_type = ADS_SASLWRAP_TYPE_SIGN;
} else {
ads->ldap.wrap_type = ADS_SASLWRAP_TYPE_PLAIN;
}
/* try our supported mechanisms in order */
for (i=0;sasl_mechanisms[i].name;i++) {
/* see if the server supports it */
for (j=0;values && values[j];j++) {
if (strcmp(values[j], sasl_mechanisms[i].name) == 0) {
DEBUG(4,("Found SASL mechanism %s\n", values[j]));
retry:
status = sasl_mechanisms[i].fn(ads);
if (status.error_type == ENUM_ADS_ERROR_LDAP &&
status.err.rc == LDAP_STRONG_AUTH_REQUIRED &&
ads->ldap.wrap_type == ADS_SASLWRAP_TYPE_PLAIN)
{
DEBUG(3,("SASL bin got LDAP_STRONG_AUTH_REQUIRED "
"retrying with signing enabled\n"));
ads->ldap.wrap_type = ADS_SASLWRAP_TYPE_SIGN;
goto retry;
}
ldap_value_free(values);
ldap_msgfree(res);
return status;
}
}
}
ldap_value_free(values);
ldap_msgfree(res);
return ADS_ERROR(LDAP_AUTH_METHOD_NOT_SUPPORTED);
}
#endif /* HAVE_LDAP */