/*
perform a sasl bind using the given credentials
*/
_PUBLIC_ NTSTATUS ldap_bind_sasl(struct ldap_connection *conn,
struct cli_credentials *creds,
struct loadparm_context *lp_ctx)
{
NTSTATUS status;
TALLOC_CTX *tmp_ctx = NULL;
DATA_BLOB input = data_blob(NULL, 0);
DATA_BLOB output = data_blob(NULL, 0);
struct ldap_message **sasl_mechs_msgs;
struct ldap_SearchResEntry *search;
int count, i;
const char **sasl_names;
uint32_t old_gensec_features;
static const char *supported_sasl_mech_attrs[] = {
"supportedSASLMechanisms",
NULL
};
unsigned int logon_retries = 0;
status = ildap_search(conn, "", LDAP_SEARCH_SCOPE_BASE, "", supported_sasl_mech_attrs,
false, NULL, NULL, &sasl_mechs_msgs);
if (!NT_STATUS_IS_OK(status)) {
DEBUG(1, ("Failed to inquire of target's available sasl mechs in rootdse search: %s\n",
nt_errstr(status)));
goto failed;
}
count = ildap_count_entries(conn, sasl_mechs_msgs);
if (count != 1) {
DEBUG(1, ("Failed to inquire of target's available sasl mechs in rootdse search: wrong number of replies: %d\n",
count));
goto failed;
}
tmp_ctx = talloc_new(conn);
if (tmp_ctx == NULL) goto failed;
search = &sasl_mechs_msgs[0]->r.SearchResultEntry;
if (search->num_attributes != 1) {
DEBUG(1, ("Failed to inquire of target's available sasl mechs in rootdse search: wrong number of attributes: %d != 1\n",
search->num_attributes));
goto failed;
}
sasl_names = talloc_array(tmp_ctx, const char *, search->attributes[0].num_values + 1);
if (!sasl_names) {
DEBUG(1, ("talloc_arry(char *, %d) failed\n",
count));
goto failed;
}
for (i=0; i<search->attributes[0].num_values; i++) {
sasl_names[i] = (const char *)search->attributes[0].values[i].data;
}
sasl_names[i] = NULL;
gensec_init();
try_logon_again:
/*
we loop back here on a logon failure, and re-create the
gensec session. The logon_retries counter ensures we don't
loop forever.
*/
status = gensec_client_start(conn, &conn->gensec,
lpcfg_gensec_settings(conn, lp_ctx));
if (!NT_STATUS_IS_OK(status)) {
DEBUG(0, ("Failed to start GENSEC engine (%s)\n", nt_errstr(status)));
goto failed;
}
/* require Kerberos SIGN/SEAL only if we don't use SSL
* Windows seem not to like double encryption */
old_gensec_features = cli_credentials_get_gensec_features(creds);
if (tls_enabled(conn->sock)) {
cli_credentials_set_gensec_features(creds, old_gensec_features & ~(GENSEC_FEATURE_SIGN|GENSEC_FEATURE_SEAL));
}
/* this call also sets the gensec_want_features */
status = gensec_set_credentials(conn->gensec, creds);
if (!NT_STATUS_IS_OK(status)) {
DEBUG(1, ("Failed to set GENSEC creds: %s\n",
nt_errstr(status)));
goto failed;
}
/* reset the original gensec_features (on the credentials
* context, so we don't tatoo it ) */
cli_credentials_set_gensec_features(creds, old_gensec_features);
if (conn->host) {
status = gensec_set_target_hostname(conn->gensec, conn->host);
if (!NT_STATUS_IS_OK(status)) {
DEBUG(1, ("Failed to set GENSEC target hostname: %s\n",
nt_errstr(status)));
goto failed;
}
}
status = gensec_set_target_service(conn->gensec, "ldap");
if (!NT_STATUS_IS_OK(status)) {
DEBUG(1, ("Failed to set GENSEC target service: %s\n",
nt_errstr(status)));
goto failed;
}
status = gensec_start_mech_by_sasl_list(conn->gensec, sasl_names);
if (!NT_STATUS_IS_OK(status)) {
DEBUG(1, ("None of the %d proposed SASL mechs were acceptable: %s\n",
count, nt_errstr(status)));
goto failed;
}
while (1) {
NTSTATUS gensec_status;
struct ldap_message *response;
struct ldap_message *msg;
struct ldap_request *req;
int result = LDAP_OTHER;
status = gensec_update(conn->gensec, tmp_ctx,
conn->event.event_ctx,
input,
&output);
/* The status value here, from GENSEC is vital to the security
* of the system. Even if the other end accepts, if GENSEC
* claims 'MORE_PROCESSING_REQUIRED' then you must keep
* feeding it blobs, or else the remote host/attacker might
* avoid mutal authentication requirements.
*
* Likewise, you must not feed GENSEC too much (after the OK),
* it doesn't like that either
*/
gensec_status = status;
if (!NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED) &&
!NT_STATUS_IS_OK(status)) {
break;
}
if (NT_STATUS_IS_OK(status) && output.length == 0) {
break;
}
/* Perhaps we should make gensec_start_mech_by_sasl_list() return the name we got? */
msg = new_ldap_sasl_bind_msg(tmp_ctx, conn->gensec->ops->sasl_name, (output.data?&output:NULL));
if (msg == NULL) {
status = NT_STATUS_NO_MEMORY;
goto failed;
}
req = ldap_request_send(conn, msg);
if (req == NULL) {
status = NT_STATUS_NO_MEMORY;
goto failed;
}
talloc_reparent(conn, tmp_ctx, req);
status = ldap_result_n(req, 0, &response);
if (!NT_STATUS_IS_OK(status)) {
goto failed;
}
if (response->type != LDAP_TAG_BindResponse) {
status = NT_STATUS_UNEXPECTED_NETWORK_ERROR;
goto failed;
}
result = response->r.BindResponse.response.resultcode;
if (result == LDAP_INVALID_CREDENTIALS) {
/*
try a second time on invalid credentials, to
give the user a chance to re-enter the
password and to handle the case where our
kerberos ticket is invalid as the server
password has changed
*/
const char *principal;
principal = gensec_get_target_principal(conn->gensec);
if (principal == NULL) {
const char *hostname = gensec_get_target_hostname(conn->gensec);
const char *service = gensec_get_target_service(conn->gensec);
if (hostname != NULL && service != NULL) {
principal = talloc_asprintf(tmp_ctx, "%s/%s", service, hostname);
}
}
if (cli_credentials_failed_kerberos_login(creds, principal, &logon_retries) ||
cli_credentials_wrong_password(creds)) {
/*
destroy our gensec session and loop
back up to the top to retry,
offering the user a chance to enter
new credentials, or get a new ticket
if using kerberos
*/
talloc_free(conn->gensec);
conn->gensec = NULL;
goto try_logon_again;
}
}
if (result != LDAP_SUCCESS && result != LDAP_SASL_BIND_IN_PROGRESS) {
status = ldap_check_response(conn,
&response->r.BindResponse.response);
break;
}
/* This is where we check if GENSEC wanted to be fed more data */
if (!NT_STATUS_EQUAL(gensec_status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
break;
}
if (response->r.BindResponse.SASL.secblob) {
input = *response->r.BindResponse.SASL.secblob;
} else {
input = data_blob(NULL, 0);
}
}
talloc_free(tmp_ctx);
if (NT_STATUS_IS_OK(status)) {
struct socket_context *sasl_socket;
status = gensec_socket_init(conn->gensec,
conn,
conn->sock,
conn->event.event_ctx,
ldap_read_io_handler,
conn,
&sasl_socket);
if (!NT_STATUS_IS_OK(status)) goto failed;
conn->sock = sasl_socket;
packet_set_socket(conn->packet, conn->sock);
conn->bind.type = LDAP_BIND_SASL;
conn->bind.creds = creds;
}
return status;
failed:
talloc_free(tmp_ctx);
talloc_free(conn->gensec);
conn->gensec = NULL;
return status;
}
/*
perform a sasl bind using the given credentials
*/
_PUBLIC_ NTSTATUS ldap_bind_sasl(struct ldap_connection *conn,
struct cli_credentials *creds,
struct loadparm_context *lp_ctx)
{
NTSTATUS status;
TALLOC_CTX *tmp_ctx = NULL;
DATA_BLOB input = data_blob(NULL, 0);
DATA_BLOB output = data_blob(NULL, 0);
struct ldap_message **sasl_mechs_msgs;
struct ldap_SearchResEntry *search;
int count, i;
bool first = true;
int wrap_flags = 0;
const char **sasl_names;
uint32_t old_gensec_features;
static const char *supported_sasl_mech_attrs[] = {
"supportedSASLMechanisms",
NULL
};
unsigned int logon_retries = 0;
size_t queue_length;
if (conn->sockets.active == NULL) {
status = NT_STATUS_CONNECTION_DISCONNECTED;
goto failed;
}
queue_length = tevent_queue_length(conn->sockets.send_queue);
if (queue_length != 0) {
status = NT_STATUS_INVALID_PARAMETER_MIX;
DEBUG(1, ("SASL bind triggered with non empty send_queue[%zu]: %s\n",
queue_length, nt_errstr(status)));
goto failed;
}
if (conn->pending != NULL) {
status = NT_STATUS_INVALID_PARAMETER_MIX;
DEBUG(1, ("SASL bind triggered with pending requests: %s\n",
nt_errstr(status)));
goto failed;
}
status = ildap_search(conn, "", LDAP_SEARCH_SCOPE_BASE, "", supported_sasl_mech_attrs,
false, NULL, NULL, &sasl_mechs_msgs);
if (!NT_STATUS_IS_OK(status)) {
DEBUG(1, ("Failed to inquire of target's available sasl mechs in rootdse search: %s\n",
nt_errstr(status)));
goto failed;
}
count = ildap_count_entries(conn, sasl_mechs_msgs);
if (count != 1) {
DEBUG(1, ("Failed to inquire of target's available sasl mechs in rootdse search: wrong number of replies: %d\n",
count));
goto failed;
}
tmp_ctx = talloc_new(conn);
if (tmp_ctx == NULL) goto failed;
search = &sasl_mechs_msgs[0]->r.SearchResultEntry;
if (search->num_attributes != 1) {
DEBUG(1, ("Failed to inquire of target's available sasl mechs in rootdse search: wrong number of attributes: %d != 1\n",
search->num_attributes));
goto failed;
}
sasl_names = talloc_array(tmp_ctx, const char *, search->attributes[0].num_values + 1);
if (!sasl_names) {
DEBUG(1, ("talloc_arry(char *, %d) failed\n",
count));
goto failed;
}
for (i=0; i<search->attributes[0].num_values; i++) {
sasl_names[i] = (const char *)search->attributes[0].values[i].data;
}
sasl_names[i] = NULL;
gensec_init();
if (conn->sockets.active == conn->sockets.tls) {
/*
* require Kerberos SIGN/SEAL only if we don't use SSL
* Windows seem not to like double encryption
*/
wrap_flags = 0;
} else if (cli_credentials_is_anonymous(creds)) {
/*
* anonymous isn't protected
*/
wrap_flags = 0;
} else {
wrap_flags = lpcfg_client_ldap_sasl_wrapping(lp_ctx);
}
try_logon_again:
/*
we loop back here on a logon failure, and re-create the
gensec session. The logon_retries counter ensures we don't
loop forever.
*/
data_blob_free(&input);
TALLOC_FREE(conn->gensec);
status = gensec_client_start(conn, &conn->gensec,
lpcfg_gensec_settings(conn, lp_ctx));
if (!NT_STATUS_IS_OK(status)) {
DEBUG(0, ("Failed to start GENSEC engine (%s)\n", nt_errstr(status)));
goto failed;
}
old_gensec_features = cli_credentials_get_gensec_features(creds);
if (wrap_flags == 0) {
cli_credentials_set_gensec_features(creds, old_gensec_features & ~(GENSEC_FEATURE_SIGN|GENSEC_FEATURE_SEAL));
}
/* this call also sets the gensec_want_features */
status = gensec_set_credentials(conn->gensec, creds);
if (!NT_STATUS_IS_OK(status)) {
DEBUG(1, ("Failed to set GENSEC creds: %s\n",
nt_errstr(status)));
goto failed;
}
/* reset the original gensec_features (on the credentials
* context, so we don't tatoo it ) */
cli_credentials_set_gensec_features(creds, old_gensec_features);
if (wrap_flags & ADS_AUTH_SASL_SEAL) {
gensec_want_feature(conn->gensec, GENSEC_FEATURE_SIGN);
gensec_want_feature(conn->gensec, GENSEC_FEATURE_SEAL);
}
if (wrap_flags & ADS_AUTH_SASL_SIGN) {
gensec_want_feature(conn->gensec, GENSEC_FEATURE_SIGN);
}
/*
* This is an indication for the NTLMSSP backend to
* also encrypt when only GENSEC_FEATURE_SIGN is requested
* in gensec_[un]wrap().
*/
gensec_want_feature(conn->gensec, GENSEC_FEATURE_LDAP_STYLE);
if (conn->host) {
status = gensec_set_target_hostname(conn->gensec, conn->host);
if (!NT_STATUS_IS_OK(status)) {
DEBUG(1, ("Failed to set GENSEC target hostname: %s\n",
nt_errstr(status)));
goto failed;
}
}
status = gensec_set_target_service(conn->gensec, "ldap");
if (!NT_STATUS_IS_OK(status)) {
DEBUG(1, ("Failed to set GENSEC target service: %s\n",
nt_errstr(status)));
goto failed;
}
status = gensec_start_mech_by_sasl_list(conn->gensec, sasl_names);
if (!NT_STATUS_IS_OK(status)) {
DEBUG(1, ("None of the %d proposed SASL mechs were acceptable: %s\n",
count, nt_errstr(status)));
goto failed;
}
while (1) {
NTSTATUS gensec_status;
struct ldap_message *response;
struct ldap_message *msg;
struct ldap_request *req;
int result = LDAP_OTHER;
status = gensec_update_ev(conn->gensec, tmp_ctx,
conn->event.event_ctx,
input,
&output);
/* The status value here, from GENSEC is vital to the security
* of the system. Even if the other end accepts, if GENSEC
* claims 'MORE_PROCESSING_REQUIRED' then you must keep
* feeding it blobs, or else the remote host/attacker might
* avoid mutal authentication requirements.
*
* Likewise, you must not feed GENSEC too much (after the OK),
* it doesn't like that either.
*
* For SASL/EXTERNAL, there is no data to send, but we still
* must send the actual Bind request the first time around.
* Otherwise, a result of NT_STATUS_OK with 0 output means the
* end of a multi-step authentication, and no message must be
* sent.
*/
gensec_status = status;
if (!NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED) &&
!NT_STATUS_IS_OK(status)) {
break;
}
if (NT_STATUS_IS_OK(status) && output.length == 0) {
if (!first)
break;
}
first = false;
/* Perhaps we should make gensec_start_mech_by_sasl_list() return the name we got? */
msg = new_ldap_sasl_bind_msg(tmp_ctx, conn->gensec->ops->sasl_name, (output.data?&output:NULL));
if (msg == NULL) {
status = NT_STATUS_NO_MEMORY;
goto failed;
}
req = ldap_request_send(conn, msg);
if (req == NULL) {
status = NT_STATUS_NO_MEMORY;
goto failed;
}
talloc_reparent(conn, tmp_ctx, req);
status = ldap_result_n(req, 0, &response);
if (!NT_STATUS_IS_OK(status)) {
goto failed;
}
if (response->type != LDAP_TAG_BindResponse) {
status = NT_STATUS_UNEXPECTED_NETWORK_ERROR;
goto failed;
}
result = response->r.BindResponse.response.resultcode;
if (result == LDAP_STRONG_AUTH_REQUIRED) {
if (wrap_flags == 0) {
wrap_flags = ADS_AUTH_SASL_SIGN;
goto try_logon_again;
}
}
if (result == LDAP_INVALID_CREDENTIALS) {
/*
try a second time on invalid credentials, to
give the user a chance to re-enter the
password and to handle the case where our
kerberos ticket is invalid as the server
password has changed
*/
const char *principal;
principal = gensec_get_target_principal(conn->gensec);
if (principal == NULL) {
const char *hostname = gensec_get_target_hostname(conn->gensec);
const char *service = gensec_get_target_service(conn->gensec);
if (hostname != NULL && service != NULL) {
principal = talloc_asprintf(tmp_ctx, "%s/%s", service, hostname);
}
}
if (cli_credentials_failed_kerberos_login(creds, principal, &logon_retries) ||
cli_credentials_wrong_password(creds)) {
/*
destroy our gensec session and loop
back up to the top to retry,
offering the user a chance to enter
new credentials, or get a new ticket
if using kerberos
*/
goto try_logon_again;
}
}
if (result != LDAP_SUCCESS && result != LDAP_SASL_BIND_IN_PROGRESS) {
status = ldap_check_response(conn,
&response->r.BindResponse.response);
break;
}
/* This is where we check if GENSEC wanted to be fed more data */
if (!NT_STATUS_EQUAL(gensec_status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
break;
}
if (response->r.BindResponse.SASL.secblob) {
input = *response->r.BindResponse.SASL.secblob;
} else {
input = data_blob(NULL, 0);
}
}
TALLOC_FREE(tmp_ctx);
if (!NT_STATUS_IS_OK(status)) {
goto failed;
}
conn->bind.type = LDAP_BIND_SASL;
conn->bind.creds = creds;
if (wrap_flags & ADS_AUTH_SASL_SEAL) {
if (!gensec_have_feature(conn->gensec, GENSEC_FEATURE_SIGN)) {
return NT_STATUS_INVALID_NETWORK_RESPONSE;
}
if (!gensec_have_feature(conn->gensec, GENSEC_FEATURE_SEAL)) {
return NT_STATUS_INVALID_NETWORK_RESPONSE;
}
} else if (wrap_flags & ADS_AUTH_SASL_SIGN) {
if (!gensec_have_feature(conn->gensec, GENSEC_FEATURE_SIGN)) {
return NT_STATUS_INVALID_NETWORK_RESPONSE;
}
}
if (!gensec_have_feature(conn->gensec, GENSEC_FEATURE_SIGN) &&
!gensec_have_feature(conn->gensec, GENSEC_FEATURE_SEAL)) {
return NT_STATUS_OK;
}
status = gensec_create_tstream(conn->sockets.raw,
conn->gensec,
conn->sockets.raw,
&conn->sockets.sasl);
if (!NT_STATUS_IS_OK(status)) {
goto failed;
}
conn->sockets.active = conn->sockets.sasl;
return NT_STATUS_OK;
failed:
talloc_free(tmp_ctx);
talloc_free(conn->gensec);
conn->gensec = NULL;
return status;
}
