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mirror of https://github.com/samba-team/samba.git synced 2025-01-15 23:24:37 +03:00
Andrew Bartlett ba90b652d9 r9505: Work on GENSEC and the code that calls it, for tighter interface
requirements, and for better error reporting.

In particular, the composite session setup (extended security/SPNEGO)
code now returns errors, rather than NT_STATUS_NO_MEMORY.  This is
seen particularly when GENSEC fails to start.

The tighter interface rules apply to NTLMSSP, which must be called
exactly the right number of times.  This is to match some of our other
less-tested modules, where adding flexablity is harder.  (and this is
security code, so let's just get it right).  As such, the DCE/RPC and
LDAP clients have been updated.

Andrew Bartlett
(This used to be commit 134550cf752b9edad66c3368750bfb4bbd9d55d1)
2007-10-10 13:34:24 -05:00

394 lines
12 KiB
C

/*
Unix SMB/Netbios implementation.
Version 3.0
handle NLTMSSP, client server side parsing
Copyright (C) Andrew Tridgell 2001
Copyright (C) Andrew Bartlett <abartlet@samba.org> 2001-2005
Copyright (C) Stefan Metzmacher 2005
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 2 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, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include "includes.h"
#include "auth/auth.h"
#include "lib/crypto/crypto.h"
#include "auth/ntlmssp/ntlmssp.h"
/**
* Callbacks for NTLMSSP - for both client and server operating modes
*
*/
static const struct ntlmssp_callbacks {
enum ntlmssp_role role;
enum ntlmssp_message_type ntlmssp_command;
NTSTATUS (*fn)(struct gensec_security *gensec_security,
TALLOC_CTX *out_mem_ctx,
DATA_BLOB in, DATA_BLOB *out);
} ntlmssp_callbacks[] = {
{NTLMSSP_CLIENT, NTLMSSP_INITIAL, ntlmssp_client_initial},
{NTLMSSP_SERVER, NTLMSSP_NEGOTIATE, ntlmssp_server_negotiate},
{NTLMSSP_CLIENT, NTLMSSP_CHALLENGE, ntlmssp_client_challenge},
{NTLMSSP_SERVER, NTLMSSP_AUTH, ntlmssp_server_auth},
};
/**
* Print out the NTLMSSP flags for debugging
* @param neg_flags The flags from the packet
*/
void debug_ntlmssp_flags(uint32_t neg_flags)
{
DEBUG(3,("Got NTLMSSP neg_flags=0x%08x\n", neg_flags));
if (neg_flags & NTLMSSP_NEGOTIATE_UNICODE)
DEBUGADD(4, (" NTLMSSP_NEGOTIATE_UNICODE\n"));
if (neg_flags & NTLMSSP_NEGOTIATE_OEM)
DEBUGADD(4, (" NTLMSSP_NEGOTIATE_OEM\n"));
if (neg_flags & NTLMSSP_REQUEST_TARGET)
DEBUGADD(4, (" NTLMSSP_REQUEST_TARGET\n"));
if (neg_flags & NTLMSSP_NEGOTIATE_SIGN)
DEBUGADD(4, (" NTLMSSP_NEGOTIATE_SIGN\n"));
if (neg_flags & NTLMSSP_NEGOTIATE_SEAL)
DEBUGADD(4, (" NTLMSSP_NEGOTIATE_SEAL\n"));
if (neg_flags & NTLMSSP_NEGOTIATE_LM_KEY)
DEBUGADD(4, (" NTLMSSP_NEGOTIATE_LM_KEY\n"));
if (neg_flags & NTLMSSP_NEGOTIATE_NETWARE)
DEBUGADD(4, (" NTLMSSP_NEGOTIATE_NETWARE\n"));
if (neg_flags & NTLMSSP_NEGOTIATE_NTLM)
DEBUGADD(4, (" NTLMSSP_NEGOTIATE_NTLM\n"));
if (neg_flags & NTLMSSP_NEGOTIATE_DOMAIN_SUPPLIED)
DEBUGADD(4, (" NTLMSSP_NEGOTIATE_DOMAIN_SUPPLIED\n"));
if (neg_flags & NTLMSSP_NEGOTIATE_WORKSTATION_SUPPLIED)
DEBUGADD(4, (" NTLMSSP_NEGOTIATE_WORKSTATION_SUPPLIED\n"));
if (neg_flags & NTLMSSP_NEGOTIATE_THIS_IS_LOCAL_CALL)
DEBUGADD(4, (" NTLMSSP_NEGOTIATE_THIS_IS_LOCAL_CALL\n"));
if (neg_flags & NTLMSSP_NEGOTIATE_ALWAYS_SIGN)
DEBUGADD(4, (" NTLMSSP_NEGOTIATE_ALWAYS_SIGN\n"));
if (neg_flags & NTLMSSP_NEGOTIATE_NTLM2)
DEBUGADD(4, (" NTLMSSP_NEGOTIATE_NTLM2\n"));
if (neg_flags & NTLMSSP_CHAL_TARGET_INFO)
DEBUGADD(4, (" NTLMSSP_CHAL_TARGET_INFO\n"));
if (neg_flags & NTLMSSP_NEGOTIATE_128)
DEBUGADD(4, (" NTLMSSP_NEGOTIATE_128\n"));
if (neg_flags & NTLMSSP_NEGOTIATE_KEY_EXCH)
DEBUGADD(4, (" NTLMSSP_NEGOTIATE_KEY_EXCH\n"));
}
static NTSTATUS gensec_ntlmssp_magic(struct gensec_security *gensec_security,
const DATA_BLOB *first_packet)
{
if (first_packet->length > 8 && memcmp("NTLMSSP\0", first_packet->data, 8) == 0) {
return NT_STATUS_OK;
} else {
return NT_STATUS_INVALID_PARAMETER;
}
}
/**
* Next state function for the wrapped NTLMSSP state machine
*
* @param gensec_security GENSEC state, initialised to NTLMSSP
* @param out_mem_ctx The TALLOC_CTX for *out to be allocated on
* @param in The request, as a DATA_BLOB
* @param out The reply, as an talloc()ed DATA_BLOB, on *out_mem_ctx
* @return Error, MORE_PROCESSING_REQUIRED if a reply is sent,
* or NT_STATUS_OK if the user is authenticated.
*/
static NTSTATUS gensec_ntlmssp_update(struct gensec_security *gensec_security,
TALLOC_CTX *out_mem_ctx,
const DATA_BLOB input, DATA_BLOB *out)
{
struct gensec_ntlmssp_state *gensec_ntlmssp_state = gensec_security->private_data;
NTSTATUS status;
uint32_t ntlmssp_command;
int i;
*out = data_blob(NULL, 0);
if (gensec_ntlmssp_state->expected_state == NTLMSSP_DONE) {
/* We are strict here because other modules, which we
* don't fully control (such as GSSAPI) are also
* strict, but are tested less often */
DEBUG(1, ("Called NTLMSSP after state machine was 'done'\n"));
return NT_STATUS_INVALID_PARAMETER;
}
if (!out_mem_ctx) {
/* if the caller doesn't want to manage/own the memory,
we can put it on our context */
out_mem_ctx = gensec_ntlmssp_state;
}
if (!input.length) {
switch (gensec_ntlmssp_state->role) {
case NTLMSSP_CLIENT:
ntlmssp_command = NTLMSSP_INITIAL;
break;
case NTLMSSP_SERVER:
if (gensec_security->want_features & GENSEC_FEATURE_DATAGRAM_MODE) {
/* 'datagram' mode - no neg packet */
ntlmssp_command = NTLMSSP_NEGOTIATE;
} else {
/* This is normal in SPNEGO mech negotiation fallback */
DEBUG(2, ("Failed to parse NTLMSSP packet: zero length\n"));
return NT_STATUS_INVALID_PARAMETER;
}
break;
}
} else {
if (!msrpc_parse(gensec_ntlmssp_state,
&input, "Cd",
"NTLMSSP",
&ntlmssp_command)) {
DEBUG(1, ("Failed to parse NTLMSSP packet, could not extract NTLMSSP command\n"));
dump_data(2, input.data, input.length);
return NT_STATUS_INVALID_PARAMETER;
}
}
if (ntlmssp_command != gensec_ntlmssp_state->expected_state) {
DEBUG(2, ("got NTLMSSP command %u, expected %u\n", ntlmssp_command, gensec_ntlmssp_state->expected_state));
return NT_STATUS_INVALID_PARAMETER;
}
for (i=0; i < ARRAY_SIZE(ntlmssp_callbacks); i++) {
if (ntlmssp_callbacks[i].role == gensec_ntlmssp_state->role
&& ntlmssp_callbacks[i].ntlmssp_command == ntlmssp_command) {
status = ntlmssp_callbacks[i].fn(gensec_security, out_mem_ctx, input, out);
break;
}
}
if (i == ARRAY_SIZE(ntlmssp_callbacks)) {
DEBUG(1, ("failed to find NTLMSSP callback for NTLMSSP mode %u, command %u\n",
gensec_ntlmssp_state->role, ntlmssp_command));
return NT_STATUS_INVALID_PARAMETER;
}
if (!NT_STATUS_IS_OK(status)) {
/* error or more processing required */
return status;
}
return status;
}
/**
* Return the NTLMSSP master session key
*
* @param gensec_ntlmssp_state NTLMSSP State
*/
NTSTATUS gensec_ntlmssp_session_key(struct gensec_security *gensec_security,
DATA_BLOB *session_key)
{
struct gensec_ntlmssp_state *gensec_ntlmssp_state = gensec_security->private_data;
if (!gensec_ntlmssp_state->session_key.data) {
return NT_STATUS_NO_USER_SESSION_KEY;
}
*session_key = gensec_ntlmssp_state->session_key;
return NT_STATUS_OK;
}
void ntlmssp_handle_neg_flags(struct gensec_ntlmssp_state *gensec_ntlmssp_state,
uint32_t neg_flags, BOOL allow_lm)
{
if (neg_flags & NTLMSSP_NEGOTIATE_UNICODE) {
gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_UNICODE;
gensec_ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_OEM;
gensec_ntlmssp_state->unicode = True;
} else {
gensec_ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_UNICODE;
gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_OEM;
gensec_ntlmssp_state->unicode = False;
}
if ((neg_flags & NTLMSSP_NEGOTIATE_LM_KEY) && allow_lm && !gensec_ntlmssp_state->use_ntlmv2) {
/* other end forcing us to use LM */
gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_LM_KEY;
gensec_ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_NTLM2;
} else {
gensec_ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_LM_KEY;
}
if (neg_flags & NTLMSSP_NEGOTIATE_ALWAYS_SIGN) {
gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_ALWAYS_SIGN;
}
if (!(neg_flags & NTLMSSP_NEGOTIATE_SIGN)) {
gensec_ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_SIGN;
}
if (!(neg_flags & NTLMSSP_NEGOTIATE_SEAL)) {
gensec_ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_SEAL;
}
if (!(neg_flags & NTLMSSP_NEGOTIATE_NTLM2)) {
gensec_ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_NTLM2;
}
if (!(neg_flags & NTLMSSP_NEGOTIATE_128)) {
gensec_ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_128;
if (neg_flags & NTLMSSP_NEGOTIATE_56) {
gensec_ntlmssp_state->neg_flags |= NTLMSSP_NEGOTIATE_56;
}
}
if (!(neg_flags & NTLMSSP_NEGOTIATE_56)) {
gensec_ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_56;
}
if (!(neg_flags & NTLMSSP_NEGOTIATE_KEY_EXCH)) {
gensec_ntlmssp_state->neg_flags &= ~NTLMSSP_NEGOTIATE_KEY_EXCH;
}
if ((neg_flags & NTLMSSP_REQUEST_TARGET)) {
gensec_ntlmssp_state->neg_flags |= NTLMSSP_REQUEST_TARGET;
}
}
/**
Weaken NTLMSSP keys to cope with down-level clients and servers.
We probably should have some parameters to control this, but as
it only occours for LM_KEY connections, and this is controlled
by the client lanman auth/lanman auth parameters, it isn't too bad.
*/
void ntlmssp_weaken_keys(struct gensec_ntlmssp_state *gensec_ntlmssp_state)
{
/* Key weakening not performed on the master key for NTLM2
and does not occour for NTLM1. Therefore we only need
to do this for the LM_KEY.
*/
if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_LM_KEY) {
if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_128) {
} else if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_56) {
gensec_ntlmssp_state->session_key.data[7] = 0xa0;
} else { /* forty bits */
gensec_ntlmssp_state->session_key.data[5] = 0xe5;
gensec_ntlmssp_state->session_key.data[6] = 0x38;
gensec_ntlmssp_state->session_key.data[7] = 0xb0;
}
gensec_ntlmssp_state->session_key.length = 8;
}
}
static BOOL gensec_ntlmssp_have_feature(struct gensec_security *gensec_security,
uint32_t feature)
{
struct gensec_ntlmssp_state *gensec_ntlmssp_state = gensec_security->private_data;
if (feature & GENSEC_FEATURE_SIGN) {
if (!gensec_ntlmssp_state->session_key.length) {
return False;
}
if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_SIGN) {
return True;
}
}
if (feature & GENSEC_FEATURE_SEAL) {
if (!gensec_ntlmssp_state->session_key.length) {
return False;
}
if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_SEAL) {
return True;
}
}
if (feature & GENSEC_FEATURE_SESSION_KEY) {
if (gensec_ntlmssp_state->session_key.length) {
return True;
}
}
if (feature & GENSEC_FEATURE_DCE_STYLE) {
return True;
}
if (feature & GENSEC_FEATURE_ASYNC_REPLIES) {
if (gensec_ntlmssp_state->neg_flags & NTLMSSP_NEGOTIATE_NTLM2) {
return True;
}
}
return False;
}
NTSTATUS gensec_ntlmssp_start(struct gensec_security *gensec_security)
{
struct gensec_ntlmssp_state *gensec_ntlmssp_state;
gensec_ntlmssp_state = talloc_zero(gensec_security, struct gensec_ntlmssp_state);
if (!gensec_ntlmssp_state) {
return NT_STATUS_NO_MEMORY;
}
gensec_ntlmssp_state->auth_context = NULL;
gensec_ntlmssp_state->server_info = NULL;
gensec_security->private_data = gensec_ntlmssp_state;
return NT_STATUS_OK;
}
static const char *gensec_ntlmssp_oids[] = {
GENSEC_OID_NTLMSSP,
NULL
};
static const struct gensec_security_ops gensec_ntlmssp_security_ops = {
.name = "ntlmssp",
.sasl_name = "NTLM",
.auth_type = DCERPC_AUTH_TYPE_NTLMSSP,
.oid = gensec_ntlmssp_oids,
.client_start = gensec_ntlmssp_client_start,
.server_start = gensec_ntlmssp_server_start,
.magic = gensec_ntlmssp_magic,
.update = gensec_ntlmssp_update,
.sig_size = gensec_ntlmssp_sig_size,
.sign_packet = gensec_ntlmssp_sign_packet,
.check_packet = gensec_ntlmssp_check_packet,
.seal_packet = gensec_ntlmssp_seal_packet,
.unseal_packet = gensec_ntlmssp_unseal_packet,
.wrap = gensec_ntlmssp_wrap,
.unwrap = gensec_ntlmssp_unwrap,
.session_key = gensec_ntlmssp_session_key,
.session_info = gensec_ntlmssp_session_info,
.have_feature = gensec_ntlmssp_have_feature,
.enabled = True
};
NTSTATUS gensec_ntlmssp_init(void)
{
NTSTATUS ret;
ret = gensec_register(&gensec_ntlmssp_security_ops);
if (!NT_STATUS_IS_OK(ret)) {
DEBUG(0,("Failed to register '%s' gensec backend!\n",
gensec_ntlmssp_security_ops.name));
return ret;
}
return ret;
}