1
0
mirror of https://github.com/samba-team/samba.git synced 2024-12-24 21:34:56 +03:00
samba-mirror/source4/smb_server/smb/negprot.c
Andrew Bartlett 107f7b9efa r13911: Make these debug messages clearer.
(This used to be commit 9c8350c64b)
2007-10-10 13:52:23 -05:00

527 lines
17 KiB
C

/*
Unix SMB/CIFS implementation.
negprot reply code
Copyright (C) Andrew Tridgell 1992-1998
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 "smb_server/smb_server.h"
#include "libcli/smb2/smb2.h"
#include "smb_server/smb2/smb2_server.h"
#include "smbd/service_stream.h"
#include "lib/stream/packet.h"
/* initialise the auth_context for this server and return the cryptkey */
static NTSTATUS get_challenge(struct smbsrv_connection *smb_conn, uint8_t buff[8])
{
NTSTATUS nt_status;
const uint8_t *challenge;
/* muliple negprots are not premitted */
if (smb_conn->negotiate.auth_context) {
DEBUG(3,("get challenge: is this a secondary negprot? auth_context is non-NULL!\n"));
return NT_STATUS_FOOBAR;
}
DEBUG(10, ("get challenge: creating negprot_global_auth_context\n"));
nt_status = auth_context_create(smb_conn, lp_auth_methods(),
&smb_conn->negotiate.auth_context,
smb_conn->connection->event.ctx);
if (!NT_STATUS_IS_OK(nt_status)) {
DEBUG(0, ("auth_context_create() returned %s", nt_errstr(nt_status)));
return nt_status;
}
nt_status = auth_get_challenge(smb_conn->negotiate.auth_context, &challenge);
if (!NT_STATUS_IS_OK(nt_status)) {
DEBUG(0, ("auth_get_challenge() returned %s", nt_errstr(nt_status)));
return nt_status;
}
memcpy(buff, challenge, 8);
return NT_STATUS_OK;
}
/****************************************************************************
Reply for the core protocol.
****************************************************************************/
static void reply_corep(struct smbsrv_request *req, uint16_t choice)
{
smbsrv_setup_reply(req, 1, 0);
SSVAL(req->out.vwv, VWV(0), choice);
req->smb_conn->negotiate.protocol = PROTOCOL_CORE;
if (req->smb_conn->signing.mandatory_signing) {
smbsrv_terminate_connection(req->smb_conn,
"CORE does not support SMB signing, and it is mandatory\n");
return;
}
smbsrv_send_reply(req);
}
/****************************************************************************
Reply for the coreplus protocol.
this is quite incomplete - we only fill in a small part of the reply, but as nobody uses
this any more it probably doesn't matter
****************************************************************************/
static void reply_coreplus(struct smbsrv_request *req, uint16_t choice)
{
uint16_t raw = (lp_readraw()?1:0) | (lp_writeraw()?2:0);
smbsrv_setup_reply(req, 13, 0);
/* Reply, SMBlockread, SMBwritelock supported. */
SCVAL(req->out.hdr,HDR_FLG,
CVAL(req->out.hdr, HDR_FLG) | FLAG_SUPPORT_LOCKREAD);
SSVAL(req->out.vwv, VWV(0), choice);
SSVAL(req->out.vwv, VWV(1), 0x1); /* user level security, don't encrypt */
/* tell redirector we support
readbraw and writebraw (possibly) */
SSVAL(req->out.vwv, VWV(5), raw);
req->smb_conn->negotiate.protocol = PROTOCOL_COREPLUS;
if (req->smb_conn->signing.mandatory_signing) {
smbsrv_terminate_connection(req->smb_conn,
"COREPLUS does not support SMB signing, and it is mandatory\n");
return;
}
smbsrv_send_reply(req);
}
/****************************************************************************
Reply for the lanman 1.0 protocol.
****************************************************************************/
static void reply_lanman1(struct smbsrv_request *req, uint16_t choice)
{
int raw = (lp_readraw()?1:0) | (lp_writeraw()?2:0);
int secword=0;
time_t t = req->request_time.tv_sec;
req->smb_conn->negotiate.encrypted_passwords = lp_encrypted_passwords();
if (lp_security() != SEC_SHARE)
secword |= NEGOTIATE_SECURITY_USER_LEVEL;
if (req->smb_conn->negotiate.encrypted_passwords)
secword |= NEGOTIATE_SECURITY_CHALLENGE_RESPONSE;
req->smb_conn->negotiate.protocol = PROTOCOL_LANMAN1;
smbsrv_setup_reply(req, 13, req->smb_conn->negotiate.encrypted_passwords ? 8 : 0);
/* SMBlockread, SMBwritelock supported. */
SCVAL(req->out.hdr,HDR_FLG,
CVAL(req->out.hdr, HDR_FLG) | FLAG_SUPPORT_LOCKREAD);
SSVAL(req->out.vwv, VWV(0), choice);
SSVAL(req->out.vwv, VWV(1), secword);
SSVAL(req->out.vwv, VWV(2), req->smb_conn->negotiate.max_recv);
SSVAL(req->out.vwv, VWV(3), lp_maxmux());
SSVAL(req->out.vwv, VWV(4), 1);
SSVAL(req->out.vwv, VWV(5), raw);
SIVAL(req->out.vwv, VWV(6), req->smb_conn->connection->server_id);
srv_push_dos_date(req->smb_conn, req->out.vwv, VWV(8), t);
SSVAL(req->out.vwv, VWV(10), req->smb_conn->negotiate.zone_offset/60);
SIVAL(req->out.vwv, VWV(11), 0); /* reserved */
/* Create a token value and add it to the outgoing packet. */
if (req->smb_conn->negotiate.encrypted_passwords) {
NTSTATUS nt_status;
SSVAL(req->out.vwv, VWV(11), 8);
nt_status = get_challenge(req->smb_conn, req->out.data);
if (!NT_STATUS_IS_OK(nt_status)) {
smbsrv_terminate_connection(req->smb_conn, "LANMAN1 get_challenge failed\n");
return;
}
}
if (req->smb_conn->signing.mandatory_signing) {
smbsrv_terminate_connection(req->smb_conn,
"LANMAN1 does not support SMB signing, and it is mandatory\n");
return;
}
smbsrv_send_reply(req);
}
/****************************************************************************
Reply for the lanman 2.0 protocol.
****************************************************************************/
static void reply_lanman2(struct smbsrv_request *req, uint16_t choice)
{
int raw = (lp_readraw()?1:0) | (lp_writeraw()?2:0);
int secword=0;
time_t t = req->request_time.tv_sec;
req->smb_conn->negotiate.encrypted_passwords = lp_encrypted_passwords();
if (lp_security() != SEC_SHARE)
secword |= NEGOTIATE_SECURITY_USER_LEVEL;
if (req->smb_conn->negotiate.encrypted_passwords)
secword |= NEGOTIATE_SECURITY_CHALLENGE_RESPONSE;
req->smb_conn->negotiate.protocol = PROTOCOL_LANMAN2;
smbsrv_setup_reply(req, 13, 0);
SSVAL(req->out.vwv, VWV(0), choice);
SSVAL(req->out.vwv, VWV(1), secword);
SSVAL(req->out.vwv, VWV(2), req->smb_conn->negotiate.max_recv);
SSVAL(req->out.vwv, VWV(3), lp_maxmux());
SSVAL(req->out.vwv, VWV(4), 1);
SSVAL(req->out.vwv, VWV(5), raw);
SIVAL(req->out.vwv, VWV(6), req->smb_conn->connection->server_id);
srv_push_dos_date(req->smb_conn, req->out.vwv, VWV(8), t);
SSVAL(req->out.vwv, VWV(10), req->smb_conn->negotiate.zone_offset/60);
SIVAL(req->out.vwv, VWV(11), 0);
/* Create a token value and add it to the outgoing packet. */
if (req->smb_conn->negotiate.encrypted_passwords) {
SSVAL(req->out.vwv, VWV(11), 8);
req_grow_data(req, 8);
get_challenge(req->smb_conn, req->out.data);
}
req_push_str(req, NULL, lp_workgroup(), -1, STR_TERMINATE);
if (req->smb_conn->signing.mandatory_signing) {
smbsrv_terminate_connection(req->smb_conn,
"LANMAN2 does not support SMB signing, and it is mandatory\n");
return;
}
smbsrv_send_reply(req);
}
static void reply_nt1_orig(struct smbsrv_request *req)
{
/* Create a token value and add it to the outgoing packet. */
if (req->smb_conn->negotiate.encrypted_passwords) {
req_grow_data(req, 8);
/* note that we do not send a challenge at all if
we are using plaintext */
get_challenge(req->smb_conn, req->out.ptr);
req->out.ptr += 8;
SCVAL(req->out.vwv+1, VWV(16), 8);
}
req_push_str(req, NULL, lp_workgroup(), -1, STR_UNICODE|STR_TERMINATE|STR_NOALIGN);
req_push_str(req, NULL, lp_netbios_name(), -1, STR_UNICODE|STR_TERMINATE|STR_NOALIGN);
DEBUG(3,("not using extended security (SPNEGO or NTLMSSP)\n"));
}
/****************************************************************************
Reply for the nt protocol.
****************************************************************************/
static void reply_nt1(struct smbsrv_request *req, uint16_t choice)
{
/* dual names + lock_and_read + nt SMBs + remote API calls */
int capabilities;
int secword=0;
time_t t = req->request_time.tv_sec;
NTTIME nttime;
BOOL negotiate_spnego = False;
unix_to_nt_time(&nttime, t);
capabilities =
CAP_NT_FIND | CAP_LOCK_AND_READ |
CAP_LEVEL_II_OPLOCKS | CAP_NT_SMBS | CAP_RPC_REMOTE_APIS;
req->smb_conn->negotiate.encrypted_passwords = lp_encrypted_passwords();
/* do spnego in user level security if the client
supports it and we can do encrypted passwords */
if (req->smb_conn->negotiate.encrypted_passwords &&
(lp_security() != SEC_SHARE) &&
lp_use_spnego() &&
(req->flags2 & FLAGS2_EXTENDED_SECURITY)) {
negotiate_spnego = True;
capabilities |= CAP_EXTENDED_SECURITY;
}
if (lp_unix_extensions()) {
capabilities |= CAP_UNIX;
}
if (lp_large_readwrite()) {
capabilities |= CAP_LARGE_READX | CAP_LARGE_WRITEX | CAP_W2K_SMBS;
}
capabilities |= CAP_LARGE_FILES;
if (lp_readraw() && lp_writeraw()) {
capabilities |= CAP_RAW_MODE;
}
/* allow for disabling unicode */
if (lp_unicode()) {
capabilities |= CAP_UNICODE;
}
if (lp_nt_status_support()) {
capabilities |= CAP_STATUS32;
}
if (lp_host_msdfs()) {
capabilities |= CAP_DFS;
}
if (lp_security() != SEC_SHARE) {
secword |= NEGOTIATE_SECURITY_USER_LEVEL;
}
if (req->smb_conn->negotiate.encrypted_passwords) {
secword |= NEGOTIATE_SECURITY_CHALLENGE_RESPONSE;
}
if (req->smb_conn->signing.allow_smb_signing) {
secword |= NEGOTIATE_SECURITY_SIGNATURES_ENABLED;
}
if (req->smb_conn->signing.mandatory_signing) {
secword |= NEGOTIATE_SECURITY_SIGNATURES_REQUIRED;
}
req->smb_conn->negotiate.protocol = PROTOCOL_NT1;
smbsrv_setup_reply(req, 17, 0);
SSVAL(req->out.vwv, VWV(0), choice);
SCVAL(req->out.vwv, VWV(1), secword);
/* notice the strange +1 on vwv here? That's because
this is the one and only SMB packet that is malformed in
the specification - all the command words after the secword
are offset by 1 byte */
SSVAL(req->out.vwv+1, VWV(1), lp_maxmux());
SSVAL(req->out.vwv+1, VWV(2), 1); /* num vcs */
SIVAL(req->out.vwv+1, VWV(3), req->smb_conn->negotiate.max_recv);
SIVAL(req->out.vwv+1, VWV(5), 0x10000); /* raw size. full 64k */
SIVAL(req->out.vwv+1, VWV(7), req->smb_conn->connection->server_id); /* session key */
SIVAL(req->out.vwv+1, VWV(9), capabilities);
push_nttime(req->out.vwv+1, VWV(11), nttime);
SSVALS(req->out.vwv+1,VWV(15), req->smb_conn->negotiate.zone_offset/60);
if (!negotiate_spnego) {
reply_nt1_orig(req);
} else {
struct cli_credentials *server_credentials;
struct gensec_security *gensec_security;
DATA_BLOB null_data_blob = data_blob(NULL, 0);
DATA_BLOB blob;
const char *oid;
NTSTATUS nt_status = gensec_server_start(req->smb_conn,
&gensec_security,
req->smb_conn->connection->event.ctx);
if (!NT_STATUS_IS_OK(nt_status)) {
DEBUG(0, ("Failed to start GENSEC: %s\n", nt_errstr(nt_status)));
smbsrv_terminate_connection(req->smb_conn, "Failed to start GENSEC\n");
return;
}
if (req->smb_conn->negotiate.auth_context) {
smbsrv_terminate_connection(req->smb_conn, "reply_nt1: is this a secondary negprot? auth_context is non-NULL!\n");
return;
}
server_credentials
= cli_credentials_init(req);
if (!server_credentials) {
smbsrv_terminate_connection(req->smb_conn, "Failed to init server credentials\n");
return;
}
cli_credentials_set_conf(server_credentials);
nt_status = cli_credentials_set_machine_account(server_credentials);
if (!NT_STATUS_IS_OK(nt_status)) {
DEBUG(10, ("Failed to obtain server credentials, perhaps a standalone server?: %s\n", nt_errstr(nt_status)));
talloc_free(server_credentials);
server_credentials = NULL;
}
req->smb_conn->negotiate.server_credentials = talloc_steal(req->smb_conn, server_credentials);
gensec_set_target_service(gensec_security, "cifs");
gensec_set_credentials(gensec_security, server_credentials);
oid = GENSEC_OID_SPNEGO;
nt_status = gensec_start_mech_by_oid(gensec_security, oid);
if (NT_STATUS_IS_OK(nt_status)) {
/* Get and push the proposed OID list into the packets */
nt_status = gensec_update(gensec_security, req, null_data_blob, &blob);
if (!NT_STATUS_IS_OK(nt_status) && !NT_STATUS_EQUAL(nt_status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
DEBUG(1, ("Failed to get SPNEGO to give us the first token: %s\n", nt_errstr(nt_status)));
}
}
if (NT_STATUS_EQUAL(nt_status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
DEBUG(3,("using SPNEGO\n"));
} else {
DEBUG(5, ("Failed to start SPNEGO, falling back to NTLMSSP only: %s\n", nt_errstr(nt_status)));
oid = GENSEC_OID_NTLMSSP;
nt_status = gensec_start_mech_by_oid(gensec_security, oid);
if (!NT_STATUS_IS_OK(nt_status)) {
DEBUG(0, ("Failed to start SPNEGO as well as NTLMSSP fallback: %s\n", nt_errstr(nt_status)));
reply_nt1_orig(req);
return;
}
/* NTLMSSP is a client-first exchange */
blob = data_blob(NULL, 0);
DEBUG(3,("using raw-NTLMSSP\n"));
}
req->smb_conn->negotiate.oid = oid;
req_grow_data(req, blob.length + 16);
/* a NOT very random guid, perhaps we should get it
* from the credentials (kitchen sink...) */
memset(req->out.ptr, '\0', 16);
req->out.ptr += 16;
memcpy(req->out.ptr, blob.data, blob.length);
SCVAL(req->out.vwv+1, VWV(16), blob.length + 16);
req->out.ptr += blob.length;
}
smbsrv_send_reply_nosign(req);
}
/*
after a SMB2 2.001 negprot reply to a SMB negprot request
no (SMB or SMB2) requests are allowed anymore,
vista resets the connection in this case
*/
static NTSTATUS smbsrv_recv_disabled_request(void *private, DATA_BLOB blob)
{
struct smbsrv_connection *smb_conn = talloc_get_type(private, struct smbsrv_connection);
smbsrv_terminate_connection(smb_conn, "Receive Packet after SMB -> SMB2 negprot");
return NT_STATUS_OK;
}
/****************************************************************************
Reply for the SMB2 2.001 protocol
****************************************************************************/
static void reply_smb2(struct smbsrv_request *req, uint16_t choice)
{
struct smbsrv_connection *smb_conn = req->smb_conn;
/* reply with a SMB2 packet */
smb2srv_reply_smb_negprot(req);
req = NULL;
/* disallow requests */
packet_set_callback(smb_conn->packet, smbsrv_recv_disabled_request);
}
/* List of supported protocols, most desired first */
static const struct {
const char *proto_name;
const char *short_name;
void (*proto_reply_fn)(struct smbsrv_request *req, uint16_t choice);
int protocol_level;
} supported_protocols[] = {
{"SMB 2.001", "SMB2", reply_smb2, PROTOCOL_SMB2},
{"NT LANMAN 1.0", "NT1", reply_nt1, PROTOCOL_NT1},
{"NT LM 0.12", "NT1", reply_nt1, PROTOCOL_NT1},
{"LANMAN2.1", "LANMAN2", reply_lanman2, PROTOCOL_LANMAN2},
{"LM1.2X002", "LANMAN2", reply_lanman2, PROTOCOL_LANMAN2},
{"Samba", "LANMAN2", reply_lanman2, PROTOCOL_LANMAN2},
{"DOS LM1.2X002", "LANMAN2", reply_lanman2, PROTOCOL_LANMAN2},
{"Windows for Workgroups 3.1a", "LANMAN1", reply_lanman1, PROTOCOL_LANMAN1},
{"LANMAN1.0", "LANMAN1", reply_lanman1, PROTOCOL_LANMAN1},
{"MICROSOFT NETWORKS 3.0", "LANMAN1", reply_lanman1, PROTOCOL_LANMAN1},
{"MICROSOFT NETWORKS 1.03", "COREPLUS", reply_coreplus, PROTOCOL_COREPLUS},
{"PC NETWORK PROGRAM 1.0", "CORE", reply_corep, PROTOCOL_CORE},
{NULL,NULL,NULL,0},
};
/****************************************************************************
Reply to a negprot.
****************************************************************************/
void smbsrv_reply_negprot(struct smbsrv_request *req)
{
int protocol;
uint8_t *p;
uint32_t protos_count = 0;
char **protos = NULL;
if (req->smb_conn->negotiate.done_negprot) {
smbsrv_terminate_connection(req->smb_conn, "multiple negprot's are not permitted");
return;
}
req->smb_conn->negotiate.done_negprot = True;
p = req->in.data;
while (True) {
size_t len;
protos = talloc_realloc(req, protos, char *, protos_count + 1);
if (!protos) {
smbsrv_terminate_connection(req->smb_conn, nt_errstr(NT_STATUS_NO_MEMORY));
return;
}
protos[protos_count] = NULL;
len = req_pull_ascii4(req, (const char **)&protos[protos_count], p, STR_ASCII|STR_TERMINATE);
p += len;
if (len == 0 || !protos[protos_count]) break;
DEBUG(3,("Requested protocol [%d][%s]\n", protos_count, protos[protos_count]));
protos_count++;
}
/* Check for protocols, most desirable first */
for (protocol = 0; supported_protocols[protocol].proto_name; protocol++) {
int i;
if (supported_protocols[protocol].protocol_level > lp_maxprotocol()) continue;
if (supported_protocols[protocol].protocol_level < lp_minprotocol()) continue;
for (i = 0; i < protos_count; i++) {
if (strcmp(supported_protocols[protocol].proto_name, protos[i]) != 0) continue;
supported_protocols[protocol].proto_reply_fn(req, i);
sub_set_remote_proto(supported_protocols[protocol].short_name);
DEBUG(3,("Selected protocol [%d][%s]\n",
i, supported_protocols[protocol].proto_name));
return;
}
}
smbsrv_terminate_connection(req->smb_conn, "No protocol supported !");
}