r10981: Pull code to decide between and implement NTLMv2, NTLM and LM

authentication out of the various callers and into the kitchen
sink.. err, credentials subsystem.

This should ensure consistant logic, as well as get us one step closer
to security=server operation in future.

Andrew Bartlett
(This used to be commit 09c95763301c0f7770d56462e8af4169b8c171fb)

3 files changed, 193 insertions, 14 deletions

diff --git a/source4/auth/credentials/config.mk b/source4/auth/credentials/config.mk
index 65505d87bf..74f3f07bef 100644
--- a/source4/auth/credentials/config.mk
+++ b/source4/auth/credentials/config.mk
@@ -3,7 +3,8 @@
 [SUBSYSTEM::CREDENTIALS]
 INIT_OBJ_FILES = auth/credentials/credentials.o
 ADD_OBJ_FILES = auth/credentials/credentials_files.o \
-		auth/credentials/credentials_krb5.o
+		auth/credentials/credentials_krb5.o \
+		auth/credentials/credentials_ntlm.o
 REQUIRED_SUBSYSTEMS = \
 		HEIMDAL
 # End SUBSYSTEM GENSEC
diff --git a/source4/auth/credentials/credentials.c b/source4/auth/credentials/credentials.c
index 11b413b1c6..38c9ba30e8 100644
--- a/source4/auth/credentials/credentials.c
+++ b/source4/auth/credentials/credentials.c
@@ -293,19 +293,6 @@ BOOL cli_credentials_set_domain_callback(struct cli_credentials *cred,
 	return False;
 }
 
-void cli_credentials_get_ntlm_username_domain(struct cli_credentials *cred, TALLOC_CTX *mem_ctx, 
-					      const char **username, 
-					      const char **domain) 
-{
-	if (cred->principal_obtained > cred->username_obtained) {
-		*domain = talloc_strdup(mem_ctx, "");
-		*username = cli_credentials_get_principal(cred, mem_ctx);
-	} else {
-		*domain = cli_credentials_get_domain(cred);
-		*username = cli_credentials_get_username(cred);
-	}
-}
-
 /**
  * Obtain the Kerberos realm for this credentials context.
  * @param cred credentials context
diff --git a/source4/auth/credentials/credentials_ntlm.c b/source4/auth/credentials/credentials_ntlm.c
new file mode 100644
index 0000000000..0dfd106a3c
--- /dev/null
+++ b/source4/auth/credentials/credentials_ntlm.c
@@ -0,0 +1,191 @@
+/* 
+   Unix SMB/CIFS implementation.
+
+   User credentials handling
+
+   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 "lib/ldb/include/ldb.h"
+#include "librpc/gen_ndr/ndr_samr.h" /* for struct samrPassword */
+#include "lib/crypto/crypto.h"
+
+void cli_credentials_get_ntlm_username_domain(struct cli_credentials *cred, TALLOC_CTX *mem_ctx, 
+					      const char **username, 
+					      const char **domain) 
+{
+	if (cred->principal_obtained > cred->username_obtained) {
+		*domain = talloc_strdup(mem_ctx, "");
+		*username = cli_credentials_get_principal(cred, mem_ctx);
+	} else {
+		*domain = cli_credentials_get_domain(cred);
+		*username = cli_credentials_get_username(cred);
+	}
+}
+
+NTSTATUS cli_credentials_get_ntlm_response(struct cli_credentials *cred, TALLOC_CTX *mem_ctx, 
+					   int *flags,
+					   DATA_BLOB challenge, DATA_BLOB target_info, 
+					   DATA_BLOB *_lm_response, DATA_BLOB *_nt_response, 
+					   DATA_BLOB *_lm_session_key, DATA_BLOB *_session_key) 
+{
+	const char *user, *domain;
+	DATA_BLOB lm_response, nt_response;
+	DATA_BLOB lm_session_key, session_key;
+	const struct samr_Password *nt_hash;
+	lm_session_key = data_blob(NULL, 0);
+
+	nt_hash = cli_credentials_get_nt_hash(cred, mem_ctx);
+
+	cli_credentials_get_ntlm_username_domain(cred, mem_ctx, &user, &domain);
+
+	if (!nt_hash) {
+		static const uint8_t zeros[16];
+		/* do nothing - blobs are zero length */
+
+		/* session key is all zeros */
+		session_key = data_blob_talloc(mem_ctx, zeros, 16);
+		lm_session_key = data_blob_talloc(mem_ctx, zeros, 16);
+
+		lm_response = data_blob(NULL, 0);
+		nt_response = data_blob(NULL, 0);
+		
+		/* not doing NLTM2 without a password */
+		*flags &= ~CLI_CRED_NTLM2;
+	} else if (*flags & CLI_CRED_NTLMv2_AUTH) {
+
+		if (!target_info.length) {
+			/* be lazy, match win2k - we can't do NTLMv2 without it */
+			DEBUG(1, ("Server did not provide 'target information', required for NTLMv2\n"));
+			return NT_STATUS_INVALID_PARAMETER;
+		}
+
+		/* TODO: if the remote server is standalone, then we should replace 'domain'
+		   with the server name as supplied above */
+		
+		if (!SMBNTLMv2encrypt_hash(mem_ctx,
+					   user, 
+					   domain, 
+					   nt_hash->hash, &challenge, 
+					   &target_info, 
+					   &lm_response, &nt_response, 
+					   NULL, &session_key)) {
+			return NT_STATUS_NO_MEMORY;
+		}
+
+		/* LM Key is incompatible... */
+		*flags &= ~CLI_CRED_LANMAN_AUTH;
+	} else if (*flags & CLI_CRED_NTLM2) {
+		struct MD5Context md5_session_nonce_ctx;
+		uint8_t session_nonce[16];
+		uint8_t session_nonce_hash[16];
+		uint8_t user_session_key[16];
+		
+		lm_response = data_blob_talloc(mem_ctx, NULL, 24);
+		generate_random_buffer(lm_response.data, 8);
+		memset(lm_response.data+8, 0, 16);
+
+		memcpy(session_nonce, challenge.data, 8);
+		memcpy(&session_nonce[8], lm_response.data, 8);
+	
+		MD5Init(&md5_session_nonce_ctx);
+		MD5Update(&md5_session_nonce_ctx, challenge.data, 8);
+		MD5Update(&md5_session_nonce_ctx, lm_response.data, 8);
+		MD5Final(session_nonce_hash, &md5_session_nonce_ctx);
+
+		DEBUG(5, ("NTLMSSP challenge set by NTLM2\n"));
+		DEBUG(5, ("challenge is: \n"));
+		dump_data(5, session_nonce_hash, 8);
+		
+		nt_response = data_blob_talloc(mem_ctx, NULL, 24);
+		SMBOWFencrypt(nt_hash->hash,
+			      session_nonce_hash,
+			      nt_response.data);
+		
+		session_key = data_blob_talloc(mem_ctx, NULL, 16);
+
+		SMBsesskeygen_ntv1(nt_hash->hash, user_session_key);
+		hmac_md5(user_session_key, session_nonce, sizeof(session_nonce), session_key.data);
+		dump_data_pw("NTLM2 session key:\n", session_key.data, session_key.length);
+
+		/* LM Key is incompatible... */
+		*flags &= ~CLI_CRED_LANMAN_AUTH;
+	} else {
+		nt_response = data_blob_talloc(mem_ctx, NULL, 24);
+		SMBOWFencrypt(nt_hash->hash, challenge.data,
+			      nt_response.data);
+		
+		session_key = data_blob_talloc(mem_ctx, NULL, 16);
+		SMBsesskeygen_ntv1(nt_hash->hash, session_key.data);
+		dump_data_pw("NT session key:\n", session_key.data, session_key.length);
+
+		/* lanman auth is insecure, it may be disabled.  
+		   We may also not have a password */
+		if (*flags & CLI_CRED_LANMAN_AUTH) {
+			const char *password;
+			password = cli_credentials_get_password(cred);
+			if (!password) {
+				lm_response = nt_response;
+			} else {
+				uint8_t lm_hash[16];
+				lm_response = data_blob_talloc(mem_ctx, NULL, 24);
+				if (!SMBencrypt(password,challenge.data,
+						lm_response.data)) {
+					/* If the LM password was too long (and therefore the LM hash being
+					   of the first 14 chars only), don't send it.
+
+					   We don't have any better options but to send the NT response 
+					*/
+					data_blob_free(&lm_response);
+					lm_response = nt_response;
+					/* LM Key is incompatible with 'long' passwords */
+					*flags &= ~CLI_CRED_LANMAN_AUTH;
+				} else {
+					E_deshash(password, lm_hash);
+					lm_session_key = data_blob_talloc(mem_ctx, NULL, 16);
+					memcpy(lm_session_key.data, lm_hash, 8);
+					memset(&lm_session_key.data[8], '\0', 8);
+					
+					if (!(*flags & CLI_CRED_NTLM_AUTH)) {
+						session_key = lm_session_key;
+					}
+				}
+			}
+		} else {
+			/* LM Key is incompatible... */
+			lm_response = nt_response;
+			*flags &= ~CLI_CRED_LANMAN_AUTH;
+		}
+	}
+	if (_lm_response) {
+		*_lm_response = lm_response;
+	}
+	if (_nt_response) {
+		*_nt_response = nt_response;
+	}
+	if (_lm_session_key) {
+		*_lm_session_key = lm_session_key;
+	}
+	if (_session_key) {
+		*_session_key = session_key;
+	}
+	return NT_STATUS_OK;
+}
+