r1461: ntlm_check.c is a server-side peice of code, so it belongs in AUTH.

Andrew Bartlett
(This used to be commit 67ac9600664e93aa2fe9426127313b57ddaec2cf)

2 files changed, 449 insertions, 1 deletions

diff --git a/source4/auth/config.mk b/source4/auth/config.mk
index b4082cb9e5..223f082e6a 100644
--- a/source4/auth/config.mk
+++ b/source4/auth/config.mk
@@ -26,6 +26,7 @@ INIT_OBJ_FILES = \
 ADD_OBJ_FILES = \
 		auth/auth_util.o \
 		auth/pampass.o \
-		auth/pass_check.o
+		auth/pass_check.o \
+		auth/ntlm_check.o
 # End SUBSYSTEM AUTH
 #######################
diff --git a/source4/auth/ntlm_check.c b/source4/auth/ntlm_check.c
new file mode 100644
index 0000000000..f101b230d4
--- /dev/null
+++ b/source4/auth/ntlm_check.c
@@ -0,0 +1,447 @@
+/* 
+   Unix SMB/CIFS implementation.
+   Password and authentication handling
+   Copyright (C) Andrew Bartlett <abartlet@samba.org> 2001-2004
+   Copyright (C) Gerald Carter                             2003
+   Copyright (C) Luke Kenneth Casson Leighton         1996-2000
+   
+   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"
+
+#undef DBGC_CLASS
+#define DBGC_CLASS DBGC_AUTH
+
+/****************************************************************************
+ Core of smb password checking routine.
+****************************************************************************/
+
+static BOOL smb_pwd_check_ntlmv1(const DATA_BLOB *nt_response,
+				 const uint8_t *part_passwd,
+				 const DATA_BLOB *sec_blob,
+				 DATA_BLOB *user_sess_key)
+{
+	/* Finish the encryption of part_passwd. */
+	uint8_t p24[24];
+	
+	if (part_passwd == NULL) {
+		DEBUG(10,("No password set - DISALLOWING access\n"));
+		/* No password set - always false ! */
+		return False;
+	}
+	
+	if (sec_blob->length != 8) {
+		DEBUG(0, ("smb_pwd_check_ntlmv1: incorrect challenge size (%lu)\n", 
+			  (unsigned long)sec_blob->length));
+		return False;
+	}
+	
+	if (nt_response->length != 24) {
+		DEBUG(0, ("smb_pwd_check_ntlmv1: incorrect password length (%lu)\n", 
+			  (unsigned long)nt_response->length));
+		return False;
+	}
+
+	SMBOWFencrypt(part_passwd, sec_blob->data, p24);
+	if (user_sess_key != NULL) {
+		*user_sess_key = data_blob(NULL, 16);
+		SMBsesskeygen_ntv1(part_passwd, user_sess_key->data);
+	}
+	
+	
+#if DEBUG_PASSWORD
+	DEBUG(100,("Part password (P16) was |\n"));
+	dump_data(100, part_passwd, 16);
+	DEBUGADD(100,("Password from client was |\n"));
+	dump_data(100, nt_response->data, nt_response->length);
+	DEBUGADD(100,("Given challenge was |\n"));
+	dump_data(100, sec_blob->data, sec_blob->length);
+	DEBUGADD(100,("Value from encryption was |\n"));
+	dump_data(100, p24, 24);
+#endif
+	return (memcmp(p24, nt_response->data, 24) == 0);
+}
+
+/****************************************************************************
+ Core of smb password checking routine. (NTLMv2, LMv2)
+ Note:  The same code works with both NTLMv2 and LMv2.
+****************************************************************************/
+
+static BOOL smb_pwd_check_ntlmv2(const DATA_BLOB *ntv2_response,
+				 const uint8_t *part_passwd,
+				 const DATA_BLOB *sec_blob,
+				 const char *user, const char *domain,
+				 BOOL upper_case_domain, /* should the domain be transformed into upper case? */
+				 DATA_BLOB *user_sess_key)
+{
+	/* Finish the encryption of part_passwd. */
+	uint8_t kr[16];
+	uint8_t value_from_encryption[16];
+	uint8_t client_response[16];
+	DATA_BLOB client_key_data;
+
+	if (part_passwd == NULL) {
+		DEBUG(10,("No password set - DISALLOWING access\n"));
+		/* No password set - always False */
+		return False;
+	}
+
+	if (sec_blob->length != 8) {
+		DEBUG(0, ("smb_pwd_check_ntlmv2: incorrect challenge size (%lu)\n", 
+			  (unsigned long)sec_blob->length));
+		return False;
+	}
+	
+	if (ntv2_response->length < 24) {
+		/* We MUST have more than 16 bytes, or the stuff below will go
+		   crazy.  No known implementation sends less than the 24 bytes
+		   for LMv2, let alone NTLMv2. */
+		DEBUG(0, ("smb_pwd_check_ntlmv2: incorrect password length (%lu)\n", 
+			  (unsigned long)ntv2_response->length));
+		return False;
+	}
+
+	client_key_data = data_blob(ntv2_response->data+16, ntv2_response->length-16);
+	/* 
+	   todo:  should we be checking this for anything?  We can't for LMv2, 
+	   but for NTLMv2 it is meant to contain the current time etc.
+	*/
+
+	memcpy(client_response, ntv2_response->data, sizeof(client_response));
+
+	if (!ntv2_owf_gen(part_passwd, user, domain, upper_case_domain, kr)) {
+		return False;
+	}
+
+	SMBOWFencrypt_ntv2(kr, sec_blob, &client_key_data, value_from_encryption);
+	if (user_sess_key != NULL) {
+		*user_sess_key = data_blob(NULL, 16);
+		SMBsesskeygen_ntv2(kr, value_from_encryption, user_sess_key->data);
+	}
+
+#if DEBUG_PASSWORD
+	DEBUG(100,("Part password (P16) was |\n"));
+	dump_data(100, part_passwd, 16);
+	DEBUGADD(100,("Password from client was |\n"));
+	dump_data(100, ntv2_response->data, ntv2_response->length);
+	DEBUGADD(100,("Variable data from client was |\n"));
+	dump_data(100, client_key_data.data, client_key_data.length);
+	DEBUGADD(100,("Given challenge was |\n"));
+	dump_data(100, sec_blob->data, sec_blob->length);
+	DEBUGADD(100,("Value from encryption was |\n"));
+	dump_data(100, value_from_encryption, 16);
+#endif
+	data_blob_clear_free(&client_key_data);
+	return (memcmp(value_from_encryption, client_response, 16) == 0);
+}
+
+/**
+ * Check a challenge-response password against the value of the NT or
+ * LM password hash.
+ *
+ * @param mem_ctx talloc context
+ * @param challenge 8-byte challenge.  If all zero, forces plaintext comparison
+ * @param nt_response 'unicode' NT response to the challenge, or unicode password
+ * @param lm_response ASCII or LANMAN response to the challenge, or password in DOS code page
+ * @param username internal Samba username, for log messages
+ * @param client_username username the client used
+ * @param client_domain domain name the client used (may be mapped)
+ * @param nt_pw MD4 unicode password from our passdb or similar
+ * @param lm_pw LANMAN ASCII password from our passdb or similar
+ * @param user_sess_key User session key
+ * @param lm_sess_key LM session key (first 8 bytes of the LM hash)
+ */
+
+NTSTATUS ntlm_password_check(TALLOC_CTX *mem_ctx,
+			     const DATA_BLOB *challenge,
+			     const DATA_BLOB *lm_response,
+			     const DATA_BLOB *nt_response,
+			     const DATA_BLOB *lm_interactive_password,
+			     const DATA_BLOB *nt_interactive_password,
+			     const char *username, 
+			     const char *client_username, 
+			     const char *client_domain,
+			     const uint8_t *lm_pw, const uint8_t *nt_pw, 
+			     DATA_BLOB *user_sess_key, 
+			     DATA_BLOB *lm_sess_key)
+{
+	static const uint8_t zeros[8];
+	if (nt_pw == NULL) {
+		DEBUG(3,("ntlm_password_check: NO NT password stored for user %s.\n", 
+			 username));
+	}
+
+	if (nt_interactive_password && nt_interactive_password->length && nt_pw) { 
+		if (nt_interactive_password->length != 16) {
+			DEBUG(3,("ntlm_password_check: Interactive logon: Invalid NT password length (%d) supplied for user %s\n", (int)nt_interactive_password->length,
+				 username));
+			return NT_STATUS_WRONG_PASSWORD;
+		}
+
+		if (memcmp(nt_interactive_password->data, nt_pw, 16) == 0) {
+			if (user_sess_key) {
+				*user_sess_key = data_blob(NULL, 16);
+				SMBsesskeygen_ntv1(nt_pw, user_sess_key->data);
+			}
+			return NT_STATUS_OK;
+		} else {
+			DEBUG(3,("ntlm_password_check: Interactive logon: NT password check failed for user %s\n",
+				 username));
+			return NT_STATUS_WRONG_PASSWORD;
+		}
+
+	} else if (lm_interactive_password && lm_interactive_password->length && lm_pw) { 
+		if (lm_interactive_password->length != 16) {
+			DEBUG(3,("ntlm_password_check: Interactive logon: Invalid LANMAN password length (%d) supplied for user %s\n", (int)lm_interactive_password->length,
+				 username));
+			return NT_STATUS_WRONG_PASSWORD;
+		}
+
+		if (!lp_lanman_auth()) {
+			DEBUG(3,("ntlm_password_check: Interactive logon: only LANMAN password supplied for user %s, and LM passwords are disabled!\n",
+				 username));
+			return NT_STATUS_WRONG_PASSWORD;
+		}
+
+		if (memcmp(lm_interactive_password->data, lm_pw, 16) == 0) {
+			return NT_STATUS_OK;
+		} else {
+			DEBUG(3,("ntlm_password_check: Interactive logon: LANMAN password check failed for user %s\n",
+				 username));
+			return NT_STATUS_WRONG_PASSWORD;
+		}
+	}
+
+	/* Check for cleartext netlogon. Used by Exchange 5.5. */
+	if (challenge->length == sizeof(zeros) && 
+	    (memcmp(challenge->data, zeros, challenge->length) == 0 )) {
+
+		DEBUG(4,("ntlm_password_check: checking plaintext passwords for user %s\n",
+			 username));
+		if (nt_pw && nt_response->length) {
+			uint8_t pwhash[16];
+			mdfour(pwhash, nt_response->data, nt_response->length);
+			if (memcmp(pwhash, nt_pw, sizeof(pwhash)) == 0) {
+				return NT_STATUS_OK;
+			} else {
+				DEBUG(3,("ntlm_password_check: NT (Unicode) plaintext password check failed for user %s\n",
+					 username));
+				return NT_STATUS_WRONG_PASSWORD;
+			}
+
+		} else if (!lp_lanman_auth()) {
+			DEBUG(3,("ntlm_password_check: (plaintext password check) LANMAN passwords NOT PERMITTED for user %s\n",
+				 username));
+
+		} else if (lm_pw && lm_response->length) {
+			uint8_t dospwd[14]; 
+			uint8_t p16[16]; 
+			ZERO_STRUCT(dospwd);
+			
+			memcpy(dospwd, lm_response->data, MIN(lm_response->length, sizeof(dospwd)));
+			/* Only the fisrt 14 chars are considered, password need not be null terminated. */
+
+			/* we *might* need to upper-case the string here */
+			E_P16((const uint8_t *)dospwd, p16);
+
+			if (memcmp(p16, lm_pw, sizeof(p16)) == 0) {
+				return NT_STATUS_OK;
+			} else {
+				DEBUG(3,("ntlm_password_check: LANMAN (ASCII) plaintext password check failed for user %s\n",
+					 username));
+				return NT_STATUS_WRONG_PASSWORD;
+			}
+		} else {
+			DEBUG(3, ("Plaintext authentication for user %s attempted, but neither NT nor LM passwords available\n", username));
+			return NT_STATUS_WRONG_PASSWORD;
+		}
+	}
+
+	if (nt_response->length != 0 && nt_response->length < 24) {
+		DEBUG(2,("ntlm_password_check: invalid NT password length (%lu) for user %s\n", 
+			 (unsigned long)nt_response->length, username));		
+	}
+	
+	if (nt_response->length >= 24 && nt_pw) {
+		if (nt_response->length > 24) {
+			/* We have the NT MD4 hash challenge available - see if we can
+			   use it 
+			*/
+			DEBUG(4,("ntlm_password_check: Checking NTLMv2 password with domain [%s]\n", client_domain));
+			if (smb_pwd_check_ntlmv2( nt_response, 
+						  nt_pw, challenge, 
+						  client_username, 
+						  client_domain,
+						  False,
+						  user_sess_key)) {
+				return NT_STATUS_OK;
+			}
+			
+			DEBUG(4,("ntlm_password_check: Checking NTLMv2 password with uppercased version of domain [%s]\n", client_domain));
+			if (smb_pwd_check_ntlmv2( nt_response, 
+						  nt_pw, challenge, 
+						  client_username, 
+						  client_domain,
+						  True,
+						  user_sess_key)) {
+				return NT_STATUS_OK;
+			}
+			
+			DEBUG(4,("ntlm_password_check: Checking NTLMv2 password without a domain\n"));
+			if (smb_pwd_check_ntlmv2( nt_response, 
+						  nt_pw, challenge, 
+						  client_username, 
+						  "",
+						  False,
+						  user_sess_key)) {
+				return NT_STATUS_OK;
+			} else {
+				DEBUG(3,("ntlm_password_check: NTLMv2 password check failed\n"));
+				return NT_STATUS_WRONG_PASSWORD;
+			}
+		}
+
+		if (lp_ntlm_auth()) {		
+			/* We have the NT MD4 hash challenge available - see if we can
+			   use it (ie. does it exist in the smbpasswd file).
+			*/
+			DEBUG(4,("ntlm_password_check: Checking NT MD4 password\n"));
+			if (smb_pwd_check_ntlmv1(nt_response, 
+						 nt_pw, challenge,
+						 user_sess_key)) {
+				/* The LM session key for this response is not very secure, 
+				   so use it only if we otherwise allow LM authentication */
+
+				if (lp_lanman_auth() && lm_pw) {
+					*lm_sess_key = data_blob(lm_pw, 8);
+				}
+				return NT_STATUS_OK;
+			} else {
+				DEBUG(3,("ntlm_password_check: NT MD4 password check failed for user %s\n",
+					 username));
+				return NT_STATUS_WRONG_PASSWORD;
+			}
+		} else {
+			DEBUG(2,("ntlm_password_check: NTLMv1 passwords NOT PERMITTED for user %s\n",
+				 username));			
+			/* no return, becouse we might pick up LMv2 in the LM field */
+		}
+	}
+	
+	if (lm_response->length == 0) {
+		DEBUG(3,("ntlm_password_check: NEITHER LanMan nor NT password supplied for user %s\n",
+			 username));
+		return NT_STATUS_WRONG_PASSWORD;
+	}
+	
+	if (lm_response->length < 24) {
+		DEBUG(2,("ntlm_password_check: invalid LanMan password length (%lu) for user %s\n", 
+			 (unsigned long)nt_response->length, username));		
+		return NT_STATUS_WRONG_PASSWORD;
+	}
+		
+	if (!lp_lanman_auth()) {
+		DEBUG(3,("ntlm_password_check: Lanman passwords NOT PERMITTED for user %s\n",
+			 username));
+	} else if (!lm_pw) {
+		DEBUG(3,("ntlm_password_check: NO LanMan password set for user %s (and no NT password supplied)\n",
+			 username));
+	} else {
+		DEBUG(4,("ntlm_password_check: Checking LM password\n"));
+		if (smb_pwd_check_ntlmv1(lm_response, 
+					 lm_pw, challenge,
+					 NULL)) {
+			/* The session key for this response is still very odd.  
+			   It not very secure, so use it only if we otherwise 
+			   allow LM authentication */
+
+			if (lp_lanman_auth() && lm_pw) {
+				uint8_t first_8_lm_hash[16];
+				memcpy(first_8_lm_hash, lm_pw, 8);
+				memset(first_8_lm_hash + 8, '\0', 8);
+				*user_sess_key = data_blob(first_8_lm_hash, 16);
+				*lm_sess_key = data_blob(lm_pw, 8);
+			}
+			return NT_STATUS_OK;
+		}
+	}
+	
+	if (!nt_pw) {
+		DEBUG(4,("ntlm_password_check: LM password check failed for user, no NT password %s\n",username));
+		return NT_STATUS_WRONG_PASSWORD;
+	}
+	
+	/* This is for 'LMv2' authentication.  almost NTLMv2 but limited to 24 bytes.
+	   - related to Win9X, legacy NAS pass-though authentication
+	*/
+	DEBUG(4,("ntlm_password_check: Checking LMv2 password with domain %s\n", client_domain));
+	if (smb_pwd_check_ntlmv2( lm_response, 
+				  nt_pw, challenge, 
+				  client_username,
+				  client_domain,
+				  False,
+				  NULL)) {
+		return NT_STATUS_OK;
+	}
+	
+	DEBUG(4,("ntlm_password_check: Checking LMv2 password with upper-cased version of domain %s\n", client_domain));
+	if (smb_pwd_check_ntlmv2( lm_response, 
+				  nt_pw, challenge, 
+				  client_username,
+				  client_domain,
+				  True,
+				  NULL)) {
+		return NT_STATUS_OK;
+	}
+	
+	DEBUG(4,("ntlm_password_check: Checking LMv2 password without a domain\n"));
+	if (smb_pwd_check_ntlmv2( lm_response, 
+				  nt_pw, challenge, 
+				  client_username,
+				  "",
+				  False,
+				  NULL)) {
+		return NT_STATUS_OK;
+	}
+
+	/* Apparently NT accepts NT responses in the LM field
+	   - I think this is related to Win9X pass-though authentication
+	*/
+	DEBUG(4,("ntlm_password_check: Checking NT MD4 password in LM field\n"));
+	if (lp_ntlm_auth()) {
+		if (smb_pwd_check_ntlmv1(lm_response, 
+					 nt_pw, challenge,
+					 NULL)) {
+			/* The session key for this response is still very odd.  
+			   It not very secure, so use it only if we otherwise 
+			   allow LM authentication */
+
+			if (lp_lanman_auth() && lm_pw) {
+				uint8_t first_8_lm_hash[16];
+				memcpy(first_8_lm_hash, lm_pw, 8);
+				memset(first_8_lm_hash + 8, '\0', 8);
+				*user_sess_key = data_blob(first_8_lm_hash, 16);
+				*lm_sess_key = data_blob(lm_pw, 8);
+			}
+			return NT_STATUS_OK;
+		}
+		DEBUG(3,("ntlm_password_check: LM password, NT MD4 password in LM field and LMv2 failed for user %s\n",username));
+	} else {
+		DEBUG(3,("ntlm_password_check: LM password and LMv2 failed for user %s, and NT MD4 password in LM field not permitted\n",username));
+	}
+	return NT_STATUS_WRONG_PASSWORD;
+}
+