source/lib/passcheck.c

   1 /*
   2    Unix SMB/Netbios implementation.
   3    Version 1.9.
   4    Password and authentication handling
   5    Copyright (C) Andrew Tridgell              1992-2000
   6    Copyright (C) Luke Kenneth Casson Leighton 1996-2000
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 2 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program; if not, write to the Free Software
  20    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  21 */
  22
  23 #include "includes.h"
  24
  25 extern int DEBUGLEVEL;
  26
  27
  28 /****************************************************************************
  29 core of smb password checking routine.
  30 ****************************************************************************/
  31 static BOOL smb_pwd_check_ntlmv1(const char *password,
  32                                 const uchar *part_passwd,
  33                                 const uchar *c8,
  34                                 uchar user_sess_key[16])
  35 {
  36   /* Finish the encryption of part_passwd. */
  37   uchar p24[24];
  38
  39   if (part_passwd == NULL)
  40     DEBUG(10,("No password set - allowing access\n"));
  41   /* No password set - always true ! */
  42   if (part_passwd == NULL)
  43     return True;
  44
  45   SMBOWFencrypt(part_passwd, c8, p24);
  46         if (user_sess_key != NULL)
  47         {
  48                 SMBsesskeygen_ntv1(part_passwd, NULL, user_sess_key);
  49         }
  50
  51 #if DEBUG_PASSWORD
  52         DEBUG(100,("Part password (P16) was |"));
  53         dump_data(100, part_passwd, 16);
  54         DEBUG(100,("Password from client was |"));
  55         dump_data(100, password, 24);
  56         DEBUG(100,("Given challenge was |"));
  57         dump_data(100, c8, 8);
  58         DEBUG(100,("Value from encryption was |"));
  59         dump_data(100, p24, 24);
  60 #endif
  61   return (memcmp(p24, password, 24) == 0);
  62 }
  63
  64 /****************************************************************************
  65 core of smb password checking routine.
  66 ****************************************************************************/
  67 static BOOL smb_pwd_check_ntlmv2(const char *password, size_t pwd_len,
  68                                 uchar *part_passwd,
  69                                 uchar const *c8,
  70                                 const char *user, const char *domain,
  71                                 char *user_sess_key)
  72 {
  73         /* Finish the encryption of part_passwd. */
  74         uchar kr[16];
  75         uchar resp[16];
  76
  77         if (part_passwd == NULL)
  78         {
  79                 DEBUG(10,("No password set - allowing access\n"));
  80         }
  81         /* No password set - always true ! */
  82         if (part_passwd == NULL)
  83         {
  84                 return True;
  85         }
  86
  87         ntv2_owf_gen(part_passwd, user, domain, kr);
  88         SMBOWFencrypt_ntv2(kr, c8, 8, password+16, pwd_len-16, resp);
  89         if (user_sess_key != NULL)
  90         {
  91                 SMBsesskeygen_ntv2(kr, resp, user_sess_key);
  92         }
  93
  94 #if DEBUG_PASSWORD
  95         DEBUG(100,("Part password (P16) was |"));
  96         dump_data(100, part_passwd, 16);
  97         DEBUG(100,("Password from client was |"));
  98         dump_data(100, password, pwd_len);
  99         DEBUG(100,("Given challenge was |"));
 100         dump_data(100, c8, 8);
 101         DEBUG(100,("Value from encryption was |"));
 102         dump_data(100, resp, 16);
 103 #endif
 104
 105         return (memcmp(resp, password, 16) == 0);
 106 }
 107
 108 /****************************************************************************
 109  Do a specific test for an smb password being correct, given a smb_password and
 110  the lanman and NT responses.
 111 ****************************************************************************/
 112 BOOL smb_password_ok(uint16 acct_ctrl,
 113                                 uchar smb_passwd[16],
 114                                 uchar smb_nt_passwd[16],
 115                                 const uchar challenge[8],
 116                                 const char *user, const char *domain,
 117                                 const uchar *lm_pass, size_t lm_pwd_len,
 118                                 const uchar *nt_pass, size_t nt_pwd_len,
 119                                 uchar user_sess_key[16])
 120 {
 121         DEBUG(4,("Checking SMB password for user %s\n", user));
 122
 123         dump_data_pw("lm password:\n", lm_pass, lm_pwd_len);
 124         dump_data_pw("nt password:\n", nt_pass, nt_pwd_len);
 125
 126         if (acct_ctrl & ACB_DISABLED)
 127         {
 128                 DEBUG(3,("account for user %s was disabled.\n", user));
 129                 return False;
 130         }
 131
 132         if (challenge == NULL)
 133         {
 134                 DEBUG(1,("no challenge available - password failed\n"));
 135                 return False;
 136         }
 137
 138         if (smb_nt_passwd != NULL)
 139         {
 140                 /* We have the NT MD4 hash challenge available - see if we can
 141                    use it (ie. does it exist in the smbpasswd file).
 142                 */
 143                 if (lp_server_ntlmv2() != False && nt_pwd_len > 24)
 144                 {
 145                         DEBUG(4,("smb_password_ok: Check NTLMv2 password\n"));
 146                         if (smb_pwd_check_ntlmv2(nt_pass, nt_pwd_len,
 147                                        (uchar *)smb_nt_passwd,
 148                                         challenge, user, domain,
 149                                         user_sess_key))
 150                         {
 151                                 return True;
 152                         }
 153                 }
 154                 if (lp_server_ntlmv2() != True && nt_pwd_len == 24)
 155                 {
 156                         DEBUG(4,("smb_password_ok: Check NT MD4 password\n"));
 157                         if (smb_pwd_check_ntlmv1((const char *)nt_pass,
 158                                        (const uchar *)smb_nt_passwd,
 159                                        challenge,
 160                                        user_sess_key))
 161                         {
 162                                 DEBUG(4,("NT MD4 password check succeeded\n"));
 163                                 return True;
 164                         }
 165                 }
 166                 DEBUG(4,("NT MD4 password check failed\n"));
 167         }
 168
 169         if (lp_server_ntlmv2() == True)
 170         {
 171                 DEBUG(4,("Not checking LM MD4 password\n"));
 172                 return False;
 173         }
 174
 175         /* Try against the lanman password. smb_passwd == NULL means
 176            no password, allow access. */
 177
 178         DEBUG(4,("Checking LM MD4 password\n"));
 179
 180         if ((smb_passwd == NULL) &&
 181            (acct_ctrl & ACB_PWNOTREQ))
 182         {
 183                 DEBUG(4,("no password required for user %s\n", user));
 184                 return True;
 185         }
 186
 187         if ((smb_passwd != NULL) &&
 188            smb_pwd_check_ntlmv1((const char *)lm_pass,
 189                               (const uchar *)smb_passwd,
 190                                 challenge, user_sess_key))
 191         {
 192                 DEBUG(4,("LM MD4 password check succeeded\n"));
 193                 return(True);
 194         }
 195
 196         DEBUG(4,("LM MD4 password check failed\n"));
 197
 198         return False;
 199 }
 200