docs/htmldocs/smbpasswd.5.html

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  16 ><H1
  17 ><A
  18 NAME="SMBPASSWD"
  19 ></A
  20 >smbpasswd</H1
  21 ><DIV
  22 CLASS="REFNAMEDIV"
  23 ><A
  24 NAME="AEN5"
  25 ></A
  26 ><H2
  27 >Name</H2
  28 >smbpasswd&nbsp;--&nbsp;The Samba encrypted password file</DIV
  29 ><DIV
  30 CLASS="REFSYNOPSISDIV"
  31 ><A
  32 NAME="AEN8"
  33 ></A
  34 ><H2
  35 >Synopsis</H2
  36 ><P
  37 ><TT
  38 CLASS="FILENAME"
  39 >smbpasswd</TT
  40 ></P
  41 ></DIV
  42 ><DIV
  43 CLASS="REFSECT1"
  44 ><A
  45 NAME="AEN11"
  46 ></A
  47 ><H2
  48 >DESCRIPTION</H2
  49 ><P
  50 >This tool is part of the <A
  51 HREF="samba.7.html"
  52 TARGET="_top"
  53 >       Samba</A
  54 > suite.</P
  55 ><P
  56 >smbpasswd is the Samba encrypted password file. It contains
  57         the username, Unix user id and the SMB hashed passwords of the
  58         user, as well as account flag information and the time the
  59         password was last changed. This file format has been evolving with
  60         Samba and has had several different formats in the past. </P
  61 ></DIV
  62 ><DIV
  63 CLASS="REFSECT1"
  64 ><A
  65 NAME="AEN16"
  66 ></A
  67 ><H2
  68 >FILE FORMAT</H2
  69 ><P
  70 >The format of the smbpasswd file used by Samba 2.2
  71         is very similar to the familiar Unix <TT
  72 CLASS="FILENAME"
  73 >passwd(5)</TT
  74 >
  75         file. It is an ASCII file containing one line for each user. Each field
  76         ithin each line is separated from the next by a colon. Any entry
  77         beginning with '#' is ignored. The smbpasswd file contains the
  78         following information for each user: </P
  79 ><P
  80 ></P
  81 ><DIV
  82 CLASS="VARIABLELIST"
  83 ><DL
  84 ><DT
  85 >name</DT
  86 ><DD
  87 ><P
  88 > This is the user name. It must be a name that
  89                 already exists in the standard UNIX passwd file. </P
  90 ></DD
  91 ><DT
  92 >uid</DT
  93 ><DD
  94 ><P
  95 >This is the UNIX uid. It must match the uid
  96                 field for the same user entry in the standard UNIX passwd file.
  97                 If this does not match then Samba will refuse to recognize
  98                 this smbpasswd file entry as being valid for a user.
  99                 </P
 100 ></DD
 101 ><DT
 102 >Lanman Password Hash</DT
 103 ><DD
 104 ><P
 105 >This is the LANMAN hash of the user's password,
 106                 encoded as 32 hex digits.  The LANMAN hash is created by DES
 107                 encrypting a well known string with the user's password as the
 108                 DES key. This is the same password used by Windows 95/98 machines.
 109                 Note that this password hash is regarded as weak as it is
 110                 vulnerable to dictionary attacks and if two users choose the
 111                 same password this entry will be identical (i.e. the password
 112                 is not "salted" as the UNIX password is). If the user has a
 113                 null password this field will contain the characters "NO PASSWORD"
 114                 as the start of the hex string. If the hex string is equal to
 115                 32 'X' characters then the user's account is marked as
 116                 <TT
 117 CLASS="CONSTANT"
 118 >disabled</TT
 119 > and the user will not be able to
 120                 log onto the Samba server. </P
 121 ><P
 122 ><SPAN
 123 CLASS="emphasis"
 124 ><I
 125 CLASS="EMPHASIS"
 126 >WARNING !!</I
 127 ></SPAN
 128 > Note that, due to
 129                 the challenge-response nature of the SMB/CIFS authentication
 130                 protocol, anyone with a knowledge of this password hash will
 131                 be able to impersonate the user on the network. For this
 132                 reason these hashes are known as <SPAN
 133 CLASS="emphasis"
 134 ><I
 135 CLASS="EMPHASIS"
 136 >plain text
 137                 equivalents</I
 138 ></SPAN
 139 > and must <SPAN
 140 CLASS="emphasis"
 141 ><I
 142 CLASS="EMPHASIS"
 143 >NOT</I
 144 ></SPAN
 145 > be made
 146                 available to anyone but the root user. To protect these passwords
 147                 the smbpasswd file is placed in a directory with read and
 148                 traverse access only to the root user and the smbpasswd file
 149                 itself must be set to be read/write only by root, with no
 150                 other access. </P
 151 ></DD
 152 ><DT
 153 >NT Password Hash</DT
 154 ><DD
 155 ><P
 156 >This is the Windows NT hash of the user's
 157                 password, encoded as 32 hex digits.  The Windows NT hash is
 158                 created by taking the user's password as represented in
 159                 16-bit, little-endian UNICODE and then applying the MD4
 160                 (internet rfc1321) hashing algorithm to it. </P
 161 ><P
 162 >This password hash is considered more secure than
 163                 the LANMAN Password Hash as it preserves the case of the
 164                 password and uses a much higher quality hashing algorithm.
 165                 However, it is still the case that if two users choose the same
 166                 password this entry will be identical (i.e. the password is
 167                 not "salted" as the UNIX password is). </P
 168 ><P
 169 ><SPAN
 170 CLASS="emphasis"
 171 ><I
 172 CLASS="EMPHASIS"
 173 >WARNING !!</I
 174 ></SPAN
 175 >. Note that, due to
 176                 the challenge-response nature of the SMB/CIFS authentication
 177                 protocol, anyone with a knowledge of this password hash will
 178                 be able to impersonate the user on the network. For this
 179                 reason these hashes are known as <SPAN
 180 CLASS="emphasis"
 181 ><I
 182 CLASS="EMPHASIS"
 183 >plain text
 184                 equivalents</I
 185 ></SPAN
 186 > and must <SPAN
 187 CLASS="emphasis"
 188 ><I
 189 CLASS="EMPHASIS"
 190 >NOT</I
 191 ></SPAN
 192 > be made
 193                 available to anyone but the root user. To protect these passwords
 194                 the smbpasswd file is placed in a directory with read and
 195                 traverse access only to the root user and the smbpasswd file
 196                 itself must be set to be read/write only by root, with no
 197                 other access. </P
 198 ></DD
 199 ><DT
 200 >Account Flags</DT
 201 ><DD
 202 ><P
 203 >This section contains flags that describe
 204                 the attributes of the users account. In the Samba 2.2 release
 205                 this field is bracketed by '[' and ']' characters and is always
 206                 13 characters in length (including the '[' and ']' characters).
 207                 The contents of this field may be any of the characters.
 208                 </P
 209 ><P
 210 ></P
 211 ><UL
 212 ><LI
 213 ><P
 214 ><SPAN
 215 CLASS="emphasis"
 216 ><I
 217 CLASS="EMPHASIS"
 218 >U</I
 219 ></SPAN
 220 > - This means
 221                         this is a "User" account, i.e. an ordinary user. Only User
 222                         and Workstation Trust accounts are currently supported
 223                         in the smbpasswd file. </P
 224 ></LI
 225 ><LI
 226 ><P
 227 ><SPAN
 228 CLASS="emphasis"
 229 ><I
 230 CLASS="EMPHASIS"
 231 >N</I
 232 ></SPAN
 233 > - This means the
 234                         account has no password (the passwords in the fields LANMAN
 235                         Password Hash and NT Password Hash are ignored). Note that this
 236                         will only allow users to log on with no password if the <TT
 237 CLASS="PARAMETER"
 238 ><I
 239 >                       null passwords</I
 240 ></TT
 241 > parameter is set in the <A
 242 HREF="smb.conf.5.html#NULLPASSWORDS"
 243 TARGET="_top"
 244 ><TT
 245 CLASS="FILENAME"
 246 >smb.conf(5)
 247                         </TT
 248 ></A
 249 > config file. </P
 250 ></LI
 251 ><LI
 252 ><P
 253 ><SPAN
 254 CLASS="emphasis"
 255 ><I
 256 CLASS="EMPHASIS"
 257 >D</I
 258 ></SPAN
 259 > - This means the account
 260                         is disabled and no SMB/CIFS logins  will be     allowed for
 261                         this user. </P
 262 ></LI
 263 ><LI
 264 ><P
 265 ><SPAN
 266 CLASS="emphasis"
 267 ><I
 268 CLASS="EMPHASIS"
 269 >W</I
 270 ></SPAN
 271 > - This means this account
 272                         is a "Workstation Trust" account. This kind of account is used
 273                         in the Samba PDC code stream to allow Windows NT Workstations
 274                         and Servers to join a Domain hosted by a Samba PDC. </P
 275 ></LI
 276 ></UL
 277 ><P
 278 >Other flags may be added as the code is extended in future.
 279                 The rest of this field space is filled in with spaces. </P
 280 ></DD
 281 ><DT
 282 >Last Change Time</DT
 283 ><DD
 284 ><P
 285 >This field consists of the time the account was
 286                 last modified. It consists of the characters 'LCT-' (standing for
 287                 "Last Change Time") followed by a numeric encoding of the UNIX time
 288                 in seconds since the epoch (1970) that the last change was made.
 289                 </P
 290 ></DD
 291 ></DL
 292 ></DIV
 293 ><P
 294 >All other colon separated fields are ignored at this time.</P
 295 ></DIV
 296 ><DIV
 297 CLASS="REFSECT1"
 298 ><A
 299 NAME="AEN73"
 300 ></A
 301 ><H2
 302 >VERSION</H2
 303 ><P
 304 >This man page is correct for version 3.0 of
 305         the Samba suite.</P
 306 ></DIV
 307 ><DIV
 308 CLASS="REFSECT1"
 309 ><A
 310 NAME="AEN76"
 311 ></A
 312 ><H2
 313 >SEE ALSO</H2
 314 ><P
 315 ><A
 316 HREF="smbpasswd.8.html"
 317 TARGET="_top"
 318 ><B
 319 CLASS="COMMAND"
 320 >smbpasswd(8)</B
 321 ></A
 322 >,
 323         <A
 324 HREF="samba.7.html"
 325 TARGET="_top"
 326 >samba(7)</A
 327 >, and
 328         the Internet RFC1321 for details on the MD4 algorithm.
 329         </P
 330 ></DIV
 331 ><DIV
 332 CLASS="REFSECT1"
 333 ><A
 334 NAME="AEN82"
 335 ></A
 336 ><H2
 337 >AUTHOR</H2
 338 ><P
 339 >The original Samba software and related utilities
 340         were created by Andrew Tridgell. Samba is now developed
 341         by the Samba Team as an Open Source project similar
 342         to the way the Linux kernel is developed.</P
 343 ><P
 344 >The original Samba man pages were written by Karl Auer.
 345         The man page sources were converted to YODL format (another
 346         excellent piece of Open Source software, available at
 347         <A
 348 HREF="ftp://ftp.icce.rug.nl/pub/unix/"
 349 TARGET="_top"
 350 >       ftp://ftp.icce.rug.nl/pub/unix/</A
 351 >) and updated for the Samba 2.0
 352         release by Jeremy Allison.  The conversion to DocBook for
 353         Samba 2.2 was done by Gerald Carter</P
 354 ></DIV
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