.\" XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX .\" DO NOT EDIT! Generated from XML source. .\" XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX .de Sh \" Subsection .br .if t .Sp .ne 5 .PP \fB\\$1\fR .PP .. .de Sp \" Vertical space (when we can't use .PP) .if t .sp .5v .if n .sp .. .de Ip \" List item .br .ie \\n(.$>=3 .ne \\$3 .el .ne 3 .IP "\\$1" \\$2 .. .TH "HTDBM" 1 "2024-04-02" "Apache HTTP Server" "htdbm" .SH NAME htdbm \- Manipulate DBM password databases .SH "SYNOPSIS" .PP \fB\fBhtdbm\fR [ -\fBT\fR\fIDBTYPE\fR ] [ -\fBi\fR ] [ -\fBc\fR ] [ -\fBm\fR | -\fBB\fR | -\fBd\fR | -\fBs\fR | -\fBp\fR ] [ -\fBC\fR \fIcost\fR ] [ -\fBt\fR ] [ -\fBv\fR ] \fIfilename\fR \fIusername\fR\fR .PP \fB\fBhtdbm\fR -\fBb\fR [ -\fBT\fR\fIDBTYPE\fR ] [ -\fBc\fR ] [ -\fBm\fR | -\fBB\fR | -\fBd\fR | -\fBs\fR | -\fBp\fR ] [ -\fBC\fR \fIcost\fR ] [ -\fBt\fR ] [ -\fBv\fR ] \fIfilename\fR \fIusername\fR \fIpassword\fR\fR .PP \fB\fBhtdbm\fR -\fBn\fR [ -\fBi\fR ] [ -\fBc\fR ] [ -\fBm\fR | -\fBB\fR | -\fBd\fR | -\fBs\fR | -\fBp\fR ] [ -\fBC\fR \fIcost\fR ] [ -\fBt\fR ] [ -\fBv\fR ] \fIusername\fR\fR .PP \fB\fBhtdbm\fR -\fBnb\fR [ -\fBc\fR ] [ -\fBm\fR | -\fBB\fR | -\fBd\fR | -\fBs\fR | -\fBp\fR ] [ -\fBC\fR \fIcost\fR ] [ -\fBt\fR ] [ -\fBv\fR ] \fIusername\fR \fIpassword\fR\fR .PP \fB\fBhtdbm\fR -\fBv\fR [ -\fBT\fR\fIDBTYPE\fR ] [ -\fBi\fR ] [ -\fBc\fR ] [ -\fBm\fR | -\fBB\fR | -\fBd\fR | -\fBs\fR | -\fBp\fR ] [ -\fBC\fR \fIcost\fR ] [ -\fBt\fR ] [ -\fBv\fR ] \fIfilename\fR \fIusername\fR\fR .PP \fB\fBhtdbm\fR -\fBvb\fR [ -\fBT\fR\fIDBTYPE\fR ] [ -\fBc\fR ] [ -\fBm\fR | -\fBB\fR | -\fBd\fR | -\fBs\fR | -\fBp\fR ] [ -\fBC\fR \fIcost\fR ] [ -\fBt\fR ] [ -\fBv\fR ] \fIfilename\fR \fIusername\fR \fIpassword\fR\fR .PP \fB\fBhtdbm\fR -\fBx\fR [ -\fBT\fR\fIDBTYPE\fR ] \fIfilename\fR \fIusername\fR\fR .PP \fB\fBhtdbm\fR -\fBl\fR [ -\fBT\fR\fIDBTYPE\fR ] \fR .SH "SUMMARY" .PP \fBhtdbm\fR is used to manipulate the DBM format files used to store usernames and password for basic authentication of HTTP users via mod_authn_dbm\&. See the dbmmanage documentation for more information about these DBM files\&. .SH "OPTIONS" .TP \fB-b\fR Use batch mode; \fIi\&.e\&.\fR, get the password from the command line rather than prompting for it\&. This option should be used with extreme care, since \fBthe password is clearly visible\fR on the command line\&. For script use see the \fB-i\fR option\&. .TP \fB-i\fR Read the password from stdin without verification (for script usage)\&. .TP \fB-c\fR Create the \fIpasswdfile\fR\&. If \fIpasswdfile\fR already exists, it is rewritten and truncated\&. This option cannot be combined with the \fB-n\fR option\&. .TP \fB-n\fR Display the results on standard output rather than updating a database\&. This option changes the syntax of the command line, since the \fIpasswdfile\fR argument (usually the first one) is omitted\&. It cannot be combined with the \fB-c\fR option\&. .TP \fB-m\fR Use MD5 hashing for passwords\&. On Windows and Netware, this is the default\&. .TP \fB-B\fR Use bcrypt hashing for passwords\&. This is currently considered to be very secure\&. .TP \fB-C\fR This flag is only allowed in combination with \fB-B\fR (bcrypt hashing)\&. It sets the computing time used for the bcrypt algorithm (higher is more secure but slower, default: 5, valid: 4 to 31)\&. .TP \fB-d\fR Use \fBcrypt()\fR hashing for passwords\&. The default on all platforms but Windows and Netware\&. Though possibly supported by \fBhtdbm\fR on all platforms, it is not supported by the httpd server on Windows and Netware\&. This algorithm is \fBinsecure\fR by today's standards\&. .TP \fB-s\fR Use SHA hashing for passwords\&. Facilitates migration from/to Netscape servers using the LDAP Directory Interchange Format (ldif)\&. This algorithm is \fBinsecure\fR by today's standards\&. .TP \fB-p\fR Use plaintext passwords\&. Though \fBhtdbm\fR will support creation on all platforms, the httpd daemon will only accept plain text passwords on Windows and Netware\&. .TP \fB-l\fR Print each of the usernames and comments from the database on stdout\&. .TP \fB-v\fR Verify the username and password\&. The program will print a message indicating whether the supplied password is valid\&. If the password is invalid, the program exits with error code 3\&. .TP \fB-x\fR Delete user\&. If the username exists in the specified DBM file, it will be deleted\&. .TP \fB-t\fR Interpret the final parameter as a comment\&. When this option is specified, an additional string can be appended to the command line; this string will be stored in the "Comment" field of the database, associated with the specified username\&. .TP \fB\fIfilename\fR\fR The filename of the DBM format file\&. Usually without the extension \fB\&.db\fR, \fB\&.pag\fR, or \fB\&.dir\fR\&. If \fB-c\fR is given, the DBM file is created if it does not already exist, or updated if it does exist\&. .TP \fB\fIusername\fR\fR The username to create or update in \fIpasswdfile\fR\&. If \fIusername\fR does not exist in this file, an entry is added\&. If it does exist, the password is changed\&. .TP \fB\fIpassword\fR\fR The plaintext password to be hashed and stored in the DBM file\&. Used only with the \fB-b\fR flag\&. .TP \fB-T\fIDBTYPE\fR\fR Type of DBM file (SDBM, GDBM, DB, or "default")\&. .SH "BUGS" .PP One should be aware that there are a number of different DBM file formats in existence, and with all likelihood, libraries for more than one format may exist on your system\&. The three primary examples are SDBM, NDBM, GNU GDBM, and Berkeley/Sleepycat DB 2/3/4\&. Unfortunately, all these libraries use different file formats, and you must make sure that the file format used by \fIfilename\fR is the same format that \fBhtdbm\fR expects to see\&. \fBhtdbm\fR currently has no way of determining what type of DBM file it is looking at\&. If used against the wrong format, will simply return nothing, or may create a different DBM file with a different name, or at worst, it may corrupt the DBM file if you were attempting to write to it\&. .PP One can usually use the \fBfile\fR program supplied with most Unix systems to see what format a DBM file is in\&. .SH "EXIT STATUS" .PP \fBhtdbm\fR returns a zero status ("true") if the username and password have been successfully added or updated in the DBM File\&. \fBhtdbm\fR returns \fB1\fR if it encounters some problem accessing files, \fB2\fR if there was a syntax problem with the command line, \fB3\fR if the password was entered interactively and the verification entry didn't match, \fB4\fR if its operation was interrupted, \fB5\fR if a value is too long (username, filename, password, or final computed record), \fB6\fR if the username contains illegal characters (see the Restrictions section), and \fB7\fR if the file is not a valid DBM password file\&. .SH "EXAMPLES" .nf htdbm /usr/local/etc/apache/\&.htdbm-users jsmith .fi .PP Adds or modifies the password for user \fBjsmith\fR\&. The user is prompted for the password\&. If executed on a Windows system, the password will be hashed using the modified Apache MD5 algorithm; otherwise, the system's \fBcrypt()\fR routine will be used\&. If the file does not exist, \fBhtdbm\fR will do nothing except return an error\&. .nf htdbm -c /home/doe/public_html/\&.htdbm jane .fi .PP Creates a new file and stores a record in it for user \fBjane\fR\&. The user is prompted for the password\&. If the file exists and cannot be read, or cannot be written, it is not altered and \fBhtdbm\fR will display a message and return an error status\&. .nf htdbm -mb /usr/web/\&.htdbm-all jones Pwd4Steve .fi .PP Encrypts the password from the command line (\fBPwd4Steve\fR) using the MD5 algorithm, and stores it in the specified file\&. .SH "SECURITY CONSIDERATIONS" .PP Web password files such as those managed by \fBhtdbm\fR should \fInot\fR be within the Web server's URI space -- that is, they should not be fetchable with a browser\&. .PP The use of the \fB-b\fR option is discouraged, since when it is used the plaintext password appears on the command line\&. .PP When using the \fBcrypt()\fR algorithm, note that only the first 8 characters of the password are used to form the password\&. If the supplied password is longer, the extra characters will be silently discarded\&. .PP The SHA hashing option does not use salting: for a given password, there is only one hashed representation\&. The \fBcrypt()\fR and MD5 formats permute the representation by prepending a random salt string, to make dictionary attacks against the passwords more difficult\&. .PP The SHA and \fBcrypt()\fR formats are insecure by today's standards\&. .SH "RESTRICTIONS" .PP On the Windows platform, passwords hashed with \fBhtdbm\fR are limited to no more than \fB255\fR characters in length\&. Longer passwords will be truncated to 255 characters\&. .PP The MD5 algorithm used by \fBhtdbm\fR is specific to the Apache software; passwords hashed using it will not be usable with other Web servers\&. .PP Usernames are limited to \fB255\fR bytes and may not include the character \fB:\fR\&.