BOZOHTTPD(8)

BOZOHTTPD(8) | System Manager's Manual | BOZOHTTPD(8)

# NAME

`bozohttpd` —
hyper text transfer protocol version 1.1 daemon

# SYNOPSIS

`bozohttpd` | [`-EGHVXdefhnsu`] [`-C` suffix cgihandler] [`-I` port] [`-L` prefix script] [`-M` suffix type encoding encoding11] [`-P` pidfile] [`-R` readme] [`-S` version] [`-T` type timeout] [`-U` username] [`-Z` cert privkey] [`-c` cgibin] [`-i` address] [`-p` pubdir] [`-t` chrootdir] [`-v` virtualroot] [`-x` index] [`-z` ciphers] slashdir [myname]

# DESCRIPTION

The `bozohttpd` program reads a HTTP request from the standard input, and sends a reply to the standard output. Besides ~user translation and virtual hosting support (see below), all file requests are from slashdir directory. The server uses myname as its name, which defaults to the local hostname, obtained from gethostname(3) (but see the `-v` option for virtual hosting.) `bozohttpd` writes logs to syslog(3) using the ftp facility (but see the `-s` option for testing.) `bozohttpd` is designed to be small, simple and relatively featureless, hopefully increasing its security.

## OPTIONS

The following options are available:

`-b`
  Enables daemon mode, where `bozohttpd` detaches from the current terminal, running in the background and servicing HTTP requests.
`-C` suffix cgihandler
  Adds a new CGI handler program for a particular file type. The suffix should be any normal file suffix, and the cgihandler should be a full path to an interpreter. This option is the only way to enable CGI programs that exist outside of the cgibin directory to be executed. Multiple `-C` options may be passed.
`-c` cgibin
  Enables the CGI/1.1 interface. The cgibin directory is expected to contain the CGI programs to be used. `bozohttpd` looks for URL's in the form of /cgi-bin/<scriptname> where ⟨scriptname⟩ is a valid CGI program in the cgibin directory. In other words, all CGI URL's must begin with /cgi-bin/. Note that the CGI/1.1 interface is available with ~user translation using `-E` switch.
`-d`
  Enables debug support.
`-E`
  Enables CGI/1.1 interface for ~user translation. Note that enabling this support implies that users can run commands as the web server user. This may have security implications.
`-e`
  Causes `bozohttpd` to not clear the environment when used with either the `-t` or `-U` options.
`-f`
  Stops the `-b` flag from detaching `bozohttpd` from the tty and going into the background. This implies the `-b` flag.
`-G`
  Get the `bozohttpd` version string, print it on standard output, and exit.
`-H`
  Causes directory index mode to hide files and directories that start with a period, except for ... Also see `-X`.
`-I` port
  Causes `bozohttpd` to use port instead of the default “http” port. When used with the `-b` option, it changes the bound port. Otherwise it forces redirections to use this port instead of the value obtained via getsockname(2).
`-i` address
  Causes address to be used as the address to bind daemon mode. If otherwise unspecified, the address used to bind is derived from the myname, which defaults to the name returned by gethostname(3). Only the last `-i` option is used. This option is only valid with the `-b` option.
`-L` prefix script
  Adds a new Lua script for a particular prefix. The prefix should be an arbitrary text, and the script should be a full path to a Lua script. Multiple `-L` options may be passed. A separate Lua state is created for each prefix. The Lua script can register callbacks using the httpd.register_handler('<name>', function) Lua function, which will trigger the execution of the Lua function function when a URL in the form http://<hostname>/<prefix>/<name> is being accessed. The function is passed three tables as arguments, the server environment, the request headers, and the decoded query string plus any data that was sent as application/x-www-form-urlencoded.
`-M` suffix type encoding encoding11
  Adds a new entry to the table that converts file suffixes to content type and encoding. This option takes four additional arguments containing the file prefix, its “Content-Type”, “Content-Encoding”, and “Content-Encoding” for HTTP/1.1 connections, respectively. If any of these are a single dash (“-”), the empty string is used instead. Multiple `-M` options may be passed.
`-n`
  Stops `bozohttpd` from doing IP address to name resolution of remote hosts. This affects the `REMOTE_HOST` environment variable for CGI programs and Lua scripts.
`-P` pidfile
  Causes `bozohttpd` to create a PID file in pidfile when run in daemon mode with the `-b` option.
`-p` pubdir
  Changes the default user directory for /~user/ translations from “public_html” to pubdir.
`-R` readme
  When directory indexing is enabled, include the contents of the file readme in the footer of the directory index.
`-S` version
  Sets the internal server version to version.
`-s`
  Forces logging to be set to stderr always.
`-T` type timeout
  Set the timeout for type to timeout. The valid values of type are “ssl timeout”, “initial timeout”, “header timeout”, and “request timeout”. The default values are 30 seconds, 30 seconds, 10 seconds and 600 seconds, respectively.
`-t` chrootdir
  Makes `bozohttpd` chroot to the specified directory before answering requests. Every other path should be specified relative to the new root, if this option is used. Note that the current environment is normally replaced with an empty environment with this option, unless the `-e` option is also used.
`-U` username
  Causes `bozohttpd` to switch to the user and the groups of username after initialization. This option, like `-t` above, causes `bozohttpd` to clear the environment unless the `-e` option is given.
`-u`
  Enables the transformation of Uniform Resource Locators of the form /~user/ into the directory ~user/public_html (but see the `-p` option above).
`-V`
  Sets the backup virtual host directory to the slashdir argument. If no directory exists in virtualroot for the request, then slashdir will be used. The default behavior is to return 404 (Not Found.)
`-v` virtualroot
  Enables virtual hosting support. Directories in virtualroot will be searched for a matching virtual host name, when parsing the HTML request. If a matching name is found, it will be used as both the server's real name, [myname], and as the slashdir. See the EXAMPLES section for an example of using this option.
`-X`
  Enables directory indexing. A directory index will be generated only when the default file (i.e. index.html normally) is not present.
`-x` index
  Changes the default file read for directories from “index.html” to index.
`-Z` certificate_path privatekey_path
  Sets the path to the server certificate file and the private key file in PEM format. It also causes `bozohttpd` to start SSL mode.
`-z` ciphers
  Sets the list of SSL ciphers (see SSL_CTX_set_cipher_list(3)).

Note that in `bozohttpd` versions 20031005 and prior that supported the `-C` and `-M` options, they took a single space-separated argument that was parsed. since version 20040828, they take multiple options (2 in the case of `-C` and 4 in the case of `-M`.)

## INETD CONFIGURATION

As `bozohttpd` uses inetd(8) by default to process incoming TCP connections for HTTP requests (but see the `-b` option), `bozohttpd` has little internal networking knowledge. (Indeed, you can run it on the command line with little change of functionality.) A typical inetd.conf(5) entry would be:

    http stream tcp  nowait:600 _httpd /usr/libexec/httpd httpd /var/www
    http stream tcp6 nowait:600 _httpd /usr/libexec/httpd httpd /var/www

This would serve web pages from /var/www on both IPv4 and IPv6 ports. The :600 changes the requests per minute to 600, up from the inetd(8) default of 40.

Using the NetBSD inetd(8), you can provide multiple IP-address based HTTP servers by having multiple listening ports with different configurations.

## NOTES

This server supports the HTTP/0.9, HTTP/1.0, and HTTP/1.1 standards. Support for these protocols is very minimal and many optional features are not supported.

`bozohttpd` can be compiled without CGI support (NO_CGIBIN_SUPPORT), user transformations (NO_USER_SUPPORT), directory index support (NO_DIRINDEX_SUPPORT), daemon mode support (NO_DAEMON_MODE), dynamic MIME content (NO_DYNAMIC_CONTENT), Lua support (NO_LUA_SUPPORT), and SSL support (NO_SSL_SUPPORT) by defining the listed macros when building `bozohttpd`.

## HTTP BASIC AUTHORIZATION

`bozohttpd` has support for HTTP Basic Authorization. If a file named .htpasswd exists in the directory of the current request, `bozohttpd` will restrict access to documents in that directory using the RFC 2617 HTTP “Basic” authentication scheme.

Note: This does not recursively protect any sub-directories.

The .htpasswd file contains lines delimited with a colon containing user names and passwords hashed with crypt(3), for example:

    heather:$1$pZWI4tH/$DzDPl63i6VvVRv2lJNV7k1
    jeremy:A.xewbx2DpQ8I

On NetBSD, the pwhash(1) utility may be used to generate hashed passwords.

While `bozohttpd` distributed with NetBSD has support for HTTP Basic Authorization enabled by default, in the portable distribution it is excluded. Compile `bozohttpd` with “-DDO_HTPASSWD” on the compiler command line to enable this support. It may require linking with the crypt library, using “-lcrypt”.

## BLOCKLIST SUPPORT

On NetBSD, `bozohttpd` supports blocklistd(8) by default. The support can be disabled with the “-DNO_BLOCKLIST_SUPPORT” compilation option.

Upon occurrence, `bozohttpd` reports two HTTP status codes to blocklistd(8) as failures: 401 (``Unauthorized'') and 403 (``Forbidden'') . Of these, 401 is the one received upon authorization failure with the HTTP Basic Authorization mechanism. A successful authorization decreases the counter kept by blocklistd(8).

Note that the implementation of the HTTP Basic Authorization mechanism uses a redirection; a status code 401 is always initially received. Therefore, a single authorization failure of .htpasswd is reported as two failures to blocklistd(8), but no failures are recorded upon successful authorization due to the decrease of the failure counter.

## SSL SUPPORT

`bozohttpd` has support for TLSv1.1 and TLSv1.2 protocols that are included by default. It requires linking with the crypto and ssl library, using “-lcrypto -lssl”. To disable SSL SUPPORT compile `bozohttpd` with “-DNO_SSL_SUPPORT” on the compiler command line.

## COMPRESSION

`bozohttpd` supports a very basic form of compression. `bozohttpd` will serve the requested file postpended with “.gz” if it exists, it is readable, the client requested gzip compression, and the client did not make a ranged request.

# FILES

`bozohttpd` looks for a couple of special files in directories that allow certain features to be provided on a per-directory basis. In addition to the .htpasswd used by HTTP basic authorization, if a .bzdirect file is found (contents are irrelevant) `bozohttpd` will allow direct access. If a .bzredirect symbolic link is found, `bozohttpd` will perform a smart redirect to the target of this symlink. The target is assumed to live on the same server. If target starts with slash then absolute redirection is performed, otherwise it's handled as relative. If a .bzabsredirect symbolic link is found, `bozohttpd` will redirect to the absolute URL pointed to by this symlink. This is useful to redirect to different servers. Two forms of redirection are supported - symbolic link without schema will use http:// as default i.e. link to NetBSD.org will redirect to http://NetBSD.org/ Otherwise provided schema will be used i.e. symbolic link to ftp://NetBSD.org/ will redirect to the provided URL. If a .bzremap file is found at the root of a (virtual) server, it is expected to contain rewrite mappings for URLs.

These remappings are performed internally in the server before authentication happens and can be used to hide implementation details, like the CGI handler specific suffix for non cgi scripts in authorized directories.

The map file consists of lines two paths separated by a colon, where the left side needs to exactly match a (sub) path of the request and will be replaced by the right side.

The first match always wins.

A .bzremap file could look like this:

    /nic/update:/auth-dir/updipv4.pl

The remap file should be short, access to it is slow and needs to happen on each request. If a request path needs to include a colon (`:`) character, it can be escaped with a backslash (`\`) The right hand side of the colon is always used verbatim, no escape sequences are interpreted.

# EXAMPLES

To configure set of virtual hosts, one would use an inetd.conf(5) entry like:

    http stream tcp  nowait:600 _httpd /usr/libexec/httpd httpd -v /var/vroot /var/www

and inside /var/vroot create a directory (or a symlink to a directory) with the same name as the virtual host, for each virtual host. Lookups for these names are done in a case-insensitive manner, and may include the port number part of the request, allowing for distinct virtual hosts on the same name.

To use `bozohttpd` with PHP, one must use the `-C` option to specify a CGI handler for a particular file type. Typically this will be like:

    httpd -C .php /usr/pkg/bin/php-cgi /var/www

Note that a plain script interpreter can not be used directly as a cgihandler, as there are no command line options passed from `bozohttpd` to avoid security issues.

If no CGI-aware wrapper exists, a simple shell script like the following might do.

It would be invoked like:

    httpd -C .pl /www-scripts/bin/run.perl /var/www

and the script could look like:

    #! /bin/sh

    if [ -r "$SCRIPT_FILENAME" -a -x "$SCRIPT_FILENAME" ]; then
    	exec /usr/pkg/bin/perl "$SCRIPT_FILENAME"
    fi

    exit 1

# SEE ALSO

inetd.conf(5), inetd(8)

# HISTORY

`bozohttpd` was first written in perl, based on another perl http server called “tinyhttpd”. It was then rewritten from scratch in perl, and then once again in C. From “bozohttpd” version 20060517, it has been integrated into NetBSD. The focus has always been simplicity and security, with minimal features and regular code audits. This manual documents `bozohttpd` version 20210227.

# AUTHORS

`bozohttpd` was written by Matthew R. Green <mrg@eterna.com.au>.

The large list of contributors includes:

- Christoph Badura <bad@bsd.de> provided Range: header support
- Marc Balmer <mbalmer@NetBSD.org> added Lua support for dynamic content creation
- Sean Boudreau <seanb@NetBSD.org> provided a security fix for virtual hosting
- Julian Coleman <jdc@coris.org.uk> provided an IPv6 bugfix
- Chuck Cranor <chuck@research.att.com> provided cgi-bin support fixes, and more
- Alistair G. Crooks <agc@NetBSD.org> cleaned up many internal interfaces, made `bozohttpd` linkable as a library and provided the Lua binding
- DEGROOTE Arnaud <degroote@NetBSD.org> provided a fix for daemon mode
- Andrew Doran <ad@NetBSD.org> provided directory indexing support
- Roland Dowdeswell <elric@NetBSD.org> added support for serving gzipped files and better SSL handling
- Per Ekman <pek@pdc.kth.se> provided a fix for a minor (non-security) buffer overflow condition
- <emily@ingalls.rocks> provided fixes for some bad request parsing
- Jun-ichiro itojun Hagino, KAME <itojun@iijlab.net> provided initial IPv6 support
- Martin Husemann <martin@NetBSD.org> provided .bzabsredirect and .bzredir support, fixed various redirection issues and more
- Arto Huusko <arto.huusko@pp2.inet.fi> provided fixes cgi-bin
- Roland Illig <roland.illig@gmx.de> provided some off-by-one fixes
- Zak Johnson <zakj@nox.cx> provided cgi-bin enhancements
- Nicolas Jombart <ecu@ipv42.net> provided fixes for HTTP basic authorization support
- Antti Kantee <pooka@NetBSD.org> provided fixes for HTTP basic authorization support
- Thomas Klausner <wiz@NetBSD.org> provided many fixes and enhancements for the man page
- Mateusz Kocielski <shm@NetBSD.org> fixed memory leaks, various issues with userdir support, information disclosure issues, added support for using CGI handlers with directory indexing, found several security issues and provided various other fixes
- Arnaud Lacombe <alc@NetBSD.org> provided some clean up for memory leaks
- Johnny Lam <jlam@NetBSD.org> provided man page fixes
- Dennis Lindroos <denafcm@gmail.com> provided a cgi-bin fix
- Jared McNeill <jmcneill@NetBSD.org> added support for readme in directory indexing
- Julio Merino <jmmv@NetBSD.org> Added the `-P` option (pidfile support) and provided some man page fixes
- Luke Mewburn <lukem@NetBSD.org> provided many various fixes, including cgi-bin fixes and enhancements, HTTP basic authorization support and much code clean up
- Rajeev V. Pillai <rajeev_v_pillai@yahoo.com> provided several fixes for virtual hosting and directory indexing and fixes for CGI
- Jeremy C. Reed <reed@NetBSD.org> provided several clean up fixes, and man page updates
- Scott Reynolds <scottr@NetBSD.org> provided various fixes
- Tyler Retzlaff <rtr@eterna.com.au> provided SSL support, cgi-bin fixes and much other random other stuff
- rudolf <netbsd@eq.cz> provided minor compile fixes and a CGI content map fix
- Steve Rumble <rumble@ephemeral.org> provided the `-V` option
- Jukka Ruohonen <jruoho@NetBSD.org> provided support for blocklistd(8)
- Thor Lancelot Simon <tls@NetBSD.org> enhanced cgi-bin support
- Joerg Sonnenberger <joerg@NetBSD.org> implemented If-Modified-Since support
- ISIHARA Takanori <ishit@oak.dti.ne.jp> provided a man page fix
- Holger Weiss <holger@CIS.FU-Berlin.DE> provided http authorization fixes
- <xs@kittenz.org> provided chroot and change-to-user support, and other various fixes

- S.P.Zeidler <spz@NetBSD.org> fixed several SSL shutdown issues
- Coyote Point provided various CGI fixes

There are probably others I have forgotten (let me know if you care)

Please send all updates to `bozohttpd` to <mrg@eterna.com.au> for inclusion in future releases.

# BUGS

`bozohttpd` does not handle HTTP/1.1 chunked input from the client yet.

February 27, 2021 | NetBSD 9.3