Introduction

This project is a basic HTTP server written in C++98. The standards listed below (HTTP/CGI) are not completely implemented and were rather seen as a guideline to implement a usable server than a "to be followed requirement".

Functionality	Description	External info
HTTP	HTTP/1.1	RFC 2616 / RFC 9110 / RFC 9112
CGI	CGI/1.1 (Tested with php-cgi, using wordpress, and python cgi)	RFC 3875
Implemented methods	GET / HEAD / OPTIONS / POST / PUT / DELETE	RFC 2616 section 5.1.1
Basic cookie support	Tested with wordpress	RFC 2109
Argument flags	To description	-
Configuration file	To description	-

Table of Contents

• Linux installation
  • Requirements
  • Compilation
• Usage
  • Flags
• Configuration
  • Contexts
  • Directives
  • Example

Linux installation

Requirements

Docker or

apt install make

apt install clang

Compilation

Native

make [performance|debug|fsanitize]

Docker

This will create a mariadb docker container for the database another container which will setup wordpress, compile webserv execute it. To populate the container env credentials you can make a copy of the .env-example file and rename it to .env, make sure to change the default values according to your needs.

make -C docker up

Usage

./webserv [configuration_file] [ [-i|-h|-v|-c|-t] | [-o|-l|-a|-e ARGUMENT] ...]

Default configuration file: /etc/webserv/webserv.conf

Flags

A flag overwrites the default setting as well as the ones that are configured in the config file.

Flag	Description	Allowed values
i	Show info block when starting the server	NONE
h	Show help message and exit	NONE
v	Show version of webserv and exit	NONE
c	Show parsed config file structure and exit	NONE
t	Check if the config file syntax is valid and exit	NONE
o	Controls log_to_terminal	on/off
l	Controls log_level	0 / 1 / 2 / 3 / 4 for error / warning / info / debug / verbose
a	Controls access_log	PATH
e	Controls error_log	PATH

Flags can be utilized to configure an option directly from the start of the program instead of only after the configuration has been read and parsed.

Example:

./webserv [configuration_file] -s on -l 2 -a PATH

You can look at the parsing debug output by setting the flag o to on and the flag l to 3 or higher, this will override the default setting before the config has been read, parsed and applied. If you also want to write the parsing log messages to a file the flag a needs to be set to the PATH you want the log file to be. Those steps are necessary because even if you specify all the previous flag settings in the config file they will only be applied after having successfully loaded your config settings, which will, of course, happen after the config file has been parsed.

Configuration

The configuration file is used to define the configuration of the webserver. It is composed of directives. A directive is composed of a name arguments and a value. The value can be a string or a block. A block is a list of directives. The file webserv.conf demonstrates the default configuration of the webserv executable.

Config type	Options
Configuration file context	http / location / server
Configuration file directives	access_log / alias / allow / autoindex / cgi / cgi_timeout / client_timeout / error_log / error_page / include / index / listen / log_level / log_to_terminal / max_client_body_size / redirect / root / server_name / type

Contexts

Http

http {
  include PATH;

  types {
    [directives]
  }

  cgi_timeout NUMBER;
  client_timeout NUMBER;

  access_log PATH;
  error_log PATH;
  log_to_terminal [on|off];
  log_level LEVEL;

  server {
    [directives]
  }
}

Root context. It contains the global configuration of the webserver.
Allowed tokens: access_log / cgi_timeout / client_timeout/ error_log / include / log_level / log_to_terminal / server / types

Types

types {
  type MIME_TYPE EXTENSION [EXTENSION ...];
}

Types context. It contains the mime types of the server. The file mime.types provides an extensive default configuration for this context.
Allowed tokens: type

Server

server {
  listen HOST:PORT;
  server_name NAME [NAME ...];
  root PATH;
  index FILE [FILE ...];

  autoindex [on|off];
  max_client_body_size SIZE[k|m];
  allow METHOD [METHOD ...];
  error_page CODE PATH;
  cgi EXTENSION PATH;

  location PATH {
    [directives]
  }
}

Virtual server context. It contains the configuration of a virtual server.
Allowed tokens: allow / autoindex / cgi / error_page / index / listen / location / max_client_body_size / root / server_name

Location

location PATH {
  alias PATH;
  root PATH;
  index FILE [FILE ...];
  
  allow METHOD [METHOD ...];
  autoindex [on|off];
  redirect URL;
  max_client_body_size SIZE;
  cgi EXTENSTION PATH;
}

Location context for PATH. It contains the configuration of a location.
Allowed tokens: alias / allow / autoindex / cgi / index / max_client_body_size / redirect / root

Directives

access_log

access_log PATH;

Sets the path of the access log file.
Default: /var/log/webserv/access.log
Allowed in: Http

alias

alias PATH;

Set an alias path. Example request for alias PATH: GET /LOCATION_CONTEXT_PATH/file -> ROOT/PATH/file
Allowed in: Location

allow

allow METHOD [METHOD ...];

Sets the allowed methods for a context.
Default: GET / HEAD / OPTIONS
Allowed in: Http / Location

autoindex

autoindex [on|off];

Enables or disables the directory listing for a context
Default: off
Allowed in: Http / Location

cgi

cgi EXTENSTION PATH;

Sets the cgi EXECUTABLE to path for EXTENSION.
Allowed in: Location / Server

cgi_timeout

cgi_timeout NUMBER;

Sets the cgi timeout in milliseconds.
Default: 30000
Allowed in: Http

client_timout

client_timout NUMBER;

Sets the client timeout in milliseconds.
Default: 30000
Allowed in: Http

error_log

error_log PATH;

Sets the path of the error log file.
Default: /var/log/webserv/error.log
Allowed in: Http

error_page

error_page CODE PATH;

Sets a custom error page for the given status code.
Allowed in: Server

include

include PATH;

Include other configuration files. Supports * wildcard character Allowed in: Cgi / Http / Location / Server

index

index FILE [FILE ...];

Sets the index files for a context
Allowed in: Location / Server

listen

listen HOST:PORT;

Sets the host and port of the server.
Allowed in: Server

log_level

log_level LEVEL;

Set the log level. Allowed log levels are debug, info, warning, error and verbose.
Default: info
Allowed in: Http

log_to_terminal

log_to_terminal [on|off];

Sets whether logs should also be displayed on the terminal.
Default: off
Allowed in: Http

max_client_body_size

max_client_body_size SIZE[k|m];

Sets the maximum body size for a client request message. 1k is 1024 bytes, 1m is 1024k.
Default: 1m
Allowed in: Location / Server

redirect

redirect URL;

Redirects the request of the context to the given url.
Allowed in: Location / Server

root

root PATH;

Sets the root path for a context.
Allowed in: Location / Server

server_name

server_name NAME [NAME ...];

Sets the server names.
Allowed in: Server

type

type MIME_TYPE EXTENSION [EXTENSION ...];

Set the mime type for the given extensions.
Allowed in: Types

Example

# File -> /etc/webserv/mime.types
types {
  type text/html html htm;
  type text/css css;
  type text/javascript js;
  type image/jpeg jpeg jpg;
  type image/png png;
  type image/svg+xml svg;
  type image/gif gif;
}

# File -> /etc/webserv/webserv.conf
http {
  include /etc/webserv/mime.types;

  cgi_timeout 30000;
  client_timeout 30000;

  log_to_terminal off;
  log_level info;
  access_log /var/log/webserv/access.log;
  error_log /var/log/webserv/error.log;

  include /etc/webserv/sites-enabled/*;
}

# File -> /etc/webserv/sites-enabled/server.conf
server {
  listen 8080;
  root /var/www/html;
  index index.html index.htm;
  autoindex on;
  max_client_body_size 1m;
  allow GET HEAD OPTIONS;
  error_page 404 /404.html;
  cgi php /usr/bin/php-cgi;

  location /example {
    alias /www; # Request: GET /example/file -> ROOT/www/file
    index example.html;
    allow GET HEAD OPTIONS PUT DELETE;
    autoindex off;
  }
  location /redirect {
    redirect https://www.duckduckgo.com;
  }
}

./webserv [-i]