Webserv

firsts things first, must install php-cgi at least php-cgi

linux

• sudo apt install php-cgi

macos

• idk, try with brew bro.

In order to make python and ruby cgi works, you must make files executable.

Documentation

Build a simple http server from scratch (C)

RFC 7230 (message syntax and routing)

RFC 7231 (semantics and content)

RFC 7232 (conditional requests)

RFC 7233 (range requests)

RFC 7234 (catching)

RFC 7235 (authentication)

The Common Gateway Interface (CGI) Version 1.1

To do list / check list from subject:

General

• The C++ standard must be C++ 98. Your project must compile with it.
• No external library, no Boost, etc...
• It must be non-blocking and use only 1 poll (or equivalent) for all the IO between the client and the server (listens includes).
• poll (or equivalent) should check read and write at the same time.
• Your server should never block and the client should be bounce properly if necessary.
• You should never do a read operation or a write operation without going through poll (or equivalent).
• Checking the value of errno is strictly forbidden after a read or a write operation.
• A request to your server should never hang forever.
• You server should have default error pages if none are provided.
• Your program should not leak and should never crash, (even when out of memory if all the initialization is done)
• You can’t use fork for something else than CGI (like php or python etc...)
• You can’t execve another webserver...
• Your program should have a config file in argument or use a default path.
• You don’t need to use poll (or equivalent) before reading your config file.
• You should be able to serve a fully static website.
• Client should be able to upload files.
• Your HTTP response status codes must be accurate.
• You need at least GET, POST, and DELETE methods.
• Stress tests your server it must stay available at all cost.

Config file should be able to :

• choose the port and host of each "server"
• setup the server_names or not
• The first server for a host:port will be the default for this host:port (meaning it will answer to all request that doesn’t belong to an other server)
• setup default error pages
• limit client body size
• setup routes with one or multiple of the following rules/configuration (routes wont be using regexp):
  • define a list of accepted HTTP Methods for the route
  • define an HTTP redirection.
  • define a directory or a file from where the file should be search (for example if url /kapouet is rooted to /tmp/www, url /kapouet/pouic/toto/pouet is /tmp/www/pouic/toto/pouet)
  • turn on or off directory listing
  • default file to answer if the request is a directory
  • execute CGI based on certain file extension (for example .php)
    • You wonder what a CGI is ?
    • Because you won’t call the CGI directly use the full path as PATH_INFO
    • Just remembers that for chunked request, your server needs to unchunked it and the CGI will expect EOF as end of the body.
    • Same things for the output of the CGI. if no content_length is returned from the CGI, EOF will mean the end of the returned data.
    • Your program should call the cgi with the file requested as first argument
    • The cgi should be run in the correct directory for relativ path file access
    • Your server should work with one CGI (php-cgi, python...)
  • make the route able to accept uploaded files and configure where it should be saved
• You must provide some configuration files and default basic files to test/demonstrate every feature is working during eval

generated uml diagram webserv :

Refs :

• Design pattern helper
• Design pattern helper 2

http server + sockets, etc...

• Good server example, using builder and singleton pattern

  • design improved

• Socket programming tuto (java)

• Cours prog reseau c++ - Tcp - Premiers pas en tant que server

• Cours prog reseau c++ - Tcp - Un premier serveur

• Writing C++ HTTP server from scratch (1)-thread pool

• https://codereview.stackexchange.com/questions/217783/simple-http-server

• Let’s Build A Web Server (Python)

• Developing Flexible and High-performance Web Servers with Frameworks and Patterns

• http://manpagesfr.free.fr/man/man7/ip.7.html

• socket - Address family

• Basic socket design

• Advanced socket concepts - Non blocking I/O

• Async prog, blocking and non blocking I/O

Parsing http request

• Writing http parser

• Http Message Format

• Http Requests

• The anatomy of http request

• Design and Evaluation of HTTP Protocol Parsers

• Builder design pattern in modern c

• https://perishablepress.com/stop-using-unsafe-characters-in-urls/#unreserved-characters

• The normal procedure for parsing an HTTP message is to read the start-line into a structure, read each header field into a hash table by field name until the empty line, and then use the parsed data to determine if a message body is expected. If a message body has been indicated, then it is read as a stream until an amount of octets equal to the message body length is read or the connection is closed.

• Field value component (allowed char)

• https://stackoverflow.com/questions/47687379/what-characters-are-allowed-in-http-header-values

namespaces

• Namespace naming convention
• how to use namespace to separate interface from implementation
• The problems with Avoiding Smurf Naming classes with namespaces
• Multiple classes with the same name, but different namespaces?

Nginx doc

• nginx doc
• Creating NGINX Plus and NGINX Configuration Files
  • server block
• How nginx process request
• all nginx config directives

Sync fork

• Syncing a fork

config

• https://stackoverflow.com/questions/16041623/the-best-way-to-handle-config-in-large-c-project

• https://www.guru99.com/compiler-design-lexical-analysis.html#2

• https://stackoverflow.com/questions/14954721/what-is-the-difference-between-a-token-and-a-lexeme

• https://tlevesque.developpez.com/tutoriels/csharp/parser-texte-csharp-sprache/#Lno-III

• https://rosettacode.org/wiki/Compiler/lexical_analyzer

• https://visualstudiomagazine.com/articles/2014/06/01/compiler-basics-part-2.aspx

• https://www.nginx.com/wp-content/uploads/2018/12/NGINX-Conf-2018-slides_Hulegaard-config-analysis.pdf

• Scoped enum in c++98

• scanner class example

  • entire book (link above is missing explanations)

• std::variant an union...

• union and variant guideline

• c++98 - union restricted for complex type like string...and variant not in c++98...

• type punning using reinterpret cast undefined ?

• scanner - how to know if next-char is eof

• https://www.cs.colostate.edu/~mstrout/CS553Fall06/slides/lecture02a-scanparse.pdf

• for lexer parser example from father of c++

• How to parse http req - example lib poco

• Youtubev

• Youtube2 - LL(1)

• Youtube3 - LL(1) recursive decent parser stategy

• looking for a clear definition of what a tokenizer parser and lexers are

structure file interface, header...

• https://softwareengineering.stackexchange.com/questions/323738/how-can-i-effectively-use-one-file-per-class-in-c
• https://stackoverflow.com/questions/27102956/structuring-c-application-directory-and-folders
• https://www.fluentcpp.com/2017/09/22/make-pimpl-using-unique_ptr/

Google c++ style guide

• https://google.github.io/styleguide/cppguide.html

Sockets

• https://www.youtube.com/watch?v=YwHErWJIh6Y

FCGI

• http://www.chiark.greenend.org.uk/doc/libfcgi0ldbl/fastcgi-prog-guide/ch1intro.htm#9432

Http decision tree

• https://news.ycombinator.com/item?id=12067809
• https://github.com/for-GET/http-decision-diagram

Directory Traversal Attacks

• https://www.acunetix.com/websitesecurity/directory-traversal/

• https://www.joelonsoftware.com/2000/04/06/things-you-should-never-do-part-i/

valgrind

• https://valgrind.org/docs/manual/faq.html#faq.reports

filesystem

• https://en.cppreference.com/w/cpp/header/filesystem
• https://www.cppstories.com/2017/08/cpp17-details-filesystem/
• https://stackoverflow.com/questions/40899267/how-similar-are-boost-filesystem-and-the-c-standard-filesystem-library
• http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p1030r1.pdf
• http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2016/p0218r0.html

pimpl

• https://www.fluentcpp.com/2017/09/22/make-pimpl-using-unique_ptr/

• https://blog.spacepatroldelta.com/a?ID=01500-34f01d9e-2d48-4ea4-a26d-0a3deabfdb4b

Http connections

https://www.w3.org/Protocols/rfc2616/rfc2616-sec8.html

transfer encoding

• https://httpwg.org/specs/rfc7230.html#transfer.codings
• https://httpwg.org/specs/rfc7230.html#chunked.encoding
• https://httpwg.org/specs/rfc7230.html#decoding.chunked

other

• https://stackoverflow.com/questions/59261547/handle-ctrlc-in-client-server-socket-in-c-programing

cgi

• https://helpx.adobe.com/coldfusion/cfml-reference/reserved-words-and-variables/cgi-environment-cgi-scope-variables/cgi-server-variables.html
• http://www.faqs.org/rfcs/rfc3875.html
• https://www.php.net/manual/fr/reserved.variables.server.php

multipart

• https://stackoverflow.com/questions/913626/what-should-a-multipart-http-request-with-multiple-files-look-like
• https://www.w3.org/Protocols/rfc1341/7_2_Multipart.html
• https://developer.mozilla.org/fr/docs/Web/HTML/Element/Input/file
• https://www.w3.org/TR/html401/interact/forms.html#h-17.13.4.2

reactor and c10k problem

• https://dzone.com/articles/understanding-reactor-pattern-thread-based-and-eve
• http://www.kegel.com/c10k.html
• https://hila.sh/2019/12/28/reactor.html
• https://raw.githubusercontent.com/swn73/books/master/Packt.Nginx.HTTP.Server.3rd.Edition.pdf
• https://www.adamtornhill.com/Patterns%20in%20C%205,%20REACTOR.pdf

nginx

• https://raw.githubusercontent.com/swn73/books/master/Packt.Nginx.HTTP.Server.3rd.Edition.pdf

http header value ',' (list syntax) vs ';'

• https://stackoverflow.com/a/38406581/5374043
• https://github.com/bnoordhuis/mozilla-central/blob/master/netwerk/protocol/http/nsHttpHeaderArray.h#L185