nghttp2 - HTTP/2 C Library
This is an implementation of the Hypertext Transfer Protocol version 2
in C.
The framing layer of HTTP/2 is implemented as a reusable C library.
On top of that, we have implemented an HTTP/2 client, server and
proxy. We have also developed load test and benchmarking tools for
HTTP/2.
An HPACK encoder and decoder are available as a public API.
An experimental high level C++ library is also available.
We have Python bindings of this library, but we do not have full
code coverage yet.
Development Status
We have implemented RFC 7540 <https://tools.ietf.org/html/rfc7540>_
HTTP/2 and RFC 7541 <https://tools.ietf.org/html/rfc7541>_ HPACK -
Header Compression for HTTP/2
The nghttp2 code base was forked from the spdylay
(https://github.com/tatsuhiro-t/spdylay) project.
Public Test Server
The following endpoints are available to try out our nghttp2
implementation.
-
https://nghttp2.org/ (TLS + ALPN/NPN)
This endpoint supports h2, h2-16, h2-14, and
http/1.1 via ALPN/NPN and requires TLSv1.2 for HTTP/2
connection.
-
http://nghttp2.org/ (HTTP Upgrade and HTTP/2 Direct)
h2c and http/1.1.
Requirements
The following package is required to build the libnghttp2 library:
To build and run the unit test programs, the following package is
required:
To build the documentation, you need to install:
If you need libnghttp2 (C library) only, then the above packages are
all you need. Use --enable-lib-only to ensure that only
libnghttp2 is built. This avoids potential build error related to
building bundled applications.
To build and run the application programs (nghttp, nghttpd,
nghttpx and h2load) in the src directory, the following packages
are required:
- OpenSSL >= 1.0.1
- libev >= 4.11
- zlib >= 1.2.3
- libc-ares >= 1.7.5
ALPN support requires OpenSSL >= 1.0.2 (released 22 January 2015).
LibreSSL >= 2.2.0 can be used instead of OpenSSL, but OpenSSL has more
features than LibreSSL at the time of this writing.
To enable -a option (getting linked assets from the downloaded
resource) in nghttp, the following package is required:
To enable systemd support in nghttpx, the following package is
required:
The HPACK tools require the following package:
To build sources under the examples directory, libevent is required:
- libevent-openssl >= 2.0.8
To mitigate heap fragmentation in long running server programs
(nghttpd and nghttpx), jemalloc is recommended:
libnghttp2_asio C++ library requires the following packages:
- libboost-dev >= 1.54.0
- libboost-thread-dev >= 1.54.0
The Python bindings require the following packages:
- cython >= 0.19
- python >= 2.7
- python-setuptools
If you are using Ubuntu 16.04 LTS (Xenial Xerus) or Debian 8 (jessie)
and above, run the following to install the required packages:
.. code-block:: text
sudo apt-get install g++ make binutils autoconf automake autotools-dev libtool pkg-config \
zlib1g-dev libcunit1-dev libssl-dev libxml2-dev libev-dev libevent-dev libjansson-dev \
libc-ares-dev libjemalloc-dev libsystemd-dev \
cython python3-dev python-setuptools
To enable mruby support for nghttpx, mruby <https://github.com/mruby/mruby>_ is required. We need to build
mruby with C++ ABI explicitly turned on, and probably need other
mrgems, mruby is manged by git submodule under third-party/mruby
directory. Currently, mruby support for nghttpx is disabled by
default. To enable mruby support, use --with-mruby configure
option. Note that at the time of this writing, libmruby-dev and mruby
packages in Debian/Ubuntu are not usable for nghttp2, since they do
not enable C++ ABI. To build mruby, the following packages are
required:
nghttpx supports neverbleed <https://github.com/h2o/neverbleed>_,
privilege separation engine for OpenSSL / LibreSSL. In short, it
minimizes the risk of private key leakage when serious bug like
Heartbleed is exploited. The neverbleed is disabled by default. To
enable it, use --with-neverbleed configure option.
Compiling libnghttp2 C source code requires a C99 compiler. gcc 4.8
is known to be adequate. In order to compile the C++ source code, gcc
= 6.0 or clang >= 6.0 is required. C++ source code requires C++14
language features.
.. note::
To enable mruby support in nghttpx, and use --with-mruby
configure option.
.. note::
Mac OS X users may need the --disable-threads configure option to
disable multi-threading in nghttpd, nghttpx and h2load to prevent
them from crashing. A patch is welcome to make multi threading work
on Mac OS X platform.
.. note::
To compile the associated applications (nghttp, nghttpd, nghttpx
and h2load), you must use the --enable-app configure option and
ensure that the specified requirements above are met. Normally,
configure script checks required dependencies to build these
applications, and enable --enable-app automatically, so you
don't have to use it explicitly. But if you found that
applications were not built, then using --enable-app may find
that cause, such as the missing dependency.
.. note::
In order to detect third party libraries, pkg-config is used
(however we don't use pkg-config for some libraries (e.g., libev)).
By default, pkg-config searches *.pc file in the standard
locations (e.g., /usr/lib/pkgconfig). If it is necessary to use
*.pc file in the custom location, specify paths to
PKG_CONFIG_PATH environment variable, and pass it to configure
script, like so:
.. code-block:: text
$ ./configure PKG_CONFIG_PATH=/path/to/pkgconfig
For pkg-config managed libraries, *_CFLAG and *_LIBS
environment variables are defined (e.g., OPENSSL_CFLAGS,
OPENSSL_LIBS). Specifying non-empty string to these variables
completely overrides pkg-config. In other words, if they are
specified, pkg-config is not used for detection, and user is
responsible to specify the correct values to these variables. For
complete list of these variables, run ./configure -h.
Building nghttp2 from release tar archive
The nghttp2 project regularly releases tar archives which includes
nghttp2 source code, and generated build files. They can be
downloaded from Releases <https://github.com/nghttp2/nghttp2/releases>_ page.
Building nghttp2 from git requires autotools development packages.
Building from tar archives does not require them, and thus it is much
easier. The usual build step is as follows:
.. code-block:: text
$ tar xf nghttp2-X.Y.Z.tar.bz2
$ cd nghttp2-X.Y.Z
$ ./configure
$ make
Building from git
Building from git is easy, but please be sure that at least autoconf 2.68 is
used:
.. code-block:: text
$ git submodule update --init
$ autoreconf -i
$ automake
$ autoconf
$ ./configure
$ make
Notes for building on Windows (MSVC)
The easiest way to build native Windows nghttp2 dll is use cmake <https://cmake.org/>. The free version of Visual C++ Build Tools <http://landinghub.visualstudio.com/visual-cpp-build-tools> works
fine.
- Install cmake for windows
- Open "Visual C++ ... Native Build Tool Command Prompt", and inside
nghttp2 directly, run cmake.
- Then run
cmake --build to build library.
- nghttp2.dll, nghttp2.lib, nghttp2.exp are placed under lib directory.
Note that the above steps most likely produce nghttp2 library only.
No bundled applications are compiled.
Notes for building on Windows (Mingw/Cygwin)
Under Mingw environment, you can only compile the library, it's
libnghttp2-X.dll and libnghttp2.a.
If you want to compile the applications(h2load, nghttp,
nghttpx, nghttpd), you need to use the Cygwin environment.
Under Cygwin environment, to compile the applications you need to
compile and install the libev first.
Secondly, you need to undefine the macro __STRICT_ANSI__, if you
not, the functions fdopen, fileno and strptime will not
available.
the sample command like this:
.. code-block:: text
$ export CFLAGS="-U__STRICT_ANSI__ -I$libev_PREFIX/include -L$libev_PREFIX/lib"
$ export CXXFLAGS=$CFLAGS
$ ./configure
$ make
If you want to compile the applications under examples/, you need
to remove or rename the event.h from libev's installation, because
it conflicts with libevent's installation.
Notes for installation on Linux systems
After installing nghttp2 tool suite with make install one might experience a similar error:
.. code-block:: text
nghttpx: error while loading shared libraries: libnghttp2.so.14: cannot open shared object file: No such file or directory
This means that the tool is unable to locate the libnghttp2.so shared library.
To update the shared library cache run sudo ldconfig.
Building the documentation
.. note::
Documentation is still incomplete.
To build the documentation, run:
.. code-block:: text
$ make html
The documents will be generated under doc/manual/html/.
The generated documents will not be installed with make install.
The online documentation is available at
https://nghttp2.org/documentation/
Unit tests
Unit tests are done by simply running make check.
Integration tests
We have the integration tests for the nghttpx proxy server. The tests are
written in the Go programming language <http://golang.org/>_ and uses
its testing framework. We depend on the following libraries:
Go modules will download these dependencies automatically.
To run the tests, run the following command under
integration-tests directory:
.. code-block:: text
$ make it
Inside the tests, we use port 3009 to run the test subject server.
Migration from v0.7.15 or earlier
nghttp2 v1.0.0 introduced several backward incompatible changes. In
this section, we describe these changes and how to migrate to v1.0.0.
ALPN protocol ID is now h2 and h2c
++++++++++++++++++++++++++++++++++++++++++
Previously we announced h2-14 and h2c-14. v1.0.0 implements
final protocol version, and we changed ALPN ID to h2 and h2c.
The macros NGHTTP2_PROTO_VERSION_ID,
NGHTTP2_PROTO_VERSION_ID_LEN,
NGHTTP2_CLEARTEXT_PROTO_VERSION_ID, and
NGHTTP2_CLEARTEXT_PROTO_VERSION_ID_LEN have been updated to
reflect this change.
Basically, existing applications do not have to do anything, just
recompiling is enough for this change.
Use word "client magic" where we use "client connection preface"
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
We use "client connection preface" to mean first 24 bytes of client
connection preface. This is technically not correct, since client
connection preface is composed of 24 bytes client magic byte string
followed by SETTINGS frame. For clarification, we call "client magic"
for this 24 bytes byte string and updated API.
NGHTTP2_CLIENT_CONNECTION_PREFACE was replaced with
NGHTTP2_CLIENT_MAGIC.NGHTTP2_CLIENT_CONNECTION_PREFACE_LEN was replaced with
NGHTTP2_CLIENT_MAGIC_LEN.NGHTTP2_BAD_PREFACE was renamed as NGHTTP2_BAD_CLIENT_MAGIC
The already deprecated NGHTTP2_CLIENT_CONNECTION_HEADER and
NGHTTP2_CLIENT_CONNECTION_HEADER_LEN were removed.
If application uses these macros, just replace old ones with new ones.
Since v1.0.0, client magic is sent by library (see next subsection),
so client application may just remove these macro use.
Client magic is sent by library
+++++++++++++++++++++++++++++++
Previously nghttp2 library did not send client magic, which is first
24 bytes byte string of client connection preface, and client
applications have to send it by themselves. Since v1.0.0, client
magic is sent by library via first call of nghttp2_session_send()
or nghttp2_session_mem_send().
The client applications which send client magic must remove the
relevant code.
Remove HTTP Alternative Services (Alt-Svc) related code
+++++++++++++++++++++++++++++++++++++++++++++++++++++++
Alt-Svc specification is not finalized yet. To make our API stable,
we have decided to remove all Alt-Svc related API from nghttp2.
NGHTTP2_EXT_ALTSVC was removed.nghttp2_ext_altsvc was removed.
We have already removed the functionality of Alt-Svc in v0.7 series
and they have been essentially noop. The application using these
macro and struct, remove those lines.
Use nghttp2_error in nghttp2_on_invalid_frame_recv_callback
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Previously nghttp2_on_invalid_frame_recv_cb_called took the
error_code, defined in nghttp2_error_code, as parameter. But
they are not detailed enough to debug. Therefore, we decided to use
more detailed nghttp2_error values instead.
The application using this callback should update the callback
signature. If it treats error_code as HTTP/2 error code, update
the code so that it is treated as nghttp2_error.
Receive client magic by default
+++++++++++++++++++++++++++++++
Previously nghttp2 did not process client magic (24 bytes byte
string). To make it deal with it, we had to use
nghttp2_option_set_recv_client_preface(). Since v1.0.0, nghttp2
processes client magic by default and
nghttp2_option_set_recv_client_preface() was removed.
Some application may want to disable this behaviour, so we added
nghttp2_option_set_no_recv_client_magic() to achieve this.
The application using nghttp2_option_set_recv_client_preface()
with nonzero value, just remove it.
The application using nghttp2_option_set_recv_client_preface()
with zero value or not using it must use
nghttp2_option_set_no_recv_client_magic() with nonzero value.
Client, Server and Proxy programs
The src directory contains the HTTP/2 client, server and proxy programs.
nghttp - client
+++++++++++++++
nghttp is a HTTP/2 client. It can connect to the HTTP/2 server
with prior knowledge, HTTP Upgrade and NPN/ALPN TLS extension.
It has verbose output mode for framing information. Here is sample
output from nghttp client:
.. code-block:: text
$ nghttp -nv https://nghttp2.org
[ 0.190] Connected
The negotiated protocol: h2
[ 0.212] recv SETTINGS frame <length=12, flags=0x00, stream_id=0>
(niv=2)
[SETTINGS_MAX_CONCURRENT_STREAMS(0x03):100]
[SETTINGS_INITIAL_WINDOW_SIZE(0x04):65535]
[ 0.212] send SETTINGS frame <length=12, flags=0x00, stream_id=0>
(niv=2)
[SETTINGS_MAX_CONCURRENT_STREAMS(0x03):100]
[SETTINGS_INITIAL_WINDOW_SIZE(0x04):65535]
[ 0.212] send SETTINGS frame <length=0, flags=0x01, stream_id=0>
; ACK
(niv=0)
[ 0.212] send PRIORITY frame <length=5, flags=0x00, stream_id=3>
(dep_stream_id=0, weight=201, exclusive=0)
[ 0.212] send PRIORITY frame <length=5, flags=0x00, stream_id=5>
(dep_stream_id=0, weight=101, exclusive=0)
[ 0.212] send PRIORITY frame <length=5, flags=0x00, stream_id=7>
(dep_stream_id=0, weight=1, exclusive=0)
[ 0.212] send PRIORITY frame <length=5, flags=0x00, stream_id=9>
(dep_stream_id=7, weight=1, exclusive=0)
[ 0.212] send PRIORITY frame <length=5, flags=0x00, stream_id=11>
(dep_stream_id=3, weight=1, exclusive=0)
[ 0.212] send HEADERS frame <length=39, flags=0x25, stream_id=13>
; END_STREAM, END_HEADERS, PRIORITY
(padlen=0, dep_stream_id=11, weight=16, exclusive=0)
; Open new stream
:method: GET
:path: /
:scheme: https
:authority: nghttp2.org
accept: */*
accept-encoding: gzip, deflate
user-agent: nghttp2/1.0.1-DEV
[ 0.221] recv SETTINGS frame <length=0, flags=0x01, stream_id=0>
; ACK
(niv=0)
[ 0.221] recv (stream_id=13) :method: GET
[ 0.221] recv (stream_id=13) :scheme: https
[ 0.221] recv (stream_id=13) :path: /stylesheets/screen.css
[ 0.221] recv (stream_id=13) :authority: nghttp2.org
[ 0.221] recv (stream_id=13) accept-encoding: gzip, deflate
[ 0.222] recv (stream_id=13) user-agent: nghttp2/1.0.1-DEV
[ 0.222] recv PUSH_PROMISE frame <length=50, flags=0x04, stream_id=13>
; END_HEADERS
(padlen=0, promised_stream_id=2)
[ 0.222] recv (stream_id=13) :status: 200
[ 0.222] recv (stream_id=13) date: Thu, 21 May 2015 16:38:14 GMT
[ 0.222] recv (stream_id=13) content-type: text/html
[ 0.222] recv (stream_id=13) last-modified: Fri, 15 May 2015 15:38:06 GMT
[ 0.222] recv (stream_id=13) etag: W/"555612de-19f6"
[ 0.222] recv (stream_id=13) link: </stylesheets/screen.css>; rel=preload; as=stylesheet
[ 0.222] recv (stream_id=13) content-encoding: gzip
[ 0.222] recv (stream_id=13) server: nghttpx nghttp2/1.0.1-DEV
[ 0.222] recv (stream_id=13) via: 1.1 nghttpx
[ 0.222] recv (stream_id=13) strict-transport-security: max-age=31536000
[ 0.222] recv HEADERS frame <length=166, flags=0x04, stream_id=13>
; END_HEADERS
(padlen=0)
; First response header
[ 0.222] recv DATA frame <length=2601, flags=0x01, stream_id=13>
; END_STREAM
[ 0.222] recv (stream_id=2) :status: 200
[ 0.222] recv (stream_id=2) date: Thu, 21 May 2015 16:38:14 GMT
[ 0.222] recv (stream_id=2) content-type: text/css
[ 0.222] recv (stream_id=2) last-modified: Fri, 15 May 2015 15:38:06 GMT
[ 0.222] recv (stream_id=2) etag: W/"555612de-9845"
[ 0.222] recv (stream_id=2) content-encoding: gzip
[ 0.222] recv (stream_id=2) server: nghttpx nghttp2/1.0.1-DEV
[ 0.222] recv (stream_id=2) via: 1.1 nghttpx
[ 0.222] recv (stream_id=2) strict-transport-security: max-age=31536000
[ 0.222] recv HEADERS frame <length=32, flags=0x04, stream_id=2>
; END_HEADERS
(padlen=0)
; First push response header
[ 0.228] recv DATA frame <length=8715, flags=0x01, stream_id=2>
; END_STREAM
[ 0.228] send GOAWAY frame <length=8, flags=0x00, stream_id=0>
(last_stream_id=2, error_code=NO_ERROR(0x00), opaque_data(0)=[])
The HTTP Upgrade is performed like so:
.. code-block:: text
$ nghttp -nvu http://nghttp2.org
[ 0.011] Connected
[ 0.011] HTTP Upgrade request
GET / HTTP/1.1
Host: nghttp2.org
Connection: Upgrade, HTTP2-Settings
Upgrade: h2c
HTTP2-Settings: AAMAAABkAAQAAP__
Accept: */*
User-Agent: nghttp2/1.0.1-DEV
[ 0.018] HTTP Upgrade response
HTTP/1.1 101 Switching Protocols
Connection: Upgrade
Upgrade: h2c
[ 0.018] HTTP Upgrade success
[ 0.018] recv SETTINGS frame <length=12, flags=0x00, stream_id=0>
(niv=2)
[SETTINGS_MAX_CONCURRENT_STREAMS(0x03):100]
[SETTINGS_INITIAL_WINDOW_SIZE(0x04):65535]
[ 0.018] send SETTINGS frame <length=12, flags=0x00, stream_id=0>
(niv=2)
[SETTINGS_MAX_CONCURRENT_STREAMS(0x03):100]
[SETTINGS_INITIAL_WINDOW_SIZE(0x04):65535]
[ 0.018] send SETTINGS frame <length=0, flags=0x01, stream_id=0>
; ACK
(niv=0)
[ 0.018] send PRIORITY frame <length=5, flags=0x00, stream_id=3>
(dep_stream_id=0, weight=201, exclusive=0)
[ 0.018] send PRIORITY frame <length=5, flags=0x00, stream_id=5>
(dep_stream_id=0, weight=101, exclusive=0)
[ 0.018] send PRIORITY frame <length=5, flags=0x00, stream_id=7>
(dep_stream_id=0, weight=1, exclusive=0)
[ 0.018] send PRIORITY frame <length=5, flags=0x00, stream_id=9>
(dep_stream_id=7, weight=1, exclusive=0)
[ 0.018] send PRIORITY frame <length=5, flags=0x00, stream_id=11>
(dep_stream_id=3, weight=1, exclusive=0)
[ 0.018] send PRIORITY frame <length=5, flags=0x00, stream_id=1>
(dep_stream_id=11, weight=16, exclusive=0)
[ 0.019] recv (stream_id=1) :method: GET
[ 0.019] recv (stream_id=1) :scheme: http
[ 0.019] recv (stream_id=1) :path: /stylesheets/screen.css
[ 0.019] recv (stream_id=1) host: nghttp2.org
[ 0.019] recv (stream_id=1) user-agent: nghttp2/1.0.1-DEV
[ 0.019] recv PUSH_PROMISE frame <length=49, flags=0x04, stream_id=1>
; END_HEADERS
(padlen=0, promised_stream_id=2)
[ 0.019] recv (stream_id=1) :status: 200
[ 0.019] recv (stream_id=1) date: Thu, 21 May 2015 16:39:16 GMT
[ 0.019] recv (stream_id=1) content-type: text/html
[ 0.019] recv (stream_id=1) content-length: 6646
[ 0.019] recv (stream_id=1) last-modified: Fri, 15 May 2015 15:38:06 GMT
[ 0.019] recv (stream_id=1) etag: "555612de-19f6"
[ 0.019] recv (stream_id=1) link: </stylesheets/screen.css>; rel=preload; as=stylesheet
[ 0.019] recv (stream_id=1) accept-ranges: bytes
[ 0.019] recv (stream_id=1) server: nghttpx nghttp2/1.0.1-DEV
[ 0.019] recv (stream_id=1) via: 1.1 nghttpx
[ 0.019] recv HEADERS frame <length=157, flags=0x04, stream_id=1>
; END_HEADERS
(padlen=0)
; First response header
[ 0.019] recv DATA frame <length=6646, flags=0x01, stream_id=1>
; END_STREAM
[ 0.019] recv (stream_id=2) :status: 200
[ 0.019] recv (stream_id=2) date: Thu, 21 May 2015 16:39:16 GMT
[ 0.019] recv (stream_id=2) content-type: text/css
[ 0.019] recv (stream_id=2) content-length: 38981
[ 0.019] recv (stream_id=2) last-modified: Fri, 15 May 2015 15:38:06 GMT
[ 0.019] recv (stream_id=2) etag: "555612de-9845"
[ 0.019] recv (stream_id=2) accept-ranges: bytes
[ 0.019] recv (stream_id=2) server: nghttpx nghttp2/1.0.1-DEV
[ 0.019] recv (stream_id=2) via: 1.1 nghttpx
[ 0.019] recv HEADERS frame <length=36, flags=0x04, stream_id=2>
; END_HEADERS
(padlen=0)
; First push response header
[ 0.026] recv DATA frame <length=16384, flags=0x00, stream_id=2>
[ 0.027] recv DATA frame <length=7952, flags=0x00, stream_id=2>
[ 0.027] send WINDOW_UPDATE frame <length=4, flags=0x00, stream_id=0>
(window_size_increment=33343)
[ 0.032] send WINDOW_UPDATE frame <length=4, flags=0x00, stream_id=2>
(window_size_increment=33707)
[ 0.032] recv DATA frame <length=14645, flags=0x01, stream_id=2>
; END_STREAM
[ 0.032] recv SETTINGS frame <length=0, flags=0x01, stream_id=0>
; ACK
(niv=0)
[ 0.032] send GOAWAY frame <length=8, flags=0x00, stream_id=0>
(last_stream_id=2, error_code=NO_ERROR(0x00), opaque_data(0)=[])
Using the -s option, nghttp prints out some timing information for
requests, sorted by completion time:
.. code-block:: text
$ nghttp -nas https://nghttp2.org/
***** Statistics *****
Request timing:
responseEnd: the time when last byte of response was received
relative to connectEnd
requestStart: the time just before first byte of request was sent
relative to connectEnd. If '*' is shown, this was
pushed by server.
process: responseEnd - requestStart
code: HTTP status code
size: number of bytes received as response body without
inflation.
URI: request URI
see http://www.w3.org/TR/resource-timing/#processing-model
sorted by 'complete'
id responseEnd requestStart process code size request path
13 +37.19ms +280us 36.91ms 200 2K /
2 +72.65ms * +36.38ms 36.26ms 200 8K /stylesheets/screen.css
17 +77.43ms +38.67ms 38.75ms 200 3K /javascripts/octopress.js
15 +78.12ms +38.66ms 39.46ms 200 3K /javascripts/modernizr-2.0.js
Using the -r option, nghttp writes more detailed timing data to
the given file in HAR format.
nghttpd - server
++++++++++++++++
nghttpd is a multi-threaded static web server.
By default, it uses SSL/TLS connection. Use --no-tls option to
disable it.
nghttpd only accepts HTTP/2 connections via NPN/ALPN or direct
HTTP/2 connections. No HTTP Upgrade is supported.
The -p option allows users to configure server push.
Just like nghttp, it has a verbose output mode for framing
information. Here is sample output from nghttpd:
.. code-block:: text
$ nghttpd --no-tls -v 8080
IPv4: listen 0.0.0.0:8080
IPv6: listen :::8080
[id=1] [ 1.521] send SETTINGS frame <length=6, flags=0x00, stream_id=0>
(niv=1)
[SETTINGS_MAX_CONCURRENT_STREAMS(0x03):100]
[id=1] [ 1.521] recv SETTINGS frame <length=12, flags=0x00, stream_id=0>
(niv=2)
[SETTINGS_MAX_CONCURRENT_STREAMS(0x03):100]
[SETTINGS_INITIAL_WINDOW_SIZE(0x04):65535]
[id=1] [ 1.521] recv SETTINGS frame <length=0, flags=0x01, stream_id=0>
; ACK
(niv=0)
[id=1] [ 1.521] recv PRIORITY frame <length=5, flags=0x00, stream_id=3>
(dep_stream_id=0, weight=201, exclusive=0)
[id=1] [ 1.521] recv PRIORITY frame <length=5, flags=0x00, stream_id=5>
(dep_stream_id=0, weight=101, exclusive=0)
[id=1] [ 1.521] recv PRIORITY frame <length=5, flags=0x00, stream_id=7>
(dep_stream_id=0, weight=1, exclusive=0)
[id=1] [ 1.521] recv PRIORITY frame <length=5, flags=0x00, stream_id=9>
(dep_stream_id=7, weight=1, exclusive=0)
[id=1] [ 1.521] recv PRIORITY frame <length=5, flags=0x00, stream_id=11>
(dep_stream_id=3, weight=1, exclusive=0)
[id=1] [ 1.521] recv (stream_id=13) :method: GET
[id=1] [ 1.521] recv (stream_id=13) :path: /
[id=1] [ 1.521] recv (stream_id=13) :scheme: http
[id=1] [ 1.521] recv (stream_id=13) :authority: localhost:8080
[id=1] [ 1.521] recv (stream_id=13) accept: */*
[id=1] [ 1.521] recv (stream_id=13) accept-encoding: gzip, deflate
[id=1] [ 1.521] recv (stream_id=13) user-agent: nghttp2/1.0.0-DEV
[id=1] [ 1.521] recv HEADERS frame <length=41, flags=0x25, stream_id=13>
; END_STREAM, END_HEADERS, PRIORITY
(padlen=0, dep_stream_id=11, weight=16, exclusive=0)
; Open new stream
[id=1] [ 1.521] send SETTINGS frame <length=0, flags=0x01, stream_id=0>
; ACK
(niv=0)
[id=1] [ 1.521] send HEADERS frame <length=86, flags=0x04, stream_id=13>
; END_HEADERS
(padlen=0)
; First response header
:status: 200
server: nghttpd nghttp2/1.0.0-DEV
content-length: 10
cache-control: max-age=3600
date: Fri, 15 May 2015 14:49:04 GMT
last-modified: Tue, 30 Sep 2014 12:40:52 GMT
[id=1] [ 1.522] send DATA frame <length=10, flags=0x01, stream_id=13>
; END_STREAM
[id=1] [ 1.522] stream_id=13 closed
[id=1] [ 1.522] recv GOAWAY frame <length=8, flags=0x00, stream_id=0>
(last_stream_id=0, error_code=NO_ERROR(0x00), opaque_data(0)=[])
[id=1] [ 1.522] closed
nghttpx - proxy
+++++++++++++++
nghttpx is a multi-threaded reverse proxy for HTTP/2, and
HTTP/1.1, and powers http://nghttp2.org and supports HTTP/2 server
push.
We reworked nghttpx command-line interface, and as a result, there
are several incompatibles from 1.8.0 or earlier. This is necessary to
extend its capability, and secure the further feature enhancements in
the future release. Please read Migration from nghttpx v1.8.0 or earlier <https://nghttp2.org/documentation/nghttpx-howto.html#migration-from-nghttpx-v1-8-0-or-earlier>_
to know how to migrate from earlier releases.
nghttpx implements important performance-oriented features <https://istlsfastyet.com/#server-performance>_ in TLS, such as
session IDs, session tickets (with automatic key rotation), OCSP
stapling, dynamic record sizing, ALPN/NPN, forward secrecy and HTTP/2.
nghttpx also offers the functionality to share session cache and
ticket keys among multiple nghttpx instances via memcached.
nghttpx has 2 operation modes:
================== ================ ================ =============
Mode option Frontend Backend Note
================== ================ ================ =============
default mode HTTP/2, HTTP/1.1 HTTP/1.1, HTTP/2 Reverse proxy
--http2-proxy HTTP/2, HTTP/1.1 HTTP/1.1, HTTP/2 Forward proxy
================== ================ ================ =============
The interesting mode at the moment is the default mode. It works like
a reverse proxy and listens for HTTP/2, and HTTP/1.1 and can be
deployed as a SSL/TLS terminator for existing web server.
In all modes, the frontend connections are encrypted by SSL/TLS by
default. To disable encryption, use the no-tls keyword in
--frontend option. If encryption is disabled, incoming HTTP/1.1
connections can be upgraded to HTTP/2 through HTTP Upgrade. On the
other hard, backend connections are not encrypted by default. To
encrypt backend connections, use tls keyword in --backend
option.
nghttpx supports a configuration file. See the --conf option and
sample configuration file nghttpx.conf.sample.
In the default mode, nghttpx works as reverse proxy to the backend
server:
.. code-block:: text
Client <-- (HTTP/2, HTTP/1.1) --> nghttpx <-- (HTTP/1.1, HTTP/2) --> Web Server
[reverse proxy]
With the --http2-proxy option, it works as forward proxy, and it
is so called secure HTTP/2 proxy:
.. code-block:: text
Client <-- (HTTP/2, HTTP/1.1) --> nghttpx <-- (HTTP/1.1) --> Proxy
[secure proxy] (e.g., Squid, ATS)
The Client in the above example needs to be configured to use
nghttpx as secure proxy.
At the time of this writing, both Chrome and Firefox support secure
HTTP/2 proxy. One way to configure Chrome to use a secure proxy is to
create a proxy.pac script like this:
.. code-block:: javascript
function FindProxyForURL(url, host) {
return "HTTPS SERVERADDR:PORT";
}
SERVERADDR and PORT is the hostname/address and port of the
machine nghttpx is running on. Please note that Chrome requires a valid
certificate for secure proxy.
Then run Chrome with the following arguments:
.. code-block:: text
$ google-chrome --proxy-pac-url=file:///path/to/proxy.pac --use-npn
The backend HTTP/2 connections can be tunneled through an HTTP proxy.
The proxy is specified using --backend-http-proxy-uri. The
following figure illustrates how nghttpx talks to the outside HTTP/2
proxy through an HTTP proxy:
.. code-block:: text
Client <-- (HTTP/2, HTTP/1.1) --> nghttpx <-- (HTTP/2) --
--===================---> HTTP/2 Proxy
(HTTP proxy tunnel) (e.g., nghttpx -s)
The h2load program is a benchmarking tool for HTTP/2. The UI of
h2load is heavily inspired by weighttp
(https://github.com/lighttpd/weighttp). The typical usage is as
follows:
.. code-block:: text
$ h2load -n100000 -c100 -m100 https://localhost:8443/
starting benchmark...
spawning thread #0: 100 concurrent clients, 100000 total requests
Protocol: TLSv1.2
Cipher: ECDHE-RSA-AES128-GCM-SHA256
Server Temp Key: ECDH P-256 256 bits
progress: 10% done
progress: 20% done
progress: 30% done
progress: 40% done
progress: 50% done
progress: 60% done
progress: 70% done
progress: 80% done
progress: 90% done
progress: 100% done
finished in 771.26ms, 129658 req/s, 4.71MB/s
requests: 100000 total, 100000 started, 100000 done, 100000 succeeded, 0 failed, 0 errored
status codes: 100000 2xx, 0 3xx, 0 4xx, 0 5xx
traffic: 3812300 bytes total, 1009900 bytes headers, 1000000 bytes data
min max mean sd +/- sd
time for request: 25.12ms 124.55ms 51.07ms 15.36ms 84.87%
time for connect: 208.94ms 254.67ms 241.38ms 7.95ms 63.00%
time to 1st byte: 209.11ms 254.80ms 241.51ms 7.94ms 63.00%
The above example issued total 100,000 requests, using 100 concurrent
clients (in other words, 100 HTTP/2 sessions), and a maximum of 100 streams
per client. With the -t option, h2load will use multiple native
threads to avoid saturating a single core on client side.
.. warning::
Don't use this tool against publicly available servers. That is
considered a DOS attack. Please only use it against your private
servers.
The src directory contains the HPACK tools. The deflatehd program is a
command-line header compression tool. The inflatehd program is a
command-line header decompression tool. Both tools read input from
stdin and write output to stdout. Errors are written to stderr.
They take JSON as input and output. We (mostly) use the same JSON data
format described at https://github.com/http2jp/hpack-test-case.
deflatehd - header compressor
+++++++++++++++++++++++++++++
The deflatehd program reads JSON data or HTTP/1-style header fields from
stdin and outputs compressed header block in JSON.
For the JSON input, the root JSON object must include a cases key.
Its value has to include the sequence of input header set. They share
the same compression context and are processed in the order they
appear. Each item in the sequence is a JSON object and it must
include a headers key. Its value is an array of JSON objects,
which includes exactly one name/value pair.
Example:
.. code-block:: json
{
"cases":
[
{
"headers": [
{ ":method": "GET" },
{ ":path": "/" }
]
},
{
"headers": [
{ ":method": "POST" },
{ ":path": "/" }
]
}
]
}
With the -t option, the program can accept more familiar HTTP/1 style
header field blocks. Each header set is delimited by an empty line:
Example:
.. code-block:: text
:method: GET
:scheme: https
:path: /
:method: POST
user-agent: nghttp2
The output is in JSON object. It should include a cases key and its
value is an array of JSON objects, which has at least the following keys:
seq
The index of header set in the input.
input_length
The sum of the length of the name/value pairs in the input.
output_length
The length of the compressed header block.
percentage_of_original_size
output_length / input_length * 100
wire
The compressed header block as a hex string.
headers
The input header set.
header_table_size
The header table size adjusted before deflating the header set.
Examples:
.. code-block:: json
{
"cases":
[
{
"seq": 0,
"input_length": 66,
"output_length": 20,
"percentage_of_original_size": 30.303030303030305,
"wire": "01881f3468e5891afcbf83868a3d856659c62e3f",
"headers": [
{
":authority": "example.org"
},
{
":method": "GET"
},
{
":path": "/"
},
{
":scheme": "https"
},
{
"user-agent": "nghttp2"
}
],
"header_table_size": 4096
}
,
{
"seq": 1,
"input_length": 74,
"output_length": 10,
"percentage_of_original_size": 13.513513513513514,
"wire": "88448504252dd5918485",
"headers": [
{
":authority": "example.org"
},
{
":method": "POST"
},
{
":path": "/account"
},
{
":scheme": "https"
},
{
"user-agent": "nghttp2"
}
],
"header_table_size": 4096
}
]
}
The output can be used as the input for inflatehd and
deflatehd.
With the -d option, the extra header_table key is added and its
associated value includes the state of dynamic header table after the
corresponding header set was processed. The value includes at least
the following keys:
entries
The entry in the header table. If referenced is true, it
is in the reference set. The size includes the overhead (32
bytes). The index corresponds to the index of header table.
The name is the header field name and the value is the
header field value.
size
The sum of the spaces entries occupied, this includes the
entry overhead.
max_size
The maximum header table size.
deflate_size
The sum of the spaces entries occupied within
max_deflate_size.
max_deflate_size
The maximum header table size the encoder uses. This can be smaller
than max_size. In this case, the encoder only uses up to first
max_deflate_size buffer. Since the header table size is still
max_size, the encoder has to keep track of entries outside the
max_deflate_size but inside the max_size and make sure
that they are no longer referenced.
Example:
.. code-block:: json
{
"cases":
[
{
"seq": 0,
"input_length": 66,
"output_length": 20,
"percentage_of_original_size": 30.303030303030305,
"wire": "01881f3468e5891afcbf83868a3d856659c62e3f",
"headers": [
{
":authority": "example.org"
},
{
":method": "GET"
},
{
":path": "/"
},
{
":scheme": "https"
},
{
"user-agent": "nghttp2"
}
],
"header_table_size": 4096,
"header_table": {
"entries": [
{
"index": 1,
"name": "user-agent",
"value": "nghttp2",
"referenced": true,
"size": 49
},
{
"index": 2,
"name": ":scheme",
"value": "https",
"referenced": true,
"size": 44
},
{
"index": 3,
"name": ":path",
"value": "/",
"referenced": true,
"size": 38
},
{
"index": 4,
"name": ":method",
"value": "GET",
"referenced": true,
"size": 42
},
{
"index": 5,
"name": ":authority",
"value": "example.org",
"referenced": true,
"size": 53
}
],
"size": 226,
"max_size": 4096,
"deflate_size": 226,
"max_deflate_size": 4096
}
}
,
{
"seq": 1,
"input_length": 74,
"output_length": 10,
"percentage_of_original_size": 13.513513513513514,
"wire": "88448504252dd5918485",
"headers": [
{
":authority": "example.org"
},
{
":method": "POST"
},
{
":path": "/account"
},
{
":scheme": "https"
},
{
"user-agent": "nghttp2"
}
],
"header_table_size": 4096,
"header_table": {
"entries": [
{
"index": 1,
"name": ":method",
"value": "POST",
"referenced": true,
"size": 43
},
{
"index": 2,
"name": "user-agent",
"value": "nghttp2",
"referenced": true,
"size": 49
},
{
"index": 3,
"name": ":scheme",
"value": "https",
"referenced": true,
"size": 44
},
{
"index": 4,
"name": ":path",
"value": "/",
"referenced": false,
"size": 38
},
{
"index": 5,
"name": ":method",
"value": "GET",
"referenced": false,
"size": 42
},
{
"index": 6,
"name": ":authority",
"value": "example.org",
"referenced": true,
"size": 53
}
],
"size": 269,
"max_size": 4096,
"deflate_size": 269,
"max_deflate_size": 4096
}
}
]
}
inflatehd - header decompressor
+++++++++++++++++++++++++++++++
The inflatehd program reads JSON data from stdin and outputs decompressed
name/value pairs in JSON.
The root JSON object must include the cases key. Its value has to
include the sequence of compressed header blocks. They share the same
compression context and are processed in the order they appear. Each
item in the sequence is a JSON object and it must have at least a
wire key. Its value is a compressed header block as a hex string.
Example:
.. code-block:: json
{
"cases":
[
{ "wire": "8285" },
{ "wire": "8583" }
]
}
The output is a JSON object. It should include a cases key and its
value is an array of JSON objects, which has at least following keys:
seq
The index of the header set in the input.
headers
A JSON array that includes decompressed name/value pairs.
wire
The compressed header block as a hex string.
header_table_size
The header table size adjusted before inflating compressed header
block.
Example:
.. code-block:: json
{
"cases":
[
{
"seq": 0,
"wire": "01881f3468e5891afcbf83868a3d856659c62e3f",
"headers": [
{
":authority": "example.org"
},
{
":method": "GET"
},
{
":path": "/"
},
{
":scheme": "https"
},
{
"user-agent": "nghttp2"
}
],
"header_table_size": 4096
}
,
{
"seq": 1,
"wire": "88448504252dd5918485",
"headers": [
{
":method": "POST"
},
{
":path": "/account"
},
{
"user-agent": "nghttp2"
},
{
":scheme": "https"
},
{
":authority": "example.org"
}
],
"header_table_size": 4096
}
]
}
The output can be used as the input for deflatehd and
inflatehd.
With the -d option, the extra header_table key is added and its
associated value includes the state of the dynamic header table after the
corresponding header set was processed. The format is the same as
deflatehd.
libnghttp2_asio: High level HTTP/2 C++ library
libnghttp2_asio is C++ library built on top of libnghttp2 and provides
high level abstraction API to build HTTP/2 applications. It depends
on the Boost::ASIO library and OpenSSL. Currently libnghttp2_asio
provides both client and server APIs.
libnghttp2_asio is not built by default. Use the --enable-asio-lib
configure flag to build libnghttp2_asio. The required Boost libraries
are:
- Boost::Asio
- Boost::System
- Boost::Thread
The server API is designed to build an HTTP/2 server very easily to utilize
C++14 anonymous functions and closures. The bare minimum example of
an HTTP/2 server looks like this:
.. code-block:: cpp
#include <iostream>
#include <nghttp2/asio_http2_server.h>
using namespace nghttp2::asio_http2;
using namespace nghttp2::asio_http2::server;
int main(int argc, char *argv[]) {
boost::system::error_code ec;
http2 server;
server.handle("/", [](const request &req, const response &res) {
res.write_head(200);
res.end("hello, world\n");
});
if (server.listen_and_serve(ec, "localhost", "3000")) {
std::cerr << "error: " << ec.message() << std::endl;
}
}
Here is sample code to use the client API:
.. code-block:: cpp
#include <iostream>
#include <nghttp2/asio_http2_client.h>
using boost::asio::ip::tcp;
using namespace nghttp2::asio_http2;
using namespace nghttp2::asio_http2::client;
int main(int argc, char *argv[]) {
boost::system::error_code ec;
boost::asio::io_service io_service;
// connect to localhost:3000
session sess(io_service, "localhost", "3000");
sess.on_connect([&sess](tcp::resolver::iterator endpoint_it) {
boost::system::error_code ec;
auto req = sess.submit(ec, "GET", "http://localhost:3000/");
req->on_response([](const response &res) {
// print status code and response header fields.
std::cerr << "HTTP/2 " << res.status_code() << std::endl;
for (auto &kv : res.header()) {
std::cerr << kv.first << ": " << kv.second.value << "\n";
}
std::cerr << std::endl;
res.on_data([](const uint8_t *data, std::size_t len) {
std::cerr.write(reinterpret_cast<const char *>(data), len);
std::cerr << std::endl;
});
});
req->on_close([&sess](uint32_t error_code) {
// shutdown session after first request was done.
sess.shutdown();
});
});
sess.on_error([](const boost::system::error_code &ec) {
std::cerr << "error: " << ec.message() << std::endl;
});
io_service.run();
}
For more details, see the documentation of libnghttp2_asio.
Python bindings
The python directory contains nghttp2 Python bindings. The
bindings currently provide HPACK compressor and decompressor classes
and an HTTP/2 server.
The extension module is called nghttp2.
make will build the bindings and target Python version is
determined by the configure script. If the detected Python version is not
what you expect, specify a path to Python executable in a PYTHON
variable as an argument to configure script (e.g., ./configure PYTHON=/usr/bin/python3.5).
The following example code illustrates basic usage of the HPACK compressor
and decompressor in Python:
.. code-block:: python
import binascii
import nghttp2
deflater = nghttp2.HDDeflater()
inflater = nghttp2.HDInflater()
data = deflater.deflate([(b'foo', b'bar'),
(b'baz', b'buz')])
print(binascii.b2a_hex(data))
hdrs = inflater.inflate(data)
print(hdrs)
The nghttp2.HTTP2Server class builds on top of the asyncio event
loop. On construction, RequestHandlerClass must be given, which
must be a subclass of nghttp2.BaseRequestHandler class.
The BaseRequestHandler class is used to handle the HTTP/2 stream.
By default, it does nothing. It must be subclassed to handle each
event callback method.
The first callback method invoked is on_headers(). It is called
when HEADERS frame, which includes the request header fields, has arrived.
If the request has a request body, on_data(data) is invoked for each
chunk of received data.
Once the entire request is received, on_request_done() is invoked.
When the stream is closed, on_close(error_code) is called.
The application can send a response using send_response() method.
It can be used in on_headers(), on_data() or
on_request_done().
The application can push resources using the push() method. It must be
used before the send_response() call.
The following instance variables are available:
client_address
Contains a tuple of the form (host, port) referring to the
client's address.
stream_id
Stream ID of this stream.
scheme
Scheme of the request URI. This is a value of :scheme header
field.
method
Method of this stream. This is a value of :method header field.
host
This is a value of :authority or host header field.
path
This is a value of :path header field.
The following example illustrates the HTTP2Server and
BaseRequestHandler usage:
.. code-block:: python
#!/usr/bin/env python
import io, ssl
import nghttp2
class Handler(nghttp2.BaseRequestHandler):
def on_headers(self):
self.push(path='/css/bootstrap.css',
request_headers = [('content-length', '3')],
status=200,
body='foo')
self.push(path='/js/bootstrap.js',
method='GET',
request_headers = [('content-length', '10')],
status=200,
body='foobarbuzz')
self.send_response(status=200,
headers = [('content-type', 'text/plain')],
body=io.BytesIO(b'nghttp2-python FTW'))
ctx = ssl.SSLContext(ssl.PROTOCOL_SSLv23)
ctx.options = ssl.OP_ALL, ssl.OP_NO_SSLv2
ctx.load_cert_chain('server.crt', 'server.key')
# give None to ssl to make the server non-SSL/TLS
server = nghttp2.HTTP2Server(('127.0.0.1', 8443), Handler, ssl=ctx)
server.serve_forever()
Contribution
[This text was composed based on 1.2. License section of curl/libcurl
project.]
When contributing with code, you agree to put your changes and new
code under the same license nghttp2 is already using unless stated and
agreed otherwise.
When changing existing source code, do not alter the copyright of
the original file(s). The copyright will still be owned by the
original creator(s) or those who have been assigned copyright by the
original author(s).
By submitting a patch to the nghttp2 project, you (or your employer, as
the case may be) agree to assign the copyright of your submission to us.
.. the above really needs to be reworded to pass legal muster.
We will credit you for your
changes as far as possible, to give credit but also to keep a trace
back to who made what changes. Please always provide us with your
full real name when contributing!
See Contribution Guidelines <https://nghttp2.org/documentation/contribute.html>_ for more
details.
Reporting vulnerability
If you find a vulnerability in our software, please send the email to
"tatsuhiro.t at gmail dot com" about its details instead of submitting
issues on github issue page. It is a standard practice not to
disclose vulnerability information publicly until a fixed version is
released, or mitigation is worked out.
In the future, we may setup a dedicated mail address for this purpose.
Release schedule
In general, we follow Semantic Versioning <http://semver.org/>_. We
release MINOR version update every month, and usually we ship it
around 25th day of every month.
We may release PATCH releases between the regular releases, mainly for
severe security bug fixes.
We have no plan to break API compatibility changes involving soname
bump, so MAJOR version will stay 1 for the foreseeable future.
License
The MIT License
