This is an experimental implementation of Google's SPDY protocol in C.
This library provides SPDY version 2 and 3 framing layer implementation. It does not perform any I/O operations. When the library needs them, it calls the callback functions provided by the application. It also does not include any event polling mechanism, so the application can freely choose the way of handling events. This library code does not depend on any particular SSL library (except for example programs which depend on OpenSSL 1.0.1 or later).
Most of the SPDY/2 and SPDY/3 functionality has been implemented. In both versions, the direct support of server-push has not been available yet. The application can achieve server-push using primitive APIs though.
As described below, we can create SPDY client and server with the current Spdylay API.
The following packages are needed to build the library:
- pkg-config >= 0.20
- zlib >= 1.2.3
To build and run the unit test programs, the following packages are needed:
- cunit >= 2.1
To build and run the example programs, the following packages are needed:
- OpenSSL >= 1.0.1
To enable -a option (getting linked assets from the downloaded
resouce) in spdycat (one of the example program), the following
packages are needed:
- libxml2 >= 2.7.7
Building from git is easy, but please be sure that at least autoconf 2.68 is used:
$ autoreconf -i $ automake $ autoconf $ ./configure $ make
To build documentation, run:
$ make html
The documents will be generated under doc/manual/html/.
The generated documents will not be installed with make install.
The public API reference is available on online. Visit http://spdylay.sourceforge.net/. All public APIs are in spdylay/spdylay.h. All public API functions as well as the callback function typedefs are documented.
examples directory contains SPDY client and server implementation using Spdylay. These programs are intended to make sure that Spdylay API is acutally usable for real implementation and also for debugging purposes. Please note that OpenSSL with NPN support is required in order to build and run these programs. At the time of this writing, the OpenSSL 1.0.1 supports NPN.
The SPDY client is called spdycat. It is a dead simple downloader
like wget/curl. It connects to SPDY server and gets resources given in
the command-line:
$ examples/spdycat -h
Usage: spdycat [-Oansv23] [-t <SECONDS>] [-w <WINDOW_BITS>] [--cert=<CERT>]
[--key=<KEY>] <URI>...
OPTIONS:
-v, --verbose Print debug information such as reception/
transmission of frames and name/value pairs.
-n, --null-out Discard downloaded data.
-O, --remote-name Save download data in the current directory.
The filename is dereived from URI. If URI
ends with '/', 'index.html' is used as a
filename. Not implemented yet.
-2, --spdy2 Only use SPDY/2.
-3, --spdy3 Only use SPDY/3.
-t, --timeout=<N> Timeout each request after <N> seconds.
-w, --window-bits=<N>
Sets the initial window size to 2**<N>.
-a, --get-assets Download assets such as stylesheets, images
and script files linked from the downloaded
resource. Only links whose origins are the
same with the linking resource will be
downloaded.
-s, --stat Print statistics.
--cert=<CERT> Use the specified client certificate file.
The file must be in PEM format.
--key=<KEY> Use the client private key file. The file
must be in PEM format.
$ examples/spdycat -nv https://www.google.com/
[ 0.025] NPN select next protocol: the remote server offers:
* spdy/3
* spdy/2
* http/1.1
NPN selected the protocol: spdy/3
[ 0.035] recv SETTINGS frame <version=3, flags=0, length=20>
(niv=2)
[4(1):100]
[7(0):12288]
[ 0.035] send SYN_STREAM frame <version=3, flags=1, length=106>
(stream_id=1, assoc_stream_id=0, pri=3)
:host: www.google.com
:method: GET
:path: /
:scheme: https
:version: HTTP/1.1
accept: */*
user-agent: spdylay/0.2.0
[ 0.077] recv SYN_REPLY frame <version=3, flags=0, length=558>
(stream_id=1)
:status: 302 Found
:version: HTTP/1.1
cache-control: private
content-length: 222
content-type: text/html; charset=UTF-8
date: Sun, 13 May 2012 08:02:54 GMT
location: https://www.google.co.jp/
server: gws
x-frame-options: SAMEORIGIN
x-xss-protection: 1; mode=block
[ 0.077] recv DATA frame (stream_id=1, flags=1, length=222)
[ 0.077] send GOAWAY frame <version=3, flags=0, length=8>
(last_good_stream_id=0)
SPDY server is called spdyd and serves static files. It is single
threaded and multiplexes connections using non-blocking socket. The
static files are read using blocking I/O system call, read(2). It
speaks SPDY/2 and SPDY/3:
$ examples/spdyd --htdocs=/your/htdocs/ -v 3000 server.key server.crt
IPv4: listen on port 3000
IPv6: listen on port 3000
The negotiated next protocol: spdy/3
[id=1] [ 17.456] send SETTINGS frame <version=3, flags=0, length=12>
(niv=1)
[4(0):100]
[id=1] [ 17.457] recv SYN_STREAM frame <version=3, flags=1, length=108>
(stream_id=1, assoc_stream_id=0, pri=3)
:host: localhost:3000
:method: GET
:path: /README
:scheme: https
:version: HTTP/1.1
accept: */*
user-agent: spdylay/0.2.0
[id=1] [ 17.457] send SYN_REPLY frame <version=3, flags=0, length=113>
(stream_id=1)
:status: 200 OK
:version: HTTP/1.1
cache-control: max-age=3600
content-length: 15
date: Sun, 13 May 2012 08:06:12 GMT
last-modified: Tue, 17 Jan 2012 15:39:01 GMT
server: spdyd spdylay/0.2.0
[id=1] [ 17.467] send DATA frame (stream_id=1, flags=0, length=15)
[id=1] [ 17.467] send DATA frame (stream_id=1, flags=1, length=0)
[id=1] [ 17.468] stream_id=1 closed
[id=1] [ 17.468] recv GOAWAY frame <version=3, flags=0, length=8>
(last_good_stream_id=0)
[id=1] [ 17.468] closed
Currently, spdyd needs epoll or kqueue.
There is another SPDY server called spdynative, which is
node.native style simple SPDY
server:
#include <iostream>
#include "spdy.h"
int main()
{
spdy server;
if(!server.listen("localhost", 8080, "server.key", "server.crt",
[](request& req, response& res) {
res.set_status(200);
res.set_header("content-type", "text/plain");
res.end("C++ FTW\n");
}))
return EXIT_FAILURE;
std::cout << "Server running at http://localhost:8080/" << std::endl;
return reactor::run(server);
}
Don't expect much from spdynative. It is just an example and does
not support asynchronous I/O at all.
If you are looking for the example program written in C, see
spdycli which is the simple SPDY client.