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curl / Docs / Protocols / HTTP/3 with curl

HTTP3 (and QUIC)

Resources

HTTP/3 Explained - the online free book describing the protocols involved.

QUIC implementation - the wiki page describing the plan for how to support QUIC and HTTP/3 in curl and libcurl.

quicwg.org - home of the official protocol drafts

QUIC libraries

QUIC libraries we are experimenting with:

ngtcp2

quiche

msquic & msh3

Experimental

HTTP/3 and QUIC support in curl is considered EXPERIMENTAL until further notice. It needs to be enabled at build-time.

Further development and tweaking of the HTTP/3 support in curl will happen in the master branch using pull-requests, just like ordinary changes.

ngtcp2 version

Build with OpenSSL

Build (patched) OpenSSL

 % git clone --depth 1 -b openssl-3.0.0+quic https://github.com/quictls/openssl
 % cd openssl
 % ./config enable-tls1_3 --prefix=<somewhere1>
 % make
 % make install

Build nghttp3

 % cd ..
 % git clone https://github.com/ngtcp2/nghttp3
 % cd nghttp3
 % autoreconf -fi
 % ./configure --prefix=<somewhere2> --enable-lib-only
 % make
 % make install

Build ngtcp2

 % cd ..
 % git clone https://github.com/ngtcp2/ngtcp2
 % cd ngtcp2
 % autoreconf -fi
 % ./configure PKG_CONFIG_PATH=<somewhere1>/lib/pkgconfig:<somewhere2>/lib/pkgconfig LDFLAGS="-Wl,-rpath,<somewhere1>/lib" --prefix=<somewhere3> --enable-lib-only
 % make
 % make install

Build curl

 % cd ..
 % git clone https://github.com/curl/curl
 % cd curl
 % autoreconf -fi
 % LDFLAGS="-Wl,-rpath,<somewhere1>/lib" ./configure --with-openssl=<somewhere1> --with-nghttp3=<somewhere2> --with-ngtcp2=<somewhere3>
 % make
 % make install

For OpenSSL 3.0.0 or later builds on Linux for x86_64 architecture, substitute all occurrences of "/lib" with "/lib64"

Build with GnuTLS

Build GnuTLS

 % git clone --depth 1 https://gitlab.com/gnutls/gnutls.git
 % cd gnutls
 % ./bootstrap
 % ./configure --prefix=<somewhere1>
 % make
 % make install

Build nghttp3

 % cd ..
 % git clone https://github.com/ngtcp2/nghttp3
 % cd nghttp3
 % autoreconf -fi
 % ./configure --prefix=<somewhere2> --enable-lib-only
 % make
 % make install

Build ngtcp2

 % cd ..
 % git clone https://github.com/ngtcp2/ngtcp2
 % cd ngtcp2
 % autoreconf -fi
 % ./configure PKG_CONFIG_PATH=<somewhere1>/lib/pkgconfig:<somewhere2>/lib/pkgconfig LDFLAGS="-Wl,-rpath,<somewhere1>/lib" --prefix=<somewhere3> --enable-lib-only --with-gnutls
 % make
 % make install

Build curl

 % cd ..
 % git clone https://github.com/curl/curl
 % cd curl
 % autoreconf -fi
 % ./configure --without-openssl --with-gnutls=<somewhere1> --with-nghttp3=<somewhere2> --with-ngtcp2=<somewhere3>
 % make
 % make install

quiche version

build

Build quiche and BoringSSL:

 % git clone --recursive https://github.com/cloudflare/quiche
 % cd quiche
 % cargo build --package quiche --release --features ffi,pkg-config-meta,qlog
 % mkdir quiche/deps/boringssl/src/lib
 % ln -vnf $(find target/release -name libcrypto.a -o -name libssl.a) quiche/deps/boringssl/src/lib/

Build curl:

 % cd ..
 % git clone https://github.com/curl/curl
 % cd curl
 % autoreconf -fi
 % ./configure LDFLAGS="-Wl,-rpath,$PWD/../quiche/target/release" --with-openssl=$PWD/../quiche/quiche/deps/boringssl/src --with-quiche=$PWD/../quiche/target/release
 % make
 % make install

If make install results in Permission denied error, you will need to prepend it with sudo.

msh3 (msquic) version

Build Linux (with quictls fork of OpenSSL)

Build msh3:

 % git clone --depth 1 --recursive https://github.com/nibanks/msh3
 % cd msh3 && mkdir build && cd build
 % cmake -G 'Unix Makefiles' -DCMAKE_BUILD_TYPE=RelWithDebInfo ..
 % cmake --build .
 % cmake --install .

Build curl:

 % git clone https://github.com/curl/curl
 % cd curl
 % autoreconf -fi
 % ./configure LDFLAGS="-Wl,-rpath,/usr/local/lib" --with-msh3=/usr/local --with-openssl
 % make
 % make install

Run from /usr/local/bin/curl.

Build Windows

Build msh3:

 % git clone --depth 1 --recursive https://github.com/nibanks/msh3
 % cd msh3 && mkdir build && cd build
 % cmake -G 'Visual Studio 17 2022' -DCMAKE_BUILD_TYPE=RelWithDebInfo ..
 % cmake --build . --config Release
 % cmake --install . --config Release

Note - On Windows, Schannel will be used for TLS support by default. If you with to use (the quictls fork of) OpenSSL, specify the -DQUIC_TLS=openssl option to the generate command above. Also note that OpenSSL brings with it an additional set of build dependencies not specified here.

Build curl (in Visual Studio Command prompt):

 % git clone https://github.com/curl/curl
 % cd curl/winbuild
 % nmake /f Makefile.vc mode=dll WITH_MSH3=dll MSH3_PATH="C:/Program Files/msh3" MACHINE=x64

Note - If you encounter a build error with tool_hugehelp.c being missing, rename tool_hugehelp.c.cvs in the same directory to tool_hugehelp.c and then run nmake again.

Run in the C:/Program Files/msh3/lib directory, copy curl.exe to that directory, or copy msquic.dll and msh3.dll from that directory to the curl.exe directory. For example:

 % C:\Program Files\msh3\lib> F:\curl\builds\libcurl-vc-x64-release-dll-ipv6-sspi-schannel-msh3\bin\curl.exe --http3 https://www.google.com

--http3

Use HTTP/3 directly:

curl --http3 https://nghttp2.org:4433/

Upgrade via Alt-Svc:

curl --alt-svc altsvc.cache https://quic.aiortc.org/

See this list of public HTTP/3 servers

Known Bugs

Check out the list of known HTTP3 bugs.

HTTP/3 Test server

This is not advice on how to run anything in production. This is for development and experimenting.

Prerequisite(s)

An existing local HTTP/1.1 server that hosts files. Preferably also a few huge ones. You can easily create huge local files like truncate -s=8G 8GB - they are huge but do not occupy that much space on disk since they are just big holes.

In my Debian setup I just installed apache2. It runs on port 80 and has a document root in /var/www/html. I can get the 8GB file from it with curl localhost/8GB -o dev/null

In this description we setup and run an HTTP/3 reverse-proxy in front of the HTTP/1 server.

Setup

You can select either or both of these server solutions.

nghttpx

Get, build and install quictls, nghttp3 and ngtcp2 as described above.

Get, build and install nghttp2:

git clone https://github.com/nghttp2/nghttp2.git
cd nghttp2
autoreconf -fi
PKG_CONFIG_PATH=$PKG_CONFIG_PATH:/home/daniel/build-quictls/lib/pkgconfig:/home/daniel/build-nghttp3/lib/pkgconfig:/home/daniel/build-ngtcp2/lib/pkgconfig  LDFLAGS=-L/home/daniel/build-quictls/lib CFLAGS=-I/home/daniel/build-quictls/include ./configure --enable-maintainer-mode --prefix=/home/daniel/build-nghttp2 --disable-shared --enable-app --enable-http3 --without-jemalloc --without-libxml2 --without-systemd
make && make install

Run the local h3 server on port 9443, make it proxy all traffic through to HTTP/1 on localhost port 80. For local toying, we can just use the test cert that exists in curl's test dir.

CERT=$CURLSRC/tests/stunnel.pem
$HOME/bin/nghttpx $CERT $CERT --backend=localhost,80   --frontend="localhost,9443;quic"

Caddy

Install caddy, you can even put the single binary in a separate directory if you prefer.

In the same directory you put caddy, create a Caddyfile with the following content to run an HTTP/3 reverse-proxy on port 7443:

{
    auto_https disable_redirects
    servers :7443 {
        protocol {
            experimental_http3
        }
    }
}
localhost:7443 {
    reverse_proxy localhost:80
}

Then run caddy:

./caddy start