/ 
Alien-curlimpersonate-0.02
/ Alien::curlimpersonate

NAME

Alien::curlimpersonate - build and find libcurl-impersonate

SYNOPSIS

In your Makefile.PL:

use ExtUtils::MakeMaker;
use Alien::Base::Wrapper ();
use Alien::curlimpersonate ();

my %args = Alien::Base::Wrapper->new('Alien::curlimpersonate')->mm_args2;

# See "LINKING AGAINST IT" below: the wrapper emits no rpath, so add one.
my ($libdir) = Alien::curlimpersonate->dynamic_libs;
$libdir =~ s{/[^/]+$}{} if defined $libdir;
$args{LDDLFLAGS} = join ' ', grep { defined && length }
    $args{LDDLFLAGS}, ($libdir ? "-Wl,-rpath,$libdir" : ());

WriteMakefile(NAME => 'My::Module', %args);

Or just to see what was built:

use Alien::curlimpersonate;
say Alien::curlimpersonate->cflags;        # -I/.../include
say Alien::curlimpersonate->libs;          # -L/.../lib -lcurl-impersonate
say for Alien::curlimpersonate->dynamic_libs;

DESCRIPTION

Builds curl-impersonate (a patched libcurl with a bundled BoringSSL) from source and exposes its cflags/libs, so an XS module can link a libcurl that reproduces a real browser's TLS and HTTP/2 fingerprint -- JA3/JA4 and the HTTP/2 SETTINGS "Akamai" fingerprint -- rather than the one libcurl would otherwise present. See Curl::Impersonate for a Perl client built on it.

This is a source-only Alien: there is no system package of libcurl-impersonate to find, so the probe always selects a share install and the library is compiled at install time. See "SYSTEM REQUIREMENTS", because that build is neither short nor dependency-free.

The pinned version is v2.1.1, built from https://github.com/vividsnow/curl-impersonate -- a fork of https://github.com/lexiforest/curl-impersonate at that tag, carrying one commit. Upstream's CMake configure aborts under CMake 4, because curl's curl_openssl_check_exists() puts the imported targets OpenSSL::SSL and OpenSSL::Crypto into CMAKE_REQUIRED_LIBRARIES and the scratch project try_compile() generates has no such targets. CMake 3 tolerated that; CMake 4 does not. The pin returns to upstream once an equivalent fix lands there.

SYSTEM REQUIREMENTS

curl-impersonate statically builds BoringSSL, zlib, zstd, brotli, nghttp2 and ngtcp2 alongside curl itself. That needs, on top of a C and C++ compiler:

  • git -- the source is fetched by cloning the upstream repository

  • cmake 3.20 or newer -- the build is a CMake superbuild. Alien::cmake3 supplies one where the system has none, but it promises only 3.x, so the version is checked before the build starts.

  • ninja (or ninja-build) -- the curl subproject forces the Ninja generator

  • go -- BoringSSL's build generates sources with it

  • patch -- upstream patches curl and its dependencies

  • curl and make -- libidn2 is fetched and built by a shell script, separately from CMake, because CMake requires it prebuilt and will not build it

The build checks for these before it starts and names anything missing, rather than failing deep inside a compile. On Debian or Ubuntu:

apt-get install git cmake ninja-build golang-go patch curl build-essential

Expect the install to take several minutes -- around five or six on a current machine, and longer on a slow or loaded one. It is a full BoringSSL and curl build, which is why installing this dist takes far longer than the Perl code in it would suggest.

METHODS

This is an Alien::Base subclass and adds nothing of its own; the useful methods are inherited. The ones that matter here:

Alien::curlimpersonate->cflags

The include flags, as -I$prefix/include.

Alien::curlimpersonate->libs

The link flags, as -L$prefix/lib -lcurl-impersonate. No rpath -- see below.

Alien::curlimpersonate->dynamic_libs

The shared library file paths -- not directories, and including the versioned names. The order is not defined, but they all live in the same directory, so taking that of any one of them is what you want for an rpath.

LINKING AGAINST IT

libs deliberately carries no -Wl,-rpath. Alien::Base relocates the -L it emits when the Alien is installed to its final location, but it does not relocate an rpath -- so an rpath baked in here would point at the staging directory and be wrong by the time anyone links against it.

The consequence is that a consumer linking with libs alone produces an extension that builds cleanly and then fails at runtime with something like libcurl-impersonate.so.4: cannot open shared object file, unless LD_LIBRARY_PATH happens to be set.

So add the rpath yourself, against the resolved library directory, as the SYNOPSIS shows: take dynamic_libs, strip the filename, and pass -Wl,-rpath,$libdir. Curl::Impersonate's Makefile.PL is a working example.

CAVEATS

The version is pinned exactly. That is deliberate -- the whole point of this Alien is a reproducible fingerprint, and the set of impersonation targets changes between releases -- but it means a newer curl-impersonate needs a new release of this dist rather than a rebuild. It is also load-bearing: upstream 2.0.0 replaced the autotools build with CMake outright, so a floating pin would have broken the build the moment that tag was cut.

SEE ALSO

Curl::Impersonate, Alien::Base, Alien::Build, https://github.com/lexiforest/curl-impersonate

AUTHOR

vividsnow

LICENSE

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

The library it builds, curl-impersonate, is distributed under its own terms; see the upstream project for details.