GHA: scan git repository and detect unvetted binary files

The only binary-looking files that are accepted in the git repository
need to match the checksums in the sha256sum file
".github/scripts/binarycheck.sums".

This is done to make sure that no one has planted any hidden (encrypted)
potentially dangerous payload in the tree.

Closes #14333

.github/scripts/binarycheck.pl

@@ -0,0 +1,115 @@
+#!/usr/bin/env perl
+#***************************************************************************
+#                                  _   _ ____  _
+#  Project                     ___| | | |  _ \| |
+#                             / __| | | | |_) | |
+#                            | (__| |_| |  _ <| |___
+#                             \___|\___/|_| \_\_____|
+#
+# Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
+#
+# This software is licensed as described in the file COPYING, which
+# you should have received as part of this distribution. The terms
+# are also available at https://curl.se/docs/copyright.html.
+#
+# You may opt to use, copy, modify, merge, publish, distribute and/or sell
+# copies of the Software, and permit persons to whom the Software is
+# furnished to do so, under the terms of the COPYING file.
+#
+# This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+# KIND, either express or implied.
+#
+# SPDX-License-Identifier: curl
+#
+###########################################################################
+
+# This scripts scans the entire git repository for binary files.
+#
+# All files in the git repo that contain signs of being binary are then
+# collected and a sha256sum is generated for all of them. That summary is then
+# compared to the list of pre-vetted files so that only the exact copies of
+# already scrutinized files are deemed okay to "appear binary".
+#
+
+use strict;
+use warnings;
+
+my $root = ".";
+my $sumsfile = ".github/scripts/binarycheck.sums";
+if($ARGV[0]) {
+    $root = $ARGV[0];
+}
+
+my @bin;
+my %known;
+my $error = 0;
+
+sub knownbins {
+    open(my $mh, "<", "$sumsfile") ||
+        die "can't read known binaries";
+    while(<$mh>) {
+        my $l = $_;
+        chomp $l;
+        if($l =~ /^([a-f0-9]+)  (.*)/) {
+            my ($sum, $file) = ($1, $2);
+            $known{$file} = 1;
+        }
+        elsif($l =~ /^#/) {
+            # skip comments
+        }
+        else {
+            print STDERR "suspicious line in $sumsfile\n";
+            $error++;
+        }
+    }
+    close($mh);
+}
+
+sub checkfile {
+    my ($file) = @_;
+    open(my $mh, "<", "$file") || die "can't read $file";
+    my $line = 0;
+    while(<$mh>) {
+        my $l = $_;
+        $line++;
+        if($l =~ /([\x00-\x08\x0b\x0c\x0e-\x1f\x7f])/) {
+            push @bin, $file;
+
+            if(!$known{$file}) {
+                printf STDERR "$file:$line has unknown binary contents\n";
+                $error++;
+            }
+            last;
+        }
+    }
+    close($mh);
+}
+
+my @files = `git ls-files -- $root`;
+
+if(scalar(@files) < 3000) {
+    # this means this is not the git source code repository or that git does
+    # not work, error out!
+    print STDERR "too few files in the git repository!\n";
+    exit 1;
+}
+
+knownbins();
+
+if(scalar(keys %known) < 10) {
+    print STDERR "too few known binaries in $sumsfile\n";
+    exit 2;
+}
+
+for my $f (@files) {
+    chomp $f;
+    checkfile("$root/$f");
+}
+
+my $check=system("sha256sum -c $sumsfile");
+if($check) {
+    print STDERR "sha256sum detected a problem\n";
+    $error++;
+}
+
+exit $error;

.github/scripts/binarycheck.sums

@@ -0,0 +1,25 @@
+# Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
+# SPDX-License-Identifier: curl
+339d83446859f914867398046270d40b6ca7538c0adfef45eb62c8a16abb6a51  ./tests/certs/EdelCurlRoot-ca.der
+c819fdeb4a6d27dde78895c2f3ed6467a31b332e72781e4ce6e11400bae9df3c  ./tests/certs/Server-localhost-firstSAN-sv.der
+f95d6b18fa02a0e2d98ed851cfa2f0b4b57d67fe8676ce4b1f78fc294ac22307  ./tests/certs/Server-localhost-firstSAN-sv.pub.der
+3520cdc749d32bbe93276be4d8f714e24b5b882284566966f28361f1cb8a4d1c  ./tests/certs/Server-localhost-lastSAN-sv.der
+d623be406f9c02b28b2f2a376b3d8e06ed25335b7cbf96cb2c8de9357a09250d  ./tests/certs/Server-localhost-lastSAN-sv.pub.der
+d89d7ea295af4baa5f57304c69570b4a71f2dd4f9fe06350ab50041287b6910a  ./tests/certs/Server-localhost-sv.der
+0005032e4e1cf7cc5c1540ef03d8bf32703d1ee3b4dc83e2d79afe0b1f4e5e77  ./tests/certs/Server-localhost-sv.pub.der
+5b22627a94c67159a18203ab5cd96b739188188cec61e73a444b2290e14d3d82  ./tests/certs/Server-localhost.nn-sv.der
+611cbce062c9c6924119d7498e19eacdee4326190e516cad9c212a4b4bb49930  ./tests/certs/Server-localhost.nn-sv.pub.der
+6eb66ef346068b4d9bbcc7c79244c48d3a4877f08618ff379b40ae02e067ba09  ./tests/certs/Server-localhost0h-sv.der
+b967734c9bfe3d7a1a7795f348f0bce4d9ba15ca9590697ef2d4d15b92822db0  ./tests/certs/Server-localhost0h-sv.pub.der
+6605cac758b09a954b12c2970c7d7a00f92658fc3ced250b281ae066e3ea6a73  ./tests/certs/stunnel-sv.der
+2e9634d7d8387fbffd1fe43e030746610b2fc088f627333a9b58e5cb224ad6ba  ./tests/certs/stunnel-sv.pub.der
+9e38c1fb0a151c4e23c8abddc44711c12afb3161c6b2a1c68e1bb2b0a4484e3b  ./tests/data/test1425
+26ee981dcb84b6a2adce601084b78e6b787b54a2a997549582a8bd42087ab51b  ./tests/data/test1426
+d640923e45809a3fe277e0af90459d82d32603aacc7b8db88754fcb335bf98df  ./tests/data/test1531
+6f51bc318104fb5fe4b6013fc4e8e1c3c8dec1819202e8ea025bdbc4bbc8c02d  ./tests/data/test1938
+28a957ec3397881bbafd0d97879cedfd475bcd1ece903e531576affd7aa3865c  ./tests/data/test2080
+db99126801fd5e7cb0c1ec1a0078e5599038c8c07073f3d62ed51f155e0e3d38  ./tests/data/test262
+2d073a52984bab1f196d80464ea8ab6dafd887bd5fee9ed58603f8510df0c6a5  ./tests/data/test35
+4cc9fd6f31d0bb4dcb38e1565796e7ec5e48ea5ac9d3c1101de576be618786ba  ./tests/data/test463
+d655a29dcf2423b420b508c9e381b0fad0b88feb74caa8978725e22c9f7c374d  ./tests/data/test467
+8644ccf85e552755bf65faf2991d84f19523919379ec2cf195841a4cabe1507b  ./tests/data/test545

.github/workflows/binarycheck.yml

@@ -0,0 +1,23 @@
+# Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
+#
+# SPDX-License-Identifier: curl
+
+name: bincheck
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+    branches:
+      - master
+
+permissions: {}
+
+jobs:
+  check:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@692973e3d937129bcbf40652eb9f2f61becf3332 # v4
+
+      - name: Check for binary files
+        run: ./.github/scripts/binarycheck.pl