git-cache-proxy: copy starting point from userv-utils git-daemon.in, git-service.in

userv-utils has a git proxy, of which we are going to reuse some parts.
Copy them from userv-utils.git#f90cb5738a194fc1b873ffc6212f3aa9a537e2fe

diff --git a/scripts/git-daemon.in b/scripts/git-daemon.in
new file mode 100755 (executable)
index 0000000..1b1b540
--- /dev/null
+++ b/scripts/git-daemon.in
@@ -0,0 +1,87 @@
+#!/usr/bin/perl
+#
+# A git daemon with an added userv security boundary.
+#
+# This was written by Tony Finch <dot@dotat.at> and subsequently
+# heavily modified by Ian Jackson <ijackson@chiark.greenend.org.uk>
+# http://creativecommons.org/publicdomain/zero/1.0/
+
+use strict;
+use warnings;
+
+use POSIX;
+use Socket;
+use Sys::Syslog;
+
+BEGIN {
+    if ($ARGV[0] =~ s/^-L//) {
+       my $logfile= shift @ARGV;
+       open STDERR, ">> $logfile" or die $!;
+    }
+}
+
+sub ntoa {
+    my $sockaddr = shift;
+    return ('(local)') unless defined $sockaddr;
+    my ($port,$addr) = sockaddr_in $sockaddr;
+    $addr = inet_ntoa $addr;
+    return ("[$addr]:$port",$addr,$port);
+}
+our ($client,$client_addr,$client_port) = ntoa getpeername STDIN;
+our ($server,$server_addr,$server_port) = ntoa getsockname STDIN;
+our ($service,$specpath,$spechost);
+
+printf STDERR "%s [$$] %s %s\n",
+    strftime("%Y-%m-%d %H:%M:%S %Z", localtime), $server, $client;
+
+openlog 'userv-git-daemon', 'pid', 'daemon';
+sub fail { syslog 'err', "$client @_"; exit }
+
+$SIG{ALRM} = sub { fail "timeout" };
+alarm 30;
+
+sub xread {
+    my $length = shift;
+    my $buffer = "";
+    while ($length > length $buffer) {
+        my $ret = sysread STDIN, $buffer, $length, length $buffer;
+        fail "Expected $length bytes, got ".length $buffer
+                            if defined $ret and $ret == 0;
+        fail "read: $!" if not defined $ret and $! != EINTR and $! != EAGAIN;
+    }
+    return $buffer;
+}
+my $hex_len = xread 4;
+fail "Bad hex in packet length" unless $hex_len =~ m|^[0-9a-fA-F]{4}$|;
+my $line = xread -4 + hex $hex_len;
+unless (($service,$specpath,$spechost) = $line =~
+        m|^(git-[a-z-]+) /*([!-~]+)\0host=([!-~]+)\0$|) {
+    $line =~ s|[^ -~]+| |g;
+    fail "Could not parse \"$line\""
+}
+
+@@READ_URLMAP@@
+
+fail "No global mapping for $uri" unless defined $serve_user;
+
+my ($hn,$ha,$at,$naddrs,@addrs) = gethostbyname $spechost;
+fail "hostname/address mismatch ($spechost $server_addr)" unless grep {
+    $server_addr eq inet_ntoa $_
+    } @addrs;
+
+our @opts;
+
+push @opts, "-D$_=${$::{$_}}"
+    for qw(service specpath spechost
+          client client_addr client_port
+          server server_addr server_port);
+
+fail "no user $serve_user" unless getpwnam($serve_user);
+
+syslog 'notice', "$client $service $uri $serve_user";
+
+my @cmd = ('userv', '-t300', @opts, $serve_user, $service);
+no warnings; # suppress errors to stderr
+exec @cmd or fail "exec userv: $!";
+
+# end

diff --git a/scripts/git-service.in b/scripts/git-service.in
new file mode 100755 (executable)
index 0000000..2b8aff3
--- /dev/null
+++ b/scripts/git-service.in
@@ -0,0 +1,51 @@
+#!/usr/bin/perl
+#
+# userv-git-daemon service script
+#
+# This was written by Tony Finch <dot@dotat.at> and subsequently
+# heavily modified by Ian Jackson <ijackson@chiark.greenend.org.uk>
+# http://creativecommons.org/publicdomain/zero/1.0/
+
+use strict;
+use warnings;
+
+use POSIX;
+use Sys::Syslog;
+
+our ($client,$service,$specpath,$spechost,@opts);
+
+${$::{$_}} = $ENV{"USERV_U_$_"}
+       for qw(service specpath spechost client);
+
+openlog "userv-$service:$ENV{USER}", 'pid', 'daemon';
+sub fail { syslog 'err', "$client @_"; exit }
+
+@@READ_URLMAP@@
+
+fail "No user $ENV{USER} mapping for $uri" unless defined $serve_user;
+
+$serve_dir = "$ENV{HOME}/$serve_dir" unless $serve_dir =~ m|^/|;
+
+if (length $serve_repo) {
+    my $inspect= $serve_repo;
+    $inspect =~ s,^/,,;
+    fail "Bad subdirectory $serve_repo" unless $inspect =~ m/$repo_regexp/o;
+    fail "bad config - repo-regexp does not capture" unless defined $1;
+    $serve_repo= "/$1";
+}
+
+my $dir = $serve_dir.$serve_repo;
+
+my $path = $check_export ? "$dir/git-daemon-export-ok" : $dir;
+fail "$! $path" unless -e $path;
+
+syslog 'notice', "$client $uri $dir";
+
+@opts = qw( --strict )
+   if @opts == 0 and $service eq 'git-upload-pack';
+
+my @cmd = ($service =~ m|^(git)-(.*)$|, @opts, $dir);
+no warnings; # suppress errors to stderr
+exec @cmd or fail "exec $service: $!";
+
+# end