| 1 | #!/usr/bin/perl |
| 2 | # |
| 3 | # A git daemon with an added userv security boundary. |
| 4 | # |
| 5 | # This was written by Tony Finch <dot@dotat.at> and subsequently |
| 6 | # heavily modified by Ian Jackson <ijackson@chiark.greenend.org.uk> |
| 7 | # http://creativecommons.org/publicdomain/zero/1.0/ |
| 8 | |
| 9 | use strict; |
| 10 | use warnings; |
| 11 | |
| 12 | use POSIX; |
| 13 | use Socket; |
| 14 | use Sys::Syslog; |
| 15 | |
| 16 | BEGIN { |
| 17 | if ($ARGV[0] =~ s/^-L//) { |
| 18 | my $logfile= shift @ARGV; |
| 19 | open STDERR, ">> $logfile" or die $!; |
| 20 | } |
| 21 | } |
| 22 | |
| 23 | sub ntoa { |
| 24 | my $sockaddr = shift; |
| 25 | return ('(local)') unless defined $sockaddr; |
| 26 | my ($port,$addr) = sockaddr_in $sockaddr; |
| 27 | $addr = inet_ntoa $addr; |
| 28 | return ("[$addr]:$port",$addr,$port); |
| 29 | } |
| 30 | our ($client,$client_addr,$client_port) = ntoa getpeername STDIN; |
| 31 | our ($server,$server_addr,$server_port) = ntoa getsockname STDIN; |
| 32 | our ($service,$specpath,$spechost); |
| 33 | |
| 34 | printf STDERR "%s [$$] %s %s\n", |
| 35 | strftime("%Y-%m-%d %H:%M:%S %Z", localtime), $server, $client; |
| 36 | |
| 37 | openlog 'userv-git-daemon', 'pid', 'daemon'; |
| 38 | sub fail { syslog 'err', "$client @_"; exit } |
| 39 | |
| 40 | $SIG{ALRM} = sub { fail "timeout" }; |
| 41 | alarm 30; |
| 42 | |
| 43 | sub xread { |
| 44 | my $length = shift; |
| 45 | my $buffer = ""; |
| 46 | while ($length > length $buffer) { |
| 47 | my $ret = sysread STDIN, $buffer, $length, length $buffer; |
| 48 | fail "Expected $length bytes, got ".length $buffer |
| 49 | if defined $ret and $ret == 0; |
| 50 | fail "read: $!" if not defined $ret and $! != EINTR and $! != EAGAIN; |
| 51 | } |
| 52 | return $buffer; |
| 53 | } |
| 54 | my $hex_len = xread 4; |
| 55 | fail "Bad hex in packet length" unless $hex_len =~ m|^[0-9a-fA-F]{4}$|; |
| 56 | my $line = xread -4 + hex $hex_len; |
| 57 | unless (($service,$specpath,$spechost) = $line =~ |
| 58 | m|^(git-[a-z-]+) /*([!-~]+)\0host=([!-~]+)\0$|) { |
| 59 | $line =~ s|[^ -~]+| |g; |
| 60 | fail "Could not parse \"$line\"" |
| 61 | } |
| 62 | |
| 63 | @@READ_URLMAP@@ |
| 64 | |
| 65 | fail "No global mapping for $uri" unless defined $serve_user; |
| 66 | |
| 67 | my ($hn,$ha,$at,$naddrs,@addrs) = gethostbyname $spechost; |
| 68 | fail "hostname/address mismatch ($spechost $server_addr)" unless grep { |
| 69 | $server_addr eq inet_ntoa $_ |
| 70 | } @addrs; |
| 71 | |
| 72 | our @opts; |
| 73 | |
| 74 | push @opts, "-D$_=${$::{$_}}" |
| 75 | for qw(service specpath spechost |
| 76 | client client_addr client_port |
| 77 | server server_addr server_port); |
| 78 | |
| 79 | fail "no user $serve_user" unless getpwnam($serve_user); |
| 80 | |
| 81 | syslog 'notice', "$client $service $uri $serve_user"; |
| 82 | |
| 83 | my @cmd = ('userv', '-t300', @opts, $serve_user, $service); |
| 84 | no warnings; # suppress errors to stderr |
| 85 | exec @cmd or fail "exec userv: $!"; |
| 86 | |
| 87 | # end |