Add Git credential helper that can parse netrc/authinfo files. This credential helper support multiple files, returning the first one that matches. It checks file permissions and owner. For *.gpg files, it will run GPG to decrypt the file. Signed-off-by: Ted Zlatanov <tzz@xxxxxxxxxxxx> --- Changes since PATCHv4: - indentation and brace fixes - test makefile uses "=>" as the decorative prefix - documentation fixes about order and show query with "hostname" - add --insecure to ignore owner and permission checks - check permissions just once and only for unencrypted files - change IO::File to simple open() and quote $file - fixed macdef buglet from Net::Netrc - ignore 'default' entries contrib/credential/netrc/Makefile | 12 + contrib/credential/netrc/git-credential-netrc | 424 +++++++++++++++++++++++++ 2 files changed, 436 insertions(+), 0 deletions(-) create mode 100644 contrib/credential/netrc/Makefile create mode 100755 contrib/credential/netrc/git-credential-netrc diff --git a/contrib/credential/netrc/Makefile b/contrib/credential/netrc/Makefile new file mode 100644 index 0000000..18a924f --- /dev/null +++ b/contrib/credential/netrc/Makefile @@ -0,0 +1,12 @@ +test_netrc: + @(echo "bad data" | ./git-credential-netrc -f A -d -v) || echo "Bad invocation test, ignoring failure" + @echo "=> Silent invocation... nothing should show up here with a missing file" + @echo "bad data" | ./git-credential-netrc -f A get + @echo "=> Back to noisy: -v and -d used below, missing file" + echo "bad data" | ./git-credential-netrc -f A -d -v get + @echo "=> Look for any entry in the default file set" + echo "" | ./git-credential-netrc -d -v get + @echo "=> Look for github.com in the default file set" + echo "host=google.com" | ./git-credential-netrc -d -v get + @echo "=> Look for a nonexistent machine in the default file set" + echo "host=korovamilkbar" | ./git-credential-netrc -d -v get diff --git a/contrib/credential/netrc/git-credential-netrc b/contrib/credential/netrc/git-credential-netrc new file mode 100755 index 0000000..8298564 --- /dev/null +++ b/contrib/credential/netrc/git-credential-netrc @@ -0,0 +1,424 @@ +#!/usr/bin/perl + +use strict; +use warnings; + +use Getopt::Long; +use File::Basename; + +my $VERSION = "0.1"; + +my %options = ( + help => 0, + debug => 0, + verbose => 0, + insecure => 0, + file => [], + + # identical token maps, e.g. host -> host, will be inserted later + tmap => { + port => 'protocol', + machine => 'host', + path => 'path', + login => 'username', + user => 'username', + password => 'password', + } + ); + +# Map each credential protocol token to itself on the netrc side. +foreach (values %{$options{tmap}}) { + $options{tmap}->{$_} = $_; +} + +# Now, $options{tmap} has a mapping from the netrc format to the Git credential +# helper protocol. + +# Next, we build the reverse token map. + +# When $rmap{foo} contains 'bar', that means that what the Git credential helper +# protocol calls 'bar' is found as 'foo' in the netrc/authinfo file. Keys in +# %rmap are what we expect to read from the netrc/authinfo file. + +my %rmap; +foreach my $k (keys %{$options{tmap}}) { + push @{$rmap{$options{tmap}->{$k}}}, $k; +} + +Getopt::Long::Configure("bundling"); + +# TODO: maybe allow the token map $options{tmap} to be configurable. +GetOptions(\%options, + "help|h", + "debug|d", + "insecure|k", + "verbose|v", + "file|f=s@", + ); + +if ($options{help}) { + my $shortname = basename($0); + $shortname =~ s/git-credential-//; + + print <<EOHIPPUS; + +$0 [-f AUTHFILE1] [-f AUTHFILEN] [-d] [-v] [-k] get + +Version $VERSION by tzz\@lifelogs.com. License: BSD. + +Options: + + -f|--file AUTHFILE : specify netrc-style files. Files with the .gpg extension + will be decrypted by GPG before parsing. Multiple -f + arguments are OK. They are processed in order, and the + first matching entry found is returned via the credential + helper protocol (see below). + + -k|--insecure : ignore bad file ownership or permissions + + -d|--debug : turn on debugging (developer info) + + -v|--verbose : be more verbose (show files and information found) + +To enable this credential helper: + + git config credential.helper '$shortname -f AUTHFILE1 -f AUTHFILE2' + +(Note that Git will prepend "git-credential-" to the helper name and look for it +in the path.) + +...and if you want lots of debugging info: + + git config credential.helper '$shortname -f AUTHFILE -d' + +...or to see the files opened and data found: + + git config credential.helper '$shortname -f AUTHFILE -v' + +Only "get" mode is supported by this credential helper. It opens every AUTHFILE +and looks for the first entry that matches the requested search criteria: + + 'port|protocol': + The protocol that will be used (e.g., https). (protocol=X) + + 'machine|host': + The remote hostname for a network credential. (host=X) + + 'path': + The path with which the credential will be used. (path=X) + + 'login|user|username': + The credential’s username, if we already have one. (username=X) + +Thus, when we get this query on STDIN: + +host=github.com +protocol=https +username=tzz + +this credential helper will look for the first entry in every AUTHFILE that +matches + +machine github.com port https login tzz + +OR + +machine github.com protocol https login tzz + +OR... etc. acceptable tokens as listed above. Any unknown tokens are +simply ignored. + +Then, the helper will print out whatever tokens it got from the entry, including +"password" tokens, mapping back to Git's helper protocol; e.g. "port" is mapped +back to "protocol". Any redundant entry tokens (part of the original query) are +skipped. + +Again, note that only the first matching entry from all the AUTHFILEs, processed +in the sequence given on the command line, is used. + +Netrc/authinfo tokens can be quoted as 'STRING' or "STRING". + +No caching is performed by this credential helper. + +EOHIPPUS + + exit 0; +} + +my $mode = shift @ARGV; + +# Credentials must get a parameter, so die if it's missing. +die "Syntax: $0 [-f AUTHFILE1] [-f AUTHFILEN] [-d] get" unless defined $mode; + +# Only support 'get' mode; with any other unsupported ones we just exit. +exit 0 unless $mode eq 'get'; + +my $files = $options{file}; + +# if no files were given, use a predefined list. +# note that .gpg files come first +unless (scalar @$files) { + my @candidates = qw[ + ~/.authinfo.gpg + ~/.netrc.gpg + ~/.authinfo + ~/.netrc + ]; + + $files = $options{file} = [ map { glob $_ } @candidates ]; +} + +my $query = read_credential_data_from_stdin(); + +FILE: +foreach my $file (@$files) { + my $gpgmode = $file =~ m/\.gpg$/; + unless (-r $file) { + log_verbose("Unable to read $file; skipping it"); + next FILE; + } + + # the following check is copied from Net::Netrc, for non-GPG files + # OS/2 and Win32 do not handle stat in a way compatable with this check :-( + unless ($gpgmode || $options{insecure} || + $^O eq 'os2' + || $^O eq 'MSWin32' + || $^O eq 'MacOS' + || $^O =~ /^cygwin/) { + my @stat = stat($file); + + if (@stat) { + if ($stat[2] & 077) { + log_verbose("Insecure $file (mode=%04o); skipping it", + $stat[2] & 07777); + next FILE; + } + + if ($stat[4] != $<) { + log_verbose("Not owner of $file; skipping it"); + next FILE; + } + } + } + + my @entries = load_netrc($file, $gpgmode); + + unless (scalar @entries) { + if ($!) { + log_verbose("Unable to open $file: $!"); + } + else { + log_verbose("No netrc entries found in $file"); + } + + next FILE; + } + + my $entry = find_netrc_entry($query, @entries); + if ($entry) { + print_credential_data($entry, $query); + # we're done! + last FILE; + } +} + +exit 0; + +sub load_netrc { + my $file = shift @_; + my $gpgmode = shift @_; + + my $io; + if ($gpgmode) { + # typical shell character escapes from http://www.slac.stanford.edu/slac/www/resource/how-to-use/cgi-rexx/cgi-esc.html + my $f = $file; + $f =~ s/([;<>\*\|`&\$!#\(\)\[\]\{\}:'"])/\\$1/g; + # GPG doesn't work well with 2- or 3-argument open + my $cmd = "gpg --decrypt $f"; + log_verbose("Using GPG to open $file: [$cmd]"); + open $io, "$cmd|"; + } + else { + log_verbose("Opening $file..."); + open $io, '<', $file; + } + + # nothing to do if the open failed (we log the error later) + return unless $io; + + # Net::Netrc does this, but the functionality is merged with the file + # detection logic, so we have to extract just the part we need + my @netrc_entries = net_netrc_loader($io); + + # these entries will use the credential helper protocol token names + my @entries; + + foreach my $nentry (@netrc_entries) { + my %entry; + my $num_port; + + if (defined $nentry->{port} && $nentry->{port} =~ m/^\d+$/) { + $num_port = $nentry->{port}; + delete $nentry->{port}; + } + + # create the new entry for the credential helper protocol + $entry{$options{tmap}->{$_}} = $nentry->{$_} foreach keys %$nentry; + + # for "host X port Y" where Y is an integer (captured by + # $num_port above), set the host to "X:Y" + if (defined $entry{host} && defined $num_port) { + $entry{host} = join(':', $entry{host}, $num_port); + } + + push @entries, \%entry; + } + + return @entries; +} + +sub net_netrc_loader { + my $fh = shift @_; + my @entries; + my ($mach, $macdef, $tok, @tok); + + LINE: + while (<$fh>) { + undef $macdef if /\A\n\Z/; + + if ($macdef) { + next LINE; + } + + s/^\s*//; + chomp; + + while (length && s/^("((?:[^"]+|\\.)*)"|((?:[^\\\s]+|\\.)*))\s*//) { + (my $tok = $+) =~ s/\\(.)/$1/g; + push(@tok, $tok); + } + + TOKEN: + while (@tok) { + if ($tok[0] eq "default") { + shift(@tok); + undef $mach; # ignore 'default' lines + + next TOKEN; + } + + $tok = shift(@tok); + + if ($tok eq "machine") { + my $host = shift @tok; + $mach = { machine => $host }; + push @entries, $mach; + } + elsif (exists $options{tmap}->{$tok}) { + unless ($mach) { + log_debug("Skipping token $tok because no machine was given"); + next TOKEN; + } + + my $value = shift @tok; + unless (defined $value) { + log_debug("Token $tok had no value, skipping it."); + next TOKEN; + } + + # Following line added by rmerrell to remove '/' escape char in .netrc + $value =~ s/\/\\/\\/g; + $mach->{$tok} = $value; + } + elsif ($tok eq "macdef") { # we ignore macros + next TOKEN unless $mach; + my $value = shift @tok; + $macdef = 1; + } + } + } + + return @entries; +} + +sub read_credential_data_from_stdin { + # the query: start with every token with no value + my %q = map { $_ => undef } values(%{$options{tmap}}); + + while (<STDIN>) { + next unless m/^([^=]+)=(.+)/; + + my ($token, $value) = ($1, $2); + die "Unknown search token $token" unless exists $q{$token}; + $q{$token} = $value; + log_debug("We were given search token $token and value $value"); + } + + foreach (sort keys %q) { + log_debug("Searching for %s = %s", $_, $q{$_} || '(any value)'); + } + + return \%q; +} + +# takes the search tokens and then a list of entries +# each entry is a hash reference +sub find_netrc_entry { + my $query = shift @_; + + ENTRY: + foreach my $entry (@_) + { + my $entry_text = join ', ', map { "$_=$entry->{$_}" } keys %$entry; + foreach my $check (sort keys %$query) { + if (defined $query->{$check}) { + log_debug("compare %s [%s] to [%s] (entry: %s)", + $check, + $entry->{$check}, + $query->{$check}, + $entry_text); + unless ($query->{$check} eq $entry->{$check}) { + next ENTRY; + } + } + else { + log_debug("OK: any value satisfies check $check"); + } + } + + return $entry; + } + + # nothing was found + return; +} + +sub print_credential_data { + my $entry = shift @_; + my $query = shift @_; + + log_debug("entry has passed all the search checks"); + TOKEN: + foreach my $git_token (sort keys %$entry) { + log_debug("looking for useful token $git_token"); + # don't print unknown (to the credential helper protocol) tokens + next TOKEN unless exists $query->{$git_token}; + + # don't print things asked in the query (the entry matches them) + next TOKEN if defined $query->{$git_token}; + + log_debug("FOUND: $git_token=$entry->{$git_token}"); + printf "%s=%s\n", $git_token, $entry->{$git_token}; + } +} +sub log_verbose { + return unless $options{verbose}; + printf STDERR @_; + printf STDERR "\n"; +} + +sub log_debug { + return unless $options{debug}; + printf STDERR @_; + printf STDERR "\n"; +} -- 1.7.9.rc2 -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html