From: avar@cpan.org (Ævar Arnfjörð Bjarmason)
To: "Martin Langhoff" <martin.langhoff@gmail.com>
Cc: "Junio C Hamano" <gitster@pobox.com>,
git@vger.kernel.org, martyn@catalyst.net.nz,
martin@catalyst.net.nz, avar@cpan.org
Subject: Re: [PATCH] Authentication support for pserver
Date: Thu, 19 Jun 2008 17:38:32 +0000 [thread overview]
Message-ID: <861w2tjpev.fsf@cpan.org> (raw)
In-Reply-To: <86iqzyse9u.fsf@cpan.org> ("Ævar Arnfjörð Bjarmason"'s message of "Fri, 07 Mar 2008 16:13:49 +0000")
avar@cpan.org (Ævar Arnfjörð Bjarmason) writes:
> avar@cpan.org (Ævar Arnfjörð Bjarmason) writes:
>
>> Better late than never, here's a more complete and hopefully final patch
>> to add authentication support to CVS. Thanks to Sam Vilain for
>> contributing and kicking me into action.
>>
>> Now you specify a user:password authentication database in the [gitcvs]
>> section. The passwords are crypt()-ed and can be produced by htpasswd,
>> example config file:
>>
>> [gitcvs]
>> enabled = 1
>> authdb = /tmp/authdb.htpasswd
>>
>> The patch can be pulled from git://git.nix.is/avar/git
>>
>> It's also produced below:
>
> The patch needed a small fix, I didn't exit(1) after an error
> condition[1]. This can also be got at git://git.nix.is/avar/git and is
> produced in full below:
>
>
> From 5900732b52c3a693bfb36c0bf56e3c5eb83ef65e Mon Sep 17 00:00:00 2001
> From: =?utf-8?q?=C3=86var=20Arnfj=C3=B6r=C3=B0=20Bjarmason?= <avar@cpan.org>
> Date: Fri, 14 Dec 2007 08:08:46 +0000
> Subject: [PATCH] git-cvsserver: authentication support for pserver
> MIME-Version: 1.0
> Content-Type: text/plain; charset=utf-8
> Content-Transfer-Encoding: 8bit
>
> Allow git-cvsserver to use authentication over pserver mode. The
> pserver user/password database is stored in the config file for each
> repository.
>
> Signed-off-by: Ævar Arnfjörð Bjarmason <avar@cpan.org>
> Worriedly-Acked-by: Martin Langhoff <martin.langhoff@gmail.com>
> ---
> Documentation/git-cvsserver.txt | 21 +++++++++--
> git-cvsserver.perl | 74 ++++++++++++++++++++++++++++++++++----
> 2 files changed, 83 insertions(+), 12 deletions(-)
>
> diff --git a/Documentation/git-cvsserver.txt b/Documentation/git-cvsserver.txt
> index d3e9993..98183d4 100644
> --- a/Documentation/git-cvsserver.txt
> +++ b/Documentation/git-cvsserver.txt
> @@ -69,9 +69,6 @@ plugin. Most functionality works fine with both of these clients.
> LIMITATIONS
> -----------
>
> -Currently cvsserver works over SSH connections for read/write clients, and
> -over pserver for anonymous CVS access.
> -
> CVS clients cannot tag, branch or perform GIT merges.
>
> git-cvsserver maps GIT branches to CVS modules. This is very different
> @@ -81,7 +78,7 @@ one or more directories.
> INSTALLATION
> ------------
>
> -1. If you are going to offer anonymous CVS access via pserver, add a line in
> +1. If you are going to offer CVS access via pserver, add a line in
> /etc/inetd.conf like
> +
> --
> @@ -98,6 +95,22 @@ looks like
> cvspserver stream tcp nowait nobody /usr/bin/git-cvsserver git-cvsserver pserver
>
> ------
> +
> +Only anonymous access is provided by pserve by default. To commit you
> +will have to create pserver accounts, simply add a [gitcvs.users]
> +section to the repositories you want to access, for example:
> +
> +------
> +
> + [gitcvs.users]
> + someuser = somepassword
> + otheruser = otherpassword
> +
> +------
> +Then provide your password via the pserver method, for example:
> +------
> + cvs -d:pserver:someuser:somepassword <at> server/path/repo.git co <HEAD_name>
> +------
> No special setup is needed for SSH access, other than having GIT tools
> in the PATH. If you have clients that do not accept the CVS_SERVER
> environment variable, you can rename git-cvsserver to cvs.
> diff --git a/git-cvsserver.perl b/git-cvsserver.perl
> index afe3d0b..9bc2ff5 100755
> --- a/git-cvsserver.perl
> +++ b/git-cvsserver.perl
> @@ -150,12 +150,35 @@ if ($state->{method} eq 'pserver') {
> exit 1;
> }
> $line = <STDIN>; chomp $line;
> - unless ($line eq 'anonymous') {
> - print "E Only anonymous user allowed via pserver\n";
> - print "I HATE YOU\n";
> - exit 1;
> + my $user = $line;
> + $line = <STDIN>; chomp $line;
> + my $password = $line;
> +
> + unless ($user eq 'anonymous') {
> + # Trying to authenticate a user
> + if (not exists $cfg->{gitcvs}->{users}) {
> + print "E the repo config file needs a [gitcvs.users] section with user/password key-value pairs\n";
> + print "I HATE YOU\n";
> + exit 1;
> + } elsif (exists $cfg->{gitcvs}->{users} and not exists $cfg->{gitcvs}->{users}->{$user}) {
> + #print "E the repo config file has a [gitcvs.users] section but the user $user is not defined in it\n";
> + print "I HATE YOU\n";
> + exit 1;
> + } else {
> + my $descrambled_password = descramble($password);
> + my $cleartext_password = $cfg->{gitcvs}->{users}->{$user};
> + if ($descrambled_password ne $cleartext_password) {
> + #print "E The password supplied for user $user was incorrect\n";
> + print "I HATE YOU\n";
> + exit 1;
> + }
> + # else fall through to LOVE
> + }
> }
> - $line = <STDIN>; chomp $line; # validate the password?
> +
> + # For checking whether the user is anonymous on commit
> + $state->{user} = $user;
> +
> $line = <STDIN>; chomp $line;
> unless ($line eq "END $request REQUEST") {
> die "E Do not understand $line -- expecting END $request REQUEST\n";
> @@ -273,7 +296,7 @@ sub req_Root
> }
> foreach my $line ( @gitvars )
> {
> - next unless ( $line =~ /^(gitcvs)\.(?:(ext|pserver)\.)?([\w-]+)=(.*)$/ );
> + next unless ( $line =~ /^(gitcvs)\.(?:(ext|pserver|users)\.)?([\w-]+)=(.*)$/ );
> unless ($2) {
> $cfg->{$1}{$3} = $4;
> } else {
> @@ -1176,9 +1199,9 @@ sub req_ci
>
> $log->info("req_ci : " . ( defined($data) ? $data : "[NULL]" ));
>
> - if ( $state->{method} eq 'pserver')
> + if ($state->{method} eq 'pserver' and $state->{user} eq 'anonymous')
> {
> - print "error 1 pserver access cannot commit\n";
> + print "error 1 anonymous user cannot commit via pserver\n";
> exit;
> }
>
> @@ -2107,6 +2130,41 @@ sub kopts_from_path
> }
> }
>
> +
> +sub descramble
> +{
> + # This table is from src/scramble.c in the CVS source
> + my @SHIFTS = (
> + 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
> + 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31,
> + 114,120, 53, 79, 96,109, 72,108, 70, 64, 76, 67,116, 74, 68, 87,
> + 111, 52, 75,119, 49, 34, 82, 81, 95, 65,112, 86,118,110,122,105,
> + 41, 57, 83, 43, 46,102, 40, 89, 38,103, 45, 50, 42,123, 91, 35,
> + 125, 55, 54, 66,124,126, 59, 47, 92, 71,115, 78, 88,107,106, 56,
> + 36,121,117,104,101,100, 69, 73, 99, 63, 94, 93, 39, 37, 61, 48,
> + 58,113, 32, 90, 44, 98, 60, 51, 33, 97, 62, 77, 84, 80, 85,223,
> + 225,216,187,166,229,189,222,188,141,249,148,200,184,136,248,190,
> + 199,170,181,204,138,232,218,183,255,234,220,247,213,203,226,193,
> + 174,172,228,252,217,201,131,230,197,211,145,238,161,179,160,212,
> + 207,221,254,173,202,146,224,151,140,196,205,130,135,133,143,246,
> + 192,159,244,239,185,168,215,144,139,165,180,157,147,186,214,176,
> + 227,231,219,169,175,156,206,198,129,164,150,210,154,177,134,127,
> + 182,128,158,208,162,132,167,209,149,241,153,251,237,236,171,195,
> + 243,233,253,240,194,250,191,155,142,137,245,235,163,242,178,152
> + );
> + my ($str) = @_;
> +
> + # This should never happen, the same password format (A) bas been
> + # used by CVS since the beginning of time
> + $str =~ s/^(.)//;
> + die "invalid password format $1" unless $1 eq 'A';
> +
> + $str =~ s/(.)/chr $SHIFTS[ord $1]/ge;
> +
> + return $str;
> +}
> +
> +
> package GITCVS::log;
>
> ####
> --
> 1.5.3.rc3.120.g68d422
>
>
> From f59c255ed14c5b80d5328f94f6934461cfe454da Mon Sep 17 00:00:00 2001
> From: Sam Vilain <sam.vilain@catalyst.net.nz>
> Date: Fri, 7 Mar 2008 11:03:14 +1300
> Subject: [PATCH] git-cvsserver: use a password file cvsserver pserver
>
> If a git repository is shared via HTTP, the config file is typically
> visible. Use an external file instead.
>
> Signed-off-by: Ævar Arnfjörð Bjarmason <avar@cpan.org>
> ---
> Documentation/git-cvsserver.txt | 21 ++++++++++++++++-----
> git-cvsserver.perl | 27 ++++++++++++++-------------
> 2 files changed, 30 insertions(+), 18 deletions(-)
>
> diff --git a/Documentation/git-cvsserver.txt b/Documentation/git-cvsserver.txt
> index 98183d4..c642f12 100644
> --- a/Documentation/git-cvsserver.txt
> +++ b/Documentation/git-cvsserver.txt
> @@ -97,16 +97,27 @@ looks like
> ------
>
> Only anonymous access is provided by pserve by default. To commit you
> -will have to create pserver accounts, simply add a [gitcvs.users]
> -section to the repositories you want to access, for example:
> +will have to create pserver accounts, simply add a gitcvs.authdb
> +setting in the config file of the repositories you want the cvsserver
> +to allow writes to, for example:
>
> ------
>
> - [gitcvs.users]
> - someuser = somepassword
> - otheruser = otherpassword
> + [gitcvs]
> + authdb = /etc/cvsserver/passwd
>
> ------
> +The format of these files is username followed by the crypted password,
> +for example:
> +
> +------
> + myuser:$1Oyx5r9mdGZ2
> + myuser:$1$BA)@$vbnMJMDym7tA32AamXrm./
> +------
> +You can use the 'htpasswd' facility that comes with Apache to make these
> +files, but Apache's MD5 crypt method differs from the one used by most C
> +library's crypt() function, so don't use the -m option.
> +
> Then provide your password via the pserver method, for example:
> ------
> cvs -d:pserver:someuser:somepassword <at> server/path/repo.git co <HEAD_name>
> diff --git a/git-cvsserver.perl b/git-cvsserver.perl
> index 9bc2ff5..e54cbcd 100755
> --- a/git-cvsserver.perl
> +++ b/git-cvsserver.perl
> @@ -156,24 +156,25 @@ if ($state->{method} eq 'pserver') {
>
> unless ($user eq 'anonymous') {
> # Trying to authenticate a user
> - if (not exists $cfg->{gitcvs}->{users}) {
> - print "E the repo config file needs a [gitcvs.users] section with user/password key-value pairs\n";
> + if (not exists $cfg->{gitcvs}->{authdb}) {
> + print "E the repo config file needs a [gitcvs.authdb] section with a filename\n";
> print "I HATE YOU\n";
> exit 1;
> - } elsif (exists $cfg->{gitcvs}->{users} and not exists $cfg->{gitcvs}->{users}->{$user}) {
> - #print "E the repo config file has a [gitcvs.users] section but the user $user is not defined in it\n";
> + }
> + my $auth_ok;
> + open PASSWD, "<$cfg->{gitcvs}->{authdb}" or die $!;
> + while(<PASSWD>) {
> + if (m{^\Q$user\E:(.*)}) {
> + if (crypt($user, $1) eq $1) {
> + $auth_ok = 1;
> + }
> + };
> + }
> + unless ($auth_ok) {
> print "I HATE YOU\n";
> exit 1;
> - } else {
> - my $descrambled_password = descramble($password);
> - my $cleartext_password = $cfg->{gitcvs}->{users}->{$user};
> - if ($descrambled_password ne $cleartext_password) {
> - #print "E The password supplied for user $user was incorrect\n";
> - print "I HATE YOU\n";
> - exit 1;
> - }
> - # else fall through to LOVE
> }
> + # else fall through to LOVE
> }
>
> # For checking whether the user is anonymous on commit
> --
> 1.5.3.rc3.120.g68d422
>
>
> From e8b69f313888900447f45ac3a8dceb38bd5c261e Mon Sep 17 00:00:00 2001
> From: =?utf-8?q?=C3=86var=20Arnfj=C3=B6r=C3=B0=20Bjarmason?= <avar@cpan.org>
> Date: Thu, 6 Mar 2008 23:43:13 +0000
> Subject: [PATCH] Indent the last commit to fit with the rest of the code.
>
> Use lexical filehandles instead of global globs
>
> Close the filehandle after the password database has been read
>
> Signed-off-by: Ævar Arnfjörð Bjarmason <avar@cpan.org>
> ---
> git-cvsserver.perl | 23 +++++++++++++----------
> 1 files changed, 13 insertions(+), 10 deletions(-)
>
> diff --git a/git-cvsserver.perl b/git-cvsserver.perl
> index e54cbcd..f956ac9 100755
> --- a/git-cvsserver.perl
> +++ b/git-cvsserver.perl
> @@ -161,16 +161,19 @@ if ($state->{method} eq 'pserver') {
> print "I HATE YOU\n";
> exit 1;
> }
> - my $auth_ok;
> - open PASSWD, "<$cfg->{gitcvs}->{authdb}" or die $!;
> - while(<PASSWD>) {
> - if (m{^\Q$user\E:(.*)}) {
> - if (crypt($user, $1) eq $1) {
> - $auth_ok = 1;
> - }
> - };
> - }
> - unless ($auth_ok) {
> +
> + my $auth_ok;
> + open my $passwd, "<", $cfg->{gitcvs}->{authdb} or die $!;
> + while (<$passwd>) {
> + if (m{^\Q$user\E:(.*)}) {
> + if (crypt($user, $1) eq $1) {
> + $auth_ok = 1;
> + }
> + };
> + }
> + close $passwd;
> +
> + unless ($auth_ok) {
> print "I HATE YOU\n";
> exit 1;
> }
> --
> 1.5.3.rc3.120.g68d422
>
>
> From 90d3468556b46fc649a9408af42ff24ed2e50455 Mon Sep 17 00:00:00 2001
> From: =?utf-8?q?=C3=86var=20Arnfj=C3=B6r=C3=B0=20Bjarmason?= <avar@cpan.org>
> Date: Fri, 7 Mar 2008 00:06:52 +0000
> Subject: [PATCH] Produce an error if the user tries to supply a password for anonymous
>
> Clarify the error message produced when there's no [gitcvs.authdb]
>
> Produce an E error if the authdb doesn't exist instead of spewing $!
> to the user
>
> do crypt($user, descramble($pass)) eq $hash; crypt($user, $hash) eq
> $hash would accept any password
>
> Signed-off-by: Ævar Arnfjörð Bjarmason <avar@cpan.org>
> ---
> git-cvsserver.perl | 28 +++++++++++++++++++++++-----
> 1 files changed, 23 insertions(+), 5 deletions(-)
>
> diff --git a/git-cvsserver.perl b/git-cvsserver.perl
> index f956ac9..aa0299e 100755
> --- a/git-cvsserver.perl
> +++ b/git-cvsserver.perl
> @@ -154,19 +154,36 @@ if ($state->{method} eq 'pserver') {
> $line = <STDIN>; chomp $line;
> my $password = $line;
>
> - unless ($user eq 'anonymous') {
> + if ($user eq 'anonymous') {
> + # "A" will be 1 byte, use length instead in case the
> + # encryption method ever changes (yeah, right!)
> + if (length($password) > 1 ) {
> + print "E Don't supply a password for the `anonymous' user\n";
> + print "I HATE YOU\n";
> + }
> +
> + # Fall through to LOVE
> + } else {
> # Trying to authenticate a user
> if (not exists $cfg->{gitcvs}->{authdb}) {
> - print "E the repo config file needs a [gitcvs.authdb] section with a filename\n";
> + print "E the repo config file needs a [gitcvs] section with an 'authdb' parameter set to the filename of the authentication database\n";
> + print "I HATE YOU\n";
> + exit 1;
> + }
> +
> + my $authdb = $cfg->{gitcvs}->{authdb};
> +
> + unless (-e $authdb) {
> + print "E The authentication database specified in [gitcvs.authdb] does not exist\n";
> print "I HATE YOU\n";
> exit 1;
> }
>
> my $auth_ok;
> - open my $passwd, "<", $cfg->{gitcvs}->{authdb} or die $!;
> + open my $passwd, "<", $authdb or die $!;
> while (<$passwd>) {
> if (m{^\Q$user\E:(.*)}) {
> - if (crypt($user, $1) eq $1) {
> + if (crypt($user, descramble($password)) eq $1) {
> $auth_ok = 1;
> }
> };
> @@ -177,7 +194,8 @@ if ($state->{method} eq 'pserver') {
> print "I HATE YOU\n";
> exit 1;
> }
> - # else fall through to LOVE
> +
> + # Fall through to LOVE
> }
>
> # For checking whether the user is anonymous on commit
> --
> 1.5.3.rc3.120.g68d422
>
>
> From a55dfa2667da1473199ee70ca6cfd53094001119 Mon Sep 17 00:00:00 2001
> From: =?utf-8?q?=C3=86var=20Arnfj=C3=B6r=C3=B0=20Bjarmason?= <avar@cpan.org>
> Date: Fri, 7 Mar 2008 00:09:14 +0000
> Subject: [PATCH] document a perl snippet to produce passwords for those that don't have htpasswd
>
>
> Signed-off-by: Ævar Arnfjörð Bjarmason <avar@cpan.org>
> ---
> Documentation/git-cvsserver.txt | 5 +++++
> 1 files changed, 5 insertions(+), 0 deletions(-)
>
> diff --git a/Documentation/git-cvsserver.txt b/Documentation/git-cvsserver.txt
> index c642f12..d410a11 100644
> --- a/Documentation/git-cvsserver.txt
> +++ b/Documentation/git-cvsserver.txt
> @@ -118,6 +118,11 @@ You can use the 'htpasswd' facility that comes with Apache to make these
> files, but Apache's MD5 crypt method differs from the one used by most C
> library's crypt() function, so don't use the -m option.
>
> +Alternatively you can produce the password with perl's crypt() operator:
> +-----
> + perl -e 'my ($user, $pass) = @ARGV; printf "%s:%s\n", $user, crypt($user, $pass)' $USER password
> +-----
> +
> Then provide your password via the pserver method, for example:
> ------
> cvs -d:pserver:someuser:somepassword <at> server/path/repo.git co <HEAD_name>
> --
> 1.5.3.rc3.120.g68d422
>
>
> From 60f893bd9fe329bd5cf8ec513d10ec00e85feb2c Mon Sep 17 00:00:00 2001
> From: =?utf-8?q?=C3=86var=20Arnfj=C3=B6r=C3=B0=20Bjarmason?= <avar@cpan.org>
> Date: Fri, 7 Mar 2008 16:06:31 +0000
> Subject: [PATCH] exit after producing the error about anonymous having a password
>
>
> Signed-off-by: Ævar Arnfjörð Bjarmason <avar@cpan.org>
> ---
> git-cvsserver.perl | 1 +
> 1 files changed, 1 insertions(+), 0 deletions(-)
>
> diff --git a/git-cvsserver.perl b/git-cvsserver.perl
> index aa0299e..da48ebd 100755
> --- a/git-cvsserver.perl
> +++ b/git-cvsserver.perl
> @@ -160,6 +160,7 @@ if ($state->{method} eq 'pserver') {
> if (length($password) > 1 ) {
> print "E Don't supply a password for the `anonymous' user\n";
> print "I HATE YOU\n";
> + exit 1;
> }
>
> # Fall through to LOVE
> --
> 1.5.3.rc3.120.g68d422
>
>
>
> 1. http://git.nix.is/?p=avar/git;a=commitdiff;h=60f893bd9fe329bd5cf8ec513d10ec00e85feb2c
It has been over 3 months since I submitted this patch without anyone
acting on it. In absence of comment from the Mart[yi]ns could this
please applied anyway?
next prev parent reply other threads:[~2008-06-19 18:08 UTC|newest]
Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-12-14 4:08 [PATCH] Authentication support for pserver Ævar Arnfjörð Bjarmason
2007-12-14 5:32 ` Junio C Hamano
2007-12-14 5:44 ` Shawn O. Pearce
2007-12-14 6:55 ` Ævar Arnfjörð Bjarmason
2007-12-14 8:13 ` Junio C Hamano
2007-12-14 21:08 ` Ævar Arnfjörð Bjarmason
2007-12-18 9:41 ` Martin Langhoff
2007-12-18 20:39 ` Martin Langhoff
[not found] ` <46a038f90712181238p7529a02bmde21c89956a3f641@mail.gmail.com>
2007-12-18 21:10 ` Ævar Arnfjörð Bjarmason
2007-12-18 21:37 ` Junio C Hamano
2008-03-07 0:48 ` Ævar Arnfjörð Bjarmason
2008-03-07 16:13 ` Ævar Arnfjörð Bjarmason
2008-06-19 17:38 ` Ævar Arnfjörð Bjarmason [this message]
2008-06-19 19:00 ` Martin Langhoff
2008-06-19 19:21 ` Junio C Hamano
2008-06-19 20:14 ` Junio C Hamano
2010-05-15 2:45 ` [PATCH 0/6] git-cvsserver: password " Ævar Arnfjörð Bjarmason
2010-05-15 2:45 ` [PATCH 1/6] git-cvsserver: authentication " Ævar Arnfjörð Bjarmason
2010-05-15 15:06 ` [PATCH 1/6 v2] " Ævar Arnfjörð Bjarmason
2010-05-15 2:46 ` [PATCH 2/6] git-cvsserver: use a password file cvsserver pserver Ævar Arnfjörð Bjarmason
2010-05-15 15:07 ` [PATCH 2/6 v2] " Ævar Arnfjörð Bjarmason
2010-05-15 2:46 ` [PATCH 3/6] git-cvsserver: indent & clean up authdb code Ævar Arnfjörð Bjarmason
2010-05-15 2:46 ` [PATCH 4/6] git-cvsserver: Improved error handling for pserver Ævar Arnfjörð Bjarmason
2010-05-15 2:46 ` [PATCH 5/6] git-cvsserver: document making a password without htpasswd Ævar Arnfjörð Bjarmason
2010-05-15 2:46 ` [PATCH 6/6] git-cvsserver: test for pserver authentication support Ævar Arnfjörð Bjarmason
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