Merge branch 'ab/cvsserver'

* ab/cvsserver:
  git-cvsserver: test for pserver authentication support
  git-cvsserver: document making a password without htpasswd
  git-cvsserver: Improved error handling for pserver
  git-cvsserver: indent & clean up authdb code
  git-cvsserver: use a password file cvsserver pserver
  git-cvsserver: authentication support for pserver

3 files changed, 135 insertions, 12 deletions

diff --git a/Documentation/git-cvsserver.txt b/Documentation/git-cvsserver.txt
index dbb053ee17..c27ca4350e 100644
--- a/Documentation/git-cvsserver.txt
+++ b/Documentation/git-cvsserver.txt
@@ -72,9 +72,6 @@ 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
@@ -84,7 +81,7 @@ 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
 +
 --
@@ -101,6 +98,38 @@ 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.authdb
+setting in the config file of the repositories you want the cvsserver
+to allow writes to, for example:
+
+------
+
+   [gitcvs]
+	authdb = /etc/cvsserver/passwd
+
+------
+The format of these files is username followed by the crypted password,
+for example:
+
+------
+   myuser:$1Oyx5r9mdGZ2
+   myuser:$1$BA)@$vbnMJMDym7tA32AamXrm./
+------
+You can use the 'htpasswd' facility that comes with Apache to make these
+files, but Apache's MD5 crypt method differs from the one used by most C
+library's crypt() function, so don't use the -m option.
+
+Alternatively you can produce the password with perl's crypt() operator:
+-----
+   perl -e 'my ($user, $pass) = @ARGV; printf "%s:%s\n", $user, crypt($user, $pass)' $USER password
+-----
+
+Then provide your password via the pserver method, for example:
+------
+   cvs -d:pserver:someuser:somepassword <at> server/path/repo.git co <HEAD_name>
+------
 No special setup is needed for SSH access, other than having GIT tools
 in the PATH. If you have clients that do not accept the CVS_SERVER
 environment variable, you can rename 'git-cvsserver' to `cvs`.
diff --git a/git-cvsserver.perl b/git-cvsserver.perl
index 13751db882..3833beeef3 100755
--- a/git-cvsserver.perl
+++ b/git-cvsserver.perl
@@ -183,12 +183,58 @@ if ($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 = $line;
+
+    if ($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";
+            exit 1;
+        }
+
+        # 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] 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, "<", $authdb or die $!;
+        while (<$passwd>) {
+            if (m{^\Q$user\E:(.*)}) {
+                if (crypt($user, descramble($password)) eq $1) {
+                    $auth_ok = 1;
+                }
+            };
+        }
+        close $passwd;
+
+        unless ($auth_ok) {
+            print "I HATE YOU\n";
+            exit 1;
+        }
+
+        # 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";
@@ -1271,9 +1317,9 @@ 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";
         cleanupWorkTree();
         exit;
     }
@@ -2586,6 +2632,40 @@ sub cvs_author
     $author;
 }
 
+
+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
+    die "invalid password format $1" unless substr($str, 0, 1) eq 'A';
+
+    my @str = unpack "C*", substr($str, 1);
+    my $ret = join '', map { chr $SHIFTS[$_] } @str;
+    return $ret;
+}
+
+
 package GITCVS::log;
 
 ####
diff --git a/t/t9400-git-cvsserver-server.sh b/t/t9400-git-cvsserver-server.sh
index daef2d6c23..437e9b8112 100755
--- a/t/t9400-git-cvsserver-server.sh
+++ b/t/t9400-git-cvsserver-server.sh
@@ -48,7 +48,9 @@ test_expect_success 'setup' '
   git pull secondroot master &&
   git clone -q --bare "$WORKDIR/.git" "$SERVERDIR" >/dev/null 2>&1 &&
   GIT_DIR="$SERVERDIR" git config --bool gitcvs.enabled true &&
-  GIT_DIR="$SERVERDIR" git config gitcvs.logfile "$SERVERDIR/gitcvs.log"
+  GIT_DIR="$SERVERDIR" git config gitcvs.logfile "$SERVERDIR/gitcvs.log" &&
+  GIT_DIR="$SERVERDIR" git config gitcvs.authdb "$SERVERDIR/auth.db" &&
+  echo cvsuser:cvGVEarMLnhlA > "$SERVERDIR/auth.db"
 '
 
 # note that cvs doesn't accept absolute pathnames
@@ -94,6 +96,14 @@ git
 END VERIFICATION REQUEST
 EOF
 
+cat >login-git-ok <<EOF
+BEGIN VERIFICATION REQUEST
+$SERVERDIR
+cvsuser
+Ah<Z:yZZ30 e
+END VERIFICATION REQUEST
+EOF
+
 test_expect_success 'pserver authentication' \
   'cat request-anonymous | git-cvsserver pserver >log 2>&1 &&
    sed -ne \$p log | grep "^I LOVE YOU\$"'
@@ -107,6 +117,10 @@ test_expect_success 'pserver authentication failure (non-anonymous user)' \
    fi &&
    sed -ne \$p log | grep "^I HATE YOU\$"'
 
+test_expect_success 'pserver authentication success (non-anonymous user with password)' \
+  'cat login-git-ok | git-cvsserver pserver >log 2>&1 &&
+   sed -ne \$p log | grep "^I LOVE YOU\$"'
+
 test_expect_success 'pserver authentication (login)' \
   'cat login-anonymous | git-cvsserver pserver >log 2>&1 &&
    sed -ne \$p log | grep "^I LOVE YOU\$"'