Fix symbolic link length reporting (allows git to work with symbolic links)

Fix password handling in --stdinpass option


git-svn-id: http://encfs.googlecode.com/svn/trunk@4 db9cf616-1c43-0410-9cb8-a902689de0d6

configure.ac

@@ -1,7 +1,7 @@
 dnl Process this file with autoconf to produce a configure script.
 
 AC_INIT(encfs/encfs.h) dnl a source file from your sub dir
-AM_INIT_AUTOMAKE(encfs, 1.4.0) dnl searches for some needed programs
+AM_INIT_AUTOMAKE(encfs, 1.4.1) dnl searches for some needed programs
 
 dnl without this order in this file, automake will be confused!
 dnl

encfs/FileUtils.cpp

@@ -63,6 +63,10 @@ using namespace std;
 using namespace gnu;
 
 static const int DefaultBlockSize = 512;
+// The maximum length of text passwords.  If longer are needed,
+// use the extpass option, as extpass can return arbitrary length binary data.
+static const int MaxPassBuf = 512;
+
 // environment variable names for values encfs stores in the environment when
 // calling an external password program.
 static const char ENCFS_ENV_ROOTDIR[] = "encfs_root";
@@ -1146,13 +1150,15 @@ void showFSInfo( const EncFSConfig &config )
     
 CipherKey getUserKey( const shared_ptr<Cipher> &cipher, bool useStdin )
 {
-    const int MaxPassBuf = 1024;
     char passBuf[MaxPassBuf];
     char *res;
 
     if( useStdin )
     {
 	res = fgets( passBuf, sizeof(passBuf), stdin );
+	// Kill the trailing newline.
+	if(passBuf[ strlen(passBuf)-1 ] == '\n')
+	    passBuf[ strlen(passBuf)-1 ] = '\0';
     } else
     {
 	// xgroup(common)
@@ -1173,7 +1179,7 @@ CipherKey getUserKey( const shared_ptr<Cipher> &cipher, bool useStdin )
 
 std::string readPassword( int FD )
 {
-    char buffer[2048];
+    char buffer[1024];
     string result;
 
     while(1)
@@ -1279,7 +1285,6 @@ CipherKey getUserKey( const std::string &passProg,
 
 CipherKey getNewUserKey( const shared_ptr<Cipher> &cipher )
 {
-    const int MaxPassBuf = 64;
     CipherKey userKey;
     char passBuf[MaxPassBuf];
     char passBuf2[MaxPassBuf];

encfs/MemoryPool.cpp

@@ -34,41 +34,33 @@
 
 using namespace rlog;
 
-#if HAVE_SSL
-
 # include <openssl/buffer.h>
 #define BLOCKDATA( BLOCK ) (unsigned char*)BLOCK->data->data
 
-#endif
-
 
 struct BlockList
 {
     BlockList *next;
     int size;
-#ifdef HAVE_SSL
     BUF_MEM *data;
-#endif
 };
 
 static BlockList *allocBlock( int size )
 {
     BlockList *block = new BlockList;
     block->size = size;
-#ifdef HAVE_SSL
     block->data = BUF_MEM_new( );
     BUF_MEM_grow( block->data, size );
     VALGRIND_MAKE_MEM_NOACCESS( block->data->data, block->data->max );
-#endif
+
     return block;
 }
 
 static void freeBlock( BlockList *el )
 {
-#ifdef HAVE_SSL
     VALGRIND_MAKE_MEM_UNDEFINED( el->data->data, el->data->max );
     BUF_MEM_free( el->data );
-#endif
+    
     delete el;
 }
 

encfs/encfs.cpp

@@ -48,6 +48,7 @@ extern "C" {
 #include <map>
 
 #include <boost/tuple/tuple.hpp>
+#include <boost/scoped_array.hpp>
 
 #include "DirNode.h"
 #include "MemoryPool.h"
@@ -161,7 +162,28 @@ static int withFileNode( const char *opName,
 
 int _do_getattr(FileNode *fnode, struct stat *stbuf)
 {
-    return fnode->getAttr(stbuf);
+    int res = fnode->getAttr(stbuf);
+    if(res == ESUCCESS && S_ISLNK(stbuf->st_mode))
+    {
+	EncFS_Context *ctx = context();
+	shared_ptr<DirNode> FSRoot = ctx->getRoot(&res);
+	if(FSRoot)
+	{
+	    // determine plaintext link size..  Easiest to read and decrypt..
+	    scoped_array<char> buf(new char[stbuf->st_size+1]);
+
+	    res = ::readlink( fnode->cipherName(), buf.get(), stbuf->st_size );
+	    // other functions expect c-strings to be null-terminated, which
+	    // readlink doesn't provide
+	    buf[res] = '\0';
+
+	    stbuf->st_size = FSRoot->plainPath( buf.get() ).length();
+
+	    res = ESUCCESS;
+	}
+    }
+
+    return res;
 }
 
 int encfs_getattr(const char *path, struct stat *stbuf)
@@ -339,7 +361,6 @@ int encfs_rmdir(const char *path)
     return withCipherPath( "rmdir", path, _do_rmdir, 0 );
 }
 
-
 int _do_readlink(EncFS_Context *ctx, const string &cyName,
 	tuple<char *, size_t> data )
 {

encfs/encfs.pod

@@ -1,10 +1,10 @@
 =cut
-Copyright (c) 2003-2004, Valient Gough <vgough@pobox.com>
+Copyright (c) 2003-2008, Valient Gough <vgough@pobox.com>
 All rights reserved.
 
 EncFS is free software; you can distribute it and/or modify it under the terms
 of the GNU General Public License (GPL), as published by the Free Software
-Foundation; either version 2 of the License, or (at your option) any later
+Foundation; either version 3 of the License, or (at your option) any later
 version.
 
 =pod
@@ -19,17 +19,18 @@ B<encfs> [B<--version>] [B<-s>] [B<-f>] [B<-v>|B<--verbose>]
 [B<-i MINUTES>|B<--idle=MINUTES>] [B<--extpass=program>] 
 [B<-S>|B<--stdinpass>] [B<--anykey>] [B<--forcedecode>] 
 [B<-d>|B<--fuse-debug>] [B<--public>] [B<--no-default-flags>]
+[B<--ondemand>] [B<--reverse>] [B<-o FUSE_OPTION>]
 I<rootdir> I<mountPoint> 
 [B<--> [I<Fuse Mount Options>]]
 
 =head1 DESCRIPTION
 
-B<encfs> creates a virtual encrypted filesystem which stores encrypted data in
+B<EncFS> creates a virtual encrypted filesystem which stores encrypted data in
 the I<rootdir> directory and makes the unencrypted data visible at the
 I<mountPoint> directory.  The user must supply a password which is used to
 (indirectly) encrypt both filenames and file contents.
 
-If B<encfs> is unable to find a supported filesystem at the specified
+If B<EncFS> is unable to find a supported filesystem at the specified
 I<rootdir>, then the user will be asked if they wish to create a new encrypted
 filesystem at the specified location.  Options will be presented to the user
 allowing some control over the algorithms to use.  As B<EncFS> matures, there
@@ -49,8 +50,8 @@ However simply having files open does not count as activity.
 
 =item B<-f>
 
-The B<-f> (I<foreground>) option causes B<encfs> to run in the foreground.
+The B<-f> (I<foreground>) option causes B<EncFS> to run in the foreground.
-Normally B<encfs> spawns off as a daemon and runs in the background, returning
+Normally B<EncFS> spawns off as a daemon and runs in the background, returning
 control to the spawning shell.  With the B<-f> option, it will run in the
 foreground and any warning/debug log messages will be displayed on standard
 error.  In the default (background) mode, all log messages are logged via
@@ -58,25 +59,25 @@ syslog.
 
 =item B<-v>, B<--verbose>
 
-Causes B<encfs> to enable logging of various debug channels within B<encfs>.
+Causes B<EncFS> to enable logging of various debug channels within B<EncFS>.
 Normally these logging messages are disabled and have no effect.  It is
 recommended that you run in foreground (B<-f>) mode when running with verbose
 enabled.
 
 =item B<-s>
 
-The B<-s> (I<single threaded>) option causes B<encfs> to run in single threaded
+The B<-s> (I<single threaded>) option causes B<EncFS> to run in single threaded
-mode.  By default, B<encfs> runs in multi-threaded mode.  This option is used
+mode.  By default, B<EncFS> runs in multi-threaded mode.  This option is used
-during B<encfs> development in order to simplify debugging and allow it to run
+during B<EncFS> development in order to simplify debugging and allow it to run
 under memory checking tools..
 
 =item B<-d>, B<--fuse-debug>
 
 Enables debugging within the B<FUSE> library.  This should only be used if you
-suspect a problem within B<FUSE> itself (not B<encfs>), as it generates a lot
+suspect a problem within B<FUSE> itself (not B<EncFS>), as it generates a lot
 of low-level data and is not likely to be very helpful in general problem
 tracking.  Try I<verbose> mode (B<-v>) first, which gives a higher level view
-of what is happening within B<encfs>.
+of what is happening within B<EncFS>.
 
 =item B<--forcedecode>
 
@@ -104,9 +105,59 @@ it will not have the ability to change ownership of files.  I recommend that
 you instead investigate if the fuse allow_other option can be used to do what
 you want before considering the use of B<--public>.
 
+=item B<--ondemand>
+
+Mount the filesystem on-demand.  This currently only makes sense in combination
+with B<--idle> and B<--extpass> options.  When the filesystem becomes idle,
+instead of exiting, B<EncFS> stops allowing access to the filesystem by
+internally dropping it's reference to it.  If someone attempts to access the
+filesystem again, the extpass program is used to prompt the user for the
+password.  If this succeeds, then the filesystem becomes available again.
+
+=item B<--reverse>
+
+Normally B<EncFS> provides a plaintext view of data on demand.  Normally it
+stores enciphered data and displays plaintext data.  With B<--reverse> it takes
+as source plaintext data and produces enciphered data on-demand.  This can be
+useful for creating remote encrypted backups, where you do not wish to keep the
+local files unencrypted.
+
+For example, the following would create an encrypted view in /tmp/crypt-view.
+
+    encfs --reverse /home/me /tmp/crypt-view
+
+You could then copy the /tmp/crypt-view directory in order to have a copy of
+the encrypted data.  You must also keep a copy of the file /home/me/.encfs5
+which contains the filesystem information.  Together, the two can be used to
+reproduce the unencrypted data:
+
+    ENCFS5_CONFIG=/home/me/.encfs5 encfs /tmp/crypt-view /tmp/plain-view
+
+Now /tmp/plain-view contains the same data as /home/me
+
+Note that B<--reverse> mode only works with limited configuration options, so
+many settings may be disabled when used.
+
+=item B<-o FUSE_ARG>
+
+Pass through B<FUSE> args to the underlying library.  This makes it easy to
+pass FUSE options when mounting B<EncFS> via mount (and /etc/fstab).  Eg:
+
+    mount encfs#/home/me-crypt /home/me -t fuse -o kernel_cache
+
+Note that encfs arguments cannot be set this way.  If you need to set encfs
+arguments, create a wrapper, such as  encfs-reverse;
+
+    #!/bin/sh
+    encfs --reverse $*
+
+Then mount using the script path
+
+    mount encfs-reverse#/home/me /home/me-crypt -t fuse
+
 =item B<-->
 
-The B<--> option tells B<encfs> to send any remaining arguments directly to
+The B<--> option tells B<EncFS> to send any remaining arguments directly to
 B<FUSE>.  In turn, B<FUSE> passes the arguments to B<fusermount>.  See
 the B<fusermount> help page for information on available commands.
 
@@ -135,6 +186,10 @@ for a trailing newline (\n) which will be removed.
 For example, specifying B<--extpass>=I</usr/lib/ssh/ssh-askpass> will cause
 B<EncFS> to use ssh's password prompt program.  
 
+B<Note>: B<EncFS> reads at most 2k of data from the password program, and it
+removes any trailing newline.  Versions before 1.4.x accepted only 64 bytes of
+text.
+
 =item B<-S>, B<--stdinpass>
 
 Read password from standard input, without prompting.  This may be useful for
@@ -452,7 +507,7 @@ Per-File Initialization Vector support prevents this.
 This library is distributed in the hope that it will be useful, but WITHOUT ANY
 WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
 PARTICULAR PURPOSE.  Please refer to the "COPYING" file distributed with
-B<encfs> for complete details.
+B<EncFS> for complete details.
 
 =head1 AUTHORS