This patch contains:
* checks for malloc return value + treat callers;
* modified malloc() + ZeroMemory() to calloc();
* misc fixes of micro errors seen during the code audit:
** some invalid checks in gcc.c, also there were some possible
integer overflow. This is interesting because at the end the data are parsed
and freed directly, so it's a vulnerability in some kind of dead code (at least
useless);
** fixed usage of GetComputerNameExA with just one call, when 2 were used
in misc places. According to MSDN GetComputerNameA() is supposed to return
an error when called with NULL;
** there were a bug in the command line parsing of shadow;
** in freerdp_dynamic_channel_collection_add() the size of array was multiplied
by 4 instead of 2 on resize
Small cleanup of passing around decorations flag.
Limit PercentScreen to single monitor vs. entire desktop. IMO - this is better behavior in a multimonitor environment.
Handle fullscreen windows better:
1. Ensure that size hints are set to allow resizing before setting a window to fullscreen as some window managers do not behave properly.
2. Handle fullscreen toggles without destroying and recreating window.
3. Use NET_WM_STATE_FULLSCREEN Extended Window Manager Hint for fullscreen functionality
4. Use the NET_WM_FULLSCREEN_MONITORS Extended Window Manager Hint when appropriate
5. When a single monitor fullscreen is requested - use the current monitor(as determined from mouse location)
6. Handle cases where there is no local monitor at coordinate 0,0. The Windows server expect there to be a monitor at this location, so we maintain offset if necessary between our local primary monitor and the server side primary monitor located at 0,0.
[MS-RDPBCGR] Section 5.3 describes the encryption level and method values for
standard RDP security.
Looking at the current usage of these values in the FreeRDP code gives me
reason to believe that there is a certain lack of understanding of how these
values should be handled.
The encryption level is only configured on the server side in the "Encryption
Level" setting found in the Remote Desktop Session Host Configuration RDP-Tcp
properties dialog and this value is never transferred from the client to the
server over the wire.
The possible options are "None", "Low", "Client Compatible", "High" and
"FIPS Compliant". The client receices this value in the Server Security Data
block (TS_UD_SC_SEC1), probably only for informational purposes and maybe to
give the client the possibility to verify if the server's decision for the
encryption method confirms to the server's encryption level.
The possible encryption methods are "NONE", "40BIT", "56BIT", "128BIT" and
"FIPS" and the RDP client advertises the ones it supports to the server in the
Client Security Data block (TS_UD_CS_SEC).
The server's configured encryption level value restricts the possible final
encryption method.
Something that I was not able to find in the documentation is the priority
level of the individual encryption methods based on which the server makes its
final method decision if there are several options.
My analysis with Windows Servers reveiled that the order is 128, 56, 40, FIPS.
The server only chooses FIPS if the level is "FIPS Comliant" or if it is the
only method advertised by the client.
Bottom line:
* FreeRDP's client side does not need to set settings->EncryptionLevel
(which was done quite frequently).
* FreeRDP's server side does not have to set the supported encryption methods
list in settings->EncryptionMethods
Changes in this commit:
Removed unnecessary/confusing changes of EncryptionLevel/Methods settings
Refactor settings->DisableEncryption
* This value actually means "Advanced RDP Encryption (NLA/TLS) is NOT used"
* The old name caused lots of confusion among developers
* Renamed it to "UseRdpSecurityLayer" (the compare logic stays untouched)
Any client's setting of settings->EncryptionMethods were annihilated
* All clients "want" to set all supported methods
* Some clients forgot 56bit because 56bit was not supported at the time the
code was written
* settings->EncryptionMethods was overwritten anyways in nego_connect()
* Removed all client side settings of settings->EncryptionMethods
The default is "None" (0)
* Changed nego_connect() to advertise all supported methods if
settings->EncryptionMethods is 0 (None)
* Added a commandline option /encryption-methods:comma separated list of the
values "40", "56", "128", "FIPS". E.g. /encryption-methods:56,128
* Print warning if server chooses non-advertised method
Verify received level and method in client's gcc_read_server_security_data
* Only accept valid/known encryption methods
* Verify encryption level/method combinations according to MS-RDPBCGR 5.3.2
Server implementations can now set settings->EncryptionLevel
* The default for settings->EncryptionLevel is 0 (None)
* nego_send_negotiation_response() changes it to ClientCompatible in that case
* default to ClientCompatible if the server implementation set an invalid level
Fix server's gcc_write_server_security_data
* Verify server encryption level value set by server implementations
* Choose rdp encryption method based on level and supported client methods
* Moved FIPS to the lowest priority (only used if other methods are possible)
Updated sample server
* Support RDP Security (RdpKeyFile was not set)
* Added commented sample code for setting the security level
This adds 2 arguments:
/tls-ciphers List of permitted openssl ciphers - see ciphers(1)
/tls-ciphers-netmon Use tls ciphers that netmon can parse
With KB2919355, client/server negotiate the use of
TLS cipher TLS_ECDHE_RSA_WITH_AES_256_CBC_SHA,
which works fine except that netmon can't parse it.
By adding commandline /tls-ciphers-netmon, we restrict
the available ciphers to a list that netmon can
deal with. Also adds /tls-ciphers, which
accepts a string arg, for further customization.
# By Marc-André Moreau (20) and others
# Via Mike McDonald (6) and others
* 'master' of git://github.com/awakecoding/FreeRDP: (26 commits)
libfreerdp-codec: fix C++ headers
libfreerdp-codec: fix ClearCodec short vbar cache hit
libfreerdp-codec: improve ClearCodec error checking
libfreerdp-codec: fix ClearCodec RLEX decoding
libfreerdp-codec: ClearCodec fix error codes and wrapping around of cursors
libfreerdp-codec: fix some ClearCodec flag checking
Fixed issue with last merge.
Added #ifdef WITH_OPENH264 ... #endif to appropriate places in the code.
libfreerdp-codec: handle long vbar length mismatch
channels/rdpgfx: add egfx command line options and settings
libfreerdp-codec: reduce number of variables
libfreerdp-codec: improve ClearCodec robustness
libfreerdp-codec: simplify ClearCodec code
Initial implementation of H.264 decoder for MS-RDPEGFX
libfreerdp-codec: improve ClearCodec subcodec xStart, yStart handling
libfreerdp-codec: improve ClearCodec subcodec support
libfreerdp-codec: improve ClearCodec error checking
libfreerdp-codec: more ClearCodec vBar caching
channels/rdpgfx: harden parsing code
libfreerdp-codec: add ClearCodec glyph cache
...
This big patch allows to have non-blocking writes. To achieve
this, it slightly changes the way transport is handled. The misc transport
layers are handled with OpenSSL BIOs. In the chain we insert a
bufferedBIO that will bufferize write calls that couldn't be honored.
For an access with Tls security the BIO chain would look like this:
FreeRdp Code ===> SSL bio ===> buffered BIO ===> socket BIO
The buffered BIO will store bytes that couldn't be send because of
blocking write calls.
This patch also rework TSG so that it would look like this in the
case of SSL security with TSG:
(TSG in)
> SSL BIO => buffered BIO ==> socket BIO
/
FreeRdp => SSL BIO => TSG BIO
\
> SSL BIO => buffered BIO ==> socket BIO
(TSG out)
So from the FreeRDP point of view sending something is only BIO_writing
on the frontBio (last BIO on the left).
