The dynamic channel handler in xrdp_channel.c is updated to allow
the procs `data_first` pointer to be NULL. If this is done, the
channel handler performs all the dechunking necessary for the channel,
and only complete data PDUs are passed to procs 'data' callback.
This facility is applied to the dynamic channels supported by xrdp_mm.c.
The incoming callbacks for these channels now provide complete support
for the specification in [MS-RDPEDYC]. The existing channels were
incomplete in these respects:
1) The "Microsoft::Windows::RDS::Graphics" channel handler did not
support incoming PDUs between 1591 and 1600 bytes. The specification
calls for these to be sent as a single DATA_FIRST PDU.
2) The "Microsoft::Windows::RDS::DisplayControl" channel handler did
not support incoming PDUs over 1590 bytes.
- add addr_is_ipv4 helper function
- add addr_is_ipv6 helper function
- add get_socket_family helper function
- g_tcp_connect:
- #define for MAX_PORT_STR length
- create *addr_arg char that is used in getaddrinfo so we can do any last-minute changes directly
- add chars host and service which are primarily used for debug logging of attempted connection points
- calls get_socket_family to discover family of socket
- add switch case logic for AF_INET6/4:
- v4: just calls addr_is_ipv6 so we don't fail on a hostname input
- v6: drop addrconfig flag and add AI_ALL so we can try to map ipv4 destinations against ipv6 socket to support varied configurations we could see
- if an ipv4 address comes in against an ipv6 socket, we map it to try and connect anyways
- getaddrinfo now calls addr_arg so it picks up changes that an ipv6-case may have done
- before calling connect, use getnameinfo to get logging values for the actual host ip/port we are about to attempt a connect on - I found this useful when debugging so thought it had value to keep
- change if (res > -1) to if (res == 0): the bsd man pages for getaddrinfo only promise that it returns 0 on success, so it seems sensible to me to cover the event that an error code could be positive, which freebsd has some positive EAI_* errors based on this: https://github.com/freebsd/freebsd-src/blob/main/lib/libc/net/gai_strerror.c
- remove connect_loopback entirely: this had several bits of logic handling ipv6 and ipv4 mixing already and ended up being redundant because of the restructuring of g_tcp_connect, which covers direct ip address char* inputs now
- add comment about OSX to IPv6 function for clarity
As far as possible, use of the X11 display number is kept to
X11-specific routines. This is to make it easier to restructure
the code to add non-X11 display support.
On MacOS, stdint.h is provided by the compiler for C, and by
the SDK for C++.
OSX 14.4 appears to define char16_t and char32_t within stdint.h for
C++. Defining them again results in:
```
../common/arch.h:53:24: error: cannot combine with previous 'type-name' declaration specifier
typedef uint_least16_t char16_t;
^
../common/arch.h:53:1: warning: typedef requires a name [-Wmissing-declarations]
typedef uint_least16_t char16_t;
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
../common/arch.h:54:24: error: cannot combine with previous 'type-name' declaration specifier
typedef uint_least32_t char32_t;
^
../common/arch.h:54:1: warning: typedef requires a name [-Wmissing-declarations]
typedef uint_least32_t char32_t;
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
```
This commit addresses these kind of errors:
portability: Passing NULL after the last typed argument to a variadic function leads to undefined behaviour. [varFuncNullUB]
Reason is that C does not guarantee that all pointer types are the same
size. See C99 6.2.5(27). cppcheck requires some sort of cast when NULL
is used as the last argument in a variadic list.
the N policy in sesman.ini, allowing xrdp sessions to be tagged with an
instance name to enable persistent association with a specific
xrdp instance, to allow experiences where users reconnect to specific
sessions based on e.g. the xrdp listening port used.
Functions are added to xrdpapi to allows the connection status
to be determimed. These functions are modelled on the Windows API
functions, but are not compatible with them. In particular, the error
handling is different.
A way for an application to receive events is also provided. At present,
only connect/disconnected events are implemented.
```
/home/user/CLionProjects/xrdp/common/list.c: In function ‘list_create_sized’:
/home/user/CLionProjects/xrdp/common/list.c:50:41: error: ‘calloc’ sizes specified with ‘sizeof’ in the earlier argument and not in the later argument [-Werror=calloc-transposed-args]
50 | self = (struct list *)calloc(sizeof(struct list), 1);
| ^~~~~~
/home/user/CLionProjects/xrdp/common/list.c:50:41: note: earlier argument should specify number of elements, later size of each element
```
Coverity scan picked up on the result on g_chmod_hex() not being
checked. This call has now been moved to the place where the file is
checked for writeability, as we only really need to make it when the
file is created.
This name better matches the name from [MS-RDPBCGR]. Also, the size
of the UTF-8 buffer allocated for the client name is not large
enough for some of the names which could potentially be passed across
in UTF-16 from the client.
This allows sesexec to send a reason for a connection close
request to xrdp.
xrdp is also updated to support server initiated disconnection sequences
from [MS-RDPBCGR] 1.3.1.4, along with reporting a reason to the client
for the disconnection.
This type can be used to store sets of integers. It is intended to
be used to keep track of the display numbers allocated to sessions and
SCP connections.
A test suite for the new type is also added.
The data in 'struct xrdp_client_info' which is shared with xorgxrdp
is separated out into a separate structure. This makes it simpler to
change 'struct xrdp_client_info' without affecting xorgxrdp.
1) In FIPS mode, Classic RDP security is not allowed at all.
2) In FIPS mode xrdp-keygen creates an empty file
3) Documentation wording improved around the security_level setting
4) Logging improved around the security negotiation
5) Warnings now generated if Classic RDP security is negotiated
These Coverity warnings all relate to the user of g_setenv() where the
return result isn't checked.
An additional void function g_setenv_log() is provided which logs
failures to set environment variables, and returns no status. This is
used in all the places where g_setenv_is currently called.
xrdp contains two functions which do similar things:-
- g_htoi() converts a hex string to an integer, ignoring unrecognised
characters
- xrdp_wm_htoi() converts a hex string to an integer, ignoring leading
whitespace, but terminating on unrecognised characters
An analysis of the uses of g_htoi() shows that the only place where
unrecognised characters might be encountered is parsing lines from
xrdp_keyboard.ini, where all values have an '0x' prefix (i.e. the 'x'
is unrecognised)
An analysis of xrdp_wm_htoi() shows that the functionality to ignore
leading whitespace is not used.
Both functions are replaced with a re-written g_htoi() which is const-
correct and provided with test cases. This function behaves in
the same way as the atoi() library function, in that it terminates on
an unexpected character.
The use of g_htoi() in parsing lines from xrdp_keyboard.ini is replaced
with a call to g_atoix() which handles the '0x' prefix correctly.
Too many places in xrdp use strncpy() to copy strings to fixed-length
buffers, when this is not the correct function to use.
This PR makes sure strlcpy() from the BSDs is available as a saner
alternative. This function is available by default on Linux and FreeBSD.
matt335672