Implement new patty client code, replacing src/call.c with src/client.c
providing clients with an interface dealing with file descriptors valid
in their process space; this also obviates the need to open a Unix
domain socket to a patty server explicitly, and helps keep track of
sockets opened on the server, locally
Changes:
* Implement patty_client_new() to handle opening the server Unix
domain socket, and to allocate a dict for mapping server-side
sockets with current process file descriptors
* Reimplement all server calls in src/call.c around the new
patty_client type; calls which result in the creation of a
Unix98 PTY by the patty server now handle opening the local PTY
and setting the file descriptor to raw mode. Furthermore, these
calls deal exclusively in terms of current process file
descriptors
* Refactor src/server.c to use the new patty_client type and calls
* Refactor examples/client.c, examples/server.c, examples/ax25dump.c
to use the new patty_client type and calls
* Fix a bug in src/server.c, respond_accept() wherein a 0, rather
than the file descriptor of the socket, is sent to the client as a
return value
More strictly adhere to the behaviors of Timers T1, T2 and T3 as
prescribed in the AX.25 v2.2 Specification, Section 4.4.5 "Timeout Error
Recovery" descriptions for Timer T1 and T3, as well as Section 6.7.1.2
"Response Delay Timer T2"
Changes:
* Implement patty_timer type to store both a struct timeval and a
bitfield for indicating timer state; currently, this only holds
the PATTY_TIMER_RUNNING flag to indicate whether a timer has been
stopped (irrespective of its "expired" status)
* Remove 'target' argument from patty_timer_start(); instead, rely
on select() polling every 1s to cause events to trigger at a
regular interval
* Make patty_timer_expired() return false if PATTY_TIMER_RUNNING is
not set
* Implement patty_timer_stop() to clear the PATTY_TIMER_RUNNING flag
of a timer
* Make patty_timer_clear() set all fields to zero, including
clearing the PATTY_TIMER_RUNNING flag
Implement AX.25 v2.2 Section 6.7.1.2 "Response Delay Timer T2" as per
specification; do not acknowledge several sequential I frames until a
certain period of time has passed since the receipt of the most recent I
frame
Changes:
* Implement patty_timer_expired() to determine if a timer has
expired or has gone negative
* Implement patty_timer_cancel() to set a timer to zero
* Implement patty_timer_start() to initialize a timer, add a
specified number of milliseconds, and ensure a target timer (such
as the server timer) is set for at least that value as well
* Implement patty_timer_tick() to subtract an elapsed time value
from a timer
* Remove functions specific to each timer in src/sock.c, as those
can now be handled generically by src/timer.c
* Replace calls to patty_ax25_sock_timer_t1_*() with patty_timer_*()
calls instead; reference the struct timeval objects directly
within the sock (for the time being, pending opaque structures)
Changes:
* Combine patty_ax25_sock_ack_timer_restart() and _set() into one
method, patty_ax25_sock_ack_timer_start(), which accepts a new
struct timeval argument to potentially add the Timer T1 value to
* Reorder some functions in src/sock.c, include/patty/ax25/sock.h
Begin to reimplement patty_ax25_sock_reset() to follow the AX.25 v2.2
Specification, Section 6.5 "Resetting Procedure" indications to set V(S)
and V(R) to 0
Rename patty_ax25_sock_reset() to patty_ax25_sock_init(), so as to allow
for the implementation of a future _reset() method which shall be used
to implement AX.25 v2.2 Section 6.5 "Resetting Procedure"
Changes:
* Make patty_ax25_sock_send_rr() accept a P/F flag value
* Make patty_ax25_sock_send_rnr() accept a P/F flag value
* Make patty_ax25_sock_send_rej() accept a P/F flag value
Changes:
* Allow REJ handling to occur when the V(S) send state counter wraps
to a value lower than indicated in the frame N(R) field
* Fix tx_slot() in src/sock.c to not buffer overflow when the TX
window is less than the maximum for the SABM/SABME mode
Changes:
* Add an enum patty_ax25_version argument to the function
patty_ax25_sock_upgrade() to allow upgrading a socket to a certain
set of AX.25 defaults
Changes:
* Implement and use respond_accept() and respond_connect()
convenience methods instead of stack allocating response objects,
populating them, and using write() to send them to the client
* When receiving XID frames in response to either an accept() or
connect() call, respond to the client if any of the parameters
sent from the peer are not compatible with a socket or interface,
with the appropriate errno value
Changes:
* Make bind() validate that no other socket has the same
callsign/SSID bound to a listening socket, emitting EADDRINUSE if
one already exists
* Make bind() validate that no address is already bound to the
socket, emitting EINVAL otherwise
Changes:
* Add a "pending disconnect" state to enum patty_ax25_sock_state
(PATTY_AX25_SOCK_PENDING_DISCONNECT), used when an originating
system sends a DISC frame, pending a UA response
* When handling a UA frame, rather than terminating a socket in the
established state implicitly, check for a "pending disconnect"
state explicitly
Other changes:
* When a remote socket has already been obtained in handle_frame()
in src/server.c, pass that socket to any other method that would
otherwise be looking up the same socket
Changes:
* Don't use a separate dict for keeping track of sockets pending
accept and sockets pending connect; rely more on the semantic
meaning of the enum patty_ax25_sock_status values
* Ensure DISC frames are acknowledged by UA frames
* Ensure a receiving system only shuts down a connection after
receiving a UA frame in response to a sent DISC frame
* Ensure a sending system only shuts down a connection just prior to
sending a UA frame in response to a received DISC frame
* Don't use the P/F flag for the connection management U frames;
implicitly assume the P/F flag is set to 1, and always send frames
with a true P/F flag
Changes:
* Replace patty_ax25_sock member 'buf' with 'tx_buf' and 'rx_buf'
for transmitting or receiving single, non-sequential packets
* Make patty_ax25_sock_upgrade() reallocate all I/O buffers based on
window size and MTU/MRU, useful when entering SABME mode
Changes:
* Modify patty_ax25_sock_send_xid() to require the 'cr' argument,
which specifies whether the frame address field is to be encoded
with the 'command' or 'response' bits set as appropriate
Changes:
* Add 'format' member to patty_ax25_frame
* Drop 'format' argument in patty_ax25_encode_reply_to()
* Drop 'format' argument in patty_ax25_encode()
* Consolidate private functions for encoding frame addresses to one
much simpler function to perform encoding; simplify encoding of
addresses in frames sent in reply to other frames
Implement the AX.25 v2.2 XID parameter exchange as a preamble for
initiating connections with peers, with the following workflow:
* Upon a connect() call, send an XID frame to the peer
* When a DM is received, assume the peer is unable to accept a
connection
* When a FRMR is received, assume the peer does not adhere to the
AX.25 v2.2 standard, and attempt to initiate a connection with a
SABM frame instead
* When an XID is received, adapt local parameters to meet the
needs of the peer, and respond with an SABM or an SABME frame,
depending on which mode is indicated
Use patty_ax25_sock_bind_if() in server_connect() to ensure any other
functions which must take place are attended to when assigning an
interface to a socket
Changes:
* Implement patty_ax25_params struct to contain all parameters
supported by patty, at the interface and socket level alike
* Move parameter enumerate types into include/patty/ax25.h, from
include/patty/ax25/frame.h; make corrections as necessary
* Reimplement patty_ax25_frame_decode_xid() to parse known XID
information parameters into a patty_ax25_params object
* Implement patty_print_params() in src/print.c
* Refactor patty_print_frame() as patty_print_frame_header(),
without a call to patty_print_hexdump(); this allows
patty_print_params() to be called prior to patty_print_hexdump(),
for better readability
* Use patty_print_params() in examples/ax25dump.c, decode.c
* Refactor usage of patty_ax25_frame_decode_xid() in src/server.c to
parse XID frames into a patty_ax25_params object
Implement ring buffer for frames sent in a SABM or SABME session,
facilitating the ability to retransmit select frames upon request,
retaining a copy of the full frame and its transmitted size
Implement better handling of command/response bits whilst decoding and
encoding addresses
Changes:
* Add an enum patty_ax25_frame_cr argument to functions in
src/sock.c which send specific types of frames
* Detect AX.25 version >2.0 based on the command/response SSID bits
* Simplify address copying/encoding by usage of the new function
patty_ax25_addr_copy()
* Implement showing AX.25 version, command/response indicator for
frames in src/print.c
Implement better handling of situations when read() captures multiple
TNC frames; ensure each frame is handled in src/server.c, function
handle_iface(), to ensure packets aren't ignored before the next
select() call
Changes:
* Split patty_ax25_frame_decode() into the following:
- patty_ax25_frame_decode_address()
- patty_ax25_frame_decode_control()
This allows for look up an established socket for a given address
pair, to determine if an SABME session is in progress,
necessitating modulo-128 control decoding
* Decode I and S N(R), N(S) sequence numbers, poll/final
bits properly in both modulo-8 and modulo-128 mode
* Perform better frame control validation
* Implement the following functions in src/sock.c:
- patty_ax25_sock_send_rr()
- patty_ax25_sock_send_rnr()
- patty_ax25_sock_send_rej()
- patty_ax25_sock_send_srej()
Corresponding functions have been removed from src/server.c
* Implement better functions in src/sock.c for encoding frame
control, with send/receive sequences associated with the socket,
with modulo-128 encoding for SABME sessions
Other changes:
* Move or delete macros from include/patty/ax25/macros.h into
include/patty/ax25.h and include/patty/ax25/frame.h
* Move definitions from include/patty/ax25/proto.h to header file
include/patty/ax25.h
* Perform better bounds checking while decoding frames
* Improve frame control printing in src/print.c; display frame
type names, N(R), (NS) sequence numbers, and poll/final bits
Significantly simplify dictionaries so that dictionary keys are always
uint32_t; this number can be an arbitrary integer, be it a file
descriptor, for instance, or a hashed value
