If swtpm becomes unresponsive, guest gets blocked at "recvmsg" on tpm's
data FD. This change adds a timeout to the data fd socket. If swtpm
becomes unresponsive guest waits for "timeout" (secs) and continues to
run after returning an I/O error to tpm commands.
Signed-off-by: Praveen K Paladugu <prapal@linux.microsoft.com>
There is no guarantee that the write can send the whole buffer at once.
In those rare occasions, we should return a sensible error.
Signed-off-by: Wei Liu <liuwe@microsoft.com>
The largest possible PTM response is only 16 bytes. Size the output
buffer correctly.
In the socket read function, rely on the caller to provide a
sufficiently large buffer. That eliminates another large stack variable.
In total this saves almost 8KB stack space.
Signed-off-by: Wei Liu <liuwe@microsoft.com>
Make the code more idiomatic by wrapping the actual size configured in
the returning Result type. This further allows simplifying
get_buffer_size.
The debug message in startup_tpm is more useful if it prints out the
actual size than the wanted size.
No functional change.
Signed-off-by: Wei Liu <liuwe@microsoft.com>
Emulator module adds methods required to communicate with swtpm
over Ctrl and Data channels.
Signed-off-by: Praveen K Paladugu <prapal@linux.microsoft.com>
Co-authored-by: Sean Yoo <t-seanyoo@microsoft.com>
