hi , i am developing a device upper filter driver for audio device that will also save the streams passing through it. to process the data , i am trying to intercept IRP_MJ_DEVICE_CONTROL IRPs with following IoControl codes.
I defined them as below.
#define IOCTL_KS_READ_STREAM CTL_CODE(FILE_DEVICE_KS, 0x005, METHOD_NEITHER, FILE_ANY_ACCESS) #define IOCTL_KS_WRITE_STREAM CTL_CODE(FILE_DEVICE_KS, 0x004, METHOD_NEITHER, FILE_WRITE_ACCESS)
while a sound was being played and i tried to interecept IOCTL_KS_READ_STREAM in deviceIocontrol routine i could not recieve irps with this iocontrol code.
when i printed above devclared IOCTL_KS_READ_STREAM and recieved code while debugging their values are printed as below
declared IOCTL_KS_READ_STREAM code : 3080215 recieved io control code: 3080195
the recieved code is equal to as defined below with function code 0x000
CTL_CODE(FILE_DEVICE_KS, 0x000, METHOD_NEITHER, FILE_ANY_ACCESS)
where does the problem lies. am i declaring IOCTL_KS_READ_STREAM with wrong function code ? and recieved irp with above io control code corresponds to what??? i want to intercept IOCTL_KS_READ_STREAM and save the stream to ta file in wave format. am i following the correct approach?
2ndly if i get the data buffer through irp. what is the procedure to save that data to file?
looking forward for your response... Regards ___________ Saad Bashir