drmdecrypt

Synopsis

drmdecrypt is a tool to decrypt recorded files from Samsung TVs into standard transport stream format. There are multiple similar versions out there based on code from SamyGO and various people but they are all either slow, Windows specific, full of bugs or even all together.

This version is fast, POSIX compliant (Linux, FreeBSD, Windows (MinGW)) and is focused on a small number of useful features.

Features

• Reading title and channel from .inf file
• Bulk decoding multiple files
• AES-NI support (5x faster)

Usage

Usage: drmdecrypt [-dqvx][-o outdir] infile.srf ...
Options:
   -d         Show debugging output
   -o outdir  Output directory
   -q         Be quiet. Only error output.
   -v         Version information
   -x         Disable AES-NI support

Building / Installing

make
make install

Tested with

• Samsung Series C, D

TODO

• Test with Samsung Series E, F
• Internal I/O buffer for decrypting
• default ist BUFSIZ oder besser struct fstat blocksize
• I/O write: write() + O_DIRECT + posix_memalign()
• I/O read: fread(188) + setvbuf(32k+8, _IOFBF)
• OpenMP for multiprocessing: #pragma omp parallel for schedule(static)
• Test with Samsung Series D, E, F
• compiler flags https://software.intel.com/en-us/blogs/2012/09/26/gcc-x86-performance-hints