This project introduces a pseudorandom generator device for Linux, based on a 64-bit Fibonacci LFSR.
The feedback polynomial is:
2⁶⁴ + 2⁶² + 2⁶¹ + 2⁵⁹ + 1
This kernel module installs a device file at /dev/lfsr.
| Operation |
Effect |
| Read |
Consumes data from the device. |
| Write |
Sets the generator seed (requires 8 bytes or more). |
- Linux Kernel headers.
- GNU Make.
- gcc compiler.
| Platform |
Command |
| Debian / Ubuntu |
apt install make gcc linux-headers-`uname -r` |
| Red Hat / Fedora |
dnf install make gcc kernel-devel elfutils-libelf-devel |
Note: Inserting an unsigned module into the Linux Kernel will taint it.
| Platform |
Command |
| Debian / Ubuntu |
apt install make g++ |
| Red Hat / Fedora |
dnf install make gcc-c++ |
rand-test [-h] [-s SIZE] [ GEN ... ]
| Option |
Range |
Default |
Description |
-h |
|
|
Print help. |
-s |
4-9223372036854775807 |
1073741824 (1 GiB) |
Define the data length. |
| Generator |
Description |
CRandom |
C linear congruential generator. |
LFSR |
/dev/lfsr |
Mersenne |
MT19937 Mersenne Twister. |
URandom |
/dev/urandom |
| Generator |
Time |
Performance |
| CRandom |
711.984 ms. |
1508.1 MB/s. |
| LFSR |
416.378 ms. |
2746.55 MB/s. |
| Mersenne |
1241.43 ms. |
864.923 MB/s. |
| URandom |
2122.14 ms. |
505.97 MB/s. |
| Version |
Peak throughput |
Cost per shift |
Improvement over v0.1 |
| 0.1 |
84.2231 MB/s. |
576 ops. |
- |
| 0.2 |
140.919 MB/s. |
560 ops. |
67.32 % |
| 0.3 |
184.154 MB/s. |
400 ops. |
2.187 X |
| 0.4 |
2336.51 MB/s. |
18 ops. |
32.61 X |
| Peak throughput (higher is better) |
Cost per shifting (lower is better) |
 |
 |
| Processor |
Memory |
OS |
| Intel i7 11700 2.5 GHz |
DDR4 32 GB 3200 MHz |
Ubuntu 22.04 @ VirtualBox 7 |