From 10b945c31de42660f8589e9d347601f6f0456fcf Mon Sep 17 00:00:00 2001
From: Hilko Bengen <bengen@hilluzination.de>
Date: Fri, 22 Oct 2021 17:50:37 +0200
Subject: [PATCH] Don't abuse PRNG -> fix identifier generation when building
 on Windows
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Pseudorandom number generators need to be initialized only once.

Using the system time for this is Generally Fine, but re-initializing
the PRNG in a tight loop every time a random number is needed
significantly raises the odds that the same number sequence (or even
the same number) is returned every time.

Chances for this to happen on Windows are apparently much higher than
on Linux. Not sure why this is the case, my best guess is that the
clock used for Go's `time.Now()´ runs with coarser granularity.
---
 Cryptor/Cryptor.go | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/Cryptor/Cryptor.go b/Cryptor/Cryptor.go
index 72d4061..69e0e06 100644
--- a/Cryptor/Cryptor.go
+++ b/Cryptor/Cryptor.go
@@ -24,6 +24,10 @@ var (
 	ErrInvalidPKCS7Padding = errors.New("invalid padding on input")
 )
 
+func init() {
+	crand.Seed(time.Now().UnixNano())
+}
+
 func Pkcs7Pad(b []byte, blocksize int) ([]byte, error) {
 	if blocksize <= 0 {
 		return nil, ErrInvalidBlockSize
@@ -58,7 +62,6 @@ func RandStringBytes(n int) string {
 
 func VarNumberLength(min, max int) string {
 	var r string
-	crand.Seed(time.Now().UnixNano())
 	num := crand.Intn(max-min) + min
 	n := num
 	r = RandStringBytes(n)
@@ -72,7 +75,6 @@ func printHexOutput(input ...[]byte) {
 }
 
 func GenerateNumer(min, max int) int {
-	crand.Seed(time.Now().UnixNano())
 	num := crand.Intn(max-min) + min
 	n := num
 	return n