goos: linux

goarch: amd64 pkg: github.com/komuw/ong/cry cpu: Intel(R) Core(TM) i5-6300U CPU @ 2.40GHz │ old.txt │ new.txt │ │ sec/op │ sec/op vs base │ Enc-4 5.713µ ± 6% 5.756µ ± 7% ~ (p=0.853 n=10) │ old.txt │ new.txt │ │ B/op │ B/op vs base │ Enc-4 672.0 ± 0% 672.0 ± 0% ~ (p=1.000 n=10) ¹ ¹ all samples are equal │ old.txt │ new.txt │ │ allocs/op │ allocs/op vs base │ Enc-4 14.00 ± 0% 14.00 ± 0% ~ (p=1.000 n=10) ¹ ¹ all samples are equal
komuw · Aug 29, 2024 · e005114 · e005114
1 parent b3a0874
commit e005114
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Showing 2 changed files with 18 additions and 16 deletions.
diff --git a/cry/enc.go b/cry/enc.go
@@ -114,10 +114,13 @@ func (e Enc) Encrypt(plainTextMsg string) (encryptedMsg []byte) {
 
 	// Select a random nonce.
 	// https://github.com/golang/crypto/blob/v0.26.0/chacha20poly1305/chacha20poly1305_test.go#L222
-	nonce := random(chacha20poly1305.NonceSizeX, chacha20poly1305.NonceSizeX)
+	nonce := random(
+		chacha20poly1305.NonceSizeX,
+		chacha20poly1305.NonceSizeX+len(msgToEncrypt)+chacha20poly1305.Overhead,
+	)
 
-	// Encrypt while reusing plaintext's storage for the encrypted output.
-	encrypted := e.aead.Seal(msgToEncrypt[:0], nonce, msgToEncrypt, nil)
+	// Encrypt the message and append the ciphertext to the nonce.
+	encrypted := e.aead.Seal(nonce, nonce, msgToEncrypt, nil)
 
 	// Append the salt & nonce to encrypted msg.
 	// |salt|nonce|encryptedMsg|
@@ -127,10 +130,9 @@ func (e Enc) Encrypt(plainTextMsg string) (encryptedMsg []byte) {
 		//
 		// "salt does not need to be secret."
 		// see: https://crypto.stackexchange.com/a/99502
-		nonce,
+		e.salt,
 		encrypted...,
 	)
-	encrypted = append(e.salt, encrypted...)
 
 	return encrypted
 }

diff --git a/new.txt b/new.txt
@@ -2,15 +2,15 @@ goos: linux
 goarch: amd64
 pkg: github.com/komuw/ong/cry
 cpu: Intel(R) Core(TM) i5-6300U CPU @ 2.40GHz
-BenchmarkEnc-4   	  198574	      5729 ns/op	     728 B/op	      16 allocs/op
-BenchmarkEnc-4   	  196320	      6186 ns/op	     728 B/op	      16 allocs/op
-BenchmarkEnc-4   	  182754	      6660 ns/op	     728 B/op	      16 allocs/op
-BenchmarkEnc-4   	  197444	      5698 ns/op	     728 B/op	      16 allocs/op
-BenchmarkEnc-4   	  208227	      5659 ns/op	     728 B/op	      16 allocs/op
-BenchmarkEnc-4   	  205922	      5794 ns/op	     728 B/op	      16 allocs/op
-BenchmarkEnc-4   	  206336	      5606 ns/op	     728 B/op	      16 allocs/op
-BenchmarkEnc-4   	  222356	      5653 ns/op	     728 B/op	      16 allocs/op
-BenchmarkEnc-4   	  198865	      6238 ns/op	     728 B/op	      16 allocs/op
-BenchmarkEnc-4   	  186834	      5660 ns/op	     728 B/op	      16 allocs/op
+BenchmarkEnc-4   	  168698	      5992 ns/op	     672 B/op	      14 allocs/op
+BenchmarkEnc-4   	  204858	      5794 ns/op	     672 B/op	      14 allocs/op
+BenchmarkEnc-4   	  207462	      5717 ns/op	     672 B/op	      14 allocs/op
+BenchmarkEnc-4   	  193176	      5851 ns/op	     672 B/op	      14 allocs/op
+BenchmarkEnc-4   	  167646	      6160 ns/op	     672 B/op	      14 allocs/op
+BenchmarkEnc-4   	  210864	      5449 ns/op	     672 B/op	      14 allocs/op
+BenchmarkEnc-4   	  201039	      5514 ns/op	     672 B/op	      14 allocs/op
+BenchmarkEnc-4   	  162837	      6249 ns/op	     672 B/op	      14 allocs/op
+BenchmarkEnc-4   	  212643	      5664 ns/op	     672 B/op	      14 allocs/op
+BenchmarkEnc-4   	  188997	      5665 ns/op	     672 B/op	      14 allocs/op
 PASS
-ok  	github.com/komuw/ong/cry	16.162s
+ok  	github.com/komuw/ong/cry	15.550s