Use crypto/pbkdf2.

tests/blob_test.go

@@ -45,10 +45,7 @@ func TestBlob(t *testing.T) {
 	}
 
 	var data [1280]byte
-	_, err = rand.Read(data[:])
-	if err != nil {
-		t.Fatal(err)
-	}
+	rand.Read(data[:])
 
 	_, err = blob.Write(data[:size/2])
 	if err != nil {

vfs/adiantum/adiantum.go

@@ -25,8 +25,8 @@ func (adiantumCreator) HBSH(key []byte) *hbsh.HBSH {
 func (adiantumCreator) KDF(text string) []byte {
 	if text == "" {
 		key := make([]byte, 32)
-		n, _ := rand.Read(key)
-		return key[:n]
+		rand.Read(key)
+		return key
 	}
 	return argon2.IDKey([]byte(text), []byte(pepper), 3, 64*1024, 4, 32)
 }

vfs/adiantum/example_test.go

@@ -45,8 +45,8 @@ func (hpolycCreator) KDF(secret string) []byte {
 	if secret == "" {
 		// No secret is given, generate a random key.
 		key := make([]byte, 32)
-		n, _ := rand.Read(key)
-		return key[:n]
+		rand.Read(key)
+		return key
 	}
 	// Hash the secret with a KDF.
 	return argon2.IDKey([]byte(secret), []byte("hpolyc"), 3, 64*1024, 4, 32)

vfs/xts/README.md

@@ -9,12 +9,12 @@ In general, any XTS construction can be used to wrap any VFS.
 
 The default AES-XTS construction uses AES-128, AES-192, or AES-256
 for its block cipher.
-Additionally, we use [PBKDF2-HMAC-SHA512](https://pkg.go.dev/golang.org/x/crypto/pbkdf2)
+Additionally, we use [PBKDF2-HMAC-SHA512](https://pkg.go.dev/crypto/pbkdf2)
 to derive AES-128 keys from plain text where needed.
 File contents are encrypted in 512 byte sectors, matching the
 [minimum](https://sqlite.org/fileformat.html#pages) SQLite page size.
 
-This VFS uses _only_ NIST and FIPS 140-2 approved cryptographic primitives,
+This VFS uses _only_ NIST and FIPS 140-3 approved cryptographic primitives,
 which _may_ help you become FIPS compliant.
 
 The VFS encrypts all files _except_

vfs/xts/aes.go

@@ -2,10 +2,10 @@ package xts
 
 import (
 	"crypto/aes"
+	"crypto/pbkdf2"
 	"crypto/rand"
 	"crypto/sha512"
 
-	"golang.org/x/crypto/pbkdf2"
 	"golang.org/x/crypto/xts"
 )
 
@@ -27,8 +27,12 @@ func (aesCreator) XTS(key []byte) *xts.Cipher {
 func (aesCreator) KDF(text string) []byte {
 	if text == "" {
 		key := make([]byte, 32)
-		n, _ := rand.Read(key)
-		return key[:n]
+		rand.Read(key)
+		return key
 	}
-	return pbkdf2.Key([]byte(text), []byte(pepper), 10_000, 32, sha512.New)
+	key, err := pbkdf2.Key(sha512.New, text, []byte(pepper), 10_000, 32)
+	if err != nil {
+		panic(err)
+	}
+	return key
 }