crypto/mlkem/mlkemtest: error out in fips140=only mode

Updates #70514

Change-Id: I1d1a0b4a2c7ee4cb6e8e0700dd3463a46a6a6964
Reviewed-on: https://go-review.googlesource.com/c/go/+/728502
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Roland Shoemaker <roland@golang.org>
Auto-Submit: Filippo Valsorda <filippo@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>

diff --git a/src/crypto/mlkem/mlkemtest/mlkemtest.go b/src/crypto/mlkem/mlkemtest/mlkemtest.go
index 39e3994ea9beb2c995dbd329720f2d4bd3aa8fc8..40f64862bd49eb1fa6760f6e14e630fd5d97aea5 100644 (file)
--- a/src/crypto/mlkem/mlkemtest/mlkemtest.go
+++ b/src/crypto/mlkem/mlkemtest/mlkemtest.go
@@ -7,6 +7,7 @@ package mlkemtest
 
 import (
        fips140mlkem "crypto/internal/fips140/mlkem"
+       "crypto/internal/fips140only"
        "crypto/mlkem"
        "errors"
 )
@@ -20,6 +21,9 @@ func Encapsulate768(ek *mlkem.EncapsulationKey768, random []byte) (sharedKey, ci
        if len(random) != 32 {
                return nil, nil, errors.New("mlkemtest: Encapsulate768: random must be 32 bytes")
        }
+       if fips140only.Enforced() {
+               return nil, nil, errors.New("crypto/mlkem/mlkemtest: use of derandomized encapsulation is not allowed in FIPS 140-only mode")
+       }
        k, err := fips140mlkem.NewEncapsulationKey768(ek.Bytes())
        if err != nil {
                return nil, nil, errors.New("mlkemtest: Encapsulate768: failed to reconstruct key: " + err.Error())
@@ -37,6 +41,9 @@ func Encapsulate1024(ek *mlkem.EncapsulationKey1024, random []byte) (sharedKey,
        if len(random) != 32 {
                return nil, nil, errors.New("mlkemtest: Encapsulate1024: random must be 32 bytes")
        }
+       if fips140only.Enforced() {
+               return nil, nil, errors.New("crypto/mlkem/mlkemtest: use of derandomized encapsulation is not allowed in FIPS 140-only mode")
+       }
        k, err := fips140mlkem.NewEncapsulationKey1024(ek.Bytes())
        if err != nil {
                return nil, nil, errors.New("mlkemtest: Encapsulate1024: failed to reconstruct key: " + err.Error())