crypto/cipher: block non-AES CTR and CBC in fips140=only mode

Somehow I had missed these.

For #69536

Change-Id: I5e60b6f052bbfb707742ad15f663517c6c5f68d3
Reviewed-on: https://go-review.googlesource.com/c/go/+/636795
Auto-Submit: Filippo Valsorda <filippo@golang.org>
Reviewed-by: Roland Shoemaker <roland@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: David Chase <drchase@google.com>

2 files changed, 11 insertions, 0 deletions

diff --git a/src/crypto/cipher/cbc.go b/src/crypto/cipher/cbc.go
index b4536aceb9..8e61406296 100644
--- a/src/crypto/cipher/cbc.go
+++ b/src/crypto/cipher/cbc.go
@@ -15,6 +15,7 @@ import (
 	"bytes"
 	"crypto/internal/fips140/aes"
 	"crypto/internal/fips140/alias"
+	"crypto/internal/fips140only"
 	"crypto/subtle"
 )
 
@@ -53,6 +54,9 @@ func NewCBCEncrypter(b Block, iv []byte) BlockMode {
 	if b, ok := b.(*aes.Block); ok {
 		return aes.NewCBCEncrypter(b, [16]byte(iv))
 	}
+	if fips140only.Enabled {
+		panic("crypto/cipher: use of CBC with non-AES ciphers is not allowed in FIPS 140-only mode")
+	}
 	if cbc, ok := b.(cbcEncAble); ok {
 		return cbc.NewCBCEncrypter(iv)
 	}
@@ -129,6 +133,9 @@ func NewCBCDecrypter(b Block, iv []byte) BlockMode {
 	if b, ok := b.(*aes.Block); ok {
 		return aes.NewCBCDecrypter(b, [16]byte(iv))
 	}
+	if fips140only.Enabled {
+		panic("crypto/cipher: use of CBC with non-AES ciphers is not allowed in FIPS 140-only mode")
+	}
 	if cbc, ok := b.(cbcDecAble); ok {
 		return cbc.NewCBCDecrypter(iv)
 	}
diff --git a/src/crypto/cipher/ctr.go b/src/crypto/cipher/ctr.go
index c868635b8a..49512ca5dd 100644
--- a/src/crypto/cipher/ctr.go
+++ b/src/crypto/cipher/ctr.go
@@ -16,6 +16,7 @@ import (
 	"bytes"
 	"crypto/internal/fips140/aes"
 	"crypto/internal/fips140/alias"
+	"crypto/internal/fips140only"
 	"crypto/subtle"
 )
 
@@ -41,6 +42,9 @@ func NewCTR(block Block, iv []byte) Stream {
 	if block, ok := block.(*aes.Block); ok {
 		return aesCtrWrapper{aes.NewCTR(block, iv)}
 	}
+	if fips140only.Enabled {
+		panic("crypto/cipher: use of CTR with non-AES ciphers is not allowed in FIPS 140-only mode")
+	}
 	if ctr, ok := block.(ctrAble); ok {
 		return ctr.NewCTR(iv)
 	}