crypto: crypto4xx - block ciphers should only accept complete blocks

The hardware automatically zero pads incomplete block ciphers
blocks without raising any errors. This is a screw-up. This
was noticed by CONFIG_CRYPTO_MANAGER_EXTRA_TESTS tests that
sent a incomplete blocks and expect them to fail.

This fixes:
cbc-aes-ppc4xx encryption unexpectedly succeeded on test vector
"random: len=2409 klen=32"; expected_error=-22, cfg="random:
may_sleep use_digest src_divs=[96.90%@+2295, 2.34%@+4066,
0.32%@alignmask+12, 0.34%@+4087, 0.9%@alignmask+1787, 0.1%@+3767]
iv_offset=6"

ecb-aes-ppc4xx encryption unexpectedly succeeded on test vector
"random: len=1011 klen=32"; expected_error=-22, cfg="random:
may_sleep use_digest src_divs=[100.0%@alignmask+20]
dst_divs=[3.12%@+3001, 96.88%@+4070]"

Cc: Eric Biggers <ebiggers@kernel.org>
Cc: stable@vger.kernel.org [4.19, 5.0 and 5.1]
Signed-off-by: Christian Lamparter <chunkeey@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

1 files changed, 25 insertions, 11 deletions

diff --git a/drivers/crypto/amcc/crypto4xx_alg.c b/drivers/crypto/amcc/crypto4xx_alg.c
index 307f5cfa9ba4..26f86fd7532b 100644
--- a/drivers/crypto/amcc/crypto4xx_alg.c
+++ b/drivers/crypto/amcc/crypto4xx_alg.c
@@ -76,12 +76,16 @@ static void set_dynamic_sa_command_1(struct dynamic_sa_ctl *sa, u32 cm,
 }
 
 static inline int crypto4xx_crypt(struct skcipher_request *req,
-				  const unsigned int ivlen, bool decrypt)
+				  const unsigned int ivlen, bool decrypt,
+				  bool check_blocksize)
 {
 	struct crypto_skcipher *cipher = crypto_skcipher_reqtfm(req);
 	struct crypto4xx_ctx *ctx = crypto_skcipher_ctx(cipher);
 	__le32 iv[AES_IV_SIZE];
 
+	if (check_blocksize && !IS_ALIGNED(req->cryptlen, AES_BLOCK_SIZE))
+		return -EINVAL;
+
 	if (ivlen)
 		crypto4xx_memcpy_to_le32(iv, req->iv, ivlen);
 
@@ -90,24 +94,34 @@ static inline int crypto4xx_crypt(struct skcipher_request *req,
 		ctx->sa_len, 0, NULL);
 }
 
-int crypto4xx_encrypt_noiv(struct skcipher_request *req)
+int crypto4xx_encrypt_noiv_block(struct skcipher_request *req)
+{
+	return crypto4xx_crypt(req, 0, false, true);
+}
+
+int crypto4xx_encrypt_iv_stream(struct skcipher_request *req)
+{
+	return crypto4xx_crypt(req, AES_IV_SIZE, false, false);
+}
+
+int crypto4xx_decrypt_noiv_block(struct skcipher_request *req)
 {
-	return crypto4xx_crypt(req, 0, false);
+	return crypto4xx_crypt(req, 0, true, true);
 }
 
-int crypto4xx_encrypt_iv(struct skcipher_request *req)
+int crypto4xx_decrypt_iv_stream(struct skcipher_request *req)
 {
-	return crypto4xx_crypt(req, AES_IV_SIZE, false);
+	return crypto4xx_crypt(req, AES_IV_SIZE, true, false);
 }
 
-int crypto4xx_decrypt_noiv(struct skcipher_request *req)
+int crypto4xx_encrypt_iv_block(struct skcipher_request *req)
 {
-	return crypto4xx_crypt(req, 0, true);
+	return crypto4xx_crypt(req, AES_IV_SIZE, false, true);
 }
 
-int crypto4xx_decrypt_iv(struct skcipher_request *req)
+int crypto4xx_decrypt_iv_block(struct skcipher_request *req)
 {
-	return crypto4xx_crypt(req, AES_IV_SIZE, true);
+	return crypto4xx_crypt(req, AES_IV_SIZE, true, true);
 }
 
 /**
@@ -278,8 +292,8 @@ crypto4xx_ctr_crypt(struct skcipher_request *req, bool encrypt)
 		return ret;
 	}
 
-	return encrypt ? crypto4xx_encrypt_iv(req)
-		       : crypto4xx_decrypt_iv(req);
+	return encrypt ? crypto4xx_encrypt_iv_stream(req)
+		       : crypto4xx_decrypt_iv_stream(req);
 }
 
 static int crypto4xx_sk_setup_fallback(struct crypto4xx_ctx *ctx,