Hi,
I've received the attached patch to make EVP_DecryptFinal_ex call
EVPerr() in case of an error.
I'm not sure if not calling EVPerr() is intentional or not.
Background: http://bugs.debian.org/768681, nodejs's test suite
fails because it's not getting the error anymore.
Kurt
From: William Bonnet <wllmb...@gmail.com>
Date: Sun, 16 Nov 2014 13:55:32 +0100
Subject: [PATCH] Fix for missing Bad Decrypt error code in EVP_DecryptFinal_ex
function.
When returning padding_good, the EVPerr is not called before returning zero,
leading to an undefined error code.
---
crypto/evp/evp_enc.c | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/crypto/evp/evp_enc.c b/crypto/evp/evp_enc.c
index 2f121ff..1a22584 100644
--- a/crypto/evp/evp_enc.c
+++ b/crypto/evp/evp_enc.c
@@ -546,6 +546,16 @@ int EVP_DecryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
out[i] = ctx->final[i] & padding_good;
/* Safe cast: for a good padding, EVP_MAX_IV_LENGTH >= b >= pad */
*outl = padding_good & ((unsigned char)(b - pad));
+
+ /*
+ * If the padding_good variable is 0 then a decryption problem occured
+ * and we have to call EVPerr before returning 0
+ */
+ if ((padding_good & 1) == 0)
+ {
+ EVPerr(EVP_F_EVP_DECRYPTFINAL_EX, EVP_R_BAD_DECRYPT);
+ }
+
return padding_good & 1;
}
else
--
2.1.1
