From dffe51091f412dcbc18f6641132f0b4f0def6bce Mon Sep 17 00:00:00 2001 From: Matt Caswell Date: Thu, 8 Oct 2015 13:36:10 +0100 Subject: [PATCH] Don't treat a bare OCTETSTRING as DigestInfo in int_rsa_verify The function int_rsa_verify is an internal function used for verifying an RSA signature. It takes an argument |dtype| which indicates the digest type that was used. Dependant on that digest type the processing of the signature data will vary. In particular if |dtype == NID_mdc2| and the signature data is a bare OCTETSTRING then it is treated differently to the default case where the signature data is treated as a DigestInfo (X509_SIG). Due to a missing "else" keyword the logic actually correctly processes the OCTETSTRING format signature first, and then attempts to continue and process it as DigestInfo. This will invariably fail because we already know that it is a bare OCTETSTRING. This failure doesn't actualy make a real difference because it ends up at the |err| label regardless and still returns a "success" result. This patch just cleans things up to make it look a bit more sane. RT#4076 Reviewed-by: Richard Levitte --- crypto/rsa/rsa_sign.c | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-) diff --git a/crypto/rsa/rsa_sign.c b/crypto/rsa/rsa_sign.c index ff70cd9464..9f4649aef9 100644 --- a/crypto/rsa/rsa_sign.c +++ b/crypto/rsa/rsa_sign.c @@ -200,14 +200,13 @@ int int_rsa_verify(int dtype, const unsigned char *m, memcpy(rm, s + 2, 16); *prm_len = 16; ret = 1; - } else if (memcmp(m, s + 2, 16)) + } else if (memcmp(m, s + 2, 16)) { RSAerr(RSA_F_INT_RSA_VERIFY, RSA_R_BAD_SIGNATURE); - else + } else { ret = 1; - } - - /* Special case: SSL signature */ - if (dtype == NID_md5_sha1) { + } + } else if (dtype == NID_md5_sha1) { + /* Special case: SSL signature */ if ((i != SSL_SIG_LENGTH) || memcmp(s, m, SSL_SIG_LENGTH)) RSAerr(RSA_F_INT_RSA_VERIFY, RSA_R_BAD_SIGNATURE); else -- 2.25.1