Commit 70428ead authored by Kurt Roeckx's avatar Kurt Roeckx Committed by Matt Caswell
Browse files

Check that we have enough padding characters. 



Reviewed-by: default avatarEmilia Käsper <emilia@openssl.org>

CVE-2016-2107

MR: #2572
parent 2c7fe4dc

crypto/evp/e_aes_cbc_hmac_sha1.c

+3 −0
Original line number Diff line number Diff line
@@ -59,6 +59,7 @@ 
#include <openssl/rand.h>

#include "modes_lcl.h"

#include "internal/evp_int.h"

#include "internal/constant_time_locl.h"



#ifndef EVP_CIPH_FLAG_AEAD_CIPHER

# define EVP_CIPH_FLAG_AEAD_CIPHER       0x200000
@@ -583,6 +584,8 @@ static int aesni_cbc_hmac_sha1_cipher(EVP_CIPHER_CTX *ctx, unsigned char *out, 
            maxpad |= (255 - maxpad) >> (sizeof(maxpad) * 8 - 8);

            maxpad &= 255;



            ret &= constant_time_ge(maxpad, pad);



            inp_len = len - (SHA_DIGEST_LENGTH + pad + 1);

            mask = (0 - ((inp_len - len) >> (sizeof(inp_len) * 8 - 1)));

            inp_len &= mask;

crypto/evp/e_aes_cbc_hmac_sha256.c

+3 −0
Original line number Diff line number Diff line
@@ -59,6 +59,7 @@ 
#include <openssl/sha.h>

#include <openssl/rand.h>

#include "modes_lcl.h"

#include "internal/constant_time_locl.h"

#include "internal/evp_int.h"



#ifndef EVP_CIPH_FLAG_AEAD_CIPHER
@@ -594,6 +595,8 @@ static int aesni_cbc_hmac_sha256_cipher(EVP_CIPHER_CTX *ctx, 
            maxpad |= (255 - maxpad) >> (sizeof(maxpad) * 8 - 8);

            maxpad &= 255;



            ret &= constant_time_ge(maxpad, pad);



            inp_len = len - (SHA256_DIGEST_LENGTH + pad + 1);

            mask = (0 - ((inp_len - len) >> (sizeof(inp_len) * 8 - 1)));

            inp_len &= mask;