Commit 03a5e5ae authored by Patrick Steuer's avatar Patrick Steuer Committed by Rich Salz
Browse files

Fix undefined behavior in s390x aes-gcm/ccm 



Reviewed-by: default avatarRich Salz <rsalz@openssl.org>
Reviewed-by: default avatarAndy Polyakov <appro@openssl.org>
parent 71883868

crypto/evp/e_aes.c

+21 −19
Original line number Diff line number Diff line
@@ -144,6 +144,22 @@ void AES_xts_decrypt(const unsigned char *inp, unsigned char *out, size_t len, 
                     const unsigned char iv[16]);

#endif



/* increment counter (64-bit int) by 1 */

static void ctr64_inc(unsigned char *counter)

{

    int n = 8;

    unsigned char c;



    do {

        --n;

        c = counter[n];

        ++c;

        counter[n] = c;

        if (c)

            return;

    } while (n);

}



#if defined(OPENSSL_CPUID_OBJ) && (defined(__powerpc__) || defined(__ppc__) || defined(_ARCH_PPC))

# include "ppc_arch.h"

# ifdef VPAES_ASM
@@ -1654,7 +1670,7 @@ static int s390x_aes_gcm_ctrl(EVP_CIPHER_CTX *c, int type, int arg, void *ptr) 
         * Invocation field will be at least 8 bytes in size and so no need

         * to check wrap around or increment more than last 8 bytes.

         */

        (*(unsigned long long *)(gctx->iv + gctx->ivlen - 8))++;

        ctr64_inc(gctx->iv + gctx->ivlen - 8);

        gctx->iv_set = 1;

        return 1;
@@ -2291,7 +2307,7 @@ static int s390x_aes_ccm_ctrl(EVP_CIPHER_CTX *c, int type, int arg, void *ptr) 
        memcpy(buf, ptr, arg);

        cctx->aes.ccm.tls_aad_len = arg;



        len = *(uint16_t *)(buf + arg - 2);

        len = buf[arg - 2] << 8 | buf[arg - 1];

        if (len < EVP_CCM_TLS_EXPLICIT_IV_LEN)

            return 0;
@@ -2307,7 +2323,9 @@ static int s390x_aes_ccm_ctrl(EVP_CIPHER_CTX *c, int type, int arg, void *ptr) 
            len -= cctx->aes.ccm.m;

        }



        *(uint16_t *)(buf + arg - 2) = len;

        buf[arg - 2] = len >> 8;

        buf[arg - 1] = len & 0xff;



        /* Extra padding: tag appended to record. */

        return cctx->aes.ccm.m;
@@ -2791,22 +2809,6 @@ static int aes_gcm_cleanup(EVP_CIPHER_CTX *c) 
    return 1;

}



/* increment counter (64-bit int) by 1 */

static void ctr64_inc(unsigned char *counter)

{

    int n = 8;

    unsigned char c;



    do {

        --n;

        c = counter[n];

        ++c;

        counter[n] = c;

        if (c)

            return;

    } while (n);

}



static int aes_gcm_ctrl(EVP_CIPHER_CTX *c, int type, int arg, void *ptr)

{

    EVP_AES_GCM_CTX *gctx = EVP_C_DATA(EVP_AES_GCM_CTX,c);