Commit ca89174b authored by Richard Levitte's avatar Richard Levitte
Browse files

ASN.1 DER: Make INT32 / INT64 types read badly encoded LONG zeroes 



The deprecated ASN.1 type LONG / ZLONG (incorrectly) produced zero
length INTEGER encoding for zeroes.  For the sake of backward
compatibility, we allow those to be read without fault when using the
replacement types INT32 / UINT32 / INT64 / UINT64.

Fixes #7134

Reviewed-by: default avatarTim Hudson <tjh@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/7144)
parent c2278c8b

crypto/asn1/x_int64.c

+24 −0
Original line number Diff line number Diff line
@@ -81,6 +81,16 @@ static int uint64_c2i(ASN1_VALUE **pval, const unsigned char *cont, int len, 
        return 0;



    cp = (char *)*pval;



    /*

     * Strictly speaking, zero length is malformed.  However, long_c2i

     * (x_long.c) encodes 0 as a zero length INTEGER (wrongly, of course),

     * so for the sake of backward compatibility, we still decode zero

     * length INTEGERs as the number zero.

     */

    if (len == 0)

        goto long_compat;



    if (!c2i_uint64_int(&utmp, &neg, &cont, len))

        return 0;

    if ((it->size & INTxx_FLAG_SIGNED) == 0 && neg) {
@@ -95,6 +105,8 @@ static int uint64_c2i(ASN1_VALUE **pval, const unsigned char *cont, int len, 
    if (neg)

        /* c2i_uint64_int() returns positive values */

        utmp = 0 - utmp;



 long_compat:

    memcpy(cp, &utmp, sizeof(utmp));

    return 1;

}
@@ -172,6 +184,16 @@ static int uint32_c2i(ASN1_VALUE **pval, const unsigned char *cont, int len, 
        return 0;



    cp = (char *)*pval;



    /*

     * Strictly speaking, zero length is malformed.  However, long_c2i

     * (x_long.c) encodes 0 as a zero length INTEGER (wrongly, of course),

     * so for the sake of backward compatibility, we still decode zero

     * length INTEGERs as the number zero.

     */

    if (len == 0)

        goto long_compat;



    if (!c2i_uint64_int(&utmp, &neg, &cont, len))

        return 0;

    if ((it->size & INTxx_FLAG_SIGNED) == 0 && neg) {
@@ -191,6 +213,8 @@ static int uint32_c2i(ASN1_VALUE **pval, const unsigned char *cont, int len, 
            return 0;

        }

    }



 long_compat:

    utmp2 = (uint32_t)utmp;

    memcpy(cp, &utmp2, sizeof(utmp2));

    return 1;