Commit 429223d1 authored by Richard Levitte's avatar Richard Levitte
Browse files

Fix x_int64.c 



Clearing a misunderstanding.  The routines c2i_uint64_int() and
i2c_uint64_int() expect to receive that internal values are absolute
and with a separate sign flag, and the x_int64.c code handles values
that aren't absolute and have the sign bit embedded.  We therefore
need to convert between absolute and non-absolute values for the
encoding of negative values to be correct.

[extended tests]

Reviewed-by: default avatarAndy Polyakov <appro@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/3160)
parent afd7cae2

crypto/asn1/x_int64.c

+31 −8
Original line number Diff line number Diff line
@@ -52,8 +52,11 @@ static int uint64_i2c(ASN1_VALUE **pval, unsigned char *cont, int *putype, 
        && utmp == 0)

        return -1;

    if ((it->size & INTxx_FLAG_SIGNED) == INTxx_FLAG_SIGNED

        && (int64_t)utmp < 0)

        && (int64_t)utmp < 0) {

        /* i2c_uint64_int() assumes positive values */

        utmp = 0 - utmp;

        neg = 1;

    }



    return i2c_uint64_int(cont, utmp, neg);

}
@@ -76,6 +79,9 @@ static int uint64_c2i(ASN1_VALUE **pval, const unsigned char *cont, int len, 
        ASN1err(ASN1_F_UINT64_C2I, ASN1_R_TOO_LARGE);

        return 0;

    }

    if (neg)

        /* c2i_uint64_int() returns positive values */

        utmp = 0 - utmp;

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

    return 1;

}
@@ -116,12 +122,22 @@ static int uint32_i2c(ASN1_VALUE **pval, unsigned char *cont, int *putype, 
        && utmp == 0)

        return -1;

    if ((it->size & INTxx_FLAG_SIGNED) == INTxx_FLAG_SIGNED

        && (int32_t)utmp < 0)

        && (int32_t)utmp < 0) {

        /* i2c_uint64_int() assumes positive values */

        utmp = 0 - utmp;

        neg = 1;

    }



    return i2c_uint64_int(cont, (uint64_t)utmp, neg);

}



/*

 * Absolute value of INT32_MIN: we can't just use -INT32_MIN as it produces

 * overflow warnings.

 */



#define ABS_INT32_MIN ((uint32_t)INT32_MAX + 1)



static int uint32_c2i(ASN1_VALUE **pval, const unsigned char *cont, int len,

                    int utype, char *free_cont, const ASN1_ITEM *it)

{
@@ -136,13 +152,20 @@ static int uint32_c2i(ASN1_VALUE **pval, const unsigned char *cont, int len, 
        ASN1err(ASN1_F_UINT32_C2I, ASN1_R_ILLEGAL_NEGATIVE_VALUE);

        return 0;

    }

    utmp2 = (uint32_t)utmp;

    if (utmp != utmp2

        || ((it->size & INTxx_FLAG_SIGNED) == INTxx_FLAG_SIGNED

            && !neg && utmp2 > INT32_MAX)) {

    if (neg) {

        if (utmp > ABS_INT32_MIN) {

            ASN1err(ASN1_F_UINT32_C2I, ASN1_R_TOO_SMALL);

            return 0;

        }

        utmp = 0 - utmp;

    } else {

        if (((it->size & INTxx_FLAG_SIGNED) != 0 && utmp > INT32_MAX)

            || ((it->size & INTxx_FLAG_SIGNED) == 0 && utmp > UINT32_MAX)) {

            ASN1err(ASN1_F_UINT32_C2I, ASN1_R_TOO_LARGE);

            return 0;

        }

    }

    utmp2 = (uint32_t)utmp;

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

    return 1;

}