Avoid having an unsigned integer decrement below zero.

    return (0x80);

}

/*

 * Decode a length field.

 * The short form is a single byte defining a length 0 - 127.

 * The long form is a byte 0 - 127 with the top bit set and this indicates

 * the number of following octets that contain the length.  These octets

 * are stored most significant digit first.

 */

static int asn1_get_length(const unsigned char **pp, int *inf, long *rl,

                           long max)

{

    const unsigned char *p = *pp;

    unsigned long ret = 0;

    unsigned long i;

    int i;

    if (max-- < 1)

        return 0;

    if (*p == 0x80) {

        *inf = 1;

        ret = 0;

        p++;

    } else {

        *inf = 0;

        i = *p & 0x7f;

        if (*(p++) & 0x80) {

            if (max < (long)i + 1)

        if (*p++ & 0x80) {

            if (max < i + 1)

                return 0;

            /* Skip leading zeroes */

            while (i && *p == 0) {

            while (i > 0 && *p == 0) {

                p++;

                i--;

            }

            if (i > sizeof(long))

            if (i > (int)sizeof(long))

                return 0;

            while (i-- > 0) {

                ret <<= 8L;

                ret |= *(p++);

            while (i > 0) {

                ret <<= 8;

                ret |= *p++;

                i--;

            }

            if (ret > LONG_MAX)

                return 0;

        } else

            ret = i;

    }

    if (ret > LONG_MAX)

        return 0;

    *pp = p;

    *rl = (long)ret;

    return 1;