Commit 2432e129 authored by Nicola Tuveri's avatar Nicola Tuveri
Browse files

Uniform BN_bn2binpad() and BN_bn2lebinpad() implementations 



Reviewed-by: default avatarMatt Caswell <matt@openssl.org>
Reviewed-by: default avatarBernd Edlinger <bernd.edlinger@hotmail.de>
(Merged from https://github.com/openssl/openssl/pull/9511)

(cherry picked from commit 1b338abe3abb8c73f004c34d4b8a9272b89dfd5d)
parent b9a380f7

crypto/bn/bn_lib.c

+17 −20
Original line number Diff line number Diff line
@@ -458,8 +458,11 @@ BIGNUM *BN_bin2bn(const unsigned char *s, int len, BIGNUM *ret) 
    return ret;

}



typedef enum {big, little} endianess_t;



/* ignore negative */

static int bn2binpad(const BIGNUM *a, unsigned char *to, int tolen)

static

int bn2binpad(const BIGNUM *a, unsigned char *to, int tolen, endianess_t endianess)

{

    int n;

    size_t i, lasti, j, atop, mask;
@@ -491,10 +494,17 @@ static int bn2binpad(const BIGNUM *a, unsigned char *to, int tolen) 


    lasti = atop - 1;

    atop = a->top * BN_BYTES;

    for (i = 0, j = 0, to += tolen; j < (size_t)tolen; j++) {

    if (endianess == big)

        to += tolen; /* start from the end of the buffer */

    for (i = 0, j = 0; j < (size_t)tolen; j++) {

        unsigned char val;

        l = a->d[i / BN_BYTES];

        mask = 0 - ((j - atop) >> (8 * sizeof(i) - 1));

        *--to = (unsigned char)(l >> (8 * (i % BN_BYTES)) & mask);

        val = (unsigned char)(l >> (8 * (i % BN_BYTES)) & mask);

        if (endianess == big)

            *--to = val;

        else

            *to++ = val;

        i += (i - lasti) >> (8 * sizeof(i) - 1); /* stay on last limb */

    }
@@ -505,12 +515,12 @@ int BN_bn2binpad(const BIGNUM *a, unsigned char *to, int tolen) 
{

    if (tolen < 0)

        return -1;

    return bn2binpad(a, to, tolen);

    return bn2binpad(a, to, tolen, big);

}



int BN_bn2bin(const BIGNUM *a, unsigned char *to)

{

    return bn2binpad(a, to, -1);

    return bn2binpad(a, to, -1, big);

}



BIGNUM *BN_lebin2bn(const unsigned char *s, int len, BIGNUM *ret)
@@ -562,22 +572,9 @@ BIGNUM *BN_lebin2bn(const unsigned char *s, int len, BIGNUM *ret) 


int BN_bn2lebinpad(const BIGNUM *a, unsigned char *to, int tolen)

{

    int i;

    BN_ULONG l;

    bn_check_top(a);

    i = BN_num_bytes(a);

    if (tolen < i)

    if (tolen < 0)

        return -1;

    /* Add trailing zeroes if necessary */

    if (tolen > i)

        memset(to + i, 0, tolen - i);

    to += i;

    while (i--) {

        l = a->d[i / BN_BYTES];

        to--;

        *to = (unsigned char)(l >> (8 * (i % BN_BYTES))) & 0xff;

    }

    return tolen;

    return bn2binpad(a, to, tolen, little);

}



int BN_ucmp(const BIGNUM *a, const BIGNUM *b)