crypto/ec/ecdsa_ossl.c:437: error: BUFFER_OVERRUN_L3
  Offset: [1, +oo] Size: [0, 8388607] by call to `BN_mod_mul`.
Showing all 22 steps of the trace


crypto/ec/ecdsa_ossl.c:361:1: Parameter `eckey->group->order->top`
359.   }
360.   
361. > int ossl_ecdsa_verify_sig(const unsigned char *dgst, int dgst_len,
362.                             const ECDSA_SIG *sig, EC_KEY *eckey)
363.   {

crypto/ec/ecdsa_ossl.c:421:9: Call
419.       }
420.       /* digest -> m */
421.       i = BN_num_bits(order);
               ^
422.       /*
423.        * Need to truncate digest if it is too long: first truncate whole bytes.

crypto/bn/bn_lib.c:166:9: Call
  164.       bn_check_top(a);
  165.   
  166.       if (BN_is_zero(a))
                 ^
  167.           return 0;
  168.       return ((i * BN_BITS2) + BN_num_bits_word(a->d[i]));

crypto/bn/bn_lib.c:844:1: Parameter `a->top`
    842.   }
    843.   
    844. > int BN_is_zero(const BIGNUM *a)
    845.   {
    846.       return a->top == 0;

crypto/ec/ecdsa_ossl.c:437:10: Call
435.       }
436.       /* u1 = m * tmp mod order */
437.       if (!BN_mod_mul(u1, m, u2, order, ctx)) {
                ^
438.           ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, ERR_R_BN_LIB);
439.           goto err;

crypto/bn/bn_mod.c:73:1: Parameter `m->top`
  71.   
  72.   /* slow but works */
  73. > int BN_mod_mul(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, const BIGNUM *m,
  74.                  BN_CTX *ctx)
  75.   {

crypto/bn/bn_mod.c:93:10: Call
  91.               goto err;
  92.       }
  93.       if (!BN_nnmod(r, t, m, ctx))
                 ^
  94.           goto err;
  95.       bn_check_top(r);

crypto/bn/bn_mod.c:13:1: Parameter `d->top`
    11.   #include "bn_lcl.h"
    12.   
    13. > int BN_nnmod(BIGNUM *r, const BIGNUM *m, const BIGNUM *d, BN_CTX *ctx)
    14.   {
    15.       /*

crypto/bn/bn_mod.c:20:11: Call
    18.        */
    19.   
    20.       if (!(BN_mod(r, m, d, ctx)))
                    ^
    21.           return 0;
    22.       if (!r->neg)

crypto/bn/bn_div.c:199:31: Call
      197.   
      198.       /* First we normalise the numbers */
      199.       norm_shift = BN_BITS2 - ((BN_num_bits(divisor)) % BN_BITS2);
                                           ^
      200.       if (!(BN_lshift(sdiv, divisor, norm_shift)))
      201.           goto err;

crypto/bn/bn_lib.c:167:9: Assignment
        165.   
        166.       if (BN_is_zero(a))
        167.           return 0;
                       ^
        168.       return ((i * BN_BITS2) + BN_num_bits_word(a->d[i]));
        169.   }

crypto/bn/bn_div.c:199:5: Assignment
      197.   
      198.       /* First we normalise the numbers */
      199.       norm_shift = BN_BITS2 - ((BN_num_bits(divisor)) % BN_BITS2);
                 ^
      200.       if (!(BN_lshift(sdiv, divisor, norm_shift)))
      201.           goto err;

crypto/bn/bn_div.c:200:11: Call
      198.       /* First we normalise the numbers */
      199.       norm_shift = BN_BITS2 - ((BN_num_bits(divisor)) % BN_BITS2);
      200.       if (!(BN_lshift(sdiv, divisor, norm_shift)))
                       ^
      201.           goto err;
      202.       sdiv->neg = 0;

crypto/bn/bn_shift.c:83:1: <Offset trace>
81.   }
82.   
83. > int BN_lshift(BIGNUM *r, const BIGNUM *a, int n)
84.   {
85.       int i, nw, lb, rb;

crypto/bn/bn_shift.c:83:1: Parameter `n`
        81.   }
        82.   
        83. > int BN_lshift(BIGNUM *r, const BIGNUM *a, int n)
        84.   {
        85.       int i, nw, lb, rb;

crypto/bn/bn_shift.c:97:5: Assignment
        95.       }
        96.   
        97.       nw = n / BN_BITS2;
                   ^
        98.       if (bn_wexpand(r, a->top + nw + 1) == NULL)
        99.           return 0;

crypto/bn/bn_shift.c:83:1: <Length trace>
81.   }
82.   
83. > int BN_lshift(BIGNUM *r, const BIGNUM *a, int n)
84.   {
85.       int i, nw, lb, rb;

crypto/bn/bn_shift.c:83:1: Parameter `*r->d`
        81.   }
        82.   
        83. > int BN_lshift(BIGNUM *r, const BIGNUM *a, int n)
        84.   {
        85.       int i, nw, lb, rb;

crypto/bn/bn_shift.c:98:9: Call
        96.   
        97.       nw = n / BN_BITS2;
        98.       if (bn_wexpand(r, a->top + nw + 1) == NULL)
                       ^
        99.           return 0;
        100.       r->neg = a->neg;

crypto/bn/bn_lib.c:940:1: Parameter `*a->d`
          938.   }
          939.   
          940. > BIGNUM *bn_wexpand(BIGNUM *a, int words)
          941.   {
          942.       return (words <= a->dmax) ? a : bn_expand2(a, words);

crypto/bn/bn_shift.c:104:5: Assignment
        102.       rb = BN_BITS2 - lb;
        103.       f = a->d;
        104.       t = r->d;
                   ^
        105.       t[a->top + nw] = 0;
        106.       if (lb == 0)

crypto/bn/bn_shift.c:112:13: Array access: Offset: [1, +oo] Size: [0, 8388607] by call to `BN_mod_mul` 
        110.           for (i = a->top - 1; i >= 0; i--) {
        111.               l = f[i];
        112.               t[nw + i + 1] |= (l >> rb) & BN_MASK2;
                           ^
        113.               t[nw + i] = (l << lb) & BN_MASK2;
        114.           }

int BN_lshift(BIGNUM *r, const BIGNUM *a, int n)
{
    int i, nw, lb, rb;
    BN_ULONG *t, *f;
    BN_ULONG l;
    bn_check_top(r);
    bn_check_top(a);
    if (n < 0) {
        BNerr(BN_F_BN_LSHIFT, BN_R_INVALID_SHIFT);
        return 0;
    }
    nw = n / BN_BITS2;
    if (bn_wexpand(r, a->top + nw + 1) == NULL)
        return 0;
    r->neg = a->neg;
    lb = n % BN_BITS2;
    rb = BN_BITS2 - lb;
    f = a->d;
    t = r->d;
    t[a->top + nw] = 0;
    if (lb == 0)
        for (i = a->top - 1; i >= 0; i--)
            t[nw + i] = f[i];
    else
        for (i = a->top - 1; i >= 0; i--) {
            l = f[i];
            t[nw + i + 1] |= (l >> rb) & BN_MASK2;
            t[nw + i] = (l << lb) & BN_MASK2;
        }
    memset(t, 0, sizeof(*t) * nw);
    r->top = a->top + nw + 1;
    bn_correct_top(r);
    bn_check_top(r);
    return 1;
}
['int ossl_ecdsa_verify_sig(const unsigned char *dgst, int dgst_len,\n                          const ECDSA_SIG *sig, EC_KEY *eckey)\n{\n    int ret = -1, i;\n    BN_CTX *ctx;\n    const BIGNUM *order;\n    BIGNUM *u1, *u2, *m, *X;\n    EC_POINT *point = NULL;\n    const EC_GROUP *group;\n    const EC_POINT *pub_key;\n    if (eckey == NULL || (group = EC_KEY_get0_group(eckey)) == NULL ||\n        (pub_key = EC_KEY_get0_public_key(eckey)) == NULL || sig == NULL) {\n        ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, EC_R_MISSING_PARAMETERS);\n        return -1;\n    }\n    if (!EC_KEY_can_sign(eckey)) {\n        ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, EC_R_CURVE_DOES_NOT_SUPPORT_SIGNING);\n        return -1;\n    }\n    ctx = BN_CTX_new();\n    if (ctx == NULL) {\n        ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, ERR_R_MALLOC_FAILURE);\n        return -1;\n    }\n    BN_CTX_start(ctx);\n    u1 = BN_CTX_get(ctx);\n    u2 = BN_CTX_get(ctx);\n    m = BN_CTX_get(ctx);\n    X = BN_CTX_get(ctx);\n    if (X == NULL) {\n        ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, ERR_R_BN_LIB);\n        goto err;\n    }\n    order = EC_GROUP_get0_order(group);\n    if (order == NULL) {\n        ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, ERR_R_EC_LIB);\n        goto err;\n    }\n    if (BN_is_zero(sig->r) || BN_is_negative(sig->r) ||\n        BN_ucmp(sig->r, order) >= 0 || BN_is_zero(sig->s) ||\n        BN_is_negative(sig->s) || BN_ucmp(sig->s, order) >= 0) {\n        ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, EC_R_BAD_SIGNATURE);\n        ret = 0;\n        goto err;\n    }\n    if (EC_GROUP_do_inverse_ord(group, u2, sig->s, ctx) == 0) {\n        if (!BN_mod_inverse(u2, sig->s, order, ctx)) {\n            ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, ERR_R_BN_LIB);\n            goto err;\n        }\n    }\n    i = BN_num_bits(order);\n    if (8 * dgst_len > i)\n        dgst_len = (i + 7) / 8;\n    if (!BN_bin2bn(dgst, dgst_len, m)) {\n        ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, ERR_R_BN_LIB);\n        goto err;\n    }\n    if ((8 * dgst_len > i) && !BN_rshift(m, m, 8 - (i & 0x7))) {\n        ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, ERR_R_BN_LIB);\n        goto err;\n    }\n    if (!BN_mod_mul(u1, m, u2, order, ctx)) {\n        ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, ERR_R_BN_LIB);\n        goto err;\n    }\n    if (!BN_mod_mul(u2, sig->r, u2, order, ctx)) {\n        ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, ERR_R_BN_LIB);\n        goto err;\n    }\n    if ((point = EC_POINT_new(group)) == NULL) {\n        ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, ERR_R_MALLOC_FAILURE);\n        goto err;\n    }\n    if (!EC_POINT_mul(group, point, u1, pub_key, u2, ctx)) {\n        ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, ERR_R_EC_LIB);\n        goto err;\n    }\n    if (EC_METHOD_get_field_type(EC_GROUP_method_of(group)) ==\n        NID_X9_62_prime_field) {\n        if (!EC_POINT_get_affine_coordinates_GFp(group, point, X, NULL, ctx)) {\n            ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, ERR_R_EC_LIB);\n            goto err;\n        }\n    }\n#ifndef OPENSSL_NO_EC2M\n    else {\n        if (!EC_POINT_get_affine_coordinates_GF2m(group, point, X, NULL, ctx)) {\n            ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, ERR_R_EC_LIB);\n            goto err;\n        }\n    }\n#endif\n    if (!BN_nnmod(u1, X, order, ctx)) {\n        ECerr(EC_F_OSSL_ECDSA_VERIFY_SIG, ERR_R_BN_LIB);\n        goto err;\n    }\n    ret = (BN_ucmp(u1, sig->r) == 0);\n err:\n    BN_CTX_end(ctx);\n    BN_CTX_free(ctx);\n    EC_POINT_free(point);\n    return ret;\n}', 'int BN_num_bits(const BIGNUM *a)\n{\n    int i = a->top - 1;\n    bn_check_top(a);\n    if (BN_is_zero(a))\n        return 0;\n    return ((i * BN_BITS2) + BN_num_bits_word(a->d[i]));\n}', 'int BN_is_zero(const BIGNUM *a)\n{\n    return a->top == 0;\n}', 'int BN_mod_mul(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, const BIGNUM *m,\n               BN_CTX *ctx)\n{\n    BIGNUM *t;\n    int ret = 0;\n    bn_check_top(a);\n    bn_check_top(b);\n    bn_check_top(m);\n    BN_CTX_start(ctx);\n    if ((t = BN_CTX_get(ctx)) == NULL)\n        goto err;\n    if (a == b) {\n        if (!BN_sqr(t, a, ctx))\n            goto err;\n    } else {\n        if (!BN_mul(t, a, b, ctx))\n            goto err;\n    }\n    if (!BN_nnmod(r, t, m, ctx))\n        goto err;\n    bn_check_top(r);\n    ret = 1;\n err:\n    BN_CTX_end(ctx);\n    return ret;\n}', 'int BN_nnmod(BIGNUM *r, const BIGNUM *m, const BIGNUM *d, BN_CTX *ctx)\n{\n    if (!(BN_mod(r, m, d, ctx)))\n        return 0;\n    if (!r->neg)\n        return 1;\n    return (d->neg ? BN_sub : BN_add) (r, r, d);\n}', 'int BN_div(BIGNUM *dv, BIGNUM *rm, const BIGNUM *num, const BIGNUM *divisor,\n           BN_CTX *ctx)\n{\n    int norm_shift, i, loop;\n    BIGNUM *tmp, wnum, *snum, *sdiv, *res;\n    BN_ULONG *resp, *wnump;\n    BN_ULONG d0, d1;\n    int num_n, div_n;\n    int no_branch = 0;\n    if ((num->top > 0 && num->d[num->top - 1] == 0) ||\n        (divisor->top > 0 && divisor->d[divisor->top - 1] == 0)) {\n        BNerr(BN_F_BN_DIV, BN_R_NOT_INITIALIZED);\n        return 0;\n    }\n    bn_check_top(num);\n    bn_check_top(divisor);\n    if ((BN_get_flags(num, BN_FLG_CONSTTIME) != 0)\n        || (BN_get_flags(divisor, BN_FLG_CONSTTIME) != 0)) {\n        no_branch = 1;\n    }\n    bn_check_top(dv);\n    bn_check_top(rm);\n    if (BN_is_zero(divisor)) {\n        BNerr(BN_F_BN_DIV, BN_R_DIV_BY_ZERO);\n        return 0;\n    }\n    if (!no_branch && BN_ucmp(num, divisor) < 0) {\n        if (rm != NULL) {\n            if (BN_copy(rm, num) == NULL)\n                return 0;\n        }\n        if (dv != NULL)\n            BN_zero(dv);\n        return 1;\n    }\n    BN_CTX_start(ctx);\n    res = (dv == NULL) ? BN_CTX_get(ctx) : dv;\n    tmp = BN_CTX_get(ctx);\n    snum = BN_CTX_get(ctx);\n    sdiv = BN_CTX_get(ctx);\n    if (sdiv == NULL)\n        goto err;\n    norm_shift = BN_BITS2 - ((BN_num_bits(divisor)) % BN_BITS2);\n    if (!(BN_lshift(sdiv, divisor, norm_shift)))\n        goto err;\n    sdiv->neg = 0;\n    norm_shift += BN_BITS2;\n    if (!(BN_lshift(snum, num, norm_shift)))\n        goto err;\n    snum->neg = 0;\n    if (no_branch) {\n        if (snum->top <= sdiv->top + 1) {\n            if (bn_wexpand(snum, sdiv->top + 2) == NULL)\n                goto err;\n            for (i = snum->top; i < sdiv->top + 2; i++)\n                snum->d[i] = 0;\n            snum->top = sdiv->top + 2;\n        } else {\n            if (bn_wexpand(snum, snum->top + 1) == NULL)\n                goto err;\n            snum->d[snum->top] = 0;\n            snum->top++;\n        }\n    }\n    div_n = sdiv->top;\n    num_n = snum->top;\n    loop = num_n - div_n;\n    wnum.neg = 0;\n    wnum.d = &(snum->d[loop]);\n    wnum.top = div_n;\n    wnum.dmax = snum->dmax - loop;\n    d0 = sdiv->d[div_n - 1];\n    d1 = (div_n == 1) ? 0 : sdiv->d[div_n - 2];\n    wnump = &(snum->d[num_n - 1]);\n    if (!bn_wexpand(res, (loop + 1)))\n        goto err;\n    res->neg = (num->neg ^ divisor->neg);\n    res->top = loop - no_branch;\n    resp = &(res->d[loop - 1]);\n    if (!bn_wexpand(tmp, (div_n + 1)))\n        goto err;\n    if (!no_branch) {\n        if (BN_ucmp(&wnum, sdiv) >= 0) {\n            bn_clear_top2max(&wnum);\n            bn_sub_words(wnum.d, wnum.d, sdiv->d, div_n);\n            *resp = 1;\n        } else\n            res->top--;\n    }\n    resp++;\n    if (res->top == 0)\n        res->neg = 0;\n    else\n        resp--;\n    for (i = 0; i < loop - 1; i++, wnump--) {\n        BN_ULONG q, l0;\n# if defined(BN_DIV3W) && !defined(OPENSSL_NO_ASM)\n        BN_ULONG bn_div_3_words(BN_ULONG *, BN_ULONG, BN_ULONG);\n        q = bn_div_3_words(wnump, d1, d0);\n# else\n        BN_ULONG n0, n1, rem = 0;\n        n0 = wnump[0];\n        n1 = wnump[-1];\n        if (n0 == d0)\n            q = BN_MASK2;\n        else {\n#  ifdef BN_LLONG\n            BN_ULLONG t2;\n#   if defined(BN_LLONG) && defined(BN_DIV2W) && !defined(bn_div_words)\n            q = (BN_ULONG)(((((BN_ULLONG) n0) << BN_BITS2) | n1) / d0);\n#   else\n            q = bn_div_words(n0, n1, d0);\n#   endif\n#   ifndef REMAINDER_IS_ALREADY_CALCULATED\n            rem = (n1 - q * d0) & BN_MASK2;\n#   endif\n            t2 = (BN_ULLONG) d1 *q;\n            for (;;) {\n                if (t2 <= ((((BN_ULLONG) rem) << BN_BITS2) | wnump[-2]))\n                    break;\n                q--;\n                rem += d0;\n                if (rem < d0)\n                    break;\n                t2 -= d1;\n            }\n#  else\n            BN_ULONG t2l, t2h;\n            q = bn_div_words(n0, n1, d0);\n#   ifndef REMAINDER_IS_ALREADY_CALCULATED\n            rem = (n1 - q * d0) & BN_MASK2;\n#   endif\n#   if defined(BN_UMULT_LOHI)\n            BN_UMULT_LOHI(t2l, t2h, d1, q);\n#   elif defined(BN_UMULT_HIGH)\n            t2l = d1 * q;\n            t2h = BN_UMULT_HIGH(d1, q);\n#   else\n            {\n                BN_ULONG ql, qh;\n                t2l = LBITS(d1);\n                t2h = HBITS(d1);\n                ql = LBITS(q);\n                qh = HBITS(q);\n                mul64(t2l, t2h, ql, qh);\n            }\n#   endif\n            for (;;) {\n                if ((t2h < rem) || ((t2h == rem) && (t2l <= wnump[-2])))\n                    break;\n                q--;\n                rem += d0;\n                if (rem < d0)\n                    break;\n                if (t2l < d1)\n                    t2h--;\n                t2l -= d1;\n            }\n#  endif\n        }\n# endif\n        l0 = bn_mul_words(tmp->d, sdiv->d, div_n, q);\n        tmp->d[div_n] = l0;\n        wnum.d--;\n        if (bn_sub_words(wnum.d, wnum.d, tmp->d, div_n + 1)) {\n            q--;\n            if (bn_add_words(wnum.d, wnum.d, sdiv->d, div_n))\n                (*wnump)++;\n        }\n        resp--;\n        *resp = q;\n    }\n    bn_correct_top(snum);\n    if (rm != NULL) {\n        int neg = num->neg;\n        BN_rshift(rm, snum, norm_shift);\n        if (!BN_is_zero(rm))\n            rm->neg = neg;\n        bn_check_top(rm);\n    }\n    if (no_branch)\n        bn_correct_top(res);\n    BN_CTX_end(ctx);\n    return 1;\n err:\n    bn_check_top(rm);\n    BN_CTX_end(ctx);\n    return 0;\n}', 'int BN_lshift(BIGNUM *r, const BIGNUM *a, int n)\n{\n    int i, nw, lb, rb;\n    BN_ULONG *t, *f;\n    BN_ULONG l;\n    bn_check_top(r);\n    bn_check_top(a);\n    if (n < 0) {\n        BNerr(BN_F_BN_LSHIFT, BN_R_INVALID_SHIFT);\n        return 0;\n    }\n    nw = n / BN_BITS2;\n    if (bn_wexpand(r, a->top + nw + 1) == NULL)\n        return 0;\n    r->neg = a->neg;\n    lb = n % BN_BITS2;\n    rb = BN_BITS2 - lb;\n    f = a->d;\n    t = r->d;\n    t[a->top + nw] = 0;\n    if (lb == 0)\n        for (i = a->top - 1; i >= 0; i--)\n            t[nw + i] = f[i];\n    else\n        for (i = a->top - 1; i >= 0; i--) {\n            l = f[i];\n            t[nw + i + 1] |= (l >> rb) & BN_MASK2;\n            t[nw + i] = (l << lb) & BN_MASK2;\n        }\n    memset(t, 0, sizeof(*t) * nw);\n    r->top = a->top + nw + 1;\n    bn_correct_top(r);\n    bn_check_top(r);\n    return 1;\n}', 'BIGNUM *bn_wexpand(BIGNUM *a, int words)\n{\n    return (words <= a->dmax) ? a : bn_expand2(a, words);\n}']