void bn_sqr_normal(BN_ULONG *r, const BN_ULONG *a, int n, BN_ULONG *tmp)
{
    int i, j, max;
    const BN_ULONG *ap;
    BN_ULONG *rp;
    max = n * 2;
    ap = a;
    rp = r;
    rp[0] = rp[max - 1] = 0;
    rp++;
    j = n;
    if (--j > 0) {
        ap++;
        rp[j] = bn_mul_words(rp, ap, j, ap[-1]);
        rp += 2;
    }
    for (i = n - 2; i > 0; i--) {
        j--;
        ap++;
        rp[j] = bn_mul_add_words(rp, ap, j, ap[-1]);
        rp += 2;
    }
    bn_add_words(r, r, r, max);
    bn_sqr_words(tmp, a, n);
    bn_add_words(r, r, tmp, max);
}
['int srp_generate_server_master_secret(SSL *s)\n{\n    BIGNUM *K = NULL, *u = NULL;\n    int ret = -1, tmp_len = 0;\n    unsigned char *tmp = NULL;\n    if (!SRP_Verify_A_mod_N(s->srp_ctx.A, s->srp_ctx.N))\n        goto err;\n    if ((u = SRP_Calc_u(s->srp_ctx.A, s->srp_ctx.B, s->srp_ctx.N)) == NULL)\n        goto err;\n    if ((K = SRP_Calc_server_key(s->srp_ctx.A, s->srp_ctx.v, u, s->srp_ctx.b,\n                                 s->srp_ctx.N)) == NULL)\n        goto err;\n    tmp_len = BN_num_bytes(K);\n    if ((tmp = OPENSSL_malloc(tmp_len)) == NULL)\n        goto err;\n    BN_bn2bin(K, tmp);\n    ret = ssl_generate_master_secret(s, tmp, tmp_len, 1);\n err:\n    BN_clear_free(K);\n    BN_clear_free(u);\n    return ret;\n}', 'int SRP_Verify_A_mod_N(const BIGNUM *A, const BIGNUM *N)\n{\n    return SRP_Verify_B_mod_N(A, N);\n}', 'int SRP_Verify_B_mod_N(const BIGNUM *B, const BIGNUM *N)\n{\n    BIGNUM *r;\n    BN_CTX *bn_ctx;\n    int ret = 0;\n    if (B == NULL || N == NULL || (bn_ctx = BN_CTX_new()) == NULL)\n        return 0;\n    if ((r = BN_new()) == NULL)\n        goto err;\n    if (!BN_nnmod(r, B, N, bn_ctx))\n        goto err;\n    ret = !BN_is_zero(r);\n err:\n    BN_CTX_free(bn_ctx);\n    BN_free(r);\n    return ret;\n}', 'BIGNUM *SRP_Calc_u(const BIGNUM *A, const BIGNUM *B, const BIGNUM *N)\n{\n    BIGNUM *u = NULL;\n    unsigned char cu[SHA_DIGEST_LENGTH];\n    unsigned char *cAB = NULL;\n    EVP_MD_CTX *ctxt = NULL;\n    int longN;\n    if ((A == NULL) || (B == NULL) || (N == NULL))\n        return NULL;\n    if (BN_ucmp(A, N) >= 0 || BN_ucmp(B, N) >= 0)\n        return NULL;\n    longN = BN_num_bytes(N);\n    ctxt = EVP_MD_CTX_new();\n    if (ctxt == NULL)\n        return NULL;\n    if ((cAB = OPENSSL_malloc(2 * longN)) == NULL)\n        goto err;\n    memset(cAB, 0, longN);\n    EVP_DigestInit_ex(ctxt, EVP_sha1(), NULL);\n    EVP_DigestUpdate(ctxt, cAB + BN_bn2bin(A, cAB + longN), longN);\n    EVP_DigestUpdate(ctxt, cAB + BN_bn2bin(B, cAB + longN), longN);\n    OPENSSL_free(cAB);\n    EVP_DigestFinal_ex(ctxt, cu, NULL);\n    if ((u = BN_bin2bn(cu, sizeof(cu), NULL)) == NULL)\n        goto err;\n    if (BN_is_zero(u)) {\n        BN_free(u);\n        u = NULL;\n    }\n err:\n    EVP_MD_CTX_free(ctxt);\n    return u;\n}', 'BIGNUM *SRP_Calc_server_key(const BIGNUM *A, const BIGNUM *v, const BIGNUM *u,\n                            const BIGNUM *b, const BIGNUM *N)\n{\n    BIGNUM *tmp = NULL, *S = NULL;\n    BN_CTX *bn_ctx;\n    if (u == NULL || A == NULL || v == NULL || b == NULL || N == NULL)\n        return NULL;\n    if ((bn_ctx = BN_CTX_new()) == NULL || (tmp = BN_new()) == NULL)\n        goto err;\n    if (!BN_mod_exp(tmp, v, u, N, bn_ctx))\n        goto err;\n    if (!BN_mod_mul(tmp, A, tmp, N, bn_ctx))\n        goto err;\n    S = BN_new();\n    if (S != NULL && !BN_mod_exp(S, tmp, b, N, bn_ctx)) {\n        BN_free(S);\n        S = NULL;\n    }\n err:\n    BN_CTX_free(bn_ctx);\n    BN_clear_free(tmp);\n    return S;\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_sqr(BIGNUM *r, const BIGNUM *a, BN_CTX *ctx)\n{\n    int max, al;\n    int ret = 0;\n    BIGNUM *tmp, *rr;\n    bn_check_top(a);\n    al = a->top;\n    if (al <= 0) {\n        r->top = 0;\n        r->neg = 0;\n        return 1;\n    }\n    BN_CTX_start(ctx);\n    rr = (a != r) ? r : BN_CTX_get(ctx);\n    tmp = BN_CTX_get(ctx);\n    if (!rr || !tmp)\n        goto err;\n    max = 2 * al;\n    if (bn_wexpand(rr, max) == NULL)\n        goto err;\n    if (al == 4) {\n#ifndef BN_SQR_COMBA\n        BN_ULONG t[8];\n        bn_sqr_normal(rr->d, a->d, 4, t);\n#else\n        bn_sqr_comba4(rr->d, a->d);\n#endif\n    } else if (al == 8) {\n#ifndef BN_SQR_COMBA\n        BN_ULONG t[16];\n        bn_sqr_normal(rr->d, a->d, 8, t);\n#else\n        bn_sqr_comba8(rr->d, a->d);\n#endif\n    } else {\n#if defined(BN_RECURSION)\n        if (al < BN_SQR_RECURSIVE_SIZE_NORMAL) {\n            BN_ULONG t[BN_SQR_RECURSIVE_SIZE_NORMAL * 2];\n            bn_sqr_normal(rr->d, a->d, al, t);\n        } else {\n            int j, k;\n            j = BN_num_bits_word((BN_ULONG)al);\n            j = 1 << (j - 1);\n            k = j + j;\n            if (al == j) {\n                if (bn_wexpand(tmp, k * 2) == NULL)\n                    goto err;\n                bn_sqr_recursive(rr->d, a->d, al, tmp->d);\n            } else {\n                if (bn_wexpand(tmp, max) == NULL)\n                    goto err;\n                bn_sqr_normal(rr->d, a->d, al, tmp->d);\n            }\n        }\n#else\n        if (bn_wexpand(tmp, max) == NULL)\n            goto err;\n        bn_sqr_normal(rr->d, a->d, al, tmp->d);\n#endif\n    }\n    rr->neg = 0;\n    if (a->d[al - 1] == (a->d[al - 1] & BN_MASK2l))\n        rr->top = max - 1;\n    else\n        rr->top = max;\n    if (rr != r)\n        BN_copy(r, rr);\n    ret = 1;\n err:\n    bn_check_top(rr);\n    bn_check_top(tmp);\n    BN_CTX_end(ctx);\n    return (ret);\n}', 'void bn_sqr_normal(BN_ULONG *r, const BN_ULONG *a, int n, BN_ULONG *tmp)\n{\n    int i, j, max;\n    const BN_ULONG *ap;\n    BN_ULONG *rp;\n    max = n * 2;\n    ap = a;\n    rp = r;\n    rp[0] = rp[max - 1] = 0;\n    rp++;\n    j = n;\n    if (--j > 0) {\n        ap++;\n        rp[j] = bn_mul_words(rp, ap, j, ap[-1]);\n        rp += 2;\n    }\n    for (i = n - 2; i > 0; i--) {\n        j--;\n        ap++;\n        rp[j] = bn_mul_add_words(rp, ap, j, ap[-1]);\n        rp += 2;\n    }\n    bn_add_words(r, r, r, max);\n    bn_sqr_words(tmp, a, n);\n    bn_add_words(r, r, tmp, max);\n}']