crypto/rsa/rsa_gen.c:192: error: INTEGER_OVERFLOW_L2
  ([0, +oo] - 1):unsigned32 by call to `BN_mod_inverse`.
Showing all 22 steps of the trace


crypto/rsa/rsa_gen.c:91:5: Call
89.       if (ctx == NULL)
90.           goto err;
91.       BN_CTX_start(ctx);
          ^
92.       r0 = BN_CTX_get(ctx);
93.       r1 = BN_CTX_get(ctx);

crypto/bn/bn_ctx.c:181:1: Parameter `ctx->stack.depth`
  179.   }
  180.   
  181. > void BN_CTX_start(BN_CTX *ctx)
  182.   {
  183.       CTXDBG_ENTRY("BN_CTX_start", ctx);

crypto/rsa/rsa_gen.c:192:17: Call
190.               ERR_set_mark();
191.               BN_set_flags(r2, BN_FLG_CONSTTIME);
192.               if (BN_mod_inverse(r1, r2, rsa->e, ctx) != NULL) {
                       ^
193.                  /* GCD == 1 since inverse exists */
194.                   break;

crypto/bn/bn_gcd.c:124:1: Parameter `ctx->stack.depth`
  122.                                           BN_CTX *ctx);
  123.   
  124. > BIGNUM *BN_mod_inverse(BIGNUM *in,
  125.                          const BIGNUM *a, const BIGNUM *n, BN_CTX *ctx)
  126.   {

crypto/bn/bn_gcd.c:129:10: Call
  127.       BIGNUM *rv;
  128.       int noinv;
  129.       rv = int_bn_mod_inverse(in, a, n, ctx, &noinv);
                  ^
  130.       if (noinv)
  131.           BNerr(BN_F_BN_MOD_INVERSE, BN_R_NO_INVERSE);

crypto/bn/bn_gcd.c:135:1: Parameter `ctx->stack.depth`
    133.   }
    134.   
    135. > BIGNUM *int_bn_mod_inverse(BIGNUM *in,
    136.                              const BIGNUM *a, const BIGNUM *n, BN_CTX *ctx,
    137.                              int *pnoinv)

crypto/bn/bn_gcd.c:148:16: Call
    146.       if ((BN_get_flags(a, BN_FLG_CONSTTIME) != 0)
    147.           || (BN_get_flags(n, BN_FLG_CONSTTIME) != 0)) {
    148.           return BN_mod_inverse_no_branch(in, a, n, ctx);
                          ^
    149.       }
    150.   

crypto/bn/bn_gcd.c:451:1: Parameter `ctx->stack.depth`
      449.    * not contain branches that may leak sensitive information.
      450.    */
      451. > static BIGNUM *BN_mod_inverse_no_branch(BIGNUM *in,
      452.                                           const BIGNUM *a, const BIGNUM *n,
      453.                                           BN_CTX *ctx)

crypto/bn/bn_gcd.c:462:5: Call
      460.       bn_check_top(n);
      461.   
      462.       BN_CTX_start(ctx);
                 ^
      463.       A = BN_CTX_get(ctx);
      464.       B = BN_CTX_get(ctx);

crypto/bn/bn_ctx.c:181:1: Parameter `ctx->stack.depth`
        179.   }
        180.   
        181. > void BN_CTX_start(BN_CTX *ctx)
        182.   {
        183.       CTXDBG_ENTRY("BN_CTX_start", ctx);

crypto/bn/bn_gcd.c:497:18: Call
      495.               bn_init(&local_B);
      496.               BN_with_flags(&local_B, B, BN_FLG_CONSTTIME);
      497.               if (!BN_nnmod(B, &local_B, A, ctx))
                              ^
      498.                   goto err;
      499.               /* Ensure local_B goes out of scope before any further use of B */

crypto/bn/bn_mod.c:13:1: Parameter `ctx->stack.depth`
        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:137:1: Parameter `ctx->stack.depth`
          135.    * If 'dv' or 'rm' is NULL, the respective value is not returned.
          136.    */
          137. > int BN_div(BIGNUM *dv, BIGNUM *rm, const BIGNUM *num, const BIGNUM *divisor,
          138.              BN_CTX *ctx)
          139.   {

crypto/bn/bn_div.c:190:5: Call
          188.       }
          189.   
          190.       BN_CTX_start(ctx);
                     ^
          191.       res = (dv == NULL) ? BN_CTX_get(ctx) : dv;
          192.       tmp = BN_CTX_get(ctx);

crypto/bn/bn_ctx.c:181:1: Parameter `ctx->stack.depth`
            179.   }
            180.   
            181. > void BN_CTX_start(BN_CTX *ctx)
            182.   {
            183.       CTXDBG_ENTRY("BN_CTX_start", ctx);

crypto/bn/bn_div.c:410:5: Call
          408.       if (no_branch)
          409.           bn_correct_top(res);
          410.       BN_CTX_end(ctx);
                     ^
          411.       return 1;
          412.    err:

crypto/bn/bn_ctx.c:195:1: Parameter `ctx->stack.depth`
            193.   }
            194.   
            195. > void BN_CTX_end(BN_CTX *ctx)
            196.   {
            197.       CTXDBG_ENTRY("BN_CTX_end", ctx);

crypto/bn/bn_ctx.c:201:27: Call
            199.           ctx->err_stack--;
            200.       else {
            201.           unsigned int fp = BN_STACK_pop(&ctx->stack);
                                             ^
            202.           /* Does this stack frame have anything to release? */
            203.           if (fp < ctx->used)

crypto/bn/bn_ctx.c:271:1: <LHS trace>
269.   }
270.   
271. > static unsigned int BN_STACK_pop(BN_STACK *st)
272.   {
273.       return st->indexes[--(st->depth)];

crypto/bn/bn_ctx.c:271:1: Parameter `st->depth`
              269.   }
              270.   
              271. > static unsigned int BN_STACK_pop(BN_STACK *st)
              272.   {
              273.       return st->indexes[--(st->depth)];

crypto/bn/bn_ctx.c:273:12: Binary operation: ([0, +oo] - 1):unsigned32 by call to `BN_mod_inverse` 
              271.   static unsigned int BN_STACK_pop(BN_STACK *st)
              272.   {
              273.       return st->indexes[--(st->depth)];
                                ^
              274.   }
              275.   

static unsigned int BN_STACK_pop(BN_STACK *st)
{
    return st->indexes[--(st->depth)];
}
['static int rsa_builtin_keygen(RSA *rsa, int bits, int primes, BIGNUM *e_value,\n                              BN_GENCB *cb)\n{\n    BIGNUM *r0 = NULL, *r1 = NULL, *r2 = NULL, *tmp, *prime;\n    int ok = -1, n = 0, bitsr[RSA_MAX_PRIME_NUM], bitse = 0;\n    int i = 0, quo = 0, rmd = 0, adj = 0, retries = 0;\n    RSA_PRIME_INFO *pinfo = NULL;\n    STACK_OF(RSA_PRIME_INFO) *prime_infos = NULL;\n    BN_CTX *ctx = NULL;\n    BN_ULONG bitst = 0;\n    unsigned long error = 0;\n    if (bits < RSA_MIN_MODULUS_BITS) {\n        ok = 0;\n        RSAerr(RSA_F_RSA_BUILTIN_KEYGEN, RSA_R_KEY_SIZE_TOO_SMALL);\n        goto err;\n    }\n    if (primes < RSA_DEFAULT_PRIME_NUM || primes > rsa_multip_cap(bits)) {\n        ok = 0;\n        RSAerr(RSA_F_RSA_BUILTIN_KEYGEN, RSA_R_KEY_PRIME_NUM_INVALID);\n        goto err;\n    }\n    ctx = BN_CTX_new();\n    if (ctx == NULL)\n        goto err;\n    BN_CTX_start(ctx);\n    r0 = BN_CTX_get(ctx);\n    r1 = BN_CTX_get(ctx);\n    r2 = BN_CTX_get(ctx);\n    if (r2 == NULL)\n        goto err;\n    quo = bits / primes;\n    rmd = bits % primes;\n    for (i = 0; i < primes; i++)\n        bitsr[i] = (i < rmd) ? quo + 1 : quo;\n    if (!rsa->n && ((rsa->n = BN_new()) == NULL))\n        goto err;\n    if (!rsa->d && ((rsa->d = BN_secure_new()) == NULL))\n        goto err;\n    if (!rsa->e && ((rsa->e = BN_new()) == NULL))\n        goto err;\n    if (!rsa->p && ((rsa->p = BN_secure_new()) == NULL))\n        goto err;\n    if (!rsa->q && ((rsa->q = BN_secure_new()) == NULL))\n        goto err;\n    if (!rsa->dmp1 && ((rsa->dmp1 = BN_secure_new()) == NULL))\n        goto err;\n    if (!rsa->dmq1 && ((rsa->dmq1 = BN_secure_new()) == NULL))\n        goto err;\n    if (!rsa->iqmp && ((rsa->iqmp = BN_secure_new()) == NULL))\n        goto err;\n    if (primes > RSA_DEFAULT_PRIME_NUM) {\n        rsa->version = RSA_ASN1_VERSION_MULTI;\n        prime_infos = sk_RSA_PRIME_INFO_new_reserve(NULL, primes - 2);\n        if (prime_infos == NULL)\n            goto err;\n        if (rsa->prime_infos != NULL) {\n            sk_RSA_PRIME_INFO_pop_free(rsa->prime_infos, rsa_multip_info_free);\n        }\n        rsa->prime_infos = prime_infos;\n        for (i = 2; i < primes; i++) {\n            pinfo = rsa_multip_info_new();\n            if (pinfo == NULL)\n                goto err;\n            (void)sk_RSA_PRIME_INFO_push(prime_infos, pinfo);\n        }\n    }\n    if (BN_copy(rsa->e, e_value) == NULL)\n        goto err;\n    for (i = 0; i < primes; i++) {\n        adj = 0;\n        retries = 0;\n        if (i == 0) {\n            prime = rsa->p;\n        } else if (i == 1) {\n            prime = rsa->q;\n        } else {\n            pinfo = sk_RSA_PRIME_INFO_value(prime_infos, i - 2);\n            prime = pinfo->r;\n        }\n        for (;;) {\n redo:\n            if (!BN_generate_prime_ex(prime, bitsr[i] + adj, 0, NULL, NULL, cb))\n                goto err;\n            {\n                int j;\n                for (j = 0; j < i; j++) {\n                    BIGNUM *prev_prime;\n                    if (j == 0)\n                        prev_prime = rsa->p;\n                    else if (j == 1)\n                        prev_prime = rsa->q;\n                    else\n                        prev_prime = sk_RSA_PRIME_INFO_value(prime_infos,\n                                                             j - 2)->r;\n                    if (!BN_cmp(prime, prev_prime)) {\n                        goto redo;\n                    }\n                }\n            }\n            if (!BN_sub(r2, prime, BN_value_one()))\n                goto err;\n            ERR_set_mark();\n            BN_set_flags(r2, BN_FLG_CONSTTIME);\n            if (BN_mod_inverse(r1, r2, rsa->e, ctx) != NULL) {\n                break;\n            }\n            error = ERR_peek_last_error();\n            if (ERR_GET_LIB(error) == ERR_LIB_BN\n                && ERR_GET_REASON(error) == BN_R_NO_INVERSE) {\n                ERR_pop_to_mark();\n            } else {\n                goto err;\n            }\n            if (!BN_GENCB_call(cb, 2, n++))\n                goto err;\n        }\n        bitse += bitsr[i];\n        if (i == 1) {\n            if (!BN_mul(r1, rsa->p, rsa->q, ctx))\n                goto err;\n        } else if (i != 0) {\n            if (!BN_mul(r1, rsa->n, prime, ctx))\n                goto err;\n        } else {\n            if (!BN_GENCB_call(cb, 3, i))\n                goto err;\n            continue;\n        }\n        if (!BN_rshift(r2, r1, bitse - 4))\n            goto err;\n        bitst = BN_get_word(r2);\n        if (bitst < 0x9 || bitst > 0xF) {\n            bitse -= bitsr[i];\n            if (!BN_GENCB_call(cb, 2, n++))\n                goto err;\n            if (primes > 4) {\n                if (bitst < 0x9)\n                    adj++;\n                else\n                    adj--;\n            } else if (retries == 4) {\n                i = -1;\n                bitse = 0;\n                continue;\n            }\n            retries++;\n            goto redo;\n        }\n        if (i > 1 && BN_copy(pinfo->pp, rsa->n) == NULL)\n            goto err;\n        if (BN_copy(rsa->n, r1) == NULL)\n            goto err;\n        if (!BN_GENCB_call(cb, 3, i))\n            goto err;\n    }\n    if (BN_cmp(rsa->p, rsa->q) < 0) {\n        tmp = rsa->p;\n        rsa->p = rsa->q;\n        rsa->q = tmp;\n    }\n    if (!BN_sub(r1, rsa->p, BN_value_one()))\n        goto err;\n    if (!BN_sub(r2, rsa->q, BN_value_one()))\n        goto err;\n    if (!BN_mul(r0, r1, r2, ctx))\n        goto err;\n    for (i = 2; i < primes; i++) {\n        pinfo = sk_RSA_PRIME_INFO_value(prime_infos, i - 2);\n        if (!BN_sub(pinfo->d, pinfo->r, BN_value_one()))\n            goto err;\n        if (!BN_mul(r0, r0, pinfo->d, ctx))\n            goto err;\n    }\n    {\n        BIGNUM *pr0 = BN_new();\n        if (pr0 == NULL)\n            goto err;\n        BN_with_flags(pr0, r0, BN_FLG_CONSTTIME);\n        if (!BN_mod_inverse(rsa->d, rsa->e, pr0, ctx)) {\n            BN_free(pr0);\n            goto err;\n        }\n        BN_free(pr0);\n    }\n    {\n        BIGNUM *d = BN_new();\n        if (d == NULL)\n            goto err;\n        BN_with_flags(d, rsa->d, BN_FLG_CONSTTIME);\n        if (!BN_mod(rsa->dmp1, d, r1, ctx)\n            || !BN_mod(rsa->dmq1, d, r2, ctx)) {\n            BN_free(d);\n            goto err;\n        }\n        for (i = 2; i < primes; i++) {\n            pinfo = sk_RSA_PRIME_INFO_value(prime_infos, i - 2);\n            if (!BN_mod(pinfo->d, d, pinfo->d, ctx)) {\n                BN_free(d);\n                goto err;\n            }\n        }\n        BN_free(d);\n    }\n    {\n        BIGNUM *p = BN_new();\n        if (p == NULL)\n            goto err;\n        BN_with_flags(p, rsa->p, BN_FLG_CONSTTIME);\n        if (!BN_mod_inverse(rsa->iqmp, rsa->q, p, ctx)) {\n            BN_free(p);\n            goto err;\n        }\n        for (i = 2; i < primes; i++) {\n            pinfo = sk_RSA_PRIME_INFO_value(prime_infos, i - 2);\n            BN_with_flags(p, pinfo->r, BN_FLG_CONSTTIME);\n            if (!BN_mod_inverse(pinfo->t, pinfo->pp, p, ctx)) {\n                BN_free(p);\n                goto err;\n            }\n        }\n        BN_free(p);\n    }\n    ok = 1;\n err:\n    if (ok == -1) {\n        RSAerr(RSA_F_RSA_BUILTIN_KEYGEN, ERR_LIB_BN);\n        ok = 0;\n    }\n    if (ctx != NULL)\n        BN_CTX_end(ctx);\n    BN_CTX_free(ctx);\n    return ok;\n}', 'void BN_CTX_start(BN_CTX *ctx)\n{\n    CTXDBG_ENTRY("BN_CTX_start", ctx);\n    if (ctx->err_stack || ctx->too_many)\n        ctx->err_stack++;\n    else if (!BN_STACK_push(&ctx->stack, ctx->used)) {\n        BNerr(BN_F_BN_CTX_START, BN_R_TOO_MANY_TEMPORARY_VARIABLES);\n        ctx->err_stack++;\n    }\n    CTXDBG_EXIT(ctx);\n}', 'BIGNUM *BN_mod_inverse(BIGNUM *in,\n                       const BIGNUM *a, const BIGNUM *n, BN_CTX *ctx)\n{\n    BIGNUM *rv;\n    int noinv;\n    rv = int_bn_mod_inverse(in, a, n, ctx, &noinv);\n    if (noinv)\n        BNerr(BN_F_BN_MOD_INVERSE, BN_R_NO_INVERSE);\n    return rv;\n}', 'BIGNUM *int_bn_mod_inverse(BIGNUM *in,\n                           const BIGNUM *a, const BIGNUM *n, BN_CTX *ctx,\n                           int *pnoinv)\n{\n    BIGNUM *A, *B, *X, *Y, *M, *D, *T, *R = NULL;\n    BIGNUM *ret = NULL;\n    int sign;\n    if (pnoinv)\n        *pnoinv = 0;\n    if ((BN_get_flags(a, BN_FLG_CONSTTIME) != 0)\n        || (BN_get_flags(n, BN_FLG_CONSTTIME) != 0)) {\n        return BN_mod_inverse_no_branch(in, a, n, ctx);\n    }\n    bn_check_top(a);\n    bn_check_top(n);\n    BN_CTX_start(ctx);\n    A = BN_CTX_get(ctx);\n    B = BN_CTX_get(ctx);\n    X = BN_CTX_get(ctx);\n    D = BN_CTX_get(ctx);\n    M = BN_CTX_get(ctx);\n    Y = BN_CTX_get(ctx);\n    T = BN_CTX_get(ctx);\n    if (T == NULL)\n        goto err;\n    if (in == NULL)\n        R = BN_new();\n    else\n        R = in;\n    if (R == NULL)\n        goto err;\n    BN_one(X);\n    BN_zero(Y);\n    if (BN_copy(B, a) == NULL)\n        goto err;\n    if (BN_copy(A, n) == NULL)\n        goto err;\n    A->neg = 0;\n    if (B->neg || (BN_ucmp(B, A) >= 0)) {\n        if (!BN_nnmod(B, B, A, ctx))\n            goto err;\n    }\n    sign = -1;\n    if (BN_is_odd(n) && (BN_num_bits(n) <= 2048)) {\n        int shift;\n        while (!BN_is_zero(B)) {\n            shift = 0;\n            while (!BN_is_bit_set(B, shift)) {\n                shift++;\n                if (BN_is_odd(X)) {\n                    if (!BN_uadd(X, X, n))\n                        goto err;\n                }\n                if (!BN_rshift1(X, X))\n                    goto err;\n            }\n            if (shift > 0) {\n                if (!BN_rshift(B, B, shift))\n                    goto err;\n            }\n            shift = 0;\n            while (!BN_is_bit_set(A, shift)) {\n                shift++;\n                if (BN_is_odd(Y)) {\n                    if (!BN_uadd(Y, Y, n))\n                        goto err;\n                }\n                if (!BN_rshift1(Y, Y))\n                    goto err;\n            }\n            if (shift > 0) {\n                if (!BN_rshift(A, A, shift))\n                    goto err;\n            }\n            if (BN_ucmp(B, A) >= 0) {\n                if (!BN_uadd(X, X, Y))\n                    goto err;\n                if (!BN_usub(B, B, A))\n                    goto err;\n            } else {\n                if (!BN_uadd(Y, Y, X))\n                    goto err;\n                if (!BN_usub(A, A, B))\n                    goto err;\n            }\n        }\n    } else {\n        while (!BN_is_zero(B)) {\n            BIGNUM *tmp;\n            if (BN_num_bits(A) == BN_num_bits(B)) {\n                if (!BN_one(D))\n                    goto err;\n                if (!BN_sub(M, A, B))\n                    goto err;\n            } else if (BN_num_bits(A) == BN_num_bits(B) + 1) {\n                if (!BN_lshift1(T, B))\n                    goto err;\n                if (BN_ucmp(A, T) < 0) {\n                    if (!BN_one(D))\n                        goto err;\n                    if (!BN_sub(M, A, B))\n                        goto err;\n                } else {\n                    if (!BN_sub(M, A, T))\n                        goto err;\n                    if (!BN_add(D, T, B))\n                        goto err;\n                    if (BN_ucmp(A, D) < 0) {\n                        if (!BN_set_word(D, 2))\n                            goto err;\n                    } else {\n                        if (!BN_set_word(D, 3))\n                            goto err;\n                        if (!BN_sub(M, M, B))\n                            goto err;\n                    }\n                }\n            } else {\n                if (!BN_div(D, M, A, B, ctx))\n                    goto err;\n            }\n            tmp = A;\n            A = B;\n            B = M;\n            if (BN_is_one(D)) {\n                if (!BN_add(tmp, X, Y))\n                    goto err;\n            } else {\n                if (BN_is_word(D, 2)) {\n                    if (!BN_lshift1(tmp, X))\n                        goto err;\n                } else if (BN_is_word(D, 4)) {\n                    if (!BN_lshift(tmp, X, 2))\n                        goto err;\n                } else if (D->top == 1) {\n                    if (!BN_copy(tmp, X))\n                        goto err;\n                    if (!BN_mul_word(tmp, D->d[0]))\n                        goto err;\n                } else {\n                    if (!BN_mul(tmp, D, X, ctx))\n                        goto err;\n                }\n                if (!BN_add(tmp, tmp, Y))\n                    goto err;\n            }\n            M = Y;\n            Y = X;\n            X = tmp;\n            sign = -sign;\n        }\n    }\n    if (sign < 0) {\n        if (!BN_sub(Y, n, Y))\n            goto err;\n    }\n    if (BN_is_one(A)) {\n        if (!Y->neg && BN_ucmp(Y, n) < 0) {\n            if (!BN_copy(R, Y))\n                goto err;\n        } else {\n            if (!BN_nnmod(R, Y, n, ctx))\n                goto err;\n        }\n    } else {\n        if (pnoinv)\n            *pnoinv = 1;\n        goto err;\n    }\n    ret = R;\n err:\n    if ((ret == NULL) && (in == NULL))\n        BN_free(R);\n    BN_CTX_end(ctx);\n    bn_check_top(ret);\n    return ret;\n}', 'static BIGNUM *BN_mod_inverse_no_branch(BIGNUM *in,\n                                        const BIGNUM *a, const BIGNUM *n,\n                                        BN_CTX *ctx)\n{\n    BIGNUM *A, *B, *X, *Y, *M, *D, *T, *R = NULL;\n    BIGNUM *ret = NULL;\n    int sign;\n    bn_check_top(a);\n    bn_check_top(n);\n    BN_CTX_start(ctx);\n    A = BN_CTX_get(ctx);\n    B = BN_CTX_get(ctx);\n    X = BN_CTX_get(ctx);\n    D = BN_CTX_get(ctx);\n    M = BN_CTX_get(ctx);\n    Y = BN_CTX_get(ctx);\n    T = BN_CTX_get(ctx);\n    if (T == NULL)\n        goto err;\n    if (in == NULL)\n        R = BN_new();\n    else\n        R = in;\n    if (R == NULL)\n        goto err;\n    BN_one(X);\n    BN_zero(Y);\n    if (BN_copy(B, a) == NULL)\n        goto err;\n    if (BN_copy(A, n) == NULL)\n        goto err;\n    A->neg = 0;\n    if (B->neg || (BN_ucmp(B, A) >= 0)) {\n         {\n            BIGNUM local_B;\n            bn_init(&local_B);\n            BN_with_flags(&local_B, B, BN_FLG_CONSTTIME);\n            if (!BN_nnmod(B, &local_B, A, ctx))\n                goto err;\n        }\n    }\n    sign = -1;\n    while (!BN_is_zero(B)) {\n        BIGNUM *tmp;\n        {\n            BIGNUM local_A;\n            bn_init(&local_A);\n            BN_with_flags(&local_A, A, BN_FLG_CONSTTIME);\n            if (!BN_div(D, M, &local_A, B, ctx))\n                goto err;\n        }\n        tmp = A;\n        A = B;\n        B = M;\n        if (!BN_mul(tmp, D, X, ctx))\n            goto err;\n        if (!BN_add(tmp, tmp, Y))\n            goto err;\n        M = Y;\n        Y = X;\n        X = tmp;\n        sign = -sign;\n    }\n    if (sign < 0) {\n        if (!BN_sub(Y, n, Y))\n            goto err;\n    }\n    if (BN_is_one(A)) {\n        if (!Y->neg && BN_ucmp(Y, n) < 0) {\n            if (!BN_copy(R, Y))\n                goto err;\n        } else {\n            if (!BN_nnmod(R, Y, n, ctx))\n                goto err;\n        }\n    } else {\n        BNerr(BN_F_BN_MOD_INVERSE_NO_BRANCH, BN_R_NO_INVERSE);\n        goto err;\n    }\n    ret = R;\n err:\n    if ((ret == NULL) && (in == NULL))\n        BN_free(R);\n    BN_CTX_end(ctx);\n    bn_check_top(ret);\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}', 'void BN_CTX_end(BN_CTX *ctx)\n{\n    CTXDBG_ENTRY("BN_CTX_end", ctx);\n    if (ctx->err_stack)\n        ctx->err_stack--;\n    else {\n        unsigned int fp = BN_STACK_pop(&ctx->stack);\n        if (fp < ctx->used)\n            BN_POOL_release(&ctx->pool, ctx->used - fp);\n        ctx->used = fp;\n        ctx->too_many = 0;\n    }\n    CTXDBG_EXIT(ctx);\n}', 'static unsigned int BN_STACK_pop(BN_STACK *st)\n{\n    return st->indexes[--(st->depth)];\n}']