test/bntest.c:700: error: INTEGER_OVERFLOW_L2
  ([0, +oo] - 1):unsigned32 by call to `BN_sqr`.
Showing all 11 steps of the trace


test/bntest.c:684:1: Parameter `ctx->stack.depth`
682.   }
683.   
684. > int test_sqr(BIO *bp, BN_CTX *ctx)
685.   {
686.       BIGNUM *a, *c, *d, *e;

test/bntest.c:700:9: Call
698.           BN_bntest_rand(a, 40 + i * 10, 0, 0);
699.           a->neg = rand_neg();
700.           BN_sqr(c, a, ctx);
               ^
701.           if (bp != NULL) {
702.               if (!results) {

crypto/bn/bn_sqr.c:17:1: Parameter `ctx->stack.depth`
  15.    * I've just gone over this and it is now %20 faster on x86 - eay - 27 Jun 96
  16.    */
  17. > int BN_sqr(BIGNUM *r, const BIGNUM *a, BN_CTX *ctx)
  18.   {
  19.       int max, al;

crypto/bn/bn_sqr.c:32:5: Call
  30.       }
  31.   
  32.       BN_CTX_start(ctx);
            ^
  33.       rr = (a != r) ? r : BN_CTX_get(ctx);
  34.       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_sqr.c:100:5: Call
  98.       bn_check_top(rr);
  99.       bn_check_top(tmp);
  100.       BN_CTX_end(ctx);
             ^
  101.       return (ret);
  102.   }

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_sqr` 
      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)];
}
['int test_sqr(BIO *bp, BN_CTX *ctx)\n{\n    BIGNUM *a, *c, *d, *e;\n    int i, ret = 0;\n    a = BN_new();\n    c = BN_new();\n    d = BN_new();\n    e = BN_new();\n    if (a == NULL || c == NULL || d == NULL || e == NULL) {\n        goto err;\n    }\n    for (i = 0; i < num0; i++) {\n        BN_bntest_rand(a, 40 + i * 10, 0, 0);\n        a->neg = rand_neg();\n        BN_sqr(c, a, ctx);\n        if (bp != NULL) {\n            if (!results) {\n                BN_print(bp, a);\n                BIO_puts(bp, " * ");\n                BN_print(bp, a);\n                BIO_puts(bp, " - ");\n            }\n            BN_print(bp, c);\n            BIO_puts(bp, "\\n");\n        }\n        BN_div(d, e, c, a, ctx);\n        BN_sub(d, d, a);\n        if (!BN_is_zero(d) || !BN_is_zero(e)) {\n            fprintf(stderr, "Square test failed!\\n");\n            goto err;\n        }\n    }\n    BN_hex2bn(&a,\n              "80000000000000008000000000000001"\n              "FFFFFFFFFFFFFFFE0000000000000000");\n    BN_sqr(c, a, ctx);\n    if (bp != NULL) {\n        if (!results) {\n            BN_print(bp, a);\n            BIO_puts(bp, " * ");\n            BN_print(bp, a);\n            BIO_puts(bp, " - ");\n        }\n        BN_print(bp, c);\n        BIO_puts(bp, "\\n");\n    }\n    BN_mul(d, a, a, ctx);\n    if (BN_cmp(c, d)) {\n        fprintf(stderr, "Square test failed: BN_sqr and BN_mul produce "\n                "different results!\\n");\n        goto err;\n    }\n    BN_hex2bn(&a,\n              "80000000000000000000000080000001"\n              "FFFFFFFE000000000000000000000000");\n    BN_sqr(c, a, ctx);\n    if (bp != NULL) {\n        if (!results) {\n            BN_print(bp, a);\n            BIO_puts(bp, " * ");\n            BN_print(bp, a);\n            BIO_puts(bp, " - ");\n        }\n        BN_print(bp, c);\n        BIO_puts(bp, "\\n");\n    }\n    BN_mul(d, a, a, ctx);\n    if (BN_cmp(c, d)) {\n        fprintf(stderr, "Square test failed: BN_sqr and BN_mul produce "\n                "different results!\\n");\n        goto err;\n    }\n    ret = 1;\n err:\n    BN_free(a);\n    BN_free(c);\n    BN_free(d);\n    BN_free(e);\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 (r != rr && BN_copy(r, rr) == NULL)\n        goto err;\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_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}', '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}']