1）示例1
#include <openssl/bn.h>
#include <string.h>
#include <openssl/bio.h>
int main()
{
BIGNUM*bn;
BIO *b;
chara[20];
int ret;
bn=BN_new();
strcpy(a,"32");
ret=BN_hex2bn(&bn,a);
b=BIO_new(BIO_s_file());
ret=BIO_set_fp(b,stdout,BIO_NOCLOSE);
BIO_write(b,"aaa",3);
BN_print(b,bn);
BN_free(bn);
return 0;
}
2）示例2
加法运算
#include <openssl/bn.h>
#include <string.h>
#include <openssl/bio.h>
int main()
{
BIGNUM*a,*b,*add;
BIO *out;
charc[20],d[20];
int ret;
a=BN_new();
strcpy(c,"32");
ret=BN_hex2bn(&a,c);
b=BN_new();
strcpy(d,"100");
ret=BN_hex2bn(&b,d);
out=BIO_new(BIO_s_file());
ret=BIO_set_fp(out,stdout,BIO_NOCLOSE);
add=BN_new();
ret=BN_add(add,a,b);
if(ret!=1)
{
printf("err.\n");
return -1;
}
BIO_puts(out,"bn 0x32 + 0x100 = 0x");
BN_print(out,add);
BIO_puts(out,"\n");
BN_free(a);
BN_free(b);
BN_free(add);
BIO_free(out);
return 0;
}
3） 示例3
减法运算
#include <openssl/bn.h>
#include <string.h>
#include <openssl/bio.h>
int main()
{
BIGNUM*a,*b,*sub;
BIO *out;
charc[20],d[20];
int ret;
a=BN_new();
strcpy(c,"100");
ret=BN_hex2bn(&a,c);
b=BN_new();
strcpy(d,"32");
ret=BN_hex2bn(&b,d);
out=BIO_new(BIO_s_file());
ret=BIO_set_fp(out,stdout,BIO_NOCLOSE);
sub=BN_new();
ret=BN_sub(sub,a,b);
if(ret!=1)
{
printf("err.\n");
return -1;
}
BIO_puts(out,"bn 0x100 - 0x32 = 0x");
BN_print(out,sub);
BIO_puts(out,"\n");
BN_free(a);
BN_free(b);
BN_free(sub);
BIO_free(out);
return 0;
}
4）示例4
乘法运算
#include <openssl/bn.h>
#include <string.h>
#include <openssl/bio.h>
int main()
{
BIGNUM*a,*b,*mul;
BN_CTX*ctx;
BIO *out;
charc[20],d[20];
int ret;
ctx=BN_CTX_new();
a=BN_new();
strcpy(c,"32");
ret=BN_hex2bn(&a,c);
b=BN_new();
strcpy(d,"100");
ret=BN_hex2bn(&b,d);
out=BIO_new(BIO_s_file());
ret=BIO_set_fp(out,stdout,BIO_NOCLOSE);
mul=BN_new();
ret=BN_mul(mul,a,b,ctx);
if(ret!=1)
{
printf("err.\n");
return -1;
}
BIO_puts(out,"bn 0x32 * 0x100 = 0x");
BN_print(out,mul);
BIO_puts(out,"\n");
BN_free(a);
BN_free(b);
BN_free(mul);
BIO_free(out);
BN_CTX_free(ctx);
return 0;
}
5）示例5
除法运算
#include <openssl/bn.h>
#include <string.h>
#include <openssl/bio.h>
int main()
{
BIGNUM*a,*b,*div,*rem;
BN_CTX*ctx;
BIO *out;
charc[20],d[20];
int ret;
ctx=BN_CTX_new();
a=BN_new();
strcpy(c,"100");
ret=BN_hex2bn(&a,c);
b=BN_new();
strcpy(d,"17");
ret=BN_hex2bn(&b,d);
out=BIO_new(BIO_s_file());
ret=BIO_set_fp(out,stdout,BIO_NOCLOSE);
div=BN_new();
rem=BN_new();
ret=BN_div(div,rem,a,b,ctx);
if(ret!=1)
{
printf("err.\n");
return -1;
}
BIO_puts(out,"bn 0x100 / 0x17 =0x");
BN_print(out,div);
BIO_puts(out,"\n");
BIO_puts(out,"bn 0x100 % 0x17 =0x");
BN_print(out,rem);
BIO_puts(out,"\n");
BN_free(a);
BN_free(b);
BN_free(div);
BN_free(rem);
BIO_free(out);
BN_CTX_free(ctx);
return 0;
}
6）示例6
平方运算
#include <openssl/bn.h>
#include <string.h>
#include <openssl/bio.h>
int main()
{
BIGNUM*a,*sqr;
BN_CTX*ctx;
BIO *out;
charc[20];
int ret;
ctx=BN_CTX_new();
a=BN_new();
strcpy(c,"100");
ret=BN_hex2bn(&a,c);
sqr=BN_new();
out=BIO_new(BIO_s_file());
ret=BIO_set_fp(out,stdout,BIO_NOCLOSE);
ret=BN_sqr(sqr,a,ctx);
if(ret!=1)
{
printf("err.\n");
return -1;
}
BIO_puts(out,"bn 0x100 sqr =0x");
BN_print(out,sqr);
BIO_puts(out,"\n");
BN_free(a);
BN_free(sqr);
BIO_free(out);
BN_CTX_free(ctx);
return 0;
}
7）示例7
次方运算
#include <openssl/bn.h>
#include <string.h>
#include <openssl/bio.h>
int main()
{
BIGNUM*a,*exp,*b;
BN_CTX*ctx;
BIO *out;
charc[20],d[20];
int ret;
ctx=BN_CTX_new();
a=BN_new();
strcpy(c,"100");
ret=BN_hex2bn(&a,c);
b=BN_new();
strcpy(d,"3");
ret=BN_hex2bn(&b,d);
exp=BN_new();
out=BIO_new(BIO_s_file());
ret=BIO_set_fp(out,stdout,BIO_NOCLOSE);
ret=BN_exp(exp,a,b,ctx);
if(ret!=1)
{
printf("err.\n");
return -1;
}
BIO_puts(out,"bn 0x100 exp 0x3 =0x");
BN_print(out,exp);
BIO_puts(out,"\n");
BN_free(a);
BN_free(b);
BN_free(exp);
BIO_free(out);
BN_CTX_free(ctx);
return 0;
}