用指定的n,e,d生成RSA的数据结构

代码包括

1。生成RSA的数据结构

2。用指定的n,e,d生成RSA的数据结构

3。用私钥加密

4。用公钥解密

5。SHA256报文摘要

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <openssl/sha.h>
#include <openssl/rsa.h>
void testRSAGen(){
    RSA    *r;
    int    bits=512,ret;
    unsigned long e=RSA_3;
    BIGNUM    *bne;
    r=RSA_generate_key(bits,e,NULL,NULL);
    RSA_print_fp(stdout,r,11);
    printf("--------------------------------/n");
    RSA_free(r);
    bne=BN_new();
    ret=BN_set_word(bne,e);
    r=RSA_new();
    ret=RSA_generate_key_ex(r,bits,bne,NULL);
    if(ret!=1)
    {
    printf("RSA_generate_key_ex err!/n");
    return -1;
    }
    //RSA_print_fp(stdout,r,11);
    RSA_free(r);

}
void testRSA(){
    RSA *r;
    BIGNUM *bne,*bnn,*bnd;

    int bits = 1024, ret, len, flen, padding, i;

    unsigned char *key, *p;
    BIO *b;
    //要加密的明文
    unsigned  char *in = "abcef";
    unsigned  char *encData,*decData,*tmpData;//加密后的数据/解密后的数据/临时指针

    //使用的密匙数据
    unsigned long e = 75011;
    const char *MODULUS="9EC7D9A2DC5B095F8E5F90295121F41262FAEFBE9AF57B772A71F1F9D9635F8769CB78DA2BCFE9B27FC1F3AD4A3D178F8C61981225EF5DEACBDC5665F12E691AA13DDD321A59CFCF376F002036612FF3C5E057A3007FF675AFA3EDE34DC23A1A2637294870EBE823F76B5CE21E25F3FA5137F5DE12437DE0118245B927B28221";
    const char *PRIVATE="8B26E30ECA6E8F3668F6FA78B0C55FB75A4A3FAD0667B152933A4991D7A815D1498F5E1EF44ACEF6CDF252E56F367DED5BA024DF6B267B7E36BD35552DFA0A4CC1E9D0A4BC8E7C76F98D4971441D6693745A0A76E175571BD160E4B1536A6EFF5A08EDA45236E96E7A4748CF4D031CA8B2F4CCE9F2E1286F432DE6495A535E43";

    //构建RSA数据结构
    bne = BN_new();
    bnd = BN_new();
    bnn = BN_new();
    ret = BN_set_word(bne, e);
    BN_hex2bn(&bnd, PRIVATE);
    BN_hex2bn(&bnn, MODULUS);

    r = RSA_new();
    r->e=bne;
    r->d=bnd;
    r->n=bnn;
    RSA_print_fp(stdout, r, 5);

    //准备输出的加密数据结构
    flen =  RSA_size(r);// - 11;
    encData =  (unsigned char *)malloc(flen);
    bzero(encData, flen);//memset(encData, 0, flen);

    printf("Begin RSA_private_encrypt .../n");
    ret =  RSA_private_encrypt(flen, in, encData, r,  RSA_NO_PADDING);
    if(ret < 0){
        printf("Encrypt failed!/n");
        return;
    }
    printf("Size:%d/n", ret);
    printf("ClearText:%s/n", in);
    printf("CipherText(Hex):/n");
    tmpData=encData;
    for  (i=0; i<ret; i++){
        printf("0xx, ", *tmpData);
        tmpData++;
    }
    printf("end private encrypt /n");
    printf("------------------------/n");


    //准备输出的解密数据结构
    flen =  RSA_size(r);// - 11;
    decData =  (unsigned char *)malloc(flen);
    bzero(decData, flen);//memset(encData, 0, flen);

    printf("Begin RSA_public_decrypt .../n");
    ret =  RSA_public_decrypt(flen, encData, decData, r,  RSA_NO_PADDING);
    if(ret < 0){
            printf("RSA_public_decrypt failed!/n");
            return;
    }
    printf("Size:%d/n", ret);
    printf("ClearText:%s/n", decData);

    free(encData);
    free(decData);
    RSA_free(r);

}
void testSHA256(){
    unsigned char in[]="asdfwerqrewrasfaser";
    unsigned char out[32];

    size_t n;
    int i;

    n=strlen((const char*)in);

    SHA256(in,n,out);
    printf("/n/nSHA256 digest result:/n");

    printf("%d/n",sizeof(out));

    for(i=0;i<32;i++)
        printf("%d",out[i]);
    printf("/n");

}
int main(void) {
    puts("!!!Hello World!!!");
    testSHA256();
    testRSA();
    return EXIT_SUCCESS;
}