我尝试使用RSA_private_encrypt的openssl RSA函数签署明文消息的哈希值。散列存储在文本文件hash.txt中，而符号存储在sign.txt中。在这里，似乎没有问题。但是，当我使用RSA_public_decrypt解密符号时，我得到这样的运行时错误 - 错误：0407006A：rsa例程：RSA_padding_check_PKCS1_type_1：块类型不是01.
以下是我的代码，如果有人可以请一看，告诉我它有什么问题？我需要比较解密的符号（存储在dec.txt中）和散列，并建立它们的相等性来验证身份验证。
#include <openssl/rsa.h>
#include <openssl/pem.h>
#include <openssl/err.h>
#include <openssl/sha.h>
#include <iostream>
#include <fstream>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <fcntl.h>
#include <unistd.h>
#define KEY_LENGTH 2048
#define PUB_EXP 3
#define PRINT_KEYS
#define WRITE_TO_FILE
#define PT "A.txt"
#define HASH "hash.txt"
#define SIGN "sign.txt"
#define DEC "dec.txt"
const char* pub="public_B.pem";
const char* pri="private_B.pem";
int fileread(const char *Filename, unsigned char **input_buffer, unsigned int *size)
{
int fd = open(Filename, O_RDONLY);
if (fd < 0)
{
std::cerr << "Error in open file." << Filename <<std::endl;
//fclose(f1);
return 1;
}
unsigned int size_temp = lseek(fd, 0, SEEK_END);
lseek(fd, 0, SEEK_SET);
*input_buffer = (unsigned char*)malloc(size_temp * sizeof(unsigned char));
if(*input_buffer == NULL)
{
cerr << "Malloc failed for size for input_buffer" << size_temp*sizeof(unsigned char) << endl;
close(fd);
return 1;
}
//fread(void *ptr, size_t size, size_t nmemb, FILE *stream);
if(size_temp != read(fd, *input_buffer, size_temp))
{
cerr << "Could not read input file" << errno << endl;
free(*input_buffer);
close(fd);
return 1;
}
*size = size_temp;
close(fd);
return 0;
}
int filewrite( char * Filename, unsigned char *input_buffer, size_t size)
{
int fd = open(Filename, O_WRONLY | O_CREAT, S_IRUSR | S_IWUSR);
if (fd < 0)
{
cerr << "Error in open file." << Filename << errno << endl;
//fclose(f1);
return 1;
}
//fread(void *ptr, size_t size, size_t nmemb, FILE *stream);
if(size != write(fd, input_buffer, size))
{
cerr << "Could not read input file" << errno << endl;
close(fd);
return 1;
}
close(fd);
return 0;
}
using namespace std;
int main(void) {
size_t pri_len; // Length of private key
size_t pub_len; // Length of public key
RSA *pri_key; // Private key
RSA *pub_key; // Public key
char *encrypt = NULL; // Encrypted message
char *decrypt = NULL; // Decrypted message
char *err; // Buffer for any error messages
// Generate key pair
printf("***Reading RSA***\n\n");
fflush(stdout);
FILE * fp = fopen(pub,"rb");
if(fp == NULL)
{
printf("Unable to open public file %s \n",pub);
return 0;
}
pub_key = PEM_read_RSAPublicKey(fp, NULL, NULL, NULL);
fclose(fp);
FILE * fp2 = fopen(pri,"rb");
if(fp2== NULL)
{
printf("Unable to open private file %s \n",pri);
return 0;
}
pri_key = PEM_read_RSAPrivateKey(fp2, NULL, NULL, NULL);
fclose(fp2);
unsigned int size;
unsigned char *input_buffer;
unsigned int hsize;
unsigned int ssize;
unsigned int dsize;
//Reading the input file
int iret = fileread(PT, &input_buffer, &size);
if (iret != 0)
{
std::cout << "file read fail : " << PT <<std::endl;
free(input_buffer);
return 1;
}
cout << "Plaintext message: "<< input_buffer << endl;
cout << "Size of plaintext message: " << size << endl;
// terminate
//Creating a Hash Value of the message
unsigned char md[SHA256_DIGEST_LENGTH];
//unsigned char *SHA256(const unsigned char *d, size_t n, unsigned char *md);
SHA256(input_buffer, size, (unsigned char*)&md);
printf("Hash value:%s\n", md);
#ifdef WRITE_TO_FILE
// Write the signed hash to a file
hsize = sizeof(md);
iret = filewrite(HASH, (unsigned char*)md, hsize);
if (iret != 0)
{
cout << "file write fail : " << HASH << endl;
//free(hash_buffer);
return 1;
}
#endif
cout << "Size of hash file, hash.txt = " << hsize << endl;
//initializing sign_buffer size
unsigned char *sign_buffer;
sign_buffer = (unsigned char*)malloc(hsize*sizeof(unsigned char));
if(NULL == sign_buffer)
{
cout << "Malloc failed for size for sign_buffer " << size*sizeof(unsigned char) << endl;
free(input_buffer);
return 1;
}
// Encrypt the hash value
encrypt = (char*)malloc(RSA_size(pri_key));
int encrypt_len;
err = (char*)malloc(130);
if((encrypt_len = RSA_private_encrypt(hsize, md, (unsigned char*)encrypt, pri_key, RSA_PKCS1_PADDING)) == -1) {
ERR_load_crypto_strings();
ERR_error_string(ERR_get_error(), err);
fprintf(stderr, "Error encrypting message: %s\n", err);
}
sign_buffer = (unsigned char*)encrypt;
#ifdef WRITE_TO_FILE
// Write the signature to a file
ssize = hsize;
iret = filewrite(SIGN, sign_buffer, ssize);
if (iret != 0)
{
cout << "file write fail : " << SIGN << endl;
free(sign_buffer);
return 1;
}
#endif
cout << "Signed hash : " << sign_buffer << endl;
cout << "Size of signed hash: "<< ssize << endl;
// Decrypt it
unsigned char *dec_buffer;
dec_buffer = (unsigned char*)malloc(ssize*sizeof(unsigned char));
if(NULL == dec_buffer)
{
std::cout << "Malloc failed for size for dec_buffer " << size*sizeof(unsigned char) <<std::endl;
free(input_buffer);
return 1;
}
decrypt = (char*)malloc(encrypt_len);
//int RSA_public_decrypt(int flen, unsigned char *from, unsigned char *to, RSA *rsa, int padding);
if(RSA_public_decrypt(ssize, sign_buffer, (unsigned char*)decrypt, pub_key, RSA_PKCS1_PADDING) == -1) {
ERR_load_crypto_strings();
ERR_error_string(ERR_get_error(), err);
fprintf(stderr, "Error decrypting message: %s\n", err);
}
dec_buffer = (unsigned char*)decrypt;
#ifdef WRITE_TO_FILE
// Write the decrypted message to a file
//initializing dec_buffer size
dsize = ssize;
iret = filewrite(DEC, dec_buffer, dsize);
if (iret != 0)
{
cout << "file write fail : " << DEC << endl;
free(dec_buffer);
return 1;
}
cout << "Decrypted message: " << dec_buffer << endl;
cout << "Size of decrypted sign = "<< dsize<< endl;
#endif
return 0;
}
答案 0 :(得分：0)
这条线看起来不正确：
if(RSA_public_decrypt(ssize, sign_buffer, (unsigned char*)decrypt, pub_key, RSA_PKCS1_PADDING) == -1) {
第一个参数应该是sign_buffer处数据的长度，这是encrypt_len中存储的值。您正在使用ssize，它似乎是加密前摘要的长度。