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以下是使用openssl EVP進行加密和解密的示例代碼。當我執行加密和解密時，它似乎工作正常。當我寫的encryted字符串中的文件，並從decript文件我收到錯誤Openssl EVP從文件加密和解密
encrypt.c
#include <openssl/conf.h>
#include <openssl/evp.h>
#include <openssl/err.h>
#include <openssl/bio.h>
#include <string.h>
#include <iostream>
#include <fstream>
#include <stdint.h>
#include <assert.h>
void handleErrors(void)
{
ERR_print_errors_fp(stderr);
abort();
}
int encrypt(unsigned char *plaintext, int plaintext_len, unsigned char *key,
unsigned char *iv, unsigned char *ciphertext)
{
EVP_CIPHER_CTX *ctx;
int len;
int ciphertext_len;
/* Create and initialise the context */
if(!(ctx = EVP_CIPHER_CTX_new())) handleErrors();
if(1 != EVP_EncryptInit_ex(ctx, EVP_aes_256_ecb(), NULL, key, iv))
handleErrors();
if(1 != EVP_EncryptUpdate(ctx, ciphertext, &len, plaintext, plaintext_len))
handleErrors();
ciphertext_len = len;
if(1 != EVP_EncryptFinal_ex(ctx, ciphertext + len, &len)) handleErrors();
ciphertext_len += len;
/* Clean up */
EVP_CIPHER_CTX_free(ctx);
return ciphertext_len;
}
int main (int argc, char *argv[])
{
if (argc != 2)
{
printf("Usage: <process> <file>\n");
exit(0);
}
/* A 256 bit key */
unsigned char *key = (unsigned char *) "key";
/* A 128 bit IV Should be hardcoded in both encrypt and decrypt. */
unsigned char *iv = (unsigned char *)"iv";
/* Message to be encrypted */
unsigned char *plaintext =
(unsigned char *)"Password";
unsigned char ciphertext[128],base64[128];
/* Buffer for the decrypted text */
unsigned char decryptedtext[128];
int decryptedtext_len, ciphertext_len;
/* Initialise the library */
ERR_load_crypto_strings();
OpenSSL_add_all_algorithms();
OPENSSL_config(NULL);
/* Encrypt the plaintext */
ciphertext_len = encrypt (plaintext, strlen ((char *)plaintext), key, iv,
ciphertext);
/* Do something useful with the ciphertext here */
printf("Ciphertext is:\n");
BIO_dump_fp (stdout, (const char *)ciphertext, ciphertext_len);
printf("%d %s\n", ciphertext_len, ciphertext);
int encode_str_size = EVP_EncodeBlock(base64, ciphertext, ciphertext_len);
printf("%d %s\n", encode_str_size, base64);
std::ofstream outFile (argv[1]);
outFile << base64;
outFile.close();
/* Clean up */
EVP_cleanup();
ERR_free_strings();
return 0;
}
decrypt.c
#include <openssl/conf.h>
#include <openssl/evp.h>
#include <openssl/err.h>
#include <string.h>
#include <iostream>
#include <fstream>
using namespace std;
void handleErrors(void)
{
ERR_print_errors_fp(stderr);
abort();
}
int decrypt(unsigned char *ciphertext, int ciphertext_len, unsigned char *key,
unsigned char *iv, unsigned char *plaintext)
{
EVP_CIPHER_CTX *ctx;
int len;
int plaintext_len;
/* Create and initialise the context */
if(!(ctx = EVP_CIPHER_CTX_new())) handleErrors();
if(1 != EVP_DecryptInit_ex(ctx, EVP_aes_256_ecb(), NULL, key, iv))
handleErrors();
if(1 != EVP_DecryptUpdate(ctx, plaintext, &len, ciphertext, ciphertext_len))
handleErrors();
plaintext_len = len;
if(1 != EVP_DecryptFinal_ex(ctx, plaintext + len, &len)) handleErrors();
plaintext_len += len;
/* Clean up */
EVP_CIPHER_CTX_free(ctx);
return plaintext_len;
}
int main (int argc, char *argv[])
{
if (argc != 2)
{
printf("Usage: <process> <file>\n");
exit(0);
}
/* A 256 bit key */
unsigned char *key = (unsigned char *)"key";
/* A 128 bit IV */
unsigned char *iv = (unsigned char *)"iv";
unsigned char ciphertext[128] = "", base64_in[128] = "", base64_out[128] = "";
/* Buffer for the decrypted text */
unsigned char decryptedtext[128]="";
int decryptedtext_len, ciphertext_len;
/* Initialise the library */
ERR_load_crypto_strings();
OpenSSL_add_all_algorithms();
OPENSSL_config(NULL);
/* Encrypt the plaintext */
char fileBuffer[128] = "";
ifstream infile (argv[1], ios::binary);
infile.getline(fileBuffer, sizeof(fileBuffer));
infile.close();
strcpy((char *)base64_in, fileBuffer);
ciphertext_len = (strlen(reinterpret_cast<const char *>(base64_in)));
printf("%d %s\n",ciphertext_len, base64_in);
int length = EVP_DecodeBlock(base64_out, base64_in, ciphertext_len);
while(base64_in[--ciphertext_len] == '=') length--;
printf("%d %s\n", length,base64_out);
BIO_dump_fp (stdout, (const char *)base64_out, length);
decryptedtext_len = decrypt(base64_out, length, key, iv,
decryptedtext);
/* Add a NULL terminator. We are expecting printable text */
decryptedtext[decryptedtext_len] = '\0';
/* Show the decrypted text */
printf("Decrypted text is:\n");
printf("%d %s\n", decryptedtext_len ,decryptedtext);
/* Clean up */
EVP_cleanup();
ERR_free_strings();
return 0;
}
輸出
./encrypt file
Ciphertext is:
0000 - 52 6f a3 c6 6b ea 4a aa-a5 e8 9d 26 47 dc e9 b7 Ro..k.J....&G...
16 Ro��k�J����&G�鷈H�t�
24 Um+jxmvqSqql6J0mR9zptw==
./decrypt file
24 Um+jxmvqSqql6J0mR9zptw==
16 Ro��k�J����&G���
0000 - 52 6f a3 c6 6b ea 4a aa-a5 e8 9d 26 47 dc e9 b7 Ro..k.J....&G...
140405999580856:error:06065064:digital envelope routines:EVP_DecryptFinal_ex:bad decrypt:evp_enc.c:529:
Aborted (core dumped)
核心
Core was generated by `./decrypt file'.
Program terminated with signal SIGABRT, Aborted.
#0 0x00007efe46356428 in __GI_raise ([email protected]=6) at ../sysdeps/unix/sysv/linux/raise.c:54
54 ../sysdeps/unix/sysv/linux/raise.c: No such file or directory.
(gdb) bt
#0 0x00007efe46356428 in __GI_raise ([email protected]=6) at ../sysdeps/unix/sysv/linux/raise.c:54
#1 0x00007efe4635802a in __GI_abort() at abort.c:89
#2 0x000000000040110e in handleErrors()()
#3 0x00000000004011eb in decrypt(unsigned char*, int, unsigned char*, unsigned char*, unsigned char*)()
#4 0x0000000000401485 in main()
當我寫入文件並從文件中讀取內容時，我無法解密。
很明顯**不是** C，而是C++！讓你的文本和文件擴展名正確！並且不要垃圾郵件標籤！ – Olaf
@Olaf用於加密的所有openssl/evp.h都在c中。 –
使用C庫不符合C標籤！ – Olaf