新的OpenSSL,任何人可以给我一个提示如何从C文件初始化AES CTR模式.我知道这是方法的签名,但我有参数的问题,没有很多文档没有一个明确的例子如何进行简单的加密.如果有人可以举例说明这种方法的话,我将不胜感激.提前致谢！

void AES_ctr128_encrypt(const unsigned char *in, unsigned char *out,

const unsigned long length, const AES_KEY *key,

unsigned char ivec[AES_BLOCK_SIZE],

unsigned char ecount_buf[AES_BLOCK_SIZE],

unsigned int *num);

嗨,我非常感谢你的快速回答,这是非常有用的,而且是我在网络上找到的最好的例子.我试图打开一个长度不确定的文件,对它进行加密并写入另一个生成密文的文件,然后打开加密文件并恢复明文.我需要使用相当数量的MB的文件,因为我想对CPU的性能进行基准测试.然而,我在解密时仍然有问题.解密一个相当大的txt文件(1504KB)不知何故,它不会解密它完成,我得到一半的明文,另一半仍然加密.我认为这可能与iv的大小或我打电话的方式有关.这是我到目前为止

#include

#include

#include

struct ctr_state {

unsigned char ivec[16];

unsigned int num;

unsigned char ecount[16];

};

FILE *fp;

FILE *rp;

FILE *op;

size_t count;

char * buffer;

AES_KEY key;

int bytes_read, bytes_written;

unsigned char indata[AES_BLOCK_SIZE];

unsigned char outdata[AES_BLOCK_SIZE];

unsigned char ckey[] = "thiskeyisverybad"; // It is 128bits though..

unsigned char iv[8] = {0};//This should be generated by RAND_Bytes I will take into consideration your previous post

struct ctr_state state;

int init_ctr(struct ctr_state *state, const unsigned char iv[8]){

state->num = 0;

memset(state->ecount, 0, 16);

memset(state->ivec + 8, 0, 8);

memcpy(state->ivec, iv, 8);

}

void encrypt(){

//Opening files where text plain text is read and ciphertext stored

fp=fopen("input.txt","a+b");

op=fopen("output.txt","w");

if (fp==NULL) {fputs ("File error",stderr); exit (1);}

if (op==NULL) {fputs ("File error",stderr); exit (1);}

//Initializing the encryption KEY

AES_set_encrypt_key(ckey, 128, &key);

//Encrypting Blocks of 16 bytes and writing the output.txt with ciphertext

while (1) {

init_ctr(&state, iv); //Counter call

bytes_read = fread(indata, 1, AES_BLOCK_SIZE, fp);

AES_ctr128_encrypt(indata, outdata, bytes_read, &key, state.ivec, state.ecount, &state.num);

bytes_written = fwrite(outdata, 1, bytes_read, op);

if (bytes_read < AES_BLOCK_SIZE)

break;

}

fclose (fp);

fclose (op);

free (buffer);

}

void decrypt(){

//Opening files where text cipher text is read and the plaintext recovered

rp=fopen("recovered.txt","w");

op=fopen("output.txt","a+b");

if (rp==NULL) {fputs ("File error",stderr); exit (1);}

if (op==NULL) {fputs ("File error",stderr); exit (1);}

//Initializing the encryption KEY

AES_set_encrypt_key(ckey, 128, &key);

//Encrypting Blocks of 16 bytes and writing the output.txt with ciphertext

while (1) {

init_ctr(&state, iv);//Counter call

bytes_read = fread(indata, 1, AES_BLOCK_SIZE, op);

AES_ctr128_encrypt(indata, outdata, bytes_read, &key, state.ivec, state.ecount, &state.num);

bytes_written = fwrite(outdata, 1, bytes_read, rp);

if (bytes_read < AES_BLOCK_SIZE)

break;

}

fclose (rp);

fclose (op);

free (buffer);

}

int main(int argc, char *argv[]){

encrypt();

//decrypt();

system("PAUSE");

return 0;

}

每个加密和解密功能在不同的运行中被调用,所以所有的东西总是以相同的值初始化.再次感谢您提前提供的提示和提示.问候！！！