OpenSSL 编程 - RSA 加密解密

gcc -o rsa-decrypt rsa-decrypt.c -lcrypto */ #include <openssl/rsa.h> #define MODULUS "C8FBCF21" #define PUBLIC_EXPONENT RSA_F4 #define PRIVATE_EXPONENT "97B55D7D" int main() { int ret, flen;      BIGNUM *bnn, *bne;      unsigned char in[] = {0x98, 0x79, 0xb2, 0x76};      unsigned char *out;      bnn = BN_new();      bne = BN_new();      BN_hex2bn(&bnn, MODULUS);      BN_set_word(bne, PUBLIC_EXPONENT);      RSA *r = RSA_new();      r-&gt;n = bnn;      r-&gt;e = bne;      RSA_print_fp(stdout, r, 5);      flen = RSA_size(r); out = (unsigned char *)malloc(flen);      bzero(out, flen);      printf("Begin decrypt... ");      ret = RSA_public_decrypt(sizeof(in), in, out, r, RSA_NO_PADDING); if (ret < 0) {          printf("Decrypt failed! "); return 1;      }      printf("Size:%d ", ret);      printf("ClearText:%s ", out);      free(out);      RSA_free(r); return 0; } 解密： /* gcc -o rsa-decrypt rsa-decrypt.c -lcrypto */ #include &lt;openssl/rsa.h> #define MODULUS "C8FBCF21" #define PUBLIC_EXPONENT RSA_F4 #define PRIVATE_EXPONENT "97B55D7D" int main() { int ret, flen;      BIGNUM *bnn, *bne;      unsigned char in[] = {0x98, 0x79, 0xb2, 0x76};      unsigned char *out;      bnn = BN_new();      bne = BN_new();      BN_hex2bn(&bnn, MODULUS);      BN_set_word(bne, PUBLIC_EXPONENT);      RSA *r = RSA_new();      r-&gt;n = bnn;      r-&gt;e = bne;      RSA_print_fp(stdout, r, 5);      flen = RSA_size(r); out = (unsigned char *)malloc(flen);      bzero(out, flen);      printf("Begin decrypt... ");      ret = RSA_public_decrypt(sizeof(in), in, out, r, RSA_NO_PADDING); if (ret &lt; 0) {          printf("Decrypt failed! "); return 1;      }      printf("Size:%d ", ret);      printf("ClearText:%s ", out);      free(out);      RSA_free(r); return 0; }