tor/src/common/crypto.c

/* Copyright 2001,2002 Roger Dingledine, Matej Pfajfar. */
/* See LICENSE for licensing information */
/* $Id$ */

#include "crypto.h"

#include <stdlib.h>
#include <assert.h>

int crypto_global_init() 
{
  ERR_load_crypto_strings();
  return 0;
}

int crypto_global_cleanup()
{
  ERR_free_strings();
  return 0;
}

crypto_pk_env_t *crypto_new_pk_env(int type)
{
  crypto_pk_env_t *env;
  
  env = (crypto_pk_env_t *)malloc(sizeof(crypto_pk_env_t));
  if (!env)
    return 0;
  
  env->type = type;
  env->key = NULL;
  env->aux = NULL;
  
  switch(type) {
    case CRYPTO_PK_RSA:
    env->key = (unsigned char *)RSA_new();
    if (!env->key) {
      free((void *)env);
      return NULL;
    }
    break;
    default:
    free((void *)env);
    return NULL;
    break;
  }

  return env;
}

void crypto_free_pk_env(crypto_pk_env_t *env)
{
  assert(env);
  
  switch(env->type) {
    case CRYPTO_PK_RSA:
    if (env->key)
      RSA_free((RSA *)env->key);
    break;
    default:
    break;
  }
  
  free((void *)env);
  return;
}

crypto_cipher_env_t *crypto_new_cipher_env(int type)
{
  crypto_cipher_env_t *env;
  
  env = (crypto_cipher_env_t *)malloc(sizeof(crypto_cipher_env_t));
  if (!env)
    return NULL;
  
  env->type = type;
  env->key = NULL;
  env->iv = NULL;
  env->aux = NULL;
  
  switch(type) {
    case CRYPTO_CIPHER_IDENTITY:
    env->aux = (unsigned char *)malloc(sizeof(EVP_CIPHER_CTX));
    if (!env->aux) {
      free((void *)env);
      return NULL;
    }
    EVP_CIPHER_CTX_init((EVP_CIPHER_CTX *)env->aux);
    break;
    case CRYPTO_CIPHER_DES:
    env->aux = (unsigned char *)malloc(sizeof(EVP_CIPHER_CTX));
    if (!env->aux) {
      free((void *)env);
      return NULL;
    }
    env->key = (unsigned char *)malloc(8);
    if (!env->key) {
      free((void *)env->aux);
      free((void *)env);
      return NULL;
    }
    env->iv = (unsigned char *)malloc(8);
    if (!env->iv) {
      free((void *)env->key);
      free((void *)env->aux);
      return NULL;
    }
    EVP_CIPHER_CTX_init((EVP_CIPHER_CTX *)env->aux);
    break;
    case CRYPTO_CIPHER_RC4:
    env->aux = (unsigned char *)malloc(sizeof(EVP_CIPHER_CTX));
    if (!env->aux) {
      free((void *)env);
      return NULL;
    }
    env->key = (unsigned char *)malloc(16);
    if (!env->key) {
      free((void *)env->aux);
      free((void *)env);
      return NULL;
    }
    env->iv = (unsigned char *)malloc(16);
    if (!env->iv) {
      free((void *)env->key);
      free((void *)env->aux);
      return NULL;
    }
    break;
    EVP_CIPHER_CTX_init((EVP_CIPHER_CTX *)env->aux);
    default:
    free((void *)env);
    return NULL;
    break;
  }
  
  return env;
}

void crypto_free_cipher_env(crypto_cipher_env_t *env)
{
  assert(env);
  
  switch(env->type) {
    case CRYPTO_CIPHER_IDENTITY:
    if (env->aux) {
      EVP_CIPHER_CTX_cleanup((EVP_CIPHER_CTX *)env->aux);
      free((void *)env->aux);
    }
    break;
    case CRYPTO_CIPHER_DES:
    if (env->aux) {
      EVP_CIPHER_CTX_cleanup((EVP_CIPHER_CTX *)env->aux);
      free((void *)env->aux);
    }
    if (env->key)
      free((void *)env->key);
    if (env->iv)
      free((void *)env->iv);
    break;
    case CRYPTO_CIPHER_RC4:
    if (env->aux) {
      EVP_CIPHER_CTX_cleanup((EVP_CIPHER_CTX *)env->aux);
      free((void *)env->aux);
    }
    if (env->key)
      free((void *)env->key);
    if (env->iv)
      free((void *)env->iv);
    break;
    default:
    break;
  }
  
  free((void *)env);
  return;
}

/* public key crypto */
int crypto_pk_generate_key(crypto_pk_env_t *env)
{
  assert(env);
  
  switch(env->type) {
    case CRYPTO_PK_RSA:
    if (env->key)
      RSA_free((RSA *)env->key);
    env->key = (unsigned char *)RSA_generate_key(1024,65535, NULL, NULL);
    if (!env->key)
      return -1;
    break;
    default:
    return -1;
  }
  
  return 0;
}

int crypto_pk_read_private_key(crypto_pk_env_t *env, FILE *src)
{
  assert(env && src);
  
  switch(env->type) {
    case CRYPTO_PK_RSA:
    if (env->key)
      RSA_free((RSA *)env->key);
    env->key = (unsigned char *)PEM_read_RSAPrivateKey(src, (RSA **)&env->key, NULL, NULL);
    if (!env->key)
      return -1;
    break;
    default :
    return -1;
  }
  
  return 0;
}
int crypto_pk_read_public_key(crypto_pk_env_t *env, FILE *src)
{
  assert(env && src);
  
  switch(env->type) {
    case CRYPTO_PK_RSA:
    if (env->key)
      RSA_free((RSA *)env->key);
    env->key = (unsigned char *)PEM_read_RSAPublicKey(src, (RSA **)&env->key, NULL, NULL);
    if (!env->key)
      return -1;
    break;
    default :
    return -1;
  }
  
  return 0;
}

int crypto_pk_write_private_key(crypto_pk_env_t *env, FILE *dest)
{
  assert(env && dest);
  
  switch(env->type) {
    case CRYPTO_PK_RSA:
    if (!env->key)
      return -1;
    if (PEM_write_RSAPrivateKey(dest, (RSA *)env->key, NULL, NULL, 0,0, NULL) == 0)
      return -1;
    break;
    default :
    return -1;
  }
  
  return 0;
}
int crypto_pk_write_public_key(crypto_pk_env_t *env, FILE *dest)
{
  assert(env && dest);
  
  switch(env->type) {
    case CRYPTO_PK_RSA:
    if (!env->key)
      return -1;
    if (PEM_write_RSAPublicKey(dest, (RSA *)env->key) == 0)
      return -1;
    break;
    default :
    return -1;
  }
  
  return 0;
}

int crypto_pk_check_key(crypto_pk_env_t *env)
{
  assert(env);
  
  switch(env->type) {
    case CRYPTO_PK_RSA:
    return RSA_check_key((RSA *)env->key);
    default:
    return -1;
  }
}

int crypto_pk_set_key(crypto_pk_env_t *env, unsigned char *key)
{
  assert(env && key);
  
  switch(env->type) {
    case CRYPTO_PK_RSA:
    if (env->key)
      RSA_free((RSA *)env->key);
    env->key = key;
    break;
    default :
    return -1;
  }
  
  return 0;
}

int crypto_pk_public_encrypt(crypto_pk_env_t *env, unsigned char *from, int fromlen, unsigned char *to, int padding)
{
  assert(env && from && to);
  
  switch(env->type) {
    case CRYPTO_PK_RSA:
    return RSA_public_encrypt(fromlen, from, to, (RSA *)env->key, padding);
    default:
    return -1;
  }
}

int crypto_pk_private_decrypt(crypto_pk_env_t *env, unsigned char *from, int fromlen, unsigned char *to, int padding)
{
  assert(env && from && to);
  
  switch(env->type) {
    case CRYPTO_PK_RSA:
    return RSA_private_decrypt(fromlen, from, to, (RSA *)env->key, padding);
    default:
    return -1;
  }
}

/* symmetric crypto */
int crypto_cipher_set_iv(crypto_cipher_env_t *env, unsigned char *iv)
{
  assert(env && iv);
  
  switch(env->type) {
    case CRYPTO_CIPHER_IDENTITY:
     break;
    case CRYPTO_CIPHER_DES:
    case CRYPTO_CIPHER_RC4:
     if (env->iv)
      free((void *)env->iv);
      env->iv = iv;
      break;
    default:
     return -1;
  }
  
  return 0;
}
int crypto_cipher_set_key(crypto_cipher_env_t *env, unsigned char *key)
{
  assert(env && key);
  
  switch(env->type) {
    case CRYPTO_CIPHER_IDENTITY:
    break;
    case CRYPTO_CIPHER_DES:
    case CRYPTO_CIPHER_RC4:
    if (env->key)
      free((void *)env->key);
    env->key = key;
    break;
    default:
    return -1;
  }
  
  return 0;
}

int crypto_cipher_encrypt_init_cipher(crypto_cipher_env_t *env)
{
  assert(env);

  switch(env->type) {
    case CRYPTO_CIPHER_IDENTITY:
      return !(EVP_EncryptInit((EVP_CIPHER_CTX *)env->aux, EVP_enc_null(), env->key, env->iv));
    case CRYPTO_CIPHER_DES:
      return !(EVP_EncryptInit((EVP_CIPHER_CTX *)env->aux, EVP_des_ofb(), env->key, env->iv));
    case CRYPTO_CIPHER_RC4:
      return !(EVP_EncryptInit((EVP_CIPHER_CTX *)env->aux, EVP_rc4(), env->key, env->iv));
    default:
      return -1;
  }
  
  return 0;
}

int crypto_cipher_decrypt_init_cipher(crypto_cipher_env_t *env)
{
  assert(env);
  
  switch(env->type) {
    case CRYPTO_CIPHER_IDENTITY:
    return !(EVP_DecryptInit((EVP_CIPHER_CTX *)env->aux, EVP_enc_null(), env->key, env->iv));
    case CRYPTO_CIPHER_DES:
    return !(EVP_DecryptInit((EVP_CIPHER_CTX *)env->aux, EVP_des_ofb(), env->key, env->iv));
    case CRYPTO_CIPHER_RC4:
    return !(EVP_DecryptInit((EVP_CIPHER_CTX *)env->aux, EVP_rc4(), env->key, env->iv));
    default:
    return -1;
  }
  
    return 0;
}

int crypto_cipher_encrypt(crypto_cipher_env_t *env, unsigned char *from, unsigned int fromlen, unsigned char *to)
{
  int tolen;
  
  assert(env && from && to);
  
  return !(EVP_EncryptUpdate((EVP_CIPHER_CTX *)env->aux, to, &tolen, from, fromlen));
}

int crypto_cipher_decrypt(crypto_cipher_env_t *env, unsigned char *from, unsigned int fromlen, unsigned char *to)
{
  int tolen;
  
  assert(env && from && to);
  
  return !(EVP_DecryptUpdate((EVP_CIPHER_CTX *)env->aux, to, &tolen, from, fromlen));
}

/* SHA-1 */
int crypto_SHA_digest(unsigned char *m, int len, unsigned char *digest)
{
  assert(m && digest);
  return (SHA1(m,len,digest) == NULL);
}

/* random numbers */
int crypto_rand(unsigned int n, unsigned char *to)
{
  assert(to);
  return (RAND_bytes(to, n) == -1);
}

int crypto_pseudo_rand(unsigned int n, unsigned char *to)
{
  assert(to);
  return (RAND_pseudo_bytes(to, n) == -1);
}

/* errors */
char *crypto_perror()
{
  return (char *)ERR_reason_error_string(ERR_get_error());
}