Use AES256 and SHA256 by default for the legacy protocol.
[tinc] / src / openssl / cipher.c
index 7f73cb1..17ad408 100644 (file)
@@ -1,6 +1,6 @@
 /*
     cipher.c -- Symmetric block cipher handling
-    Copyright (C) 2007-2013 Guus Sliepen <guus@tinc-vpn.org>
+    Copyright (C) 2007-2016 Guus Sliepen <guus@tinc-vpn.org>
 
     This program is free software; you can redistribute it and/or modify
     it under the terms of the GNU General Public License as published by
 #include "../xalloc.h"
 
 struct cipher {
-       EVP_CIPHER_CTX ctx;
+       EVP_CIPHER_CTX *ctx;
        const EVP_CIPHER *cipher;
-       struct cipher_counter *counter;
 };
 
-typedef struct cipher_counter {
-       unsigned char counter[CIPHER_MAX_IV_SIZE];
-       unsigned char block[CIPHER_MAX_IV_SIZE];
-       int n;
-} cipher_counter_t;
-
 static cipher_t *cipher_open(const EVP_CIPHER *evp_cipher) {
        cipher_t *cipher = xzalloc(sizeof *cipher);
        cipher->cipher = evp_cipher;
-       EVP_CIPHER_CTX_init(&cipher->ctx);
+       cipher->ctx = EVP_CIPHER_CTX_new();
+       if(!cipher->ctx)
+               abort();
 
        return cipher;
 }
@@ -67,30 +62,35 @@ cipher_t *cipher_open_by_nid(int nid) {
        return cipher_open(evp_cipher);
 }
 
-cipher_t *cipher_open_blowfish_ofb(void) {
-       return cipher_open(EVP_bf_ofb());
-}
-
 void cipher_close(cipher_t *cipher) {
        if(!cipher)
                return;
 
-       EVP_CIPHER_CTX_cleanup(&cipher->ctx);
-       free(cipher->counter);
+       EVP_CIPHER_CTX_free(cipher->ctx);
        free(cipher);
 }
 
 size_t cipher_keylength(const cipher_t *cipher) {
-       return cipher->cipher->key_len + cipher->cipher->block_size;
+       if(!cipher || !cipher->cipher)
+               return 0;
+
+       return EVP_CIPHER_key_length(cipher->cipher) + EVP_CIPHER_iv_length(cipher->cipher);
+}
+
+size_t cipher_blocksize(const cipher_t *cipher) {
+       if(!cipher || !cipher->cipher)
+               return 1;
+
+       return EVP_CIPHER_block_size(cipher->cipher);
 }
 
 bool cipher_set_key(cipher_t *cipher, void *key, bool encrypt) {
        bool result;
 
        if(encrypt)
-               result = EVP_EncryptInit_ex(&cipher->ctx, cipher->cipher, NULL, (unsigned char *)key, (unsigned char *)key + cipher->cipher->key_len);
+               result = EVP_EncryptInit_ex(cipher->ctx, cipher->cipher, NULL, (unsigned char *)key, (unsigned char *)key + EVP_CIPHER_key_length(cipher->cipher));
        else
-               result = EVP_DecryptInit_ex(&cipher->ctx, cipher->cipher, NULL, (unsigned char *)key, (unsigned char *)key + cipher->cipher->key_len);
+               result = EVP_DecryptInit_ex(cipher->ctx, cipher->cipher, NULL, (unsigned char *)key, (unsigned char *)key + EVP_CIPHER_key_length(cipher->cipher));
 
        if(result)
                return true;
@@ -103,9 +103,9 @@ bool cipher_set_key_from_rsa(cipher_t *cipher, void *key, size_t len, bool encry
        bool result;
 
        if(encrypt)
-               result = EVP_EncryptInit_ex(&cipher->ctx, cipher->cipher, NULL, (unsigned char *)key + len - cipher->cipher->key_len, (unsigned char *)key + len - cipher->cipher->iv_len - cipher->cipher->key_len);
+               result = EVP_EncryptInit_ex(cipher->ctx, cipher->cipher, NULL, (unsigned char *)key + len - EVP_CIPHER_key_length(cipher->cipher), (unsigned char *)key + len - EVP_CIPHER_iv_length(cipher->cipher) - EVP_CIPHER_key_length(cipher->cipher));
        else
-               result = EVP_DecryptInit_ex(&cipher->ctx, cipher->cipher, NULL, (unsigned char *)key + len - cipher->cipher->key_len, (unsigned char *)key + len - cipher->cipher->iv_len - cipher->cipher->key_len);
+               result = EVP_DecryptInit_ex(cipher->ctx, cipher->cipher, NULL, (unsigned char *)key + len - EVP_CIPHER_key_length(cipher->cipher), (unsigned char *)key + len - EVP_CIPHER_iv_length(cipher->cipher) - EVP_CIPHER_key_length(cipher->cipher));
 
        if(result)
                return true;
@@ -114,82 +114,18 @@ bool cipher_set_key_from_rsa(cipher_t *cipher, void *key, size_t len, bool encry
        return false;
 }
 
-bool cipher_set_counter(cipher_t *cipher, const void *counter, size_t len) {
-       if(len > cipher->cipher->block_size - 4) {
-               logger(DEBUG_ALWAYS, LOG_ERR, "Counter too long");
-               abort();
-       }
-
-       memcpy(cipher->counter->counter + cipher->cipher->block_size - len, counter, len);
-       memset(cipher->counter->counter, 0, 4);
-       cipher->counter->n = 0;
-
-       return true;
-}
-
-bool cipher_set_counter_key(cipher_t *cipher, void *key) {
-       int result = EVP_EncryptInit_ex(&cipher->ctx, cipher->cipher, NULL, (unsigned char *)key, NULL);
-       if(!result) {
-               logger(DEBUG_ALWAYS, LOG_ERR, "Error while setting key: %s", ERR_error_string(ERR_get_error(), NULL));
-               return false;
-       }
-
-       if(!cipher->counter)
-               cipher->counter = xzalloc(sizeof *cipher->counter);
-       else
-               cipher->counter->n = 0;
-
-       memcpy(cipher->counter->counter, (unsigned char *)key + cipher->cipher->key_len, cipher->cipher->block_size);
-
-       return true;
-}
-
-bool cipher_counter_xor(cipher_t *cipher, const void *indata, size_t inlen, void *outdata) {
-       if(!cipher->counter) {
-               logger(DEBUG_ALWAYS, LOG_ERR, "Counter not initialized");
-               return false;
-       }
-
-       const unsigned char *in = indata;
-       unsigned char *out = outdata;
-
-       while(inlen--) {
-               // Encrypt the new counter value if we need it
-               if(!cipher->counter->n) {
-                       int len;
-                       if(!EVP_EncryptUpdate(&cipher->ctx, cipher->counter->block, &len, cipher->counter->counter, cipher->cipher->block_size)) {
-                               logger(DEBUG_ALWAYS, LOG_ERR, "Error while encrypting: %s", ERR_error_string(ERR_get_error(), NULL));
-                               return false;
-                       }
-
-                       // Increase the counter value
-                       for(int i = 0; i < cipher->cipher->block_size; i++)
-                               if(++cipher->counter->counter[i])
-                                       break;
-               }
-
-               *out++ = *in++ ^ cipher->counter->counter[cipher->counter->n++];
-
-               if(cipher->counter->n >= cipher->cipher->block_size)
-                       cipher->counter->n = 0;
-       }
-
-       return true;
-}
-
-
 bool cipher_encrypt(cipher_t *cipher, const void *indata, size_t inlen, void *outdata, size_t *outlen, bool oneshot) {
        if(oneshot) {
                int len, pad;
-               if(EVP_EncryptInit_ex(&cipher->ctx, NULL, NULL, NULL, NULL)
-                               && EVP_EncryptUpdate(&cipher->ctx, (unsigned char *)outdata, &len, indata, inlen)
-                               && EVP_EncryptFinal(&cipher->ctx, (unsigned char *)outdata + len, &pad)) {
+               if(EVP_EncryptInit_ex(cipher->ctx, NULL, NULL, NULL, NULL)
+                               && EVP_EncryptUpdate(cipher->ctx, (unsigned char *)outdata, &len, indata, inlen)
+                               && EVP_EncryptFinal(cipher->ctx, (unsigned char *)outdata + len, &pad)) {
                        if(outlen) *outlen = len + pad;
                        return true;
                }
        } else {
                int len;
-               if(EVP_EncryptUpdate(&cipher->ctx, outdata, &len, indata, inlen)) {
+               if(EVP_EncryptUpdate(cipher->ctx, outdata, &len, indata, inlen)) {
                        if(outlen) *outlen = len;
                        return true;
                }
@@ -202,15 +138,15 @@ bool cipher_encrypt(cipher_t *cipher, const void *indata, size_t inlen, void *ou
 bool cipher_decrypt(cipher_t *cipher, const void *indata, size_t inlen, void *outdata, size_t *outlen, bool oneshot) {
        if(oneshot) {
                int len, pad;
-               if(EVP_DecryptInit_ex(&cipher->ctx, NULL, NULL, NULL, NULL)
-                               && EVP_DecryptUpdate(&cipher->ctx, (unsigned char *)outdata, &len, indata, inlen)
-                               && EVP_DecryptFinal(&cipher->ctx, (unsigned char *)outdata + len, &pad)) {
+               if(EVP_DecryptInit_ex(cipher->ctx, NULL, NULL, NULL, NULL)
+                               && EVP_DecryptUpdate(cipher->ctx, (unsigned char *)outdata, &len, indata, inlen)
+                               && EVP_DecryptFinal(cipher->ctx, (unsigned char *)outdata + len, &pad)) {
                        if(outlen) *outlen = len + pad;
                        return true;
                }
        } else {
                int len;
-               if(EVP_EncryptUpdate(&cipher->ctx, outdata, &len, indata, inlen)) {
+               if(EVP_EncryptUpdate(cipher->ctx, outdata, &len, indata, inlen)) {
                        if(outlen) *outlen = len;
                        return true;
                }
@@ -221,9 +157,12 @@ bool cipher_decrypt(cipher_t *cipher, const void *indata, size_t inlen, void *ou
 }
 
 int cipher_get_nid(const cipher_t *cipher) {
-       return cipher->cipher ? cipher->cipher->nid : 0;
+       if(!cipher || !cipher->cipher)
+               return 0;
+
+       return EVP_CIPHER_nid(cipher->cipher);
 }
 
 bool cipher_active(const cipher_t *cipher) {
-       return cipher && cipher->cipher && cipher->cipher->nid != 0;
+       return cipher && cipher->cipher && EVP_CIPHER_nid(cipher->cipher) != 0;
 }