X-Git-Url: https://tinc-vpn.org/git/browse?a=blobdiff_plain;f=src%2Fopenssl%2Fcipher.c;h=b2edcc75d625908dd94fb1f56fc0bd4de9c91daf;hb=d917c8cb6b69475d568ccbe82389b9f2b3eb5e80;hp=e5fe07d93401588265a3419db04b01053936316f;hpb=d6c50eb73ad49bd2eac67214995dff76b7a20661;p=tinc

diff --git a/src/openssl/cipher.c b/src/openssl/cipher.c
index e5fe07d9..b2edcc75 100644
--- a/src/openssl/cipher.c
+++ b/src/openssl/cipher.c
@@ -26,12 +26,13 @@
 #include "logger.h"
 #include "xalloc.h"
 
-static bool cipher_open(cipher_t *cipher) {
-	cipher->keylen = cipher->cipher->key_len;
-	cipher->blklen = cipher->cipher->iv_len;
-
-	cipher->key = xmalloc(cipher->keylen + cipher->blklen);
+typedef struct cipher_counter {
+	unsigned char counter[EVP_MAX_IV_LENGTH];
+	unsigned char block[EVP_MAX_IV_LENGTH];
+	int n;
+} cipher_counter_t;
 
+static bool cipher_open(cipher_t *cipher) {
 	EVP_CIPHER_CTX_init(&cipher->ctx);
 
 	return true;
@@ -43,7 +44,7 @@ bool cipher_open_by_name(cipher_t *cipher, const char *name) {
 	if(cipher->cipher)
 		return cipher_open(cipher);
 
-	logger(LOG_DEBUG, "Unknown cipher name '%s'!", name);
+	logger(DEBUG_ALWAYS, LOG_ERR, "Unknown cipher name '%s'!", name);
 	return false;
 }
 
@@ -53,7 +54,7 @@ bool cipher_open_by_nid(cipher_t *cipher, int nid) {
 	if(cipher->cipher)
 		return cipher_open(cipher);
 
-	logger(LOG_DEBUG, "Unknown cipher nid %d!", nid);
+	logger(DEBUG_ALWAYS, LOG_ERR, "Unknown cipher nid %d!", nid);
 	return false;
 }
 
@@ -64,110 +65,147 @@ bool cipher_open_blowfish_ofb(cipher_t *cipher) {
 
 void cipher_close(cipher_t *cipher) {
 	EVP_CIPHER_CTX_cleanup(&cipher->ctx);
-
-	if(cipher->key) {
-		free(cipher->key);
-		cipher->key = NULL;
-	}
+	free(cipher->counter);
+	cipher->counter = NULL;
 }
 
 size_t cipher_keylength(const cipher_t *cipher) {
-	return cipher->keylen + cipher->blklen;
-}
-
-void cipher_get_key(const cipher_t *cipher, void *key) {
-	memcpy(key, cipher->key, cipher->keylen + cipher->blklen);
+	return cipher->cipher->key_len + cipher->cipher->block_size;
 }
 
 bool cipher_set_key(cipher_t *cipher, void *key, bool encrypt) {
-	memcpy(cipher->key, key, cipher->keylen + cipher->blklen);
 	bool result;
 
 	if(encrypt)
-		result = EVP_EncryptInit_ex(&cipher->ctx, cipher->cipher, NULL, (unsigned char *)cipher->key, (unsigned char *)cipher->key + cipher->keylen);
+		result = EVP_EncryptInit_ex(&cipher->ctx, cipher->cipher, NULL, (unsigned char *)key, (unsigned char *)key + cipher->cipher->key_len);
 	else
-		result = EVP_DecryptInit_ex(&cipher->ctx, cipher->cipher, NULL, (unsigned char *)cipher->key, (unsigned char *)cipher->key + cipher->keylen);
+		result = EVP_DecryptInit_ex(&cipher->ctx, cipher->cipher, NULL, (unsigned char *)key, (unsigned char *)key + cipher->cipher->key_len);
 
 	if(result)
 		return true;
 
-	logger(LOG_ERR, "Error while setting key: %s", ERR_error_string(ERR_get_error(), NULL));
+	logger(DEBUG_ALWAYS, LOG_ERR, "Error while setting key: %s", ERR_error_string(ERR_get_error(), NULL));
 	return false;
 }
 
 bool cipher_set_key_from_rsa(cipher_t *cipher, void *key, size_t len, bool encrypt) {
-	memcpy(cipher->key, key + len - (size_t)cipher->keylen, cipher->keylen);
-	memcpy(cipher->key + cipher->keylen, key + len - (size_t)cipher->keylen - (size_t)cipher->blklen, cipher->blklen);
 	bool result;
 
 	if(encrypt)
-		result = EVP_EncryptInit_ex(&cipher->ctx, cipher->cipher, NULL, (unsigned char *)cipher->key, (unsigned char *)cipher->key + cipher->keylen);
+		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);
 	else
-		result = EVP_DecryptInit_ex(&cipher->ctx, cipher->cipher, NULL, (unsigned char *)cipher->key, (unsigned char *)cipher->key + cipher->keylen);
+		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);
 
 	if(result)
 		return true;
 
-	logger(LOG_ERR, "Error while setting key: %s", ERR_error_string(ERR_get_error(), NULL));
+	logger(DEBUG_ALWAYS, LOG_ERR, "Error while setting key: %s", ERR_error_string(ERR_get_error(), NULL));
 	return false;
 }
 
-bool cipher_regenerate_key(cipher_t *cipher, bool encrypt) {
-	bool result;
+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();
+	}
 
-	RAND_pseudo_bytes((unsigned char *)cipher->key, cipher->keylen + cipher->blklen);
+	memcpy(cipher->counter->counter + cipher->cipher->block_size - len, counter, len);
+	memset(cipher->counter->counter, 0, 4);
+	cipher->counter->n = 0;
 
-	if(encrypt)
-		result = EVP_EncryptInit_ex(&cipher->ctx, cipher->cipher, NULL, (unsigned char *)cipher->key, (unsigned char *)cipher->key + cipher->keylen);
+	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 = xmalloc_and_zero(sizeof *cipher->counter);
 	else
-		result = EVP_DecryptInit_ex(&cipher->ctx, cipher->cipher, NULL, (unsigned char *)cipher->key, (unsigned char *)cipher->key + cipher->keylen);
+		cipher->counter->n = 0;
 
-	if(result)
-		return true;
-	
-	logger(LOG_ERR, "Error while regenerating key: %s", ERR_error_string(ERR_get_error(), NULL));
-	return false;
+	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 = *outlen, pad;
+		int len, pad;
 		if(EVP_EncryptInit_ex(&cipher->ctx, NULL, NULL, NULL, NULL)
-				&&EVP_EncryptUpdate(&cipher->ctx, outdata, &len, indata, inlen)
-				&& EVP_EncryptFinal(&cipher->ctx, outdata + len, &pad)) {
-			*outlen = len + pad;
+				&& 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 = *outlen;
+		int len;
 		if(EVP_EncryptUpdate(&cipher->ctx, outdata, &len, indata, inlen)) {
-			*outlen = len;
+			if(outlen) *outlen = len;
 			return true;
 		}
 	}
 
-	logger(LOG_ERR, "Error while encrypting: %s", ERR_error_string(ERR_get_error(), NULL));
+	logger(DEBUG_ALWAYS, LOG_ERR, "Error while encrypting: %s", ERR_error_string(ERR_get_error(), NULL));
 	return false;
 }
 
 bool cipher_decrypt(cipher_t *cipher, const void *indata, size_t inlen, void *outdata, size_t *outlen, bool oneshot) {
 	if(oneshot) {
-		int len = *outlen, pad;
+		int len, pad;
 		if(EVP_DecryptInit_ex(&cipher->ctx, NULL, NULL, NULL, NULL)
-				&& EVP_DecryptUpdate(&cipher->ctx, outdata, &len, indata, inlen)
-				&& EVP_DecryptFinal(&cipher->ctx, outdata + len, &pad)) {
-			*outlen = len + pad;
+				&& 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 = *outlen;
+		int len;
 		if(EVP_EncryptUpdate(&cipher->ctx, outdata, &len, indata, inlen)) {
-			*outlen = len;
+			if(outlen) *outlen = len;
 			return true;
 		}
 	}
 
-	logger(LOG_ERR, "Error while encrypting: %s", ERR_error_string(ERR_get_error(), NULL));
+	logger(DEBUG_ALWAYS, LOG_ERR, "Error while decrypting: %s", ERR_error_string(ERR_get_error(), NULL));
 	return false;
 }