Use EVP_CIPHER_CTX version of AES from openssl, so openssl can use engines (if they exist). (2999cbf2) · Commits · The Tor Project / Core / Tor

doc/TODO

+5 −2

Original line number	Diff line number	Diff line
		@@ -41,7 +41,7 @@ R - are dirservers auto-verifying duplicate nicknames?
		(with the new smartlist sort stuff maybe)
		o setconf SocksBindAddress kills tor if it fails to bind

		N - controller libs should support resetconf command.
		o controller libs should support resetconf command.
		N . Additional controller features
		- Find a way to make event info more extensible
		- change circuit status events to give more details, like purpose,
		@@ -97,7 +97,10 @@ N - warn if listening for SOCKS on public IP.
		- cpu fixes:
		- see if we should make use of truncate to retry
		o hardware accelerator support (configure engines.)
		- hardware accelerator support (use instead of aes.c when reasonable)
		o hardware accelerator support (use instead of aes.c when reasonable)
		- Benchmark this somehow to see whether using EVP_foo is slower in the
		non-engine case than AES_foo. If so, check for AES engine and fall
		back to AES_foo when it's not found.
		R - kill dns workers more slowly

		. Directory changes

src/common/aes.c

+37 −4

Original line number	Diff line number	Diff line
		@@ -20,12 +20,23 @@ const char aes_c_id[] = "$Id$";
		#include <string.h>
		#include "aes.h"
		#include "util.h"
		#include "log.h"

		/* Use OpenSSL's AES if we're running 0.9.7 or later. (The f at the end of
		* the version below means "release"; see opensslv.h) */
		#if OPENSSL_VERSION_NUMBER >= 0x0090700fl
		#define USE_OPENSSL_AES
		#include <openssl/aes.h>
		#include <openssl/evp.h>
		#endif

		/* For now, if OpenSSL supports AES, we always use the EVP_CIPHER_CTX version
		* of it, so OpenSSL can use an engine instead if available. If the overhead
		* turns out to suck, we should maybe switch to use OpenSSL's AES directly
		* when no engine exists.
		*/
		#ifdef USE_OPENSSL_AES
		#define USE_OPENSSL_EVP
		#endif

		/======================================================================/
		@@ -48,7 +59,9 @@ static void rijndaelEncrypt(const u32 rk[/4(Nr + 1)*/], int Nr, const u8 pt[16
		/* Interface to AES code, and counter implementation */

		struct aes_cnt_cipher {
		#ifdef USE_OPENSSL_AES
		#if defined(USE_OPENSSL_EVP)
		EVP_CIPHER_CTX key;
		#elif defined(USE_OPENSSL_AES)
		AES_KEY key;
		#else
		u32 rk[4*(MAXNR+1)];
		@@ -67,6 +80,12 @@ struct aes_cnt_cipher {
		static void
		_aes_fill_buf(aes_cnt_cipher_t *cipher)
		{
		/* We don't currently use OpenSSL's counter mode implementation because:
		* 1) some versions have known bugs
		* 2) its attitude towards IVs is not our own
		* 3) changing the counter position was not trivial, last time I looked.
		* None of these issues are insurmountable in principle.
		*/
		u32 counter0 = cipher->counter0;
		u32 counter1 = cipher->counter1;
		u8 buf[16];
		@@ -80,8 +99,13 @@ _aes_fill_buf(aes_cnt_cipher_t *cipher)
		buf[ 9] = (counter1 >> 16) & 0xff;
		buf[ 8] = (counter1 >> 24) & 0xff;

		#ifdef USE_OPENSSL_AES
		AES_encrypt(buf, cipher->buf, &(cipher->key));
		#if defined(USE_OPENSSL_EVP)
		{
		int outl=16, inl=16;
		EVP_EncryptUpdate(&cipher->key, cipher->buf, &outl, buf, inl);
		}
		#elif defined(USE_OPENSSL_AES)
		AES_encrypt(buf, cipher->buf, &cipher->key);
		#else
		rijndaelEncrypt(cipher->rk, cipher->nr, buf, cipher->buf);
		#endif
		@@ -105,7 +129,16 @@ aes_new_cipher()
		void
		aes_set_key(aes_cnt_cipher_t cipher, const char key, int key_bits)
		{
		#ifdef USE_OPENSSL_AES
		#if defined(USE_OPENSSL_EVP)
		const EVP_CIPHER *c;
		switch (key_bits) {
		case 128: c = EVP_aes_128_ecb(); break;
		case 192: c = EVP_aes_192_ecb(); break;
		case 256: c = EVP_aes_256_ecb(); break;
		default: tor_assert(0);
		}
		EVP_EncryptInit(&cipher->key, c, (const unsigned char*)key, NULL);
		#elif defined(USE_OPENSSL_AES)
		AES_set_encrypt_key((const unsigned char *)key, key_bits, &(cipher->key));
		#else
		cipher->nr = rijndaelKeySetupEnc(cipher->rk, (const unsigned char*)key,