[test] Add speed tests for cipher algorithms

Signed-off-by: Michael Brown <mcb30@ipxe.org>

src/tests/aes_cbc_test.c

@@ -169,9 +169,21 @@ AES_CBC_TEST ( test_256,
  *
  */
 static void aes_cbc_test_exec ( void ) {
+	struct cipher_algorithm *cipher = &aes_cbc_algorithm;
 
+	/* Correctness tests */
 	aes_cbc_ok ( &test_128 );
 	aes_cbc_ok ( &test_256 );
+
+	/* Speed tests */
+	DBG ( "AES128 encryption required %ld cycles per byte\n",
+	      cbc_cost_encrypt ( cipher, test_128.key_len ) );
+	DBG ( "AES128 decryption required %ld cycles per byte\n",
+	      cbc_cost_decrypt ( cipher, test_128.key_len ) );
+	DBG ( "AES256 encryption required %ld cycles per byte\n",
+	      cbc_cost_encrypt ( cipher, test_256.key_len ) );
+	DBG ( "AES256 decryption required %ld cycles per byte\n",
+	      cbc_cost_decrypt ( cipher, test_256.key_len ) );
 }
 
 /** AES-in-CBC-mode self-test */

src/tests/cbc_test.c

@@ -29,9 +29,11 @@ FILE_LICENCE ( GPL2_OR_LATER );
 #undef NDEBUG
 
 #include <stdint.h>
+#include <stdlib.h>
 #include <string.h>
 #include <assert.h>
 #include <ipxe/crypto.h>
+#include <ipxe/profile.h>
 #include "cbc_test.h"
 
 /**
@@ -49,8 +51,8 @@ FILE_LICENCE ( GPL2_OR_LATER );
 int cbc_test_encrypt ( struct cipher_algorithm *cipher, const void *key,
 		       size_t key_len, const void *iv, const void *plaintext,
 		       const void *expected_ciphertext, size_t len ) {
-	uint8_t ctx[ cipher->ctxsize ];
+	uint8_t ctx[cipher->ctxsize];
-	uint8_t ciphertext[ len ];
+	uint8_t ciphertext[len];
 	int rc;
 
 	/* Initialise cipher */
@@ -80,8 +82,8 @@ int cbc_test_encrypt ( struct cipher_algorithm *cipher, const void *key,
 int cbc_test_decrypt ( struct cipher_algorithm *cipher, const void *key,
 		       size_t key_len, const void *iv, const void *ciphertext,
 		       const void *expected_plaintext, size_t len ) {
-	uint8_t ctx[ cipher->ctxsize ];
+	uint8_t ctx[cipher->ctxsize];
-	uint8_t plaintext[ len ];
+	uint8_t plaintext[len];
 	int rc;
 
 	/* Initialise cipher */
@@ -95,3 +97,75 @@ int cbc_test_decrypt ( struct cipher_algorithm *cipher, const void *key,
 	/* Verify result */
 	return ( memcmp ( plaintext, expected_plaintext, len ) == 0 );
 }
+
+/**
+ * Calculate CBC encryption or decryption cost
+ *
+ * @v cipher			Cipher algorithm
+ * @v key_len			Length of key
+ * @v op			Encryption or decryption operation
+ * @ret cost			Cost (in cycles per byte)
+ */
+static unsigned long cbc_cost ( struct cipher_algorithm *cipher,
+				size_t key_len,
+				void ( * op ) ( struct cipher_algorithm *cipher,
+						void *ctx, const void *src,
+						void *dst, size_t len ) ) {
+	static uint8_t random[8192]; /* Too large for stack */
+	uint8_t key[key_len];
+	uint8_t iv[cipher->blocksize];
+	uint8_t ctx[cipher->ctxsize];
+	union profiler profiler;
+	unsigned long long elapsed;
+	unsigned long cost;
+	unsigned int i;
+	int rc;
+
+	/* Fill buffer with pseudo-random data */
+	srand ( 0x1234568 );
+	for ( i = 0 ; i < sizeof ( random ) ; i++ )
+		random[i] = rand();
+	for ( i = 0 ; i < sizeof ( key ) ; i++ )
+		key[i] = rand();
+	for ( i = 0 ; i < sizeof ( iv ) ; i++ )
+		iv[i] = rand();
+
+	/* Initialise cipher */
+	rc = cipher_setkey ( cipher, ctx, key, key_len );
+	assert ( rc == 0 );
+	cipher_setiv ( cipher, ctx, iv );
+
+	/* Time operation */
+	profile ( &profiler );
+	op ( cipher, ctx, random, random, sizeof ( random ) );
+	elapsed = profile ( &profiler );
+
+	/* Round to nearest whole number of cycles per byte */
+	cost = ( ( elapsed + ( sizeof ( random ) / 2 ) ) / sizeof ( random ) );
+
+	return cost;
+}
+
+/**
+ * Calculate CBC encryption cost
+ *
+ * @v cipher			Cipher algorithm
+ * @v key_len			Length of key
+ * @ret cost			Cost (in cycles per byte)
+ */
+unsigned long cbc_cost_encrypt ( struct cipher_algorithm *cipher,
+				 size_t key_len ) {
+	return cbc_cost ( cipher, key_len, cipher_encrypt );
+}
+
+/**
+ * Calculate CBC decryption cost
+ *
+ * @v cipher			Cipher algorithm
+ * @v key_len			Length of key
+ * @ret cost			Cost (in cycles per byte)
+ */
+unsigned long cbc_cost_decrypt ( struct cipher_algorithm *cipher,
+				 size_t key_len ) {
+	return cbc_cost ( cipher, key_len, cipher_decrypt );
+}

src/tests/cbc_test.h

@@ -15,6 +15,10 @@ extern int cbc_test_decrypt ( struct cipher_algorithm *cipher, const void *key,
 			      size_t key_len, const void *iv,
 			      const void *ciphertext,
 			      const void *expected_plaintext, size_t len );
+extern unsigned long cbc_cost_encrypt ( struct cipher_algorithm *cipher,
+					size_t key_len );
+extern unsigned long cbc_cost_decrypt ( struct cipher_algorithm *cipher,
+					size_t key_len );
 
 /**
  * Report CBC encryption test result