libswarm-ng

commit 8fc4cf4afebe363c8023b00b7e2cae18d15b5a2d
parent 8a04c7dc23a9055155489ddbd6cc69c785d42d47
Author: nolash <dev@holbrook.no>
Date:   Sun, 12 Sep 2021 10:35:46 +0200

Split init and sum, add length prefix

Diffstat:
M
Makefile.dev
 | 
8
++++----
M
src/bmt.c
 | 
49
+++++++++++++++++++++++++++++++++++++------------
M
src/bmt.h
 | 
8
++++----
M
src/endian.c
 | 
2
+-
M
test/check_bmt.c
 | 
21
+++++++++++++++++----

5 files changed, 63 insertions(+), 25 deletions(-)
diff --git a/Makefile.dev b/Makefile.dev
@@ -1,12 +1,12 @@
 export LD_LIBRARY_PATH
 
 build:
-	mkdir -p build lib
-	gcc -I./src -c -o lib/bmt.o src/bmt.c $(CFLAGS) -lkeccak
-	gcc -I./src -c -o lib/endian.o $(CFLAGS) src/endian.c
+	mkdir -p build
+	gcc -I./src -c -o build/bmt.o src/bmt.c $(CFLAGS) -lkeccak
+	gcc -I./src -c -o build/endian.o $(CFLAGS) src/endian.c
 
 build_test: build
-	gcc -I./src -o test/check_bmt lib/*.o test/check_bmt.c $(CFLAGS) -lcheck -lkeccak
+	gcc -I./src -o test/check_bmt build/*.o test/check_bmt.c $(CFLAGS) -lcheck -lkeccak
 
 .PHONY: test
 
diff --git a/src/bmt.c b/src/bmt.c
@@ -3,33 +3,58 @@
 #include <XKCP/KeccakHash.h>
 #include <XKCP/KangarooTwelve.h>
 #include <XKCP/SP800-185.h>
+#include "endian.h"
 
 #include "bmt.h"
 
-#define DIGEST_INPUT_SIZE WORD_SIZE * 2
+#define _DIGEST_INPUT_SIZE _WORD_SIZE * 2
+#define _ROLLUP_TARGET BLOCK_SIZE + _DATA_LENGTH_TYPESIZE + _WORD_SIZE
+
 
 static int bmt_rollup(bmt_t *bmt_content) {
-	while (bmt_content->ptr != bmt_content->target) {
-		Keccak_HashInstance instance;
-		if (Keccak_HashInitialize(&instance, 1088, 512, 256, 0x01)) {
-			return 1;
+	char *last_target = bmt_content->ptr + _WORD_SIZE;
+
+	while (last_target != 0x00) {
+		while (bmt_content->ptr != bmt_content->target) {
+			Keccak_HashInstance instance;
+			if (Keccak_HashInitialize(&instance, 1088, 512, 256, 0x01)) {
+				return 1;
+			}
+			Keccak_HashUpdate(&instance, bmt_content->ptr, _DIGEST_INPUT_SIZE);
+			Keccak_HashFinal(&instance, bmt_content->ptr);
+			bmt_content->ptr += _DIGEST_INPUT_SIZE;
+		}
+		bmt_content->target = (bmt_content->target - bmt_content->ptr) / 2;
+		if (bmt_content->target < last_target) {
+			last_target = 0x00;
 		}
-		Keccak_HashUpdate(&instance, bmt_content->ptr, DIGEST_INPUT_SIZE);
-		Keccak_HashFinal(&instance, bmt_content->ptr);
 	}
+
+	Keccak_HashInstance instance;
+	if (Keccak_HashInitialize(&instance, 1088, 512, 256, 0x01)) {
+		return 1;
+	}
+	Keccak_HashUpdate(&instance, bmt_content->buf, _DATA_LENGTH_TYPESIZE + _WORD_SIZE);
+	Keccak_HashFinal(&instance, bmt_content->buf);
+
+	return 0;
 }
 
+
 void bmt_init(bmt_t *bmt_content, char *input, size_t input_length, long long data_length) {
-	bmt_content->ptr = (char*)bmt_content->buf+8;
+	bmt_content->ptr = (char*)bmt_content->buf+_DATA_LENGTH_TYPESIZE;
 	bmt_content->target = bmt_content->ptr + BLOCK_SIZE;
-	memset(bmt_content->ptr, 0, BLOCK_SIZE);
+	memset(bmt_content->buf, 0, BLOCK_SIZE+_DATA_LENGTH_TYPESIZE);
+
+	memcpy((char*)bmt_content->buf, &data_length, sizeof(long long));
+	to_endian(CONVERT_BIGENDIAN, _DATA_LENGTH_TYPESIZE, bmt_content->buf);
+
 	memcpy(bmt_content->ptr, input, input_length);
 }
 
-int bmt_sum(bmt_t *bmt_content, char *input, size_t input_length, long long data_length) {
-	bmt_init(bmt_content, input, input_length, data_length);
+
+int bmt_sum(bmt_t *bmt_content) {
 	return bmt_rollup(bmt_content);
-	return 0;
 }
 
 
diff --git a/src/bmt.h b/src/bmt.h
@@ -2,16 +2,16 @@
 #define _LIBSWARM_BMT
 
 #define BLOCK_SIZE 4096
-#define WORD_SIZE 32
+#define _WORD_SIZE 32
+#define _DATA_LENGTH_TYPESIZE 8
 
 typedef struct bmt {
-	char buf[BLOCK_SIZE + 8];
+	char buf[BLOCK_SIZE + _DATA_LENGTH_TYPESIZE];
 	char *ptr;
 	char *target;
-	long long data_length;
 } bmt_t;	
 
 void bmt_init(bmt_t *bmt_content, char *input, size_t input_length, long long data_length);
-int bmt_sum(bmt_t *bmt_content, char *input, size_t input_length, long long data_length);
+int bmt_sum(bmt_t *bmt_content);
 
 #endif // _LIBSWARM_BMT
diff --git a/src/endian.c b/src/endian.c
@@ -5,7 +5,7 @@ int is_le() {
 	return *((unsigned char*)&s) == 42;
 }
 
-// convert unsigned integer to little-endian representation
+// convert unsigned integer to the given endian representation
 int to_endian(char direction, int l, void *n) {
 	union le un;
 
diff --git a/test/check_bmt.c b/test/check_bmt.c
@@ -6,15 +6,27 @@
 
 START_TEST(check_bmt_init) {
 	bmt_t bmt_context;
-	char *data = "foo";
-	char data_length = 3;
+	char *input = "foo";
+	char input_length = 3;
+	char data_length_bytes[] = {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x03};
 	int r;
 	
-	bmt_init(&bmt_context, data, data_length, 3);
-	ck_assert_mem_eq(bmt_context.ptr, data, 3);
+	bmt_init(&bmt_context, input, input_length, 3);
+	ck_assert_mem_eq(bmt_context.buf, data_length_bytes, sizeof(long long));
+	ck_assert_mem_eq(bmt_context.ptr, input, 3);
 }
 END_TEST
 
+
+START_TEST(check_bmt_sum) {
+	bmt_t bmt_context;
+	char *input = "foo";
+	char input_length = 3;
+
+	bmt_init(&bmt_context, input, input_length, 3);
+	bmt_sum(&bmt_context);
+}
+
 Suite * common_suite(void) {
 	Suite *s;
 	TCase *tc;
@@ -22,6 +34,7 @@ Suite * common_suite(void) {
 	s = suite_create("bmt");
 	tc = tcase_create("core");
 	tcase_add_test(tc, check_bmt_init);
+	tcase_add_test(tc, check_bmt_sum);
 	suite_add_tcase(s, tc);
 
 	return s;