Add trinary and input validators. (#13)

* added trits/trytes validations.

* Added input validators.

* fixed code style and typo.

* Added test_is_address_with_checksum.

common/model/transaction.h

@@ -35,6 +35,7 @@ extern "C" {
 #define NUM_TRITS_ATTACHMENT_TIMESTAMP_UPPER 27
 #define NUM_TRITS_NONCE 81
 #define NUM_TRITS_HASH 243
+#define NUM_TRITS_CHECKSUM 27
 
 #define NUM_TRYTES_SERIALIZED_TRANSACTION 2673
 #define NUM_TRYTES_SIGNATURE 2187
@@ -54,6 +55,7 @@ extern "C" {
 #define NUM_TRYTES_ATTACHMENT_TIMESTAMP_UPPER 9
 #define NUM_TRYTES_NONCE 27
 #define NUM_TRYTES_HASH 81
+#define NUM_TRYTES_CHECKSUM 9
 
 #define NUM_FLEX_TRITS_SERIALIZED_TRANSACTION FLEX_TRIT_SIZE_8019
 #define NUM_FLEX_TRITS_SIGNATURE FLEX_TRIT_SIZE_6561
@@ -73,6 +75,7 @@ extern "C" {
 #define NUM_FLEX_TRITS_ATTACHMENT_TIMESTAMP_UPPER FLEX_TRIT_SIZE_27
 #define NUM_FLEX_TRITS_NONCE FLEX_TRIT_SIZE_81
 #define NUM_FLEX_TRITS_HASH FLEX_TRIT_SIZE_243
+#define NUM_FLEX_TRITS_CHECKSUM FLEX_TRIT_SIZE_27
 
 // bundle essence = 486 trits
 #define NUM_TRITS_ESSENCE                                                                                         \

common/trinary/BUILD

@@ -10,6 +10,7 @@ cc_library(
 
 cc_library(
     name = "trits",
+    srcs = ["trits.c"],
     hdrs = ["trits.h"],
     deps = [
         "//common:stdint",
@@ -18,6 +19,7 @@ cc_library(
 
 cc_library(
     name = "tryte",
+    srcs = ["tryte.c"],
     hdrs = ["tryte.h"],
     deps = [
         "//common:stdint",

common/trinary/tests/BUILD

@@ -30,7 +30,7 @@ cc_test(
 )
 
 cc_test(
-    name = "test_tryte",
+    name = "test_trit_tryte",
     timeout = "short",
     srcs = ["test_trit_tryte.c"],
     deps = [
@@ -88,3 +88,23 @@ cc_test(
         "@unity",
     ],
 )
+
+cc_test(
+    name = "test_trits",
+    timeout = "short",
+    srcs = ["test_trits.c"],
+    deps = [
+        "//common/trinary:trits",
+        "@unity",
+    ],
+)
+
+cc_test(
+    name = "test_tryte",
+    timeout = "short",
+    srcs = ["test_tryte.c"],
+    deps = [
+        "//common/trinary:tryte",
+        "@unity",
+    ],
+)

common/trinary/tests/test_trits.c

@@ -0,0 +1,57 @@
+/*
+ * Copyright (c) 2020 IOTA Stiftung
+ * https://github.com/iotaledger/iota_common
+ *
+ * Refer to the LICENSE file for licensing information
+ */
+
+#include <stdio.h>
+#include <unity/unity.h>
+
+#include "common/trinary/trits.h"
+
+void test_is_trits(void) {
+  const trit_t tryte_LUT[27][3] = {
+      {0, 0, 0},  {1, 0, 0},  {-1, 1, 0},  {0, 1, 0},  {1, 1, 0},  {-1, -1, 1},  {0, -1, 1},  {1, -1, 1},  {-1, 0, 1},
+      {0, 0, 1},  {1, 0, 1},  {-1, 1, 1},  {0, 1, 1},  {1, 1, 1},  {-1, -1, -1}, {0, -1, -1}, {1, -1, -1}, {-1, 0, -1},
+      {0, 0, -1}, {1, 0, -1}, {-1, 1, -1}, {0, 1, -1}, {1, 1, -1}, {-1, -1, 0},  {0, -1, 0},  {1, -1, 0},  {-1, 0, 0}};
+
+  for (size_t i = 0; i < 27; i++) {
+    printf("tryte LUT checking %ld\n", i);
+    TEST_ASSERT(is_trits(tryte_LUT[i], 3) == true);
+  }
+
+  const trit_t ng_tryte[6][3] = {{2, 0, 0}, {1, 3, 0}, {-1, 1, 4}, {-2, 1, 0}, {1, -3, 0}, {-1, -1, -4}};
+  for (size_t i = 0; i < 6; i++) {
+    printf("ng_tryte checking %ld\n", i);
+    TEST_ASSERT(is_trits(ng_tryte[i], 3) == false);
+  }
+
+  const trit_t trytes_LUT[14][6] = {{0, 0, 0, 1, 0, 0},   {-1, 1, 0, 0, 1, 0},     {1, 1, 0, -1, -1, 1},
+                                    {0, -1, 1, 1, -1, 1}, {-1, 0, 1, 0, 0, 1},     {1, 0, 1, -1, 1, 1},
+                                    {0, 1, 1, 1, 1, 1},   {-1, -1, -1, 0, -1, -1}, {1, -1, -1, -1, 0, -1},
+                                    {0, 0, -1, 1, 0, -1}, {-1, 1, -1, 0, 1, -1},   {1, 1, -1, -1, -1, 0},
+                                    {0, -1, 0, 1, -1, 0}, {-1, 0, 0, 1, 1, 1}};
+  for (size_t i = 0; i < 14; i++) {
+    printf("trytes LUT checking %ld\n", i);
+    TEST_ASSERT(is_trits(trytes_LUT[i], 6) == true);
+  }
+
+  const trit_t ng_trytes[14][6] = {{2, 0, 0, 1, 0, 0},    {-1, 3, 0, 0, 1, 0},     {1, 1, 4, -1, -1, 1},
+                                   {0, -1, 1, 5, -1, 1},  {-1, 0, 1, 0, 6, 1},     {1, 0, 1, -1, 1, 7},
+                                   {-2, 1, 1, 1, 1, 1},   {-1, -3, -1, 0, -1, -1}, {1, -1, -4, -1, 0, -1},
+                                   {0, 0, -1, -5, 0, -1}, {-1, 1, -1, 0, -6, -1},  {1, 1, -1, -1, -1, -7},
+                                   {0, -1, 0, 1, -10, 0}, {-1, 10, 0, 1, 1, 1}};
+  for (size_t i = 0; i < 14; i++) {
+    printf("ng_trytes LUT checking %ld\n", i);
+    TEST_ASSERT(is_trits(ng_trytes[i], 6) == false);
+  }
+}
+
+int main(void) {
+  UNITY_BEGIN();
+
+  RUN_TEST(test_is_trits);
+
+  return UNITY_END();
+}

common/trinary/tests/test_tryte.c

@@ -0,0 +1,34 @@
+/*
+ * Copyright (c) 2020 IOTA Stiftung
+ * https://github.com/iotaledger/iota_common
+ *
+ * Refer to the LICENSE file for licensing information
+ */
+
+#include <stdio.h>
+#include <unity/unity.h>
+
+#include "common/trinary/tryte.h"
+
+void test_is_trytes() {
+  tryte_t *hash0 = (tryte_t *)"XUERGHWTYRTFUYKFKXURKHMFEVLOIFTTCNTXOGLDPCZ9CJLKHROOPGNAQYFJEPGK9OKUQROUECBAVNXRX";
+  TEST_ASSERT(is_trytes(hash0, 81) == true);
+  // length is unmatched
+  TEST_ASSERT(is_trytes(hash0, 20) == false);
+
+  // hash with lowercases
+  tryte_t *hash1 = (tryte_t *)"XUERGHWTYRTFUYKFKXURKHMFEVLOIFTTCNTXOGLDPCZ9cjlkhroopgnaqyfjepgk9okuqrouecbavnxrx";
+  TEST_ASSERT(is_trytes(hash1, 81) == false);
+
+  // hash with invalid tryte
+  tryte_t *hash2 = (tryte_t *)"XUERGH3TYRTFUYKFKXURKHMF5VLOIFTTCNTXOGLDPCZ9CJLKHR0OPGNAQYFJEPGK9OKUQROUECBAVNXRX";
+  TEST_ASSERT(is_trytes(hash2, 81) == false);
+}
+
+int main(void) {
+  UNITY_BEGIN();
+
+  RUN_TEST(test_is_trytes);
+
+  return UNITY_END();
+}

common/trinary/trits.c

@@ -0,0 +1,17 @@
+/*
+ * Copyright (c) 2020 IOTA Stiftung
+ * https://github.com/iotaledger/iota_common
+ *
+ * Refer to the LICENSE file for licensing information
+ */
+
+#include "common/trinary/trits.h"
+
+bool is_trits(trit_t const *const trits, size_t len) {
+  for (size_t i = 0; i < len; i++) {
+    if (trits[i] < -1 || trits[i] > 1) {
+      return false;
+    }
+  }
+  return true;
+}

common/trinary/trits.h

@@ -8,8 +8,27 @@
 #ifndef __COMMON_TRINARY_TRIT_H_
 #define __COMMON_TRINARY_TRIT_H_
 
+#include <stdbool.h>
+
 #include "common/stdint.h"
 
 typedef int8_t trit_t;
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * @brief Checks if the given trits are valid.
+ *
+ * @param[in] trits A trits array.
+ * @param[in] len The length of trits array.
+ * @return boolean
+ */
+bool is_trits(trit_t const* const trits, size_t len);
+
+#ifdef __cplusplus
+}
+#endif
+
 #endif  // __COMMON_TRINARY_TRIT_H_

common/trinary/tryte.c

@@ -0,0 +1,25 @@
+/*
+ * Copyright (c) 2020 IOTA Stiftung
+ * https://github.com/iotaledger/iota_common
+ *
+ * Refer to the LICENSE file for licensing information
+ */
+
+#include <string.h>
+
+#include "common/trinary/tryte.h"
+
+bool is_trytes(tryte_t const *const trytes, size_t len) {
+  size_t trytes_cnt = strlen((char *)trytes);
+  if (trytes_cnt != len) {
+    // length does not match.
+    return false;
+  }
+
+  for (size_t i = 0; i < len; i++) {
+    if (trytes[i] != '9' && (trytes[i] < 'A' || trytes[i] > 'Z')) {
+      return false;
+    }
+  }
+  return true;
+}

common/trinary/tryte.h

@@ -8,10 +8,29 @@
 #ifndef __COMMON_TRINARY_TRYTE_H_
 #define __COMMON_TRINARY_TRYTE_H_
 
+#include <stdbool.h>
+
 #include "common/stdint.h"
 
 typedef int8_t tryte_t;
 
 #define INDEX_OF_TRYTE(tryte) ((tryte) == '9' ? 0 : ((tryte) - 'A' + 1))
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * @brief Checks if given trytes are valid.
+ *
+ * @param[in] trytes A string of trytes.
+ * @param[in] len The length of the string.
+ * @return boolean
+ */
+bool is_trytes(tryte_t const *const trytes, size_t len);
+
+#ifdef __cplusplus
+}
+#endif
+
 #endif  // __COMMON_TRINARY_TRYTE_H_

utils/BUILD

@@ -115,3 +115,14 @@ cc_library(
     hdrs = ["char_buffer.h"],
     deps = ["//common:errors"],
 )
+
+cc_library(
+    name = "input_validators",
+    srcs = ["input_validators.c"],
+    hdrs = ["input_validators.h"],
+    deps = [
+        "//common/model:transaction",
+        "//common/trinary:trits",
+        "//common/trinary:tryte",
+    ],
+)

utils/input_validators.c

@@ -0,0 +1,36 @@
+/*
+ * Copyright (c) 2020 IOTA Stiftung
+ * https://github.com/iotaledger/iota_common
+ *
+ * Refer to the LICENSE file for licensing information
+ */
+
+#include "utils/input_validators.h"
+#include "common/model/transaction.h"
+
+bool is_tryte_with_trailing_zero(tryte_t const tryte) {
+  if (tryte == '9' || (tryte >= 'A' && tryte <= 'D') || (tryte >= 'W' && tryte <= 'Z')) {
+    return true;
+  }
+  return false;
+}
+
+bool is_address(tryte_t const *const address) {
+  if (is_trytes(address, NUM_TRYTES_ADDRESS)) {
+    return is_tryte_with_trailing_zero(address[NUM_TRYTES_ADDRESS - 1]);
+  }
+  return false;
+}
+
+bool is_address_with_checksum(tryte_t const *const address) {
+  if (is_trytes(address, NUM_TRYTES_ADDRESS + NUM_TRYTES_CHECKSUM)) {
+    return is_tryte_with_trailing_zero(address[NUM_TRYTES_ADDRESS - 1]);
+  }
+  return false;
+}
+
+bool is_tag(tryte_t const *const tag) { return is_trytes(tag, NUM_TRYTES_TAG); }
+
+bool is_seed(tryte_t const *const seed) { return is_trytes(seed, NUM_TRYTES_HASH); }
+
+bool is_security_level(uint8_t level) { return (level >= 1 && level <= 3); }

utils/input_validators.h

@@ -0,0 +1,78 @@
+/*
+ * Copyright (c) 2020 IOTA Stiftung
+ * https://github.com/iotaledger/iota_common
+ *
+ * Refer to the LICENSE file for licensing information
+ */
+
+#ifndef __INPUT_VALIDATORS_H__
+#define __INPUT_VALIDATORS_H__
+
+#include <stdbool.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "common/trinary/trits.h"
+#include "common/trinary/tryte.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * @brief Checks if a tryte with a trailing zero trit.
+ *
+ * @param[in] tryte A tryte
+ * @return boolean
+ */
+bool is_tryte_with_trailing_zero(tryte_t const tryte);
+
+/**
+ * @brief Checks if the given address is valid.
+ *
+ * An address should be 81 trytes with a zero-trit at tail.
+ *
+ * @param[in] address A hash string.
+ * @return boolean
+ */
+bool is_address(tryte_t const* const address);
+
+/**
+ * @brief Checks if address hash contains checksum
+ *
+ * It won't validate checksum, checks the hash length only.
+ *
+ * @param[in] address A hash string.
+ * @return boolean
+ */
+bool is_address_with_checksum(tryte_t const* const address);
+
+/**
+ * @brief Checks if the given hash is a tag.
+ *
+ * @param[in] tag A hash string.
+ * @return boolean
+ */
+bool is_tag(tryte_t const* const tag);
+
+/**
+ * @brief Checks if the given hash is a seed.
+ *
+ * @param[in] seed A hash string.
+ * @return boolean
+ */
+bool is_seed(tryte_t const* const seed);
+
+/**
+ * @brief Checks if the given number is a security level.
+ *
+ * @param[in] level An integer.
+ * @return boolean
+ */
+bool is_security_level(uint8_t level);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif  // __INPUT_VALIDATORS_H__