Variable Byte Integer reading tests.

.gitignore

@@ -1,11 +1,15 @@
+*.db
+*.gcda
+*.gcno
+*.exe
 *.o
+*.old
+*.pyc
 *.so
-*.exe
-*.db
+*.vglog
+
 c/*.test
 cpp/*.test
-*.pyc
-*.vglog
 
 build/
 
@@ -50,5 +54,9 @@ test/ssl/*.csr
 test/lib/c/*.test
 test/lib/cpp/*.test
 
+test/unit/coverage.info
+test/unit/mosq_test
+test/unit/out
+
 www/cache/
 __pycache__

lib/packet_datatypes.c

@@ -174,24 +174,30 @@ void packet__write_uint32(struct mosquitto__packet *packet, uint32_t word)
 }
 
 
-int packet__read_varint(struct mosquitto__packet *packet, int32_t *word, uint8_t *bytes)
+int packet__read_varint(struct mosquitto__packet *packet, int32_t *word, int8_t *bytes)
 {
  int i;
- int remaining_mult = 1;
  uint8_t byte;
-
- *word = 0;
- if(bytes) (*bytes) = 0;
+ int remaining_mult = 1;
+ int32_t lword = 0;
+ uint8_t lbytes = 0;
 
  for(i=0; i<4; i++){
  if(packet->pos < packet->remaining_length){
- if(bytes) (*bytes)++;
+ lbytes++;
  byte = packet->payload[packet->pos];
- *word += (byte & 127) * remaining_mult;
+ lword += (byte & 127) * remaining_mult;
  remaining_mult *= 128;
  packet->pos++;
  if((byte & 128) == 0){
- return MOSQ_ERR_SUCCESS;
+ if(lbytes > 1 && byte == 0){
+ /* Catch overlong encodings */
+ return MOSQ_ERR_PROTOCOL;
+ }else{
+ *word = lword;
+ if(bytes) (*bytes) = lbytes;
+ return MOSQ_ERR_SUCCESS;
+ }
  }
  }else{
  return MOSQ_ERR_PROTOCOL;

lib/packet_mosq.h

@@ -32,7 +32,7 @@ int packet__read_bytes(struct mosquitto__packet *packet, void *bytes, uint32_t c
 int packet__read_string(struct mosquitto__packet *packet, char **str, int *length);
 int packet__read_uint16(struct mosquitto__packet *packet, uint16_t *word);
 int packet__read_uint32(struct mosquitto__packet *packet, uint32_t *word);
-int packet__read_varint(struct mosquitto__packet *packet, int32_t *word, uint8_t *bytes);
+int packet__read_varint(struct mosquitto__packet *packet, int32_t *word, int8_t *bytes);
 
 void packet__write_byte(struct mosquitto__packet *packet, uint8_t byte);
 void packet__write_bytes(struct mosquitto__packet *packet, const void *bytes, uint32_t count);

test/Makefile

@@ -14,6 +14,7 @@ all : fake_user msgsps_pub msgsps_sub
 test :
  $(MAKE) -C broker test
  $(MAKE) -C lib test
+ $(MAKE) -C unit test
 
 ptest :
  $(MAKE) -C broker ptest

test/unit/Makefile

@@ -0,0 +1,27 @@
+include ../../config.mk
+
+.PHONY: all test clean coverage
+
+CFLAGS=-I../.. -I../../lib -coverage
+TEST_LDFLAGS=-lcunit -coverage
+
+all : test
+
+packet_datatypes.o : ../../lib/packet_datatypes.c
+ $(CROSS_COMPILE)$(CC) $(CFLAGS) -c -o $@ $^
+
+memory_mosq.o : ../../lib/memory_mosq.c
+ $(CROSS_COMPILE)$(CC) $(CFLAGS) -c -o $@ $^
+
+mosq_test : test.o datatypes.o memory_mosq.o packet_datatypes.o
+ $(CROSS_COMPILE)$(CC) -o $@ $^ ${TEST_LDFLAGS}
+
+test : mosq_test
+ ./mosq_test
+
+clean : 
+ -rm -f test *.o
+
+coverage :
+ lcov --capture --directory . --output-file coverage.info
+ genhtml coverage.info --output-directory out

test/unit/datatypes.c

@@ -0,0 +1,259 @@
+#include <CUnit/CUnit.h>
+#include <CUnit/Basic.h>
+
+#include "packet_mosq.h"
+
+static void varint_read_helper(
+ uint8_t *payload,
+ int remaining_length,
+ int rc_expected,
+ int32_t value_expected,
+ int8_t bytes_expected)
+{
+ struct mosquitto__packet packet;
+ int32_t value = -1;
+ int8_t bytes = -1;
+ int rc;
+
+ memset(&packet, 0, sizeof(struct mosquitto__packet));
+ packet.payload = payload;
+ packet.remaining_length = remaining_length;
+ rc = packet__read_varint(&packet, &value, &bytes);
+ CU_ASSERT_EQUAL(rc, rc_expected);
+ CU_ASSERT_EQUAL(value, value_expected);
+ CU_ASSERT_EQUAL(bytes, bytes_expected);
+}
+
+
+/* This tests reading a Variable Byte Integer from an incoming packet.
+ *
+ * It tests:
+ * * Empty packet
+ */
+static void TEST_varint_read_empty(void)
+{
+ struct mosquitto__packet packet;
+ int rc;
+
+ /* Empty packet */
+ varint_read_helper(NULL, 0, MOSQ_ERR_PROTOCOL, -1, -1);
+}
+
+
+/* This tests reading a Variable Byte Integer from an incoming packet.
+ *
+ * It tests:
+ * * Truncated packets (varint encoding is longer than data)
+ */
+static void TEST_varint_read_truncated(void)
+{
+ struct mosquitto__packet packet;
+ uint8_t payload[20];
+ int rc;
+
+ /* Varint bigger than packet */
+ memset(payload, 0, sizeof(payload));
+ payload[0] = 0x80;
+ varint_read_helper(payload, 1, MOSQ_ERR_PROTOCOL, -1, -1);
+
+ /* Varint bigger than packet */
+ memset(payload, 1, sizeof(payload));
+ payload[0] = 0x80;
+ payload[1] = 0x80;
+ varint_read_helper(payload, 2, MOSQ_ERR_PROTOCOL, -1, -1);
+
+ /* Varint bigger than packet */
+ memset(payload, 0, sizeof(payload));
+ payload[0] = 0x80;
+ payload[1] = 0x80;
+ payload[2] = 0x80;
+ varint_read_helper(payload, 3, MOSQ_ERR_PROTOCOL, -1, -1);
+
+ /* Varint bigger than packet */
+ memset(payload, 0, sizeof(payload));
+ payload[0] = 0x80;
+ payload[1] = 0x80;
+ payload[2] = 0x80;
+ payload[3] = 0x80;
+ varint_read_helper(payload, 4, MOSQ_ERR_PROTOCOL, -1, -1);
+}
+
+
+/* This tests reading a Variable Byte Integer from an incoming packet.
+ *
+ * It tests:
+ * * Correct values on boundaries of 1, 2, 3, 4 byte encodings
+ */
+static void TEST_varint_read_boundaries(void)
+{
+ struct mosquitto__packet packet;
+ uint8_t payload[20];
+ int rc;
+
+ /* Value = 0 */
+ memset(payload, 0, sizeof(payload));
+ payload[0] = 0x00;
+ varint_read_helper(payload, 1, MOSQ_ERR_SUCCESS, 0, 1);
+
+ /* Value = 127 (just beneath the crossover to two bytes */
+ memset(payload, 0, sizeof(payload));
+ payload[0] = 0x7F;
+ varint_read_helper(payload, 1, MOSQ_ERR_SUCCESS, 127, 1);
+
+ /* Value = 128 (just after the crossover to two bytes */
+ memset(payload, 0, sizeof(payload));
+ packet.payload = payload;
+ payload[0] = 0x80;
+ payload[1] = 0x01;
+ varint_read_helper(payload, 2, MOSQ_ERR_SUCCESS, 128, 2);
+
+ /* Value = 16383 (just before the crossover to three bytes */
+ memset(payload, 0, sizeof(payload));
+ packet.payload = payload;
+ payload[0] = 0xFF;
+ payload[1] = 0x7F;
+ varint_read_helper(payload, 2, MOSQ_ERR_SUCCESS, 16383, 2);
+
+ /* Value = 16384 (just after the crossover to three bytes */
+ memset(payload, 0, sizeof(payload));
+ packet.payload = payload;
+ payload[0] = 0x80;
+ payload[1] = 0x80;
+ payload[2] = 0x01;
+ varint_read_helper(payload, 3, MOSQ_ERR_SUCCESS, 16384, 3);
+
+ /* Value = 2,097,151 (just before the crossover to four bytes */
+ memset(payload, 0, sizeof(payload));
+ packet.payload = payload;
+ payload[0] = 0xFF;
+ payload[1] = 0xFF;
+ payload[2] = 0x7F;
+ varint_read_helper(payload, 3, MOSQ_ERR_SUCCESS, 2097151, 3);
+
+ /* Value = 2,097,152 (just after the crossover to four bytes */
+ memset(payload, 0, sizeof(payload));
+ packet.payload = payload;
+ payload[0] = 0x80;
+ payload[1] = 0x80;
+ payload[2] = 0x80;
+ payload[3] = 0x01;
+ varint_read_helper(payload, 4, MOSQ_ERR_SUCCESS, 2097152, 4);
+
+ /* Value = 268,435,455 (highest value allowed) */
+ memset(payload, 0, sizeof(payload));
+ packet.payload = payload;
+ payload[0] = 0xFF;
+ payload[1] = 0xFF;
+ payload[2] = 0xFF;
+ payload[3] = 0x7F;
+ varint_read_helper(payload, 4, MOSQ_ERR_SUCCESS, 268435455, 4);
+}
+
+/* This tests reading a Variable Byte Integer from an incoming packet.
+ *
+ * It tests:
+ * * Too long encoding (5 bytes)
+ */
+static void TEST_varint_read_5_bytes(void)
+{
+ struct mosquitto__packet packet;
+ uint8_t payload[20];
+ int rc;
+
+ /* Value = 268,435,456 (one higher than highest value allowed) */
+ memset(payload, 0, sizeof(payload));
+ packet.payload = payload;
+ payload[0] = 0x80;
+ payload[1] = 0x80;
+ payload[2] = 0x80;
+ payload[3] = 0x80;
+ payload[4] = 0x01;
+ varint_read_helper(payload, 5, MOSQ_ERR_PROTOCOL, -1, -1);
+}
+
+
+/* This tests reading a Variable Byte Integer from an incoming packet.
+ *
+ * It tests:
+ * * Overlong encodings (e.g. 2 bytes to encode "1")
+ */
+static void TEST_varint_read_overlong_encoding(void)
+{
+ struct mosquitto__packet packet;
+ uint8_t payload[20];
+ int rc;
+
+ /* Overlong encoding of 0 (1 byte value encoded as 2 bytes) */
+ memset(payload, 0, sizeof(payload));
+ packet.payload = payload;
+ payload[0] = 0x80;
+ payload[1] = 0x00;
+ varint_read_helper(payload, 2, MOSQ_ERR_PROTOCOL, -1, -1);
+
+ /* Overlong encoding of 127 (1 byte value encoded as 2 bytes) */
+ memset(payload, 0, sizeof(payload));
+ packet.payload = payload;
+ payload[0] = 0xFF;
+ payload[1] = 0x00;
+ varint_read_helper(payload, 2, MOSQ_ERR_PROTOCOL, -1, -1);
+
+ /* Overlong encoding of 128 (2 byte value encoded as 3 bytes) */
+ memset(payload, 0, sizeof(payload));
+ packet.payload = payload;
+ payload[0] = 0x80;
+ payload[1] = 0x81;
+ payload[2] = 0x00;
+ varint_read_helper(payload, 3, MOSQ_ERR_PROTOCOL, -1, -1);
+
+ /* Overlong encoding of 16,383 (2 byte value encoded as 3 bytes) */
+ memset(payload, 0, sizeof(payload));
+ packet.payload = payload;
+ payload[0] = 0xFF;
+ payload[1] = 0xFF;
+ payload[2] = 0x00;
+ varint_read_helper(payload, 3, MOSQ_ERR_PROTOCOL, -1, -1);
+
+ /* Overlong encoding of 16,384 (3 byte value encoded as 4 bytes) */
+ memset(payload, 0, sizeof(payload));
+ packet.payload = payload;
+ payload[0] = 0x80;
+ payload[1] = 0x80;
+ payload[2] = 0x81;
+ payload[3] = 0x00;
+ varint_read_helper(payload, 4, MOSQ_ERR_PROTOCOL, -1, -1);
+
+ /* Overlong encoding of 2,097,151 (3 byte value encoded as 4 bytes) */
+ memset(payload, 0, sizeof(payload));
+ packet.payload = payload;
+ payload[0] = 0xFF;
+ payload[1] = 0xFF;
+ payload[2] = 0xFF;
+ payload[3] = 0x00;
+ varint_read_helper(payload, 4, MOSQ_ERR_PROTOCOL, -1, -1);
+}
+
+
+int init_datatype_tests(void)
+{
+ CU_pSuite test_suite = NULL;
+
+ test_suite = CU_add_suite("datatypes", NULL, NULL);
+ if(!test_suite){
+ printf("Error adding CUnit test suite.\n");
+ return 1;
+ }
+
+ if(0
+ || !CU_add_test(test_suite, "Variable Byte Integer read (empty packet)", TEST_varint_read_empty)
+ || !CU_add_test(test_suite, "Variable Byte Integer read (truncated packets)", TEST_varint_read_truncated)
+ || !CU_add_test(test_suite, "Variable Byte Integer read (encoding boundaries)", TEST_varint_read_boundaries)
+ || !CU_add_test(test_suite, "Variable Byte Integer read (five byte encoding)", TEST_varint_read_5_bytes)
+ || !CU_add_test(test_suite, "Variable Byte Integer read (overlong encodings)", TEST_varint_read_overlong_encoding)
+ ){
+
+ printf("Error adding datatypes CUnit tests.\n");
+ return 1;
+ }
+
+ return 0;
+}