Fixed FQDN hostname limit in minimal hostnport implementation (#1263)

CHANGELOG.md

@@ -196,6 +196,7 @@ The git repositories are hosted at the following sites:
 
 ### Fixed
 
+* Fixed FQDN hostname size in minimal hostnport implementation. (#1263)
 * Fixed segmentation fault in Schedule_Recalculate_PV() during application
   startup. (#1258)
 * Fixed the ReadRange-ACK of the Address_List property. (#1149)

src/bacnet/hostnport.c

@@ -11,7 +11,6 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <ctype.h>
-#include <math.h>
 #include "bacnet/hostnport.h"
 #include "bacnet/bacdcode.h"
 
@@ -441,6 +440,37 @@ int host_n_port_minimal_encode(
     return apdu_len;
 }
 
+/**
+ * @brief Encode a context encoded BACnetHostNPort_Minimal complex data type
+ * @param apdu - the APDU buffer, or NULL for length
+ * @param tag_number - context tag number to be encoded
+ * @param host - BACnetHostNPort_Minimal SEQUENCE
+ * @return length of the encoded APDU buffer
+ */
+int host_n_port_minimal_context_encode(
+    uint8_t *apdu, uint8_t tag_number, const BACNET_HOST_N_PORT_MINIMAL *host)
+{
+    int len = 0;
+    int apdu_len = 0;
+
+    if (host) {
+        len = encode_opening_tag(apdu, tag_number);
+        apdu_len += len;
+        if (apdu) {
+            apdu += len;
+        }
+        len = host_n_port_minimal_encode(apdu, host);
+        apdu_len += len;
+        if (apdu) {
+            apdu += len;
+        }
+        len = encode_closing_tag(apdu, tag_number);
+        apdu_len += len;
+    }
+
+    return apdu_len;
+}
+
 /**
  * @brief  Decode the BACnetHostAddress
  * @param apdu - the APDU buffer
@@ -694,7 +724,7 @@ void host_n_port_minimal_ip_init(
     const uint8_t *address,
     size_t address_len)
 {
-    unsigned i, imax;
+    uint8_t i, imax;
 
     if (host) {
         host->tag = BACNET_HOST_ADDRESS_TAG_IP_ADDRESS;
@@ -722,7 +752,7 @@ void host_n_port_minimal_ip_init(
 void host_n_port_minimal_hostname_init(
     BACNET_HOST_N_PORT_MINIMAL *host, uint16_t port, const char *hostname)
 {
-    unsigned i;
+    uint8_t i;
 
     if (host) {
         host->tag = BACNET_HOST_ADDRESS_TAG_NAME;
@@ -753,7 +783,7 @@ bool host_n_port_minimal_copy(
     BACNET_HOST_N_PORT_MINIMAL *dest, const BACNET_HOST_N_PORT_MINIMAL *src)
 {
     bool status = false;
-    int i;
+    uint8_t i;
 
     if (dest && src) {
         dest->tag = src->tag;
@@ -873,7 +903,7 @@ bool host_n_port_minimal_same(
     const BACNET_HOST_N_PORT_MINIMAL *src)
 {
     bool status = false;
-    int i;
+    uint8_t i;
 
     if (dst && src) {
         if (dst->tag == src->tag) {

src/bacnet/hostnport.h

@@ -42,6 +42,9 @@ typedef struct BACnetHostNPort {
 #define BACNET_HOST_ADDRESS_TAG_NONE 0
 #define BACNET_HOST_ADDRESS_TAG_IP_ADDRESS 1
 #define BACNET_HOST_ADDRESS_TAG_NAME 2
+/* RFC 1035 255-octet total limit and 63-octet label limit
+   including dots and null terminator */
+#define BACNET_HOST_NAME_MAX 255
 /* BACnetHostNPort with smaller RAM footprint using C datatypes */
 typedef struct BACnetHostNPort_Minimal {
     uint8_t tag;
@@ -51,13 +54,19 @@ typedef struct BACnetHostNPort_Minimal {
             uint8_t length;
         } ip_address;
         struct BACnetHostCharacterString {
-            char fqdn[256];
+            char fqdn[BACNET_HOST_NAME_MAX];
             uint8_t length;
         } name;
     } host;
     uint16_t port;
 } BACNET_HOST_N_PORT_MINIMAL;
 
+/* Structure to hold the host IP address and hostname for lookup */
+typedef struct BACnetHostAddressPair {
+    struct BACnetHostOctetString ip_address;
+    struct BACnetHostCharacterString name;
+} BACNET_HOST_ADDRESS_PAIR;
+
 /**
  *  BACnetBDTEntry ::= SEQUENCE {
  *      bbmd-address [0] BACnetHostNPort,
@@ -158,6 +167,11 @@ int host_n_port_minimal_decode(
     BACNET_ERROR_CODE *error_code,
     BACNET_HOST_N_PORT_MINIMAL *address);
 BACNET_STACK_EXPORT
+int host_n_port_minimal_context_encode(
+    uint8_t *apdu,
+    uint8_t tag_number,
+    const BACNET_HOST_N_PORT_MINIMAL *address);
+BACNET_STACK_EXPORT
 int host_n_port_minimal_context_decode(
     const uint8_t *apdu,
     uint32_t apdu_size,

test/bacnet/hostnport/src/main.c

@@ -83,6 +83,72 @@ static void test_HostNPortMinimal_Codec(void)
     }
 }
 
+#if defined(CONFIG_ZTEST_NEW_API)
+ZTEST(host_n_port_tests, test_HostNPortMinimalContext_Codec)
+#else
+static void test_HostNPortMinimalContext_Codec(void)
+#endif
+{
+    uint8_t apdu[MAX_APDU] = { 0 };
+    int len = 0, apdu_len = 0, null_len = 0, test_len = 0;
+    BACNET_HOST_N_PORT_MINIMAL test_data_1 = { 0 }, test_data_2 = { 0 };
+    uint8_t address[IP6_ADDRESS_MAX] = { 1, 2,  3,  4,  5,  6,  7,  8,
+                                         9, 10, 11, 12, 13, 14, 15, 16 };
+    uint16_t port = 0xBAC0;
+    uint8_t tag_number = 1;
+    BACNET_ERROR_CODE error_code = ERROR_CODE_SUCCESS;
+
+    /* test IP address */
+    host_n_port_minimal_ip_init(&test_data_1, port, address, sizeof(address));
+    null_len =
+        host_n_port_minimal_context_encode(NULL, tag_number, &test_data_1);
+    apdu_len =
+        host_n_port_minimal_context_encode(apdu, tag_number, &test_data_1);
+    zassert_equal(apdu_len, null_len, NULL);
+    zassert_true(apdu_len != BACNET_STATUS_ERROR, NULL);
+    null_len = host_n_port_minimal_context_decode(
+        apdu, apdu_len, tag_number, NULL, NULL);
+    test_len = host_n_port_minimal_context_decode(
+        apdu, apdu_len, tag_number, &error_code, &test_data_2);
+    zassert_equal(test_len, null_len, NULL);
+    zassert_equal(
+        apdu_len, test_len, "apdu_len=%d test_len=%d", apdu_len, test_len);
+    zassert_true(
+        host_n_port_minimal_same(&test_data_1, &test_data_2),
+        "test_data_1 != test_data_2");
+    while (test_len) {
+        test_len--;
+        len = host_n_port_minimal_context_decode(
+            apdu, test_len, tag_number, NULL, NULL);
+        zassert_true(len < 0, "len=%d test_len=%d", len, test_len);
+    }
+
+    /* test hostname */
+    host_n_port_minimal_hostname_init(&test_data_1, port, "bacnet.org");
+    null_len =
+        host_n_port_minimal_context_encode(NULL, tag_number, &test_data_1);
+    apdu_len =
+        host_n_port_minimal_context_encode(apdu, tag_number, &test_data_1);
+    zassert_equal(apdu_len, null_len, NULL);
+    zassert_true(apdu_len != BACNET_STATUS_ERROR, NULL);
+    null_len = host_n_port_minimal_context_decode(
+        apdu, apdu_len, tag_number, NULL, NULL);
+    test_len = host_n_port_minimal_context_decode(
+        apdu, apdu_len, tag_number, &error_code, &test_data_2);
+    zassert_equal(test_len, null_len, NULL);
+    zassert_equal(
+        apdu_len, test_len, "apdu_len=%d test_len=%d", apdu_len, test_len);
+    zassert_true(
+        host_n_port_minimal_same(&test_data_1, &test_data_2),
+        "test_data_1 != test_data_2");
+    while (test_len) {
+        test_len--;
+        len = host_n_port_minimal_context_decode(
+            apdu, test_len, tag_number, NULL, NULL);
+        zassert_true(len < 0, "len=%d test_len=%d", len, test_len);
+    }
+}
+
 static void test_HostNPortMinimal_Copy(BACNET_HOST_N_PORT *data)
 {
     BACNET_HOST_N_PORT_MINIMAL test_data_1 = { 0 }, test_data_2 = { 0 };
@@ -364,6 +430,7 @@ void test_main(void)
     ztest_test_suite(
         host_n_port_tests, ztest_unit_test(test_HostNPort),
         ztest_unit_test(test_HostNPortMinimal_Codec),
+        ztest_unit_test(test_HostNPortMinimalContext_Codec),
         ztest_unit_test(test_is_valid_hostname),
         ztest_unit_test(test_fdt_entry));