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

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,