Refactored TLV

* Added support for zero-length TLV
* Added SEPARATOR as a formal kTLVType (and updated listControllers() to use)
* Added `uint8_t *buf(tagType tag, uint8_t *src, int len);` to load buffer needing external memcpy (and updated listControllers() to use)

src/HAP.cpp

@@ -106,6 +106,16 @@ void HAPClient::init(){
     nvs_commit(hapNVS);                                                      // commit to NVS
   }
 
+  if(!nvs_get_blob(hapNVS,"CONTROLLERS",NULL,&len)){                // if found long-term Controller Pairings data from NVS
+    TempBuffer <Controller> tBuf(len/sizeof(Controller));
+    nvs_get_blob(hapNVS,"CONTROLLERS",tBuf.get(),&len);             // retrieve data
+    Serial.printf("*** SIZE %d ***\n",tBuf.size());
+    for(int i=0;i<tBuf.size();i++){
+      if(tBuf.get()[i].allocated)
+        controllerList.push_back(tBuf.get()[i]);
+    }
+  }
+  
   LOG0("Accessory ID:      ");
   charPrintRow(accessory.ID,17);
   LOG0("                               LTPK: ");
@@ -114,7 +124,8 @@ void HAPClient::init(){
 
   printControllers();                                                         
 
-  tlv8.create(kTLVType_State,1,"STATE");                 // define the actual TLV records needed for the implementation of HAP; one for each kTLVType needed (HAP Table 5-6)
+  tlv8.create(kTLVType_Separator,0,"SEPARATOR");   // define the actual TLV records needed for the implementation of HAP; one for each kTLVType needed (HAP Table 5-6)
+  tlv8.create(kTLVType_State,1,"STATE");
   tlv8.create(kTLVType_PublicKey,384,"PUBKEY");
   tlv8.create(kTLVType_Method,1,"METHOD");
   tlv8.create(kTLVType_Salt,16,"SALT");
@@ -476,7 +487,7 @@ int HAPClient::postPairSetupURL(){
     
     case pairState_M5:                     // 'Exchange Request'
 
-      if(!tlv8.buf(kTLVType_EncryptedData)){            
+      if(!tlv8.len(kTLVType_EncryptedData)){            
         LOG0("\n*** ERROR: Required 'EncryptedData' TLV record for this step is bad or missing\n\n");
         tlv8.clear();                                         // clear TLV records
         tlv8.val(kTLVType_State,pairState_M6);                // set State=<M6>
@@ -526,7 +537,7 @@ int HAPClient::postPairSetupURL(){
       tlv8.print(2);             // print decrypted TLV data
       LOG2("------- END DECRYPTED TLVS! -------\n");
        
-      if(!tlv8.buf(kTLVType_Identifier) || !tlv8.buf(kTLVType_PublicKey) || !tlv8.buf(kTLVType_Signature)){            
+      if(!tlv8.len(kTLVType_Identifier) || !tlv8.len(kTLVType_PublicKey) || !tlv8.len(kTLVType_Signature)){            
         LOG0("\n*** ERROR: One or more of required 'Identifier,' 'PublicKey,' and 'Signature' TLV records for this step is bad or missing\n\n");
         tlv8.clear();                                         // clear TLV records
         tlv8.val(kTLVType_State,pairState_M6);                // set State=<M6>
@@ -679,7 +690,7 @@ int HAPClient::postPairVerifyURL(){
 
     case pairState_M1:                     // 'Verify Start Request'
 
-      if(!tlv8.buf(kTLVType_PublicKey)){            
+      if(!tlv8.len(kTLVType_PublicKey)){            
         LOG0("\n*** ERROR: Required 'PublicKey' TLV record for this step is bad or missing\n\n");
         tlv8.clear();                                     // clear TLV records
         tlv8.val(kTLVType_State,pairState_M2);            // set State=<M2>
@@ -745,7 +756,7 @@ int HAPClient::postPairVerifyURL(){
    
     case pairState_M3:                     // 'Verify Finish Request'
 
-      if(!tlv8.buf(kTLVType_EncryptedData)){            
+      if(!tlv8.len(kTLVType_EncryptedData)){            
         LOG0("\n*** ERROR: Required 'EncryptedData' TLV record for this step is bad or missing\n\n");
         tlv8.clear();                                         // clear TLV records
         tlv8.val(kTLVType_State,pairState_M4);                // set State=<M4>
@@ -782,7 +793,7 @@ int HAPClient::postPairVerifyURL(){
       tlv8.print(2);             // print decrypted TLV data
       LOG2("------- END DECRYPTED TLVS! -------\n");
 
-      if(!tlv8.buf(kTLVType_Identifier) || !tlv8.buf(kTLVType_Signature)){            
+      if(!tlv8.len(kTLVType_Identifier) || !tlv8.len(kTLVType_Signature)){            
         LOG0("\n*** ERROR: One or more of required 'Identifier,' and 'Signature' TLV records for this step is bad or missing\n\n");
         tlv8.clear();                                         // clear TLV records
         tlv8.val(kTLVType_State,pairState_M4);                // set State=<M4>
@@ -905,7 +916,7 @@ int HAPClient::postPairingsURL(){
     case 3:
       LOG1("Add...\n");
 
-      if(!tlv8.buf(kTLVType_Identifier) || !tlv8.buf(kTLVType_PublicKey) || !tlv8.buf(kTLVType_Permissions)){            
+      if(!tlv8.len(kTLVType_Identifier) || !tlv8.len(kTLVType_PublicKey) || !tlv8.len(kTLVType_Permissions)){            
         LOG0("\n*** ERROR: One or more of required 'Identifier,' 'PublicKey,' and 'Permissions' TLV records for this step is bad or missing\n\n");
         tlv8.clear();                                         // clear TLV records
         tlv8.val(kTLVType_State,pairState_M2);                // set State=<M2>
@@ -944,7 +955,7 @@ int HAPClient::postPairingsURL(){
     case 4:
       LOG1("Remove...\n");
 
-      if(!tlv8.buf(kTLVType_Identifier)){            
+      if(!tlv8.len(kTLVType_Identifier)){            
         LOG0("\n*** ERROR: Required 'Identifier' TLV record for this step is bad or missing\n\n");
         tlv8.clear();                                         // clear TLV records
         tlv8.val(kTLVType_State,pairState_M2);                // set State=<M2>
@@ -1683,21 +1694,13 @@ int HAPClient::listControllers(uint8_t *tlvBuf){
   tlv8.clear();
   tlv8.val(kTLVType_State,pairState_M2);      
 
-  for(int i=0;i<MAX_CONTROLLERS;i++){           // loop over all controller slots
+  for(auto it=controllerList.begin();it!=controllerList.end();it++){
-    if(controllers[i].allocated){
+    if((*it).allocated){          
-      
+      if(tlv8.val(kTLVType_State)==-1)                // if State is not set then this is not the first controller found
-      if(tlv8.val(kTLVType_State)==-1){          // if State is not set then this is not the first controller found
+        tlv8.val(kTLVType_Separator,1);                                        
-        n=tlv8.separate(tlvBuf);                 // add separator
+      tlv8.val(kTLVType_Permissions,(*it).admin);      
-        nBytes+=n;
+      tlv8.buf(kTLVType_Identifier,(*it).ID,36);
-        if(tlvBuf){
+      tlv8.buf(kTLVType_PublicKey,(*it).LTPK,32);
-          tlvBuf+=n;
-          LOG2("SEPARATOR(0)\n");
-        }
-      }
-                                   
-      tlv8.val(kTLVType_Permissions,controllers[i].admin);      
-      memcpy(tlv8.buf(kTLVType_Identifier,36),controllers[i].ID,36);
-      memcpy(tlv8.buf(kTLVType_PublicKey,32),controllers[i].LTPK,32);
       n=tlv8.pack(tlvBuf);
       nBytes+=n;
       if(tlvBuf){
@@ -1717,24 +1720,41 @@ void HAPClient::printControllers(int minLogLevel){
 
   if(homeSpan.logLevel<minLogLevel)
     return;
-    
+
-  int n=0;
+  if(controllerList.empty()){
+    Serial.printf("No Paired Controllers\n");
+    return;    
+  }
   
-  for(int i=0;i<MAX_CONTROLLERS;i++){           // loop over all controller slots
+  for(auto it=controllerList.begin();it!=controllerList.end();it++){
-    if(controllers[i].allocated){
+    Serial.printf("Paired Controller: ");
-      Serial.printf("Paired Controller: ");
+    charPrintRow((*it).ID,36);
-      charPrintRow(controllers[i].ID,36);
+    Serial.printf("%s  LTPK: ",(*it).admin?"   (admin)":" (regular)");
-      Serial.printf("%s  LTPK: ",controllers[i].admin?"   (admin)":" (regular)");
+    hexPrintRow((*it).LTPK,32);
-      hexPrintRow(controllers[i].LTPK,32);
+    Serial.printf("\n");    
-      Serial.printf("\n");
+  }
-      n++;
+}
-    }
+
+//////////////////////////////////////
+
+void HAPClient::saveControllers(){
+
+  if(controllerList.empty()){
+    nvs_erase_key(hapNVS,"CONTROLLERS");
+    return;
   }
 
-  if(n==0)
+  int n=0;
-    Serial.printf("No Paired Controllers\n");
+  TempBuffer <Controller> tBuf(controllerList.size());    // create temporary buffer to hold Controller data
+  
+  for(auto it=controllerList.begin();it!=controllerList.end();it++)   // store Controller data in temporary buffer
+    tBuf.get()[n++]=(*it);
+
+  nvs_set_blob(hapNVS,"CONTROLLERS",tBuf.get(),tBuf.len());      // update data
+  nvs_commit(hapNVS);                                            // commit to NVS  
 }
 
+
 //////////////////////////////////////
 
 Nonce::Nonce(){
@@ -1766,13 +1786,14 @@ void Nonce::inc(){
 
 // instantiate all static HAP Client structures and data
 
-TLV<kTLVType,10> HAPClient::tlv8;
+TLV<kTLVType,11> HAPClient::tlv8;
 nvs_handle HAPClient::hapNVS;
 nvs_handle HAPClient::srpNVS;
 HKDF HAPClient::hkdf;                                   
 pairState HAPClient::pairStatus;                        
 Accessory HAPClient::accessory;                         
-Controller HAPClient::controllers[MAX_CONTROLLERS];    
+Controller HAPClient::controllers[MAX_CONTROLLERS];
+list<Controller> HAPClient::controllerList;
 SRP6A HAPClient::srp;
 int HAPClient::conNum;
  

src/HAP.h

@@ -77,7 +77,7 @@ struct HAPClient {
   static const int MAX_CONTROLLERS=16;                // maximum number of paired controllers (HAP requires at least 16)
   static const int MAX_ACCESSORIES=41;                // maximum number of allowed Acessories (HAP limit=150, but not enough memory in ESP32 to run that many)
   
-  static TLV<kTLVType,10> tlv8;                       // TLV8 structure (HAP Section 14.1) with space for 10 TLV records of type kTLVType (HAP Table 5-6)
+  static TLV<kTLVType,11> tlv8;                       // TLV8 structure (HAP Section 14.1) with space for 11 TLV records of type kTLVType (HAP Table 5-6)
   static nvs_handle hapNVS;                           // handle for non-volatile-storage of HAP data
   static nvs_handle srpNVS;                           // handle for non-volatile-storage of SRP data
   static HKDF hkdf;                                   // generates (and stores) HKDF-SHA-512 32-byte keys derived from an inputKey of arbitrary length, a salt string, and an info string
@@ -85,6 +85,7 @@ struct HAPClient {
   static SRP6A srp;                                   // stores all SRP-6A keys used for Pair-Setup
   static Accessory accessory;                         // Accessory ID and Ed25519 public and secret keys- permanently stored
   static Controller controllers[MAX_CONTROLLERS];     // Paired Controller IDs and ED25519 long-term public keys - permanently stored
+  static list<Controller> controllerList;             // linked-list of Paired Controller IDs and ED25519 long-term public keys - permanently stored
   static int conNum;                                  // connection number - used to keep track of per-connection EV notifications
 
   // individual structures and data defined for each Hap Client connection
@@ -142,6 +143,7 @@ struct HAPClient {
   static void removeController(uint8_t *id);                                           // removes specific Controller.  If no remaining admin Controllers, remove all others (if any) as per HAP requirements.
   static void printControllers(int minLogLevel=0);                                     // prints IDs of all allocated (paired) Controller, subject to specified minimum log level
   static int listControllers(uint8_t *tlvBuf);                                         // creates and prints a multi-TLV list of Controllers (HAP Section 5.12)
+  static void saveControllers();                                                       // saves Controller list in NVS
   static void checkNotifications();                                                    // checks for Event Notifications and reports to controllers as needed (HAP Section 6.8)
   static void checkTimedWrites();                                                      // checks for expired Timed Write PIDs, and clears any found (HAP Section 6.7.2.4)
   static void eventNotify(SpanBuf *pObj, int nObj, int ignoreClient=-1);               // transmits EVENT Notifications for nObj SpanBuf objects, pObj, with optional flag to ignore a specific client

src/HomeSpan.cpp

@@ -554,6 +554,14 @@ void Span::processSerialCommand(const char *c){
 
   switch(c[0]){
 
+    case 'Z': {
+      TempBuffer <uint8_t> tBuf(HAPClient::listControllers(NULL));
+      HAPClient::listControllers(tBuf.get());
+      Serial.printf("SIZE = %d\n",tBuf.len());
+      HAPClient::hexPrintRow(tBuf.get(),tBuf.len());
+      break;
+    }
+    
     case 's': {    
       
       LOG0("\n*** HomeSpan Status ***\n\n");

src/HomeSpan.h

@@ -38,6 +38,7 @@
 #include <unordered_map>
 #include <vector>
 #include <unordered_set>
+#include <list>
 #include <nvs.h>
 #include <ArduinoOTA.h>
 #include <esp_now.h>
@@ -55,6 +56,7 @@
 using std::vector;
 using std::unordered_map;
 using std::unordered_set;
+using std::list;
 
 enum {
   GET_AID=1,

src/TLV.h

@@ -55,11 +55,11 @@ public:
   int val(tagType tag, uint8_t val);        // sets and returns VAL for TLV with matching TAG (or -1 if no match)    
   uint8_t *buf(tagType tag);                // returns VAL Buffer for TLV with matching TAG (or NULL if no match)
   uint8_t *buf(tagType tag, int len);       // set length and returns VAL Buffer for TLV with matching TAG (or NULL if no match or if LEN>MAX)
+  uint8_t *buf(tagType tag, uint8_t *src, int len);       // copies len bytes of src into VAL buffer, and sets length to len, for TLV with matching TAG; returns VAL Buffer on success, or NULL if no match or if LEN>MAX  
   int len(tagType tag);                     // returns LEN for TLV matching TAG (or 0 if TAG is found but LEN not yet set; -1 if no match at all)
   void print(int minLogLevel=0);            // prints all defined TLVs (those with length>0), subject to specified minimum log level
   int unpack(uint8_t *tlvBuf, int nBytes);  // unpacks nBytes of TLV content from single byte buffer into individual TLV records (return 1 on success, 0 if fail) 
   int pack(uint8_t *tlvBuf);                // if tlvBuf!=NULL, packs all defined TLV records (LEN>0) into a single byte buffer, spitting large TLVs into separate 255-byte chunks.  Returns number of bytes (that would be) stored in buffer
-  int separate(uint8_t *tlvBuf);            // if tlvBuf!=NULL, packs a TLV separator into a single byte buffer.  Returns number of bytes (that would be) stored in buffer
   
 }; // TLV
 
@@ -129,8 +129,12 @@ int TLV<tagType, maxTags>::val(tagType tag){
 
   tlv_t *tlv=find(tag);
 
-  if(tlv && tlv->len>0)
+  if(tlv && tlv->len>=0){
-    return(tlv->val[0]);
+    if(tlv->maxLen>0)
+      return(tlv->val[0]);
+    else
+      return(0);
+  }
 
   return(-1);
 }
@@ -144,8 +148,9 @@ int TLV<tagType, maxTags>::val(tagType tag, uint8_t val){
   tlv_t *tlv=find(tag);
   
   if(tlv){
-    tlv->val[0]=val;
+    if(tlv->maxLen>0)
-    tlv->len=1;
+      tlv->val[0]=val;
+    tlv->len=(tlv->maxLen>0);
     cLen+=tlv->len+2;
     return(val);
   }
@@ -188,6 +193,28 @@ uint8_t *TLV<tagType, maxTags>::buf(tagType tag, int len){
   return(NULL);
 }
 
+//////////////////////////////////////
+// TLV buf(tag, src, len)
+
+template<class tagType, int maxTags>
+uint8_t *TLV<tagType, maxTags>::buf(tagType tag, uint8_t *src, int len){
+
+  tlv_t *tlv=find(tag);
+  
+  if(tlv && len<=tlv->maxLen){
+    tlv->len=len;
+    cLen+=tlv->len;
+
+    for(int i=0;i<tlv->len;i+=255)
+      cLen+=2;
+
+    memcpy(tlv->val,src,len);
+    return(tlv->val);
+  }
+  
+  return(NULL);
+}
+
 //////////////////////////////////////
 // TLV print()
 
@@ -199,7 +226,7 @@ void TLV<tagType, maxTags>::print(int minLogLevel){
     
   for(int i=0;i<numTags;i++){
     
-    if(tlv[i].len>0){
+    if(tlv[i].len>=0){
       Serial.printf("%s(%d) ",tlv[i].name,tlv[i].len);
       
       for(int j=0;j<tlv[i].len;j++)
@@ -209,21 +236,7 @@ void TLV<tagType, maxTags>::print(int minLogLevel){
 
     } // len>0
   } // loop over all TLVs
-}
+}    
-
-//////////////////////////////////////
-// TLV separate(tlvBuf)
-
-template<class tagType, int maxTags>
-int TLV<tagType, maxTags>::separate(uint8_t *tlvBuf){
-  
-  if(tlvBuf){              // load separator
-    *tlvBuf++=kTLVType_Separator;
-    *tlvBuf=0;
-  }
-
-  return(2);
-}     
 
 //////////////////////////////////////
 // TLV pack(tlvBuf)
@@ -234,19 +247,23 @@ int TLV<tagType, maxTags>::pack(uint8_t *tlvBuf){
   int n=0;
   int nBytes;
 
-  for(int i=0;i<numTags;i++){    
+  for(int i=0;i<numTags;i++){     
     
-    if((nBytes=tlv[i].len)>0){
+    if((nBytes=tlv[i].len)>=0){
-      for(int j=0;j<tlv[i].len;j+=255,nBytes-=255){
+      int j=0;
+      do{
+        int wBytes=nBytes>255?255:nBytes;
         if(tlvBuf!=NULL){
           *tlvBuf++=tlv[i].tag;
-          *tlvBuf++=nBytes>255?255:nBytes;
+          *tlvBuf++=wBytes;
-          memcpy(tlvBuf,tlv[i].val+j,nBytes>255?255:nBytes);
+          memcpy(tlvBuf,tlv[i].val+j,wBytes);
-          tlvBuf+=nBytes>255?255:nBytes;
+          tlvBuf+=wBytes;
         }
-        n+=(nBytes>255?255:nBytes)+2;      
+        n+=wBytes+2;
-      } // j-loop
+        j+=wBytes;
-    } // len>0
+        nBytes-=wBytes;      
+      } while(nBytes>0);
+    } // len>=0
     
   } // loop over all TLVs
 

src/Utils.h

@@ -48,11 +48,12 @@ class TempBuffer {
   
   bufType *buf;
   int nBytes;
+  int nElements;
 
   public:
   
-  TempBuffer(size_t len){
+  TempBuffer(int _nElements) : nElements(_nElements) {
-    nBytes=len*sizeof(bufType);
+    nBytes=nElements*sizeof(bufType);
     buf=(bufType *)malloc(nBytes);
     if(buf==NULL){
       Serial.print("\n\n*** FATAL ERROR: Requested allocation of ");
@@ -70,6 +71,10 @@ class TempBuffer {
     return(nBytes);
   }
 
+  int size(){
+    return(nElements);
+  }
+
   bufType *get(){
     return(buf);
   }