Merge 3eb8d92028 into 6a392fdb0f

README.md

@@ -306,9 +306,11 @@ general-purpose CPUs and on microcontrollers. The necessary primitives are:
 - X22519 for ECDH key exchanges
 - HKDF for key derivation
 - Modified Fernet for encrypted tokens
-  - AES-128 in CBC mode
-  - HMAC for message authentication
-  - No Fernet version and timestamp fields
+  - Ephemeral keys derived from an ECDH key exchange on Curve25519
+  - AES-128 in CBC mode with PKCS7 padding
+  - HMAC using SHA256 for message authentication
+  - IVs are generated through os.urandom()
+  - No Fernet version and timestamp metadata fields
 - SHA-256
 - SHA-512
 

RNS/Destination.py

@@ -72,7 +72,16 @@ class Destination:
     directions = [IN, OUT]
 
     PR_TAG_WINDOW = 30
-    RATCHET_COUNT = 512
+
+    RATCHET_COUNT    = 512
+    """
+    The default number of generated ratchet keys a destination will retain, if it has ratchets enabled.
+    """
+
+    RATCHET_INTERVAL = 30*60
+    """
+    The minimum interval between rotating ratchet keys, in seconds.
+    """
 
     @staticmethod
     def expand_name(identity, app_name, *aspects):
@@ -142,6 +151,10 @@ class Destination:
         self.proof_strategy = Destination.PROVE_NONE
         self.ratchets = None
         self.ratchets_path = None
+        self.ratchet_interval = Destination.RATCHET_INTERVAL
+        self.retained_ratchets = Destination.RATCHET_COUNT
+        self.latest_ratchet_time = None
+        self.__enforce_ratchets = False
         self.mtu = 0
 
         self.path_responses = {}
@@ -175,36 +188,12 @@ class Destination:
         """
         return "<"+self.name+"/"+self.hexhash+">"
 
-    def enable_ratchets(self, ratchets_path):
-        if ratchets_path != None:
-            if os.path.isfile(ratchets_path):
-                try:
-                    ratchets_file = open(ratchets_path, "rb")
-                    persisted_data = umsgpack.unpackb(ratchets_file.read())
-                    if "signature" in persisted_data and "ratchets" in persisted_data:
-                        if self.identity.validate(persisted_data["signature"], persisted_data["ratchets"]):
-                            self.ratchets = umsgpack.unpackb(persisted_data["ratchets"])
-                            self.ratchets_path = ratchets_path
-                        else:
-                            raise KeyError("Invalid ratchet file signature")
+    def _clean_ratchets(self):
+        if self.ratchets != None:
+            if len (self.ratchets) > self.retained_ratchets:
+                self.ratchets = self.ratchets[:Destination.RATCHET_COUNT]
 
-                except Exception as e:
-                    self.ratchets = None
-                    self.ratchets_path = None
-                    raise OSError("Could not read ratchet file contents for "+str(self)+". The contained exception was: "+str(e), RNS.LOG_ERROR)
-            else:
-                RNS.log("No existing ratchet data found, initialising new ratchet file for "+str(self), RNS.LOG_DEBUG)
-                self.ratchets = []
-                self.ratchets_path = ratchets_path
-                self.persist_ratchets()
-
-            RNS.log("Ratchets enabled on "+str(self), RNS.LOG_DEBUG) # TODO: Remove
-            return True
-
-        else:
-            raise ValueError("No ratchet file path specified for "+str(self))
-
-    def persist_ratchets(self):
+    def _persist_ratchets(self):
         try:
             packed_ratchets = umsgpack.packb(self.ratchets)
             persisted_data = {"signature": self.sign(packed_ratchets), "ratchets": packed_ratchets}
@@ -218,15 +207,20 @@ class Destination:
 
     def rotate_ratchets(self):
         if self.ratchets != None:
-            RNS.log("Rotating ratchets for "+str(self), RNS.LOG_DEBUG) # TODO: Remove
-            new_ratchet = RNS.Identity._generate_ratchet()
-            self.ratchets.insert(0, new_ratchet)
-            if len (self.ratchets) > Destination.RATCHET_COUNT:
-                self.ratchets = self.ratchets[:Destination.RATCHET_COUNT]
-            self.persist_ratchets()
+            now = time.time()
+            if now > self.latest_ratchet_time+self.ratchet_interval:
+                RNS.log("Rotating ratchets for "+str(self), RNS.LOG_DEBUG)
+                new_ratchet = RNS.Identity._generate_ratchet()
+                self.ratchets.insert(0, new_ratchet)
+                self.latest_ratchet_time = now
+                self._clean_ratchets()
+                self._persist_ratchets()
+            return True
         else:
             raise SystemError("Cannot rotate ratchet on "+str(self)+", ratchets are not enabled")
 
+        return False
+
     def announce(self, app_data=None, path_response=False, attached_interface=None, tag=None, send=True):
         """
         Creates an announce packet for this destination and broadcasts it on all
@@ -272,8 +266,8 @@ class Destination:
                 self.rotate_ratchets()
                 ratchet = RNS.Identity._ratchet_public_bytes(self.ratchets[0])
 
-                # TODO: Remove debug output
-                RNS.log(f"Including ratchet {RNS.prettyhexrep(RNS.Identity.truncated_hash(ratchet))} in announce", RNS.LOG_DEBUG)
+                # TODO: Remove at some point
+                RNS.log(f"Including ratchet {RNS.prettyhexrep(RNS.Identity.truncated_hash(ratchet))} in announce", RNS.LOG_EXTREME)
 
             if app_data == None and self.default_app_data != None:
                 if isinstance(self.default_app_data, bytes):
@@ -366,7 +360,6 @@ class Destination:
         else:
             self.proof_strategy = proof_strategy
 
-
     def register_request_handler(self, path, response_generator = None, allow = ALLOW_NONE, allowed_list = None):
         """
         Registers a request handler.
@@ -388,7 +381,6 @@ class Destination:
             request_handler = [path, response_generator, allow, allowed_list]
             self.request_handlers[path_hash] = request_handler
 
-
     def deregister_request_handler(self, path):
         """
         Deregisters a request handler.
@@ -403,8 +395,6 @@ class Destination:
         else:
             return False
 
-        
-
     def receive(self, packet):
         if packet.packet_type == RNS.Packet.LINKREQUEST:
             plaintext = packet.data
@@ -419,13 +409,99 @@ class Destination:
                         except Exception as e:
                             RNS.log("Error while executing receive callback from "+str(self)+". The contained exception was: "+str(e), RNS.LOG_ERROR)
 
-
     def incoming_link_request(self, data, packet):
         if self.accept_link_requests:
             link = RNS.Link.validate_request(self, data, packet)
             if link != None:
                 self.links.append(link)
 
+    def enable_ratchets(self, ratchets_path):
+        """
+        Enables ratchets on the destination. When ratchets are enabled, Reticulum will automatically rotate
+        the keys used to encrypt packets to this destination, and include the latest ratchet key in announces.
+
+        Enabling ratchets on a destination will provide forward secrecy for packets sent to that destination,
+        even when sent outside a ``Link``. The normal Reticulum ``Link`` establishment procedure already performs
+        its own ephemeral key exchange for each link establishment, which means that ratchets are not necessary
+        to provide forward secrecy for links.
+
+        Enabling ratchets will have a small impact on announce size, adding 32 bytes to every sent announce.
+
+        :param ratchets_path: The path to a file to store ratchet data in.
+        :returns: True if the operation succeeded, otherwise False.
+        """
+        if ratchets_path != None:
+            self.latest_ratchet_time = 0
+            if os.path.isfile(ratchets_path):
+                try:
+                    ratchets_file = open(ratchets_path, "rb")
+                    persisted_data = umsgpack.unpackb(ratchets_file.read())
+                    if "signature" in persisted_data and "ratchets" in persisted_data:
+                        if self.identity.validate(persisted_data["signature"], persisted_data["ratchets"]):
+                            self.ratchets = umsgpack.unpackb(persisted_data["ratchets"])
+                            self.ratchets_path = ratchets_path
+                        else:
+                            raise KeyError("Invalid ratchet file signature")
+
+                except Exception as e:
+                    self.ratchets = None
+                    self.ratchets_path = None
+                    raise OSError("Could not read ratchet file contents for "+str(self)+". The contained exception was: "+str(e), RNS.LOG_ERROR)
+            else:
+                RNS.log("No existing ratchet data found, initialising new ratchet file for "+str(self), RNS.LOG_DEBUG)
+                self.ratchets = []
+                self.ratchets_path = ratchets_path
+                self._persist_ratchets()
+
+            # TODO: Remove at some point
+            RNS.log("Ratchets enabled on "+str(self), RNS.LOG_DEBUG)
+            return True
+
+        else:
+            raise ValueError("No ratchet file path specified for "+str(self))
+
+    def enforce_ratchets(self):
+        """
+        When ratchet enforcement is enabled, this destination will never accept packets that use its
+        base Identity key for encryption, but only accept packets encrypted with one of the retained
+        ratchet keys.
+        """
+        if self.ratchets != None:
+            self.__enforce_ratchets = True
+            RNS.log("Ratchets enforced on "+str(self), RNS.LOG_DEBUG)
+            return True
+        else:
+            return False
+
+    def set_retained_ratchets(self, retained_ratchets):
+        """
+        Sets the number of previously generated ratchet keys this destination will retain,
+        and try to use when decrypting incoming packets. Defaults to ``Destination.RATCHET_COUNT``.
+
+        :param retained_ratchets: The number of generated ratchets to retain.
+        :returns: True if the operation succeeded, False if not.
+        """
+        if isinstance(retained_ratchets, int) and retained_ratchets > 0:
+            self.retained_ratchets = retained_ratchets
+            self._clean_ratchets()
+            return True
+        else:
+            return False
+
+    def set_ratchet_interval(self, interval):
+        """
+        Sets the minimum interval in seconds between ratchet key rotation.
+        Defaults to ``Destination.RATCHET_INTERVAL``.
+
+        :param interval: The minimum interval in seconds.
+        :returns: True if the operation succeeded, False if not.
+        """
+        if isinstance(interval, int) and interval > 0:
+            self.ratchet_interval = interval
+            return True
+        else:
+            return False
+
     def create_keys(self):
         """
         For a ``RNS.Destination.GROUP`` type destination, creates a new symmetric key.
@@ -442,7 +518,6 @@ class Destination:
             self.prv_bytes = Fernet.generate_key()
             self.prv = Fernet(self.prv_bytes)
 
-
     def get_private_key(self):
         """
         For a ``RNS.Destination.GROUP`` type destination, returns the symmetric private key.
@@ -456,7 +531,6 @@ class Destination:
         else:
             return self.prv_bytes
 
-
     def load_private_key(self, key):
         """
         For a ``RNS.Destination.GROUP`` type destination, loads a symmetric private key.
@@ -480,7 +554,6 @@ class Destination:
         else:
             raise TypeError("A single destination holds keys through an Identity instance")
 
-
     def encrypt(self, plaintext):
         """
         Encrypts information for ``RNS.Destination.SINGLE`` or ``RNS.Destination.GROUP`` type destination.
@@ -504,8 +577,6 @@ class Destination:
             else:
                 raise ValueError("No private key held by GROUP destination. Did you create or load one?")
 
-
-
     def decrypt(self, ciphertext):
         """
         Decrypts information for ``RNS.Destination.SINGLE`` or ``RNS.Destination.GROUP`` type destination.
@@ -517,7 +588,7 @@ class Destination:
             return ciphertext
 
         if self.type == Destination.SINGLE and self.identity != None:
-            return self.identity.decrypt(ciphertext, ratchets=self.ratchets)
+            return self.identity.decrypt(ciphertext, ratchets=self.ratchets, enforce_ratchets=self.__enforce_ratchets)
 
         if self.type == Destination.GROUP:
             if hasattr(self, "prv") and self.prv != None:
@@ -529,7 +600,6 @@ class Destination:
             else:
                 raise ValueError("No private key held by GROUP destination. Did you create or load one?")
 
-
     def sign(self, message):
         """
         Signs information for ``RNS.Destination.SINGLE`` type destination.

RNS/Identity.py

@@ -26,6 +26,7 @@ import RNS
 import time
 import atexit
 import hashlib
+import threading
 
 from .vendor import umsgpack as umsgpack
 
@@ -49,11 +50,20 @@ class Identity:
 
     KEYSIZE     = 256*2
     """
-    X25519 key size in bits. A complete key is the concatenation of a 256 bit encryption key, and a 256 bit signing key.
+    X.25519 key size in bits. A complete key is the concatenation of a 256 bit encryption key, and a 256 bit signing key.
     """
 
     RATCHETSIZE = 256
+    """
+    X.25519 ratchet key size in bits.
+    """
+
     RATCHET_EXPIRY = 60*60*24*30
+    """
+    The expiry time for received ratchets in seconds, defaults to 30 days. Reticulum will always use the most recently
+    announced ratchet, and remember it for up to ``RATCHET_EXPIRY`` since receiving it, after which it will be discarded.
+    If a newer ratchet is announced in the meantime, it will be replace the already known ratchet.
+    """
 
     # Non-configurable constants
     FERNET_OVERHEAD           = RNS.Cryptography.Fernet.FERNET_OVERHEAD
@@ -72,6 +82,8 @@ class Identity:
     known_destinations = {}
     known_ratchets = {}
 
+    ratchet_persist_lock = threading.Lock()
+
     @staticmethod
     def remember(packet_hash, destination_hash, public_key, app_data = None):
         if len(public_key) != Identity.KEYSIZE//8:
@@ -237,33 +249,64 @@ class Identity:
 
     @staticmethod
     def _remember_ratchet(destination_hash, ratchet):
-        RNS.log(f"Remembering ratchet {RNS.prettyhexrep(Identity.truncated_hash(ratchet))} for {RNS.prettyhexrep(destination_hash)}", RNS.LOG_DEBUG) # TODO: Remove
+        # TODO: Remove at some point
+        RNS.log(f"Remembering ratchet {RNS.prettyhexrep(Identity.truncated_hash(ratchet))} for {RNS.prettyhexrep(destination_hash)}", RNS.LOG_EXTREME)
         try:
             Identity.known_ratchets[destination_hash] = ratchet
-            hexhash = RNS.hexrep(destination_hash, delimit=False)
-            ratchet_data = {"ratchet": ratchet, "received": time.time()}
 
-            ratchetdir = RNS.Reticulum.storagepath+"/ratchets"
+            if not RNS.Transport.owner.is_connected_to_shared_instance:
+                def persist_job():
+                    with Identity.ratchet_persist_lock:
+                        hexhash = RNS.hexrep(destination_hash, delimit=False)
+                        ratchet_data = {"ratchet": ratchet, "received": time.time()}
 
-            if not os.path.isdir(ratchetdir):
-                os.makedirs(ratchetdir)
+                        ratchetdir = RNS.Reticulum.storagepath+"/ratchets"
                         
-            outpath   = f"{ratchetdir}/{hexhash}.out"
-            finalpath = f"{ratchetdir}/{hexhash}"
-            ratchet_file = open(outpath, "wb")
-            ratchet_file.write(umsgpack.packb(ratchet_data))
-            ratchet_file.close()
-            os.rename(outpath, finalpath)
+                        if not os.path.isdir(ratchetdir):
+                            os.makedirs(ratchetdir)
+
+                        outpath   = f"{ratchetdir}/{hexhash}.out"
+                        finalpath = f"{ratchetdir}/{hexhash}"
+                        ratchet_file = open(outpath, "wb")
+                        ratchet_file.write(umsgpack.packb(ratchet_data))
+                        ratchet_file.close()
+                        os.rename(outpath, finalpath)
+
+                
+                threading.Thread(target=persist_job, daemon=True).start()
 
         except Exception as e:
             RNS.log(f"Could not persist ratchet for {RNS.prettyhexrep(destination_hash)} to storage.", RNS.LOG_ERROR)
             RNS.log(f"The contained exception was: {e}")
             RNS.trace_exception(e)
 
+    @staticmethod
+    def _clean_ratchets():
+        RNS.log("Cleaning ratchets...", RNS.LOG_DEBUG)
+        try:
+            now = time.time()
+            ratchetdir = RNS.Reticulum.storagepath+"/ratchets"
+            for filename in os.listdir(ratchetdir):
+                try:
+                    expired = False
+                    with open(f"{ratchetdir}/{filename}", "rb") as rf:
+                        ratchet_data = umsgpack.unpackb(rf.read())
+                        if now > ratchet_data["received"]+Identity.RATCHET_EXPIRY:
+                            expired = True
+
+                    if expired:
+                        os.unlink(f"{ratchetdir}/{filename}")
+
+                except Exception as e:
+                    RNS.log(f"An error occurred while cleaning ratchets, in the processing of {ratchetdir}/{filename}.", RNS.LOG_ERROR)
+                    RNS.log(f"The contained exception was: {e}", RNS.LOG_ERROR)
+
+        except Exception as e:
+            RNS.log(f"An error occurred while cleaning ratchets. The contained exception was: {e}", RNS.LOG_ERROR)
+
     @staticmethod
     def get_ratchet(destination_hash):
         if not destination_hash in Identity.known_ratchets:
-            RNS.log(f"Trying to load ratchet for {RNS.prettyhexrep(destination_hash)} from storage") # TODO: Remove
             ratchetdir = RNS.Reticulum.storagepath+"/ratchets"
             hexhash = RNS.hexrep(destination_hash, delimit=False)
             ratchet_path = f"{ratchetdir}/hexhash"
@@ -284,6 +327,7 @@ class Identity:
         if destination_hash in Identity.known_ratchets:
             return Identity.known_ratchets[destination_hash]
         else:
+            RNS.log(f"Could not load ratchet for {RNS.prettyhexrep(destination_hash)}", RNS.LOG_DEBUG)
             return None
 
     @staticmethod
@@ -572,7 +616,8 @@ class Identity:
             ephemeral_pub_bytes = ephemeral_key.public_key().public_bytes()
 
             if ratchet != None:
-                RNS.log(f"Encrypting with ratchet {RNS.prettyhexrep(RNS.Identity.truncated_hash(ratchet))}", RNS.LOG_DEBUG) # TODO: Remove
+                # TODO: Remove at some point
+                RNS.log(f"Encrypting with ratchet {RNS.prettyhexrep(RNS.Identity.truncated_hash(ratchet))}", RNS.LOG_EXTREME)
                 target_public_key = X25519PublicKey.from_public_bytes(ratchet)
             else:
                 target_public_key = self.pub
@@ -595,7 +640,7 @@ class Identity:
             raise KeyError("Encryption failed because identity does not hold a public key")
 
 
-    def decrypt(self, ciphertext_token, ratchets=None):
+    def decrypt(self, ciphertext_token, ratchets=None, enforce_ratchets=False):
         """
         Decrypts information for the identity.
 
@@ -626,14 +671,17 @@ class Identity:
                                 fernet = Fernet(derived_key)
                                 plaintext = fernet.decrypt(ciphertext)
                                 
-                                # TODO: Remove
-                                RNS.log(f"Decrypted with ratchet {RNS.prettyhexrep(RNS.Identity.truncated_hash(ratchet_prv.public_key().public_bytes()))}", RNS.LOG_DEBUG)
+                                # TODO: Remove at some point
+                                RNS.log(f"Decrypted with ratchet {RNS.prettyhexrep(RNS.Identity.truncated_hash(ratchet_prv.public_key().public_bytes()))}", RNS.LOG_EXTREME)
                                 
                                 break
                             
                             except Exception as e:
                                 pass
-                                # RNS.log("Decryption using this ratchet failed", RNS.LOG_DEBUG) # TODO: Remove
+
+                    if enforce_ratchets and plaintext == None:
+                        RNS.log("Decryption with ratchet enforcement by "+RNS.prettyhexrep(self.hash)+" failed. Dropping packet.", RNS.LOG_DEBUG)
+                        return None
 
                     if plaintext == None:
                         shared_key = self.prv.exchange(peer_pub)

RNS/Reticulum.py

@@ -295,6 +295,7 @@ class Reticulum:
 
     def __start_jobs(self):
         if self.jobs_thread == None:
+            RNS.Identity._clean_ratchets()
             self.jobs_thread = threading.Thread(target=self.__jobs)
             self.jobs_thread.daemon = True
             self.jobs_thread.start()

RNS/Transport.py

@@ -1604,7 +1604,8 @@ class Transport:
                                                 header_type = RNS.Packet.HEADER_2,
                                                 transport_type = Transport.TRANSPORT,
                                                 transport_id = Transport.identity.hash,
-                                                attached_interface = local_interface
+                                                attached_interface = local_interface,
+                                                context_flag = packet.context_flag,
                                             )
                                             
                                             new_announce.hops = packet.hops
@@ -1621,7 +1622,8 @@ class Transport:
                                                 header_type = RNS.Packet.HEADER_2,
                                                 transport_type = Transport.TRANSPORT,
                                                 transport_id = Transport.identity.hash,
-                                                attached_interface = local_interface
+                                                attached_interface = local_interface,
+                                                context_flag = packet.context_flag,
                                             )
 
                                             new_announce.hops = packet.hops
@@ -1652,7 +1654,8 @@ class Transport:
                                     header_type = RNS.Packet.HEADER_2,
                                     transport_type = Transport.TRANSPORT,
                                     transport_id = Transport.identity.hash,
-                                    attached_interface = attached_interface
+                                    attached_interface = attached_interface,
+                                    context_flag = packet.context_flag,
                                 )
 
                                 new_announce.hops = packet.hops

docs/manual/.buildinfo

@@ -1,4 +1,4 @@
 # Sphinx build info version 1
 # This file hashes the configuration used when building these files. When it is not found, a full rebuild will be done.
-config: 4a5b669a6756de77e9b7c6b7dc5d5702
+config: 895ecce87b0f2ca7fbb104a33248dc3e
 tags: 645f666f9bcd5a90fca523b33c5a78b7

docs/manual/_sources/understanding.rst.txt

@@ -134,10 +134,11 @@ be sufficient, even far into the future.
 By default Reticulum encrypts all data using elliptic curve cryptography and AES. Any packet sent to a
 destination is encrypted with a per-packet derived key. Reticulum can also set up an encrypted
 channel to a destination, called a *Link*. Both data sent over Links and single packets offer
-*Initiator Anonymity*, and links additionally offer *Forward Secrecy* by using an Elliptic Curve
-Diffie Hellman key exchange on Curve25519 to derive per-link ephemeral keys. The multi-hop transport,
-coordination, verification and reliability layers are fully autonomous and also based on elliptic
-curve cryptography.
+*Initiator Anonymity*. Links additionally offer *Forward Secrecy* by default, employing an Elliptic Curve
+Diffie Hellman key exchange on Curve25519 to derive per-link ephemeral keys. Asymmetric, link-less
+packet communication can also provide forward secrecy, with automatic key ratcheting, by enabling
+ratchets on a per-destination basis. The multi-hop transport, coordination, verification and reliability
+layers are fully autonomous and also based on elliptic curve cryptography.
 
 Reticulum also offers symmetric key encryption for group-oriented communications, as well as
 unencrypted packets for local broadcast purposes.
@@ -431,7 +432,7 @@ For exchanges of small amounts of information, Reticulum offers the *Packet* API
 
 * | A packet is always created with an associated destination and some payload data. When the packet is sent
     to a *single* destination type, Reticulum will automatically create an ephemeral encryption key, perform
-    an ECDH key exchange with the destination's public key, and encrypt the information.
+    an ECDH key exchange with the destination's public key (or ratchet key, if available), and encrypt the information.
 
 * | It is important to note that this key exchange does not require any network traffic. The sender already
     knows the public key of the destination from an earlier received *announce*, and can thus perform the ECDH
@@ -867,12 +868,14 @@ both on general-purpose CPUs and on microcontrollers. The necessary primitives a
 
 * HKDF for key derivation
 
-* Fernet for encrypted tokens
+* Modified Fernet for encrypted tokens
 
   * AES-128 in CBC mode
 
   * HMAC for message authentication
 
+  * No Version and Timestamp metadata included
+
 * SHA-256
 
 * SHA-512

docs/manual/_sources/whatis.rst.txt

@@ -53,9 +53,9 @@ What does Reticulum Offer?
 
 * Forward Secrecy by using ephemeral Elliptic Curve Diffie-Hellman keys on Curve25519
 
-* Reticulum uses the `Fernet <https://github.com/fernet/spec/blob/master/Spec.md>`_ specification for on-the-wire / over-the-air encryption
+* Reticulum uses a modified version of the `Fernet <https://github.com/fernet/spec/blob/master/Spec.md>`_ specification for on-the-wire / over-the-air encryption
 
-  * All keys are ephemeral and derived from an ECDH key exchange on Curve25519
+  * Keys are ephemeral and derived from an ECDH key exchange on Curve25519
 
   * AES-128 in CBC mode with PKCS7 padding
 
@@ -63,6 +63,8 @@ What does Reticulum Offer?
 
   * IVs are generated through os.urandom()
 
+  * No Version and Timestamp metadata included
+
 * Unforgeable packet delivery confirmations
 
 * A variety of supported interface types
@@ -99,7 +101,8 @@ of the types of interfaces Reticulum was designed for.
 An open-source LoRa-based interface called `RNode <https://unsigned.io/rnode>`_
 has been designed as an example transceiver that is very suitable for
 Reticulum. It is possible to build it yourself, to transform a common LoRa
-development board into one, or it can be purchased as a complete transceiver.
+development board into one, or it can be purchased as a complete transceiver
+from various vendors.
 
 Reticulum can also be encapsulated over existing IP networks, so there's
 nothing stopping you from using it over wired Ethernet or your local WiFi

docs/manual/_static/documentation_options.js

@@ -1,6 +1,6 @@
 var DOCUMENTATION_OPTIONS = {
     URL_ROOT: document.getElementById("documentation_options").getAttribute('data-url_root'),
-    VERSION: '0.7.6 beta',
+    VERSION: '0.7.7 beta',
     LANGUAGE: 'en',
     COLLAPSE_INDEX: false,
     BUILDER: 'html',

docs/manual/examples.html

@@ -6,7 +6,7 @@
 <link rel="index" title="Index" href="genindex.html" /><link rel="search" title="Search" href="search.html" /><link rel="next" title="Support Reticulum" href="support.html" /><link rel="prev" title="Building Networks" href="networks.html" />
 
     <meta name="generator" content="sphinx-5.3.0, furo 2022.09.29.dev1"/>
-        <title>Code Examples - Reticulum Network Stack 0.7.6 beta documentation</title>
+        <title>Code Examples - Reticulum Network Stack 0.7.7 beta documentation</title>
       <link rel="stylesheet" type="text/css" href="_static/pygments.css" />
     <link rel="stylesheet" type="text/css" href="_static/styles/furo.css?digest=189ec851f9bb375a2509b67be1f64f0cf212b702" />
     <link rel="stylesheet" type="text/css" href="_static/copybutton.css" />
@@ -141,7 +141,7 @@
       </label>
     </div>
     <div class="header-center">
-      <a href="index.html"><div class="brand">Reticulum Network Stack 0.7.6 beta documentation</div></a>
+      <a href="index.html"><div class="brand">Reticulum Network Stack 0.7.7 beta documentation</div></a>
     </div>
     <div class="header-right">
       <div class="theme-toggle-container theme-toggle-header">
@@ -167,7 +167,7 @@
     <img class="sidebar-logo" src="_static/rns_logo_512.png" alt="Logo"/>
   </div>
   
-  <span class="sidebar-brand-text">Reticulum Network Stack 0.7.6 beta documentation</span>
+  <span class="sidebar-brand-text">Reticulum Network Stack 0.7.7 beta documentation</span>
   
 </a><form class="sidebar-search-container" method="get" action="search.html" role="search">
   <input class="sidebar-search" placeholder="Search" name="q" aria-label="Search">

docs/manual/forhumans.html

@@ -6,7 +6,7 @@
 <link rel="index" title="Index" href="genindex.html" /><link rel="search" title="Search" href="search.html" />
 
     <meta name="generator" content="sphinx-5.3.0, furo 2022.09.29.dev1"/>
-        <title>An Explanation of Reticulum for Human Beings - Reticulum Network Stack 0.7.6 beta documentation</title>
+        <title>An Explanation of Reticulum for Human Beings - Reticulum Network Stack 0.7.7 beta documentation</title>
       <link rel="stylesheet" type="text/css" href="_static/pygments.css" />
     <link rel="stylesheet" type="text/css" href="_static/styles/furo.css?digest=189ec851f9bb375a2509b67be1f64f0cf212b702" />
     <link rel="stylesheet" type="text/css" href="_static/copybutton.css" />
@@ -141,7 +141,7 @@
       </label>
     </div>
     <div class="header-center">
-      <a href="index.html"><div class="brand">Reticulum Network Stack 0.7.6 beta documentation</div></a>
+      <a href="index.html"><div class="brand">Reticulum Network Stack 0.7.7 beta documentation</div></a>
     </div>
     <div class="header-right">
       <div class="theme-toggle-container theme-toggle-header">
@@ -167,7 +167,7 @@
     <img class="sidebar-logo" src="_static/rns_logo_512.png" alt="Logo"/>
   </div>
   
-  <span class="sidebar-brand-text">Reticulum Network Stack 0.7.6 beta documentation</span>
+  <span class="sidebar-brand-text">Reticulum Network Stack 0.7.7 beta documentation</span>
   
 </a><form class="sidebar-search-container" method="get" action="search.html" role="search">
   <input class="sidebar-search" placeholder="Search" name="q" aria-label="Search">

docs/manual/genindex.html

@@ -4,7 +4,7 @@
     <meta name="viewport" content="width=device-width,initial-scale=1"/>
     <meta name="color-scheme" content="light dark"><link rel="index" title="Index" href="#" /><link rel="search" title="Search" href="search.html" />
 
-    <meta name="generator" content="sphinx-5.3.0, furo 2022.09.29.dev1"/><title>Index - Reticulum Network Stack 0.7.6 beta documentation</title>
+    <meta name="generator" content="sphinx-5.3.0, furo 2022.09.29.dev1"/><title>Index - Reticulum Network Stack 0.7.7 beta documentation</title>
 <link rel="stylesheet" type="text/css" href="_static/pygments.css" />
     <link rel="stylesheet" type="text/css" href="_static/styles/furo.css?digest=189ec851f9bb375a2509b67be1f64f0cf212b702" />
     <link rel="stylesheet" type="text/css" href="_static/copybutton.css" />
@@ -139,7 +139,7 @@
       </label>
     </div>
     <div class="header-center">
-      <a href="index.html"><div class="brand">Reticulum Network Stack 0.7.6 beta documentation</div></a>
+      <a href="index.html"><div class="brand">Reticulum Network Stack 0.7.7 beta documentation</div></a>
     </div>
     <div class="header-right">
       <div class="theme-toggle-container theme-toggle-header">
@@ -165,7 +165,7 @@
     <img class="sidebar-logo" src="_static/rns_logo_512.png" alt="Logo"/>
   </div>
   
-  <span class="sidebar-brand-text">Reticulum Network Stack 0.7.6 beta documentation</span>
+  <span class="sidebar-brand-text">Reticulum Network Stack 0.7.7 beta documentation</span>
   
 </a><form class="sidebar-search-container" method="get" action="search.html" role="search">
   <input class="sidebar-search" placeholder="Search" name="q" aria-label="Search">
@@ -330,6 +330,8 @@
   <h2>E</h2>
   <table style="width: 100%" class="indextable genindextable"><tr>
     <td style="width: 33%; vertical-align: top;"><ul>
+        <li><a href="reference.html#RNS.Destination.enable_ratchets">enable_ratchets() (RNS.Destination method)</a>
+</li>
         <li><a href="reference.html#RNS.Destination.encrypt">encrypt() (RNS.Destination method)</a>
 
         <ul>
@@ -339,6 +341,8 @@
     </ul></td>
     <td style="width: 33%; vertical-align: top;"><ul>
         <li><a href="reference.html#RNS.Packet.ENCRYPTED_MDU">ENCRYPTED_MDU (RNS.Packet attribute)</a>
+</li>
+        <li><a href="reference.html#RNS.Destination.enforce_ratchets">enforce_ratchets() (RNS.Destination method)</a>
 </li>
         <li><a href="reference.html#RNS.Link.ESTABLISHMENT_TIMEOUT_PER_HOP">ESTABLISHMENT_TIMEOUT_PER_HOP (RNS.Link attribute)</a>
 </li>
@@ -568,6 +572,14 @@
   <h2>R</h2>
   <table style="width: 100%" class="indextable genindextable"><tr>
     <td style="width: 33%; vertical-align: top;"><ul>
+        <li><a href="reference.html#RNS.Destination.RATCHET_COUNT">RATCHET_COUNT (RNS.Destination attribute)</a>
+</li>
+        <li><a href="reference.html#RNS.Identity.RATCHET_EXPIRY">RATCHET_EXPIRY (RNS.Identity attribute)</a>
+</li>
+        <li><a href="reference.html#RNS.Destination.RATCHET_INTERVAL">RATCHET_INTERVAL (RNS.Destination attribute)</a>
+</li>
+        <li><a href="reference.html#RNS.Identity.RATCHETSIZE">RATCHETSIZE (RNS.Identity attribute)</a>
+</li>
         <li><a href="reference.html#RNS.RawChannelReader">RawChannelReader (class in RNS)</a>
 </li>
         <li><a href="reference.html#RNS.RawChannelWriter">RawChannelWriter (class in RNS)</a>
@@ -580,12 +592,12 @@
 </li>
         <li><a href="reference.html#RNS.Channel.Channel.register_message_type">register_message_type() (RNS.Channel.Channel method)</a>
 </li>
+    </ul></td>
+    <td style="width: 33%; vertical-align: top;"><ul>
         <li><a href="reference.html#RNS.Destination.register_request_handler">register_request_handler() (RNS.Destination method)</a>
 </li>
         <li><a href="reference.html#RNS.Reticulum.remote_management_enabled">remote_management_enabled() (RNS.Reticulum static method)</a>
 </li>
-    </ul></td>
-    <td style="width: 33%; vertical-align: top;"><ul>
         <li><a href="reference.html#RNS.Channel.Channel.remove_message_handler">remove_message_handler() (RNS.Channel.Channel method)</a>
 </li>
         <li><a href="reference.html#RNS.RawChannelReader.remove_ready_callback">remove_ready_callback() (RNS.RawChannelReader method)</a>
@@ -633,6 +645,8 @@
         <li><a href="reference.html#RNS.Destination.set_proof_requested_callback">set_proof_requested_callback() (RNS.Destination method)</a>
 </li>
         <li><a href="reference.html#RNS.Destination.set_proof_strategy">set_proof_strategy() (RNS.Destination method)</a>
+</li>
+        <li><a href="reference.html#RNS.Destination.set_ratchet_interval">set_ratchet_interval() (RNS.Destination method)</a>
 </li>
         <li><a href="reference.html#RNS.Link.set_remote_identified_callback">set_remote_identified_callback() (RNS.Link method)</a>
 </li>
@@ -645,6 +659,8 @@
         <li><a href="reference.html#RNS.Link.set_resource_started_callback">set_resource_started_callback() (RNS.Link method)</a>
 </li>
         <li><a href="reference.html#RNS.Link.set_resource_strategy">set_resource_strategy() (RNS.Link method)</a>
+</li>
+        <li><a href="reference.html#RNS.Destination.set_retained_ratchets">set_retained_ratchets() (RNS.Destination method)</a>
 </li>
         <li><a href="reference.html#RNS.PacketReceipt.set_timeout">set_timeout() (RNS.PacketReceipt method)</a>
 </li>

docs/manual/gettingstartedfast.html

@@ -6,7 +6,7 @@
 <link rel="index" title="Index" href="genindex.html" /><link rel="search" title="Search" href="search.html" /><link rel="next" title="Using Reticulum on Your System" href="using.html" /><link rel="prev" title="What is Reticulum?" href="whatis.html" />
 
     <meta name="generator" content="sphinx-5.3.0, furo 2022.09.29.dev1"/>
-        <title>Getting Started Fast - Reticulum Network Stack 0.7.6 beta documentation</title>
+        <title>Getting Started Fast - Reticulum Network Stack 0.7.7 beta documentation</title>
       <link rel="stylesheet" type="text/css" href="_static/pygments.css" />
     <link rel="stylesheet" type="text/css" href="_static/styles/furo.css?digest=189ec851f9bb375a2509b67be1f64f0cf212b702" />
     <link rel="stylesheet" type="text/css" href="_static/copybutton.css" />
@@ -141,7 +141,7 @@
       </label>
     </div>
     <div class="header-center">
-      <a href="index.html"><div class="brand">Reticulum Network Stack 0.7.6 beta documentation</div></a>
+      <a href="index.html"><div class="brand">Reticulum Network Stack 0.7.7 beta documentation</div></a>
     </div>
     <div class="header-right">
       <div class="theme-toggle-container theme-toggle-header">
@@ -167,7 +167,7 @@
     <img class="sidebar-logo" src="_static/rns_logo_512.png" alt="Logo"/>
   </div>
   
-  <span class="sidebar-brand-text">Reticulum Network Stack 0.7.6 beta documentation</span>
+  <span class="sidebar-brand-text">Reticulum Network Stack 0.7.7 beta documentation</span>
   
 </a><form class="sidebar-search-container" method="get" action="search.html" role="search">
   <input class="sidebar-search" placeholder="Search" name="q" aria-label="Search">

docs/manual/hardware.html

@@ -6,7 +6,7 @@
 <link rel="index" title="Index" href="genindex.html" /><link rel="search" title="Search" href="search.html" /><link rel="next" title="Configuring Interfaces" href="interfaces.html" /><link rel="prev" title="Understanding Reticulum" href="understanding.html" />
 
     <meta name="generator" content="sphinx-5.3.0, furo 2022.09.29.dev1"/>
-        <title>Communications Hardware - Reticulum Network Stack 0.7.6 beta documentation</title>
+        <title>Communications Hardware - Reticulum Network Stack 0.7.7 beta documentation</title>
       <link rel="stylesheet" type="text/css" href="_static/pygments.css" />
     <link rel="stylesheet" type="text/css" href="_static/styles/furo.css?digest=189ec851f9bb375a2509b67be1f64f0cf212b702" />
     <link rel="stylesheet" type="text/css" href="_static/copybutton.css" />
@@ -141,7 +141,7 @@
       </label>
     </div>
     <div class="header-center">
-      <a href="index.html"><div class="brand">Reticulum Network Stack 0.7.6 beta documentation</div></a>
+      <a href="index.html"><div class="brand">Reticulum Network Stack 0.7.7 beta documentation</div></a>
     </div>
     <div class="header-right">
       <div class="theme-toggle-container theme-toggle-header">
@@ -167,7 +167,7 @@
     <img class="sidebar-logo" src="_static/rns_logo_512.png" alt="Logo"/>
   </div>
   
-  <span class="sidebar-brand-text">Reticulum Network Stack 0.7.6 beta documentation</span>
+  <span class="sidebar-brand-text">Reticulum Network Stack 0.7.7 beta documentation</span>
   
 </a><form class="sidebar-search-container" method="get" action="search.html" role="search">
   <input class="sidebar-search" placeholder="Search" name="q" aria-label="Search">

docs/manual/index.html

@@ -6,7 +6,7 @@
 <link rel="index" title="Index" href="genindex.html" /><link rel="search" title="Search" href="search.html" /><link rel="next" title="What is Reticulum?" href="whatis.html" />
 
     <meta name="generator" content="sphinx-5.3.0, furo 2022.09.29.dev1"/>
-        <title>Reticulum Network Stack 0.7.6 beta documentation</title>
+        <title>Reticulum Network Stack 0.7.7 beta documentation</title>
       <link rel="stylesheet" type="text/css" href="_static/pygments.css" />
     <link rel="stylesheet" type="text/css" href="_static/styles/furo.css?digest=189ec851f9bb375a2509b67be1f64f0cf212b702" />
     <link rel="stylesheet" type="text/css" href="_static/copybutton.css" />
@@ -141,7 +141,7 @@
       </label>
     </div>
     <div class="header-center">
-      <a href="#"><div class="brand">Reticulum Network Stack 0.7.6 beta documentation</div></a>
+      <a href="#"><div class="brand">Reticulum Network Stack 0.7.7 beta documentation</div></a>
     </div>
     <div class="header-right">
       <div class="theme-toggle-container theme-toggle-header">
@@ -167,7 +167,7 @@
     <img class="sidebar-logo" src="_static/rns_logo_512.png" alt="Logo"/>
   </div>
   
-  <span class="sidebar-brand-text">Reticulum Network Stack 0.7.6 beta documentation</span>
+  <span class="sidebar-brand-text">Reticulum Network Stack 0.7.7 beta documentation</span>
   
 </a><form class="sidebar-search-container" method="get" action="search.html" role="search">
   <input class="sidebar-search" placeholder="Search" name="q" aria-label="Search">

docs/manual/interfaces.html

@@ -6,7 +6,7 @@
 <link rel="index" title="Index" href="genindex.html" /><link rel="search" title="Search" href="search.html" /><link rel="next" title="Building Networks" href="networks.html" /><link rel="prev" title="Communications Hardware" href="hardware.html" />
 
     <meta name="generator" content="sphinx-5.3.0, furo 2022.09.29.dev1"/>
-        <title>Configuring Interfaces - Reticulum Network Stack 0.7.6 beta documentation</title>
+        <title>Configuring Interfaces - Reticulum Network Stack 0.7.7 beta documentation</title>
       <link rel="stylesheet" type="text/css" href="_static/pygments.css" />
     <link rel="stylesheet" type="text/css" href="_static/styles/furo.css?digest=189ec851f9bb375a2509b67be1f64f0cf212b702" />
     <link rel="stylesheet" type="text/css" href="_static/copybutton.css" />
@@ -141,7 +141,7 @@
       </label>
     </div>
     <div class="header-center">
-      <a href="index.html"><div class="brand">Reticulum Network Stack 0.7.6 beta documentation</div></a>
+      <a href="index.html"><div class="brand">Reticulum Network Stack 0.7.7 beta documentation</div></a>
     </div>
     <div class="header-right">
       <div class="theme-toggle-container theme-toggle-header">
@@ -167,7 +167,7 @@
     <img class="sidebar-logo" src="_static/rns_logo_512.png" alt="Logo"/>
   </div>
   
-  <span class="sidebar-brand-text">Reticulum Network Stack 0.7.6 beta documentation</span>
+  <span class="sidebar-brand-text">Reticulum Network Stack 0.7.7 beta documentation</span>
   
 </a><form class="sidebar-search-container" method="get" action="search.html" role="search">
   <input class="sidebar-search" placeholder="Search" name="q" aria-label="Search">

docs/manual/networks.html

@@ -6,7 +6,7 @@
 <link rel="index" title="Index" href="genindex.html" /><link rel="search" title="Search" href="search.html" /><link rel="next" title="Code Examples" href="examples.html" /><link rel="prev" title="Configuring Interfaces" href="interfaces.html" />
 
     <meta name="generator" content="sphinx-5.3.0, furo 2022.09.29.dev1"/>
-        <title>Building Networks - Reticulum Network Stack 0.7.6 beta documentation</title>
+        <title>Building Networks - Reticulum Network Stack 0.7.7 beta documentation</title>
       <link rel="stylesheet" type="text/css" href="_static/pygments.css" />
     <link rel="stylesheet" type="text/css" href="_static/styles/furo.css?digest=189ec851f9bb375a2509b67be1f64f0cf212b702" />
     <link rel="stylesheet" type="text/css" href="_static/copybutton.css" />
@@ -141,7 +141,7 @@
       </label>
     </div>
     <div class="header-center">
-      <a href="index.html"><div class="brand">Reticulum Network Stack 0.7.6 beta documentation</div></a>
+      <a href="index.html"><div class="brand">Reticulum Network Stack 0.7.7 beta documentation</div></a>
     </div>
     <div class="header-right">
       <div class="theme-toggle-container theme-toggle-header">
@@ -167,7 +167,7 @@
     <img class="sidebar-logo" src="_static/rns_logo_512.png" alt="Logo"/>
   </div>
   
-  <span class="sidebar-brand-text">Reticulum Network Stack 0.7.6 beta documentation</span>
+  <span class="sidebar-brand-text">Reticulum Network Stack 0.7.7 beta documentation</span>
   
 </a><form class="sidebar-search-container" method="get" action="search.html" role="search">
   <input class="sidebar-search" placeholder="Search" name="q" aria-label="Search">

docs/manual/reference.html

@@ -6,7 +6,7 @@
 <link rel="index" title="Index" href="genindex.html" /><link rel="search" title="Search" href="search.html" /><link rel="prev" title="Support Reticulum" href="support.html" />
 
     <meta name="generator" content="sphinx-5.3.0, furo 2022.09.29.dev1"/>
-        <title>API Reference - Reticulum Network Stack 0.7.6 beta documentation</title>
+        <title>API Reference - Reticulum Network Stack 0.7.7 beta documentation</title>
       <link rel="stylesheet" type="text/css" href="_static/pygments.css" />
     <link rel="stylesheet" type="text/css" href="_static/styles/furo.css?digest=189ec851f9bb375a2509b67be1f64f0cf212b702" />
     <link rel="stylesheet" type="text/css" href="_static/copybutton.css" />
@@ -141,7 +141,7 @@
       </label>
     </div>
     <div class="header-center">
-      <a href="index.html"><div class="brand">Reticulum Network Stack 0.7.6 beta documentation</div></a>
+      <a href="index.html"><div class="brand">Reticulum Network Stack 0.7.7 beta documentation</div></a>
     </div>
     <div class="header-right">
       <div class="theme-toggle-container theme-toggle-header">
@@ -167,7 +167,7 @@
     <img class="sidebar-logo" src="_static/rns_logo_512.png" alt="Logo"/>
   </div>
   
-  <span class="sidebar-brand-text">Reticulum Network Stack 0.7.6 beta documentation</span>
+  <span class="sidebar-brand-text">Reticulum Network Stack 0.7.7 beta documentation</span>
   
 </a><form class="sidebar-search-container" method="get" action="search.html" role="search">
   <input class="sidebar-search" placeholder="Search" name="q" aria-label="Search">
@@ -356,7 +356,21 @@ for all encrypted communication over Reticulum networks.</p>
 <dl class="py attribute">
 <dt class="sig sig-object py" id="RNS.Identity.KEYSIZE">
 <span class="sig-name descname"><span class="pre">KEYSIZE</span></span><em class="property"><span class="w"> </span><span class="p"><span class="pre">=</span></span><span class="w"> </span><span class="pre">512</span></em><a class="headerlink" href="#RNS.Identity.KEYSIZE" title="Permalink to this definition">#</a></dt>
-<dd><p>X25519 key size in bits. A complete key is the concatenation of a 256 bit encryption key, and a 256 bit signing key.</p>
+<dd><p>X.25519 key size in bits. A complete key is the concatenation of a 256 bit encryption key, and a 256 bit signing key.</p>
+</dd></dl>
+
+<dl class="py attribute">
+<dt class="sig sig-object py" id="RNS.Identity.RATCHETSIZE">
+<span class="sig-name descname"><span class="pre">RATCHETSIZE</span></span><em class="property"><span class="w"> </span><span class="p"><span class="pre">=</span></span><span class="w"> </span><span class="pre">256</span></em><a class="headerlink" href="#RNS.Identity.RATCHETSIZE" title="Permalink to this definition">#</a></dt>
+<dd><p>X.25519 ratchet key size in bits.</p>
+</dd></dl>
+
+<dl class="py attribute">
+<dt class="sig sig-object py" id="RNS.Identity.RATCHET_EXPIRY">
+<span class="sig-name descname"><span class="pre">RATCHET_EXPIRY</span></span><em class="property"><span class="w"> </span><span class="p"><span class="pre">=</span></span><span class="w"> </span><span class="pre">2592000</span></em><a class="headerlink" href="#RNS.Identity.RATCHET_EXPIRY" title="Permalink to this definition">#</a></dt>
+<dd><p>The expiry time for received ratchets in seconds, defaults to 30 days. Reticulum will always use the most recently
+announced ratchet, and remember it for up to <code class="docutils literal notranslate"><span class="pre">RATCHET_EXPIRY</span></code> since receiving it, after which it will be discarded.
+If a newer ratchet is announced in the meantime, it will be replace the already known ratchet.</p>
 </dd></dl>
 
 <dl class="py attribute">
@@ -549,7 +563,7 @@ communication for the identity. Be very careful with this method.</p>
 
 <dl class="py method">
 <dt class="sig sig-object py" id="RNS.Identity.decrypt">
-<span class="sig-name descname"><span class="pre">decrypt</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">ciphertext_token</span></span></em>, <em class="sig-param"><span class="n"><span class="pre">ratchets</span></span><span class="o"><span class="pre">=</span></span><span class="default_value"><span class="pre">None</span></span></em><span class="sig-paren">)</span><a class="headerlink" href="#RNS.Identity.decrypt" title="Permalink to this definition">#</a></dt>
+<span class="sig-name descname"><span class="pre">decrypt</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">ciphertext_token</span></span></em>, <em class="sig-param"><span class="n"><span class="pre">ratchets</span></span><span class="o"><span class="pre">=</span></span><span class="default_value"><span class="pre">None</span></span></em>, <em class="sig-param"><span class="n"><span class="pre">enforce_ratchets</span></span><span class="o"><span class="pre">=</span></span><span class="default_value"><span class="pre">False</span></span></em><span class="sig-paren">)</span><a class="headerlink" href="#RNS.Identity.decrypt" title="Permalink to this definition">#</a></dt>
 <dd><p>Decrypts information for the identity.</p>
 <dl class="field-list simple">
 <dt class="field-odd">Parameters<span class="colon">:</span></dt>
@@ -624,6 +638,18 @@ encrypted communication with it.</p>
 </ul>
 </dd>
 </dl>
+<dl class="py attribute">
+<dt class="sig sig-object py" id="RNS.Destination.RATCHET_COUNT">
+<span class="sig-name descname"><span class="pre">RATCHET_COUNT</span></span><em class="property"><span class="w"> </span><span class="p"><span class="pre">=</span></span><span class="w"> </span><span class="pre">512</span></em><a class="headerlink" href="#RNS.Destination.RATCHET_COUNT" title="Permalink to this definition">#</a></dt>
+<dd><p>The default number of generated ratchet keys a destination will retain, if it has ratchets enabled.</p>
+</dd></dl>
+
+<dl class="py attribute">
+<dt class="sig sig-object py" id="RNS.Destination.RATCHET_INTERVAL">
+<span class="sig-name descname"><span class="pre">RATCHET_INTERVAL</span></span><em class="property"><span class="w"> </span><span class="p"><span class="pre">=</span></span><span class="w"> </span><span class="pre">1800</span></em><a class="headerlink" href="#RNS.Destination.RATCHET_INTERVAL" title="Permalink to this definition">#</a></dt>
+<dd><p>The minimum interval between rotating ratchet keys, in seconds.</p>
+</dd></dl>
+
 <dl class="py method">
 <dt class="sig sig-object py" id="RNS.Destination.expand_name">
 <em class="property"><span class="pre">static</span><span class="w"> </span></em><span class="sig-name descname"><span class="pre">expand_name</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">identity</span></span></em>, <em class="sig-param"><span class="n"><span class="pre">app_name</span></span></em>, <em class="sig-param"><span class="o"><span class="pre">*</span></span><span class="n"><span class="pre">aspects</span></span></em><span class="sig-paren">)</span><a class="headerlink" href="#RNS.Destination.expand_name" title="Permalink to this definition">#</a></dt>
@@ -774,6 +800,64 @@ proofs should be returned for received packets.</p>
 </dl>
 </dd></dl>
 
+<dl class="py method">
+<dt class="sig sig-object py" id="RNS.Destination.enable_ratchets">
+<span class="sig-name descname"><span class="pre">enable_ratchets</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">ratchets_path</span></span></em><span class="sig-paren">)</span><a class="headerlink" href="#RNS.Destination.enable_ratchets" title="Permalink to this definition">#</a></dt>
+<dd><p>Enables ratchets on the destination. When ratchets are enabled, Reticulum will automatically rotate
+the keys used to encrypt packets to this destination, and include the latest ratchet key in announces.</p>
+<p>Enabling ratchets on a destination will provide forward secrecy for packets sent to that destination,
+even when sent outside a <code class="docutils literal notranslate"><span class="pre">Link</span></code>. The normal Reticulum <code class="docutils literal notranslate"><span class="pre">Link</span></code> establishment procedure already performs
+its own ephemeral key exchange for each link establishment, which means that ratchets are not necessary
+to provide forward secrecy for links.</p>
+<p>Enabling ratchets will have a small impact on announce size, adding 32 bytes to every sent announce.</p>
+<dl class="field-list simple">
+<dt class="field-odd">Parameters<span class="colon">:</span></dt>
+<dd class="field-odd"><p><strong>ratchets_path</strong> – The path to a file to store ratchet data in.</p>
+</dd>
+<dt class="field-even">Returns<span class="colon">:</span></dt>
+<dd class="field-even"><p>True if the operation succeeded, otherwise False.</p>
+</dd>
+</dl>
+</dd></dl>
+
+<dl class="py method">
+<dt class="sig sig-object py" id="RNS.Destination.enforce_ratchets">
+<span class="sig-name descname"><span class="pre">enforce_ratchets</span></span><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#RNS.Destination.enforce_ratchets" title="Permalink to this definition">#</a></dt>
+<dd><p>When ratchet enforcement is enabled, this destination will never accept packets that use its
+base Identity key for encryption, but only accept packets encrypted with one of the retained
+ratchet keys.</p>
+</dd></dl>
+
+<dl class="py method">
+<dt class="sig sig-object py" id="RNS.Destination.set_retained_ratchets">
+<span class="sig-name descname"><span class="pre">set_retained_ratchets</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">retained_ratchets</span></span></em><span class="sig-paren">)</span><a class="headerlink" href="#RNS.Destination.set_retained_ratchets" title="Permalink to this definition">#</a></dt>
+<dd><p>Sets the number of previously generated ratchet keys this destination will retain,
+and try to use when decrypting incoming packets. Defaults to <code class="docutils literal notranslate"><span class="pre">Destination.RATCHET_COUNT</span></code>.</p>
+<dl class="field-list simple">
+<dt class="field-odd">Parameters<span class="colon">:</span></dt>
+<dd class="field-odd"><p><strong>retained_ratchets</strong> – The number of generated ratchets to retain.</p>
+</dd>
+<dt class="field-even">Returns<span class="colon">:</span></dt>
+<dd class="field-even"><p>True if the operation succeeded, False if not.</p>
+</dd>
+</dl>
+</dd></dl>
+
+<dl class="py method">
+<dt class="sig sig-object py" id="RNS.Destination.set_ratchet_interval">
+<span class="sig-name descname"><span class="pre">set_ratchet_interval</span></span><span class="sig-paren">(</span><em class="sig-param"><span class="n"><span class="pre">interval</span></span></em><span class="sig-paren">)</span><a class="headerlink" href="#RNS.Destination.set_ratchet_interval" title="Permalink to this definition">#</a></dt>
+<dd><p>Sets the minimum interval in seconds between ratchet key rotation.
+Defaults to <code class="docutils literal notranslate"><span class="pre">Destination.RATCHET_INTERVAL</span></code>.</p>
+<dl class="field-list simple">
+<dt class="field-odd">Parameters<span class="colon">:</span></dt>
+<dd class="field-odd"><p><strong>interval</strong> – The minimum interval in seconds.</p>
+</dd>
+<dt class="field-even">Returns<span class="colon">:</span></dt>
+<dd class="field-even"><p>True if the operation succeeded, False if not.</p>
+</dd>
+</dl>
+</dd></dl>
+
 <dl class="py method">
 <dt class="sig sig-object py" id="RNS.Destination.create_keys">
 <span class="sig-name descname"><span class="pre">create_keys</span></span><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#RNS.Destination.create_keys" title="Permalink to this definition">#</a></dt>
@@ -1964,6 +2048,8 @@ will announce it.</p>
 <li><a class="reference internal" href="#RNS.Identity"><code class="docutils literal notranslate"><span class="pre">Identity</span></code></a><ul>
 <li><a class="reference internal" href="#RNS.Identity.CURVE"><code class="docutils literal notranslate"><span class="pre">CURVE</span></code></a></li>
 <li><a class="reference internal" href="#RNS.Identity.KEYSIZE"><code class="docutils literal notranslate"><span class="pre">KEYSIZE</span></code></a></li>
+<li><a class="reference internal" href="#RNS.Identity.RATCHETSIZE"><code class="docutils literal notranslate"><span class="pre">RATCHETSIZE</span></code></a></li>
+<li><a class="reference internal" href="#RNS.Identity.RATCHET_EXPIRY"><code class="docutils literal notranslate"><span class="pre">RATCHET_EXPIRY</span></code></a></li>
 <li><a class="reference internal" href="#RNS.Identity.TRUNCATED_HASHLENGTH"><code class="docutils literal notranslate"><span class="pre">TRUNCATED_HASHLENGTH</span></code></a></li>
 <li><a class="reference internal" href="#RNS.Identity.recall"><code class="docutils literal notranslate"><span class="pre">recall()</span></code></a></li>
 <li><a class="reference internal" href="#RNS.Identity.recall_app_data"><code class="docutils literal notranslate"><span class="pre">recall_app_data()</span></code></a></li>
@@ -1984,6 +2070,8 @@ will announce it.</p>
 </ul>
 </li>
 <li><a class="reference internal" href="#RNS.Destination"><code class="docutils literal notranslate"><span class="pre">Destination</span></code></a><ul>
+<li><a class="reference internal" href="#RNS.Destination.RATCHET_COUNT"><code class="docutils literal notranslate"><span class="pre">RATCHET_COUNT</span></code></a></li>
+<li><a class="reference internal" href="#RNS.Destination.RATCHET_INTERVAL"><code class="docutils literal notranslate"><span class="pre">RATCHET_INTERVAL</span></code></a></li>
 <li><a class="reference internal" href="#RNS.Destination.expand_name"><code class="docutils literal notranslate"><span class="pre">expand_name()</span></code></a></li>
 <li><a class="reference internal" href="#RNS.Destination.app_and_aspects_from_name"><code class="docutils literal notranslate"><span class="pre">app_and_aspects_from_name()</span></code></a></li>
 <li><a class="reference internal" href="#RNS.Destination.hash_from_name_and_identity"><code class="docutils literal notranslate"><span class="pre">hash_from_name_and_identity()</span></code></a></li>
@@ -1996,6 +2084,10 @@ will announce it.</p>
 <li><a class="reference internal" href="#RNS.Destination.set_proof_strategy"><code class="docutils literal notranslate"><span class="pre">set_proof_strategy()</span></code></a></li>
 <li><a class="reference internal" href="#RNS.Destination.register_request_handler"><code class="docutils literal notranslate"><span class="pre">register_request_handler()</span></code></a></li>
 <li><a class="reference internal" href="#RNS.Destination.deregister_request_handler"><code class="docutils literal notranslate"><span class="pre">deregister_request_handler()</span></code></a></li>
+<li><a class="reference internal" href="#RNS.Destination.enable_ratchets"><code class="docutils literal notranslate"><span class="pre">enable_ratchets()</span></code></a></li>
+<li><a class="reference internal" href="#RNS.Destination.enforce_ratchets"><code class="docutils literal notranslate"><span class="pre">enforce_ratchets()</span></code></a></li>
+<li><a class="reference internal" href="#RNS.Destination.set_retained_ratchets"><code class="docutils literal notranslate"><span class="pre">set_retained_ratchets()</span></code></a></li>
+<li><a class="reference internal" href="#RNS.Destination.set_ratchet_interval"><code class="docutils literal notranslate"><span class="pre">set_ratchet_interval()</span></code></a></li>
 <li><a class="reference internal" href="#RNS.Destination.create_keys"><code class="docutils literal notranslate"><span class="pre">create_keys()</span></code></a></li>
 <li><a class="reference internal" href="#RNS.Destination.get_private_key"><code class="docutils literal notranslate"><span class="pre">get_private_key()</span></code></a></li>
 <li><a class="reference internal" href="#RNS.Destination.load_private_key"><code class="docutils literal notranslate"><span class="pre">load_private_key()</span></code></a></li>

docs/manual/search.html

@@ -4,7 +4,7 @@
     <meta name="viewport" content="width=device-width,initial-scale=1"/>
     <meta name="color-scheme" content="light dark"><link rel="index" title="Index" href="genindex.html" /><link rel="search" title="Search" href="#" />
 
-    <meta name="generator" content="sphinx-5.3.0, furo 2022.09.29.dev1"/><title>Search - Reticulum Network Stack 0.7.6 beta documentation</title><link rel="stylesheet" type="text/css" href="_static/pygments.css" />
+    <meta name="generator" content="sphinx-5.3.0, furo 2022.09.29.dev1"/><title>Search - Reticulum Network Stack 0.7.7 beta documentation</title><link rel="stylesheet" type="text/css" href="_static/pygments.css" />
     <link rel="stylesheet" type="text/css" href="_static/styles/furo.css?digest=189ec851f9bb375a2509b67be1f64f0cf212b702" />
     <link rel="stylesheet" type="text/css" href="_static/copybutton.css" />
     <link rel="stylesheet" type="text/css" href="_static/styles/furo-extensions.css?digest=30d1aed668e5c3a91c3e3bf6a60b675221979f0e" />
@@ -138,7 +138,7 @@
       </label>
     </div>
     <div class="header-center">
-      <a href="index.html"><div class="brand">Reticulum Network Stack 0.7.6 beta documentation</div></a>
+      <a href="index.html"><div class="brand">Reticulum Network Stack 0.7.7 beta documentation</div></a>
     </div>
     <div class="header-right">
       <div class="theme-toggle-container theme-toggle-header">
@@ -164,7 +164,7 @@
     <img class="sidebar-logo" src="_static/rns_logo_512.png" alt="Logo"/>
   </div>
   
-  <span class="sidebar-brand-text">Reticulum Network Stack 0.7.6 beta documentation</span>
+  <span class="sidebar-brand-text">Reticulum Network Stack 0.7.7 beta documentation</span>
   
 </a><form class="sidebar-search-container" method="get" action="#" role="search">
   <input class="sidebar-search" placeholder="Search" name="q" aria-label="Search">

docs/manual/support.html

@@ -6,7 +6,7 @@
 <link rel="index" title="Index" href="genindex.html" /><link rel="search" title="Search" href="search.html" /><link rel="next" title="API Reference" href="reference.html" /><link rel="prev" title="Code Examples" href="examples.html" />
 
     <meta name="generator" content="sphinx-5.3.0, furo 2022.09.29.dev1"/>
-        <title>Support Reticulum - Reticulum Network Stack 0.7.6 beta documentation</title>
+        <title>Support Reticulum - Reticulum Network Stack 0.7.7 beta documentation</title>
       <link rel="stylesheet" type="text/css" href="_static/pygments.css" />
     <link rel="stylesheet" type="text/css" href="_static/styles/furo.css?digest=189ec851f9bb375a2509b67be1f64f0cf212b702" />
     <link rel="stylesheet" type="text/css" href="_static/copybutton.css" />
@@ -141,7 +141,7 @@
       </label>
     </div>
     <div class="header-center">
-      <a href="index.html"><div class="brand">Reticulum Network Stack 0.7.6 beta documentation</div></a>
+      <a href="index.html"><div class="brand">Reticulum Network Stack 0.7.7 beta documentation</div></a>
     </div>
     <div class="header-right">
       <div class="theme-toggle-container theme-toggle-header">
@@ -167,7 +167,7 @@
     <img class="sidebar-logo" src="_static/rns_logo_512.png" alt="Logo"/>
   </div>
   
-  <span class="sidebar-brand-text">Reticulum Network Stack 0.7.6 beta documentation</span>
+  <span class="sidebar-brand-text">Reticulum Network Stack 0.7.7 beta documentation</span>
   
 </a><form class="sidebar-search-container" method="get" action="search.html" role="search">
   <input class="sidebar-search" placeholder="Search" name="q" aria-label="Search">

docs/manual/understanding.html

@@ -6,7 +6,7 @@
 <link rel="index" title="Index" href="genindex.html" /><link rel="search" title="Search" href="search.html" /><link rel="next" title="Communications Hardware" href="hardware.html" /><link rel="prev" title="Using Reticulum on Your System" href="using.html" />
 
     <meta name="generator" content="sphinx-5.3.0, furo 2022.09.29.dev1"/>
-        <title>Understanding Reticulum - Reticulum Network Stack 0.7.6 beta documentation</title>
+        <title>Understanding Reticulum - Reticulum Network Stack 0.7.7 beta documentation</title>
       <link rel="stylesheet" type="text/css" href="_static/pygments.css" />
     <link rel="stylesheet" type="text/css" href="_static/styles/furo.css?digest=189ec851f9bb375a2509b67be1f64f0cf212b702" />
     <link rel="stylesheet" type="text/css" href="_static/copybutton.css" />
@@ -141,7 +141,7 @@
       </label>
     </div>
     <div class="header-center">
-      <a href="index.html"><div class="brand">Reticulum Network Stack 0.7.6 beta documentation</div></a>
+      <a href="index.html"><div class="brand">Reticulum Network Stack 0.7.7 beta documentation</div></a>
     </div>
     <div class="header-right">
       <div class="theme-toggle-container theme-toggle-header">
@@ -167,7 +167,7 @@
     <img class="sidebar-logo" src="_static/rns_logo_512.png" alt="Logo"/>
   </div>
   
-  <span class="sidebar-brand-text">Reticulum Network Stack 0.7.6 beta documentation</span>
+  <span class="sidebar-brand-text">Reticulum Network Stack 0.7.7 beta documentation</span>
   
 </a><form class="sidebar-search-container" method="get" action="search.html" role="search">
   <input class="sidebar-search" placeholder="Search" name="q" aria-label="Search">
@@ -360,10 +360,11 @@ be sufficient, even far into the future.</p>
 <p>By default Reticulum encrypts all data using elliptic curve cryptography and AES. Any packet sent to a
 destination is encrypted with a per-packet derived key. Reticulum can also set up an encrypted
 channel to a destination, called a <em>Link</em>. Both data sent over Links and single packets offer
-<em>Initiator Anonymity</em>, and links additionally offer <em>Forward Secrecy</em> by using an Elliptic Curve
-Diffie Hellman key exchange on Curve25519 to derive per-link ephemeral keys. The multi-hop transport,
-coordination, verification and reliability layers are fully autonomous and also based on elliptic
-curve cryptography.</p>
+<em>Initiator Anonymity</em>. Links additionally offer <em>Forward Secrecy</em> by default, employing an Elliptic Curve
+Diffie Hellman key exchange on Curve25519 to derive per-link ephemeral keys. Asymmetric, link-less
+packet communication can also provide forward secrecy, with automatic key ratcheting, by enabling
+ratchets on a per-destination basis. The multi-hop transport, coordination, verification and reliability
+layers are fully autonomous and also based on elliptic curve cryptography.</p>
 <p>Reticulum also offers symmetric key encryption for group-oriented communications, as well as
 unencrypted packets for local broadcast purposes.</p>
 <p>Reticulum can connect to a variety of interfaces such as radio modems, data radios and serial ports,
@@ -639,7 +640,7 @@ expect. Reticulum offers two ways to do this.</p>
 <li><div class="line-block">
 <div class="line">A packet is always created with an associated destination and some payload data. When the packet is sent
 to a <em>single</em> destination type, Reticulum will automatically create an ephemeral encryption key, perform
-an ECDH key exchange with the destination’s public key, and encrypt the information.</div>
+an ECDH key exchange with the destination’s public key (or ratchet key, if available), and encrypt the information.</div>
 </div>
 </li>
 <li><div class="line-block">
@@ -1068,10 +1069,11 @@ both on general-purpose CPUs and on microcontrollers. The necessary primitives a
 <li><p>Ed25519 for signatures</p></li>
 <li><p>X25519 for ECDH key exchanges</p></li>
 <li><p>HKDF for key derivation</p></li>
-<li><p>Fernet for encrypted tokens</p>
+<li><p>Modified Fernet for encrypted tokens</p>
 <ul>
 <li><p>AES-128 in CBC mode</p></li>
 <li><p>HMAC for message authentication</p></li>
+<li><p>No Version and Timestamp metadata included</p></li>
 </ul>
 </li>
 <li><p>SHA-256</p></li>

docs/manual/using.html

@@ -6,7 +6,7 @@
 <link rel="index" title="Index" href="genindex.html" /><link rel="search" title="Search" href="search.html" /><link rel="next" title="Understanding Reticulum" href="understanding.html" /><link rel="prev" title="Getting Started Fast" href="gettingstartedfast.html" />
 
     <meta name="generator" content="sphinx-5.3.0, furo 2022.09.29.dev1"/>
-        <title>Using Reticulum on Your System - Reticulum Network Stack 0.7.6 beta documentation</title>
+        <title>Using Reticulum on Your System - Reticulum Network Stack 0.7.7 beta documentation</title>
       <link rel="stylesheet" type="text/css" href="_static/pygments.css" />
     <link rel="stylesheet" type="text/css" href="_static/styles/furo.css?digest=189ec851f9bb375a2509b67be1f64f0cf212b702" />
     <link rel="stylesheet" type="text/css" href="_static/copybutton.css" />
@@ -141,7 +141,7 @@
       </label>
     </div>
     <div class="header-center">
-      <a href="index.html"><div class="brand">Reticulum Network Stack 0.7.6 beta documentation</div></a>
+      <a href="index.html"><div class="brand">Reticulum Network Stack 0.7.7 beta documentation</div></a>
     </div>
     <div class="header-right">
       <div class="theme-toggle-container theme-toggle-header">
@@ -167,7 +167,7 @@
     <img class="sidebar-logo" src="_static/rns_logo_512.png" alt="Logo"/>
   </div>
   
-  <span class="sidebar-brand-text">Reticulum Network Stack 0.7.6 beta documentation</span>
+  <span class="sidebar-brand-text">Reticulum Network Stack 0.7.7 beta documentation</span>
   
 </a><form class="sidebar-search-container" method="get" action="search.html" role="search">
   <input class="sidebar-search" placeholder="Search" name="q" aria-label="Search">

docs/manual/whatis.html

@@ -6,7 +6,7 @@
 <link rel="index" title="Index" href="genindex.html" /><link rel="search" title="Search" href="search.html" /><link rel="next" title="Getting Started Fast" href="gettingstartedfast.html" /><link rel="prev" title="Reticulum Network Stack Manual" href="index.html" />
 
     <meta name="generator" content="sphinx-5.3.0, furo 2022.09.29.dev1"/>
-        <title>What is Reticulum? - Reticulum Network Stack 0.7.6 beta documentation</title>
+        <title>What is Reticulum? - Reticulum Network Stack 0.7.7 beta documentation</title>
       <link rel="stylesheet" type="text/css" href="_static/pygments.css" />
     <link rel="stylesheet" type="text/css" href="_static/styles/furo.css?digest=189ec851f9bb375a2509b67be1f64f0cf212b702" />
     <link rel="stylesheet" type="text/css" href="_static/copybutton.css" />
@@ -141,7 +141,7 @@
       </label>
     </div>
     <div class="header-center">
-      <a href="index.html"><div class="brand">Reticulum Network Stack 0.7.6 beta documentation</div></a>
+      <a href="index.html"><div class="brand">Reticulum Network Stack 0.7.7 beta documentation</div></a>
     </div>
     <div class="header-right">
       <div class="theme-toggle-container theme-toggle-header">
@@ -167,7 +167,7 @@
     <img class="sidebar-logo" src="_static/rns_logo_512.png" alt="Logo"/>
   </div>
   
-  <span class="sidebar-brand-text">Reticulum Network Stack 0.7.6 beta documentation</span>
+  <span class="sidebar-brand-text">Reticulum Network Stack 0.7.7 beta documentation</span>
   
 </a><form class="sidebar-search-container" method="get" action="search.html" role="search">
   <input class="sidebar-search" placeholder="Search" name="q" aria-label="Search">
@@ -262,12 +262,13 @@ considered complete and stable at the moment, but could change if absolutely war
 <li><p>Complete initiator anonymity, communicate without revealing your identity</p></li>
 <li><p>Asymmetric encryption based on X25519, and Ed25519 signatures as a basis for all communication</p></li>
 <li><p>Forward Secrecy by using ephemeral Elliptic Curve Diffie-Hellman keys on Curve25519</p></li>
-<li><p>Reticulum uses the <a class="reference external" href="https://github.com/fernet/spec/blob/master/Spec.md">Fernet</a> specification for on-the-wire / over-the-air encryption</p>
+<li><p>Reticulum uses a modified version of the <a class="reference external" href="https://github.com/fernet/spec/blob/master/Spec.md">Fernet</a> specification for on-the-wire / over-the-air encryption</p>
 <ul>
-<li><p>All keys are ephemeral and derived from an ECDH key exchange on Curve25519</p></li>
+<li><p>Keys are ephemeral and derived from an ECDH key exchange on Curve25519</p></li>
 <li><p>AES-128 in CBC mode with PKCS7 padding</p></li>
 <li><p>HMAC using SHA256 for authentication</p></li>
 <li><p>IVs are generated through os.urandom()</p></li>
+<li><p>No Version and Timestamp metadata included</p></li>
 </ul>
 </li>
 <li><p>Unforgeable packet delivery confirmations</p></li>
@@ -300,7 +301,8 @@ of the types of interfaces Reticulum was designed for.</p>
 <p>An open-source LoRa-based interface called <a class="reference external" href="https://unsigned.io/rnode">RNode</a>
 has been designed as an example transceiver that is very suitable for
 Reticulum. It is possible to build it yourself, to transform a common LoRa
-development board into one, or it can be purchased as a complete transceiver.</p>
+development board into one, or it can be purchased as a complete transceiver
+from various vendors.</p>
 <p>Reticulum can also be encapsulated over existing IP networks, so there’s
 nothing stopping you from using it over wired Ethernet or your local WiFi
 network, where it’ll work just as well. In fact, one of the strengths of

docs/source/understanding.rst

@@ -134,10 +134,11 @@ be sufficient, even far into the future.
 By default Reticulum encrypts all data using elliptic curve cryptography and AES. Any packet sent to a
 destination is encrypted with a per-packet derived key. Reticulum can also set up an encrypted
 channel to a destination, called a *Link*. Both data sent over Links and single packets offer
-*Initiator Anonymity*, and links additionally offer *Forward Secrecy* by using an Elliptic Curve
-Diffie Hellman key exchange on Curve25519 to derive per-link ephemeral keys. The multi-hop transport,
-coordination, verification and reliability layers are fully autonomous and also based on elliptic
-curve cryptography.
+*Initiator Anonymity*. Links additionally offer *Forward Secrecy* by default, employing an Elliptic Curve
+Diffie Hellman key exchange on Curve25519 to derive per-link ephemeral keys. Asymmetric, link-less
+packet communication can also provide forward secrecy, with automatic key ratcheting, by enabling
+ratchets on a per-destination basis. The multi-hop transport, coordination, verification and reliability
+layers are fully autonomous and also based on elliptic curve cryptography.
 
 Reticulum also offers symmetric key encryption for group-oriented communications, as well as
 unencrypted packets for local broadcast purposes.
@@ -431,7 +432,7 @@ For exchanges of small amounts of information, Reticulum offers the *Packet* API
 
 * | A packet is always created with an associated destination and some payload data. When the packet is sent
     to a *single* destination type, Reticulum will automatically create an ephemeral encryption key, perform
-    an ECDH key exchange with the destination's public key, and encrypt the information.
+    an ECDH key exchange with the destination's public key (or ratchet key, if available), and encrypt the information.
 
 * | It is important to note that this key exchange does not require any network traffic. The sender already
     knows the public key of the destination from an earlier received *announce*, and can thus perform the ECDH
@@ -867,12 +868,14 @@ both on general-purpose CPUs and on microcontrollers. The necessary primitives a
 
 * HKDF for key derivation
 
-* Fernet for encrypted tokens
+* Modified Fernet for encrypted tokens
 
   * AES-128 in CBC mode
 
   * HMAC for message authentication
 
+  * No Version and Timestamp metadata included
+
 * SHA-256
 
 * SHA-512

docs/source/whatis.rst

@@ -53,9 +53,9 @@ What does Reticulum Offer?
 
 * Forward Secrecy by using ephemeral Elliptic Curve Diffie-Hellman keys on Curve25519
 
-* Reticulum uses the `Fernet <https://github.com/fernet/spec/blob/master/Spec.md>`_ specification for on-the-wire / over-the-air encryption
+* Reticulum uses a modified version of the `Fernet <https://github.com/fernet/spec/blob/master/Spec.md>`_ specification for on-the-wire / over-the-air encryption
 
-  * All keys are ephemeral and derived from an ECDH key exchange on Curve25519
+  * Keys are ephemeral and derived from an ECDH key exchange on Curve25519
 
   * AES-128 in CBC mode with PKCS7 padding
 
@@ -63,6 +63,8 @@ What does Reticulum Offer?
 
   * IVs are generated through os.urandom()
 
+  * No Version and Timestamp metadata included
+
 * Unforgeable packet delivery confirmations
 
 * A variety of supported interface types
@@ -99,7 +101,8 @@ of the types of interfaces Reticulum was designed for.
 An open-source LoRa-based interface called `RNode <https://unsigned.io/rnode>`_
 has been designed as an example transceiver that is very suitable for
 Reticulum. It is possible to build it yourself, to transform a common LoRa
-development board into one, or it can be purchased as a complete transceiver.
+development board into one, or it can be purchased as a complete transceiver
+from various vendors.
 
 Reticulum can also be encapsulated over existing IP networks, so there's
 nothing stopping you from using it over wired Ethernet or your local WiFi