removing entropy part as it didn't add anything

emailflow.md

@@ -3,21 +3,28 @@
 In creating an email flow that maintains PRIVACY and SECURITY whilst also being convenient to use, the following principles were observed:
 
 - Keypair must be generated client-side
-- Keypair must be protected by a password
-- There must be protection from keyloggers
+- Keypair must be protected by a long and complex password
 - It must be possible to change the password
 - It must remain possible to work offline
 - Network traffic must not contain identifying metadata
 
-All of the above is achieved using a high level flow as follows:
+All of the above is achieved using a high level signup flow as follows:
 
-1. Generate temporary key pair for secure server communication
-2. Validate email using a 6 digit code
-3. Provide some server side entropy to client
-4. Combine entropy + complex user password to encrypt the final keypair
-5. Store the encrypted keypair on the server
+1. User provides email and complex password
+2. These are used to encrypt a locally generated keypair into a backup
+3. Email address, Public Key and encrypted backup are sent to the server
+4. Account is validated
 
-The password is only used to encrypt the key and is never stored or sent anywhere.  Hence, the server cannot decrypt the backup.  All key signing / encryption operations happen on client side using [private class properties](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Classes/Private_properties).
+The password is only used to encrypt/decrypt the local backup and is never stored or sent anywhere.  
+
+When perforing a login, the flow is:
+
+1. Generate a temporary key pair for secure server communication
+2. Validate the email
+3. Provide the encrypted keypair for the user to unlock
+
+
+All key signing / encryption operations happen on client side using [private class properties](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Classes/Private_properties).
 
 ## SIGNUP FLOW
 
@@ -27,47 +34,44 @@ sequenceDiagram
     autoNumber
     actor U as SIGit User
     participant W as SIGit Website
-    participant D as DVM
-    Participant DB as DataBase
-    Note over W,D: All comms over <br> Nostr Relay
-    U->>W: Click SIGNUP and enter <br>email address
-    Note over W: Ephemeral key generated <br> to communicate with DVM
-    W->>D: Request Account
-    Note right of W: Event uses PoW and<br> encrypts only EMAIL<br> to dvm@sigit.io pubkey
-    D -x DB: Verify PoW and check<br> if email exists
-    Note over D: If email already exists, <br>send user to LOGIN.<br> Otherwise#58;
-    D->>DB: Create Temp Session
-    Note over DB: SESSION entry#58;<br>#128274;session.pubkey="ephemeral pubkey"<br>session.email=lowcase($EMAIL)<br>session.email_code=INT (6 digits)<br>session.created_at=now()
+    participant D as Server
+    Participant DB 
+    Note over W,D: All comms encrypted with throwaway <br>(ephemeral) client keys and a <br>.well-known server key
+    U->>W: Click SIGNUP 
+    U->>W: Provide Email and Complex Password
+    Note over W: Validate Email<br>Ensure Complex Password
+
+    Note right of U: User is warned that they CANNOT<br>RESET PASSWORD, should USE <br>PASSWORD MANAGER etc
+
+    
+    Note over W: Nostr Keypair Generated <br> & Encrypted inside a <br> PRIVATE method,<br>with COMPLEX password.<br> Password variable is not <br>stored, sent or printed <br> anywhere. <br>Any sensitive variables <br>are immediately destroyed.
+    W->>D: Request account activation 
+    Note right of W: Event uses PoW and<br> encrypts PUBKEY, EMAIL,<br> and the encrypted BACKUP<br> to the dvm@sigit.io pubkey<br> using the ephemeral key
+    Note over D: Verify PoW, <br>event.created_at,<br>event.id
+    D -x DB: Check if email exists
+    Note over D: If email already exists, and <br>user.last_seen <> null then <br>send user to LOGIN.<br><br>If email exists and last_seen<br> is null, then DELETE the <br>current entry.<br><br> Otherwise#58;
+    D->>DB: Create DB entries
+    Note over DB: USER insert#58;<br>#128274;user.id=uid()<br>user.pubkey=lowcase($PUBKEY)<br>user.email=lowcase($EMAIL)<br>user.last_seen=null<br>user.created_at=now()<br>user.bkp=$BACKUP
+    Note over DB: SESSION insert#58;<br>#128274;session.pubkey="ephemeral pubkey"<br>session.email_code=INT (6 digits)<br>session.user_id=user.id<br>session.created_at=now()
     D->>U: Send session.email_code via email
     D->>W: Account created
-    Note left of D: Payload is an empty string or<br> an encrypted (and detailed)<br> error message
+    Note left of D: Payload is the user.id and/or<br> an encrypted (and detailed)<br> error message
+    Note over W: Verify DVM pubkey, <br> event.created_at,<br>event.id
     W->>U: Tell user to check email and<br>to open it in the <br> SAME BROWSER SESSION
     Note over W: Screen to accept the 6 digits <br> is already displayed<br>(mobile optimised if relevant)
     U->>W: User opens link or enters the code
     W->>D: Verify Account
-    Note right of W: Event uses PoW and <br>encrypts only CODE<br> to DVM pubkey
+    Note right of W: Event uses PoW and <br>encrypts both user_id <br>and email_code<br> to DVM pubkey
     D -x DB: Check email_code where <br>session pk=event pk
-    D->>DB: If code matches,<br>create User Account
-    Note over DB: USER entry#58;<br>#128274;user.id=uid()<br>user.email=session.email<br>user.pubkey=""<br>user.activated=false<br>user.created_at=now()<br>user.bkp=""<br>user.entropy=uid()
-    D->>W: Provide user.entropy
-    Note left of D: Payload encrypted to ephemeral <br>pubkey. Is either a UID or a <br> detailed error message.
-    Note over W: Client verifies that <br> DVM response came from <br> DVM pubkey
-    W->>U: Ask for secure password
-    Note right of U: This password is what prevents<br>backend from decrypting the nsec
-    Note right of U: User is warned that they CANNOT<br>RESET PASSWORD, should USE <br>PASSWORD MANAGER etc
-    U->>W: Enter password (twice)
+    D->>DB: If email_code matches, <br>update USER table where<br> session.user_id=user.id
 
-    Note over W: Nostr Keypair Generated <br> & Encrypted inside a <br> PRIVATE METHOD,<br>using password + entropy.<br> Password variable is not <br>stored, sent or printed <br> anywhere. Temporary <br>variables are destroyed.
 
-    W->>D: Request account activation
-    Note right of W: Event uses PoW and<br> encrypts both PUBKEY<br> and the already-<br>encrypted BACKUP<br> to the DVM pubkey
-    D -x DB: Ensure event pubkey <br> in SESSION table
-    D->>DB: Update Account
-    Note over DB: user.activated=true <br>user.pubkey=$pubkey<br>user.bkp=$backup
+    Note over DB: USER update#58;<br>user.last_seen=now()
     D->>W: Account activated
     Note left of D: Payload is an empty string or<br> an encrypted (and detailed)<br> error message
+    Note over W: Verify DVM pubkey, <br> event.created_at,<br>event.id
     W->>U: User is automatically logged in
-    Note over W: Ephemeral key is destroyed<br>Default relay list applied
+    Note over W: Ephemeral key is destroyed<br>Default relay list is broadcast<br> using the user pubkey
 ```