refactor: Don't even parse Autocrypt header for outgoing messages (#5259)

Accordingly, there's no need in `Peerstate` for self addresses (and in the db too).

src/decrypt.rs

@@ -12,7 +12,7 @@ use crate::authres::{self, DkimResults};
 use crate::contact::addr_cmp;
 use crate::context::Context;
 use crate::headerdef::{HeaderDef, HeaderDefMap};
-use crate::key::{self, DcKey, Fingerprint, SignedPublicKey, SignedSecretKey};
+use crate::key::{DcKey, Fingerprint, SignedPublicKey, SignedSecretKey};
 use crate::peerstate::Peerstate;
 use crate::pgp;
 
@@ -69,25 +69,26 @@ pub(crate) async fn prepare_decryption(
         });
     }
 
-    let autocrypt_header =
-        if let Some(autocrypt_header_value) = mail.headers.get_header_value(HeaderDef::Autocrypt) {
-            match Aheader::from_str(&autocrypt_header_value) {
-                Ok(header) if addr_cmp(&header.addr, from) => Some(header),
-                Ok(header) => {
-                    warn!(
-                        context,
-                        "Autocrypt header address {:?} is not {:?}.", header.addr, from
-                    );
-                    None
-                }
-                Err(err) => {
-                    warn!(context, "Failed to parse Autocrypt header: {:#}.", err);
-                    None
-                }
+    let autocrypt_header = if context.is_self_addr(from).await? {
+        None
+    } else if let Some(aheader_value) = mail.headers.get_header_value(HeaderDef::Autocrypt) {
+        match Aheader::from_str(&aheader_value) {
+            Ok(header) if addr_cmp(&header.addr, from) => Some(header),
+            Ok(header) => {
+                warn!(
+                    context,
+                    "Autocrypt header address {:?} is not {:?}.", header.addr, from
+                );
+                None
             }
-        } else {
-            None
-        };
+            Err(err) => {
+                warn!(context, "Failed to parse Autocrypt header: {:#}.", err);
+                None
+            }
+        }
+    } else {
+        None
+    };
 
     let dkim_results = handle_authres(context, mail, from, message_time).await?;
 
@@ -265,21 +266,16 @@ pub(crate) fn validate_detached_signature<'a, 'b>(
 }
 
 /// Returns public keyring for `peerstate`.
-pub(crate) async fn keyring_from_peerstate(
-    context: &Context,
-    peerstate: Option<&Peerstate>,
-) -> Result<Vec<SignedPublicKey>> {
+pub(crate) fn keyring_from_peerstate(peerstate: Option<&Peerstate>) -> Vec<SignedPublicKey> {
     let mut public_keyring_for_validate = Vec::new();
     if let Some(peerstate) = peerstate {
         if let Some(key) = &peerstate.public_key {
             public_keyring_for_validate.push(key.clone());
         } else if let Some(key) = &peerstate.gossip_key {
             public_keyring_for_validate.push(key.clone());
-        } else if context.is_self_addr(&peerstate.addr).await? {
-            public_keyring_for_validate = key::load_self_public_keyring(context).await?;
         }
     }
-    Ok(public_keyring_for_validate)
+    public_keyring_for_validate
 }
 
 /// Applies Autocrypt header to Autocrypt peer state and saves it into the database.

src/mimeparser.rs

@@ -27,7 +27,7 @@ use crate::decrypt::{
 use crate::dehtml::dehtml;
 use crate::events::EventType;
 use crate::headerdef::{HeaderDef, HeaderDefMap};
-use crate::key::{load_self_secret_keyring, DcKey, Fingerprint, SignedPublicKey};
+use crate::key::{self, load_self_secret_keyring, DcKey, Fingerprint, SignedPublicKey};
 use crate::message::{
     self, set_msg_failed, update_msg_state, Message, MessageState, MsgId, Viewtype,
 };
@@ -304,8 +304,11 @@ impl MimeMessage {
         hop_info += "\n\n";
         hop_info += &decryption_info.dkim_results.to_string();
 
-        let public_keyring =
-            keyring_from_peerstate(context, decryption_info.peerstate.as_ref()).await?;
+        let incoming = !context.is_self_addr(&from.addr).await?;
+        let public_keyring = match decryption_info.peerstate.is_none() && !incoming {
+            true => key::load_self_public_keyring(context).await?,
+            false => keyring_from_peerstate(decryption_info.peerstate.as_ref()),
+        };
         let (mail, mut signatures, encrypted) = match tokio::task::block_in_place(|| {
             try_decrypt(&mail, &private_keyring, &public_keyring)
         }) {
@@ -430,7 +433,6 @@ impl MimeMessage {
             }
         }
 
-        let incoming = !context.is_self_addr(&from.addr).await?;
         let mut parser = MimeMessage {
             parts: Vec::new(),
             headers,

src/peerstate.rs

@@ -16,7 +16,6 @@ use crate::message::Message;
 use crate::mimeparser::SystemMessage;
 use crate::sql::Sql;
 use crate::stock_str;
-use crate::tools;
 
 /// Type of the public key stored inside the peerstate.
 #[derive(Debug)]
@@ -167,7 +166,7 @@ impl Peerstate {
     /// Loads peerstate corresponding to the given address from the database.
     pub async fn from_addr(context: &Context, addr: &str) -> Result<Option<Peerstate>> {
         if context.is_self_addr(addr).await? {
-            return Ok(Some(Peerstate::get_self_stub(addr)));
+            return Ok(None);
         }
         let query = "SELECT addr, last_seen, last_seen_autocrypt, prefer_encrypted, public_key, \
                      gossip_timestamp, gossip_key, public_key_fingerprint, gossip_key_fingerprint, \
@@ -212,7 +211,7 @@ impl Peerstate {
         addr: &str,
     ) -> Result<Option<Peerstate>> {
         if context.is_self_addr(addr).await? {
-            return Ok(Some(Peerstate::get_self_stub(addr)));
+            return Ok(None);
         }
         let query = "SELECT addr, last_seen, last_seen_autocrypt, prefer_encrypted, public_key, \
                      gossip_timestamp, gossip_key, public_key_fingerprint, gossip_key_fingerprint, \
@@ -229,34 +228,6 @@ impl Peerstate {
         Self::from_stmt(context, query, (&fp, &addr, &fp)).await
     }
 
-    /// Returns peerstate stub for self `addr`.
-    ///
-    /// Needed for [`crate::decrypt::keyring_from_peerstate()`] which returns a keyring of all our
-    /// pubkeys for such a stub so that we can check if a message is signed by us.
-    fn get_self_stub(addr: &str) -> Self {
-        let now = tools::time();
-        // We can have multiple pubkeys, just make the corresponding fields None.
-        Self {
-            addr: addr.to_string(),
-            last_seen: now,
-            last_seen_autocrypt: now,
-            prefer_encrypt: EncryptPreference::Mutual,
-            public_key: None,
-            public_key_fingerprint: None,
-            gossip_key: None,
-            gossip_key_fingerprint: None,
-            gossip_timestamp: 0,
-            verified_key: None,
-            verified_key_fingerprint: None,
-            verifier: None,
-            secondary_verified_key: None,
-            secondary_verified_key_fingerprint: None,
-            secondary_verifier: None,
-            backward_verified_key_id: None,
-            fingerprint_changed: false,
-        }
-    }
-
     async fn from_stmt(
         context: &Context,
         query: &str,