Implement socks5 support

This adds following settings:

- Socks5Enabled
- Socks5Host
- Socks5Port
- Socks5User
- Socks5Password

Currently http requests and dns requests are not getting executed as they currently can't get tunneled through socks5 proxy. Therefore gmail with oauth2 wont work through tor.

src/imap.rs

@@ -27,6 +27,7 @@ use crate::events::EventType;
 use crate::headerdef::{HeaderDef, HeaderDefMap};
 use crate::job::{self, Action};
 use crate::login_param::{CertificateChecks, LoginParam, ServerLoginParam};
+use crate::login_param::{ServerAddress, Socks5Config};
 use crate::message::{self, update_server_uid, MessageState};
 use crate::mimeparser;
 use crate::oauth2::dc_get_oauth2_access_token;
@@ -142,6 +143,7 @@ impl FolderMeaning {
 struct ImapConfig {
     pub addr: String,
     pub lp: ServerLoginParam,
+    pub socks5_config: Option<Socks5Config>,
     pub strict_tls: bool,
     pub oauth2: bool,
     pub selected_folder: Option<String>,
@@ -165,6 +167,7 @@ impl Imap {
     /// `addr` is used to renew token if OAuth2 authentication is used.
     pub async fn new(
         lp: &ServerLoginParam,
+        socks5_config: Option<Socks5Config>,
         addr: &str,
         oauth2: bool,
         provider_strict_tls: bool,
@@ -183,6 +186,7 @@ impl Imap {
         let config = ImapConfig {
             addr: addr.to_string(),
             lp: lp.clone(),
+            socks5_config,
             strict_tls,
             oauth2,
             selected_folder: None,
@@ -222,6 +226,7 @@ impl Imap {
 
         let imap = Self::new(
             &param.imap,
+            param.socks5_config.clone(),
             &param.addr,
             param.server_flags & DC_LP_AUTH_OAUTH2 != 0,
             param.provider.map_or(false, |provider| provider.strict_tls),
@@ -261,7 +266,20 @@ impl Imap {
             let imap_server: &str = config.lp.server.as_ref();
             let imap_port = config.lp.port;
 
-            match Client::connect_insecure((imap_server, imap_port)).await {
+            let connection = if let Some(socks5_config) = &config.socks5_config {
+                Client::connect_insecure_socks5(
+                    &ServerAddress {
+                        host: imap_server.to_string(),
+                        port: imap_port,
+                    },
+                    socks5_config.clone(),
+                )
+                .await
+            } else {
+                Client::connect_insecure((imap_server, imap_port)).await
+            };
+
+            match connection {
                 Ok(client) => {
                     if config.lp.security == Socket::Starttls {
                         client.secure(imap_server, config.strict_tls).await
@@ -276,7 +294,20 @@ impl Imap {
             let imap_server: &str = config.lp.server.as_ref();
             let imap_port = config.lp.port;
 
-            Client::connect_secure((imap_server, imap_port), imap_server, config.strict_tls).await
+            if let Some(socks5_config) = &config.socks5_config {
+                Client::connect_secure_socks5(
+                    &ServerAddress {
+                        host: imap_server.to_string(),
+                        port: imap_port,
+                    },
+                    config.strict_tls,
+                    socks5_config.clone(),
+                )
+                .await
+            } else {
+                Client::connect_secure((imap_server, imap_port), imap_server, config.strict_tls)
+                    .await
+            }
         };
 
         let login_res = match connection_res {