DNS, DKIM and ACME improvements - part 3

crates/common/src/network/autoconfig/autodiscover.rs

@@ -0,0 +1,203 @@
+/*
+ * SPDX-FileCopyrightText: 2020 Stalwart Labs LLC <hello@stalw.art>
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-SEL
+ */
+
+use crate::{Server, manager::application::Resource};
+use quick_xml::Reader;
+use quick_xml::events::Event;
+use registry::schema::enums::ServiceProtocol;
+use std::fmt::Write;
+
+impl Server {
+    pub async fn handle_autodiscover_request(
+        &self,
+        body: Option<Vec<u8>>,
+    ) -> trc::Result<Resource<Vec<u8>>> {
+        // Obtain parameters
+        let emailaddress = parse_autodiscover_request(body.as_deref().unwrap_or_default())
+            .map_err(|err| {
+                trc::ResourceEvent::BadParameters
+                    .into_err()
+                    .details("Failed to parse autodiscover request")
+                    .ctx(trc::Key::Reason, err)
+            })?;
+        let default_host = &self.core.network.server_name;
+
+        // Build XML response
+        let mut config = String::with_capacity(1024);
+        let _ = writeln!(&mut config, "<?xml version=\"1.0\" encoding=\"UTF-8\"?>");
+        let _ = writeln!(
+            &mut config,
+            "<Autodiscover xmlns=\"http://schemas.microsoft.com/exchange/autodiscover/responseschema/2006\">"
+        );
+        let _ = writeln!(
+            &mut config,
+            "\t<Response xmlns=\"http://schemas.microsoft.com/exchange/autodiscover/outlook/responseschema/2006a\">"
+        );
+        let _ = writeln!(&mut config, "\t\t<User>");
+        let _ = writeln!(
+            &mut config,
+            "\t\t\t<DisplayName>{emailaddress}</DisplayName>"
+        );
+        let _ = writeln!(
+            &mut config,
+            "\t\t\t<AutoDiscoverSMTPAddress>{emailaddress}</AutoDiscoverSMTPAddress>"
+        );
+        // DeploymentId is a required field of User but we are not a MS Exchange server so use a random value
+        let _ = writeln!(
+            &mut config,
+            "\t\t\t<DeploymentId>644560b8-a1ce-429c-8ace-23395843f701</DeploymentId>"
+        );
+        let _ = writeln!(&mut config, "\t\t</User>");
+        let _ = writeln!(&mut config, "\t\t<Account>");
+        let _ = writeln!(&mut config, "\t\t\t<AccountType>email</AccountType>");
+        let _ = writeln!(&mut config, "\t\t\t<Action>settings</Action>");
+        for (protocol, service) in &self.core.network.info.services {
+            let (protocol, ports) = match protocol {
+                ServiceProtocol::Imap => ("IMAP", [143, 993]),
+                ServiceProtocol::Pop3 => ("POP3", [110, 995]),
+                ServiceProtocol::Smtp => ("SMTP", [587, 465]),
+                _ => continue,
+            };
+
+            for (is_tls, port) in ports.into_iter().enumerate() {
+                if is_tls == 1 || service.cleartext {
+                    let server_name = service.hostname.as_deref().unwrap_or(default_host);
+                    let _ = writeln!(&mut config, "\t\t\t<Protocol>");
+                    let _ = writeln!(&mut config, "\t\t\t\t<Type>{protocol}</Type>",);
+                    let _ = writeln!(&mut config, "\t\t\t\t<Server>{server_name}</Server>");
+                    let _ = writeln!(&mut config, "\t\t\t\t<Port>{port}</Port>");
+                    let _ = writeln!(&mut config, "\t\t\t\t<LoginName>{emailaddress}</LoginName>");
+                    let _ = writeln!(&mut config, "\t\t\t\t<AuthRequired>on</AuthRequired>");
+                    let _ = writeln!(&mut config, "\t\t\t\t<DirectoryPort>0</DirectoryPort>");
+                    let _ = writeln!(&mut config, "\t\t\t\t<ReferralPort>0</ReferralPort>");
+                    let _ = writeln!(
+                        &mut config,
+                        "\t\t\t\t<SSL>{}</SSL>",
+                        if is_tls == 1 { "on" } else { "off" }
+                    );
+                    if is_tls == 1 {
+                        let _ = writeln!(&mut config, "\t\t\t\t<Encryption>TLS</Encryption>");
+                    }
+                    let _ = writeln!(&mut config, "\t\t\t\t<SPA>off</SPA>");
+                    let _ = writeln!(&mut config, "\t\t\t</Protocol>");
+                }
+            }
+        }
+
+        let _ = writeln!(&mut config, "\t\t</Account>");
+        let _ = writeln!(&mut config, "\t</Response>");
+        let _ = writeln!(&mut config, "</Autodiscover>");
+
+        Ok(Resource::new(
+            "application/xml; charset=utf-8",
+            config.into_bytes(),
+        ))
+    }
+}
+
+fn parse_autodiscover_request(bytes: &[u8]) -> Result<String, String> {
+    if bytes.is_empty() {
+        return Err("Empty request body".to_string());
+    }
+
+    let mut reader = Reader::from_reader(bytes);
+    reader.config_mut().trim_text(true);
+    let mut buf = Vec::with_capacity(128);
+
+    'outer: for tag_name in ["Autodiscover", "Request", "EMailAddress"] {
+        loop {
+            match reader.read_event_into(&mut buf) {
+                Ok(Event::Start(e)) => {
+                    let found_tag_name = e.name();
+                    if tag_name
+                        .as_bytes()
+                        .eq_ignore_ascii_case(found_tag_name.as_ref())
+                    {
+                        continue 'outer;
+                    } else if tag_name == "EMailAddress" {
+                        // Skip unsupported tags under Request, such as AcceptableResponseSchema
+                        let mut tag_count = 0;
+                        loop {
+                            match reader.read_event_into(&mut buf) {
+                                Ok(Event::End(_)) => {
+                                    if tag_count == 0 {
+                                        break;
+                                    } else {
+                                        tag_count -= 1;
+                                    }
+                                }
+                                Ok(Event::Start(_)) => {
+                                    tag_count += 1;
+                                }
+                                Ok(Event::Eof) => {
+                                    return Err(format!(
+                                        "Expected value, found unexpected EOF at position {}.",
+                                        reader.buffer_position()
+                                    ));
+                                }
+                                _ => (),
+                            }
+                        }
+                    } else {
+                        return Err(format!(
+                            "Expected tag {}, found unexpected tag {} at position {}.",
+                            tag_name,
+                            String::from_utf8_lossy(found_tag_name.as_ref()),
+                            reader.buffer_position()
+                        ));
+                    }
+                }
+                Ok(Event::Decl(_) | Event::Text(_)) => (),
+                Err(e) => {
+                    return Err(format!(
+                        "Error at position {}: {:?}",
+                        reader.buffer_position(),
+                        e
+                    ));
+                }
+                Ok(event) => {
+                    return Err(format!(
+                        "Expected tag {}, found unexpected event {event:?} at position {}.",
+                        tag_name,
+                        reader.buffer_position()
+                    ));
+                }
+            }
+        }
+    }
+
+    if let Ok(Event::Text(text)) = reader.read_event_into(&mut buf)
+        && let Ok(text) = text.xml_content()
+        && text.contains('@')
+    {
+        return Ok(text.trim().to_lowercase());
+    }
+
+    Err(format!(
+        "Expected email address, found unexpected value at position {}.",
+        reader.buffer_position()
+    ))
+}
+
+#[cfg(test)]
+mod tests {
+
+    #[test]
+    fn parse_autodiscover() {
+        let r = r#"<?xml version="1.0" encoding="utf-8"?>
+            <Autodiscover xmlns="http://schemas.microsoft.com/exchange/autodiscover/outlook/requestschema/2006">
+                <Request>
+                        <EMailAddress>email@example.com</EMailAddress>
+                        <AcceptableResponseSchema>http://schemas.microsoft.com/exchange/autodiscover/outlook/responseschema/2006a</AcceptableResponseSchema>
+                </Request>
+            </Autodiscover>"#;
+
+        assert_eq!(
+            super::parse_autodiscover_request(r.as_bytes()).unwrap(),
+            "email@example.com"
+        );
+    }
+}

crates/common/src/network/autoconfig/autodiscover_v2.rs

@@ -0,0 +1,57 @@
+/*
+ * SPDX-FileCopyrightText: 2020 Stalwart Labs LLC <hello@stalw.art>
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-SEL
+ */
+
+use crate::{Server, manager::application::Resource};
+use utils::url_params::UrlParams;
+
+impl Server {
+    pub async fn handle_autodiscover_v2_request(
+        &self,
+        query: Option<&str>,
+    ) -> trc::Result<Result<Resource<Vec<u8>>, String>> {
+        // Parse query parameters
+        let params = UrlParams::new(query);
+        let emailaddress = params.get("Email").unwrap_or_default().to_lowercase();
+        let protocol = params.get("Protocol").unwrap_or_default();
+
+        // Validate email address
+        let Some((_, domain)) = emailaddress.rsplit_once('@') else {
+            return Err(trc::ResourceEvent::BadParameters
+                .into_err()
+                .details("Missing domain in email address"));
+        };
+
+        if domain.is_empty() {
+            return Err(trc::ResourceEvent::BadParameters
+                .into_err()
+                .details("Missing domain in email address"));
+        }
+
+        if protocol.eq_ignore_ascii_case("autodiscoverv1") {
+            let server_name = &self.core.network.server_name;
+            let body = format!(
+                "{{\"Protocol\":\"AutodiscoverV1\",\
+                     \"Url\":\"https://{server_name}/autodiscover/autodiscover.xml\"}}"
+            );
+            Ok(Ok(Resource::new(
+                "application/json; charset=utf-8",
+                body.into_bytes(),
+            )))
+        } else {
+            let safe_protocol: String = protocol
+                .chars()
+                .filter(|c| c.is_ascii_alphanumeric())
+                .collect();
+            let err = format!(
+                "{{\"ErrorCode\":\"InvalidProtocol\",\
+                     \"ErrorMessage\":\"The given protocol value \
+                     '{safe_protocol}' is invalid. \
+                     Supported values are 'AutodiscoverV1'\"}}"
+            );
+            Ok(Err(err))
+        }
+    }
+}

crates/common/src/network/autoconfig/legacy_autoconfig.rs

@@ -0,0 +1,104 @@
+/*
+ * SPDX-FileCopyrightText: 2020 Stalwart Labs LLC <hello@stalw.art>
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-SEL
+ */
+
+use crate::{Server, manager::application::Resource};
+use registry::schema::enums::ServiceProtocol;
+use std::fmt::Write;
+use utils::url_params::UrlParams;
+
+impl Server {
+    pub async fn handle_autoconfig_request(
+        &self,
+        uri: Option<&str>,
+    ) -> trc::Result<Resource<Vec<u8>>> {
+        // Obtain parameters
+        let params = UrlParams::new(uri);
+        let emailaddress = params
+            .get("emailaddress")
+            .unwrap_or_default()
+            .to_lowercase();
+        let Some((_, domain)) = emailaddress.rsplit_once('@') else {
+            return Err(trc::ResourceEvent::BadParameters
+                .into_err()
+                .details("Missing domain in email address"));
+        };
+        let default_host = &self.core.network.server_name;
+
+        // Build XML response
+        let mut config = String::with_capacity(1024);
+        config.push_str("<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n");
+        config.push_str("<clientConfig version=\"1.1\">\n");
+        let _ = writeln!(&mut config, "\t<emailProvider id=\"{domain}\">");
+        let _ = writeln!(&mut config, "\t\t<domain>{domain}</domain>");
+        let _ = writeln!(&mut config, "\t\t<displayName>{emailaddress}</displayName>");
+        let _ = writeln!(
+            &mut config,
+            "\t\t<displayShortName>{domain}</displayShortName>"
+        );
+        for (protocol, service) in &self.core.network.info.services {
+            let (protocol, tag, ports) = match protocol {
+                ServiceProtocol::Smtp => ("smtp", "outgoingServer", [587, 465]),
+                ServiceProtocol::Imap => ("imap", "incomingServer", [143, 993]),
+                ServiceProtocol::Pop3 => ("pop3", "incomingServer", [110, 995]),
+                _ => continue,
+            };
+            for (is_tls, port) in ports.into_iter().enumerate() {
+                if is_tls == 1 || service.cleartext {
+                    let server_name = service.hostname.as_deref().unwrap_or(default_host);
+                    let _ = writeln!(&mut config, "\t\t<{tag} type=\"{protocol}\">");
+                    let _ = writeln!(&mut config, "\t\t\t<hostname>{server_name}</hostname>");
+                    let _ = writeln!(&mut config, "\t\t\t<port>{port}</port>");
+                    let _ = writeln!(
+                        &mut config,
+                        "\t\t\t<socketType>{}</socketType>",
+                        if is_tls == 1 { "SSL" } else { "STARTTLS" }
+                    );
+                    let _ = writeln!(&mut config, "\t\t\t<username>{emailaddress}</username>");
+                    let _ = writeln!(
+                        &mut config,
+                        "\t\t\t<authentication>password-cleartext</authentication>"
+                    );
+                    let _ = writeln!(&mut config, "\t\t</{tag}>");
+                }
+            }
+        }
+
+        config.push_str("\t</emailProvider>\n");
+
+        for (protocol, service) in &self.core.network.info.services {
+            let (tag, protocol, url) = match protocol {
+                ServiceProtocol::Carddav => ("addressBook", "carddav", "card"),
+                ServiceProtocol::Caldav => ("calendar", "caldav", "cal"),
+                ServiceProtocol::Webdav => ("fileShare", "webdav", "file"),
+                _ => continue,
+            };
+            let server_name = service.hostname.as_deref().unwrap_or(default_host);
+
+            let _ = writeln!(&mut config, "\t<{tag} type=\"{protocol}\">");
+            let _ = writeln!(&mut config, "\t\t<username>{emailaddress}</username>");
+            let _ = writeln!(
+                &mut config,
+                "\t\t<authentication>http-basic</authentication>"
+            );
+            let _ = writeln!(
+                &mut config,
+                "\t\t<serverURL>https://{server_name}/dav/{url}</serverURL>"
+            );
+            let _ = writeln!(&mut config, "\t</{tag}>");
+        }
+
+        let _ = writeln!(
+            &mut config,
+            "\t<clientConfigUpdate url=\"https://autoconfig.{domain}/mail/config-v1.1.xml\"></clientConfigUpdate>"
+        );
+        config.push_str("</clientConfig>\n");
+
+        Ok(Resource::new(
+            "application/xml; charset=utf-8",
+            config.into_bytes(),
+        ))
+    }
+}

crates/common/src/network/autoconfig/mod.rs

@@ -4,4 +4,7 @@
  * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-SEL
  */
 
+pub mod autodiscover;
+pub mod autodiscover_v2;
+pub mod legacy_autoconfig;
 pub mod pacc;

crates/common/src/network/dkim.rs

@@ -14,6 +14,8 @@ use pkcs8::Document;
 use registry::schema::enums::DkimSignatureType;
 use registry::schema::structs::DkimSignature;
 use rsa::pkcs1::DecodeRsaPublicKey;
+use store::rand::distr::Alphanumeric;
+use store::rand::{self, Rng};
 
 pub async fn generate_dkim_private_key(
     key_type: DkimSignatureType,
@@ -130,11 +132,12 @@ pub fn generate_dkim_dns_record_name(key: &DkimSignature, domain: &str) -> Strin
 /// Generate a DKIM selector from a template string.
 ///
 /// Supported variables:
-/// - `{algorithm}` — signing algorithm in lowercase (`rsa`, `ed25519`)
-/// - `{hash}` — hash algorithm (`sha256`)
-/// - `{version}` — DKIM version number (`1`)
-/// - `{date-<fmt>}` — current UTC date formatted with chrono strftime (e.g. `{date-%Y%m%d}`)
-/// - `{epoch}` — current UTC unix timestamp
+/// - `{algorithm}`: signing algorithm in lowercase (`rsa`, `ed25519`)
+/// - `{hash}`: hash algorithm (`sha256`)
+/// - `{version}`: DKIM version number (`1`)
+/// - `{date-<fmt>}`: current UTC date formatted with chrono strftime (e.g. `{date-%Y%m%d}`)
+/// - `{epoch}`: current UTC unix timestamp
+/// - `{random}`: random 8-character alphanumeric string
 ///
 pub fn generate_dkim_selector(
     template: &str,
@@ -147,7 +150,7 @@ pub fn generate_dkim_selector(
     while !chars.is_empty() {
         // Find next '{' or consume literal text
         let Some(open) = memchr(b'{', chars) else {
-            // No more variables — append remaining literal
+            // No more variables: append remaining literal
             // SAFETY: template is valid UTF-8, and we only slice on ASCII boundaries
             result.extend(
                 chars
@@ -182,6 +185,14 @@ pub fn generate_dkim_selector(
             "epoch" => {
                 result.extend_from_slice(now.timestamp().to_string().as_bytes());
             }
+            "random" => {
+                let rand_str: String = rand::rng()
+                    .sample_iter(Alphanumeric)
+                    .take(8)
+                    .map(|ch| char::from(ch.to_ascii_lowercase()))
+                    .collect::<String>();
+                result.extend(rand_str.as_bytes());
+            }
             v => {
                 if let Some(fmt) = v.strip_prefix("date-") {
                     if fmt.is_empty() {

crates/common/src/network/dns/records.rs

@@ -243,6 +243,15 @@ impl Server {
                                 }),
                             });
                         }
+
+                        // ACME DNS-PERSIST-01 validation record
+                        records.push(NamedDnsRecord {
+                            name: format!("_validation-persist.{domain_name}."),
+                            record: DnsRecord::TXT(format!(
+                                "{provider_name}; accounturi={}",
+                                provider.account_uri
+                            )),
+                        });
                     }
                 }
                 DnsRecordType::Tlsa => {