save private key generated during acme handshake

TODO

@@ -0,0 +1,11 @@
+- make acme store implement https://docs.rs/rustls/latest/rustls/server/trait.ResolvesServerCert.html
+
+- pass that into https://docs.rs/rustls/latest/rustls/struct.ConfigBuilder.html#
+
+- turn that into a TlsAcceptor (From is implemented here:
+  https://docs.rs/tokio-rustls/latest/tokio_rustls/struct.TlsAcceptor.html#impl-From%3CArc%3CServerConfig%3E%3E-for-TlsAcceptor)
+
+- use tls-listener crate to wrap hyper accepter: https://github.com/tmccombs/tls-listener/blob/main/examples/http.rs#L24
+    - https://github.com/tmccombs/tls-listener/blob/main/examples/tls_config/mod.rs
+
+- logging

src/domain/acme.rs

@@ -1,5 +1,6 @@
 pub mod manager;
 pub mod store;
 
-pub type AccountKey = openssl::pkey::PKey<openssl::pkey::Private>;
+pub type PrivateKey = openssl::pkey::PKey<openssl::pkey::Private>;
+
 pub type Certificate = openssl::x509::X509;

src/domain/acme/manager.rs

@@ -84,7 +84,7 @@ where
             // if there's an existing cert, and its expiry (determined by the soonest value of
             // not_after amongst its parts) is later than 30 days from now, then we consider it to be
             // synced.
-            if let Ok(cert) = self.store.get_certificate(domain.as_str()) {
+            if let Ok((_, cert)) = self.store.get_certificate(domain.as_str()) {
                 let thirty_days = openssl::asn1::Asn1Time::days_from_now(30)
                     .expect("parsed thirty days from now as Asn1Time");
 
@@ -211,7 +211,7 @@ where
             // Create a certificate signing request for the order, and request
             // the certificate.
             let order = order
-                .finalize(acme2::Csr::Automatic(pkey))
+                .finalize(acme2::Csr::Automatic(pkey.clone()))
                 .await
                 .map_unexpected()?;
 
@@ -260,7 +260,7 @@ where
 
             println!("certificate for {} successfully retrieved", domain.as_str());
             self.store
-                .set_certificate(domain.as_str(), cert)
+                .set_certificate(domain.as_str(), &pkey, cert)
                 .map_unexpected()?;
 
             Ok(())

src/domain/acme/store.rs

@@ -1,11 +1,12 @@
 use std::io::{Read, Write};
 use std::{fs, io, path, sync};
 
-use crate::domain::acme::{AccountKey, Certificate};
+use crate::domain::acme::{Certificate, PrivateKey};
 use crate::error;
 use crate::error::{MapUnexpected, ToUnexpected};
 
 use hex::ToHex;
+use serde::{Deserialize, Serialize};
 use sha2::{Digest, Sha256};
 
 #[derive(thiserror::Error, Debug)]
@@ -37,8 +38,8 @@ pub enum GetCertificateError {
 
 #[mockall::automock]
 pub trait Store {
-    fn set_account_key(&self, k: &AccountKey) -> Result<(), error::Unexpected>;
+    fn set_account_key(&self, k: &PrivateKey) -> Result<(), error::Unexpected>;
-    fn get_account_key(&self) -> Result<AccountKey, GetAccountKeyError>;
+    fn get_account_key(&self) -> Result<PrivateKey, GetAccountKeyError>;
 
     fn set_http01_challenge_key(&self, token: &str, key: &str) -> Result<(), error::Unexpected>;
     fn get_http01_challenge_key(&self, token: &str) -> Result<String, GetHttp01ChallengeKeyError>;
@@ -47,15 +48,25 @@ pub trait Store {
     fn set_certificate(
         &self,
         domain: &str,
+        key: &PrivateKey,
         cert: Vec<Certificate>,
     ) -> Result<(), error::Unexpected>;
 
     /// Returned vec is guaranteed to have len > 0
-    fn get_certificate(&self, domain: &str) -> Result<Vec<Certificate>, GetCertificateError>;
+    fn get_certificate(
+        &self,
+        domain: &str,
+    ) -> Result<(PrivateKey, Vec<Certificate>), GetCertificateError>;
 }
 
 pub trait BoxedStore: Store + Send + Sync + Clone + 'static {}
 
+#[derive(Debug, Serialize, Deserialize)]
+struct StoredPKeyCert {
+    private_key_pem: String,
+    cert_pems: Vec<String>,
+}
+
 struct FSStore {
     dir_path: path::PathBuf,
 }
@@ -86,21 +97,24 @@ impl FSStore {
     }
 
     fn certificate_path(&self, domain: &str) -> path::PathBuf {
-        self.dir_path.join("certificates").join(domain)
+        self.dir_path
+            .join("certificates")
+            .join(domain)
+            .with_extension("json")
     }
 }
 
 impl BoxedStore for sync::Arc<FSStore> {}
 
 impl Store for sync::Arc<FSStore> {
-    fn set_account_key(&self, k: &AccountKey) -> Result<(), error::Unexpected> {
+    fn set_account_key(&self, k: &PrivateKey) -> Result<(), error::Unexpected> {
         let mut file = fs::File::create(self.account_key_path()).map_unexpected()?;
         let pem = k.private_key_to_pem_pkcs8().map_unexpected()?;
         file.write_all(&pem).map_unexpected()?;
         Ok(())
     }
 
-    fn get_account_key(&self) -> Result<AccountKey, GetAccountKeyError> {
+    fn get_account_key(&self) -> Result<PrivateKey, GetAccountKeyError> {
         let mut file = fs::File::open(self.account_key_path()).map_err(|e| match e.kind() {
             io::ErrorKind::NotFound => GetAccountKeyError::NotFound,
             _ => e.to_unexpected().into(),
@@ -109,7 +123,7 @@ impl Store for sync::Arc<FSStore> {
         let mut pem = Vec::<u8>::new();
         file.read_to_end(&mut pem).map_unexpected()?;
 
-        let k = AccountKey::private_key_from_pem(&pem).map_unexpected()?;
+        let k = PrivateKey::private_key_from_pem(&pem).map_unexpected()?;
         Ok(k)
     }
 
@@ -140,38 +154,50 @@ impl Store for sync::Arc<FSStore> {
     fn set_certificate(
         &self,
         domain: &str,
+        key: &PrivateKey,
         cert: Vec<Certificate>,
     ) -> Result<(), error::Unexpected> {
-        let cert: Vec<String> = cert
+        let to_store = StoredPKeyCert {
+            private_key_pem: String::from_utf8(key.private_key_to_pem_pkcs8().map_unexpected()?)
+                .map_unexpected()?,
+            cert_pems: cert
                 .into_iter()
                 .map(|cert| {
                     let cert_pem = cert.to_pem().map_unexpected()?;
                     let cert_pem = String::from_utf8(cert_pem).map_unexpected()?;
                     Ok::<String, error::Unexpected>(cert_pem)
                 })
-            .try_collect()?;
+                .try_collect()?,
+        };
 
         let cert_file = fs::File::create(self.certificate_path(domain)).map_unexpected()?;
 
-        serde_json::to_writer(cert_file, &cert).map_unexpected()?;
+        serde_json::to_writer(cert_file, &to_store).map_unexpected()?;
 
         Ok(())
     }
 
-    fn get_certificate(&self, domain: &str) -> Result<Vec<Certificate>, GetCertificateError> {
+    fn get_certificate(
+        &self,
+        domain: &str,
+    ) -> Result<(PrivateKey, Vec<Certificate>), GetCertificateError> {
         let file = fs::File::open(self.certificate_path(domain)).map_err(|e| match e.kind() {
             io::ErrorKind::NotFound => GetCertificateError::NotFound,
             _ => e.to_unexpected().into(),
         })?;
 
-        let cert: Vec<String> = serde_json::from_reader(file).map_unexpected()?;
+        let stored: StoredPKeyCert = serde_json::from_reader(file).map_unexpected()?;
 
-        let cert: Vec<Certificate> = cert
+        let key =
+            PrivateKey::private_key_from_pem(stored.private_key_pem.as_bytes()).map_unexpected()?;
+
+        let cert: Vec<Certificate> = stored
+            .cert_pems
             .into_iter()
             .map(|cert| openssl::x509::X509::from_pem(cert.as_bytes()).map_unexpected())
             .try_collect()?;
 
-        Ok(cert)
+        Ok((key, cert))
     }
 }
 
@@ -187,7 +213,7 @@ mod tests {
 
         assert!(matches!(
             store.get_account_key(),
-            Err::<AccountKey, GetAccountKeyError>(GetAccountKeyError::NotFound)
+            Err::<PrivateKey, GetAccountKeyError>(GetAccountKeyError::NotFound)
         ));
 
         let k = acme2::gen_rsa_private_key(4096).expect("private key generated");