Use X509_STORE for root certificate storage

ctz · ctz · commit ef8e9a39262c · 2025-04-22T11:46:13.000+01:00
In {client,server}.c, see that the effects of `SSL_CTX_load_verify_file`
can be observed via `SSL_CTX_get_cert_store`
diff --git a/src/lib.rs b/src/lib.rs
@@ -17,7 +17,7 @@ use rustls::pki_types::{CertificateDer, ServerName};
 use rustls::server::{Accepted, Acceptor, ProducesTickets};
 use rustls::{
     CipherSuite, ClientConfig, ClientConnection, Connection, HandshakeKind, ProtocolVersion,
-    RootCertStore, ServerConfig, SignatureScheme, SupportedProtocolVersion,
+    ServerConfig, SignatureScheme, SupportedProtocolVersion,
 };
 
 use not_thread_safe::NotThreadSafe;
@@ -416,7 +416,6 @@ pub struct SslContext {
     raw_options: u64,
     verify_mode: VerifyMode,
     verify_depth: c_int,
-    verify_roots: RootCertStore,
     verify_x509_store: x509::OwnedX509Store,
     alpn: Vec<Vec<u8>>,
     default_cert_file: Option<PathBuf>,
@@ -447,7 +446,6 @@ impl SslContext {
             raw_options: 0,
             verify_mode: VerifyMode::default(),
             verify_depth: -1,
-            verify_roots: RootCertStore::empty(),
             verify_x509_store: OwnedX509Store::default(),
             alpn: vec![],
             default_cert_file: None,
@@ -624,12 +622,7 @@ impl SslContext {
         &mut self,
         certs: Vec<CertificateDer<'static>>,
     ) -> Result<(), error::Error> {
-        for c in certs {
-            self.verify_roots
-                .add(c)
-                .map_err(error::Error::from_rustls)?;
-        }
-        Ok(())
+        self.verify_x509_store.add(certs)
     }
 
     fn get_x509_store(&self) -> *mut X509_STORE {
@@ -735,8 +728,8 @@ struct Ssl {
     mode: ConnMode,
     verify_mode: VerifyMode,
     verify_depth: c_int,
-    verify_roots: RootCertStore,
     verify_server_name: Option<ServerName<'static>>,
+    verify_x509_store: x509::OwnedX509Store,
     alpn: Vec<Vec<u8>>,
     alpn_callback: callbacks::AlpnCallbackConfig,
     cert_callback: callbacks::CertCallbackConfig,
@@ -776,8 +769,8 @@ impl Ssl {
             mode: inner.method.mode(),
             verify_mode: inner.verify_mode,
             verify_depth: inner.verify_depth,
-            verify_roots: Self::load_verify_certs(inner)?,
             verify_server_name: None,
+            verify_x509_store: Self::load_verify_certs(inner)?,
             alpn: inner.alpn.clone(),
             alpn_callback: inner.alpn_callback.clone(),
             cert_callback: inner.cert_callback.clone(),
@@ -1027,7 +1020,7 @@ impl Ssl {
 
         let provider = Arc::new(provider::default_provider());
         let verifier = Arc::new(verifier::ServerVerifier::new(
-            self.verify_roots.clone().into(),
+            self.verify_x509_store.clone(),
             provider.clone(),
             self.verify_mode,
             &self.verify_server_name,
@@ -1112,7 +1105,7 @@ impl Ssl {
         let provider = Arc::new(provider::default_provider());
         let verifier = Arc::new(
             verifier::ClientVerifier::new(
-                self.verify_roots.clone().into(),
+                &self.verify_x509_store,
                 provider.clone(),
                 self.verify_mode,
             )
@@ -1435,20 +1428,20 @@ impl Ssl {
         }
     }
 
-    fn load_verify_certs(ctx: &SslContext) -> Result<RootCertStore, error::Error> {
-        let mut verify_roots = ctx.verify_roots.clone();
-
+    fn load_verify_certs(ctx: &SslContext) -> Result<x509::OwnedX509Store, error::Error> {
         // If verify_roots isn't empty then it was configured with `SSL_CTX_load_verify_file`
         // or `SSL_CTX_load_verify_dir` and we should use it as-is.
-        if !ctx.verify_roots.is_empty() {
-            return Ok(verify_roots);
+        if !ctx.verify_x509_store.is_empty() {
+            return Ok(ctx.verify_x509_store.clone());
         }
 
         // Otherwise, try to load the default cert file or cert dir.
+        let mut verify_roots = x509::OwnedX509Store::default();
+
         if let Some(default_cert_file) = &ctx.default_cert_file {
-            verify_roots.add_parsable_certificates(x509::load_certs(
+            verify_roots.add(x509::load_certs(
                 vec![default_cert_file.to_path_buf()].into_iter(),
-            )?);
+            )?)?;
         } else if let Some(default_cert_dir) = &ctx.default_cert_dir {
             let entries = match fs::read_dir(default_cert_dir) {
                 Ok(iter) => iter,
@@ -1457,7 +1450,7 @@ impl Ssl {
             .filter_map(|entry| entry.ok())
             .map(|dir_entry| dir_entry.path());
 
-            verify_roots.add_parsable_certificates(x509::load_certs(entries)?);
+            verify_roots.add(x509::load_certs(entries)?)?;
         }
 
         Ok(verify_roots)
diff --git a/src/miri.rs b/src/miri.rs
@@ -9,6 +9,16 @@ pub extern "C" fn X509_STORE_new() -> *mut X509_STORE {
     Box::into_raw(Box::new(X509_STORE(())))
 }
 
+#[no_mangle]
+pub extern "C" fn X509_STORE_get0_objects(s: *mut X509_STORE) -> *mut c_void {
+    ptr::null_mut()
+}
+
+#[no_mangle]
+pub extern "C" fn OPENSSL_sk_num(sk: *mut c_void) -> c_int {
+    0
+}
+
 #[no_mangle]
 pub extern "C" fn X509_STORE_free(ptr: *mut X509_STORE) {
     if ptr.is_null() {
diff --git a/src/verifier.rs b/src/verifier.rs
@@ -16,10 +16,10 @@ use rustls::{
     pki_types::{CertificateDer, ServerName, UnixTime},
     server::danger::{ClientCertVerified, ClientCertVerifier},
     server::{ParsedCertificate, WebPkiClientVerifier},
-    CertificateError, DigitallySignedStruct, DistinguishedName, Error, RootCertStore,
-    SignatureScheme,
+    CertificateError, DigitallySignedStruct, DistinguishedName, Error, SignatureScheme,
 };
 
+use crate::x509::OwnedX509Store;
 use crate::VerifyMode;
 
 /// This is a verifier that implements the selection of bad ideas from OpenSSL:
@@ -29,7 +29,7 @@ use crate::VerifyMode;
 /// - that the behaviour defaults to verifying nothing
 #[derive(Debug)]
 pub struct ServerVerifier {
-    root_store: Arc<RootCertStore>,
+    x509_store: OwnedX509Store,
 
     provider: Arc<CryptoProvider>,
 
@@ -47,13 +47,13 @@ pub struct ServerVerifier {
 
 impl ServerVerifier {
     pub fn new(
-        root_store: Arc<RootCertStore>,
+        x509_store: OwnedX509Store,
         provider: Arc<CryptoProvider>,
         mode: VerifyMode,
         hostname: &Option<ServerName<'static>>,
     ) -> Self {
         Self {
-            root_store,
+            x509_store,
             provider,
             verify_hostname: hostname.clone(),
             mode,
@@ -81,10 +81,11 @@ impl ServerVerifier {
         now: UnixTime,
     ) -> Result<(), Error> {
         let end_entity = ParsedCertificate::try_from(end_entity)?;
+        let root_store = self.x509_store.root_store()?;
 
         verify_server_cert_signed_by_trust_anchor(
             &end_entity,
-            &self.root_store,
+            &root_store,
             intermediates,
             now,
             self.provider.signature_verification_algorithms.all,
@@ -173,10 +174,12 @@ pub struct ClientVerifier {
 
 impl ClientVerifier {
     pub fn new(
-        root_store: Arc<RootCertStore>,
+        x509_store: &OwnedX509Store,
         provider: Arc<CryptoProvider>,
         mode: VerifyMode,
     ) -> Result<Self, Error> {
+        let root_store = x509_store.root_store()?;
+
         let (parent, initial_result) = if !mode.server_must_attempt_client_auth() {
             (Ok(WebPkiClientVerifier::no_client_auth()), X509_V_OK)
         } else {
diff --git a/src/x509.rs b/src/x509.rs
@@ -1,15 +1,18 @@
 use core::ffi::{c_int, c_long, c_void};
 use core::{ptr, slice};
 use std::path::PathBuf;
+use std::sync::Arc;
 use std::{fs, io};
 
 use openssl_sys::{
     d2i_X509, i2d_X509, stack_st_X509, OPENSSL_free, OPENSSL_sk_new_null, OPENSSL_sk_num,
-    OPENSSL_sk_push, OPENSSL_sk_value, X509_STORE_free, X509_STORE_new, X509_free, OPENSSL_STACK,
+    OPENSSL_sk_push, OPENSSL_sk_value, X509_STORE_add_cert, X509_STORE_free,
+    X509_STORE_get0_objects, X509_STORE_get1_all_certs, X509_STORE_new, X509_free, OPENSSL_STACK,
     X509, X509_STORE,
 };
 use rustls::pki_types::pem::PemObject;
 use rustls::pki_types::CertificateDer;
+use rustls::RootCertStore;
 
 use crate::error::Error;
 
@@ -233,6 +236,7 @@ impl Drop for OwnedX509 {
     }
 }
 
+#[derive(Debug)]
 pub struct OwnedX509Store {
     raw: *mut X509_STORE,
 }
@@ -246,6 +250,54 @@ impl OwnedX509Store {
     pub fn pointer(&self) -> *mut X509_STORE {
         self.raw
     }
+
+    pub fn len(&self) -> usize {
+        match unsafe { OPENSSL_sk_num(X509_STORE_get0_objects(self.raw) as *const OPENSSL_STACK) } {
+            -1 | 0 => 0,
+            i => i as usize,
+        }
+    }
+
+    pub fn is_empty(&self) -> bool {
+        self.len() == 0
+    }
+
+    pub fn add(
+        &mut self,
+        cert_ders: impl IntoIterator<Item = CertificateDer<'static>>,
+    ) -> Result<(), Error> {
+        for cert_der in cert_ders {
+            let item = OwnedX509::parse_der(cert_der.as_ref())
+                .ok_or_else(|| Error::bad_data("cannot parse certificate"))?;
+            match unsafe { X509_STORE_add_cert(self.raw, item.borrow_ref()) } {
+                1 => {}
+                _ => {
+                    return Err(Error::bad_data("cannot X509_STORE_add_cert"));
+                }
+            }
+        }
+
+        Ok(())
+    }
+
+    pub fn root_store(&self) -> Result<Arc<RootCertStore>, rustls::Error> {
+        let ptr = unsafe { X509_STORE_get1_all_certs(self.raw) };
+
+        if ptr.is_null() {
+            return Err(rustls::Error::General(
+                "cannot retrieve trusted certs".to_string(),
+            ));
+        }
+
+        let certs = OwnedX509Stack::new(ptr);
+        let mut ret = RootCertStore::empty();
+
+        for i in 0..certs.len() {
+            ret.add(certs.item(i).der_bytes().into())?;
+        }
+
+        Ok(ret.into())
+    }
 }
 
 impl Default for OwnedX509Store {
@@ -256,6 +308,15 @@ impl Default for OwnedX509Store {
     }
 }
 
+impl Clone for OwnedX509Store {
+    fn clone(&self) -> Self {
+        unsafe {
+            X509_STORE_up_ref(self.raw);
+        }
+        Self { raw: self.raw }
+    }
+}
+
 impl Drop for OwnedX509Store {
     fn drop(&mut self) {
         unsafe {
@@ -264,6 +325,9 @@ impl Drop for OwnedX509Store {
     }
 }
 
+unsafe impl Send for OwnedX509Store {}
+unsafe impl Sync for OwnedX509Store {}
+
 pub(crate) fn load_certs<'a>(
     file_names: impl Iterator<Item = PathBuf>,
 ) -> Result<Vec<CertificateDer<'a>>, Error> {
@@ -295,4 +359,5 @@ extern "C" {
     );
     fn OPENSSL_sk_dup(st: *const OPENSSL_STACK) -> *mut OPENSSL_STACK;
     fn X509_up_ref(x: *mut X509) -> c_int;
+    fn X509_STORE_up_ref(xs: *mut X509_STORE) -> c_int;
 }
diff --git a/tests/client.c b/tests/client.c
@@ -56,8 +56,12 @@ int main(int argc, char **argv) {
     dump_openssl_error_stack();
     assert(SSL_CTX_get_verify_mode(ctx) == SSL_VERIFY_PEER);
     assert(SSL_CTX_get_verify_callback(ctx) == NULL);
+    TRACE(sk_X509_OBJECT_num(
+        X509_STORE_get0_objects(SSL_CTX_get_cert_store(ctx))));
     TRACE(SSL_CTX_load_verify_file(ctx, cacert));
     dump_openssl_error_stack();
+    TRACE(sk_X509_OBJECT_num(
+        X509_STORE_get0_objects(SSL_CTX_get_cert_store(ctx))));
   }
   printf("SSL_CTX_get_verify_depth default %d\n",
          SSL_CTX_get_verify_depth(ctx));
diff --git a/tests/server.c b/tests/server.c
@@ -128,8 +128,12 @@ int main(int argc, char **argv) {
   if (strcmp(cacert, "unauth") != 0) {
     SSL_CTX_set_verify(ctx, SSL_VERIFY_PEER, NULL);
     dump_openssl_error_stack();
+    TRACE(sk_X509_OBJECT_num(
+        X509_STORE_get0_objects(SSL_CTX_get_cert_store(ctx))));
     TRACE(SSL_CTX_load_verify_file(ctx, cacert));
     dump_openssl_error_stack();
+    TRACE(sk_X509_OBJECT_num(
+        X509_STORE_get0_objects(SSL_CTX_get_cert_store(ctx))));
   } else {
     printf("client auth disabled\n");
   }
