ngtcp2: verify the server cert on connect (quictls)

Make ngtcp2+quictls correctly acknowledge `CURLOPT_SSL_VERIFYPEER` and
`CURLOPT_SSL_VERIFYHOST`.

The name check now uses a function from lib/vtls/openssl.c which will
need attention for when TLS is not done by OpenSSL or is disabled while
QUIC is enabled.

Possibly the servercert() function in openssl.c should be adjusted to be
able to use for both regular TLS and QUIC.

Ref: #8173
Closes #8178

diff --git a/lib/connect.c b/lib/connect.c
index c573875496843bfb4665d25a0e48634db0093d4b..5252f9714d00aa11335b0017d0041ce9bef109e0 100644 (file)
--- a/lib/connect.c
+++ b/lib/connect.c
@@ -894,6 +894,8 @@ CURLcode Curl_is_connected(struct Curl_easy *data,
         connkeep(conn, "HTTP/3 default");
         return CURLE_OK;
       }
+      /* When a QUIC connect attempt fails, the better error explanation is in
+         'result' and not in errno */
       if(result) {
         conn->tempsock[i] = CURL_SOCKET_BAD;
         error = SOCKERRNO;
@@ -977,6 +979,13 @@ CURLcode Curl_is_connected(struct Curl_easy *data,
         char buffer[STRERROR_LEN];
         Curl_printable_address(conn->tempaddr[i], ipaddress,
                                sizeof(ipaddress));
+#ifdef ENABLE_QUIC
+        if(conn->transport == TRNSPRT_QUIC) {
+          infof(data, "connect to %s port %u failed: %s",
+                ipaddress, conn->port, curl_easy_strerror(result));
+        }
+        else
+#endif
         infof(data, "connect to %s port %u failed: %s",
               ipaddress, conn->port,
               Curl_strerror(error, buffer, sizeof(buffer)));
@@ -988,9 +997,11 @@ CURLcode Curl_is_connected(struct Curl_easy *data,
         ainext(conn, i, TRUE);
         status = trynextip(data, conn, sockindex, i);
         if((status != CURLE_COULDNT_CONNECT) ||
-           conn->tempsock[other] == CURL_SOCKET_BAD)
+           conn->tempsock[other] == CURL_SOCKET_BAD) {
           /* the last attempt failed and no other sockets remain open */
-          result = status;
+          if(!result)
+            result = status;
+        }
       }
     }
   }
@@ -1016,6 +1027,7 @@ CURLcode Curl_is_connected(struct Curl_easy *data,
     /* no more addresses to try */
     const char *hostname;
     char buffer[STRERROR_LEN];
+    CURLcode failreason = result;
 
     /* if the first address family runs out of addresses to try before the
        happy eyeball timeout, go ahead and try the next family now */
@@ -1023,6 +1035,8 @@ CURLcode Curl_is_connected(struct Curl_easy *data,
     if(!result)
       return result;
 
+    result = failreason;
+
 #ifndef CURL_DISABLE_PROXY
     if(conn->bits.socksproxy)
       hostname = conn->socks_proxy.host.name;
@@ -1036,10 +1050,14 @@ CURLcode Curl_is_connected(struct Curl_easy *data,
       hostname = conn->host.name;
 
     failf(data, "Failed to connect to %s port %u after "
-                "%" CURL_FORMAT_TIMEDIFF_T " ms: %s",
-        hostname, conn->port,
-        Curl_timediff(now, data->progress.t_startsingle),
-        Curl_strerror(error, buffer, sizeof(buffer)));
+          "%" CURL_FORMAT_TIMEDIFF_T " ms: %s",
+          hostname, conn->port,
+          Curl_timediff(now, data->progress.t_startsingle),
+#ifdef ENABLE_QUIC
+          (conn->transport == TRNSPRT_QUIC) ?
+          curl_easy_strerror(result) :
+#endif
+          Curl_strerror(error, buffer, sizeof(buffer)));
 
     Curl_quic_disconnect(data, conn, 0);
     Curl_quic_disconnect(data, conn, 1);

diff --git a/lib/vquic/ngtcp2.c b/lib/vquic/ngtcp2.c
index dfe8f96fb114bd45eb5d4ed42e387eb1152959a4..b161a50612f83509ba957e92c58a4955b52afaf2 100644 (file)
--- a/lib/vquic/ngtcp2.c
+++ b/lib/vquic/ngtcp2.c
@@ -29,6 +29,7 @@
 #ifdef USE_OPENSSL
 #include <openssl/err.h>
 #include <ngtcp2/ngtcp2_crypto_openssl.h>
+#include "vtls/openssl.h"
 #elif defined(USE_GNUTLS)
 #include <ngtcp2/ngtcp2_crypto_gnutls.h>
 #endif
@@ -287,6 +288,27 @@ static SSL_CTX *quic_ssl_ctx(struct Curl_easy *data)
     SSL_CTX_set_keylog_callback(ssl_ctx, keylog_callback);
   }
 
+  {
+    struct connectdata *conn = data->conn;
+    const char * const ssl_cafile = conn->ssl_config.CAfile;
+    const char * const ssl_capath = conn->ssl_config.CApath;
+
+    if(conn->ssl_config.verifypeer) {
+      SSL_CTX_set_verify(ssl_ctx, SSL_VERIFY_PEER, NULL);
+      /* tell OpenSSL where to find CA certificates that are used to verify
+         the server's certificate. */
+      if(!SSL_CTX_load_verify_locations(ssl_ctx, ssl_cafile, ssl_capath)) {
+        /* Fail if we insist on successfully verifying the server. */
+        failf(data, "error setting certificate verify locations:"
+              "  CAfile: %s CApath: %s",
+              ssl_cafile ? ssl_cafile : "none",
+              ssl_capath ? ssl_capath : "none");
+        return NULL;
+      }
+      infof(data, " CAfile: %s", ssl_cafile ? ssl_cafile : "none");
+      infof(data, " CApath: %s", ssl_capath ? ssl_capath : "none");
+    }
+  }
   return ssl_ctx;
 }
 
@@ -1638,7 +1660,8 @@ static ssize_t ngh3_stream_send(struct Curl_easy *data,
   return sent;
 }
 
-static void ng_has_connected(struct connectdata *conn, int tempindex)
+static CURLcode ng_has_connected(struct Curl_easy *data,
+                                 struct connectdata *conn, int tempindex)
 {
   conn->recv[FIRSTSOCKET] = ngh3_stream_recv;
   conn->send[FIRSTSOCKET] = ngh3_stream_send;
@@ -1647,6 +1670,27 @@ static void ng_has_connected(struct connectdata *conn, int tempindex)
   conn->httpversion = 30;
   conn->bundle->multiuse = BUNDLE_MULTIPLEX;
   conn->quic = &conn->hequic[tempindex];
+
+#ifdef USE_OPENSSL
+  if(conn->ssl_config.verifyhost) {
+    X509 *server_cert;
+    CURLcode result;
+    server_cert = SSL_get_peer_certificate(conn->quic->ssl);
+    if(!server_cert) {
+      return CURLE_PEER_FAILED_VERIFICATION;
+    }
+    result = Curl_ossl_verifyhost(data, conn, server_cert);
+    X509_free(server_cert);
+    if(result)
+      return result;
+    infof(data, "Verified certificate just fine");
+  }
+  else
+    infof(data, "Skipped certificate verification");
+#else
+  (void)data;
+#endif
+  return CURLE_OK;
 }
 
 /*
@@ -1671,7 +1715,7 @@ CURLcode Curl_quic_is_connected(struct Curl_easy *data,
 
   if(ngtcp2_conn_get_handshake_completed(qs->qconn)) {
     *done = TRUE;
-    ng_has_connected(conn, sockindex);
+    result = ng_has_connected(data, conn, sockindex);
   }
 
   return result;
@@ -1718,6 +1762,10 @@ static CURLcode ng_process_ingress(struct Curl_easy *data,
     rv = ngtcp2_conn_read_pkt(qs->qconn, &path, &pi, buf, recvd, ts);
     if(rv) {
       /* TODO Send CONNECTION_CLOSE if possible */
+      if(rv == NGTCP2_ERR_CRYPTO)
+        /* this is a "TLS problem", but a failed certificate verification
+           is a common reason for this */
+        return CURLE_PEER_FAILED_VERIFICATION;
       return CURLE_RECV_ERROR;
     }
   }

diff --git a/lib/vtls/openssl.c b/lib/vtls/openssl.c
index 8fce068e47b98ce5aa571e877f5a089ca429c64f..e508d4813cb9e2ba6b3c52c23089a1bde0815dc0 100644 (file)
--- a/lib/vtls/openssl.c
+++ b/lib/vtls/openssl.c
@@ -1673,9 +1673,10 @@ static bool subj_alt_hostcheck(struct Curl_easy *data,
    hostname. In this case, the iPAddress subjectAltName must be present
    in the certificate and must exactly match the IP in the URI.
 
+   This function is now used from ngtcp2 (QUIC) as well.
 */
-static CURLcode verifyhost(struct Curl_easy *data, struct connectdata *conn,
-                           X509 *server_cert)
+CURLcode Curl_ossl_verifyhost(struct Curl_easy *data, struct connectdata *conn,
+                              X509 *server_cert)
 {
   bool matched = FALSE;
   int target = GEN_DNS; /* target type, GEN_DNS or GEN_IPADD */
@@ -3923,7 +3924,7 @@ static CURLcode servercert(struct Curl_easy *data,
   BIO_free(mem);
 
   if(SSL_CONN_CONFIG(verifyhost)) {
-    result = verifyhost(data, conn, backend->server_cert);
+    result = Curl_ossl_verifyhost(data, conn, backend->server_cert);
     if(result) {
       X509_free(backend->server_cert);
       backend->server_cert = NULL;

diff --git a/lib/vtls/openssl.h b/lib/vtls/openssl.h
index 2f6e1b2db8ea9ea8cffbdb7099867a8373357c2d..28058453c0b37ec2ca9174862723e9e6fbb8b54d 100644 (file)
--- a/lib/vtls/openssl.h
+++ b/lib/vtls/openssl.h
@@ -7,7 +7,7 @@
  *                            | (__| |_| |  _ <| |___
  *                             \___|\___/|_| \_\_____|
  *
- * Copyright (C) 1998 - 2020, Daniel Stenberg, <daniel@haxx.se>, et al.
+ * Copyright (C) 1998 - 2021, Daniel Stenberg, <daniel@haxx.se>, et al.
  *
  * This software is licensed as described in the file COPYING, which
  * you should have received as part of this distribution. The terms
@@ -26,11 +26,15 @@
 
 #ifdef USE_OPENSSL
 /*
- * This header should only be needed to get included by vtls.c and openssl.c
+ * This header should only be needed to get included by vtls.c, openssl.c
+ * and ngtcp2.c
  */
 
+#include <openssl/x509v3.h>
 #include "urldata.h"
 
+CURLcode Curl_ossl_verifyhost(struct Curl_easy *data, struct connectdata *conn,
+                              X509 *server_cert);
 extern const struct Curl_ssl Curl_ssl_openssl;
 
 #endif /* USE_OPENSSL */