OpenSSL: Use connection certificate chain with PKCS#12 extra certs

When using OpenSSL 1.0.2 or newer, this replaces the older
SSL_CTX_add_extra_chain_cert() design with SSL_add1_chain_cert() to keep
the extra chain certificates out from SSL_CTX and specific to each
connection. In addition, build and rearrange extra certificates with
SSL_build_cert_chain() to avoid incorrect certificates and incorrect
order of certificates in the TLS handshake.

Signed-off-by: Jouni Malinen <j@w1.fi>

diff --git a/src/crypto/tls_openssl.c b/src/crypto/tls_openssl.c
index d0baea6..22e9abb 100644 (file)
--- a/src/crypto/tls_openssl.c
+++ b/src/crypto/tls_openssl.c
@@ -2112,6 +2112,35 @@ static int tls_parse_pkcs12(SSL_CTX *ssl_ctx, SSL *ssl, PKCS12 *p12,
        }
 
        if (certs) {
+#if OPENSSL_VERSION_NUMBER >= 0x10002000L
+               SSL_clear_chain_certs(ssl);
+               while ((cert = sk_X509_pop(certs)) != NULL) {
+                       X509_NAME_oneline(X509_get_subject_name(cert), buf,
+                                         sizeof(buf));
+                       wpa_printf(MSG_DEBUG, "TLS: additional certificate"
+                                  " from PKCS12: subject='%s'", buf);
+                       if (SSL_add1_chain_cert(ssl, cert) != 1) {
+                               res = -1;
+                               break;
+                       }
+               }
+               sk_X509_free(certs);
+               res = SSL_build_cert_chain(ssl,
+                                          SSL_BUILD_CHAIN_FLAG_CHECK |
+                                          SSL_BUILD_CHAIN_FLAG_IGNORE_ERROR);
+               if (!res) {
+                       tls_show_errors(MSG_DEBUG, __func__,
+                                       "Failed to build certificate chain");
+               } else if (res == 2) {
+                       wpa_printf(MSG_DEBUG,
+                                  "TLS: Ignore certificate chain verification error when building chain with PKCS#12 extra certificates");
+               }
+               /*
+                * Try to continue regardless of result since it is possible for
+                * the extra certificates not to be required.
+                */
+               res = 0;
+#else /* OPENSSL_VERSION_NUMBER >= 0x10002000L */
 #if OPENSSL_VERSION_NUMBER >= 0x10001000L
                SSL_CTX_clear_extra_chain_certs(ssl_ctx);
 #endif /* OPENSSL_VERSION_NUMBER >= 0x10001000L */
@@ -2130,6 +2159,7 @@ static int tls_parse_pkcs12(SSL_CTX *ssl_ctx, SSL *ssl, PKCS12 *p12,
                        }
                }
                sk_X509_free(certs);
+#endif /* OPENSSL_VERSION_NUMBER >= 0x10002000L */
        }
 
        PKCS12_free(p12);