[PATCH] Use keystore ENGINE for private key operations

[Kenny Root]

The new keystore ENGINE is usable to perform private key operations when
we can't get the actual private key data. This is the case when hardware
crypto is enabled: the private key never leaves the hardware.

Subsequently, we need to be able to talk to OpenSSL ENGINEs that aren't
PKCS#11 or OpenSC. This just changes a few #define variables to allow us
to talk to our keystore engine without having one of those enabled and
without using a PIN.

Change-Id: Iabab5077c3d167a1e13bc8ef8745dc59ad4d62f7
---
 src/crypto/tls_openssl.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/src/crypto/tls_openssl.c b/src/crypto/tls_openssl.c
index 772f0b2..aaa920b 100644
--- a/src/crypto/tls_openssl.c
+++ b/src/crypto/tls_openssl.c
@@ -10,9 +10,11 @@
 
 #ifndef CONFIG_SMARTCARD
 #ifndef OPENSSL_NO_ENGINE
+#ifndef ANDROID
 #define OPENSSL_NO_ENGINE
 #endif
 #endif
+#endif
 
 #include <openssl/ssl.h>
 #include <openssl/err.h>
@@ -793,16 +795,21 @@ static int tls_engine_init(struct tls_connection *conn, const char *engine_id,
 		wpa_printf(MSG_ERROR, "ENGINE: Engine ID not set");
 		return -1;
 	}
+#ifndef ANDROID
 	if (pin == NULL) {
 		wpa_printf(MSG_ERROR, "ENGINE: Smartcard PIN not set");
 		return -1;
 	}
+#endif
 	if (key_id == NULL) {
 		wpa_printf(MSG_ERROR, "ENGINE: Key Id not set");
 		return -1;
 	}
 
 	ERR_clear_error();
+#ifdef ANDROID
+	ENGINE_load_dynamic();
+#endif
 	conn->engine = ENGINE_by_id(engine_id);
 	if (!conn->engine) {
 		wpa_printf(MSG_ERROR, "ENGINE: engine %s not available [%s]",
@@ -817,11 +824,13 @@ static int tls_engine_init(struct tls_connection *conn, const char *engine_id,
 	}
 	wpa_printf(MSG_DEBUG, "ENGINE: engine initialized");
 
+#ifndef ANDROID
 	if (ENGINE_ctrl_cmd_string(conn->engine, "PIN", pin, 0) == 0) {
 		wpa_printf(MSG_ERROR, "ENGINE: cannot set pin [%s]",
 			   ERR_error_string(ERR_get_error(), NULL));
 		goto err;
 	}
+#endif
 	/* load private key first in-case PIN is required for cert */
 	conn->private_key = ENGINE_load_private_key(conn->engine,
 						    key_id, NULL, NULL);
-- 
1.8.4.1