TLS: Add build configuration for TLS v1.2 support

This allows the internal TLS implementation to be built for TLS v1.2
support. In addition to the build option, this changes the TLS PRF
based on the negotiated version number. Though, this commit does not
yet complete support for TLS v1.2.

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

hostapd/Makefile

@@ -440,6 +440,11 @@ ifdef CONFIG_TLSV11
 CFLAGS += -DCONFIG_TLSV11
 endif
 
+ifdef CONFIG_TLSV12
+CFLAGS += -DCONFIG_TLSV12
+NEED_SHA256=y
+endif
+
 ifeq ($(CONFIG_TLS), openssl)
 ifdef TLS_FUNCS
 OBJS += ../src/crypto/tls_openssl.o
@@ -519,6 +524,9 @@ OBJS += ../src/tls/pkcs8.o
 NEED_SHA256=y
 NEED_BASE64=y
 NEED_TLS_PRF=y
+ifdef CONFIG_TLSV12
+NEED_TLS_PRF_SHA256=y
+endif
 NEED_MODEXP=y
 NEED_CIPHER=y
 CFLAGS += -DCONFIG_TLS_INTERNAL

hostapd/defconfig

@@ -221,6 +221,10 @@ CONFIG_IPV6=y
 # are used.
 #CONFIG_TLSV11=y
 
+# TLS-based EAP methods require at least TLS v1.0. Newer version of TLS (v1.2)
+# can be enabled to enable use of stronger crypto algorithms.
+#CONFIG_TLSV12=y
+
 # If CONFIG_TLS=internal is used, additional library and include paths are
 # needed for LibTomMath. Alternatively, an integrated, minimal version of
 # LibTomMath can be used. See beginning of libtommath.c for details on benefits

src/tls/tlsv1_common.c

@@ -16,6 +16,7 @@
 
 #include "common.h"
 #include "crypto/sha1.h"
+#include "crypto/sha256.h"
 #include "x509v3.h"
 #include "tlsv1_common.h"
 
@@ -250,6 +251,10 @@ int tls_version_ok(u16 ver)
 	if (ver == TLS_VERSION_1_1)
 		return 1;
 #endif /* CONFIG_TLSV11 */
+#ifdef CONFIG_TLSV12
+	if (ver == TLS_VERSION_1_2)
+		return 1;
+#endif /* CONFIG_TLSV12 */
 
 	return 0;
 }
@@ -262,6 +267,8 @@ const char * tls_version_str(u16 ver)
 		return "1.0";
 	case TLS_VERSION_1_1:
 		return "1.1";
+	case TLS_VERSION_1_2:
+		return "1.2";
 	}
 
 	return "?";
@@ -271,6 +278,14 @@ const char * tls_version_str(u16 ver)
 int tls_prf(u16 ver, const u8 *secret, size_t secret_len, const char *label,
 	    const u8 *seed, size_t seed_len, u8 *out, size_t outlen)
 {
+#ifdef CONFIG_TLSV12
+	if (ver >= TLS_VERSION_1_2) {
+		tls_prf_sha256(secret, secret_len, label, seed, seed_len,
+			       out, outlen);
+		return 0;
+	}
+#endif /* CONFIG_TLSV12 */
+
 	return tls_prf_sha1_md5(secret, secret_len, label, seed, seed_len, out,
 				outlen);
 }

src/tls/tlsv1_common.h

@@ -19,11 +19,16 @@
 
 #define TLS_VERSION_1 0x0301 /* TLSv1 */
 #define TLS_VERSION_1_1 0x0302 /* TLSv1.1 */
+#define TLS_VERSION_1_2 0x0303 /* TLSv1.2 */
+#ifdef CONFIG_TLSV12
+#define TLS_VERSION TLS_VERSION_1_2
+#else /* CONFIG_TLSV12 */
 #ifdef CONFIG_TLSV11
 #define TLS_VERSION TLS_VERSION_1_1
 #else /* CONFIG_TLSV11 */
 #define TLS_VERSION TLS_VERSION_1
 #endif /* CONFIG_TLSV11 */
+#endif /* CONFIG_TLSV12 */
 #define TLS_RANDOM_LEN 32
 #define TLS_PRE_MASTER_SECRET_LEN 48
 #define TLS_MASTER_SECRET_LEN 48

wpa_supplicant/Makefile

@@ -827,6 +827,11 @@ ifdef CONFIG_TLSV11
 CFLAGS += -DCONFIG_TLSV11
 endif
 
+ifdef CONFIG_TLSV12
+CFLAGS += -DCONFIG_TLSV12
+NEED_SHA256=y
+endif
+
 ifeq ($(CONFIG_TLS), openssl)
 ifdef TLS_FUNCS
 CFLAGS += -DEAP_TLS_OPENSSL
@@ -911,6 +916,9 @@ OBJS += ../src/tls/pkcs8.o
 NEED_SHA256=y
 NEED_BASE64=y
 NEED_TLS_PRF=y
+ifdef CONFIG_TLSV12
+NEED_TLS_PRF_SHA256=y
+endif
 NEED_MODEXP=y
 NEED_CIPHER=y
 CFLAGS += -DCONFIG_TLS_INTERNAL_CLIENT

wpa_supplicant/defconfig

@@ -332,6 +332,13 @@ CONFIG_PEERKEY=y
 # sent prior to negotiating which version will be used)
 #CONFIG_TLSV11=y
 
+# TLS-based EAP methods require at least TLS v1.0. Newer version of TLS (v1.2)
+# can be enabled to enable use of stronger crypto algorithms. It should be
+# noted that some existing TLS v1.0 -based implementation may not be compatible
+# with TLS v1.2 message (ClientHello is sent prior to negotiating which version
+# will be used)
+#CONFIG_TLSV12=y
+
 # If CONFIG_TLS=internal is used, additional library and include paths are
 # needed for LibTomMath. Alternatively, an integrated, minimal version of
 # LibTomMath can be used. See beginning of libtommath.c for details on benefits