Rename tls_prf() to tls_prf_sha1_md5()

Prepare for multiple TLS PRF functions by renaming the SHA1+MD5 based
TLS PRF function to more specific name and add tls_prf() within the
internal TLS implementation as a wrapper for this for now.

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

src/crypto/sha1-tlsprf.c

@@ -20,7 +20,7 @@
 
 
 /**
- * tls_prf - Pseudo-Random Function for TLS (TLS-PRF, RFC 2246)
+ * tls_prf_sha1_md5 - Pseudo-Random Function for TLS (TLS-PRF, RFC 2246)
  * @secret: Key for PRF
  * @secret_len: Length of the key in bytes
  * @label: A unique label for each purpose of the PRF
@@ -33,8 +33,8 @@
  * This function is used to derive new, cryptographically separate keys from a
  * given key in TLS. This PRF is defined in RFC 2246, Chapter 5.
  */
-int tls_prf(const u8 *secret, size_t secret_len, const char *label,
-	    const u8 *seed, size_t seed_len, u8 *out, size_t outlen)
+int tls_prf_sha1_md5(const u8 *secret, size_t secret_len, const char *label,
+		     const u8 *seed, size_t seed_len, u8 *out, size_t outlen)
 {
 	size_t L_S1, L_S2, i;
 	const u8 *S1, *S2;

src/crypto/sha1.h

@@ -25,9 +25,9 @@ int sha1_prf(const u8 *key, size_t key_len, const char *label,
 	     const u8 *data, size_t data_len, u8 *buf, size_t buf_len);
 int sha1_t_prf(const u8 *key, size_t key_len, const char *label,
 	       const u8 *seed, size_t seed_len, u8 *buf, size_t buf_len);
-int __must_check tls_prf(const u8 *secret, size_t secret_len,
-			 const char *label, const u8 *seed, size_t seed_len,
-			 u8 *out, size_t outlen);
+int __must_check tls_prf_sha1_md5(const u8 *secret, size_t secret_len,
+				  const char *label, const u8 *seed,
+				  size_t seed_len, u8 *out, size_t outlen);
 int pbkdf2_sha1(const char *passphrase, const char *ssid, size_t ssid_len,
 		int iterations, u8 *buf, size_t buflen);
 #endif /* SHA1_H */

src/crypto/tls.h

@@ -305,7 +305,7 @@ int __must_check tls_connection_get_keys(void *tls_ctx,
  * not exported from the TLS library, tls_connection_prf() is required so that
  * further keying material can be derived from the master secret. If not
  * implemented, the function will still need to be defined, but it can just
- * return -1. Example implementation of this function is in tls_prf() function
+ * return -1. Example implementation of this function is in tls_prf_sha1_md5()
  * when it is called with seed set to client_random|server_random (or
  * server_random|client_random).
  */

src/eap_common/eap_fast_common.c

@@ -133,9 +133,9 @@ u8 * eap_fast_derive_key(void *ssl_ctx, struct tls_connection *conn,
 
 	wpa_hexdump_key(MSG_MSGDUMP, "EAP-FAST: master_secret for key "
 			"expansion", keys.master_key, keys.master_key_len);
-	if (tls_prf(keys.master_key, keys.master_key_len,
-		    label, rnd, keys.client_random_len +
-		    keys.server_random_len, out, block_size + len))
+	if (tls_prf_sha1_md5(keys.master_key, keys.master_key_len,
+			     label, rnd, keys.client_random_len +
+			     keys.server_random_len, out, block_size + len))
 		goto fail;
 	os_free(rnd);
 	os_memmove(out, out + block_size, len);

src/eap_peer/eap_tls_common.c

@@ -294,9 +294,9 @@ u8 * eap_peer_tls_derive_key(struct eap_sm *sm, struct eap_ssl_data *data,
 	os_memcpy(rnd + keys.client_random_len, keys.server_random,
 		  keys.server_random_len);
 
-	if (tls_prf(keys.master_key, keys.master_key_len,
-		    label, rnd, keys.client_random_len +
-		    keys.server_random_len, out, len))
+	if (tls_prf_sha1_md5(keys.master_key, keys.master_key_len,
+			     label, rnd, keys.client_random_len +
+			     keys.server_random_len, out, len))
 		goto fail;
 
 	os_free(rnd);

src/eap_server/eap_server_tls_common.c

@@ -94,9 +94,9 @@ u8 * eap_server_tls_derive_key(struct eap_sm *sm, struct eap_ssl_data *data,
 	os_memcpy(rnd + keys.client_random_len, keys.server_random,
 		  keys.server_random_len);
 
-	if (tls_prf(keys.master_key, keys.master_key_len,
-		    label, rnd, keys.client_random_len +
-		    keys.server_random_len, out, len))
+	if (tls_prf_sha1_md5(keys.master_key, keys.master_key_len,
+			     label, rnd, keys.client_random_len +
+			     keys.server_random_len, out, len))
 		goto fail;
 
 	os_free(rnd);

src/tls/tlsv1_common.c

@@ -15,6 +15,7 @@
 #include "includes.h"
 
 #include "common.h"
+#include "crypto/sha1.h"
 #include "x509v3.h"
 #include "tlsv1_common.h"
 
@@ -265,3 +266,11 @@ const char * tls_version_str(u16 ver)
 
 	return "?";
 }
+
+
+int tls_prf(const u8 *secret, size_t secret_len, const char *label,
+	    const u8 *seed, size_t seed_len, u8 *out, size_t outlen)
+{
+	return tls_prf_sha1_md5(secret, secret_len, label, seed, seed_len, out,
+				outlen);
+}

src/tls/tlsv1_common.h

@@ -220,5 +220,7 @@ void tls_verify_hash_add(struct tls_verify_hash *verify, const u8 *buf,
 void tls_verify_hash_free(struct tls_verify_hash *verify);
 int tls_version_ok(u16 ver);
 const char * tls_version_str(u16 ver);
+int tls_prf(const u8 *secret, size_t secret_len, const char *label,
+	    const u8 *seed, size_t seed_len, u8 *out, size_t outlen);
 
 #endif /* TLSV1_COMMON_H */

tests/test-sha1.c

@@ -137,8 +137,9 @@ static int test_eap_fast(void)
 	}
 
 	printf("- PRF (TLS, SHA1/MD5) test case / key_block\n");
-	if (tls_prf(master_secret, sizeof(master_secret), "key expansion",
-		    seed, sizeof(seed), buf, sizeof(key_block)) ||
+	if (tls_prf_sha1_md5(master_secret, sizeof(master_secret),
+			     "key expansion", seed, sizeof(seed),
+			     buf, sizeof(key_block)) ||
 	    memcmp(key_block, buf, sizeof(key_block)) != 0) {
 		printf("PRF test - FAILED!\n");
 		errors++;