Make tls_connection_get_keyblock_size() internal to tls_*.c
This function exposes internal state of the TLS negotiated parameters
for the sole purpose of being able to implement PRF for EAP-FAST. Since
tls_connection_prf() is now taking care of all TLS-based key derivation
cases, it is cleaner to keep this detail internal to each tls_*.c
wrapper implementation.
Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
diff --git a/src/crypto/tls.h b/src/crypto/tls.h
index 97ed8c1..f9e2e10 100644
--- a/src/crypto/tls.h
+++ b/src/crypto/tls.h
@@ -323,6 +323,7 @@
* @label: Label (e.g., description of the key) for PRF
* @server_random_first: seed is 0 = client_random|server_random,
* 1 = server_random|client_random
+ * @skip_keyblock: Skip TLS key block from the beginning of PRF output
* @out: Buffer for output data from TLS-PRF
* @out_len: Length of the output buffer
* Returns: 0 on success, -1 on failure
@@ -340,6 +341,7 @@
struct tls_connection *conn,
const char *label,
int server_random_first,
+ int skip_keyblock,
u8 *out, size_t out_len);
/**
@@ -526,16 +528,6 @@
struct tls_connection *conn);
/**
- * tls_connection_get_keyblock_size - Get TLS key_block size
- * @tls_ctx: TLS context data from tls_init()
- * @conn: Connection context data from tls_connection_init()
- * Returns: Size of the key_block for the negotiated cipher suite or -1 on
- * failure
- */
-int tls_connection_get_keyblock_size(void *tls_ctx,
- struct tls_connection *conn);
-
-/**
* tls_capabilities - Get supported TLS capabilities
* @tls_ctx: TLS context data from tls_init()
* Returns: Bit field of supported TLS capabilities (TLS_CAPABILITY_*)
diff --git a/src/crypto/tls_gnutls.c b/src/crypto/tls_gnutls.c
index 65db6fc..c7f6464 100644
--- a/src/crypto/tls_gnutls.c
+++ b/src/crypto/tls_gnutls.c
@@ -747,9 +747,9 @@
int tls_connection_prf(void *tls_ctx, struct tls_connection *conn,
const char *label, int server_random_first,
- u8 *out, size_t out_len)
+ int skip_keyblock, u8 *out, size_t out_len)
{
- if (conn == NULL || conn->session == NULL)
+ if (conn == NULL || conn->session == NULL || skip_keyblock)
return -1;
return gnutls_prf(conn->session, os_strlen(label), label,
@@ -1476,14 +1476,6 @@
}
-int tls_connection_get_keyblock_size(void *tls_ctx,
- struct tls_connection *conn)
-{
- /* TODO */
- return -1;
-}
-
-
unsigned int tls_capabilities(void *tls_ctx)
{
return 0;
diff --git a/src/crypto/tls_internal.c b/src/crypto/tls_internal.c
index 0c955da..19a2d5a 100644
--- a/src/crypto/tls_internal.c
+++ b/src/crypto/tls_internal.c
@@ -348,25 +348,57 @@
}
-int tls_connection_prf(void *tls_ctx, struct tls_connection *conn,
- const char *label, int server_random_first,
- u8 *out, size_t out_len)
+static int tls_get_keyblock_size(struct tls_connection *conn)
{
#ifdef CONFIG_TLS_INTERNAL_CLIENT
+ if (conn->client)
+ return tlsv1_client_get_keyblock_size(conn->client);
+#endif /* CONFIG_TLS_INTERNAL_CLIENT */
+#ifdef CONFIG_TLS_INTERNAL_SERVER
+ if (conn->server)
+ return tlsv1_server_get_keyblock_size(conn->server);
+#endif /* CONFIG_TLS_INTERNAL_SERVER */
+ return -1;
+}
+
+
+int tls_connection_prf(void *tls_ctx, struct tls_connection *conn,
+ const char *label, int server_random_first,
+ int skip_keyblock, u8 *out, size_t out_len)
+{
+ int ret = -1, skip = 0;
+ u8 *tmp_out = NULL;
+ u8 *_out = out;
+
+ if (skip_keyblock) {
+ skip = tls_get_keyblock_size(conn);
+ if (skip < 0)
+ return -1;
+ tmp_out = os_malloc(skip + out_len);
+ if (!tmp_out)
+ return -1;
+ _out = tmp_out;
+ }
+
+#ifdef CONFIG_TLS_INTERNAL_CLIENT
if (conn->client) {
- return tlsv1_client_prf(conn->client, label,
- server_random_first,
- out, out_len);
+ ret = tlsv1_client_prf(conn->client, label,
+ server_random_first,
+ _out, out_len);
}
#endif /* CONFIG_TLS_INTERNAL_CLIENT */
#ifdef CONFIG_TLS_INTERNAL_SERVER
if (conn->server) {
- return tlsv1_server_prf(conn->server, label,
- server_random_first,
- out, out_len);
+ ret = tlsv1_server_prf(conn->server, label,
+ server_random_first,
+ _out, out_len);
}
#endif /* CONFIG_TLS_INTERNAL_SERVER */
- return -1;
+ if (ret == 0 && skip_keyblock)
+ os_memcpy(out, _out + skip, out_len);
+ bin_clear_free(tmp_out, skip);
+
+ return ret;
}
@@ -637,21 +669,6 @@
}
-int tls_connection_get_keyblock_size(void *tls_ctx,
- struct tls_connection *conn)
-{
-#ifdef CONFIG_TLS_INTERNAL_CLIENT
- if (conn->client)
- return tlsv1_client_get_keyblock_size(conn->client);
-#endif /* CONFIG_TLS_INTERNAL_CLIENT */
-#ifdef CONFIG_TLS_INTERNAL_SERVER
- if (conn->server)
- return tlsv1_server_get_keyblock_size(conn->server);
-#endif /* CONFIG_TLS_INTERNAL_SERVER */
- return -1;
-}
-
-
unsigned int tls_capabilities(void *tls_ctx)
{
return 0;
diff --git a/src/crypto/tls_none.c b/src/crypto/tls_none.c
index a6d210a..1b1ba56 100644
--- a/src/crypto/tls_none.c
+++ b/src/crypto/tls_none.c
@@ -87,7 +87,7 @@
int tls_connection_prf(void *tls_ctx, struct tls_connection *conn,
const char *label, int server_random_first,
- u8 *out, size_t out_len)
+ int skip_keyblock, u8 *out, size_t out_len)
{
return -1;
}
@@ -181,13 +181,6 @@
}
-int tls_connection_get_keyblock_size(void *tls_ctx,
- struct tls_connection *conn)
-{
- return -1;
-}
-
-
unsigned int tls_capabilities(void *tls_ctx)
{
return 0;
diff --git a/src/crypto/tls_openssl.c b/src/crypto/tls_openssl.c
index 00e4479..935add5 100644
--- a/src/crypto/tls_openssl.c
+++ b/src/crypto/tls_openssl.c
@@ -2643,9 +2643,43 @@
}
+static int openssl_get_keyblock_size(SSL *ssl)
+{
+ const EVP_CIPHER *c;
+ const EVP_MD *h;
+ int md_size;
+
+ if (ssl->enc_read_ctx == NULL || ssl->enc_read_ctx->cipher == NULL ||
+ ssl->read_hash == NULL)
+ return -1;
+
+ c = ssl->enc_read_ctx->cipher;
+#if OPENSSL_VERSION_NUMBER >= 0x00909000L
+ h = EVP_MD_CTX_md(ssl->read_hash);
+#else
+ h = conn->ssl->read_hash;
+#endif
+ if (h)
+ md_size = EVP_MD_size(h);
+#if OPENSSL_VERSION_NUMBER >= 0x10000000L
+ else if (ssl->s3)
+ md_size = ssl->s3->tmp.new_mac_secret_size;
+#endif
+ else
+ return -1;
+
+ wpa_printf(MSG_DEBUG, "OpenSSL: keyblock size: key_len=%d MD_size=%d "
+ "IV_len=%d", EVP_CIPHER_key_length(c), md_size,
+ EVP_CIPHER_iv_length(c));
+ return 2 * (EVP_CIPHER_key_length(c) +
+ md_size +
+ EVP_CIPHER_iv_length(c));
+}
+
+
static int openssl_tls_prf(void *tls_ctx, struct tls_connection *conn,
const char *label, int server_random_first,
- u8 *out, size_t out_len)
+ int skip_keyblock, u8 *out, size_t out_len)
{
#ifdef CONFIG_FIPS
wpa_printf(MSG_ERROR, "OpenSSL: TLS keys cannot be exported in FIPS "
@@ -2655,6 +2689,9 @@
SSL *ssl;
u8 *rnd;
int ret = -1;
+ int skip = 0;
+ u8 *tmp_out = NULL;
+ u8 *_out = out;
/*
* TLS library did not support key generation, so get the needed TLS
@@ -2670,6 +2707,16 @@
ssl->session->master_key == NULL)
return -1;
+ if (skip_keyblock) {
+ skip = openssl_get_keyblock_size(ssl);
+ if (skip < 0)
+ return -1;
+ tmp_out = os_malloc(skip + out_len);
+ if (!tmp_out)
+ return -1;
+ _out = tmp_out;
+ }
+
rnd = os_malloc(2 * SSL3_RANDOM_SIZE);
if (rnd == NULL)
return -1;
@@ -2688,9 +2735,12 @@
if (tls_prf_sha1_md5(ssl->session->master_key,
ssl->session->master_key_length,
label, rnd, 2 * SSL3_RANDOM_SIZE,
- out, out_len) == 0)
+ _out, skip + out_len) == 0)
ret = 0;
os_free(rnd);
+ if (ret == 0 && skip_keyblock)
+ os_memcpy(out, _out + skip, out_len);
+ bin_clear_free(tmp_out, skip);
return ret;
#endif /* CONFIG_FIPS */
@@ -2699,15 +2749,16 @@
int tls_connection_prf(void *tls_ctx, struct tls_connection *conn,
const char *label, int server_random_first,
- u8 *out, size_t out_len)
+ int skip_keyblock, u8 *out, size_t out_len)
{
#if OPENSSL_VERSION_NUMBER >= 0x10001000L
SSL *ssl;
if (conn == NULL)
return -1;
- if (server_random_first)
+ if (server_random_first || skip_keyblock)
return openssl_tls_prf(tls_ctx, conn, label,
- server_random_first, out, out_len);
+ server_random_first, skip_keyblock,
+ out, out_len);
ssl = conn->ssl;
if (SSL_export_keying_material(ssl, out, out_len, label,
os_strlen(label), NULL, 0, 0) == 1) {
@@ -2716,7 +2767,7 @@
}
#endif
return openssl_tls_prf(tls_ctx, conn, label, server_random_first,
- out, out_len);
+ skip_keyblock, out, out_len);
}
@@ -3569,43 +3620,6 @@
}
-int tls_connection_get_keyblock_size(void *tls_ctx,
- struct tls_connection *conn)
-{
- const EVP_CIPHER *c;
- const EVP_MD *h;
- int md_size;
-
- if (conn == NULL || conn->ssl == NULL ||
- conn->ssl->enc_read_ctx == NULL ||
- conn->ssl->enc_read_ctx->cipher == NULL ||
- conn->ssl->read_hash == NULL)
- return -1;
-
- c = conn->ssl->enc_read_ctx->cipher;
-#if OPENSSL_VERSION_NUMBER >= 0x00909000L
- h = EVP_MD_CTX_md(conn->ssl->read_hash);
-#else
- h = conn->ssl->read_hash;
-#endif
- if (h)
- md_size = EVP_MD_size(h);
-#if OPENSSL_VERSION_NUMBER >= 0x10000000L
- else if (conn->ssl->s3)
- md_size = conn->ssl->s3->tmp.new_mac_secret_size;
-#endif
- else
- return -1;
-
- wpa_printf(MSG_DEBUG, "OpenSSL: keyblock size: key_len=%d MD_size=%d "
- "IV_len=%d", EVP_CIPHER_key_length(c), md_size,
- EVP_CIPHER_iv_length(c));
- return 2 * (EVP_CIPHER_key_length(c) +
- md_size +
- EVP_CIPHER_iv_length(c));
-}
-
-
unsigned int tls_capabilities(void *tls_ctx)
{
return 0;
diff --git a/src/eap_common/eap_fast_common.c b/src/eap_common/eap_fast_common.c
index 5b41189..151cc78 100644
--- a/src/eap_common/eap_fast_common.c
+++ b/src/eap_common/eap_fast_common.c
@@ -97,24 +97,16 @@
const char *label, size_t len)
{
u8 *out;
- int block_size;
- block_size = tls_connection_get_keyblock_size(ssl_ctx, conn);
- if (block_size < 0)
- return NULL;
-
- out = os_malloc(block_size + len);
+ out = os_malloc(len);
if (out == NULL)
return NULL;
- if (tls_connection_prf(ssl_ctx, conn, label, 1, out, block_size + len))
- {
+ if (tls_connection_prf(ssl_ctx, conn, label, 1, 1, out, len)) {
os_free(out);
return NULL;
}
- os_memmove(out, out + block_size, len);
- os_memset(out + len, 0, block_size);
return out;
}
diff --git a/src/eap_peer/eap_tls_common.c b/src/eap_peer/eap_tls_common.c
index e5a6ee5..b1180d5 100644
--- a/src/eap_peer/eap_tls_common.c
+++ b/src/eap_peer/eap_tls_common.c
@@ -319,7 +319,8 @@
if (out == NULL)
return NULL;
- if (tls_connection_prf(data->ssl_ctx, data->conn, label, 0, out, len)) {
+ if (tls_connection_prf(data->ssl_ctx, data->conn, label, 0, 0,
+ out, len)) {
os_free(out);
return NULL;
}
diff --git a/src/eap_server/eap_server_tls_common.c b/src/eap_server/eap_server_tls_common.c
index 09f2a82..23498c9 100644
--- a/src/eap_server/eap_server_tls_common.c
+++ b/src/eap_server/eap_server_tls_common.c
@@ -106,7 +106,8 @@
if (out == NULL)
return NULL;
- if (tls_connection_prf(sm->ssl_ctx, data->conn, label, 0, out, len)) {
+ if (tls_connection_prf(sm->ssl_ctx, data->conn, label, 0, 0,
+ out, len)) {
os_free(out);
return NULL;
}
