ssl_tls.c: Move some client specific functions to ssl_client.c
Signed-off-by: Ronald Cron <ronald.cron@arm.com>
diff --git a/library/ssl_client.c b/library/ssl_client.c
index 9a65b57..fa5b9f9 100644
--- a/library/ssl_client.c
+++ b/library/ssl_client.c
@@ -46,6 +46,76 @@
#include "ssl_tls13_keys.h"
#include "ssl_debug_helpers.h"
+#if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION)
+static int ssl_write_hostname_ext( mbedtls_ssl_context *ssl,
+ unsigned char *buf,
+ const unsigned char *end,
+ size_t *olen )
+{
+ unsigned char *p = buf;
+ size_t hostname_len;
+
+ *olen = 0;
+
+ if( ssl->hostname == NULL )
+ return( 0 );
+
+ MBEDTLS_SSL_DEBUG_MSG( 3,
+ ( "client hello, adding server name extension: %s",
+ ssl->hostname ) );
+
+ hostname_len = strlen( ssl->hostname );
+
+ MBEDTLS_SSL_CHK_BUF_PTR( p, end, hostname_len + 9 );
+
+ /*
+ * Sect. 3, RFC 6066 (TLS Extensions Definitions)
+ *
+ * In order to provide any of the server names, clients MAY include an
+ * extension of type "server_name" in the (extended) client hello. The
+ * "extension_data" field of this extension SHALL contain
+ * "ServerNameList" where:
+ *
+ * struct {
+ * NameType name_type;
+ * select (name_type) {
+ * case host_name: HostName;
+ * } name;
+ * } ServerName;
+ *
+ * enum {
+ * host_name(0), (255)
+ * } NameType;
+ *
+ * opaque HostName<1..2^16-1>;
+ *
+ * struct {
+ * ServerName server_name_list<1..2^16-1>
+ * } ServerNameList;
+ *
+ */
+ MBEDTLS_PUT_UINT16_BE( MBEDTLS_TLS_EXT_SERVERNAME, p, 0 );
+ p += 2;
+
+ MBEDTLS_PUT_UINT16_BE( hostname_len + 5, p, 0 );
+ p += 2;
+
+ MBEDTLS_PUT_UINT16_BE( hostname_len + 3, p, 0 );
+ p += 2;
+
+ *p++ = MBEDTLS_BYTE_0( MBEDTLS_TLS_EXT_SERVERNAME_HOSTNAME );
+
+ MBEDTLS_PUT_UINT16_BE( hostname_len, p, 0 );
+ p += 2;
+
+ memcpy( p, ssl->hostname, hostname_len );
+
+ *olen = hostname_len + 9;
+
+ return( 0 );
+}
+#endif /* MBEDTLS_SSL_SERVER_NAME_INDICATION */
+
#if defined(MBEDTLS_SSL_ALPN)
/*
* ssl_write_alpn_ext()
@@ -116,6 +186,233 @@
}
#endif /* MBEDTLS_SSL_ALPN */
+#if defined(MBEDTLS_ECDH_C) || defined(MBEDTLS_ECDSA_C) || \
+ defined(MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED)
+/*
+ * Function for writing a supported groups (TLS 1.3) or supported elliptic
+ * curves (TLS 1.2) extension.
+ *
+ * The "extension_data" field of a supported groups extension contains a
+ * "NamedGroupList" value (TLS 1.3 RFC8446):
+ * enum {
+ * secp256r1(0x0017), secp384r1(0x0018), secp521r1(0x0019),
+ * x25519(0x001D), x448(0x001E),
+ * ffdhe2048(0x0100), ffdhe3072(0x0101), ffdhe4096(0x0102),
+ * ffdhe6144(0x0103), ffdhe8192(0x0104),
+ * ffdhe_private_use(0x01FC..0x01FF),
+ * ecdhe_private_use(0xFE00..0xFEFF),
+ * (0xFFFF)
+ * } NamedGroup;
+ * struct {
+ * NamedGroup named_group_list<2..2^16-1>;
+ * } NamedGroupList;
+ *
+ * The "extension_data" field of a supported elliptic curves extension contains
+ * a "NamedCurveList" value (TLS 1.2 RFC 8422):
+ * enum {
+ * deprecated(1..22),
+ * secp256r1 (23), secp384r1 (24), secp521r1 (25),
+ * x25519(29), x448(30),
+ * reserved (0xFE00..0xFEFF),
+ * deprecated(0xFF01..0xFF02),
+ * (0xFFFF)
+ * } NamedCurve;
+ * struct {
+ * NamedCurve named_curve_list<2..2^16-1>
+ * } NamedCurveList;
+ *
+ * The TLS 1.3 supported groups extension was defined to be a compatible
+ * generalization of the TLS 1.2 supported elliptic curves extension. They both
+ * share the same extension identifier.
+ *
+ * DHE groups are not supported yet.
+ */
+static int ssl_write_supported_groups_ext( mbedtls_ssl_context *ssl,
+ unsigned char *buf,
+ const unsigned char *end,
+ size_t *out_len )
+{
+ unsigned char *p = buf ;
+ unsigned char *named_group_list; /* Start of named_group_list */
+ size_t named_group_list_len; /* Length of named_group_list */
+ const uint16_t *group_list = mbedtls_ssl_get_groups( ssl );
+
+ *out_len = 0;
+
+ MBEDTLS_SSL_DEBUG_MSG( 3, ( "client hello, adding supported_groups extension" ) );
+
+ /* Check if we have space for header and length fields:
+ * - extension_type (2 bytes)
+ * - extension_data_length (2 bytes)
+ * - named_group_list_length (2 bytes)
+ */
+ MBEDTLS_SSL_CHK_BUF_PTR( p, end, 6 );
+ p += 6;
+
+ named_group_list = p;
+
+ if( group_list == NULL )
+ return( MBEDTLS_ERR_SSL_BAD_CONFIG );
+
+ for( ; *group_list != 0; group_list++ )
+ {
+ MBEDTLS_SSL_DEBUG_MSG( 1, ( "got supported group(%04x)", *group_list ) );
+
+#if defined(MBEDTLS_ECP_C)
+ if( ( mbedtls_ssl_conf_is_tls13_enabled( ssl->conf ) &&
+ mbedtls_ssl_tls13_named_group_is_ecdhe( *group_list ) ) ||
+ ( mbedtls_ssl_conf_is_tls12_enabled( ssl->conf ) &&
+ mbedtls_ssl_tls12_named_group_is_ecdhe( *group_list ) ) )
+ {
+ const mbedtls_ecp_curve_info *curve_info;
+ curve_info = mbedtls_ecp_curve_info_from_tls_id( *group_list );
+ if( curve_info == NULL )
+ continue;
+ MBEDTLS_SSL_CHK_BUF_PTR( p, end, 2 );
+ MBEDTLS_PUT_UINT16_BE( *group_list, p, 0 );
+ p += 2;
+ MBEDTLS_SSL_DEBUG_MSG( 3, ( "NamedGroup: %s ( %x )",
+ curve_info->name, *group_list ) );
+ }
+#endif /* MBEDTLS_ECP_C */
+ /* Add DHE groups here */
+
+ }
+
+ /* Length of named_group_list */
+ named_group_list_len = p - named_group_list;
+ if( named_group_list_len == 0 )
+ {
+ MBEDTLS_SSL_DEBUG_MSG( 1, ( "No group available." ) );
+ return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
+ }
+
+ /* Write extension_type */
+ MBEDTLS_PUT_UINT16_BE( MBEDTLS_TLS_EXT_SUPPORTED_GROUPS, buf, 0 );
+ /* Write extension_data_length */
+ MBEDTLS_PUT_UINT16_BE( named_group_list_len + 2, buf, 2 );
+ /* Write length of named_group_list */
+ MBEDTLS_PUT_UINT16_BE( named_group_list_len, buf, 4 );
+
+ MBEDTLS_SSL_DEBUG_BUF( 3, "Supported groups extension",
+ buf + 4, named_group_list_len + 2 );
+
+ *out_len = p - buf;
+
+#if defined(MBEDTLS_SSL_PROTO_TLS1_3)
+ ssl->handshake->extensions_present |= MBEDTLS_SSL_EXT_SUPPORTED_GROUPS;
+#endif /* MBEDTLS_SSL_PROTO_TLS1_3 */
+
+ return( 0 );
+}
+
+#endif /* MBEDTLS_ECDH_C || MBEDTLS_ECDSA_C ||
+ MBEDTLS_KEY_EXCHANGE_ECJPAKE_ENABLED */
+
+#if defined(MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED)
+/*
+ * Function for writing a signature algorithm extension.
+ *
+ * The `extension_data` field of signature algorithm contains a `SignatureSchemeList`
+ * value (TLS 1.3 RFC8446):
+ * enum {
+ * ....
+ * ecdsa_secp256r1_sha256( 0x0403 ),
+ * ecdsa_secp384r1_sha384( 0x0503 ),
+ * ecdsa_secp521r1_sha512( 0x0603 ),
+ * ....
+ * } SignatureScheme;
+ *
+ * struct {
+ * SignatureScheme supported_signature_algorithms<2..2^16-2>;
+ * } SignatureSchemeList;
+ *
+ * The `extension_data` field of signature algorithm contains a `SignatureAndHashAlgorithm`
+ * value (TLS 1.2 RFC5246):
+ * enum {
+ * none(0), md5(1), sha1(2), sha224(3), sha256(4), sha384(5),
+ * sha512(6), (255)
+ * } HashAlgorithm;
+ *
+ * enum { anonymous(0), rsa(1), dsa(2), ecdsa(3), (255) }
+ * SignatureAlgorithm;
+ *
+ * struct {
+ * HashAlgorithm hash;
+ * SignatureAlgorithm signature;
+ * } SignatureAndHashAlgorithm;
+ *
+ * SignatureAndHashAlgorithm
+ * supported_signature_algorithms<2..2^16-2>;
+ *
+ * The TLS 1.3 signature algorithm extension was defined to be a compatible
+ * generalization of the TLS 1.2 signature algorithm extension.
+ * `SignatureAndHashAlgorithm` field of TLS 1.2 can be represented by
+ * `SignatureScheme` field of TLS 1.3
+ *
+ */
+static int ssl_write_sig_alg_ext( mbedtls_ssl_context *ssl, unsigned char *buf,
+ const unsigned char *end, size_t *out_len )
+{
+ unsigned char *p = buf;
+ unsigned char *supported_sig_alg; /* Start of supported_signature_algorithms */
+ size_t supported_sig_alg_len = 0; /* Length of supported_signature_algorithms */
+
+ *out_len = 0;
+
+ MBEDTLS_SSL_DEBUG_MSG( 3, ( "adding signature_algorithms extension" ) );
+
+ /* Check if we have space for header and length field:
+ * - extension_type (2 bytes)
+ * - extension_data_length (2 bytes)
+ * - supported_signature_algorithms_length (2 bytes)
+ */
+ MBEDTLS_SSL_CHK_BUF_PTR( p, end, 6 );
+ p += 6;
+
+ /*
+ * Write supported_signature_algorithms
+ */
+ supported_sig_alg = p;
+ const uint16_t *sig_alg = mbedtls_ssl_get_sig_algs( ssl );
+ if( sig_alg == NULL )
+ return( MBEDTLS_ERR_SSL_BAD_CONFIG );
+
+ for( ; *sig_alg != MBEDTLS_TLS1_3_SIG_NONE; sig_alg++ )
+ {
+ if( ! mbedtls_ssl_sig_alg_is_supported( ssl, *sig_alg ) )
+ continue;
+ MBEDTLS_SSL_CHK_BUF_PTR( p, end, 2 );
+ MBEDTLS_PUT_UINT16_BE( *sig_alg, p, 0 );
+ p += 2;
+ MBEDTLS_SSL_DEBUG_MSG( 3, ( "signature scheme [%x]", *sig_alg ) );
+ }
+
+ /* Length of supported_signature_algorithms */
+ supported_sig_alg_len = p - supported_sig_alg;
+ if( supported_sig_alg_len == 0 )
+ {
+ MBEDTLS_SSL_DEBUG_MSG( 1, ( "No signature algorithms defined." ) );
+ return( MBEDTLS_ERR_SSL_INTERNAL_ERROR );
+ }
+
+ /* Write extension_type */
+ MBEDTLS_PUT_UINT16_BE( MBEDTLS_TLS_EXT_SIG_ALG, buf, 0 );
+ /* Write extension_data_length */
+ MBEDTLS_PUT_UINT16_BE( supported_sig_alg_len + 2, buf, 2 );
+ /* Write length of supported_signature_algorithms */
+ MBEDTLS_PUT_UINT16_BE( supported_sig_alg_len, buf, 4 );
+
+ /* Output the total length of signature algorithms extension. */
+ *out_len = p - buf;
+
+#if defined(MBEDTLS_SSL_PROTO_TLS1_3)
+ ssl->handshake->extensions_present |= MBEDTLS_SSL_EXT_SIG_ALG;
+#endif /* MBEDTLS_SSL_PROTO_TLS1_3 */
+ return( 0 );
+}
+#endif /* MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED */
+
/* Write cipher_suites
* CipherSuite cipher_suites<2..2^16-2>;
*/
@@ -431,7 +728,7 @@
#if defined(MBEDTLS_SSL_SERVER_NAME_INDICATION)
/* Write server name extension */
- ret = mbedtls_ssl_write_hostname_ext( ssl, p, end, &output_len );
+ ret = ssl_write_hostname_ext( ssl, p, end, &output_len );
if( ret != 0 )
return( ret );
p += output_len;
@@ -467,7 +764,7 @@
#endif
0 )
{
- ret = mbedtls_ssl_write_supported_groups_ext( ssl, p, end, &output_len );
+ ret = ssl_write_supported_groups_ext( ssl, p, end, &output_len );
if( ret != 0 )
return( ret );
p += output_len;
@@ -484,7 +781,7 @@
#endif
0 )
{
- ret = mbedtls_ssl_write_sig_alg_ext( ssl, p, end, &output_len );
+ ret = ssl_write_sig_alg_ext( ssl, p, end, &output_len );
if( ret != 0 )
return( ret );
p += output_len;