From d3edc86720ab3dcb6209ae57811a5d11dd5ec1fe Mon Sep 17 00:00:00 2001 From: Paul Bakker Date: Wed, 20 Mar 2013 16:07:17 +0100 Subject: [PATCH] Moved writing of client extensions to separate functions in ssl_cli.c --- library/ssl_cli.c | 408 +++++++++++++++++++++++++--------------------- 1 file changed, 224 insertions(+), 184 deletions(-) diff --git a/library/ssl_cli.c b/library/ssl_cli.c index dae98fa21..65baef4bb 100644 --- a/library/ssl_cli.c +++ b/library/ssl_cli.c @@ -38,19 +38,223 @@ #include "polarssl/sha4.h" #endif +static void ssl_write_hostname_ext( ssl_context *ssl, + unsigned char *buf, + size_t *olen ) +{ + unsigned char *p = buf; + + *olen = 0; + + if ( ssl->hostname == NULL ) + return; + + SSL_DEBUG_MSG( 3, ( "client hello, adding server name extension: %s", + ssl->hostname ) ); + + /* + * 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; + */ + *p++ = (unsigned char)( ( TLS_EXT_SERVERNAME >> 8 ) & 0xFF ); + *p++ = (unsigned char)( ( TLS_EXT_SERVERNAME ) & 0xFF ); + + *p++ = (unsigned char)( ( (ssl->hostname_len + 5) >> 8 ) & 0xFF ); + *p++ = (unsigned char)( ( (ssl->hostname_len + 5) ) & 0xFF ); + + *p++ = (unsigned char)( ( (ssl->hostname_len + 3) >> 8 ) & 0xFF ); + *p++ = (unsigned char)( ( (ssl->hostname_len + 3) ) & 0xFF ); + + *p++ = (unsigned char)( ( TLS_EXT_SERVERNAME_HOSTNAME ) & 0xFF ); + *p++ = (unsigned char)( ( ssl->hostname_len >> 8 ) & 0xFF ); + *p++ = (unsigned char)( ( ssl->hostname_len ) & 0xFF ); + + memcpy( p, ssl->hostname, ssl->hostname_len ); + + *olen = ssl->hostname_len + 9; +} + +static void ssl_write_renegotiation_ext( ssl_context *ssl, + unsigned char *buf, + size_t *olen ) +{ + unsigned char *p = buf; + + *olen = 0; + + if( ssl->renegotiation != SSL_RENEGOTIATION ) + return; + + SSL_DEBUG_MSG( 3, ( "client hello, adding renegotiation extension" ) ); + + /* + * Secure renegotiation + */ + *p++ = (unsigned char)( ( TLS_EXT_RENEGOTIATION_INFO >> 8 ) & 0xFF ); + *p++ = (unsigned char)( ( TLS_EXT_RENEGOTIATION_INFO ) & 0xFF ); + + *p++ = 0x00; + *p++ = ( ssl->verify_data_len + 1 ) & 0xFF; + *p++ = ssl->verify_data_len & 0xFF; + + memcpy( p, ssl->own_verify_data, ssl->verify_data_len ); + + *olen = 5 + ssl->verify_data_len; +} + +static void ssl_write_signature_algorithms_ext( ssl_context *ssl, + unsigned char *buf, + size_t *olen ) +{ + unsigned char *p = buf; + unsigned char sig_alg_list[20]; + size_t sig_alg_len = 0; + + *olen = 0; + + if( ssl->max_minor_ver != SSL_MINOR_VERSION_3 ) + return; + + SSL_DEBUG_MSG( 3, ( "client hello, adding signature_algorithms extension" ) ); + + /* + * Prepare signature_algorithms extension (TLS 1.2) + */ +#if defined(POLARSSL_SHA4_C) + sig_alg_list[sig_alg_len++] = SSL_HASH_SHA512; + sig_alg_list[sig_alg_len++] = SSL_SIG_RSA; + sig_alg_list[sig_alg_len++] = SSL_HASH_SHA384; + sig_alg_list[sig_alg_len++] = SSL_SIG_RSA; +#endif +#if defined(POLARSSL_SHA2_C) + sig_alg_list[sig_alg_len++] = SSL_HASH_SHA256; + sig_alg_list[sig_alg_len++] = SSL_SIG_RSA; + sig_alg_list[sig_alg_len++] = SSL_HASH_SHA224; + sig_alg_list[sig_alg_len++] = SSL_SIG_RSA; +#endif +#if defined(POLARSSL_SHA1_C) + sig_alg_list[sig_alg_len++] = SSL_HASH_SHA1; + sig_alg_list[sig_alg_len++] = SSL_SIG_RSA; +#endif +#if defined(POLARSSL_MD5_C) + sig_alg_list[sig_alg_len++] = SSL_HASH_MD5; + sig_alg_list[sig_alg_len++] = SSL_SIG_RSA; +#endif + + /* + * 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>; + */ + *p++ = (unsigned char)( ( TLS_EXT_SIG_ALG >> 8 ) & 0xFF ); + *p++ = (unsigned char)( ( TLS_EXT_SIG_ALG ) & 0xFF ); + + *p++ = (unsigned char)( ( ( sig_alg_len + 2 ) >> 8 ) & 0xFF ); + *p++ = (unsigned char)( ( ( sig_alg_len + 2 ) ) & 0xFF ); + + *p++ = (unsigned char)( ( sig_alg_len >> 8 ) & 0xFF ); + *p++ = (unsigned char)( ( sig_alg_len ) & 0xFF ); + + memcpy( p, sig_alg_list, sig_alg_len ); + + *olen = 6 + sig_alg_len; +} + +#if defined(POLARSSL_ECDH_C) +static void ssl_write_supported_elliptic_curves_ext( ssl_context *ssl, + unsigned char *buf, + size_t *olen ) +{ + unsigned char *p = buf; + unsigned char elliptic_curve_list[20]; + size_t elliptic_curve_len = 0; + + *olen = 0; + + SSL_DEBUG_MSG( 3, ( "client hello, adding supported_elliptic_curves extension" ) ); + + elliptic_curve_list[elliptic_curve_len++] = 0x00; + elliptic_curve_list[elliptic_curve_len++] = POLARSSL_ECP_DP_SECP521R1; + elliptic_curve_list[elliptic_curve_len++] = 0x00; + elliptic_curve_list[elliptic_curve_len++] = POLARSSL_ECP_DP_SECP384R1; + elliptic_curve_list[elliptic_curve_len++] = 0x00; + elliptic_curve_list[elliptic_curve_len++] = POLARSSL_ECP_DP_SECP256R1; + elliptic_curve_list[elliptic_curve_len++] = 0x00; + elliptic_curve_list[elliptic_curve_len++] = POLARSSL_ECP_DP_SECP224R1; + elliptic_curve_list[elliptic_curve_len++] = 0x00; + elliptic_curve_list[elliptic_curve_len++] = POLARSSL_ECP_DP_SECP192R1; + + *p++ = (unsigned char)( ( TLS_EXT_SUPPORTED_ELLIPTIC_CURVES >> 8 ) & 0xFF ); + *p++ = (unsigned char)( ( TLS_EXT_SUPPORTED_ELLIPTIC_CURVES ) & 0xFF ); + + *p++ = (unsigned char)( ( ( elliptic_curve_len + 2 ) >> 8 ) & 0xFF ); + *p++ = (unsigned char)( ( ( elliptic_curve_len + 2 ) ) & 0xFF ); + + *p++ = (unsigned char)( ( ( elliptic_curve_len ) >> 8 ) & 0xFF ); + *p++ = (unsigned char)( ( ( elliptic_curve_len ) ) & 0xFF ); + + memcpy( p, elliptic_curve_list, elliptic_curve_len ); + + *olen = 6 + elliptic_curve_len; +} + +static void ssl_write_supported_point_formats_ext( ssl_context *ssl, + unsigned char *buf, + size_t *olen ) +{ + unsigned char *p = buf; + + *olen = 0; + + SSL_DEBUG_MSG( 3, ( "client hello, adding supported_point_formats extension" ) ); + + *p++ = (unsigned char)( ( TLS_EXT_SUPPORTED_POINT_FORMATS >> 8 ) & 0xFF ); + *p++ = (unsigned char)( ( TLS_EXT_SUPPORTED_POINT_FORMATS ) & 0xFF ); + + *p++ = 0x00; + *p++ = 3; + + *p++ = 2; + *p++ = POLARSSL_ECP_PF_COMPRESSED; + *p++ = POLARSSL_ECP_PF_UNCOMPRESSED; + + *olen = 7; +} +#endif + static int ssl_write_client_hello( ssl_context *ssl ) { int ret; - size_t i, n, ext_len = 0; + size_t i, n, olen, ext_len = 0; unsigned char *buf; unsigned char *p; time_t t; - unsigned char sig_alg_list[20]; - size_t sig_alg_len = 0; -#if defined(POLARSSL_ECDH_C) - unsigned char elliptic_curve_list[20]; - size_t elliptic_curve_len = 0; -#endif SSL_DEBUG_MSG( 2, ( "=> write client hello" ) ); @@ -165,66 +369,23 @@ static int ssl_write_client_hello( ssl_context *ssl ) *p++ = SSL_COMPRESS_NULL; #endif - if ( ssl->hostname != NULL ) - { - SSL_DEBUG_MSG( 3, ( "client hello, prepping for server name extension: %s", - ssl->hostname ) ); + // First write extensions, then the total length + // + ssl_write_hostname_ext( ssl, p + 2 + ext_len, &olen ); + ext_len += olen; - ext_len += ssl->hostname_len + 9; - } + ssl_write_renegotiation_ext( ssl, p + 2 + ext_len, &olen ); + ext_len += olen; - if( ssl->renegotiation == SSL_RENEGOTIATION ) - { - SSL_DEBUG_MSG( 3, ( "client hello, prepping for renegotiation extension" ) ); - ext_len += 5 + ssl->verify_data_len; - } - - /* - * Prepare signature_algorithms extension (TLS 1.2) - */ - if( ssl->max_minor_ver == SSL_MINOR_VERSION_3 ) - { -#if defined(POLARSSL_SHA4_C) - sig_alg_list[sig_alg_len++] = SSL_HASH_SHA512; - sig_alg_list[sig_alg_len++] = SSL_SIG_RSA; - sig_alg_list[sig_alg_len++] = SSL_HASH_SHA384; - sig_alg_list[sig_alg_len++] = SSL_SIG_RSA; -#endif -#if defined(POLARSSL_SHA2_C) - sig_alg_list[sig_alg_len++] = SSL_HASH_SHA256; - sig_alg_list[sig_alg_len++] = SSL_SIG_RSA; - sig_alg_list[sig_alg_len++] = SSL_HASH_SHA224; - sig_alg_list[sig_alg_len++] = SSL_SIG_RSA; -#endif -#if defined(POLARSSL_SHA1_C) - sig_alg_list[sig_alg_len++] = SSL_HASH_SHA1; - sig_alg_list[sig_alg_len++] = SSL_SIG_RSA; -#endif -#if defined(POLARSSL_MD5_C) - sig_alg_list[sig_alg_len++] = SSL_HASH_MD5; - sig_alg_list[sig_alg_len++] = SSL_SIG_RSA; -#endif - ext_len += 6 + sig_alg_len; - } + ssl_write_signature_algorithms_ext( ssl, p + 2 + ext_len, &olen ); + ext_len += olen; #if defined(POLARSSL_ECDH_C) - SSL_DEBUG_MSG( 3, ( "client hello, prepping for supported elliptic curves extension" ) ); + ssl_write_supported_elliptic_curves_ext( ssl, p + 2 + ext_len, &olen ); + ext_len += olen; - elliptic_curve_list[elliptic_curve_len++] = 0x00; - elliptic_curve_list[elliptic_curve_len++] = POLARSSL_ECP_DP_SECP521R1; - elliptic_curve_list[elliptic_curve_len++] = 0x00; - elliptic_curve_list[elliptic_curve_len++] = POLARSSL_ECP_DP_SECP384R1; - elliptic_curve_list[elliptic_curve_len++] = 0x00; - elliptic_curve_list[elliptic_curve_len++] = POLARSSL_ECP_DP_SECP256R1; - elliptic_curve_list[elliptic_curve_len++] = 0x00; - elliptic_curve_list[elliptic_curve_len++] = POLARSSL_ECP_DP_SECP224R1; - elliptic_curve_list[elliptic_curve_len++] = 0x00; - elliptic_curve_list[elliptic_curve_len++] = POLARSSL_ECP_DP_SECP192R1; - - ext_len += 6 + elliptic_curve_len; - - SSL_DEBUG_MSG( 3, ( "client hello, prepping for supported point formats extension" ) ); - ext_len += 7; + ssl_write_supported_point_formats_ext( ssl, p + 2 + ext_len, &olen ); + ext_len += olen; #endif SSL_DEBUG_MSG( 3, ( "client hello, total extension length: %d", @@ -232,128 +393,7 @@ static int ssl_write_client_hello( ssl_context *ssl ) *p++ = (unsigned char)( ( ext_len >> 8 ) & 0xFF ); *p++ = (unsigned char)( ( ext_len ) & 0xFF ); - - if ( ssl->hostname != NULL ) - { - /* - * 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; - */ - SSL_DEBUG_MSG( 3, ( "client hello, adding server name extension: %s", - ssl->hostname ) ); - - *p++ = (unsigned char)( ( TLS_EXT_SERVERNAME >> 8 ) & 0xFF ); - *p++ = (unsigned char)( ( TLS_EXT_SERVERNAME ) & 0xFF ); - - *p++ = (unsigned char)( ( (ssl->hostname_len + 5) >> 8 ) & 0xFF ); - *p++ = (unsigned char)( ( (ssl->hostname_len + 5) ) & 0xFF ); - - *p++ = (unsigned char)( ( (ssl->hostname_len + 3) >> 8 ) & 0xFF ); - *p++ = (unsigned char)( ( (ssl->hostname_len + 3) ) & 0xFF ); - - *p++ = (unsigned char)( ( TLS_EXT_SERVERNAME_HOSTNAME ) & 0xFF ); - *p++ = (unsigned char)( ( ssl->hostname_len >> 8 ) & 0xFF ); - *p++ = (unsigned char)( ( ssl->hostname_len ) & 0xFF ); - - memcpy( p, ssl->hostname, ssl->hostname_len ); - p += ssl->hostname_len; - } - - if( ssl->renegotiation == SSL_RENEGOTIATION ) - { - /* - * Secure renegotiation - */ - SSL_DEBUG_MSG( 3, ( "client hello, renegotiation info extension" ) ); - - *p++ = (unsigned char)( ( TLS_EXT_RENEGOTIATION_INFO >> 8 ) & 0xFF ); - *p++ = (unsigned char)( ( TLS_EXT_RENEGOTIATION_INFO ) & 0xFF ); - - *p++ = 0x00; - *p++ = ( ssl->verify_data_len + 1 ) & 0xFF; - *p++ = ssl->verify_data_len & 0xFF; - - memcpy( p, ssl->own_verify_data, ssl->verify_data_len ); - p += ssl->verify_data_len; - } - - if( ssl->max_minor_ver == SSL_MINOR_VERSION_3 ) - { - /* - * 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>; - */ - SSL_DEBUG_MSG( 3, ( "client hello, adding signature_algorithms extension" ) ); - - *p++ = (unsigned char)( ( TLS_EXT_SIG_ALG >> 8 ) & 0xFF ); - *p++ = (unsigned char)( ( TLS_EXT_SIG_ALG ) & 0xFF ); - - *p++ = (unsigned char)( ( ( sig_alg_len + 2 ) >> 8 ) & 0xFF ); - *p++ = (unsigned char)( ( ( sig_alg_len + 2 ) ) & 0xFF ); - - *p++ = (unsigned char)( ( sig_alg_len >> 8 ) & 0xFF ); - *p++ = (unsigned char)( ( sig_alg_len ) & 0xFF ); - - memcpy( p, sig_alg_list, sig_alg_len ); - - p += sig_alg_len; - } - -#if defined(POLARSSL_ECDH_C) - SSL_DEBUG_MSG( 3, ( "client hello, adding supported_elliptic_curves extension" ) ); - - *p++ = (unsigned char)( ( TLS_EXT_SUPPORTED_ELLIPTIC_CURVES >> 8 ) & 0xFF ); - *p++ = (unsigned char)( ( TLS_EXT_SUPPORTED_ELLIPTIC_CURVES ) & 0xFF ); - - *p++ = (unsigned char)( ( ( elliptic_curve_len + 2 ) >> 8 ) & 0xFF ); - *p++ = (unsigned char)( ( ( elliptic_curve_len + 2 ) ) & 0xFF ); - - *p++ = (unsigned char)( ( ( elliptic_curve_len ) >> 8 ) & 0xFF ); - *p++ = (unsigned char)( ( ( elliptic_curve_len ) ) & 0xFF ); - - memcpy( p, elliptic_curve_list, elliptic_curve_len ); - - p+= elliptic_curve_len; - - SSL_DEBUG_MSG( 3, ( "client hello, adding supported_point_formats extension" ) ); - - *p++ = (unsigned char)( ( TLS_EXT_SUPPORTED_POINT_FORMATS >> 8 ) & 0xFF ); - *p++ = (unsigned char)( ( TLS_EXT_SUPPORTED_POINT_FORMATS ) & 0xFF ); - - *p++ = 0x00; - *p++ = 3; - - *p++ = 2; - *p++ = POLARSSL_ECP_PF_COMPRESSED; - *p++ = POLARSSL_ECP_PF_UNCOMPRESSED; -#endif + p += ext_len; ssl->out_msglen = p - buf; ssl->out_msgtype = SSL_MSG_HANDSHAKE;