From 68db4ddab7d35f5a3df1beee9a95fe093682340b Mon Sep 17 00:00:00 2001 From: Matt Caswell Date: Fri, 25 Nov 2016 17:52:35 +0000 Subject: [PATCH] Add an extension initilisation and finalisation capability Perl changes reviewed by Richard Levitte. Non-perl changes reviewed by Rich Salz Reviewed-by: Rich Salz Reviewed-by: Richard Levitte --- ssl/statem/extensions.c | 79 +++++++++++++++++++++++++++++++++++++++-- 1 file changed, 77 insertions(+), 2 deletions(-) diff --git a/ssl/statem/extensions.c b/ssl/statem/extensions.c index 68e278c3e2..a50756a071 100644 --- a/ssl/statem/extensions.c +++ b/ssl/statem/extensions.c @@ -14,6 +14,11 @@ typedef struct { /* The ID for the extension */ unsigned int type; + /* + * Initialise extension before parsing. Always called even if extension not + * present + */ + int (*init_ext)(SSL *s, unsigned int context); /* Parse extension received by server from client */ int (*parse_client_ext)(SSL *s, PACKET *pkt, int *al); /* Parse extension received by client from server */ @@ -22,6 +27,11 @@ typedef struct { int (*construct_server_ext)(SSL *s, WPACKET *pkt, int *al); /* Construct extension sent by client */ int (*construct_client_ext)(SSL *s, WPACKET *pkt, int *al); + /* + * Finalise extension after parsing. Always called even if extension not + * present + */ + int (*finalise_ext)(SSL *s, unsigned int context); unsigned int context; } EXTENSION_DEFINITION; @@ -33,74 +43,89 @@ typedef struct { static const EXTENSION_DEFINITION ext_defs[] = { { TLSEXT_TYPE_renegotiate, + NULL, tls_parse_client_renegotiate, tls_parse_server_renegotiate, tls_construct_server_renegotiate, tls_construct_client_renegotiate, + NULL, EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO | EXT_SSL3_ALLOWED | EXT_TLS1_2_AND_BELOW_ONLY }, { TLSEXT_TYPE_server_name, + NULL, tls_parse_client_server_name, tls_parse_server_server_name, tls_construct_server_server_name, tls_construct_client_server_name, + NULL, EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO | EXT_TLS1_3_ENCRYPTED_EXTENSIONS }, #ifndef OPENSSL_NO_SRP { TLSEXT_TYPE_srp, + NULL, tls_parse_client_srp, NULL, NULL, tls_construct_client_srp, + NULL, EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO | EXT_TLS1_2_AND_BELOW_ONLY }, #endif #ifndef OPENSSL_NO_EC { TLSEXT_TYPE_ec_point_formats, + NULL, tls_parse_client_ec_pt_formats, tls_parse_server_ec_pt_formats, tls_construct_server_ec_pt_formats, tls_construct_client_ec_pt_formats, + NULL, EXT_CLIENT_HELLO | EXT_TLS1_2_AND_BELOW_ONLY }, { TLSEXT_TYPE_supported_groups, + NULL, tls_parse_client_supported_groups, NULL, NULL /* TODO(TLS1.3): Need to add this */, tls_construct_client_supported_groups, - EXT_CLIENT_HELLO - | EXT_TLS1_3_ENCRYPTED_EXTENSIONS + NULL, + EXT_CLIENT_HELLO | EXT_TLS1_3_ENCRYPTED_EXTENSIONS }, #endif { TLSEXT_TYPE_session_ticket, + NULL, tls_parse_client_session_ticket, tls_parse_server_session_ticket, tls_construct_server_session_ticket, tls_construct_client_session_ticket, + NULL, EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO | EXT_TLS1_2_AND_BELOW_ONLY }, { TLSEXT_TYPE_signature_algorithms, + NULL, tls_parse_client_sig_algs, NULL, NULL, tls_construct_client_sig_algs, + NULL, EXT_CLIENT_HELLO }, #ifndef OPENSSL_NO_OCSP { TLSEXT_TYPE_status_request, + NULL, tls_parse_client_status_request, tls_parse_server_status_request, tls_construct_server_status_request, tls_construct_client_status_request, + NULL, EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO | EXT_TLS1_3_CERTIFICATE }, @@ -108,44 +133,53 @@ static const EXTENSION_DEFINITION ext_defs[] = { #ifndef OPENSSL_NO_NEXTPROTONEG { TLSEXT_TYPE_next_proto_neg, + NULL, tls_parse_client_npn, tls_parse_server_npn, tls_construct_server_next_proto_neg, tls_construct_client_npn, + NULL, EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO | EXT_TLS1_2_AND_BELOW_ONLY }, #endif { TLSEXT_TYPE_application_layer_protocol_negotiation, + NULL, tls_parse_client_alpn, tls_parse_server_alpn, tls_construct_server_alpn, tls_construct_client_alpn, + NULL, EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO | EXT_TLS1_3_ENCRYPTED_EXTENSIONS }, #ifndef OPENSSL_NO_SRTP { TLSEXT_TYPE_use_srtp, + NULL, tls_parse_client_use_srtp, tls_parse_server_use_srtp, tls_construct_server_use_srtp, tls_construct_client_use_srtp, + NULL, EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO | EXT_TLS1_3_ENCRYPTED_EXTENSIONS | EXT_DTLS_ONLY }, #endif { TLSEXT_TYPE_encrypt_then_mac, + NULL, tls_parse_client_etm, tls_parse_server_etm, tls_construct_server_etm, tls_construct_client_etm, + NULL, EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO | EXT_TLS1_2_AND_BELOW_ONLY }, #ifndef OPENSSL_NO_CT { TLSEXT_TYPE_signed_certificate_timestamp, + NULL, /* * No server side support for this, but can be provided by a custom * extension. This is an exception to the rule that custom extensions @@ -155,33 +189,40 @@ static const EXTENSION_DEFINITION ext_defs[] = { tls_parse_server_sct, NULL, tls_construct_client_sct, + NULL, EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO | EXT_TLS1_3_CERTIFICATE }, #endif { TLSEXT_TYPE_extended_master_secret, + NULL, tls_parse_client_ems, tls_parse_server_ems, tls_construct_server_ems, tls_construct_client_ems, + NULL, EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO | EXT_TLS1_2_AND_BELOW_ONLY }, { TLSEXT_TYPE_supported_versions, + NULL, /* Processed inline as part of version selection */ NULL, NULL, NULL, tls_construct_client_supported_versions, + NULL, EXT_CLIENT_HELLO | EXT_TLS_IMPLEMENTATION_ONLY | EXT_TLS1_3_ONLY }, { TLSEXT_TYPE_key_share, + NULL, tls_parse_client_key_share, tls_parse_server_key_share, tls_construct_server_key_share, tls_construct_client_key_share, + NULL, EXT_CLIENT_HELLO | EXT_TLS1_3_SERVER_HELLO | EXT_TLS1_3_HELLO_RETRY_REQUEST | EXT_TLS_IMPLEMENTATION_ONLY | EXT_TLS1_3_ONLY @@ -194,18 +235,22 @@ static const EXTENSION_DEFINITION ext_defs[] = { TLSEXT_TYPE_cryptopro_bug, NULL, NULL, + NULL, tls_construct_server_cryptopro_bug, NULL, + NULL, EXT_TLS1_2_SERVER_HELLO | EXT_TLS1_2_AND_BELOW_ONLY }, { /* Last in the list because it must be added as the last extension */ TLSEXT_TYPE_padding, + NULL, /* We send this, but don't read it */ NULL, NULL, NULL, tls_construct_client_padding, + NULL, EXT_CLIENT_HELLO } }; @@ -362,6 +407,18 @@ int tls_collect_extensions(SSL *s, PACKET *packet, unsigned int context, } } + /* + * Initialise all known extensions relevant to this context, whether we have + * found them or not + */ + for (i = 0; i < OSSL_NELEM(ext_defs); i++) { + if(ext_defs[i].init_ext != NULL && (ext_defs[i].context & context) != 0 + && !ext_defs[i].init_ext(s, context)) { + *ad = SSL_AD_INTERNAL_ERROR; + goto err; + } + } + *res = raw_extensions; *numfound = num_extensions; return 1; @@ -371,6 +428,11 @@ int tls_collect_extensions(SSL *s, PACKET *packet, unsigned int context, return 0; } +/* + * Parse all remaining extensions that have not yet been parsed. Also calls the + * finalisation for all extensions at the end. Returns 1 for success or 0 for + * failure. On failure, |*al| is populated with a suitable alert code. + */ int tls_parse_all_extensions(SSL *s, int context, RAW_EXTENSION *exts, size_t numexts, int *al) { @@ -435,6 +497,19 @@ int tls_parse_all_extensions(SSL *s, int context, RAW_EXTENSION *exts, return 0; } + /* + * Finalise all known extensions relevant to this context, whether we have + * found them or not + */ + for (loop = 0; loop < OSSL_NELEM(ext_defs); loop++) { + if(ext_defs[loop].finalise_ext != NULL + && (ext_defs[loop].context & context) != 0 + && !ext_defs[loop].finalise_ext(s, context)) { + *al = SSL_AD_INTERNAL_ERROR; + return 0; + } + } + return 1; } -- 2.25.1