/*
- * Copyright 2016 The OpenSSL Project Authors. All Rights Reserved.
+ * Copyright 2016-2017 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the OpenSSL license (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
* https://www.openssl.org/source/license.html
*/
-#include <stdlib.h>
+#include <string.h>
#include "../ssl_locl.h"
#include "statem_locl.h"
-typedef struct {
- /* The ID for the extension */
+static int final_renegotiate(SSL *s, unsigned int context, int sent,
+ int *al);
+static int init_server_name(SSL *s, unsigned int context);
+static int final_server_name(SSL *s, unsigned int context, int sent,
+ int *al);
+#ifndef OPENSSL_NO_EC
+static int final_ec_pt_formats(SSL *s, unsigned int context, int sent,
+ int *al);
+#endif
+static int init_session_ticket(SSL *s, unsigned int context);
+#ifndef OPENSSL_NO_OCSP
+static int init_status_request(SSL *s, unsigned int context);
+#endif
+#ifndef OPENSSL_NO_NEXTPROTONEG
+static int init_npn(SSL *s, unsigned int context);
+#endif
+static int init_alpn(SSL *s, unsigned int context);
+static int final_alpn(SSL *s, unsigned int context, int sent, int *al);
+static int init_sig_algs(SSL *s, unsigned int context);
+static int init_certificate_authorities(SSL *s, unsigned int context);
+static EXT_RETURN tls_construct_certificate_authorities(SSL *s, WPACKET *pkt,
+ unsigned int context,
+ X509 *x,
+ size_t chainidx,
+ int *al);
+static int tls_parse_certificate_authorities(SSL *s, PACKET *pkt,
+ unsigned int context, X509 *x,
+ size_t chainidx, int *al);
+#ifndef OPENSSL_NO_SRP
+static int init_srp(SSL *s, unsigned int context);
+#endif
+static int init_etm(SSL *s, unsigned int context);
+static int init_ems(SSL *s, unsigned int context);
+static int final_ems(SSL *s, unsigned int context, int sent, int *al);
+static int init_psk_kex_modes(SSL *s, unsigned int context);
+#ifndef OPENSSL_NO_EC
+static int final_key_share(SSL *s, unsigned int context, int sent, int *al);
+#endif
+#ifndef OPENSSL_NO_SRTP
+static int init_srtp(SSL *s, unsigned int context);
+#endif
+static int final_sig_algs(SSL *s, unsigned int context, int sent, int *al);
+static int final_early_data(SSL *s, unsigned int context, int sent, int *al);
+
+/* Structure to define a built-in extension */
+typedef struct extensions_definition_st {
+ /* The defined type for the extension */
unsigned int type;
- int (*server_parse)(SSL *s, PACKET *pkt, int *al);
- int (*client_parse)(SSL *s, PACKET *pkt, int *al);
- int (*server_construct)(SSL *s, WPACKET *pkt, int *al);
- int (*client_construct)(SSL *s, WPACKET *pkt, int *al);
+ /*
+ * The context that this extension applies to, e.g. what messages and
+ * protocol versions
+ */
unsigned int context;
+ /*
+ * Initialise extension before parsing. Always called for relevant contexts
+ * even if extension not present
+ */
+ int (*init)(SSL *s, unsigned int context);
+ /* Parse extension sent from client to server */
+ int (*parse_ctos)(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
+ size_t chainidx, int *al);
+ /* Parse extension send from server to client */
+ int (*parse_stoc)(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
+ size_t chainidx, int *al);
+ /* Construct extension sent from server to client */
+ EXT_RETURN (*construct_stoc)(SSL *s, WPACKET *pkt, unsigned int context,
+ X509 *x, size_t chainidx, int *al);
+ /* Construct extension sent from client to server */
+ EXT_RETURN (*construct_ctos)(SSL *s, WPACKET *pkt, unsigned int context,
+ X509 *x, size_t chainidx, int *al);
+ /*
+ * Finalise extension after parsing. Always called where an extensions was
+ * initialised even if the extension was not present. |sent| is set to 1 if
+ * the extension was seen, or 0 otherwise.
+ */
+ int (*final)(SSL *s, unsigned int context, int sent, int *al);
} EXTENSION_DEFINITION;
/*
- * TODO(TLS1.3): Temporarily modified the definitions below to put all TLS1.3
- * extensions in the ServerHello for now. That needs to be put back to correct
- * setting once encrypted extensions is working properly.
+ * Definitions of all built-in extensions. NOTE: Changes in the number or order
+ * of these extensions should be mirrored with equivalent changes to the
+ * indexes ( TLSEXT_IDX_* ) defined in ssl_locl.h.
+ * Each extension has an initialiser, a client and
+ * server side parser and a finaliser. The initialiser is called (if the
+ * extension is relevant to the given context) even if we did not see the
+ * extension in the message that we received. The parser functions are only
+ * called if we see the extension in the message. The finalisers are always
+ * called if the initialiser was called.
+ * There are also server and client side constructor functions which are always
+ * called during message construction if the extension is relevant for the
+ * given context.
+ * The initialisation, parsing, finalisation and construction functions are
+ * always called in the order defined in this list. Some extensions may depend
+ * on others having been processed first, so the order of this list is
+ * significant.
+ * The extension context is defined by a series of flags which specify which
+ * messages the extension is relevant to. These flags also specify whether the
+ * extension is relevant to a particular protocol or protocol version.
+ *
+ * TODO(TLS1.3): Make sure we have a test to check the consistency of these
*/
+#define INVALID_EXTENSION { 0x10000, 0, NULL, NULL, NULL, NULL, NULL, NULL }
static const EXTENSION_DEFINITION ext_defs[] = {
{
TLSEXT_TYPE_renegotiate,
- tls_parse_clienthello_renegotiate,
- NULL,
- tls_construct_server_renegotiate,
- NULL,
- EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO | EXT_SSL3_ALLOWED
- | EXT_TLS1_2_AND_BELOW_ONLY
+ SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO
+ | SSL_EXT_SSL3_ALLOWED | SSL_EXT_TLS1_2_AND_BELOW_ONLY,
+ NULL, tls_parse_ctos_renegotiate, tls_parse_stoc_renegotiate,
+ tls_construct_stoc_renegotiate, tls_construct_ctos_renegotiate,
+ final_renegotiate
},
{
TLSEXT_TYPE_server_name,
- tls_parse_clienthello_server_name,
- NULL,
- tls_construct_server_server_name,
- NULL,
- EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO
- | /*EXT_TLS1_3_ENCRYPTED_EXTENSIONS*/EXT_TLS1_3_SERVER_HELLO
+ SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO
+ | SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS,
+ init_server_name,
+ tls_parse_ctos_server_name, tls_parse_stoc_server_name,
+ tls_construct_stoc_server_name, tls_construct_ctos_server_name,
+ final_server_name
},
#ifndef OPENSSL_NO_SRP
{
TLSEXT_TYPE_srp,
- tls_parse_clienthello_srp,
- NULL,
- NULL,
- NULL,
- EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO | EXT_TLS1_2_AND_BELOW_ONLY
+ SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_AND_BELOW_ONLY,
+ init_srp, tls_parse_ctos_srp, NULL, NULL, tls_construct_ctos_srp, NULL
},
+#else
+ INVALID_EXTENSION,
#endif
#ifndef OPENSSL_NO_EC
{
TLSEXT_TYPE_ec_point_formats,
- tls_parse_clienthello_ec_pt_formats,
- NULL,
- tls_construct_server_ec_pt_formats,
- NULL,
- EXT_CLIENT_HELLO | EXT_TLS1_2_AND_BELOW_ONLY
+ SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO
+ | SSL_EXT_TLS1_2_AND_BELOW_ONLY,
+ NULL, tls_parse_ctos_ec_pt_formats, tls_parse_stoc_ec_pt_formats,
+ tls_construct_stoc_ec_pt_formats, tls_construct_ctos_ec_pt_formats,
+ final_ec_pt_formats
},
{
TLSEXT_TYPE_supported_groups,
- tls_parse_clienthello_supported_groups,
- NULL,
- NULL /* TODO(TLS1.3): Need to add this */,
- NULL,
- EXT_CLIENT_HELLO
- | /*EXT_TLS1_3_ENCRYPTED_EXTENSIONS*/EXT_TLS1_3_SERVER_HELLO
+ SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS,
+ NULL, tls_parse_ctos_supported_groups, NULL,
+ tls_construct_stoc_supported_groups,
+ tls_construct_ctos_supported_groups, NULL
},
+#else
+ INVALID_EXTENSION,
+ INVALID_EXTENSION,
#endif
{
TLSEXT_TYPE_session_ticket,
- tls_parse_clienthello_session_ticket,
- NULL,
- tls_construct_server_session_ticket,
- NULL,
- EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO | EXT_TLS1_2_AND_BELOW_ONLY
+ SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO
+ | SSL_EXT_TLS1_2_AND_BELOW_ONLY,
+ init_session_ticket, tls_parse_ctos_session_ticket,
+ tls_parse_stoc_session_ticket, tls_construct_stoc_session_ticket,
+ tls_construct_ctos_session_ticket, NULL
},
{
TLSEXT_TYPE_signature_algorithms,
- tls_parse_clienthello_sig_algs,
- NULL,
- NULL,
- NULL,
- EXT_CLIENT_HELLO
+ SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_3_CERTIFICATE_REQUEST,
+ init_sig_algs, tls_parse_ctos_sig_algs,
+ tls_parse_ctos_sig_algs, tls_construct_ctos_sig_algs,
+ tls_construct_ctos_sig_algs, final_sig_algs
},
+#ifndef OPENSSL_NO_OCSP
{
TLSEXT_TYPE_status_request,
- tls_parse_clienthello_status_request,
- NULL,
- tls_construct_server_status_request,
- NULL,
- EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO
- | /*EXT_TLS1_3_CERTIFICATE*/EXT_TLS1_3_SERVER_HELLO
+ SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO
+ | SSL_EXT_TLS1_3_CERTIFICATE,
+ init_status_request, tls_parse_ctos_status_request,
+ tls_parse_stoc_status_request, tls_construct_stoc_status_request,
+ tls_construct_ctos_status_request, NULL
},
+#else
+ INVALID_EXTENSION,
+#endif
#ifndef OPENSSL_NO_NEXTPROTONEG
{
TLSEXT_TYPE_next_proto_neg,
- tls_parse_clienthello_npn,
- NULL,
- tls_construct_server_next_proto_neg,
- NULL,
- EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO | EXT_TLS1_2_AND_BELOW_ONLY
+ SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO
+ | SSL_EXT_TLS1_2_AND_BELOW_ONLY,
+ init_npn, tls_parse_ctos_npn, tls_parse_stoc_npn,
+ tls_construct_stoc_next_proto_neg, tls_construct_ctos_npn, NULL
},
+#else
+ INVALID_EXTENSION,
#endif
{
+ /*
+ * Must appear in this list after server_name so that finalisation
+ * happens after server_name callbacks
+ */
TLSEXT_TYPE_application_layer_protocol_negotiation,
- tls_parse_clienthello_alpn,
- NULL,
- tls_construct_server_alpn,
- NULL,
- EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO
- | /*EXT_TLS1_3_ENCRYPTED_EXTENSIONS*/EXT_TLS1_3_SERVER_HELLO
+ SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO
+ | SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS,
+ init_alpn, tls_parse_ctos_alpn, tls_parse_stoc_alpn,
+ tls_construct_stoc_alpn, tls_construct_ctos_alpn, final_alpn
},
#ifndef OPENSSL_NO_SRTP
{
TLSEXT_TYPE_use_srtp,
- tls_parse_clienthello_use_srtp,
- NULL,
- tls_construct_server_use_srtp,
- NULL,
- EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO
- | EXT_TLS1_3_ENCRYPTED_EXTENSIONS | EXT_DTLS_ONLY
+ SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO
+ | SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS | SSL_EXT_DTLS_ONLY,
+ init_srtp, tls_parse_ctos_use_srtp, tls_parse_stoc_use_srtp,
+ tls_construct_stoc_use_srtp, tls_construct_ctos_use_srtp, NULL
},
+#else
+ INVALID_EXTENSION,
#endif
{
TLSEXT_TYPE_encrypt_then_mac,
- tls_parse_clienthello_etm,
- NULL,
- tls_construct_server_etm,
- NULL,
- EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO | EXT_TLS1_2_AND_BELOW_ONLY
+ SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO
+ | SSL_EXT_TLS1_2_AND_BELOW_ONLY,
+ init_etm, tls_parse_ctos_etm, tls_parse_stoc_etm,
+ tls_construct_stoc_etm, tls_construct_ctos_etm, NULL
},
+#ifndef OPENSSL_NO_CT
{
TLSEXT_TYPE_signed_certificate_timestamp,
+ SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO
+ | SSL_EXT_TLS1_3_CERTIFICATE,
+ 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
* cannot override built in ones.
*/
- NULL,
- NULL,
- NULL,
- NULL,
- EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO
- | /*EXT_TLS1_3_CERTIFICATE*/EXT_TLS1_3_SERVER_HELLO
+ NULL, tls_parse_stoc_sct, NULL, tls_construct_ctos_sct, NULL
},
+#else
+ INVALID_EXTENSION,
+#endif
{
TLSEXT_TYPE_extended_master_secret,
- tls_parse_clienthello_ems,
- NULL,
- tls_construct_server_ems,
- NULL,
- EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO | EXT_TLS1_2_AND_BELOW_ONLY
+ SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO
+ | SSL_EXT_TLS1_2_AND_BELOW_ONLY,
+ init_ems, tls_parse_ctos_ems, tls_parse_stoc_ems,
+ tls_construct_stoc_ems, tls_construct_ctos_ems, final_ems
},
{
TLSEXT_TYPE_supported_versions,
- /* Processed inline as part of version selection */
- NULL,
- NULL,
- NULL,
+ SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS_IMPLEMENTATION_ONLY
+ | SSL_EXT_TLS1_3_ONLY,
NULL,
- EXT_CLIENT_HELLO | EXT_TLS_IMPLEMENTATION_ONLY
+ /* Processed inline as part of version selection */
+ NULL, NULL, NULL, tls_construct_ctos_supported_versions, NULL
},
{
- TLSEXT_TYPE_padding,
- /* We send this, but don't read it */
- NULL,
- NULL,
- NULL,
- NULL,
- EXT_CLIENT_HELLO
+ TLSEXT_TYPE_psk_kex_modes,
+ SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS_IMPLEMENTATION_ONLY
+ | SSL_EXT_TLS1_3_ONLY,
+ init_psk_kex_modes, tls_parse_ctos_psk_kex_modes, NULL, NULL,
+ tls_construct_ctos_psk_kex_modes, NULL
},
+#ifndef OPENSSL_NO_EC
{
+ /*
+ * Must be in this list after supported_groups. We need that to have
+ * been parsed before we do this one.
+ */
TLSEXT_TYPE_key_share,
- tls_parse_clienthello_key_share,
- NULL,
- tls_construct_server_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
+ SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_3_SERVER_HELLO
+ | SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST | SSL_EXT_TLS_IMPLEMENTATION_ONLY
+ | SSL_EXT_TLS1_3_ONLY,
+ NULL, tls_parse_ctos_key_share, tls_parse_stoc_key_share,
+ tls_construct_stoc_key_share, tls_construct_ctos_key_share,
+ final_key_share
+ },
+#endif
+ {
+ TLSEXT_TYPE_cookie,
+ SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST
+ | SSL_EXT_TLS_IMPLEMENTATION_ONLY | SSL_EXT_TLS1_3_ONLY,
+ NULL, NULL, tls_parse_stoc_cookie, NULL, tls_construct_ctos_cookie,
+ NULL
},
{
/*
* SSL_OP_CRYPTOPRO_TLSEXT_BUG is set
*/
TLSEXT_TYPE_cryptopro_bug,
+ SSL_EXT_TLS1_2_SERVER_HELLO | SSL_EXT_TLS1_2_AND_BELOW_ONLY,
+ NULL, NULL, NULL, tls_construct_stoc_cryptopro_bug, NULL, NULL
+ },
+ {
+ TLSEXT_TYPE_early_data,
+ SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS
+ | SSL_EXT_TLS1_3_NEW_SESSION_TICKET,
+ NULL, tls_parse_ctos_early_data, tls_parse_stoc_early_data,
+ tls_construct_stoc_early_data, tls_construct_ctos_early_data,
+ final_early_data
+ },
+ {
+ TLSEXT_TYPE_certificate_authorities,
+ SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_3_CERTIFICATE_REQUEST
+ | SSL_EXT_TLS1_3_ONLY,
+ init_certificate_authorities,
+ tls_parse_certificate_authorities, tls_parse_certificate_authorities,
+ tls_construct_certificate_authorities,
+ tls_construct_certificate_authorities, NULL,
+ },
+ {
+ /* Must be immediately before pre_shared_key */
+ TLSEXT_TYPE_padding,
+ SSL_EXT_CLIENT_HELLO,
NULL,
- NULL,
- tls_construct_server_cryptopro_bug,
- NULL,
- EXT_TLS1_2_SERVER_HELLO | EXT_TLS1_2_AND_BELOW_ONLY
+ /* We send this, but don't read it */
+ NULL, NULL, NULL, tls_construct_ctos_padding, NULL
+ },
+ {
+ /* Required by the TLSv1.3 spec to always be the last extension */
+ TLSEXT_TYPE_psk,
+ SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_3_SERVER_HELLO
+ | SSL_EXT_TLS_IMPLEMENTATION_ONLY | SSL_EXT_TLS1_3_ONLY,
+ NULL, tls_parse_ctos_psk, tls_parse_stoc_psk, tls_construct_stoc_psk,
+ tls_construct_ctos_psk, NULL
}
};
-/*
- * Comparison function used in a call to qsort (see tls_collect_extensions()
- * below.)
- * The two arguments |p1| and |p2| are expected to be pointers to RAW_EXTENSIONs
- *
- * Returns:
- * 1 if the type for p1 is greater than p2
- * 0 if the type for p1 and p2 are the same
- * -1 if the type for p1 is less than p2
- */
-static int compare_extensions(const void *p1, const void *p2)
+/* Check whether an extension's context matches the current context */
+static int validate_context(SSL *s, unsigned int extctx, unsigned int thisctx)
{
- const RAW_EXTENSION *e1 = (const RAW_EXTENSION *)p1;
- const RAW_EXTENSION *e2 = (const RAW_EXTENSION *)p2;
+ /* Check we're allowed to use this extension in this context */
+ if ((thisctx & extctx) == 0)
+ return 0;
- if (e1->type < e2->type)
- return -1;
- else if (e1->type > e2->type)
- return 1;
+ if (SSL_IS_DTLS(s)) {
+ if ((extctx & SSL_EXT_TLS_ONLY) != 0)
+ return 0;
+ } else if ((extctx & SSL_EXT_DTLS_ONLY) != 0) {
+ return 0;
+ }
- return 0;
+ return 1;
}
/*
* Verify whether we are allowed to use the extension |type| in the current
* |context|. Returns 1 to indicate the extension is allowed or unknown or 0 to
- * indicate the extension is not allowed.
+ * indicate the extension is not allowed. If returning 1 then |*found| is set to
+ * the definition for the extension we found.
*/
-static int verify_extension(SSL *s, unsigned int context, unsigned int type)
+static int verify_extension(SSL *s, unsigned int context, unsigned int type,
+ custom_ext_methods *meths, RAW_EXTENSION *rawexlist,
+ RAW_EXTENSION **found)
{
size_t i;
+ size_t builtin_num = OSSL_NELEM(ext_defs);
+ const EXTENSION_DEFINITION *thisext;
- for (i = 0; i < OSSL_NELEM(ext_defs); i++) {
- if (type == ext_defs[i].type) {
- /* Check we're allowed to use this extension in this context */
- if ((context & ext_defs[i].context) == 0)
+ for (i = 0, thisext = ext_defs; i < builtin_num; i++, thisext++) {
+ if (type == thisext->type) {
+ if (!validate_context(s, thisext->context, context))
return 0;
- if (SSL_IS_DTLS(s)) {
- if ((ext_defs[i].context & EXT_TLS_ONLY) != 0)
- return 0;
- } else if ((ext_defs[i].context & EXT_DTLS_ONLY) != 0) {
- return 0;
- }
+ *found = &rawexlist[i];
+ return 1;
+ }
+ }
+
+ /* Check the custom extensions */
+ if (meths != NULL) {
+ size_t offset = 0;
+ ENDPOINT role = ENDPOINT_BOTH;
+ custom_ext_method *meth = NULL;
+ if ((context & SSL_EXT_CLIENT_HELLO) != 0)
+ role = ENDPOINT_SERVER;
+ else if ((context & SSL_EXT_TLS1_2_SERVER_HELLO) != 0)
+ role = ENDPOINT_CLIENT;
+
+ meth = custom_ext_find(meths, role, type, &offset);
+ if (meth != NULL) {
+ if (!validate_context(s, meth->context, context))
+ return 0;
+ *found = &rawexlist[offset + builtin_num];
return 1;
}
}
/* Unknown extension. We allow it */
+ *found = NULL;
return 1;
}
/*
- * Finds an extension definition for the give extension |type|.
- * Returns 1 if found and stores the definition in |*def|, or returns 0
- * otherwise.
+ * Check whether the context defined for an extension |extctx| means whether
+ * the extension is relevant for the current context |thisctx| or not. Returns
+ * 1 if the extension is relevant for this context, and 0 otherwise
*/
-static int find_extension_definition(SSL *s, unsigned int type,
- const EXTENSION_DEFINITION **def)
+int extension_is_relevant(SSL *s, unsigned int extctx, unsigned int thisctx)
{
- size_t i;
-
- for (i = 0; i < OSSL_NELEM(ext_defs); i++) {
- if (type == ext_defs[i].type) {
- *def = &ext_defs[i];
- return 1;
- }
- }
+ if ((SSL_IS_DTLS(s)
+ && (extctx & SSL_EXT_TLS_IMPLEMENTATION_ONLY) != 0)
+ || (s->version == SSL3_VERSION
+ && (extctx & SSL_EXT_SSL3_ALLOWED) == 0)
+ || (SSL_IS_TLS13(s)
+ && (extctx & SSL_EXT_TLS1_2_AND_BELOW_ONLY) != 0)
+ || (!SSL_IS_TLS13(s) && (extctx & SSL_EXT_TLS1_3_ONLY) != 0)
+ || (s->hit && (extctx & SSL_EXT_IGNORE_ON_RESUMPTION) != 0))
+ return 0;
- /* Unknown extension */
- return 0;
+ return 1;
}
/*
* Gather a list of all the extensions from the data in |packet]. |context|
* tells us which message this extension is for. The raw extension data is
- * stored in |*res| with the number of found extensions in |*numfound|. In the
- * event of an error the alert type to use is stored in |*ad|. We don't actually
- * process the content of the extensions yet, except to check their types.
+ * stored in |*res| on success. In the event of an error the alert type to use
+ * is stored in |*al|. We don't actually process the content of the extensions
+ * yet, except to check their types. This function also runs the initialiser
+ * functions for all known extensions if |init| is nonzero (whether we have
+ * collected them or not). If successful the caller is responsible for freeing
+ * the contents of |*res|.
*
* Per http://tools.ietf.org/html/rfc5246#section-7.4.1.4, there may not be
* more than one extension of the same type in a ClientHello or ServerHello.
* This function returns 1 if all extensions are unique and we have parsed their
* types, and 0 if the extensions contain duplicates, could not be successfully
- * parsed, or an internal error occurred.
- */
-/*
- * TODO(TLS1.3): Refactor ServerHello extension parsing to use this and then
- * remove tls1_check_duplicate_extensions()
+ * found, or an internal error occurred. We only check duplicates for
+ * extensions that we know about. We ignore others.
*/
int tls_collect_extensions(SSL *s, PACKET *packet, unsigned int context,
- RAW_EXTENSION **res, size_t *numfound, int *ad)
+ RAW_EXTENSION **res, int *al, size_t *len,
+ int init)
{
PACKET extensions = *packet;
- size_t num_extensions = 0, i = 0;
+ size_t i = 0;
+ size_t num_exts;
+ custom_ext_methods *exts = &s->cert->custext;
RAW_EXTENSION *raw_extensions = NULL;
+ const EXTENSION_DEFINITION *thisexd;
+
+ *res = NULL;
+
+ /*
+ * Initialise server side custom extensions. Client side is done during
+ * construction of extensions for the ClientHello.
+ */
+ if ((context & SSL_EXT_CLIENT_HELLO) != 0)
+ custom_ext_init(&s->cert->custext);
+
+ num_exts = OSSL_NELEM(ext_defs) + (exts != NULL ? exts->meths_count : 0);
+ raw_extensions = OPENSSL_zalloc(num_exts * sizeof(*raw_extensions));
+ if (raw_extensions == NULL) {
+ *al = SSL_AD_INTERNAL_ERROR;
+ SSLerr(SSL_F_TLS_COLLECT_EXTENSIONS, ERR_R_MALLOC_FAILURE);
+ return 0;
+ }
- /* First pass: count the extensions. */
while (PACKET_remaining(&extensions) > 0) {
- unsigned int type;
+ unsigned int type, idx;
PACKET extension;
+ RAW_EXTENSION *thisex;
if (!PACKET_get_net_2(&extensions, &type) ||
!PACKET_get_length_prefixed_2(&extensions, &extension)) {
SSLerr(SSL_F_TLS_COLLECT_EXTENSIONS, SSL_R_BAD_EXTENSION);
- *ad = SSL_AD_DECODE_ERROR;
+ *al = SSL_AD_DECODE_ERROR;
goto err;
}
- /* Verify this extension is allowed */
- if (!verify_extension(s, context, type)) {
+ /*
+ * Verify this extension is allowed. We only check duplicates for
+ * extensions that we recognise. We also have a special case for the
+ * PSK extension, which must be the last one in the ClientHello.
+ */
+ if (!verify_extension(s, context, type, exts, raw_extensions, &thisex)
+ || (thisex != NULL && thisex->present == 1)
+ || (type == TLSEXT_TYPE_psk
+ && (context & SSL_EXT_CLIENT_HELLO) != 0
+ && PACKET_remaining(&extensions) != 0)) {
SSLerr(SSL_F_TLS_COLLECT_EXTENSIONS, SSL_R_BAD_EXTENSION);
- *ad = SSL_AD_ILLEGAL_PARAMETER;
+ *al = SSL_AD_ILLEGAL_PARAMETER;
goto err;
}
- num_extensions++;
- }
-
- if (num_extensions > 0) {
- raw_extensions = OPENSSL_zalloc(sizeof(*raw_extensions)
- * num_extensions);
- if (raw_extensions == NULL) {
- *ad = SSL_AD_INTERNAL_ERROR;
- SSLerr(SSL_F_TLS_COLLECT_EXTENSIONS, ERR_R_MALLOC_FAILURE);
+ idx = thisex - raw_extensions;
+ /*-
+ * Check that we requested this extension (if appropriate). Requests can
+ * be sent in the ClientHello and CertificateRequest. Unsolicited
+ * extensions can be sent in the NewSessionTicket. We only do this for
+ * the built-in extensions. Custom extensions have a different but
+ * similar check elsewhere.
+ * Special cases:
+ * - The HRR cookie extension is unsolicited
+ * - The renegotiate extension is unsolicited (the client signals
+ * support via an SCSV)
+ * - The signed_certificate_timestamp extension can be provided by a
+ * custom extension or by the built-in version. We let the extension
+ * itself handle unsolicited response checks.
+ */
+ if (idx < OSSL_NELEM(ext_defs)
+ && (context & (SSL_EXT_CLIENT_HELLO
+ | SSL_EXT_TLS1_3_CERTIFICATE_REQUEST
+ | SSL_EXT_TLS1_3_NEW_SESSION_TICKET)) == 0
+ && type != TLSEXT_TYPE_cookie
+ && type != TLSEXT_TYPE_renegotiate
+ && type != TLSEXT_TYPE_signed_certificate_timestamp
+ && (s->ext.extflags[idx] & SSL_EXT_FLAG_SENT) == 0) {
+ SSLerr(SSL_F_TLS_COLLECT_EXTENSIONS, SSL_R_UNSOLICITED_EXTENSION);
+ *al = SSL_AD_UNSUPPORTED_EXTENSION;
goto err;
}
-
- /* Second pass: collect the extensions. */
- for (i = 0; i < num_extensions; i++) {
- if (!PACKET_get_net_2(packet, &raw_extensions[i].type) ||
- !PACKET_get_length_prefixed_2(packet,
- &raw_extensions[i].data)) {
- /* This should not happen. */
- *ad = SSL_AD_INTERNAL_ERROR;
- SSLerr(SSL_F_TLS_COLLECT_EXTENSIONS, ERR_R_INTERNAL_ERROR);
- goto err;
- }
+ if (thisex != NULL) {
+ thisex->data = extension;
+ thisex->present = 1;
+ thisex->type = type;
}
+ }
- if (PACKET_remaining(packet) != 0) {
- *ad = SSL_AD_DECODE_ERROR;
- SSLerr(SSL_F_TLS_COLLECT_EXTENSIONS, SSL_R_LENGTH_MISMATCH);
- goto err;
- }
- /* Sort the extensions and make sure there are no duplicates. */
- qsort(raw_extensions, num_extensions, sizeof(*raw_extensions),
- compare_extensions);
- for (i = 1; i < num_extensions; i++) {
- if (raw_extensions[i - 1].type == raw_extensions[i].type) {
- *ad = SSL_AD_DECODE_ERROR;
+ if (init) {
+ /*
+ * Initialise all known extensions relevant to this context,
+ * whether we have found them or not
+ */
+ for (thisexd = ext_defs, i = 0; i < OSSL_NELEM(ext_defs);
+ i++, thisexd++) {
+ if (thisexd->init != NULL && (thisexd->context & context) != 0
+ && extension_is_relevant(s, thisexd->context, context)
+ && !thisexd->init(s, context)) {
+ *al = SSL_AD_INTERNAL_ERROR;
goto err;
}
}
}
*res = raw_extensions;
- *numfound = num_extensions;
+ if (len != NULL)
+ *len = num_exts;
return 1;
err:
return 0;
}
-int tls_parse_all_extensions(SSL *s, int context, RAW_EXTENSION *exts,
- size_t numexts, int *al)
+/*
+ * Runs the parser for a given extension with index |idx|. |exts| contains the
+ * list of all parsed extensions previously collected by
+ * tls_collect_extensions(). The parser is only run if it is applicable for the
+ * given |context| and the parser has not already been run. If this is for a
+ * Certificate message, then we also provide the parser with the relevant
+ * Certificate |x| and its position in the |chainidx| with 0 being the first
+ * Certificate. Returns 1 on success or 0 on failure. In the event of a failure
+ * |*al| is populated with a suitable alert code. If an extension is not present
+ * this counted as success.
+ */
+int tls_parse_extension(SSL *s, TLSEXT_INDEX idx, int context,
+ RAW_EXTENSION *exts, X509 *x, size_t chainidx, int *al)
{
- size_t loop;
+ RAW_EXTENSION *currext = &exts[idx];
+ int (*parser)(SSL *s, PACKET *pkt, unsigned int context, X509 *x,
+ size_t chainidx, int *al) = NULL;
- for (loop = 0; loop < numexts; loop++) {
- RAW_EXTENSION *currext = &exts[loop];
- const EXTENSION_DEFINITION *extdef = NULL;
- int (*parser)(SSL *s, PACKET *pkt, int *al) = NULL;
+ /* Skip if the extension is not present */
+ if (!currext->present)
+ return 1;
- if (s->tlsext_debug_cb)
- s->tlsext_debug_cb(s, 0, currext->type,
- PACKET_data(&currext->data),
- PACKET_remaining(&currext->data),
- s->tlsext_debug_arg);
+ if (s->ext.debug_cb)
+ s->ext.debug_cb(s, !s->server, currext->type,
+ PACKET_data(&currext->data),
+ PACKET_remaining(&currext->data),
+ s->ext.debug_arg);
- /* Skip if we've already parsed this extension */
- if (currext->parsed)
- continue;
+ /* Skip if we've already parsed this extension */
+ if (currext->parsed)
+ return 1;
- currext->parsed = 1;
-
- parser = NULL;
- if (find_extension_definition(s, currext->type, &extdef)) {
- parser = s->server ? extdef->server_parse : extdef->client_parse;
-
- /* Check if extension is defined for our protocol. If not, skip */
- if ((SSL_IS_DTLS(s)
- && (extdef->context & EXT_TLS_IMPLEMENTATION_ONLY) != 0)
- || (s->version == SSL3_VERSION
- && (extdef->context & EXT_SSL3_ALLOWED) == 0)
- || (SSL_IS_TLS13(s)
- && (extdef->context & EXT_TLS1_2_AND_BELOW_ONLY) != 0)
- || (!SSL_IS_TLS13(s)
- && (extdef->context & EXT_TLS1_3_ONLY) != 0))
- continue;
- }
+ currext->parsed = 1;
- if (parser == NULL) {
- /*
- * Could be a custom extension. We only allow this if it is a non
- * resumed session on the server side.
- *
- * TODO(TLS1.3): We only allow old style <=TLS1.2 custom extensions.
- * We're going to need a new mechanism for TLS1.3 to specify which
- * messages to add the custom extensions to.
- */
- if ((!s->hit || !s->server)
- && (context
- & (EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO)) != 0
- && custom_ext_parse(s, s->server, currext->type,
- PACKET_data(&currext->data),
- PACKET_remaining(&currext->data),
- al) <= 0)
- return 0;
+ if (idx < OSSL_NELEM(ext_defs)) {
+ /* We are handling a built-in extension */
+ const EXTENSION_DEFINITION *extdef = &ext_defs[idx];
- continue;
- }
+ /* Check if extension is defined for our protocol. If not, skip */
+ if (!extension_is_relevant(s, extdef->context, context))
+ return 1;
- if (!parser(s, &currext->data, al))
- return 0;
+ parser = s->server ? extdef->parse_ctos : extdef->parse_stoc;
+
+ if (parser != NULL)
+ return parser(s, &currext->data, context, x, chainidx, al);
+
+ /*
+ * If the parser is NULL we fall through to the custom extension
+ * processing
+ */
}
+ /* Parse custom extensions */
+ if (custom_ext_parse(s, context, currext->type,
+ PACKET_data(&currext->data),
+ PACKET_remaining(&currext->data),
+ x, chainidx, al) <= 0)
+ return 0;
+
return 1;
}
/*
- * Find a specific extension by |type| in the list |exts| containing |numexts|
- * extensions, and the parse it immediately. Returns 1 on success, or 0 on
- * failure. If a failure has occurred then |*al| will also be set to the alert
- * to be sent.
+ * Parse all remaining extensions that have not yet been parsed. Also calls the
+ * finalisation for all extensions at the end if |fin| is nonzero, whether we
+ * collected them or not. Returns 1 for success or 0 for failure. If we are
+ * working on a Certificate message then we also pass the Certificate |x| and
+ * its position in the |chainidx|, with 0 being the first certificate. On
+ * failure, |*al| is populated with a suitable alert code.
*/
-int tls_parse_extension(SSL *s, int type, int context, RAW_EXTENSION *exts,
- size_t numexts, int *al)
+int tls_parse_all_extensions(SSL *s, int context, RAW_EXTENSION *exts, X509 *x,
+ size_t chainidx, int *al, int fin)
{
- RAW_EXTENSION *ext = tls_get_extension_by_type(exts, numexts, type);
+ size_t i, numexts = OSSL_NELEM(ext_defs);
+ const EXTENSION_DEFINITION *thisexd;
- if (ext == NULL)
- return 1;
+ /* Calculate the number of extensions in the extensions list */
+ numexts += s->cert->custext.meths_count;
+
+ /* Parse each extension in turn */
+ for (i = 0; i < numexts; i++) {
+ if (!tls_parse_extension(s, i, context, exts, x, chainidx, al))
+ return 0;
+ }
+
+ if (fin) {
+ /*
+ * Finalise all known extensions relevant to this context,
+ * whether we have found them or not
+ */
+ for (i = 0, thisexd = ext_defs; i < OSSL_NELEM(ext_defs);
+ i++, thisexd++) {
+ if (thisexd->final != NULL && (thisexd->context & context) != 0
+ && !thisexd->final(s, context, exts[i].present, al))
+ return 0;
+ }
+ }
- return tls_parse_all_extensions(s, context, ext, 1, al);
+ return 1;
}
+int should_add_extension(SSL *s, unsigned int extctx, unsigned int thisctx,
+ int max_version)
+{
+ /* Skip if not relevant for our context */
+ if ((extctx & thisctx) == 0)
+ return 0;
+
+ /* Check if this extension is defined for our protocol. If not, skip */
+ if ((SSL_IS_DTLS(s) && (extctx & SSL_EXT_TLS_IMPLEMENTATION_ONLY) != 0)
+ || (s->version == SSL3_VERSION
+ && (extctx & SSL_EXT_SSL3_ALLOWED) == 0)
+ || (SSL_IS_TLS13(s)
+ && (extctx & SSL_EXT_TLS1_2_AND_BELOW_ONLY) != 0)
+ || (!SSL_IS_TLS13(s)
+ && (extctx & SSL_EXT_TLS1_3_ONLY) != 0
+ && (thisctx & SSL_EXT_CLIENT_HELLO) == 0)
+ || ((extctx & SSL_EXT_TLS1_3_ONLY) != 0
+ && (thisctx & SSL_EXT_CLIENT_HELLO) != 0
+ && (SSL_IS_DTLS(s) || max_version < TLS1_3_VERSION)))
+ return 0;
+
+ return 1;
+}
+
+/*
+ * Construct all the extensions relevant to the current |context| and write
+ * them to |pkt|. If this is an extension for a Certificate in a Certificate
+ * message, then |x| will be set to the Certificate we are handling, and
+ * |chainidx| will indicate the position in the chainidx we are processing (with
+ * 0 being the first in the chain). Returns 1 on success or 0 on failure. If a
+ * failure occurs then |al| is populated with a suitable alert code. On a
+ * failure construction stops at the first extension to fail to construct.
+ */
int tls_construct_extensions(SSL *s, WPACKET *pkt, unsigned int context,
- int *al)
+ X509 *x, size_t chainidx, int *al)
{
- size_t loop;
- int addcustom = 0;
+ size_t i;
+ int min_version, max_version = 0, reason, tmpal;
+ const EXTENSION_DEFINITION *thisexd;
/*
- * Normally if something goes wrong during construction its an internal
+ * Normally if something goes wrong during construction it's an internal
* error. We can always override this later.
*/
- *al = SSL_AD_INTERNAL_ERROR;
+ tmpal = SSL_AD_INTERNAL_ERROR;
if (!WPACKET_start_sub_packet_u16(pkt)
/*
* If extensions are of zero length then we don't even add the
* extensions length bytes to a ClientHello/ServerHello in SSLv3
*/
- || ((context & (EXT_CLIENT_HELLO | EXT_TLS1_2_SERVER_HELLO)) != 0
- && s->version == SSL3_VERSION
- && !WPACKET_set_flags(pkt,
+ || ((context &
+ (SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO)) != 0
+ && s->version == SSL3_VERSION
+ && !WPACKET_set_flags(pkt,
WPACKET_FLAGS_ABANDON_ON_ZERO_LENGTH))) {
SSLerr(SSL_F_TLS_CONSTRUCT_EXTENSIONS, ERR_R_INTERNAL_ERROR);
- return 0;
+ goto err;
+ }
+
+ if ((context & SSL_EXT_CLIENT_HELLO) != 0) {
+ reason = ssl_get_min_max_version(s, &min_version, &max_version);
+ if (reason != 0) {
+ SSLerr(SSL_F_TLS_CONSTRUCT_EXTENSIONS, reason);
+ goto err;
+ }
+ }
+
+ /* Add custom extensions first */
+ if ((context & SSL_EXT_CLIENT_HELLO) != 0) {
+ /* On the server side with initiase during ClientHello parsing */
+ custom_ext_init(&s->cert->custext);
+ }
+ if (!custom_ext_add(s, context, pkt, x, chainidx, max_version, &tmpal)) {
+ SSLerr(SSL_F_TLS_CONSTRUCT_EXTENSIONS, ERR_R_INTERNAL_ERROR);
+ goto err;
}
- for (loop = 0; loop < OSSL_NELEM(ext_defs); loop++) {
- int (*construct)(SSL *s, WPACKET *pkt, int *al);
+ for (i = 0, thisexd = ext_defs; i < OSSL_NELEM(ext_defs); i++, thisexd++) {
+ EXT_RETURN (*construct)(SSL *s, WPACKET *pkt, unsigned int context,
+ X509 *x, size_t chainidx, int *al);
+ EXT_RETURN ret;
/* Skip if not relevant for our context */
- if ((ext_defs[loop].context & context) == 0)
+ if (!should_add_extension(s, thisexd->context, context, max_version))
continue;
- construct = s->server ? ext_defs[loop].server_construct
- : ext_defs[loop].client_construct;
-
- /* Check if this extension is defined for our protocol. If not, skip */
- if ((SSL_IS_DTLS(s)
- && (ext_defs[loop].context & EXT_TLS_IMPLEMENTATION_ONLY)
- != 0)
- || (s->version == SSL3_VERSION
- && (ext_defs[loop].context & EXT_SSL3_ALLOWED) == 0)
- || (SSL_IS_TLS13(s)
- && (ext_defs[loop].context & EXT_TLS1_2_AND_BELOW_ONLY)
- != 0)
- || (!SSL_IS_TLS13(s)
- && (ext_defs[loop].context & EXT_TLS1_3_ONLY) != 0
- && (context & EXT_CLIENT_HELLO) == 0)
- || construct == NULL)
+ construct = s->server ? thisexd->construct_stoc
+ : thisexd->construct_ctos;
+
+ if (construct == NULL)
continue;
- if (!construct(s, pkt, al))
+ ret = construct(s, pkt, context, x, chainidx, &tmpal);
+ if (ret == EXT_RETURN_FAIL)
+ goto err;
+ if (ret == EXT_RETURN_SENT
+ && (context & (SSL_EXT_CLIENT_HELLO
+ | SSL_EXT_TLS1_3_CERTIFICATE_REQUEST
+ | SSL_EXT_TLS1_3_NEW_SESSION_TICKET)) != 0)
+ s->ext.extflags[i] |= SSL_EXT_FLAG_SENT;
+ }
+
+ if (!WPACKET_close(pkt)) {
+ SSLerr(SSL_F_TLS_CONSTRUCT_EXTENSIONS, ERR_R_INTERNAL_ERROR);
+ goto err;
+ }
+
+ return 1;
+
+ err:
+ *al = tmpal;
+ return 0;
+}
+
+/*
+ * Built in extension finalisation and initialisation functions. All initialise
+ * or finalise the associated extension type for the given |context|. For
+ * finalisers |sent| is set to 1 if we saw the extension during parsing, and 0
+ * otherwise. These functions return 1 on success or 0 on failure. In the event
+ * of a failure then |*al| is populated with a suitable error code.
+ */
+
+static int final_renegotiate(SSL *s, unsigned int context, int sent,
+ int *al)
+{
+ if (!s->server) {
+ /*
+ * Check if we can connect to a server that doesn't support safe
+ * renegotiation
+ */
+ if (!(s->options & SSL_OP_LEGACY_SERVER_CONNECT)
+ && !(s->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION)
+ && !sent) {
+ *al = SSL_AD_HANDSHAKE_FAILURE;
+ SSLerr(SSL_F_FINAL_RENEGOTIATE,
+ SSL_R_UNSAFE_LEGACY_RENEGOTIATION_DISABLED);
return 0;
+ }
+
+ return 1;
}
- /* Add custom extensions */
- if ((context & EXT_CLIENT_HELLO) != 0) {
- custom_ext_init(&s->cert->cli_ext);
- addcustom = 1;
- } else if ((context & EXT_TLS1_2_SERVER_HELLO) != 0) {
+ /* Need RI if renegotiating */
+ if (s->renegotiate
+ && !(s->options & SSL_OP_ALLOW_UNSAFE_LEGACY_RENEGOTIATION)
+ && !sent) {
+ *al = SSL_AD_HANDSHAKE_FAILURE;
+ SSLerr(SSL_F_FINAL_RENEGOTIATE,
+ SSL_R_UNSAFE_LEGACY_RENEGOTIATION_DISABLED);
+ return 0;
+ }
+
+
+ return 1;
+}
+
+static int init_server_name(SSL *s, unsigned int context)
+{
+ if (s->server)
+ s->servername_done = 0;
+
+ return 1;
+}
+
+static int final_server_name(SSL *s, unsigned int context, int sent,
+ int *al)
+{
+ int ret = SSL_TLSEXT_ERR_NOACK;
+ int altmp = SSL_AD_UNRECOGNIZED_NAME;
+
+ if (s->ctx != NULL && s->ctx->ext.servername_cb != 0)
+ ret = s->ctx->ext.servername_cb(s, &altmp,
+ s->ctx->ext.servername_arg);
+ else if (s->session_ctx != NULL
+ && s->session_ctx->ext.servername_cb != 0)
+ ret = s->session_ctx->ext.servername_cb(s, &altmp,
+ s->session_ctx->ext.servername_arg);
+
+ switch (ret) {
+ case SSL_TLSEXT_ERR_ALERT_FATAL:
+ *al = altmp;
+ return 0;
+
+ case SSL_TLSEXT_ERR_ALERT_WARNING:
+ *al = altmp;
+ return 1;
+
+ case SSL_TLSEXT_ERR_NOACK:
+ s->servername_done = 0;
+ return 1;
+
+ default:
+ return 1;
+ }
+}
+
+#ifndef OPENSSL_NO_EC
+static int final_ec_pt_formats(SSL *s, unsigned int context, int sent,
+ int *al)
+{
+ unsigned long alg_k, alg_a;
+
+ if (s->server)
+ return 1;
+
+ alg_k = s->s3->tmp.new_cipher->algorithm_mkey;
+ alg_a = s->s3->tmp.new_cipher->algorithm_auth;
+
+ /*
+ * If we are client and using an elliptic curve cryptography cipher
+ * suite, then if server returns an EC point formats lists extension it
+ * must contain uncompressed.
+ */
+ if (s->ext.ecpointformats != NULL
+ && s->ext.ecpointformats_len > 0
+ && s->session->ext.ecpointformats != NULL
+ && s->session->ext.ecpointformats_len > 0
+ && ((alg_k & SSL_kECDHE) || (alg_a & SSL_aECDSA))) {
+ /* we are using an ECC cipher */
+ size_t i;
+ unsigned char *list = s->session->ext.ecpointformats;
+
+ for (i = 0; i < s->session->ext.ecpointformats_len; i++) {
+ if (*list++ == TLSEXT_ECPOINTFORMAT_uncompressed)
+ break;
+ }
+ if (i == s->session->ext.ecpointformats_len) {
+ SSLerr(SSL_F_FINAL_EC_PT_FORMATS,
+ SSL_R_TLS_INVALID_ECPOINTFORMAT_LIST);
+ return 0;
+ }
+ }
+
+ return 1;
+}
+#endif
+
+static int init_session_ticket(SSL *s, unsigned int context)
+{
+ if (!s->server)
+ s->ext.ticket_expected = 0;
+
+ return 1;
+}
+
+#ifndef OPENSSL_NO_OCSP
+static int init_status_request(SSL *s, unsigned int context)
+{
+ if (s->server) {
+ s->ext.status_type = TLSEXT_STATUSTYPE_nothing;
+ } else {
/*
- * We already initialised the custom extensions during ClientHello
- * parsing.
- *
- * TODO(TLS1.3): We're going to need a new custom extension mechanism
- * for TLS1.3, so that custom extensions can specify which of the
- * multiple message they wish to add themselves to.
+ * Ensure we get sensible values passed to tlsext_status_cb in the event
+ * that we don't receive a status message
*/
- addcustom = 1;
+ OPENSSL_free(s->ext.ocsp.resp);
+ s->ext.ocsp.resp = NULL;
+ s->ext.ocsp.resp_len = 0;
}
- if (addcustom && !custom_ext_add(s, s->server, pkt, al)) {
- SSLerr(SSL_F_TLS_CONSTRUCT_EXTENSIONS, ERR_R_INTERNAL_ERROR);
+ return 1;
+}
+#endif
+
+#ifndef OPENSSL_NO_NEXTPROTONEG
+static int init_npn(SSL *s, unsigned int context)
+{
+ s->s3->npn_seen = 0;
+
+ return 1;
+}
+#endif
+
+static int init_alpn(SSL *s, unsigned int context)
+{
+ OPENSSL_free(s->s3->alpn_selected);
+ s->s3->alpn_selected = NULL;
+ s->s3->alpn_selected_len = 0;
+ if (s->server) {
+ OPENSSL_free(s->s3->alpn_proposed);
+ s->s3->alpn_proposed = NULL;
+ s->s3->alpn_proposed_len = 0;
+ }
+ return 1;
+}
+
+static int final_alpn(SSL *s, unsigned int context, int sent, int *al)
+{
+ const unsigned char *selected = NULL;
+ unsigned char selected_len = 0;
+
+ if (!s->server)
+ return 1;
+
+ if (s->ctx->ext.alpn_select_cb != NULL && s->s3->alpn_proposed != NULL) {
+ int r = s->ctx->ext.alpn_select_cb(s, &selected, &selected_len,
+ s->s3->alpn_proposed,
+ (unsigned int)s->s3->alpn_proposed_len,
+ s->ctx->ext.alpn_select_cb_arg);
+
+ if (r == SSL_TLSEXT_ERR_OK) {
+ OPENSSL_free(s->s3->alpn_selected);
+ s->s3->alpn_selected = OPENSSL_memdup(selected, selected_len);
+ if (s->s3->alpn_selected == NULL) {
+ *al = SSL_AD_INTERNAL_ERROR;
+ return 0;
+ }
+ s->s3->alpn_selected_len = selected_len;
+#ifndef OPENSSL_NO_NEXTPROTONEG
+ /* ALPN takes precedence over NPN. */
+ s->s3->npn_seen = 0;
+#endif
+ } else if (r == SSL_TLSEXT_ERR_NOACK) {
+ /* Behave as if no callback was present. */
+ return 1;
+ } else {
+ *al = SSL_AD_NO_APPLICATION_PROTOCOL;
+ return 0;
+ }
+ }
+
+ return 1;
+}
+
+static int init_sig_algs(SSL *s, unsigned int context)
+{
+ /* Clear any signature algorithms extension received */
+ OPENSSL_free(s->s3->tmp.peer_sigalgs);
+ s->s3->tmp.peer_sigalgs = NULL;
+
+ return 1;
+}
+
+#ifndef OPENSSL_NO_SRP
+static int init_srp(SSL *s, unsigned int context)
+{
+ OPENSSL_free(s->srp_ctx.login);
+ s->srp_ctx.login = NULL;
+
+ return 1;
+}
+#endif
+
+static int init_etm(SSL *s, unsigned int context)
+{
+ s->ext.use_etm = 0;
+
+ return 1;
+}
+
+static int init_ems(SSL *s, unsigned int context)
+{
+ if (!s->server)
+ s->s3->flags &= ~TLS1_FLAGS_RECEIVED_EXTMS;
+
+ return 1;
+}
+
+static int final_ems(SSL *s, unsigned int context, int sent, int *al)
+{
+ if (!s->server && s->hit) {
+ /*
+ * Check extended master secret extension is consistent with
+ * original session.
+ */
+ if (!(s->s3->flags & TLS1_FLAGS_RECEIVED_EXTMS) !=
+ !(s->session->flags & SSL_SESS_FLAG_EXTMS)) {
+ *al = SSL_AD_HANDSHAKE_FAILURE;
+ SSLerr(SSL_F_FINAL_EMS, SSL_R_INCONSISTENT_EXTMS);
+ return 0;
+ }
+ }
+
+ return 1;
+}
+
+static int init_certificate_authorities(SSL *s, unsigned int context)
+{
+ sk_X509_NAME_pop_free(s->s3->tmp.peer_ca_names, X509_NAME_free);
+ s->s3->tmp.peer_ca_names = NULL;
+ return 1;
+}
+
+static EXT_RETURN tls_construct_certificate_authorities(SSL *s, WPACKET *pkt,
+ unsigned int context,
+ X509 *x,
+ size_t chainidx,
+ int *al)
+{
+ const STACK_OF(X509_NAME) *ca_sk = SSL_get0_CA_list(s);
+
+ if (ca_sk == NULL || sk_X509_NAME_num(ca_sk) == 0)
+ return EXT_RETURN_NOT_SENT;
+
+ if (!WPACKET_put_bytes_u16(pkt, TLSEXT_TYPE_certificate_authorities)
+ || !WPACKET_start_sub_packet_u16(pkt)
+ || !construct_ca_names(s, pkt)
+ || !WPACKET_close(pkt)) {
+ SSLerr(SSL_F_TLS_CONSTRUCT_CERTIFICATE_AUTHORITIES,
+ ERR_R_INTERNAL_ERROR);
+ return EXT_RETURN_FAIL;
+ }
+
+ return EXT_RETURN_SENT;
+}
+
+static int tls_parse_certificate_authorities(SSL *s, PACKET *pkt,
+ unsigned int context, X509 *x,
+ size_t chainidx, int *al)
+{
+ if (!parse_ca_names(s, pkt, al))
+ return 0;
+ if (PACKET_remaining(pkt) != 0) {
+ *al = SSL_AD_DECODE_ERROR;
return 0;
}
+ return 1;
+}
- if (!WPACKET_close(pkt)) {
- SSLerr(SSL_F_TLS_CONSTRUCT_EXTENSIONS, ERR_R_INTERNAL_ERROR);
+#ifndef OPENSSL_NO_SRTP
+static int init_srtp(SSL *s, unsigned int context)
+{
+ if (s->server)
+ s->srtp_profile = NULL;
+
+ return 1;
+}
+#endif
+
+static int final_sig_algs(SSL *s, unsigned int context, int sent, int *al)
+{
+ if (!sent && SSL_IS_TLS13(s) && !s->hit) {
+ *al = TLS13_AD_MISSING_EXTENSION;
+ SSLerr(SSL_F_FINAL_SIG_ALGS, SSL_R_MISSING_SIGALGS_EXTENSION);
+ return 0;
+ }
+
+ return 1;
+}
+
+#ifndef OPENSSL_NO_EC
+static int final_key_share(SSL *s, unsigned int context, int sent, int *al)
+{
+ if (!SSL_IS_TLS13(s))
+ return 1;
+
+ /* Nothing to do for key_share in an HRR */
+ if ((context & SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST) != 0)
+ return 1;
+
+ /*
+ * If
+ * we are a client
+ * AND
+ * we have no key_share
+ * AND
+ * (we are not resuming
+ * OR the kex_mode doesn't allow non key_share resumes)
+ * THEN
+ * fail;
+ */
+ if (!s->server
+ && !sent
+ && (!s->hit
+ || (s->ext.psk_kex_mode & TLSEXT_KEX_MODE_FLAG_KE) == 0)) {
+ /* Nothing left we can do - just fail */
+ *al = SSL_AD_MISSING_EXTENSION;
+ SSLerr(SSL_F_FINAL_KEY_SHARE, SSL_R_NO_SUITABLE_KEY_SHARE);
return 0;
}
+ /*
+ * If
+ * we are a server
+ * AND
+ * we have no key_share
+ * THEN
+ * If
+ * we didn't already send a HelloRetryRequest
+ * AND
+ * the client sent a key_share extension
+ * AND
+ * (we are not resuming
+ * OR the kex_mode allows key_share resumes)
+ * AND
+ * a shared group exists
+ * THEN
+ * send a HelloRetryRequest
+ * ELSE If
+ * we are not resuming
+ * OR
+ * the kex_mode doesn't allow non key_share resumes
+ * THEN
+ * fail;
+ */
+ if (s->server && s->s3->peer_tmp == NULL) {
+ /* No suitable share */
+ if (s->hello_retry_request == 0 && sent
+ && (!s->hit
+ || (s->ext.psk_kex_mode & TLSEXT_KEX_MODE_FLAG_KE_DHE)
+ != 0)) {
+ const unsigned char *pcurves, *pcurvestmp, *clntcurves;
+ size_t num_curves, clnt_num_curves, i;
+ unsigned int group_id = 0;
+
+ /* Check if a shared group exists */
+
+ /* Get the clients list of supported groups. */
+ if (!tls1_get_curvelist(s, 1, &clntcurves, &clnt_num_curves)) {
+ *al = SSL_AD_INTERNAL_ERROR;
+ SSLerr(SSL_F_FINAL_KEY_SHARE, ERR_R_INTERNAL_ERROR);
+ return 0;
+ }
+
+ /* Get our list of available groups */
+ if (!tls1_get_curvelist(s, 0, &pcurves, &num_curves)) {
+ *al = SSL_AD_INTERNAL_ERROR;
+ SSLerr(SSL_F_FINAL_KEY_SHARE, ERR_R_INTERNAL_ERROR);
+ return 0;
+ }
+
+ /* Find the first group we allow that is also in client's list */
+ for (i = 0, pcurvestmp = pcurves; i < num_curves;
+ i++, pcurvestmp += 2) {
+ group_id = bytestogroup(pcurvestmp);
+
+ if (check_in_list(s, group_id, clntcurves, clnt_num_curves, 1))
+ break;
+ }
+
+ if (i < num_curves) {
+ /* A shared group exists so send a HelloRetryRequest */
+ s->s3->group_id = group_id;
+ s->hello_retry_request = 1;
+ return 1;
+ }
+ }
+ if (!s->hit
+ || (s->ext.psk_kex_mode & TLSEXT_KEX_MODE_FLAG_KE) == 0) {
+ /* Nothing left we can do - just fail */
+ if (!sent)
+ *al = SSL_AD_MISSING_EXTENSION;
+ else
+ *al = SSL_AD_HANDSHAKE_FAILURE;
+ SSLerr(SSL_F_FINAL_KEY_SHARE, SSL_R_NO_SUITABLE_KEY_SHARE);
+ return 0;
+ }
+ }
+
+ /* We have a key_share so don't send any more HelloRetryRequest messages */
+ if (s->server)
+ s->hello_retry_request = 0;
+
+ /*
+ * For a client side resumption with no key_share we need to generate
+ * the handshake secret (otherwise this is done during key_share
+ * processing).
+ */
+ if (!sent && !s->server && !tls13_generate_handshake_secret(s, NULL, 0)) {
+ *al = SSL_AD_INTERNAL_ERROR;
+ SSLerr(SSL_F_FINAL_KEY_SHARE, ERR_R_INTERNAL_ERROR);
+ return 0;
+ }
+
+ return 1;
+}
+#endif
+
+static int init_psk_kex_modes(SSL *s, unsigned int context)
+{
+ s->ext.psk_kex_mode = TLSEXT_KEX_MODE_FLAG_NONE;
+ return 1;
+}
+
+int tls_psk_do_binder(SSL *s, const EVP_MD *md, const unsigned char *msgstart,
+ size_t binderoffset, const unsigned char *binderin,
+ unsigned char *binderout,
+ SSL_SESSION *sess, int sign)
+{
+ EVP_PKEY *mackey = NULL;
+ EVP_MD_CTX *mctx = NULL;
+ unsigned char hash[EVP_MAX_MD_SIZE], binderkey[EVP_MAX_MD_SIZE];
+ unsigned char finishedkey[EVP_MAX_MD_SIZE], tmpbinder[EVP_MAX_MD_SIZE];
+ const char resumption_label[] = "res binder";
+ size_t bindersize, hashsize = EVP_MD_size(md);
+ int ret = -1;
+
+ /* Generate the early_secret */
+ if (!tls13_generate_secret(s, md, NULL, sess->master_key,
+ sess->master_key_length,
+ (unsigned char *)&s->early_secret)) {
+ SSLerr(SSL_F_TLS_PSK_DO_BINDER, ERR_R_INTERNAL_ERROR);
+ goto err;
+ }
+
+ /*
+ * Create the handshake hash for the binder key...the messages so far are
+ * empty!
+ */
+ mctx = EVP_MD_CTX_new();
+ if (mctx == NULL
+ || EVP_DigestInit_ex(mctx, md, NULL) <= 0
+ || EVP_DigestFinal_ex(mctx, hash, NULL) <= 0) {
+ SSLerr(SSL_F_TLS_PSK_DO_BINDER, ERR_R_INTERNAL_ERROR);
+ goto err;
+ }
+
+ /* Generate the binder key */
+ if (!tls13_hkdf_expand(s, md, s->early_secret,
+ (unsigned char *)resumption_label,
+ sizeof(resumption_label) - 1, hash, binderkey,
+ hashsize)) {
+ SSLerr(SSL_F_TLS_PSK_DO_BINDER, ERR_R_INTERNAL_ERROR);
+ goto err;
+ }
+
+ /* Generate the finished key */
+ if (!tls13_derive_finishedkey(s, md, binderkey, finishedkey, hashsize)) {
+ SSLerr(SSL_F_TLS_PSK_DO_BINDER, ERR_R_INTERNAL_ERROR);
+ goto err;
+ }
+
+ if (EVP_DigestInit_ex(mctx, md, NULL) <= 0) {
+ SSLerr(SSL_F_TLS_PSK_DO_BINDER, ERR_R_INTERNAL_ERROR);
+ goto err;
+ }
+
+ /*
+ * Get a hash of the ClientHello up to the start of the binders. If we are
+ * following a HelloRetryRequest then this includes the hash of the first
+ * ClientHello and the HelloRetryRequest itself.
+ */
+ if (s->hello_retry_request) {
+ size_t hdatalen;
+ void *hdata;
+
+ hdatalen = BIO_get_mem_data(s->s3->handshake_buffer, &hdata);
+ if (hdatalen <= 0) {
+ SSLerr(SSL_F_TLS_PSK_DO_BINDER, SSL_R_BAD_HANDSHAKE_LENGTH);
+ goto err;
+ }
+
+ /*
+ * For servers the handshake buffer data will include the second
+ * ClientHello - which we don't want - so we need to take that bit off.
+ */
+ if (s->server) {
+ PACKET hashprefix, msg;
+
+ /* Find how many bytes are left after the first two messages */
+ if (!PACKET_buf_init(&hashprefix, hdata, hdatalen)
+ || !PACKET_forward(&hashprefix, 1)
+ || !PACKET_get_length_prefixed_3(&hashprefix, &msg)
+ || !PACKET_forward(&hashprefix, 1)
+ || !PACKET_get_length_prefixed_3(&hashprefix, &msg)) {
+ SSLerr(SSL_F_TLS_PSK_DO_BINDER, ERR_R_INTERNAL_ERROR);
+ goto err;
+ }
+ hdatalen -= PACKET_remaining(&hashprefix);
+ }
+
+ if (EVP_DigestUpdate(mctx, hdata, hdatalen) <= 0) {
+ SSLerr(SSL_F_TLS_PSK_DO_BINDER, ERR_R_INTERNAL_ERROR);
+ goto err;
+ }
+ }
+
+ if (EVP_DigestUpdate(mctx, msgstart, binderoffset) <= 0
+ || EVP_DigestFinal_ex(mctx, hash, NULL) <= 0) {
+ SSLerr(SSL_F_TLS_PSK_DO_BINDER, ERR_R_INTERNAL_ERROR);
+ goto err;
+ }
+
+ mackey = EVP_PKEY_new_mac_key(EVP_PKEY_HMAC, NULL, finishedkey, hashsize);
+ if (mackey == NULL) {
+ SSLerr(SSL_F_TLS_PSK_DO_BINDER, ERR_R_INTERNAL_ERROR);
+ goto err;
+ }
+
+ if (!sign)
+ binderout = tmpbinder;
+
+ bindersize = hashsize;
+ if (EVP_DigestSignInit(mctx, NULL, md, NULL, mackey) <= 0
+ || EVP_DigestSignUpdate(mctx, hash, hashsize) <= 0
+ || EVP_DigestSignFinal(mctx, binderout, &bindersize) <= 0
+ || bindersize != hashsize) {
+ SSLerr(SSL_F_TLS_PSK_DO_BINDER, ERR_R_INTERNAL_ERROR);
+ goto err;
+ }
+
+ if (sign) {
+ ret = 1;
+ } else {
+ /* HMAC keys can't do EVP_DigestVerify* - use CRYPTO_memcmp instead */
+ ret = (CRYPTO_memcmp(binderin, binderout, hashsize) == 0);
+ }
+
+ err:
+ OPENSSL_cleanse(binderkey, sizeof(binderkey));
+ OPENSSL_cleanse(finishedkey, sizeof(finishedkey));
+ EVP_PKEY_free(mackey);
+ EVP_MD_CTX_free(mctx);
+
+ return ret;
+}
+
+static int final_early_data(SSL *s, unsigned int context, int sent, int *al)
+{
+ if (!s->server || !sent)
+ return 1;
+
+ if (s->max_early_data == 0
+ || !s->hit
+ || s->session->ext.tick_identity != 0
+ || s->early_data_state != SSL_EARLY_DATA_ACCEPTING
+ || !s->ext.early_data_ok
+ || s->hello_retry_request
+ || s->s3->alpn_selected_len != s->session->ext.alpn_selected_len
+ || (s->s3->alpn_selected_len > 0
+ && memcmp(s->s3->alpn_selected, s->session->ext.alpn_selected,
+ s->s3->alpn_selected_len) != 0)) {
+ s->ext.early_data = SSL_EARLY_DATA_REJECTED;
+ } else {
+ s->ext.early_data = SSL_EARLY_DATA_ACCEPTED;
+
+ if (!tls13_change_cipher_state(s,
+ SSL3_CC_EARLY | SSL3_CHANGE_CIPHER_SERVER_READ)) {
+ *al = SSL_AD_INTERNAL_ERROR;
+ return 0;
+ }
+ }
return 1;
}
projects / openssl.git / blobdiff