diff options
| -rw-r--r-- | include/openssl/ssl.h | 45 | ||||
| -rw-r--r-- | ssl/ssl_cert.c | 7 | ||||
| -rw-r--r-- | ssl/ssl_locl.h | 31 | ||||
| -rw-r--r-- | ssl/ssl_rsa.c | 29 | ||||
| -rw-r--r-- | ssl/statem/extensions.c | 160 | ||||
| -rw-r--r-- | ssl/statem/extensions_clnt.c | 6 | ||||
| -rw-r--r-- | ssl/statem/extensions_cust.c | 359 | ||||
| -rw-r--r-- | ssl/statem/statem_locl.h | 4 | ||||
| -rw-r--r-- | util/libssl.num | 1 |
9 files changed, 440 insertions, 202 deletions
diff --git a/include/openssl/ssl.h b/include/openssl/ssl.h index 8e2d934fde..8dbfe91f63 100644 --- a/include/openssl/ssl.h +++ b/include/openssl/ssl.h @@ -259,19 +259,21 @@ typedef int (*tls_session_secret_cb_fn) (SSL *s, void *secret, #define SSL_EXT_TLS_IMPLEMENTATION_ONLY 0x0004 /* Most extensions are not defined for SSLv3 but EXT_TYPE_renegotiate is */ #define SSL_EXT_SSL3_ALLOWED 0x0008 -/* Extension is only defined for TLS1.2 and above */ +/* Extension is only defined for TLS1.2 and below */ #define SSL_EXT_TLS1_2_AND_BELOW_ONLY 0x0010 /* Extension is only defined for TLS1.3 and above */ #define SSL_EXT_TLS1_3_ONLY 0x0020 -#define SSL_EXT_CLIENT_HELLO 0x0040 +/* Ignore this extension during parsing if we are resuming */ +#define SSL_EXT_IGNORE_ON_RESUMPTION 0x0040 +#define SSL_EXT_CLIENT_HELLO 0x0080 /* Really means TLS1.2 or below */ -#define SSL_EXT_TLS1_2_SERVER_HELLO 0x0080 -#define SSL_EXT_TLS1_3_SERVER_HELLO 0x0100 -#define SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS 0x0200 -#define SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST 0x0400 -#define SSL_EXT_TLS1_3_CERTIFICATE 0x0800 -#define SSL_EXT_TLS1_3_NEW_SESSION_TICKET 0x1000 -#define SSL_EXT_TLS1_3_CERTIFICATE_REQUEST 0x2000 +#define SSL_EXT_TLS1_2_SERVER_HELLO 0x0100 +#define SSL_EXT_TLS1_3_SERVER_HELLO 0x0200 +#define SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS 0x0400 +#define SSL_EXT_TLS1_3_HELLO_RETRY_REQUEST 0x0800 +#define SSL_EXT_TLS1_3_CERTIFICATE 0x1000 +#define SSL_EXT_TLS1_3_NEW_SESSION_TICKET 0x2000 +#define SSL_EXT_TLS1_3_CERTIFICATE_REQUEST 0x4000 /* Typedefs for handling custom extensions */ @@ -286,6 +288,23 @@ typedef int (*custom_ext_parse_cb) (SSL *s, unsigned int ext_type, const unsigned char *in, size_t inlen, int *al, void *parse_arg); + +typedef int (*custom_ext_add_cb_ex) (SSL *s, unsigned int ext_type, + unsigned int context, + const unsigned char **out, + size_t *outlen, X509 *x, size_t chainidx, + int *al, void *add_arg); + +typedef void (*custom_ext_free_cb_ex) (SSL *s, unsigned int ext_type, + unsigned int context, + const unsigned char *out, void *add_arg); + +typedef int (*custom_ext_parse_cb_ex) (SSL *s, unsigned int ext_type, + unsigned int context, + const unsigned char *in, + size_t inlen, X509 *x, size_t chainidx, + int *al, void *parse_arg); + /* Typedef for verification callback */ typedef int (*SSL_verify_cb)(int preverify_ok, X509_STORE_CTX *x509_ctx); @@ -779,6 +798,14 @@ __owur int SSL_CTX_add_server_custom_ext(SSL_CTX *ctx, unsigned int ext_type, custom_ext_parse_cb parse_cb, void *parse_arg); +__owur int SSL_CTX_add_custom_ext(SSL_CTX *ctx, unsigned int ext_type, + unsigned int context, + custom_ext_add_cb_ex add_cb, + custom_ext_free_cb_ex free_cb, + void *add_arg, + custom_ext_parse_cb_ex parse_cb, + void *parse_arg); + __owur int SSL_extension_supported(unsigned int ext_type); # define SSL_NOTHING 1 diff --git a/ssl/ssl_cert.c b/ssl/ssl_cert.c index a4e7977012..3a85ede638 100644 --- a/ssl/ssl_cert.c +++ b/ssl/ssl_cert.c @@ -190,9 +190,7 @@ CERT *ssl_cert_dup(CERT *cert) ret->sec_level = cert->sec_level; ret->sec_ex = cert->sec_ex; - if (!custom_exts_copy(&ret->cli_ext, &cert->cli_ext)) - goto err; - if (!custom_exts_copy(&ret->srv_ext, &cert->srv_ext)) + if (!custom_exts_copy(&ret->custext, &cert->custext)) goto err; #ifndef OPENSSL_NO_PSK if (cert->psk_identity_hint) { @@ -254,8 +252,7 @@ void ssl_cert_free(CERT *c) OPENSSL_free(c->ctype); X509_STORE_free(c->verify_store); X509_STORE_free(c->chain_store); - custom_exts_free(&c->cli_ext); - custom_exts_free(&c->srv_ext); + custom_exts_free(&c->custext); #ifndef OPENSSL_NO_PSK OPENSSL_free(c->psk_identity_hint); #endif diff --git a/ssl/ssl_locl.h b/ssl/ssl_locl.h index f53293109b..a9ac840e10 100644 --- a/ssl/ssl_locl.h +++ b/ssl/ssl_locl.h @@ -1619,14 +1619,21 @@ struct cert_pkey_st { typedef struct { unsigned short ext_type; /* + * Set to 1 if this is only for the server side, 0 if it is only for the + * client side, or -1 if it is either. + */ + int server; + /* The context which this extension applies to */ + unsigned int context; + /* * Per-connection flags relating to this extension type: not used if * part of an SSL_CTX structure. */ uint32_t ext_flags; - custom_ext_add_cb add_cb; - custom_ext_free_cb free_cb; + custom_ext_add_cb_ex add_cb; + custom_ext_free_cb_ex free_cb; void *add_arg; - custom_ext_parse_cb parse_cb; + custom_ext_parse_cb_ex parse_cb; void *parse_arg; } custom_ext_method; @@ -1706,9 +1713,8 @@ typedef struct cert_st { */ X509_STORE *chain_store; X509_STORE *verify_store; - /* Custom extension methods for server and client */ - custom_ext_methods cli_ext; - custom_ext_methods srv_ext; + /* Custom extensions */ + custom_ext_methods custext; /* Security callback */ int (*sec_cb) (const SSL *s, const SSL_CTX *ctx, int op, int bits, int nid, void *other, void *ex); @@ -2436,15 +2442,18 @@ __owur int srp_generate_server_master_secret(SSL *s); __owur int srp_generate_client_master_secret(SSL *s); __owur int srp_verify_server_param(SSL *s, int *al); -/* t1_ext.c */ +/* statem/extensions_cust.c */ + +custom_ext_method *custom_ext_find(const custom_ext_methods *exts, int server, + unsigned int ext_type, size_t *idx); void custom_ext_init(custom_ext_methods *meths); -__owur int custom_ext_parse(SSL *s, int server, - unsigned int ext_type, +__owur int custom_ext_parse(SSL *s, unsigned int context, unsigned int ext_type, const unsigned char *ext_data, size_t ext_size, - int *al); -__owur int custom_ext_add(SSL *s, int server, WPACKET *pkt, int *al); + X509 *x, size_t chainidx, int *al); +__owur int custom_ext_add(SSL *s, int context, WPACKET *pkt, X509 *x, + size_t chainidx, int maxversion, int *al); __owur int custom_exts_copy(custom_ext_methods *dst, const custom_ext_methods *src); diff --git a/ssl/ssl_rsa.c b/ssl/ssl_rsa.c index a94fb13b89..ecf2ff3e73 100644 --- a/ssl/ssl_rsa.c +++ b/ssl/ssl_rsa.c @@ -797,26 +797,15 @@ static int serverinfo_process_buffer(const unsigned char *serverinfo, /* Register callbacks for extensions */ ext_type = (serverinfo[0] << 8) + serverinfo[1]; - if (ctx) { - int have_ext_cbs = 0; - size_t i; - custom_ext_methods *exts = &ctx->cert->srv_ext; - custom_ext_method *meth = exts->meths; - - for (i = 0; i < exts->meths_count; i++, meth++) { - if (ext_type == meth->ext_type) { - have_ext_cbs = 1; - break; - } - } - - if (!have_ext_cbs && !SSL_CTX_add_server_custom_ext(ctx, ext_type, - serverinfo_srv_add_cb, - NULL, NULL, - serverinfo_srv_parse_cb, - NULL)) - return 0; - } + if (ctx != NULL + && custom_ext_find(&ctx->cert->custext, 1, ext_type, NULL) + == NULL + && !SSL_CTX_add_server_custom_ext(ctx, ext_type, + serverinfo_srv_add_cb, + NULL, NULL, + serverinfo_srv_parse_cb, + NULL)) + return 0; serverinfo += 2; serverinfo_length -= 2; diff --git a/ssl/statem/extensions.c b/ssl/statem/extensions.c index c2e0411240..49a7156a2c 100644 --- a/ssl/statem/extensions.c +++ b/ssl/statem/extensions.c @@ -329,6 +329,23 @@ static const EXTENSION_DEFINITION ext_defs[] = { } }; +/* Check whether an extension's context matches the current context */ +static int validate_context(SSL *s, unsigned int extctx, unsigned int thisctx) +{ + /* Check we're allowed to use this extension in this context */ + if ((thisctx & extctx) == 0) + return 0; + + 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 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 @@ -345,38 +362,31 @@ static int verify_extension(SSL *s, unsigned int context, unsigned int type, for (i = 0, thisext = ext_defs; i < builtin_num; i++, thisext++) { if (type == thisext->type) { - /* Check we're allowed to use this extension in this context */ - if ((context & thisext->context) == 0) + if (!validate_context(s, thisext->context, context)) return 0; - if (SSL_IS_DTLS(s)) { - if ((thisext->context & SSL_EXT_TLS_ONLY) != 0) - return 0; - } else if ((thisext->context & SSL_EXT_DTLS_ONLY) != 0) { - return 0; - } - *found = &rawexlist[i]; return 1; } } - if ((context & (SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO)) == 0) { - /* - * Custom extensions only apply to <=TLS1.2. This extension is unknown - * in this context - we allow it - */ - *found = NULL; - return 1; - } - /* Check the custom extensions */ if (meths != NULL) { - for (i = builtin_num; i < builtin_num + meths->meths_count; i++) { - if (meths->meths[i - builtin_num].ext_type == type) { - *found = &rawexlist[i]; - return 1; - } + size_t offset = 0; + int server = -1; + custom_ext_method *meth = NULL; + + if ((context & SSL_EXT_CLIENT_HELLO) != 0) + server = 1; + else if ((context & SSL_EXT_TLS1_2_SERVER_HELLO) != 0) + server = 0; + + meth = custom_ext_find(meths, server, type, &offset); + if (meth != NULL) { + if (!validate_context(s, meth->context, context)) + return 0; + *found = &rawexlist[offset + builtin_num]; + return 1; } } @@ -390,8 +400,7 @@ static int verify_extension(SSL *s, unsigned int context, unsigned int type, * 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 extension_is_relevant(SSL *s, unsigned int extctx, - unsigned int thisctx) +int extension_is_relevant(SSL *s, unsigned int extctx, unsigned int thisctx) { if ((SSL_IS_DTLS(s) && (extctx & SSL_EXT_TLS_IMPLEMENTATION_ONLY) != 0) @@ -399,7 +408,8 @@ static int extension_is_relevant(SSL *s, unsigned int extctx, && (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)) + || (!SSL_IS_TLS13(s) && (extctx & SSL_EXT_TLS1_3_ONLY) != 0) + || (s->hit && (extctx & SSL_EXT_IGNORE_ON_RESUMPTION) != 0)) return 0; return 1; @@ -427,7 +437,7 @@ int tls_collect_extensions(SSL *s, PACKET *packet, unsigned int context, PACKET extensions = *packet; size_t i = 0; size_t num_exts; - custom_ext_methods *exts = NULL; + custom_ext_methods *exts = &s->cert->custext; RAW_EXTENSION *raw_extensions = NULL; const EXTENSION_DEFINITION *thisexd; @@ -437,12 +447,8 @@ int tls_collect_extensions(SSL *s, PACKET *packet, unsigned int context, * Initialise server side custom extensions. Client side is done during * construction of extensions for the ClientHello. */ - if ((context & SSL_EXT_CLIENT_HELLO) != 0) { - exts = &s->cert->srv_ext; - custom_ext_init(&s->cert->srv_ext); - } else if ((context & SSL_EXT_TLS1_2_SERVER_HELLO) != 0) { - exts = &s->cert->cli_ext; - } + 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)); @@ -560,21 +566,11 @@ int tls_parse_extension(SSL *s, TLSEXT_INDEX idx, int context, */ } - /* - * This is a custom extension. We only allow this if it is a non - * resumed session on the server side. - *chain - * 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 - & (SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO)) != 0 - && custom_ext_parse(s, s->server, currext->type, - PACKET_data(&currext->data), - PACKET_remaining(&currext->data), - al) <= 0) + /* 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; @@ -595,11 +591,7 @@ int tls_parse_all_extensions(SSL *s, int context, RAW_EXTENSION *exts, X509 *x, const EXTENSION_DEFINITION *thisexd; /* Calculate the number of extensions in the extensions list */ - if ((context & SSL_EXT_CLIENT_HELLO) != 0) { - numexts += s->cert->srv_ext.meths_count; - } else if ((context & SSL_EXT_TLS1_2_SERVER_HELLO) != 0) { - numexts += s->cert->cli_ext.meths_count; - } + numexts += s->cert->custext.meths_count; /* Parse each extension in turn */ for (i = 0; i < numexts; i++) { @@ -621,6 +613,30 @@ int tls_parse_all_extensions(SSL *s, int context, RAW_EXTENSION *exts, X509 *x, 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 @@ -634,7 +650,7 @@ int tls_construct_extensions(SSL *s, WPACKET *pkt, unsigned int context, X509 *x, size_t chainidx, int *al) { size_t i; - int addcustom = 0, min_version, max_version = 0, reason, tmpal; + int min_version, max_version = 0, reason, tmpal; const EXTENSION_DEFINITION *thisexd; /* @@ -667,21 +683,10 @@ int tls_construct_extensions(SSL *s, WPACKET *pkt, unsigned int context, /* Add custom extensions first */ if ((context & SSL_EXT_CLIENT_HELLO) != 0) { - custom_ext_init(&s->cert->cli_ext); - addcustom = 1; - } else if ((context & SSL_EXT_TLS1_2_SERVER_HELLO) != 0) { - /* - * 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. - */ - addcustom = 1; + /* On the server side with initiase during ClientHello parsing */ + custom_ext_init(&s->cert->custext); } - - if (addcustom && !custom_ext_add(s, s->server, pkt, &tmpal)) { + if (!custom_ext_add(s, context, pkt, x, chainidx, max_version, &tmpal)) { SSLerr(SSL_F_TLS_CONSTRUCT_EXTENSIONS, ERR_R_INTERNAL_ERROR); goto err; } @@ -691,28 +696,13 @@ int tls_construct_extensions(SSL *s, WPACKET *pkt, unsigned int context, size_t chainidx, int *al); /* Skip if not relevant for our context */ - if ((thisexd->context & context) == 0) + if (!should_add_extension(s, thisexd->context, context, max_version)) continue; construct = s->server ? thisexd->construct_stoc : thisexd->construct_ctos; - /* Check if this extension is defined for our protocol. If not, skip */ - if ((SSL_IS_DTLS(s) - && (thisexd->context & SSL_EXT_TLS_IMPLEMENTATION_ONLY) - != 0) - || (s->version == SSL3_VERSION - && (thisexd->context & SSL_EXT_SSL3_ALLOWED) == 0) - || (SSL_IS_TLS13(s) - && (thisexd->context & SSL_EXT_TLS1_2_AND_BELOW_ONLY) - != 0) - || (!SSL_IS_TLS13(s) - && (thisexd->context & SSL_EXT_TLS1_3_ONLY) != 0 - && (context & SSL_EXT_CLIENT_HELLO) == 0) - || ((thisexd->context & SSL_EXT_TLS1_3_ONLY) != 0 - && (context & SSL_EXT_CLIENT_HELLO) != 0 - && (SSL_IS_DTLS(s) || max_version < TLS1_3_VERSION)) - || construct == NULL) + if (construct == NULL) continue; if (!construct(s, pkt, context, x, chainidx, &tmpal)) diff --git a/ssl/statem/extensions_clnt.c b/ssl/statem/extensions_clnt.c index af89494507..7d2a4b04a5 100644 --- a/ssl/statem/extensions_clnt.c +++ b/ssl/statem/extensions_clnt.c @@ -1092,8 +1092,10 @@ int tls_parse_stoc_sct(SSL *s, PACKET *pkt, unsigned int context, X509 *x, } } } else { - if (custom_ext_parse(s, 0, TLSEXT_TYPE_signed_certificate_timestamp, - PACKET_data(pkt), PACKET_remaining(pkt), al) <= 0) + if (custom_ext_parse(s, context, + TLSEXT_TYPE_signed_certificate_timestamp, + PACKET_data(pkt), PACKET_remaining(pkt), + x, chainidx, al) <= 0) return 0; } diff --git a/ssl/statem/extensions_cust.c b/ssl/statem/extensions_cust.c index 374fe1e55e..ec1ab6d539 100644 --- a/ssl/statem/extensions_cust.c +++ b/ssl/statem/extensions_cust.c @@ -9,18 +9,86 @@ /* Custom extension utility functions */ +#include <assert.h> #include <openssl/ct.h> #include "../ssl_locl.h" +#include "statem_locl.h" -/* Find a custom extension from the list. */ -static custom_ext_method *custom_ext_find(const custom_ext_methods *exts, - unsigned int ext_type) +typedef struct { + void *add_arg; + custom_ext_add_cb add_cb; + custom_ext_free_cb free_cb; +} custom_ext_add_cb_wrap; + +typedef struct { + void *parse_arg; + custom_ext_parse_cb parse_cb; +} custom_ext_parse_cb_wrap; + +/* + * Provide thin wrapper callbacks which convert new style arguments to old style + */ +static int custom_ext_add_old_cb_wrap(SSL *s, unsigned int ext_type, + unsigned int context, + const unsigned char **out, + size_t *outlen, X509 *x, size_t chainidx, + int *al, void *add_arg) +{ + custom_ext_add_cb_wrap *add_cb_wrap = (custom_ext_add_cb_wrap *)add_arg; + + if (add_cb_wrap->add_cb == NULL) + return 1; + + return add_cb_wrap->add_cb(s, ext_type, out, outlen, al, + add_cb_wrap->add_arg); +} + +static void custom_ext_free_old_cb_wrap(SSL *s, unsigned int ext_type, + unsigned int context, + const unsigned char *out, void *add_arg) +{ + custom_ext_add_cb_wrap *add_cb_wrap = (custom_ext_add_cb_wrap *)add_arg; + + if (add_cb_wrap->free_cb == NULL) + return; + + add_cb_wrap->free_cb(s, ext_type, out, add_cb_wrap->add_arg); +} + +static int custom_ext_parse_old_cb_wrap(SSL *s, unsigned int ext_type, + unsigned int context, + const unsigned char *in, + size_t inlen, X509 *x, size_t chainidx, + int *al, void *parse_arg) +{ + custom_ext_parse_cb_wrap *parse_cb_wrap = + (custom_ext_parse_cb_wrap *)parse_arg; + + return parse_cb_wrap->parse_cb(s, ext_type, in, inlen, al, + parse_cb_wrap->parse_arg); +} + +/* + * Find a custom extension from the list. The |server| param is there to + * support the legacy API where custom extensions for client and server could + * be set independently on the same SSL_CTX. It is set to 1 if we are trying + * to find a method relevant to the server, 0 for the client, or -1 if we don't + * care + */ +custom_ext_method *custom_ext_find(const custom_ext_methods *exts, int server, + unsigned int ext_type, size_t *idx) { size_t i; + custom_ext_method *meth = exts->meths; for (i = 0; i < exts->meths_count; i++, meth++) { - if (ext_type == meth->ext_type) + if (ext_type == meth->ext_type + && (server == -1 || server == meth->server + || meth->server == -1)) { + if (idx != NULL) + *idx = i; return meth; + } } return NULL; } @@ -37,46 +105,63 @@ void custom_ext_init(custom_ext_methods *exts) } /* Pass received custom extension data to the application for parsing. */ -int custom_ext_parse(SSL *s, int server, - unsigned int ext_type, - const unsigned char *ext_data, size_t ext_size, int *al) +int custom_ext_parse(SSL *s, unsigned int context, unsigned int ext_type, + const unsigned char *ext_data, size_t ext_size, X509 *x, + size_t chainidx, int *al) { - custom_ext_methods *exts = server ? &s->cert->srv_ext : &s->cert->cli_ext; + custom_ext_methods *exts = &s->cert->custext; custom_ext_method *meth; - meth = custom_ext_find(exts, ext_type); + int server = -1; + + if ((context & (SSL_EXT_CLIENT_HELLO | SSL_EXT_TLS1_2_SERVER_HELLO)) != 0) + server = s->server; + + meth = custom_ext_find(exts, server, ext_type, NULL); /* If not found return success */ if (!meth) return 1; - if (!server) { + + /* Check if extension is defined for our protocol. If not, skip */ + if (!extension_is_relevant(s, meth->context, context)) + return 1; + + if ((context & (SSL_EXT_TLS1_2_SERVER_HELLO + | SSL_EXT_TLS1_3_SERVER_HELLO + | SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS)) != 0) { /* - * If it's ServerHello we can't have any extensions not sent in - * ClientHello. + * If it's ServerHello or EncryptedExtensions we can't have any + * extensions not sent in ClientHello. */ - if (!(meth->ext_flags & SSL_EXT_FLAG_SENT)) { + if ((meth->ext_flags & SSL_EXT_FLAG_SENT) == 0) { *al = TLS1_AD_UNSUPPORTED_EXTENSION; return 0; } } - /* If already present it's a duplicate */ - if (meth->ext_flags & SSL_EXT_FLAG_RECEIVED) { - *al = TLS1_AD_DECODE_ERROR; - return 0; - } - meth->ext_flags |= SSL_EXT_FLAG_RECEIVED; + + /* + * Extensions received in the ClientHello are marked with the + * SSL_EXT_FLAG_RECEIVED. This is so we know to add the equivalent + * extensions in the ServerHello/EncryptedExtensions message + */ + if ((context & SSL_EXT_CLIENT_HELLO) != 0) + meth->ext_flags |= SSL_EXT_FLAG_RECEIVED; + /* If no parse function set return success */ if (!meth->parse_cb) return 1; - return meth->parse_cb(s, ext_type, ext_data, ext_size, al, meth->parse_arg); + return meth->parse_cb(s, ext_type, context, ext_data, ext_size, x, chainidx, + al, meth->parse_arg); } /* * Request custom extension data from the application and add to the return * buffer. */ -int custom_ext_add(SSL *s, int server, WPACKET *pkt, int *al) +int custom_ext_add(SSL *s, int context, WPACKET *pkt, X509 *x, size_t chainidx, + int maxversion, int *al) { - custom_ext_methods *exts = server ? &s->cert->srv_ext : &s->cert->cli_ext; + custom_ext_methods *exts = &s->cert->custext; custom_ext_method *meth; size_t i; @@ -86,20 +171,30 @@ int custom_ext_add(SSL *s, int server, WPACKET *pkt, int *al) meth = exts->meths + i; - if (server) { + if (!should_add_extension(s, meth->context, context, maxversion)) + continue; + + if ((context & (SSL_EXT_TLS1_2_SERVER_HELLO + | SSL_EXT_TLS1_3_SERVER_HELLO + | SSL_EXT_TLS1_3_ENCRYPTED_EXTENSIONS)) != 0) { /* - * For ServerHello only send extensions present in ClientHello. + * For ServerHello/EncryptedExtensions only send extensions present + * in ClientHello. */ if (!(meth->ext_flags & SSL_EXT_FLAG_RECEIVED)) continue; - /* If callback absent for server skip it */ - if (!meth->add_cb) - continue; } - if (meth->add_cb) { + /* + * We skip it if the callback is absent - except for a ClientHello where + * we add an empty extension. + */ + if ((context & SSL_EXT_CLIENT_HELLO) == 0 && meth->add_cb == NULL) + continue; + + if (meth->add_cb != NULL) { int cb_retval = 0; - cb_retval = meth->add_cb(s, meth->ext_type, - &out, &outlen, al, meth->add_arg); + cb_retval = meth->add_cb(s, meth->ext_type, context, &out, &outlen, + x, chainidx, al, meth->add_arg); if (cb_retval < 0) return 0; /* error */ if (cb_retval == 0) @@ -113,18 +208,20 @@ int custom_ext_add(SSL *s, int server, WPACKET *pkt, int *al) *al = SSL_AD_INTERNAL_ERROR; return 0; } - /* - * We can't send duplicates: code logic should prevent this. - */ - OPENSSL_assert(!(meth->ext_flags & SSL_EXT_FLAG_SENT)); - /* - * Indicate extension has been sent: this is both a sanity check to - * ensure we don't send duplicate extensions and indicates that it is - * not an error if the extension is present in ServerHello. - */ - meth->ext_flags |= SSL_EXT_FLAG_SENT; + if ((context & SSL_EXT_CLIENT_HELLO) != 0) { + /* + * We can't send duplicates: code logic should prevent this. + */ + assert(!(meth->ext_flags & SSL_EXT_FLAG_SENT)); + /* + * Indicate extension has been sent: this is both a sanity check to + * ensure we don't send duplicate extensions and indicates that it + * is not an error if the extension is present in ServerHello. + */ + meth->ext_flags |= SSL_EXT_FLAG_SENT; + } if (meth->free_cb) - meth->free_cb(s, meth->ext_type, out, meth->add_arg); + meth->free_cb(s, meth->ext_type, context, out, meth->add_arg); } return 1; } @@ -132,49 +229,120 @@ int custom_ext_add(SSL *s, int server, WPACKET *pkt, int *al) /* Copy table of custom extensions */ int custom_exts_copy(custom_ext_methods *dst, const custom_ext_methods *src) { - if (src->meths_count) { + size_t i; + int err = 0; + + if (src->meths_count > 0) { dst->meths = OPENSSL_memdup(src->meths, sizeof(custom_ext_method) * src->meths_count); if (dst->meths == NULL) return 0; dst->meths_count = src->meths_count; + + for (i = 0; i < src->meths_count; i++) { + custom_ext_method *methsrc = src->meths + i; + custom_ext_method *methdst = dst->meths + i; + + if (methsrc->add_cb != custom_ext_add_old_cb_wrap) + continue; + + /* + * We have found an old style API wrapper. We need to copy the + * arguments too. + */ + + if (err) { + methdst->add_arg = NULL; + methdst->parse_arg = NULL; + continue; + } + + methdst->add_arg = OPENSSL_memdup(methsrc->add_arg, + sizeof(custom_ext_add_cb_wrap)); + methdst->parse_arg = OPENSSL_memdup(methsrc->parse_arg, + sizeof(custom_ext_parse_cb_wrap)); + + if (methdst->add_arg == NULL || methdst->parse_arg == NULL) + err = 1; + } + } + + if (err) { + custom_exts_free(dst); + return 0; } + return 1; } void custom_exts_free(custom_ext_methods *exts) { + size_t i; + + for (i = 0; i < exts->meths_count; i++) { + custom_ext_method *meth = exts->meths + i; + + if (meth->add_cb != custom_ext_add_old_cb_wrap) + continue; + + /* Old style API wrapper. Need to free the arguments too */ + OPENSSL_free(meth->add_arg); + OPENSSL_free(meth->parse_arg); + } OPENSSL_free(exts->meths); } -/* Set callbacks for a custom extension. */ -static int custom_ext_meth_add(custom_ext_methods *exts, - unsigned int ext_type, - custom_ext_add_cb add_cb, - custom_ext_free_cb free_cb, - void *add_arg, - custom_ext_parse_cb parse_cb, void *parse_arg) +/* Return true if a client custom extension exists, false otherwise */ +int SSL_CTX_has_client_custom_ext(const SSL_CTX *ctx, unsigned int ext_type) { + return custom_ext_find(&ctx->cert->custext, 0, ext_type, NULL) != NULL; +} + +static int add_custom_ext_intern(SSL_CTX *ctx, int server, + unsigned int ext_type, + unsigned int context, + custom_ext_add_cb_ex add_cb, + custom_ext_free_cb_ex free_cb, + void *add_arg, + custom_ext_parse_cb_ex parse_cb, + void *parse_arg) +{ + custom_ext_methods *exts = &ctx->cert->custext; custom_ext_method *meth, *tmp; + /* * Check application error: if add_cb is not set free_cb will never be * called. */ if (!add_cb && free_cb) return 0; + +#ifndef OPENSSL_NO_CT + /* + * We don't want applications registering callbacks for SCT extensions + * whilst simultaneously using the built-in SCT validation features, as + * these two things may not play well together. + */ + if (ext_type == TLSEXT_TYPE_signed_certificate_timestamp + && (context & SSL_EXT_CLIENT_HELLO) != 0 + && SSL_CTX_ct_is_enabled(ctx)) + return 0; +#endif + /* * Don't add if extension supported internally, but make exception * for extension types that previously were not supported, but now are. */ - if (SSL_extension_supported(ext_type) && - ext_type != TLSEXT_TYPE_signed_certificate_timestamp) + if (SSL_extension_supported(ext_type) + && ext_type != TLSEXT_TYPE_signed_certificate_timestamp) return 0; + /* Extension type must fit in 16 bits */ if (ext_type > 0xffff) return 0; /* Search for duplicate */ - if (custom_ext_find(exts, ext_type)) + if (custom_ext_find(exts, server, ext_type, NULL)) return 0; tmp = OPENSSL_realloc(exts->meths, (exts->meths_count + 1) * sizeof(custom_ext_method)); @@ -185,6 +353,8 @@ static int custom_ext_meth_add(custom_ext_methods *exts, exts->meths = tmp; meth = exts->meths + exts->meths_count; memset(meth, 0, sizeof(*meth)); + meth->server = server; + meth->context = context; meth->parse_cb = parse_cb; meth->add_cb = |