From f393b7449dae2b81715fa84309c6ecf04be035d7 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Bodo=20M=C3=B6ller?= Date: Thu, 30 Mar 2006 02:35:09 +0000 Subject: [PATCH] Implement cipher-suite selection logic given Supported Point Formats Extension. Submitted by: Douglas Stebila --- ssl/s3_lib.c | 67 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 67 insertions(+) diff --git a/ssl/s3_lib.c b/ssl/s3_lib.c index aecf6d62a8..a488692579 100644 --- a/ssl/s3_lib.c +++ b/ssl/s3_lib.c @@ -152,6 +152,11 @@ #include #include "ssl_locl.h" #include "kssl_lcl.h" +#ifndef OPENSSL_NO_TLSEXT +#ifndef OPENSSL_NO_EC +#include "../crypto/ec/ec_lcl.h" +#endif /* OPENSSL_NO_EC */ +#endif /* OPENSSL_NO_TLSEXT */ #include #ifndef OPENSSL_NO_DH #include @@ -2039,6 +2044,11 @@ SSL_CIPHER *ssl3_choose_cipher(SSL *s, STACK_OF(SSL_CIPHER) *clnt, SSL_CIPHER *c,*ret=NULL; STACK_OF(SSL_CIPHER) *prio, *allow; int i,j,ok; +#ifndef OPENSSL_NO_TLSEXT +#ifndef OPENSSL_NO_EC + int ec_ok; +#endif /* OPENSSL_NO_EC */ +#endif /* OPENSSL_NO_TLSEXT */ CERT *cert; unsigned long alg,mask,emask; @@ -2124,6 +2134,63 @@ SSL_CIPHER *ssl3_choose_cipher(SSL *s, STACK_OF(SSL_CIPHER) *clnt, #endif } +#ifndef OPENSSL_NO_TLSEXT +#ifndef OPENSSL_NO_EC + if ( + /* if we are considering an ECC cipher suite that uses our certificate */ + (alg & SSL_aECDSA) + /* and we have an ECC certificate */ + && (s->cert->pkeys[SSL_PKEY_ECC].x509 != NULL) + /* and the client specified a Supported Point Formats extension */ + && ((s->session->tlsext_ecpointformatlist_length > 0) && (s->session->tlsext_ecpointformatlist != NULL)) + /* and our certificate's point is compressed */ + && ( + (s->cert->pkeys[SSL_PKEY_ECC].x509->cert_info != NULL) + && (s->cert->pkeys[SSL_PKEY_ECC].x509->cert_info->key != NULL) + && (s->cert->pkeys[SSL_PKEY_ECC].x509->cert_info->key->public_key != NULL) + && (s->cert->pkeys[SSL_PKEY_ECC].x509->cert_info->key->public_key->data != NULL) + && ( + (*(s->cert->pkeys[SSL_PKEY_ECC].x509->cert_info->key->public_key->data) == POINT_CONVERSION_COMPRESSED) + || (*(s->cert->pkeys[SSL_PKEY_ECC].x509->cert_info->key->public_key->data) == POINT_CONVERSION_COMPRESSED + 1) + ) + ) + ) + { + ec_ok = 0; + /* if our certificate's curve is over a field type that the client does not support + * then do not allow this cipher suite to be negotiated */ + if ( + (s->cert->pkeys[SSL_PKEY_ECC].privatekey->pkey.ec != NULL) + && (s->cert->pkeys[SSL_PKEY_ECC].privatekey->pkey.ec->group != NULL) + && (s->cert->pkeys[SSL_PKEY_ECC].privatekey->pkey.ec->group->meth != NULL) + && (EC_METHOD_get_field_type(s->cert->pkeys[SSL_PKEY_ECC].privatekey->pkey.ec->group->meth) == NID_X9_62_prime_field) + ) + { + for (j = 0; j < s->session->tlsext_ecpointformatlist_length; j++) + { + if (s->session->tlsext_ecpointformatlist[j] == TLSEXT_ECPOINTFORMAT_ansiX962_compressed_prime) + { + ec_ok = 1; + break; + } + } + } + else if (EC_METHOD_get_field_type(s->cert->pkeys[SSL_PKEY_ECC].privatekey->pkey.ec->group->meth) == NID_X9_62_characteristic_two_field) + { + for (j = 0; j < s->session->tlsext_ecpointformatlist_length; j++) + { + if (s->session->tlsext_ecpointformatlist[j] == TLSEXT_ECPOINTFORMAT_ansiX962_compressed_char2) + { + ec_ok = 1; + break; + } + } + } + ok = ok && ec_ok; + } +#endif /* OPENSSL_NO_EC */ +#endif /* OPENSSL_NO_TLSEXT */ + if (!ok) continue; j=sk_SSL_CIPHER_find(allow,c); if (j >= 0) -- 2.25.1