diff options
author | Bodo Möller <bodo@openssl.org> | 2006-03-11 23:46:37 +0000 |
---|---|---|
committer | Bodo Möller <bodo@openssl.org> | 2006-03-11 23:46:37 +0000 |
commit | 36ca4ba63d083da6f9d4598f18f17a8c32c8eca2 (patch) | |
tree | 1744a6165454e79e9c3cd76b4c33d72ff945e8d3 /ssl/t1_lib.c | |
parent | ed4a1d12b96ec9cdd927c116be8277654666c430 (diff) |
Implement the Supported Point Formats Extension for ECC ciphersuites
Submitted by: Douglas Stebila
Diffstat (limited to 'ssl/t1_lib.c')
-rw-r--r-- | ssl/t1_lib.c | 248 |
1 files changed, 247 insertions, 1 deletions
diff --git a/ssl/t1_lib.c b/ssl/t1_lib.c index d591daaff6..7f42cee22a 100644 --- a/ssl/t1_lib.c +++ b/ssl/t1_lib.c @@ -181,6 +181,22 @@ unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *p, unsigned cha memcpy(ret, s->tlsext_hostname, size_str); ret+=size_str; } +#ifndef OPENSSL_NO_EC + if (s->tlsext_ecpointformatlist != NULL) + { + /* Add TLS extension ECPointFormats to the ClientHello message */ + long lenmax; + + if ((lenmax = limit - p - 5) < 0) return NULL; + if (s->tlsext_ecpointformatlist_length > (unsigned long)lenmax) return NULL; + + s2n(TLSEXT_TYPE_ec_point_formats,ret); + s2n(s->tlsext_ecpointformatlist_length + 1,ret); + *(ret++) = (unsigned char) s->tlsext_ecpointformatlist_length; + memcpy(ret, s->tlsext_ecpointformatlist, s->tlsext_ecpointformatlist_length); + ret+=s->tlsext_ecpointformatlist_length; + } +#endif /* OPENSSL_NO_EC */ if ((extdatalen = ret-p-2)== 0) return p; @@ -204,6 +220,22 @@ unsigned char *ssl_add_serverhello_tlsext(SSL *s, unsigned char *p, unsigned cha s2n(TLSEXT_TYPE_server_name,ret); s2n(0,ret); } +#ifndef OPENSSL_NO_EC + if (s->tlsext_ecpointformatlist != NULL) + { + /* Add TLS extension ECPointFormats to the ServerHello message */ + long lenmax; + + if ((lenmax = limit - p - 5) < 0) return NULL; + if (s->tlsext_ecpointformatlist_length > (unsigned long)lenmax) return NULL; + + s2n(TLSEXT_TYPE_ec_point_formats,ret); + s2n(s->tlsext_ecpointformatlist_length + 1,ret); + *(ret++) = (unsigned char) s->tlsext_ecpointformatlist_length; + memcpy(ret, s->tlsext_ecpointformatlist, s->tlsext_ecpointformatlist_length); + ret+=s->tlsext_ecpointformatlist_length; + } +#endif /* OPENSSL_NO_EC */ if ((extdatalen = ret-p-2)== 0) return p; @@ -314,8 +346,37 @@ int ssl_parse_clienthello_tlsext(SSL *s, unsigned char **p, unsigned char *d, in } } +#ifndef OPENSSL_NO_EC + else if (type == TLSEXT_TYPE_ec_point_formats) + { + unsigned char *sdata = data; + int ecpointformatlist_length = *(sdata++); + int i; + + if (ecpointformatlist_length != size - 1) + { + *al = TLS1_AD_DECODE_ERROR; + return 0; + } + s->session->tlsext_ecpointformatlist_length = 0; + if ((s->session->tlsext_ecpointformatlist = OPENSSL_malloc(ecpointformatlist_length)) == NULL) + { + *al = TLS1_AD_INTERNAL_ERROR; + return 0; + } + s->session->tlsext_ecpointformatlist_length = ecpointformatlist_length; + memcpy(s->session->tlsext_ecpointformatlist, sdata, ecpointformatlist_length); +#if 0 + fprintf(stderr,"ssl_parse_clienthello_tlsext s->session->tlsext_ecpointformatlist (length=%i) ", s->session->tlsext_ecpointformatlist_length); + sdata = s->session->tlsext_ecpointformatlist; + for (i = 0; i < s->session->tlsext_ecpointformatlist_length; i++) + fprintf(stderr,"%i ",*(sdata++)); + fprintf(stderr,"\n"); +#endif + } data+=size; } +#endif /* OPENSSL_NO_EC */ *p = data; return 1; @@ -329,6 +390,9 @@ int ssl_parse_serverhello_tlsext(SSL *s, unsigned char **p, unsigned char *d, in unsigned char *data = *p; int tlsext_servername = 0; +#ifndef OPENSSL_NO_EC + int tlsext_ecpointformats = 0; +#endif /* OPENSSL_NO_EC */ if (data >= (d+n-2)) return 1; @@ -353,8 +417,38 @@ int ssl_parse_serverhello_tlsext(SSL *s, unsigned char **p, unsigned char *d, in tlsext_servername = 1; } +#ifndef OPENSSL_NO_EC + else if (type == TLSEXT_TYPE_ec_point_formats) + { + unsigned char *sdata = data; + int ecpointformatlist_length = *(sdata++); + int i; + + if (ecpointformatlist_length != size - 1) + { + *al = TLS1_AD_DECODE_ERROR; + return 0; + } + s->session->tlsext_ecpointformatlist_length = 0; + if ((s->session->tlsext_ecpointformatlist = OPENSSL_malloc(ecpointformatlist_length)) == NULL) + { + *al = TLS1_AD_INTERNAL_ERROR; + return 0; + } + s->session->tlsext_ecpointformatlist_length = ecpointformatlist_length; + memcpy(s->session->tlsext_ecpointformatlist, sdata, ecpointformatlist_length); +#if 0 + fprintf(stderr,"ssl_parse_serverhello_tlsext s->session->tlsext_ecpointformatlist "); + sdata = s->session->tlsext_ecpointformatlist; + for (i = 0; i < s->session->tlsext_ecpointformatlist_length; i++) + fprintf(stderr,"%i ",*(sdata++)); + fprintf(stderr,"\n"); +#endif + } + data+=size; } +#endif /* OPENSSL_NO_EC */ if (data != d+n) { @@ -383,16 +477,168 @@ int ssl_parse_serverhello_tlsext(SSL *s, unsigned char **p, unsigned char *d, in } } +#ifndef OPENSSL_NO_EC + if (!s->hit && tlsext_ecpointformats == 1) + { + if (s->tlsext_ecpointformatlist) + { + if (s->session->tlsext_ecpointformatlist == NULL) + { + s->session->tlsext_ecpointformatlist_length = s->tlsext_ecpointformatlist_length; + if ((s->session->tlsext_ecpointformatlist = OPENSSL_malloc(s->tlsext_ecpointformatlist_length)) == NULL) + { + *al = TLS1_AD_INTERNAL_ERROR; + return 0; + } + memcpy(s->session->tlsext_ecpointformatlist, s->tlsext_ecpointformatlist, s->tlsext_ecpointformatlist_length); + } + else + { + *al = SSL_AD_DECODE_ERROR; + return 0; + } + } + } +#endif /* OPENSSL_NO_EC */ + *p = data; return 1; } -int ssl_check_tlsext(SSL *s, int is_server) +int ssl_prepare_clienthello_tlsext(SSL *s) + { +#ifndef OPENSSL_NO_EC + /* If we are client and using an elliptic curve cryptography cipher suite, send the point formats we + * support (namely, only uncompressed points). + */ + int using_ecc = 0; + int i; + int algs; + STACK_OF(SSL_CIPHER) *cipher_stack = SSL_get_ciphers(s); + for (i = 0; i < sk_SSL_CIPHER_num(cipher_stack); i++) + { + algs = (sk_SSL_CIPHER_value(cipher_stack, i))->algorithms; + if ((algs & SSL_kECDH) || (algs & SSL_kECDHE) || (algs & SSL_aECDSA)) + { + using_ecc = 1; + break; + } + + } + using_ecc = using_ecc && (s->version == TLS1_VERSION); + if (using_ecc) + { + if ((s->tlsext_ecpointformatlist = OPENSSL_malloc(1)) == NULL) + { + SSLerr(SSL_F_TLS1_PREPARE_CLIENTHELLO_TLSEXT,ERR_R_MALLOC_FAILURE); + return -1; + } + s->tlsext_ecpointformatlist_length = 1; + *s->tlsext_ecpointformatlist = TLSEXT_ECPOINTFORMAT_uncompressed; + } +#endif /* OPENSSL_NO_EC */ + return 1; +} + +int ssl_prepare_serverhello_tlsext(SSL *s) + { +#ifndef OPENSSL_NO_EC + /* If we are server and using an ECC cipher suite, send the point formats we support (namely, only + * uncompressed points) if the client sent us an ECPointsFormat extension. + */ + int i; + int algs = s->s3->tmp.new_cipher->algorithms; + int using_ecc = (algs & SSL_kECDH) || (algs & SSL_kECDHE) || (algs & SSL_aECDSA); + using_ecc = using_ecc && (s->session->tlsext_ecpointformatlist != NULL); + + if (using_ecc) + { + if ((s->tlsext_ecpointformatlist = OPENSSL_malloc(1)) == NULL) + { + SSLerr(SSL_F_TLS1_PREPARE_SERVERHELLO_TLSEXT,ERR_R_MALLOC_FAILURE); + return -1; + } + s->tlsext_ecpointformatlist_length = 1; + *s->tlsext_ecpointformatlist = TLSEXT_ECPOINTFORMAT_uncompressed; + } +#endif /* OPENSSL_NO_EC */ + return 1; +} + +int ssl_check_clienthello_tlsext(SSL *s) { int ret=SSL_TLSEXT_ERR_NOACK; + int al = SSL_AD_UNRECOGNIZED_NAME; + +#ifndef OPENSSL_NO_EC + /* If we are server and using an elliptic curve cyrptography cipher suite, then we don't + * need to check EC point formats since all clients must support uncompressed and it's the + * only thing we support; we just need to copy the data in. We probably ought to check it + * for validity, but we never use it. + */ +#endif + + if (s->ctx != NULL && s->ctx->tlsext_servername_callback != 0) + ret = s->ctx->tlsext_servername_callback(s, &al, s->ctx->tlsext_servername_arg); + else if (s->initial_ctx != NULL && s->initial_ctx->tlsext_servername_callback != 0) + ret = s->initial_ctx->tlsext_servername_callback(s, &al, s->initial_ctx->tlsext_servername_arg); + + switch (ret) { + case SSL_TLSEXT_ERR_ALERT_FATAL: + ssl3_send_alert(s,SSL3_AL_FATAL,al); + return -1; + + case SSL_TLSEXT_ERR_ALERT_WARNING: + ssl3_send_alert(s,SSL3_AL_WARNING,al); + return 1; + + case SSL_TLSEXT_ERR_NOACK: + s->servername_done=0; + default: + return 1; + } +} +int ssl_check_serverhello_tlsext(SSL *s) + { + int ret=SSL_TLSEXT_ERR_NOACK; int al = SSL_AD_UNRECOGNIZED_NAME; +#ifndef OPENSSL_NO_EC + /* If we are client and using an elliptic curve cryptography cipher suite, then server + * must return a an EC point formats lists containing uncompressed. + */ + int algs = s->s3->tmp.new_cipher->algorithms; + if ((s->tlsext_ecpointformatlist != NULL) && (s->tlsext_ecpointformatlist_length > 0) && + ((algs & SSL_kECDH) || (algs & SSL_kECDHE) || (algs & SSL_aECDSA))) + { + /* we are using an ECC cipher */ + int i; + unsigned char *list; + int found_uncompressed = 0; + if ((s->session->tlsext_ecpointformatlist == NULL) || (s->session->tlsext_ecpointformatlist_length <= 0)) + { + SSLerr(SSL_F_TLS1_CHECK_SERVERHELLO_TLSEXT,SSL_R_TLS_INVALID_ECPOINTFORMAT_LIST); + return -1; + } + list = s->session->tlsext_ecpointformatlist; + for (i = 0; i < s->session->tlsext_ecpointformatlist_length; i++) + { + if (*(list++) == TLSEXT_ECPOINTFORMAT_uncompressed) + { + found_uncompressed = 1; + break; + } + } + if (!found_uncompressed) + { + SSLerr(SSL_F_TLS1_CHECK_SERVERHELLO_TLSEXT,SSL_R_TLS_INVALID_ECPOINTFORMAT_LIST); + return -1; + } + } + ret = SSL_TLSEXT_ERR_OK; +#endif /* OPENSSL_NO_EC */ + if (s->ctx != NULL && s->ctx->tlsext_servername_callback != 0) ret = s->ctx->tlsext_servername_callback(s, &al, s->ctx->tlsext_servername_arg); else if (s->initial_ctx != NULL && s->initial_ctx->tlsext_servername_callback != 0) |