unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *p, unsigned char *limit)
{
int extdatalen=0;
unsigned char *ret = p;
/* don't add extensions for SSLv3 unless doing secure renegotiation */
if (s->client_version == SSL3_VERSION
&& !s->s3->send_connection_binding)
return p;
ret+=2;
if (ret>=limit) return NULL; /* this really never occurs, but ... */
if (s->tlsext_hostname != NULL)
{
/* Add TLS extension servername to the Client Hello message */
unsigned long size_str;
long lenmax;
/* check for enough space.
4 for the servername type and entension length
2 for servernamelist length
1 for the hostname type
2 for hostname length
+ hostname length
*/
if ((lenmax = limit - ret - 9) < 0
|| (size_str = strlen(s->tlsext_hostname)) > (unsigned long)lenmax)
return NULL;
/* extension type and length */
s2n(TLSEXT_TYPE_server_name,ret);
s2n(size_str+5,ret);
/* length of servername list */
s2n(size_str+3,ret);
/* hostname type, length and hostname */
*(ret++) = (unsigned char) TLSEXT_NAMETYPE_host_name;
s2n(size_str,ret);
memcpy(ret, s->tlsext_hostname, size_str);
ret+=size_str;
}
/* Add RI if renegotiating */
if (s->new_session)
{
int el;
if(!ssl_add_clienthello_renegotiate_ext(s, 0, &el, 0))
{
SSLerr(SSL_F_SSL_ADD_CLIENTHELLO_TLSEXT, ERR_R_INTERNAL_ERROR);
return NULL;
}
if((limit - p - 4 - el) < 0) return NULL;
s2n(TLSEXT_TYPE_renegotiate,ret);
s2n(el,ret);
if(!ssl_add_clienthello_renegotiate_ext(s, ret, &el, el))
{
SSLerr(SSL_F_SSL_ADD_CLIENTHELLO_TLSEXT, ERR_R_INTERNAL_ERROR);
return NULL;
}
ret += el;
}
if (!(SSL_get_options(s) & SSL_OP_NO_TICKET))
{
int ticklen;
if (!s->new_session && s->session && s->session->tlsext_tick)
ticklen = s->session->tlsext_ticklen;
else
ticklen = 0;
/* Check for enough room 2 for extension type, 2 for len
* rest for ticket
*/
if (limit - ret - 4 - ticklen < 0)
return NULL;
s2n(TLSEXT_TYPE_session_ticket,ret);
s2n(ticklen,ret);
if (ticklen)
{
memcpy(ret, s->session->tlsext_tick, ticklen);
ret += ticklen;
}
}
if (s->tlsext_status_type == TLSEXT_STATUSTYPE_ocsp &&
s->version != DTLS1_VERSION)
{
int i;
long extlen, idlen, itmp;
OCSP_RESPID *id;
idlen = 0;
for (i = 0; i < sk_OCSP_RESPID_num(s->tlsext_ocsp_ids); i++)
{
id = sk_OCSP_RESPID_value(s->tlsext_ocsp_ids, i);
itmp = i2d_OCSP_RESPID(id, NULL);
if (itmp <= 0)
return NULL;
idlen += itmp + 2;
}
if (s->tlsext_ocsp_exts)
{
extlen = i2d_X509_EXTENSIONS(s->tlsext_ocsp_exts, NULL);
if (extlen < 0)
return NULL;
}
else
extlen = 0;
if ((long)(limit - ret - 7 - extlen - idlen) < 0) return NULL;
s2n(TLSEXT_TYPE_status_request, ret);
if (extlen + idlen > 0xFFF0)
return NULL;
s2n(extlen + idlen + 5, ret);
*(ret++) = TLSEXT_STATUSTYPE_ocsp;
s2n(idlen, ret);
for (i = 0; i < sk_OCSP_RESPID_num(s->tlsext_ocsp_ids); i++)
{
/* save position of id len */
unsigned char *q = ret;
id = sk_OCSP_RESPID_value(s->tlsext_ocsp_ids, i);
/* skip over id len */
ret += 2;
itmp = i2d_OCSP_RESPID(id, &ret);
/* write id len */
s2n(itmp, q);
}
s2n(extlen, ret);
if (extlen > 0)
i2d_X509_EXTENSIONS(s->tlsext_ocsp_exts, &ret);
}
if ((extdatalen = ret-p-2)== 0)
return p;
s2n(extdatalen,p);
return ret;
}
unsigned char *ssl_add_clienthello_tlsext(SSL *s, unsigned char *p, unsigned char *limit)
{
int extdatalen=0;
unsigned char *ret = p;
/* don't add extensions for SSLv3 unless doing secure renegotiation */
if (s->client_version == SSL3_VERSION
&& !s->s3->send_connection_binding)
return p;
ret+=2;
if (ret>=limit) return NULL; /* this really never occurs, but ... */
if (s->tlsext_hostname != NULL)
{
/* Add TLS extension servername to the Client Hello message */
unsigned long size_str;
long lenmax;
/* check for enough space.
4 for the servername type and entension length
2 for servernamelist length
1 for the hostname type
2 for hostname length
+ hostname length
*/
if ((lenmax = limit - ret - 9) < 0
|| (size_str = strlen(s->tlsext_hostname)) > (unsigned long)lenmax)
return NULL;
/* extension type and length */
s2n(TLSEXT_TYPE_server_name,ret);
s2n(size_str+5,ret);
/* length of servername list */
s2n(size_str+3,ret);
/* hostname type, length and hostname */
*(ret++) = (unsigned char) TLSEXT_NAMETYPE_host_name;
s2n(size_str,ret);
memcpy(ret, s->tlsext_hostname, size_str);
ret+=size_str;
}
/* Add RI if renegotiating */
if (s->new_session)
{
int el;
if(!ssl_add_clienthello_renegotiate_ext(s, 0, &el, 0))
{
SSLerr(SSL_F_SSL_ADD_CLIENTHELLO_TLSEXT, ERR_R_INTERNAL_ERROR);
return NULL;
}
if((limit - p - 4 - el) < 0) return NULL;
s2n(TLSEXT_TYPE_renegotiate,ret);
s2n(el,ret);
if(!ssl_add_clienthello_renegotiate_ext(s, ret, &el, el))
{
SSLerr(SSL_F_SSL_ADD_CLIENTHELLO_TLSEXT, ERR_R_INTERNAL_ERROR);
return NULL;
}
ret += el;
}
#ifndef OPENSSL_NO_EC
if (s->tlsext_ecpointformatlist != NULL &&
s->version != DTLS1_VERSION)
{
/* Add TLS extension ECPointFormats to the ClientHello message */
long lenmax;
if ((lenmax = limit - ret - 5) < 0) return NULL;
if (s->tlsext_ecpointformatlist_length > (unsigned long)lenmax) return NULL;
if (s->tlsext_ecpointformatlist_length > 255)
{
SSLerr(SSL_F_SSL_ADD_CLIENTHELLO_TLSEXT, ERR_R_INTERNAL_ERROR);
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;
}
if (s->tlsext_ellipticcurvelist != NULL &&
s->version != DTLS1_VERSION)
{
/* Add TLS extension EllipticCurves to the ClientHello message */
long lenmax;
if ((lenmax = limit - ret - 6) < 0) return NULL;
if (s->tlsext_ellipticcurvelist_length > (unsigned long)lenmax) return NULL;
if (s->tlsext_ellipticcurvelist_length > 65532)
{
SSLerr(SSL_F_SSL_ADD_CLIENTHELLO_TLSEXT, ERR_R_INTERNAL_ERROR);
return NULL;
}
s2n(TLSEXT_TYPE_elliptic_curves,ret);
s2n(s->tlsext_ellipticcurvelist_length + 2, ret);
/* NB: draft-ietf-tls-ecc-12.txt uses a one-byte prefix for
* elliptic_curve_list, but the examples use two bytes.
* http://www1.ietf.org/mail-archive/web/tls/current/msg00538.html
* resolves this to two bytes.
*/
s2n(s->tlsext_ellipticcurvelist_length, ret);
memcpy(ret, s->tlsext_ellipticcurvelist, s->tlsext_ellipticcurvelist_length);
ret+=s->tlsext_ellipticcurvelist_length;
}
#endif /* OPENSSL_NO_EC */
if (!(SSL_get_options(s) & SSL_OP_NO_TICKET))
{
int ticklen;
if (!s->new_session && s->session && s->session->tlsext_tick)
ticklen = s->session->tlsext_ticklen;
else if (s->session && s->tlsext_session_ticket &&
s->tlsext_session_ticket->data)
{
ticklen = s->tlsext_session_ticket->length;
s->session->tlsext_tick = OPENSSL_malloc(ticklen);
if (!s->session->tlsext_tick)
return NULL;
memcpy(s->session->tlsext_tick,
s->tlsext_session_ticket->data,
ticklen);
s->session->tlsext_ticklen = ticklen;
}
else
ticklen = 0;
if (ticklen == 0 && s->tlsext_session_ticket &&
s->tlsext_session_ticket->data == NULL)
goto skip_ext;
/* Check for enough room 2 for extension type, 2 for len
* rest for ticket
*/
if ((long)(limit - ret - 4 - ticklen) < 0) return NULL;
s2n(TLSEXT_TYPE_session_ticket,ret);
s2n(ticklen,ret);
if (ticklen)
{
memcpy(ret, s->session->tlsext_tick, ticklen);
ret += ticklen;
}
}
skip_ext:
#ifdef TLSEXT_TYPE_opaque_prf_input
if (s->s3->client_opaque_prf_input != NULL &&
s->version != DTLS1_VERSION)
{
size_t col = s->s3->client_opaque_prf_input_len;
if ((long)(limit - ret - 6 - col < 0))
return NULL;
if (col > 0xFFFD) /* can't happen */
return NULL;
s2n(TLSEXT_TYPE_opaque_prf_input, ret);
s2n(col + 2, ret);
s2n(col, ret);
memcpy(ret, s->s3->client_opaque_prf_input, col);
ret += col;
}
#endif
if (s->tlsext_status_type == TLSEXT_STATUSTYPE_ocsp &&
s->version != DTLS1_VERSION)
{
int i;
long extlen, idlen, itmp;
OCSP_RESPID *id;
idlen = 0;
for (i = 0; i < sk_OCSP_RESPID_num(s->tlsext_ocsp_ids); i++)
{
id = sk_OCSP_RESPID_value(s->tlsext_ocsp_ids, i);
itmp = i2d_OCSP_RESPID(id, NULL);
if (itmp <= 0)
return NULL;
idlen += itmp + 2;
}
if (s->tlsext_ocsp_exts)
{
extlen = i2d_X509_EXTENSIONS(s->tlsext_ocsp_exts, NULL);
if (extlen < 0)
return NULL;
}
else
extlen = 0;
if ((long)(limit - ret - 7 - extlen - idlen) < 0) return NULL;
s2n(TLSEXT_TYPE_status_request, ret);
if (extlen + idlen > 0xFFF0)
return NULL;
s2n(extlen + idlen + 5, ret);
*(ret++) = TLSEXT_STATUSTYPE_ocsp;
s2n(idlen, ret);
for (i = 0; i < sk_OCSP_RESPID_num(s->tlsext_ocsp_ids); i++)
{
/* save position of id len */
unsigned char *q = ret;
id = sk_OCSP_RESPID_value(s->tlsext_ocsp_ids, i);
/* skip over id len */
ret += 2;
itmp = i2d_OCSP_RESPID(id, &ret);
/* write id len */
s2n(itmp, q);
}
s2n(extlen, ret);
if (extlen > 0)
i2d_X509_EXTENSIONS(s->tlsext_ocsp_exts, &ret);
}
if ((extdatalen = ret-p-2)== 0)
return p;
s2n(extdatalen,p);
return ret;
}