/**
* Prepare push options, based on local options and available peer info.
*
* @param options Connection options
* @param tls_multi TLS state structure for the current tunnel
*
* @return true on success, false on failure.
*/
static bool
prepare_push_reply (struct options *o, struct tls_multi *tls_multi)
{
const char *optstr = NULL;
const char * const peer_info = tls_multi->peer_info;
/* Send peer-id if client supports it */
optstr = peer_info ? strstr(peer_info, "IV_PROTO=") : NULL;
if (optstr)
{
int proto = 0;
int r = sscanf(optstr, "IV_PROTO=%d", &proto);
if ((r == 1) && (proto >= 2))
{
push_option_fmt(o, M_USAGE, "peer-id %d", tls_multi->peer_id);
}
}
/* Push cipher if client supports Negotiable Crypto Parameters */
if (tls_peer_info_ncp_ver (peer_info) >= 2 && o->ncp_enabled)
{
/* Push the first cipher from --ncp-ciphers to the client.
* TODO: actual negotiation, instead of server dictatorship. */
char *push_cipher = string_alloc(o->ncp_ciphers, &o->gc);
o->ciphername = strtok (push_cipher, ":");
push_option_fmt(o, M_USAGE, "cipher %s", o->ciphername);
}
return true;
}
/**
* Prepare push options, based on local options and available peer info.
*
* @param context context structure storing data for VPN tunnel
* @param gc gc arena for allocating push options
* @param push_list push list to where options are added
*
* @return true on success, false on failure.
*/
static bool
prepare_push_reply(struct context *c, struct gc_arena *gc,
struct push_list *push_list)
{
const char *optstr = NULL;
struct tls_multi *tls_multi = c->c2.tls_multi;
const char *const peer_info = tls_multi->peer_info;
struct options *o = &c->options;
/* ipv6 */
if (c->c2.push_ifconfig_ipv6_defined && !o->push_ifconfig_ipv6_blocked)
{
push_option_fmt(gc, push_list, M_USAGE, "ifconfig-ipv6 %s/%d %s",
print_in6_addr(c->c2.push_ifconfig_ipv6_local, 0, gc),
c->c2.push_ifconfig_ipv6_netbits,
print_in6_addr(c->c2.push_ifconfig_ipv6_remote,
0, gc));
}
/* ipv4 */
if (c->c2.push_ifconfig_defined && c->c2.push_ifconfig_local
&& c->c2.push_ifconfig_remote_netmask
&& !o->push_ifconfig_ipv4_blocked)
{
in_addr_t ifconfig_local = c->c2.push_ifconfig_local;
if (c->c2.push_ifconfig_local_alias)
{
ifconfig_local = c->c2.push_ifconfig_local_alias;
}
push_option_fmt(gc, push_list, M_USAGE, "ifconfig %s %s",
print_in_addr_t(ifconfig_local, 0, gc),
print_in_addr_t(c->c2.push_ifconfig_remote_netmask,
0, gc));
}
/* Send peer-id if client supports it */
optstr = peer_info ? strstr(peer_info, "IV_PROTO=") : NULL;
if (optstr)
{
int proto = 0;
int r = sscanf(optstr, "IV_PROTO=%d", &proto);
if ((r == 1) && (proto >= 2))
{
push_option_fmt(gc, push_list, M_USAGE, "peer-id %d",
tls_multi->peer_id);
tls_multi->use_peer_id = true;
}
}
/* Push cipher if client supports Negotiable Crypto Parameters */
if (tls_peer_info_ncp_ver(peer_info) >= 2 && o->ncp_enabled)
{
/* if we have already created our key, we cannot *change* our own
* cipher -> so log the fact and push the "what we have now" cipher
* (so the client is always told what we expect it to use)
*/
const struct tls_session *session = &tls_multi->session[TM_ACTIVE];
if (session->key[KS_PRIMARY].crypto_options.key_ctx_bi.initialized)
{
msg( M_INFO, "PUSH: client wants to negotiate cipher (NCP), but "
"server has already generated data channel keys, "
"re-sending previously negotiated cipher '%s'",
o->ciphername );
}
else
{
/* Push the first cipher from --ncp-ciphers to the client.
* TODO: actual negotiation, instead of server dictatorship. */
char *push_cipher = string_alloc(o->ncp_ciphers, &o->gc);
o->ciphername = strtok(push_cipher, ":");
}
push_option_fmt(gc, push_list, M_USAGE, "cipher %s", o->ciphername);
}
else if (o->ncp_enabled)
{
tls_poor_mans_ncp(o, tls_multi->remote_ciphername);
}
/* If server uses --auth-gen-token and we have an auth token
* to send to the client
*/
if (false == tls_multi->auth_token_sent && NULL != tls_multi->auth_token)
{
push_option_fmt(gc, push_list, M_USAGE,
"auth-token %s", tls_multi->auth_token);
tls_multi->auth_token_sent = true;
}
return true;
}
