/* Create a new connection context. */
static ConnContext * new_context(const char * user, const char * accountname,
const char * protocol)
{
ConnContext * context;
OtrlSMState *smstate;
context = malloc(sizeof(*context));
assert(context != NULL);
context->username = strdup(user);
context->accountname = strdup(accountname);
context->protocol = strdup(protocol);
context->fragment = NULL;
context->fragment_len = 0;
context->fragment_n = 0;
context->fragment_k = 0;
context->msgstate = OTRL_MSGSTATE_PLAINTEXT;
otrl_auth_new(&(context->auth));
smstate = malloc(sizeof(OtrlSMState));
assert(smstate != NULL);
otrl_sm_state_new(smstate);
context->smstate = smstate;
context->fingerprint_root.fingerprint = NULL;
context->fingerprint_root.context = context;
context->fingerprint_root.next = NULL;
context->fingerprint_root.tous = NULL;
context->active_fingerprint = NULL;
context->their_keyid = 0;
context->their_y = NULL;
context->their_old_y = NULL;
context->our_keyid = 0;
context->our_dh_key.groupid = 0;
context->our_dh_key.priv = NULL;
context->our_dh_key.pub = NULL;
context->our_old_dh_key.groupid = 0;
context->our_old_dh_key.priv = NULL;
context->our_old_dh_key.pub = NULL;
otrl_dh_session_blank(&(context->sesskeys[0][0]));
otrl_dh_session_blank(&(context->sesskeys[0][1]));
otrl_dh_session_blank(&(context->sesskeys[1][0]));
otrl_dh_session_blank(&(context->sesskeys[1][1]));
memset(context->sessionid, 0, 20);
context->sessionid_len = 0;
context->protocol_version = 0;
context->numsavedkeys = 0;
context->preshared_secret = NULL;
context->preshared_secret_len = 0;
context->saved_mac_keys = NULL;
context->generation = 0;
context->lastsent = 0;
context->lastmessage = NULL;
context->may_retransmit = 0;
context->otr_offer = OFFER_NOT;
context->app_data = NULL;
context->app_data_free = NULL;
context->next = NULL;
return context;
}
/* Make a new DH key for us, and rotate old old ones. Be sure to keep
* the sesskeys array in sync. */
static gcry_error_t rotate_dh_keys(ConnContext *context)
{
gcry_error_t err;
/* Rotate the keypair */
otrl_dh_keypair_free(&(context->context_priv->our_old_dh_key));
memmove(&(context->context_priv->our_old_dh_key),
&(context->context_priv->our_dh_key),
sizeof(DH_keypair));
/* Rotate the session keys */
err = reveal_macs(context, &(context->context_priv->sesskeys[1][0]),
&(context->context_priv->sesskeys[1][1]));
if (err) return err;
otrl_dh_session_free(&(context->context_priv->sesskeys[1][0]));
otrl_dh_session_free(&(context->context_priv->sesskeys[1][1]));
memmove(&(context->context_priv->sesskeys[1][0]),
&(context->context_priv->sesskeys[0][0]),
sizeof(DH_sesskeys));
memmove(&(context->context_priv->sesskeys[1][1]),
&(context->context_priv->sesskeys[0][1]),
sizeof(DH_sesskeys));
/* Create a new DH key */
otrl_dh_gen_keypair(DH1536_GROUP_ID, &(context->context_priv->our_dh_key));
context->context_priv->our_keyid++;
/* Make the session keys */
if (context->context_priv->their_y) {
err = otrl_dh_session(&(context->context_priv->sesskeys[0][0]),
&(context->context_priv->our_dh_key),
context->context_priv->their_y);
if (err) return err;
} else {
otrl_dh_session_blank(&(context->context_priv->sesskeys[0][0]));
}
if (context->context_priv->their_old_y) {
err = otrl_dh_session(&(context->context_priv->sesskeys[0][1]),
&(context->context_priv->our_dh_key),
context->context_priv->their_old_y);
if (err) return err;
} else {
otrl_dh_session_blank(&(context->context_priv->sesskeys[0][1]));
}
return gcry_error(GPG_ERR_NO_ERROR);
}
