void check_is_asymmetric_encrypted(struct item *item)
//@ requires [?f]world(?pub, ?key_clsfy) &*& item(item, ?i, pub);
/*@ ensures [f]world(pub, key_clsfy) &*& item(item, i, pub) &*&
i == asymmetric_encrypted_item(_, _, _, _); @*/
{
if (!is_asymmetric_encrypted(item))
abort_crypto_lib("Presented item is not an asymmetric encrypted item");
}
void send_asymmetric_decrypted(struct network_status *net_stat, struct keypair *keypair)
/*@ requires [?f0]world(?pub, ?key_clsfy) &*&
keypair(keypair, ?attacker_id, ?id, ?info, pub) &*&
proof_obligations(pub) &*&
network_status(net_stat) &*&
principal(attacker_id, ?count1) &*&
true == bad(attacker_id); @*/
/*@ ensures [f0]world(pub, key_clsfy) &*&
keypair(keypair, attacker_id, id, info, pub) &*&
proof_obligations(pub) &*&
network_status(net_stat) &*&
principal(attacker_id, ?count2); @*/
{
struct item *key = network_receive(net_stat);
//@ assert item(key, ?k, pub);
if (is_private_key(key))
{
//@ assert k == private_key_item(?principal2, ?count2);
struct item *enc = network_receive(net_stat);
//@ assert item(enc, ?e, pub);
if (is_asymmetric_encrypted(enc))
{
//@ assert e == asymmetric_encrypted_item(?principal3, ?count3, ?pay, ?ent);
char tag;
//@ close chars(&tag, 1, _);
random_buffer_(&tag, 1);
//@ open chars(&tag, 1, _);
if (tag == TAG_DATA || tag == TAG_PAIR ||
tag == TAG_NONCE || tag == TAG_HASH ||
tag == TAG_SYMMETRIC_KEY || tag == TAG_PUBLIC_KEY ||
tag == TAG_PRIVATE_KEY || tag == TAG_HMAC ||
tag == TAG_SYMMETRIC_ENC || tag == TAG_ASYMMETRIC_ENC ||
tag == TAG_ASYMMETRIC_SIG)
{
struct item *dec = asymmetric_decryption(key, enc, tag);
//@ assert item(dec, ?d, pub);
//@ open proof_obligations(pub);
/*@ if (col)
{
assert [_]pub(d);
}
else if (principal2 == principal3 && count2 == count3)
{
assert pay == some(d);
assert is_public_asymmetric_decrypted(?proof, pub);
proof(e);
}
else
{
assert [_]pub(d);
}
@*/
network_send(net_stat, dec);
//@ close proof_obligations(pub);
item_free(dec);
}
}
item_free(enc);
}
item_free(key);
}
