void send_asymmetric_encrypted(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_public_key(key))
{
struct item *pay = network_receive(net_stat);
//@ assert item(pay, ?p, pub);
struct item *enc = asymmetric_encryption(key, pay);
//@ assert item(enc, ?e, pub);
//@ open proof_obligations(pub);
/*@ if (col)
{
assert is_public_collision(?proof, pub);
proof(e);
}
else
{
assert is_public_asymmetric_encrypted(?proof, pub);
proof(e);
}
@*/
//@ close proof_obligations(pub);
network_send(net_stat, enc);
item_free(enc);
item_free(pay);
}
item_free(key);
}
struct item *asymmetric_authenticated_encryption(char recipient,
struct item *public_key,
struct item *private_key,
struct item *payload)
/*@ requires [?f]world(?pub) &*&
generated_values(?principal1, ?count1) &*&
item(public_key, ?pub_k, pub) &*&
pub_k == public_key_item(?principal2, ?count2) &*&
item(private_key, ?priv_k, pub) &*&
priv_k == private_key_item(?principal3, ?count3) &*&
item(payload, ?pay, pub); @*/
/*@ ensures [f]world(pub) &*&
generated_values(principal1, count1 + 2) &*&
item(public_key, pub_k, pub) &*&
item(private_key, priv_k, pub) &*&
item(payload, pay, pub) &*&
item(result, ?msg, pub) &*&
collision_in_run() ?
true
:
msg == pair_item(?enc, ?sig) &*&
enc == asymmetric_encrypted_item(principal2, count2,
some(pay), _) &*&
sig == asymmetric_signature_item(principal3, count3,
some(?msg_id), _) &*&
msg_id == pair_item(data_item(cons(recipient, nil)),
hash_item(some(enc))); @*/
{
struct item* encrypted = asymmetric_encryption(public_key, payload);
struct item* hash = create_hash(encrypted);
struct item* rcp = create_data_item_from_char(recipient);
struct item* msg_id = create_pair(rcp, hash);
struct item* signature = asymmetric_signature(private_key, msg_id);
struct item* result = create_pair(encrypted, signature);
item_free(encrypted);
item_free(hash);
item_free(rcp);
item_free(msg_id);
item_free(signature);
return result;
}
