Encrypted payment IDs

A payment ID may be encrypted using the tx secret key and the
receiver's public view key. The receiver can decrypt it with
the tx public key and the receiver's secret view key.

Using integrated addresses now cause the payment IDs to be
encrypted. Payment IDs used manually are not encrypted by default,
but can be encrypted using the new 'encrypt_payment_id' field
in the transfer and transfer_split RPC calls. It is not possible
to use an encrypted payment ID by specifying a manual simplewallet
transfer/transfer_new command, though this is just a limitation
due to input parsing.

1 files changed, 20 insertions, 2 deletions

diff --git a/src/wallet/wallet2.cpp b/src/wallet/wallet2.cpp
index 5b7b19520..12db73423 100644
--- a/src/wallet/wallet2.cpp
+++ b/src/wallet/wallet2.cpp
@@ -150,6 +150,7 @@ void wallet2::process_new_transaction(const cryptonote::transaction& tx, uint64_
   process_unconfirmed(tx);
   std::vector<size_t> outs;
   uint64_t tx_money_got_in_outs = 0;
+  crypto::public_key tx_pub_key = null_pkey;
 
   std::vector<tx_extra_field> tx_extra_fields;
   if(!parse_tx_extra(tx.extra, tx_extra_fields))
@@ -170,7 +171,7 @@ void wallet2::process_new_transaction(const cryptonote::transaction& tx, uint64_
       return;
     }
 
-    crypto::public_key tx_pub_key = pub_key_field.pub_key;
+    tx_pub_key = pub_key_field.pub_key;
     bool r = lookup_acc_outs(m_account.get_keys(), tx, tx_pub_key, outs, tx_money_got_in_outs);
     THROW_WALLET_EXCEPTION_IF(!r, error::acc_outs_lookup_error, tx, tx_pub_key, m_account.get_keys());
 
@@ -236,9 +237,26 @@ void wallet2::process_new_transaction(const cryptonote::transaction& tx, uint64_
   crypto::hash payment_id = null_hash;
   if (find_tx_extra_field_by_type(tx_extra_fields, extra_nonce))
   {
-    if(get_payment_id_from_tx_extra_nonce(extra_nonce.nonce, payment_id))
+    bool encrypted;
+    if(get_payment_id_from_tx_extra_nonce(extra_nonce.nonce, payment_id, encrypted) && encrypted)
     {
       // We got a payment ID to go with this tx
+      LOG_PRINT_L2("Found encrypted payment ID: " << payment_id);
+      if (tx_pub_key != null_pkey)
+      {
+        if (!decrypt_payment_id(payment_id, tx_pub_key, m_account.get_keys().m_view_secret_key))
+        {
+          LOG_PRINT_L0("Failed to decrypt payment ID: " << payment_id);
+        }
+        else
+        {
+          LOG_PRINT_L2("Decrypted payment ID: " << payment_id);
+        }
+      }
+      else
+      {
+        LOG_PRINT_L1("No public key found in tx, unable to decrypt payment id");
+      }
     }
   }
   uint64_t received = (tx_money_spent_in_ins < tx_money_got_in_outs) ? tx_money_got_in_outs - tx_money_spent_in_ins : 0;