From cadedbcbdf91062ce98cd8824cb008c49d7a62cf Mon Sep 17 00:00:00 2001
From: 10gic <github10gic@proton.me>
Date: Fri, 6 Dec 2024 22:55:56 +0800
Subject: [PATCH 1/7] Support compiling a transaction with partial signatures
 (#4143)

Fix issue #4142
---
 .../chains/tw_solana/src/modules/tx_signer.rs |  7 ---
 .../tests/chains/solana/solana_compile.rs     | 53 +++++++++++++++++++
 2 files changed, 53 insertions(+), 7 deletions(-)

diff --git a/rust/chains/tw_solana/src/modules/tx_signer.rs b/rust/chains/tw_solana/src/modules/tx_signer.rs
index 5fb421e6876..754fa372efe 100644
--- a/rust/chains/tw_solana/src/modules/tx_signer.rs
+++ b/rust/chains/tw_solana/src/modules/tx_signer.rs
@@ -44,13 +44,6 @@ impl TxSigner {
     ) -> SigningResult<versioned::VersionedTransaction> {
         let mut tx = versioned::VersionedTransaction::unsigned(unsigned_msg);
 
-        let actual_signatures = key_signs.len();
-        let expected_signatures = tx.message.num_required_signatures();
-        if actual_signatures != expected_signatures {
-            return SigningError::err(SigningErrorType::Error_signatures_count)
-                .with_context(|| format!("Expected '{expected_signatures}' signatures, provided '{actual_signatures}'"));
-        }
-
         for (signing_pubkey, ed25519_signature) in key_signs {
             // Find an index of the corresponding account.
             let account_index = tx
diff --git a/rust/tw_tests/tests/chains/solana/solana_compile.rs b/rust/tw_tests/tests/chains/solana/solana_compile.rs
index 592d5bee322..d57c136f067 100644
--- a/rust/tw_tests/tests/chains/solana/solana_compile.rs
+++ b/rust/tw_tests/tests/chains/solana/solana_compile.rs
@@ -3,8 +3,10 @@
 // Copyright © 2017 Trust Wallet.
 
 use tw_any_coin::test_utils::sign_utils::{CompilerHelper, PreImageHelper};
+use tw_any_coin::test_utils::transaction_decode_utils::TransactionDecoderHelper;
 use tw_coin_registry::coin_type::CoinType;
 use tw_encoding::base58::{self, Alphabet};
+use tw_encoding::base64::{self, STANDARD};
 use tw_encoding::hex::{DecodeHex, ToHex};
 use tw_proto::Common::Proto::SigningError;
 use tw_proto::Solana::Proto::{self, mod_SigningInput::OneOftransaction_type as TransactionType};
@@ -421,3 +423,54 @@ fn test_solana_compile_transfer_with_fake_signature() {
     let output = compiler.compile(CoinType::Solana, &input, vec![signature], vec![public_key]);
     assert_eq!(output.error, SigningError::Error_signing);
 }
+
+#[test]
+fn test_solana_compile_with_partial_signature() {
+    // The following is an unsigned transaction generated by the Jito Staking DApp.
+    // This transaction requires two signatures; only the first one will be provided by the user.
+    // The DApp will add the second signature before submitting the transaction to Solana network.
+    let encoded_unsigned_tx = base64::decode("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", STANDARD).unwrap();
+
+    // Step 1: Decode the transaction, get the raw message, and prepare the signing input
+    let mut decoder = TransactionDecoderHelper::<Proto::DecodingTransactionOutput>::default();
+    let output = decoder.decode(CoinType::Solana, encoded_unsigned_tx);
+    assert_eq!(output.error, SigningError::OK);
+
+    let input = Proto::SigningInput {
+        raw_message: output.transaction,
+        ..Proto::SigningInput::default()
+    };
+
+    // Step 2: Simulate signature (the first signature), normally obtained from signature server.
+    let signature1 = "daf56b31e3a97504bb5adb4c64709cdd8240700935d9e1cae9a05ab032de04b469cc1e02587f9c6d7e57192e4f9c77117897a85d15900730d90a7f55debf690a".decode_hex().unwrap();
+    let public_key1 = "a32b7552671b22997c330c53ac91ea68d04729d0cbdd71e48934416e52ec78db"
+        .decode_hex()
+        .unwrap();
+
+    // Step 3: Compile the transaction with partial signature
+    let mut compiler = CompilerHelper::<Proto::SigningOutput>::default();
+    let output = compiler.compile(
+        CoinType::Solana,
+        &input,
+        vec![signature1],
+        vec![public_key1],
+    );
+    assert_eq!(output.error, SigningError::OK);
+    assert_eq!(output.encoded, "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");
+
+    // Step 4: Return the compiled transaction with partial signature to the DApp, which will then complete the remaining signatures.
+    let mut tx_with_partial_signature =
+        base58::decode(output.encoded.as_ref(), Alphabet::Bitcoin).unwrap();
+    // The following is the signature (the second signature) generated by the DApp.
+    let signature_generated_by_dapp = "c3207d277754a1a872bdc910136e917f9e902f025e493f0c1bf3d5b4512fffe03b250e86e4e68e20e96ab09beb24d7706ae338a2c5d11fbb23d779ae5b8c0701".decode_hex().unwrap();
+    // The following is a simple code to simulate the process of the DApp filling in the second signature.
+    let second_signature_offset = 1 + 64;
+    let second_signature_length = 64;
+    tx_with_partial_signature
+        [second_signature_offset..(second_signature_offset + second_signature_length)]
+        .copy_from_slice(&signature_generated_by_dapp);
+
+    let full_signed_tx = base64::encode(&tx_with_partial_signature, STANDARD);
+    // Successfully broadcasted: https://solscan.io/tx/5NuXtYpE58FbtCfEzgk2cTHZgEdNF69Z76bd8TQhBgmEN1RC98DNGNiWhvp1VSDMPudCgpE3z8jD7BNRuBztUbpM
+    assert_eq!(full_signed_tx, "Atr1azHjqXUEu1rbTGRwnN2CQHAJNdnhyumgWrAy3gS0acweAlh/nG1+VxkuT5x3EXiXqF0VkAcw2Qp/Vd6/aQrDIH0nd1ShqHK9yRATbpF/npAvAl5JPwwb89W0US//4DslDobk5o4g6Wqwm+sk13Bq4ziixdEfuyPXea5bjAcBAgAGDqMrdVJnGyKZfDMMU6yR6mjQRynQy91x5Ik0QW5S7HjblEDFOjfYkcjeiZdpl9opTtGz1XgRDjyGqc4Z5VKuBHI5lg1U5Wnl5tFnrGEI9Y2rG1BNC7tYK5PXpURkpupeap6naP7fZEyKrpuOIYit0GvFUPv3Fsgiuc5jx3g9lS4fsU4N5V6fuoY5br/VSM/4ySAR6se3W6qbLZxqhvWhcUEJ5qP+7PmQMuHB32uXItyzY057jjRAk2vDSwzByOtSH/zRQemDLK8QrZF0lcoPJxtbKTzUcCfqc3AH7UDrOaC9BIo+CMO0lb4X9FQn2JvsW4DH4mlcGGTXZ0PbOb7TRtYAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAFTlniTAUaihSnsel5fw4Szfp0kCFmUxlaalEqbxZmArjJclj04kifG7PRApFI4NgwtaE5na/xCEBI572Nvp+FkDBkZv5SEXMv/srbpyw5vnvIzlu8X3EmssQ5s6QAAAAAaBTtTK9ooXRnL9rIYDGmPoTqFe+h1EtyKT9tvbABZQBt324ddloZPZy+FGzut5rBy0he1fWzeROoz1hX7/AKnLHFG8r27UznARMamsTdStWltOfL+TLpgyxe4Hfqm8xQYIAgABDAIAAACghgEAAAAAAAoGAAIABggNAQEMCgcJAwECBQIGCA0JDqCGAQAAAAAACwAFAkANAwALAAkDgDgBAAAAAAAIAgAEDAIAAAC0/gAAAAAAAA==")
+}

From eb408ea706f4b64f6930af95f1ed2208f36da01d Mon Sep 17 00:00:00 2001
From: Sergei Boiko <127754187+satoshiotomakan@users.noreply.github.com>
Date: Fri, 6 Dec 2024 21:56:35 +0700
Subject: [PATCH 2/7] [BRC20]: Fix bug when revealing BRC20 with extra P2TR
 (#4152)

---
 .../tw_utxo/src/modules/sighash_computer.rs   | 14 ++--
 .../chains/bitcoin/bitcoin_sign/brc20.rs      | 74 +++++++++++++++++++
 2 files changed, 82 insertions(+), 6 deletions(-)

diff --git a/rust/frameworks/tw_utxo/src/modules/sighash_computer.rs b/rust/frameworks/tw_utxo/src/modules/sighash_computer.rs
index 0bcfb626960..f2ee8880590 100644
--- a/rust/frameworks/tw_utxo/src/modules/sighash_computer.rs
+++ b/rust/frameworks/tw_utxo/src/modules/sighash_computer.rs
@@ -60,11 +60,11 @@ where
             .input_args()
             .iter()
             .enumerate()
-            .map(|(input_index, utxo)| {
+            .map(|(signing_input_index, utxo)| {
                 let signing_method = utxo.signing_method;
 
                 let utxo_args = UtxoPreimageArgs {
-                    input_index,
+                    input_index: signing_input_index,
                     script_pubkey: utxo.script_pubkey.clone(),
                     amount: utxo.amount,
                     // TODO move `leaf_hash_code_separator` to `UtxoTaprootPreimageArgs`.
@@ -90,12 +90,14 @@ where
                         let tr_spent_script_pubkeys: Vec<Script> = unsigned_tx
                             .input_args()
                             .iter()
-                            .map(|utxo| {
-                                if utxo.signing_method == SigningMethod::Taproot {
-                                    // Taproot UTXOs scriptPubkeys should be signed as is.
+                            .enumerate()
+                            .map(|(i, utxo)| {
+                                if i == signing_input_index {
+                                    // Use the scriptPubkey required to spend this UTXO.
                                     utxo.script_pubkey.clone()
                                 } else {
-                                    // Use the original scriptPubkey declared in the unspent output.
+                                    // Use the original scriptPubkey declared in the unspent output for other UTXOs
+                                    // (different from that we sign at this iteration).
                                     utxo.prevout_script_pubkey.clone()
                                 }
                             })
diff --git a/rust/tw_tests/tests/chains/bitcoin/bitcoin_sign/brc20.rs b/rust/tw_tests/tests/chains/bitcoin/bitcoin_sign/brc20.rs
index 5836744205a..b81777faef6 100644
--- a/rust/tw_tests/tests/chains/bitcoin/bitcoin_sign/brc20.rs
+++ b/rust/tw_tests/tests/chains/bitcoin/bitcoin_sign/brc20.rs
@@ -196,3 +196,77 @@ fn test_bitcoin_sign_brc20_transfer() {
             fee: 3000,
         });
 }
+
+/// Fixes `{"error":"-26: non-mandatory-script-verify-flag (Invalid Schnorr signature)"}` error.
+#[test]
+fn test_bitcoin_sign_brc20_reveal_with_extra_p2tr_input() {
+    // bc1puq428nh4eynlqph8gynwdtqg4je0hc03gp2ptgsf4c5ylxz0ll2sd34gk7
+    let alice_pk_bytes = "8efa479919269076eb331c304fff187b9d7aa60d1f6cd3d6b12a151a52f22582"
+        .decode_hex()
+        .unwrap();
+    let alice_private_key = schnorr::PrivateKey::try_from(alice_pk_bytes.as_slice()).unwrap();
+    let alice_pubkey = alice_private_key.public().compressed();
+    let my_address = "bc1puq428nh4eynlqph8gynwdtqg4je0hc03gp2ptgsf4c5ylxz0ll2sd34gk7";
+
+    let commit_txid = "164b459a49c5e3a817028df7f4545585874feff3985e48d6ff6792989a4823a8";
+    let commit_utxo = Proto::Input {
+        out_point: input::out_point(commit_txid, 0),
+        value: 546,
+        sighash_type: SIGHASH_ALL,
+        claiming_script: input::brc20_inscribe(alice_pubkey.to_vec(), "duna", "0.001"),
+        ..Default::default()
+    };
+
+    // Extra P2TR UTXO is used to cover transaction fee.
+    let p2tr_utxo = "164b459a49c5e3a817028df7f4545585874feff3985e48d6ff6792989a4823a8";
+    let extra_p2tr = Proto::Input {
+        out_point: input::out_point(p2tr_utxo, 1),
+        value: 11_210,
+        sighash_type: SIGHASH_ALL,
+        claiming_script: input::receiver_address(my_address),
+        ..Default::default()
+    };
+
+    let out1 = Proto::Output {
+        value: 546,
+        to_recipient: output::to_address(my_address),
+    };
+    let change_output = Proto::Output {
+        value: 0,
+        to_recipient: output::to_address(my_address),
+    };
+
+    let builder = Proto::TransactionBuilder {
+        version: Proto::TransactionVersion::V2,
+        inputs: vec![commit_utxo, extra_p2tr],
+        outputs: vec![out1],
+        change_output: Some(change_output),
+        input_selector: Proto::InputSelector::UseAll,
+        dust_policy: dust_threshold(DUST),
+        fee_per_vb: 9,
+        ..Default::default()
+    };
+
+    let signing = Proto::SigningInput {
+        private_keys: vec![alice_pk_bytes.into()],
+        chain_info: btc_info(),
+        // We enable deterministic Schnorr signatures here
+        dangerous_use_fixed_schnorr_rng: true,
+        transaction: TransactionOneof::builder(builder),
+        ..Default::default()
+    };
+
+    // https://www.blockchain.com/explorer/transactions/btc/113dfc827e4535dccc6aa7fcff5482b4de0fb2ab70f52c44c12c12bca3be5847
+    sign::BitcoinSignHelper::new(&signing)
+        .coin(CoinType::Bitcoin)
+        .sign(sign::Expected {
+            encoded: "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",
+            txid: "113dfc827e4535dccc6aa7fcff5482b4de0fb2ab70f52c44c12c12bca3be5847",
+            inputs: vec![546, 11_210],
+            outputs: vec![546, 9_005],
+            // `vsize` is different from the estimated value due to the signatures der serialization.
+            vsize: 244,
+            weight: 975,
+            fee: 2_205,
+        });
+}

From 08e496a1d3575423143b18e5397c51037c772e34 Mon Sep 17 00:00:00 2001
From: Robert Gabriel Jakabosky <rjakabosky+github@neoawareness.com>
Date: Fri, 6 Dec 2024 22:57:15 +0800
Subject: [PATCH 3/7] Fix custom call indice support in BondAndNominate and
 ChillAndUnbond batches. (#4109)

---
 src/Polkadot/Extrinsic.cpp            |  10 ++-
 src/proto/Polkadot.proto              |  12 +++
 tests/chains/Polkadot/SignerTests.cpp | 106 ++++++++++++++++++++++++++
 3 files changed, 127 insertions(+), 1 deletion(-)

diff --git a/src/Polkadot/Extrinsic.cpp b/src/Polkadot/Extrinsic.cpp
index dcd0b31a308..7cc3540c3a5 100644
--- a/src/Polkadot/Extrinsic.cpp
+++ b/src/Polkadot/Extrinsic.cpp
@@ -210,6 +210,8 @@ Data Extrinsic::encodeStakingCall(const Proto::Staking& staking) const {
             bond->set_controller(staking.bond_and_nominate().controller());
             bond->set_value(staking.bond_and_nominate().value());
             bond->set_reward_destination(staking.bond_and_nominate().reward_destination());
+            auto callIndices = staking.bond_and_nominate().bond_call_indices();
+            bond->mutable_call_indices()->CopyFrom(callIndices);
             // recursive call
             call1 = encodeStakingCall(staking1);
         }
@@ -222,6 +224,8 @@ Data Extrinsic::encodeStakingCall(const Proto::Staking& staking) const {
             for (auto i = 0; i < staking.bond_and_nominate().nominators_size(); ++i) {
                 nominate->add_nominators(staking.bond_and_nominate().nominators(i));
             }
+            auto callIndices = staking.bond_and_nominate().nominate_call_indices();
+            nominate->mutable_call_indices()->CopyFrom(callIndices);
             // recursive call
             call2 = encodeStakingCall(staking2);
         }
@@ -283,7 +287,9 @@ Data Extrinsic::encodeStakingCall(const Proto::Staking& staking) const {
         Data call1;
         {
             auto staking1 = Proto::Staking();
-            staking1.mutable_chill();
+            auto* chill = staking1.mutable_chill();
+            auto callIndices = staking.chill_and_unbond().chill_call_indices();
+            chill->mutable_call_indices()->CopyFrom(callIndices);
             // recursive call
             call1 = encodeStakingCall(staking1);
         }
@@ -294,6 +300,8 @@ Data Extrinsic::encodeStakingCall(const Proto::Staking& staking) const {
             auto staking2 = Proto::Staking();
             auto* unbond = staking2.mutable_unbond();
             unbond->set_value(staking.chill_and_unbond().value());
+            auto callIndices = staking.chill_and_unbond().unbond_call_indices();
+            unbond->mutable_call_indices()->CopyFrom(callIndices);
             // recursive call
             call2 = encodeStakingCall(staking2);
         }
diff --git a/src/proto/Polkadot.proto b/src/proto/Polkadot.proto
index c25ddbd019e..719ccdddef5 100644
--- a/src/proto/Polkadot.proto
+++ b/src/proto/Polkadot.proto
@@ -131,6 +131,12 @@ message Staking {
 
         // call indices
         CallIndices call_indices = 5;
+
+        // Staking.Bond call indices
+        CallIndices bond_call_indices = 6;
+
+        // Staking.Nominate call indices
+        CallIndices nominate_call_indices = 7;
     }
 
     // Bond extra amount
@@ -184,6 +190,12 @@ message Staking {
 
         // call indices
         CallIndices call_indices = 2;
+
+        // Staking.Chill call indices
+        CallIndices chill_call_indices = 3;
+
+        // Staking.Unbond call indices
+        CallIndices unbond_call_indices = 4;
     }
 
     // Chill
diff --git a/tests/chains/Polkadot/SignerTests.cpp b/tests/chains/Polkadot/SignerTests.cpp
index 7e712160f51..2e4ae5b7f71 100644
--- a/tests/chains/Polkadot/SignerTests.cpp
+++ b/tests/chains/Polkadot/SignerTests.cpp
@@ -373,6 +373,112 @@ TEST(PolkadotSigner, PolymeshEncodeAndSign) {
     ASSERT_EQ(hex(encoded), "bd0284004322cf71da08f9d56181a707af7c0c437dfcb93e6caac9825a5aba57548142ee000791ee378775eaff34ef7e529ab742f0d81d281fdf20ace0aa765ca484f5909c4eea0a59c8dbbc534c832704924b424ba3230c38acd0ad5360cef023ca2a420f25010400050100849e2f6b165d4b28b39ef3d98f86c0520d82bc349536324365c10af08f323f8302093d00014d454d4f20504144444544205749544820535041434553000000000000000000");
 }
 
+TEST(PolkadotSigner, PolymeshEncodeBondAndNominate) {
+    // tx on mainnet
+    // https://polymesh.subscan.io/extrinsic/0xd516d4cb1f5ade29e557586e370e98c141c90d87a0b7547d98c6580eb2afaeeb
+
+    Polkadot::Proto::SigningInput input;
+    input.set_network(12);
+    input.set_multi_address(true);
+    auto blockHash = parse_hex("ab67744c78f1facfec9e517810a47ae23bc438315a01dac5ffee46beed5ad3d8");
+    auto vGenesisHash = parse_hex("6fbd74e5e1d0a61d52ccfe9d4adaed16dd3a7caa37c6bc4d0c2fa12e8b2f4063");
+    input.set_block_hash(std::string(blockHash.begin(), blockHash.end()));
+    input.set_genesis_hash(std::string(vGenesisHash.begin(), vGenesisHash.end()));
+    input.set_nonce(0UL);
+    input.set_spec_version(6003050u);
+    input.set_transaction_version(4u);
+
+    auto* era = input.mutable_era();
+    era->set_block_number(15742961UL);
+    era->set_period(64UL);
+
+    auto stakingCall = input.mutable_staking_call();
+    auto bondnom = stakingCall->mutable_bond_and_nominate();
+    auto value = store(uint256_t(4000000)); // 4.0 POLYX
+    bondnom->set_controller("2EYbDVDVWiFbXZWJgqGDJsiH5MfNeLr5fxqH3tX84LQZaETG");
+    bondnom->set_value(value.data(), value.size());
+    bondnom->set_reward_destination(Proto::RewardDestination::STAKED);
+    bondnom->add_nominators("2Gw8mSc4CUMxXMKEDqEsumQEXE5yTF8ACq2KdHGuigyXkwtz");
+
+    // Utiltity.batch_all
+    {
+      auto* callIndices = bondnom->mutable_call_indices()->mutable_custom();
+      callIndices->set_module_index(0x29);
+      callIndices->set_method_index(0x02);
+    }
+
+    // Staking.bond
+    {
+      auto* callIndices = bondnom->mutable_bond_call_indices()->mutable_custom();
+      callIndices->set_module_index(0x11);
+      callIndices->set_method_index(0x00);
+    }
+
+    // Staking.nominate
+    {
+      auto* callIndices = bondnom->mutable_nominate_call_indices()->mutable_custom();
+      callIndices->set_module_index(0x11);
+      callIndices->set_method_index(0x05);
+    }
+
+    auto preImage = Signer::signaturePreImage(input);
+    ASSERT_EQ(hex(preImage), "2902081100005ccc5c9276ab7976e7c93c70c190fbf1761578c07b892d0d1fe65972f6a290610224f4000011050400c6766ff780e1f506e41622f7798ec9323ab3b8bea43767d8c107e1e920581958150300006a995b00040000006fbd74e5e1d0a61d52ccfe9d4adaed16dd3a7caa37c6bc4d0c2fa12e8b2f4063ab67744c78f1facfec9e517810a47ae23bc438315a01dac5ffee46beed5ad3d8");
+
+    auto publicKey = parse_hex("5ccc5c9276ab7976e7c93c70c190fbf1761578c07b892d0d1fe65972f6a29061");
+    auto signature = parse_hex("685a2fd4b1bdf7775c55eb97302a0f86b0c10848fd9db3a7f6bbe912c4c2fa28bed16f6032852ec14f27f0553523dd2fc181a6dca79f19f9c7ed6cb660cf6480");
+    auto encoded = Signer::encodeTransaction(input, publicKey, signature);
+    ASSERT_EQ(hex(encoded), "d90284005ccc5c9276ab7976e7c93c70c190fbf1761578c07b892d0d1fe65972f6a2906100685a2fd4b1bdf7775c55eb97302a0f86b0c10848fd9db3a7f6bbe912c4c2fa28bed16f6032852ec14f27f0553523dd2fc181a6dca79f19f9c7ed6cb660cf6480150300002902081100005ccc5c9276ab7976e7c93c70c190fbf1761578c07b892d0d1fe65972f6a290610224f4000011050400c6766ff780e1f506e41622f7798ec9323ab3b8bea43767d8c107e1e920581958");
+}
+
+TEST(PolkadotSigner, PolymeshEncodeChillAndUnbond) {
+    // extrinsic on mainnet
+    // https://mainnet-app.polymesh.network/#/extrinsics/decode/0x29020811061102027a030a
+
+    Polkadot::Proto::SigningInput input;
+    input.set_network(12);
+    input.set_multi_address(true);
+    auto blockHash = parse_hex("ab67744c78f1facfec9e517810a47ae23bc438315a01dac5ffee46beed5ad3d8");
+    auto vGenesisHash = parse_hex("6fbd74e5e1d0a61d52ccfe9d4adaed16dd3a7caa37c6bc4d0c2fa12e8b2f4063");
+    input.set_block_hash(std::string(blockHash.begin(), blockHash.end()));
+    input.set_genesis_hash(std::string(vGenesisHash.begin(), vGenesisHash.end()));
+    input.set_nonce(0UL);
+    input.set_spec_version(6003050u);
+    input.set_transaction_version(4u);
+
+    auto* era = input.mutable_era();
+    era->set_block_number(15742961UL);
+    era->set_period(64UL);
+
+    auto stakingCall = input.mutable_staking_call();
+    auto chillBond = stakingCall->mutable_chill_and_unbond();
+    auto value = store(uint256_t(42000000)); // 42.0 POLYX
+    chillBond->set_value(value.data(), value.size());
+
+    // Utiltity.batch_all
+    {
+      auto* callIndices = chillBond->mutable_call_indices()->mutable_custom();
+      callIndices->set_module_index(0x29);
+      callIndices->set_method_index(0x02);
+    }
+
+    // Staking.bond
+    {
+      auto* callIndices = chillBond->mutable_chill_call_indices()->mutable_custom();
+      callIndices->set_module_index(0x11);
+      callIndices->set_method_index(0x06);
+    }
+
+    // Staking.nominate
+    {
+      auto* callIndices = chillBond->mutable_unbond_call_indices()->mutable_custom();
+      callIndices->set_module_index(0x11);
+      callIndices->set_method_index(0x02);
+    }
+
+    auto preImage = Signer::signaturePreImage(input);
+    ASSERT_EQ(hex(preImage), "29020811061102027a030a150300006a995b00040000006fbd74e5e1d0a61d52ccfe9d4adaed16dd3a7caa37c6bc4d0c2fa12e8b2f4063ab67744c78f1facfec9e517810a47ae23bc438315a01dac5ffee46beed5ad3d8");
+}
+
 TEST(PolkadotSigner, Statemint_encodeTransaction_transfer) {
     // tx on mainnet
     // https://statemint.subscan.io/extrinsic/2686030-2

From 99b69d1c2267354270769f6adef2d370553ce436 Mon Sep 17 00:00:00 2001
From: praveen-kaia <112046567+praveen-kaia@users.noreply.github.com>
Date: Sat, 7 Dec 2024 01:25:04 +0800
Subject: [PATCH 4/7] Updated KAIA symbol from KLAY (#4153)

Co-authored-by: Sergei Boiko <127754187+satoshiotomakan@users.noreply.github.com>
---
 docs/registry.md                        | 2 +-
 registry.json                           | 2 +-
 tests/chains/Klaytn/TWCoinTypeTests.cpp | 2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/docs/registry.md b/docs/registry.md
index a5045889d19..8a109c526d2 100644
--- a/docs/registry.md
+++ b/docs/registry.md
@@ -131,7 +131,7 @@ This list is generated from [./registry.json](../registry.json)
 | 10004689 | IoTeX EVM        | IOTX   | <img src="https://raw.githubusercontent.com/trustwallet/assets/master/blockchains/iotexevm/info/logo.png" width="32" />     | <https://iotex.io/>           |
 | 10007000 | NativeZetaChain  | ZETA   | <img src="https://raw.githubusercontent.com/trustwallet/assets/master/blockchains/zetachain/info/logo.png" width="32" />    | <https://www.zetachain.com/>  |
 | 10007700 | NativeCanto      | CANTO  | <img src="https://raw.githubusercontent.com/trustwallet/assets/master/blockchains/nativecanto/info/logo.png" width="32" />  | <https://canto.io/>           |
-| 10008217 | Kaia             | KLAY   | <img src="https://raw.githubusercontent.com/trustwallet/assets/master/blockchains/kaia/info/logo.png" width="32" />         | <https://kaia.io>             |
+| 10008217 | Kaia             | KAIA   | <img src="https://raw.githubusercontent.com/trustwallet/assets/master/blockchains/kaia/info/logo.png" width="32" />         | <https://kaia.io>             |
 | 10009000 | Avalanche C-Chain | AVAX   | <img src="https://raw.githubusercontent.com/trustwallet/assets/master/blockchains/avalanchec/info/logo.png" width="32" />   | <https://www.avalabs.org/>    |
 | 10009001 | Evmos            | EVMOS  | <img src="https://raw.githubusercontent.com/trustwallet/assets/master/blockchains/evmos/info/logo.png" width="32" />        | <https://evmos.org/>          |
 | 10042170 | Arbitrum Nova    | ETH    | <img src="https://raw.githubusercontent.com/trustwallet/assets/master/blockchains/arbitrumnova/info/logo.png" width="32" /> | <https://nova.arbitrum.io>    |
diff --git a/registry.json b/registry.json
index d88798aff9c..71b186efe08 100644
--- a/registry.json
+++ b/registry.json
@@ -4066,7 +4066,7 @@
     "id": "kaia",
     "name": "Kaia",
     "coinId": 10008217,
-    "symbol": "KLAY",
+    "symbol": "KAIA",
     "decimals": 18,
     "blockchain": "Ethereum",
     "derivation": [
diff --git a/tests/chains/Klaytn/TWCoinTypeTests.cpp b/tests/chains/Klaytn/TWCoinTypeTests.cpp
index 3a07d5df016..b0f180f85a7 100644
--- a/tests/chains/Klaytn/TWCoinTypeTests.cpp
+++ b/tests/chains/Klaytn/TWCoinTypeTests.cpp
@@ -24,7 +24,7 @@ TEST(TWKaiaCoinType, TWCoinType) {
 
     assertStringsEqual(id, "kaia");
     assertStringsEqual(name, "Kaia");
-    assertStringsEqual(symbol, "KLAY");
+    assertStringsEqual(symbol, "KAIA");
     ASSERT_EQ(TWCoinTypeConfigurationGetDecimals(coin), 18);
     ASSERT_EQ(TWCoinTypeBlockchain(coin), TWBlockchainEthereum);
     ASSERT_EQ(TWCoinTypeP2shPrefix(coin), 0x0);

From a3372c97c8fbcc0b7b6a98b6f140c465acf97739 Mon Sep 17 00:00:00 2001
From: Sergei Boiko <127754187+satoshiotomakan@users.noreply.github.com>
Date: Wed, 11 Dec 2024 18:24:39 +0700
Subject: [PATCH 5/7] [Security]: Rename `ExpandedSecretKey::sign_with_pubkey`
 to `dangerous_sign_with_pubkey` (#4154)

* [Security]: Make `ExpandedSecretKey::sign_with_pubkey` unsafe

* [Security]: Rename `ExpandedSecretKey::sign_with_pubkey` to `dangerous_sign_with_pubkey`
---
 rust/tw_keypair/src/ed25519/keypair.rs            |  2 +-
 .../modifications/cardano/extended_keypair.rs     |  3 +--
 .../modifications/cardano/extended_private.rs     | 15 +++------------
 rust/tw_keypair/src/ed25519/private.rs            | 13 ++-----------
 rust/tw_keypair/src/ed25519/secret.rs             | 12 ++++++++++--
 5 files changed, 17 insertions(+), 28 deletions(-)

diff --git a/rust/tw_keypair/src/ed25519/keypair.rs b/rust/tw_keypair/src/ed25519/keypair.rs
index 3ac2ac1e1fa..636bbb0ad68 100644
--- a/rust/tw_keypair/src/ed25519/keypair.rs
+++ b/rust/tw_keypair/src/ed25519/keypair.rs
@@ -33,7 +33,7 @@ impl<H: Hasher512> SigningKeyTrait for KeyPair<H> {
     type Signature = Signature;
 
     fn sign(&self, message: Self::SigningMessage) -> KeyPairResult<Self::Signature> {
-        self.private().sign_with_public_key(self.public(), &message)
+        self.private().sign(message)
     }
 }
 
diff --git a/rust/tw_keypair/src/ed25519/modifications/cardano/extended_keypair.rs b/rust/tw_keypair/src/ed25519/modifications/cardano/extended_keypair.rs
index f746f12d6d1..eef6895bde7 100644
--- a/rust/tw_keypair/src/ed25519/modifications/cardano/extended_keypair.rs
+++ b/rust/tw_keypair/src/ed25519/modifications/cardano/extended_keypair.rs
@@ -35,8 +35,7 @@ impl<H: Hasher512> SigningKeyTrait for ExtendedKeyPair<H> {
     type Signature = Signature;
 
     fn sign(&self, message: Self::SigningMessage) -> KeyPairResult<Self::Signature> {
-        self.private()
-            .sign_with_public_key(self.public(), message.as_slice())
+        self.private().sign(message)
     }
 }
 
diff --git a/rust/tw_keypair/src/ed25519/modifications/cardano/extended_private.rs b/rust/tw_keypair/src/ed25519/modifications/cardano/extended_private.rs
index f2fac1a0687..6a2bd83124a 100644
--- a/rust/tw_keypair/src/ed25519/modifications/cardano/extended_private.rs
+++ b/rust/tw_keypair/src/ed25519/modifications/cardano/extended_private.rs
@@ -43,17 +43,6 @@ impl<H: Hasher512> ExtendedPrivateKey<H> {
 
         ExtendedPublicKey::new(key, second_key)
     }
-
-    /// `ed25519` signing uses a public key associated with the private key.
-    pub(crate) fn sign_with_public_key(
-        &self,
-        public: &ExtendedPublicKey<H>,
-        message: &[u8],
-    ) -> KeyPairResult<Signature> {
-        self.key
-            .expanded_key
-            .sign_with_pubkey(public.key_for_signing(), message)
-    }
 }
 
 impl<H: Hasher512> SigningKeyTrait for ExtendedPrivateKey<H> {
@@ -61,7 +50,9 @@ impl<H: Hasher512> SigningKeyTrait for ExtendedPrivateKey<H> {
     type Signature = Signature;
 
     fn sign(&self, message: Self::SigningMessage) -> KeyPairResult<Self::Signature> {
-        self.sign_with_public_key(&self.public(), message.as_slice())
+        self.key
+            .expanded_key
+            .dangerous_sign_with_pubkey(self.public().key_for_signing(), message.as_slice())
     }
 }
 
diff --git a/rust/tw_keypair/src/ed25519/private.rs b/rust/tw_keypair/src/ed25519/private.rs
index 984392393a6..ce0c2ef056f 100644
--- a/rust/tw_keypair/src/ed25519/private.rs
+++ b/rust/tw_keypair/src/ed25519/private.rs
@@ -36,16 +36,6 @@ impl<H: Hasher512> PrivateKey<H> {
     pub fn public(&self) -> PublicKey<H> {
         PublicKey::with_expanded_secret(&self.expanded_key)
     }
-
-    /// `ed25519` signing uses a public key associated with the private key.
-    pub(crate) fn sign_with_public_key(
-        &self,
-        public: &PublicKey<H>,
-        message: &[u8],
-    ) -> KeyPairResult<Signature> {
-        self.expanded_key
-            .sign_with_pubkey(public.to_bytes(), message)
-    }
 }
 
 impl<H: Hasher512> SigningKeyTrait for PrivateKey<H> {
@@ -53,7 +43,8 @@ impl<H: Hasher512> SigningKeyTrait for PrivateKey<H> {
     type Signature = Signature;
 
     fn sign(&self, message: Self::SigningMessage) -> KeyPairResult<Self::Signature> {
-        self.sign_with_public_key(&self.public(), &message)
+        self.expanded_key
+            .dangerous_sign_with_pubkey(self.public().to_bytes(), &message)
     }
 }
 
diff --git a/rust/tw_keypair/src/ed25519/secret.rs b/rust/tw_keypair/src/ed25519/secret.rs
index 895f788b15d..5265b3a06d9 100644
--- a/rust/tw_keypair/src/ed25519/secret.rs
+++ b/rust/tw_keypair/src/ed25519/secret.rs
@@ -69,8 +69,14 @@ impl<H: Hasher512> ExpandedSecretKey<H> {
     /// Signs a message with this `ExpandedSecretKey`.
     /// Source: https://github.com/dalek-cryptography/ed25519-dalek/blob/1.0.1/src/secret.rs#L389-L412
     /// Ported: https://github.com/trustwallet/wallet-core/blob/423f0e34725f69c0a9d535e1a32534c99682edea/trezor-crypto/crypto/ed25519-donna/ed25519.c#L97-L130
+    ///
+    /// # Important
+    ///
+    /// Ensure that the public key is always correctly paired with the private key,
+    /// preventing scenarios where an arbitrary public key could be introduced into the signing process.
+    /// Security report: https://github.com/trustwallet/wallet-core/security/advisories/GHSA-7g72-jxww-q9vq
     #[allow(non_snake_case)]
-    pub(crate) fn sign_with_pubkey(
+    pub(crate) fn dangerous_sign_with_pubkey(
         &self,
         pubkey: H256,
         message: &[u8],
@@ -122,7 +128,9 @@ mod tests {
         let message = hex::decode("f0").unwrap();
 
         // Anyway, the result signature has an expected value.
-        let sign = secret_key.sign_with_pubkey(public, &message).unwrap();
+        let sign = secret_key
+            .dangerous_sign_with_pubkey(public, &message)
+            .unwrap();
         let expected = H512::from("ed55bce14a845a275e7a3a7242420ed1eeaba79dc3141bebf42ca0d12169e209a6e56b6981a336f711ae3aaea8d063b72b0e79a8808311d08cb42cabfdd0450d");
         assert_eq!(sign.to_bytes(), expected);
     }

From dd612bbf2a85c1eaf5e7e506da6b462bc6249542 Mon Sep 17 00:00:00 2001
From: denis15yo <57437689+denis15yo@users.noreply.github.com>
Date: Wed, 11 Dec 2024 18:37:17 +0300
Subject: [PATCH 6/7] Update Package.swift version to 4.1.21 (#4163)

Co-authored-by: Denis Shilovich <denis.shilovich@mobyrix.com>
---
 Package.swift | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/Package.swift b/Package.swift
index 7e933efe93d..68de23747c4 100644
--- a/Package.swift
+++ b/Package.swift
@@ -12,13 +12,13 @@ let package = Package(
     targets: [
         .binaryTarget(
             name: "WalletCore",
-            url: "https://github.com/trustwallet/wallet-core/releases/download/4.1.12/WalletCore.xcframework.zip",
-            checksum: "1632bbbab1c6a588689eec77a24e1468d9a6746968652cf0a7e669e996c3d24d"
+            url: "https://github.com/trustwallet/wallet-core/releases/download/4.1.21/WalletCore.xcframework.zip",
+            checksum: "503937e1013bb7c1f610a8a4ec74a6ccdedb06bdec9fa9126ac47e25a90da06a"
         ),
         .binaryTarget(
             name: "SwiftProtobuf",
-            url: "https://github.com/trustwallet/wallet-core/releases/download/4.1.12/SwiftProtobuf.xcframework.zip",
-            checksum: "33d80c20428c9db4fcf99d1272ba19655f7c6ee7e5b1809fa8a7e7d4aa1b222b"
+            url: "https://github.com/trustwallet/wallet-core/releases/download/4.1.21/SwiftProtobuf.xcframework.zip",
+            checksum: "f6da2b8fafdce5e8d46ea305972f1ad942cc796f63026a32c883331dd3813285"
         )
     ]
 )

From b37b7809c619a97a826747a73295a07e8f4c9417 Mon Sep 17 00:00:00 2001
From: 10gic <github10gic@proton.me>
Date: Mon, 16 Dec 2024 16:52:31 +0800
Subject: [PATCH 7/7] [Solana]: Support specifying fee payer for an encoded
 transaction (#4156)

* Support specifying fee payer for an encoded transaction

* Add some comments

* Exports solana setFeePayer function to kotlin/swift code

* Fix swift test case

* Fix swift test case
---
 .../solana/TestSolanaTransaction.kt           | 15 ++++
 include/TrustWalletCore/TWSolanaTransaction.h | 12 ++-
 .../src/modules/insert_instruction.rs         | 31 +++++++
 rust/chains/tw_solana/src/modules/utils.rs    | 15 ++++
 .../chains/solana/solana_transaction_ffi.rs   | 87 ++++++++++++++++++-
 .../src/ffi/solana/transaction.rs             | 23 +++++
 src/interface/TWSolanaTransaction.cpp         | 17 ++++
 swift/Tests/Blockchains/SolanaTests.swift     | 48 ++++++++++
 tests/chains/Solana/TWSolanaTransaction.cpp   | 54 ++++++++++++
 9 files changed, 297 insertions(+), 5 deletions(-)

diff --git a/android/app/src/androidTest/java/com/trustwallet/core/app/blockchains/solana/TestSolanaTransaction.kt b/android/app/src/androidTest/java/com/trustwallet/core/app/blockchains/solana/TestSolanaTransaction.kt
index a7f1ca53348..535970c9957 100644
--- a/android/app/src/androidTest/java/com/trustwallet/core/app/blockchains/solana/TestSolanaTransaction.kt
+++ b/android/app/src/androidTest/java/com/trustwallet/core/app/blockchains/solana/TestSolanaTransaction.kt
@@ -118,4 +118,19 @@ class TestSolanaTransaction {
         val expectedString = "AVUye82Mv+/aWeU2G+B6Nes365mUU2m8iqcGZn/8kFJvw4wY6AgKGG+vJHaknHlCDwE1yi1SIMVUUtNCOm3kHg8BAAIEODI+iWe7g68B9iwCy8bFkJKvsIEj350oSOpcv4gNnv/st+6qmqipl9lwMK6toB9TiL7LrJVfij+pKwr+pUKxfwAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAwZGb+UhFzL/7K26csOb57yM5bvF9xJrLEObOkAAAAAboZ09wD3Y5HNUl7aN8bwpCqowev1hMu7fSgziLswUSgMDAAUCECcAAAICAAEMAgAAAOgDAAAAAAAAAwAJA+gDAAAAAAAA"
         assertEquals(output.encoded, expectedString)
     }
+
+    @Test
+    fun testSetFeePayer() {
+        val originalTx = "AQAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAACAAQABA2uEKrOPvZNBtdUtSFXcg8+kj4O/Z1Ht/hwvnaqq5s6mTXd3KtwUyJFfRs2PBfeQW8xCEZvNr/5J/Tx8ltbn0pwAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAACo+QRbvXWNKoOfaOL4cSpfYrmn/2TV+dBmct+HsmmwdAQICAAEMAgAAAACcnwYAAAAAAA=="
+
+        // Step 1 - Add fee payer to the transaction.
+        val updatedTx = SolanaTransaction.setFeePayer(originalTx, "Eg5jqooyG6ySaXKbQUu4Lpvu2SqUPZrNkM4zXs9iUDLJ")
+        assertEquals(updatedTx, "AgAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAgAIAAQTLKvCJtWpVdze8Fxjgy/Iyz1sC4U7gqnxmdSM/X2+bV2uEKrOPvZNBtdUtSFXcg8+kj4O/Z1Ht/hwvnaqq5s6mTXd3KtwUyJFfRs2PBfeQW8xCEZvNr/5J/Tx8ltbn0pwAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAACo+QRbvXWNKoOfaOL4cSpfYrmn/2TV+dBmct+HsmmwdAQMCAQIMAgAAAACcnwYAAAAAAA==")
+
+        // This case originates from a test case in C++. Here, only the most critical function is verified for correctness,
+        // while the remaining steps have been omitted.
+        // Step 2 - Decode transaction into a `RawMessage` Protobuf.
+        // Step 3 - Obtain preimage hash.
+        // Step 4 - Compile transaction info.
+    }
 }
\ No newline at end of file
diff --git a/include/TrustWalletCore/TWSolanaTransaction.h b/include/TrustWalletCore/TWSolanaTransaction.h
index 871393fc840..420a84ca7b6 100644
--- a/include/TrustWalletCore/TWSolanaTransaction.h
+++ b/include/TrustWalletCore/TWSolanaTransaction.h
@@ -50,7 +50,7 @@ TWString *_Nullable TWSolanaTransactionGetComputeUnitLimit(TWString *_Nonnull en
 /// and returns the updated transaction.
 ///
 /// \param encodedTx base64 encoded Solana transaction.
-/// \price Unit Price as a decimal string.
+/// \param price Unit Price as a decimal string.
 /// \return base64 encoded Solana transaction. Null if an error occurred.
 TW_EXPORT_STATIC_METHOD
 TWString *_Nullable TWSolanaTransactionSetComputeUnitPrice(TWString *_Nonnull encodedTx, TWString *_Nonnull price);
@@ -59,9 +59,17 @@ TWString *_Nullable TWSolanaTransactionSetComputeUnitPrice(TWString *_Nonnull en
 /// and returns the updated transaction.
 ///
 /// \param encodedTx base64 encoded Solana transaction.
-/// \limit Unit Limit as a decimal string.
+/// \param limit Unit Limit as a decimal string.
 /// \return base64 encoded Solana transaction. Null if an error occurred.
 TW_EXPORT_STATIC_METHOD
 TWString *_Nullable TWSolanaTransactionSetComputeUnitLimit(TWString *_Nonnull encodedTx, TWString *_Nonnull limit);
 
+/// Adds fee payer to the given transaction and returns the updated transaction.
+///
+/// \param encodedTx base64 encoded Solana transaction.
+/// \param feePayer fee payer account address. Must be a base58 encoded public key. It must NOT be in the account list yet.
+/// \return base64 encoded Solana transaction. Null if an error occurred.
+TW_EXPORT_STATIC_METHOD
+TWString *_Nullable TWSolanaTransactionSetFeePayer(TWString *_Nonnull encodedTx, TWString *_Nonnull feePayer);
+
 TW_EXTERN_C_END
diff --git a/rust/chains/tw_solana/src/modules/insert_instruction.rs b/rust/chains/tw_solana/src/modules/insert_instruction.rs
index 22643e349ce..36c1c583de3 100644
--- a/rust/chains/tw_solana/src/modules/insert_instruction.rs
+++ b/rust/chains/tw_solana/src/modules/insert_instruction.rs
@@ -91,6 +91,37 @@ pub trait InsertInstruction {
         Ok(account_added_at)
     }
 
+    /// Adds a fee payer account to the message.
+    /// Note: The fee payer must NOT be in the account list yet.
+    fn set_fee_payer(&mut self, account: SolanaAddress) -> SigningResult<()> {
+        if self.account_keys_mut().contains(&account) {
+            // For security reasons, we don't allow adding a fee payer if it's already in the account list.
+            //
+            // If the fee payer is already in the transaction and there is a malicious instruction to
+            // transfer tokens from the fee payer to another account, The fee payer may have inadvertently
+            // signed off on such transactions, which is not what they would expect.
+            //
+            // Such examples may be difficult to exploit, but we still took precautionary measures to prohibit
+            // the new fee payer from appearing in the account list of the transaction out of caution
+            return SigningError::err(SigningErrorType::Error_internal)
+                .context("Fee payer account is already in the account list");
+        }
+
+        // Insert the fee payer account at the beginning of the account list.
+        self.account_keys_mut().insert(0, account);
+        self.message_header_mut().num_required_signatures += 1;
+
+        // Update `program id indexes` and `account id indexes` in every instruction as we inserted the account at the beginning of the list.
+        self.instructions_mut().iter_mut().for_each(|ix| {
+            ix.program_id_index += 1; // Update `program id indexes`
+            ix.accounts
+                .iter_mut()
+                .for_each(|account_id| *account_id += 1); // Update `account id indexes`
+        });
+
+        Ok(())
+    }
+
     /// Returns ALT (Address Lookup Tables) if supported by the message version.
     fn address_table_lookups(&self) -> Option<&[MessageAddressTableLookup]>;
 
diff --git a/rust/chains/tw_solana/src/modules/utils.rs b/rust/chains/tw_solana/src/modules/utils.rs
index da19b9d17d8..0d7f61dd8a3 100644
--- a/rust/chains/tw_solana/src/modules/utils.rs
+++ b/rust/chains/tw_solana/src/modules/utils.rs
@@ -2,6 +2,7 @@
 //
 // Copyright © 2017 Trust Wallet.
 
+use crate::address::SolanaAddress;
 use crate::defined_addresses::{COMPUTE_BUDGET_ADDRESS, SYSTEM_PROGRAM_ID_ADDRESS};
 use crate::modules::insert_instruction::InsertInstruction;
 use crate::modules::instruction_builder::compute_budget_instruction::{
@@ -158,6 +159,20 @@ impl SolanaTransaction {
 
         tx.to_base64().tw_err(|_| SigningErrorType::Error_internal)
     }
+
+    pub fn set_fee_payer(encoded_tx: &str, fee_payer: SolanaAddress) -> SigningResult<String> {
+        let tx_bytes = base64::decode(encoded_tx, STANDARD)?;
+        let mut tx: VersionedTransaction =
+            bincode::deserialize(&tx_bytes).map_err(|_| SigningErrorType::Error_input_parse)?;
+
+        tx.message.set_fee_payer(fee_payer)?;
+
+        // Set the correct number of zero signatures
+        let unsigned_tx = VersionedTransaction::unsigned(tx.message);
+        unsigned_tx
+            .to_base64()
+            .tw_err(|_| SigningErrorType::Error_internal)
+    }
 }
 
 fn try_instruction_as_compute_budget(
diff --git a/rust/tw_tests/tests/chains/solana/solana_transaction_ffi.rs b/rust/tw_tests/tests/chains/solana/solana_transaction_ffi.rs
index a9a31f80da0..f0bd2c55622 100644
--- a/rust/tw_tests/tests/chains/solana/solana_transaction_ffi.rs
+++ b/rust/tw_tests/tests/chains/solana/solana_transaction_ffi.rs
@@ -2,11 +2,11 @@
 //
 // Copyright © 2017 Trust Wallet.
 
-use tw_any_coin::test_utils::sign_utils::AnySignerHelper;
+use tw_any_coin::test_utils::sign_utils::{AnySignerHelper, CompilerHelper, PreImageHelper};
 use tw_any_coin::test_utils::transaction_decode_utils::TransactionDecoderHelper;
 use tw_coin_registry::coin_type::CoinType;
 use tw_encoding::base64::STANDARD;
-use tw_encoding::hex::DecodeHex;
+use tw_encoding::hex::{DecodeHex, ToHex};
 use tw_encoding::{base58, base64};
 use tw_memory::test_utils::tw_data_helper::TWDataHelper;
 use tw_memory::test_utils::tw_data_vector_helper::TWDataVectorHelper;
@@ -17,7 +17,7 @@ use tw_solana::SOLANA_ALPHABET;
 use wallet_core_rs::ffi::solana::transaction::{
     tw_solana_transaction_get_compute_unit_limit, tw_solana_transaction_get_compute_unit_price,
     tw_solana_transaction_set_compute_unit_limit, tw_solana_transaction_set_compute_unit_price,
-    tw_solana_transaction_update_blockhash_and_sign,
+    tw_solana_transaction_set_fee_payer, tw_solana_transaction_update_blockhash_and_sign,
 };
 
 #[test]
@@ -283,3 +283,84 @@ fn test_solana_transaction_set_priority_fee_transfer_with_address_lookup() {
         signature: "4vkDYvXnAyauDwgQUT9pjhvArCm1jZZFp6xFiT6SYKDHwabPNyNskzzd8YJZR4UJVXakBtRAFku3axVQoA7Apido",
     });
 }
+
+#[test]
+fn test_solana_transaction_set_fee_payer() {
+    let encoded_tx_str = "AQAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAACAAQABA2uEKrOPvZNBtdUtSFXcg8+kj4O/Z1Ht/hwvnaqq5s6mTXd3KtwUyJFfRs2PBfeQW8xCEZvNr/5J/Tx8ltbn0pwAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAACo+QRbvXWNKoOfaOL4cSpfYrmn/2TV+dBmct+HsmmwdAQICAAEMAgAAAACcnwYAAAAAAA==";
+    let encoded_tx = TWStringHelper::create(encoded_tx_str);
+
+    let fee_payer_str = "Eg5jqooyG6ySaXKbQUu4Lpvu2SqUPZrNkM4zXs9iUDLJ";
+    let fee_payer = TWStringHelper::create(fee_payer_str);
+
+    // Step 1 - Add fee payer to the transaction.
+    let updated_tx = TWStringHelper::wrap(unsafe {
+        tw_solana_transaction_set_fee_payer(encoded_tx.ptr(), fee_payer.ptr())
+    });
+    let updated_tx = updated_tx.to_string().unwrap();
+    assert_eq!(updated_tx, "AgAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAgAIAAQTLKvCJtWpVdze8Fxjgy/Iyz1sC4U7gqnxmdSM/X2+bV2uEKrOPvZNBtdUtSFXcg8+kj4O/Z1Ht/hwvnaqq5s6mTXd3KtwUyJFfRs2PBfeQW8xCEZvNr/5J/Tx8ltbn0pwAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAACo+QRbvXWNKoOfaOL4cSpfYrmn/2TV+dBmct+HsmmwdAQMCAQIMAgAAAACcnwYAAAAAAA==");
+
+    // Step 2 - Decode transaction into a `RawMessage` Protobuf.
+    let tx_data = base64::decode(&updated_tx, STANDARD).unwrap();
+    let mut decoder = TransactionDecoderHelper::<Proto::DecodingTransactionOutput>::default();
+    let output = decoder.decode(CoinType::Solana, tx_data);
+
+    assert_eq!(output.error, SigningError::OK);
+    let decoded_tx = output.transaction.unwrap();
+
+    let signing_input = Proto::SigningInput {
+        raw_message: Some(decoded_tx),
+        tx_encoding: Proto::Encoding::Base64,
+        ..Proto::SigningInput::default()
+    };
+
+    // Step 3 - Obtain preimage hash.
+    let mut pre_imager = PreImageHelper::<Proto::PreSigningOutput>::default();
+    let preimage_output = pre_imager.pre_image_hashes(CoinType::Solana, &signing_input);
+
+    assert_eq!(preimage_output.error, SigningError::OK);
+    assert_eq!(
+        preimage_output.data.to_hex(),
+        "8002000104cb2af089b56a557737bc1718e0cbf232cf5b02e14ee0aa7c6675233f5f6f9b576b842ab38fbd9341b5d52d4855dc83cfa48f83bf6751edfe1c2f9daaaae6cea64d77772adc14c8915f46cd8f05f7905bcc42119bcdaffe49fd3c7c96d6e7d29c00000000000000000000000000000000000000000000000000000000000000002a3e4116ef5d634aa0e7da38be1c4a97d8ae69ffd9357e74199cb7e1ec9a6c1d01030201020c02000000009c9f060000000000"
+    );
+
+    // Step 4 - Compile transaction info.
+    // Simulate signature, normally obtained from signature server.
+    let fee_payer_signature = "feb9f15cc345fa156450676100033860edbe80a6f61dab8199e94fdc47678ecfdb95e3bc10ec0a7f863ab8ef5c38edae72db7e5d72855db225fd935fd59b700a".decode_hex().unwrap();
+    let fee_payer_public_key = base58::decode(fee_payer_str, SOLANA_ALPHABET).unwrap();
+
+    let sol_sender_signature = "936cd6d176e701d1f748031925b2f029f6f1ab4b99aec76e24ccf05649ec269569a08ec0bd80f5fee1cb8d13ecd420bf50c5f64ae74c7afa267458cabb4e5804".decode_hex().unwrap();
+    let sol_sender_public_key = "6b842ab38fbd9341b5d52d4855dc83cfa48f83bf6751edfe1c2f9daaaae6cea6"
+        .decode_hex()
+        .unwrap();
+
+    let mut compiler = CompilerHelper::<Proto::SigningOutput>::default();
+    let output = compiler.compile(
+        CoinType::Solana,
+        &signing_input,
+        vec![fee_payer_signature, sol_sender_signature],
+        vec![fee_payer_public_key, sol_sender_public_key],
+    );
+
+    assert_eq!(output.error, SigningError::OK);
+    // Successfully broadcasted tx:
+    // https://explorer.solana.com/tx/66PAVjxFVGP4ctrkXmyNRhp6BdFT7gDe1k356DZzCRaBDTmJZF1ewGsbujWRjDTrt5utnz8oHZw3mg8qBNyct41w?cluster=devnet
+    assert_eq!(output.encoded, "Av658VzDRfoVZFBnYQADOGDtvoCm9h2rgZnpT9xHZ47P25XjvBDsCn+GOrjvXDjtrnLbfl1yhV2yJf2TX9WbcAqTbNbRducB0fdIAxklsvAp9vGrS5mux24kzPBWSewmlWmgjsC9gPX+4cuNE+zUIL9QxfZK50x6+iZ0WMq7TlgEgAIAAQTLKvCJtWpVdze8Fxjgy/Iyz1sC4U7gqnxmdSM/X2+bV2uEKrOPvZNBtdUtSFXcg8+kj4O/Z1Ht/hwvnaqq5s6mTXd3KtwUyJFfRs2PBfeQW8xCEZvNr/5J/Tx8ltbn0pwAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAACo+QRbvXWNKoOfaOL4cSpfYrmn/2TV+dBmct+HsmmwdAQMCAQIMAgAAAACcnwYAAAAAAA==");
+    assert_eq!(output.unsigned_tx, "gAIAAQTLKvCJtWpVdze8Fxjgy/Iyz1sC4U7gqnxmdSM/X2+bV2uEKrOPvZNBtdUtSFXcg8+kj4O/Z1Ht/hwvnaqq5s6mTXd3KtwUyJFfRs2PBfeQW8xCEZvNr/5J/Tx8ltbn0pwAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAACo+QRbvXWNKoOfaOL4cSpfYrmn/2TV+dBmct+HsmmwdAQMCAQIMAgAAAACcnwYAAAAAAA==");
+}
+
+#[test]
+fn test_solana_transaction_set_fee_payer_already_exists() {
+    let encoded_tx_str = "AQAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAACAAQABA2uEKrOPvZNBtdUtSFXcg8+kj4O/Z1Ht/hwvnaqq5s6mTXd3KtwUyJFfRs2PBfeQW8xCEZvNr/5J/Tx8ltbn0pwAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAACo+QRbvXWNKoOfaOL4cSpfYrmn/2TV+dBmct+HsmmwdAQICAAEMAgAAAACcnwYAAAAAAA==";
+    let encoded_tx = TWStringHelper::create(encoded_tx_str);
+
+    let fee_payer_str = "8EhWjZGEt58UKzeiburZVx6QQF3rbayScpDjPNqCx62q";
+    let fee_payer = TWStringHelper::create(fee_payer_str);
+
+    let updated_tx = TWStringHelper::wrap(unsafe {
+        tw_solana_transaction_set_fee_payer(encoded_tx.ptr(), fee_payer.ptr())
+    });
+
+    // The fee payer is already in the transaction.
+    // We expect tw_solana_transaction_set_fee_payer to return null.
+    assert_eq!(updated_tx.to_string(), None);
+}
diff --git a/rust/wallet_core_rs/src/ffi/solana/transaction.rs b/rust/wallet_core_rs/src/ffi/solana/transaction.rs
index 6f97e5803e3..78e6b7ac0ba 100644
--- a/rust/wallet_core_rs/src/ffi/solana/transaction.rs
+++ b/rust/wallet_core_rs/src/ffi/solana/transaction.rs
@@ -133,3 +133,26 @@ pub unsafe extern "C" fn tw_solana_transaction_set_compute_unit_limit(
         _ => std::ptr::null_mut(),
     }
 }
+
+/// Adds fee payer to the given transaction, and returns the updated transaction.
+///
+/// \param encoded_tx base64 encoded Solana transaction.
+/// \param fee_payer fee payer account address. Must be a base58 encoded public key. It must NOT be in the account list yet.
+/// \return base64 encoded Solana transaction. Null if an error occurred.
+#[no_mangle]
+pub unsafe extern "C" fn tw_solana_transaction_set_fee_payer(
+    encoded_tx: *const TWString,
+    fee_payer: *const TWString,
+) -> *mut TWString {
+    let encoded_tx = try_or_else!(TWString::from_ptr_as_ref(encoded_tx), std::ptr::null_mut);
+    let encoded_tx = try_or_else!(encoded_tx.as_str(), std::ptr::null_mut);
+
+    let fee_payer = try_or_else!(TWString::from_ptr_as_ref(fee_payer), std::ptr::null_mut);
+    let fee_payer = try_or_else!(fee_payer.as_str(), std::ptr::null_mut);
+    let fee_payer = try_or_else!(fee_payer.parse(), std::ptr::null_mut);
+
+    match SolanaTransaction::set_fee_payer(encoded_tx, fee_payer) {
+        Ok(updated_tx) => TWString::from(updated_tx).into_ptr(),
+        _ => std::ptr::null_mut(),
+    }
+}
diff --git a/src/interface/TWSolanaTransaction.cpp b/src/interface/TWSolanaTransaction.cpp
index f555f6eb5d7..7b06afcf67b 100644
--- a/src/interface/TWSolanaTransaction.cpp
+++ b/src/interface/TWSolanaTransaction.cpp
@@ -87,3 +87,20 @@ TWString *_Nullable TWSolanaTransactionSetComputeUnitLimit(TWString *_Nonnull en
     auto updatedTx = updatedTxStr.toStringOrDefault();
     return TWStringCreateWithUTF8Bytes(updatedTx.c_str());
 }
+
+TWString *_Nullable TWSolanaTransactionSetFeePayer(TWString *_Nonnull encodedTx, TWString *_Nonnull feePayer) {
+    auto& encodedTxRef = *reinterpret_cast<const std::string*>(encodedTx);
+    auto& feePayerRef = *reinterpret_cast<const std::string*>(feePayer);
+
+    const Rust::TWStringWrapper encodedTxStr = encodedTxRef;
+    const Rust::TWStringWrapper feePayerStr = feePayerRef;
+
+    Rust::TWStringWrapper updatedTxStr = Rust::tw_solana_transaction_set_fee_payer(encodedTxStr.get(), feePayerStr.get());
+
+    if (!updatedTxStr) {
+        return nullptr;
+    }
+
+    const auto updatedTx = updatedTxStr.toStringOrDefault();
+    return TWStringCreateWithUTF8Bytes(updatedTx.c_str());
+}
diff --git a/swift/Tests/Blockchains/SolanaTests.swift b/swift/Tests/Blockchains/SolanaTests.swift
index bb8f996363c..e84ced805eb 100644
--- a/swift/Tests/Blockchains/SolanaTests.swift
+++ b/swift/Tests/Blockchains/SolanaTests.swift
@@ -329,6 +329,54 @@ class SolanaTests: XCTestCase {
         // https://explorer.solana.com/tx/2ho7wZUXbDNz12xGfsXg2kcNMqkBAQjv7YNXNcVcuCmbC4p9FZe9ELeM2gMjq9MKQPpmE3nBW5pbdgwVCfNLr1h8
         XCTAssertEqual(output.encoded, "AVUye82Mv+/aWeU2G+B6Nes365mUU2m8iqcGZn/8kFJvw4wY6AgKGG+vJHaknHlCDwE1yi1SIMVUUtNCOm3kHg8BAAIEODI+iWe7g68B9iwCy8bFkJKvsIEj350oSOpcv4gNnv/st+6qmqipl9lwMK6toB9TiL7LrJVfij+pKwr+pUKxfwAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAwZGb+UhFzL/7K26csOb57yM5bvF9xJrLEObOkAAAAAboZ09wD3Y5HNUl7aN8bwpCqowev1hMu7fSgziLswUSgMDAAUCECcAAAICAAEMAgAAAOgDAAAAAAAAAwAJA+gDAAAAAAAA")
     }
+
+    func testSetFeePayer() throws {
+        // base64 encoded
+        let originalTx = "AQAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAACAAQABA2uEKrOPvZNBtdUtSFXcg8+kj4O/Z1Ht/hwvnaqq5s6mTXd3KtwUyJFfRs2PBfeQW8xCEZvNr/5J/Tx8ltbn0pwAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAACo+QRbvXWNKoOfaOL4cSpfYrmn/2TV+dBmct+HsmmwdAQICAAEMAgAAAACcnwYAAAAAAA=="
+
+        // Step 1 - Add fee payer to the transaction.
+        let updatedTx = SolanaTransaction.setFeePayer(encodedTx: originalTx, feePayer: "Eg5jqooyG6ySaXKbQUu4Lpvu2SqUPZrNkM4zXs9iUDLJ")!
+
+        XCTAssertEqual(updatedTx, "AgAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAgAIAAQTLKvCJtWpVdze8Fxjgy/Iyz1sC4U7gqnxmdSM/X2+bV2uEKrOPvZNBtdUtSFXcg8+kj4O/Z1Ht/hwvnaqq5s6mTXd3KtwUyJFfRs2PBfeQW8xCEZvNr/5J/Tx8ltbn0pwAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAACo+QRbvXWNKoOfaOL4cSpfYrmn/2TV+dBmct+HsmmwdAQMCAQIMAgAAAACcnwYAAAAAAA==")
+
+        // Step 2 - Decode transaction into a `RawMessage` Protobuf.
+        let updatedTxData = Base64.decode(string: updatedTx)!
+        let decodeOutputData = TransactionDecoder.decode(coinType: .solana, encodedTx: updatedTxData)
+        let decodeOutput = try SolanaDecodingTransactionOutput(serializedData: decodeOutputData)
+
+        XCTAssertEqual(decodeOutput.error, .ok)
+
+        // Step 3 - Obtain preimage hash.
+        let signingInput = SolanaSigningInput.with {
+            $0.rawMessage = decodeOutput.transaction
+            $0.txEncoding = .base64
+        }
+        let txInputData = try signingInput.serializedData() // Serialize input
+        let preImageHashes = TransactionCompiler.preImageHashes(coinType: .solana, txInputData: txInputData)
+        let preSigningOutput: SolanaPreSigningOutput = try SolanaPreSigningOutput(serializedData: preImageHashes)
+        XCTAssertEqual(preSigningOutput.error, CommonSigningError.ok)
+        XCTAssertEqual(preSigningOutput.data.hexString, "8002000104cb2af089b56a557737bc1718e0cbf232cf5b02e14ee0aa7c6675233f5f6f9b576b842ab38fbd9341b5d52d4855dc83cfa48f83bf6751edfe1c2f9daaaae6cea64d77772adc14c8915f46cd8f05f7905bcc42119bcdaffe49fd3c7c96d6e7d29c00000000000000000000000000000000000000000000000000000000000000002a3e4116ef5d634aa0e7da38be1c4a97d8ae69ffd9357e74199cb7e1ec9a6c1d01030201020c02000000009c9f060000000000")
+
+        // Step 4 - Compile transaction info.
+        // Simulate signature, normally obtained from signature server.
+        let signatureVec = DataVector()
+        let pubkeyVec = DataVector()
+        let feePayerSignature = Data(hexString: "feb9f15cc345fa156450676100033860edbe80a6f61dab8199e94fdc47678ecfdb95e3bc10ec0a7f863ab8ef5c38edae72db7e5d72855db225fd935fd59b700a")!
+        let feePayerPublicKey = Data(hexString: "cb2af089b56a557737bc1718e0cbf232cf5b02e14ee0aa7c6675233f5f6f9b57")!
+        signatureVec.add(data: feePayerSignature)
+        pubkeyVec.add(data: feePayerPublicKey)
+        let solSenderSignature = Data(hexString: "936cd6d176e701d1f748031925b2f029f6f1ab4b99aec76e24ccf05649ec269569a08ec0bd80f5fee1cb8d13ecd420bf50c5f64ae74c7afa267458cabb4e5804")!
+        let solSenderPublicKey = Data(hexString: "6b842ab38fbd9341b5d52d4855dc83cfa48f83bf6751edfe1c2f9daaaae6cea6")!
+        signatureVec.add(data: solSenderSignature)
+        pubkeyVec.add(data: solSenderPublicKey)
+
+        let compileWithSignatures = TransactionCompiler.compileWithSignatures(coinType: .solana, txInputData: txInputData, signatures: signatureVec, publicKeys: pubkeyVec)
+        let expectedTx = "Av658VzDRfoVZFBnYQADOGDtvoCm9h2rgZnpT9xHZ47P25XjvBDsCn+GOrjvXDjtrnLbfl1yhV2yJf2TX9WbcAqTbNbRducB0fdIAxklsvAp9vGrS5mux24kzPBWSewmlWmgjsC9gPX+4cuNE+zUIL9QxfZK50x6+iZ0WMq7TlgEgAIAAQTLKvCJtWpVdze8Fxjgy/Iyz1sC4U7gqnxmdSM/X2+bV2uEKrOPvZNBtdUtSFXcg8+kj4O/Z1Ht/hwvnaqq5s6mTXd3KtwUyJFfRs2PBfeQW8xCEZvNr/5J/Tx8ltbn0pwAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAACo+QRbvXWNKoOfaOL4cSpfYrmn/2TV+dBmct+HsmmwdAQMCAQIMAgAAAACcnwYAAAAAAA=="
+        let output: SolanaSigningOutput = try SolanaSigningOutput(serializedData: compileWithSignatures)
+        XCTAssertEqual(output.encoded, expectedTx)
+        // Successfully broadcasted tx:
+        // https://explorer.solana.com/tx/66PAVjxFVGP4ctrkXmyNRhp6BdFT7gDe1k356DZzCRaBDTmJZF1ewGsbujWRjDTrt5utnz8oHZw3mg8qBNyct41w?cluster=devnet
+    }
     
     func testSignUserMessage() throws {
         let privateKey = Data(hexString: "44f480ca27711895586074a14c552e58cc52e66a58edb6c58cf9b9b7295d4a2d")!
diff --git a/tests/chains/Solana/TWSolanaTransaction.cpp b/tests/chains/Solana/TWSolanaTransaction.cpp
index 14613f3c344..f562dcfb8b4 100644
--- a/tests/chains/Solana/TWSolanaTransaction.cpp
+++ b/tests/chains/Solana/TWSolanaTransaction.cpp
@@ -10,6 +10,7 @@
 #include "Base64.h"
 #include "Base58.h"
 #include "HexCoding.h"
+#include "TransactionCompiler.h"
 
 #include <gtest/gtest.h>
 
@@ -137,4 +138,57 @@ TEST(TWSolanaTransaction, SetPriorityFee) {
     EXPECT_EQ(output.encoded(), "AVUye82Mv+/aWeU2G+B6Nes365mUU2m8iqcGZn/8kFJvw4wY6AgKGG+vJHaknHlCDwE1yi1SIMVUUtNCOm3kHg8BAAIEODI+iWe7g68B9iwCy8bFkJKvsIEj350oSOpcv4gNnv/st+6qmqipl9lwMK6toB9TiL7LrJVfij+pKwr+pUKxfwAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAwZGb+UhFzL/7K26csOb57yM5bvF9xJrLEObOkAAAAAboZ09wD3Y5HNUl7aN8bwpCqowev1hMu7fSgziLswUSgMDAAUCECcAAAICAAEMAgAAAOgDAAAAAAAAAwAJA+gDAAAAAAAA");
 }
 
+
+TEST(TWSolanaTransaction, SetFeePayer) {
+    const auto coin = TWCoinTypeSolana;
+
+    // base64 encoded
+    const auto originalTx = STRING("AQAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAACAAQABA2uEKrOPvZNBtdUtSFXcg8+kj4O/Z1Ht/hwvnaqq5s6mTXd3KtwUyJFfRs2PBfeQW8xCEZvNr/5J/Tx8ltbn0pwAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAACo+QRbvXWNKoOfaOL4cSpfYrmn/2TV+dBmct+HsmmwdAQICAAEMAgAAAACcnwYAAAAAAA==");
+
+    // Step 1 - Add fee payer to the transaction.
+    const auto feePayer = STRING("Eg5jqooyG6ySaXKbQUu4Lpvu2SqUPZrNkM4zXs9iUDLJ");
+    const auto updatedTx = WRAPS(TWSolanaTransactionSetFeePayer(originalTx.get(), feePayer.get()));
+
+    assertStringsEqual(updatedTx, "AgAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAgAIAAQTLKvCJtWpVdze8Fxjgy/Iyz1sC4U7gqnxmdSM/X2+bV2uEKrOPvZNBtdUtSFXcg8+kj4O/Z1Ht/hwvnaqq5s6mTXd3KtwUyJFfRs2PBfeQW8xCEZvNr/5J/Tx8ltbn0pwAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAACo+QRbvXWNKoOfaOL4cSpfYrmn/2TV+dBmct+HsmmwdAQMCAQIMAgAAAACcnwYAAAAAAA==");
+
+    // Step 2 - Decode transaction into a `RawMessage` Protobuf.
+    const std::string updateTxDataB64 {TWStringUTF8Bytes(updatedTx.get()) };
+    const auto updatedTxData = Base64::decode(updateTxDataB64);
+    const auto updatedTxRef = WRAPD(TWDataCreateWithBytes(updatedTxData.data(), updatedTxData.size()));
+
+    const auto decodeOutputData = WRAPD(TWTransactionDecoderDecode(TWCoinTypeSolana, updatedTxRef.get()));
+    Proto::DecodingTransactionOutput decodeOutput;
+    decodeOutput.ParseFromArray(TWDataBytes(decodeOutputData.get()), static_cast<int>(TWDataSize(decodeOutputData.get())));
+    EXPECT_EQ(decodeOutput.error(), Common::Proto::SigningError::OK);
+
+    // Step 3 - Obtain preimage hash.
+    Proto::SigningInput input;
+    *input.mutable_raw_message() = decodeOutput.transaction();
+    input.set_tx_encoding(Proto::Encoding::Base64);
+    auto inputString = input.SerializeAsString();
+    auto inputStrData = TW::Data(inputString.begin(), inputString.end());
+
+    const auto preImageHashesData = TransactionCompiler::preImageHashes(coin, inputStrData);
+    auto preSigningOutput = Proto::PreSigningOutput();
+    preSigningOutput.ParseFromArray(preImageHashesData.data(), (int)preImageHashesData.size());
+    ASSERT_EQ(preSigningOutput.signers_size(), 2);
+    auto preImageHash = preSigningOutput.data();
+    EXPECT_EQ(hex(preImageHash), "8002000104cb2af089b56a557737bc1718e0cbf232cf5b02e14ee0aa7c6675233f5f6f9b576b842ab38fbd9341b5d52d4855dc83cfa48f83bf6751edfe1c2f9daaaae6cea64d77772adc14c8915f46cd8f05f7905bcc42119bcdaffe49fd3c7c96d6e7d29c00000000000000000000000000000000000000000000000000000000000000002a3e4116ef5d634aa0e7da38be1c4a97d8ae69ffd9357e74199cb7e1ec9a6c1d01030201020c02000000009c9f060000000000");
+
+    // Step 4 - Compile transaction info.
+    // Simulate signature, normally obtained from signature server.
+    const auto feePayerSignature = parse_hex("feb9f15cc345fa156450676100033860edbe80a6f61dab8199e94fdc47678ecfdb95e3bc10ec0a7f863ab8ef5c38edae72db7e5d72855db225fd935fd59b700a");
+    const auto feePayerPublicKey = parse_hex("cb2af089b56a557737bc1718e0cbf232cf5b02e14ee0aa7c6675233f5f6f9b57");
+    const auto solSenderSignature = parse_hex("936cd6d176e701d1f748031925b2f029f6f1ab4b99aec76e24ccf05649ec269569a08ec0bd80f5fee1cb8d13ecd420bf50c5f64ae74c7afa267458cabb4e5804");
+    const auto solSenderPublicKey = parse_hex("6b842ab38fbd9341b5d52d4855dc83cfa48f83bf6751edfe1c2f9daaaae6cea6");
+
+    auto outputData = TransactionCompiler::compileWithSignatures(coin, inputStrData, {feePayerSignature, solSenderSignature}, {feePayerPublicKey, solSenderPublicKey});
+    const auto expectedTx = "Av658VzDRfoVZFBnYQADOGDtvoCm9h2rgZnpT9xHZ47P25XjvBDsCn+GOrjvXDjtrnLbfl1yhV2yJf2TX9WbcAqTbNbRducB0fdIAxklsvAp9vGrS5mux24kzPBWSewmlWmgjsC9gPX+4cuNE+zUIL9QxfZK50x6+iZ0WMq7TlgEgAIAAQTLKvCJtWpVdze8Fxjgy/Iyz1sC4U7gqnxmdSM/X2+bV2uEKrOPvZNBtdUtSFXcg8+kj4O/Z1Ht/hwvnaqq5s6mTXd3KtwUyJFfRs2PBfeQW8xCEZvNr/5J/Tx8ltbn0pwAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAACo+QRbvXWNKoOfaOL4cSpfYrmn/2TV+dBmct+HsmmwdAQMCAQIMAgAAAACcnwYAAAAAAA==";
+    Proto::SigningOutput output;
+    ASSERT_TRUE(output.ParseFromArray(outputData.data(), (int)outputData.size()));
+    EXPECT_EQ(output.encoded(), expectedTx);
+    // Successfully broadcasted tx:
+    // https://explorer.solana.com/tx/66PAVjxFVGP4ctrkXmyNRhp6BdFT7gDe1k356DZzCRaBDTmJZF1ewGsbujWRjDTrt5utnz8oHZw3mg8qBNyct41w?cluster=devnet
+}
+
 } // TW::Solana::tests