交易签名

可拆分成两部分：基础数据 & 实际签名。

基础数据有：手续费、被锁高度等。

实际签名有：公钥、签名等。

The excess value is a multisig of all the input owners and all the output owners.

/// A proof that a transaction sums to zero. Includes both the transaction's
/// Pedersen commitment and the signature, that guarantees that the commitments
/// amount to zero.
/// The signature signs the fee and the lock_height, which are retained for
/// signature validation.
#[derive(Serialize, Deserialize, Debug, Clone)]
pub struct TxKernel {
    /// Options for a kernel's structure or use
    pub features: KernelFeatures,
    /// Fee originally included in the transaction this proof is for.
    pub fee: u64,
    /// This kernel is not valid earlier than lock_height blocks
    /// The max lock_height of all *inputs* to this transaction
    pub lock_height: u64,
    /// Remainder of the sum of all transaction commitments. If the transaction
    /// is well formed, amounts components should sum to zero and the excess
    /// is hence a valid public key.
    pub excess: Commitment, // 相当于公钥（可由 Output 而来）
    /// The signature proving the excess is a valid public key, which signs
    /// the transaction fee.
    pub excess_sig: Signature, # 包含了 TxKernel 下面的其它 4 个元素，相当于签名
}

The excess value is a multisig but it's also a proof that the transaction adds up to zero at the same time.

excess_sig

签名。

用公钥针对消息进行签名的结果，针对 TxKernel 下面的其它 4 个元素（并不是“空字符串”）。

excess

公钥。

交易有 offset: BlindingFactor，由接受方随机选择，它对应 k = k1 + k2 这里的 k2

excess 对应 k1G

作用有：

• 做为公钥
• 做为见证

由 fees commit 和 output commit 两者相加得到。

TxKernelEntry

/// Wrapper around a tx kernel used when maintaining them in the MMR.
#[derive(Serialize, Deserialize, Debug, Clone)]
pub struct TxKernelEntry {
    /// The underlying tx kernel.
    pub kernel: TxKernel,
}

作用

• 元数据
• 见证&签名
• Trust model

verify 验证

这里特指密码学上的验证。

    /// Verify the transaction proof validity. Entails handling the commitment
    /// as a public key and checking the signature verifies with the fee as
    /// message.

fee 和 lock_height 做为消息，excess_sig 做为签名，excess 做为公钥，用的是 secp 相关算法。

上面几个要素，已经完全符合密码学里“验证”条件。