> For the complete documentation index, see [llms.txt](https://relationlabs.gitbook.io/protocol/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://relationlabs.gitbook.io/protocol/protocol-zh/contract-open-standard/publication/privacy.md).
# Privacy Content
基于Semantic SBT和[Lit Protocol](https://developer.litprotocol.com/sdk/explanation/encryption/#encrypting)实现隐私数据分享，用户可以给满足指定条件的地址分享自己的隐私数据。
使用Lit Protocol对数据进行加密与解密，[Arweave](https://www.arweave.org/)存储密文、加密后的密钥以及分享条件，Semantic SBT用于存储arweave的哈希以及定义分享条件。
分享的条件可以设置成：
* EOA地址
* 拥有特定集合NFT的用户
* 拥有特定SBT的用户
* 拥有一定 ERC20 代币余额的用户
## Schema
隐私数据分享的[schema模版](https://arweave.net/DeM6LRONjAUYr3qixkguLuFvYSHkykN7ZRKHn2HR5Gs)，schema以ttl文件的形式保存至Arweave，交易哈希将作为schemaURI，在初始化合约时传入，参数示例：
```
ar://DeM6LRONjAUYr3qixkguLuFvYSHkykN7ZRKHn2HR5Gs
```
schema由以下三部分组成：
* schema 前缀列表
```
PREFIX :
PREFIX p:
PREFIX rdf:
PREFIX xsd:
PREFIX rdfs:
```
* Class
Soul用于表示地址实体
```
:Soul a rdfs:Class ;
rdfs:label "Soul" ;
rdfs:comment "A soul." .
```
* Predicate
谓词`p:privacyData`表述隐私数据
```
p:privacyContent a rdf:Property ;
rdfs:label "privacyContent" ;
rdfs:comment "The privacy content." ;
rdfs:domain :Soul ;
rdfs:range xsd:string .
```
## 合约
```solidity
interface IPrivacyContent is ISemanticSBT {
/**
* 预生成tokenId
* @return tokenId 预生成的tokenId
*/
function prepareToken() external returns (uint256);
/**
* 查询持有的预生成tokenId
* @param owner 被查询的地址
* @return tokenId 预生成的tokenId
*/
function ownedPrepareToken(address owner) external view returns (uint256);
/**
* 发布内容
* @param content 发布的内容对应的Arweave交易哈希，可通过此交易哈希访问到原始发布内容
*/
function post(string memory content) external;
/**
* 是否具备token的查看权限
* @param viewer 查看者的地址
* @param tokenId 发布的内容对应tokenId
* @param isViewer true--具备查看权限；false--不具备查看权限
*/
function isViewerOf(address viewer, uint256 tokenId) external view returns (bool);
/**
* 查询发布内容
* @param tokenId
* @return content 发布的内容对应的Arweave交易哈希，可通过此交易哈希访问到原始发布内容
*/
function contentOf(uint256 tokenId) external view returns (string memory);
}
```
完整的实现合约代码可访问：
* [PrivacyContent](https://github.com/relationlabs/semanticSBT/blob/main/contracts/template/PrivacyContent.sol)
## 隐私数据分享流程
### 加密
将待分享的隐私数据，通过[Lit Protocol](https://developer.litprotocol.com/sdk/explanation/encryption/#encrypting)进行加密，并将加密结果（accessCondition、encryptedSymmetricKey、encryptedObject）封装成encryptMetaDada上传至存储层(arweave等)，得到encryptMetaDada的地址。
* encryptMetaDada格式如下：
```json
{
"encryptionBy": "lit-protocol",
"accessCondition": [
{
"contractAddress": "${contract address of Semantic SBT}",
"standardContractType": "ERC721",
"chain": "polygon",
"method": "isViewerOf",
"parameters": [
":userAddress",
"${tokenId}"
],
"returnValueTest": {
"comparator": "=",
"value": true
}
}
],
"encryptedSymmetricKey": "a hex string that LIT will use to decrypt your content as long as you satisfy the conditions",
// encrypted content
"encryptedObject": "AhgXUao1QU2iQg34UsCw0-ptkoy_fhifEoqEs3_Zj1s="
}
```
### Mint隐私SBT
基于Semantic SBT规范实现一个PrivacySemanticSBT合约，mint一个带隐私数据的SBT。其中该SBT的RDF中的object为arweave/ipfs的地址。
* SemanticSBTPrivacy合约方法调用流程
```javascript
import {ethers, providers} from 'ethers'
const accounts = await ethereum.request({method: 'eth_requestAccounts'})
await PrivacySemanticSBT.prepareTokenId();
const tokenId = await PrivacySemanticSBT.ownedPrepareToken(accounts[0]);
//Mint SBT
PrivacySemanticSBT.mintWithPrivacy(tokenId, arweaveHash);
//添加viewer
await PrivacySemanticSBT.addViewer(address1, tokenId);
```
* 完整的RDF示例如下：
```
:Soul_0x0000000000000000000000000000000000000000 p:privacyContent "ar://djbZ5l5Ij5zBEgFFnVlDDqa4z5ACtS_A9uWPmAVwRe"
```
* encryptedObject的组成
* web3存储系统，比如: `ar://` 或 `ipfs://`
* web3存储的哈希
* encryptedObject示例：
```
ar://djbZ5l5Ij5zBEgFFnVlDDqa4z5ACtS_A9uWPmAVwRe
```
### 解密
解密方从SBT的object中获取encryptMetaDada。调用[LitProtocol的解密方法](https://developer.litprotocol.com/sdk/explanation/encryption/#decrypting)，即可解密得到明文的object。
## AccessConditions
允许设置不同类型的访问条件，来控制用户访问隐私数据。
### 用户拥有特定的钱包地址
如果解密者拥有指定的钱包地址，则有权限解密隐私数据。
```
[
{
"contractAddress": "",
"standardContractType": "",
"chain": "ethereum",
"method": "",
"parameters": [
":userAddress",
],
"returnValueTest": {
"comparator": "=",
"value": "0x50e2dac5e78B5905CB09495547452cEE64426db2"
}
}
]
```
### 用户持有NFT集合的token
如果解密者拥有指定NFT集合的token，则有权限解密隐私数据。
```
[
{
"contractAddress": "0x3110c39b428221012934A7F617913b095BC1078C",
"standardContractType": "ERC721",
"chain": "ethereum",
"method": "balanceOf",
"parameters": [ ":userAddress" ],
"returnValueTest": { "comparator": ">", "value": "0" }
}
]
```
#### 用户持有NFT集合的Token
如果解密者拥有指定SBT集合的token，则有权限解密隐私数据。
```
[
{
"contractAddress": "0x588368698213bdf05aa722936d7657df8f3abe27",
"standardContractType": "ERC721",
"chain": "polygon",
"method": "balanceOf",
"parameters": [ ":userAddress" ],
"returnValueTest": { "comparator": ">", "value": "0" }
}
]
```
### 用户持有至少XX个ERC20 Token
如果解密者拥有指定数量的ERC20token，则有权限解密隐私数据。
```
[
{
"contractAddress": "0x9f8F72aA9304c8B593d555F12eF6589cC3A579A2",
"standardContractType": "ERC20",
"chain": "ethereum",
"method": "balanceOf",
"parameters": [
":userAddress"
],
"returnValueTest": {
"comparator": ">",
"value": "0"
}
}
]
```
### 可以使用AND或OR任意组合上述条件
```json
[
{
"contractAddress": "0x9f8F72aA9304c8B593d555F12eF6589cC3A579A2",
"standardContractType": "ERC20",
"chain": "ethereum",
"method": "balanceOf",
"parameters": [
":userAddress"
],
"returnValueTest": {
"comparator": ">",
"value": "0"
}
},
{
"operator": "or"
},
{
"contractAddress": "0x3110c39b428221012934A7F617913b095BC1078C",
"standardContractType": "ERC721",
"chain": "ethereum",
"method": "balanceOf",
"parameters": [
":userAddress"
],
"returnValueTest": {
"comparator": ">",
"value": "0"
}
}
]
```