基于加解密算法框架的常见规格问题
场景描述
对于加解密在鸿蒙和安卓相互转换,以及鸿蒙安卓互调的各种场景下使用密文密钥的问题。
应用经常会遇到如下的业务诉求:
场景一:SM2加解密,安卓和鸿蒙的sm2密文,密钥格式不符,不能直接使用,需要一定的转换。
场景二:AES加解密,缺少基础的加解密示例,在原有的文档示例基础上不知道如何修改。
方案描述
场景一:
对于使用sm2加解密,安卓生成的密钥拿到鸿蒙使用如何导入,密文如何去转换、鸿蒙生成的密文如何拿到安卓去解密。
方案
1、对于传入的密钥中公钥是带04的的十六进制的130位字符串,在传入的时候,密钥参数对应的格式为 04+x+y,x和y的长度是一致的,私钥的十六进制就直接放入对应的参数即可
传入不带04的十六进制的128位字符串,对应的格式就是x+y,代码中 keyStr.startsWith("04") ? keyStr.slice(2) : keyStr正是为了判断这个。
2、对于安卓加密的密文,鸿蒙这边的格式是ASN.1包裹的格式,因此鸿蒙这边解密的时候,需要先序列化:HexStrTouint8Array(new SM2_Ciphertext().i2d_SM2_Ciphertext("安卓的密文"));同理鸿蒙生成的密文要先解码:new SM2_Ciphertext().d2i_SM2_Ciphertext(uint8ArrayToHexStr(鸿蒙密文)),其中安卓的密文为十六进制字符串,鸿蒙密文为Uint8Array数组
具体实现如下:
效果图
核心代码
根据密钥参数生成sm2私钥
export async function convertStrToPriKey(keyStr: string): Promise<cryptoFramework.PriKey> {
let sk = BigInt("0x" + keyStr)
let priKeySpec: cryptoFramework.ECCPriKeySpec = {
params: cryptoFramework.ECCKeyUtil.genECCCommonParamsSpec('NID_sm2'),
sk: sk,
algName: "SM2",
specType: cryptoFramework.AsyKeySpecType.PRIVATE_KEY_SPEC
}
let keypairGenerator = cryptoFramework.createAsyKeyGeneratorBySpec(priKeySpec)
return await keypairGenerator.generatePriKey()
}
根据密钥参数生成sm2公钥
export async function convertStrToPubKey(keyStr: string): Promise<cryptoFramework.PubKey> {
let pubKeyStr = keyStr.startsWith("04") ? keyStr.slice(2) : keyStr
let pkPart1 = pubKeyStr.slice(0, pubKeyStr.length / 2)
let pkPart2 = pubKeyStr.slice(pubKeyStr.length / 2)
let pk: cryptoFramework.Point = {
x: BigInt("0x" + pkPart1),
y: BigInt("0x" + pkPart2),
}
let pubKeySpec: cryptoFramework.ECCPubKeySpec = {
params: cryptoFramework.ECCKeyUtil.genECCCommonParamsSpec('NID_sm2'),
pk: pk,
algName: "SM2",
specType: cryptoFramework.AsyKeySpecType.PUBLIC_KEY_SPEC
}
let keypairGenerator = cryptoFramework.createAsyKeyGeneratorBySpec(pubKeySpec)
return await keypairGenerator.generatePubKey()
}
加密消息
async function encryptMessagePromise(publicKey: cryptoFramework.PubKey, plainText: string) {
let cipher = cryptoFramework.createCipher('SM2_256|SM3')
await cipher.init(cryptoFramework.CryptoMode.ENCRYPT_MODE, publicKey, null)
let encryptData = await cipher.doFinal({ data:stringToUint8Array(plainText) })
return encryptData
}
解密消息
async function decryptMessagePromise(privateKey: cryptoFramework.PriKey, cipherText: cryptoFramework.DataBlob) {
let decoder = cryptoFramework.createCipher('SM2_256|SM3')
await decoder.init(cryptoFramework.CryptoMode.DECRYPT_MODE, privateKey, null)
let decryptData = await decoder.doFinal(cipherText)
return decryptData
}
使用过程中安卓和鸿蒙的格式转换介绍
export async function test(data: string) {
//十六进制的公私钥
let pubKeyStr = "0453402B95F3584F36B9A7129A6B5C6109F2DBC7C94BE7858DB66C48AF38CB5C3B76883EE4BF18E270607191E233EAC0A95ECFB8EF6FE80C5F782DE24F018DEB5F"
let priKeyStr = "5B9270E0ADF86A101167610FCCD375A6549DC14E9225951EF3A4640F26D6CD9C"
//安卓加密后的密文
let a = "53ce193ad865c6d97742da78b18a21d0ca66200fe080284d774d5500915be2425cea2f310c9a423bc2d08ce5c1e78a75cfd66d88688a0e2076a45614307e4372aa10b514841cfe7bff08fc82d96bdf35754696571e5fbedd552d1ab7c54bff796a0e3fd72902";
//根据密钥参数生成对应的公私钥
let pk = await convertStrToPubKey(pubKeyStr)
let sk = await convertStrToPriKey(priKeyStr)
//加密
let encryptText = await encryptMessagePromise(pk, data)
//将加密的密文数据解码转换为安卓可用数据(用于鸿蒙和安卓的交接)
let b = new SM2_Ciphertext().d2i_SM2_Ciphertext(uint8ArrayToHexStr(encryptText.data))
console.log("解码后数据=======>" + b)
//解密得到结果
let res = await decryptMessagePromise(sk, encryptText)
console.log("a=======>" + uint8ArrayToString(res.data))
//针对安卓的密文处理,转成鸿蒙可用uint8Array数组数据
let c = HexStrTouint8Array(new SM2_Ciphertext().i2d_SM2_Ciphertext(a))
//对安卓生成的的密文进行解密
let resa = await decryptMessagePromise(sk, { data:c })
}
场景二:
缺少基础的加解密示例(AES|ECB|PKCS7 demo)
方案
对于不同的分组模式下表中给出了相应的参数适用说明,代码以AES128为例,这里的密钥传入的为base64格式,偏移量IV为字符串,对于格式的可以参考格式转换。对于GCM的参数设置,这里给了IV的,其余参数参考IV的写法即可。模板中使用的加解密算法以及密钥规格可以参考以下链接:
分组模式 | 适用的加解密方式 | 所需参数 | 备注 |
ECB | AES、SM4、3DES | 没有偏移量等参数 | |
CBC、CTR、OFB、CFB | AES、SM4、3DES(不支持CTR) | 指明加解密参数iv。 - AES的iv长度为16字节 - 3DES的iv长度为8字节 - SM4iv长度为16字节。 | |
GCM | AES | 指明加解密参数iv,长度为1~16字节,常用为12字节。 指明加解密参数aad,长度为0~INT_MAX字节,常用为16字节。 指明加解密参数authTag,长度为16字节。 | 在GCM模式下,需要从加密后的数据中取出末尾16字节,作为解密时初始化的认证信息 |
效果图
核心代码
ECB加解密模板
//加密
async function aesEncrypt(text:string,puKey:string): Promise<string>{
let globalResult = ""
try {
//这里已AES加解密为例支持AES、SM4、3DES
let cipherAlgName = 'AES128|ECB|PKCS7';
// 创建加解密对象
let globalCipher = cryptoFramework.createCipher(cipherAlgName);
//这里已AES加解密为例支持AES、SM4、3DES
let symAlgName = 'AES128';
//创建密钥对象
let symKeyGenerator = cryptoFramework.createSymKeyGenerator(symAlgName);
//将传入的base格式的密钥转为Uint8Array数组
let dataUint8Array = base.decodeSync(puKey)
let keyBlob: cryptoFramework.DataBlob = { data: dataUint8Array }
//导入外部密钥
let promiseSymKey = await symKeyGenerator.convertKey(keyBlob)
//初始化
await globalCipher.init(cryptoFramework.CryptoMode.ENCRYPT_MODE, promiseSymKey, null);
//加密
let result = await globalCipher.doFinal({data:stringToUint8Array(text)})
//将加密结果转换为base64格式,用于保存或者传递
globalResult = base.encodeToStringSync(result.data);
} catch (err) {
console.log(err.message)
}
return globalResult;
}
// 解密
async function aesDecrypt(text: string, key: string) {
let globalResult = ""
try {
//这里已AES加解密为例支持AES、SM4、3DES
let cipherAlgName = 'AES128|ECB|PKCS7';
// 创建加解密对象
let globalCipher = cryptoFramework.createCipher(cipherAlgName);
//这里已AES加解密为例支持AES、SM4、3DES
let symAlgName = 'AES128';
//创建密钥对象
let symKeyGenerator = cryptoFramework.createSymKeyGenerator(symAlgName);
//将传入的base格式的密钥转为Uint8Array数组
let dataUint8Array = base.decodeSync(key)
let keyBlob: cryptoFramework.DataBlob = { data: dataUint8Array }
//导入外部密钥
let promiseSymKey = await symKeyGenerator.convertKey(keyBlob)
await globalCipher.init(cryptoFramework.CryptoMode.DECRYPT_MODE, promiseSymKey, null);
let plainText: cryptoFramework.DataBlob = { data: base.decodeSync(text) }
let result = await globalCipher.doFinal(plainText)
//将解密后的结果result解码之后得到明文
globalResult = uint8ArrayToString(result.data);
console.log("解密后的明文==》" + globalResult)
} catch (err) {
console.log(err.message)
}
}
CBC加解密模板
//加密
async function aesEncrypt(text: string, key: string, iv:string): Promise<string> {
let globalResult = ""
try {
//这里已AES加解密为例支持AES、SM4、3DES
let cipherAlgName = 'AES128|CBC|PKCS7';
let globalCipher = cryptoFramework.createCipher(cipherAlgName);
//这里已AES加解密为例支持AES、SM4、3DES
let symAlgName = 'AES128';
let symKeyGenerator = cryptoFramework.createSymKeyGenerator(symAlgName);
let dataUint8Array = base.decodeSync(key)
let keyBlob: cryptoFramework.DataBlob = { data: dataUint8Array }
let promiseSymKey = await symKeyGenerator.convertKey(keyBlob)
let ivData = stringToUint8Array(iv);
let ivdata: cryptoFramework.DataBlob = { data: ivData }; //偏移
let iv: cryptoFramework.IvParamsSpec = { iv: ivdata, algName: 'IvParamsSpec' } //cbc 模式的参数
await globalCipher.init(cryptoFramework.CryptoMode.ENCRYPT_MODE, promiseSymKey, iv);
let plainText: cryptoFramework.DataBlob = { data: this.stringToUint8Array(text) }
let result = await globalCipher.doFinal(plainText)
globalResult = base.encodeToStringSync(result.data);
} catch (err) {
console.log(err.message)
}
return globalResult;
}
// 解密
async function aesDecrypt(text: string, key: string,iv:string) {
let globalResult = ""
try {
let cipherAlgName = 'AES128|CBC|PKCS7';
let globalCipher = cryptoFramework.createCipher(cipherAlgName);
let symAlgName = 'AES128';
let symKeyGenerator = cryptoFramework.createSymKeyGenerator(symAlgName);
let dataUint8Array = base.decodeSync(key)
let keyBlob: cryptoFramework.DataBlob = { data: dataUint8Array }
let promiseSymKey = await symKeyGenerator.convertKey(keyBlob)
// /*设置偏移量 */
let ivData = stringToUint8Array(iv);
let ivdata: cryptoFramework.DataBlob = { data: ivData }; //偏移
let iv: cryptoFramework.IvParamsSpec = { iv: ivdata, algName: 'IvParamsSpec' } //cbc 模式的参数
await globalCipher.init(cryptoFramework.CryptoMode.DECRYPT_MODE, promiseSymKey, globalCbcParams);
let plainText: cryptoFramework.DataBlob = { data: base.decodeSync(text) }
let result = await globalCipher.doFinal(plainText)
globalResult = uint8ArrayToString(result.data);
console.log("解密后的明文==》" + globalResult)
} catch (err) {
console.log(err.message)
}
return globalResult;
}
GCM加解密模板
//GCM的参数设置
function genGcmParamsSpec() {
let arr = [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0]; // 12 bytes
let dataIv = new Uint8Array(arr);
let ivBlob: cryptoFramework.DataBlob = { data: dataIv };
arr = [0, 0, 0, 0, 0, 0, 0, 0]; // 8 bytes
let dataAad = new Uint8Array(arr);
let aadBlob: cryptoFramework.DataBlob = { data: dataAad };
arr = [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0]; // 16 bytes
let dataTag = new Uint8Array(arr);
let tagBlob: cryptoFramework.DataBlob = {
data: dataTag
};
// GCM的authTag在加密时从doFinal结果中获取,在解密时填入init函数的params参数中
let gcmParamsSpec: cryptoFramework.GcmParamsSpec = {
iv: ivBlob,
aad: aadBlob,
authTag: tagBlob,
algName: "GcmParamsSpec"
};
return gcmParamsSpec;
}
//加密
export async function aesEncryptGCM(text: string, key: string,iv:string): Promise<string> {
let globalResult = ""
try {
let cipherAlgName = 'AES128|GCM|PKCS5';
let globalCipher = cryptoFramework.createCipher(cipherAlgName);
let symAlgName = 'AES128';
let symKeyGenerator = cryptoFramework.createSymKeyGenerator(symAlgName);
let dataUint8Array = stringToUint8Array(key)
let keyBlob: cryptoFramework.DataBlob = { data: dataUint8Array }
let promiseSymKey = await symKeyGenerator.convertKey(keyBlob)
let getParamsSpec: cryptoFramework.GcmParamsSpec = genGcmParamsSpec();
getParamsSpec.iv = { data: stringToUint8Array(iv) }
await globalCipher.init(cryptoFramework.CryptoMode.ENCRYPT_MODE, promiseSymKey, getParamsSpec);
let plainText: cryptoFramework.DataBlob = { data: stringToUint8Array(text) }
let res = await globalCipher.doFinal(plainText)
authTag = res.data.subarray(res.data.length - 16, res.data.length)//authTag
let a = res.data.subarray(0, res.data.length - authTag.length);//密文
globalResult = base.encodeToStringSync(a);
} catch (err) {
console.log(err.message)
}
return globalResult;
}
// 解密
export async function aesDecryptGCM(text: string, key: string) {
let globalResult = ""
try {
let cipherAlgName = 'AES128|GCM|PKCS5';
let globalCipher = cryptoFramework.createCipher(cipherAlgName);
let symAlgName = 'AES128';
let symKeyGenerator = cryptoFramework.createSymKeyGenerator(symAlgName);
let dataUint8Array = stringToUint8Array(key)
let keyBlob: cryptoFramework.DataBlob = { data: dataUint8Array }
let promiseSymKey = await symKeyGenerator.convertKey(keyBlob)
let getParamsSpec: cryptoFramework.GcmParamsSpec = genGcmParamsSpec();
getParamsSpec.authTag = {data:authTag}
getParamsSpec.iv = { data: stringToUint8Array(iv) }
await globalCipher.init(cryptoFramework.CryptoMode.DECRYPT_MODE, promiseSymKey, getParamsSpec);
let plainText: cryptoFramework.DataBlob = { data: base.decodeSync(text) }
let result = await globalCipher.doFinal(plainText)
globalResult = uint8ArrayToString(result.data);
console.log("解密后的明文==》" + globalResult)
} catch (err) {
console.log(err.message)
}
return globalResult;
}