v1.3.0 Support long string encryption and decryption.

stulzq · Jul 9, 2019 · 9e5d930 · 9e5d930
1 parent e5d84ee
commit 9e5d930
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Showing 3 changed files with 91 additions and 19 deletions.
diff --git a/XC.RSAUtil.Test/Program.cs b/XC.RSAUtil.Test/Program.cs
@@ -1,4 +1,6 @@
 using System;
+using System.Security.Cryptography;
+using System.Text;
 
 namespace XC.RSAUtil.Test
 {
@@ -19,6 +21,13 @@ static void Main(string[] args)
             Console.WriteLine("public key pkcs1->xml:");
             Console.WriteLine(RsaKeyConvert.PublicKeyPemToXml(publicKey));
 
+            var bigDataRsa=new RsaPkcs1Util(Encoding.UTF8, publicKey,privateKey,2048);
+            var str = bigDataRsa.EncryptBigData("abcdefg", 3, "$", RSAEncryptionPadding.Pkcs1);
+            Console.WriteLine("Big Data Encrypt:");
+            Console.WriteLine(str);
+            Console.WriteLine("Big Data Decrypt:");
+            Console.WriteLine(string.Join("", bigDataRsa.DecryptBigData(str, "$", RSAEncryptionPadding.Pkcs1)));
+
             Console.ReadKey();
         }
     }

diff --git a/XC.RSAUtil/RSAUtilBase.cs b/XC.RSAUtil/RSAUtilBase.cs
@@ -27,13 +27,52 @@ public string Encrypt(string data, RSAEncryptionPadding padding)
 			return Convert.ToBase64String(resBytes);
 		}
 
-		/// <summary>
-		/// RSA private key is decrypted
-		/// </summary>
-		/// <param name="data">Need to decrypt the data</param>
-		/// <param name="padding">Padding algorithm</param>
-		/// <returns></returns>
-		public string Decrypt(string data, RSAEncryptionPadding padding)
+        /// <summary>
+        /// [Not recommended] RSA public key split encryption
+        /// <para>RSA encryption does not support too large data. In this case, symmetric encryption should be used, and RSA is used to encrypt symmetrically encrypted passwords.</para>
+        /// </summary>
+        /// <param name="data">Need to encrypt data</param>
+        /// <param name="splitLength">data split length</param>
+        /// <param name="connChar">Encrypted result link character</param>
+        /// <param name="padding">Padding algorithm</param>
+        /// <returns></returns>
+        public string EncryptBigData(string data,int splitLength,string connChar, RSAEncryptionPadding padding)
+        {
+            var sb=new StringBuilder();
+            if (splitLength >= data.Length)
+            {
+                throw new ArgumentOutOfRangeException(nameof(splitLength), "Split length cannot exceed the data length.");
+            }
+
+            var splitsNumber = Convert.ToInt32(Math.Ceiling(data.Length * 1.0 / splitLength));
+
+            var pointer = 0;
+            for (int i = 0; i < splitsNumber; i++)
+            {
+                string currentStr;
+                if (data.Length < pointer + splitLength)
+                {
+                    currentStr = data.Substring(pointer, data.Length-pointer);
+                }
+                else
+                {
+                    currentStr = data.Substring(pointer, splitLength);
+                }
+
+                sb.Append(Encrypt(currentStr, padding)+connChar);
+                pointer += splitLength;
+            }
+
+            return sb.ToString();
+        }
+
+        /// <summary>
+        /// RSA private key  decrypted
+        /// </summary>
+        /// <param name="data">Need to decrypt the data</param>
+        /// <param name="padding">Padding algorithm</param>
+        /// <returns></returns>
+        public string Decrypt(string data, RSAEncryptionPadding padding)
 		{
 			if (PrivateRsa == null)
 			{
@@ -44,14 +83,39 @@ public string Decrypt(string data, RSAEncryptionPadding padding)
 			return DataEncoding.GetString(resBytes);
 		}
 
-		/// <summary>
-		/// Use private key for data signing
-		/// </summary>
-		/// <param name="data">Need to sign data</param>
-		/// <param name="hashAlgorithmName">Signed hash algorithm name</param>
-		/// <param name="padding">Signature padding algorithm</param>
-		/// <returns></returns>
-		public string SignData(string data, HashAlgorithmName hashAlgorithmName, RSASignaturePadding padding)
+        /// <summary>
+        /// [Not recommended] RSA private key split decrypted
+        /// <para>RSA encryption does not support too large data. In this case, symmetric encryption should be used, and RSA is used to encrypt symmetrically encrypted passwords.</para>
+        /// </summary>
+        /// <param name="connChar">Encrypted result link character</param>
+        /// <param name="data">Need to decrypt the data</param>
+        /// <param name="padding">Padding algorithm</param>
+        /// <returns></returns>
+        public string[] DecryptBigData(string data,string connChar, RSAEncryptionPadding padding)
+        {
+            if (PrivateRsa == null)
+            {
+                throw new ArgumentException("private key can not null");
+            }
+
+            var splitsData = data.Split(new[] {connChar}, StringSplitOptions.RemoveEmptyEntries);
+            var result = new string[splitsData.Length];
+            for (int i = 0; i < splitsData.Length; i++)
+            {
+                result[i] = Decrypt(splitsData[i], padding);
+            }
+
+            return result;
+        }
+
+        /// <summary>
+        /// Use private key for data signing
+        /// </summary>
+        /// <param name="data">Need to sign data</param>
+        /// <param name="hashAlgorithmName">Signed hash algorithm name</param>
+        /// <param name="padding">Signature padding algorithm</param>
+        /// <returns></returns>
+        public string SignData(string data, HashAlgorithmName hashAlgorithmName, RSASignaturePadding padding)
 		{
 		    var res = SignDataGetBytes(data, hashAlgorithmName, padding);
             return Convert.ToBase64String(res);

diff --git a/XC.RSAUtil/XC.RSAUtil.csproj b/XC.RSAUtil/XC.RSAUtil.csproj
@@ -1,4 +1,4 @@
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
     <TargetFramework>netstandard2.0</TargetFramework>
@@ -10,9 +10,8 @@
     <PackageLicenseUrl>https://github.com/stulzq/RSAUtil/blob/master/LICENSE</PackageLicenseUrl>
     <PackageRequireLicenseAcceptance>true</PackageRequireLicenseAcceptance>
     <PackageTags>RSA,RSA Xml,RSA Pkcs1,RSA Pkcs8,RSA Convert,RSA Format,Pem,RSAUtil,RSAHelper</PackageTags>
-    <Version>1.2.0</Version>
-    <AssemblyVersion>1.2.0.0</AssemblyVersion>
-    <FileVersion>1.2.0.0</FileVersion>
+    <Version>1.3.0</Version>
+    <PackageReleaseNotes>Support long string encryption and decryption.</PackageReleaseNotes>
   </PropertyGroup>
 
   <ItemGroup>