na-get-lib/NaGet.Packages/HashValue.cs

   1 using System;\r
   2 using System.IO;\r
   3 using System.Xml.Serialization;\r
   4 using System.Security.Cryptography;\r
   5 \r
   6 namespace NaGet.Packages\r
   7 {\r
   8         /// <summary>\r
   9         /// ハッシュ値の種類(計算法)を表す。\r
  10         /// </summary>\r
  11         public enum HashValueType\r
  12         {\r
  13                 [XmlEnum(Name="size")]\r
  14                 SIZE,\r
  15                 [XmlEnum(Name="md5")]\r
  16                 MD5SUM,\r
  17                 [XmlEnum(Name="sha1")]\r
  18                 SHA1SUM,\r
  19                 [XmlEnum(Name="sha256")]\r
  20                 SHA256SUM\r
  21         }\r
  22         \r
  23         public class HashValue\r
  24         {\r
  25                 /// <summary>\r
  26                 /// ハッシュ値の種類(計算法)\r
  27                 /// </summary>\r
  28                 [XmlAttribute]\r
  29                 public HashValueType Type;\r
  30                 \r
  31                 /// <summary>\r
  32                 /// ハッシュ値そのものをあらわす\r
  33                 /// </summary>\r
  34                 [XmlText]\r
  35                 public string Value;\r
  36                 \r
  37                 /// <summary>\r
  38                 /// コンストラクタ\r
  39                 /// </summary>\r
  40                 public HashValue()\r
  41                 {\r
  42                 }\r
  43                 \r
  44                 /// <summary>\r
  45                 /// 与えられたファイルのハッシュ値が同一であるか検証する\r
  46                 /// </summary>\r
  47                 /// <param name="path">ハッシュ計算を行う対象のファイル</param>\r
  48                 /// <returns>ファイルのハッシュ値が妥当な場合true。</returns>\r
  49                 public bool Validate(string path)\r
  50                 {\r
  51                         return string.Compare(this.Value, HashValueFor(path, this.Type), true) == 0;\r
  52                 }\r
  53                 \r
  54                 /// <summary>\r
  55                 /// ファイルのハッシュを計算する\r
  56                 /// </summary>\r
  57                 /// <param name="file">計算対象のファイル</param>\r
  58                 /// <param name="type">ハッシュの種類(計算法)</param>\r
  59                 /// <returns></returns>\r
  60                 public static string HashValueFor(string file, HashValueType type)\r
  61                 {\r
  62                         using (FileStream fs = new FileStream(file, FileMode.Open)) {\r
  63                                 return HashValue.HashValueFor(fs, type);\r
  64                         }\r
  65                 }\r
  66                 \r
  67                 /// <summary>\r
  68                 /// ストリーム入力からハッシュを計算する\r
  69                 /// </summary>\r
  70                 /// <param name="stream">ストリーム入力</param>\r
  71                 /// <param name="type">ハッシュの種類(計算法)</param>\r
  72                 /// <returns></returns>\r
  73                 public static string HashValueFor(Stream stream, HashValueType type)\r
  74                 {\r
  75                         byte[] hash;\r
  76                         \r
  77                         switch (type) {\r
  78                                 case HashValueType.SIZE:\r
  79                                         return stream.Length.ToString();\r
  80                                 case HashValueType.MD5SUM:\r
  81                                         hash = MD5.Create().ComputeHash(stream);\r
  82                                         break;\r
  83                                 case HashValueType.SHA1SUM:\r
  84                                         hash = SHA1.Create().ComputeHash(stream);\r
  85                                         break;\r
  86                                 case HashValueType.SHA256SUM:\r
  87                                         hash = SHA256.Create().ComputeHash(stream);\r
  88                                         break;\r
  89                                 default:\r
  90                                         throw new NotSupportedException(string.Format("Hash type {0} does not supported", type));\r
  91                         }\r
  92                         \r
  93                         return BitConverter.ToString(hash).Replace("-",string.Empty);\r
  94                 }\r
  95         }\r
  96 }\r