1 files changed, 155 insertions, 0 deletions
diff --git a/MediaBrowser.Common/Cryptography/PasswordHash.cs b/MediaBrowser.Common/Cryptography/PasswordHash.cs
new file mode 100644
index 000000000..5b28d344f
--- /dev/null
+++ b/MediaBrowser.Common/Cryptography/PasswordHash.cs
@@ -0,0 +1,155 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Text;
+using static MediaBrowser.Common.HexHelper;
+
+namespace MediaBrowser.Common.Cryptography
+{
+    // Defined from this hash storage spec
+    // https://github.com/P-H-C/phc-string-format/blob/master/phc-sf-spec.md
+    // $<id>[$<param>=<value>(,<param>=<value>)*][$<salt>[$<hash>]]
+    // with one slight amendment to ease the transition, we're writing out the bytes in hex
+    // rather than making them a BASE64 string with stripped padding
+    public class PasswordHash
+    {
+        private readonly Dictionary<string, string> _parameters;
+
+        public PasswordHash(string id, byte[] hash)
+            : this(id, hash, Array.Empty<byte>())
+        {
+
+        }
+
+        public PasswordHash(string id, byte[] hash, byte[] salt)
+            : this(id, hash, salt, new Dictionary<string, string>())
+        {
+
+        }
+
+        public PasswordHash(string id, byte[] hash, byte[] salt, Dictionary<string, string> parameters)
+        {
+            Id = id;
+            Hash = hash;
+            Salt = salt;
+            _parameters = parameters;
+        }
+
+        /// <summary>
+        /// Gets the symbolic name for the function used.
+        /// </summary>
+        /// <value>Returns the symbolic name for the function used.</value>
+        public string Id { get; }
+
+        /// <summary>
+        /// Gets the additional parameters used by the hash function.
+        /// </summary>
+        /// <value></value>
+        public IReadOnlyDictionary<string, string> Parameters => _parameters;
+
+        /// <summary>
+        /// Gets the salt used for hashing the password.
+        /// </summary>
+        /// <value>Returns the salt used for hashing the password.</value>
+        public byte[] Salt { get; }
+
+        /// <summary>
+        /// Gets the hashed password.
+        /// </summary>
+        /// <value>Return the hashed password.</value>
+        public byte[] Hash { get; }
+
+        public static PasswordHash Parse(string storageString)
+        {
+            string[] splitted = storageString.Split('$');
+            // The string should at least contain the hash function and the hash itself
+            if (splitted.Length < 3)
+            {
+                throw new ArgumentException("String doesn't contain enough segments", nameof(storageString));
+            }
+
+            // Start at 1, the first index shouldn't contain any data
+            int index = 1;
+
+            // Name of the hash function
+            string id = splitted[index++];
+
+            // Optional parameters
+            Dictionary<string, string> parameters = new Dictionary<string, string>();
+            if (splitted[index].IndexOf('=') != -1)
+            {
+                foreach (string paramset in splitted[index++].Split(','))
+                {
+                    if (string.IsNullOrEmpty(paramset))
+                    {
+                        continue;
+                    }
+
+                    string[] fields = paramset.Split('=');
+                    if (fields.Length != 2)
+                    {
+                        throw new InvalidDataException($"Malformed parameter in password hash string {paramset}");
+                    }
+
+                    parameters.Add(fields[0], fields[1]);
+                }
+            }
+
+            byte[] hash;
+            byte[] salt;
+            // Check if the string also contains a salt
+            if (splitted.Length - index == 2)
+            {
+                salt = FromHexString(splitted[index++]);
+                hash = FromHexString(splitted[index++]);
+            }
+            else
+            {
+                salt = Array.Empty<byte>();
+                hash = FromHexString(splitted[index++]);
+            }
+
+            return new PasswordHash(id, hash, salt, parameters);
+        }
+
+        private void SerializeParameters(StringBuilder stringBuilder)
+        {
+            if (_parameters.Count == 0)
+            {
+                return;
+            }
+
+            stringBuilder.Append('$');
+            foreach (var pair in _parameters)
+            {
+                stringBuilder.Append(pair.Key);
+                stringBuilder.Append('=');
+                stringBuilder.Append(pair.Value);
+                stringBuilder.Append(',');
+            }
+
+            // Remove last ','
+            stringBuilder.Length -= 1;
+        }
+
+        /// <inheritdoc />
+        public override string ToString()
+        {
+            var str = new StringBuilder();
+            str.Append('$');
+            str.Append(Id);
+            SerializeParameters(str);
+
+            if (Salt.Length != 0)
+            {
+                str.Append('$');
+                str.Append(ToHexString(Salt));
+            }
+
+            str.Append('$');
+            str.Append(ToHexString(Hash));
+
+            return str.ToString();
+        }
+    }
+}