1using System;
2using System.Collections.Specialized;
3using System.Configuration;
4using System.Security.Principal;
5using System.Threading;
6using System.Web.Configuration;
7
8namespace Enterprise.Security
9{
10    /// <!-- 
11    ///     Code Courtesy Of http://www.purecoding.net
12    ///     Permissions : Free for general use
13    ///     Keywords: Security, Identity, c#, .Net, Aspnet. 
14    ///     Filename: ApplicationSecurity.cs
15    /// -->
16
17    #region Role Enumeration
18
19    /// <summary>
20    /// This enum defines the application level roles.  Each one will be mapped to 
21    /// 1 or more security group(s) on the network.  <see cref="ApplicationSecurity"/> for more information.
22    /// </summary>
23    [Flags]
24    public enum ApplicationRole
25    {
26        Role_User = 1,
27        Role_Editor = 2
28        //Role_Administrator = 4
29        /* Additional Roles and bit flags
30         * Role_ = 4
31         * Role_ = 8
32         * Role_ = 16
33         * Role_ = 32
34         */
35
36    }
37
38    #endregion
39
40    /// <summary>
41    /// This class implements a Role Based security model for use in ASP.Net 2.0
42    /// The Roles are defined in the <see cref="ApplicationRole"/> enum.  The name
43    /// of each enum item must also exist in the web.config.  
44    /// The web.config contains a section that is used to map the ApplicationRole to a 
45    /// real security group on the network or local computer.
46    /// Usage (Single Role): if(IsInRole(Role_Editor)) { //Permission granted... }
47    /// Usage (Multiple Roles): if(IsInAnyRole(Role_Administrator | Role_Editor)) { //Permission granted... }
48    /// Usage (Multiple Roles): if(IsInAllRoles(Role_Administrator | Role_Editor)) { //Permission granted... }
49    /// </summary>
50    /// <remarks>You can specify multiple domain or local security 
51    /// groups by using a semi colon seperated list.</remarks>
52    // Note: In the web.config you need the following:
53    //<configuration>
54    //<configSections>
55    //  <section 
56    //      name="securityRoleMappings" 
57    //      type="System.Configuration.AppSettingsSection, 
58    //      System.Configuration, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a" 
59    //      restartOnExternalChanges="true" 
60    //      requirePermission="false" />
61    //</configSections>
62    //<securityRoleMappings>
63    //  <add key="Role_Editor" value="MyDomain\ABC-Editors;MyDomain\Admins;" />
64    //  <add key="Role_User" value="MyDomain\ABC-Users" />
65    //</securityRoleMappings>
66    public sealed class ApplicationSecurity
67    {
68        #region private constants and constructor
69
70        private static readonly string _ConfigSectionName = "securityRoleMappings";
71
72        private ApplicationSecurity()
73        {
74        }
75
76        #endregion
77
78        #region User Information
79
80        public static string UserLogonName
81        {
82            get { return GetUserName(); }
83        }
84
85        public static WindowsIdentity CurrentIdentity
86        {
87            get { return GetCurrentUser(); }
88        }
89
90        public static bool IsAnonymous
91        {
92            get { return GetCurrentUser().IsAnonymous; }
93        }
94
95        #endregion
96
97        #region public methods
98
99        /// <summary>
100        /// Checks to see if a user is within a pre defined role.
101        /// You must pass a single role to this function or it will error.
102        /// To check multiple roles at once with a bitwise operation use <see cref="IsInAnyRole"/>
103        /// or <see cref="IsInAllRoles"/>.
104        /// </summary>
105        /// <param name="role"></param>
106        /// <returns>True if user is in the role</returns>
107        /// <exception cref="ConfigurationErrorsException"/>
108        public static bool IsInRole(ApplicationRole role)
109        {
110            string[] roles = GetRoleName(role).Split(';');
111            foreach (string roleName in roles)
112            {
113                if (Thread.CurrentPrincipal.IsInRole(roleName))
114                    return true;
115            }
116            return false;
117        }
118
119        /// <summary>
120        /// Confirms user is in at least 1 of the roles.
121        /// Usage: IsInAnyRole(Role_User | Role_Editor)
122        /// </summary>
123        /// <param name="roles"></param>
124        /// <returns></returns>
125        public static bool IsInAnyRole(ApplicationRole roles)
126        {
127            foreach (string roleName in Enum.GetNames(typeof (ApplicationRole)))
128            {
129                ApplicationRole currentRole = (ApplicationRole) Enum.Parse(typeof (ApplicationRole), roleName);
130                if ((currentRole & roles) == currentRole)
131                {
132                    bool success = IsInRole(currentRole);
133                    if (success)
134                    {
135                        return true;
136                    }
137                }
138            }
139            return false;
140        }
141
142        /// <summary>
143        /// Confirms user is in ALL of the specified roles.
144        /// Usage: IsInAllRoles(Role_Administrator | Role_Editor)
145        /// </summary>
146        /// <param name="roles"></param>
147        /// <returns></returns>
148        public static bool IsInAllRoles(ApplicationRole roles)
149        {
150            foreach (string roleName in Enum.GetNames(typeof (ApplicationRole)))
151            {
152                ApplicationRole currentRole = (ApplicationRole) Enum.Parse(typeof (ApplicationRole), roleName);
153                if ((currentRole & roles) == currentRole)
154                {
155                    if (!IsInRole(currentRole))
156                        return false;
157                }
158            }
159            return true;
160        }
161
162        #endregion
163
164        #region Private helper functions
165
166        private static WindowsIdentity GetCurrentUser()
167        {
168            WindowsIdentity identity = WindowsIdentity.GetCurrent();
169            return identity;
170        }
171
172        private static string GetRoleName(ApplicationRole role)
173        {
174            return GetSetting(Enum.GetName(typeof (ApplicationRole), role));
175        }
176
177        private static string GetUserName()
178        {
179            return GetCurrentUser().Name;
180        }
181
182        private static string GetSetting(string key)
183        {
184            NameValueCollection settings =
185                WebConfigurationManager.GetWebApplicationSection(_ConfigSectionName) as NameValueCollection;
186            //Ensure the section exists 
187            if (settings == null)
188            {
189                throw new ConfigurationErrorsException("The application section (" + _ConfigSectionName +
190                                                       ") does not exist in the configuration file.");
191            }
192            string settingValue = settings[key];
193            //If the value is null then it doesn't exist
194            if (settingValue == null)
195            {
196                throw new ConfigurationErrorsException("The application setting (" + key +
197                                                       ") does not exist in the configuration file.");
198            }
199            return settingValue;
200        }
201
202        #endregion
203    }
204}