authd/provider.h

   1 /* authd/provider.h - authentication provider framework
   2  * Copyright (c) 2016 Elizabeth Myers <elizabeth@interlinked.me>
   3  *
   4  * Permission to use, copy, modify, and/or distribute this software for any
   5  * purpose with or without fee is hereby granted, provided that the above
   6  * copyright notice and this permission notice is present in all copies.
   7  *
   8  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
   9  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  10  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  11  * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
  12  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  13  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  14  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  15  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  16  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  17  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  18  * POSSIBILITY OF SUCH DAMAGE.
  19  */
  20
  21 #ifndef __CHARYBDIS_AUTHD_PROVIDER_H__
  22 #define __CHARYBDIS_AUTHD_PROVIDER_H__
  23
  24 #include "stdinc.h"
  25
  26 /* Arbitrary limit */
  27 #define MAX_CLIENTS 4096
  28
  29 /* Registered providers */
  30 typedef enum
  31 {
  32         PROVIDER_NULL = 0x0, /* Dummy value */
  33         PROVIDER_RDNS = 0x1,
  34         PROVIDER_IDENT = 0x2,
  35         PROVIDER_BLACKLIST = 0x4,
  36 } provider_t;
  37
  38 struct auth_client
  39 {
  40         uint16_t cid;                           /* Client ID */
  41
  42         struct rb_sockaddr_storage l_addr;      /* Listener IP address */
  43         struct rb_sockaddr_storage c_addr;      /* Client IP address */
  44
  45         char hostname[HOSTLEN + 1];             /* Used for DNS lookup */
  46         char username[USERLEN + 1];             /* Used for ident lookup */
  47
  48         unsigned int providers;                 /* Providers at work,
  49                                                  * none left when set to 0 */
  50 };
  51
  52 typedef bool (*provider_init_t)(void);
  53 typedef bool (*provider_perform_t)(struct auth_client *);
  54 typedef void (*provider_complete_t)(struct auth_client *, provider_t provider);
  55 typedef void (*provider_cancel_t)(struct auth_client *);
  56 typedef void (*provider_destroy_t)(void);
  57
  58 struct auth_provider
  59 {
  60         rb_dlink_node node;
  61
  62         provider_t id;
  63
  64         provider_init_t init;           /* Initalise the provider */
  65         provider_destroy_t destroy;     /* Terminate the provider */
  66
  67         provider_perform_t start;       /* Perform authentication */
  68         provider_cancel_t cancel;       /* Authentication cancelled */
  69         provider_complete_t completed;  /* Callback for when other performers complete (think dependency chains) */
  70 };
  71
  72 extern rb_dlink_list auth_providers;
  73 extern struct auth_provider rdns_provider;
  74 extern struct auth_provider ident_provider;
  75
  76 extern struct auth_client auth_clients[MAX_CLIENTS];
  77
  78 void load_provider(struct auth_provider *provider);
  79 void unload_provider(struct auth_provider *provider);
  80
  81 void init_providers(void);
  82 void destroy_providers(void);
  83 void cancel_providers(struct auth_client *auth);
  84
  85 void provider_done(struct auth_client *auth, provider_t provider);
  86 void reject_client(struct auth_client *auth, provider_t provider, const char *reason);
  87 void accept_client(struct auth_client *auth, provider_t provider);
  88
  89 void notice_client(struct auth_client *auth, const char *notice);
  90
  91 void handle_new_connection(int parc, char *parv[]);
  92
  93 /* Provider is operating on this auth_client (set this if you have async work to do) */
  94 static inline void set_provider(struct auth_client *auth, provider_t provider)
  95 {
  96         auth->providers |= provider;
  97 }
  98
  99 /* Provider is no longer operating on this auth client (you should use provider_done) */
 100 static inline void unset_provider(struct auth_client *auth, provider_t provider)
 101 {
 102         auth->providers &= ~provider;
 103 }
 104
 105 /* Check if provider is operating on this auth client */
 106 static inline bool is_provider(struct auth_client *auth, provider_t provider)
 107 {
 108         return auth->providers & provider;
 109 }
 110
 111 #endif /* __CHARYBDIS_AUTHD_PROVIDER_H__ */