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 #include "rb_dictionary.h"
  26
  27 #define MAX_PROVIDERS 32        /* This should be enough */
  28
  29 /* Registered providers */
  30 typedef enum
  31 {
  32         PROVIDER_RDNS,
  33         PROVIDER_IDENT,
  34         PROVIDER_BLACKLIST,
  35 } provider_t;
  36
  37 struct auth_client
  38 {
  39         uint16_t cid;                           /* Client ID */
  40
  41         char l_ip[HOSTIPLEN + 1];               /* Listener IP address */
  42         uint16_t l_port;                        /* Listener port */
  43
  44         char c_ip[HOSTIPLEN + 1];               /* Client IP address */
  45         uint16_t c_port;                        /* Client port */
  46
  47         char hostname[HOSTLEN + 1];             /* Used for DNS lookup */
  48         char username[USERLEN + 1];             /* Used for ident lookup */
  49
  50         uint32_t providers;                     /* Providers at work,
  51                                                  * none left when set to 0 */
  52
  53         void *data[MAX_PROVIDERS];              /* Provider-specific data slots */
  54 };
  55
  56 typedef bool (*provider_init_t)(void);
  57 typedef bool (*provider_perform_t)(struct auth_client *);
  58 typedef void (*provider_complete_t)(struct auth_client *, provider_t provider);
  59 typedef void (*provider_cancel_t)(struct auth_client *);
  60 typedef void (*provider_destroy_t)(void);
  61
  62 struct auth_provider
  63 {
  64         rb_dlink_node node;
  65
  66         provider_t id;
  67
  68         provider_init_t init;           /* Initalise the provider */
  69         provider_destroy_t destroy;     /* Terminate the provider */
  70
  71         provider_perform_t start;       /* Perform authentication */
  72         provider_cancel_t cancel;       /* Authentication cancelled */
  73         provider_complete_t completed;  /* Callback for when other performers complete (think dependency chains) */
  74 };
  75
  76 extern rb_dlink_list auth_providers;
  77 extern struct Dictionary *auth_clients;
  78
  79 extern struct auth_provider rdns_provider;
  80 extern struct auth_provider ident_provider;
  81
  82 void load_provider(struct auth_provider *provider);
  83 void unload_provider(struct auth_provider *provider);
  84
  85 void init_providers(void);
  86 void destroy_providers(void);
  87 void cancel_providers(struct auth_client *auth);
  88
  89 void provider_done(struct auth_client *auth, provider_t id);
  90 void accept_client(struct auth_client *auth, provider_t id);
  91 void reject_client(struct auth_client *auth, provider_t id, const char *reason);
  92
  93 void notice_client(struct auth_client *auth, const char *notice);
  94
  95 void handle_new_connection(int parc, char *parv[]);
  96
  97 /* Provider is operating on this auth_client (set this if you have async work to do) */
  98 static inline void set_provider(struct auth_client *auth, provider_t provider)
  99 {
 100         auth->providers |= (1 << provider);
 101 }
 102
 103 /* Provider is no longer operating on this auth client (you should use provider_done) */
 104 static inline void unset_provider(struct auth_client *auth, provider_t provider)
 105 {
 106         auth->providers &= ~(1 << provider);
 107 }
 108
 109 /* Check if provider is operating on this auth client */
 110 static inline bool is_provider(struct auth_client *auth, provider_t provider)
 111 {
 112         return auth->providers & (1 << provider);
 113 }
 114
 115 #endif /* __CHARYBDIS_AUTHD_PROVIDER_H__ */