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 __SOLANUM_AUTHD_PROVIDER_H__
  22 #define __SOLANUM_AUTHD_PROVIDER_H__
  23
  24 #include "stdinc.h"
  25 #include "authd.h"
  26 #include "rb_dictionary.h"
  27
  28 #define MAX_PROVIDERS 32        /* This should be enough */
  29
  30 typedef enum
  31 {
  32         PROVIDER_STATUS_NOTRUN = 0,
  33         PROVIDER_STATUS_RUNNING,
  34         PROVIDER_STATUS_DONE,
  35 } provider_status_t;
  36
  37 struct auth_client_data
  38 {
  39         struct auth_provider *provider; /* Pointer back */
  40         time_t timeout;                 /* Provider timeout */
  41         void *data;                     /* Provider data */
  42         provider_status_t status;       /* Provider status */
  43 };
  44
  45 struct auth_client
  46 {
  47         uint32_t cid;                           /* Client ID */
  48
  49         int protocol;                           /* IP protocol (TCP/SCTP) */
  50
  51         char l_ip[HOSTIPLEN + 1];               /* Listener IP address */
  52         uint16_t l_port;                        /* Listener port */
  53         struct rb_sockaddr_storage l_addr;      /* Listener address/port */
  54
  55         char c_ip[HOSTIPLEN + 1];               /* Client IP address */
  56         uint16_t c_port;                        /* Client port */
  57         struct rb_sockaddr_storage c_addr;      /* Client address/port */
  58
  59         char hostname[HOSTLEN + 1];             /* Used for DNS lookup */
  60         char username[USERLEN + 1];             /* Used for ident lookup */
  61
  62         bool providers_starting;                /* Providers are still warming up */
  63         bool providers_cancelled;               /* Providers are being cancelled */
  64         unsigned int providers_active;          /* Number of active providers */
  65         unsigned int refcount;                  /* Held references */
  66
  67         struct auth_client_data *data;          /* Provider-specific data */
  68 };
  69
  70 typedef bool (*provider_init_t)(void);
  71 typedef void (*provider_destroy_t)(void);
  72
  73 typedef bool (*provider_start_t)(struct auth_client *);
  74 typedef void (*provider_cancel_t)(struct auth_client *);
  75 typedef void (*uint32_timeout_t)(struct auth_client *);
  76 typedef void (*provider_complete_t)(struct auth_client *, uint32_t);
  77
  78 struct auth_stats_handler
  79 {
  80         const char letter;
  81         authd_stat_handler handler;
  82 };
  83
  84 struct auth_provider
  85 {
  86         rb_dlink_node node;
  87
  88         uint32_t id;                    /* Provider ID */
  89
  90         const char *name;               /* Name of the provider */
  91         char letter;                    /* Letter used on reject, etc. */
  92
  93         provider_init_t init;           /* Initalise the provider */
  94         provider_destroy_t destroy;     /* Terminate the provider */
  95
  96         provider_start_t start;         /* Perform authentication */
  97         provider_cancel_t cancel;       /* Authentication cancelled */
  98         uint32_timeout_t timeout;       /* Timeout callback */
  99         provider_complete_t completed;  /* Callback for when other performers complete (think dependency chains) */
 100
 101         struct auth_stats_handler stats_handler;
 102
 103         struct auth_opts_handler *opt_handlers;
 104 };
 105
 106 extern struct auth_provider rdns_provider;
 107 extern struct auth_provider ident_provider;
 108 extern struct auth_provider dnsbl_provider;
 109 extern struct auth_provider opm_provider;
 110
 111 extern rb_dlink_list auth_providers;
 112 extern rb_dictionary *auth_clients;
 113
 114 void load_provider(struct auth_provider *provider);
 115 void unload_provider(struct auth_provider *provider);
 116
 117 void init_providers(void);
 118 void destroy_providers(void);
 119 void cancel_providers(struct auth_client *auth);
 120
 121 void provider_done(struct auth_client *auth, uint32_t id);
 122 void accept_client(struct auth_client *auth);
 123 void reject_client(struct auth_client *auth, uint32_t id, const char *data, const char *fmt, ...);
 124
 125 void handle_new_connection(int parc, char *parv[]);
 126 void handle_cancel_connection(int parc, char *parv[]);
 127 void auth_client_free(struct auth_client *auth);
 128
 129 static inline void
 130 auth_client_ref(struct auth_client *auth)
 131 {
 132         auth->refcount++;
 133 }
 134
 135 static inline void
 136 auth_client_unref(struct auth_client *auth)
 137 {
 138         auth->refcount--;
 139         if (auth->refcount == 0)
 140                 auth_client_free(auth);
 141 }
 142
 143 /* Get a provider by name */
 144 static inline struct auth_provider *
 145 find_provider(const char *name)
 146 {
 147         rb_dlink_node *ptr;
 148
 149         RB_DLINK_FOREACH(ptr, auth_providers.head)
 150         {
 151                 struct auth_provider *provider = ptr->data;
 152
 153                 if(strcasecmp(provider->name, name) == 0)
 154                         return provider;
 155         }
 156
 157         return NULL;
 158 }
 159
 160 /* Get a provider's id by name */
 161 static inline bool
 162 get_provider_id(const char *name, uint32_t *id)
 163 {
 164         struct auth_provider *provider = find_provider(name);
 165
 166         if(provider != NULL)
 167         {
 168                 *id = provider->id;
 169                 return true;
 170         }
 171         else
 172                 return false;
 173 }
 174
 175 /* Get a provider's raw status */
 176 static inline provider_status_t
 177 get_provider_status(struct auth_client *auth, uint32_t provider)
 178 {
 179         return auth->data[provider].status;
 180 }
 181
 182 /* Check if provider is operating on this auth client */
 183 static inline bool
 184 is_provider_running(struct auth_client *auth, uint32_t provider)
 185 {
 186         return get_provider_status(auth, provider) == PROVIDER_STATUS_RUNNING;
 187 }
 188
 189 /* Check if provider has finished on this client */
 190 static inline bool
 191 is_provider_done(struct auth_client *auth, uint32_t provider)
 192 {
 193         return get_provider_status(auth, provider) == PROVIDER_STATUS_DONE;
 194 }
 195
 196 /* Check if provider doesn't exist or has finished on this client */
 197 static inline bool
 198 run_after_provider(struct auth_client *auth, const char *name)
 199 {
 200         uint32_t id;
 201
 202         if (get_provider_id(name, &id)) {
 203                 return get_provider_status(auth, id) == PROVIDER_STATUS_DONE;
 204         } else {
 205                 return true;
 206         }
 207 }
 208
 209 /* Get provider auth client data */
 210 static inline void *
 211 get_provider_data(struct auth_client *auth, uint32_t id)
 212 {
 213         return auth->data[id].data;
 214 }
 215
 216 /* Set provider auth client data */
 217 static inline void
 218 set_provider_data(struct auth_client *auth, uint32_t id, void *data)
 219 {
 220         auth->data[id].data = data;
 221 }
 222
 223 /* Set timeout relative to current time on provider
 224  * When the timeout lapses, the provider's timeout call will execute */
 225 static inline void
 226 set_provider_timeout_relative(struct auth_client *auth, uint32_t id, time_t timeout)
 227 {
 228         auth->data[id].timeout = timeout + rb_current_time();
 229 }
 230
 231 /* Set timeout value in absolute time (Unix timestamp)
 232  * When the timeout lapses, the provider's timeout call will execute */
 233 static inline void
 234 set_provider_timeout_absolute(struct auth_client *auth, uint32_t id, time_t timeout)
 235 {
 236         auth->data[id].timeout = timeout;
 237 }
 238
 239 /* Get the timeout value for the provider */
 240 static inline time_t
 241 get_provider_timeout(struct auth_client *auth, uint32_t id)
 242 {
 243         return auth->data[id].timeout;
 244 }
 245
 246 #endif /* __SOLANUM_AUTHD_PROVIDER_H__ */