src/src/structs.h

   1 /*************************************************
   2 *     Exim - an Internet mail transport agent    *
   3 *************************************************/
   4
   5 /* Copyright (c) University of Cambridge 1995 - 2012 */
   6 /* See the file NOTICE for conditions of use and distribution. */
   7
   8
   9 /* Definitions of various structures. In addition, those that are visible for
  10 the compilation of local_scan() are defined in local_scan.h. These are
  11
  12   header_line
  13   optionlist
  14   recipient_item
  15
  16 For those declared here, we have to pre-declare some because of mutually
  17 recursive definitions in the auths, routers, and transports blocks. */
  18
  19 struct address_item;
  20 struct auth_info;
  21 struct driver_info;
  22 struct director_info;
  23 struct smtp_inblock;
  24 struct smtp_outblock;
  25 struct transport_info;
  26 struct router_info;
  27
  28 /* Structure for remembering macros for the configuration file */
  29
  30 typedef struct macro_item {
  31   struct  macro_item *next;
  32   BOOL    command_line;
  33   uschar *replacement;
  34   uschar  name[1];
  35 } macro_item;
  36
  37 /* Structure for bit tables for debugging and logging */
  38
  39 typedef struct bit_table {
  40   uschar *name;
  41   unsigned int bit;
  42 } bit_table;
  43
  44 /* Block for holding a uid and gid, possibly unset, and an initgroups flag. */
  45
  46 typedef struct ugid_block {
  47   uid_t   uid;
  48   gid_t   gid;
  49   BOOL    uid_set;
  50   BOOL    gid_set;
  51   BOOL    initgroups;
  52 } ugid_block;
  53
  54 /* Structure for holding information about a host for use mainly by routers,
  55 but also used when checking lists of hosts and when transporting. Looking up
  56 host addresses is done using this structure. */
  57
  58 typedef struct host_item {
  59   struct host_item *next;
  60   uschar *name;                   /* Host name */
  61   uschar *address;                /* IP address in text form */
  62   int     port;                   /* port value in host order (if SRV lookup) */
  63   int     mx;                     /* MX value if found via MX records */
  64   int     sort_key;               /* MX*1000 plus random "fraction" */
  65   int     status;                 /* Usable, unusable, or unknown */
  66   int     why;                    /* Why host is unusable */
  67   int     last_try;               /* Time of last try if known */
  68 } host_item;
  69
  70 /* Chain of rewrite rules, read from the rewrite config, or parsed from the
  71 rewrite_headers field of a transport. */
  72
  73 typedef struct rewrite_rule {
  74   struct rewrite_rule *next;
  75   int     flags;
  76   uschar *key;
  77   uschar *replacement;
  78 } rewrite_rule;
  79
  80 /* This structure is used to pass back configuration data from the smtp
  81 transport to the outside world. It is used during callback processing. If ever
  82 another remote transport were implemented, it could use the same structure. */
  83
  84 typedef struct transport_feedback {
  85   uschar *interface;
  86   uschar *port;
  87   uschar *protocol;
  88   uschar *hosts;
  89   uschar *helo_data;
  90   BOOL   hosts_override;
  91   BOOL   hosts_randomize;
  92   BOOL   gethostbyname;
  93   BOOL   qualify_single;
  94   BOOL   search_parents;
  95 } transport_feedback;
  96
  97 /* Routers, transports, and authenticators have similar data blocks. Each
  98 driver that is compiled into the code is represented by a xxx_info block; the
  99 active drivers are represented by a chain of xxx_instance blocks. To make it
 100 possible to use the same code for reading the configuration files for all
 101 three, the layout of the start of the blocks is kept the same, and represented
 102 by the generic structures driver_info and driver_instance. */
 103
 104 typedef struct driver_instance {
 105   struct driver_instance *next;
 106   uschar *name;                   /* Instance name */
 107   struct driver_info *info;       /* Points to info for this driver */
 108   void   *options_block;          /* Pointer to private options */
 109   uschar *driver_name;            /* All start with this generic option */
 110 } driver_instance;
 111
 112 typedef struct driver_info {
 113   uschar *driver_name;            /* Name of driver */
 114   optionlist *options;            /* Table of private options names */
 115   int    *options_count;          /* -> Number of entries in table */
 116   void   *options_block;          /* Points to default private block */
 117   int     options_len;            /* Length of same in bytes */
 118   void  (*init)(                  /* Initialization entry point */
 119     struct driver_instance *);
 120 } driver_info;
 121
 122
 123 /* Structure for holding information about the configured transports. Some
 124 of the generally accessible options are set from the configuration file; others
 125 are set by transport initialization, since they can only be set for certain
 126 transports. They need to be generally accessible, however, as they are used by
 127 the main transport code. */
 128
 129 typedef struct transport_instance {
 130   struct transport_instance *next;
 131   uschar *name;                   /* Instance name */
 132   struct transport_info *info;    /* Info for this driver */
 133   void *options_block;            /* Pointer to private options */
 134   uschar *driver_name;            /* Must be first */
 135   int   (*setup)(                 /* Setup entry point */
 136     struct transport_instance *,
 137     struct address_item *,
 138     struct transport_feedback *,  /* For passing back config data */
 139     uid_t,                        /* The uid that will be used */
 140     gid_t,                        /* The gid that will be used */
 141     uschar **);                   /* For an error message */
 142                                   /**************************************/
 143   int     batch_max;              /* )                                  */
 144   uschar *batch_id;               /* )                                  */
 145   uschar *home_dir;               /* ) Used only for local transports   */
 146   uschar *current_dir;            /* )                                  */
 147                                   /**************************************/
 148   BOOL    multi_domain;           /* )                                  */
 149   BOOL    overrides_hosts;        /* ) Used only for remote transports  */
 150   int     max_addresses;          /* )                                  */
 151   int     connection_max_messages;/* )                                  */
 152                                   /**************************************/
 153   BOOL    deliver_as_creator;     /* Used only by pipe at present */
 154   BOOL    disable_logging;        /* For very weird requirements */
 155   BOOL    initgroups;             /* Initialize groups when setting uid */
 156   BOOL    uid_set;                /* uid is set */
 157   BOOL    gid_set;                /* gid is set */
 158   uid_t   uid;
 159   gid_t   gid;
 160   uschar *expand_uid;             /* Variable uid */
 161   uschar *expand_gid;             /* Variable gid */
 162   uschar *warn_message;           /* Used only by appendfile at present */
 163   uschar *shadow;                 /* Name of shadow transport */
 164   uschar *shadow_condition;       /* Condition for running it */
 165   uschar *filter_command;         /* For on-the-fly-filtering */
 166   uschar *add_headers;            /* Add these headers */
 167   uschar *remove_headers;         /* Remove these headers */
 168   uschar *return_path;            /* Overriding (rewriting) return path */
 169   uschar *debug_string;           /* Debugging output */
 170   uschar *message_size_limit;     /* Biggest message this transport handles */
 171   uschar *headers_rewrite;        /* Rules for rewriting headers */
 172   rewrite_rule *rewrite_rules;    /* Parsed rewriting rules */
 173   int     rewrite_existflags;     /* Bits showing which headers are rewritten */
 174   int     filter_timeout;         /* For transport filter timing */
 175   BOOL    body_only;              /* Deliver only the body */
 176   BOOL    delivery_date_add;      /* Add Delivery-Date header */
 177   BOOL    envelope_to_add;        /* Add Envelope-To header */
 178   BOOL    headers_only;           /* Deliver only the headers */
 179   BOOL    rcpt_include_affixes;   /* TRUE to retain affixes in RCPT commands */
 180   BOOL    return_path_add;        /* Add Return-Path header */
 181   BOOL    return_output;          /* TRUE if output should always be returned */
 182   BOOL    return_fail_output;     /* ditto, but only on failure */
 183   BOOL    log_output;             /* Similarly for logging */
 184   BOOL    log_fail_output;
 185   BOOL    log_defer_output;
 186   BOOL    retry_use_local_part;   /* Defaults true for local, false for remote */
 187 } transport_instance;
 188
 189
 190 /* Structure for holding information about a type of transport. The first six
 191 fields must match driver_info above. */
 192
 193 typedef struct transport_info {
 194   uschar *driver_name;            /* Driver name */
 195   optionlist *options;            /* Table of private options names */
 196   int    *options_count;          /* -> Number of entries in table */
 197   void   *options_block;          /* Points to default private block */
 198   int     options_len;            /* Length of same in bytes */
 199   void (*init)(                   /* Initialization function */
 200     struct transport_instance *);
 201 /****/
 202   BOOL (*code)(                   /* Main entry point */
 203     transport_instance *,
 204     struct address_item *);
 205   void (*tidyup)(                 /* Tidyup function */
 206     struct transport_instance *);
 207   void  (*closedown)(             /* For closing down a passed channel */
 208     struct transport_instance *);
 209   BOOL    local;                  /* TRUE for local transports */
 210 } transport_info;
 211
 212
 213
 214 /* Structure for holding information about the configured routers. */
 215
 216 typedef struct router_instance {
 217   struct router_instance *next;
 218   uschar *name;
 219   struct router_info *info;
 220   void   *options_block;          /* Pointer to private options */
 221   uschar *driver_name;            /* Must be first */
 222
 223   uschar *address_data;           /* Arbitrary data */
 224 #ifdef EXPERIMENTAL_BRIGHTMAIL
 225   uschar *bmi_rule;               /* Brightmail AntiSpam rule checking */
 226 #endif
 227   uschar *cannot_route_message;   /* Used when routing fails */
 228   uschar *condition;              /* General condition */
 229   uschar *current_directory;      /* For use during delivery */
 230   uschar *debug_string;           /* Debugging output */
 231   uschar *domains;                /* Specific domains */
 232   uschar *errors_to;              /* Errors address */
 233   uschar *expand_gid;             /* Expanded gid string */
 234   uschar *expand_uid;             /* Expanded uid string */
 235   uschar *expand_more;            /* Expanded more string */
 236   uschar *expand_unseen;          /* Expanded unseen string */
 237   uschar *extra_headers;          /* Additional headers */
 238   uschar *fallback_hosts;         /* For remote transports (text list) */
 239   uschar *home_directory;         /* For use during delivery */
 240   uschar *ignore_target_hosts;    /* Target hosts to ignore */
 241   uschar *local_parts;            /* Specific local parts */
 242   uschar *pass_router_name;       /* Router for passed address */
 243   uschar *prefix;                 /* Address prefix */
 244   uschar *redirect_router_name;   /* Router for generated address */
 245   uschar *remove_headers;         /* Removed headers */
 246   uschar *require_files;          /* File checks before router is run */
 247   uschar *router_home_directory;  /* For use while routing */
 248   uschar *self;                   /* Text option for handling self reference */
 249   uschar *senders;                /* Specific senders */
 250   uschar *suffix;                 /* Address suffix */
 251   uschar *translate_ip_address;   /* IP address translation fudgery */
 252   uschar *transport_name;         /* Transport name */
 253
 254   BOOL    address_test;           /* Use this router when testing addresses */
 255 #ifdef EXPERIMENTAL_BRIGHTMAIL
 256   BOOL    bmi_deliver_alternate;  /* TRUE => BMI said that message should be delivered to alternate location */
 257   BOOL    bmi_deliver_default;    /* TRUE => BMI said that message should be delivered to default location */
 258   BOOL    bmi_dont_deliver;       /* TRUE => BMI said that message should not be delivered at all */
 259 #endif
 260   BOOL    expn;                   /* Use this router when processing EXPN */
 261   BOOL    caseful_local_part;     /* TRUE => don't lowercase */
 262   BOOL    check_local_user;       /* TRUE => check local user */
 263   BOOL    disable_logging;        /* For very weird requirements */
 264   BOOL    fail_verify_recipient;  /* Fail verify if recipient match this router */
 265   BOOL    fail_verify_sender;     /* Fail verify if sender match this router */
 266   BOOL    gid_set;                /* Flag to indicate gid is set */
 267   BOOL    initgroups;             /* TRUE if initgroups is required */
 268   BOOL    log_as_local;           /* TRUE logs as a local delivery */
 269   BOOL    more;                   /* If FALSE, do no more if this one fails */
 270   BOOL    pass_on_timeout;        /* Treat timeout DEFERs as fails */
 271   BOOL    prefix_optional;        /* Just what it says */
 272   BOOL    repeat_use;             /* If FALSE, skip if ancestor used it */
 273   BOOL    retry_use_local_part;   /* Just what it says */
 274   BOOL    same_domain_copy_routing; /* TRUE => copy routing for same domain */
 275   BOOL    self_rewrite;           /* TRUE to rewrite headers if making local */
 276   BOOL    suffix_optional;        /* As it says */
 277   BOOL    verify_only;            /* Skip this router if not verifying */
 278   BOOL    verify_recipient;       /* Use this router when verifying a recipient*/
 279   BOOL    verify_sender;          /* Use this router when verifying a sender */
 280   BOOL    uid_set;                /* Flag to indicate uid is set */
 281   BOOL    unseen;                 /* If TRUE carry on, even after success */
 282
 283   int     self_code;              /* Encoded version of "self" */
 284   uid_t   uid;                    /* Fixed uid value */
 285   gid_t   gid;                    /* Fixed gid value */
 286
 287   host_item *fallback_hostlist;   /* For remote transport (block chain) */
 288   transport_instance *transport;  /* Transport block (when found) */
 289   struct router_instance *pass_router; /* Actual router for passed address */
 290   struct router_instance *redirect_router; /* Actual router for generated address */
 291 } router_instance;
 292
 293
 294 /* Structure for holding information about a type of router. The first six
 295 fields must match driver_info above. */
 296
 297 typedef struct router_info {
 298   uschar *driver_name;
 299   optionlist *options;            /* Table of private options names */
 300   int    *options_count;          /* -> Number of entries in table */
 301   void   *options_block;          /* Points to default private block */
 302   int     options_len;            /* Length of same in bytes */
 303   void (*init)(                   /* Initialization function */
 304     struct router_instance *);
 305 /****/
 306   int (*code)(                    /* Main entry point */
 307     router_instance *,
 308     struct address_item *,
 309     struct passwd *,
 310     int,
 311     struct address_item **,
 312     struct address_item **,
 313     struct address_item **,
 314     struct address_item **);
 315   void (*tidyup)(                 /* Tidyup function */
 316     struct router_instance *);
 317   int     ri_flags;               /* Descriptive flags */
 318 } router_info;
 319
 320
 321 /* Structure for holding information about a lookup type. */
 322
 323 #include "lookupapi.h"
 324
 325
 326 /* Structure for holding information about the configured authentication
 327 mechanisms */
 328
 329 typedef struct auth_instance {
 330   struct auth_instance *next;
 331   uschar *name;                   /* Exim instance name */
 332   struct auth_info *info;         /* Pointer to driver info block */
 333   void   *options_block;          /* Pointer to private options */
 334   uschar *driver_name;            /* Must be first */
 335   uschar *advertise_condition;    /* Are we going to advertise this?*/
 336   uschar *client_condition;       /* Should the client try this? */
 337   uschar *public_name;            /* Advertised name */
 338   uschar *set_id;                 /* String to set when server as authenticated id */
 339   uschar *set_client_id;          /* String to set when client as client_authenticated id */
 340   uschar *mail_auth_condition;    /* Condition for AUTH on MAIL command */
 341   uschar *server_debug_string;    /* Debugging output */
 342   uschar *server_condition;       /* Authorization condition */
 343   BOOL    client;                 /* TRUE if client option(s) set */
 344   BOOL    server;                 /* TRUE if server options(s) set */
 345   BOOL    advertised;             /* Set TRUE when advertised */
 346 } auth_instance;
 347
 348
 349 /* Structure for holding information about an authentication mechanism. The
 350 first six fields must match driver_info above. */
 351
 352 typedef struct auth_info {
 353   uschar *driver_name;            /* e.g. "condition" */
 354   optionlist *options;            /* Table of private options names */
 355   int    *options_count;          /* -> Number of entries in table */
 356   void   *options_block;          /* Points to default private block */
 357   int     options_len;            /* Length of same in bytes */
 358   void (*init)(                   /* initialization function */
 359     struct auth_instance *);
 360 /****/
 361   int (*servercode)(              /* server function */
 362     auth_instance *,              /* the instance data */
 363     uschar *);                    /* rest of AUTH command */
 364   int (*clientcode)(              /* client function */
 365     struct auth_instance *,
 366     struct smtp_inblock *,        /* socket and input buffer */
 367     struct smtp_outblock *,       /* socket and output buffer */
 368     int,                          /* command timeout */
 369     uschar *,                     /* buffer for reading response */
 370     int);                         /* sizeof buffer */
 371   void (*version_report)(         /* diagnostic version reporting */
 372     FILE *);                      /* I/O stream to print to */
 373 } auth_info;
 374
 375
 376 /* Structure for holding a single IP address and port; used for the chain of
 377 addresses and ports for the local host. Make the char string large enough to
 378 hold an IPv6 address. */
 379
 380 typedef struct ip_address_item {
 381   struct ip_address_item *next;
 382   int    port;
 383   BOOL   v6_include_v4;            /* Used in the daemon */
 384   uschar address[46];
 385 } ip_address_item;
 386
 387 /* Structure for chaining together arbitrary strings. */
 388
 389 typedef struct string_item {
 390   struct string_item *next;
 391   uschar *text;
 392 } string_item;
 393
 394 /* Information about a soft delivery failure, for use when calculating
 395 retry information. It's separate from the address block, because there
 396 can be a chain of them for SMTP deliveries where multiple IP addresses
 397 can be tried. */
 398
 399 typedef struct retry_item {
 400   struct retry_item *next;        /* for chaining */
 401   uschar *key;                    /* string identifying host/address/message */
 402   int     basic_errno;            /* error code for this destination */
 403   int     more_errno;             /* additional error information */
 404   uschar *message;                /* local error message */
 405   int     flags;                  /* see below */
 406 } retry_item;
 407
 408 /* Retry data flags */
 409
 410 #define rf_delete   0x0001        /* retry info is to be deleted */
 411 #define rf_host     0x0002        /* retry info is for a remote host */
 412 #define rf_message  0x0004        /* retry info is for a host+message */
 413
 414 /* Information about a constructed message that is to be sent using the
 415 autoreply transport. This is pointed to from the address block. */
 416
 417 typedef struct reply_item {
 418   uschar *from;                   /* ) */
 419   uschar *reply_to;               /* ) */
 420   uschar *to;                     /* ) */
 421   uschar *cc;                     /* ) specific header fields */
 422   uschar *bcc;                    /* ) */
 423   uschar *subject;                /* ) */
 424   uschar *headers;                /* misc other headers, concatenated */
 425   uschar *text;                   /* text string body */
 426   uschar *file;                   /* file body */
 427   BOOL    file_expand;            /* expand the body */
 428   int     expand_forbid;          /* expansion lockout flags */
 429   uschar *logfile;                /* file to keep a log in */
 430   uschar *oncelog;                /* file to keep records in for once only */
 431   time_t  once_repeat;            /* time to repeat "once only" */
 432   BOOL    return_message;         /* send back the original message */
 433 } reply_item;
 434
 435
 436 /* The address_item structure contains many fields which are used at various
 437 times while delivering a message. Some are used only for remote deliveries;
 438 some only for local. A particular set of fields is copied whenever a child
 439 address is created. For convenience, we keep those fields in a separate
 440 sub-structure so they can be copied in one go. This also means I won't forget
 441 to edit the various copying places when new to-be-copied fields are added. */
 442
 443 typedef struct address_item_propagated {
 444   uschar *address_data;           /* arbitrary data to keep with the address */
 445   uschar *domain_data;            /* from "domains" lookup */
 446   uschar *localpart_data;         /* from "local_parts" lookup */
 447   uschar *errors_address;         /* where to send errors (NULL => sender) */
 448   header_line *extra_headers;     /* additional headers */
 449   uschar *remove_headers;         /* list of those to remove */
 450
 451   #ifdef EXPERIMENTAL_SRS
 452   uschar *srs_sender;             /* Change return path when delivering */
 453   #endif
 454 } address_item_propagated;
 455
 456 /* Bits for the flags field below */
 457
 458 #define af_allow_file          0x00000001 /* allow file in generated address */
 459 #define af_allow_pipe          0x00000002 /* allow pipe in generated address */
 460 #define af_allow_reply         0x00000004 /* allow autoreply in generated address */
 461 #define af_dr_retry_exists     0x00000008 /* router retry record exists */
 462 #define af_expand_pipe         0x00000010 /* expand pipe arguments */
 463 #define af_file                0x00000020 /* file delivery; always with pfr */
 464 #define af_gid_set             0x00000040 /* gid field is set */
 465 #define af_home_expanded       0x00000080 /* home_dir is already expanded */
 466 #define af_ignore_error        0x00000100 /* ignore delivery error */
 467 #define af_initgroups          0x00000200 /* use initgroups() for local transporting */
 468 #define af_local_host_removed  0x00000400 /* local host was backup */
 469 #define af_lt_retry_exists     0x00000800 /* local transport retry exists */
 470 #define af_pfr                 0x00001000 /* pipe or file or reply delivery */
 471 #define af_retry_skipped       0x00002000 /* true if retry caused some skipping */
 472 #define af_retry_timedout      0x00004000 /* true if retry timed out */
 473 #define af_uid_set             0x00008000 /* uid field is set */
 474 #define af_hide_child          0x00010000 /* hide child in bounce/defer msgs */
 475 #define af_sverify_told        0x00020000 /* sender verify failure notified */
 476 #define af_verify_pmfail       0x00040000 /* verify failure was postmaster callout */
 477 #define af_verify_nsfail       0x00080000 /* verify failure was null sender callout */
 478 #define af_homonym             0x00100000 /* an ancestor has same address */
 479 #define af_verify_routed       0x00200000 /* for cached sender verify: routed OK */
 480 #define af_verify_callout      0x00400000 /* for cached sender verify: callout was specified */
 481 #define af_include_affixes     0x00800000 /* delivered with affixes in RCPT */
 482 #define af_cert_verified       0x01000000 /* delivered with verified TLS cert */
 483 #define af_pass_message        0x02000000 /* pass message in bounces */
 484 #define af_bad_reply           0x04000000 /* filter could not generate autoreply */
 485
 486 /* These flags must be propagated when a child is created */
 487
 488 #define af_propagate           (af_ignore_error)
 489
 490 /* The main address structure. Note that fields that are to be copied to
 491 generated addresses should be put in the address_item_propagated structure (see
 492 above) rather than directly into the address_item structure. */
 493
 494 typedef struct address_item {
 495   struct address_item *next;      /* for chaining addresses */
 496   struct address_item *parent;    /* parent address */
 497   struct address_item *first;     /* points to first after group delivery */
 498   struct address_item *dupof;     /* points to address this is a duplicate of */
 499
 500   router_instance *start_router;  /* generated address starts here */
 501   router_instance *router;        /* the router that routed */
 502   transport_instance *transport;  /* the transport to use */
 503
 504   host_item *host_list;           /* host data for the transport */
 505   host_item *host_used;           /* host that took delivery or failed hard */
 506   host_item *fallback_hosts;      /* to try if delivery defers */
 507
 508   reply_item *reply;              /* data for autoreply */
 509   retry_item *retries;            /* chain of retry information */
 510
 511   uschar *address;                /* address being delivered or routed */
 512   uschar *unique;                 /* used for disambiguating */
 513   uschar *cc_local_part;          /* caseful local part */
 514   uschar *lc_local_part;          /* lowercased local part */
 515   uschar *local_part;             /* points to cc or lc version */
 516   uschar *prefix;                 /* stripped prefix of local part */
 517   uschar *suffix;                 /* stripped suffix of local part */
 518   uschar *domain;                 /* working domain (lower cased) */
 519
 520   uschar *address_retry_key;      /* retry key including full address */
 521   uschar *domain_retry_key;       /* retry key for domain only */
 522
 523   uschar *current_dir;            /* current directory for transporting */
 524   uschar *home_dir;               /* home directory for transporting */
 525   uschar *message;                /* error message */
 526   uschar *user_message;           /* error message that can be sent over SMTP
 527                                      or quoted in bounce message */
 528   uschar *onetime_parent;         /* saved original parent for onetime */
 529   uschar **pipe_expandn;          /* numeric expansions for pipe from filter */
 530   uschar *return_filename;        /* name of return file */
 531   uschar *self_hostname;          /* after self=pass */
 532   uschar *shadow_message;         /* info about shadow transporting */
 533
 534   #ifdef SUPPORT_TLS
 535   uschar *cipher;                 /* Cipher used for transport */
 536   uschar *peerdn;                 /* DN of server's certificate */
 537   #endif
 538
 539   uschar *authenticator;          /* auth driver name used by transport */
 540   uschar *auth_id;                /* auth "login" name used by transport */
 541   uschar *auth_sndr;              /* AUTH arg to SMTP MAIL, used by transport */
 542
 543   uid_t   uid;                    /* uid for transporting */
 544   gid_t   gid;                    /* gid for transporting */
 545
 546   unsigned int flags;             /* a row of bits, defined above */
 547   unsigned int domain_cache[(MAX_NAMED_LIST * 2)/32];
 548   unsigned int localpart_cache[(MAX_NAMED_LIST * 2)/32];
 549   int     mode;                   /* mode for local transporting to a file */
 550   int     more_errno;             /* additional error information */
 551                                   /* (may need to hold a timestamp) */
 552
 553   short int basic_errno;          /* status after failure */
 554   short int child_count;          /* number of child addresses */
 555   short int return_file;          /* fileno of return data file */
 556   short int special_action;       /* ( used when when deferred or failed */
 557                                   /* (  also  */
 558                                   /* ( contains = or - when successful SMTP delivered */
 559                                   /* (  also  */
 560                                   /* ( contains verify rc in sender verify cache */
 561   short int transport_return;     /* result of delivery attempt */
 562   address_item_propagated p;      /* fields that are propagated to children */
 563 } address_item;
 564
 565 /* The table of header names consists of items of this type */
 566
 567 typedef struct {
 568   uschar *name;
 569   int     len;
 570   BOOL    allow_resent;
 571   int     htype;
 572 } header_name;
 573
 574 /* Chain of information about errors (e.g. bad addresses) */
 575
 576 typedef struct error_block {
 577   struct error_block *next;
 578   uschar *text1;
 579   uschar *text2;
 580 } error_block;
 581
 582 /* Chain of file names when processing the queue */
 583
 584 typedef struct queue_filename {
 585   struct queue_filename *next;
 586   uschar dir_uschar;
 587   uschar text[1];
 588 } queue_filename;
 589
 590 /* Chain of items of retry information, read from the retry config. */
 591
 592 typedef struct retry_rule {
 593   struct retry_rule *next;
 594   int    rule;
 595   int    timeout;
 596   int    p1;
 597   int    p2;
 598 } retry_rule;
 599
 600 typedef struct retry_config {
 601   struct retry_config *next;
 602   uschar *pattern;
 603   int     basic_errno;
 604   int     more_errno;
 605   uschar *senders;
 606   retry_rule *rules;
 607 } retry_config;
 608
 609 /* Structure for each node in a tree, of which there are various kinds */
 610
 611 typedef struct tree_node {
 612   struct tree_node *left;         /* pointer to left child */
 613   struct tree_node *right;        /* pointer to right child */
 614   union
 615     {
 616     void  *ptr;                   /* pointer to data */
 617     int val;                      /* or integer data */
 618     } data;
 619   uschar  balance;                /* balancing factor */
 620   uschar  name[1];                /* node name - variable length */
 621 } tree_node;
 622
 623 /* Structure for holding the handle and the cached last lookup for searches.
 624 This block is pointed to by the tree entry for the file. The file can get
 625 closed if too many are opened at once. There is a LRU chain for deciding which
 626 to close. */
 627
 628 typedef struct search_cache {
 629   void   *handle;                 /* lookup handle, or NULL if closed */
 630   int search_type;                /* search type */
 631   tree_node *up;                  /* LRU up pointer */
 632   tree_node *down;                /* LRU down pointer */
 633   tree_node *item_cache;          /* tree of cached results */
 634 } search_cache;
 635
 636 /* Structure for holding a partially decoded DNS record; the name has been
 637 uncompressed, but the data pointer is into the raw data. */
 638
 639 typedef struct {
 640   uschar  name[DNS_MAXNAME];      /* domain name */
 641   int     type;                   /* record type */
 642   int     size;                   /* size of data */
 643   uschar *data;                   /* pointer to data */
 644 } dns_record;
 645
 646 /* Structure for holding the result of a DNS query. */
 647
 648 typedef struct {
 649   int     answerlen;              /* length of the answer */
 650   uschar  answer[MAXPACKET];      /* the answer itself */
 651 } dns_answer;
 652
 653 /* Structure for holding the intermediate data while scanning a DNS answer
 654 block. */
 655
 656 typedef struct {
 657   int     rrcount;                /* count of RRs in the answer */
 658   uschar *aptr;                   /* pointer in the answer while scanning */
 659   dns_record srr;                 /* data from current record in scan */
 660 } dns_scan;
 661
 662 /* Structure for holding a chain of IP addresses that are extracted from
 663 an A, AAAA, or A6 record. For the first two, there is only ever one address,
 664 but the chaining feature of A6 allows for several addresses to be realized from
 665 a single initial A6 record. The structure defines the address field of length
 666 1. In use, a suitable sized block is obtained to hold the complete textual
 667 address. */
 668
 669 typedef struct dns_address {
 670   struct dns_address *next;
 671   uschar  address[1];
 672 } dns_address;
 673
 674 /* Structure used for holding intermediate data during MD5 computations. */
 675
 676 typedef struct md5 {
 677   unsigned int length;
 678   unsigned int abcd[4];
 679   }
 680 md5;
 681
 682 /* Structure used for holding intermediate data during SHA-1 computations. */
 683
 684 typedef struct sha1 {
 685   unsigned int H[5];
 686   unsigned int length;
 687   }
 688 sha1;
 689
 690 /* Structure used to hold incoming packets of SMTP responses for a specific
 691 socket. The packets which may contain multiple lines (and in some cases,
 692 multiple responses). */
 693
 694 typedef struct smtp_inblock {
 695   int     sock;                   /* the socket */
 696   int     buffersize;             /* the size of the buffer */
 697   uschar *ptr;                    /* current position in the buffer */
 698   uschar *ptrend;                 /* end of data in the buffer */
 699   uschar *buffer;                 /* the buffer itself */
 700 } smtp_inblock;
 701
 702 /* Structure used to hold buffered outgoing packets of SMTP commands for a
 703 specific socket. The packets which may contain multiple lines when pipelining
 704 is in use. */
 705
 706 typedef struct smtp_outblock {
 707   int     sock;                   /* the socket */
 708   int     cmd_count;              /* count of buffered commands */
 709   int     buffersize;             /* the size of the buffer */
 710   BOOL    authenticating;         /* TRUE when authenticating */
 711   uschar *ptr;                    /* current position in the buffer */
 712   uschar *buffer;                 /* the buffer itself */
 713 } smtp_outblock;
 714
 715 /* Structure to hold information about the source of redirection information */
 716
 717 typedef struct redirect_block {
 718   uschar *string;                 /* file name or string */
 719   uid_t  *owners;                 /* allowed file owners */
 720   gid_t  *owngroups;              /* allowed file groups */
 721   struct passwd *pw;              /* possible owner if not NULL */
 722   int     modemask;               /* forbidden bits */
 723   BOOL    isfile;                 /* TRUE if string is a file name */
 724   BOOL    check_owner;            /* TRUE, FALSE, or TRUE_UNSET */
 725   BOOL    check_group;            /* TRUE, FALSE, or TRUE_UNSET */
 726 } redirect_block;
 727
 728 /* Structure for passing arguments to check_host() */
 729
 730 typedef struct check_host_block {
 731   uschar *host_name;
 732   uschar *host_address;
 733   uschar *host_ipv4;
 734   BOOL   negative;
 735 } check_host_block;
 736
 737 /* Structure for remembering lookup data when caching the result of
 738 a lookup in a named list. */
 739
 740 typedef struct namedlist_cacheblock {
 741   struct namedlist_cacheblock *next;
 742   uschar *key;
 743   uschar *data;
 744 } namedlist_cacheblock;
 745
 746 /* Structure for holding data for an entry in a named list */
 747
 748 typedef struct namedlist_block {
 749   uschar *string;                    /* the list string */
 750   namedlist_cacheblock *cache_data;  /* cached domain_data or localpart_data */
 751   int number;                        /* the number of the list for caching */
 752 } namedlist_block;
 753
 754 /* Structures for Access Control Lists */
 755
 756 typedef struct acl_condition_block {
 757   struct acl_condition_block *next;
 758   uschar *arg;
 759   int type;
 760   union {
 761     BOOL negated;
 762     uschar *varname;
 763   } u;
 764 } acl_condition_block;
 765
 766 typedef struct acl_block {
 767   struct acl_block *next;
 768   acl_condition_block *condition;
 769   int verb;
 770 } acl_block;
 771
 772 /* End of structs.h */