src/structs.h

   1 /*************************************************
   2 *     Exim - an Internet mail transport agent    *
   3 *************************************************/
   4
   5 /* Copyright (c) University of Cambridge 1995 - 2014 */
   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 enum {DS_UNK=-1, DS_NO, DS_YES} dnssec_status_t;
  59
  60 typedef struct host_item {
  61   struct host_item *next;
  62   uschar *name;                   /* Host name */
  63   uschar *address;                /* IP address in text form */
  64   int     port;                   /* port value in host order (if SRV lookup) */
  65   int     mx;                     /* MX value if found via MX records */
  66   int     sort_key;               /* MX*1000 plus random "fraction" */
  67   int     status;                 /* Usable, unusable, or unknown */
  68   int     why;                    /* Why host is unusable */
  69   int     last_try;               /* Time of last try if known */
  70   dnssec_status_t dnssec;
  71 } host_item;
  72
  73 /* Chain of rewrite rules, read from the rewrite config, or parsed from the
  74 rewrite_headers field of a transport. */
  75
  76 typedef struct rewrite_rule {
  77   struct rewrite_rule *next;
  78   int     flags;
  79   uschar *key;
  80   uschar *replacement;
  81 } rewrite_rule;
  82
  83 /* This structure is used to pass back configuration data from the smtp
  84 transport to the outside world. It is used during callback processing. If ever
  85 another remote transport were implemented, it could use the same structure. */
  86
  87 typedef struct transport_feedback {
  88   uschar *interface;
  89   uschar *port;
  90   uschar *protocol;
  91   uschar *hosts;
  92   uschar *helo_data;
  93   BOOL   hosts_override;
  94   BOOL   hosts_randomize;
  95   BOOL   gethostbyname;
  96   BOOL   qualify_single;
  97   BOOL   search_parents;
  98 } transport_feedback;
  99
 100 /* Routers, transports, and authenticators have similar data blocks. Each
 101 driver that is compiled into the code is represented by a xxx_info block; the
 102 active drivers are represented by a chain of xxx_instance blocks. To make it
 103 possible to use the same code for reading the configuration files for all
 104 three, the layout of the start of the blocks is kept the same, and represented
 105 by the generic structures driver_info and driver_instance. */
 106
 107 typedef struct driver_instance {
 108   struct driver_instance *next;
 109   uschar *name;                   /* Instance name */
 110   struct driver_info *info;       /* Points to info for this driver */
 111   void   *options_block;          /* Pointer to private options */
 112   uschar *driver_name;            /* All start with this generic option */
 113 } driver_instance;
 114
 115 typedef struct driver_info {
 116   uschar *driver_name;            /* Name of driver */
 117   optionlist *options;            /* Table of private options names */
 118   int    *options_count;          /* -> Number of entries in table */
 119   void   *options_block;          /* Points to default private block */
 120   int     options_len;            /* Length of same in bytes */
 121   void  (*init)(                  /* Initialization entry point */
 122     struct driver_instance *);
 123 } driver_info;
 124
 125
 126 /* Structure for holding information about the configured transports. Some
 127 of the generally accessible options are set from the configuration file; others
 128 are set by transport initialization, since they can only be set for certain
 129 transports. They need to be generally accessible, however, as they are used by
 130 the main transport code. */
 131
 132 typedef struct transport_instance {
 133   struct transport_instance *next;
 134   uschar *name;                   /* Instance name */
 135   struct transport_info *info;    /* Info for this driver */
 136   void *options_block;            /* Pointer to private options */
 137   uschar *driver_name;            /* Must be first */
 138   int   (*setup)(                 /* Setup entry point */
 139     struct transport_instance *,
 140     struct address_item *,
 141     struct transport_feedback *,  /* For passing back config data */
 142     uid_t,                        /* The uid that will be used */
 143     gid_t,                        /* The gid that will be used */
 144     uschar **);                   /* For an error message */
 145                                   /**************************************/
 146   int     batch_max;              /* )                                  */
 147   uschar *batch_id;               /* )                                  */
 148   uschar *home_dir;               /* ) Used only for local transports   */
 149   uschar *current_dir;            /* )                                  */
 150                                   /**************************************/
 151   BOOL    multi_domain;           /* )                                  */
 152   BOOL    overrides_hosts;        /* ) Used only for remote transports  */
 153   int     max_addresses;          /* )                                  */
 154   int     connection_max_messages;/* )                                  */
 155                                   /**************************************/
 156   BOOL    deliver_as_creator;     /* Used only by pipe at present */
 157   BOOL    disable_logging;        /* For very weird requirements */
 158   BOOL    initgroups;             /* Initialize groups when setting uid */
 159   BOOL    uid_set;                /* uid is set */
 160   BOOL    gid_set;                /* gid is set */
 161   uid_t   uid;
 162   gid_t   gid;
 163   uschar *expand_uid;             /* Variable uid */
 164   uschar *expand_gid;             /* Variable gid */
 165   uschar *warn_message;           /* Used only by appendfile at present */
 166   uschar *shadow;                 /* Name of shadow transport */
 167   uschar *shadow_condition;       /* Condition for running it */
 168   uschar *filter_command;         /* For on-the-fly-filtering */
 169   uschar *add_headers;            /* Add these headers */
 170   uschar *remove_headers;         /* Remove these headers */
 171   uschar *return_path;            /* Overriding (rewriting) return path */
 172   uschar *debug_string;           /* Debugging output */
 173   uschar *message_size_limit;     /* Biggest message this transport handles */
 174   uschar *headers_rewrite;        /* Rules for rewriting headers */
 175   rewrite_rule *rewrite_rules;    /* Parsed rewriting rules */
 176   int     rewrite_existflags;     /* Bits showing which headers are rewritten */
 177   int     filter_timeout;         /* For transport filter timing */
 178   BOOL    body_only;              /* Deliver only the body */
 179   BOOL    delivery_date_add;      /* Add Delivery-Date header */
 180   BOOL    envelope_to_add;        /* Add Envelope-To header */
 181   BOOL    headers_only;           /* Deliver only the headers */
 182   BOOL    rcpt_include_affixes;   /* TRUE to retain affixes in RCPT commands */
 183   BOOL    return_path_add;        /* Add Return-Path header */
 184   BOOL    return_output;          /* TRUE if output should always be returned */
 185   BOOL    return_fail_output;     /* ditto, but only on failure */
 186   BOOL    log_output;             /* Similarly for logging */
 187   BOOL    log_fail_output;
 188   BOOL    log_defer_output;
 189   BOOL    retry_use_local_part;   /* Defaults true for local, false for remote */
 190 #ifdef EXPERIMENTAL_TPDA
 191   uschar  *tpda_delivery_action;  /* String to expand on success */
 192 #endif
 193 } transport_instance;
 194
 195
 196 /* Structure for holding information about a type of transport. The first six
 197 fields must match driver_info above. */
 198
 199 typedef struct transport_info {
 200   uschar *driver_name;            /* Driver name */
 201   optionlist *options;            /* Table of private options names */
 202   int    *options_count;          /* -> Number of entries in table */
 203   void   *options_block;          /* Points to default private block */
 204   int     options_len;            /* Length of same in bytes */
 205   void (*init)(                   /* Initialization function */
 206     struct transport_instance *);
 207 /****/
 208   BOOL (*code)(                   /* Main entry point */
 209     transport_instance *,
 210     struct address_item *);
 211   void (*tidyup)(                 /* Tidyup function */
 212     struct transport_instance *);
 213   void  (*closedown)(             /* For closing down a passed channel */
 214     struct transport_instance *);
 215   BOOL    local;                  /* TRUE for local transports */
 216 } transport_info;
 217
 218
 219
 220 /* Structure for holding information about the configured routers. */
 221
 222 typedef struct router_instance {
 223   struct router_instance *next;
 224   uschar *name;
 225   struct router_info *info;
 226   void   *options_block;          /* Pointer to private options */
 227   uschar *driver_name;            /* Must be first */
 228
 229   uschar *address_data;           /* Arbitrary data */
 230 #ifdef EXPERIMENTAL_BRIGHTMAIL
 231   uschar *bmi_rule;               /* Brightmail AntiSpam rule checking */
 232 #endif
 233   uschar *cannot_route_message;   /* Used when routing fails */
 234   uschar *condition;              /* General condition */
 235   uschar *current_directory;      /* For use during delivery */
 236   uschar *debug_string;           /* Debugging output */
 237   uschar *domains;                /* Specific domains */
 238   uschar *errors_to;              /* Errors address */
 239   uschar *expand_gid;             /* Expanded gid string */
 240   uschar *expand_uid;             /* Expanded uid string */
 241   uschar *expand_more;            /* Expanded more string */
 242   uschar *expand_unseen;          /* Expanded unseen string */
 243   uschar *extra_headers;          /* Additional headers */
 244   uschar *fallback_hosts;         /* For remote transports (text list) */
 245   uschar *home_directory;         /* For use during delivery */
 246   uschar *ignore_target_hosts;    /* Target hosts to ignore */
 247   uschar *local_parts;            /* Specific local parts */
 248   uschar *pass_router_name;       /* Router for passed address */
 249   uschar *prefix;                 /* Address prefix */
 250   uschar *redirect_router_name;   /* Router for generated address */
 251   uschar *remove_headers;         /* Removed headers */
 252   uschar *require_files;          /* File checks before router is run */
 253   uschar *router_home_directory;  /* For use while routing */
 254   uschar *self;                   /* Text option for handling self reference */
 255   uschar *senders;                /* Specific senders */
 256   uschar *suffix;                 /* Address suffix */
 257   uschar *translate_ip_address;   /* IP address translation fudgery */
 258   uschar *transport_name;         /* Transport name */
 259
 260   BOOL    address_test;           /* Use this router when testing addresses */
 261 #ifdef EXPERIMENTAL_BRIGHTMAIL
 262   BOOL    bmi_deliver_alternate;  /* TRUE => BMI said that message should be delivered to alternate location */
 263   BOOL    bmi_deliver_default;    /* TRUE => BMI said that message should be delivered to default location */
 264   BOOL    bmi_dont_deliver;       /* TRUE => BMI said that message should not be delivered at all */
 265 #endif
 266   BOOL    expn;                   /* Use this router when processing EXPN */
 267   BOOL    caseful_local_part;     /* TRUE => don't lowercase */
 268   BOOL    check_local_user;       /* TRUE => check local user */
 269   BOOL    disable_logging;        /* For very weird requirements */
 270   BOOL    fail_verify_recipient;  /* Fail verify if recipient match this router */
 271   BOOL    fail_verify_sender;     /* Fail verify if sender match this router */
 272   BOOL    gid_set;                /* Flag to indicate gid is set */
 273   BOOL    initgroups;             /* TRUE if initgroups is required */
 274   BOOL    log_as_local;           /* TRUE logs as a local delivery */
 275   BOOL    more;                   /* If FALSE, do no more if this one fails */
 276   BOOL    pass_on_timeout;        /* Treat timeout DEFERs as fails */
 277   BOOL    prefix_optional;        /* Just what it says */
 278   BOOL    repeat_use;             /* If FALSE, skip if ancestor used it */
 279   BOOL    retry_use_local_part;   /* Just what it says */
 280   BOOL    same_domain_copy_routing; /* TRUE => copy routing for same domain */
 281   BOOL    self_rewrite;           /* TRUE to rewrite headers if making local */
 282   BOOL    suffix_optional;        /* As it says */
 283   BOOL    verify_only;            /* Skip this router if not verifying */
 284   BOOL    verify_recipient;       /* Use this router when verifying a recipient*/
 285   BOOL    verify_sender;          /* Use this router when verifying a sender */
 286   BOOL    uid_set;                /* Flag to indicate uid is set */
 287   BOOL    unseen;                 /* If TRUE carry on, even after success */
 288 #ifdef EXPERIMENTAL_DSN
 289   BOOL    dsn_lasthop;            /* If TRUE, this router is a DSN endpoint */
 290 #endif
 291
 292   int     self_code;              /* Encoded version of "self" */
 293   uid_t   uid;                    /* Fixed uid value */
 294   gid_t   gid;                    /* Fixed gid value */
 295
 296   host_item *fallback_hostlist;   /* For remote transport (block chain) */
 297   transport_instance *transport;  /* Transport block (when found) */
 298   struct router_instance *pass_router; /* Actual router for passed address */
 299   struct router_instance *redirect_router; /* Actual router for generated address */
 300 } router_instance;
 301
 302
 303 /* Structure for holding information about a type of router. The first six
 304 fields must match driver_info above. */
 305
 306 typedef struct router_info {
 307   uschar *driver_name;
 308   optionlist *options;            /* Table of private options names */
 309   int    *options_count;          /* -> Number of entries in table */
 310   void   *options_block;          /* Points to default private block */
 311   int     options_len;            /* Length of same in bytes */
 312   void (*init)(                   /* Initialization function */
 313     struct router_instance *);
 314 /****/
 315   int (*code)(                    /* Main entry point */
 316     router_instance *,
 317     struct address_item *,
 318     struct passwd *,
 319     int,
 320     struct address_item **,
 321     struct address_item **,
 322     struct address_item **,
 323     struct address_item **);
 324   void (*tidyup)(                 /* Tidyup function */
 325     struct router_instance *);
 326   int     ri_flags;               /* Descriptive flags */
 327 } router_info;
 328
 329
 330 /* Structure for holding information about a lookup type. */
 331
 332 #include "lookupapi.h"
 333
 334
 335 /* Structure for holding information about the configured authentication
 336 mechanisms */
 337
 338 typedef struct auth_instance {
 339   struct auth_instance *next;
 340   uschar *name;                   /* Exim instance name */
 341   struct auth_info *info;         /* Pointer to driver info block */
 342   void   *options_block;          /* Pointer to private options */
 343   uschar *driver_name;            /* Must be first */
 344   uschar *advertise_condition;    /* Are we going to advertise this?*/
 345   uschar *client_condition;       /* Should the client try this? */
 346   uschar *public_name;            /* Advertised name */
 347   uschar *set_id;                 /* String to set when server as authenticated id */
 348   uschar *set_client_id;          /* String to set when client as client_authenticated id */
 349   uschar *mail_auth_condition;    /* Condition for AUTH on MAIL command */
 350   uschar *server_debug_string;    /* Debugging output */
 351   uschar *server_condition;       /* Authorization condition */
 352   BOOL    client;                 /* TRUE if client option(s) set */
 353   BOOL    server;                 /* TRUE if server options(s) set */
 354   BOOL    advertised;             /* Set TRUE when advertised */
 355 } auth_instance;
 356
 357
 358 /* Structure for holding information about an authentication mechanism. The
 359 first six fields must match driver_info above. */
 360
 361 typedef struct auth_info {
 362   uschar *driver_name;            /* e.g. "condition" */
 363   optionlist *options;            /* Table of private options names */
 364   int    *options_count;          /* -> Number of entries in table */
 365   void   *options_block;          /* Points to default private block */
 366   int     options_len;            /* Length of same in bytes */
 367   void (*init)(                   /* initialization function */
 368     struct auth_instance *);
 369 /****/
 370   int (*servercode)(              /* server function */
 371     auth_instance *,              /* the instance data */
 372     uschar *);                    /* rest of AUTH command */
 373   int (*clientcode)(              /* client function */
 374     struct auth_instance *,
 375     struct smtp_inblock *,        /* socket and input buffer */
 376     struct smtp_outblock *,       /* socket and output buffer */
 377     int,                          /* command timeout */
 378     uschar *,                     /* buffer for reading response */
 379     int);                         /* sizeof buffer */
 380   void (*version_report)(         /* diagnostic version reporting */
 381     FILE *);                      /* I/O stream to print to */
 382 } auth_info;
 383
 384
 385 /* Structure for holding a single IP address and port; used for the chain of
 386 addresses and ports for the local host. Make the char string large enough to
 387 hold an IPv6 address. */
 388
 389 typedef struct ip_address_item {
 390   struct ip_address_item *next;
 391   int    port;
 392   BOOL   v6_include_v4;            /* Used in the daemon */
 393   uschar address[46];
 394 } ip_address_item;
 395
 396 /* Structure for chaining together arbitrary strings. */
 397
 398 typedef struct string_item {
 399   struct string_item *next;
 400   uschar *text;
 401 } string_item;
 402
 403 /* Information about a soft delivery failure, for use when calculating
 404 retry information. It's separate from the address block, because there
 405 can be a chain of them for SMTP deliveries where multiple IP addresses
 406 can be tried. */
 407
 408 typedef struct retry_item {
 409   struct retry_item *next;        /* for chaining */
 410   uschar *key;                    /* string identifying host/address/message */
 411   int     basic_errno;            /* error code for this destination */
 412   int     more_errno;             /* additional error information */
 413   uschar *message;                /* local error message */
 414   int     flags;                  /* see below */
 415 } retry_item;
 416
 417 /* Retry data flags */
 418
 419 #define rf_delete   0x0001        /* retry info is to be deleted */
 420 #define rf_host     0x0002        /* retry info is for a remote host */
 421 #define rf_message  0x0004        /* retry info is for a host+message */
 422
 423 /* Information about a constructed message that is to be sent using the
 424 autoreply transport. This is pointed to from the address block. */
 425
 426 typedef struct reply_item {
 427   uschar *from;                   /* ) */
 428   uschar *reply_to;               /* ) */
 429   uschar *to;                     /* ) */
 430   uschar *cc;                     /* ) specific header fields */
 431   uschar *bcc;                    /* ) */
 432   uschar *subject;                /* ) */
 433   uschar *headers;                /* misc other headers, concatenated */
 434   uschar *text;                   /* text string body */
 435   uschar *file;                   /* file body */
 436   BOOL    file_expand;            /* expand the body */
 437   int     expand_forbid;          /* expansion lockout flags */
 438   uschar *logfile;                /* file to keep a log in */
 439   uschar *oncelog;                /* file to keep records in for once only */
 440   time_t  once_repeat;            /* time to repeat "once only" */
 441   BOOL    return_message;         /* send back the original message */
 442 } reply_item;
 443
 444
 445 /* The address_item structure contains many fields which are used at various
 446 times while delivering a message. Some are used only for remote deliveries;
 447 some only for local. A particular set of fields is copied whenever a child
 448 address is created. For convenience, we keep those fields in a separate
 449 sub-structure so they can be copied in one go. This also means I won't forget
 450 to edit the various copying places when new to-be-copied fields are added. */
 451
 452 typedef struct address_item_propagated {
 453   uschar *address_data;           /* arbitrary data to keep with the address */
 454   uschar *domain_data;            /* from "domains" lookup */
 455   uschar *localpart_data;         /* from "local_parts" lookup */
 456   uschar *errors_address;         /* where to send errors (NULL => sender) */
 457   header_line *extra_headers;     /* additional headers */
 458   uschar *remove_headers;         /* list of those to remove */
 459
 460   #ifdef EXPERIMENTAL_SRS
 461   uschar *srs_sender;             /* Change return path when delivering */
 462   #endif
 463 } address_item_propagated;
 464
 465 /* Bits for the flags field below */
 466
 467 #define af_allow_file          0x00000001 /* allow file in generated address */
 468 #define af_allow_pipe          0x00000002 /* allow pipe in generated address */
 469 #define af_allow_reply         0x00000004 /* allow autoreply in generated address */
 470 #define af_dr_retry_exists     0x00000008 /* router retry record exists */
 471 #define af_expand_pipe         0x00000010 /* expand pipe arguments */
 472 #define af_file                0x00000020 /* file delivery; always with pfr */
 473 #define af_gid_set             0x00000040 /* gid field is set */
 474 #define af_home_expanded       0x00000080 /* home_dir is already expanded */
 475 #define af_ignore_error        0x00000100 /* ignore delivery error */
 476 #define af_initgroups          0x00000200 /* use initgroups() for local transporting */
 477 #define af_local_host_removed  0x00000400 /* local host was backup */
 478 #define af_lt_retry_exists     0x00000800 /* local transport retry exists */
 479 #define af_pfr                 0x00001000 /* pipe or file or reply delivery */
 480 #define af_retry_skipped       0x00002000 /* true if retry caused some skipping */
 481 #define af_retry_timedout      0x00004000 /* true if retry timed out */
 482 #define af_uid_set             0x00008000 /* uid field is set */
 483 #define af_hide_child          0x00010000 /* hide child in bounce/defer msgs */
 484 #define af_sverify_told        0x00020000 /* sender verify failure notified */
 485 #define af_verify_pmfail       0x00040000 /* verify failure was postmaster callout */
 486 #define af_verify_nsfail       0x00080000 /* verify failure was null sender callout */
 487 #define af_homonym             0x00100000 /* an ancestor has same address */
 488 #define af_verify_routed       0x00200000 /* for cached sender verify: routed OK */
 489 #define af_verify_callout      0x00400000 /* for cached sender verify: callout was specified */
 490 #define af_include_affixes     0x00800000 /* delivered with affixes in RCPT */
 491 #define af_cert_verified       0x01000000 /* delivered with verified TLS cert */
 492 #define af_pass_message        0x02000000 /* pass message in bounces */
 493 #define af_bad_reply           0x04000000 /* filter could not generate autoreply */
 494 #ifndef DISABLE_PRDR
 495 # define af_prdr_used          0x08000000 /* delivery used SMTP PRDR */
 496 #endif
 497 #define af_force_command       0x10000000 /* force_command in pipe transport */
 498
 499 /* These flags must be propagated when a child is created */
 500
 501 #define af_propagate           (af_ignore_error)
 502
 503 /* The main address structure. Note that fields that are to be copied to
 504 generated addresses should be put in the address_item_propagated structure (see
 505 above) rather than directly into the address_item structure. */
 506
 507 typedef struct address_item {
 508   struct address_item *next;      /* for chaining addresses */
 509   struct address_item *parent;    /* parent address */
 510   struct address_item *first;     /* points to first after group delivery */
 511   struct address_item *dupof;     /* points to address this is a duplicate of */
 512
 513   router_instance *start_router;  /* generated address starts here */
 514   router_instance *router;        /* the router that routed */
 515   transport_instance *transport;  /* the transport to use */
 516
 517   host_item *host_list;           /* host data for the transport */
 518   host_item *host_used;           /* host that took delivery or failed hard */
 519   host_item *fallback_hosts;      /* to try if delivery defers */
 520
 521   reply_item *reply;              /* data for autoreply */
 522   retry_item *retries;            /* chain of retry information */
 523
 524   uschar *address;                /* address being delivered or routed */
 525   uschar *unique;                 /* used for disambiguating */
 526   uschar *cc_local_part;          /* caseful local part */
 527   uschar *lc_local_part;          /* lowercased local part */
 528   uschar *local_part;             /* points to cc or lc version */
 529   uschar *prefix;                 /* stripped prefix of local part */
 530   uschar *suffix;                 /* stripped suffix of local part */
 531   uschar *domain;                 /* working domain (lower cased) */
 532
 533   uschar *address_retry_key;      /* retry key including full address */
 534   uschar *domain_retry_key;       /* retry key for domain only */
 535
 536   uschar *current_dir;            /* current directory for transporting */
 537   uschar *home_dir;               /* home directory for transporting */
 538   uschar *message;                /* error message */
 539   uschar *user_message;           /* error message that can be sent over SMTP
 540                                      or quoted in bounce message */
 541   uschar *onetime_parent;         /* saved original parent for onetime */
 542   uschar **pipe_expandn;          /* numeric expansions for pipe from filter */
 543   uschar *return_filename;        /* name of return file */
 544   uschar *self_hostname;          /* after self=pass */
 545   uschar *shadow_message;         /* info about shadow transporting */
 546
 547   #ifdef SUPPORT_TLS
 548   uschar *cipher;                 /* Cipher used for transport */
 549   void   *ourcert;                /* Certificate offered to peer, binary */
 550   void   *peercert;               /* Certificate from peer, binary */
 551   uschar *peerdn;                 /* DN of server's certificate */
 552   int    ocsp;                    /* OCSP status of peer cert */
 553   #endif
 554
 555   uschar *authenticator;          /* auth driver name used by transport */
 556   uschar *auth_id;                /* auth "login" name used by transport */
 557   uschar *auth_sndr;              /* AUTH arg to SMTP MAIL, used by transport */
 558
 559   #ifdef EXPERIMENTAL_DSN
 560   uschar *dsn_orcpt;              /* DSN orcpt value */
 561   int     dsn_flags;              /* DSN flags */
 562   int     dsn_aware;              /* DSN aware flag */
 563   #endif
 564
 565   uid_t   uid;                    /* uid for transporting */
 566   gid_t   gid;                    /* gid for transporting */
 567
 568   unsigned int flags;             /* a row of bits, defined above */
 569   unsigned int domain_cache[(MAX_NAMED_LIST * 2)/32];
 570   unsigned int localpart_cache[(MAX_NAMED_LIST * 2)/32];
 571   int     mode;                   /* mode for local transporting to a file */
 572   int     more_errno;             /* additional error information */
 573                                   /* (may need to hold a timestamp) */
 574
 575   short int basic_errno;          /* status after failure */
 576   short int child_count;          /* number of child addresses */
 577   short int return_file;          /* fileno of return data file */
 578   short int special_action;       /* ( used when when deferred or failed */
 579                                   /* (  also  */
 580                                   /* ( contains = or - when successful SMTP delivered */
 581                                   /* (  also  */
 582                                   /* ( contains verify rc in sender verify cache */
 583   short int transport_return;     /* result of delivery attempt */
 584   address_item_propagated p;      /* fields that are propagated to children */
 585 } address_item;
 586
 587 /* The table of header names consists of items of this type */
 588
 589 typedef struct {
 590   uschar *name;
 591   int     len;
 592   BOOL    allow_resent;
 593   int     htype;
 594 } header_name;
 595
 596 /* Chain of information about errors (e.g. bad addresses) */
 597
 598 typedef struct error_block {
 599   struct error_block *next;
 600   uschar *text1;
 601   uschar *text2;
 602 } error_block;
 603
 604 /* Chain of file names when processing the queue */
 605
 606 typedef struct queue_filename {
 607   struct queue_filename *next;
 608   uschar dir_uschar;
 609   uschar text[1];
 610 } queue_filename;
 611
 612 /* Chain of items of retry information, read from the retry config. */
 613
 614 typedef struct retry_rule {
 615   struct retry_rule *next;
 616   int    rule;
 617   int    timeout;
 618   int    p1;
 619   int    p2;
 620 } retry_rule;
 621
 622 typedef struct retry_config {
 623   struct retry_config *next;
 624   uschar *pattern;
 625   int     basic_errno;
 626   int     more_errno;
 627   uschar *senders;
 628   retry_rule *rules;
 629 } retry_config;
 630
 631 /* Structure for each node in a tree, of which there are various kinds */
 632
 633 typedef struct tree_node {
 634   struct tree_node *left;         /* pointer to left child */
 635   struct tree_node *right;        /* pointer to right child */
 636   union
 637     {
 638     void  *ptr;                   /* pointer to data */
 639     int val;                      /* or integer data */
 640     } data;
 641   uschar  balance;                /* balancing factor */
 642   uschar  name[1];                /* node name - variable length */
 643 } tree_node;
 644
 645 /* Structure for holding the handle and the cached last lookup for searches.
 646 This block is pointed to by the tree entry for the file. The file can get
 647 closed if too many are opened at once. There is a LRU chain for deciding which
 648 to close. */
 649
 650 typedef struct search_cache {
 651   void   *handle;                 /* lookup handle, or NULL if closed */
 652   int search_type;                /* search type */
 653   tree_node *up;                  /* LRU up pointer */
 654   tree_node *down;                /* LRU down pointer */
 655   tree_node *item_cache;          /* tree of cached results */
 656 } search_cache;
 657
 658 /* Structure for holding a partially decoded DNS record; the name has been
 659 uncompressed, but the data pointer is into the raw data. */
 660
 661 typedef struct {
 662   uschar  name[DNS_MAXNAME];      /* domain name */
 663   int     type;                   /* record type */
 664   int     size;                   /* size of data */
 665   uschar *data;                   /* pointer to data */
 666 } dns_record;
 667
 668 /* Structure for holding the result of a DNS query. */
 669
 670 typedef struct {
 671   int     answerlen;              /* length of the answer */
 672   uschar  answer[MAXPACKET];      /* the answer itself */
 673 } dns_answer;
 674
 675 /* Structure for holding the intermediate data while scanning a DNS answer
 676 block. */
 677
 678 typedef struct {
 679   int     rrcount;                /* count of RRs in the answer */
 680   uschar *aptr;                   /* pointer in the answer while scanning */
 681   dns_record srr;                 /* data from current record in scan */
 682 } dns_scan;
 683
 684 /* Structure for holding a chain of IP addresses that are extracted from
 685 an A, AAAA, or A6 record. For the first two, there is only ever one address,
 686 but the chaining feature of A6 allows for several addresses to be realized from
 687 a single initial A6 record. The structure defines the address field of length
 688 1. In use, a suitable sized block is obtained to hold the complete textual
 689 address. */
 690
 691 typedef struct dns_address {
 692   struct dns_address *next;
 693   uschar  address[1];
 694 } dns_address;
 695
 696 /* Structure used for holding intermediate data during MD5 computations. */
 697
 698 typedef struct md5 {
 699   unsigned int length;
 700   unsigned int abcd[4];
 701   }
 702 md5;
 703
 704 /* Structure used for holding intermediate data during SHA-1 computations. */
 705
 706 typedef struct sha1 {
 707   unsigned int H[5];
 708   unsigned int length;
 709   }
 710 sha1;
 711
 712 /* Structure used to hold incoming packets of SMTP responses for a specific
 713 socket. The packets which may contain multiple lines (and in some cases,
 714 multiple responses). */
 715
 716 typedef struct smtp_inblock {
 717   int     sock;                   /* the socket */
 718   int     buffersize;             /* the size of the buffer */
 719   uschar *ptr;                    /* current position in the buffer */
 720   uschar *ptrend;                 /* end of data in the buffer */
 721   uschar *buffer;                 /* the buffer itself */
 722 } smtp_inblock;
 723
 724 /* Structure used to hold buffered outgoing packets of SMTP commands for a
 725 specific socket. The packets which may contain multiple lines when pipelining
 726 is in use. */
 727
 728 typedef struct smtp_outblock {
 729   int     sock;                   /* the socket */
 730   int     cmd_count;              /* count of buffered commands */
 731   int     buffersize;             /* the size of the buffer */
 732   BOOL    authenticating;         /* TRUE when authenticating */
 733   uschar *ptr;                    /* current position in the buffer */
 734   uschar *buffer;                 /* the buffer itself */
 735 } smtp_outblock;
 736
 737 /* Structure to hold information about the source of redirection information */
 738
 739 typedef struct redirect_block {
 740   uschar *string;                 /* file name or string */
 741   uid_t  *owners;                 /* allowed file owners */
 742   gid_t  *owngroups;              /* allowed file groups */
 743   struct passwd *pw;              /* possible owner if not NULL */
 744   int     modemask;               /* forbidden bits */
 745   BOOL    isfile;                 /* TRUE if string is a file name */
 746   BOOL    check_owner;            /* TRUE, FALSE, or TRUE_UNSET */
 747   BOOL    check_group;            /* TRUE, FALSE, or TRUE_UNSET */
 748 } redirect_block;
 749
 750 /* Structure for passing arguments to check_host() */
 751
 752 typedef struct check_host_block {
 753   uschar *host_name;
 754   uschar *host_address;
 755   uschar *host_ipv4;
 756   BOOL   negative;
 757 } check_host_block;
 758
 759 /* Structure for remembering lookup data when caching the result of
 760 a lookup in a named list. */
 761
 762 typedef struct namedlist_cacheblock {
 763   struct namedlist_cacheblock *next;
 764   uschar *key;
 765   uschar *data;
 766 } namedlist_cacheblock;
 767
 768 /* Structure for holding data for an entry in a named list */
 769
 770 typedef struct namedlist_block {
 771   uschar *string;                    /* the list string */
 772   namedlist_cacheblock *cache_data;  /* cached domain_data or localpart_data */
 773   int number;                        /* the number of the list for caching */
 774 } namedlist_block;
 775
 776 /* Structures for Access Control Lists */
 777
 778 typedef struct acl_condition_block {
 779   struct acl_condition_block *next;
 780   uschar *arg;
 781   int type;
 782   union {
 783     BOOL negated;
 784     uschar *varname;
 785   } u;
 786 } acl_condition_block;
 787
 788 typedef struct acl_block {
 789   struct acl_block *next;
 790   acl_condition_block *condition;
 791   int verb;
 792 } acl_block;
 793
 794 /* End of structs.h */