src/src/local_scan.h

   1 /*************************************************
   2 *     Exim - an Internet mail transport agent    *
   3 *************************************************/
   4
   5 /* Copyright (c) University of Cambridge 1995 - 2020 */
   6 /* See the file NOTICE for conditions of use and distribution. */
   7
   8 /* This file is the header that is the only Exim header to be included in the
   9 source for the local_scan.c() function. It contains definitions that are made
  10 available for use in that function, and which are documented.  That source
  11 should first #define LOCAL_SCAN
  12
  13 Not every definition that becomes available to the compiler by the inclusion
  14 of this file is part of the local_scan API.  The "Adding a local scan function
  15 to Exim" chapter in the documentation is definitive.
  16
  17 This API is also used for functions called by the ${dlfunc expansion item.
  18 Source for those should first #define DLFUNC_IMPL and then include this file.
  19 Coders of dlfunc routines should read the notes on tainting at the start of
  20 store.c
  21 */
  22
  23
  24 /* Some basic types that make some things easier, the Exim configuration
  25 settings, and the store functions. */
  26
  27 #include <stdarg.h>
  28 #include <sys/types.h>
  29 #include "config.h"
  30 #include "mytypes.h"
  31 #include "store.h"
  32
  33
  34 /* The function and its return codes. */
  35
  36 extern int local_scan(int, uschar **);
  37
  38 enum {
  39   LOCAL_SCAN_ACCEPT,              /* Accept */
  40   LOCAL_SCAN_ACCEPT_FREEZE,       /* Accept, but freeze */
  41   LOCAL_SCAN_ACCEPT_QUEUE,        /* Accept, but no immediate delivery */
  42   LOCAL_SCAN_REJECT,              /* Permanent rejection */
  43   LOCAL_SCAN_REJECT_NOLOGHDR,     /* Permanent rejection, no log header */
  44   LOCAL_SCAN_TEMPREJECT,          /* Temporary rejection */
  45   LOCAL_SCAN_TEMPREJECT_NOLOGHDR  /* Temporary rejection, no log header */
  46 };
  47
  48
  49 /* Functions called by ${dlfunc{file}{func}{arg}...} return one of the five
  50 status codes defined immediately below. The function's first argument is either
  51 the result of expansion, or the error message in case of failure. The second
  52 and third arguments are standard argument count and vector, comprising the
  53 {arg} values specified in the expansion item. */
  54
  55 typedef int exim_dlfunc_t(uschar **yield, int argc, uschar *argv[]);
  56
  57
  58 /* Return codes from the support functions lss_match_xxx(). These are also the
  59 codes that dynamically-loaded ${dlfunc functions must return. */
  60
  61 #define  OK            0          /* Successful match */
  62 #define  DEFER         1          /* Defer - some problem */
  63 #define  FAIL          2          /* Matching failed */
  64 #define  ERROR         3          /* Internal or config error */
  65
  66 /* Extra return code for ${dlfunc functions */
  67
  68 #define  FAIL_FORCED   4          /* "Forced" failure */
  69
  70
  71 /* Available logging destinations */
  72
  73 #define LOG_MAIN        1    /* Write to the main log */
  74 #define LOG_PANIC       2    /* Write to the panic log */
  75 #define LOG_REJECT     16    /* Write to the reject log, with headers */
  76
  77
  78 /* Accessible debugging bits */
  79
  80 #define D_v                          0x00000001
  81 #define D_local_scan                 0x00000002
  82
  83
  84 /* Option types that can be used for local_scan_options. The boolean ones
  85 MUST be last so that they are contiguous with the internal boolean specials. */
  86
  87 enum { opt_stringptr, opt_int, opt_octint, opt_mkint, opt_Kint, opt_fixed,
  88   opt_time, opt_bool };
  89
  90
  91 /* The length of message identification strings. This is the id used internally
  92 by exim. The external version for use in Received: strings has a leading 'E'
  93 added to ensure it starts with a letter. */
  94
  95 #define MESSAGE_ID_LENGTH 16
  96
  97 /* The offset to the start of the data in the data file - this allows for
  98 the name of the data file to be present in the first line. */
  99
 100 #define SPOOL_DATA_START_OFFSET (MESSAGE_ID_LENGTH+3)
 101
 102 /* Some people (Marc Merlin et al) are maintaining a patch that allows for
 103 dynamic local_scan() libraries. This code is not yet in Exim proper, but it
 104 helps the maintainers if we keep their ABI version numbers here. This may
 105 mutate into more general support later. The major number is increased when the
 106 ABI is changed in a non backward compatible way. The minor number is increased
 107 each time a new feature is added (in a way that doesn't break backward
 108 compatibility). */
 109
 110 #define LOCAL_SCAN_ABI_VERSION_MAJOR 4
 111 #define LOCAL_SCAN_ABI_VERSION_MINOR 0
 112 #define LOCAL_SCAN_ABI_VERSION \
 113   LOCAL_SCAN_ABI_VERSION_MAJOR.LOCAL_SCAN_ABI_VERSION_MINOR
 114
 115 /* Structure definitions that are documented as visible in the function. */
 116
 117 typedef struct header_line {
 118   struct header_line *next;
 119   int    type;
 120   int    slen;
 121   uschar *text;
 122 } header_line;
 123
 124 /* Entries in lists options are in this form. */
 125
 126 typedef struct {
 127   const char *  name; /* should have been uschar but too late now */
 128   int           type;
 129   union {
 130     void *      value;
 131     long        offset;
 132     void (*     fn)();
 133   } v;
 134 } optionlist;
 135 #define OPT_OFF(s, field) {.offset = offsetof(s, field)}
 136
 137 /* Structure for holding information about an envelope address. The errors_to
 138 field is always NULL except for one_time aliases that had errors_to on the
 139 routers that generated them. */
 140
 141 typedef struct recipient_item {
 142   uschar *address;              /* the recipient address */
 143   int     pno;                  /* parent number for "one_time" alias, or -1 */
 144   uschar *errors_to;            /* the errors_to address or NULL */
 145   uschar *orcpt;                /* DSN orcpt */
 146   int     dsn_flags;            /* DSN flags */
 147 #ifdef EXPERIMENTAL_BRIGHTMAIL
 148   uschar *bmi_optin;
 149 #endif
 150 } recipient_item;
 151
 152
 153 /* Global variables that are documented as visible in the function. */
 154
 155 extern unsigned int debug_selector;    /* Debugging bits */
 156
 157 extern int     body_linecount;         /* Line count in body */
 158 extern int     body_zerocount;         /* Binary zero count in body */
 159 extern uschar *expand_string_message;  /* Error info for failing expansion */
 160 extern uschar *headers_charset;        /* Charset for RFC 2047 decoding */
 161 extern header_line *header_last;       /* Final header */
 162 extern header_line *header_list;       /* First header */
 163 extern BOOL    host_checking;          /* Set when checking a host */
 164 extern uschar *interface_address;      /* Interface for incoming call */
 165 extern int     interface_port;         /* Port number for incoming call */
 166 extern uschar *message_id;             /* Internal id of message being handled */
 167 extern uschar *received_protocol;      /* Name of incoming protocol */
 168 extern int     recipients_count;       /* Number of recipients */
 169 extern recipient_item *recipients_list;/* List of recipient addresses */
 170 extern unsigned char *sender_address;  /* Sender address */
 171 extern uschar *sender_host_address;    /* IP address of sender, as chars */
 172 extern uschar *sender_host_authenticated; /* Name of authentication mechanism */
 173 extern uschar *sender_host_name;       /* Host name from lookup */
 174 extern int     sender_host_port;       /* Port number of sender */
 175 extern BOOL    smtp_batched_input;     /* TRUE if SMTP batch (no interaction) */
 176 extern BOOL    smtp_input;             /* TRUE if input is via SMTP */
 177
 178
 179 /* Functions that are documented as visible in local_scan(). */
 180
 181 extern int     child_close(pid_t, int);
 182 extern pid_t   child_open(uschar **, uschar **, int, int *, int *, BOOL);
 183 extern pid_t   child_open_exim(int *);
 184 extern pid_t   child_open_exim2(int *, uschar *, uschar *);
 185 extern void    debug_printf(const char *, ...) PRINTF_FUNCTION(1,2);
 186 extern uschar *expand_string(uschar *);
 187 extern void    header_add(int, const char *, ...);
 188 extern void    header_add_at_position(BOOL, uschar *, BOOL, int, const char *, ...);
 189 extern void    header_remove(int, const uschar *);
 190 extern BOOL    header_testname(header_line *, const uschar *, int, BOOL);
 191 extern BOOL    header_testname_incomplete(header_line *, const uschar *, int, BOOL);
 192 extern void    log_write(unsigned int, int, const char *format, ...) PRINTF_FUNCTION(3,4);
 193 extern int     lss_b64decode(uschar *, uschar **);
 194 extern uschar *lss_b64encode(uschar *, int);
 195 extern int     lss_match_domain(uschar *, uschar *);
 196 extern int     lss_match_local_part(uschar *, uschar *, BOOL);
 197 extern int     lss_match_address(uschar *, uschar *, BOOL);
 198 extern int     lss_match_host(uschar *, uschar *, uschar *);
 199 extern void    receive_add_recipient(uschar *, int);
 200 extern BOOL    receive_remove_recipient(uschar *);
 201 extern uschar *rfc2047_decode(uschar *, BOOL, uschar *, int, int *, uschar **);
 202 extern int     smtp_fflush(void);
 203 extern void    smtp_printf(const char *, BOOL, ...) PRINTF_FUNCTION(1,3);
 204 extern void    smtp_vprintf(const char *, BOOL, va_list);
 205
 206 #define string_sprintf(fmt, ...) \
 207         string_sprintf_trc(fmt, US __FUNCTION__, __LINE__, __VA_ARGS__)
 208 extern uschar *string_sprintf_trc(const char *, const uschar *, unsigned, ...) ALMOST_PRINTF(1,4);
 209
 210 #define store_get(size, tainted) \
 211         store_get_3(size, tainted, __FUNCTION__, __LINE__)
 212 extern void   *store_get_3(int, BOOL, const char *, int)        ALLOC ALLOC_SIZE(1) WARN_UNUSED_RESULT;
 213 #define store_get_perm(size, tainted) \
 214         store_get_perm_3(size, tainted, __FUNCTION__, __LINE__)
 215 extern void   *store_get_perm_3(int, BOOL, const char *, int)   ALLOC ALLOC_SIZE(1) WARN_UNUSED_RESULT;
 216
 217
 218 #if defined(LOCAL_SCAN) || defined(DLFUNC_IMPL)
 219 /* When compiling a local_scan() file we want to rename a published API, so that
 220 we can use an inlined implementation in the compiles of the main Exim files,
 221 with the original name. */
 222
 223 # define string_copy(s) string_copy_function(s)
 224 # define string_copyn(s, n) string_copyn_function((s), (n))
 225 # define string_copy_taint(s, t) string_copy_taint_function((s), (t))
 226
 227 extern uschar * string_copy_function(const uschar *);
 228 extern uschar * string_copyn_function(const uschar *, int n);
 229 extern uschar * string_copy_taint_function(const uschar *, BOOL tainted);
 230 #endif
 231
 232 /* End of local_scan.h */