external/ibm-public/postfix/dist/src/cleanup/cleanup_out.c

   1 /*      $NetBSD$        */
   2
   3 /*++
   4 /* NAME
   5 /*      cleanup_out 3
   6 /* SUMMARY
   7 /*      record output support
   8 /* SYNOPSIS
   9 /*      #include "cleanup.h"
  10 /*
  11 /*      int     CLEANUP_OUT_OK(state)
  12 /*      CLEANUP_STATE *state;
  13 /*
  14 /*      void    cleanup_out(state, type, data, len)
  15 /*      CLEANUP_STATE *state;
  16 /*      int     type;
  17 /*      const char *data;
  18 /*      ssize_t len;
  19 /*
  20 /*      void    cleanup_out_string(state, type, str)
  21 /*      CLEANUP_STATE *state;
  22 /*      int     type;
  23 /*      const char *str;
  24 /*
  25 /*      void    CLEANUP_OUT_BUF(state, type, buf)
  26 /*      CLEANUP_STATE *state;
  27 /*      int     type;
  28 /*      VSTRING *buf;
  29 /*
  30 /*      void    cleanup_out_format(state, type, format, ...)
  31 /*      CLEANUP_STATE *state;
  32 /*      int     type;
  33 /*      const char *format;
  34 /*
  35 /*      void    cleanup_out_header(state, buf)
  36 /*      CLEANUP_STATE *state;
  37 /*      VSTRING *buf;
  38 /* DESCRIPTION
  39 /*      This module writes records to the output stream.
  40 /*
  41 /*      CLEANUP_OUT_OK() is a macro that evaluates to non-zero
  42 /*      as long as it makes sense to produce output. All output
  43 /*      routines below check for this condition.
  44 /*
  45 /*      cleanup_out() is the main record output routine. It writes
  46 /*      one record of the specified type, with the specified data
  47 /*      and length to the output stream.
  48 /*
  49 /*      cleanup_out_string() outputs one string as a record.
  50 /*
  51 /*      CLEANUP_OUT_BUF() is an unsafe macro that outputs
  52 /*      one string buffer as a record.
  53 /*
  54 /*      cleanup_out_format() formats its arguments and writes
  55 /*      the result as a record.
  56 /*
  57 /*      cleanup_out_header() outputs a multi-line header as records
  58 /*      of the specified type. The input is expected to be newline
  59 /*      separated (not newline terminated), and is modified.
  60 /* LICENSE
  61 /* .ad
  62 /* .fi
  63 /*      The Secure Mailer license must be distributed with this software.
  64 /* AUTHOR(S)
  65 /*      Wietse Venema
  66 /*      IBM T.J. Watson Research
  67 /*      P.O. Box 704
  68 /*      Yorktown Heights, NY 10598, USA
  69 /*--*/
  70
  71 /* System library. */
  72
  73 #include <sys_defs.h>
  74 #include <errno.h>
  75 #include <stdlib.h>                     /* 44BSD stdarg.h uses abort() */
  76 #include <stdarg.h>
  77 #include <string.h>
  78
  79 /* Utility library. */
  80
  81 #include <msg.h>
  82 #include <vstring.h>
  83 #include <vstream.h>
  84 #include <split_at.h>
  85
  86 /* Global library. */
  87
  88 #include <record.h>
  89 #include <rec_type.h>
  90 #include <cleanup_user.h>
  91 #include <mail_params.h>
  92 #include <lex_822.h>
  93
  94 /* Application-specific. */
  95
  96 #include "cleanup.h"
  97
  98 /* cleanup_out - output one single record */
  99
 100 void    cleanup_out(CLEANUP_STATE *state, int type, const char *string, ssize_t len)
 101 {
 102     int     err = 0;
 103
 104     /*
 105      * Long message header lines have to be read and written as multiple
 106      * records. Other header/body content, and envelope data, is copied one
 107      * record at a time. Be sure to not skip a zero-length request.
 108      *
 109      * XXX We don't know if we're writing a message header or not, but that is
 110      * not a problem. A REC_TYPE_NORM or REC_TYPE_CONT record can always be
 111      * chopped up into an equivalent set of REC_TYPE_CONT plus REC_TYPE_NORM
 112      * records.
 113      */
 114     if (CLEANUP_OUT_OK(state) == 0)
 115         return;
 116
 117 #define TEXT_RECORD(t)  ((t) == REC_TYPE_NORM || (t) == REC_TYPE_CONT)
 118
 119     if (var_line_limit <= 0)
 120         msg_panic("cleanup_out: bad line length limit: %d", var_line_limit);
 121     do {
 122         if (len > var_line_limit && TEXT_RECORD(type)) {
 123             err = rec_put(state->dst, REC_TYPE_CONT, string, var_line_limit);
 124             string += var_line_limit;
 125             len -= var_line_limit;
 126         } else {
 127             err = rec_put(state->dst, type, string, len);
 128             break;
 129         }
 130     } while (len > 0 && err >= 0);
 131
 132     if (err < 0) {
 133         if (errno == EFBIG) {
 134             msg_warn("%s: queue file size limit exceeded",
 135                      state->queue_id);
 136             state->errs |= CLEANUP_STAT_SIZE;
 137         } else {
 138             msg_warn("%s: write queue file: %m", state->queue_id);
 139             state->errs |= CLEANUP_STAT_WRITE;
 140         }
 141     }
 142 }
 143
 144 /* cleanup_out_string - output string to one single record */
 145
 146 void    cleanup_out_string(CLEANUP_STATE *state, int type, const char *string)
 147 {
 148     cleanup_out(state, type, string, strlen(string));
 149 }
 150
 151 /* cleanup_out_format - output one formatted record */
 152
 153 void    cleanup_out_format(CLEANUP_STATE *state, int type, const char *fmt,...)
 154 {
 155     static VSTRING *vp;
 156     va_list ap;
 157
 158     if (vp == 0)
 159         vp = vstring_alloc(100);
 160     va_start(ap, fmt);
 161     vstring_vsprintf(vp, fmt, ap);
 162     va_end(ap);
 163     CLEANUP_OUT_BUF(state, type, vp);
 164 }
 165
 166 /* cleanup_out_header - output one multi-line header as a bunch of records */
 167
 168 void    cleanup_out_header(CLEANUP_STATE *state, VSTRING *header_buf)
 169 {
 170     char   *start = vstring_str(header_buf);
 171     char   *line;
 172     char   *next_line;
 173     ssize_t line_len;
 174
 175     /*
 176      * Prepend a tab to continued header lines that went through the address
 177      * rewriting machinery. See cleanup_fold_header(state) below for the form
 178      * of such header lines. NB: This code destroys the header. We could try
 179      * to avoid clobbering it, but we're not going to use the data any
 180      * further.
 181      *
 182      * XXX We prefer to truncate a header at the last line boundary before the
 183      * header size limit. If this would undershoot the limit by more than
 184      * 10%, we truncate between line boundaries to avoid losing too much
 185      * text. This "unkind cut" may result in syntax errors and may trigger
 186      * warnings from down-stream MTAs.
 187      *
 188      * If Milter is enabled, pad a short header record with a dummy record so
 189      * that a header record can safely be overwritten by a pointer record.
 190      * This simplifies header modification enormously.
 191      */
 192     for (line = start; line; line = next_line) {
 193         next_line = split_at(line, '\n');
 194         line_len = next_line ? next_line - 1 - line : strlen(line);
 195         if (line + line_len > start + var_header_limit) {
 196             if (line - start > 0.9 * var_header_limit)  /* nice cut */
 197                 break;
 198             start[var_header_limit] = 0;        /* unkind cut */
 199             next_line = 0;
 200         }
 201         if (line == start) {
 202             cleanup_out_string(state, REC_TYPE_NORM, line);
 203             if ((state->milters || cleanup_milters)
 204                 && line_len < REC_TYPE_PTR_PAYL_SIZE)
 205                 rec_pad(state->dst, REC_TYPE_DTXT,
 206                         REC_TYPE_PTR_PAYL_SIZE - line_len);
 207         } else if (IS_SPACE_TAB(*line)) {
 208             cleanup_out_string(state, REC_TYPE_NORM, line);
 209         } else {
 210             cleanup_out_format(state, REC_TYPE_NORM, "\t%s", line);
 211         }
 212     }
 213 }