sendmail-dtelnet.patch

   1 diff -Nur sendmail-8.12.0.orig/sendmail/conf.c sendmail-8.12.0/sendmail/conf.c
   2 --- sendmail-8.12.0.orig/sendmail/conf.c        Wed Sep  5 00:43:02 2001
   3 +++ sendmail-8.12.0/sendmail/conf.c     Mon Sep 24 10:01:52 2001
   4 @@ -326,6 +326,8 @@
   5         DontLockReadFiles = true;
   6         DontProbeInterfaces = DPI_PROBEALL;
   7         DoubleBounceAddr = "postmaster";
   8 +       DetectTelnet = 0;
   9 +       ExitOnTelnet = 1;
  10         MaxHeadersLength = MAXHDRSLEN;
  11         MaxForwardEntries = 0;
  12         FastSplit = 1;
  13 diff -Nur sendmail-8.12.0.orig/sendmail/err.c sendmail-8.12.0/sendmail/err.c
  14 --- sendmail-8.12.0.orig/sendmail/err.c Wed Sep  5 00:43:03 2001
  15 +++ sendmail-8.12.0/sendmail/err.c      Mon Sep 24 10:02:57 2001
  16 @@ -909,15 +909,17 @@
  17                 (void) sm_strlcpyn(eb, spaceleft, 2,
  18                                    shortenstring(to, MAXSHORTSTR), "... ");
  19                 spaceleft -= strlen(eb);
  20 -               while (*eb != '\0')
  21 -                       *eb++ &= 0177;
  22 +               if(!DetectTelnet)
  23 +                       while (*eb != '\0')
  24 +                               *eb++ &= 0177;
  25         }
  26
  27         /* output the message */
  28         (void) sm_vsnprintf(eb, spaceleft, fmt, ap);
  29         spaceleft -= strlen(eb);
  30 -       while (*eb != '\0')
  31 -               *eb++ &= 0177;
  32 +       if(!DetectTelnet)
  33 +               while (*eb != '\0')
  34 +                       *eb++ &= 0177;
  35
  36         /* output the error code, if any */
  37         if (eno != 0)
  38 diff -Nur sendmail-8.12.0.orig/sendmail/readcf.c sendmail-8.12.0/sendmail/readcf.c
  39 --- sendmail-8.12.0.orig/sendmail/readcf.c      Wed Sep  5 00:43:05 2001
  40 +++ sendmail-8.12.0/sendmail/readcf.c   Mon Sep 24 10:06:43 2001
  41 @@ -2039,6 +2039,10 @@
  42  # define O_SOFTBOUNCE  0xcf
  43         { "SoftBounce", O_SOFTBOUNCE,   OI_NONE },
  44  #endif /* _FFR_SOFT_BOUNCE */
  45 +#define O_DETECTTELNET 0xd0
  46 +       { "DetectTelnet",       O_DETECTTELNET,         OI_NONE },
  47 +#define O_EXITONTELNET 0xd1
  48 +       { "ExitOnTelnet",       O_EXITONTELNET,         OI_NONE },
  49         { NULL,                         '\0',           OI_NONE }
  50  };
  51
  52 @@ -3462,6 +3466,14 @@
  53                 break;
  54  #endif /* _FFR_SOFT_BOUNCE */
  55
  56 +         case O_DETECTTELNET:          /* detect telnet */
  57 +               DetectTelnet = atobool(val);
  58 +               break;
  59 +
  60 +         case O_EXITONTELNET:          /* exit if telnet detected */
  61 +               ExitOnTelnet = atobool(val);
  62 +               break;
  63 +
  64           default:
  65                 if (tTd(37, 1))
  66                 {
  67 diff -Nur sendmail-8.12.0.orig/sendmail/sendmail.h sendmail-8.12.0/sendmail/sendmail.h
  68 --- sendmail-8.12.0.orig/sendmail/sendmail.h    Wed Sep  5 00:43:05 2001
  69 +++ sendmail-8.12.0/sendmail/sendmail.h Mon Sep 24 10:01:52 2001
  70 @@ -2074,6 +2074,8 @@
  71  EXTERN bool    WorkAroundBrokenAAAA;   /* some nameservers return SERVFAIL on AAAA queries */
  72  EXTERN bool    UseErrorsTo;    /* use Errors-To: header (back compat) */
  73  EXTERN bool    UseNameServer;  /* using DNS -- interpret h_errno & MX RRs */
  74 +EXTERN bool    DetectTelnet;   /* force telnet detection on/off */
  75 +EXTERN bool    ExitOnTelnet;   /* exit if telnet detected */
  76  EXTERN char    InetMode;               /* default network for daemon mode */
  77  EXTERN char    OpMode;         /* operation mode, see below */
  78  EXTERN char    SpaceSub;       /* substitution for <lwsp> */
  79 diff -Nur sendmail-8.12.0.orig/sendmail/srvrsmtp.c sendmail-8.12.0/sendmail/srvrsmtp.c
  80 --- sendmail-8.12.0.orig/sendmail/srvrsmtp.c    Wed Sep  5 00:43:06 2001
  81 +++ sendmail-8.12.0/sendmail/srvrsmtp.c Mon Sep 24 10:09:38 2001
  82 @@ -12,6 +12,7 @@
  83   */
  84
  85  #include <sendmail.h>
  86 +#include <arpa/telnet.h>
  87  #if MILTER
  88  # include <libmilter/mfdef.h>
  89  #endif /* MILTER */
  90 @@ -369,6 +370,9 @@
  91         char *args[MAXSMTPARGS];
  92         char inp[MAXLINE];
  93         char cmdbuf[MAXLINE];
  94 +       char telnet_request[] = {IAC, DO, TELOPT_SGA, 0};
  95 +       char telnet_response[] = {IAC, WILL, TELOPT_SGA, 0};
  96 +       char *telnet_tmp;
  97  #if SASL
  98         sasl_conn_t *conn;
  99         volatile bool sasl_ok;
 100 @@ -666,12 +669,8 @@
 101         id = strchr(inp, ' ');
 102         if (id == NULL)
 103                 id = &inp[strlen(inp)];
 104 -       if (p == NULL)
 105 -               (void) sm_snprintf(cmdbuf, sizeof cmdbuf,
 106 -                        "%s %%.*s ESMTP%%s", greetcode);
 107 -       else
 108 -               (void) sm_snprintf(cmdbuf, sizeof cmdbuf,
 109 -                        "%s-%%.*s ESMTP%%s", greetcode);
 110 +       sm_snprintf(cmdbuf, sizeof cmdbuf, "%s%c%%.*s ESMTP%%s%s", greetcode,
 111 +               (p == NULL) ? ' ' : '-', DetectTelnet ? telnet_request : "");
 112         message(cmdbuf, (int) (id - inp), inp, id);
 113
 114         /* output remaining lines */
 115 @@ -764,6 +763,20 @@
 116                         goto doquit;
 117                 }
 118
 119 +               if (DetectTelnet && strlen(inp) >= 3)
 120 +                       for (telnet_tmp = inp; *(telnet_tmp+2); telnet_tmp++)
 121 +                               if (!strncmp(telnet_tmp, telnet_response, 3))
 122 +                               {
 123 +                                       sm_syslog(LOG_NOTICE, e->e_id,
 124 +                                         "telnet detected from %.100s (%.100s)",
 125 +                                         CurSmtpClient, anynet_ntoa(&RealHostAddr));
 126 +                                       if (ExitOnTelnet)
 127 +                                       {
 128 +                                               message("571 Unauthorized usage prohibited");
 129 +                                               goto doquit;
 130 +                                       }
 131 +                               }
 132 +
 133  #if _FFR_ADAPTIVE_EOL
 134                 if (first)
 135                 {