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Diffstat (limited to 'contrib/sendmail/libmilter/README')
| -rw-r--r-- | contrib/sendmail/libmilter/README | 85 |
1 files changed, 58 insertions, 27 deletions
diff --git a/contrib/sendmail/libmilter/README b/contrib/sendmail/libmilter/README index 3eae861..f38f68a 100644 --- a/contrib/sendmail/libmilter/README +++ b/contrib/sendmail/libmilter/README @@ -9,17 +9,27 @@ through reference to a sample filter which is attached at the end of this file. It is necessary to first build libmilter.a, which can be done by issuing the './Build' command in SRCDIR/libmilter . -NOTE: Both libmilter and the callouts in sendmail are marked as an FFR (For -Future Release). If you intend to use them in 8.11.X, you must compiled -both libmilter and sendmail with -D_FFR_MILTER defined. You can do this by -adding the following to your devtools/Site/site.config.m4 file: +NOTE: If you intend to use filters in sendmail, you must compile sendmail +with -DMILTER defined. You can do this by adding the following to +your devtools/Site/site.config.m4 file: - dnl Milter - APPENDDEF(`conf_sendmail_ENVDEF', `-D_FFR_MILTER=1') - APPENDDEF(`conf_libmilter_ENVDEF', `-D_FFR_MILTER=1') + APPENDDEF(`conf_sendmail_ENVDEF', `-DMILTER') + ++----------------+ +| SECURITY HINTS | ++----------------+ + +Note: we strongly recommend not to run any milter as root. Libmilter +does not need root access to communicate with sendmail. It is a +good security practice to run a program only with root privileges +if really necessary. A milter should probably check first whether +it runs as root and refuse to start in that case. There is a +compile time option _FFR_MILTER_ROOT_UNSAFE which keeps libmilter +from unlinking a socket when running as root. It is recommended +to turn on this option: + + APPENDDEF(`conf_libmilter_ENVDEF', `-D_FFR_MILTER_ROOT_UNSAFE ') -You will also need to define _FFR_MILTER when building your .cf file using -m4. +-------------------+ | BUILDING A FILTER | @@ -29,14 +39,14 @@ The following command presumes that the sample code from the end of this README is saved to a file named 'sample.c' and built in the local platform- specific build subdirectory (SRCDIR/obj.*/libmilter). - cc -I../../sendmail -I../../include -o sample sample.c libmilter.a ../libsmutil/libsmutil.a -pthread + cc -I../../sendmail -I../../include -o sample sample.c libmilter.a ../libsm/libsm.a -pthread It is recommended that you build your filters in a location outside of the sendmail source tree. Modify the compiler include references (-I) and the library locations accordingly. Also, some operating systems may require additional libraries. For example, SunOS 5.X requires '-lresolv --lsocket -lnsl'. Depending on your OS you may need a library instead -of the option -pthread, e.g., -lpthread. +-lsocket -lnsl'. Depending on your operating system you may need a library +instead of the option -pthread, e.g., -lpthread. Filters must be thread-safe! Many operating systems now provide support for POSIX threads in the standard C libraries. The compiler flag to link with @@ -77,13 +87,13 @@ IPv4 socket on port 3333 of localhost. The current flags (F=) are: T Temporary fail connection if filter unavailable If neither F=R nor F=T is specified, the message is passed through sendmail -as if the filter were not present. +in case of filter errors as if the failing filters were not present. Finally, you can override the default timeouts used by sendmail when talking to the filters using the T= equate. There are four fields inside of the T= equate: -Letter Meaning +Letter Meaning C Timeout for connecting to a filter (if 0, use system timeout) S Timeout for sending information from the MTA to a filter R Timeout for reading reply from the filter @@ -94,7 +104,7 @@ Note the separator between each is a ';' as a ',' already separates equates and therefore can't separate timeouts. The default values (if not set in the config) are: -T=C:0m;S:10s;R:10s;E:5m +T=C:5m;S:10s;R:10s;E:5m where 's' is seconds and 'm' is minutes. @@ -182,6 +192,30 @@ the logging level of sendmail can be raised with the LogLevel option. See the sendmail(8) manual page for more information. ++--------------+ +| REQUIREMENTS | ++--------------+ + +libmilter requires pthread support in the operating system. Moreover, it +requires that the library functions it uses are thread safe; which is true +for the operating systems libmilter has been developed and tested on. On +some operating systems this requires special compile time options (e.g., +not just -pthread). libmilter is currently known to work on (modulo problems +in the pthread support of some specific versions): + +FreeBSD 3.x, 4.x +SunOS 5.x (x >= 5) +AIX 4.3.x +HP UX 11.x +Linux (recent versions/distributions) + +libmilter is currently not supported on: + +IRIX 6.x +Ultrix + +Feedback about problems (and possible fixes) is welcome. + +--------------------------+ | SOURCE FOR SAMPLE FILTER | +--------------------------+ @@ -201,14 +235,11 @@ below to verify the functions are thread safe. #include "libmilter/mfapi.h" +#ifndef true typedef int bool; - -#ifndef FALSE -# define FALSE 0 -#endif /* ! FALSE*/ -#ifndef TRUE -# define TRUE 1 -#endif /* ! TRUE*/ +# define false 0 +# define true 1 +#endif /* ! true */ struct mlfiPriv { @@ -295,7 +326,7 @@ mlfi_body(ctx, bodyp, bodylen) if (fwrite(bodyp, bodylen, 1, MLFIPRIV->mlfi_fp) <= 0) { /* write failed */ - (void) mlfi_cleanup(ctx, FALSE); + (void) mlfi_cleanup(ctx, false); return SMFIS_TEMPFAIL; } @@ -307,7 +338,7 @@ sfsistat mlfi_eom(ctx) SMFICTX *ctx; { - return mlfi_cleanup(ctx, TRUE); + return mlfi_cleanup(ctx, true); } sfsistat @@ -321,7 +352,7 @@ sfsistat mlfi_abort(ctx) SMFICTX *ctx; { - return mlfi_cleanup(ctx, FALSE); + return mlfi_cleanup(ctx, false); } sfsistat @@ -349,7 +380,7 @@ mlfi_cleanup(ctx, ok) { /* add a header to the message announcing our presence */ if (gethostname(host, sizeof host) < 0) - strlcpy(host, "localhost", sizeof host); + snprintf(host, sizeof host, "localhost"); p = strrchr(priv->mlfi_fname, '/'); if (p == NULL) p = priv->mlfi_fname; @@ -426,4 +457,4 @@ main(argc, argv) /* eof */ -$Revision: 8.9.2.1.2.19 $, Last updated $Date: 2001/06/28 22:25:14 $ +$Revision: 8.35 $, Last updated $Date: 2002/01/07 21:29:20 $ |
