xref: /original-bsd/usr.sbin/sendmail/src/READ_ME (revision 11a85fef)
1# Copyright (c) 1983 Eric P. Allman
2# Copyright (c) 1988 The Regents of the University of California.
3# All rights reserved.
4#
5# %sccs.include.redist.sh%
6#
7#	@(#)READ_ME	8.25 (Berkeley) 09/22/93
8#
9
10This directory contains the source files for sendmail.
11
12For detailed instructions, please read the document ../doc/op.me:
13
14	eqn ../doc/op.me | pic | ditroff -me
15
16The Makefile is for the new (4.4BSD) Berkeley make, available from
17ftp.uu.net in the directory /systems/unix/bsd-sources/usr.bin/make.
18(Paul Southworth <pauls@umich.edu> published a description of porting
19this make in comp.unix.bsd.)  This Makefile has assumptions about the
204.4 file system layout built in.
21
22There is also a Makefile.dist which is much less clever, but works on
23the old traditional make.  You can use this using:
24
25	make -f Makefile.dist
26
27There are a bunch of other Makefiles for other systems -- these are
28the ones that I use, they have "Berkeley quirks" in them, and I don't
29guarantee that they will work unmodified in your environment.  However,
30they are all designed for the old make and can be used to help you get
31started.  They have names like "Makefile.HPUX".  Many of them include
32-I/usr/sww/include/db and -L/usr/sww/lib -- this is Berkeley's
33location for the new database libraries, described below.
34
35There is also a shell script (makesendmail) that tries to be clever
36about using object subdirectories.  It's pretty straightforward, and
37may help if you share a source tree among different architectures.
38
39
40+----------------------+
41| DATABASE DEFINITIONS |
42+----------------------+
43
44There are several database formats that can be used for the alias files
45and for general maps.  When used for alias files they interact in an
46attempt to be back compatible.
47
48The three options are NEWDB (the new Berkeley DB package), NDBM (the
49older DBM implementation -- the very old V7 implementation is no
50longer supported), and NIS (Network Information Services).  Used alone
51these just include the support they indicate.  [If you are using NEWDB,
52get the latest version from FTP.CS.Berkeley.EDU in /ucb/4bsd.  DO NOT
53use the version from the Net2 distribution!]
54
55If NEWDB and NDBM are defined (but not NIS), then sendmail will read
56NDBM format alias files, but the next time a newaliases is run the
57format will be converted to NEWDB; that format will be used forever
58more.  This is intended as a transition feature.  [Note however that
59the NEWDB library also catches and maps NDBM calls; you will have to
60back out this feature to get this to work.  See ``Quirks'' section
61below for details.]
62
63If all three are defined, sendmail operates as described above, and also
64looks for the file /var/yp/Makefile.  If it exists, newaliases will
65build BOTH the NEWDB and NDBM format alias files.  However, it will
66only use the NEWDB file; the NDBM format file is used only by the
67NIS subsystem.
68
69If NDBM and NIS are defined (regardless of the definition of NEWDB
70or the existance of /var/yp/Makefile), sendmail adds the special
71tokens "YP_LAST_MODIFIED" and "YP_MASTER_NAME", both of which are
72required if the NDBM file is to be used as an NIS map.
73
74All of -DNEWDB, -DNDBM, and -DNIS are normally defined in the DBMDEF
75line in the Makefile.
76
77
78+---------------+
79| COMPILE FLAGS |
80+---------------+
81
82Whereever possible, I try to make sendmail pull in the correct
83compilation options needed to compile on various environments based on
84automatically defined symbols.  Some machines don't seem to have useful
85symbols availble, requiring the following compilation flags in the
86Makefile:
87
88SOLARIS		Define this if you are running Solaris 2.0 or higher.
89NeXT		Define this if you are on a NeXT box.  (This one may
90		be pre-defined for you.)  There are other hacks you
91		have to make -- see below.
92_AIX3		Define this if you are IBM AIX 3.x.
93RISCOS		Define this if you are running RISC/os from MIPS.
94_SCO_unix_	Define this if you are on SCO UNIX.
95
96If you are a system that sendmail has already been ported to, you
97probably won't have to touch these.  But if you are porting, you may
98have to tweak the following compilation flags in conf.h in order to
99get it to compile and link properly:
100
101SYSTEM5		Adjust for System V.
102SYS5SIGNALS	Use System V signal semantics -- the signal handler
103		is automatically dropped when the signal is caught.
104		If this is not set, use POSIX/BSD semantics, where the
105		signal handler stays in force until an exec or an
106		explicit delete.  Implied by SYSTEM5.
107HASFLOCK	Set this if you prefer to use the flock(2) system call
108		rather than using fcntl-based locking.  Fcntl locking
109		has some semantic gotchas, but many vendor systems
110		also interface it to lockd(8) to do NFS-style locking.
111		For this reason, this should not be set unless you
112		don't have an alternative.
113HASUNAME	Set if you have the "uname" system call.  Implied by
114		SYSTEM5.
115HASUNSETENV	Define this if your system library has the "unsetenv"
116		subroutine.
117HASSTATFS	Define this if you have the statfs(2) system call.  It's
118		not a disaster to get this wrong -- but you do lose the
119		queue free space code.
120HASUSTAT	Define this if you have the ustat(2) system call.  It's
121		not a disaster to get this wrong -- but you do lose the
122		queue free space code.
123HASSETSID	Define this if you have the setsid(2) system call.  This
124		is implied if your system appears to be POSIX compliant.
125HASINITGROUPS	Define this if you have the initgroups(3) routine.
126HASSETVBUF	Define this if you have the setvbuf(3) library call.
127		If you don't, setlinebuf will be used instead.  This
128		defaults on if your compiler defines __STDC__.
129HASSETREUID	Define this if you have setreuid(2) ***AND*** root can
130		use setreuid to change to an arbitrary user.  This second
131		condition is not satisfied on AIX 3.x.  You may find that
132		your system has setresuid(2), (for example, on HP-UX) in
133		which case you will also have to #define setreuid(r, e)
134		to be the appropriate call.  Some systems (such as Solaris)
135		have a compatibility routine that doesn't work properly.
136		The important thing is that you have a call that will set
137		the effective uid independently of the real or saved uid.
138		Setting this improves the security somewhat, since
139		sendmail doesn't have to read .forward and :include: files
140		as root.
141GIDSET_T	The type of entries in a gidset passed as the second
142		argument to getgroups(2).  Historically this has been an
143		int, so this is the default, but some systems (such as
144		IRIX) pass it as a gid_t, which is an unsigned short.
145		This will make a difference, so it is important to get
146		this right!  However, it is only an issue if you have
147		group sets.
148SLEEP_T		The type returned by the system sleep() function.
149		Defaults to "unsigned int".  Don't worry about this
150		if you don't have compilation problems.
151ARBPTR_T	The type of an arbitrary pointer -- defaults to "void *".
152		If you are an very old compiler you may need to define
153		this to be "char *".
154LA_TYPE		The type of load average your kernel supports.  These
155		can be LA_SUBR (4) if you have the getloadavg(3) routine,
156		LA_MACH (5) to use MACH-style load averages (calls
157		processor_set_info()), LA_FLOAT (3) if you read kmem and
158		interpret the value as a floating point number, LA_INT (2)
159		to interpret as a long integer, or LA_SHORT (6) to
160		interpret as a short integer.  These last three have
161		several other parameters that they try to divine: the
162		name of your kernel, the name of the variable in the
163		kernel to examine, the number of bits of precision in
164		a fixed point load average, and so forth.  In desparation,
165		use LA_ZERO (1) -- it always returns the load average as
166		"zero" (and does so on all architectures).  The actual
167		code is in conf.c -- it can be tweaked if you are brave.
168ERRLIST_PREDEFINED
169		If set, assumes that some header file defines sys_errlist.
170		This may be needed if you get type conflicts on this
171		variable -- otherwise don't worry about it.
172WAITUNION	The wait(2) routine takes a "union wait" argument instead
173		of an integer argument.  This is for compatibility with
174		old versions of BSD.
175
176
177+-----------------------+
178| COMPILE-TIME FEATURES |
179+-----------------------+
180
181There are a bunch of features that you can decide to compile in, such
182as selecting various database packages and special protocol support.
183Several are assumed based on other compilation flags -- if you want to
184"un-assume" something, you probably need to edit conf.h.  Compilation
185flags that add support for special features include:
186
187NDBM		Include support for "new" DBM library for aliases and maps.
188		Normally defined in the Makefile.
189NEWDB		Include support for Berkeley "db" package (hash & btree)
190		for aliases and maps.  Normally defined in the Makefile.
191NIS		Define this to get NIS (YP) support for aliases and maps.
192		Normally defined in the Makefile.
193USERDB		Include support for the User Information Database.  Implied
194		by NEWDB in conf.h.
195IDENTPROTO	Define this to get IDENT (RFC 1413) protocol support.
196		This is assumed unless you are running on Ultrix or
197		HP-UX, both of which have a problem in the UDP
198		implementation.
199MIME		Include support for MIME-encapsulated error messages.
200LOG		Set this to get syslog(3) support.  Defined by default
201		in conf.h.  You want this if at all possible.
202NETINET		Set this to get TCP/IP support.  Defined by default
203		in conf.h.  You probably want this.
204NETISO		Define this to get ISO networking support.
205SMTP		Define this to get the SMTP code.  Implied by NETINET
206		or NETISO.
207NAMED_BIND	Define this to get DNS (name daemon) support, including
208		MX support.  The specs you must use this if you run
209		SMTP.  Defined by default in conf.h.
210QUEUE		Define this to get queueing code.  Implied by NETINET
211		or NETISO; required by SMTP.  This gives you other good
212		stuff -- it should be on.
213DAEMON		Define this to get general network support.  Implied by
214		NETINET or NETISO.  Defined by default in conf.h.  You
215		almost certainly want it on.
216MATCHGECOS	Permit fuzzy matching of user names against the full
217		name (GECOS) field in the /etc/passwd file.  This should
218		probably be on, since you can disable it from the config
219		file if you want to.  Defined by default in conf.h.
220SETPROCTITLE	Try to set the string printed by "ps" to something
221		informative about what sendmail is doing.  Defined by
222		default in conf.h.
223
224
225+-------------------------------------+
226| OPERATING SYSTEM AND COMPILE QUIRKS |
227+-------------------------------------+
228
229SunOS 4.x (Solaris 1.x)
230	You may have to use -lresolv on SunOS.  However, beware that
231	this links in a new version of gethostbyname that does not
232	understand NIS, so you must have all of your hosts in DNS.
233
234	There is substantial disagreement about whether you can make
235	this work with resolv+, which allows you to specify a search-path
236	of services.  Some people report that it works fine, others
237	claim it doesn't work at all (including causing sendmail to
238	drop core when it tries to do multiple resolv+ lookups for a
239	single job).  I haven't tried resolv+, as we use DNS exclusively.
240
241	Should you want to try resolv+, it is on ftp.uu.net in
242	/networking/ip/dns.
243
244Solaris 2.x (SunOS 5.x)
245	To compile for Solaris, be sure you use -DSOLARIS.
246
247	From a correspondent:
248
249	   For solaris 2.2, I have
250
251		hosts:      files dns
252
253	   in /etc/nsswitch.conf and /etc/hosts has to have the fully
254	   qualified host name. I think "files" has to be before "dns"
255	   in /etc/nsswitch.conf during bootup.
256
257	To the best of my knowledge, Solaris does not have the
258	gethostbyname problem described above.
259
260	The Solaris "syslog" function is apparently limited to something
261	about 90 characters because of a kernel limitation.  If you have
262	source code, you can probably up this number.  Bill Wisner
263	<wisner@well.sf.ca.us> was able to get an unofficial, unsupported
264	patch.
265
266OSF/1
267	If you are compiling on OSF/1 (DEC Alpha), you must use -lmld.
268
269NeXT
270	If you are compiling on NeXT, you will have to create an empty
271	file "unistd.h" and create a file "dirent.h" containing:
272
273		#include <sys/dir.h>
274		#define dirent	direct
275
276	(The Makefile.NeXT should try to do both of these for you.)
277
278	Apparently, there is a bug in getservbyname on Nextstep 3.0
279	that causes it to fail under some circumstances with the
280	message "SYSERR: service "smtp" unknown" logged.  You should
281	be able to work around this by including the line:
282
283		OPort=25
284
285	in your .cf file.
286
287	You may have to use -DNeXT.
288
289BSDI (BSD/386)
290	I have reports that the "m4" from BSDI won't handle the config
291	files properly.  I haven't had a chance to test this myself.
292
2934.3BSD
294	If you are running a "virgin" version of 4.3BSD, you'll have
295	a very old resolver and be missing some header files.  The
296	header files are simple -- create empty versions and everything
297	will work fine.  For the resolver you should really port a new
298	version (4.8.3 or later) of the resolver; 4.9 is available on
299	gatekeeper.DEC.COM in pub/BSD/bind/4.9.  If you are really
300	determined to continue to use your old, buggy version (or as
301	a shortcut to get sendmail working -- I'm sure you have the
302	best intentions to port a modern version of BIND), you can
303	copy ../contrib/oldbind.compat.c into src and add
304	oldbind.compat.o to OBJADD in the Makefile.
305
306Linux
307	From: Karl London <karl@borg.demon.co.uk>
308	Subject: Little bit to add to a readme for Linux for 8.6
309	Date: Fri, 10 Sep 1993 20:16:05 +0100 (BST)
310
311	Below is a copy of a section of the /usr/include/unistd.h from
312	linux libc-4.4.1 which needs changing because of a bug in the
313	header files. Should be fixed for future releases..
314
315	Karl
316
317	The #if 0 and #endif are new!!
318
319	-------
320
321	   If OPTS begins with `--', then non-option arguments
322	   are treated as arguments to the option '\0'.
323	   This behavior is specific to the GNU `getopt'.  */
324	#if 0
325	extern int getopt __P ((int __argc, char *__const * __argv,
326				__const char *__opts));
327	#endif
328	extern int opterr;
329	extern int optind;
330
331Both NEWDB and NDBM
332	If you use both -DNDBM and -DNEWDB, you must delete the module
333	ndbm.o from libdb.a and delete the file "ndbm.h" from the files
334	that get installed (that is, use the OLD ndbm.h, not the new
335	ndbm.h).  This compatibility module maps ndbm calls into DB
336	calls, and breaks things rather badly.
337
338GNU getopt
339	I'm told that GNU getopt has a problem in that it gets confused
340	by the double call.  Use the version in conf.c instead.
341
342
343+-----------------------------+
344| DESCRIPTION OF SOURCE FILES |
345+-----------------------------+
346
347The following list describes the files in this directory:
348
349Makefile	The makefile used here; this version only works with
350		the new Berkeley make.
351Makefile.dist	A trimmed down version of the makefile that works with
352		the old make.
353READ_ME		This file.
354TRACEFLAGS	My own personal list of the trace flags -- not guaranteed
355		to be particularly up to date.
356alias.c		Does name aliasing in all forms.
357arpadate.c	A subroutine which creates ARPANET standard dates.
358clock.c		Routines to implement real-time oriented functions
359		in sendmail -- e.g., timeouts.
360collect.c	The routine that actually reads the mail into a temp
361		file.  It also does a certain amount of parsing of
362		the header, etc.
363conf.c		The configuration file.  This contains information
364		that is presumed to be quite static and non-
365		controversial, or code compiled in for efficiency
366		reasons.  Most of the configuration is in sendmail.cf.
367conf.h		Configuration that must be known everywhere.
368convtime.c	A routine to sanely process times.
369daemon.c	Routines to implement daemon mode.  This version is
370		specifically for Berkeley 4.1 IPC.
371deliver.c	Routines to deliver mail.
372domain.c	Routines that interface with DNS (the Domain Name
373		System).
374err.c		Routines to print error messages.
375envelope.c	Routines to manipulate the envelope structure.
376headers.c	Routines to process message headers.
377macro.c		The macro expander.  This is used internally to
378		insert information from the configuration file.
379main.c		The main routine to sendmail.  This file also
380		contains some miscellaneous routines.
381map.c		Support for database maps.
382mci.c		Routines that handle mail connection information caching.
383parseaddr.c	The routines which do address parsing.
384queue.c		Routines to implement message queueing.
385readcf.c	The routine that reads the configuration file and
386		translates it to internal form.
387recipient.c	Routines that manipulate the recipient list.
388savemail.c	Routines which save the letter on processing errors.
389sendmail.h	Main header file for sendmail.
390srvrsmtp.c	Routines to implement server SMTP.
391stab.c		Routines to manage the symbol table.
392stats.c		Routines to collect and post the statistics.
393sysexits.c	List of error messages associated with error codes
394		in sysexits.h.
395trace.c		The trace package.  These routines allow setting and
396		testing of trace flags with a high granularity.
397udb.c		The user database interface module.
398usersmtp.c	Routines to implement user SMTP.
399util.c		Some general purpose routines used by sendmail.
400version.c	The version number and information about this
401		version of sendmail.  Theoretically, this gets
402		modified on every change.
403
404Eric Allman
405
406(Version 8.25, last update 09/22/93 10:32:22)
407