From a81c28f4a2ee69469c5e9f5d65389a89c6070ed4 Mon Sep 17 00:00:00 2001 From: Dan Harkless Date: Fri, 3 Mar 2000 07:24:41 +0000 Subject: [PATCH] Added a new "boolean" type to mh.h and TRUE and FALSE constants. Added a note to DIFFERENCES stating that it's out-of-date (Richard was the last one to update it) and that we should consider only documenting incompatibilities with MH there. Implemented (and documented) a third kind of username masquerading: "plussed user" masquerading. This one was suggested by Neil Rickert . It's based on sendmail's "plussed user" feature, where mail sent to + will be delivered to . When it's enabled, it's controlled by the $USERPLUS environment variable. How is it enabled? Well, that leads me to: Renamed the "mmailid:" setting in mts.conf to "masquerade:", and changed it so that rather than being a boolean, it can be set to any combination of the three values "draft_from", "mmailid", and "plussed_user". Thus it is now possible to enable the three types of masquerading individually. Fixed a bug with "mmailid" masquerading (dating back to MH?) where if it was turned on, ','s would no longer be considered GECOS field delimiters. --- ChangeLog | 26 ++++++++++++ DIFFERENCES | 3 ++ INSTALL | 67 +++++++++---------------------- etc/mts.conf.in | 27 +++++++------ h/mh.h | 8 ++++ man/mh-tailor.man | 48 +++++++++++++++------- man/post.man | 55 +++++++++++++++----------- uip/post.c | 56 ++++++++++++++------------ zotnet/mts/mts.c | 114 ++++++++++++++++++++++++++++++++++++++++------------- 9 files changed, 252 insertions(+), 152 deletions(-) diff --git a/ChangeLog b/ChangeLog index d96f7c1..bbe8092 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,29 @@ +Thu Mar 02 23:04:30 2000 Dan Harkless + + * Added a new "boolean" type to mh.h and TRUE and FALSE constants. + + * Added a note to DIFFERENCES stating that it's out-of-date + (Richard was the last one to update it) and that we should + consider only documenting incompatibilities with MH there. + + * Implemented (and documented) a third kind of username + masquerading: "plussed user" masquerading. This one was suggested + by Neil Rickert . It's based on sendmail's + "plussed user" feature, where mail sent to + will be + delivered to . When it's enabled, it's controlled by the + $USERPLUS environment variable. How is it enabled? Well, that + leads me to: + + * Renamed the "mmailid:" setting in mts.conf to "masquerade:", and + changed it so that rather than being a boolean, it can be set to + any combination of the three values "draft_from", "mmailid", and + "plussed_user". Thus it is now possible to enable the three types + of masquerading individually. + + * Fixed a bug with "mmailid" masquerading (dating back to MH?) + where if it was turned on, ','s would no longer be considered + GECOS field delimiters. + Wed Mar 01 23:30:50 2000 Dan Harkless * Changed the GECOS-field '&' translation behavior to be diff --git a/DIFFERENCES b/DIFFERENCES index 1a24037..b664639 100644 --- a/DIFFERENCES +++ b/DIFFERENCES @@ -1,3 +1,6 @@ +[NOTE: This file is out-of-date. Updating it every time new features are added + to nmh forevermore is a pain. Perhaps we should limit it to + documentation of _incompatibilities_ with MH (which should be rare).] The following are the differences between nmh and MH-6.8.3. UCI has since released MH-6.8.4. Most of the new features it adds have diff --git a/INSTALL b/INSTALL index 63dcbbe..7eae1db 100644 --- a/INSTALL +++ b/INSTALL @@ -45,62 +45,33 @@ need an ANSI C compiler such as gcc. injecting the message to a mail transfer agent (such as sendmail) on the local machine via SMTP. - If you have enabled POP support and you want this to be the - default method of accessing new mail, you will need to change - the values of the variables "servers", "pophost", "localname", - and possibly "mmailid". - - a) "servers" defines the server to which you send outgoing SMTP - traffic. - - b) "pophost" defines the server that runs the POP daemon, and to - which `inc' and `msgchk' will query for new mail. - - c) "localname" defines the hostname that nmh considers local. - If not set, then nmh queries your OS for this value. You may - want to change this if you wish your e-mail to appear as if it - originated on the POP server. - - d) "mmailid" allows two different types of email address masquerading - when it's set to be non-zero. The first type is GECOS-based - masquerading. nmh will check if the user's pw_gecos field in the passwd - is of the form: - - Full Name - - If it is, the internal nmh routines that find the username and full - name of that user will return "fakeusername" and "Full Name" - respectively. This is useful if you want the messages you send to - always appear to come from the name of an MTA alias rather than your - actual account name. For instance, many organizations set up - "First.Last" sendmail aliases for all users. If this is the case, - the GECOS field for each user should look like: - - First [Middle] Last - - The other type of masquerading that mmailid turns on is envelope - "From:" masquerading based on draft contents. When a user explicitly - specifies a "From:" header in a message, nmh uses it rather than - constructing its own. However, the SMTP envelope "From:" and the - "Sender:" header are set to the user's real address. Turning on - mmailid prevents this latter behavior. This is useful when the user - wants to pretend to be sending mail "directly" from a remote POP3 - account, or when remote mail robots incorrectly use the envelope - "From:" in preference to the body "From:" (or refuse to take action - when the two don't match). + If, instead, all your mail sending and receiving occurs on a + remote POP/SMTP server, you will need to look at the values of the + variables "localname", "pophost", and "servers": + + a) "localname" defines the hostname that nmh considers local. + If not set, then nmh queries your OS for this value. You will + want to change this if you wish your e-mail to appear as if it + originated on the POP server. + + b) "pophost" defines the server that runs the POP daemon, and to + which `inc' and `msgchk' will always query for new mail. + + c) "servers" defines the server to which you send outgoing SMTP + traffic. If you compile with POP support, but don't want to use it exclusively, you can use the `-host' and `-user' options to `inc' and `msgchk' - rather than hardcoding values in `mts.conf'. + rather than hardcoding pophost in `mts.conf'. Check the `mh-tailor' man page for a list of all the available options - for this file. + for this file ("masquerade" may be of particular interest). 6) If you have enabled POP support, make sure that `pop3' (or more precisely the value of the define POPSERVICE in config.h) is defined in the /etc/services file (or its NIS/NIS+ equivalent) on the client machine. It should be something equivalent to "110/tcp". This might - have already been done when the pop daemon was installed. + have already been done when the POP daemon was installed. 7) Edit the file `mhn.defaults' (installed in the nmh `etc' directory). This file contains the default profile entries for the nmh command @@ -111,8 +82,8 @@ need an ANSI C compiler such as gcc. want to re-run this script later if you install new programs to display content. An example of this is: - cd support/general - ./mhn.defaults.sh /usr/local/bin:/usr/X11/bin:/usr/ucb > mhn.defaults + % cd support/general + % ./mhn.defaults.sh /usr/local/bin:/usr/X11/bin:/usr/ucb > mhn.defaults and then move `mhn.defaults' into the nmh `etc' directory. diff --git a/etc/mts.conf.in b/etc/mts.conf.in index b8a61b8..6f1af4f 100644 --- a/etc/mts.conf.in +++ b/etc/mts.conf.in @@ -5,6 +5,18 @@ # all the available options for this file. # +# The exceptions file for /etc/hosts used by +# `post' to try to find official names. +hostable: %etcdir%/hosts + +# Name that nmh considers `local'. If not set, nmh will +# query the system for this value (gethostname, etc...). +#localname: foo.bar.com + +# Uncomment the following line to allow username masquerading. Any or all of +# the three types of masquerading may be used (see mh-tailor(5) for details). +#masquerade: draft_from mmailid plussed_user + # Default location of mail drops. If this option is # set, but empty, the user's home directory is used. mmdfldir: %mailspool% @@ -13,19 +25,8 @@ mmdfldir: %mailspool% # are kept. If this is empty, the user's login name is used. mmdflfil: -# The exceptions file for /etc/hosts used by -# `post' to try to find official names. -hostable: %etcdir%/hosts +# Hardcoded POP server name (prevents inc'ing from local mail spool). +#pophost: localhost # List of smtp servers to try if using smtp support servers: localhost - -# Name of POP server -# pophost: localhost - -# Name that nmh considers `local'. If not set, nmh will -# query the system for this value (gethostname, etc...). -# localname: foo.bar.com - -# Uncomment this to allow the two types of username masquerading. -# mmailid: 1 diff --git a/h/mh.h b/h/mh.h index a59b0a0..81a6021 100644 --- a/h/mh.h +++ b/h/mh.h @@ -21,6 +21,14 @@ #define DMAXFOLDER 4 /* typical number of digits */ #define MAXFOLDER 1000 /* message increment */ +#ifndef FALSE +#define FALSE 0 +#endif +#ifndef TRUE +#define TRUE 1 +#endif +typedef unsigned char boolean; /* not int so we can pack in a structure */ + /* * user context/profile structure */ diff --git a/man/mh-tailor.man b/man/mh-tailor.man index ea95045..ff767b0 100644 --- a/man/mh-tailor.man +++ b/man/mh-tailor.man @@ -99,12 +99,17 @@ mmdelim2: \\001\\001\\001\\001\\n The end-of-message delimiter for maildrops. .ti -.5i -mmailid: 0 +masquerade: .br -If this is non-zero, two different types of email address masquerading are -allowed ("mmailid" = "masquerade mail ID"). The first type is GECOS-based -masquerading. \fInmh\fR will check if the user's pw_gecos field in the passwd -file is of the form: +This directive controls three different types of email address masquerading. +The three possible values, which may be specified in any combination on the +line, are "draft_from", "mmailid", and "plussed_user". + +"mmailid" was the only type of masquerading in the original MH package, and +apparently stands for "masquerade mail identification". This type of +masquerading keys off of the GECOS field of the passwd file. When enabled, +\fInmh\fR will check if the user's pw_gecos field in the passwd file is of the +form: .ti +.5i Full Name @@ -119,15 +124,28 @@ the case, the GECOS field for each user should look like: .ti +.5i First [Middle] Last -The other type of masquerading that mmailid turns on is envelope "From:" -masquerading based on draft contents. When a user explicitly specifies a -"From:" header in a message, \fInmh\fR uses it rather than constructing its own. -However, the SMTP envelope "From:" and the "Sender:" header are set to the -user's real address. Turning on mmailid prevents this latter behavior. This is -useful when the user wants to pretend to be sending mail "directly" from a -remote POP3 account, or when remote mail robots incorrectly use the envelope -"From:" in preference to the body "From:" (or refuse to take action when the two -don't match). +"plussed_user", when specified on the "masquerade:" line, allows a second type +of username masquerading. If the user sets the \fB$USERPLUS\fR environment +variable, its value will be tacked onto the actual login name, following a '+' +sign. For instance, if I am dan@company.com, and I set \fB$USERPLUS\fR to +"www", my mail will appear to come from "dan+www@company.com". This feature is +meant to interact with MTA features like the one in sendmail that automatically +delivers all mail sent to \fIuser\fR+\fIstring\fR to \fIuser\fR. One can use +different email addresses in different situations (to aid in automatic mail +filtering or in determining where spammers got your address) while only actually +having a single account. + +"draft_from" controls the most powerful type of address masquerading. Normally, +when a user explicitly specifies a "From:" header in a draft, \fInmh\fR uses it +rather than constructing its own. However, to discourage email forgery, the +SMTP envelope "From:" and a "Sender:" header are set to the user's real address. +When "draft_from" is turned on, though, the envelope "From:" will use the +address specified in the draft, and there will be no "Sender:" header. This is +useful when a user wants to pretend to be sending mail "directly" from a remote +POP3 account, or when remote mail robots incorrectly use the envelope "From:" in +preference to the body "From:" (or refuse to take action when the two don't +match). Note that your MTA may still reveal the user's real identity (e.g. +sendmail's "X-Authentication-Warning:" header). .ti -.5i maildelivery: %libdir%/maildelivery @@ -290,7 +308,7 @@ your site, and set the appropriate values. .Pr None .Sa -mh\-mts(8) +mh\-mts(8), post(8) .De As listed above .Co diff --git a/man/post.man b/man/post.man index d5b9e4e..c344043 100644 --- a/man/post.man +++ b/man/post.man @@ -74,36 +74,45 @@ transport system's handling of the message (e.g., local and \*(lqfast\*(rq delivery). Under normal circumstances, \fIpost\fR constructs the "From:" line of the -message from the user's UNIX username, the full name from the GECOS field of the -passwd file, and the fully-qualified name of the local machine (e.g. `From: "Dan -Harkless" '). However, there are three ways to -override these values. Note that they apply equally to "Resent-From:" lines in -messages sent with \fIdist\fR. +message from the user's login name, the full name from the GECOS field of the +passwd file, and the fully-qualified name of the local machine (or the value of +"localname" in mts.conf, if set). An example is "From: Dan Harkless +". There are four ways to override these values, +however. Note that they apply equally to "Resent-From:" lines in messages sent +with \fIdist\fR. -The first way is GECOS-based username masquerading. If "mmailid" in the -mts.conf file has been set to non-zero, this processing is activated. If a -user's GECOS field in the passwd file is of the form "Full Name " then -"fakename" will be used in place of the real username. For instance, a GECOS -field of "Dan Harkless " would result in `From: "Dan Harkless" -'. Naturally if you were doing something like +The first way is GECOS-based username masquerading. If the "masquerade:" line +in mts.conf contains "mmailid", this processing is activated. If a user's GECOS +field in the passwd file is of the form "Full Name " then "fakename" +will be used in place of the real username. For instance, a GECOS field of "Dan +Harkless " would result in "From: Dan Harkless +". Naturally if you were doing something like this you'd want to set up an MTA alias (e.g. in /etc/aliases) from, for instance, "Dan.Harkless" to "dan". The second way to override default construction of "From:" is to set the \fB$SIGNATURE\fR environment variable. This variable overrides the full name -from the GECOS field, even if GECOS-based masquerading is being done. +from the GECOS field, even if GECOS-based masquerading is being done. This +processing is always active, and does not need to be enabled from mts.conf. -The third way, which will override either of the previous two, is to specify a -"From:" line manually in the message draft. It will be used as provided (after -alias substitution), but to discourage email forgery, the user's real address -will be used in the SMTP envelope "From:" and in the "Sender:" line. However, -if the system administrator has allowed address masquerading by setting -"mmailid" to non-zero in mts.conf, the SMTP envelope "From:" will use the -address given in the draft "From:", and there will be no "Sender:" header. This -is useful in pretending to send mail "directly" from a remote POP3 account, or -when remote email robots give improper precedence to the envelope "From:". Note -that your MTA may still reveal your real identity (e.g. sendmail's -"X-Authentication-Warning:" header). +The third way is controlled by the "plussed_user" value of "masquerade:" line of +mts.conf. When that's turned on, setting the $USERPLUS environment variable +will result in its value being tacked onto the user's login name, following +a '+' sign. For instance, if I set $USERPLUS to "www", my "From:" line will +contain "Dan Harkless " (or "Dan.Harkless+www" if +I'm using mmailid masquerading as well). Recent versions of sendmail +automatically deliver all mail sent to \fIuser\fR+\fIstring\fR to \fIuser\fR. + +The fourth method of address masquerading is to specify a "From:" line manually +in the message draft. It will be used as provided (after alias substitution), +but normally, to discourage email forgery, the user's \fIreal\fR address will be +used in the SMTP envelope "From:" and in a "Sender:" header. However, if the +"masquerade:" line of mts.conf contains "draft_from", the SMTP envelope "From:" +will use the address given in the draft "From:", and there will be no "Sender:" +header. This is useful in pretending to send mail "directly" from a remote POP3 +account, or when remote email robots give improper precedence to the envelope +"From:". Note that your MTA may still reveal your real identity (e.g. +sendmail's "X-Authentication-Warning:" header). .Fi ^%etcdir%/mts.conf~^nmh mts configuration file diff --git a/uip/post.c b/uip/post.c index 66d978c..abc2285 100644 --- a/uip/post.c +++ b/uip/post.c @@ -283,7 +283,7 @@ static char *fill_in = NULL; static char *partno = NULL; static int queued = 0; -extern int MMailids; +extern boolean draft_from_masquerading; /* defined in mts.c */ /* * static prototypes @@ -768,15 +768,16 @@ putfmt (char *name, char *str, FILE *out) continue; } - if (MMailids && ((msgstate == RESENT) - ? (hdr->set & MRFM) - : (hdr->set & MFRM))) + if (draft_from_masquerading && ((msgstate == RESENT) + ? (hdr->set & MRFM) + : (hdr->set & MFRM))) /* The user manually specified a [Resent-]From: address in - their draft and mts.conf turned on "mmailid", so we'll - set things up to use the actual email address embedded in - the draft [Resent-]From: (after alias substitution, and - without the GECOS full name or angle brackets) as the - envelope From:. */ + their draft and the "masquerade:" line in mts.conf + doesn't contain "draft_from", so we'll set things up to + use the actual email address embedded in the draft + [Resent-]From: (after alias substitution, and without the + GECOS full name or angle brackets) as the envelope + From:. */ strncpy(from, auxformat(mp, 0), sizeof(from) - 1); if (hdr->flags & HBCC) @@ -799,14 +800,16 @@ putfmt (char *name, char *str, FILE *out) } else { /* Address includes a host, so no alias substitution is needed. */ - if (MMailids && ((msgstate == RESENT) - ? (hdr->set & MRFM) - : (hdr->set & MFRM))) - /* The user manually specified a [Resent-]From: address in their - draft and mts.conf turned on "mmailid", so we'll set things - up to use the actual email address embedded in the draft - [Resent-]From: (without the GECOS full name or angle - brackets) as the envelope From:. */ + if (draft_from_masquerading && ((msgstate == RESENT) + ? (hdr->set & MRFM) + : (hdr->set & MFRM))) + /* The user manually specified a [Resent-]From: address in + their draft and the "masquerade:" line in mts.conf + doesn't contain "draft_from", so we'll set things up to + use the actual email address embedded in the draft + [Resent-]From: (after alias substitution, and without the + GECOS full name or angle brackets) as the envelope + From:. */ strncpy(from, auxformat(mp, 0), sizeof(from) - 1); if (hdr->flags & HBCC) @@ -891,10 +894,11 @@ finish_headers (FILE *out) (int) getpid (), (long) tclock, LocalName ()); if (msgflags & MFRM) { /* There was already a From: in the draft. Don't add one. */ - if (!MMailids) - /* mts.conf didn't turn on mmailid, so we'll reveal the - user's actual account@thismachine address in a Sender: - header (and use it as the envelope From: later). */ + if (!draft_from_masquerading) + /* mts.conf didn't contain "masquerade:[...]draft_from[...]" + so we'll reveal the user's actual account@thismachine + address in a Sender: header (and use it as the envelope + From: later). */ fprintf (out, "Sender: %s\n", from); } else @@ -929,11 +933,11 @@ finish_headers (FILE *out) (int) getpid (), (long) tclock, LocalName ()); if (msgflags & MRFM) { /* There was already a Resent-From: in draft. Don't add one. */ - if (!MMailids) - /* mts.conf didn't turn on mmailid, so we'll reveal the - user's actual account@thismachine address in a - Resent-Sender: header (and use it as the envelope From: - later). */ + if (!draft_from_masquerading) + /* mts.conf didn't contain "masquerade:[...]draft_from[...]" + so we'll reveal the user's actual account@thismachine + address in a Sender: header (and use it as the envelope + From: later). */ fprintf (out, "Resent-Sender: %s\n", from); } else diff --git a/zotnet/mts/mts.c b/zotnet/mts/mts.c index 26e4807..0951c4c 100644 --- a/zotnet/mts/mts.c +++ b/zotnet/mts/mts.c @@ -60,9 +60,11 @@ char *mmdlm2 = "\001\001\001\001\n"; static char username[BUFSIZ]; static char fullname[BUFSIZ]; -/* variables for username masquerading */ -int MMailids = 0; /* used from post.c as well as here */ -static char *mmailid = "0"; +/* Variables for username masquerading: */ + boolean draft_from_masquerading = FALSE; /* also used from post.c */ +static boolean mmailid_masquerading = FALSE; +static boolean plussed_user_masquerading = FALSE; +static char* masquerade = ""; /* @@ -128,7 +130,7 @@ static struct bind binds[] = { { "uucplfil", &uucplfil }, { "mmdelim1", &mmdlm1 }, { "mmdelim2", &mmdlm2 }, - { "mmailid", &mmailid }, + { "masquerade", &masquerade }, #if defined(SENDMTS) || defined(SMTPMTS) { "hostable", &hostable }, @@ -196,8 +198,17 @@ mts_init (char *name) } fclose (fp); - MMailids = atoi (mmailid); + Everyone = atoi (everyone); + + if (strstr(masquerade, "draft_from") != NULL) + draft_from_masquerading = TRUE; + + if (strstr(masquerade, "mmailid") != NULL) + mmailid_masquerading = TRUE; + + if (strstr(masquerade, "plussed_user") != NULL) + plussed_user_masquerading = TRUE; } @@ -400,7 +411,6 @@ getuserinfo (void) || pw->pw_name == NULL || *pw->pw_name == '\0') { #endif /* KPOP */ - strncpy (username, "unknown", sizeof(username)); snprintf (fullname, sizeof(fullname), "The Unknown User-ID (%d)", (int) getuid ()); @@ -409,15 +419,26 @@ getuserinfo (void) np = pw->pw_gecos; - /* - * Do mmailid (username masquerading) processing. The GECOS - * field should have the form "Full Name ". For instance, - * "Dan Harkless ". Naturally, you'll want your MTA to have - * an alias (e.g. in /etc/aliases) from "fakeusername" to your account name. - */ + /* Get the user's real name from the GECOS field. Stop once we hit a ',', + which some OSes use to separate other 'finger' information in the GECOS + field, like phone number. Also, if mmailid masquerading is turned on due + to "mmailid" appearing on the "masquerade:" line of mts.conf, stop if we + hit a '<' (which should precede any ','s). */ #ifndef BSD42 - for (cp = fullname; *np && *np != (MMailids ? '<' : ','); *cp++ = *np++) - continue; + if (mmailid_masquerading) + /* Stop at ',' or '<'. */ + for (cp = fullname; *np != '\0' && *np != ',' && *np != '<'; + *cp++ = *np++) + continue; + else + /* Allow '<' as a legal character of the user's name. This code is + basically a duplicate of the code above the "else" -- we don't + collapse it down to one copy and put the mmailid_masquerading check + inside the loop with "(x ? y : z)" because that's inefficient and the + value'll never change while it's in there. */ + for (cp = fullname; *np != '\0' && *np != ','; + *cp++ = *np++) + continue; #else /* BSD42 */ /* On BSD(-derived) systems, the system utilities that deal with the GECOS field (finger, mail, sendmail, etc.) translate any '&' character in it to @@ -425,30 +446,69 @@ getuserinfo (void) fingering a user "bob" with the GECOS field "& Jones" would reveal him to be "In real life: Bob Jones". Surprisingly, though, the OS doesn't do the translation for you, so we have to do it manually here. */ - for (cp = fullname; *np && *np != (MMailids ? '<' : ','); ) { - if (*np == '&') { /* blech! */ - strcpy (cp, pw->pw_name); - *cp = toupper(*cp); - while (*cp) - cp++; - np++; - } else { - *cp++ = *np++; + if (mmailid_masquerading) + /* Stop at ',' or '<'. */ + for (cp = fullname; + *np != '\0' && *np != ',' && *np != '<';) { + if (*np == '&') { /* blech! */ + strcpy (cp, pw->pw_name); + *cp = toupper(*cp); + while (*cp) + cp++; + np++; + } else { + *cp++ = *np++; + } + } + else + /* Allow '<' as a legal character of the user's name. This code is + basically a duplicate of the code above the "else" -- we don't + collapse it down to one copy and put the mmailid_masquerading check + inside the loop with "(x ? y : z)" because that's inefficient and the + value'll never change while it's in there. */ + for (cp = fullname; + *np != '\0' && *np != ',';) { + if (*np == '&') { /* blech! */ + strcpy (cp, pw->pw_name); + *cp = toupper(*cp); + while (*cp) + cp++; + np++; + } else { + *cp++ = *np++; + } } - } #endif /* BSD42 */ - *cp = '\0'; - if (MMailids) { + + if (mmailid_masquerading) { + /* Do mmailid processing. The GECOS field should have the form + "Full Name ". For instance, + "Dan Harkless ". Naturally, you'll want your MTA to + have an alias (e.g. in /etc/aliases) from "fakeusername" to your + account name. */ if (*np) np++; for (cp = username; *np && *np != '>'; *cp++ = *np++) continue; *cp = '\0'; } - if (MMailids == 0 || *np == '\0') + if (!mmailid_masquerading || *np == '\0') strncpy (username, pw->pw_name, sizeof(username)); + if (plussed_user_masquerading) { + /* Tack on '+' and $USERPLUS environment variable to actual username. + Presumably the local MTA (e.g. sendmail) has been set up to deliver + all mail sent to + to . */ + char* plussed_user_addon = getenv("USERPLUS"); + + if (plussed_user_addon != NULL && *plussed_user_addon != '\0') + snprintf(username, sizeof(username), "%s+%s", + username, plussed_user_addon); + } + + /* The $SIGNATURE environment variable overrides the GECOS field's idea of + your real name. */ if ((cp = getenv ("SIGNATURE")) && *cp) strncpy (fullname, cp, sizeof(fullname)); -- 1.7.10.4