| 1 | Here are some of qmail's features. |
| 2 | |
| 3 | Setup: |
| 4 | * automatic adaptation to your UNIX variant---no configuration needed |
| 5 | * AIX, BSD/OS, FreeBSD, HP/UX, Irix, Linux, OSF/1, SunOS, Solaris, and more |
| 6 | * automatic per-host configuration (config, config-fast) |
| 7 | * quick installation---no big list of decisions to make |
| 8 | |
| 9 | Security: |
| 10 | * clear separation between addresses, files, and programs |
| 11 | * minimization of setuid code (qmail-queue) |
| 12 | * minimization of root code (qmail-start, qmail-lspawn) |
| 13 | * five-way trust partitioning---security in depth |
| 14 | * optional logging of one-way hashes, entire contents, etc. (QUEUE_EXTRA) |
| 15 | |
| 16 | Message construction (qmail-inject): |
| 17 | * RFC 822, RFC 1123 |
| 18 | * full support for address groups |
| 19 | * automatic conversion of old-style address lists to RFC 822 format |
| 20 | * sendmail hook for compatibility with current user agents |
| 21 | * header line length limited only by memory |
| 22 | * host masquerading (control/defaulthost) |
| 23 | * user masquerading ($MAILUSER, $MAILHOST) |
| 24 | * automatic Mail-Followup-To creation ($QMAILMFTFILE) |
| 25 | |
| 26 | SMTP service (qmail-smtpd): |
| 27 | * RFC 821, RFC 1123, RFC 1651, RFC 1652, RFC 1854 |
| 28 | * 8-bit clean |
| 29 | * 931/1413/ident/TAP callback (tcp-env) |
| 30 | * relay control---stop unauthorized relaying by outsiders (control/rcpthosts) |
| 31 | * no interference between relay control and forwarding |
| 32 | * tcpd hook---reject SMTP connections from known abusers |
| 33 | * automatic recognition of local IP addresses |
| 34 | * per-buffer timeouts |
| 35 | * hop counting |
| 36 | |
| 37 | Queue management (qmail-send): |
| 38 | * instant handling of messages added to queue |
| 39 | * parallelism limit (control/concurrencyremote, control/concurrencylocal) |
| 40 | * split queue directory---no slowdown when queue gets big |
| 41 | * quadratic retry schedule---old messages tried less often |
| 42 | * independent message retry schedules |
| 43 | * automatic safe queueing---no loss of mail if system crashes |
| 44 | * automatic per-recipient checkpointing |
| 45 | * automatic queue cleanups (qmail-clean) |
| 46 | * queue viewing (qmail-qread) |
| 47 | * detailed delivery statistics (qmailanalog, available separately) |
| 48 | |
| 49 | Bounces (qmail-send): |
| 50 | * QSBMF bounce messages---both machine-readable and human-readable |
| 51 | * HCMSSC support---language-independent RFC 1893 error codes |
| 52 | * double bounces sent to postmaster |
| 53 | |
| 54 | Routing by domain (qmail-send): |
| 55 | * any number of names for local host (control/locals) |
| 56 | * any number of virtual domains (control/virtualdomains) |
| 57 | * domain wildcards (control/virtualdomains) |
| 58 | * configurable percent hack support (control/percenthack) |
| 59 | * UUCP hook |
| 60 | |
| 61 | SMTP delivery (qmail-remote): |
| 62 | * RFC 821, RFC 974, RFC 1123 |
| 63 | * 8-bit clean |
| 64 | * automatic downed host backoffs |
| 65 | * artificial routing---smarthost, localnet, mailertable (control/smtproutes) |
| 66 | * per-buffer timeouts |
| 67 | * passive SMTP queue---perfect for SLIP/PPP (serialmail, available separately) |
| 68 | |
| 69 | Forwarding and mailing lists (qmail-local): |
| 70 | * address wildcards (.qmail-default, .qmail-foo-default, etc.) |
| 71 | * sendmail .forward compatibility (dot-forward, available separately) |
| 72 | * fast forwarding databases (fastforward, available separately) |
| 73 | * sendmail /etc/aliases compatibility (fastforward/newaliases) |
| 74 | * mailing list owners---automatically divert bounces and vacation messages |
| 75 | * VERPs---automatic recipient identification for mailing list bounces |
| 76 | * Delivered-To---automatic loop prevention, even across hosts |
| 77 | * automatic mailing list management (ezmlm, available separately) |
| 78 | |
| 79 | Local delivery (qmail-local): |
| 80 | * user-controlled address hierarchy---fred controls fred-anything |
| 81 | * mbox delivery |
| 82 | * reliable NFS delivery (maildir) |
| 83 | * user-controlled program delivery: procmail etc. (qmail-command) |
| 84 | * optional new-mail notification (qbiff) |
| 85 | * optional NRUDT return receipts (qreceipt) |
| 86 | * conditional filtering (condredirect, bouncesaying) |
| 87 | |
| 88 | POP3 service (qmail-popup, qmail-pop3d): |
| 89 | * RFC 1939 |
| 90 | * UIDL support |
| 91 | * TOP support |
| 92 | * APOP hook |
| 93 | * modular password checking (checkpassword, available separately) |