From c5ddb310a1f89a0560eea67879921570b046b179 Mon Sep 17 00:00:00 2001 From: Philip Hazel Date: Tue, 5 Apr 2005 14:33:27 +0000 Subject: [PATCH] Patch to fix Cyrus-SASL unavailable mechanisms problem. --- doc/doc-txt/ChangeLog | 27 ++++++++++++++++++++++++++- src/ACKNOWLEDGMENTS | 3 ++- src/src/auths/cyrus_sasl.c | 37 +++++++++++++++++++++++++++++++++---- 3 files changed, 61 insertions(+), 6 deletions(-) diff --git a/doc/doc-txt/ChangeLog b/doc/doc-txt/ChangeLog index 8a7274491..d5c658131 100644 --- a/doc/doc-txt/ChangeLog +++ b/doc/doc-txt/ChangeLog @@ -1,4 +1,4 @@ -$Cambridge: exim/doc/doc-txt/ChangeLog,v 1.109 2005/04/05 14:02:30 ph10 Exp $ +$Cambridge: exim/doc/doc-txt/ChangeLog,v 1.110 2005/04/05 14:33:27 ph10 Exp $ Change log file for Exim from version 4.21 ------------------------------------------- @@ -125,6 +125,31 @@ PH/22 Added support for macro redefinition, and (re)definition in between PH/23 The cyrus_sasl authenticator was expanding server_hostname, but then forgetting to use the resulting value; it was using the unexpanded value. +PH/24 The cyrus_sasl authenticator was advertising mechanisms for which it + hadn't been configured. The fix is from Juergen Kreileder, who + understands it better than I do: + + "Here's what I see happening with three configured cyrus_sasl + authenticators configured (plain, login, cram-md5): + + On startup auth_cyrus_sasl_init() gets called for each of these. + This means three calls to sasl_listmech() without a specified mech_list. + => SASL tests which mechs of all available mechs actually work + => three warnings about OTP not working + => the returned list contains: plain, login, cram-md5, digest-md5, ... + + With the patch, sasl_listmech() also gets called three times. But now + SASL's mech_list option is set to the server_mech specified in the the + authenticator. Or in other words, the answer from sasl_listmech() + gets limited to just the mech you're testing for (which is different + for each call.) + => the return list contains just 'plain' or 'login', 'cram-md5' or + nothing depending on the value of ob->server_mech. + + I've just tested the patch: Authentication still works fine, + unavailable mechs specified in the exim configuration are still + caught, and the auth.log warnings about OTP are gone." + A note about Exim versions 4.44 and 4.50 ---------------------------------------- diff --git a/src/ACKNOWLEDGMENTS b/src/ACKNOWLEDGMENTS index ce5402eb8..86bc64f60 100644 --- a/src/ACKNOWLEDGMENTS +++ b/src/ACKNOWLEDGMENTS @@ -1,4 +1,4 @@ -$Cambridge: exim/src/ACKNOWLEDGMENTS,v 1.19 2005/04/05 13:58:35 ph10 Exp $ +$Cambridge: exim/src/ACKNOWLEDGMENTS,v 1.20 2005/04/05 14:33:27 ph10 Exp $ EXIM ACKNOWLEDGEMENTS @@ -159,6 +159,7 @@ Alex Kiernan Patch for libradius Tom Kistner SPA server code Writing and maintaining the content scanning extension (exiscan) +Jürgen Kreileder Fix for cyrus_sasl advertisement problem Friso Kuipers Patch for GDBM problem Chris Liddiard Fix for bug in exiqsumm Chris Lightfoot Patch for -restore-times in exim_lock diff --git a/src/src/auths/cyrus_sasl.c b/src/src/auths/cyrus_sasl.c index 849c3d1c0..8651dc605 100644 --- a/src/src/auths/cyrus_sasl.c +++ b/src/src/auths/cyrus_sasl.c @@ -1,4 +1,4 @@ -/* $Cambridge: exim/src/src/auths/cyrus_sasl.c,v 1.2 2005/04/05 14:02:30 ph10 Exp $ */ +/* $Cambridge: exim/src/src/auths/cyrus_sasl.c,v 1.3 2005/04/05 14:33:27 ph10 Exp $ */ /************************************************* * Exim - an Internet mail transport agent * @@ -7,7 +7,7 @@ /* Copyright (c) University of Cambridge 1995 - 2003 */ /* See the file NOTICE for conditions of use and distribution. */ -/* This code was contributed by Matthew Byng-Maddick */ +/* This code was originally contributed by Matthew Byng-Maddick */ /* Copyright (c) A L Digital 2004 */ @@ -71,18 +71,42 @@ auth_cyrus_sasl_options_block auth_cyrus_sasl_option_defaults = { enable consistency checks to be done, or anything else that needs to be set up. */ + +/* Auxiliary function, passed in data to sasl_server_init(). */ + +static int +mysasl_config(void *context, + const char *plugin_name, + const char *option, + const char **result, + unsigned int *len) +{ +if (context && !strcmp(option, "mech_list")) + { + *result = context; + if (len != NULL) *len = strlen(*result); + return SASL_OK; + } +return SASL_FAIL; +} + +/* Here's the real function */ + void auth_cyrus_sasl_init(auth_instance *ablock) { auth_cyrus_sasl_options_block *ob = (auth_cyrus_sasl_options_block *)(ablock->options_block); -sasl_callback_t cbs[]={{SASL_CB_LIST_END, NULL, NULL}}; -sasl_conn_t *conn; uschar *list, *listptr, *buffer; int rc, i; unsigned int len; uschar *rs_point; +sasl_conn_t *conn; +sasl_callback_t cbs[]={ + {SASL_CB_GETOPT, NULL, NULL }, + {SASL_CB_LIST_END, NULL, NULL}}; + /* default the mechanism to our "public name" */ if(ob->server_mech == NULL) ob->server_mech=string_copy(ablock->public_name); @@ -90,7 +114,12 @@ if(ob->server_mech == NULL) /* we're going to initialise the library to check that there is an * authenticator of type whatever mechanism we're using */ + +cbs[0].proc = &mysasl_config; +cbs[0].context = ob->server_mech; + rc=sasl_server_init(cbs, "exim"); + if( rc != SASL_OK ) log_write(0, LOG_PANIC_DIE|LOG_CONFIG_FOR, "%s authenticator: " "couldn't initialise Cyrus SASL library.", ablock->name); -- 2.25.1