AUTH_HEIMDAL_GSSAPI=yes
AUTH_PLAINTEXT=yes
AUTH_SPA=yes
+AUTH_TLS=yes
.endd
in &_Local/Makefile_&, respectively. The first of these supports the CRAM-MD5
authentication mechanism (RFC 2195), and the second provides an interface to
the PLAIN authentication mechanism (RFC 2595) or the LOGIN mechanism, which is
not formally documented, but used by several MUAs. The seventh authenticator
supports Microsoft's &'Secure Password Authentication'& mechanism.
+The eighth is an Exim authenticator but not an SMTP one;
+instead it can use information from a TLS negotiation.
The authenticators are configured using the same syntax as other drivers (see
section &<<SECTfordricon>>&). If no authenticators are required, no
+. ////////////////////////////////////////////////////////////////////////////
+. ////////////////////////////////////////////////////////////////////////////
+
+.new
+.chapter "The tls authenticator" "CHAPtlsauth"
+.scindex IIDtlsauth1 "&(tls)& authenticator"
+.scindex IIDtlsauth2 "authenticators" "&(tls)&"
+.cindex "authentication" "Client Certificate"
+.cindex "authentication" "X509"
+.cindex "Certificate-based authentication"
+The &(tls)& authenticator provides server support for
+authentication based on client certificates.
+
+It is not an SMTP authentication mechanism and is not
+advertised by the server as part of the SMTP EHLO response.
+It is an Exim authenticator in the sense that it affects
+the protocol element of the log line, can be tested for
+by the &%authenticated%& ACL condition, and can set
+the &$authenticated_id$& variable.
+
+The client must present a verifiable certificate,
+for which it must have been requested via the
+&%tls_verify_hosts%& or &%tls_try_verify_hosts%& main options
+(see &<<CHAPTLS>>&).
+
+If an authenticator of this type is configured it is
+run before any SMTP-level communication is done,
+and can authenticate the connection.
+If it does, SMTP suthentication is not offered.
+
+A maximum of one authenticator of this type may be present.
+
+
+.cindex "options" "&(tls)& authenticator (server)"
+The &(tls)& authenticator has three server options:
+
+.option server_param1 tls string&!! unset
+.cindex "variables (&$auth1$& &$auth2$& etc)" "in &(tls)& authenticator"
+This option is expanded after the TLS negotiation and
+the result is placed in &$auth1$&.
+If the expansion is forced to fail, authentication fails. Any other expansion
+failure causes a temporary error code to be returned.
+
+.option server_param2 tls string&!! unset
+.option server_param3 tls string&!! unset
+As above, for &$auth2$& and &$auth3$&.
+
+&%server_param1%& may also be spelled &%server_param%&.
+
+
+Example:
+.code
+tls:
+ driver = tls
+ server_param1 = ${certextract {subj_altname,mail,>:} \
+ {$tls_in_peercert}}
+ server_condition = ${if forany {$auth1} \
+ {!= {0} \
+ {${lookup ldap{ldap:///\
+ mailname=${quote_ldap_dn:${lc:$item}},\
+ ou=users,LDAP_DC?mailid} {$value}{0} \
+ } } } }
+ server_set_id = ${if = {1}{${listcount:$auth1}} {$auth1}{}}
+.endd
+.ecindex IIDtlsauth1
+.ecindex IIDtlsauth2
+.wen
+
+
+Note that because authentication is traditionally an SMTP operation,
+the &%authenticated%& ACL condition cannot be used in
+a connect- or helo-ACL.
+
+
+
. ////////////////////////////////////////////////////////////////////////////
. ////////////////////////////////////////////////////////////////////////////
VRFY_CMD, EXPN_CMD, NOOP_CMD, /* RFC as requiring synchronization */
ETRN_CMD, /* This by analogy with TURN from the RFC */
STARTTLS_CMD, /* Required by the STARTTLS RFC */
+ TLS_AUTH_CMD, /* auto-command at start of SSL */
/* This is a dummy to identify the non-sync commands when pipelining */
{ "auth", sizeof("auth")-1, AUTH_CMD, TRUE, TRUE },
#ifdef SUPPORT_TLS
{ "starttls", sizeof("starttls")-1, STARTTLS_CMD, FALSE, FALSE },
+ { "tls_auth", 0, TLS_AUTH_CMD, FALSE, TRUE },
#endif
/* If you change anything above here, also fix the definitions below. */
#define CMD_LIST_EHLO 2
#define CMD_LIST_AUTH 3
#define CMD_LIST_STARTTLS 4
+#define CMD_LIST_TLS_AUTH 5
/* This list of names is used for performing the smtp_no_mail logging action.
It must be kept in step with the SCH_xxx enumerations. */
+static int
+smtp_in_auth(auth_instance *au, uschar ** s, uschar ** ss)
+{
+const uschar *set_id = NULL;
+int rc, i;
+
+/* Run the checking code, passing the remainder of the command line as
+data. Initials the $auth<n> variables as empty. Initialize $0 empty and set
+it as the only set numerical variable. The authenticator may set $auth<n>
+and also set other numeric variables. The $auth<n> variables are preferred
+nowadays; the numerical variables remain for backwards compatibility.
+
+Afterwards, have a go at expanding the set_id string, even if
+authentication failed - for bad passwords it can be useful to log the
+userid. On success, require set_id to expand and exist, and put it in
+authenticated_id. Save this in permanent store, as the working store gets
+reset at HELO, RSET, etc. */
+
+for (i = 0; i < AUTH_VARS; i++) auth_vars[i] = NULL;
+expand_nmax = 0;
+expand_nlength[0] = 0; /* $0 contains nothing */
+
+rc = (au->info->servercode)(au, smtp_cmd_data);
+if (au->set_id) set_id = expand_string(au->set_id);
+expand_nmax = -1; /* Reset numeric variables */
+for (i = 0; i < AUTH_VARS; i++) auth_vars[i] = NULL; /* Reset $auth<n> */
+
+/* The value of authenticated_id is stored in the spool file and printed in
+log lines. It must not contain binary zeros or newline characters. In
+normal use, it never will, but when playing around or testing, this error
+can (did) happen. To guard against this, ensure that the id contains only
+printing characters. */
+
+if (set_id) set_id = string_printing(set_id);
+
+/* For the non-OK cases, set up additional logging data if set_id
+is not empty. */
+
+if (rc != OK)
+ set_id = set_id && *set_id
+ ? string_sprintf(" (set_id=%s)", set_id) : US"";
+
+/* Switch on the result */
+
+switch(rc)
+ {
+ case OK:
+ if (!au->set_id || set_id) /* Complete success */
+ {
+ if (set_id) authenticated_id = string_copy_malloc(set_id);
+ sender_host_authenticated = au->name;
+ authentication_failed = FALSE;
+ authenticated_fail_id = NULL; /* Impossible to already be set? */
+
+ received_protocol =
+ (sender_host_address ? protocols : protocols_local)
+ [pextend + pauthed + (tls_in.active >= 0 ? pcrpted:0)];
+ *s = *ss = US"235 Authentication succeeded";
+ authenticated_by = au;
+ break;
+ }
+
+ /* Authentication succeeded, but we failed to expand the set_id string.
+ Treat this as a temporary error. */
+
+ auth_defer_msg = expand_string_message;
+ /* Fall through */
+
+ case DEFER:
+ if (set_id) authenticated_fail_id = string_copy_malloc(set_id);
+ *s = string_sprintf("435 Unable to authenticate at present%s",
+ auth_defer_user_msg);
+ *ss = string_sprintf("435 Unable to authenticate at present%s: %s",
+ set_id, auth_defer_msg);
+ break;
+
+ case BAD64:
+ *s = *ss = US"501 Invalid base64 data";
+ break;
+
+ case CANCELLED:
+ *s = *ss = US"501 Authentication cancelled";
+ break;
+
+ case UNEXPECTED:
+ *s = *ss = US"553 Initial data not expected";
+ break;
+
+ case FAIL:
+ if (set_id) authenticated_fail_id = string_copy_malloc(set_id);
+ *s = US"535 Incorrect authentication data";
+ *ss = string_sprintf("535 Incorrect authentication data%s", set_id);
+ break;
+
+ default:
+ if (set_id) authenticated_fail_id = string_copy_malloc(set_id);
+ *s = US"435 Internal error";
+ *ss = string_sprintf("435 Internal error%s: return %d from authentication "
+ "check", set_id, rc);
+ break;
+ }
+
+return rc;
+}
+
+
+
/*************************************************
* Initialize for SMTP incoming message *
*************************************************/
cmd_list[CMD_LIST_EHLO].is_mail_cmd = TRUE;
#ifdef SUPPORT_TLS
cmd_list[CMD_LIST_STARTTLS].is_mail_cmd = TRUE;
+cmd_list[CMD_LIST_TLS_AUTH].is_mail_cmd = TRUE;
#endif
/* Set the local signal handler for SIGTERM - it tries to end off tidily */
uschar *user_msg = NULL;
uschar *recipient = NULL;
uschar *hello = NULL;
- const uschar *set_id = NULL;
uschar *s, *ss;
BOOL was_rej_mail = FALSE;
BOOL was_rcpt = FALSE;
uschar *orcpt = NULL;
int flags;
+#if defined(SUPPORT_TLS) && defined(AUTH_TLS)
+ /* Check once per STARTTLS or SSL-on-connect for a TLS AUTH */
+ if ( tls_in.active >= 0
+ && tls_in.peercert
+ && tls_in.certificate_verified
+ && cmd_list[CMD_LIST_TLS_AUTH].is_mail_cmd
+ )
+ {
+ cmd_list[CMD_LIST_TLS_AUTH].is_mail_cmd = FALSE;
+ if (acl_smtp_auth)
+ {
+ rc = acl_check(ACL_WHERE_AUTH, NULL, acl_smtp_auth, &user_msg, &log_msg);
+ if (rc != OK)
+ {
+ done = smtp_handle_acl_fail(ACL_WHERE_AUTH, rc, user_msg, log_msg);
+ continue;
+ }
+ }
+
+ for (au = auths; au; au = au->next)
+ if (strcmpic(US"tls", au->driver_name) == 0)
+ {
+ smtp_cmd_data = NULL;
+
+ if ((c = smtp_in_auth(au, &s, &ss)) != OK)
+ log_write(0, LOG_MAIN|LOG_REJECT, "%s authenticator failed for %s: %s",
+ au->name, host_and_ident(FALSE), ss);
+ else
+ DEBUG(D_auth) debug_printf("tls auth succeeded\n");
+
+ break;
+ }
+ }
+#endif
+
switch(smtp_read_command(TRUE))
{
/* The AUTH command is not permitted to occur inside a transaction, and may
US"AUTH command used when not advertised");
break;
}
- if (sender_host_authenticated != NULL)
+ if (sender_host_authenticated)
{
done = synprot_error(L_smtp_protocol_error, 503, NULL,
US"already authenticated");
break;
}
- if (sender_address != NULL)
+ if (sender_address)
{
done = synprot_error(L_smtp_protocol_error, 503, NULL,
US"not permitted in mail transaction");
/* Check the ACL */
- if (acl_smtp_auth != NULL)
+ if (acl_smtp_auth)
{
rc = acl_check(ACL_WHERE_AUTH, NULL, acl_smtp_auth, &user_msg, &log_msg);
if (rc != OK)
as a server and which has been advertised (unless, sigh, allow_auth_
unadvertised is set). */
- for (au = auths; au != NULL; au = au->next)
- {
+ for (au = auths; au; au = au->next)
if (strcmpic(s, au->public_name) == 0 && au->server &&
- (au->advertised || allow_auth_unadvertised)) break;
- }
-
- if (au == NULL)
- {
- done = synprot_error(L_smtp_protocol_error, 504, NULL,
- string_sprintf("%s authentication mechanism not supported", s));
- break;
- }
-
- /* Run the checking code, passing the remainder of the command line as
- data. Initials the $auth<n> variables as empty. Initialize $0 empty and set
- it as the only set numerical variable. The authenticator may set $auth<n>
- and also set other numeric variables. The $auth<n> variables are preferred
- nowadays; the numerical variables remain for backwards compatibility.
-
- Afterwards, have a go at expanding the set_id string, even if
- authentication failed - for bad passwords it can be useful to log the
- userid. On success, require set_id to expand and exist, and put it in
- authenticated_id. Save this in permanent store, as the working store gets
- reset at HELO, RSET, etc. */
-
- for (i = 0; i < AUTH_VARS; i++) auth_vars[i] = NULL;
- expand_nmax = 0;
- expand_nlength[0] = 0; /* $0 contains nothing */
-
- c = (au->info->servercode)(au, smtp_cmd_data);
- if (au->set_id != NULL) set_id = expand_string(au->set_id);
- expand_nmax = -1; /* Reset numeric variables */
- for (i = 0; i < AUTH_VARS; i++) auth_vars[i] = NULL; /* Reset $auth<n> */
-
- /* The value of authenticated_id is stored in the spool file and printed in
- log lines. It must not contain binary zeros or newline characters. In
- normal use, it never will, but when playing around or testing, this error
- can (did) happen. To guard against this, ensure that the id contains only
- printing characters. */
-
- if (set_id != NULL) set_id = string_printing(set_id);
-
- /* For the non-OK cases, set up additional logging data if set_id
- is not empty. */
-
- if (c != OK)
- {
- if (set_id != NULL && *set_id != 0)
- set_id = string_sprintf(" (set_id=%s)", set_id);
- else set_id = US"";
- }
-
- /* Switch on the result */
+ (au->advertised || allow_auth_unadvertised))
+ break;
- switch(c)
+ if (au)
{
- case OK:
- if (au->set_id == NULL || set_id != NULL) /* Complete success */
- {
- if (set_id != NULL) authenticated_id = string_copy_malloc(set_id);
- sender_host_authenticated = au->name;
- authentication_failed = FALSE;
- authenticated_fail_id = NULL; /* Impossible to already be set? */
-
- received_protocol =
- (sender_host_address ? protocols : protocols_local)
- [pextend + pauthed + (tls_in.active >= 0 ? pcrpted:0)];
- s = ss = US"235 Authentication succeeded";
- authenticated_by = au;
- break;
- }
-
- /* Authentication succeeded, but we failed to expand the set_id string.
- Treat this as a temporary error. */
-
- auth_defer_msg = expand_string_message;
- /* Fall through */
-
- case DEFER:
- if (set_id != NULL) authenticated_fail_id = string_copy_malloc(set_id);
- s = string_sprintf("435 Unable to authenticate at present%s",
- auth_defer_user_msg);
- ss = string_sprintf("435 Unable to authenticate at present%s: %s",
- set_id, auth_defer_msg);
- break;
-
- case BAD64:
- s = ss = US"501 Invalid base64 data";
- break;
-
- case CANCELLED:
- s = ss = US"501 Authentication cancelled";
- break;
-
- case UNEXPECTED:
- s = ss = US"553 Initial data not expected";
- break;
-
- case FAIL:
- if (set_id != NULL) authenticated_fail_id = string_copy_malloc(set_id);
- s = US"535 Incorrect authentication data";
- ss = string_sprintf("535 Incorrect authentication data%s", set_id);
- break;
+ c = smtp_in_auth(au, &s, &ss);
- default:
- if (set_id != NULL) authenticated_fail_id = string_copy_malloc(set_id);
- s = US"435 Internal error";
- ss = string_sprintf("435 Internal error%s: return %d from authentication "
- "check", set_id, c);
- break;
+ smtp_printf("%s\r\n", s);
+ if (c != OK)
+ log_write(0, LOG_MAIN|LOG_REJECT, "%s authenticator failed for %s: %s",
+ au->name, host_and_ident(FALSE), ss);
}
-
- smtp_printf("%s\r\n", s);
- if (c != OK)
- log_write(0, LOG_MAIN|LOG_REJECT, "%s authenticator failed for %s: %s",
- au->name, host_and_ident(FALSE), ss);
+ else
+ done = synprot_error(L_smtp_protocol_error, 504, NULL,
+ string_sprintf("%s authentication mechanism not supported", s));
break; /* AUTH_CMD */
letters, so output the names in upper case, though we actually recognize
them in either case in the AUTH command. */
- if (auths != NULL)
- {
- if (verify_check_host(&auth_advertise_hosts) == OK)
- {
- auth_instance *au;
- BOOL first = TRUE;
- for (au = auths; au != NULL; au = au->next)
- {
- if (au->server && (au->advertise_condition == NULL ||
- expand_check_condition(au->advertise_condition, au->name,
- US"authenticator")))
- {
- int saveptr;
- if (first)
- {
- s = string_cat(s, &size, &ptr, smtp_code, 3);
- s = string_cat(s, &size, &ptr, US"-AUTH", 5);
- first = FALSE;
- auth_advertised = TRUE;
- }
- saveptr = ptr;
- s = string_cat(s, &size, &ptr, US" ", 1);
- s = string_cat(s, &size, &ptr, au->public_name,
- Ustrlen(au->public_name));
- while (++saveptr < ptr) s[saveptr] = toupper(s[saveptr]);
- au->advertised = TRUE;
- }
- else au->advertised = FALSE;
- }
- if (!first) s = string_cat(s, &size, &ptr, US"\r\n", 2);
- }
- }
+ if ( auths
+#if defined(SUPPORT_TLS) && defined(AUTH_TLS)
+ && !sender_host_authenticated
+#endif
+ && verify_check_host(&auth_advertise_hosts) == OK
+ )
+ {
+ auth_instance *au;
+ BOOL first = TRUE;
+ for (au = auths; au; au = au->next)
+ if (au->server && (au->advertise_condition == NULL ||
+ expand_check_condition(au->advertise_condition, au->name,
+ US"authenticator")))
+ {
+ int saveptr;
+ if (first)
+ {
+ s = string_cat(s, &size, &ptr, smtp_code, 3);
+ s = string_cat(s, &size, &ptr, US"-AUTH", 5);
+ first = FALSE;
+ auth_advertised = TRUE;
+ }
+ saveptr = ptr;
+ s = string_cat(s, &size, &ptr, US" ", 1);
+ s = string_cat(s, &size, &ptr, au->public_name,
+ Ustrlen(au->public_name));
+ while (++saveptr < ptr) s[saveptr] = toupper(s[saveptr]);
+ au->advertised = TRUE;
+ }
+ else
+ au->advertised = FALSE;
+
+ if (!first) s = string_cat(s, &size, &ptr, US"\r\n", 2);
+ }
/* Advertise TLS (Transport Level Security) aka SSL (Secure Socket Layer)
if it has been included in the binary, and the host matches
helo_seen = esmtp = auth_advertised = pipelining_advertised = FALSE;
cmd_list[CMD_LIST_EHLO].is_mail_cmd = TRUE;
cmd_list[CMD_LIST_AUTH].is_mail_cmd = TRUE;
+ cmd_list[CMD_LIST_TLS_AUTH].is_mail_cmd = TRUE;
if (sender_helo_name != NULL)
{
store_free(sender_helo_name);
git://git.exim.org / exim.git / commitdiff