- markus@cvs.openbsd.org 2013/03/07 19:27:25
[auth.h auth2-chall.c auth2.c monitor.c sshd_config.5]
add submethod support to AuthenticationMethods; ok and freedback djm@
diff --git a/ChangeLog b/ChangeLog
index 38f6fa8..7be6f7b 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -19,6 +19,9 @@
have included a style (e.g. "root:skey") when checking public key
signatures. Fixes public key and hostbased auth when the client specified
a style; ok markus@
+ - markus@cvs.openbsd.org 2013/03/07 19:27:25
+ [auth.h auth2-chall.c auth2.c monitor.c sshd_config.5]
+ add submethod support to AuthenticationMethods; ok and freedback djm@
20130418
- (djm) [config.guess config.sub] Update to last versions before they switch
diff --git a/auth.h b/auth.h
index c6fe847..7ff59f1 100644
--- a/auth.h
+++ b/auth.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: auth.h,v 1.72 2012/12/02 20:34:09 djm Exp $ */
+/* $OpenBSD: auth.h,v 1.73 2013/03/07 19:27:25 markus Exp $ */
/*
* Copyright (c) 2000 Markus Friedl. All rights reserved.
@@ -157,8 +157,9 @@
char *auth2_read_banner(void);
int auth2_methods_valid(const char *, int);
-int auth2_update_methods_lists(Authctxt *, const char *);
+int auth2_update_methods_lists(Authctxt *, const char *, const char *);
int auth2_setup_methods_lists(Authctxt *);
+int auth2_method_allowed(Authctxt *, const char *, const char *);
void privsep_challenge_enable(void);
diff --git a/auth2-chall.c b/auth2-chall.c
index 6505d40..ed1acdd 100644
--- a/auth2-chall.c
+++ b/auth2-chall.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: auth2-chall.c,v 1.36 2012/12/03 00:14:06 djm Exp $ */
+/* $OpenBSD: auth2-chall.c,v 1.37 2013/03/07 19:27:25 markus Exp $ */
/*
* Copyright (c) 2001 Markus Friedl. All rights reserved.
* Copyright (c) 2001 Per Allansson. All rights reserved.
@@ -155,7 +155,7 @@
}
/* get next device */
static int
-kbdint_next_device(KbdintAuthctxt *kbdintctxt)
+kbdint_next_device(Authctxt *authctxt, KbdintAuthctxt *kbdintctxt)
{
size_t len;
char *t;
@@ -169,9 +169,13 @@
if (len == 0)
break;
- for (i = 0; devices[i]; i++)
+ for (i = 0; devices[i]; i++) {
+ if (!auth2_method_allowed(authctxt,
+ "keyboard-interactive", devices[i]->name))
+ continue;
if (strncmp(kbdintctxt->devices, devices[i]->name, len) == 0)
kbdintctxt->device = devices[i];
+ }
t = kbdintctxt->devices;
kbdintctxt->devices = t[len] ? xstrdup(t+len+1) : NULL;
xfree(t);
@@ -221,7 +225,7 @@
debug2("auth2_challenge_start: devices %s",
kbdintctxt->devices ? kbdintctxt->devices : "<empty>");
- if (kbdint_next_device(kbdintctxt) == 0) {
+ if (kbdint_next_device(authctxt, kbdintctxt) == 0) {
auth2_challenge_stop(authctxt);
return 0;
}
diff --git a/auth2.c b/auth2.c
index e367a10..e444821 100644
--- a/auth2.c
+++ b/auth2.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: auth2.c,v 1.126 2012/12/02 20:34:09 djm Exp $ */
+/* $OpenBSD: auth2.c,v 1.127 2013/03/07 19:27:25 markus Exp $ */
/*
* Copyright (c) 2000 Markus Friedl. All rights reserved.
*
@@ -98,8 +98,12 @@
/* helper */
static Authmethod *authmethod_lookup(Authctxt *, const char *);
static char *authmethods_get(Authctxt *authctxt);
-static int method_allowed(Authctxt *, const char *);
-static int list_starts_with(const char *, const char *);
+
+#define MATCH_NONE 0 /* method or submethod mismatch */
+#define MATCH_METHOD 1 /* method matches (no submethod specified) */
+#define MATCH_BOTH 2 /* method and submethod match */
+#define MATCH_PARTIAL 3 /* method matches, submethod can't be checked */
+static int list_starts_with(const char *, const char *, const char *);
char *
auth2_read_banner(void)
@@ -316,7 +320,7 @@
}
if (authenticated && options.num_auth_methods != 0) {
- if (!auth2_update_methods_lists(authctxt, method)) {
+ if (!auth2_update_methods_lists(authctxt, method, submethod)) {
authenticated = 0;
partial = 1;
}
@@ -387,8 +391,9 @@
* methods list. Returns 1 if allowed, or no methods lists configured.
* 0 otherwise.
*/
-static int
-method_allowed(Authctxt *authctxt, const char *method)
+int
+auth2_method_allowed(Authctxt *authctxt, const char *method,
+ const char *submethod)
{
u_int i;
@@ -399,7 +404,8 @@
if (options.num_auth_methods == 0)
return 1;
for (i = 0; i < authctxt->num_auth_methods; i++) {
- if (list_starts_with(authctxt->auth_methods[i], method))
+ if (list_starts_with(authctxt->auth_methods[i], method,
+ submethod) != MATCH_NONE)
return 1;
}
return 0;
@@ -419,7 +425,8 @@
if (authmethods[i]->enabled == NULL ||
*(authmethods[i]->enabled) == 0)
continue;
- if (!method_allowed(authctxt, authmethods[i]->name))
+ if (!auth2_method_allowed(authctxt, authmethods[i]->name,
+ NULL))
continue;
if (buffer_len(&b) > 0)
buffer_append(&b, ",", 1);
@@ -442,7 +449,8 @@
if (authmethods[i]->enabled != NULL &&
*(authmethods[i]->enabled) != 0 &&
strcmp(name, authmethods[i]->name) == 0 &&
- method_allowed(authctxt, authmethods[i]->name))
+ auth2_method_allowed(authctxt,
+ authmethods[i]->name, NULL))
return authmethods[i];
debug2("Unrecognized authentication method name: %s",
name ? name : "NULL");
@@ -457,7 +465,7 @@
int
auth2_methods_valid(const char *_methods, int need_enable)
{
- char *methods, *omethods, *method;
+ char *methods, *omethods, *method, *p;
u_int i, found;
int ret = -1;
@@ -468,6 +476,8 @@
omethods = methods = xstrdup(_methods);
while ((method = strsep(&methods, ",")) != NULL) {
for (found = i = 0; !found && authmethods[i] != NULL; i++) {
+ if ((p = strchr(method, ':')) != NULL)
+ *p = '\0';
if (strcmp(method, authmethods[i]->name) != 0)
continue;
if (need_enable) {
@@ -533,15 +543,30 @@
}
static int
-list_starts_with(const char *methods, const char *method)
+list_starts_with(const char *methods, const char *method,
+ const char *submethod)
{
size_t l = strlen(method);
+ int match;
+ const char *p;
if (strncmp(methods, method, l) != 0)
- return 0;
- if (methods[l] != ',' && methods[l] != '\0')
- return 0;
- return 1;
+ return MATCH_NONE;
+ p = methods + l;
+ match = MATCH_METHOD;
+ if (*p == ':') {
+ if (!submethod)
+ return MATCH_PARTIAL;
+ l = strlen(submethod);
+ p += 1;
+ if (strncmp(submethod, p, l))
+ return MATCH_NONE;
+ p += l;
+ match = MATCH_BOTH;
+ }
+ if (*p != ',' && *p != '\0')
+ return MATCH_NONE;
+ return match;
}
/*
@@ -550,14 +575,21 @@
* if it did.
*/
static int
-remove_method(char **methods, const char *method)
+remove_method(char **methods, const char *method, const char *submethod)
{
- char *omethods = *methods;
+ char *omethods = *methods, *p;
size_t l = strlen(method);
+ int match;
- if (!list_starts_with(omethods, method))
+ match = list_starts_with(omethods, method, submethod);
+ if (match != MATCH_METHOD && match != MATCH_BOTH)
return 0;
- *methods = xstrdup(omethods + l + (omethods[l] == ',' ? 1 : 0));
+ p = omethods + l;
+ if (submethod && match == MATCH_BOTH)
+ p += 1 + strlen(submethod); /* include colon */
+ if (*p == ',')
+ p++;
+ *methods = xstrdup(p);
free(omethods);
return 1;
}
@@ -569,13 +601,15 @@
* Returns 1 if the method completed any authentication list or 0 otherwise.
*/
int
-auth2_update_methods_lists(Authctxt *authctxt, const char *method)
+auth2_update_methods_lists(Authctxt *authctxt, const char *method,
+ const char *submethod)
{
u_int i, found = 0;
debug3("%s: updating methods list after \"%s\"", __func__, method);
for (i = 0; i < authctxt->num_auth_methods; i++) {
- if (!remove_method(&(authctxt->auth_methods[i]), method))
+ if (!remove_method(&(authctxt->auth_methods[i]), method,
+ submethod))
continue;
found = 1;
if (*authctxt->auth_methods[i] == '\0') {
diff --git a/monitor.c b/monitor.c
index 34d7e18..c0471a1 100644
--- a/monitor.c
+++ b/monitor.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: monitor.c,v 1.121 2013/03/07 00:19:59 djm Exp $ */
+/* $OpenBSD: monitor.c,v 1.122 2013/03/07 19:27:25 markus Exp $ */
/*
* Copyright 2002 Niels Provos <provos@citi.umich.edu>
* Copyright 2002 Markus Friedl <markus@openbsd.org>
@@ -392,7 +392,7 @@
"with SSH protocol 1");
if (authenticated &&
!auth2_update_methods_lists(authctxt,
- auth_method)) {
+ auth_method, auth_submethod)) {
debug3("%s: method %s: partial", __func__,
auth_method);
authenticated = 0;
@@ -949,9 +949,10 @@
debug3("%s: sending authenticated: %d", __func__, authok);
mm_request_send(sock, MONITOR_ANS_BSDAUTHRESPOND, m);
- if (compat20)
- auth_method = "keyboard-interactive"; /* XXX auth_submethod */
- else
+ if (compat20) {
+ auth_method = "keyboard-interactive";
+ auth_submethod = "bsdauth";
+ } else
auth_method = "bsdauth";
return (authok != 0);
diff --git a/sshd_config.5 b/sshd_config.5
index cfa4806..4fe3c55 100644
--- a/sshd_config.5
+++ b/sshd_config.5
@@ -33,8 +33,8 @@
.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
.\"
-.\" $OpenBSD: sshd_config.5,v 1.156 2013/02/06 00:20:42 dtucker Exp $
-.Dd $Mdocdate: February 6 2013 $
+.\" $OpenBSD: sshd_config.5,v 1.157 2013/03/07 19:27:25 markus Exp $
+.Dd $Mdocdate: March 7 2013 $
.Dt SSHD_CONFIG 5
.Os
.Sh NAME
@@ -180,6 +180,20 @@
so for this example, it would not be possible to attempt password or
keyboard-interactive authentication before public key.
.Pp
+For keyboard interactive authentication it is also possible to
+restrict authentication to a specific device by appending a
+colon followed by the device identifier
+.Dq bsdauth ,
+.Dq pam ,
+or
+.Dq skey ,
+depending on the server configuration.
+For example,
+.Dq keyboard-interactive:bsdauth
+would restrict keyboard interactive authentication to the
+.Dq bsdauth
+device.
+.Pp
This option is only available for SSH protocol 2 and will yield a fatal
error if enabled if protocol 1 is also enabled.
Note that each authentication method listed should also be explicitly enabled