From: Roy Marples <roy@marples.name>
Date: Thu, 7 Aug 2014 09:43:18 +0000 (+0000)
Subject: Improve error when the authentication token cannot be found.
X-Git-Tag: v6.4.4~57
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=0dc49454a909cadf5b269876c45a64d9b8dec1e6;p=thirdparty%2Fdhcpcd.git

Improve error when the authentication token cannot be found.
Improve documentation for setting up authentication.
---

diff --git a/dhcp.c b/dhcp.c
index 4b63e178..6f6d1226 100644
--- a/dhcp.c
+++ b/dhcp.c
@@ -989,7 +989,10 @@ make_message(struct dhcp_message **message,
 		auth_len = (size_t)dhcp_auth_encode(&ifo->auth,
 		    state->auth.token,
 		    NULL, 0, 4, type, NULL, 0);
-		if (auth_len > 0) {
+		if ((ssize_t)auth_len == -1)
+			syslog(LOG_ERR, "%s: dhcp_auth_encode: %m",
+			    iface->name);
+		else if (auth_len > 0) {
 			len = (size_t)((p + auth_len) - m);
 			if (auth_len > 255 || len > sizeof(*dhcp))
 				goto toobig;
@@ -997,9 +1000,7 @@ make_message(struct dhcp_message **message,
 			*p++ = (uint8_t)auth_len;
 			auth = p;
 			p += auth_len;
-		} else if ((ssize_t)auth_len == -1)
-			syslog(LOG_ERR, "%s: dhcp_auth_encode: %m",
-			    iface->name);
+		}
 	}
 
 	*p++ = DHO_END;
diff --git a/dhcp6.c b/dhcp6.c
index 86337cd0..9dcdce34 100644
--- a/dhcp6.c
+++ b/dhcp6.c
@@ -645,9 +645,11 @@ dhcp6_makemessage(struct interface *ifp)
 	if (ifo->auth.options & DHCPCD_AUTH_SEND) {
 		auth_len = (size_t)dhcp_auth_encode(&ifo->auth,
 		    state->auth.token, NULL, 0, 6, type, NULL, 0);
-		if ((ssize_t)auth_len == -1)
+		if ((ssize_t)auth_len == -1) {
+			syslog(LOG_ERR, "%s: dhcp_auth_encode: %m",
+			    ifp->name);
 			auth_len = 0;
-		else if (auth_len> 0)
+		} else if (auth_len> 0)
 			len += sizeof(*o) + auth_len;
 	} else
 		auth_len = 0; /* appease GCC */
@@ -1045,7 +1047,8 @@ logsend:
 	    dhcp6_update_auth(ifp, state->send, state->send_len) == -1)
 	{
 		syslog(LOG_ERR, "%s: dhcp6_updateauth: %m", ifp->name);
-		return -1;
+		if (errno != ESRCH)
+			return -1;
 	}
 
 	ctx = ifp->ctx->ipv6;
diff --git a/dhcpcd.conf.5.in b/dhcpcd.conf.5.in
index 4a648c02..cc10a16a 100644
--- a/dhcpcd.conf.5.in
+++ b/dhcpcd.conf.5.in
@@ -22,7 +22,7 @@
 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 .\" SUCH DAMAGE.
 .\"
-.Dd July 14, 2014
+.Dd August 7, 2014
 .Dt DHCPCD.CONF 5
 .Os
 .Sh NAME
@@ -71,7 +71,7 @@ Example:
 .D1 static ip_address=192.168.0.10/24
 .It Ic authprotocol Ar protocol Ar algorithm Ar rdm
 Authenticate DHCP messages.
-See the Supported Protocols section.
+See the Supported Authentication Protocols section.
 .It Ic authtoken Ar secretid Ar realm Ar expire Ar key
 Define a shared key for use in authentication.
 .Ar realm can be "" to for use with the
@@ -84,6 +84,18 @@ You can use the keyword
 or
 .Ar 0
 which means the token never expires.
+For the token protocol,
+.Ar secretid
+needs to be 0 and
+.Ar realm
+needs to be "".
+If
+.Nm dhcpcd
+has the error
+.D1 dhcp_auth_encode: Invalid argument
+then it means that
+.Nm dhcpcd
+could not find the correct authentication token in your configuration.
 .It Ic background
 Background immediately.
 This is useful for startup scripts which don't disable link messages for
@@ -703,10 +715,10 @@ References an option from the global definition
 .D1 embed uint32 enterprise_number
 .D1 # Options defined for the enterprise number
 .D1 encap 1 ipaddress ipaddress
-.Ss Supported protocols
+.Ss Supported Authentication Protocols
 .Bl -tag -width -indent
 .It Ic token
-Sends and expects the token with the secretid 0 in each message.
+Sends and expects the token with the secretid 0 and realm of "" in each message.
 .It Ic delayedrealm
 Delayed Authentication.
 .Nm dhcpcd
@@ -723,7 +735,7 @@ This token is used to authenicate all other messages.
 .It Ic delayed
 Same as above, but without a realm.
 .El
-.Ss Supported algorithms
+.Ss Supported Authentication Algorithms
 If none specified,
 .Ic hmac-md5
 is the default.