nhrpd: Add topotest for retrying resolution request

Modified nhrp_topo topotest to test for newly added resolution
request retry feature. Changes to the topotest include adding a spoke to the
existing nhrp_topo topotest so that a topology with two spokes and hub
can be used to create shortcuts and test the sending/resending of
resolution requests and responses between spoke and hub.The resolution
request retry feature was tested by blocking incoming resolution requests on a
receiving nodes to stop the creation of a successful shortcut - which
then triggered the sending spoke to retry sending resolution requests

Also modified nhrp_connection_authorized(). Initially, when writing debug
informaton about incoming NHRP packets with authentication enabled,
the nhrp_connection_authorized() function would print the
passphrase of the incoming packet as if it were a null terminated
string. This meant that if the passphrase on the incoming packet
had non ASCII-complient bytes in it, it would attempt to print those
bytes anyway. There was also no check that the size of the passphrase in
the incoming packet matched the size of the passphrase on the interface.

Moved CISCO_PASS_LENGTH_LEN from nhrp_vty.c to nhrp_protocol.h
for easier access  to the macro in other files

Signed-off-by: Joshua Muthii <jmuthii@labn.net>

nhrpd/nhrp_peer.c

@@ -1169,22 +1169,55 @@ static bool nhrp_connection_authorized(struct nhrp_packet_parser *pp)
 	struct nhrp_extension_header *ext;
 	struct zbuf *extensions, pl;
 	int cmp = 1;
+	int pl_pass_length, auth_pass_length;
+	size_t auth_size, pl_size;
 
 	extensions = zbuf_alloc(zbuf_used(&pp->extensions));
 	zbuf_copy_peek(extensions, &pp->extensions, zbuf_used(&pp->extensions));
 	while ((ext = nhrp_ext_pull(extensions, &pl)) != NULL) {
 		switch (htons(ext->type) & ~NHRP_EXTENSION_FLAG_COMPULSORY) {
 		case NHRP_EXTENSION_AUTHENTICATION:
-			cmp = memcmp(auth->buf, pl.buf, zbuf_size(auth));
+			/* Size of authentication extensions
+			 * (varies based on password length)
+			 */
+			auth_size = zbuf_size(auth);
+			pl_size = zbuf_size(&pl);
 			auth_ext = (struct nhrp_cisco_authentication_extension *)
 					   auth->buf;
-			debugf(NHRP_DEBUG_COMMON,
-			       "Processing Authentication Extension for (%s:%s|%d)",
-			       auth_ext->secret,
-			       ((struct nhrp_cisco_authentication_extension *)
-					pl.buf)
-				       ->secret,
-			       cmp);
+
+			if (auth_size == pl_size)
+				cmp = memcmp(auth_ext, pl.buf, auth_size);
+			else
+				cmp = 1;
+
+			if (unlikely(debug_flags & NHRP_DEBUG_COMMON)) {
+				/* 4 bytes in nhrp_cisco_authentication_extension are allocated
+				 * toward the authentication type. The remaining bytes are used for the
+				 * password - so the password length is just the length of the extension - 4
+				 */
+				auth_pass_length = (auth_size - 4);
+				pl_pass_length = (pl_size - 4);
+				/* Because characters are to be printed in HEX, (2* the max pass length) + 1
+				 * is needed for the string representation
+				 */
+				char auth_pass[(2 * NHRP_CISCO_PASS_LEN) + 1] = { 0 },
+					       pl_pass[(2 * NHRP_CISCO_PASS_LEN) + 1] = { 0 };
+				/* Converting bytes in buffer to HEX and saving output as a string -
+				 * Passphrase is converted to HEX in order to avoid printing
+				 * non ACII-compliant characters
+				 */
+				for (int i = 0; i < (auth_pass_length); i++)
+					snprintf(auth_pass + (i * 2), 3, "%02X",
+						 auth_ext->secret[i]);
+				for (int i = 0; i < (pl_pass_length); i++)
+					snprintf(pl_pass + (i * 2), 3, "%02X",
+						 ((struct nhrp_cisco_authentication_extension *)pl.buf)
+							 ->secret[i]);
+
+				debugf(NHRP_DEBUG_COMMON,
+				       "Processing Authentication Extension for (%s:%s|%d)",
+				       auth_pass, pl_pass, cmp);
+			}
 			break;
 		default:
 			/* Ignoring all received extensions except Authentication*/

nhrpd/nhrp_protocol.h

@@ -73,6 +73,7 @@
 
 /* NHRP Authentication extension types (ala Cisco) */
 #define NHRP_AUTHENTICATION_PLAINTEXT		0x00000001
+#define NHRP_CISCO_PASS_LEN			8
 
 /* NHRP Packet Structures */
 struct nhrp_packet_header {

nhrpd/nhrp_vty.c

@@ -467,7 +467,6 @@ DEFUN(if_no_nhrp_holdtime, if_no_nhrp_holdtime_cmd,
 	return CMD_SUCCESS;
 }
 
-#define NHRP_CISCO_PASS_LEN 8
 DEFPY(if_nhrp_authentication, if_nhrp_authentication_cmd,
       AFI_CMD "nhrp authentication PASSWORD$password",
       AFI_STR

tests/topotests/nhrp_topo/r1/nhrp_shortcut_present.json

@@ -0,0 +1,14 @@
+{
+  "attr":{
+    "entriesCount":1
+  },
+  "table":[
+    {
+      "type":"dynamic",
+      "prefix":"192.168.4.0\/24",
+      "via":"10.255.255.4",
+      "identity":""
+    }
+  ]
+}
+

tests/topotests/nhrp_topo/r1/zebra.conf

@@ -10,3 +10,4 @@ exit
 interface r1-eth1
  ip address 192.168.1.1/24
 !
+ip route 0.0.0.0/0 10.255.255.2

tests/topotests/nhrp_topo/r2/nhrp4_cache.json

@@ -1,8 +1,19 @@
 {
   "attr":{
-    "entriesCount":2
+    "entriesCount":3
   },
   "table":[
+    {
+      "interface":"r2-gre0",
+      "type":"dynamic",
+      "protocol":"10.255.255.4",
+      "nbma":"10.1.1.4",
+      "claimed_nbma":"10.1.1.4",
+      "used":false,
+      "timeout":true,
+      "auth":false,
+      "identity":""
+    },
     {
       "interface":"r2-gre0",
       "type":"local",

tests/topotests/nhrp_topo/r2/nhrp_route4.json

@@ -12,7 +12,31 @@
       "installed":true,
       "internalNextHopNum":1,
       "internalNextHopActiveNum":1,
-      "nexthops":[
+      "nexthops": [
+        {
+          "fib":true,
+          "directlyConnected":true,
+          "interfaceName":"r2-gre0",
+          "active":true
+        }
+      ]
+    }
+  ],
+  "10.255.255.4\/32": [
+    {
+      "prefix":"10.255.255.4\/32",
+      "prefixLen":32,
+      "protocol":"nhrp",
+      "vrfId":0,
+      "vrfName":"default",
+      "selected":true,
+      "destSelected":true,
+      "distance":10,
+      "metric":0,
+      "installed":true,
+      "internalNextHopNum":1,
+      "internalNextHopActiveNum":1,
+      "nexthops": [
         {
           "fib":true,
           "directlyConnected":true,

tests/topotests/nhrp_topo/r2/zebra.conf

@@ -1,3 +1,4 @@
+ip forwarding
 interface r2-eth0
  ip address 10.2.1.2/24
 !
@@ -10,3 +11,5 @@ interface r2-gre0
 interface r2-eth1
  ip address 192.168.2.2/24
 !
+ip route 192.168.4.4/24 10.255.255.4
+ip route 192.168.1.1/24 10.255.255.1

tests/topotests/nhrp_topo/r4/nhrp4_cache.json

@@ -0,0 +1,30 @@
+{
+  "attr":{
+    "entriesCount":2
+  },
+  "table":[
+    {
+      "interface":"r4-gre0",
+      "type":"local",
+      "protocol":"10.255.255.4",
+      "nbma":"10.1.1.4",
+      "claimed_nbma":"10.1.1.4",
+      "used":false,
+      "timeout":false,
+      "auth":false,
+      "identity":"-"
+    },
+    {
+      "interface":"r4-gre0",
+      "type":"nhs",
+      "protocol":"10.255.255.2",
+      "nbma":"10.2.1.2",
+      "claimed_nbma":"10.2.1.2",
+      "used":false,
+      "timeout":true,
+      "auth":false,
+      "identity":""
+    }
+  ]
+}
+

tests/topotests/nhrp_topo/r4/nhrp_route4.json

@@ -0,0 +1,26 @@
+{
+  "10.255.255.2\/32": [
+    {
+      "prefix": "10.255.255.2\/32",
+      "prefixLen": 32,
+      "protocol": "nhrp",
+      "vrfId": 0,
+      "vrfName": "default",
+      "selected": true,
+      "destSelected": true,
+      "distance": 10,
+      "metric": 0,
+      "installed": true,
+      "internalNextHopNum": 1,
+      "internalNextHopActiveNum": 1,
+      "nexthops": [
+        {
+          "fib": true,
+          "directlyConnected": true,
+          "interfaceName": "r4-gre0",
+          "active": true
+        }
+      ]
+    }
+  ]
+}

tests/topotests/nhrp_topo/r4/nhrpd.conf

@@ -0,0 +1,11 @@
+log stdout debugging
+debug nhrp all
+interface r4-gre0
+ ip nhrp authentication secret
+ ip nhrp holdtime 10
+ ip nhrp shortcut
+ ip nhrp network-id 42
+ ip nhrp nhs dynamic nbma 10.2.1.2
+ ip nhrp registration no-unique
+ tunnel source r4-eth0
+exit

tests/topotests/nhrp_topo/r4/zebra.conf

@@ -0,0 +1,13 @@
+interface r4-eth0
+ ip address 10.1.1.4/24
+!
+ip route 10.2.1.0/24 10.1.1.3
+interface r4-gre0
+ ip address 10.255.255.4/32
+ no link-detect
+ ipv6 nd suppress-ra
+exit
+interface r4-eth1
+ ip address 192.168.4.4/24
+!
+ip route 0.0.0.0/0 10.255.255.2