more lcp auth changes

[l2tpns.git] / ppp.c

diff --git a/ppp.c b/ppp.c
index 715ed2c..5ccb72a 100644 (file)
--- a/ppp.c
+++ b/ppp.c
@@ -1,6 +1,6 @@
 // L2TPNS PPP Stuff
 
-char const *cvs_id_ppp = "$Id: ppp.c,v 1.51 2005/05/07 11:57:53 bodea Exp $";
+char const *cvs_id_ppp = "$Id: ppp.c,v 1.52 2005/05/07 13:12:26 bodea Exp $";
 
 #include <stdio.h>
 #include <string.h>
@@ -24,6 +24,7 @@ extern time_t time_now;
 extern configt *config;
 
 static void initccp(tunnelidt t, sessionidt s);
+static uint8_t *add_lcp_auth(uint8_t *b, int size, int authtype);
 
 // Process PAP messages
 void processpap(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l)
@@ -404,6 +405,7 @@ void processlcp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l)
                                        {
                                                int proto = ntohs(*(uint16_t *)(o + 2));
                                                char proto_name[] = "0x0000";
+                                               uint8_t *a;
 
                                                if (proto == PPPPAP)
                                                {
@@ -436,23 +438,25 @@ void processlcp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l)
                                                        q += 4;
                                                }
 
-                                               if ((q - b + 5) > sizeof(b)) // 5 is the larger (CHAP+MD5) of the two NAKs
+                                               a = add_lcp_auth(q, sizeof(b) - (q - b), config->radius_authprefer);
+                                               if (!a)
                                                {
                                                        LOG(2, s, t, "LCP overflow for %s ConfigNak.\n", proto_name);
                                                        break;
                                                }
 
-                                               *q++ = type;
-                                               if (config->radius_authprefer == AUTHCHAP)
-                                               {
-                                                       *q++ = 5;
-                                                       *(uint16_t *) q = htons(PPPCHAP); q += 2;
-                                                       *q++ = 5; // MD5
-                                               }
-                                               else
+                                               q = a;
+
+                                               if (config->radius_authtypes != config->radius_authprefer)
                                                {
-                                                       *q++ = 4;
-                                                       *(uint16_t *) q = htons(PPPPAP); q += 2;
+                                                       a = add_lcp_auth(q, sizeof(b) - (q - b), config->radius_authtypes & ~config->radius_authprefer);
+                                                       if (!a)
+                                                       {
+                                                               LOG(2, s, t, "LCP overflow for %s ConfigNak.\n", proto_name);
+                                                               break;
+                                                       }
+
+                                                       q = a;
                                                }
 
                                                *((uint16_t *) (response + 2)) = htons(q - response); // LCP header length
@@ -505,12 +509,13 @@ void processlcp(tunnelidt t, sessionidt s, uint8_t *p, uint16_t l)
                tunnelsend(b, l + (q - b), t);
 
                if (!(session[s].flags & SF_LCP_ACKED))
-                       initlcp(t, s);
+                       sendlcp(t, s, config->radius_authprefer);
        }
        else if (*p == ConfigNak)
        {
                LOG(1, s, t, "Remote end sent a ConfigNak.  Ignoring\n");
                if (config->debug > 3) dumplcp(p, l);
+               // FIXME: handle MRU, authentication type
                return;
        }
        else if (*p == TerminateReq)
@@ -1195,8 +1200,33 @@ uint8_t *makeppp(uint8_t *b, int size, uint8_t *p, int l, tunnelidt t, sessionid
        return b;
 }
 
-// Send initial LCP ConfigReq for preferred authentication type, set magic no and MRU
-void initlcp(tunnelidt t, sessionidt s)
+static uint8_t *add_lcp_auth(uint8_t *b, int size, int authtype)
+{
+       if ((authtype == AUTHCHAP && size < 5) || size < 4)
+               return 0;
+
+       *b++ = 3; // Authentication-Protocol
+       if (authtype == AUTHCHAP)
+       {
+               *b++ = 5; // length
+               *(uint16_t *) b = htons(PPPCHAP); b += 2;
+               *b++ = 5; // MD5
+       }
+       else if (authtype == AUTHPAP)
+       {
+               *b++ = 4; // length
+               *(uint16_t *) b = htons(PPPPAP); b += 2;
+       }
+       else
+       {
+               LOG(0, 0, 0, "add_lcp_auth called with unsupported auth type %d\n", authtype);
+       }
+
+       return b;
+}
+
+// Send initial LCP ConfigReq for MRU, authentication type and magic no
+void sendlcp(tunnelidt t, sessionidt s, int authtype)
 {
        char b[500], *q, *l;
 
@@ -1216,18 +1246,7 @@ void initlcp(tunnelidt t, sessionidt s)
        *l++ = 1; *l++ = 4; // Maximum-Receive-Unit (length 4)
        *(uint16_t *) l = htons(session[s].mru); l += 2;
 
-       *l++ = 3; // Authentication-Protocol
-       if (config->radius_authprefer == AUTHCHAP)
-       {
-               *l++ = 5; // length
-               *(uint16_t *) l = htons(PPPCHAP); l += 2;
-               *l++ = 5; // MD5
-       }
-       else
-       {
-               *l++ = 4; // length
-               *(uint16_t *) l = htons(PPPPAP); l += 2;
-       }
+       l = add_lcp_auth(l, sizeof(b) - (l - b), authtype);
 
        *l++ = 5; *l++ = 6; // Magic-Number (length 6)
        *(uint32_t *) l = htonl(session[s].magic);