more paranoid length checking for RADIUS replies

diff --git a/radius.c b/radius.c
index 39af2df..735ae07 100644 (file)
--- a/radius.c
+++ b/radius.c
@@ -1,6 +1,6 @@
 // L2TPNS Radius Stuff
 
-char const *cvs_id_radius = "$Id: radius.c,v 1.18 2004/11/29 02:17:18 bodea Exp $";
+char const *cvs_id_radius = "$Id: radius.c,v 1.19 2004/11/30 06:50:26 bodea Exp $";
 
 #include <time.h>
 #include <stdio.h>
@@ -471,11 +471,12 @@ void processrad(u8 *buf, int len, char socket_index)
                                // Extract IP, routes, etc
                                u8 *p = buf + 20;
                                u8 *e = buf + len;
-                               for (p = buf + 20; p < e && p[1]; p += p[1])
+                               for (; p + 2 <= e && p[1] && p + p[1] <= e; p += p[1])
                                {
                                        if (*p == 8)
                                        {
                                                // Framed-IP-Address
+                                               if (p[1] < 6) continue;
                                                session[s].ip = ntohl(*(u32 *) (p + 2));
                                                session[s].ip_pool_index = -1;
                                                LOG(3, s, session[s].tunnel, "   Radius reply contains IP address %s\n",
@@ -484,6 +485,7 @@ void processrad(u8 *buf, int len, char socket_index)
                                        else if (*p == 135)
                                        {
                                                // DNS address
+                                               if (p[1] < 6) continue;
                                                session[s].dns1 = ntohl(*(u32 *) (p + 2));
                                                LOG(3, s, session[s].tunnel, "   Radius reply contains primary DNS address %s\n",
                                                        fmtaddr(htonl(session[s].dns1), 0));
@@ -491,6 +493,7 @@ void processrad(u8 *buf, int len, char socket_index)
                                        else if (*p == 136)
                                        {
                                                // DNS address
+                                               if (p[1] < 6) continue;
                                                session[s].dns2 = ntohl(*(u32 *) (p + 2));
                                                LOG(3, s, session[s].tunnel, "   Radius reply contains secondary DNS address %s\n",
                                                        fmtaddr(htonl(session[s].dns2), 0));
@@ -581,48 +584,51 @@ void processrad(u8 *buf, int len, char socket_index)
                                                        LOG(3, s, session[s].tunnel, "    Unknown filter\n");
 
                                        }
-                                       else if (*p == 26)
+                                       else if (*p == 26 && p[1] >= 7)
                                        {
                                                // Vendor-Specific Attribute
                                                int vendor = ntohl(*(int *)(p + 2));
                                                char attrib = *(p + 6);
                                                char attrib_length = *(p + 7) - 2;
+                                               char *avpair, *value, *key, *newp;
+
                                                LOG(3, s, session[s].tunnel, "   Radius reply contains Vendor-Specific.  Vendor=%d Attrib=%d Length=%d\n", vendor, attrib, attrib_length);
-                                               if (attrib_length == 0) continue;
-                                               if (attrib != 1)
-                                                       LOG(3, s, session[s].tunnel, "      Unknown vendor-specific\n");
-                                               else
+                                               if (vendor != 9 || attrib != 1)
                                                {
-                                                       char *avpair, *value, *key, *newp;
-                                                       avpair = key = calloc(attrib_length + 1, 1);
-                                                       memcpy(avpair, p + 8, attrib_length);
-                                                       LOG(3, s, session[s].tunnel, "      Cisco-Avpair value: %s\n", avpair);
-                                                       do {
-                                                               value = strchr(key, '=');
-                                                               if (!value) break;
-                                                               *value++ = 0;
-
-                                                               // Trim quotes off reply string
-                                                               if (*value == '\'' || *value == '\"')
-                                                               {
-                                                                       char *x;
-                                                                       value++;
-                                                                       x = value + strlen(value) - 1;
-                                                                       if (*x == '\'' || *x == '\"')
-                                                                               *x = 0;
-                                                               }
-
-                                                               // Run hooks
-                                                               newp = strchr(value, ',');
-                                                               if (newp) *newp++ = 0;
-                                                               {
-                                                                       struct param_radius_response p = { &tunnel[session[s].tunnel], &session[s], key, value };
-                                                                       run_plugins(PLUGIN_RADIUS_RESPONSE, &p);
-                                                               }
-                                                               key = newp;
-                                                       } while (newp);
-                                                       free(avpair);
+                                                       LOG(3, s, session[s].tunnel, "      Unknown vendor-specific\n");
+                                                       continue;
                                                }
+
+                                               if (attrib_length < 0) continue;
+
+                                               avpair = key = calloc(attrib_length + 1, 1);
+                                               memcpy(avpair, p + 8, attrib_length);
+                                               LOG(3, s, session[s].tunnel, "      Cisco-Avpair value: %s\n", avpair);
+                                               do {
+                                                       value = strchr(key, '=');
+                                                       if (!value) break;
+                                                       *value++ = 0;
+
+                                                       // Trim quotes off reply string
+                                                       if (*value == '\'' || *value == '\"')
+                                                       {
+                                                               char *x;
+                                                               value++;
+                                                               x = value + strlen(value) - 1;
+                                                               if (*x == '\'' || *x == '\"')
+                                                                       *x = 0;
+                                                       }
+
+                                                       // Run hooks
+                                                       newp = strchr(value, ',');
+                                                       if (newp) *newp++ = 0;
+                                                       {
+                                                               struct param_radius_response p = { &tunnel[session[s].tunnel], &session[s], key, value };
+                                                               run_plugins(PLUGIN_RADIUS_RESPONSE, &p);
+                                                       }
+                                                       key = newp;
+                                               } while (newp);
+                                               free(avpair);
                                        }
                                }
                        }