Following development LAC functionality
[l2tpns.git] / radius.c
index 02b29b7..5c2ab46 100644 (file)
--- a/radius.c
+++ b/radius.c
@@ -11,6 +11,7 @@
 #include <ctype.h>
 #include <netinet/in.h>
 #include <errno.h>
+
 #include "md5.h"
 #include "constants.h"
 #include "l2tpns.h"
 #include "util.h"
 #include "cluster.h"
 
+#ifdef LAC
+#include "l2tplac.h"
+#endif
+
 extern radiust *radius;
 extern sessiont *session;
 extern tunnelt *tunnel;
@@ -230,6 +235,7 @@ void radiussend(uint16_t r, uint8_t state)
        }
        b[1] = r >> RADIUS_SHIFT;       // identifier
        memcpy(b + 4, radius[r].auth, 16);
+
        p = b + 20;
        if (s)
        {
@@ -530,6 +536,9 @@ void processrad(uint8_t *buf, int len, char socket_index)
        uint8_t routes = 0;
        int r_code;
        int r_id;
+#ifdef LAC
+       int OpentunnelReq = 0;
+#endif
 
        CSTAT(processrad);
 
@@ -629,6 +638,11 @@ void processrad(uint8_t *buf, int len, char socket_index)
                                // Extract IP, routes, etc
                                uint8_t *p = buf + 20;
                                uint8_t *e = buf + len;
+#ifdef LAC
+                               uint8_t tag;
+                               uint8_t strtemp[256];
+                               lac_reset_rad_tag_tunnel_ctxt();
+#endif
                                for (; p + 2 <= e && p[1] && p + p[1] <= e; p += p[1])
                                {
                                        if (*p == 26 && p[1] >= 7)
@@ -823,6 +837,96 @@ void processrad(uint8_t *buf, int len, char socket_index)
                                                        session[s].classlen = MAXCLASS;
                                                memcpy(session[s].class, p + 2, session[s].classlen);
                                        }
+#ifdef LAC
+                                       else if (*p == 64)
+                                       {
+                                               // Tunnel-Type
+                                               if (p[1] != 6) continue;
+                                               tag = p[2];
+                                               LOG(3, s, session[s].tunnel, "   Radius reply Tunnel-Type:%d %d\n",
+                                                       tag, ntohl(*(uint32_t *)(p + 2)) & 0xFFFFFF);
+                                               // Fill context
+                                               lac_set_rad_tag_tunnel_type(tag, ntohl(*(uint32_t *)(p + 2)) & 0xFFFFFF);
+                                               /* Request open tunnel to remote LNS*/
+                                               OpentunnelReq = 1;
+                                       }
+                                       else if (*p == 65)
+                                       {
+                                               // Tunnel-Medium-Type
+                                               if (p[1] < 6) continue;
+                                               tag = p[2];
+                                               LOG(3, s, session[s].tunnel, "   Radius reply Tunnel-Medium-Type:%d %d\n",
+                                                       tag, ntohl(*(uint32_t *)(p + 2)) & 0xFFFFFF);
+                                               // Fill context
+                                               lac_set_rad_tag_tunnel_medium_type(tag, ntohl(*(uint32_t *)(p + 2)) & 0xFFFFFF);
+                                       }
+                                       else if (*p == 67)
+                                       {
+                                               // Tunnel-Server-Endpoint
+                                               if (p[1] < 3) continue;
+                                               tag = p[2];
+                                               //If the Tag field is greater than 0x1F,
+                                               // it SHOULD be interpreted as the first byte of the following String field.
+                                               memset(strtemp, 0, 256);
+                                               if (tag > 0x1F)
+                                               {
+                                                       tag = 0;
+                                                       memcpy(strtemp, (p + 2), p[1]-2);
+                                               }
+                                               else
+                                                       memcpy(strtemp, (p + 3), p[1]-3);
+
+                                               LOG(3, s, session[s].tunnel, "   Radius reply Tunnel-Server-Endpoint:%d %s\n", tag, strtemp);
+                                               // Fill context
+                                               lac_set_rad_tag_tunnel_serv_endpt(tag, (char *) strtemp);
+                                       }
+                                       else if (*p == 69)
+                                       {
+                                               // Tunnel-Password
+                                               size_t lentemp;
+
+                                               if (p[1] < 5) continue;
+                                               tag = p[2];
+
+                                               memset(strtemp, 0, 256);
+                                               lentemp = p[1]-3;
+                                               memcpy(strtemp, (p + 3), lentemp);
+                                               if (!rad_tunnel_pwdecode(strtemp, &lentemp, config->radiussecret, radius[r].auth))
+                                               {
+                                                       LOG_HEX(3, "Error Decode Tunnel-Password, Dump Radius reponse:", p, p[1]);
+                                                       continue;
+                                               }
+
+                                               LOG(3, s, session[s].tunnel, "   Radius reply Tunnel-Password:%d %s\n", tag, strtemp);
+                                               if (strlen((char *) strtemp) > 63)
+                                               {
+                                                       LOG(1, s, session[s].tunnel, "tunnel password is too long (>63)\n");
+                                                       continue;
+                                               }
+                                               // Fill context
+                                               lac_set_rad_tag_tunnel_password(tag, (char *) strtemp);
+                                       }
+                                       else if (*p == 82)
+                                       {
+                                               // Tunnel-Assignment-Id
+                                               if (p[1] < 3) continue;
+                                               tag = p[2];
+                                               //If the Tag field is greater than 0x1F,
+                                               // it SHOULD be interpreted as the first byte of the following String field.
+                                               memset(strtemp, 0, 256);
+                                               if (tag > 0x1F)
+                                               {
+                                                       tag = 0;
+                                                       memcpy(strtemp, (p + 2), p[1]-2);
+                                               }
+                                               else
+                                                       memcpy(strtemp, (p + 3), p[1]-3);
+
+                                               LOG(3, s, session[s].tunnel, "   Radius reply Tunnel-Assignment-Id:%d %s\n", tag, strtemp);
+                                               // Fill context
+                                               lac_set_rad_tag_tunnel_assignment_id(tag, (char *) strtemp);
+                                       }
+#endif
                                }
                        }
                        else if (r_code == AccessReject)
@@ -832,6 +936,30 @@ void processrad(uint8_t *buf, int len, char socket_index)
                                break;
                        }
 
+#ifdef LAC
+                       if ((!config->disable_lac_func) && OpentunnelReq)
+                       {
+                               char assignment_id[256];
+                               // Save radius tag context to conf
+                               lac_save_rad_tag_tunnels(s);
+
+                               memset(assignment_id, 0, 256);
+                               if (!lac_rad_select_assignment_id(s, assignment_id))
+                                       break; // Error no assignment_id
+
+                               if (lac_rad_forwardtoremotelns(s, assignment_id, session[s].user))
+                               {
+                                       int ro;
+                                       // Sanity check, no local IP to session forwarded
+                                       session[s].ip = 0;
+                                       for (ro = 0; r < MAXROUTE && session[s].route[ro].ip; r++)
+                                       {
+                                               session[s].route[ro].ip = 0;
+                                       }
+                                       break;
+                               }
+                       }
+#endif
                        if (!session[s].dns1 && config->default_dns1)
                        {
                                session[s].dns1 = ntohl(config->default_dns1);
@@ -1174,3 +1302,96 @@ void processdae(uint8_t *buf, int len, struct sockaddr_in *addr, int alen, struc
        if (sendtofrom(daefd, buf, len, MSG_DONTWAIT | MSG_NOSIGNAL, (struct sockaddr *) addr, alen, local) < 0)
                LOG(0, 0, 0, "Error sending DAE response packet: %s\n", strerror(errno));
 }
+
+#ifdef LAC
+// Decrypte the encrypted Tunnel Password.
+// Defined in RFC-2868.
+// the pl2tpsecret buffer must set to 256 characters.
+// return 0 on decoding error else length of decoded l2tpsecret
+int rad_tunnel_pwdecode(uint8_t *pl2tpsecret, size_t *pl2tpsecretlen,
+                                               const char *radiussecret, const uint8_t * auth)
+{
+       MD5_CTX ctx, oldctx;
+       hasht hash;
+       int secretlen;
+       unsigned i, n, len, decodedlen;
+
+/* 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 0 1 2 3 4 5 6 7 0 1 2 3 4 6 7
+* +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+  |     Salt      |     Salt      |   String ..........
+  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+*/
+
+       len = *pl2tpsecretlen;
+
+       if (len < 2)
+       {
+               LOG(1, 0, 0, "tunnel password is too short, We need at least a salt\n");
+               return 0;
+       }
+
+       if (len <= 3)
+       {
+               pl2tpsecret[0] = 0;
+               *pl2tpsecretlen = 0;
+               LOG(1, 0, 0, "tunnel passwd is empty !!!\n");
+               return 0;
+       }
+
+       len -= 2;       /* discount the salt */
+
+       //Use the secret to setup the decryption
+       secretlen = strlen(radiussecret);
+
+       MD5_Init(&ctx);
+       MD5_Update(&ctx, (void *) radiussecret, secretlen);
+       oldctx = ctx;   /* save intermediate work */
+
+       // Set up the initial key:
+       //      b(1) = MD5(radiussecret + auth + salt)
+       MD5_Update(&ctx, (void *) auth, 16);
+       MD5_Update(&ctx, pl2tpsecret, 2);
+
+       decodedlen = 0;
+       for (n = 0; n < len; n += 16)
+       {
+               int base = 0;
+
+               if (n == 0)
+               {
+                       MD5_Final(hash, &ctx);
+
+                       ctx = oldctx;
+
+                        // the first octet, it's the 'data_len'
+                        // Check is correct
+                       decodedlen = pl2tpsecret[2] ^ hash[0];
+                       if (decodedlen >= len)
+                       {
+                               LOG(1, 0, 0, "tunnel password is too long !!!\n");
+                               return 0;
+                       }
+
+                       MD5_Update(&ctx, pl2tpsecret + 2, 16);
+                       base = 1;
+               } else
+               {
+                       MD5_Final(hash, &ctx);
+
+                       ctx = oldctx;
+                       MD5_Update(&ctx, pl2tpsecret + n + 2, 16);
+               }
+
+               for (i = base; i < 16; i++)
+               {
+                       pl2tpsecret[n + i - 1] = pl2tpsecret[n + i + 2] ^ hash[i];
+               }
+       }
+
+       if (decodedlen > 239) decodedlen = 239;
+
+       *pl2tpsecretlen = decodedlen;
+       pl2tpsecret[decodedlen] = 0;
+
+       return decodedlen;
+};
+#endif /* LAC */