#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"
+#include "l2tplac.h"
+#include "pppoe.h"
+
extern radiust *radius;
extern sessiont *session;
extern tunnelt *tunnel;
}
b[1] = r >> RADIUS_SHIFT; // identifier
memcpy(b + 4, radius[r].auth, 16);
+
p = b + 20;
if (s)
{
uint8_t routes = 0;
int r_code;
int r_id;
+ int OpentunnelReq = 0;
CSTAT(processrad);
run_plugins(PLUGIN_POST_AUTH, &packet);
r_code = packet.auth_allowed ? AccessAccept : AccessReject;
+#ifndef LAC
// process auth response
if (radius[r].chap)
{
LOG(3, s, session[s].tunnel, " PAP User %s authentication %s.\n", session[s].user,
(r_code == AccessAccept) ? "allowed" : "denied");
}
+#endif
if (r_code == AccessAccept)
{
// Extract IP, routes, etc
uint8_t *p = buf + 20;
uint8_t *e = buf + len;
+ uint8_t tag;
+ uint8_t strtemp[256];
+ lac_reset_rad_tag_tunnel_ctxt();
+
for (; p + 2 <= e && p[1] && p + p[1] <= e; p += p[1])
{
if (*p == 26 && p[1] >= 7)
session[s].classlen = MAXCLASS;
memcpy(session[s].class, p + 2, session[s].classlen);
}
+ 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);
+ }
}
}
else if (r_code == AccessReject)
break;
}
+ 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
+
+ LOG(3, s, session[s].tunnel, "Select Tunnel Remote LNS for assignment_id == %s\n", 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;
+ }
+ }
+
+ // process auth response
+ if (radius[r].chap)
+ {
+ // CHAP
+ uint8_t *p = makeppp(b, sizeof(b), 0, 0, s, t, PPPCHAP, 0, 0, 0);
+ if (!p) return; // Abort!
+
+ *p = (r_code == AccessAccept) ? 3 : 4; // ack/nak
+ p[1] = radius[r].id;
+ *(uint16_t *) (p + 2) = ntohs(4); // no message
+ tunnelsend(b, (p - b) + 4, t); // send it
+
+ LOG(3, s, session[s].tunnel, " CHAP User %s authentication %s.\n", session[s].user,
+ (r_code == AccessAccept) ? "allowed" : "denied");
+ }
+ else
+ {
+ // PAP
+ uint8_t *p = makeppp(b, sizeof(b), 0, 0, s, t, PPPPAP, 0, 0, 0);
+ if (!p) return; // Abort!
+
+ // ack/nak
+ *p = r_code;
+ p[1] = radius[r].id;
+ *(uint16_t *) (p + 2) = ntohs(5);
+ p[4] = 0; // no message
+ tunnelsend(b, (p - b) + 5, t); // send it
+
+ LOG(3, s, session[s].tunnel, " PAP User %s authentication %s.\n", session[s].user,
+ (r_code == AccessAccept) ? "allowed" : "denied");
+ }
+
if (!session[s].dns1 && config->default_dns1)
{
session[s].dns1 = ntohl(config->default_dns1);
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));
}
+
+// 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;
+};
projects / l2tpns.git / blobdiff