// Copyright (c) 2002 FireBrick (Andrews & Arnold Ltd / Watchfront Ltd) - GPL licenced
// vim: sw=8 ts=8
-char const *cvs_id_l2tpns = "$Id: l2tpns.c,v 1.24 2004/08/26 06:22:37 fred_nerk Exp $";
+char const *cvs_id_l2tpns = "$Id: l2tpns.c,v 1.28 2004/09/20 23:34:35 fred_nerk Exp $";
#include <arpa/inet.h>
#include <assert.h>
int *radfds = NULL; // RADIUS requests file handles
int ifrfd = -1; // File descriptor for routing, etc
time_t basetime = 0; // base clock
-char hostname[1000] = ""; // us.
+char *hostname = NULL; // us.
int tunidx; // ifr_ifindex of tun device
u32 sessionid = 0; // session id for radius accounting
int syslog_log = 0; // are we logging to syslog
FILE *log_stream = NULL; // file handle for direct logging (i.e. direct into file, not via syslog).
extern int cluster_sockfd; // Intra-cluster communications socket.
-u32 last_sid = 0; // Last used PPP SID. Can I kill this?? -- mo
+u32 last_id = 0; // Last used PPP SID. Can I kill this?? -- mo
int clifd = 0; // Socket listening for CLI connections.
struct cli_session_actions *cli_session_actions = NULL; // Pending session changes requested by CLI
CONFIG("debug", debug, INT),
CONFIG("log_file", log_filename, STRING),
CONFIG("pid_file", pid_file, STRING),
+ CONFIG("hostname", hostname, STRING),
CONFIG("l2tp_secret", l2tpsecret, STRING),
CONFIG("primary_dns", default_dns1, IP),
CONFIG("secondary_dns", default_dns2, IP),
void tunnel_clean();
tunnelidt new_tunnel();
void update_config();
+int unhide_avp(u8 *avp, tunnelidt t, sessionidt s, u16 length);
static void cache_ipmap(ipt ip, int s);
static void uncache_ipmap(ipt ip);
continue;
}
log(4, ntohl(addr->sin_addr.s_addr), s, t, "Hidden AVP\n");
+ // Unhide the AVP
+ n = unhide_avp(b, t, s, n);
+ if (n == 0)
+ {
+ fatal = flags;
+ continue;
+ }
}
if (*b & 0x3C)
{
build_chap_response(b, 2, n, &chapresponse);
}
break;
+ case 13: // Response
+ // Why did they send a response? We never challenge.
+ log(2, ntohl(addr->sin_addr.s_addr), s, t, " received unexpected challenge response\n");
+ break;
+
case 14: // assigned session
asession = session[s].far = ntohs(*(u16 *) (b));
log(4, ntohl(addr->sin_addr.s_addr), s, t, " assigned session = %d\n", asession);
// TBA
break;
case 12: // ICCN
- if ( amagic == 0) amagic = time_now;
+ if (amagic == 0) amagic = time_now;
session[s].magic = amagic; // set magic number
session[s].l2tp_flags = aflags; // set flags received
log(3, ntohl(addr->sin_addr.s_addr), s, t, "Magic %X Flags %X\n", amagic, aflags);
void initdata(void)
{
int i;
+ char *p;
- _statistics = mmap(NULL, sizeof(struct Tstats), PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
- if (_statistics == MAP_FAILED)
+ if ((_statistics = shared_malloc(sizeof(struct Tstats))) == MAP_FAILED)
{
- log(0, 0, 0, 0, "Error doing mmap for _statistics: %s\n", strerror(errno));
+ log(0, 0, 0, 0, "Error doing malloc for _statistics: %s\n", strerror(errno));
exit(1);
}
- config = mmap(NULL, sizeof(struct configt), PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
- if (config == MAP_FAILED)
+ if ((config = shared_malloc(sizeof(struct configt))) == MAP_FAILED)
{
- log(0, 0, 0, 0, "Error doing mmap for configuration: %s\n", strerror(errno));
+ log(0, 0, 0, 0, "Error doing malloc for configuration: %s\n", strerror(errno));
exit(1);
}
memset(config, 0, sizeof(struct configt));
time(&config->start_time);
strncpy(config->config_file, CONFIGFILE, sizeof(config->config_file) - 1);
- tunnel = mmap(NULL, sizeof(tunnelt) * MAXTUNNEL, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
- if (tunnel == MAP_FAILED)
+ if ((tunnel = shared_malloc(sizeof(tunnelt) * MAXTUNNEL)) == MAP_FAILED);
{
- log(0, 0, 0, 0, "Error doing mmap for tunnels: %s\n", strerror(errno));
+ log(0, 0, 0, 0, "Error doing malloc for tunnels: %s\n", strerror(errno));
exit(1);
}
- session = mmap(NULL, sizeof(sessiont) * MAXSESSION, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
- if (session == MAP_FAILED)
+ if ((session = shared_malloc(sizeof(sessiont) * MAXSESSION)) == MAP_FAILED)
{
- log(0, 0, 0, 0, "Error doing mmap for sessions: %s\n", strerror(errno));
+ log(0, 0, 0, 0, "Error doing malloc for sessions: %s\n", strerror(errno));
exit(1);
}
- sess_count = mmap(NULL, sizeof(sessioncountt) * MAXSESSION, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
- if (sess_count == MAP_FAILED)
+ if ((sess_count = shared_malloc(sizeof(sessioncountt) * MAXSESSION)) == MAP_FAILED)
{
- log(0, 0, 0, 0, "Error doing mmap for sessions_count: %s\n", strerror(errno));
+ log(0, 0, 0, 0, "Error doing malloc for sessions_count: %s\n", strerror(errno));
exit(1);
}
- radius = mmap(NULL, sizeof(radiust) * MAXRADIUS, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
- if (radius == MAP_FAILED)
+ if ((radius = shared_malloc(sizeof(radiust) * MAXRADIUS)) == MAP_FAILED)
{
- log(0, 0, 0, 0, "Error doing mmap for radius: %s\n", strerror(errno));
+ log(0, 0, 0, 0, "Error doing malloc for radius: %s\n", strerror(errno));
exit(1);
}
- ip_address_pool = mmap(NULL, sizeof(ippoolt) * MAXIPPOOL, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
- if (ip_address_pool == MAP_FAILED)
+
+ if ((ip_address_pool = shared_malloc(sizeof(ippoolt) * MAXIPPOOL)) == MAP_FAILED)
{
- log(0, 0, 0, 0, "Error doing mmap for ip_address_pool: %s\n", strerror(errno));
+ log(0, 0, 0, 0, "Error doing malloc for ip_address_pool: %s\n", strerror(errno));
exit(1);
}
+
#ifdef RINGBUFFER
- ringbuffer = mmap(NULL, sizeof(struct Tringbuffer), PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
- if (ringbuffer == MAP_FAILED)
+ if ((ringbuffer = shared_malloc(sizeof(struct Tringbuffer))) == MAP_FAILED)
{
- log(0, 0, 0, 0, "Error doing mmap for ringbuffer: %s\n", strerror(errno));
+ log(0, 0, 0, 0, "Error doing malloc for ringbuffer: %s\n", strerror(errno));
exit(1);
}
memset(ringbuffer, 0, sizeof(struct Tringbuffer));
#endif
- cli_session_actions = mmap(NULL, sizeof(struct cli_session_actions) * MAXSESSION, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
- if (cli_session_actions == MAP_FAILED)
+ if ((cli_session_actions = shared_malloc(sizeof(struct cli_session_actions) * MAXSESSION))
+ == MAP_FAILED)
{
- log(0, 0, 0, 0, "Error doing mmap for cli session actions: %s\n", strerror(errno));
+ log(0, 0, 0, 0, "Error doing malloc for cli session actions: %s\n", strerror(errno));
exit(1);
}
memset(cli_session_actions, 0, sizeof(struct cli_session_actions) * MAXSESSION);
- cli_tunnel_actions = mmap(NULL, sizeof(struct cli_tunnel_actions) * MAXSESSION, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
- if (cli_tunnel_actions == MAP_FAILED)
+
+ if ((cli_tunnel_actions = shared_malloc(sizeof(struct cli_tunnel_actions) * MAXSESSION))
+ == MAP_FAILED)
{
- log(0, 0, 0, 0, "Error doing mmap for cli tunnel actions: %s\n", strerror(errno));
+ log(0, 0, 0, 0, "Error doing malloc for cli tunnel actions: %s\n", strerror(errno));
exit(1);
}
memset(cli_tunnel_actions, 0, sizeof(struct cli_tunnel_actions) * MAXSESSION);
for (i = 1; i < MAXTUNNEL- 1; i++)
tunnel[i].state = TUNNELUNDEF; // mark it as not filled in.
- if (!*hostname)
- {
- char *p;
- // Grab my hostname unless it's been specified
- gethostname(hostname, sizeof(hostname));
- if ((p = strchr(hostname, '.'))) *p = 0;
- }
+ // Grab my hostname unless it's been specified
+ gethostname(config->hostname, sizeof(config->hostname));
+ if ((p = strchr(config->hostname, '.'))) *p = 0;
+ hostname = config->hostname;
+
_statistics->start_time = _statistics->last_reset = time(NULL);
#ifdef BGP
- bgp_peers = mmap(NULL, sizeof(struct bgp_peer) * BGP_NUM_PEERS, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
- if (bgp_peers == MAP_FAILED)
+ if ((bgp_peers = shared_malloc(sizeof(struct bgp_peer) * BGP_NUM_PEERS)) == MAP_FAILED)
{
- log(0, 0, 0, 0, "Error doing mmap for bgp: %s\n", strerror(errno));
+ log(0, 0, 0, 0, "Error doing malloc for bgp: %s\n", strerror(errno));
exit(1);
}
#endif /* BGP */
for (i = 0; i < MAXSESSION; i++)
{
- if (!session[i].opened || !session[i].ip || !session[i].cin || !session[i].cout || !*session[i].user || session[i].walled_garden)
+ if (!session[i].opened || !session[i].ip || (!session[i].cin && !session[i].cout) || !*session[i].user || session[i].walled_garden)
continue;
if (!f)
{
config->debug = optdebug;
init_tbf();
- init_cli(hostname);
+ init_cli();
read_config_file();
log(0, 0, 0, 0, "L2TPNS version " VERSION "\n");
for (r = 0; r < MAXROUTE && session[s].route[r].ip; r++)
routeset(s, session[s].route[r].ip, session[s].route[r].mask, session[s].ip, 1);
- if (!session[s].sid)
+ if (!session[s].unique_id)
{
// did this session just finish radius?
log(3, session[s].ip, s, t, "Sending initial IPCP to client\n");
sendipcp(t, s);
- session[s].sid = ++last_sid;
+ session[s].unique_id = ++last_id;
}
// Run the plugin's against this new session.
cli_print(cli, "%d total sessions open.", count);
return CLI_OK;
}
+
+/* Unhide an avp.
+ *
+ * This unencodes the AVP using the L2TP CHAP secret and the
+ * previously stored random vector. It replaces the hidden data with
+ * the cleartext data and returns the length of the cleartext data
+ * (including the AVP "header" of 6 bytes).
+ *
+ * Based on code from rp-l2tpd by Roaring Penguin Software Inc.
+ */
+int unhide_avp(u8 *avp, tunnelidt t, sessionidt s, u16 length)
+{
+ MD5_CTX ctx;
+ u8 *cursor;
+ u8 digest[16];
+ u8 working_vector[16];
+ uint16_t hidden_length;
+ u8 type[2];
+ size_t done, todo;
+ u8 *output;
+
+ // Find the AVP type.
+ type[0] = *(avp + 4);
+ type[1] = *(avp + 5);
+
+ // Line up with the hidden data
+ cursor = output = avp + 6;
+
+ // Compute initial pad
+ MD5Init(&ctx);
+ MD5Update(&ctx, type, 2);
+ MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
+ MD5Update(&ctx, session[s].random_vector, session[s].random_vector_length);
+ MD5Final(digest, &ctx);
+
+ // Get hidden length
+ hidden_length = ((uint16_t) (digest[0] ^ cursor[0])) * 256 + (uint16_t) (digest[1] ^ cursor[1]);
+
+ // Keep these for later use
+ working_vector[0] = *cursor;
+ working_vector[1] = *(cursor + 1);
+ cursor += 2;
+
+ if (hidden_length > length - 8)
+ {
+ log(1, 0, s, t, "Hidden length %d too long in AVP of length %d\n", (int) hidden_length, (int) length);
+ return 0;
+ }
+
+ /* Decrypt remainder */
+ done = 2;
+ todo = hidden_length;
+ while (todo)
+ {
+ working_vector[done] = *cursor;
+ *output = digest[done] ^ *cursor;
+ ++output;
+ ++cursor;
+ --todo;
+ ++done;
+ if (done == 16 && todo)
+ {
+ // Compute new digest
+ done = 0;
+ MD5Init(&ctx);
+ MD5Update(&ctx, config->l2tpsecret, strlen(config->l2tpsecret));
+ MD5Update(&ctx, &working_vector, 16);
+ MD5Final(digest, &ctx);
+ }
+ }
+
+ return hidden_length + 6;
+}
+
projects / l2tpns.git / blobdiff