+/*
+ * Fernando ALVES 2013
+ * Grouped session for load balancing and fail-over
+ * GPL licenced
+ */
+
+#include <errno.h>
+#include <ctype.h>
+#include <string.h>
+#include <sys/socket.h>
+#include <linux/rtnetlink.h>
+
+#include "l2tpns.h"
+#include "util.h"
+
+#ifdef BGP
+#include "bgp.h"
+#endif
+
+union grp_iphash {
+ groupidt grp;
+ union grp_iphash *idx;
+} grp_ip_hash[256]; // Mapping from IP address to group structures.
+
+static groupidt gnextgrpid = 0;
+
+// Find gruop by IP, < 1 for not found
+//
+// Confusingly enough, this 'ip' must be
+// in _network_ order. This being the common
+// case when looking it up from IP packet headers.
+static groupidt grp_lookup_ipmap(in_addr_t ip)
+{
+ uint8_t *a = (uint8_t *) &ip;
+ union grp_iphash *h = grp_ip_hash;
+
+ if (!(h = h[*a++].idx)) return 0;
+ if (!(h = h[*a++].idx)) return 0;
+ if (!(h = h[*a++].idx)) return 0;
+
+ return h[*a].grp;
+}
+
+//
+// Take an IP address in HOST byte order and
+// add it to the grouid by IP cache.
+//
+// (It's actually cached in network order)
+//
+static void grp_cache_ipmap(in_addr_t ip, groupidt g)
+{
+ in_addr_t nip = htonl(ip); // MUST be in network order. I.e. MSB must in be ((char *) (&ip))[0]
+ uint8_t *a = (uint8_t *) &nip;
+ union grp_iphash *h = grp_ip_hash;
+ int i;
+
+ for (i = 0; i < 3; i++)
+ {
+ if (!(h[a[i]].idx || (h[a[i]].idx = calloc(256, sizeof(union grp_iphash)))))
+ return;
+
+ h = h[a[i]].idx;
+ }
+
+ h[a[3]].grp = g;
+
+ if (g > 0)
+ LOG(4, 0, 0, "Caching Group:%d ip address %s\n", g, fmtaddr(nip, 0));
+ else if (g == 0)
+ LOG(4, 0, 0, "Un-caching Group ip address %s\n", fmtaddr(nip, 0));
+}
+
+groupidt grp_groupbyip(in_addr_t ip)
+{
+ groupidt g = grp_lookup_ipmap(ip);
+
+ if (g > 0 && g < MAXGROUPE)
+ return g;
+
+ return 0;
+}
+
+// Add a route
+//
+// This adds it to the routing table, advertises it
+// via BGP if enabled, and stuffs it into the
+// 'sessionbyip' cache.
+//
+// 'ip' must be in _host_ order.
+//
+static void grp_routeset(groupidt g, in_addr_t ip, int prefixlen, int add)
+{
+ struct {
+ struct nlmsghdr nh;
+ struct rtmsg rt;
+ char buf[32];
+ } req;
+ int i;
+ in_addr_t n_ip;
+
+ if (!prefixlen) prefixlen = 32;
+
+ ip &= 0xffffffff << (32 - prefixlen);; // Force the ip to be the first one in the route.
+
+ memset(&req, 0, sizeof(req));
+
+ if (add)
+ {
+ req.nh.nlmsg_type = RTM_NEWROUTE;
+ req.nh.nlmsg_flags = NLM_F_REQUEST | NLM_F_CREATE | NLM_F_REPLACE;
+ }
+ else
+ {
+ req.nh.nlmsg_type = RTM_DELROUTE;
+ req.nh.nlmsg_flags = NLM_F_REQUEST;
+ }
+
+ req.nh.nlmsg_len = NLMSG_LENGTH(sizeof(req.rt));
+
+ req.rt.rtm_family = AF_INET;
+ req.rt.rtm_dst_len = prefixlen;
+ req.rt.rtm_table = RT_TABLE_MAIN;
+ req.rt.rtm_protocol = 42;
+ req.rt.rtm_scope = RT_SCOPE_LINK;
+ req.rt.rtm_type = RTN_UNICAST;
+
+ netlink_addattr(&req.nh, RTA_OIF, &tunidx, sizeof(int));
+ n_ip = htonl(ip);
+ netlink_addattr(&req.nh, RTA_DST, &n_ip, sizeof(n_ip));
+
+ LOG(1, 0, 0, "Route (Group) %s %s/%d\n", add ? "add" : "del", fmtaddr(htonl(ip), 0), prefixlen);
+
+ if (netlink_send(&req.nh) < 0)
+ LOG(0, 0, 0, "grp_routeset() error in sending netlink message: %s\n", strerror(errno));
+
+#ifdef BGP
+ if (add)
+ bgp_add_route(htonl(ip), prefixlen);
+ else
+ bgp_del_route(htonl(ip), prefixlen);
+#endif /* BGP */
+
+ // Add/Remove the IPs to the 'groupbyip' cache.
+ // Note that we add the zero address in the case of
+ // a network route. Roll on CIDR.
+
+ // Note that 'g == 0' implies this is the address pool.
+ // We still cache it here, because it will pre-fill
+ // the malloc'ed tree.
+ if (g)
+ {
+ if (!add) // Are we deleting a route?
+ g = 0; // Caching the session as '0' is the same as uncaching.
+
+ for (i = ip; i < ip+(1<<(32-prefixlen)) ; ++i)
+ grp_cache_ipmap(i, g);
+ }
+}
+
+// Set all route of a group
+void grp_setgrouproute(groupidt g, int add)
+{
+ int i;
+ for (i = 0; i < grpsession[g].nbroutesgrp; i++)
+ {
+ if (grpsession[g].route[i].ip != 0)
+ {
+ grp_routeset(g, grpsession[g].route[i].ip, grpsession[g].route[i].prefixlen, add);
+ }
+ }
+}
+
+// return group id by session
+groupidt grp_groupbysession(sessionidt s)
+{
+ groupidt g = 0;
+ int i;
+ for (g = gnextgrpid; g != 0; g = grpsession[g].prev)
+ {
+ for (i = 0; i < grpsession[g].nbsession; i++)
+ {
+ if (grpsession[g].sesslist[i].sid == s)
+ { // session found in group
+ return g;
+ }
+ }
+ }
+
+ return 0;
+}
+
+// Remove a session to a group
+// return 1 if OK
+void grp_removesession(groupidt g, sessionidt s)
+{
+ int i;
+
+ if (grpsession[g].nbsession <= 0)
+ return;
+
+ for (i = 0; i < grpsession[g].nbsession; i++)
+ {
+ if (grpsession[g].sesslist[i].sid == s)
+ { // session found on group
+ --grpsession[g].nbsession;
+ if (grpsession[g].nbsession == 0)
+ {
+ // Group is empty, remove it
+
+ // Del all routes
+ grp_setgrouproute(g, 0);
+
+ if (gnextgrpid == g)
+ {
+ gnextgrpid = 0;
+ }
+ else
+ {
+ groupidt g2;
+ for (g2 = gnextgrpid; g2 != 0; g2 = grpsession[g2].prev)
+ {
+ if (grpsession[g2].prev == g)
+ {
+ grpsession[g2].prev = grpsession[g].prev;
+ break;
+ }
+ }
+ }
+
+ memset(&grpsession[g], 0, sizeof(grpsession[0]));
+ }
+ else
+ {
+ // remove the session
+ memmove(&grpsession[g].sesslist[i],
+ &grpsession[g].sesslist[i+1],
+ (grpsession[g].nbsession - i) * sizeof(grpsession[g].sesslist[i]));
+ }
+ return;
+ }
+ }
+}
+
+// Add a session to a group
+// return 1 if OK
+static int grp_addsession(groupidt g, sessionidt s, uint8_t weight)
+{
+ int i;
+
+ for (i = 0; i < grpsession[g].nbsession; i++)
+ {
+ if (grpsession[g].sesslist[i].sid == s)
+ { // already in group
+ if ((!grpsession[g].sesslist[i].weight) || (weight > 1))
+ grpsession[g].sesslist[i].weight = weight; // update Weight session (for load-balancing)
+
+ return 1;
+ }
+ }
+
+ if (i >= MAXSESSINGRP)
+ {
+ LOG(1, s, session[s].tunnel, " Too many session for Group %d\n", g);
+ return 0;
+ }
+ else
+ { // add session id to group
+ if (i == 0)
+ {
+ // it's the first session of the group, set to next group
+ grpsession[g].prev = gnextgrpid;
+ gnextgrpid = g;
+ }
+ grpsession[g].sesslist[i].sid = s;
+ grpsession[g].sesslist[i].weight = weight;
+ grpsession[g].nbsession++;
+
+ return 1;
+ }
+ return 0;
+}
+
+// Add a route to a group
+// return 1 if OK
+static int grp_addroute(groupidt g, sessionidt s, in_addr_t ip, int prefixlen)
+{
+ int i;
+
+ for (i = 0; i < MAXROUTEINGRP; i++)
+ {
+ if ((i >= grpsession[g].nbroutesgrp))
+ {
+ LOG(3, s, session[s].tunnel, " Radius reply Group %d contains route for %s/%d\n",
+ g, fmtaddr(htonl(ip), 0), prefixlen);
+
+ grpsession[g].route[i].ip = ip;
+ grpsession[g].route[i].prefixlen = prefixlen;
+ grpsession[g].nbroutesgrp++;
+ return 1;
+ }
+ else if ((grpsession[g].route[i].ip == ip) && (grpsession[g].route[i].prefixlen == prefixlen))
+ {
+ // route already defined in group
+ LOG(3, s, session[s].tunnel,
+ " Radius reply Group %d contains route for %s/%d (this already defined)\n",
+ g, fmtaddr(htonl(ip), 0), prefixlen);
+
+ return 1;
+ }
+ else if (grpsession[g].route[i].ip == 0)
+ {
+ LOG(3, s, session[s].tunnel, " Radius reply Group %d contains route for %s/%d (find empty on list!!!)\n",
+ g, fmtaddr(htonl(ip), 0), prefixlen);
+
+ grpsession[g].route[i].ip = ip;
+ grpsession[g].route[i].prefixlen = prefixlen;
+ return 1;
+ }
+ }
+
+ if (i >= MAXROUTEINGRP)
+ {
+ LOG(1, s, session[s].tunnel, " Too many routes for Group %d\n", g);
+ }
+ return 0;
+}
+
+// Process Sames vendor specific attribut radius
+void grp_processvendorspecific(sessionidt s, uint8_t *pvs)
+{
+ uint8_t attrib = *pvs;
+ groupidt grpid = 0;
+ uint8_t *n = pvs + 2;
+ uint8_t *e = pvs + pvs[1];
+
+ if ((attrib >= 22) && (attrib <= 23))
+ {
+ while (n < e && isdigit(*n))
+ {
+ grpid = grpid * 10 + *n - '0';
+ n++;
+ }
+ if ((grpid == 0) || (grpid >= MAXGROUPE))
+ {
+ LOG(1, s, session[s].tunnel, " Group Attribute Id %d not allowed\n", grpid);
+ return;
+ }
+ else if (*n != ',')
+ {
+ LOG(1, s, session[s].tunnel, " Group Attribute Id not defined\n");
+ return;
+ }
+
+ if (!grp_addsession(grpid, s, 1))
+ {
+ return;
+ }
+
+ n++;
+ }
+
+ //process, Sames vendor-specific 64520
+ if (attrib == 22) //SAMES-Group-Framed-Route
+ {
+ in_addr_t ip = 0;
+ uint8_t u = 0;
+ uint8_t bits = 0;
+
+ while (n < e && (isdigit(*n) || *n == '.'))
+ {
+ if (*n == '.')
+ {
+ ip = (ip << 8) + u;
+ u = 0;
+ }
+ else
+ u = u * 10 + *n - '0';
+ n++;
+ }
+ ip = (ip << 8) + u;
+ if (*n == '/')
+ {
+ n++;
+ while (n < e && isdigit(*n))
+ bits = bits * 10 + *n++ - '0';
+ }
+ else if ((ip >> 24) < 128)
+ bits = 8;
+ else if ((ip >> 24) < 192)
+ bits = 16;
+ else
+ bits = 24;
+
+ if (!grp_addroute(grpid, s, ip, bits))
+ return;
+ }
+ else if (attrib == 23) //SAMES-Group-Session-Weight
+ {
+ uint8_t weight = 0;
+
+ while (n < e && isdigit(*n))
+ weight = weight * 10 + *n++ - '0';
+
+ if (!weight)
+ {
+ LOG(1, s, session[s].tunnel, " Group-Session-Weight 0 GroupId %d not allowed\n", grpid);
+ return;
+ }
+ if (!grp_addsession(grpid, s, weight))
+ {
+ return;
+ }
+ }
+ else
+ {
+ LOG(3, s, session[s].tunnel, " Unknown vendor-specific: 64520, Attrib: %d\n", attrib);
+ }
+}
+
+// Init data structures
+void grp_initdata()
+{
+ // Set default value (10s)
+ config->grp_txrate_average_time = 10;
+
+ if (!(grpsession = shared_malloc(sizeof(groupsesst) * MAXGROUPE)))
+ {
+ LOG(0, 0, 0, "Error doing malloc for grouped session: %s\n", strerror(errno));
+ exit(1);
+ }
+
+ memset(grpsession, 0, sizeof(grpsession[0]) * MAXGROUPE);
+}
+
+// Update time_changed of the group
+void grp_time_changed()
+{
+ groupidt g;
+
+ for (g = gnextgrpid; g != 0; g = grpsession[g].prev)
+ {
+ grpsession[g].time_changed++;
+ }
+}
+
+// return the next session can be used on the group
+sessionidt grp_getnextsession(groupidt g, in_addr_t ip)
+{
+ sessionidt s = 0, s2 = 0, s3 = 0;
+ int i;
+ uint32_t ltime_changed = 0;
+ uint32_t mintxrate = 0xFFFFFFFF;
+
+ if (g >= MAXGROUPE)
+ return 0;
+
+ if ((s = sessionbyip(ip)))
+ {
+ if ( (session[s].ppp.phase > Establish) &&
+ (time_now - session[s].last_packet <= (config->echo_timeout + 2)) )
+ {
+ int recaltxrate = 0;
+
+ for (i = 0; i < grpsession[g].nbsession; i++)
+ {
+ if (s == grpsession[g].sesslist[i].sid)
+ {
+ if ((time_now - grpsession[g].sesslist[i].mark_time) > config->grp_txrate_average_time)
+ {
+ grpsession[g].sesslist[i].mark_time = time_now;
+ recaltxrate = 1;
+ break;
+ }
+ }
+ }
+
+ if (!recaltxrate)
+ return s;
+ }
+ }
+
+ if (grpsession[g].time_changed > config->grp_txrate_average_time)
+ {
+ ltime_changed = grpsession[g].time_changed;
+ grpsession[g].time_changed = 1;
+ }
+
+ for (i = 0; i < grpsession[g].nbsession; i++)
+ {
+ if ((s2 = grpsession[g].sesslist[i].sid))
+ {
+ s3 = s2;
+ if (ltime_changed)
+ {
+ grpsession[g].sesslist[i].tx_rate = session[s2].coutgrp_delta/ltime_changed;
+ session[s2].coutgrp_delta = grpsession[g].sesslist[i].tx_rate;
+ LOG(3, s2, session[s2].tunnel, "TX Rate: %d session weight: %d\n", grpsession[g].sesslist[i].tx_rate, grpsession[g].sesslist[i].weight);
+ }
+
+ if ( session[s2].ppp.phase > Establish &&
+ (time_now - session[s2].last_packet <= (config->echo_timeout + 2)) )
+ {
+ uint32_t txrate = grpsession[g].sesslist[i].tx_rate/grpsession[g].sesslist[i].weight;
+ if (txrate < mintxrate)
+ {
+ s = s2;
+ mintxrate = txrate;
+ }
+ }
+ }
+ }
+
+ if (!s)
+ s = s3;
+
+ if (s)
+ cache_ipmap(ntohl(ip), s);
+
+ return s;
+}
projects / l2tpns.git / commitdiff