net/ipv4/ipvs/ip_vs_proto.c

   1 /*
   2  * ip_vs_proto.c: transport protocol load balancing support for IPVS
   3  *
   4  * Version:     $Id: ip_vs_proto.c,v 1.2 2003/04/18 09:03:16 wensong Exp $
   5  *
   6  * Authors:     Wensong Zhang <wensong@linuxvirtualserver.org>
   7  *              Julian Anastasov <ja@ssi.bg>
   8  *
   9  *              This program is free software; you can redistribute it and/or
  10  *              modify it under the terms of the GNU General Public License
  11  *              as published by the Free Software Foundation; either version
  12  *              2 of the License, or (at your option) any later version.
  13  *
  14  * Changes:
  15  *
  16  */
  17
  18 #include <linux/module.h>
  19 #include <linux/kernel.h>
  20 #include <linux/skbuff.h>
  21 #include <linux/in.h>
  22 #include <linux/ip.h>
  23 #include <net/protocol.h>
  24 #include <net/tcp.h>
  25 #include <net/udp.h>
  26 #include <asm/system.h>
  27 #include <linux/stat.h>
  28 #include <linux/proc_fs.h>
  29
  30 #include <net/ip_vs.h>
  31
  32
  33 /*
  34  * IPVS protocols can only be registered/unregistered when the ipvs
  35  * module is loaded/unloaded, so no lock is needed in accessing the
  36  * ipvs protocol table.
  37  */
  38
  39 #define IP_VS_PROTO_TAB_SIZE            32      /* must be power of 2 */
  40 #define IP_VS_PROTO_HASH(proto)         ((proto) & (IP_VS_PROTO_TAB_SIZE-1))
  41
  42 static struct ip_vs_protocol *ip_vs_proto_table[IP_VS_PROTO_TAB_SIZE];
  43
  44
  45 /*
  46  *      register an ipvs protocol
  47  */
  48 static int register_ip_vs_protocol(struct ip_vs_protocol *pp)
  49 {
  50         unsigned hash = IP_VS_PROTO_HASH(pp->protocol);
  51
  52         pp->next = ip_vs_proto_table[hash];
  53         ip_vs_proto_table[hash] = pp;
  54
  55         if (pp->init != NULL)
  56                 pp->init(pp);
  57
  58         return 0;
  59 }
  60
  61
  62 /*
  63  *      unregister an ipvs protocol
  64  */
  65 static int unregister_ip_vs_protocol(struct ip_vs_protocol *pp)
  66 {
  67         struct ip_vs_protocol **pp_p;
  68         unsigned hash = IP_VS_PROTO_HASH(pp->protocol);
  69
  70         pp_p = &ip_vs_proto_table[hash];
  71         for (; *pp_p; pp_p = &(*pp_p)->next) {
  72                 if (*pp_p == pp) {
  73                         *pp_p = pp->next;
  74                         if (pp->exit != NULL)
  75                                 pp->exit(pp);
  76                         return 0;
  77                 }
  78         }
  79
  80         return -ESRCH;
  81 }
  82
  83
  84 /*
  85  *      get ip_vs_protocol object by its proto.
  86  */
  87 struct ip_vs_protocol * ip_vs_proto_get(unsigned short proto)
  88 {
  89         struct ip_vs_protocol *pp;
  90         unsigned hash = IP_VS_PROTO_HASH(proto);
  91
  92         for (pp = ip_vs_proto_table[hash]; pp; pp = pp->next) {
  93                 if (pp->protocol == proto)
  94                         return pp;
  95         }
  96
  97         return NULL;
  98 }
  99
 100
 101 /*
 102  *      Propagate event for state change to all protocols
 103  */
 104 void ip_vs_protocol_timeout_change(int flags)
 105 {
 106         struct ip_vs_protocol *pp;
 107         int i;
 108
 109         for (i = 0; i < IP_VS_PROTO_TAB_SIZE; i++) {
 110                 for (pp = ip_vs_proto_table[i]; pp; pp = pp->next) {
 111                         if (pp->timeout_change)
 112                                 pp->timeout_change(pp, flags);
 113                 }
 114         }
 115 }
 116
 117
 118 int *
 119 ip_vs_create_timeout_table(int *table, int size)
 120 {
 121         int *t;
 122
 123         t = kmalloc(size, GFP_ATOMIC);
 124         if (t == NULL)
 125                 return NULL;
 126         memcpy(t, table, size);
 127         return t;
 128 }
 129
 130
 131 /*
 132  *      Set timeout value for state specified by name
 133  */
 134 int
 135 ip_vs_set_state_timeout(int *table, int num, char **names, char *name, int to)
 136 {
 137         int i;
 138
 139         if (!table || !name || !to)
 140                 return -EINVAL;
 141
 142         for (i = 0; i < num; i++) {
 143                 if (strcmp(names[i], name))
 144                         continue;
 145                 table[i] = to * HZ;
 146                 return 0;
 147         }
 148         return -ENOENT;
 149 }
 150
 151
 152 const char * ip_vs_state_name(__u16 proto, int state)
 153 {
 154         struct ip_vs_protocol *pp = ip_vs_proto_get(proto);
 155
 156         if (pp == NULL || pp->state_name == NULL)
 157                 return "ERR!";
 158         return pp->state_name(state);
 159 }
 160
 161
 162 void
 163 ip_vs_tcpudp_debug_packet(struct ip_vs_protocol *pp,
 164                           const struct sk_buff *skb,
 165                           int offset,
 166                           const char *msg)
 167 {
 168         char buf[128];
 169         struct iphdr _iph, *ih;
 170
 171         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
 172         if (ih == NULL)
 173                 sprintf(buf, "%s TRUNCATED", pp->name);
 174         else if (ih->frag_off & __constant_htons(IP_OFFSET))
 175                 sprintf(buf, "%s %u.%u.%u.%u->%u.%u.%u.%u frag",
 176                         pp->name, NIPQUAD(ih->saddr),
 177                         NIPQUAD(ih->daddr));
 178         else {
 179                 __u16 _ports[2], *pptr
 180 ;
 181                 pptr = skb_header_pointer(skb, offset + ih->ihl*4,
 182                                           sizeof(_ports), _ports);
 183                 if (pptr == NULL)
 184                         sprintf(buf, "%s TRUNCATED %u.%u.%u.%u->%u.%u.%u.%u",
 185                                 pp->name,
 186                                 NIPQUAD(ih->saddr),
 187                                 NIPQUAD(ih->daddr));
 188                 else
 189                         sprintf(buf, "%s %u.%u.%u.%u:%u->%u.%u.%u.%u:%u",
 190                                 pp->name,
 191                                 NIPQUAD(ih->saddr),
 192                                 ntohs(pptr[0]),
 193                                 NIPQUAD(ih->daddr),
 194                                 ntohs(pptr[1]));
 195         }
 196
 197         printk(KERN_DEBUG "IPVS: %s: %s\n", msg, buf);
 198 }
 199
 200
 201 int ip_vs_protocol_init(void)
 202 {
 203         char protocols[64];
 204 #define REGISTER_PROTOCOL(p)                    \
 205         do {                                    \
 206                 register_ip_vs_protocol(p);     \
 207                 strcat(protocols, ", ");        \
 208                 strcat(protocols, (p)->name);   \
 209         } while (0)
 210
 211         protocols[0] = '\0';
 212         protocols[2] = '\0';
 213 #ifdef CONFIG_IP_VS_PROTO_TCP
 214         REGISTER_PROTOCOL(&ip_vs_protocol_tcp);
 215 #endif
 216 #ifdef CONFIG_IP_VS_PROTO_UDP
 217         REGISTER_PROTOCOL(&ip_vs_protocol_udp);
 218 #endif
 219 #ifdef CONFIG_IP_VS_PROTO_ICMP
 220         REGISTER_PROTOCOL(&ip_vs_protocol_icmp);
 221 #endif
 222 #ifdef CONFIG_IP_VS_PROTO_AH
 223         REGISTER_PROTOCOL(&ip_vs_protocol_ah);
 224 #endif
 225 #ifdef CONFIG_IP_VS_PROTO_ESP
 226         REGISTER_PROTOCOL(&ip_vs_protocol_esp);
 227 #endif
 228         IP_VS_INFO("Registered protocols (%s)\n", &protocols[2]);
 229
 230         return 0;
 231 }
 232
 233
 234 void ip_vs_protocol_cleanup(void)
 235 {
 236         struct ip_vs_protocol *pp;
 237         int i;
 238
 239         /* unregister all the ipvs protocols */
 240         for (i = 0; i < IP_VS_PROTO_TAB_SIZE; i++) {
 241                 while ((pp = ip_vs_proto_table[i]) != NULL)
 242                         unregister_ip_vs_protocol(pp);
 243         }
 244 }