quagga.try1.c

wifi 无线网络路由协议OLSR linux下C代码

/* 
 *  (C) 2006 by Immo 'FaUl' Wehrenberg <[e-mail]>
 *  
 *  This code is covered by the GPLv2
 *   
 */

#include <stdint.h>
#ifdef MY_DEBUG
#include <stdio.h>
#endif
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#define HAVE_SOCKLEN_T
#include <quagga/zebra.h>
#include "quagga.h"

#ifdef OLSR_PLUGIN
#include "olsr.h"
#include "log.h"
#include "defs.h"
#include "local_hna_set.h"
#endif

#define ZAPI_MESSAGE_NEXTHOP  0x01
#define ZAPI_MESSAGE_IFINDEX  0x02
#define ZAPI_MESSAGE_DISTANCE 0x04
#define ZAPI_MESSAGE_METRIC   0x08


#define STATUS_CONNECTED 1
#define BUFSIZE 1024
static char status = 0;

static int zsock; // Socket to zebra...
struct ipv4_route *quagga_routes = 0; // routes currently exportet to zebra


/* prototypes ntern */
static char *try_read (ssize_t *);
static char* zebra_route_packet (struct ipv4_route r, ssize_t *);
static int parse_interface_add (char *, size_t);
static int parse_interface_delete (char *, size_t);
static int parse_interface_up (char *, size_t);
static int parse_interface_down (char *, size_t);
static int parse_interface_address_add (char *, size_t);
static int parse_interface_address_delete (char *, size_t);
static int parse_ipv4_route (char *, size_t, struct ipv4_route *);
static int ipv4_route_add (char *, size_t);
static int ipv4_route_delete (char *, size_t);
static int parse_ipv6_route_add (char*, size_t);
static uint32_t prefixlentomask (uint8_t);
static void free_ipv4_route (struct ipv4_route);
static void update_olsr_zebra_routes (struct ipv4_route*, struct ipv4_route*);
static struct ipv4_route *zebra_create_ipv4_route_table_entry (uint32_t,
							       uint32_t,
							       uint32_t);
static struct ipv4_route *zebra_create_ipv4_route_table (void);
static void zebra_free_ipv4_route_table (struct ipv4_route*);
static uint8_t masktoprefixlen (uint32_t);



#ifdef MY_DEBUG
static void dump_ipv4_route (struct ipv4_route r, char *c) {
  int i = 0, x = 0;

  puts (c);
  printf("type: %d\n", r.type);
  puts("flags:");
  printf("  Internal: %s\n",r.flags&ZEBRA_FLAG_INTERNAL?"yes":"no");
  printf("  Selfroute %s\n",r.flags&ZEBRA_FLAG_SELFROUTE?"yes":"no");
  printf("  Blackhole %s\n",r.flags&ZEBRA_FLAG_BLACKHOLE?"yes":"no");
  printf("  IBGP: %s\n",r.flags&ZEBRA_FLAG_IBGP?"yes":"no");
  printf("  Selected: %s\n",r.flags&ZEBRA_FLAG_SELECTED?"yes":"no");
  printf("  Changed: %s\n",r.flags&ZEBRA_FLAG_CHANGED?"yes":"no");
  printf("  static: %s\n",r.flags&ZEBRA_FLAG_STATIC?"yes":"no");
  printf("  reject: %s\n",r.flags&ZEBRA_FLAG_REJECT?"yes":"no");
  puts("message:");
  printf("  nexthop: %s\n",r.message&ZAPI_MESSAGE_NEXTHOP?"yes":"no");
  printf("  ifindex: %s\n",r.message&ZAPI_MESSAGE_IFINDEX?"yes":"no");
  printf("  distance: %s\n",r.message&ZAPI_MESSAGE_DISTANCE?"yes":"no");
  printf("  metric: %s\n",r.message&ZAPI_MESSAGE_METRIC?"yes":"no");
  printf("Prefixlen: %d\n", r.prefixlen);
  printf("Prefix: %d", (unsigned char)r.prefix);
  c = (char*) &r.prefix;
  while (++i < (r.prefixlen/8 + (r.prefixlen % 8 ? 1 : 0)))
    printf(".%d",(unsigned char)*(c + i));
  while (i++ < 4)
    printf(".0");
  puts("");
  i=0;
  if (r.message&ZAPI_MESSAGE_NEXTHOP) {
    
    printf("nexthop-count: %d\n", r.nh_count);
    while (i++ < r.nh_count) {
      c = (unsigned char*) &r.nexthops[i];
      printf ("Nexthop %d: %d", i, (unsigned char) *c);
      while (++x < 4) {
	printf (".%d", (unsigned char) c[x]);
      }
      puts("");
    }
    i=0;
  }
  if (r.message&ZAPI_MESSAGE_IFINDEX) {
    
    printf("index-number: %d\n", r.ind_num);
    while (i++ < r.ind_num)
      printf("Index: %d: %d\n", i, r.index[i]);
    i=0;
    if (r.message&ZAPI_MESSAGE_DISTANCE)
      printf("Distance: %d\n",r.distance);
    if (r.message&ZAPI_MESSAGE_METRIC)
      printf("Metric: %d\n",r.metric);
    puts("\n");
  }
}
#endif

void *my_realloc (void *buf, size_t s, const char *c) {
  buf = realloc (buf, s);
  if (!buf) {
#ifdef OLSR_PLUGIN
    OLSR_PRINTF (1, "OUT OF MEMORY: %s\n", strerror(errno));
    olsr_syslog(OLSR_LOG_ERR, "olsrd: out of memory!: %m\n");
    olsr_exit(c, EXIT_FAILURE);
#else
    exit (EXIT_FAILURE);
#endif
  }
  return buf;
}


#ifndef OLSR_PLUGIN 
void *olsr_malloc (size_t f, const char *c) {
  void* v = malloc (f);
  return v;
}
#endif

/* Connect to the zebra-daemon, returns a socket */
int init_zebra () {
  struct sockaddr_in i;
  int ret;

  zsock = socket (AF_INET,SOCK_STREAM, 0);
  if (zsock <0 ) // TODO: Could not create socket
    return -1;
  memset (&i, 0, sizeof i);
  i.sin_family = AF_INET;
  i.sin_port = htons (ZEBRA_PORT);
  //  i.sin_len = sizeof i;
  i.sin_addr.s_addr = htonl (INADDR_LOOPBACK);
  
  ret = connect (zsock, (struct sockaddr *)&i, sizeof i);
  if  (ret < 0) {
    close (zsock);
    return -1;
  }
  status |= STATUS_CONNECTED;
  return zsock;
}

    
/* Sends a command to zebra, command is 
   the command defined in zebra.h, options is the packet-payload, 
   optlen the length, of the payload */
char zebra_send_command (unsigned char command, char * options, int optlen) {

  char *p = olsr_malloc (optlen+3, "zebra send_command");
  uint16_t length = optlen + 3;  // length of option + command + packet_length
  
  int ret;
  
  uint16_t len = htons(length);
  memcpy (p, &len, 2);
  p[2] = command;
  memcpy (p + 3, options, optlen);
  
  do {
    ret = write (zsock, p, length);
    if (ret < 0) {
      if (errno == EINTR) continue;
    }
    else return -1;
    p = p+ret;
  } while ((length =- ret));

  return 0;
}


/* Creates a Route-Packet-Payload, needs address, netmask, nexthop, 
   distance, and a pointer of an size_t */
static char* zebra_route_packet (struct ipv4_route r, ssize_t *optlen) {

  char *cmdopt, *t;
  *optlen = 9; // first: type, flags, message, prefixlen, nexthop number, nexthop)
  *optlen += r.prefixlen / 8 + (r.prefixlen % 8 ? 1 : 0);
  
  cmdopt = olsr_malloc (*optlen, "zebra add_v4_route");
  t = cmdopt;
  *t++ = 10; // Type: olsr
  *t++ = r.flags; // flags
  *t++ = r.message; // message: contains nexthop
  *t++ = r.prefixlen;
  memcpy (t, &r.prefix, r.prefixlen/8 + (r.prefixlen % 8 ? 1 : 0));
  *t += r.prefixlen/8 + (r.prefixlen % 8 ? 1 : 0);
  *t++ = r.nh_count;
  memcpy (t, r.nexthops, r.nh_count * sizeof *r.nexthops);
  return cmdopt;
}


/* adds a route to zebra-daemon (needs socket from zebra,
   address = prefix of the route
   mask = netmask of the route
   nexthop = nexthop of the route
   distance = distance-value of the route
*/
int zebra_add_v4_route (struct ipv4_route r) {
  
  char *cmdopt;
  ssize_t optlen;

  cmdopt = zebra_route_packet (r, &optlen);

  puts ("DEBUG: zebra_route_packet returned");
  
  

  return zebra_send_command (ZEBRA_IPV4_ROUTE_ADD, cmdopt, optlen);

}

/* deletes a route from the zebra-daemon (
   needs socket from zebra,
   address = prefix of the route
   mask = netmask of the route
   nexthop = nexthop of the route
   distance = distance-value of the route
*/
int zebra_delete_v4_route (struct ipv4_route r) {
  
  char *cmdopt;
  ssize_t optlen;
  
  cmdopt = zebra_route_packet (r, &optlen);
  
  return zebra_send_command (ZEBRA_IPV4_ROUTE_DELETE, cmdopt, optlen);

}


/* Check wether there is data from zebra aviable */
void zebra_check (void* foo) {
  char *data, *f;
  ssize_t len, ret;

  if (!status & STATUS_CONNECTED) {
  }
  data = try_read (&len);
  if (data) {
    f = data;
    do {
      ret = zebra_parse_packet (f, len);
      if (!ret) {//something wired happened
	puts ("DEBUG: IIIIIIIIIIRGS");
	exit (EXIT_FAILURE);
      }
      f += ret;
    } while ((f - data) < len);
    free (data);
  }
}


// tries to read a packet from zebra_socket
// if there is something to read - make sure to read whole packages
static char *try_read (ssize_t *len) {
  char *buf = NULL;
  ssize_t ret = 0, bsize = 0;
  uint16_t length = 0, l = 0;
  int sockstate;

  *len = 0;

  sockstate = fcntl (zsock, F_GETFL, 0);
  fcntl (zsock, F_SETFL, sockstate|O_NONBLOCK);

  do { 
    if (*len == bsize) {
      bsize += BUFSIZE;
      buf = my_realloc (buf, bsize, "Zebra try_read");
    }
    ret = read (zsock, buf + l, bsize - l);
    if (ret <= 0) {
      if (errno == EAGAIN) {
	errno = 0;
      }
      else {
	// TODO: errorhandling
	;
      }
      free (buf);
      return NULL;
    }
    *len += ret;

    while ((*len - l) > length) {
      //      printf ("DEBUG: *len -l > length - %d - %d > %d\n", *len, l, length);
      l += length;
      memcpy (&length, buf + l, 2);
      length = ntohs (length);
    }
    //    printf ("DEBUG: *len, l, length: %d,%d,%d\n", *len, l, length);
    if (((*len) - l) == length) break; // GOT FULL PACKAGE!!
    if (*len < l) {
      //      printf ("DEBUG: *len, l, length: %d,%d,%d\n", *len, l, length);
      fcntl (zsock, F_SETFL, sockstate);
      continue;
    }
  } while (1);

  fcntl (zsock, F_SETFL, sockstate);
  return buf;
}


/* Parse a packet recived from zebra */
int zebra_parse_packet (char *packet, ssize_t maxlen) {

  /* Array of functions */
  int (*foo[ZEBRA_MESSAGE_MAX]) (char *, size_t) = {
    parse_interface_add,
    parse_interface_delete,
    parse_interface_address_add,
    parse_interface_address_delete,
    parse_interface_up,
    parse_interface_down,
    ipv4_route_add,
    ipv4_route_delete,
    parse_ipv6_route_add
  };
  
  puts ("DEBUG: zebra_parse_packet");
  uint16_t length;
  
  int ret;
  memcpy (&length, packet, 2);
  length = ntohs (length);
  
  if (maxlen < length) {