1 |
/* |
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* Copyright (c) 2005,2006 Christophe Fillot. |
3 |
* E-mail: cf@utc.fr |
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* |
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* Network Utility functions. |
6 |
*/ |
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|
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#define _GNU_SOURCE |
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#include <stdio.h> |
10 |
#include <stdlib.h> |
11 |
#include <string.h> |
12 |
#include <stdarg.h> |
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#include <unistd.h> |
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#include <time.h> |
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#include <sys/time.h> |
16 |
#include <sys/ioctl.h> |
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#include <sys/types.h> |
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#include <sys/socket.h> |
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#include <arpa/inet.h> |
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#include <netdb.h> |
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#include <fcntl.h> |
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#include <errno.h> |
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#include <assert.h> |
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|
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#include "utils.h" |
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#include "net.h" |
27 |
#include "crc.h" |
28 |
|
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/* |
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* IP mask table, which allows to find quickly a network mask |
31 |
* with a prefix length. |
32 |
*/ |
33 |
n_ip_addr_t ip_masks[N_IP_ADDR_BITS+1] = { |
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0x0, |
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0x80000000, 0xC0000000, 0xE0000000, 0xF0000000, |
36 |
0xF8000000, 0xFC000000, 0xFE000000, 0xFF000000, |
37 |
0xFF800000, 0xFFC00000, 0xFFE00000, 0xFFF00000, |
38 |
0xFFF80000, 0xFFFC0000, 0xFFFE0000, 0xFFFF0000, |
39 |
0xFFFF8000, 0xFFFFC000, 0xFFFFE000, 0xFFFFF000, |
40 |
0xFFFFF800, 0xFFFFFC00, 0xFFFFFE00, 0xFFFFFF00, |
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0xFFFFFF80, 0xFFFFFFC0, 0xFFFFFFE0, 0xFFFFFFF0, |
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0xFFFFFFF8, 0xFFFFFFFC, 0xFFFFFFFE, 0xFFFFFFFF |
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}; |
44 |
|
45 |
/* |
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* IPv6 mask table, which allows to find quickly a network mask |
47 |
* with a prefix length. Note this is a particularly ugly way |
48 |
* to do this, since we use statically 2 Kb. |
49 |
*/ |
50 |
n_ipv6_addr_t ipv6_masks[N_IPV6_ADDR_BITS+1]; |
51 |
|
52 |
/* Initialize IPv6 masks */ |
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void ipv6_init_masks(void) |
54 |
{ |
55 |
int i,index; |
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|
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/* Set all bits to 1 */ |
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memset(ipv6_masks,0xff,sizeof(ipv6_masks)); |
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|
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for(i=0;i<N_IPV6_ADDR_BITS;i++) |
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{ |
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index = i >> 3; /* Compute byte index (divide by 8) */ |
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|
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/* rotate byte */ |
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ipv6_masks[i].ip6.u6_addr8[index++] <<= (8 - (i & 7)); |
66 |
|
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/* clear following bytes */ |
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while(index<N_IPV6_ADDR_LEN) |
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ipv6_masks[i].ip6.u6_addr8[index++] = 0; |
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} |
71 |
} |
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|
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/* Convert an IPv4 address into a string */ |
74 |
char *n_ip_ntoa(char *buffer,n_ip_addr_t ip_addr) |
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{ |
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u_char *p = (u_char *)&ip_addr; |
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sprintf(buffer,"%u.%u.%u.%u",p[0],p[1],p[2],p[3]); |
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return(buffer); |
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} |
80 |
|
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#if HAS_RFC2553 |
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/* Convert in IPv6 address into a string */ |
83 |
char *n_ipv6_ntoa(char *buffer,n_ipv6_addr_t *ipv6_addr) |
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{ |
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return((char *)inet_ntop(AF_INET6,ipv6_addr,buffer,INET6_ADDRSTRLEN)); |
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} |
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#endif |
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|
89 |
/* Convert a string containing an IP address in binary */ |
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int n_ip_aton(n_ip_addr_t *ip_addr,char *ip_str) |
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{ |
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struct in_addr addr; |
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|
94 |
if (inet_aton(ip_str,&addr) == 0) |
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return(-1); |
96 |
|
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*ip_addr = ntohl(addr.s_addr); |
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return(0); |
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} |
100 |
|
101 |
#if HAS_RFC2553 |
102 |
/* Convert an IPv6 address from string into binary */ |
103 |
int n_ipv6_aton(n_ipv6_addr_t *ipv6_addr,char *ip_str) |
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{ |
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return(inet_pton(AF_INET6,ip_str,ipv6_addr)); |
106 |
} |
107 |
#endif |
108 |
|
109 |
/* Parse an IPv4 CIDR prefix */ |
110 |
int ip_parse_cidr(char *token,n_ip_addr_t *net_addr,n_ip_addr_t *net_mask) |
111 |
{ |
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char *sl,*tmp,*err; |
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u_long mask; |
114 |
|
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/* Find separator */ |
116 |
if ((sl = strchr(token,'/')) == NULL) |
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return(-1); |
118 |
|
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/* Get mask */ |
120 |
mask = strtoul(sl+1,&err,0); |
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if (*err != 0) |
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return(-1); |
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|
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/* Ensure that mask has a correct value */ |
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if (mask > N_IP_ADDR_BITS) |
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return(-1); |
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|
128 |
if ((tmp = strdup(token)) == NULL) |
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return(-1); |
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|
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sl = strchr(tmp,'/'); |
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*sl = 0; |
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|
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/* Parse IP Address */ |
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if (n_ip_aton(net_addr,tmp) == -1) { |
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free(tmp); |
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return(-1); |
138 |
} |
139 |
|
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/* Set netmask */ |
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*net_mask = ip_masks[mask]; |
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|
143 |
free(tmp); |
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return(0); |
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} |
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|
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#if HAS_RFC2553 |
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/* Parse an IPv6 CIDR prefix */ |
149 |
int ipv6_parse_cidr(char *token,n_ipv6_addr_t *net_addr,u_int *net_mask) |
150 |
{ |
151 |
char *sl,*tmp,*err; |
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u_long mask; |
153 |
|
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/* Find separator */ |
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if ((sl = strchr(token,'/')) == NULL) |
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return(-1); |
157 |
|
158 |
/* Get mask */ |
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mask = strtoul(sl+1,&err,0); |
160 |
if (*err != 0) |
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return(-1); |
162 |
|
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/* Ensure that mask has a correct value */ |
164 |
if (mask > N_IPV6_ADDR_BITS) |
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return(-1); |
166 |
|
167 |
if ((tmp = strdup(token)) == NULL) |
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return(-1); |
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|
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sl = strchr(tmp,'/'); |
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*sl = 0; |
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|
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/* Parse IP Address */ |
174 |
if (n_ipv6_aton(net_addr,tmp) <= 0) { |
175 |
free(tmp); |
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return(-1); |
177 |
} |
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|
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/* Set netmask */ |
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*net_mask = (u_int)mask; |
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|
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free(tmp); |
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return(0); |
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} |
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#endif |
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|
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/* Parse a MAC address */ |
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int parse_mac_addr(n_eth_addr_t *addr,char *str) |
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{ |
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u_int v[N_ETH_ALEN]; |
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int i,res; |
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|
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/* First try, standard format (00:01:02:03:04:05) */ |
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res = sscanf(str,"%x:%x:%x:%x:%x:%x",&v[0],&v[1],&v[2],&v[3],&v[4],&v[5]); |
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|
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if (res == 6) { |
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for(i=0;i<N_ETH_ALEN;i++) |
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addr->eth_addr_byte[i] = v[i]; |
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return(0); |
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} |
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|
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/* Second try, Cisco format (0001.0002.0003) */ |
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res = sscanf(str,"%x.%x.%x",&v[0],&v[1],&v[2]); |
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|
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if (res == 3) { |
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addr->eth_addr_byte[0] = (v[0] >> 8) & 0xFF; |
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addr->eth_addr_byte[1] = v[0] & 0xFF; |
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addr->eth_addr_byte[2] = (v[1] >> 8) & 0xFF; |
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addr->eth_addr_byte[3] = v[1] & 0xFF; |
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addr->eth_addr_byte[4] = (v[2] >> 8) & 0xFF; |
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addr->eth_addr_byte[5] = v[2] & 0xFF; |
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} |
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|
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return(-1); |
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} |
216 |
|
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/* Convert an Ethernet address into a string */ |
218 |
char *n_eth_ntoa(char *buffer,n_eth_addr_t *addr,int format) |
219 |
{ |
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char *str_format; |
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|
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if (format == 0) { |
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str_format = "%2.2x:%2.2x:%2.2x:%2.2x:%2.2x:%2.2x"; |
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} else { |
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str_format = "%2.2x%2.2x.%2.2x%2.2x.%2.2x%2.2x"; |
226 |
} |
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|
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sprintf(buffer,str_format, |
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addr->eth_addr_byte[0],addr->eth_addr_byte[1], |
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addr->eth_addr_byte[2],addr->eth_addr_byte[3], |
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addr->eth_addr_byte[4],addr->eth_addr_byte[5]); |
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return(buffer); |
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} |
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|
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#if HAS_RFC2553 |
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/* Create a new socket to connect to specified host */ |
237 |
int udp_connect(int local_port,char *remote_host,int remote_port) |
238 |
{ |
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struct addrinfo hints,*res,*res0; |
240 |
struct sockaddr_storage st; |
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int error, sck = -1; |
242 |
char port_str[20]; |
243 |
|
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memset(&hints,0,sizeof(hints)); |
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hints.ai_family = PF_UNSPEC; |
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hints.ai_socktype = SOCK_DGRAM; |
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|
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snprintf(port_str,sizeof(port_str),"%d",remote_port); |
249 |
|
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if ((error = getaddrinfo(remote_host,port_str,&hints,&res0)) != 0) { |
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fprintf(stderr,"%s\n",gai_strerror(error)); |
252 |
return(-1); |
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} |
254 |
|
255 |
for(res=res0;res;res=res->ai_next) |
256 |
{ |
257 |
/* We want only IPv4 or IPv6 */ |
258 |
if ((res->ai_family != PF_INET) && (res->ai_family != PF_INET6)) |
259 |
continue; |
260 |
|
261 |
/* create new socket */ |
262 |
if ((sck = socket(res->ai_family,SOCK_DGRAM,res->ai_protocol)) < 0) { |
263 |
perror("udp_connect: socket"); |
264 |
continue; |
265 |
} |
266 |
|
267 |
/* bind to the local port */ |
268 |
memset(&st,0,sizeof(st)); |
269 |
|
270 |
switch(res->ai_family) { |
271 |
case PF_INET: { |
272 |
struct sockaddr_in *sin = (struct sockaddr_in *)&st; |
273 |
sin->sin_family = PF_INET; |
274 |
sin->sin_port = htons(local_port); |
275 |
break; |
276 |
} |
277 |
|
278 |
case PF_INET6: { |
279 |
struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)&st; |
280 |
#ifdef SIN6_LEN |
281 |
sin6->sin6_len = res->ai_addrlen; |
282 |
#endif |
283 |
sin6->sin6_family = PF_INET6; |
284 |
sin6->sin6_port = htons(local_port); |
285 |
break; |
286 |
} |
287 |
|
288 |
default: |
289 |
/* shouldn't happen */ |
290 |
close(sck); |
291 |
sck = -1; |
292 |
continue; |
293 |
} |
294 |
|
295 |
/* try to connect to remote host */ |
296 |
if (!bind(sck,(struct sockaddr *)&st,res->ai_addrlen) && |
297 |
!connect(sck,res->ai_addr,res->ai_addrlen)) |
298 |
break; |
299 |
|
300 |
close(sck); |
301 |
sck = -1; |
302 |
} |
303 |
|
304 |
freeaddrinfo(res0); |
305 |
return(sck); |
306 |
} |
307 |
#else |
308 |
/* |
309 |
* Create a new socket to connect to specified host. |
310 |
* Version for old systems that do not support RFC 2553 (getaddrinfo()) |
311 |
* |
312 |
* See http://www.faqs.org/rfcs/rfc2553.html for more info. |
313 |
*/ |
314 |
int udp_connect(int local_port,char *remote_host,int remote_port) |
315 |
{ |
316 |
struct sockaddr_in sin; |
317 |
struct hostent *hp; |
318 |
int sck; |
319 |
|
320 |
if (!(hp = gethostbyname(remote_host))) { |
321 |
fprintf(stderr,"udp_connect: unable to resolve '%s'\n",remote_host); |
322 |
return(-1); |
323 |
} |
324 |
|
325 |
if ((sck = socket(AF_INET,SOCK_DGRAM,0)) < 0) { |
326 |
perror("udp_connect: socket"); |
327 |
return(-1); |
328 |
} |
329 |
|
330 |
/* bind local port */ |
331 |
memset(&sin,0,sizeof(sin)); |
332 |
sin.sin_family = PF_INET; |
333 |
sin.sin_port = htons(local_port); |
334 |
|
335 |
if (bind(sck,(struct sockaddr *)&sin,sizeof(sin)) < 0) { |
336 |
perror("udp_connect: bind"); |
337 |
close(sck); |
338 |
} |
339 |
|
340 |
/* try to connect to remote host */ |
341 |
memset(&sin,0,sizeof(sin)); |
342 |
memcpy(&sin.sin_addr,hp->h_addr_list[0],sizeof(struct in_addr)); |
343 |
sin.sin_family = PF_INET; |
344 |
sin.sin_port = htons(remote_port); |
345 |
|
346 |
if (connect(sck,(struct sockaddr *)&sin,sizeof(sin)) < 0) { |
347 |
perror("udp_connect: connect"); |
348 |
close(sck); |
349 |
} |
350 |
|
351 |
return(sck); |
352 |
} |
353 |
#endif /* HAS_RFC2553 */ |
354 |
|
355 |
#if HAS_RFC2553 |
356 |
/* Listen on the specified port */ |
357 |
int ip_listen(char *ip_addr,int port,int sock_type,int max_fd,int fd_array[]) |
358 |
{ |
359 |
struct addrinfo hints,*res,*res0; |
360 |
char port_str[20],*addr; |
361 |
int nsock,error,i; |
362 |
int reuse = 1; |
363 |
|
364 |
for(i=0;i<max_fd;i++) |
365 |
fd_array[i] = -1; |
366 |
|
367 |
memset(&hints,0,sizeof(hints)); |
368 |
hints.ai_family = PF_UNSPEC; |
369 |
hints.ai_socktype = sock_type; |
370 |
hints.ai_flags = AI_PASSIVE; |
371 |
|
372 |
snprintf(port_str,sizeof(port_str),"%d",port); |
373 |
addr = (ip_addr && strlen(ip_addr)) ? ip_addr : NULL; |
374 |
|
375 |
if ((error = getaddrinfo(addr,port_str,&hints,&res0)) != 0) { |
376 |
fprintf(stderr,"ip_listen: %s", gai_strerror(error)); |
377 |
return(-1); |
378 |
} |
379 |
|
380 |
nsock = 0; |
381 |
for(res=res0;(res && (nsock < max_fd));res=res->ai_next) |
382 |
{ |
383 |
if ((res->ai_family != PF_INET) && (res->ai_family != PF_INET6)) |
384 |
continue; |
385 |
|
386 |
fd_array[nsock] = socket(res->ai_family,res->ai_socktype, |
387 |
res->ai_protocol); |
388 |
|
389 |
if (fd_array[nsock] < 0) |
390 |
continue; |
391 |
|
392 |
setsockopt(fd_array[nsock],SOL_SOCKET,SO_REUSEADDR,&reuse,sizeof(reuse)); |
393 |
|
394 |
if ((bind(fd_array[nsock],res->ai_addr,res->ai_addrlen) < 0) || |
395 |
((sock_type == SOCK_STREAM) && (listen(fd_array[nsock],5) < 0))) |
396 |
{ |
397 |
close(fd_array[nsock]); |
398 |
fd_array[nsock] = -1; |
399 |
continue; |
400 |
} |
401 |
|
402 |
nsock++; |
403 |
} |
404 |
|
405 |
freeaddrinfo(res0); |
406 |
return(nsock); |
407 |
} |
408 |
#else |
409 |
/* Listen on the specified port */ |
410 |
int ip_listen(char *ip_addr,int port,int sock_type,int max_fd,int fd_array[]) |
411 |
{ |
412 |
struct sockaddr_in sin; |
413 |
int i,sck,reuse=1; |
414 |
|
415 |
for(i=0;i<max_fd;i++) |
416 |
fd_array[i] = -1; |
417 |
|
418 |
if ((sck = socket(AF_INET,sock_type,0)) < 0) { |
419 |
perror("ip_listen: socket"); |
420 |
return(-1); |
421 |
} |
422 |
|
423 |
/* bind local port */ |
424 |
memset(&sin,0,sizeof(sin)); |
425 |
sin.sin_family = PF_INET; |
426 |
sin.sin_port = htons(port); |
427 |
|
428 |
if (ip_addr && strlen(ip_addr)) |
429 |
sin.sin_addr.s_addr = inet_addr(ip_addr); |
430 |
|
431 |
setsockopt(fd_array[0],SOL_SOCKET,SO_REUSEADDR,&reuse,sizeof(reuse)); |
432 |
|
433 |
if (bind(sck,(struct sockaddr *)&sin,sizeof(sin)) < 0) { |
434 |
perror("ip_listen: bind"); |
435 |
goto error; |
436 |
} |
437 |
|
438 |
if ((sock_type == SOCK_STREAM) && (listen(sck,5) < 0)) { |
439 |
perror("ip_listen: listen"); |
440 |
goto error; |
441 |
} |
442 |
|
443 |
fd_array[0] = sck; |
444 |
return(1); |
445 |
|
446 |
error: |
447 |
close(sck); |
448 |
return(-1); |
449 |
} |
450 |
#endif |
451 |
|
452 |
/* |
453 |
* ISL rewrite. |
454 |
* |
455 |
* See: http://www.cisco.com/en/US/tech/tk389/tk390/technologies_tech_note09186a0080094665.shtml |
456 |
*/ |
457 |
void cisco_isl_rewrite(m_uint8_t *pkt,m_uint32_t tot_len) |
458 |
{ |
459 |
static m_uint8_t isl_xaddr[N_ETH_ALEN] = { 0x01,0x00,0x0c,0x00,0x10,0x00 }; |
460 |
u_int real_offset,real_len; |
461 |
n_eth_hdr_t *hdr; |
462 |
m_uint32_t ifcs; |
463 |
|
464 |
hdr = (n_eth_hdr_t *)pkt; |
465 |
if (!memcmp(&hdr->daddr,isl_xaddr,N_ETH_ALEN)) { |
466 |
real_offset = N_ETH_HLEN + N_ISL_HDR_SIZE; |
467 |
real_len = ntohs(hdr->type); |
468 |
real_len -= (N_ISL_HDR_SIZE + 4); |
469 |
|
470 |
if ((real_offset+real_len) > tot_len) |
471 |
return; |
472 |
|
473 |
/* Rewrite the destination MAC address */ |
474 |
hdr->daddr.eth_addr_byte[4] = 0x00; |
475 |
|
476 |
/* Compute the internal FCS on the encapsulated packet */ |
477 |
ifcs = crc32_compute(0xFFFFFFFF,pkt+real_offset,real_len); |
478 |
pkt[tot_len-4] = ifcs & 0xff; |
479 |
pkt[tot_len-3] = (ifcs >> 8) & 0xff; |
480 |
pkt[tot_len-2] = (ifcs >> 16) & 0xff; |
481 |
pkt[tot_len-1] = ifcs >> 24; |
482 |
} |
483 |
} |