| 1 |
/* |
| 2 |
* Copyright (c) 2005,2006 Christophe Fillot. |
| 3 |
* E-mail: cf@utc.fr |
| 4 |
* |
| 5 |
* Network Utility functions. |
| 6 |
*/ |
| 7 |
|
| 8 |
#define _GNU_SOURCE |
| 9 |
#include <stdio.h> |
| 10 |
#include <stdlib.h> |
| 11 |
#include <string.h> |
| 12 |
#include <stdarg.h> |
| 13 |
#include <unistd.h> |
| 14 |
#include <time.h> |
| 15 |
#include <sys/time.h> |
| 16 |
#include <sys/ioctl.h> |
| 17 |
#include <sys/types.h> |
| 18 |
#include <sys/socket.h> |
| 19 |
#include <arpa/inet.h> |
| 20 |
#include <netdb.h> |
| 21 |
#include <fcntl.h> |
| 22 |
#include <errno.h> |
| 23 |
#include <assert.h> |
| 24 |
|
| 25 |
#include "utils.h" |
| 26 |
#include "net.h" |
| 27 |
#include "crc.h" |
| 28 |
|
| 29 |
/* |
| 30 |
* 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] = { |
| 34 |
0x0, |
| 35 |
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, |
| 41 |
0xFFFFFF80, 0xFFFFFFC0, 0xFFFFFFE0, 0xFFFFFFF0, |
| 42 |
0xFFFFFFF8, 0xFFFFFFFC, 0xFFFFFFFE, 0xFFFFFFFF |
| 43 |
}; |
| 44 |
|
| 45 |
/* |
| 46 |
* 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 */ |
| 53 |
void ipv6_init_masks(void) |
| 54 |
{ |
| 55 |
int i,index; |
| 56 |
|
| 57 |
/* Set all bits to 1 */ |
| 58 |
memset(ipv6_masks,0xff,sizeof(ipv6_masks)); |
| 59 |
|
| 60 |
for(i=0;i<N_IPV6_ADDR_BITS;i++) |
| 61 |
{ |
| 62 |
index = i >> 3; /* Compute byte index (divide by 8) */ |
| 63 |
|
| 64 |
/* rotate byte */ |
| 65 |
ipv6_masks[i].ip6.u6_addr8[index++] <<= (8 - (i & 7)); |
| 66 |
|
| 67 |
/* clear following bytes */ |
| 68 |
while(index<N_IPV6_ADDR_LEN) |
| 69 |
ipv6_masks[i].ip6.u6_addr8[index++] = 0; |
| 70 |
} |
| 71 |
} |
| 72 |
|
| 73 |
/* Convert an IPv4 address into a string */ |
| 74 |
char *n_ip_ntoa(char *buffer,n_ip_addr_t ip_addr) |
| 75 |
{ |
| 76 |
u_char *p = (u_char *)&ip_addr; |
| 77 |
sprintf(buffer,"%u.%u.%u.%u",p[0],p[1],p[2],p[3]); |
| 78 |
return(buffer); |
| 79 |
} |
| 80 |
|
| 81 |
#if HAS_RFC2553 |
| 82 |
/* Convert in IPv6 address into a string */ |
| 83 |
char *n_ipv6_ntoa(char *buffer,n_ipv6_addr_t *ipv6_addr) |
| 84 |
{ |
| 85 |
return((char *)inet_ntop(AF_INET6,ipv6_addr,buffer,INET6_ADDRSTRLEN)); |
| 86 |
} |
| 87 |
#endif |
| 88 |
|
| 89 |
/* Convert a string containing an IP address in binary */ |
| 90 |
int n_ip_aton(n_ip_addr_t *ip_addr,char *ip_str) |
| 91 |
{ |
| 92 |
struct in_addr addr; |
| 93 |
|
| 94 |
if (inet_aton(ip_str,&addr) == 0) |
| 95 |
return(-1); |
| 96 |
|
| 97 |
*ip_addr = ntohl(addr.s_addr); |
| 98 |
return(0); |
| 99 |
} |
| 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) |
| 104 |
{ |
| 105 |
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 |
{ |
| 112 |
char *sl,*tmp,*err; |
| 113 |
u_long mask; |
| 114 |
|
| 115 |
/* Find separator */ |
| 116 |
if ((sl = strchr(token,'/')) == NULL) |
| 117 |
return(-1); |
| 118 |
|
| 119 |
/* Get mask */ |
| 120 |
mask = strtoul(sl+1,&err,0); |
| 121 |
if (*err != 0) |
| 122 |
return(-1); |
| 123 |
|
| 124 |
/* Ensure that mask has a correct value */ |
| 125 |
if (mask > N_IP_ADDR_BITS) |
| 126 |
return(-1); |
| 127 |
|
| 128 |
if ((tmp = strdup(token)) == NULL) |
| 129 |
return(-1); |
| 130 |
|
| 131 |
sl = strchr(tmp,'/'); |
| 132 |
*sl = 0; |
| 133 |
|
| 134 |
/* Parse IP Address */ |
| 135 |
if (n_ip_aton(net_addr,tmp) == -1) { |
| 136 |
free(tmp); |
| 137 |
return(-1); |
| 138 |
} |
| 139 |
|
| 140 |
/* Set netmask */ |
| 141 |
*net_mask = ip_masks[mask]; |
| 142 |
|
| 143 |
free(tmp); |
| 144 |
return(0); |
| 145 |
} |
| 146 |
|
| 147 |
#if HAS_RFC2553 |
| 148 |
/* 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; |
| 152 |
u_long mask; |
| 153 |
|
| 154 |
/* Find separator */ |
| 155 |
if ((sl = strchr(token,'/')) == NULL) |
| 156 |
return(-1); |
| 157 |
|
| 158 |
/* Get mask */ |
| 159 |
mask = strtoul(sl+1,&err,0); |
| 160 |
if (*err != 0) |
| 161 |
return(-1); |
| 162 |
|
| 163 |
/* Ensure that mask has a correct value */ |
| 164 |
if (mask > N_IPV6_ADDR_BITS) |
| 165 |
return(-1); |
| 166 |
|
| 167 |
if ((tmp = strdup(token)) == NULL) |
| 168 |
return(-1); |
| 169 |
|
| 170 |
sl = strchr(tmp,'/'); |
| 171 |
*sl = 0; |
| 172 |
|
| 173 |
/* Parse IP Address */ |
| 174 |
if (n_ipv6_aton(net_addr,tmp) <= 0) { |
| 175 |
free(tmp); |
| 176 |
return(-1); |
| 177 |
} |
| 178 |
|
| 179 |
/* Set netmask */ |
| 180 |
*net_mask = (u_int)mask; |
| 181 |
|
| 182 |
free(tmp); |
| 183 |
return(0); |
| 184 |
} |
| 185 |
#endif |
| 186 |
|
| 187 |
/* Parse a MAC address */ |
| 188 |
int parse_mac_addr(n_eth_addr_t *addr,char *str) |
| 189 |
{ |
| 190 |
u_int v[N_ETH_ALEN]; |
| 191 |
int i,res; |
| 192 |
|
| 193 |
/* First try, standard format (00:01:02:03:04:05) */ |
| 194 |
res = sscanf(str,"%x:%x:%x:%x:%x:%x",&v[0],&v[1],&v[2],&v[3],&v[4],&v[5]); |
| 195 |
|
| 196 |
if (res == 6) { |
| 197 |
for(i=0;i<N_ETH_ALEN;i++) |
| 198 |
addr->eth_addr_byte[i] = v[i]; |
| 199 |
return(0); |
| 200 |
} |
| 201 |
|
| 202 |
/* Second try, Cisco format (0001.0002.0003) */ |
| 203 |
res = sscanf(str,"%x.%x.%x",&v[0],&v[1],&v[2]); |
| 204 |
|
| 205 |
if (res == 3) { |
| 206 |
addr->eth_addr_byte[0] = (v[0] >> 8) & 0xFF; |
| 207 |
addr->eth_addr_byte[1] = v[0] & 0xFF; |
| 208 |
addr->eth_addr_byte[2] = (v[1] >> 8) & 0xFF; |
| 209 |
addr->eth_addr_byte[3] = v[1] & 0xFF; |
| 210 |
addr->eth_addr_byte[4] = (v[2] >> 8) & 0xFF; |
| 211 |
addr->eth_addr_byte[5] = v[2] & 0xFF; |
| 212 |
} |
| 213 |
|
| 214 |
return(-1); |
| 215 |
} |
| 216 |
|
| 217 |
/* Convert an Ethernet address into a string */ |
| 218 |
char *n_eth_ntoa(char *buffer,n_eth_addr_t *addr,int format) |
| 219 |
{ |
| 220 |
char *str_format; |
| 221 |
|
| 222 |
if (format == 0) { |
| 223 |
str_format = "%2.2x:%2.2x:%2.2x:%2.2x:%2.2x:%2.2x"; |
| 224 |
} else { |
| 225 |
str_format = "%2.2x%2.2x.%2.2x%2.2x.%2.2x%2.2x"; |
| 226 |
} |
| 227 |
|
| 228 |
sprintf(buffer,str_format, |
| 229 |
addr->eth_addr_byte[0],addr->eth_addr_byte[1], |
| 230 |
addr->eth_addr_byte[2],addr->eth_addr_byte[3], |
| 231 |
addr->eth_addr_byte[4],addr->eth_addr_byte[5]); |
| 232 |
return(buffer); |
| 233 |
} |
| 234 |
|
| 235 |
#if HAS_RFC2553 |
| 236 |
/* Create a new socket to connect to specified host */ |
| 237 |
int udp_connect(int local_port,char *remote_host,int remote_port) |
| 238 |
{ |
| 239 |
struct addrinfo hints,*res,*res0; |
| 240 |
struct sockaddr_storage st; |
| 241 |
int error, sck = -1; |
| 242 |
char port_str[20]; |
| 243 |
|
| 244 |
memset(&hints,0,sizeof(hints)); |
| 245 |
hints.ai_family = PF_UNSPEC; |
| 246 |
hints.ai_socktype = SOCK_DGRAM; |
| 247 |
|
| 248 |
snprintf(port_str,sizeof(port_str),"%d",remote_port); |
| 249 |
|
| 250 |
if ((error = getaddrinfo(remote_host,port_str,&hints,&res0)) != 0) { |
| 251 |
fprintf(stderr,"%s\n",gai_strerror(error)); |
| 252 |
return(-1); |
| 253 |
} |
| 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 |
} |
Parent Directory
| 
Revision Log