tinc/src/netutl.c
2019-08-26 13:44:49 +02:00

347 lines
7.1 KiB
C

/*
netutl.c -- some supporting network utility code
Copyright (C) 1998-2005 Ivo Timmermans
2000-2016 Guus Sliepen <guus@tinc-vpn.org>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License along
with this program; if not, write to the Free Software Foundation, Inc.,
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include "system.h"
#include "net.h"
#include "netutl.h"
#include "logger.h"
#include "utils.h"
#include "xalloc.h"
bool hostnames = false;
/*
Turn a string into a struct addrinfo.
Return NULL on failure.
*/
struct addrinfo *str2addrinfo(const char *address, const char *service, int socktype) {
struct addrinfo *ai = NULL, hint = {0};
int err;
hint.ai_family = addressfamily;
hint.ai_socktype = socktype;
#if HAVE_DECL_RES_INIT
// ensure glibc reloads /etc/resolv.conf.
res_init();
#endif
err = getaddrinfo(address, service, &hint, &ai);
if(err) {
logger(LOG_WARNING, "Error looking up %s port %s: %s", address,
service, gai_strerror(err));
return NULL;
}
return ai;
}
sockaddr_t str2sockaddr(const char *address, const char *port) {
struct addrinfo *ai = NULL, hint = {0};
sockaddr_t result;
int err;
hint.ai_family = AF_UNSPEC;
hint.ai_flags = AI_NUMERICHOST;
hint.ai_socktype = SOCK_STREAM;
err = getaddrinfo(address, port, &hint, &ai);
if(err || !ai) {
ifdebug(SCARY_THINGS)
logger(LOG_DEBUG, "Unknown type address %s port %s", address, port);
result.sa.sa_family = AF_UNKNOWN;
result.unknown.address = xstrdup(address);
result.unknown.port = xstrdup(port);
return result;
}
memcpy(&result, ai->ai_addr, ai->ai_addrlen);
freeaddrinfo(ai);
return result;
}
void sockaddr2str(const sockaddr_t *sa, char **addrstr, char **portstr) {
char address[NI_MAXHOST];
char port[NI_MAXSERV];
char *scopeid;
int err;
if(sa->sa.sa_family == AF_UNKNOWN) {
if(addrstr) {
*addrstr = xstrdup(sa->unknown.address);
}
if(portstr) {
*portstr = xstrdup(sa->unknown.port);
}
return;
}
err = getnameinfo(&sa->sa, SALEN(sa->sa), address, sizeof(address), port, sizeof(port), NI_NUMERICHOST | NI_NUMERICSERV);
if(err) {
logger(LOG_ERR, "Error while translating addresses: %s",
gai_strerror(err));
abort();
}
scopeid = strchr(address, '%');
if(scopeid) {
*scopeid = '\0'; /* Descope. */
}
if(addrstr) {
*addrstr = xstrdup(address);
}
if(portstr) {
*portstr = xstrdup(port);
}
}
char *sockaddr2hostname(const sockaddr_t *sa) {
char *str;
char address[NI_MAXHOST] = "unknown";
char port[NI_MAXSERV] = "unknown";
int err;
if(sa->sa.sa_family == AF_UNKNOWN) {
xasprintf(&str, "%s port %s", sa->unknown.address, sa->unknown.port);
return str;
}
err = getnameinfo(&sa->sa, SALEN(sa->sa), address, sizeof(address), port, sizeof(port),
hostnames ? 0 : (NI_NUMERICHOST | NI_NUMERICSERV));
if(err) {
logger(LOG_ERR, "Error while looking up hostname: %s",
gai_strerror(err));
}
xasprintf(&str, "%s port %s", address, port);
return str;
}
int sockaddrcmp_noport(const sockaddr_t *a, const sockaddr_t *b) {
int result;
result = a->sa.sa_family - b->sa.sa_family;
if(result) {
return result;
}
switch(a->sa.sa_family) {
case AF_UNSPEC:
return 0;
case AF_UNKNOWN:
return strcmp(a->unknown.address, b->unknown.address);
case AF_INET:
return memcmp(&a->in.sin_addr, &b->in.sin_addr, sizeof(a->in.sin_addr));
case AF_INET6:
return memcmp(&a->in6.sin6_addr, &b->in6.sin6_addr, sizeof(a->in6.sin6_addr));
default:
logger(LOG_ERR, "sockaddrcmp() was called with unknown address family %d, exitting!",
a->sa.sa_family);
abort();
}
}
int sockaddrcmp(const sockaddr_t *a, const sockaddr_t *b) {
int result;
result = a->sa.sa_family - b->sa.sa_family;
if(result) {
return result;
}
switch(a->sa.sa_family) {
case AF_UNSPEC:
return 0;
case AF_UNKNOWN:
result = strcmp(a->unknown.address, b->unknown.address);
if(result) {
return result;
}
return strcmp(a->unknown.port, b->unknown.port);
case AF_INET:
result = memcmp(&a->in.sin_addr, &b->in.sin_addr, sizeof(a->in.sin_addr));
if(result) {
return result;
}
return memcmp(&a->in.sin_port, &b->in.sin_port, sizeof(a->in.sin_port));
case AF_INET6:
result = memcmp(&a->in6.sin6_addr, &b->in6.sin6_addr, sizeof(a->in6.sin6_addr));
if(result) {
return result;
}
return memcmp(&a->in6.sin6_port, &b->in6.sin6_port, sizeof(a->in6.sin6_port));
default:
logger(LOG_ERR, "sockaddrcmp() was called with unknown address family %d, exitting!",
a->sa.sa_family);
abort();
}
}
void sockaddrcpy(sockaddr_t *a, const sockaddr_t *b) {
if(b->sa.sa_family != AF_UNKNOWN) {
*a = *b;
} else {
a->unknown.family = AF_UNKNOWN;
a->unknown.address = xstrdup(b->unknown.address);
a->unknown.port = xstrdup(b->unknown.port);
}
}
void sockaddrfree(sockaddr_t *a) {
if(a->sa.sa_family == AF_UNKNOWN) {
free(a->unknown.address);
free(a->unknown.port);
}
}
void sockaddrunmap(sockaddr_t *sa) {
if(sa->sa.sa_family == AF_INET6 && IN6_IS_ADDR_V4MAPPED(&sa->in6.sin6_addr)) {
sa->in.sin_addr.s_addr = ((uint32_t *) & sa->in6.sin6_addr)[3];
sa->in.sin_family = AF_INET;
}
}
void sockaddr_setport(sockaddr_t *sa, const char *port) {
uint16_t portnum = htons(atoi(port));
if(!portnum) {
return;
}
switch(sa->sa.sa_family) {
case AF_INET:
sa->in.sin_port = portnum;
break;
case AF_INET6:
sa->in6.sin6_port = portnum;
break;
case AF_UNKNOWN:
free(sa->unknown.port);
sa->unknown.port = xstrdup(port);
default:
return;
}
}
/* Subnet mask handling */
int maskcmp(const void *va, const void *vb, int masklen) {
int i, m, result;
const char *a = va;
const char *b = vb;
for(m = masklen, i = 0; m >= 8; m -= 8, i++) {
result = a[i] - b[i];
if(result) {
return result;
}
}
if(m)
return (a[i] & (0x100 - (1 << (8 - m)))) -
(b[i] & (0x100 - (1 << (8 - m))));
return 0;
}
void mask(void *va, int masklen, int len) {
int i;
char *a = va;
i = masklen / 8;
masklen %= 8;
if(masklen) {
a[i++] &= (0x100 - (1 << (8 - masklen)));
}
for(; i < len; i++) {
a[i] = 0;
}
}
void maskcpy(void *va, const void *vb, int masklen, int len) {
int i, m;
char *a = va;
const char *b = vb;
for(m = masklen, i = 0; m >= 8; m -= 8, i++) {
a[i] = b[i];
}
if(m) {
a[i] = b[i] & (0x100 - (1 << (8 - m)));
i++;
}
for(; i < len; i++) {
a[i] = 0;
}
}
bool maskcheck(const void *va, int masklen, int len) {
int i;
const char *a = va;
i = masklen / 8;
masklen %= 8;
if(masklen && a[i++] & (0xff >> masklen)) {
return false;
}
for(; i < len; i++)
if(a[i] != 0) {
return false;
}
return true;
}