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/* vi: set sw=4 ts=4: */
/*
* Utility routines.
*
* Connect to host at port using address resolution from getaddrinfo
*
*/
#include <netinet/in.h>
#include "libbb.h"
static const int one = 1;
int setsockopt_reuseaddr(int fd)
{
return setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one));
}
int setsockopt_broadcast(int fd)
{
return setsockopt(fd, SOL_SOCKET, SO_BROADCAST, &one, sizeof(one));
}
void xconnect(int s, const struct sockaddr *s_addr, socklen_t addrlen)
{
if (connect(s, s_addr, addrlen) < 0) {
if (ENABLE_FEATURE_CLEAN_UP)
close(s);
if (s_addr->sa_family == AF_INET)
bb_perror_msg_and_die("%s (%s)",
"cannot connect to remote host",
inet_ntoa(((struct sockaddr_in *)s_addr)->sin_addr));
bb_perror_msg_and_die("cannot connect to remote host");
}
}
/* Return network byte ordered port number for a service.
* If "port" is a number use it as the port.
* If "port" is a name it is looked up in /etc/services, if it isnt found return
* default_port */
unsigned bb_lookup_port(const char *port, const char *protocol, unsigned default_port)
{
unsigned port_nr = htons(default_port);
if (port) {
int old_errno;
/* Since this is a lib function, we're not allowed to reset errno to 0.
* Doing so could break an app that is deferring checking of errno. */
old_errno = errno;
port_nr = bb_strtou(port, NULL, 10);
if (errno || port_nr > 65535) {
struct servent *tserv = getservbyname(port, protocol);
if (tserv)
port_nr = tserv->s_port;
} else {
port_nr = htons(port_nr);
}
errno = old_errno;
}
return port_nr;
}
/* "Old" networking API - only IPv4 */
void bb_lookup_host(struct sockaddr_in *s_in, const char *host)
{
struct hostent *he;
memset(s_in, 0, sizeof(struct sockaddr_in));
s_in->sin_family = AF_INET;
he = xgethostbyname(host);
memcpy(&(s_in->sin_addr), he->h_addr_list[0], he->h_length);
}
int xconnect_tcp_v4(struct sockaddr_in *s_addr)
{
int s = xsocket(AF_INET, SOCK_STREAM, 0);
xconnect(s, (struct sockaddr*) s_addr, sizeof(*s_addr));
return s;
}
/* "New" networking API */
//extern int xsocket_stream_ip4or6(sa_family_t *fp);
//extern len_and_sockaddr* dotted2sockaddr(const char *dotted, int def_port);
/* peer: "1.2.3.4[:port]", "www.google.com[:port]"
* port: if neither of above specifies port #
*/
static len_and_sockaddr* str2sockaddr(const char *host, int port, int ai_flags)
{
int rc;
len_and_sockaddr *r; // = NULL;
struct addrinfo *result = NULL;
const char *org_host = host; /* only for error msg */
const char *cp;
char service[sizeof(int)*3 + 1];
struct addrinfo hint;
/* Ugly parsing of host:addr */
if (ENABLE_FEATURE_IPV6 && host[0] == '[') {
host++;
cp = strchr(host, ']');
if (!cp || cp[1] != ':') /* Malformed: must have [xx]:nn */
bb_error_msg_and_die("bad address '%s'", org_host);
//return r; /* return NULL */
} else {
cp = strrchr(host, ':');
if (ENABLE_FEATURE_IPV6 && cp && strchr(host, ':') != cp) {
/* There is more than one ':' (e.g. "::1") */
cp = NULL; /* it's not a port spec */
}
}
if (cp) {
int sz = cp - host + 1;
host = safe_strncpy(alloca(sz), host, sz);
if (ENABLE_FEATURE_IPV6 && *cp != ':')
cp++; /* skip ']' */
cp++; /* skip ':' */
} else {
utoa_to_buf(port, service, sizeof(service));
cp = service;
}
memset(&hint, 0 , sizeof(hint));
/* hint.ai_family = AF_UNSPEC; - zero anyway */
#if !ENABLE_FEATURE_IPV6
hint.ai_family = AF_INET; /* do not try to find IPv6 */
#endif
/* Needed. Or else we will get each address thrice (or more)
* for each possible socket type (tcp,udp,raw...): */
hint.ai_socktype = SOCK_STREAM;
hint.ai_flags = ai_flags | AI_NUMERICSERV;
rc = getaddrinfo(host, cp, &hint, &result);
if (rc || !result)
bb_error_msg_and_die("bad address '%s'", org_host);
r = xmalloc(offsetof(len_and_sockaddr, sa) + result->ai_addrlen);
r->len = result->ai_addrlen;
memcpy(&r->sa, result->ai_addr, result->ai_addrlen);
freeaddrinfo(result);
return r;
}
len_and_sockaddr* host2sockaddr(const char *host, int port)
{
return str2sockaddr(host, port, 0);
}
static len_and_sockaddr* dotted2sockaddr(const char *host, int port)
{
return str2sockaddr(host, port, NI_NUMERICHOST);
}
static int xsocket_stream_ip4or6(len_and_sockaddr *lsa)
{
int fd;
#if ENABLE_FEATURE_IPV6
fd = socket(AF_INET6, SOCK_STREAM, 0);
lsa->sa.sa_family = AF_INET6;
lsa->len = sizeof(struct sockaddr_in6);
if (fd >= 0)
return fd;
#endif
fd = xsocket(AF_INET, SOCK_STREAM, 0);
lsa->sa.sa_family = AF_INET;
lsa->len = sizeof(struct sockaddr_in);
return fd;
}
int create_and_bind_stream_or_die(const char *bindaddr, int port)
{
int fd;
len_and_sockaddr *lsa;
if (bindaddr && bindaddr[0]) {
lsa = dotted2sockaddr(bindaddr, port);
/* currently NULL check is in str2sockaddr */
//if (!lsa)
// bb_error_msg_and_die("bad address '%s'", bindaddr);
/* user specified bind addr dictates family */
fd = xsocket(lsa->sa.sa_family, SOCK_STREAM, 0);
} else {
lsa = xzalloc(offsetof(len_and_sockaddr, sa) +
USE_FEATURE_IPV6(sizeof(struct sockaddr_in6))
SKIP_FEATURE_IPV6(sizeof(struct sockaddr_in))
);
fd = xsocket_stream_ip4or6(lsa);
}
setsockopt_reuseaddr(fd);
xbind(fd, &lsa->sa, lsa->len);
free(lsa);
return fd;
}
int create_and_connect_stream_or_die(const char *peer, int port)
{
int fd;
len_and_sockaddr *lsa;
lsa = host2sockaddr(peer, port);
/* currently NULL check is in str2sockaddr */
//if (!lsa)
// bb_error_msg_and_die("bad address '%s'", peer);
fd = xsocket(lsa->sa.sa_family, SOCK_STREAM, 0);
setsockopt_reuseaddr(fd);
xconnect(fd, &lsa->sa, lsa->len);
free(lsa);
return fd;
}
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