hush/libbb/xconnect.c
Denis Vlasenko 1dc1b37b33 use xbind, xconnect where appropriate.
small edits to arping
2006-12-23 02:48:44 +00:00

155 lines
3.8 KiB
C

/* vi: set sw=4 ts=4: */
/*
* Utility routines.
*
* Connect to host at port using address resolution from getaddrinfo
*
*/
#include "libbb.h"
/* 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 short bb_lookup_port(const char *port, const char *protocol, unsigned short default_port)
{
unsigned short port_nr = htons(default_port);
if (port) {
char *endptr;
int old_errno;
long port_long;
/* 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;
errno = 0;
port_long = strtol(port, &endptr, 10);
if (errno != 0 || *endptr!='\0' || endptr==port || port_long < 0 || port_long > 65535) {
struct servent *tserv = getservbyname(port, protocol);
if (tserv) {
port_nr = tserv->s_port;
}
} else {
port_nr = htons(port_long);
}
errno = old_errno;
}
return port_nr;
}
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);
}
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");
}
}
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;
}
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));
}
int dotted2sockaddr(const char *dotted, struct sockaddr* sp, int socklen)
{
union {
struct in_addr a4;
#if ENABLE_FEATURE_IPV6
struct in6_addr a6;
#endif
} a;
/* TODO maybe: port spec? like n.n.n.n:nn */
#if ENABLE_FEATURE_IPV6
if (socklen >= sizeof(struct sockaddr_in6)
&& inet_pton(AF_INET6, dotted, &a.a6) > 0
) {
((struct sockaddr_in6*)sp)->sin6_family = AF_INET6;
((struct sockaddr_in6*)sp)->sin6_addr = a.a6;
/* ((struct sockaddr_in6*)sp)->sin6_port = */
return 0; /* success */
}
#endif
if (socklen >= sizeof(struct sockaddr_in)
&& inet_pton(AF_INET, dotted, &a.a4) > 0
) {
((struct sockaddr_in*)sp)->sin_family = AF_INET;
((struct sockaddr_in*)sp)->sin_addr = a.a4;
/* ((struct sockaddr_in*)sp)->sin_port = */
return 0; /* success */
}
return 1;
}
int xsocket_stream_ip4or6(sa_family_t *fp)
{
int fd;
#if ENABLE_FEATURE_IPV6
fd = socket(AF_INET6, SOCK_STREAM, 0);
if (fp) *fp = AF_INET6;
if (fd < 0)
#endif
{
fd = xsocket(AF_INET, SOCK_STREAM, 0);
if (fp) *fp = AF_INET;
}
return fd;
}
int create_and_bind_socket_ip4or6(const char *hostaddr, int port)
{
int fd;
sockaddr_inet sa;
memset(&sa, 0, sizeof(sa));
if (hostaddr) {
if (dotted2sockaddr(hostaddr, &sa.sa, sizeof(sa)))
bb_error_msg_and_die("bad address '%s'", hostaddr);
/* user specified bind addr dictates family */
fd = xsocket(sa.sa.sa_family, SOCK_STREAM, 0);
} else
fd = xsocket_stream_ip4or6(&sa.sa.sa_family);
setsockopt_reuseaddr(fd);
/* if (port >= 0) { */
#if ENABLE_FEATURE_IPV6
if (sa.sa.sa_family == AF_INET6 /* && !sa.sin6.sin6_port */)
sa.sin6.sin6_port = htons(port);
#endif
if (sa.sa.sa_family == AF_INET /* && !sa.sin.sin_port */)
sa.sin.sin_port = htons(port);
/* } */
xbind(fd, &sa.sa, sizeof(sa));
return fd;
}