File: [local] / src / usr.bin / ssh / canohost.c (download)
Revision 1.74, Fri Jun 28 13:35:04 2019 UTC (4 years, 11 months ago) by deraadt
Branch: MAIN
CVS Tags: OPENBSD_6_8_BASE, OPENBSD_6_8, OPENBSD_6_7_BASE, OPENBSD_6_7, OPENBSD_6_6_BASE, OPENBSD_6_6 Changes since 1.73: +3 -3 lines
When system calls indicate an error they return -1, not some arbitrary
value < 0. errno is only updated in this case. Change all (most?)
callers of syscalls to follow this better, and let's see if this strictness
helps us in the future.
|
/* $OpenBSD: canohost.c,v 1.74 2019/06/28 13:35:04 deraadt Exp $ */
/*
* Author: Tatu Ylonen <ylo@cs.hut.fi>
* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
* All rights reserved
* Functions for returning the canonical host name of the remote site.
*
* As far as I am concerned, the code I have written for this software
* can be used freely for any purpose. Any derived versions of this
* software must be clearly marked as such, and if the derived work is
* incompatible with the protocol description in the RFC file, it must be
* called by a name other than "ssh" or "Secure Shell".
*/
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <netinet/in.h>
#include <errno.h>
#include <netdb.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdarg.h>
#include <unistd.h>
#include "xmalloc.h"
#include "packet.h"
#include "log.h"
#include "canohost.h"
#include "misc.h"
/*
* Returns the local/remote IP-address/hostname of socket as a string.
* The returned string must be freed.
*/
static char *
get_socket_address(int sock, int remote, int flags)
{
struct sockaddr_storage addr;
socklen_t addrlen;
char ntop[NI_MAXHOST];
int r;
/* Get IP address of client. */
addrlen = sizeof(addr);
memset(&addr, 0, sizeof(addr));
if (remote) {
if (getpeername(sock, (struct sockaddr *)&addr, &addrlen) != 0)
return NULL;
} else {
if (getsockname(sock, (struct sockaddr *)&addr, &addrlen) != 0)
return NULL;
}
switch (addr.ss_family) {
case AF_INET:
case AF_INET6:
/* Get the address in ascii. */
if ((r = getnameinfo((struct sockaddr *)&addr, addrlen, ntop,
sizeof(ntop), NULL, 0, flags)) != 0) {
error("%s: getnameinfo %d failed: %s", __func__,
flags, ssh_gai_strerror(r));
return NULL;
}
return xstrdup(ntop);
case AF_UNIX:
/* Get the Unix domain socket path. */
return xstrdup(((struct sockaddr_un *)&addr)->sun_path);
default:
/* We can't look up remote Unix domain sockets. */
return NULL;
}
}
char *
get_peer_ipaddr(int sock)
{
char *p;
if ((p = get_socket_address(sock, 1, NI_NUMERICHOST)) != NULL)
return p;
return xstrdup("UNKNOWN");
}
char *
get_local_ipaddr(int sock)
{
char *p;
if ((p = get_socket_address(sock, 0, NI_NUMERICHOST)) != NULL)
return p;
return xstrdup("UNKNOWN");
}
char *
get_local_name(int fd)
{
char *host, myname[NI_MAXHOST];
/* Assume we were passed a socket */
if ((host = get_socket_address(fd, 0, NI_NAMEREQD)) != NULL)
return host;
/* Handle the case where we were passed a pipe */
if (gethostname(myname, sizeof(myname)) == -1) {
verbose("%s: gethostname: %s", __func__, strerror(errno));
host = xstrdup("UNKNOWN");
} else {
host = xstrdup(myname);
}
return host;
}
/* Returns the local/remote port for the socket. */
static int
get_sock_port(int sock, int local)
{
struct sockaddr_storage from;
socklen_t fromlen;
char strport[NI_MAXSERV];
int r;
/* Get IP address of client. */
fromlen = sizeof(from);
memset(&from, 0, sizeof(from));
if (local) {
if (getsockname(sock, (struct sockaddr *)&from, &fromlen) == -1) {
error("getsockname failed: %.100s", strerror(errno));
return 0;
}
} else {
if (getpeername(sock, (struct sockaddr *)&from, &fromlen) == -1) {
debug("getpeername failed: %.100s", strerror(errno));
return -1;
}
}
/* Non-inet sockets don't have a port number. */
if (from.ss_family != AF_INET && from.ss_family != AF_INET6)
return 0;
/* Return port number. */
if ((r = getnameinfo((struct sockaddr *)&from, fromlen, NULL, 0,
strport, sizeof(strport), NI_NUMERICSERV)) != 0)
fatal("%s: getnameinfo NI_NUMERICSERV failed: %s", __func__,
ssh_gai_strerror(r));
return atoi(strport);
}
int
get_peer_port(int sock)
{
return get_sock_port(sock, 0);
}
int
get_local_port(int sock)
{
return get_sock_port(sock, 1);
}