*/
#include "includes.h"
-RCSID("$OpenBSD: canohost.c,v 1.34 2002/09/23 20:46:27 stevesk Exp $");
+RCSID("$OpenBSD: canohost.c,v 1.38 2003/09/23 20:17:11 markus Exp $");
#include "packet.h"
#include "xmalloc.h"
#include "canohost.h"
static void check_ip_options(int, char *);
+static void ipv64_normalise_mapped(struct sockaddr_storage *, socklen_t *);
/*
* Return the canonical name of the host at the other end of the socket. The
*/
static char *
-get_remote_hostname(int socket, int verify_reverse_mapping)
+get_remote_hostname(int socket, int use_dns)
{
struct sockaddr_storage from;
int i;
/* Get IP address of client. */
fromlen = sizeof(from);
memset(&from, 0, sizeof(from));
- if (getpeername(socket, (struct sockaddr *) &from, &fromlen) < 0) {
+ if (getpeername(socket, (struct sockaddr *)&from, &fromlen) < 0) {
debug("getpeername failed: %.100s", strerror(errno));
- fatal_cleanup();
+ cleanup_exit(255);
}
-#ifdef IPV4_IN_IPV6
- if (from.ss_family == AF_INET6) {
- struct sockaddr_in6 *from6 = (struct sockaddr_in6 *)&from;
- /* Detect IPv4 in IPv6 mapped address and convert it to */
- /* plain (AF_INET) IPv4 address */
- if (IN6_IS_ADDR_V4MAPPED(&from6->sin6_addr)) {
- struct sockaddr_in *from4 = (struct sockaddr_in *)&from;
- struct in_addr addr;
- u_int16_t port;
+ ipv64_normalise_mapped(&from, &fromlen);
- memcpy(&addr, ((char *)&from6->sin6_addr) + 12, sizeof(addr));
- port = from6->sin6_port;
-
- memset(&from, 0, sizeof(from));
-
- from4->sin_family = AF_INET;
- memcpy(&from4->sin_addr, &addr, sizeof(addr));
- from4->sin_port = port;
- }
- }
-#endif
+ if (from.ss_family == AF_INET6)
+ fromlen = sizeof(struct sockaddr_in6);
if (getnameinfo((struct sockaddr *)&from, fromlen, ntop, sizeof(ntop),
NULL, 0, NI_NUMERICHOST) != 0)
fatal("get_remote_hostname: getnameinfo NI_NUMERICHOST failed");
+ if (!use_dns)
+ return xstrdup(ntop);
+
if (from.ss_family == AF_INET)
check_ip_options(socket, ntop);
if (getnameinfo((struct sockaddr *)&from, fromlen, name, sizeof(name),
NULL, 0, NI_NAMEREQD) != 0) {
/* Host name not found. Use ip address. */
-#if 0
- log("Could not reverse map address %.100s.", ntop);
-#endif
return xstrdup(ntop);
}
- /* Got host name. */
- name[sizeof(name) - 1] = '\0';
+ /*
+ * if reverse lookup result looks like a numeric hostname,
+ * someone is trying to trick us by PTR record like following:
+ * 1.1.1.10.in-addr.arpa. IN PTR 2.3.4.5
+ */
+ memset(&hints, 0, sizeof(hints));
+ hints.ai_socktype = SOCK_DGRAM; /*dummy*/
+ hints.ai_flags = AI_NUMERICHOST;
+ if (getaddrinfo(name, "0", &hints, &ai) == 0) {
+ logit("Nasty PTR record \"%s\" is set up for %s, ignoring",
+ name, ntop);
+ freeaddrinfo(ai);
+ return xstrdup(ntop);
+ }
+
/*
* Convert it to all lowercase (which is expected by the rest
* of this software).
for (i = 0; name[i]; i++)
if (isupper(name[i]))
name[i] = tolower(name[i]);
-
- if (!verify_reverse_mapping)
- return xstrdup(name);
/*
* Map it back to an IP address and check that the given
* address actually is an address of this host. This is
hints.ai_family = from.ss_family;
hints.ai_socktype = SOCK_STREAM;
if (getaddrinfo(name, NULL, &hints, &aitop) != 0) {
- log("reverse mapping checking getaddrinfo for %.700s "
+ logit("reverse mapping checking getaddrinfo for %.700s "
"failed - POSSIBLE BREAKIN ATTEMPT!", name);
return xstrdup(ntop);
}
/* If we reached the end of the list, the address was not there. */
if (!ai) {
/* Address not found for the host name. */
- log("Address %.100s maps to %.600s, but this does not "
+ logit("Address %.100s maps to %.600s, but this does not "
"map back to the address - POSSIBLE BREAKIN ATTEMPT!",
ntop, name);
return xstrdup(ntop);
static void
check_ip_options(int socket, char *ipaddr)
{
+#ifdef IP_OPTIONS
u_char options[200];
char text[sizeof(options) * 3 + 1];
socklen_t option_size;
for (i = 0; i < option_size; i++)
snprintf(text + i*3, sizeof(text) - i*3,
" %2.2x", options[i]);
- log("Connection from %.100s with IP options:%.800s",
+ logit("Connection from %.100s with IP options:%.800s",
ipaddr, text);
packet_disconnect("Connection from %.100s with IP options:%.800s",
ipaddr, text);
}
+#endif /* IP_OPTIONS */
+}
+
+static void
+ipv64_normalise_mapped(struct sockaddr_storage *addr, socklen_t *len)
+{
+ struct sockaddr_in6 *a6 = (struct sockaddr_in6 *)addr;
+ struct sockaddr_in *a4 = (struct sockaddr_in *)addr;
+ struct in_addr inaddr;
+ u_int16_t port;
+
+ if (addr->ss_family != AF_INET6 ||
+ !IN6_IS_ADDR_V4MAPPED(&a6->sin6_addr))
+ return;
+
+ debug3("Normalising mapped IPv4 in IPv6 address");
+
+ memcpy(&inaddr, ((char *)&a6->sin6_addr) + 12, sizeof(inaddr));
+ port = a6->sin6_port;
+
+ memset(addr, 0, sizeof(*a4));
+
+ a4->sin_family = AF_INET;
+ *len = sizeof(*a4);
+ memcpy(&a4->sin_addr, &inaddr, sizeof(inaddr));
+ a4->sin_port = port;
}
/*
*/
const char *
-get_canonical_hostname(int verify_reverse_mapping)
+get_canonical_hostname(int use_dns)
{
static char *canonical_host_name = NULL;
- static int verify_reverse_mapping_done = 0;
+ static int use_dns_done = 0;
/* Check if we have previously retrieved name with same option. */
if (canonical_host_name != NULL) {
- if (verify_reverse_mapping_done != verify_reverse_mapping)
+ if (use_dns_done != use_dns)
xfree(canonical_host_name);
else
return canonical_host_name;
/* Get the real hostname if socket; otherwise return UNKNOWN. */
if (packet_connection_is_on_socket())
canonical_host_name = get_remote_hostname(
- packet_get_connection_in(), verify_reverse_mapping);
+ packet_get_connection_in(), use_dns);
else
canonical_host_name = xstrdup("UNKNOWN");
- verify_reverse_mapping_done = verify_reverse_mapping;
+ use_dns_done = use_dns;
return canonical_host_name;
}
/*
- * Returns the remote IP-address of socket as a string. The returned
- * string must be freed.
+ * Returns the local/remote IP-address/hostname of socket as a string.
+ * The returned string must be freed.
*/
static char *
get_socket_address(int socket, int remote, int flags)
< 0)
return NULL;
}
+
+ /* Work around Linux IPv6 weirdness */
+ if (addr.ss_family == AF_INET6)
+ addrlen = sizeof(struct sockaddr_in6);
+
/* Get the address in ascii. */
if (getnameinfo((struct sockaddr *)&addr, addrlen, ntop, sizeof(ntop),
NULL, 0, flags) != 0) {
- error("get_socket_ipaddr: getnameinfo %d failed", flags);
+ error("get_socket_address: getnameinfo %d failed", flags);
return NULL;
}
return xstrdup(ntop);
canonical_host_ip =
get_peer_ipaddr(packet_get_connection_in());
if (canonical_host_ip == NULL)
- fatal_cleanup();
+ cleanup_exit(255);
} else {
/* If not on socket, return UNKNOWN. */
canonical_host_ip = xstrdup("UNKNOWN");
}
const char *
-get_remote_name_or_ip(u_int utmp_len, int verify_reverse_mapping)
+get_remote_name_or_ip(u_int utmp_len, int use_dns)
{
static const char *remote = "";
if (utmp_len > 0)
- remote = get_canonical_hostname(verify_reverse_mapping);
+ remote = get_canonical_hostname(use_dns);
if (utmp_len == 0 || strlen(remote) > utmp_len)
remote = get_remote_ipaddr();
return remote;
return 0;
}
} else {
- if (getpeername(sock, (struct sockaddr *) & from, &fromlen) < 0) {
+ if (getpeername(sock, (struct sockaddr *)&from, &fromlen) < 0) {
debug("getpeername failed: %.100s", strerror(errno));
- fatal_cleanup();
+ cleanup_exit(255);
}
}
+
+ /* Work around Linux IPv6 weirdness */
+ if (from.ss_family == AF_INET6)
+ fromlen = sizeof(struct sockaddr_in6);
+
/* Return port number. */
if (getnameinfo((struct sockaddr *)&from, fromlen, NULL, 0,
strport, sizeof(strport), NI_NUMERICSERV) != 0)
andersk / openssh.git / blobdiff