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|
$NetBSD: patch-aw,v 1.1 2000/03/20 02:25:41 itojun Exp $
--- canohost.c.orig Wed May 12 07:19:24 1999
+++ canohost.c Fri Dec 24 21:50:38 1999
@@ -59,10 +59,11 @@
char *get_remote_hostname(int socket)
{
- struct sockaddr_in from;
+ struct sockaddr_storage from;
int fromlen, i;
- struct hostent *hp;
+ struct addrinfo hints, *ai, *aitop;
char name[255];
+ char ntop[ADDRSTRLEN], ntop2[ADDRSTRLEN];
/* Get IP address of client. */
fromlen = sizeof(from);
@@ -73,14 +74,16 @@
strcpy(name, "UNKNOWN");
goto check_ip_options;
}
+
+ getnameinfo((struct sockaddr *)&from, fromlen,
+ ntop, sizeof(ntop), NULL, 0, NI_NUMERICHOST);
/* Map the IP address to a host name. */
- hp = gethostbyaddr((char *)&from.sin_addr, sizeof(struct in_addr),
- from.sin_family);
- if (hp)
+ if (getnameinfo((struct sockaddr *)&from, fromlen,
+ name, sizeof(name),
+ NULL, 0, NI_NAMEREQD) == 0)
{
/* Got host name. */
- strncpy(name, hp->h_name, sizeof(name));
name[sizeof(name) - 1] = '\0';
/* Convert it to all lowercase (which is expected by the rest of this
@@ -95,25 +98,30 @@
Mapping from name to IP address can be trusted better (but can still
be fooled if the intruder has access to the name server of the
domain). */
- hp = gethostbyname(name);
- if (!hp)
+ memset(&hints, 0, sizeof(hints));
+ hints.ai_family = from.__ss_family;
+ if (getaddrinfo(name, NULL, &hints, &aitop) != 0)
{
log_msg("reverse mapping checking gethostbyname for %.700s failed - POSSIBLE BREAKIN ATTEMPT!", name);
- strcpy(name, inet_ntoa(from.sin_addr));
+ strcpy(name, ntop);
goto check_ip_options;
}
/* Look for the address from the list of addresses. */
- for (i = 0; hp->h_addr_list[i]; i++)
- if (memcmp(hp->h_addr_list[i], &from.sin_addr, sizeof(from.sin_addr))
- == 0)
- break;
+ for (ai = aitop; ai; ai = ai->ai_next)
+ {
+ getnameinfo(ai->ai_addr, ai->ai_addrlen,
+ ntop2, sizeof(ntop2), NULL, 0, NI_NUMERICHOST);
+ if (strcmp(ntop, ntop2) == 0)
+ break;
+ }
+ freeaddrinfo(aitop);
/* If we reached the end of the list, the address was not there. */
- if (!hp->h_addr_list[i])
+ if (!ai)
{
/* Address not found for the host name. */
log_msg("Address %.100s maps to %.600s, but this does not map back to the address - POSSIBLE BREAKIN ATTEMPT!",
- inet_ntoa(from.sin_addr), name);
- strcpy(name, inet_ntoa(from.sin_addr));
+ ntop, name);
+ strcpy(name, ntop);
goto check_ip_options;
}
/* Address was found for the host name. We accept the host name. */
@@ -121,7 +129,7 @@
else
{
/* Host name not found. Use ascii representation of the address. */
- strcpy(name, inet_ntoa(from.sin_addr));
+ strcpy(name, ntop);
log_msg("Could not reverse map address %.100s.", name);
}
@@ -136,6 +144,7 @@
Notice also that if we just dropped source routing here, the other
side could use IP spoofing to do rest of the interaction and could still
bypass security. So we exit here if we detect any IP options. */
+ if (from.__ss_family == AF_INET) /* IP options -- IPv4 only */
{
unsigned char options[200], *ucp;
char text[1024], *cp;
@@ -157,9 +166,9 @@
for (ucp = options; option_size > 0; ucp++, option_size--, cp += 3)
sprintf(cp, " %2.2x", *ucp);
log_msg("Connection from %.100s with IP options:%.800s",
- inet_ntoa(from.sin_addr), text);
+ ntop, text);
packet_disconnect("Connection from %.100s with IP options:%.800s",
- inet_ntoa(from.sin_addr), text);
+ ntop, text);
}
}
#endif
@@ -177,7 +186,7 @@
const char *get_canonical_hostname(void)
{
int fromlen, tolen;
- struct sockaddr_in from, to;
+ struct sockaddr_storage from, to;
/* Check if we have previously retrieved this same name. */
if (canonical_host_name != NULL)
@@ -200,8 +209,7 @@
&tolen) < 0)
goto no_ip_addr;
- if (from.sin_family == AF_INET && to.sin_family == AF_INET &&
- memcmp(&from, &to, sizeof(from)) == 0)
+ if (fromlen == tolen && memcmp(&from, &to, fromlen) == 0)
goto return_ip_addr;
no_ip_addr:
@@ -221,8 +229,9 @@
const char *get_remote_ipaddr(void)
{
- struct sockaddr_in from, to;
+ struct sockaddr_storage from, to;
int fromlen, tolen, socket;
+ char ntop[ADDRSTRLEN];
/* Check if we have previously retrieved this same name. */
if (canonical_host_ip != NULL)
@@ -245,8 +254,7 @@
&tolen) < 0)
goto no_ip_addr;
- if (from.sin_family == AF_INET && to.sin_family == AF_INET &&
- memcmp(&from, &to, sizeof(from)) == 0)
+ if (fromlen == tolen && memcmp(&from, &to, fromlen) == 0)
goto return_ip_addr;
no_ip_addr:
@@ -269,7 +277,9 @@
}
/* Get the IP address in ascii. */
- canonical_host_ip = xstrdup(inet_ntoa(from.sin_addr));
+ getnameinfo((struct sockaddr *)&from, fromlen,
+ ntop, sizeof(ntop), NULL, 0, NI_NUMERICHOST);
+ canonical_host_ip = xstrdup(ntop);
/* Return ip address string. */
return canonical_host_ip;
@@ -279,8 +289,9 @@
int get_peer_port(int sock)
{
- struct sockaddr_in from;
+ struct sockaddr_storage from;
int fromlen;
+ char strport[PORTSTRLEN];
/* Get IP address of client. */
fromlen = sizeof(from);
@@ -292,7 +303,9 @@
}
/* Return port number. */
- return ntohs(from.sin_port);
+ getnameinfo((struct sockaddr *)&from, fromlen,
+ NULL, 0, strport, sizeof(strport), NI_NUMERICSERV);
+ return atoi(strport);
}
/* Returns the port number of the remote host. */
@@ -301,7 +314,7 @@
{
int socket;
int fromlen, tolen;
- struct sockaddr_in from, to;
+ struct sockaddr_storage from, to;
/* If two different descriptors, check if they are internet-domain, and
have the same address. */
@@ -319,8 +332,7 @@
&tolen) < 0)
goto no_ip_addr;
- if (from.sin_family == AF_INET && to.sin_family == AF_INET &&
- memcmp(&from, &to, sizeof(from)) == 0)
+ if (fromlen == tolen && memcmp(&from, &to, fromlen) == 0)
goto return_port;
no_ip_addr:
@@ -335,3 +347,67 @@
/* Get and return the peer port number. */
return get_peer_port(socket);
}
+
+/* Returns the port of the local of the socket. */
+
+int get_sock_port(int sock)
+{
+ struct sockaddr_storage from;
+ int fromlen;
+ char strport[PORTSTRLEN];
+
+ /* Get IP address of client. */
+ fromlen = sizeof(from);
+ memset(&from, 0, sizeof(from));
+ if (getsockname(sock, (struct sockaddr *)&from, &fromlen) < 0)
+ {
+ error("getsockname failed: %.100s", strerror(errno));
+ return 0;
+ }
+
+ /* Return port number. */
+ getnameinfo((struct sockaddr *)&from, fromlen,
+ NULL, 0, strport, sizeof(strport), NI_NUMERICSERV);
+ return atoi(strport);
+}
+
+/* Returns the port number of the local host. */
+
+int get_local_port()
+{
+ int socket;
+ int fromlen, tolen;
+ struct sockaddr_storage from, to;
+
+ /* If two different descriptors, check if they are internet-domain, and
+ have the same address. */
+ if (packet_get_connection_in() != packet_get_connection_out())
+ {
+ fromlen = sizeof(from);
+ memset(&from, 0, sizeof(from));
+ if (getsockname(packet_get_connection_in(), (struct sockaddr *)&from,
+ &fromlen) < 0)
+ goto no_ip_addr;
+
+ tolen = sizeof(to);
+ memset(&to, 0, sizeof(to));
+ if (getsockname(packet_get_connection_out(), (struct sockaddr *)&to,
+ &tolen) < 0)
+ goto no_ip_addr;
+
+ if (fromlen == tolen && memcmp(&from, &to, fromlen) == 0)
+ goto return_port;
+
+ no_ip_addr:
+ return 65535;
+ }
+
+ return_port:
+
+ /* Get client socket. */
+ socket = packet_get_connection_in();
+
+ /* Get and return the local port number. */
+ return get_sock_port(socket);
+}
+
|
