Vendor import of OpenSSH.

1 files changed, 274 insertions, 0 deletions

diff --git a/crypto/openssh/canohost.c b/crypto/openssh/canohost.c
new file mode 100644
index 0000000..fcf743c
--- /dev/null
+++ b/crypto/openssh/canohost.c
@@ -0,0 +1,274 @@
+/*
+ * 
+ * canohost.c
+ * 
+ * Author: Tatu Ylonen <ylo@cs.hut.fi>
+ * 
+ * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
+ *                    All rights reserved
+ * 
+ * Created: Sun Jul  2 17:52:22 1995 ylo
+ * 
+ * Functions for returning the canonical host name of the remote site.
+ * 
+ */
+
+#include "includes.h"
+RCSID("$Id: canohost.c,v 1.11 2000/01/04 13:41:32 markus Exp $");
+
+#include "packet.h"
+#include "xmalloc.h"
+#include "ssh.h"
+
+/*
+ * Return the canonical name of the host at the other end of the socket. The
+ * caller should free the returned string with xfree.
+ */
+
+char *
+get_remote_hostname(int socket)
+{
+	struct sockaddr_storage from;
+	int i;
+	socklen_t fromlen;
+	struct addrinfo hints, *ai, *aitop;
+	char name[MAXHOSTNAMELEN];
+	char ntop[NI_MAXHOST], ntop2[NI_MAXHOST];
+
+	/* Get IP address of client. */
+	fromlen = sizeof(from);
+	memset(&from, 0, sizeof(from));
+	if (getpeername(socket, (struct sockaddr *) & from, &fromlen) < 0) {
+		debug("getpeername failed: %.100s", strerror(errno));
+		fatal_cleanup();
+	}
+	if (getnameinfo((struct sockaddr *)&from, fromlen, ntop, sizeof(ntop),
+	     NULL, 0, NI_NUMERICHOST) != 0)
+		fatal("get_remote_hostname: getnameinfo NI_NUMERICHOST failed");
+
+	/* Map the IP address to a host name. */
+	if (getnameinfo((struct sockaddr *)&from, fromlen, name, sizeof(name),
+	     NULL, 0, NI_NAMEREQD) == 0) {
+		/* Got host name. */
+		name[sizeof(name) - 1] = '\0';
+		/*
+		 * 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]);
+
+		/*
+		 * Map it back to an IP address and check that the given
+		 * address actually is an address of this host.  This is
+		 * necessary because anyone with access to a name server can
+		 * define arbitrary names for an IP address. 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).
+		 */
+		memset(&hints, 0, sizeof(hints));
+		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 failed - POSSIBLE BREAKIN ATTEMPT!", name);
+			strlcpy(name, ntop, sizeof name);
+			goto check_ip_options;
+		}
+		/* Look for the address from the list of addresses. */
+		for (ai = aitop; ai; ai = ai->ai_next) {
+			if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop2,
+			    sizeof(ntop2), NULL, 0, NI_NUMERICHOST) == 0 &&
+			    (strcmp(ntop, ntop2) == 0))
+					break;
+		}
+		freeaddrinfo(aitop);
+		/* 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 map back to the address - POSSIBLE BREAKIN ATTEMPT!",
+			    ntop, name);
+			strlcpy(name, ntop, sizeof name);
+			goto check_ip_options;
+		}
+		/* Address was found for the host name.  We accept the host name. */
+	} else {
+		/* Host name not found.  Use ascii representation of the address. */
+		strlcpy(name, ntop, sizeof name);
+		log("Could not reverse map address %.100s.", name);
+	}
+
+check_ip_options:
+
+	/*
+	 * If IP options are supported, make sure there are none (log and
+	 * disconnect them if any are found).  Basically we are worried about
+	 * source routing; it can be used to pretend you are somebody
+	 * (ip-address) you are not. That itself may be "almost acceptable"
+	 * under certain circumstances, but rhosts autentication is useless
+	 * if source routing is accepted. 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.
+	 */
+	/* IP options -- IPv4 only */
+	if (from.ss_family == AF_INET) {
+		unsigned char options[200], *ucp;
+		char text[1024], *cp;
+		socklen_t option_size;
+		int ipproto;
+		struct protoent *ip;
+
+		if ((ip = getprotobyname("ip")) != NULL)
+			ipproto = ip->p_proto;
+		else
+			ipproto = IPPROTO_IP;
+		option_size = sizeof(options);
+		if (getsockopt(0, ipproto, IP_OPTIONS, (char *) options,
+		    &option_size) >= 0 && option_size != 0) {
+			cp = text;
+			/* Note: "text" buffer must be at least 3x as big as options. */
+			for (ucp = options; option_size > 0; ucp++, option_size--, cp += 3)
+				sprintf(cp, " %2.2x", *ucp);
+			log("Connection from %.100s with IP options:%.800s",
+			    ntop, text);
+			packet_disconnect("Connection from %.100s with IP options:%.800s",
+					  ntop, text);
+		}
+	}
+
+	return xstrdup(name);
+}
+
+/*
+ * Return the canonical name of the host in the other side of the current
+ * connection.  The host name is cached, so it is efficient to call this
+ * several times.
+ */
+
+const char *
+get_canonical_hostname()
+{
+	static char *canonical_host_name = NULL;
+
+	/* Check if we have previously retrieved this same name. */
+	if (canonical_host_name != NULL)
+		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());
+	else
+		canonical_host_name = xstrdup("UNKNOWN");
+
+	return canonical_host_name;
+}
+
+/*
+ * Returns the IP-address of the remote host as a string.  The returned
+ * string must not be freed.
+ */
+
+const char *
+get_remote_ipaddr()
+{
+	static char *canonical_host_ip = NULL;
+	struct sockaddr_storage from;
+	socklen_t fromlen;
+	int socket;
+	char ntop[NI_MAXHOST];
+
+	/* Check whether we have chached the name. */
+	if (canonical_host_ip != NULL)
+		return canonical_host_ip;
+
+	/* If not a socket, return UNKNOWN. */
+	if (!packet_connection_is_on_socket()) {
+		canonical_host_ip = xstrdup("UNKNOWN");
+		return canonical_host_ip;
+	}
+	/* Get client socket. */
+	socket = packet_get_connection_in();
+
+	/* Get IP address of client. */
+	fromlen = sizeof(from);
+	memset(&from, 0, sizeof(from));
+	if (getpeername(socket, (struct sockaddr *) & from, &fromlen) < 0) {
+		debug("getpeername failed: %.100s", strerror(errno));
+		fatal_cleanup();
+	}
+	/* Get the IP address in ascii. */
+	if (getnameinfo((struct sockaddr *)&from, fromlen, ntop, sizeof(ntop),
+	     NULL, 0, NI_NUMERICHOST) != 0)
+		fatal("get_remote_hostname: getnameinfo NI_NUMERICHOST failed");
+
+	canonical_host_ip = xstrdup(ntop);
+
+	/* Return ip address string. */
+	return canonical_host_ip;
+}
+
+/* Returns the local/remote port for the socket. */
+
+int
+get_sock_port(int sock, int local)
+{
+	struct sockaddr_storage from;
+	socklen_t fromlen;
+	char strport[NI_MAXSERV];
+
+	/* Get IP address of client. */
+	fromlen = sizeof(from);
+	memset(&from, 0, sizeof(from));
+	if (local) {
+		if (getsockname(sock, (struct sockaddr *)&from, &fromlen) < 0) {
+			error("getsockname failed: %.100s", strerror(errno));
+			return 0;
+		}
+	} else {
+		if (getpeername(sock, (struct sockaddr *) & from, &fromlen) < 0) {
+			debug("getpeername failed: %.100s", strerror(errno));
+			fatal_cleanup();
+		}
+	}
+	/* Return port number. */
+	if (getnameinfo((struct sockaddr *)&from, fromlen, NULL, 0,
+	     strport, sizeof(strport), NI_NUMERICSERV) != 0)
+		fatal("get_sock_port: getnameinfo NI_NUMERICSERV failed");
+	return atoi(strport);
+}
+
+/* Returns remote/local port number for the current connection. */
+
+int 
+get_port(int local)
+{
+	/*
+	 * If the connection is not a socket, return 65535.  This is
+	 * intentionally chosen to be an unprivileged port number.
+	 */
+	if (!packet_connection_is_on_socket())
+		return 65535;
+
+	/* Get socket and return the port number. */
+	return get_sock_port(packet_get_connection_in(), local);
+}
+
+int 
+get_peer_port(int sock)
+{
+	return get_sock_port(sock, 0);
+}
+
+int 
+get_remote_port()
+{
+	return get_port(0);
+}
+
+int
+get_local_port()
+{
+	return get_port(1);
+}