cleanup EPSV/EPRT error handling. avoid possible memory leak (getaddrinfo).

correct error code on unsupported protocol parameter against EPRT (522).

3 files changed, 200 insertions, 129 deletions

diff --git a/libexec/ftpd/extern.h b/libexec/ftpd/extern.h
index cd92578a36a..131164b1f68 100644
--- a/libexec/ftpd/extern.h
+++ b/libexec/ftpd/extern.h
@@ -79,7 +79,13 @@ void	makedir __P((char *));
 void	nack __P((char *));
 void	pass __P((char *));
 void	passive __P((void));
+int	lpsvproto2af __P((int));
+int	af2lpsvproto __P((int));
+int	epsvproto2af __P((int));
+int	af2epsvproto __P((int));
 void	long_passive __P((char *, int));
+int	extended_port __P((const char *));
+void	epsv_protounsupp __P((const char *));
 void	perror_reply __P((int, char *));
 void	pwd __P((void));
 void	removedir __P((char *));
diff --git a/libexec/ftpd/ftpcmd.y b/libexec/ftpd/ftpcmd.y
index 1631f12520c..1ec6ab95af2 100644
--- a/libexec/ftpd/ftpcmd.y
+++ b/libexec/ftpd/ftpcmd.y
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ftpcmd.y,v 1.23 2000/11/13 16:14:44 itojun Exp $	*/
+/*	$OpenBSD: ftpcmd.y,v 1.24 2000/11/14 20:27:01 itojun Exp $	*/
 /*	$NetBSD: ftpcmd.y,v 1.7 1996/04/08 19:03:11 jtc Exp $	*/
 
 /*
@@ -47,7 +47,7 @@
 #if 0
 static char sccsid[] = "@(#)ftpcmd.y	8.3 (Berkeley) 4/6/94";
 #else
-static char rcsid[] = "$OpenBSD: ftpcmd.y,v 1.23 2000/11/13 16:14:44 itojun Exp $";
+static char rcsid[] = "$OpenBSD: ftpcmd.y,v 1.24 2000/11/14 20:27:01 itojun Exp $";
 #endif
 #endif /* not lint */
 
@@ -235,93 +235,8 @@ cmd
 
 	| EPRT check_login_epsvall SP STRING CRLF
 		{
-			char *tmp = NULL;
-			char *result[3];
-			char *p, *q;
-			char delim;
-			struct addrinfo hints;
-			struct addrinfo *res;
-			int i;
-
-			if ($2) { /* XXX indentation */
-
-			if (epsvall) {
-				reply(501, "EPRT disallowed after EPSV ALL");
-				goto eprt_done;
-			}
-			usedefault = 0;
-			if (pdata >= 0) {
-				(void) close(pdata);
-				pdata = -1;
-			}
-
-			/*XXX checks for login */
-
-			tmp = strdup($4);
-			if (!tmp) {
-				fatal("not enough core.");
-				/*NOTREACHED*/
-			}
-			p = tmp;
-			delim = p[0];
-			p++;
-			memset(result, 0, sizeof(result));
-			for (i = 0; i < 3; i++) {
-				q = strchr(p, delim);
-				if (!q || *q != delim) {
-		parsefail:
-					reply(500, "Invalid argument, rejected.");
-					if (tmp)
-						free(tmp);
-					usedefault = 1;
-					goto eprt_done;
-				}
-				*q++ = '\0';
-				result[i] = p;
-				p = q;
-			}
-
-			/* some more sanity check */
-			p = result[0];
-			while (*p) {
-				if (!isdigit(*p))
-					goto parsefail;
-				p++;
-			}
-			p = result[2];
-			while (*p) {
-				if (!isdigit(*p))
-					goto parsefail;
-				p++;
-			}
-
-			memset(&hints, 0, sizeof(hints));
-			if (atoi(result[0]) == 1)
-				hints.ai_family = PF_INET;
-			if (atoi(result[0]) == 2)
-				hints.ai_family = PF_INET6;
-			else
-				hints.ai_family = PF_UNSPEC;	/*XXX*/
-			hints.ai_socktype = SOCK_STREAM;
-			if (getaddrinfo(result[1], result[2], &hints, &res))
-				goto parsefail;
-			memcpy(&data_dest, res->ai_addr, res->ai_addrlen);
-			if (his_addr.su_family == AF_INET6 &&
-			    data_dest.su_family == AF_INET6) {
-				/* XXX more sanity checks! */
-				data_dest.su_sin6.sin6_scope_id =
-				    his_addr.su_sin6.sin6_scope_id;
-			}
-			free(tmp);
-			tmp = NULL;
-			if (pdata >= 0) {
-				(void) close(pdata);
-				pdata = -1;
-			}
-			reply(200, "EPRT command successful.");
-		eprt_done:;
-
-			}
+			if ($2)
+				extended_port($4);
 		}
 
 	| PASV check_login_epsvall CRLF
@@ -336,21 +251,8 @@ cmd
 		}
 	| EPSV check_login SP NUMBER CRLF
 		{
-			int pf;
-			if ($2) {
-				switch ($4) {
-				case 1:
-					pf = PF_INET;
-					break;
-				case 2:
-					pf = PF_INET6;
-					break;
-				default:
-					pf = -1;	/*junk*/
-					break;
-				}
-				long_passive("EPSV", pf);
-			}
+			if ($2)
+				long_passive("EPSV", epsvproto2af($4));
 		}
 	| EPSV check_login SP ALL CRLF
 		{
diff --git a/libexec/ftpd/ftpd.c b/libexec/ftpd/ftpd.c
index 0d1a817b7d0..d1f93705ff3 100644
--- a/libexec/ftpd/ftpd.c
+++ b/libexec/ftpd/ftpd.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ftpd.c,v 1.79 2000/09/15 07:13:45 deraadt Exp $	*/
+/*	$OpenBSD: ftpd.c,v 1.80 2000/11/14 20:27:01 itojun Exp $	*/
 /*	$NetBSD: ftpd.c,v 1.15 1995/06/03 22:46:47 mycroft Exp $	*/
 
 /*
@@ -2179,6 +2179,61 @@ pasv_error:
 }
 
 /*
+ * convert protocol identifier to/from AF
+ */
+int
+lpsvproto2af(int proto)
+{
+
+	switch (proto) {
+	case 4:	return AF_INET;
+#ifdef INET6
+	case 6:	return AF_INET6;
+#endif
+	default: return -1;
+	}
+}
+
+int
+af2lpsvproto(int af)
+{
+
+	switch (af) {
+	case AF_INET:	return 4;
+#ifdef INET6
+	case AF_INET6:	return 6;
+#endif
+	default:	return -1;
+	}
+}
+
+int
+epsvproto2af(int proto)
+{
+
+	switch (proto) {
+	case 1:	return AF_INET;
+#ifdef INET6
+	case 2:	return AF_INET6;
+#endif
+	default: return -1;
+	}
+}
+
+int
+af2epsvproto(int af)
+{
+
+	switch (af) {
+	case AF_INET:	return 1;
+#ifdef INET6
+	case AF_INET6:	return 2;
+#endif
+	default:	return -1;
+	}
+}
+
+/*
  * 228 Entering Long Passive Mode (af, hal, h1, h2, h3,..., pal, p1, p2...)
  * 229 Entering Extended Passive Mode (|||port|)
  */
@@ -2194,31 +2249,17 @@ long_passive(char *cmd, int pf)
 		return;
 	}
 
-	if (pf != PF_UNSPEC) {
-		if (ctrl_addr.su_family != pf) {
-			switch (ctrl_addr.su_family) {
-			case AF_INET:
-				pf = 1;
-				break;
-			case AF_INET6:
-				pf = 2;
-				break;
-			default:
-				pf = 0;
-				break;
-			}
-			/*
-			 * XXX
-			 * only EPRT/EPSV ready clients will understand this
-			 */
-			if (strcmp(cmd, "EPSV") == 0 && pf) {
-				reply(522, "Network protocol mismatch, "
-				    "use (%d)", pf);
-			} else
-				reply(501, "Network protocol mismatch"); /*XXX*/
+	if (pf != PF_UNSPEC && ctrl_addr.su_family != pf) {
+		/*
+		 * XXX
+		 * only EPRT/EPSV ready clients will understand this
+		 */
+		if (strcmp(cmd, "EPSV") != 0)
+			reply(501, "Network protocol mismatch"); /*XXX*/
+		else
+			epsv_protounsupp("Network protocol mismatch");
 
-			return;
-		}
+		return;
 	}
  		
 	if (pdata >= 0)
@@ -2312,6 +2353,128 @@ long_passive(char *cmd, int pf)
 }
 
 /*
+ * EPRT |proto|addr|port|
+ */
+int
+extended_port(const char *arg)
+{
+	char *tmp = NULL;
+	char *result[3];
+	char *p, *q;
+	char delim;
+	struct addrinfo hints;
+	struct addrinfo *res = NULL;
+	int i;
+	unsigned long proto;
+
+	if (epsvall) {
+		reply(501, "EPRT disallowed after EPSV ALL");
+		return -1;
+	}
+
+	usedefault = 0;
+	if (pdata >= 0) {
+		(void) close(pdata);
+		pdata = -1;
+	}
+
+	tmp = strdup(arg);
+	if (!tmp) {
+		fatal("not enough core.");
+		/*NOTREACHED*/
+	}
+	p = tmp;
+	delim = p[0];
+	p++;
+	memset(result, 0, sizeof(result));
+	for (i = 0; i < 3; i++) {
+		q = strchr(p, delim);
+		if (!q || *q != delim)
+			goto parsefail;
+		*q++ = '\0';
+		result[i] = p;
+		p = q;
+	}
+
+	/* some more sanity check */
+	p = NULL;
+	(void)strtoul(result[2], &p, 10);
+	if (!*result[2] || *p)
+		goto protounsupp;
+	p = NULL;
+	proto = strtoul(result[0], &p, 10);
+	if (!*result[0] || *p)
+		goto protounsupp;
+
+	memset(&hints, 0, sizeof(hints));
+	hints.ai_family = epsvproto2af((int)proto);
+	if (hints.ai_family < 0)
+		goto protounsupp;
+	hints.ai_socktype = SOCK_STREAM;
+	hints.ai_flags = AI_NUMERICHOST;	/*no DNS*/
+	if (getaddrinfo(result[1], result[2], &hints, &res))
+		goto parsefail;
+	if (res->ai_next)
+		goto parsefail;
+	if (sizeof(data_dest) < res->ai_addrlen)
+		goto parsefail;
+	memcpy(&data_dest, res->ai_addr, res->ai_addrlen);
+	if (his_addr.su_family == AF_INET6 &&
+	    data_dest.su_family == AF_INET6) {
+		/* XXX more sanity checks! */
+		data_dest.su_sin6.sin6_scope_id =
+		    his_addr.su_sin6.sin6_scope_id;
+	}
+	if (pdata >= 0) {
+		(void) close(pdata);
+		pdata = -1;
+	}
+	reply(200, "EPRT command successful.");
+
+	if (tmp)
+		free(tmp);
+	if (res)
+		freeaddrinfo(res);
+	return 0;
+
+parsefail:
+	reply(500, "Invalid argument, rejected.");
+	usedefault = 1;
+	if (tmp)
+		free(tmp);
+	if (res)
+		freeaddrinfo(res);
+	return -1;
+
+protounsupp:
+	epsv_protounsupp("Protocol not supported");
+	usedefault = 1;
+	if (tmp)
+		free(tmp);
+	if (res)
+		freeaddrinfo(res);
+	return -1;
+}
+
+/*
+ * 522 Protocol not supported (proto,...)
+ * as we assume address family for control and data connections are the same, 
+ * we do not return the list of address families we support - instead, we 
+ * return the address family of the control connection.  
+ */
+void
+epsv_protounsupp(const char *message)
+{
+	int proto;
+
+	proto = af2epsvproto(ctrl_addr.su_family);
+	if (proto < 0)
+		reply(501, "%s", message);	/*XXX*/
+	else
+		reply(522, "%s, use (%d)", message, proto);
+}
+
+/*
  * Generate unique name for file with basename "local".
  * The file named "local" is already known to exist.
  * Generates failure reply on error.