Linux-2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 400 insertions, 0 deletions

diff --git a/net/ipv4/ipvs/ip_vs_ftp.c b/net/ipv4/ipvs/ip_vs_ftp.c
new file mode 100644
index 00000000000..a19a33ceb81
--- /dev/null
+++ b/net/ipv4/ipvs/ip_vs_ftp.c
@@ -0,0 +1,400 @@
+/*
+ * ip_vs_ftp.c: IPVS ftp application module
+ *
+ * Version:	$Id: ip_vs_ftp.c,v 1.13 2002/09/15 08:14:08 wensong Exp $
+ *
+ * Authors:	Wensong Zhang <wensong@linuxvirtualserver.org>
+ *
+ * Changes:
+ *
+ *
+ *	This program is free software; you can redistribute it and/or
+ *	modify it under the terms of the GNU General Public License
+ *	as published by the Free Software Foundation; either version
+ *	2 of the License, or (at your option) any later version.
+ *
+ * Most code here is taken from ip_masq_ftp.c in kernel 2.2. The difference
+ * is that ip_vs_ftp module handles the reverse direction to ip_masq_ftp.
+ *
+ *		IP_MASQ_FTP ftp masquerading module
+ *
+ * Version:	@(#)ip_masq_ftp.c 0.04   02/05/96
+ *
+ * Author:	Wouter Gadeyne
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/kernel.h>
+#include <linux/skbuff.h>
+#include <linux/in.h>
+#include <linux/ip.h>
+#include <net/protocol.h>
+#include <net/tcp.h>
+
+#include <net/ip_vs.h>
+
+
+#define SERVER_STRING "227 Entering Passive Mode ("
+#define CLIENT_STRING "PORT "
+
+
+/*
+ * List of ports (up to IP_VS_APP_MAX_PORTS) to be handled by helper
+ * First port is set to the default port.
+ */
+static int ports[IP_VS_APP_MAX_PORTS] = {21, 0};
+module_param_array(ports, int, NULL, 0);
+
+/*
+ *	Debug level
+ */
+#ifdef CONFIG_IP_VS_DEBUG
+static int debug=0;
+module_param(debug, int, 0);
+#endif
+
+
+/*	Dummy variable */
+static int ip_vs_ftp_pasv;
+
+
+static int
+ip_vs_ftp_init_conn(struct ip_vs_app *app, struct ip_vs_conn *cp)
+{
+	return 0;
+}
+
+
+static int
+ip_vs_ftp_done_conn(struct ip_vs_app *app, struct ip_vs_conn *cp)
+{
+	return 0;
+}
+
+
+/*
+ * Get <addr,port> from the string "xxx.xxx.xxx.xxx,ppp,ppp", started
+ * with the "pattern" and terminated with the "term" character.
+ * <addr,port> is in network order.
+ */
+static int ip_vs_ftp_get_addrport(char *data, char *data_limit,
+				  const char *pattern, size_t plen, char term,
+				  __u32 *addr, __u16 *port,
+				  char **start, char **end)
+{
+	unsigned char p[6];
+	int i = 0;
+
+	if (data_limit - data < plen) {
+		/* check if there is partial match */
+		if (strnicmp(data, pattern, data_limit - data) == 0)
+			return -1;
+		else
+			return 0;
+	}
+
+	if (strnicmp(data, pattern, plen) != 0) {
+		return 0;
+	}
+	*start = data + plen;
+
+	for (data = *start; *data != term; data++) {
+		if (data == data_limit)
+			return -1;
+	}
+	*end = data;
+
+	memset(p, 0, sizeof(p));
+	for (data = *start; data != *end; data++) {
+		if (*data >= '0' && *data <= '9') {
+			p[i] = p[i]*10 + *data - '0';
+		} else if (*data == ',' && i < 5) {
+			i++;
+		} else {
+			/* unexpected character */
+			return -1;
+		}
+	}
+
+	if (i != 5)
+		return -1;
+
+	*addr = (p[3]<<24) | (p[2]<<16) | (p[1]<<8) | p[0];
+	*port = (p[5]<<8) | p[4];
+	return 1;
+}
+
+
+/*
+ * Look at outgoing ftp packets to catch the response to a PASV command
+ * from the server (inside-to-outside).
+ * When we see one, we build a connection entry with the client address,
+ * client port 0 (unknown at the moment), the server address and the
+ * server port.  Mark the current connection entry as a control channel
+ * of the new entry. All this work is just to make the data connection
+ * can be scheduled to the right server later.
+ *
+ * The outgoing packet should be something like
+ *   "227 Entering Passive Mode (xxx,xxx,xxx,xxx,ppp,ppp)".
+ * xxx,xxx,xxx,xxx is the server address, ppp,ppp is the server port number.
+ */
+static int ip_vs_ftp_out(struct ip_vs_app *app, struct ip_vs_conn *cp,
+			 struct sk_buff **pskb, int *diff)
+{
+	struct iphdr *iph;
+	struct tcphdr *th;
+	char *data, *data_limit;
+	char *start, *end;
+	__u32 from;
+	__u16 port;
+	struct ip_vs_conn *n_cp;
+	char buf[24];		/* xxx.xxx.xxx.xxx,ppp,ppp\000 */
+	unsigned buf_len;
+	int ret;
+
+	*diff = 0;
+
+	/* Only useful for established sessions */
+	if (cp->state != IP_VS_TCP_S_ESTABLISHED)
+		return 1;
+
+	/* Linear packets are much easier to deal with. */
+	if (!ip_vs_make_skb_writable(pskb, (*pskb)->len))
+		return 0;
+
+	if (cp->app_data == &ip_vs_ftp_pasv) {
+		iph = (*pskb)->nh.iph;
+		th = (struct tcphdr *)&(((char *)iph)[iph->ihl*4]);
+		data = (char *)th + (th->doff << 2);
+		data_limit = (*pskb)->tail;
+
+		if (ip_vs_ftp_get_addrport(data, data_limit,
+					   SERVER_STRING,
+					   sizeof(SERVER_STRING)-1, ')',
+					   &from, &port,
+					   &start, &end) != 1)
+			return 1;
+
+		IP_VS_DBG(1-debug, "PASV response (%u.%u.%u.%u:%d) -> "
+			  "%u.%u.%u.%u:%d detected\n",
+			  NIPQUAD(from), ntohs(port), NIPQUAD(cp->caddr), 0);
+
+		/*
+		 * Now update or create an connection entry for it
+		 */
+		n_cp = ip_vs_conn_out_get(iph->protocol, from, port,
+					  cp->caddr, 0);
+		if (!n_cp) {
+			n_cp = ip_vs_conn_new(IPPROTO_TCP,
+					      cp->caddr, 0,
+					      cp->vaddr, port,
+					      from, port,
+					      IP_VS_CONN_F_NO_CPORT,
+					      cp->dest);
+			if (!n_cp)
+				return 0;
+
+			/* add its controller */
+			ip_vs_control_add(n_cp, cp);
+		}
+
+		/*
+		 * Replace the old passive address with the new one
+		 */
+		from = n_cp->vaddr;
+		port = n_cp->vport;
+		sprintf(buf,"%d,%d,%d,%d,%d,%d", NIPQUAD(from),
+			port&255, (port>>8)&255);
+		buf_len = strlen(buf);
+
+		/*
+		 * Calculate required delta-offset to keep TCP happy
+		 */
+		*diff = buf_len - (end-start);
+
+		if (*diff == 0) {
+			/* simply replace it with new passive address */
+			memcpy(start, buf, buf_len);
+			ret = 1;
+		} else {
+			ret = !ip_vs_skb_replace(*pskb, GFP_ATOMIC, start,
+					  end-start, buf, buf_len);
+		}
+
+		cp->app_data = NULL;
+		ip_vs_tcp_conn_listen(n_cp);
+		ip_vs_conn_put(n_cp);
+		return ret;
+	}
+	return 1;
+}
+
+
+/*
+ * Look at incoming ftp packets to catch the PASV/PORT command
+ * (outside-to-inside).
+ *
+ * The incoming packet having the PORT command should be something like
+ *      "PORT xxx,xxx,xxx,xxx,ppp,ppp\n".
+ * xxx,xxx,xxx,xxx is the client address, ppp,ppp is the client port number.
+ * In this case, we create a connection entry using the client address and
+ * port, so that the active ftp data connection from the server can reach
+ * the client.
+ */
+static int ip_vs_ftp_in(struct ip_vs_app *app, struct ip_vs_conn *cp,
+			struct sk_buff **pskb, int *diff)
+{
+	struct iphdr *iph;
+	struct tcphdr *th;
+	char *data, *data_start, *data_limit;
+	char *start, *end;
+	__u32 to;
+	__u16 port;
+	struct ip_vs_conn *n_cp;
+
+	/* no diff required for incoming packets */
+	*diff = 0;
+
+	/* Only useful for established sessions */
+	if (cp->state != IP_VS_TCP_S_ESTABLISHED)
+		return 1;
+
+	/* Linear packets are much easier to deal with. */
+	if (!ip_vs_make_skb_writable(pskb, (*pskb)->len))
+		return 0;
+
+	/*
+	 * Detecting whether it is passive
+	 */
+	iph = (*pskb)->nh.iph;
+	th = (struct tcphdr *)&(((char *)iph)[iph->ihl*4]);
+
+	/* Since there may be OPTIONS in the TCP packet and the HLEN is
+	   the length of the header in 32-bit multiples, it is accurate
+	   to calculate data address by th+HLEN*4 */
+	data = data_start = (char *)th + (th->doff << 2);
+	data_limit = (*pskb)->tail;
+
+	while (data <= data_limit - 6) {
+		if (strnicmp(data, "PASV\r\n", 6) == 0) {
+			/* Passive mode on */
+			IP_VS_DBG(1-debug, "got PASV at %zd of %zd\n",
+				  data - data_start,
+				  data_limit - data_start);
+			cp->app_data = &ip_vs_ftp_pasv;
+			return 1;
+		}
+		data++;
+	}
+
+	/*
+	 * To support virtual FTP server, the scenerio is as follows:
+	 *       FTP client ----> Load Balancer ----> FTP server
+	 * First detect the port number in the application data,
+	 * then create a new connection entry for the coming data
+	 * connection.
+	 */
+	if (ip_vs_ftp_get_addrport(data_start, data_limit,
+				   CLIENT_STRING, sizeof(CLIENT_STRING)-1,
+				   '\r', &to, &port,
+				   &start, &end) != 1)
+		return 1;
+
+	IP_VS_DBG(1-debug, "PORT %u.%u.%u.%u:%d detected\n",
+		  NIPQUAD(to), ntohs(port));
+
+	/* Passive mode off */
+	cp->app_data = NULL;
+
+	/*
+	 * Now update or create a connection entry for it
+	 */
+	IP_VS_DBG(1-debug, "protocol %s %u.%u.%u.%u:%d %u.%u.%u.%u:%d\n",
+		  ip_vs_proto_name(iph->protocol),
+		  NIPQUAD(to), ntohs(port), NIPQUAD(cp->vaddr), 0);
+
+	n_cp = ip_vs_conn_in_get(iph->protocol,
+				 to, port,
+				 cp->vaddr, htons(ntohs(cp->vport)-1));
+	if (!n_cp) {
+		n_cp = ip_vs_conn_new(IPPROTO_TCP,
+				      to, port,
+				      cp->vaddr, htons(ntohs(cp->vport)-1),
+				      cp->daddr, htons(ntohs(cp->dport)-1),
+				      0,
+				      cp->dest);
+		if (!n_cp)
+			return 0;
+
+		/* add its controller */
+		ip_vs_control_add(n_cp, cp);
+	}
+
+	/*
+	 *	Move tunnel to listen state
+	 */
+	ip_vs_tcp_conn_listen(n_cp);
+	ip_vs_conn_put(n_cp);
+
+	return 1;
+}
+
+
+static struct ip_vs_app ip_vs_ftp = {
+	.name =		"ftp",
+	.type =		IP_VS_APP_TYPE_FTP,
+	.protocol =	IPPROTO_TCP,
+	.module =	THIS_MODULE,
+	.incs_list =	LIST_HEAD_INIT(ip_vs_ftp.incs_list),
+	.init_conn =	ip_vs_ftp_init_conn,
+	.done_conn =	ip_vs_ftp_done_conn,
+	.bind_conn =	NULL,
+	.unbind_conn =	NULL,
+	.pkt_out =	ip_vs_ftp_out,
+	.pkt_in =	ip_vs_ftp_in,
+};
+
+
+/*
+ *	ip_vs_ftp initialization
+ */
+static int __init ip_vs_ftp_init(void)
+{
+	int i, ret;
+	struct ip_vs_app *app = &ip_vs_ftp;
+
+	ret = register_ip_vs_app(app);
+	if (ret)
+		return ret;
+
+	for (i=0; i<IP_VS_APP_MAX_PORTS; i++) {
+		if (!ports[i])
+			continue;
+		ret = register_ip_vs_app_inc(app, app->protocol, ports[i]);
+		if (ret)
+			break;
+		IP_VS_DBG(1-debug, "%s: loaded support on port[%d] = %d\n",
+			  app->name, i, ports[i]);
+	}
+
+	if (ret)
+		unregister_ip_vs_app(app);
+
+	return ret;
+}
+
+
+/*
+ *	ip_vs_ftp finish.
+ */
+static void __exit ip_vs_ftp_exit(void)
+{
+	unregister_ip_vs_app(&ip_vs_ftp);
+}
+
+
+module_init(ip_vs_ftp_init);
+module_exit(ip_vs_ftp_exit);
+MODULE_LICENSE("GPL");