[Devel] [PATCH RHEL7 COMMIT] vzprivnet: Add the classifier proc file

[Konstantin Khorenko]

The commit is pushed to "branch-rh7-3.10.0-327.10.1.vz7.12.x-ovz" and will appear at https://src.openvz.org/scm/ovz/vzkernel.git
after rh7-3.10.0-327.10.1.vz7.12.3
------>
commit f074493158a4e79186cf72bbe559b4196244e045
Author: Pavel Tikhomirov <ptikhomirov at virtuozzo.com>
Date:   Thu Mar 24 19:53:31 2016 +0400

    vzprivnet: Add the classifier proc file
    
    changes:
    1) replace NIPQUAD_FMT with %pI4 in sparse_seq_show part2
    
    Port diff-vz-privnet-classifier-helper
      vzprivnet: Add the classifier proc file
    
      Writing an IP to this file and reading from it then will
      result in seeing of which rule was matched on it.
    
      For debugging purposes.
    
      Signed-off-by: Pavel Emelyanov <xemul at paralles.com>
    
    Signed-off-by: Pavel Tikhomirov <ptikhomirov at virtuozzo.com>
---
 net/ipv4/netfilter/ip_vzprivnet.c | 88 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 88 insertions(+)

diff --git a/net/ipv4/netfilter/ip_vzprivnet.c b/net/ipv4/netfilter/ip_vzprivnet.c
index 8eaa421..0142fc3 100644
--- a/net/ipv4/netfilter/ip_vzprivnet.c
+++ b/net/ipv4/netfilter/ip_vzprivnet.c
@@ -859,6 +859,86 @@ static struct file_operations proc_stat_ops = {
 	.release = seq_release,
 };
 
+static char sample_ip[16];
+
+static ssize_t classify_write(struct file * file, const char __user *buf,
+			    size_t count, loff_t *ppos)
+{
+	int len;
+	char *tmp;
+
+	len = count;
+	if (len >= sizeof(sample_ip))
+		len = sizeof(sample_ip) - 1;
+
+	if (copy_from_user(sample_ip, buf, len))
+		return -EFAULT;
+
+	sample_ip[len] = '\0';
+	tmp = strchr(sample_ip, '\n');
+	if (tmp)
+		*tmp = '\0';
+
+	return count;
+}
+
+static int classify_seq_show(struct seq_file *s, void *v)
+{
+	u32 ip;
+	struct vzprivnet_range *pnr;
+
+	seq_printf(s, "%s: ", sample_ip);
+
+	if (!in4_pton(sample_ip, sizeof(sample_ip), (u8 *)&ip, -1, NULL)) {
+		seq_puts(s, "invalid IP\n");
+		return 0;
+	}
+
+	read_lock(&vzprivlock);
+	pnr = tree_search(&entries_root, ip);
+	if (pnr != NULL) {
+		struct vzprivnet_sparse *pns;
+
+		pns = container_of(pnr->pn, struct vzprivnet_sparse, pn);
+		seq_printf(s, "net %u, ", pns->netid);
+		seq_printf(s, "rule %pI4", &pnr->netip);
+		if (~pnr->rmask != 0)
+			seq_printf(s, "/%u", to_prefix(pnr->rmask));
+		seq_putc(s, '\n');
+
+		goto out;
+	}
+
+	pnr = legacy_search(ip);
+	if (pnr != NULL) {
+		seq_printf(s, "legacy %pI4/%u/%u\n",
+				&pnr->netip,
+				to_prefix(pnr->rmask),
+				to_prefix(pnr->pn->nmask));
+
+		goto out;
+	}
+
+	seq_printf(s, "internet\n");
+out:
+	read_unlock(&vzprivlock);
+	return 0;
+}
+
+static int classify_seq_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, &classify_seq_show, NULL);
+}
+
+static struct file_operations proc_classify_ops = {
+	.owner   = THIS_MODULE,
+	.open    = classify_seq_open,
+	.read    = seq_read,
+	.llseek  = seq_lseek,
+	.release = seq_release,
+	.write	 = classify_write,
+};
+
 static struct proc_dir_entry *vzpriv_proc_dir;
 
 static int __init iptable_vzprivnet_init(void)
@@ -885,6 +965,11 @@ static int __init iptable_vzprivnet_init(void)
 	if (proc == NULL)
 		goto err_stat;
 
+	proc = proc_create("classify", 0644,
+			vzpriv_proc_dir, &proc_classify_ops);
+	if (proc == NULL)
+		goto err_classify;
+
 	proc = proc_symlink(VZPRIV_PROCNAME, init_net.proc_net, "/proc/vz/privnet/legacy");
 	if (proc == NULL)
 		goto err_link;
@@ -898,6 +983,8 @@ static int __init iptable_vzprivnet_init(void)
 err_reg:
 	remove_proc_entry(VZPRIV_PROCNAME, init_net.proc_net);
 err_link:
+	remove_proc_entry("classify", vzpriv_proc_dir);
+err_classify:
 	remove_proc_entry("stat", vzpriv_proc_dir);
 err_stat:
 	remove_proc_entry("sparse", vzpriv_proc_dir);
@@ -913,6 +1000,7 @@ static void __exit iptable_vzprivnet_exit(void)
 {
 	nf_unregister_hook(&vzprivnet_ops);
 	remove_proc_entry(VZPRIV_PROCNAME, init_net.proc_net);
+	remove_proc_entry("classify", vzpriv_proc_dir);
 	remove_proc_entry("stat", vzpriv_proc_dir);
 	remove_proc_entry("sparse", vzpriv_proc_dir);
 	remove_proc_entry("legacy", vzpriv_proc_dir);