[PATCH 07/10] Scrub data of unix socket buffers

[Aruna Balakrishnaiah]

 Iterate from 0 to UNIX_HASH_SIZE and then walk the hlist in
     for (i = 0; i < UNIX_HASH_SIZE; i++) {
         struct list_head *list = &unix_socket_table[i];
         ...
     }
   Walk each non-empty list in unix_socket_table
     struct sock *sk;
     sk_for_each(sk, node, &unix_socket_table[i])


   For each socket iterate over the socket buffers in
   sk_receive_queue and sk_write_queue:

   struct sock {
        ...
        struct sk_buff_head     sk_receive_queue;
        ...
        struct sk_buff_head     sk_write_queue;
        ...
   };

   struct sk_buff_head {
        struct sk_buff  *next;
        struct sk_buff  *prev;
   };

   For each struct sk_buff in the two lists clear the memory referenced
   by skb->data / skb->data_len:

   struct sk_buff {
        ...
        unsigned int            data_len;
        ...
        unsigned char           *data;
        ...
   };

Signed-off-by: Aruna Balakrishnaiah <aruna at linux.vnet.ibm.com>
---
 eppic_scripts/unix_sk_buff.c |   81 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 81 insertions(+)
 create mode 100644 eppic_scripts/unix_sk_buff.c

diff --git a/eppic_scripts/unix_sk_buff.c b/eppic_scripts/unix_sk_buff.c
new file mode 100644
index 0000000..6ab1e6c
--- /dev/null
+++ b/eppic_scripts/unix_sk_buff.c
@@ -0,0 +1,81 @@
+string
+sunix_opt()
+{
+	    return "l";
+}
+
+string
+sunix_usage()
+{
+	    return "\n";
+}
+
+static void
+sunix_showusage()
+{
+	    printf("usage : sunix %s", sunix_usage());
+}
+
+string
+sunix_help()
+{
+	    return "Help";
+}
+
+int
+sunix()
+{
+	int i;
+	int size;
+	struct hlist_head **tab;
+	struct sock_common *off = 0;
+
+	tab = &unix_socket_table;
+
+	for (i = 0; i < 256; i++) {
+		struct hlist_node *pos;
+		struct hlist_node *node;
+		struct hlist_head *tmp;
+
+		tmp = (struct hlist_head *)(tab + i);
+		pos = tmp->first;
+
+		while (pos) {
+			struct sock *sk;
+			struct sk_buff *next;
+			struct sk_buff_head *head;
+
+			sk = (struct sock *)((unsigned long)pos - (unsigned long)&(off->skc_dontcopy_begin));
+
+			head = (struct sk_buff_head *)&(sk->sk_receive_queue);
+			next = (struct sk_buff *)sk->sk_receive_queue.next;
+
+			while (next != head)
+			{
+				struct sk_buff *buff = (struct sk_buff *)next;
+
+				memset((char *)buff->data, 'L', buff->data_len);
+				memset((char *)&(buff->data_len), 'L', 0x4);
+
+				next = buff->next;
+			}
+
+			head = (struct sk_buff_head *)&(sk->sk_write_queue);
+			next = (struct sk_buff *)sk->sk_write_queue.next;
+
+			while (next != head)
+			{
+				struct sk_buff *buff = (struct sk_buff *)next;
+
+				memset((char *)buff->data, 'L', buff->data_len);
+				memset((char *)&(buff->data_len), 'L', 0x4);
+
+			        next = buff->next;
+			}
+
+			node = (struct hlist_node *)((unsigned long)sk + (unsigned long)&(off->skc_dontcopy_begin));
+			pos = node->next;
+		}
+	}
+	return 1;
+}