blob: fed0db170f4fe344533e1e887510f9c4011cd142 [file] [log] [blame]
/*
* Copyright (c) 2016 Samsung Electronics Co., Ltd.
*
* Network Context Metadata Module[NCM]:Implementation.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
/* START_OF_KNOX_NPA */
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/netfilter.h>
#include <linux/ip.h>
#include <linux/ipv6.h>
#include <linux/sctp.h>
#include <linux/miscdevice.h>
#include <linux/uaccess.h>
#include <linux/time.h>
#include <linux/err.h>
#include <linux/netfilter_ipv4.h>
#include <linux/netfilter_ipv6.h>
#include <linux/errno.h>
#include <linux/device.h>
#include <linux/workqueue.h>
#include <linux/sched.h>
#include <linux/mutex.h>
#include <linux/kfifo.h>
#include <linux/kthread.h>
#include <linux/interrupt.h>
#include <linux/poll.h>
#include <linux/udp.h>
#include <linux/sctp.h>
#include <linux/slab.h>
#include <linux/pid.h>
#include <linux/types.h>
#include <linux/socket.h>
#include <linux/in.h>
#include <linux/in6.h>
#include <linux/net.h>
#include <linux/inet.h>
#include <net/sock.h>
#include <net/ncm.h>
#include <net/ip.h>
#include <net/protocol.h>
#include <asm/current.h>
#define SUCCESS 0
#define FAILURE 1
/* fifo size in elements (bytes) */
#define FIFO_SIZE 1024
#define WAIT_TIMEOUT 10000 /*milliseconds */
/* Lock to maintain orderly insertion of elements into kfifo */
static DEFINE_MUTEX(ncm_lock);
static unsigned int ncm_activated_flag = 1;
static unsigned int ncm_deactivated_flag; // default = 0
static unsigned int intermediate_activated_flag = 1;
static unsigned int intermediate_deactivated_flag; // default = 0
static unsigned int device_open_count; // default = 0
static int ncm_activated_type = NCM_FLOW_TYPE_DEFAULT;
static struct nf_hook_ops nfho_ipv4_pr_conntrack;
static struct nf_hook_ops nfho_ipv6_pr_conntrack;
static struct nf_hook_ops nfho_ipv4_li_conntrack;
static struct nf_hook_ops nfho_ipv6_li_conntrack;
static struct workqueue_struct *eWq; // default = 0
wait_queue_head_t ncm_wq;
static atomic_t isNCMEnabled = ATOMIC_INIT(0);
static atomic_t isIntermediateFlowEnabled = ATOMIC_INIT(0);
static unsigned int intermediate_flow_timeout; // default = 0
extern struct knox_socket_metadata knox_socket_metadata;
DECLARE_KFIFO(knox_sock_info, struct knox_socket_metadata, FIFO_SIZE);
/* The function is used to check if ncm feature has been enabled or not; The default value is disabled */
unsigned int check_ncm_flag(void) {
return atomic_read(&isNCMEnabled);
}
EXPORT_SYMBOL(check_ncm_flag);
/* This function is used to check if ncm feature has been enabled with intermediate flow feature */
unsigned int check_intermediate_flag(void) {
return atomic_read(&isIntermediateFlowEnabled);
}
EXPORT_SYMBOL(check_intermediate_flag);
/** The funcation is used to chedk if the kfifo is active or not;
* If the kfifo is active, then the socket metadata would be inserted into the queue which will be read by the user-space;
* By default the kfifo is inactive;
*/
bool kfifo_status(void) {
bool isKfifoActive = false;
if(kfifo_initialized(&knox_sock_info)) {
NCM_LOGD("The fifo queue for ncm was already intialized \n");
isKfifoActive = true;
} else {
NCM_LOGE("The fifo queue for ncm is not intialized \n");
isKfifoActive = false;
}
return isKfifoActive;
}
EXPORT_SYMBOL(kfifo_status);
/** The function is used to insert the socket meta-data into the fifo queue; insertion of data will happen in a seperate kernel thread;
* The meta data information will be collected from the context of the process which originates it;
* If the kfifo is full, then the kfifo is freed before inserting new meta-data;
*/
void insert_data_kfifo(struct work_struct *pwork) {
struct knox_socket_metadata *knox_socket_metadata;
knox_socket_metadata = container_of(pwork,struct knox_socket_metadata,work_kfifo);
if(IS_ERR(knox_socket_metadata)) {
NCM_LOGE("inserting data into the kfifo failed due to unknown error \n");
goto err;
}
if(mutex_lock_interruptible(&ncm_lock)) {
NCM_LOGE("inserting data into the kfifo failed due to an interuppt \n");
goto err;
}
if(kfifo_initialized(&knox_sock_info)) {
if(kfifo_is_full(&knox_sock_info)) {
NCM_LOGD("The kfifo is full and need to free it \n");
kfree(knox_socket_metadata);
} else {
kfifo_in(&knox_sock_info, knox_socket_metadata,1);
kfree(knox_socket_metadata);
}
} else {
kfree(knox_socket_metadata);
}
mutex_unlock(&ncm_lock);
return;
err:
if (knox_socket_metadata != NULL)
kfree(knox_socket_metadata);
return;
}
/** The function is used to insert the socket meta-data into the kfifo in a seperate kernel thread;
* The kernel threads which handles the responsibility of inserting the meta-data into the kfifo is manintained by the workqueue function;
*/
void insert_data_kfifo_kthread(struct knox_socket_metadata* knox_socket_metadata) {
if (knox_socket_metadata != NULL)
{
INIT_WORK(&(knox_socket_metadata->work_kfifo), insert_data_kfifo);
if (!eWq) {
NCM_LOGD("ewq ncmworkqueue not initialized. Data not collected\r\n");
kfree(knox_socket_metadata);
}
if (eWq) {
queue_work(eWq, &(knox_socket_metadata->work_kfifo));
}
}
}
EXPORT_SYMBOL(insert_data_kfifo_kthread);
/* The function is used to check if the caller is system server or not; */
static int is_system_server(void) {
uid_t uid = current_uid().val;
switch(uid) {
case 1000:
return 1;
case 0:
return 1;
default:
break;
}
return 0;
}
/* The function is used to intialize the kfifo */
static void initialize_kfifo(void) {
INIT_KFIFO(knox_sock_info);
if(kfifo_initialized(&knox_sock_info)) {
NCM_LOGD("The kfifo for knox ncm has been initialized \n");
init_waitqueue_head(&ncm_wq);
}
}
/* The function is used to create work queue */
static void initialize_ncmworkqueue(void) {
if (!eWq) {
NCM_LOGD("ewq..Single Thread created\r\n");
eWq = create_workqueue("ncmworkqueue");
}
}
/* The function is ued to free the kfifo */
static void free_kfifo(void) {
if(kfifo_status()) {
NCM_LOGD("The kfifo for knox ncm which was intialized is freed \n");
kfifo_free(&knox_sock_info);
}
}
/* The function is used to update the flag indicating whether the feature has been enabled or not */
static void update_ncm_flag(unsigned int ncmFlag) {
if(ncmFlag == ncm_activated_flag)
atomic_set(&isNCMEnabled, ncm_activated_flag);
else
atomic_set(&isNCMEnabled, ncm_deactivated_flag);
}
/* The function is used to update the flag indicating whether the intermediate flow feature has been enabled or not */
static void update_intermediate_flag(unsigned int ncmIntermediateFlag) {
if (ncmIntermediateFlag == intermediate_activated_flag)
atomic_set(&isIntermediateFlowEnabled, intermediate_activated_flag);
else
atomic_set(&isIntermediateFlowEnabled, intermediate_deactivated_flag);
}
/* The function is used to update the flag indicating start or stop flow */
static void update_ncm_flow_type(int ncmFlowType) {
ncm_activated_type = ncmFlowType;
}
/* This function is used to update the intermediate flow timeout value */
static void update_intermediate_timeout(unsigned int timeout) {
intermediate_flow_timeout = timeout;
}
/* This function is used to get the intermediate flow timeout value */
unsigned int get_intermediate_timeout(void) {
return intermediate_flow_timeout;
}
EXPORT_SYMBOL(get_intermediate_timeout);
/* IPv4 hook function to copy information from struct socket into struct nf_conn during first packet of the network flow */
static unsigned int hook_func_ipv4_out_conntrack(void *priv, struct sk_buff *skb, const struct nf_hook_state *state) {
struct iphdr *ip_header = NULL;
struct tcphdr *tcp_header = NULL;
struct udphdr *udp_header = NULL;
struct nf_conn *ct = NULL;
enum ip_conntrack_info ctinfo;
struct nf_conntrack_tuple *tuple = NULL;
char srcaddr[INET6_ADDRSTRLEN_NAP];
char dstaddr[INET6_ADDRSTRLEN_NAP];
if ( (skb) && (skb->sk) ) {
if ( (skb->sk->knox_pid == INIT_PID_NAP) && (skb->sk->knox_uid == INIT_UID_NAP) && (skb->sk->sk_protocol == IPPROTO_TCP) ) {
return NF_ACCEPT;
}
if ( (skb->sk->sk_protocol == IPPROTO_UDP) || (skb->sk->sk_protocol == IPPROTO_TCP) || (skb->sk->sk_protocol == IPPROTO_ICMP) || (skb->sk->sk_protocol == IPPROTO_SCTP) || (skb->sk->sk_protocol == IPPROTO_ICMPV6) ) {
ct = nf_ct_get(skb, &ctinfo);
if ( (ct) && (!atomic_read(&ct->startFlow)) && (!nf_ct_is_dying(ct)) ) {
tuple = &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple;
if (tuple) {
sprintf(srcaddr,"%pI4",(void *)&tuple->src.u3.ip);
sprintf(dstaddr,"%pI4",(void *)&tuple->dst.u3.ip);
if ( isIpv4AddressEqualsNull(srcaddr, dstaddr) ) {
return NF_ACCEPT;
}
} else {
return NF_ACCEPT;
}
atomic_set(&ct->startFlow, 1);
if ( check_intermediate_flag() ) {
/* Use 'atomic_set(&ct->intermediateFlow, 1); ct->npa_timeout = ((u32)(jiffies)) + (get_intermediate_timeout() * HZ);' if struct nf_conn->timeout is of type u32; */
/* Use 'unsigned long timeout = ct->timeout.expires - jiffies;
if ( (timeout > 0) && ((timeout/HZ) > 5) ) {
atomic_set(&ct->intermediateFlow, 1);
ct->npa_timeout.expires = (jiffies) + (get_intermediate_timeout() * HZ);
add_timer(&ct->npa_timeout);
}'
if struct nf_conn->timeout is of type struct timer_list; */
unsigned long timeout = ct->timeout.expires - jiffies;
if ( (timeout > 0) && ((timeout/HZ) > 5) ) {
atomic_set(&ct->intermediateFlow, 1);
ct->npa_timeout.expires = (jiffies) + (get_intermediate_timeout() * HZ);
add_timer(&ct->npa_timeout);
}
}
ct->knox_uid = skb->sk->knox_uid;
ct->knox_pid = skb->sk->knox_pid;
memcpy(ct->process_name,skb->sk->process_name,sizeof(ct->process_name)-1);
ct->knox_puid = skb->sk->knox_puid;
ct->knox_ppid = skb->sk->knox_ppid;
memcpy(ct->parent_process_name,skb->sk->parent_process_name,sizeof(ct->parent_process_name)-1);
memcpy(ct->domain_name,skb->sk->domain_name,sizeof(ct->domain_name)-1);
if ( (skb->dev) ) {
memcpy(ct->interface_name,skb->dev->name,sizeof(ct->interface_name)-1);
} else {
sprintf(ct->interface_name,"%s","null");
}
ip_header = (struct iphdr *)skb_network_header(skb);
if ( (ip_header) && (ip_header->protocol == IPPROTO_UDP) ) {
udp_header = (struct udphdr *)skb_transport_header(skb);
if (udp_header) {
int udp_payload_size = (ntohs(udp_header->len)) - sizeof(struct udphdr);
if ( (ct->knox_sent + udp_payload_size) > ULLONG_MAX )
ct->knox_sent = ULLONG_MAX;
else
ct->knox_sent = ct->knox_sent + udp_payload_size;
if ( (ntohs(udp_header->dest) == DNS_PORT_NAP) && (ct->knox_uid == INIT_UID_NAP) && (skb->sk->knox_dns_uid > INIT_UID_NAP) ) {
ct->knox_puid = skb->sk->knox_dns_uid;
ct->knox_ppid = skb->sk->knox_dns_pid;
memcpy(ct->parent_process_name,skb->sk->dns_process_name,sizeof(ct->parent_process_name)-1);
}
}
} else if ( (ip_header) && (ip_header->protocol == IPPROTO_TCP) ) {
tcp_header = (struct tcphdr *)skb_transport_header(skb);
if (tcp_header) {
int tcp_payload_size = (ntohs(ip_header->tot_len)) - (ip_header->ihl * 4) - (tcp_header->doff * 4);
if ( (ct->knox_sent + tcp_payload_size) > ULLONG_MAX )
ct->knox_sent = ULLONG_MAX;
else
ct->knox_sent = ct->knox_sent + tcp_payload_size;
if ( (ntohs(tcp_header->dest) == DNS_PORT_NAP) && (ct->knox_uid == INIT_UID_NAP) && (skb->sk->knox_dns_uid > INIT_UID_NAP) ) {
ct->knox_puid = skb->sk->knox_dns_uid;
ct->knox_ppid = skb->sk->knox_dns_pid;
memcpy(ct->parent_process_name,skb->sk->dns_process_name,sizeof(ct->parent_process_name)-1);
}
}
} else {
ct->knox_sent = 0;
}
knox_collect_conntrack_data(ct, NCM_FLOW_TYPE_OPEN, 1);
} else if ( (ct) && (!nf_ct_is_dying(ct)) ) {
ip_header = (struct iphdr *)skb_network_header(skb);
if ( (ip_header) && (ip_header->protocol == IPPROTO_UDP) ) {
udp_header = (struct udphdr *)skb_transport_header(skb);
if (udp_header) {
int udp_payload_size = (ntohs(udp_header->len)) - sizeof(struct udphdr);
if ( (ct->knox_sent + udp_payload_size) > ULLONG_MAX )
ct->knox_sent = ULLONG_MAX;
else
ct->knox_sent = ct->knox_sent + udp_payload_size;
}
} else if ( (ip_header) && (ip_header->protocol == IPPROTO_TCP) ) {
tcp_header = (struct tcphdr *)skb_transport_header(skb);
if (tcp_header) {
int tcp_payload_size = (ntohs(ip_header->tot_len)) - (ip_header->ihl * 4) - (tcp_header->doff * 4);
if ( (ct->knox_sent + tcp_payload_size) > ULLONG_MAX )
ct->knox_sent = ULLONG_MAX;
else
ct->knox_sent = ct->knox_sent + tcp_payload_size;
}
} else {
ct->knox_sent = 0;
}
}
}
}
return NF_ACCEPT;
}
/* IPv6 hook function to copy information from struct socket into struct nf_conn during first packet of the network flow */
static unsigned int hook_func_ipv6_out_conntrack(void *priv, struct sk_buff *skb, const struct nf_hook_state *state) {
struct ipv6hdr *ipv6_header = NULL;
struct tcphdr *tcp_header = NULL;
struct udphdr *udp_header = NULL;
struct nf_conn *ct = NULL;
enum ip_conntrack_info ctinfo;
struct nf_conntrack_tuple *tuple = NULL;
char srcaddr[INET6_ADDRSTRLEN_NAP];
char dstaddr[INET6_ADDRSTRLEN_NAP];
if ( (skb) && (skb->sk) ) {
if ( (skb->sk->knox_pid == INIT_PID_NAP) && (skb->sk->knox_uid == INIT_UID_NAP) && (skb->sk->sk_protocol == IPPROTO_TCP) ) {
return NF_ACCEPT;
}
if ( (skb->sk->sk_protocol == IPPROTO_UDP) || (skb->sk->sk_protocol == IPPROTO_TCP) || (skb->sk->sk_protocol == IPPROTO_ICMP) || (skb->sk->sk_protocol == IPPROTO_SCTP) || (skb->sk->sk_protocol == IPPROTO_ICMPV6) ) {
ct = nf_ct_get(skb, &ctinfo);
if ( (ct) && (!atomic_read(&ct->startFlow)) && (!nf_ct_is_dying(ct)) ) {
tuple = &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple;
if (tuple) {
sprintf(srcaddr,"%pI6",(void *)&tuple->src.u3.ip6);
sprintf(dstaddr,"%pI6",(void *)&tuple->dst.u3.ip6);
if ( isIpv6AddressEqualsNull(srcaddr, dstaddr) ) {
return NF_ACCEPT;
}
} else {
return NF_ACCEPT;
}
atomic_set(&ct->startFlow, 1);
if ( check_intermediate_flag() ) {
/* Use 'atomic_set(&ct->intermediateFlow, 1); ct->npa_timeout = ((u32)(jiffies)) + (get_intermediate_timeout() * HZ);' if struct nf_conn->timeout is of type u32; */
/* Use 'unsigned long timeout = ct->timeout.expires - jiffies;
if ( (timeout > 0) && ((timeout/HZ) > 5) ) {
atomic_set(&ct->intermediateFlow, 1);
ct->npa_timeout.expires = (jiffies) + (get_intermediate_timeout() * HZ);
add_timer(&ct->npa_timeout);
}'
if struct nf_conn->timeout is of type struct timer_list; */
unsigned long timeout = ct->timeout.expires - jiffies;
if ( (timeout > 0) && ((timeout/HZ) > 5) ) {
atomic_set(&ct->intermediateFlow, 1);
ct->npa_timeout.expires = (jiffies) + (get_intermediate_timeout() * HZ);
add_timer(&ct->npa_timeout);
}
}
ct->knox_uid = skb->sk->knox_uid;
ct->knox_pid = skb->sk->knox_pid;
memcpy(ct->process_name,skb->sk->process_name,sizeof(ct->process_name)-1);
ct->knox_puid = skb->sk->knox_puid;
ct->knox_ppid = skb->sk->knox_ppid;
memcpy(ct->parent_process_name,skb->sk->parent_process_name,sizeof(ct->parent_process_name)-1);
memcpy(ct->domain_name,skb->sk->domain_name,sizeof(ct->domain_name)-1);
if ( (skb->dev) ) {
memcpy(ct->interface_name,skb->dev->name,sizeof(ct->interface_name)-1);
} else {
sprintf(ct->interface_name,"%s","null");
}
ipv6_header = (struct ipv6hdr *)skb_network_header(skb);
if ( (ipv6_header) && (ipv6_header->nexthdr == IPPROTO_UDP) ) {
udp_header = (struct udphdr *)skb_transport_header(skb);
if (udp_header) {
int udp_payload_size = (ntohs(udp_header->len)) - sizeof(struct udphdr);
if ( (ct->knox_sent + udp_payload_size) > ULLONG_MAX )
ct->knox_sent = ULLONG_MAX;
else
ct->knox_sent = ct->knox_sent + udp_payload_size;
if ( (ntohs(udp_header->dest) == DNS_PORT_NAP) && (ct->knox_uid == INIT_UID_NAP) && (skb->sk->knox_dns_uid > INIT_UID_NAP) ) {
ct->knox_puid = skb->sk->knox_dns_uid;
ct->knox_ppid = skb->sk->knox_dns_pid;
memcpy(ct->parent_process_name,skb->sk->dns_process_name,sizeof(ct->parent_process_name)-1);
}
}
} else if ( (ipv6_header) && (ipv6_header->nexthdr == IPPROTO_TCP) ) {
tcp_header = (struct tcphdr *)skb_transport_header(skb);
if (tcp_header) {
int tcp_payload_size = (ntohs(ipv6_header->payload_len)) - (tcp_header->doff * 4);
if ( (ct->knox_sent + tcp_payload_size) > ULLONG_MAX )
ct->knox_sent = ULLONG_MAX;
else
ct->knox_sent = ct->knox_sent + tcp_payload_size;
if ( (ntohs(tcp_header->dest) == DNS_PORT_NAP) && (ct->knox_uid == INIT_UID_NAP) && (skb->sk->knox_dns_uid > INIT_UID_NAP) ) {
ct->knox_puid = skb->sk->knox_dns_uid;
ct->knox_ppid = skb->sk->knox_dns_pid;
memcpy(ct->parent_process_name,skb->sk->dns_process_name,sizeof(ct->parent_process_name)-1);
}
}
} else {
ct->knox_sent = 0;
}
knox_collect_conntrack_data(ct, NCM_FLOW_TYPE_OPEN, 2);
} else if ( (ct) && (!nf_ct_is_dying(ct)) ) {
ipv6_header = (struct ipv6hdr *)skb_network_header(skb);
if ( (ipv6_header) && (ipv6_header->nexthdr == IPPROTO_UDP) ) {
udp_header = (struct udphdr *)skb_transport_header(skb);
if (udp_header) {
int udp_payload_size = (ntohs(udp_header->len)) - sizeof(struct udphdr);
if ( (ct->knox_sent + udp_payload_size) > ULLONG_MAX )
ct->knox_sent = ULLONG_MAX;
else
ct->knox_sent = ct->knox_sent + udp_payload_size;
}
} else if ( (ipv6_header) && (ipv6_header->nexthdr == IPPROTO_TCP) ) {
tcp_header = (struct tcphdr *)skb_transport_header(skb);
if (tcp_header) {
int tcp_payload_size = (ntohs(ipv6_header->payload_len)) - (tcp_header->doff * 4);
if ( (ct->knox_sent + tcp_payload_size) > ULLONG_MAX )
ct->knox_sent = ULLONG_MAX;
else
ct->knox_sent = ct->knox_sent + tcp_payload_size;
}
} else {
ct->knox_sent = 0;
}
}
}
}
return NF_ACCEPT;
}
static unsigned int hook_func_ipv4_in_conntrack(void *priv, struct sk_buff *skb, const struct nf_hook_state *state) {
struct iphdr *ip_header = NULL;
struct tcphdr *tcp_header = NULL;
struct udphdr *udp_header = NULL;
struct nf_conn *ct = NULL;
enum ip_conntrack_info ctinfo;
if (skb){
ip_header = (struct iphdr *)skb_network_header(skb);
if ( (ip_header) && (ip_header->protocol == IPPROTO_TCP || ip_header->protocol == IPPROTO_UDP || ip_header->protocol == IPPROTO_SCTP || ip_header->protocol == IPPROTO_ICMP || ip_header->protocol == IPPROTO_ICMPV6) ) {
ct = nf_ct_get(skb, &ctinfo);
if ( (ct) && (!nf_ct_is_dying(ct)) ) {
if (ip_header->protocol == IPPROTO_TCP) {
tcp_header = (struct tcphdr *)skb_transport_header(skb);
if (tcp_header) {
int tcp_payload_size = (ntohs(ip_header->tot_len)) - (ip_header->ihl * 4) - (tcp_header->doff * 4);
if ( (ct->knox_recv + tcp_payload_size) > ULLONG_MAX )
ct->knox_recv = ULLONG_MAX;
else
ct->knox_recv = ct->knox_recv + tcp_payload_size;
}
} else if (ip_header->protocol == IPPROTO_UDP) {
udp_header = (struct udphdr *)skb_transport_header(skb);
if (udp_header) {
int udp_payload_size = (ntohs(udp_header->len)) - sizeof(struct udphdr);
if ( (ct->knox_recv + udp_payload_size) > ULLONG_MAX )
ct->knox_recv = ULLONG_MAX;
else
ct->knox_recv = ct->knox_recv + udp_payload_size;
}
} else {
ct->knox_recv = 0;
}
}
}
}
return NF_ACCEPT;
}
static unsigned int hook_func_ipv6_in_conntrack(void *priv, struct sk_buff *skb, const struct nf_hook_state *state) {
struct ipv6hdr *ipv6_header = NULL;
struct tcphdr *tcp_header = NULL;
struct udphdr *udp_header = NULL;
struct nf_conn *ct = NULL;
enum ip_conntrack_info ctinfo;
if (skb){
ipv6_header = (struct ipv6hdr *)skb_network_header(skb);
if ( (ipv6_header) && (ipv6_header->nexthdr == IPPROTO_TCP || ipv6_header->nexthdr == IPPROTO_UDP || ipv6_header->nexthdr == IPPROTO_SCTP || ipv6_header->nexthdr == IPPROTO_ICMP || ipv6_header->nexthdr == IPPROTO_ICMPV6) ) {
ct = nf_ct_get(skb, &ctinfo);
if ( (ct) && (!nf_ct_is_dying(ct)) ) {
if (ipv6_header->nexthdr == IPPROTO_TCP) {
tcp_header = (struct tcphdr *)skb_transport_header(skb);
if (tcp_header) {
int tcp_payload_size = (ntohs(ipv6_header->payload_len)) - (tcp_header->doff * 4);
if ( (ct->knox_recv + tcp_payload_size) > ULLONG_MAX )
ct->knox_recv = ULLONG_MAX;
else
ct->knox_recv = ct->knox_recv + tcp_payload_size;
}
} else if (ipv6_header->nexthdr == IPPROTO_UDP) {
udp_header = (struct udphdr *)skb_transport_header(skb);
if (udp_header) {
int udp_payload_size = (ntohs(udp_header->len)) - sizeof(struct udphdr);
if ( (ct->knox_recv + udp_payload_size) > ULLONG_MAX )
ct->knox_recv = ULLONG_MAX;
else
ct->knox_recv = ct->knox_recv + udp_payload_size;
}
} else {
ct->knox_recv = 0;
}
}
}
}
return NF_ACCEPT;
}
/* The fuction registers to listen for packets in the post-routing chain to collect detail; */
static void registerNetfilterHooks(void) {
nfho_ipv4_pr_conntrack.hook = hook_func_ipv4_out_conntrack;
nfho_ipv4_pr_conntrack.hooknum = NF_INET_POST_ROUTING;
nfho_ipv4_pr_conntrack.pf = PF_INET;
nfho_ipv4_pr_conntrack.priority = NF_IP_PRI_LAST;
nfho_ipv6_pr_conntrack.hook = hook_func_ipv6_out_conntrack;
nfho_ipv6_pr_conntrack.hooknum = NF_INET_POST_ROUTING;
nfho_ipv6_pr_conntrack.pf = PF_INET6;
nfho_ipv6_pr_conntrack.priority = NF_IP6_PRI_LAST;
nfho_ipv4_li_conntrack.hook = hook_func_ipv4_in_conntrack;
nfho_ipv4_li_conntrack.hooknum = NF_INET_LOCAL_IN;
nfho_ipv4_li_conntrack.pf = PF_INET;
nfho_ipv4_li_conntrack.priority = NF_IP_PRI_LAST;
nfho_ipv6_li_conntrack.hook = hook_func_ipv6_in_conntrack;
nfho_ipv6_li_conntrack.hooknum = NF_INET_LOCAL_IN;
nfho_ipv6_li_conntrack.pf = PF_INET6;
nfho_ipv6_li_conntrack.priority = NF_IP6_PRI_LAST;
/* For kernel version above 4.13
nf_unregister_net_hook(&init_net,&nfho_ipv4_pr_conntrack);
nf_unregister_net_hook(&init_net,&nfho_ipv6_pr_conntrack);
nf_unregister_net_hook(&init_net,&nfho_ipv4_li_conntrack);
nf_unregister_net_hook(&init_net,&nfho_ipv6_li_conntrack); */
/* For kernel version below 4.13 */
nf_register_hook(&nfho_ipv4_pr_conntrack);
nf_register_hook(&nfho_ipv6_pr_conntrack);
nf_register_hook(&nfho_ipv4_li_conntrack);
nf_register_hook(&nfho_ipv6_li_conntrack);
}
/* The function un-registers the netfilter hook */
static void unregisterNetFilterHooks(void) {
/* For kernel version above 4.13
nf_unregister_net_hook(&init_net,&nfho_ipv4_pr_conntrack);
nf_unregister_net_hook(&init_net,&nfho_ipv6_pr_conntrack);
nf_unregister_net_hook(&init_net,&nfho_ipv4_li_conntrack);
nf_unregister_net_hook(&init_net,&nfho_ipv6_li_conntrack); */
/* For kernel version below 4.13 */
nf_unregister_hook(&nfho_ipv4_pr_conntrack);
nf_unregister_hook(&nfho_ipv6_pr_conntrack);
nf_unregister_hook(&nfho_ipv4_li_conntrack);
nf_unregister_hook(&nfho_ipv6_li_conntrack);
}
/* Function to collect the conntrack meta-data information. This function is called from ncm.c during the flows first send data and nf_conntrack_core.c when flow is removed. */
void knox_collect_conntrack_data(struct nf_conn *ct, int startStop, int where) {
if ( check_ncm_flag() && (ncm_activated_type == startStop || ncm_activated_type == NCM_FLOW_TYPE_ALL) ) {
struct knox_socket_metadata *ksm = kzalloc(sizeof(struct knox_socket_metadata), GFP_ATOMIC);
struct nf_conntrack_tuple *tuple = NULL;
struct timespec close_timespec;
if (ksm == NULL) {
printk("kzalloc atomic memory allocation failed\n");
return;
}
ksm->knox_uid = ct->knox_uid;
ksm->knox_pid = ct->knox_pid;
memcpy(ksm->process_name, ct->process_name, sizeof(ksm->process_name)-1);
ksm->trans_proto = nf_ct_protonum(ct);
tuple = &ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple;
if (tuple != NULL) {
if (nf_ct_l3num(ct) == IPV4_FAMILY_NAP) {
sprintf(ksm->srcaddr,"%pI4",(void *)&tuple->src.u3.ip);
sprintf(ksm->dstaddr,"%pI4",(void *)&tuple->dst.u3.ip);
} else if (nf_ct_l3num(ct) == IPV6_FAMILY_NAP) {
sprintf(ksm->srcaddr,"%pI6",(void *)&tuple->src.u3.ip6);
sprintf(ksm->dstaddr,"%pI6",(void *)&tuple->dst.u3.ip6);
}
if (nf_ct_protonum(ct) == IPPROTO_UDP) {
ksm->srcport = ntohs(tuple->src.u.udp.port);
ksm->dstport = ntohs(tuple->dst.u.udp.port);
} else if (nf_ct_protonum(ct) == IPPROTO_TCP) {
ksm->srcport = ntohs(tuple->src.u.tcp.port);
ksm->dstport = ntohs(tuple->dst.u.tcp.port);
} else if (nf_ct_protonum(ct) == IPPROTO_SCTP) {
ksm->srcport = ntohs(tuple->src.u.sctp.port);
ksm->dstport = ntohs(tuple->dst.u.sctp.port);
} else {
ksm->srcport = 0;
ksm->dstport = 0;
}
}
memcpy(ksm->domain_name, ct->domain_name, sizeof(ksm->domain_name)-1);
ksm->open_time = ct->open_time;
if (startStop == NCM_FLOW_TYPE_OPEN) {
ksm->close_time = 0;
} else if (startStop == NCM_FLOW_TYPE_CLOSE) {
close_timespec = current_kernel_time();
ksm->close_time = close_timespec.tv_sec;
} else if (startStop == NCM_FLOW_TYPE_INTERMEDIATE) {
close_timespec = current_kernel_time();
ksm->close_time = close_timespec.tv_sec;
}
ksm->knox_puid = ct->knox_puid;
ksm->knox_ppid = ct->knox_ppid;
memcpy(ksm->parent_process_name, ct->parent_process_name, sizeof(ksm->parent_process_name)-1);
if ( (nf_ct_protonum(ct) == IPPROTO_UDP) || (nf_ct_protonum(ct) == IPPROTO_TCP) || (nf_ct_protonum(ct) == IPPROTO_SCTP) ) {
ksm->knox_sent = ct->knox_sent;
ksm->knox_recv = ct->knox_recv;
} else {
ksm->knox_sent = 0;
ksm->knox_recv = 0;
}
if (ksm->dstport == DNS_PORT_NAP && ksm->knox_uid > INIT_UID_NAP) {
ksm->knox_uid_dns = ksm->knox_uid;
} else {
ksm->knox_uid_dns = ksm->knox_puid;
}
memcpy(ksm->interface_name, ct->interface_name, sizeof(ksm->interface_name)-1);
if (startStop == NCM_FLOW_TYPE_OPEN) {
ksm->flow_type = 1;
} else if (startStop == NCM_FLOW_TYPE_CLOSE) {
ksm->flow_type = 2;
} else if (startStop == NCM_FLOW_TYPE_INTERMEDIATE) {
ksm->flow_type = 3;
} else {
ksm->flow_type = 0;
}
insert_data_kfifo_kthread(ksm);
}
}
EXPORT_SYMBOL(knox_collect_conntrack_data);
/* The function opens the char device through which the userspace reads the socket meta-data information */
static int ncm_open(struct inode *inode, struct file *file) {
NCM_LOGD("ncm_open is being called. \n");
if ( !(IS_ENABLED(CONFIG_NF_CONNTRACK)) ) {
NCM_LOGE("ncm_open failed:Trying to open in device conntrack module is not enabled \n");
return -EACCES;
}
if(!is_system_server()) {
NCM_LOGE("ncm_open failed:Caller is a non system process with uid %u \n",(current_uid().val));
return -EACCES;
}
if (device_open_count) {
NCM_LOGE("ncm_open failed:The device is already in open state \n");
return -EBUSY;
}
device_open_count++;
try_module_get(THIS_MODULE);
return SUCCESS;
}
#ifdef CONFIG_64BIT
static ssize_t ncm_copy_data_user_64(char __user * buf,size_t count) {
struct knox_socket_metadata kcm = {0};
struct knox_user_socket_metadata user_copy = {0};
unsigned long copied;
int read = 0;
if(mutex_lock_interruptible(&ncm_lock)) {
NCM_LOGE("ncm_copy_data_user failed:Signal interuption \n");
return 0;
}
read = kfifo_out(&knox_sock_info, &kcm,1);
mutex_unlock(&ncm_lock);
if(read == 0) {
return 0;
}
user_copy.srcport = kcm.srcport;
user_copy.dstport = kcm.dstport;
user_copy.trans_proto = kcm.trans_proto;
user_copy.knox_sent = kcm.knox_sent;
user_copy.knox_recv = kcm.knox_recv;
user_copy.knox_uid = kcm.knox_uid;
user_copy.knox_pid = kcm.knox_pid;
user_copy.knox_puid = kcm.knox_puid;
user_copy.open_time = kcm.open_time;
user_copy.close_time = kcm.close_time;
user_copy.knox_uid_dns = kcm.knox_uid_dns;
user_copy.knox_ppid = kcm.knox_ppid;
user_copy.flow_type = kcm.flow_type;
memcpy(user_copy.srcaddr,kcm.srcaddr,sizeof(user_copy.srcaddr));
memcpy(user_copy.dstaddr,kcm.dstaddr,sizeof(user_copy.dstaddr));
memcpy(user_copy.process_name,kcm.process_name,sizeof(user_copy.process_name));
memcpy(user_copy.parent_process_name,kcm.parent_process_name,sizeof(user_copy.parent_process_name));
memcpy(user_copy.domain_name,kcm.domain_name,sizeof(user_copy.domain_name)-1);
memcpy(user_copy.interface_name, kcm.interface_name, sizeof(user_copy.interface_name)-1);
copied = copy_to_user(buf, &user_copy, sizeof(struct knox_user_socket_metadata));
return count;
}
#else
static ssize_t ncm_copy_data_user(char __user * buf,size_t count) {
struct knox_socket_metadata *kcm = NULL;
struct knox_user_socket_metadata user_copy = {0};
unsigned long copied;
int read = 0;
if(mutex_lock_interruptible(&ncm_lock)) {
NCM_LOGE("ncm_copy_data_user failed:Signal interuption \n");
return 0;
}
kcm = kzalloc(sizeof (struct knox_socket_metadata), GFP_KERNEL);
if (kcm == NULL) {
mutex_unlock(&ncm_lock);
return 0;
}
read = kfifo_out(&knox_sock_info, kcm,1);
mutex_unlock(&ncm_lock);
if(read == 0) {
kfree(kcm);
return 0;
}
user_copy.srcport = kcm->srcport;
user_copy.dstport = kcm->dstport;
user_copy.trans_proto = kcm->trans_proto;
user_copy.knox_sent = kcm->knox_sent;
user_copy.knox_recv = kcm->knox_recv;
user_copy.knox_uid = kcm->knox_uid;
user_copy.knox_pid = kcm->knox_pid;
user_copy.knox_puid = kcm->knox_puid;
user_copy.open_time = kcm->open_time;
user_copy.close_time = kcm->close_time;
user_copy.knox_uid_dns = kcm->knox_uid_dns;
user_copy.knox_ppid = kcm->knox_ppid;
user_copy.flow_type = kcm->flow_type;
memcpy(user_copy.srcaddr,kcm->srcaddr,sizeof(user_copy.srcaddr));
memcpy(user_copy.dstaddr,kcm->dstaddr,sizeof(user_copy.dstaddr));
memcpy(user_copy.process_name,kcm->process_name,sizeof(user_copy.process_name));
memcpy(user_copy.parent_process_name,kcm->parent_process_name,sizeof(user_copy.parent_process_name));
memcpy(user_copy.domain_name,kcm->domain_name,sizeof(user_copy.domain_name)-1);
memcpy(user_copy.interface_name, kcm->interface_name, sizeof(user_copy.interface_name)-1);
copied = copy_to_user(buf,&user_copy,sizeof(struct knox_user_socket_metadata));
kfree(kcm);
return count;
}
#endif
/* The function writes the socket meta-data to the user-space */
static ssize_t ncm_read(struct file *file, char __user *buf, size_t count, loff_t *off) {
if(!is_system_server()) {
NCM_LOGE("ncm_read failed:Caller is a non system process with uid %u \n",(current_uid().val));
return -EACCES;
}
if (!eWq) {
NCM_LOGD("ewq..Single Thread created\r\n");
eWq = create_workqueue("ncmworkqueue");
}
#ifdef CONFIG_64BIT
return ncm_copy_data_user_64(buf,count);
#else
return ncm_copy_data_user(buf,count);
#endif
return 0;
}
static ssize_t ncm_write(struct file *file, const char __user *buf, size_t count, loff_t *off) {
char intermediate_string[6];
int intermediate_value = 0;
int ret = 0;
if (!is_system_server()) {
NCM_LOGE("ncm_write failed:Caller is a non system process with uid %u \n", (current_uid().val));
return -EACCES;
}
memset(intermediate_string,'\0',sizeof(intermediate_string));
ret = copy_from_user(intermediate_string,buf,sizeof(intermediate_string)-1);
if(ret == 0)
{
intermediate_value = simple_strtol(intermediate_string, NULL, 10);
if (intermediate_value > 0) {
update_intermediate_timeout(intermediate_value);
update_intermediate_flag(intermediate_activated_flag);
return strlen(intermediate_string);
}
}
return intermediate_value;
}
/* The function closes the char device */
static int ncm_close(struct inode *inode, struct file *file) {
NCM_LOGD("ncm_close is being called \n");
if(!is_system_server()) {
NCM_LOGE("ncm_close failed:Caller is a non system process with uid %u \n",(current_uid().val));
return -EACCES;
}
device_open_count--;
module_put(THIS_MODULE);
if(!check_ncm_flag()) {
NCM_LOGD("ncm_close success: The device was already in closed state \n");
return SUCCESS;
}
update_ncm_flag(ncm_deactivated_flag);
free_kfifo();
unregisterNetFilterHooks();
return SUCCESS;
}
/* The function sets the flag which indicates whether the ncm feature needs to be enabled or disabled */
static long ncm_ioctl_evt(struct file *file, unsigned int cmd, unsigned long arg) {
if (!is_system_server()) {
NCM_LOGE("ncm_ioctl_evt failed:Caller is a non system process with uid %u \n", (current_uid().val));
return -EACCES;
}
switch (cmd) {
case NCM_ACTIVATED_ALL: {
NCM_LOGD("ncm_ioctl_evt is being NCM_ACTIVATED with the ioctl command %u \n", cmd);
if (check_ncm_flag())
return SUCCESS;
registerNetfilterHooks();
initialize_kfifo();
initialize_ncmworkqueue();
update_ncm_flag(ncm_activated_flag);
update_ncm_flow_type(NCM_FLOW_TYPE_ALL);
break;
}
case NCM_ACTIVATED_OPEN: {
NCM_LOGD("ncm_ioctl_evt is being NCM_ACTIVATED with the ioctl command %u \n", cmd);
if (check_ncm_flag())
return SUCCESS;
update_intermediate_timeout(0);
update_intermediate_flag(intermediate_deactivated_flag);
registerNetfilterHooks();
initialize_kfifo();
initialize_ncmworkqueue();
update_ncm_flag(ncm_activated_flag);
update_ncm_flow_type(NCM_FLOW_TYPE_OPEN);
break;
}
case NCM_ACTIVATED_CLOSE: {
NCM_LOGD("ncm_ioctl_evt is being NCM_ACTIVATED with the ioctl command %u \n", cmd);
if (check_ncm_flag())
return SUCCESS;
update_intermediate_timeout(0);
update_intermediate_flag(intermediate_deactivated_flag);
registerNetfilterHooks();
initialize_kfifo();
initialize_ncmworkqueue();
update_ncm_flag(ncm_activated_flag);
update_ncm_flow_type(NCM_FLOW_TYPE_CLOSE);
break;
}
case NCM_DEACTIVATED: {
NCM_LOGD("ncm_ioctl_evt is being NCM_DEACTIVATED with the ioctl command %u \n", cmd);
if (!check_ncm_flag())
return SUCCESS;
update_intermediate_flag(intermediate_deactivated_flag);
update_ncm_flow_type(NCM_FLOW_TYPE_DEFAULT);
update_ncm_flag(ncm_deactivated_flag);
free_kfifo();
unregisterNetFilterHooks();
update_intermediate_timeout(0);
break;
}
case NCM_GETVERSION: {
NCM_LOGD("ncm_ioctl_evt is being NCM_GETVERSION with the ioctl command %u \n", cmd);
return NCM_VERSION;
break;
}
case NCM_MATCH_VERSION: {
NCM_LOGD("ncm_ioctl_evt is being NCM_MATCH_VERSION with the ioctl command %u \n", cmd);
return sizeof(struct knox_user_socket_metadata);
break;
}
default:
break;
}
return SUCCESS;
}
static unsigned int ncm_poll(struct file *file, poll_table *pt) {
int mask = 0;
int ret = 0;
if (kfifo_is_empty(&knox_sock_info)) {
ret = wait_event_interruptible_timeout(ncm_wq,!kfifo_is_empty(&knox_sock_info), msecs_to_jiffies(WAIT_TIMEOUT));
switch(ret) {
case -ERESTARTSYS:
mask = -EINTR;
break;
case 0:
mask = 0;
break;
case 1:
mask |= POLLIN | POLLRDNORM;
break;
default:
mask |= POLLIN | POLLRDNORM;
break;
}
return mask;
} else {
mask |= POLLIN | POLLRDNORM;
}
return mask;
}
static const struct file_operations ncm_fops = {
.owner = THIS_MODULE,
.open = ncm_open,
.read = ncm_read,
.write = ncm_write,
.release = ncm_close,
.unlocked_ioctl = ncm_ioctl_evt,
.compat_ioctl = ncm_ioctl_evt,
.poll = ncm_poll,
};
struct miscdevice ncm_misc_device = {
.minor = MISC_DYNAMIC_MINOR,
.name = "ncm_dev",
.fops = &ncm_fops,
};
static int __init ncm_init(void) {
int ret;
ret = misc_register(&ncm_misc_device);
if (unlikely(ret)) {
NCM_LOGE("failed to register ncm misc device!\n");
return ret;
}
NCM_LOGD("Network Context Metadata Module: initialized\n");
return SUCCESS;
}
static void __exit ncm_exit(void) {
misc_deregister(&ncm_misc_device);
NCM_LOGD("Network Context Metadata Module: unloaded\n");
}
module_init(ncm_init)
module_exit(ncm_exit)
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Network Context Metadata Module:");
/* END_OF_KNOX_NPA */