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natflow_urllogger.c
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/*
* Author: Chen Minqiang <ptpt52@gmail.com>
* Date : Tue, 22 Jun 2021 22:50:41 +0800
*/
#include <linux/ctype.h>
#include <linux/cdev.h>
#include <linux/device.h>
#include <linux/fs.h>
#include <linux/seq_file.h>
#include <linux/if_ether.h>
#include <linux/if_packet.h>
#include <linux/init.h>
#include <linux/ip.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/vmalloc.h>
#include <linux/module.h>
#include <linux/netdevice.h>
#include <linux/netfilter.h>
#include <linux/inetdevice.h>
#include <linux/skbuff.h>
#include <linux/socket.h>
#include <linux/string.h>
#include <linux/syscalls.h>
#include <linux/tcp.h>
#include <linux/uaccess.h>
#include <linux/unistd.h>
#include <linux/version.h>
#include <linux/mman.h>
#include <linux/spinlock.h>
#include <linux/rcupdate.h>
#include <linux/highmem.h>
#include <net/netfilter/nf_conntrack.h>
#include <linux/netfilter/ipset/ip_set.h>
#include <net/ip.h>
#include <net/tcp.h>
#include <net/udp.h>
#include <net/ip6_checksum.h>
#include "natflow_common.h"
#include "natflow_urllogger.h"
static int urllogger_major = 0;
static int urllogger_minor = 0;
static struct cdev urllogger_cdev;
const char *urllogger_dev_name = "urllogger_queue";
static struct class *urllogger_class;
static struct device *urllogger_dev;
static inline ssize_t urlinfo_copy_host_tolower(unsigned char *dst, unsigned char *src, ssize_t n)
{
ssize_t i = 0;
for (; i < n; i++) {
if (src[i] == '/')
break;
if (src[i] >= 'A' && src[i] <= 'Z')
dst[i] = src[i] - 'A' + 'a';
else
dst[i] = src[i];
}
memcpy(dst + i, src + i, n - i);
return i;
}
struct urlinfo {
struct list_head list;
#define URLINFO_NOW ((jiffies - INITIAL_JIFFIES) / HZ)
#define TIMESTAMP_FREQ 10
unsigned int timestamp;
union {
__be32 sip;
union nf_inet_addr sipv6;
};
union {
__be32 dip;
union nf_inet_addr dipv6;
};
__be16 sport;
__be16 dport;
unsigned char mac[ETH_ALEN];
#define URLINFO_HTTPS 0x01
#define URLINFO_IPV6 0x80
unsigned char flags;
#define NATFLOW_HTTP_NONE 0
#define NATFLOW_HTTP_GET 1
#define NATFLOW_HTTP_POST 2
#define NATFLOW_HTTP_HEAD 3
unsigned char http_method;
unsigned short hits;
unsigned short data_len;
unsigned short host_len;
unsigned char acl_idx;
#define URLINFO_ACL_ACTION_RECORD 0
#define URLINFO_ACL_ACTION_DROP 1
#define URLINFO_ACL_ACTION_RESET 2
#define URLINFO_ACL_ACTION_REDIRECT 3
unsigned char acl_action;
unsigned char data[0];
};
#define __URLINFO_ALIGN 64
static const char *NATFLOW_http_method[] = {
[NATFLOW_HTTP_NONE] = "NONE",
[NATFLOW_HTTP_GET] = "GET",
[NATFLOW_HTTP_POST] = "POST",
[NATFLOW_HTTP_HEAD] = "HEAD",
};
static inline void urlinfo_release(struct urlinfo *url)
{
kfree(url);
}
/*
tuple_type:
0: dir0-src dir0-dst
1: dir0-src dir1-src
2: dir1-dst dir1-src
*/
static unsigned int urllogger_store_tuple_type = 0;
static unsigned int urllogger_store_timestamp_freq = TIMESTAMP_FREQ;
static unsigned int urllogger_store_enable = 0;
static unsigned int urllogger_store_memsize_limit = 1024 * 1024 * 10;
static unsigned int urllogger_store_count_limit = 10000;
static unsigned int urllogger_store_memsize = 0;
static unsigned int urllogger_store_count = 0;
static LIST_HEAD(urllogger_store_list);
static DEFINE_SPINLOCK(urllogger_store_lock);
static void urllogger_store_record(struct urlinfo *url)
{
struct urlinfo *url_i;
struct list_head *pos;
spin_lock(&urllogger_store_lock);
list_for_each_prev(pos, &urllogger_store_list) {
url_i = list_entry(pos, struct urlinfo, list);
/* merge the duplicate url request in 10s */
if (uintmindiff(url_i->timestamp, url->timestamp) > urllogger_store_timestamp_freq)
break;
if (url_i->sip == url->sip && url_i->dip == url->dip && url_i->dport == url->dport &&
url_i->data_len == url->data_len && memcmp(url_i->data, url->data, url_i->data_len) == 0 &&
url_i->flags == url->flags &&
url_i->http_method == url->http_method) {
url_i->hits++;
spin_unlock(&urllogger_store_lock);
urlinfo_release(url);
return;
}
}
urllogger_store_memsize += ALIGN(sizeof(struct urlinfo) + url->data_len, __URLINFO_ALIGN);
urllogger_store_count++;
list_add_tail(&url->list, &urllogger_store_list);
while (urllogger_store_count > urllogger_store_count_limit || urllogger_store_memsize > urllogger_store_memsize_limit) {
pos = urllogger_store_list.next;
url_i = list_entry(pos, struct urlinfo, list);
urllogger_store_memsize -= ALIGN(sizeof(struct urlinfo) + url_i->data_len, __URLINFO_ALIGN);
urllogger_store_count--;
list_del(pos);
urlinfo_release(url_i);
}
spin_unlock(&urllogger_store_lock);
}
static void urllogger_store_clear(void)
{
struct urlinfo *url;
struct list_head *pos, *n;
spin_lock_bh(&urllogger_store_lock);
list_for_each_safe(pos, n, &urllogger_store_list) {
url = list_entry(pos, struct urlinfo, list);
urllogger_store_memsize -= ALIGN(sizeof(struct urlinfo) + url->data_len, __URLINFO_ALIGN);
urllogger_store_count--;
list_del(pos);
urlinfo_release(url);
}
spin_unlock_bh(&urllogger_store_lock);
}
static int hostacl_major = 0;
static int hostacl_minor = 0;
static struct cdev hostacl_cdev;
const char *hostacl_dev_name = "hostacl_ctl";
static struct class *hostacl_class;
static struct device *hostacl_dev;
struct acl_rule {
unsigned char *acl_buffer;
ssize_t acl_buffer_size;
ssize_t acl_buffer_len;
};
#define ACL_RULE_ALLOC_SIZE 256
#define ACL_RULE_MAX 32
static int acl_rule_max = 0;
static struct acl_rule acl_rule_node[ACL_RULE_MAX];
static void acl_rule_init(void)
{
int rule_id;
for (rule_id = 0; rule_id < ACL_RULE_MAX; rule_id++) {
acl_rule_node[rule_id].acl_buffer = NULL;
}
}
static void acl_rule_clear(void)
{
void *tmp;
int rule_id;
for (rule_id = 0; rule_id < ACL_RULE_MAX; rule_id++) {
tmp = acl_rule_node[rule_id].acl_buffer;
if (tmp != NULL) {
acl_rule_node[rule_id].acl_buffer = NULL;
synchronize_rcu();
kfree(tmp);
}
}
acl_rule_max = 0;
}
/* return: 0 = no matched, 1 = matched */
static int urllogger_acl(struct urlinfo *url, int rule_id)
{
int ret = 0;
unsigned char backup_c;
unsigned char *acl_buffer;
acl_buffer = acl_rule_node[rule_id].acl_buffer;
backup_c = url->data[url->host_len];
url->data[url->host_len] = 0;
if (url->host_len >= 1 && acl_buffer != NULL) { /* at least a.b pattern */
int i = 0;
unsigned char b;
unsigned char *ptr = NULL;
while (ptr == NULL) {
ptr = strstr(acl_buffer, url->data + i);
while (ptr != NULL) {
b = *(ptr - 1);
if (((ptr[url->host_len - i] & 0x80) != 0 || ptr[url->host_len - i] == 0) && (b & 0x80) != 0) {
//found
url->acl_idx = (b & 0x1f);
ret = ((b & 0x60) >> 5);
url->acl_action = ret;
ret = 1;
goto __done;
}
if (ptr[url->host_len - i] == 0) {
ptr = NULL;
break;
}
ptr = strstr(ptr + url->host_len - i, url->data + i);
}
while (url->host_len >= i + 1 && url->data[i] != '.') {
i++;
}
if (url->data[i] != '.') {
break;
}
i++;
if (url->host_len < i + 1) {
break;
}
}
}
__done:
url->data[url->host_len] = backup_c;
return ret;
}
static unsigned char *tls_sni_search(unsigned char *data, int *data_len, int *needmore)
{
unsigned char *p = data;
int p_len = *data_len;
int i_data_len = p_len;
unsigned int i = 0;
unsigned short len;
if (p[i + 0] != 0x16) {//Content Type NOT HandShake
return NULL;
}
i += 1 + 2;
if (i >= p_len) return NULL;
len = ntohs(get_byte2(p + i + 0)); //content_len
i += 2;
if (i >= p_len) return NULL;
if (i + len > p_len) {
if (needmore && p[i] == 0x01) //HanShake Type is Client Hello
*needmore = 1;
}
p = p + i;
p_len = len;
i_data_len -= i;
i = 0;
if (p[i + 0] != 0x01) { //HanShake Type NOT Client Hello
return NULL;
}
i += 1;
if (i >= p_len || i >= i_data_len) return NULL;
len = (p[i + 0] << 8) + ntohs(get_byte2(p + i + 0 + 1)); //hanshake_len
i += 1 + 2;
if (i >= p_len || i >= i_data_len) return NULL;
if (i + len > p_len) return NULL;
p = p + i;
p_len = len;
i_data_len -= i;
i = 0;
i += 2 + 32;
if (i >= p_len || i >= i_data_len) return NULL; //tls_v, random
i += 1 + p[i + 0];
if (i >= p_len || i >= i_data_len) return NULL; //session id
i += 2 + ntohs(get_byte2(p + i + 0));
if (i >= p_len || i >= i_data_len) return NULL; //Cipher Suites
i += 1 + p[i + 0];
if (i >= p_len || i >= i_data_len) return NULL; //Compression Methods
len = ntohs(get_byte2(p + i + 0)); //ext_len
i += 2;
if (i + len > p_len) return NULL;
p = p + i;
p_len = len;
i_data_len -= i;
i = 0;
while (i < p_len && i < i_data_len) {
if (get_byte2(p + i + 0) != __constant_htons(0)) {
i += 2 + 2 + ntohs(get_byte2(p + i + 0 + 2));
continue;
}
len = ntohs(get_byte2(p + i + 0 + 2)); //sn_len
i = i + 2 + 2;
if (i + len > p_len || i + len > i_data_len) return NULL;
p = p + i;
p_len = len;
i_data_len -= i;
i = 0;
break;
}
if (i >= p_len || i >= i_data_len) return NULL;
len = ntohs(get_byte2(p + i + 0)); //snl_len
i += 2;
if (i + len > p_len || i + len > i_data_len) return NULL;
p = p + i;
p_len = len;
i_data_len -= i;
i = 0;
while (i < p_len && i < i_data_len) {
if (p[i + 0] != 0) {
i += 1 + 2 + ntohs(get_byte2(p + i + 0 + 1));
continue;
}
len = ntohs(get_byte2(p + i + 0 + 1));
i += 1 + 2;
if (i + len > p_len || i + len > i_data_len) return NULL;
*data_len = len;
return (p + i);
}
return NULL;
}
/* to do it simple:
just assume
1. data begin with 'GET ' or 'POST ' or 'HEAD '
*/
static int http_url_search(unsigned char *data,
int *data_len /*IN: data_len, OUT: host_len */, unsigned char **host,
int *uri_len, unsigned char **uri, int *http_method)
{
unsigned char *p = data;
int p_len = *data_len;
unsigned int i = 0;
if (i + 5 > p_len) return -1;
if ((p[i] == 'G' || p[i] == 'g') &&
(p[i + 1] == 'E' || p[i + 1] == 'e') &&
(p[i + 2] == 'T' || p[i + 2] == 't') &&
(p[i + 3] == ' ' || p[i + 3] == ' ')) {
i += 4;
*http_method = NATFLOW_HTTP_GET;
} else if ((p[i] == 'P' || p[i] == 'p') &&
(p[i + 1] == 'O' || p[i + 1] == 'o') &&
(p[i + 2] == 'S' || p[i + 2] == 's') &&
(p[i + 3] == 'T' || p[i + 3] == 't') &&
(p[i + 4] == ' ' || p[i + 4] == ' ')) {
i += 5;
*http_method = NATFLOW_HTTP_POST;
} else if ((p[i] == 'H' || p[i] == 'h') &&
(p[i + 1] == 'E' || p[i + 1] == 'e') &&
(p[i + 2] == 'A' || p[i + 2] == 'a') &&
(p[i + 3] == 'D' || p[i + 3] == 'd') &&
(p[i + 4] == ' ' || p[i + 4] == ' ')) {
i += 5;
*http_method = NATFLOW_HTTP_HEAD;
} else {
return 0;
}
while (i < p_len && p[i] == ' ') i++;
if (i >= p_len) return -1;
if (p[i] != '/') return -1;
*uri = p + i;
i++;
while (i < p_len && p[i] != ' ') i++;
if (i >= p_len) return -1;
if (p[i] != ' ') return -1;
*uri_len = p + i - *uri;
i++;
while (i < p_len && p[i] != '\n') i++;
if (i >= p_len) return -1;
i++;
do {
if (i + 5 > p_len) return -1;
if ((p[i] == 'H' || p[i] == 'h') &&
(p[i + 1] == 'o' || p[i + 1] == 'O') &&
(p[i + 2] == 's' || p[i + 2] == 'S') &&
(p[i + 3] == 't' || p[i + 3] == 'T') &&
p[i + 4] == ':') {
i += 5;
while (i < p_len && p[i] == ' ') i++;
if (i >= p_len) return -1;
*host = p + i;
i++;
while (i < p_len && p[i] != ' ' && p[i] != '\r' && p[i] != '\n') i++;
if (i >= p_len) return -1;
if (p[i] != ' ' && p[i] != '\r' && p[i] != '\n') return -1;
*data_len = p + i - *host;
return *data_len + *uri_len;
}
while (i < p_len && p[i] != '\n') i++;
i++;
} while (1);
return 0; /* not found */
}
static inline void natflow_urllogger_tcp_reply_rstack(const struct net_device *dev, struct sk_buff *oskb, struct nf_conn *ct, int pppoe_hdr)
{
struct sk_buff *nskb;
struct ethhdr *neth, *oeth;
struct iphdr *niph, *oiph;
struct tcphdr *otcph, *ntcph;
int len;
unsigned int csum;
int offset, header_len;
int pppoe_len = 0;
if (pppoe_hdr) {
pppoe_len = PPPOE_SES_HLEN;
skb_push(oskb, PPPOE_SES_HLEN);
oskb->protocol = __constant_htons(ETH_P_PPP_SES);
}
oeth = (struct ethhdr *)skb_mac_header(oskb);
oiph = ip_hdr(oskb);
otcph = (struct tcphdr *)((void *)oiph + oiph->ihl*4);
offset = pppoe_len + sizeof(struct iphdr) + sizeof(struct tcphdr) - oskb->len;
header_len = offset < 0 ? 0 : offset;
nskb = skb_copy_expand(oskb, skb_headroom(oskb), header_len, GFP_ATOMIC);
if (!nskb) {
NATFLOW_ERROR("alloc_skb fail\n");
goto out;
}
if (offset <= 0) {
if (pskb_trim(nskb, nskb->len + offset)) {
NATFLOW_ERROR("pskb_trim fail: len=%d, offset=%d\n", nskb->len, offset);
consume_skb(nskb);
goto out;
}
} else {
nskb->len += offset;
nskb->tail += offset;
}
//setup mac header
neth = eth_hdr(nskb);
niph = ip_hdr(nskb);
if ((char *)niph - (char *)neth >= ETH_HLEN) {
memcpy(neth->h_dest, oeth->h_source, ETH_ALEN);
memcpy(neth->h_source, oeth->h_dest, ETH_ALEN);
//neth->h_proto = htons(ETH_P_IP);
}
//setup ip header
memset(niph, 0, sizeof(struct iphdr));
niph->saddr = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.u3.ip;
niph->daddr = oiph->saddr;
niph->version = oiph->version;
niph->ihl = 5;
niph->tos = 0;
niph->tot_len = htons(nskb->len - pppoe_len);
niph->ttl = 0x80;
niph->protocol = oiph->protocol;
niph->id = __constant_htons(0xDEAD);
niph->frag_off = 0x0;
ip_send_check(niph);
//setup tcp header
ntcph = (struct tcphdr *)((char *)ip_hdr(nskb) + sizeof(struct iphdr));
memset(ntcph, 0, sizeof(struct tcphdr));
ntcph->source = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.u.all;
ntcph->dest = otcph->source;
ntcph->seq = otcph->ack_seq;
ntcph->ack_seq = htonl(ntohl(otcph->seq) + ntohs(oiph->tot_len) - (oiph->ihl<<2) - (otcph->doff<<2));
ntcph->doff = 5;
ntcph->ack = 1;
ntcph->rst = 1;
ntcph->psh = 0;
ntcph->fin = 0;
ntcph->window = 0;
//sum check
len = ntohs(niph->tot_len) - (niph->ihl<<2);
csum = csum_partial((char*)ntcph, len, 0);
ntcph->check = tcp_v4_check(len, niph->saddr, niph->daddr, csum);
//ready to send out
skb_push(nskb, (char *)niph - (char *)neth - pppoe_len);
if (pppoe_hdr) {
struct pppoe_hdr *ph = (struct pppoe_hdr *)((void *)eth_hdr(nskb) + ETH_HLEN);
ph->length = htons(ntohs(ip_hdr(nskb)->tot_len) + 2);
}
nskb->dev = (struct net_device *)dev;
nskb->ip_summed = CHECKSUM_UNNECESSARY;
dev_queue_xmit(nskb);
out:
if (pppoe_hdr) {
oskb->protocol = __constant_htons(ETH_P_IP);
skb_pull(oskb, PPPOE_SES_HLEN);
}
}
static inline void natflow_urllogger_tcp_reply_rstack6(const struct net_device *dev, struct sk_buff *oskb, struct nf_conn *ct, int pppoe_hdr)
{
struct sk_buff *nskb;
struct ethhdr *neth, *oeth;
struct ipv6hdr *niph, *oiph;
struct tcphdr *otcph, *ntcph;
int len;
unsigned int csum;
int offset, header_len;
int pppoe_len = 0;
if (pppoe_hdr) {
pppoe_len = PPPOE_SES_HLEN;
skb_push(oskb, PPPOE_SES_HLEN);
oskb->protocol = __constant_htons(ETH_P_PPP_SES);
}
oeth = (struct ethhdr *)skb_mac_header(oskb);
oiph = ipv6_hdr(oskb);
otcph = (struct tcphdr *)((void *)oiph + sizeof(struct ipv6hdr));
offset = pppoe_len + sizeof(struct ipv6hdr) + sizeof(struct tcphdr) - oskb->len;
header_len = offset < 0 ? 0 : offset;
nskb = skb_copy_expand(oskb, skb_headroom(oskb), header_len, GFP_ATOMIC);
if (!nskb) {
NATFLOW_ERROR("alloc_skb fail\n");
goto out;
}
if (offset <= 0) {
if (pskb_trim(nskb, nskb->len + offset)) {
NATFLOW_ERROR("pskb_trim fail: len=%d, offset=%d\n", nskb->len, offset);
consume_skb(nskb);
goto out;
}
} else {
nskb->len += offset;
nskb->tail += offset;
}
//setup mac header
neth = eth_hdr(nskb);
niph = ipv6_hdr(nskb);
if ((char *)niph - (char *)neth >= ETH_HLEN) {
memcpy(neth->h_dest, oeth->h_source, ETH_ALEN);
memcpy(neth->h_source, oeth->h_dest, ETH_ALEN);
//neth->h_proto = htons(ETH_P_IP);
}
//setup ip header
memset(niph, 0, sizeof(struct iphdr));
niph->version = oiph->version;
niph->priority = oiph->priority;
niph->saddr = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.u3.in6;
niph->daddr = oiph->saddr;
niph->flow_lbl[2] = niph->flow_lbl[1] = niph->flow_lbl[0] = 0;
niph->payload_len = htons(sizeof(struct tcphdr));
niph->nexthdr = IPPROTO_TCP;
niph->hop_limit = 255;
//setup tcp header
ntcph = (struct tcphdr *)((char *)ip_hdr(nskb) + sizeof(struct ipv6hdr));
memset(ntcph, 0, sizeof(struct tcphdr));
ntcph->source = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.u.all;
ntcph->dest = otcph->source;
ntcph->seq = otcph->ack_seq;
ntcph->ack_seq = htonl(ntohl(otcph->seq) + ntohs(oiph->payload_len) - (otcph->doff<<2));
ntcph->doff = 5;
ntcph->ack = 1;
ntcph->rst = 1;
ntcph->psh = 0;
ntcph->fin = 0;
ntcph->window = 0;
//sum check
len = ntohs(niph->payload_len);
csum = csum_partial((char*)ntcph, len, 0);
ntcph->check = tcp_v6_check(len, &niph->saddr, &niph->daddr, csum);
//ready to send out
skb_push(nskb, (char *)niph - (char *)neth - pppoe_len);
if (pppoe_hdr) {
struct pppoe_hdr *ph = (struct pppoe_hdr *)((void *)eth_hdr(nskb) + ETH_HLEN);
ph->length = htons(ntohs(ipv6_hdr(nskb)->payload_len) + sizeof(struct ipv6hdr) + 2);
}
nskb->dev = (struct net_device *)dev;
nskb->ip_summed = CHECKSUM_UNNECESSARY;
dev_queue_xmit(nskb);
out:
if (pppoe_hdr) {
oskb->protocol = __constant_htons(ETH_P_IP);
skb_pull(oskb, PPPOE_SES_HLEN);
}
}
struct urllogger_sni_cache_node {
unsigned long active_jiffies;
union {
__be32 src_ip;
struct in6_addr src_ipv6;
};
union {
__be32 dst_ip;
struct in6_addr dst_ipv6;
};
__be16 src_port;
__be16 dst_port;
unsigned short add_data_len;
struct sk_buff *skb;
};
#define URLLOGGER_CACHE_TIMEOUT 4
#define MAX_URLLOGGER_SNI_CACHE_NODE 64
static struct urllogger_sni_cache_node urllogger_sni_cache[NR_CPUS][MAX_URLLOGGER_SNI_CACHE_NODE];
static inline void urllogger_sni_cache_init(void)
{
int i, j;
for (i = 0; i < NR_CPUS; i++) {
for (j = 0; j < MAX_URLLOGGER_SNI_CACHE_NODE; j++) {
urllogger_sni_cache[i][j].skb = NULL;
}
}
}
static inline void urllogger_sni_cache_cleanup(void)
{
int i, j;
for (i = 0; i < NR_CPUS; i++) {
for (j = 0; j < MAX_URLLOGGER_SNI_CACHE_NODE; j++) {
if (urllogger_sni_cache[i][j].skb != NULL) {
consume_skb(urllogger_sni_cache[i][j].skb);
urllogger_sni_cache[i][j].skb = NULL;
}
}
}
}
static inline int urllogger_sni_cache_attach(__be32 src_ip, __be16 src_port, __be32 dst_ip, __be16 dst_port, struct sk_buff *skb, unsigned short add_data_len)
{
int i = smp_processor_id();
int j;
int next_to_use = MAX_URLLOGGER_SNI_CACHE_NODE;
for (j = 0; j < MAX_URLLOGGER_SNI_CACHE_NODE; j++) {
if (urllogger_sni_cache[i][j].skb != NULL &&
urllogger_sni_cache[i][j].src_ip == src_ip &&
urllogger_sni_cache[i][j].src_port == src_port &&
urllogger_sni_cache[i][j].dst_ip == dst_ip &&
urllogger_sni_cache[i][j].dst_port == dst_port) {
return -EEXIST;
} else if (next_to_use == MAX_URLLOGGER_SNI_CACHE_NODE && urllogger_sni_cache[i][j].skb == NULL) {
next_to_use = j;
}
}
if (next_to_use == MAX_URLLOGGER_SNI_CACHE_NODE) {
return -ENOMEM;
}
urllogger_sni_cache[i][next_to_use].src_ip = src_ip;
urllogger_sni_cache[i][next_to_use].src_port = src_port;
urllogger_sni_cache[i][next_to_use].dst_ip = dst_ip;
urllogger_sni_cache[i][next_to_use].dst_port = dst_port;
urllogger_sni_cache[i][next_to_use].add_data_len = add_data_len;
urllogger_sni_cache[i][next_to_use].skb = skb;
urllogger_sni_cache[i][next_to_use].active_jiffies = (unsigned long)jiffies;
return 0;
}
static inline int urllogger_sni_cache_attach6(struct in6_addr *src_ip, __be16 src_port, struct in6_addr *dst_ip, __be16 dst_port, struct sk_buff *skb, unsigned short add_data_len)
{
int i = smp_processor_id();
int j;
int next_to_use = MAX_URLLOGGER_SNI_CACHE_NODE;
for (j = 0; j < MAX_URLLOGGER_SNI_CACHE_NODE; j++) {
if (urllogger_sni_cache[i][j].skb != NULL &&
memcmp(&urllogger_sni_cache[i][j].src_ipv6, src_ip, 16) == 0 &&
urllogger_sni_cache[i][j].src_port == src_port &&
memcmp(&urllogger_sni_cache[i][j].dst_ipv6, dst_ip, 16) == 0 &&
urllogger_sni_cache[i][j].dst_port == dst_port) {
return -EEXIST;
} else if (next_to_use == MAX_URLLOGGER_SNI_CACHE_NODE && urllogger_sni_cache[i][j].skb == NULL) {
next_to_use = j;
}
}
if (next_to_use == MAX_URLLOGGER_SNI_CACHE_NODE) {
return -ENOMEM;
}
memcpy(&urllogger_sni_cache[i][next_to_use].src_ipv6, src_ip, 16);
urllogger_sni_cache[i][next_to_use].src_port = src_port;
memcpy(&urllogger_sni_cache[i][next_to_use].dst_ipv6, dst_ip, 16);
urllogger_sni_cache[i][next_to_use].dst_port = dst_port;
urllogger_sni_cache[i][next_to_use].add_data_len = add_data_len;
urllogger_sni_cache[i][next_to_use].skb = skb;
urllogger_sni_cache[i][next_to_use].active_jiffies = (unsigned long)jiffies;
return 0;
}
static inline struct sk_buff *urllogger_sni_cache_detach(__be32 src_ip, __be16 src_port, __be32 dst_ip, __be16 dst_port, unsigned short *add_data_len)
{
int i = smp_processor_id();
int j = 0;
struct sk_buff *skb = NULL;
for (j = 0; j < MAX_URLLOGGER_SNI_CACHE_NODE; j++) {
if (urllogger_sni_cache[i][j].skb != NULL) {
if (time_after(jiffies, urllogger_sni_cache[i][j].active_jiffies + URLLOGGER_CACHE_TIMEOUT * HZ)) {
consume_skb(urllogger_sni_cache[i][j].skb);
urllogger_sni_cache[i][j].skb = NULL;
} else if (urllogger_sni_cache[i][j].src_ip == src_ip &&
urllogger_sni_cache[i][j].src_port == src_port &&
urllogger_sni_cache[i][j].dst_ip == dst_ip &&
urllogger_sni_cache[i][j].dst_port == dst_port) {
skb = urllogger_sni_cache[i][j].skb;
*add_data_len = urllogger_sni_cache[i][j].add_data_len;
urllogger_sni_cache[i][j].skb = NULL;
break;
}
}
}
for (; j < MAX_URLLOGGER_SNI_CACHE_NODE; j++) {
if (urllogger_sni_cache[i][j].skb != NULL) {
if (time_after(jiffies, urllogger_sni_cache[i][j].active_jiffies + URLLOGGER_CACHE_TIMEOUT * HZ)) {
consume_skb(urllogger_sni_cache[i][j].skb);
urllogger_sni_cache[i][j].skb = NULL;
}
}
}
return skb;
}
static inline struct sk_buff *urllogger_sni_cache_detach6(struct in6_addr *src_ip, __be16 src_port, struct in6_addr *dst_ip, __be16 dst_port, unsigned short *add_data_len)
{
int i = smp_processor_id();
int j = 0;
struct sk_buff *skb = NULL;
for (j = 0; j < MAX_URLLOGGER_SNI_CACHE_NODE; j++) {
if (urllogger_sni_cache[i][j].skb != NULL) {
if (time_after(jiffies, urllogger_sni_cache[i][j].active_jiffies + URLLOGGER_CACHE_TIMEOUT * HZ)) {
consume_skb(urllogger_sni_cache[i][j].skb);
urllogger_sni_cache[i][j].skb = NULL;
} else if (memcmp(&urllogger_sni_cache[i][j].src_ipv6, src_ip, 16) == 0 &&
urllogger_sni_cache[i][j].src_port == src_port &&
memcmp(&urllogger_sni_cache[i][j].dst_ipv6, dst_ip, 16) == 0 &&
urllogger_sni_cache[i][j].dst_port == dst_port) {
skb = urllogger_sni_cache[i][j].skb;
*add_data_len = urllogger_sni_cache[i][j].add_data_len;
urllogger_sni_cache[i][j].skb = NULL;
break;
}
}
}
for (; j < MAX_URLLOGGER_SNI_CACHE_NODE; j++) {
if (urllogger_sni_cache[i][j].skb != NULL) {
if (time_after(jiffies, urllogger_sni_cache[i][j].active_jiffies + URLLOGGER_CACHE_TIMEOUT * HZ)) {
consume_skb(urllogger_sni_cache[i][j].skb);
urllogger_sni_cache[i][j].skb = NULL;
}
}
}
return skb;
}
#if LINUX_VERSION_CODE < KERNEL_VERSION(3, 13, 0)
static unsigned int natflow_urllogger_hook_v1(unsigned int hooknum,
struct sk_buff *skb,
const struct net_device *in,
const struct net_device *out,
int (*okfn)(struct sk_buff *))
{
#elif LINUX_VERSION_CODE < KERNEL_VERSION(4, 1, 0)
static unsigned int natflow_urllogger_hook_v1(const struct nf_hook_ops *ops,
struct sk_buff *skb,
const struct net_device *in,
const struct net_device *out,
int (*okfn)(struct sk_buff *))
{
unsigned int hooknum = ops->hooknum;
#elif LINUX_VERSION_CODE < KERNEL_VERSION(4, 4, 0)
static unsigned int natflow_urllogger_hook_v1(const struct nf_hook_ops *ops,
struct sk_buff *skb,
const struct nf_hook_state *state)
{
unsigned int hooknum = state->hook;
const struct net_device *in = state->in;
const struct net_device *out = state->out;
#else
static unsigned int natflow_urllogger_hook_v1(void *priv,
struct sk_buff *skb,
const struct nf_hook_state *state)
{
unsigned int hooknum = state->hook;
const struct net_device *in = state->in;
#if LINUX_VERSION_CODE < KERNEL_VERSION(4, 10, 0)
const struct net_device *out = state->out;
#endif
#endif
int ret = NF_ACCEPT;
enum ip_conntrack_info ctinfo;
int data_len;
unsigned char *data;
natflow_t *nf;
struct nf_conn *ct;
struct iphdr *iph;
void *l4;
int bridge = 0;
if (!urllogger_store_enable)
return NF_ACCEPT;
if (skb->protocol == __constant_htons(ETH_P_PPP_SES) &&
pppoe_proto(skb) == __constant_htons(PPP_IP) /* Internet Protocol */) {
skb_pull(skb, PPPOE_SES_HLEN);
skb->protocol = __constant_htons(ETH_P_IP);
skb->network_header += PPPOE_SES_HLEN;
bridge = 1;
} else if (skb->protocol == __constant_htons(ETH_P_PPP_SES) &&
pppoe_proto(skb) == __constant_htons(PPP_IPV6) /* Internet Protocol version 6 */) {
skb_pull(skb, PPPOE_SES_HLEN);
skb->protocol = __constant_htons(ETH_P_IPV6);
skb->network_header += PPPOE_SES_HLEN;
bridge = 1;
} else if (skb->protocol != __constant_htons(ETH_P_IP) && skb->protocol != __constant_htons(ETH_P_IPV6)) {
return NF_ACCEPT;
}
ct = nf_ct_get(skb, &ctinfo);
if (NULL == ct)
goto out;
if (CTINFO2DIR(ctinfo) != IP_CT_DIR_ORIGINAL)
goto out;
if ((ct->status & IPS_NATFLOW_URLLOGGER_HANDLED))
goto out;
if (ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.src.l3num == AF_INET6)
goto urllogger_hook_ipv6_main;
iph = ip_hdr(skb);
if (iph->protocol != IPPROTO_TCP) {
goto out;
}
if (skb_try_make_writable(skb, iph->ihl * 4 + sizeof(struct tcphdr))) {
goto out;
}
iph = ip_hdr(skb);
l4 = (void *)iph + iph->ihl * 4;
/* pause fastnat path */
nf = natflow_session_get(ct);
if (nf && !(nf->status & NF_FF_URLLOGGER_USE)) {
/* tell FF -urllogger- need this conn */
simple_set_bit(NF_FF_URLLOGGER_USE_BIT, &nf->status);
}
data_len = ntohs(iph->tot_len) - (iph->ihl * 4 + TCPH(l4)->doff * 4);
if (data_len > 0) {
struct sk_buff *prev_skb = NULL;
unsigned char *host = NULL;
int host_len;
unsigned short add_data_len = 0;
if (skb_try_make_writable(skb, skb->len)) {
goto out;
}
iph = ip_hdr(skb);
l4 = (void *)iph + iph->ihl * 4;
prev_skb = urllogger_sni_cache_detach(iph->saddr, TCPH(l4)->source, iph->daddr, TCPH(l4)->dest, &add_data_len);
if (prev_skb) {
struct iphdr *prev_iph = ip_hdr(prev_skb);
void *prev_l4 = (void *)prev_iph + prev_iph->ihl * 4;
int prev_data_len = ntohs(prev_iph->tot_len) - (prev_iph->ihl * 4 + TCPH(prev_l4)->doff * 4);
data = skb->data + iph->ihl * 4 + TCPH(l4)->doff * 4;
if (ntohl(TCPH(l4)->seq) == ntohl(TCPH(prev_l4)->seq) + prev_data_len + add_data_len) {
int needmore = 0;
if (skb_tailroom(prev_skb) < add_data_len + data_len &&
pskb_expand_head(prev_skb, 0, add_data_len + data_len, GFP_ATOMIC)) {
NATFLOW_ERROR("(NUHv1)" DEBUG_TCP_FMT ": pskb_expand_head failed\n", DEBUG_TCP_ARG(iph,l4));
consume_skb(prev_skb);
return NF_ACCEPT;
}
prev_iph = ip_hdr(prev_skb);
prev_l4 = (void *)prev_iph + prev_iph->ihl * 4;
memcpy(prev_skb->data + prev_skb->len + add_data_len, data, data_len);
add_data_len += data_len;
data = prev_skb->data + prev_iph->ihl * 4 + TCPH(prev_l4)->doff * 4;
host_len = prev_data_len + add_data_len;
host = tls_sni_search(data, &host_len, &needmore);
if (!host && needmore == 1) {
if (add_data_len >= 32 * 1024 ||
urllogger_sni_cache_attach(prev_iph->saddr, TCPH(prev_l4)->source,
prev_iph->daddr, TCPH(prev_l4)->dest, prev_skb, add_data_len) != 0) {
NATFLOW_ERROR("(NUHv1)" DEBUG_TCP_FMT ": urllogger_sni_cache_attach failed with add_data_len=%u\n", DEBUG_TCP_ARG(iph,l4), add_data_len);
consume_skb(prev_skb);
goto __urllogger_ip_skip;
}
return NF_ACCEPT;
}
} else if (ntohl(TCPH(l4)->seq) == ntohl(TCPH(prev_l4)->seq)) {
if (urllogger_sni_cache_attach(prev_iph->saddr, TCPH(prev_l4)->source,
prev_iph->daddr, TCPH(prev_l4)->dest, prev_skb, add_data_len) != 0) {
NATFLOW_ERROR("(NUHv1)" DEBUG_TCP_FMT ": urllogger_sni_cache_attach failed\n", DEBUG_TCP_ARG(iph,l4));
consume_skb(prev_skb);
goto __urllogger_ip_skip;
}
return NF_ACCEPT;
} else {
consume_skb(prev_skb);
goto __urllogger_ip_skip;
}
} else {
int needmore = 0;
data = skb->data + iph->ihl * 4 + TCPH(l4)->doff * 4;
host_len = data_len;
host = tls_sni_search(data, &host_len, &needmore);
if (!host && needmore == 1) {
prev_skb = skb_copy(skb, GFP_ATOMIC);
if (prev_skb) {
if (urllogger_sni_cache_attach(iph->saddr, TCPH(l4)->source, iph->daddr, TCPH(l4)->dest, prev_skb, 0) != 0) {
NATFLOW_ERROR("(NUHv1)" DEBUG_TCP_FMT ": urllogger_sni_cache_attach failed\n", DEBUG_TCP_ARG(iph,l4));
consume_skb(prev_skb);
goto __urllogger_ip_skip;
}
}
return NF_ACCEPT;
}
}
data = skb->data + iph->ihl * 4 + TCPH(l4)->doff * 4;
__urllogger_ip_skip:
/* check one packet only */
set_bit(IPS_NATFLOW_URLLOGGER_HANDLED_BIT, &ct->status);
if (nf && (nf->status & NF_FF_URLLOGGER_USE)) {
/* tell FF -urllogger- has finished it's job */
simple_clear_bit(NF_FF_URLLOGGER_USE_BIT, &nf->status);
}
if (host) {
int rule_id = 0;
struct urlinfo *url = kmalloc(ALIGN(sizeof(struct urlinfo) + host_len + 1, __URLINFO_ALIGN), GFP_ATOMIC);
if (!url) {
if (prev_skb) consume_skb(prev_skb);
goto out;
}
INIT_LIST_HEAD(&url->list);
url->host_len = urlinfo_copy_host_tolower(url->data, host, host_len);
if (prev_skb) consume_skb(prev_skb);
url->data[host_len] = 0;