zapret/nfq/nfqws.c

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C
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2021-03-04 11:30:38 +00:00
#define _GNU_SOURCE
#include "nfqws.h"
#include "sec.h"
#include "desync.h"
#include "helpers.h"
#include "checksum.h"
#include "params.h"
#include "protocol.h"
#include "hostlist.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <stdbool.h>
#include <stdint.h>
#include <arpa/inet.h>
#include <getopt.h>
#include <fcntl.h>
#include <pwd.h>
#include <signal.h>
#include <errno.h>
#include <time.h>
#include <sys/param.h>
#include <sys/socket.h>
#include <netinet/in.h>
#ifdef __linux__
#include <libnetfilter_queue/libnetfilter_queue.h>
#define NF_DROP 0
#define NF_ACCEPT 1
#endif
#ifndef IPPROTO_DIVERT
#define IPPROTO_DIVERT 258
#endif
struct params_s params;
static bool bHup = false;
static void onhup(int sig)
{
printf("HUP received !\n");
if (params.hostlist)
printf("Will reload hostlist on next request\n");
bHup = true;
}
// should be called in normal execution
static void dohup()
{
if (bHup)
{
if (params.hostlist)
{
if (!LoadHostList(&params.hostlist, params.hostfile))
{
// what will we do without hostlist ?? sure, gonna die
exit(1);
}
}
bHup = false;
}
}
#ifdef __linux__
static packet_process_result processPacketData(uint8_t *data_pkt, size_t len_pkt, uint32_t *mark)
#else
static packet_process_result processPacketData(uint8_t *data_pkt, size_t len_pkt)
#endif
{
struct ip *ip = NULL;
struct ip6_hdr *ip6hdr = NULL;
struct tcphdr *tcphdr = NULL;
size_t len = len_pkt, len_tcp;
uint8_t *data = data_pkt;
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packet_process_result res = pass;
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uint8_t proto;
#ifdef __linux__
if (*mark & params.desync_fwmark)
{
DLOG("ignoring generated packet\n")
return res;
}
#endif
if (proto_check_ipv4(data, len))
{
ip = (struct ip *) data;
proto = ip->ip_p;
proto_skip_ipv4(&data, &len);
if (params.debug)
{
printf("IP4: ");
print_ip(ip);
}
}
else if (proto_check_ipv6(data, len))
{
ip6hdr = (struct ip6_hdr *) data;
proto_skip_ipv6(&data, &len, &proto);
if (params.debug)
{
printf("IP6: ");
print_ip6hdr(ip6hdr, proto);
}
}
else
{
// not ipv6 and not ipv4
return res;
}
if (proto==IPPROTO_TCP && proto_check_tcp(data, len))
{
tcphdr = (struct tcphdr *) data;
len_tcp = len;
proto_skip_tcp(&data, &len);
if (params.debug)
{
printf(" ");
print_tcphdr(tcphdr);
printf("\n");
}
if (len) { DLOG("TCP: ") hexdump_limited_dlog(data, len, 32); DLOG("\n") }
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res = dpi_desync_packet(data_pkt, len_pkt, ip, ip6hdr, tcphdr, len_tcp, data, len);
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// in my FreeBSD divert tests only ipv4 packets were reinjected with correct checksum
// ipv6 packets were with incorrect checksum
#ifdef __FreeBSD__
// FreeBSD tend to pass ipv6 frames with wrong checksum
if (res==modify || ip6hdr)
#else
if (res==modify)
#endif
tcp_fix_checksum(tcphdr,len_tcp,ip,ip6hdr);
}
else
{
if (params.debug) printf("\n");
}
return res;
}
#ifdef __linux__
static int nfq_cb(struct nfq_q_handle *qh, struct nfgenmsg *nfmsg,
struct nfq_data *nfa, void *cookie)
{
int id;
size_t len;
struct nfqnl_msg_packet_hdr *ph;
uint8_t *data;
ph = nfq_get_msg_packet_hdr(nfa);
id = ph ? ntohl(ph->packet_id) : 0;
uint32_t mark = nfq_get_nfmark(nfa);
len = nfq_get_payload(nfa, &data);
DLOG("packet: id=%d len=%zu\n", id, len)
if (len >= 0)
{
switch (processPacketData(data, len, &mark))
{
case modify:
DLOG("packet: id=%d pass modified\n", id);
return nfq_set_verdict2(qh, id, NF_ACCEPT, mark, len, data);
case drop:
DLOG("packet: id=%d drop\n", id);
return nfq_set_verdict2(qh, id, NF_DROP, mark, 0, NULL);
}
}
DLOG("packet: id=%d pass unmodified\n", id);
return nfq_set_verdict2(qh, id, NF_ACCEPT, mark, 0, NULL);
}
static int nfq_main()
{
struct nfq_handle *h = NULL;
struct nfq_q_handle *qh = NULL;
int fd,rv;
uint8_t buf[16384] __attribute__((aligned));
printf("opening library handle\n");
h = nfq_open();
if (!h) {
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perror("nfq_open()");
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goto exiterr;
}
printf("unbinding existing nf_queue handler for AF_INET (if any)\n");
if (nfq_unbind_pf(h, AF_INET) < 0) {
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perror("nfq_unbind_pf()");
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goto exiterr;
}
printf("binding nfnetlink_queue as nf_queue handler for AF_INET\n");
if (nfq_bind_pf(h, AF_INET) < 0) {
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perror("nfq_bind_pf()");
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goto exiterr;
}
printf("binding this socket to queue '%u'\n", params.qnum);
qh = nfq_create_queue(h, params.qnum, &nfq_cb, &params);
if (!qh) {
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perror("nfq_create_queue()");
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goto exiterr;
}
printf("setting copy_packet mode\n");
if (nfq_set_mode(qh, NFQNL_COPY_PACKET, 0xffff) < 0) {
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perror("can't set packet_copy mode");
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goto exiterr;
}
if (nfq_set_queue_maxlen(qh, Q_MAXLEN) < 0) {
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perror("can't set queue maxlen");
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goto exiterr;
}
// accept packets if they cant be handled
if (nfq_set_queue_flags(qh, NFQA_CFG_F_FAIL_OPEN , NFQA_CFG_F_FAIL_OPEN))
{
fprintf(stderr, "can't set queue flags. its OK on linux <3.6\n");
// dot not fail. not supported on old linuxes <3.6
}
if (params.droproot && !droproot(params.uid, params.gid))
goto exiterr;
print_id();
signal(SIGHUP, onhup);
desync_init();
fd = nfq_fd(h);
// increase socket buffer size. on slow systems reloading hostlist can take a while.
// if too many unhandled packets are received its possible to get "no buffer space available" error
if (!set_socket_buffers(fd,Q_RCVBUF/2,Q_SNDBUF/2))
goto exiterr;
do
{
while ((rv = recv(fd, buf, sizeof(buf), 0)) && rv >= 0)
{
dohup();
int r = nfq_handle_packet(h, buf, rv);
if (r) fprintf(stderr, "nfq_handle_packet error %d\n", r);
}
fprintf(stderr, "recv: errno %d\n",errno);
perror("recv");
// do not fail on ENOBUFS
} while(errno==ENOBUFS);
printf("unbinding from queue 0\n");
nfq_destroy_queue(qh);
#ifdef INSANE
/* normally, applications SHOULD NOT issue this command, since
* it detaches other programs/sockets from AF_INET, too ! */
printf("unbinding from AF_INET\n");
nfq_unbind_pf(h, AF_INET);
#endif
printf("closing library handle\n");
nfq_close(h);
return 0;
exiterr:
if (qh) nfq_destroy_queue(qh);
if (h) nfq_close(h);
return 1;
}
#elif defined(BSD)
static int dvt_main()
{
uint8_t buf[16384] __attribute__((aligned));
struct sockaddr_storage sa_from;
int fd[2] = {-1,-1}; // 4,6
int i,r,res=1,fdct=1,fdmax;
unsigned int id=0;
socklen_t socklen;
ssize_t rd,wr;
packet_process_result ppr;
fd_set fdset;
{
struct sockaddr_in bp4;
bp4.sin_family = AF_INET;
bp4.sin_port = htons(params.port);
bp4.sin_addr.s_addr = INADDR_ANY;
printf("creating divert4 socket\n");
fd[0] = socket(AF_INET, SOCK_RAW, IPPROTO_DIVERT);
if (fd[0] == -1) {
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perror("socket (DIVERT4)");
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goto exiterr;
}
printf("binding divert4 socket\n");
if (bind(fd[0], (struct sockaddr*)&bp4, sizeof(bp4)) < 0)
{
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perror("bind (DIVERT4)");
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goto exiterr;
}
if (!set_socket_buffers(fd[0],Q_RCVBUF,Q_SNDBUF))
goto exiterr;
}
#ifdef __OpenBSD__
{
// in OpenBSD must use separate divert sockets for ipv4 and ipv6
struct sockaddr_in6 bp6;
memset(&bp6,0,sizeof(bp6));
bp6.sin6_family = AF_INET6;
bp6.sin6_port = htons(params.port);
printf("creating divert6 socket\n");
fd[1] = socket(AF_INET6, SOCK_RAW, IPPROTO_DIVERT);
if (fd[1] == -1) {
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perror("socket (DIVERT6)");
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goto exiterr;
}
printf("binding divert6 socket\n");
if (bind(fd[1], (struct sockaddr*)&bp6, sizeof(bp6)) < 0)
{
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perror("bind (DIVERT6)");
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goto exiterr;
}
fdct++;
if (!set_socket_buffers(fd[1],Q_RCVBUF,Q_SNDBUF))
goto exiterr;
}
#endif
fdmax = (fd[0]>fd[1] ? fd[0] : fd[1]) + 1;
printf("initializing raw sockets with sockarg 0x%08X (%u)\n", params.desync_fwmark, params.desync_fwmark);
if (!rawsend_preinit(params.desync_fwmark))
goto exiterr;
if (params.droproot && !droproot(params.uid, params.gid))
goto exiterr;
print_id();
signal(SIGHUP, onhup);
desync_init();
for(;;)
{
FD_ZERO(&fdset);
for(i=0;i<fdct;i++) FD_SET(fd[i], &fdset);
r = select(fdmax,&fdset,NULL,NULL,NULL);
if (r==-1)
{
if (errno==EINTR)
{
// a signal received
dohup();
continue;
}
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perror("select");
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goto exiterr;
}
for(i=0;i<fdct;i++)
{
if (FD_ISSET(fd[i], &fdset))
{
socklen = sizeof(sa_from);
rd = recvfrom(fd[i], buf, sizeof(buf), 0, (struct sockaddr*)&sa_from, &socklen);
if (rd<0)
{
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perror("recvfrom");
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goto exiterr;
}
else if (rd>0)
{
DLOG("packet: id=%u len=%zd\n", id, rd)
ppr = processPacketData(buf, rd);
switch (ppr)
{
case pass:
case modify:
DLOG(ppr==pass ? "packet: id=%u reinject unmodified\n" : "packet: id=%u reinject modified\n", id);
wr = sendto(fd[i], buf, rd, 0, (struct sockaddr*)&sa_from, socklen);
if (wr<0)
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perror("reinject sendto");
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else if (wr!=rd)
fprintf(stderr,"reinject sendto: not all data was reinjected. received %zd, sent %zd\n", rd, wr);
break;
default:
DLOG("packet: id=%u drop\n", id);
}
id++;
}
else
{
DLOG("unexpected zero size recvfrom\n")
}
}
}
}
res=0;
exiterr:
if (fd[0]!=-1) close(fd[0]);
if (fd[1]!=-1) close(fd[1]);
return res;
}
#endif
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static bool parse_scale_factor(char *s, uint16_t *wsize, uint8_t *wscale)
{
int v;
char *p;
if ((p = strchr(s,':'))) *p++=0;
v = atoi(s);
if (v < 0 || v>65535)
{
fprintf(stderr, "bad wsize\n");
return false;
}
*wsize=(uint16_t)v;
if (p && *p)
{
v = atoi(p);
if (v < 0 || v>255)
{
fprintf(stderr, "bad wscale\n");
return false;
}
*wscale = (uint8_t)v;
}
return true;
}
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static void exithelp()
{
printf(
" --debug=0|1\n"
#ifdef __linux__
" --qnum=<nfqueue_number>\n"
#elif defined(BSD)
" --port=<port>\t\t\t\t; divert port\n"
#endif
" --daemon\t\t\t\t; daemonize\n"
" --pidfile=<filename>\t\t\t; write pid to file\n"
" --user=<username>\t\t\t; drop root privs\n"
" --uid=uid[:gid]\t\t\t; drop root privs\n"
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" --wsize=<window_size>[:<scale_factor>]\t; set window size. 0 = do not modify. OBSOLETE !\n"
" --wssize=<window_size>[:<scale_factor>]; set window size for server. 0 = do not modify.\n"
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" --hostcase\t\t\t\t; change Host: => host:\n"
" --hostspell\t\t\t\t; exact spelling of \"Host\" header. must be 4 chars. default is \"host\"\n"
" --hostnospace\t\t\t\t; remove space after Host: and add it to User-Agent: to preserve packet size\n"
" --domcase\t\t\t\t; mix domain case : Host: TeSt.cOm\n"
" --dpi-desync=<mode>[,<mode2>]\t\t; try to desync dpi state. modes : fake rst rstack disorder disorder2 split split2\n"
#ifdef __linux__
" --dpi-desync-fwmark=<int|0xHEX>\t; override fwmark for desync packet. default = 0x%08X (%u)\n"
#elif defined(SO_USER_COOKIE)
" --dpi-desync-sockarg=<int|0xHEX>\t; override sockarg (SO_USER_COOKIE) for desync packet. default = 0x%08X (%u)\n"
#endif
" --dpi-desync-ttl=<int>\t\t\t; set ttl for desync packet\n"
" --dpi-desync-fooling=<mode>[,<mode>]\t; can use multiple comma separated values. modes : none md5sig ts badseq badsum\n"
#ifdef __linux__
" --dpi-desync-retrans=0|1\t\t; 0(default)=reinject original data packet after fake 1=drop original data packet to force its retransmission\n"
#endif
" --dpi-desync-repeats=<N>\t\t; send every desync packet N times\n"
" --dpi-desync-skip-nosni=0|1\t\t; 1(default)=do not act on ClientHello without SNI (ESNI ?)\n"
" --dpi-desync-split-pos=<1..%u>\t; (for disorder only) split TCP packet at specified position\n"
" --dpi-desync-any-protocol=0|1\t\t; 0(default)=desync only http and tls 1=desync any nonempty data packet\n"
" --dpi-desync-fake-http=<filename>\t; file containing fake http request\n"
" --dpi-desync-fake-tls=<filename>\t; file containing fake TLS ClientHello (for https)\n"
" --hostlist=<filename>\t\t\t; apply dpi desync only to the listed hosts (one host per line, subdomains auto apply)\n",
#if defined(__linux__) || defined(SO_USER_COOKIE)
DPI_DESYNC_FWMARK_DEFAULT,DPI_DESYNC_FWMARK_DEFAULT,
#endif
DPI_DESYNC_MAX_FAKE_LEN
);
exit(1);
}
static void cleanup_params()
{
if (params.hostlist)
{
StrPoolDestroy(&params.hostlist);
params.hostlist = NULL;
}
}
static void exithelp_clean()
{
cleanup_params();
exithelp();
}
static void exit_clean(int code)
{
cleanup_params();
exit(code);
}
int main(int argc, char **argv)
{
int result, v;
int option_index = 0;
bool daemon = false;
char pidfile[256];
srandom(time(NULL));
memset(&params, 0, sizeof(params));
memcpy(params.hostspell, "host", 4); // default hostspell
*pidfile = 0;
params.desync_fwmark = DPI_DESYNC_FWMARK_DEFAULT;
params.desync_skip_nosni = true;
params.desync_split_pos = 3;
params.desync_repeats = 1;
params.fake_tls_size = sizeof(fake_tls_clienthello_default);
memcpy(params.fake_tls,fake_tls_clienthello_default,params.fake_tls_size);
params.fake_http_size = strlen(fake_http_request_default);
memcpy(params.fake_http,fake_http_request_default,params.fake_http_size);
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params.wscale=-1; // default - dont change scale factor (client)
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if (can_drop_root()) // are we root ?
{
params.uid = params.gid = 0x7FFFFFFF; // default uid:gid
params.droproot = true;
}
const struct option long_options[] = {
{"debug",optional_argument,0,0}, // optidx=0
#ifdef __linux__
{"qnum",required_argument,0,0}, // optidx=1
#elif defined(BSD)
{"port",required_argument,0,0}, // optidx=1
#else
{"disabled_argument_1",no_argument,0,0},// optidx=1
#endif
{"daemon",no_argument,0,0}, // optidx=2
{"pidfile",required_argument,0,0}, // optidx=3
{"user",required_argument,0,0 }, // optidx=4
{"uid",required_argument,0,0 }, // optidx=5
{"wsize",required_argument,0,0}, // optidx=6
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{"wssize",required_argument,0,0}, // optidx=7
{"hostcase",no_argument,0,0}, // optidx=8
{"hostspell",required_argument,0,0}, // optidx=9
{"hostnospace",no_argument,0,0}, // optidx=10
{"domcase",no_argument,0,0 }, // optidx=11
{"dpi-desync",required_argument,0,0}, // optidx=12
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#ifdef __linux__
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{"dpi-desync-fwmark",required_argument,0,0}, // optidx=13
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#elif defined(SO_USER_COOKIE)
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{"dpi-desync-sockarg",required_argument,0,0}, // optidx=13
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#else
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{"disabled_argument_2",no_argument,0,0}, // optidx=13
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#endif
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{"dpi-desync-ttl",required_argument,0,0}, // optidx=14
{"dpi-desync-fooling",required_argument,0,0}, // optidx=15
{"dpi-desync-retrans",optional_argument,0,0}, // optidx=16
{"dpi-desync-repeats",required_argument,0,0}, // optidx=17
{"dpi-desync-skip-nosni",optional_argument,0,0},// optidx=18
{"dpi-desync-split-pos",required_argument,0,0},// optidx=19
{"dpi-desync-any-protocol",optional_argument,0,0},// optidx=20
{"dpi-desync-fake-http",required_argument,0,0},// optidx=21
{"dpi-desync-fake-tls",required_argument,0,0},// optidx=22
{"hostlist",required_argument,0,0}, // optidx=23
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{NULL,0,NULL,0}
};
if (argc < 2) exithelp();
while ((v = getopt_long_only(argc, argv, "", long_options, &option_index)) != -1)
{
if (v) exithelp();
switch (option_index)
{
case 0: /* debug */
params.debug = !optarg || atoi(optarg);
break;
case 1: /* qnum or port */
#ifdef __linux__
params.qnum = atoi(optarg);
if (params.qnum < 0 || params.qnum>65535)
{
fprintf(stderr, "bad qnum\n");
exit_clean(1);
}
#elif defined(BSD)
{
int i = atoi(optarg);
if (i <= 0 || i > 65535)
{
fprintf(stderr, "bad port number\n");
exit_clean(1);
}
params.port = (uint16_t)i;
}
#endif
break;
case 2: /* daemon */
daemon = true;
break;
case 3: /* pidfile */
strncpy(pidfile, optarg, sizeof(pidfile));
pidfile[sizeof(pidfile) - 1] = '\0';
break;
case 4: /* user */
{
struct passwd *pwd = getpwnam(optarg);
if (!pwd)
{
fprintf(stderr, "non-existent username supplied\n");
exit_clean(1);
}
params.uid = pwd->pw_uid;
params.gid = pwd->pw_gid;
params.droproot = true;
break;
}
case 5: /* uid */
params.gid = 0x7FFFFFFF; // default gid. drop gid=0
params.droproot = true;
if (!sscanf(optarg, "%u:%u", &params.uid, &params.gid))
{
fprintf(stderr, "--uid should be : uid[:gid]\n");
exit_clean(1);
}
break;
case 6: /* wsize */
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if (!parse_scale_factor(optarg,&params.wsize,&params.wscale))
exit_clean(1);
break;
case 7: /* wssize */
if (!parse_scale_factor(optarg,&params.wssize,&params.wsscale))
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exit_clean(1);
break;
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case 8: /* hostcase */
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params.hostcase = true;
break;
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case 9: /* hostspell */
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if (strlen(optarg) != 4)
{
fprintf(stderr, "hostspell must be exactly 4 chars long\n");
exit_clean(1);
}
params.hostcase = true;
memcpy(params.hostspell, optarg, 4);
break;
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case 10: /* hostnospace */
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params.hostnospace = true;
break;
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case 11: /* domcase */
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params.domcase = true;
break;
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case 12: /* dpi-desync */
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{
char *mode2;
mode2 = optarg ? strchr(optarg,',') : NULL;
if (mode2) *mode2++=0;
params.desync_mode = desync_mode_from_string(optarg);
params.desync_mode2 = desync_mode_from_string(mode2);
if (params.desync_mode==DESYNC_NONE || params.desync_mode==DESYNC_INVALID || params.desync_mode2==DESYNC_INVALID)
{
fprintf(stderr, "invalid dpi-desync mode\n");
exit_clean(1);
}
if (params.desync_mode2 && !(desync_valid_first_stage(params.desync_mode) && desync_valid_second_stage(params.desync_mode2)))
{
fprintf(stderr, "invalid desync combo : %s+%s\n", optarg,mode2);
exit_clean(1);
}
}
break;
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case 13: /* dpi-desync-fwmark/dpi-desync-sockarg */
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#if defined(__linux__) || defined(SO_USER_COOKIE)
params.desync_fwmark = 0;
if (!sscanf(optarg, "0x%X", &params.desync_fwmark)) sscanf(optarg, "%u", &params.desync_fwmark);
if (!params.desync_fwmark)
{
fprintf(stderr, "fwmark/sockarg should be decimal or 0xHEX and should not be zero\n");
exit_clean(1);
}
#else
fprintf(stderr, "fmwark/sockarg not supported in this OS\n");
exit_clean(1);
#endif
break;
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case 14: /* dpi-desync-ttl */
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params.desync_ttl = (uint8_t)atoi(optarg);
break;
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case 15: /* dpi-desync-fooling */
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{
char *e,*p = optarg;
while (p)
{
e = strchr(p,',');
if (e) *e++=0;
if (!strcmp(p,"md5sig"))
params.desync_tcp_fooling_mode |= TCP_FOOL_MD5SIG;
else if (!strcmp(p,"ts"))
params.desync_tcp_fooling_mode |= TCP_FOOL_TS;
else if (!strcmp(p,"badsum"))
{
#ifdef __OpenBSD__
printf("\nWARNING !!! OpenBSD may forcibly recompute tcp checksums !!! In this case badsum fooling will not work.\nYou should check tcp checksum correctness in tcpdump manually before using badsum.\n\n");
#endif
params.desync_tcp_fooling_mode |= TCP_FOOL_BADSUM;
}
else if (!strcmp(p,"badseq"))
params.desync_tcp_fooling_mode |= TCP_FOOL_BADSEQ;
else if (strcmp(p,"none"))
{
fprintf(stderr, "dpi-desync-fooling allowed values : none,md5sig,ts,badseq,badsum\n");
exit_clean(1);
}
p = e;
}
}
break;
2021-03-12 11:33:48 +00:00
case 16: /* dpi-desync-retrans */
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#ifdef __linux__
params.desync_retrans = !optarg || atoi(optarg);
#else
fprintf(stderr, "dpi-desync-retrans is only supported in linux\n");
exit_clean(1);
#endif
break;
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case 17: /* dpi-desync-repeats */
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params.desync_repeats = atoi(optarg);
if (params.desync_repeats<=0 || params.desync_repeats>20)
{
fprintf(stderr, "dpi-desync-repeats must be within 1..20\n");
exit_clean(1);
}
break;
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case 18: /* dpi-desync-skip-nosni */
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params.desync_skip_nosni = !optarg || atoi(optarg);
break;
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case 19: /* dpi-desync-split-pos */
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params.desync_split_pos = atoi(optarg);
if (params.desync_split_pos<1 || params.desync_split_pos>DPI_DESYNC_MAX_FAKE_LEN)
{
fprintf(stderr, "dpi-desync-split-pos must be within 1..%u range\n",DPI_DESYNC_MAX_FAKE_LEN);
exit_clean(1);
}
break;
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case 20: /* dpi-desync-any-protocol */
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params.desync_any_proto = !optarg || atoi(optarg);
break;
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case 21: /* dpi-desync-fake-http */
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params.fake_http_size = sizeof(params.fake_http);
if (!load_file_nonempty(optarg,params.fake_http,&params.fake_http_size))
{
fprintf(stderr, "could not read %s\n",optarg);
exit_clean(1);
}
break;
2021-03-12 11:33:48 +00:00
case 22: /* dpi-desync-fake-tls */
2021-03-04 11:30:38 +00:00
params.fake_tls_size = sizeof(params.fake_tls);
if (!load_file_nonempty(optarg,params.fake_tls,&params.fake_tls_size))
{
fprintf(stderr, "could not read %s\n",optarg);
exit_clean(1);
}
break;
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case 23: /* hostlist */
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if (!LoadHostList(&params.hostlist, optarg))
exit_clean(1);
strncpy(params.hostfile,optarg,sizeof(params.hostfile));
params.hostfile[sizeof(params.hostfile)-1]='\0';
break;
}
}
#ifdef BSD
if (!params.port)
{
fprintf(stderr, "Need port number\n");
exit_clean(1);
}
#endif
if (daemon) daemonize();
if (*pidfile && !writepid(pidfile))
{
fprintf(stderr, "could not write pidfile\n");
goto exiterr;
}
#ifdef __linux__
result = nfq_main();
#elif defined(BSD)
result = dvt_main();
#else
#error unsupported OS
#endif
ex:
rawsend_cleanup();
cleanup_params();
return result;
exiterr:
result = 1;
goto ex;
}