3proxy/src/ftppr.c
2021-07-02 11:50:33 +03:00

337 lines
11 KiB
C

/*
3APA3A simpliest proxy server
(c) 2002-2021 by Vladimir Dubrovin <3proxy@3proxy.org>
please read License Agreement
*/
#include "proxy.h"
#define RETURN(xxx) { param->res = xxx; goto CLEANRET; }
#define BUFSIZE 2048
void * ftpprchild(struct clientparam* param) {
int i=0, res;
unsigned char *buf;
unsigned char *se;
int status = 0;
int inbuf;
int pasv = 0;
SOCKET sc = INVALID_SOCKET, ss = INVALID_SOCKET, clidatasock = INVALID_SOCKET;
SASIZETYPE sasize;
char * req = NULL;
struct linger lg;
struct pollfd fds;
if(!(buf = myalloc(BUFSIZE))) RETURN(876);
param->ctrlsock = param->clisock;
param->operation = CONNECT;
lg.l_onoff = 1;
lg.l_linger = conf.timeouts[STRING_L];;
if(socksend(param->ctrlsock, (unsigned char *)"220 Ready\r\n", 11, conf.timeouts[STRING_S])!=11) {RETURN (801);}
for(;;){
i = sockgetlinebuf(param, CLIENT, buf, BUFSIZE - 10, '\n', conf.timeouts[CONNECTION_S]);
if(!i) {
RETURN(0);
}
if(i<4) {RETURN(802);}
buf[i] = 0;
if ((se=(unsigned char *)strchr((char *)buf, '\r'))) *se = 0;
if (req) myfree (req);
req = NULL;
if (!strncasecmp((char *)buf, "OPEN ", 5)){
if(parsehostname((char *)buf+5, param, 21)){RETURN(803);}
if(param->remsock != INVALID_SOCKET) {
so._shutdown(param->remsock, SHUT_RDWR);
so._closesocket(param->remsock);
param->remsock = INVALID_SOCKET;
}
if((res = (*param->srv->authfunc)(param))) {RETURN(res);}
param->ctrlsocksrv = param->remsock;
if(socksend(param->ctrlsock, (unsigned char *)"220 Ready\r\n", 11, conf.timeouts[STRING_S])!=11) {RETURN (801);}
status = 1;
}
else if (!strncasecmp((char *)buf, "USER ", 5)){
if(parseconnusername((char *)buf +5, param, 0, 21)){RETURN(804);}
if(!status){
if((res = (*param->srv->authfunc)(param))) {RETURN(res);}
param->ctrlsocksrv = param->remsock;
}
if(socksend(param->ctrlsock, (unsigned char *)"331 ok\r\n", 8, conf.timeouts[STRING_S])!=8) {RETURN (807);}
status = 2;
}
else if (!strncasecmp((char *)buf, "PASS ", 5)){
param->extpassword = (unsigned char *)mystrdup((char *)buf+5);
inbuf = BUFSIZE;
res = ftplogin(param, (char *)buf, &inbuf);
param->res = res;
if(inbuf && inbuf != BUFSIZE && socksend(param->ctrlsock, buf, inbuf, conf.timeouts[STRING_S])!=inbuf) {RETURN (807);}
if(!res) status = 3;
sprintf((char *)buf, "%.128s@%.128s%c%hu", param->extusername, param->hostname, (ntohs(*SAPORT(&param->sinsr))==21)?0:':', ntohs(*SAPORT(&param->sinsr)));
req = mystrdup((char *)buf);
#ifndef WITHMAIN
{
int action, reqbufsize, reqsize;
reqbufsize = BUFSIZE;
reqsize = (int)strlen((char *)buf) + 1;
action = handlereqfilters(param, &buf, &reqbufsize, 0, &reqsize);
if(action == HANDLED){
RETURN(0);
}
if(action != PASS) RETURN(877);
}
#endif
}
else if (status >= 3 && (
(!strncasecmp((char *)buf, "PASV", 4) && (pasv = 1)) ||
(!strncasecmp((char *)buf, "EPSV", 4) && (pasv = 2)) ||
(!strncasecmp((char *)buf, "PORT ", 5) && !(pasv = 0))
)){
#ifndef WITHMAIN
{
int action, reqbufsize, reqsize;
reqbufsize = BUFSIZE;
reqsize = (int)strlen((char *)buf) + 1;
action = handlehdrfilterscli(param, &buf, &reqbufsize, 0, &reqsize);
if(action == HANDLED){
RETURN(0);
}
if(action != PASS) RETURN(878);
}
#endif
if(sc != INVALID_SOCKET) {
so._shutdown(sc, SHUT_RDWR);
so._closesocket(sc);
sc = INVALID_SOCKET;
}
if(ss != INVALID_SOCKET) {
so._shutdown(ss, SHUT_RDWR);
so._closesocket(ss);
ss = INVALID_SOCKET;
}
if(clidatasock != INVALID_SOCKET) {
so._shutdown(clidatasock, SHUT_RDWR);
so._closesocket(clidatasock);
clidatasock = INVALID_SOCKET;
}
if ((clidatasock=socket(SASOCK(&param->sincl), SOCK_STREAM, IPPROTO_TCP)) == INVALID_SOCKET) {RETURN(821);}
*SAPORT(&param->sincl) = 0;
if(so._bind(clidatasock, (struct sockaddr *)&param->sincl, SASIZE(&param->sincl))){RETURN(822);}
if (pasv) {
if(so._listen(clidatasock, 1)) {RETURN(823);}
sasize = sizeof(param->sincl);
if(so._getsockname(clidatasock, (struct sockaddr *)&param->sincl, &sasize)){RETURN(824);}
if(pasv == 1){
if(*SAFAMILY(&param->sincl) == AF_INET)
sprintf((char *)buf, "227 OK (%u,%u,%u,%u,%u,%u)\r\n",
(unsigned)(((unsigned char *)(SAADDR(&param->sincl)))[0]),
(unsigned)(((unsigned char *)(SAADDR(&param->sincl)))[1]),
(unsigned)(((unsigned char *)(SAADDR(&param->sincl)))[2]),
(unsigned)(((unsigned char *)(SAADDR(&param->sincl)))[3]),
(unsigned)(((unsigned char *)(SAPORT(&param->sincl)))[0]),
(unsigned)(((unsigned char *)(SAPORT(&param->sincl)))[1])
);
else sprintf((char *)buf, "227 OK (127,0,0,1,%u,%u)\r\n",
(unsigned)(((unsigned char *)(SAPORT(&param->sincl)))[0]),
(unsigned)(((unsigned char *)(SAPORT(&param->sincl)))[1])
);
}
else {
sprintf((char *)buf, "229 OK (|||%u|)\r\n",
(unsigned)ntohs(*SAPORT(&param->sincl))
);
}
}
else {
unsigned long b1, b2, b3, b4;
unsigned short b5, b6;
if(sscanf((char *)buf+5, "%lu,%lu,%lu,%lu,%hu,%hu", &b1, &b2, &b3, &b4, &b5, &b6)!=6) {RETURN(828);}
*SAPORT(&param->sincr) = htons((unsigned short)((b5<<8)^b6));
if(connectwithpoll(clidatasock, (struct sockaddr *)&param->sincr, SASIZE(&param->sincr),CONNECT_TO)) {
so._closesocket(clidatasock);
clidatasock = INVALID_SOCKET;
RETURN(826);
}
sprintf((char *)buf, "200 OK\r\n");
}
#ifndef WITHMAIN
{
int action, reqbufsize, reqsize;
reqbufsize = BUFSIZE;
reqsize = (int)strlen((char *)buf) + 1;
action = handlehdrfilterssrv(param, &buf, &reqbufsize, 0, &reqsize);
if(action == HANDLED){
RETURN(0);
}
if(action != PASS) RETURN(879);
}
#endif
if(socksend(param->ctrlsock, buf, (int)strlen((char *)buf), conf.timeouts[STRING_S])!=(int)strlen((char *)buf)) {RETURN (825);}
status = 4;
}
else if (status == 4 && (
!(strncasecmp((char *)buf, "RETR ", 5) && (param->operation = FTP_GET)) ||
!(strncasecmp((char *)buf, "LIST", 4) && (param->operation = FTP_LIST))||
!(strncasecmp((char *)buf, "NLST ", 5) && (param->operation = FTP_LIST)) ||
!(strncasecmp((char *)buf, "MLSD", 4) && (param->operation = FTP_LIST)) ||
!(strncasecmp((char *)buf, "APPE ", 5) && (param->operation = FTP_PUT)) ||
!(strncasecmp((char *)buf, "STOR ", 5) && (param->operation = FTP_PUT))
)){
int arg = (buf[4] && buf[5])? 1:0;
int ressent = 0;
#ifndef WITHMAIN
{
int action, reqbufsize, reqsize;
reqbufsize = BUFSIZE;
reqsize = (int)strlen((char *)buf) + 1;
action = handlehdrfilterscli(param, &buf, &reqbufsize, 0, &reqsize);
if(action == HANDLED){
RETURN(0);
}
if(action != PASS) RETURN(880);
}
#endif
if(clidatasock == INVALID_SOCKET) { RETURN (829);}
if(pasv){
memset(&fds, 0, sizeof(fds));
fds.fd = clidatasock;
fds.events = POLLIN;
res = so._poll (&fds, 1, conf.timeouts[STRING_L]*1000);
if(res != 1) {
RETURN(857);
}
sasize = sizeof(param->sincr);
ss = so._accept(clidatasock, (struct sockaddr *)&param->sincr, &sasize);
if (ss == INVALID_SOCKET) { RETURN (858);}
so._shutdown(clidatasock, SHUT_RDWR);
so._closesocket(clidatasock);
clidatasock = ss;
ss = INVALID_SOCKET;
}
if(clidatasock == INVALID_SOCKET){RETURN(828);}
req = mystrdup((char *)buf);
buf[4] = 0;
status = 3;
ss = ftpcommand(param, buf, arg? buf+5 : NULL);
if (ss == INVALID_SOCKET) {
so._shutdown(clidatasock, SHUT_RDWR);
so._closesocket(clidatasock);
clidatasock = INVALID_SOCKET;
if(socksend(param->ctrlsock, (unsigned char *)"550 err\r\n", 9, conf.timeouts[STRING_S])!=9) {RETURN (831);}
continue;
}
if(socksend(param->ctrlsock, (unsigned char *)"125 data\r\n", 10, conf.timeouts[STRING_S]) != 10) {
param->remsock = INVALID_SOCKET;
RETURN (832);
}
if(param->srvoffset < param->srvinbuf)while((i = sockgetlinebuf(param, SERVER, buf, BUFSIZE, '\n', 0)) > 3){
if(socksend(param->ctrlsock, buf, i, conf.timeouts[STRING_S])!=i) {RETURN(833);}
if(isnumber(*buf) && buf[3] != '-') {
ressent = 1;
break;
}
}
sc = param->remsock;
param->remsock = ss;
so._setsockopt(param->remsock, SOL_SOCKET, SO_LINGER, (char *)&lg, sizeof(lg));
so._setsockopt(clidatasock, SOL_SOCKET, SO_LINGER, (char *)&lg, sizeof(lg));
param->clisock = clidatasock;
res = mapsocket(param, conf.timeouts[CONNECTION_S]);
if(param->remsock != INVALID_SOCKET) {
so._shutdown (param->remsock, SHUT_RDWR);
so._closesocket(param->remsock);
}
if(param->clisock != INVALID_SOCKET) {
so._shutdown (param->clisock, SHUT_RDWR);
so._closesocket(param->clisock);
}
param->clisock = param->ctrlsock;
param->remsock = sc;
sc = INVALID_SOCKET;
ss = INVALID_SOCKET;
clidatasock = INVALID_SOCKET;
if(!ressent){
while((i = sockgetlinebuf(param, SERVER, buf, BUFSIZE, '\n', conf.timeouts[STRING_L])) > 3){
if(socksend(param->ctrlsock, buf, i, conf.timeouts[STRING_S])!=i) {RETURN(833);}
if(isnumber(*buf) && buf[3] != '-') break;
}
if(i < 3) {RETURN(834);}
}
}
else {
if(status < 3) {
if(socksend(param->remsock, (unsigned char *)"530 login\r\n", 11, conf.timeouts[STRING_S])!=1) {RETURN (810);}
continue;
}
if(!strncasecmp((char *)buf, "QUIT", 4)) status = 5;
if(!strncasecmp((char *)buf, "CWD ", 4)) req = mystrdup((char *)buf);
i = (int)strlen((char *)buf);
buf[i++] = '\r';
buf[i++] = '\n';
if(socksend(param->remsock, buf, i, conf.timeouts[STRING_S])!=i) {RETURN (811);}
param->statscli64+=(i);
param->nwrites++;
while((i = sockgetlinebuf(param, SERVER, buf, BUFSIZE, '\n', conf.timeouts[STRING_L])) > 0){
if(socksend(param->ctrlsock, buf, i, conf.timeouts[STRING_S])!=i) {RETURN (812);}
if(i > 4 && isnumber(*buf) && buf[3] != '-') break;
}
if(status == 5) {RETURN (0);}
if(i < 3) {RETURN (813);}
}
sasize = sizeof(param->sincr);
if(so._getpeername(param->ctrlsock, (struct sockaddr *)&param->sincr, &sasize)){RETURN(819);}
if(req && (param->statscli64 || param->statssrv64)){
dolog(param, (unsigned char *)req);
}
}
CLEANRET:
if(sc != INVALID_SOCKET) {
so._shutdown(sc, SHUT_RDWR);
so._closesocket(sc);
}
if(ss != INVALID_SOCKET) {
so._shutdown(ss, SHUT_RDWR);
so._closesocket(ss);
}
if(clidatasock != INVALID_SOCKET) {
so._shutdown(clidatasock, SHUT_RDWR);
so._closesocket(clidatasock);
}
sasize = sizeof(param->sincr);
so._getpeername(param->ctrlsock, (struct sockaddr *)&param->sincr, &sasize);
if(param->res != 0 || param->statscli64 || param->statssrv64 ){
dolog(param, (unsigned char *)((req && (param->res > 802))? req:NULL));
}
if(req) myfree(req);
if(buf) myfree(buf);
freeparam(param);
return (NULL);
}
#ifdef WITHMAIN
struct proxydef childdef = {
ftpprchild,
21,
0,
S_FTPPR,
" -hdefault_host[:port] - use this host and port as default if no host specified\n"
};
#include "proxymain.c"
#endif