/*
* $Id$
*
* Copyright (C) 2001-2003 Fhg Fokus
*
* This file is part of ser, a free SIP server.
*
* ser is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version
*
* For a license to use the ser software under conditions
* other than those described here, or to purchase support for this
* software, please contact iptel.org by e-mail at the following addresses:
* info@iptel.org
*
* ser 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, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
/*
* History:
* --------
* 2002-12-?? created by andrei.
* 2003-02-10 zero term before calling receive_msg & undo afterwards (andrei)
* 2003-05-13 l: (short form of Content-Length) is now recognized (andrei)
*/
#ifdef USE_TCP
#include <stdio.h>
#include <errno.h>
#include <string.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/select.h>
#include <sys/socket.h>
#include <unistd.h>
#include <stdlib.h> /* for abort() */
#include "dprint.h"
#include "tcp_conn.h"
#include "pass_fd.h"
#include "globals.h"
#include "receive.h"
#include "timer.h"
#include "ut.h"
/* reads next available bytes
* return number of bytes read, 0 on EOF or -1 on error,
* sets also r->error */
int tcp_read(struct tcp_req *r, int fd)
{
int bytes_free, bytes_read;
bytes_free=TCP_BUF_SIZE- (int)(r->pos - r->buf);
if (bytes_free==0){
LOG(L_ERR, "ERROR: tcp_read: buffer overrun, dropping\n");
r->error=TCP_REQ_OVERRUN;
return -1;
}
again:
bytes_read=read(fd, r->pos, bytes_free);
if(bytes_read==-1){
if (errno == EWOULDBLOCK || errno == EAGAIN){
return 0; /* nothing has been read */
}else if (errno == EINTR) goto again;
else{
LOG(L_ERR, "ERROR: tcp_read: error reading: %s\n",strerror(errno));
r->error=TCP_READ_ERROR;
return -1;
}
}
#ifdef EXTRA_DEBUG
DBG("tcp_read: read %d bytes:\n%.*s\n", bytes_read, bytes_read, r->pos);
#endif
r->pos+=bytes_read;
return bytes_read;
}
/* reads all headers (until double crlf), & parses the content-length header
* (WARNING: ineficient, tries to reuse receive_msg but will go through
* the headers twice [once here looking for Content-Length and for the end
* of the headers and once in receive_msg]; a more speed eficient version will
* result in either major code duplication or major changes to the receive code)
* returns number of bytes read & sets r->state & r->body
* when either r->body!=0 or r->state==H_BODY =>
* all headers have been read. It should be called in a while loop.
* returns < 0 if error or 0 if EOF */
int tcp_read_headers(struct tcp_req *r, int fd)
{
int bytes, remaining;
char *p;
#define crlf_default_skip_case \
case '\n': \
r->state=H_LF; \
break; \
default: \
r->state=H_SKIP
#define content_len_beg_case \
case ' ': \
case '\t': \
if (!r->has_content_len) r->state=H_STARTWS; \
else r->state=H_SKIP; \
/* not interested if we already found one */ \
break; \
case 'C': \
case 'c': \
if(!r->has_content_len) r->state=H_CONT_LEN1; \
else r->state=H_SKIP; \
break; \
case 'l': \
case 'L': \
/* short form for Content-Length */ \
if (!r->has_content_len) r->state=H_L_COLON; \
else r->state=H_SKIP; \
break
#define change_state(upper, lower, newstate)\
switch(*p){ \
case upper: \
case lower: \
r->state=(newstate); break; \
crlf_default_skip_case; \
}
#define change_state_case(state0, upper, lower, newstate)\
case state0: \
change_state(upper, lower, newstate); \
p++; \
break
/* if we still have some unparsed part, parse it first, don't do the read*/
if (r->parsed<r->pos){
bytes=0;
}else{
bytes=tcp_read(r, fd);
if (bytes<=0) return bytes;
}
p=r->parsed;
while(p<r->pos && r->error==TCP_REQ_OK){
switch((unsigned char)r->state){
case H_BODY: /* read the body*/
remaining=r->pos-p;
if (remaining>r->bytes_to_go) remaining=r->bytes_to_go;
r->bytes_to_go-=remaining;
p+=remaining;
if (r->bytes_to_go==0){
r->complete=1;
goto skip;
}
break;
case H_SKIP:
/* find lf, we are in this state if we are not interested
* in anything till end of line*/
p=q_memchr(p, '\n', r->pos-p);
if (p){
p++;
r->state=H_LF;
}else{
p=r->pos;
}
break;
case H_LF:
/* terminate on LF CR LF or LF LF */
switch (*p){
case '\r':
r->state=H_LFCR;
break;
case '\n':
/* found LF LF */
r->state=H_BODY;
if (r->has_content_len){
r->body=p+1;
r->bytes_to_go=r->content_len;
if (r->bytes_to_go==0){
r->complete=1;
p++;
goto skip;
}
}else{
DBG("tcp_read_headers: ERROR: no clen, p=%X\n",
*p);
r->error=TCP_REQ_BAD_LEN;
}
break;
content_len_beg_case;
default:
r->state=H_SKIP;
}
p++;
break;
case H_LFCR:
if (*p=='\n'){
/* found LF CR LF */
r->state=H_BODY;
if (r->has_content_len){
r->body=p+1;
r->bytes_to_go=r->content_len;
if (r->bytes_to_go==0){
r->complete=1;
p++;
goto skip;
}
}else{
DBG("tcp_read_headers: ERROR: no clen, p=%X\n",
*p);
r->error=TCP_REQ_BAD_LEN;
}
}else r->state=H_SKIP;
p++;
break;
case H_STARTWS:
switch (*p){
content_len_beg_case;
crlf_default_skip_case;
}
p++;
break;
case H_SKIP_EMPTY:
switch (*p){
case '\n':
case '\r':
case ' ':
case '\t':
/* skip empty lines */
break;
case 'C':
case 'c':
r->state=H_CONT_LEN1;
r->start=p;
break;
case 'l':
case 'L':
/* short form for Content-Length */
r->state=H_L_COLON;
r->start=p;
break;
default:
r->state=H_SKIP;
r->start=p;
};
p++;
break;
change_state_case(H_CONT_LEN1, 'O', 'o', H_CONT_LEN2);
change_state_case(H_CONT_LEN2, 'N', 'n', H_CONT_LEN3);
change_state_case(H_CONT_LEN3, 'T', 't', H_CONT_LEN4);
change_state_case(H_CONT_LEN4, 'E', 'e', H_CONT_LEN5);
change_state_case(H_CONT_LEN5, 'N', 'n', H_CONT_LEN6);
change_state_case(H_CONT_LEN6, 'T', 't', H_CONT_LEN7);
change_state_case(H_CONT_LEN7, '-', '_', H_CONT_LEN8);
change_state_case(H_CONT_LEN8, 'L', 'l', H_CONT_LEN9);
change_state_case(H_CONT_LEN9, 'E', 'e', H_CONT_LEN10);
change_state_case(H_CONT_LEN10, 'N', 'n', H_CONT_LEN11);
change_state_case(H_CONT_LEN11, 'G', 'g', H_CONT_LEN12);
change_state_case(H_CONT_LEN12, 'T', 't', H_CONT_LEN13);
change_state_case(H_CONT_LEN13, 'H', 'h', H_L_COLON);
case H_L_COLON:
switch(*p){
case ' ':
case '\t':
break; /* skip space */
case ':':
r->state=H_CONT_LEN_BODY;
break;
crlf_default_skip_case;
};
p++;
break;
case H_CONT_LEN_BODY:
switch(*p){
case ' ':
case '\t':
break; /* eat space */
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
r->state=H_CONT_LEN_BODY_PARSE;
r->content_len=(*p-'0');
break;
/*FIXME: content lenght on different lines ! */
crlf_default_skip_case;
}
p++;
break;
case H_CONT_LEN_BODY_PARSE:
switch(*p){
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
r->content_len=r->content_len*10+(*p-'0');
break;
case '\r':
case ' ':
case '\t': /* FIXME: check if line contains only WS */
r->state=H_SKIP;
r->has_content_len=1;
break;
case '\n':
/* end of line, parse succesfull */
r->state=H_LF;
r->has_content_len=1;
break;
default:
LOG(L_ERR, "ERROR: tcp_read_headers: bad "
"Content-Length header value, unexpected "
"char %c in state %d\n", *p, r->state);
r->state=H_SKIP; /* try to find another?*/
}
p++;
break;
default:
LOG(L_CRIT, "BUG: tcp_read_headers: unexpected state %d\n",
r->state);
abort();
}
}
skip:
r->parsed=p;
return bytes;
}
int tcp_read_req(struct tcp_connection* con)
{
int bytes;
int resp;
long size;
struct tcp_req* req;
int s;
char c;
resp=CONN_RELEASE;
s=con->fd;
req=&con->req;
size=0;
again:
if(req->complete==0 && req->error==TCP_REQ_OK){
bytes=tcp_read_headers(req, s);
#ifdef EXTRA_DEBUG
/* if timeout state=0; goto end__req; */
DBG("read= %d bytes, parsed=%d, state=%d, error=%d\n",
bytes, (int)(req->parsed-req->start), req->state,
req->error );
DBG("tcp_read_req: last char=%X, parsed msg=\n%.*s\n",
*(req->parsed-1), (int)(req->parsed-req->start),
req->start);
#endif
if (bytes==-1){
LOG(L_ERR, "ERROR: tcp_read_req: error reading \n");
resp=CONN_ERROR;
goto end_req;
}
if ((size==0) && (bytes==0)){
DBG( "tcp_read_req: EOF\n");
resp=CONN_EOF;
goto end_req;
}
}
if (req->error!=TCP_REQ_OK){
LOG(L_ERR,"ERROR: tcp_read_req: bad request, state=%d, error=%d "
"buf:\n%.*s\nparsed:\n%.*s\n", req->state, req->error,
(int)(req->pos-req->buf), req->buf,
(int)(req->parsed-req->start), req->start);
DBG("- received from: port %d, ip -", con->rcv.src_port);
print_ip(&con->rcv.src_ip); DBG("-\n");
resp=CONN_ERROR;
goto end_req;
}
if (req->complete){
#ifdef EXTRA_DEBUG
DBG("tcp_read_req: end of header part\n");
DBG("- received from: port %d, ip - ", con->rcv.src_port);
print_ip(&con->rcv.src_ip); DBG("-\n");
DBG("tcp_read_req: headers:\n%.*s.\n",
(int)(req->body-req->start), req->start);
#endif
if (req->has_content_len){
DBG("tcp_read_req: content-length= %d\n", req->content_len);
#ifdef EXTRA_DEBUG
DBG("tcp_read_req: body:\n%.*s\n", req->content_len,req->body);
#endif
}else{
req->error=TCP_REQ_BAD_LEN;
LOG(L_ERR, "ERROR: tcp_read_req: content length not present or"
" unparsable\n");
resp=CONN_ERROR;
goto end_req;
}
/* if we are here everything is nice and ok*/
resp=CONN_RELEASE;
#ifdef EXTRA_DEBUG
DBG("calling receive_msg(%p, %d, )\n",
req->start, (int)(req->parsed-req->start));
#endif
/* rcv.bind_address should always be !=0 */
bind_address=con->rcv.bind_address;
/* just for debugging use sendipv4 as receiving socket FIXME*/
/*
if (con->rcv.dst_ip.af==AF_INET6){
bind_address=sendipv6_tcp;
}else{
bind_address=sendipv4_tcp;
}
*/
con->rcv.proto_reserved1=con->id; /* copy the id */
c=*req->parsed; /* ugly hack: zero term the msg & save the
previous char, req->parsed should be ok
because we always alloc BUF_SIZE+1 */
*req->parsed=0;
if (receive_msg(req->start, req->parsed-req->start, &con->rcv)<0){
*req->parsed=c;
resp=CONN_ERROR;
goto end_req;
}
*req->parsed=c;
/* prepare for next request */
size=req->pos-req->parsed;
if (size) memmove(req->buf, req->parsed, size);
#ifdef EXTRA_DEBUG
DBG("tcp_read_req: preparing for new request, kept %ld bytes\n",
size);
#endif
req->pos=req->buf+size;
req->parsed=req->buf;
req->start=req->buf;
req->body=0;
req->error=TCP_REQ_OK;
req->state=H_SKIP_EMPTY;
req->complete=req->content_len=req->has_content_len=0;
req->bytes_to_go=0;
/* if we still have some unparsed bytes, try to parse them too*/
if (size) goto again;
}
end_req:
return resp;
}
void release_tcpconn(struct tcp_connection* c, long state, int unix_sock)
{
long response[2];
DBG( "releasing con %p, state %ld, fd=%d, id=%d\n",
c, state, c->fd, c->id);
/* release req & signal the parent */
if (c->fd!=-1) close(c->fd);
/* errno==EINTR, EWOULDBLOCK a.s.o todo */
response[0]=(long)c;
response[1]=state;
write(unix_sock, response, sizeof(response));
}
void tcp_receive_loop(int unix_sock)
{
struct tcp_connection* list; /* list with connections in use */
struct tcp_connection* con;
struct tcp_connection* c_next;
int n;
int nfds;
int s;
long resp;
fd_set master_set;
fd_set sel_set;
int maxfd;
struct timeval timeout;
int ticks;
/* init */
list=con=0;
FD_ZERO(&master_set);
FD_SET(unix_sock, &master_set);
maxfd=unix_sock;
/* listen on the unix socket for the fd */
for(;;){
timeout.tv_sec=TCP_CHILD_SELECT_TIMEOUT;
timeout.tv_usec=0;
sel_set=master_set;
nfds=select(maxfd+1, &sel_set, 0 , 0 , &timeout);
#ifdef EXTRA_DEBUG
for (n=0; n<maxfd; n++){
if (FD_ISSET(n, &sel_set))
DBG("tcp receive: FD %d is set\n", n);
}
#endif
if (nfds<0){
if (errno==EINTR) continue; /* just a signal */
/* errors */
LOG(L_ERR, "ERROR: tcp_receive_loop: select:(%d) %s\n", errno,
strerror(errno));
continue;
}
if (FD_ISSET(unix_sock, &sel_set)){
nfds--;
/* a new conn from "main" */
n=receive_fd(unix_sock, &con, sizeof(con), &s);
if (n<0){
if (errno == EWOULDBLOCK || errno == EAGAIN ||
errno == EINTR){
continue;
}else{
LOG(L_CRIT,"BUG: tcp_receive_loop: read_fd: %s\n",
strerror(errno));
abort(); /* big error*/
}
}
if (n==0){
LOG(L_ERR, "WARNING: tcp_receive_loop: 0 bytes read\n");
continue;
}
con->fd=s;
DBG("received n=%d con=%p, fd=%d\n", n, con, s);
if (s==-1) {
LOG(L_ERR, "ERROR: tcp_receive_loop: read_fd:"
"no fd read\n");
resp=CONN_ERROR;
con->bad=1;
release_tcpconn(con, resp, unix_sock);
}
if (con==0){
LOG(L_ERR, "ERROR: tcp_receive_loop: null pointer\n");
resp=CONN_ERROR;
con->bad=1;
release_tcpconn(con, resp, unix_sock);
}
con->timeout=get_ticks()+TCP_CHILD_TIMEOUT;
FD_SET(s, &master_set);
if (maxfd<s) maxfd=s;
tcpconn_listadd(list, con, c_next, c_prev);
}
ticks=get_ticks();
for (con=list; con ; con=c_next){
c_next=con->c_next; /* safe for removing*/
#ifdef EXTRA_DEBUG
DBG("tcp receive: list fd=%d, id=%d, timeout=%d, refcnt=%d\n",
con->fd, con->id, con->timeout, con->refcnt);
#endif
if (nfds && FD_ISSET(con->fd, &sel_set)){
#ifdef EXTRA_DEBUG
DBG("tcp receive: match, fd:isset\n");
#endif
nfds--;
resp=tcp_read_req(con);
if (resp<0){
FD_CLR(con->fd, &master_set);
tcpconn_listrm(list, con, c_next, c_prev);
con->bad=1;
release_tcpconn(con, resp, unix_sock);
}else{
/* update timeout */
con->timeout=ticks+TCP_CHILD_TIMEOUT;
}
}else{
/* timeout */
if (con->timeout<=ticks){
/* expired, return to "tcp main" */
DBG("tcp_receive_loop: %p expired (%d, %d)\n",
con, con->timeout, ticks);
resp=CONN_RELEASE;
FD_CLR(con->fd, &master_set);
tcpconn_listrm(list, con, c_next, c_prev);
release_tcpconn(con, resp, unix_sock);
}
}
}
}
}
#if 0
int main(int argv, char** argc )
{
printf("starting tests\n");
tcp_receive_loop();
}
#endif
#endif