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construct/servlink/io.c
jilles 64f2a7eb2c [svn] Merge old trunk r2077,r2079:
- Move closing of servlink control fd to close_connection()
  instead of doing it in exit_local_server(), and make sure
  we first close the data fd and then the control fd.
- Have servlink process ready fds in order net, data, ctrl
  instead of ctrl, data, net.  This seems to fix the problem
  that squit reasons do not show up on the other side of a
  ziplink (by making it send any final SQUIT and/or ERROR
  before noticing the closed control fd).
2007-03-29 13:03:06 -07:00

657 lines
14 KiB
C

/************************************************************************
* IRC - Internet Relay Chat, servlink/io.c
*
* This program 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 1, or (at your option)
* any later version.
*
* 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, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*
* $Id: io.c 3319 2007-03-29 20:03:06Z jilles $
*/
#include "setup.h"
#include <sys/types.h>
#include <sys/socket.h>
#include <assert.h>
#include <errno.h>
#include <string.h>
#include <stdlib.h>
#include <stdarg.h>
#include <stdio.h>
#include <unistd.h>
#ifdef HAVE_LIBZ
#include <zlib.h>
#endif
#include "servlink.h"
#include "io.h"
#include "control.h"
static int check_error(int, int, int);
static const char *
fd_name(int fd)
{
if(fd == CONTROL.fd)
return "control";
if(fd == LOCAL.fd)
return "data";
if(fd == REMOTE.fd)
return "network";
/* uh oh... */
return "unknown";
}
#if defined( HAVE_LIBZ )
static unsigned char tmp_buf[BUFLEN];
static unsigned char tmp2_buf[BUFLEN];
#endif
static unsigned char ctrl_buf[256] = "";
static unsigned int ctrl_len = 0;
static unsigned int ctrl_ofs = 0;
void
io_loop(int nfds)
{
fd_set rfds;
fd_set wfds;
int i, ret;
/* loop forever */
for (;;)
{
FD_ZERO(&rfds);
FD_ZERO(&wfds);
for (i = 0; i < 3; i++)
{
if(fds[i].read_cb)
FD_SET(fds[i].fd, &rfds);
if(fds[i].write_cb)
FD_SET(fds[i].fd, &wfds);
}
/* we have <3 fds ever, so I don't think select is too painful */
ret = select(nfds, &rfds, &wfds, NULL, NULL);
if(ret < 0)
{
check_error(ret, IO_SELECT, -1); /* exit on fatal errors */
}
else if(ret > 0)
{
/* call any callbacks */
for (i = 2; i >= 0; i--)
{
if(FD_ISSET(fds[i].fd, &rfds) && fds[i].read_cb)
(*fds[i].read_cb) ();
if(FD_ISSET(fds[i].fd, &wfds) && fds[i].write_cb)
(*fds[i].write_cb) ();
}
}
}
}
void
send_data_blocking(int fd, unsigned char *data, int datalen)
{
int ret;
fd_set wfds;
while (1)
{
ret = write(fd, data, datalen);
if(ret == datalen)
return;
else if(ret > 0)
{
data += ret;
datalen -= ret;
}
ret = check_error(ret, IO_WRITE, fd);
FD_ZERO(&wfds);
FD_SET(fd, &wfds);
/* sleep until we can write to the fd */
while (1)
{
ret = select(fd + 1, NULL, &wfds, NULL, NULL);
if(ret > 0) /* break out so we can write */
break;
if(ret < 0) /* error ? */
check_error(ret, IO_SELECT, fd); /* exit on fatal errors */
/* loop on non-fatal errors */
}
}
}
/*
* process_sendq:
*
* used before CMD_INIT to pass contents of SendQ from ircd
* to servlink. This data must _not_ be encrypted/compressed.
*/
void
process_sendq(struct ctrl_command *cmd)
{
send_data_blocking(REMOTE.fd, cmd->data, cmd->datalen);
}
/*
* process_recvq:
*
* used before CMD_INIT to pass contents of RecvQ from ircd
* to servlink. This data must be decrypted/decopmressed before
* sending back to the ircd.
*/
void
process_recvq(struct ctrl_command *cmd)
{
int ret;
unsigned char *buf;
int blen;
unsigned char *data = cmd->data;
unsigned int datalen = cmd->datalen;
buf = data;
blen = datalen;
ret = -1;
if(datalen > READLEN)
send_error("Error processing INJECT_RECVQ - buffer too long (%d > %d)",
datalen, READLEN);
#ifdef HAVE_LIBZ
if(in_state.zip)
{
/* decompress data */
in_state.zip_state.z_stream.next_in = buf;
in_state.zip_state.z_stream.avail_in = blen;
in_state.zip_state.z_stream.next_out = tmp2_buf;
in_state.zip_state.z_stream.avail_out = BUFLEN;
buf = tmp2_buf;
while (in_state.zip_state.z_stream.avail_in)
{
if((ret = inflate(&in_state.zip_state.z_stream, Z_NO_FLUSH)) != Z_OK)
{
if(!strncmp("ERROR ", (char *)in_state.zip_state.z_stream.next_in, 6))
send_error("Received uncompressed ERROR");
else
send_error("Inflate failed: %s", zError(ret));
}
blen = BUFLEN - in_state.zip_state.z_stream.avail_out;
if(in_state.zip_state.z_stream.avail_in)
{
send_data_blocking(LOCAL.fd, buf, blen);
blen = 0;
in_state.zip_state.z_stream.next_out = buf;
in_state.zip_state.z_stream.avail_out = BUFLEN;
}
}
if(!blen)
return;
}
#endif
send_data_blocking(LOCAL.fd, buf, blen);
}
void
send_zipstats(struct ctrl_command *unused)
{
#ifdef HAVE_LIBZ
int i = 0;
int ret;
u_int32_t len;
if(!in_state.active || !out_state.active)
send_error("Error processing CMD_ZIPSTATS - link is not active!");
if(!in_state.zip || !out_state.zip)
send_error("Error processing CMD_ZIPSTATS - link is not compressed!");
ctrl_buf[i++] = RPL_ZIPSTATS;
ctrl_buf[i++] = 0;
ctrl_buf[i++] = 16;
len = (u_int32_t) in_state.zip_state.z_stream.total_out;
ctrl_buf[i++] = ((len >> 24) & 0xFF);
ctrl_buf[i++] = ((len >> 16) & 0xFF);
ctrl_buf[i++] = ((len >> 8) & 0xFF);
ctrl_buf[i++] = ((len) & 0xFF);
len = (u_int32_t) in_state.zip_state.z_stream.total_in;
ctrl_buf[i++] = ((len >> 24) & 0xFF);
ctrl_buf[i++] = ((len >> 16) & 0xFF);
ctrl_buf[i++] = ((len >> 8) & 0xFF);
ctrl_buf[i++] = ((len) & 0xFF);
len = (u_int32_t) out_state.zip_state.z_stream.total_in;
ctrl_buf[i++] = ((len >> 24) & 0xFF);
ctrl_buf[i++] = ((len >> 16) & 0xFF);
ctrl_buf[i++] = ((len >> 8) & 0xFF);
ctrl_buf[i++] = ((len) & 0xFF);
len = (u_int32_t) out_state.zip_state.z_stream.total_out;
ctrl_buf[i++] = ((len >> 24) & 0xFF);
ctrl_buf[i++] = ((len >> 16) & 0xFF);
ctrl_buf[i++] = ((len >> 8) & 0xFF);
ctrl_buf[i++] = ((len) & 0xFF);
in_state.zip_state.z_stream.total_in = 0;
in_state.zip_state.z_stream.total_out = 0;
out_state.zip_state.z_stream.total_in = 0;
out_state.zip_state.z_stream.total_out = 0;
ret = check_error(write(CONTROL.fd, ctrl_buf, i), IO_WRITE, CONTROL.fd);
if(ret < i)
{
/* write incomplete, register write cb */
CONTROL.write_cb = write_ctrl;
/* deregister read_cb */
CONTROL.read_cb = NULL;
ctrl_ofs = ret;
ctrl_len = i - ret;
return;
}
#else
send_error("can't send_zipstats -- no zlib support!");
#endif
}
/* send_error
* - we ran into some problem, make a last ditch effort to
* flush the control fd sendq, then (blocking) send an
* error message over the control fd.
*/
void
send_error(const char *message, ...)
{
va_list args;
static int sending_error = 0;
struct linger linger_opt = { 1, 30 }; /* wait 30 seconds */
int len;
if(sending_error)
exit(1); /* we did _try_ */
sending_error = 1;
if(ctrl_len) /* attempt to flush any data we have... */
{
send_data_blocking(CONTROL.fd, (ctrl_buf + ctrl_ofs), ctrl_len);
}
/* prepare the message, in in_buf, since we won't be using it again.. */
in_state.buf[0] = RPL_ERROR;
in_state.buf[1] = 0;
in_state.buf[2] = 0;
va_start(args, message);
len = vsprintf((char *) in_state.buf + 3, message, args);
va_end(args);
in_state.buf[3 + len++] = '\0';
in_state.buf[1] = len >> 8;
in_state.buf[2] = len & 0xFF;
len += 3;
send_data_blocking(CONTROL.fd, in_state.buf, len);
/* XXX - is this portable?
* this obviously will fail on a non socket.. */
setsockopt(CONTROL.fd, SOL_SOCKET, SO_LINGER, &linger_opt, sizeof(struct linger));
/* well, we've tried... */
exit(1); /* now abort */
}
/* read_ctrl
* called when a command is waiting on the control pipe
*/
void
read_ctrl(void)
{
int ret;
unsigned char tmp[2];
unsigned char *len;
struct command_def *cdef;
static struct ctrl_command cmd = { 0, 0, 0, 0, NULL };
if(cmd.command == 0) /* we don't have a command yet */
{
cmd.gotdatalen = 0;
cmd.datalen = 0;
cmd.readdata = 0;
cmd.data = NULL;
/* read the command */
if(!(ret = check_error(read(CONTROL.fd, tmp, 1), IO_READ, CONTROL.fd)))
return;
cmd.command = tmp[0];
}
for (cdef = command_table; cdef->commandid; cdef++)
{
if((int)cdef->commandid == cmd.command)
break;
}
if(!cdef->commandid)
{
send_error("Unsupported command (servlink/ircd out of sync?): %d", cmd.command);
/* NOTREACHED */
}
/* read datalen for commands including data */
if(cdef->flags & COMMAND_FLAG_DATA)
{
if(cmd.gotdatalen < 2)
{
len = tmp;
if(!(ret = check_error(read(CONTROL.fd, len,
(2 - cmd.gotdatalen)), IO_READ, CONTROL.fd)))
return;
if(cmd.gotdatalen == 0)
{
cmd.datalen = len[0] << 8;
cmd.gotdatalen++;
ret--;
len++;
}
if(ret && (cmd.gotdatalen == 1))
{
cmd.datalen |= len[0];
cmd.gotdatalen++;
if(cmd.datalen > 0)
cmd.data = calloc(cmd.datalen, 1);
}
}
}
if(cmd.readdata < cmd.datalen) /* try to get any remaining data */
{
if(!(ret = check_error(read(CONTROL.fd,
(cmd.data + cmd.readdata),
cmd.datalen - cmd.readdata), IO_READ, CONTROL.fd)))
return;
cmd.readdata += ret;
if(cmd.readdata < cmd.datalen)
return;
}
/* we now have the command and any data */
(*cdef->handler) (&cmd);
if(cmd.datalen > 0)
free(cmd.data);
cmd.command = 0;
}
void
write_ctrl(void)
{
int ret;
assert(ctrl_len);
if(!(ret = check_error(write(CONTROL.fd, (ctrl_buf + ctrl_ofs),
ctrl_len), IO_WRITE, CONTROL.fd)))
return; /* no data waiting */
ctrl_len -= ret;
if(!ctrl_len)
{
/* write completed, de-register write cb */
CONTROL.write_cb = NULL;
/* reregister read_cb */
CONTROL.read_cb = read_ctrl;
ctrl_ofs = 0;
}
else
ctrl_ofs += ret;
}
void
read_data(void)
{
int ret, ret2;
unsigned char *buf = out_state.buf;
int blen;
ret2 = -1;
assert(!out_state.len);
#if defined(HAVE_LIBZ)
if(out_state.zip || out_state.crypt)
buf = tmp_buf;
#endif
while ((ret = check_error(read(LOCAL.fd, buf, READLEN), IO_READ, LOCAL.fd)))
{
blen = ret;
#ifdef HAVE_LIBZ
if(out_state.zip)
{
out_state.zip_state.z_stream.next_in = buf;
out_state.zip_state.z_stream.avail_in = ret;
buf = out_state.buf;
out_state.zip_state.z_stream.next_out = buf;
out_state.zip_state.z_stream.avail_out = BUFLEN;
if(!(ret2 = deflate(&out_state.zip_state.z_stream,
Z_PARTIAL_FLUSH)) == Z_OK)
send_error("error compressing outgoing data - deflate returned: %s",
zError(ret2));
if(!out_state.zip_state.z_stream.avail_out)
send_error("error compressing outgoing data - avail_out == 0");
if(out_state.zip_state.z_stream.avail_in)
send_error("error compressing outgoing data - avail_in != 0");
blen = BUFLEN - out_state.zip_state.z_stream.avail_out;
}
#endif
ret = check_error(write(REMOTE.fd, out_state.buf, blen), IO_WRITE, REMOTE.fd);
if(ret < blen)
{
/* write incomplete, register write cb */
REMOTE.write_cb = write_net;
/* deregister read_cb */
LOCAL.read_cb = NULL;
out_state.ofs = ret;
out_state.len = blen - ret;
return;
}
#if defined(HAVE_LIBZ)
if(out_state.zip)
buf = tmp_buf;
#endif
}
}
void
write_net(void)
{
int ret;
assert(out_state.len);
if(!(ret = check_error(write(REMOTE.fd,
(out_state.buf + out_state.ofs),
out_state.len), IO_WRITE, REMOTE.fd)))
return; /* no data waiting */
out_state.len -= ret;
if(!out_state.len)
{
/* write completed, de-register write cb */
REMOTE.write_cb = NULL;
/* reregister read_cb */
LOCAL.read_cb = read_data;
out_state.ofs = 0;
}
else
out_state.ofs += ret;
}
void
read_net(void)
{
int ret;
int ret2;
unsigned char *buf = in_state.buf;
int blen;
ret2 = -1;
assert(!in_state.len);
#if defined(HAVE_LIBZ)
if(in_state.zip)
buf = tmp_buf;
#endif
while ((ret = check_error(read(REMOTE.fd, buf, READLEN), IO_READ, REMOTE.fd)))
{
blen = ret;
#ifdef HAVE_LIBZ
if(in_state.zip)
{
/* decompress data */
in_state.zip_state.z_stream.next_in = buf;
in_state.zip_state.z_stream.avail_in = ret;
in_state.zip_state.z_stream.next_out = in_state.buf;
in_state.zip_state.z_stream.avail_out = BUFLEN;
while (in_state.zip_state.z_stream.avail_in)
{
if((ret2 = inflate(&in_state.zip_state.z_stream,
Z_NO_FLUSH)) != Z_OK)
{
if(!strncmp("ERROR ", (char *)buf, 6))
send_error("Received uncompressed ERROR");
send_error("Inflate failed: %s", zError(ret2));
}
blen = BUFLEN - in_state.zip_state.z_stream.avail_out;
if(in_state.zip_state.z_stream.avail_in)
{
if(blen)
{
send_data_blocking(LOCAL.fd, in_state.buf, blen);
blen = 0;
}
in_state.zip_state.z_stream.next_out = in_state.buf;
in_state.zip_state.z_stream.avail_out = BUFLEN;
}
}
if(!blen)
return; /* that didn't generate any decompressed input.. */
}
#endif
ret = check_error(write(LOCAL.fd, in_state.buf, blen), IO_WRITE, LOCAL.fd);
if(ret < blen)
{
in_state.ofs = ret;
in_state.len = blen - ret;
/* write incomplete, register write cb */
LOCAL.write_cb = write_data;
/* deregister read_cb */
REMOTE.read_cb = NULL;
return;
}
#if defined(HAVE_LIBZ)
if(in_state.zip)
buf = tmp_buf;
#endif
}
}
void
write_data(void)
{
int ret;
assert(in_state.len);
if(!(ret = check_error(write(LOCAL.fd,
(in_state.buf + in_state.ofs),
in_state.len), IO_WRITE, LOCAL.fd)))
return;
in_state.len -= ret;
if(!in_state.len)
{
/* write completed, de-register write cb */
LOCAL.write_cb = NULL;
/* reregister read_cb */
REMOTE.read_cb = read_net;
in_state.ofs = 0;
}
else
in_state.ofs += ret;
}
int
check_error(int ret, int io, int fd)
{
if(ret > 0) /* no error */
return ret;
if(ret == 0) /* EOF */
{
send_error("%s failed on %s: EOF", IO_TYPE(io), FD_NAME(fd));
exit(1); /* NOTREACHED */
}
/* ret == -1.. */
switch (errno)
{
case EINPROGRESS:
case EWOULDBLOCK:
#if EAGAIN != EWOULDBLOCK
case EAGAIN:
#endif
case EALREADY:
case EINTR:
#ifdef ERESTART
case ERESTART:
#endif
/* non-fatal error, 0 bytes read */
return 0;
}
/* fatal error */
send_error("%s failed on %s: %s", IO_TYPE(io), FD_NAME(fd), strerror(errno));
exit(1); /* NOTREACHED */
}