px4-firmware/apps/netutils/thttpd/thttpd.c

862 lines
23 KiB
C

/****************************************************************************
* netutils/thttpd/thttpd.c
* Tiny HTTP Server
*
* Copyright (C) 2009, 2011 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <gnutt@nuttx.org>
*
* Derived from the file of the same name in the original THTTPD package:
*
* Copyright © 1995,1998,1999,2000,2001 by Jef Poskanzer <jef@mail.acme.com>.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <fcntl.h>
#include <signal.h>
#include <errno.h>
#include <debug.h>
#include <nuttx/compiler.h>
#include <nuttx/binfmt/symtab.h>
#include <apps/netutils/thttpd.h>
#include "config.h"
#include "fdwatch.h"
#include "libhttpd.h"
#include "thttpd_alloc.h"
#include "thttpd_strings.h"
#include "timers.h"
#ifdef CONFIG_THTTPD
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
#ifndef MAXPATHLEN
# define MAXPATHLEN 64
#endif
/* The connection states */
#define CNST_FREE 0
#define CNST_READING 1
#define CNST_SENDING 2
#define CNST_LINGERING 3
#define SPARE_FDS 2
#define AVAILABLE_FDS (CONFIG_NSOCKET_DESCRIPTORS - SPARE_FDS)
/****************************************************************************
* Private Types
****************************************************************************/
struct connect_s
{
struct connect_s *next;
int conn_state;
httpd_conn *hc;
time_t active_at;
Timer *wakeup_timer;
Timer *linger_timer;
off_t end_offset; /* The final offset+1 of the file to send */
off_t offset; /* The current offset into the file to send */
bool eof; /* Set true when length==0 read from file */
};
/****************************************************************************
* Private Data
****************************************************************************/
static httpd_server *hs;
static struct connect_s *free_connections;
static struct connect_s *connects;
static struct fdwatch_s *fw;
/****************************************************************************
* Public Data
****************************************************************************/
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
static void shut_down(void);
static int handle_newconnect(struct timeval *tv, int listen_fd);
static void handle_read(struct connect_s *conn, struct timeval *tv);
static void handle_send(struct connect_s *conn, struct timeval *tv);
static void handle_linger(struct connect_s *conn, struct timeval *tv);
static void finish_connection(struct connect_s *conn, struct timeval *tv);
static void clear_connection(struct connect_s *conn, struct timeval *tv);
static void really_clear_connection(struct connect_s *conn);
static void idle(ClientData client_data, struct timeval *nowP);
static void linger_clear_connection(ClientData client_data, struct timeval *nowP);
static void occasional(ClientData client_data, struct timeval *nowP);
/****************************************************************************
* Private Functions
****************************************************************************/
static void shut_down(void)
{
int cnum;
for (cnum = 0; cnum < AVAILABLE_FDS; ++cnum)
{
if (connects[cnum].conn_state != CNST_FREE)
{
httpd_close_conn(connects[cnum].hc);
}
if (connects[cnum].hc != NULL)
{
httpd_destroy_conn(connects[cnum].hc);
httpd_free((void *)connects[cnum].hc);
connects[cnum].hc = NULL;
}
}
if (hs)
{
httpd_server *ths = hs;
hs = NULL;
if (ths->listen_fd != -1)
{
fdwatch_del_fd(fw, ths->listen_fd);
}
httpd_terminate(ths);
}
tmr_destroy();
httpd_free((void *)connects);
}
static int handle_newconnect(struct timeval *tv, int listen_fd)
{
struct connect_s *conn;
ClientData client_data;
/* This loops until the accept() fails, trying to start new connections as
* fast as possible so we don't overrun the listen queue.
*/
nvdbg("New connection(s) on listen_fd %d\n", listen_fd);
for (;;)
{
/* Get the next free connection from the free list */
conn = free_connections;
/* Are there any free connections? */
if (!conn)
{
/* Out of connection slots. Run the timers, then the existing
* connections, and maybe we'll free up a slot by the time we get
* back here.
*/
ndbg("No free connections\n");
tmr_run(tv);
return -1;
}
/* Make the httpd_conn if necessary */
if (!conn->hc)
{
conn->hc = NEW(httpd_conn, 1);
if (conn->hc == NULL)
{
ndbg("out of memory allocating an httpd_conn\n");
exit(1);
}
conn->hc->initialized = 0;
}
/* Get the connection */
switch (httpd_get_conn(hs, listen_fd, conn->hc))
{
/* Some error happened. Run the timers, then the existing
* connections. Maybe the error will clear.
*/
case GC_FAIL:
tmr_run(tv);
return -1;
/* No more connections to accept for now */
case GC_NO_MORE:
return 0;
default:
break;
}
nvdbg("New connection fd %d\n", conn->hc->conn_fd);
/* Remove the connection entry from the free list */
conn->conn_state = CNST_READING;
free_connections = conn->next;
conn->next = NULL;
client_data.p = conn;
conn->active_at = tv->tv_sec;
conn->wakeup_timer = NULL;
conn->linger_timer = NULL;
conn->offset = 0;
/* Set the connection file descriptor to no-delay mode */
httpd_set_ndelay(conn->hc->conn_fd);
fdwatch_add_fd(fw, conn->hc->conn_fd, conn);
}
}
static void handle_read(struct connect_s *conn, struct timeval *tv)
{
ClientData client_data;
httpd_conn *hc = conn->hc;
off_t actual;
int sz;
/* Is there room in our buffer to read more bytes? */
if (hc->read_idx >= hc->read_size)
{
if (hc->read_size > CONFIG_THTTPD_MAXREALLOC)
{
BADREQUEST("MAXREALLOC");
goto errout_with_400;
}
httpd_realloc_str(&hc->read_buf, &hc->read_size, hc->read_size + CONFIG_THTTPD_REALLOCINCR);
}
/* Read some more bytes */
sz = read(hc->conn_fd, &(hc->read_buf[hc->read_idx]), hc->read_size - hc->read_idx);
if (sz == 0)
{
BADREQUEST("EOF");
goto errout_with_400;
}
if (sz < 0)
{
/* Ignore EINTR and EAGAIN. Also ignore EWOULDBLOCK. At first glance
* you would think that connections returned by fdwatch as readable
* should never give an EWOULDBLOCK; however, this apparently can
* happen if a packet gets garbled.
*/
if (errno == EINTR || errno == EAGAIN || errno == EWOULDBLOCK)
{
return;
}
ndbg("read(fd=%d) failed: %d\n", hc->conn_fd, errno);
BADREQUEST("read");
goto errout_with_400;
}
hc->read_idx += sz;
conn->active_at = tv->tv_sec;
/* Do we have a complete request yet? */
switch (httpd_got_request(hc))
{
case GR_NO_REQUEST:
return;
case GR_BAD_REQUEST:
BADREQUEST("httpd_got_request");
goto errout_with_400;
}
/* Yes. Try parsing and resolving it */
if (httpd_parse_request(hc) < 0)
{
goto errout_with_connection;
}
/* Start the connection going */
if (httpd_start_request(hc, tv) < 0)
{
/* Something went wrong. Close down the connection */
goto errout_with_connection;
}
/* Set up the file offsets to read */
conn->eof = false;
if (hc->got_range)
{
conn->offset = hc->range_start;
conn->end_offset = hc->range_end + 1;
}
else
{
conn->offset = 0;
if (hc->bytes_to_send < 0)
{
conn->end_offset = 0;
}
else
{
conn->end_offset = hc->bytes_to_send;
}
}
/* Check if it's already handled */
if (hc->file_fd < 0)
{
/* No file descriptor means someone else is handling it */
conn->offset = hc->bytes_sent;
goto errout_with_connection;
}
if (conn->offset >= conn->end_offset)
{
/* There's nothing to send */
goto errout_with_connection;
}
/* Seek to the offset of the next byte to send */
actual = lseek(hc->file_fd, conn->offset, SEEK_SET);
if (actual != conn->offset)
{
ndbg("fseek to %d failed: offset=%d errno=%d\n", conn->offset, actual, errno);
BADREQUEST("lseek");
goto errout_with_400;
}
/* We have a valid connection and a file to send to it */
conn->conn_state = CNST_SENDING;
client_data.p = conn;
fdwatch_del_fd(fw, hc->conn_fd);
return;
errout_with_400:
BADREQUEST("errout");
httpd_send_err(hc, 400, httpd_err400title, "", httpd_err400form, "");
errout_with_connection:
finish_connection(conn, tv);
return;
}
static inline int read_buffer(struct connect_s *conn)
{
httpd_conn *hc = conn->hc;
ssize_t nread = 0;
if (hc->buflen < CONFIG_THTTPD_IOBUFFERSIZE && !conn->eof)
{
nread = read(hc->file_fd, &hc->buffer[hc->buflen],
CONFIG_THTTPD_IOBUFFERSIZE - hc->buflen);
if (nread == 0)
{
/* Reading zero bytes means we are at the end of file */
conn->end_offset = conn->offset;
conn->eof = true;
}
else if (nread > 0)
{
hc->buflen += nread;
}
}
return nread;
}
static void handle_send(struct connect_s *conn, struct timeval *tv)
{
httpd_conn *hc = conn->hc;
int nwritten;
int nread;
/* Read until the entire file is sent -- this could take awhile!! */
while (conn->offset < conn->end_offset)
{
nvdbg("offset: %d end_offset: %d bytes_sent: %d\n",
conn->offset, conn->end_offset, conn->hc->bytes_sent);
/* Fill the rest of the response buffer with file data */
nread = read_buffer(conn);
if (nread < 0)
{
ndbg("File read error: %d\n", errno);
goto errout_clear_connection;
}
nvdbg("Read %d bytes, buflen %d\n", nread, hc->buflen);
/* Send the buffer */
if (hc->buflen > 0)
{
/* httpd_write does not return until all bytes have been sent
* (or an error occurs).
*/
nwritten = httpd_write(hc->conn_fd, hc->buffer, hc->buflen);
if (nwritten < 0)
{
ndbg("Error sending %s: %d\n", hc->encodedurl, errno);
goto errout_clear_connection;
}
/* We wrote one full buffer of data (httpd_write does not
* return until the full buffer is written (or an error occurs).
*/
conn->active_at = tv->tv_sec;
hc->buflen = 0;
/* And update how much of the file we wrote */
conn->offset += nwritten;
conn->hc->bytes_sent += nwritten;
nvdbg("Wrote %d bytes\n", nwritten);
}
}
/* The file transfer is complete -- finish the connection */
nvdbg("Finish connection\n");
finish_connection(conn, tv);
return;
errout_clear_connection:
ndbg("Clear connection\n");
clear_connection(conn, tv);
return;
}
static void handle_linger(struct connect_s *conn, struct timeval *tv)
{
httpd_conn *hc = conn->hc;
int ret;
/* In lingering-close mode we just read and ignore bytes. An error or EOF
* ends things, otherwise we go until a timeout
*/
ret = read(conn->hc->conn_fd, hc->buffer, CONFIG_THTTPD_IOBUFFERSIZE);
if (ret < 0 && (errno == EINTR || errno == EAGAIN))
{
return;
}
if (ret <= 0)
{
really_clear_connection(conn);
}
}
static void finish_connection(struct connect_s *conn, struct timeval *tv)
{
/* If we haven't actually sent the buffered response yet, do so now */
httpd_write_response(conn->hc);
/* And clear */
clear_connection(conn, tv);
}
static void clear_connection(struct connect_s *conn, struct timeval *tv)
{
ClientData client_data;
if (conn->wakeup_timer != NULL)
{
tmr_cancel(conn->wakeup_timer);
conn->wakeup_timer = 0;
}
/* This is our version of Apache's lingering_close() routine, which is
* their version of the often-broken SO_LINGER socket option. For why
* this is necessary, see http://www.apache.org/docs/misc/fin_wait_2.html
* What we do is delay the actual closing for a few seconds, while reading
* any bytes that come over the connection. However, we don't want to do
* this unless it's necessary, because it ties up a connection slot and
* file descriptor which means our maximum connection-handling rateis
* lower. So, elsewhere we set a flag when we detect the few
* circumstances that make a lingering close necessary. If the flag isn't
* set we do the real close now.
*/
if (conn->conn_state == CNST_LINGERING)
{
/* If we were already lingering, shut down for real */
tmr_cancel(conn->linger_timer);
conn->linger_timer = NULL;
conn->hc->should_linger = false;
}
else if (conn->hc->should_linger)
{
fdwatch_del_fd(fw, conn->hc->conn_fd);
conn->conn_state = CNST_LINGERING;
fdwatch_add_fd(fw, conn->hc->conn_fd, conn);
client_data.p = conn;
conn->linger_timer = tmr_create(tv, linger_clear_connection, client_data,
CONFIG_THTTPD_LINGER_MSEC, 0);
if (conn->linger_timer != NULL)
{
return;
}
ndbg("tmr_create(linger_clear_connection) failed\n");
}
/* Either we are done lingering, we shouldn't linger, or we failed to setup the linger */
really_clear_connection(conn);
}
static void really_clear_connection(struct connect_s *conn)
{
fdwatch_del_fd(fw, conn->hc->conn_fd);
httpd_close_conn(conn->hc);
if (conn->linger_timer != NULL)
{
tmr_cancel(conn->linger_timer);
conn->linger_timer = 0;
}
/* Put the connection structure back on the free list */
conn->conn_state = CNST_FREE;
conn->next = free_connections;
free_connections = conn;
}
static void idle(ClientData client_data, struct timeval *nowP)
{
int cnum;
struct connect_s *conn;
for (cnum = 0; cnum < AVAILABLE_FDS; ++cnum)
{
conn = &connects[cnum];
switch (conn->conn_state)
{
case CNST_READING:
if (nowP->tv_sec - conn->active_at >= CONFIG_THTTPD_IDLE_READ_LIMIT_SEC)
{
ndbg("%s connection timed out reading\n", httpd_ntoa(&conn->hc->client_addr));
httpd_send_err(conn->hc, 408, httpd_err408title, "",
httpd_err408form, "");
finish_connection(conn, nowP);
}
break;
case CNST_SENDING:
if (nowP->tv_sec - conn->active_at >= CONFIG_THTTPD_IDLE_SEND_LIMIT_SEC)
{
ndbg("%s connection timed out sending\n", httpd_ntoa(&conn->hc->client_addr));
clear_connection(conn, nowP);
}
break;
}
}
}
static void linger_clear_connection(ClientData client_data, struct timeval *nowP)
{
struct connect_s *conn;
nvdbg("Clear connection\n");
conn = (struct connect_s *) client_data.p;
conn->linger_timer = NULL;
really_clear_connection(conn);
}
static void occasional(ClientData client_data, struct timeval *nowP)
{
tmr_cleanup();
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Function: thttpd_main
*
* Description:
* This function is the entrypoint into the THTTPD server. It does not
* return. It may be called, the normal mechanism for starting the server
* is:
*
* 1) Set is g_thttpdsymtab and g_thttpdnsymbols. The user is required
* to provide a symbol table to use for binding CGI programs (if CGI
* is enabled. See examples/nxflat and examples/thttpd for examples of
* how such a symbol table may be created.
* 2) Call task_create() to start thttpd_main()
*
****************************************************************************/
int thttpd_main(int argc, char **argv)
{
int num_ready;
int cnum;
FAR struct connect_s *conn;
FAR httpd_conn *hc;
httpd_sockaddr sa;
struct timeval tv;
#ifdef CONFIG_THTTPD_DIR
int ret;
#endif
nvdbg("THTTPD started\n");
/* Setup host address */
#ifdef CONFIG_NET_IPv6
# error "IPv6 support not yet implemented"
#else
sa.sin_family = AF_INET;
sa.sin_port = HTONS(CONFIG_THTTPD_PORT);
sa.sin_addr.s_addr = HTONL(CONFIG_THTTPD_IPADDR);
#endif
/* Initialize the fdwatch package to handle all of the configured
* socket descriptors
*/
fw = fdwatch_initialize(CONFIG_NSOCKET_DESCRIPTORS);
if (!fw)
{
ndbg("fdwatch initialization failure\n");
exit(1);
}
/* Switch directories again if requested */
#ifdef CONFIG_THTTPD_DATADIR
if (chdir(CONFIG_THTTPD_DATADIR) < 0)
{
ndbg("chdir to %s: %d\n", CONFIG_THTTPD_DATADIR, errno);
exit(1);
}
#endif
/* Initialize the timer package */
tmr_init();
/* Initialize the HTTP layer */
nvdbg("Calling httpd_initialize()\n");
hs = httpd_initialize(&sa);
if (!hs)
{
ndbg("httpd_initialize() failed\n");
exit(1);
}
/* Set up the occasional timer */
if (tmr_create(NULL, occasional, JunkClientData, CONFIG_THTTPD_OCCASIONAL_MSEC * 1000L, 1) == NULL)
{
ndbg("tmr_create(occasional) failed\n");
exit(1);
}
/* Set up the idle timer */
if (tmr_create(NULL, idle, JunkClientData, 5 * 1000L, 1) == NULL)
{
ndbg("tmr_create(idle) failed\n");
exit(1);
}
/* Initialize our connections table */
connects = NEW(struct connect_s, AVAILABLE_FDS);
if (connects == NULL)
{
ndbg("Out of memory allocating a struct connect_s\n");
exit(1);
}
for (cnum = 0; cnum < AVAILABLE_FDS; ++cnum)
{
connects[cnum].conn_state = CNST_FREE;
connects[cnum].next = &connects[cnum + 1];
connects[cnum].hc = NULL;
}
connects[AVAILABLE_FDS-1].next = NULL; /* End of link list */
free_connections = connects; /* Beginning of the link list */
if (hs != NULL)
{
if (hs->listen_fd != -1)
{
fdwatch_add_fd(fw, hs->listen_fd, NULL);
}
}
/* Main loop */
nvdbg("Entering the main loop\n");
(void)gettimeofday(&tv, NULL);
for(;;)
{
/* Do the fd watch */
num_ready = fdwatch(fw, tmr_mstimeout(&tv));
if (num_ready < 0)
{
if (errno == EINTR || errno == EAGAIN)
{
/* Not errors... try again */
continue;
}
ndbg("fdwatch failed: %d\n", errno);
exit(1);
}
(void)gettimeofday(&tv, NULL);
if (num_ready == 0)
{
/* No fd's are ready - run the timers */
tmr_run(&tv);
continue;
}
/* Is it a new connection? */
if (fdwatch_check_fd(fw, hs->listen_fd))
{
if (!handle_newconnect(&tv, hs->listen_fd))
{
/* Go around the loop and do another fdwatch, rather than
* dropping through and processing existing connections. New
* connections always get priority.
*/
continue;
}
}
/* Find the connections that need servicing */
while ((conn = (struct connect_s*)fdwatch_get_next_client_data(fw)) != (struct connect_s*)-1)
{
if (conn)
{
hc = conn->hc;
if (fdwatch_check_fd(fw, hc->conn_fd))
{
nvdbg("Handle conn_state %d\n", conn->conn_state);
switch (conn->conn_state)
{
case CNST_READING:
{
handle_read(conn, &tv);
/* If a GET request was received and a file is ready to
* be sent, then fall through to send the file.
*/
if (conn->conn_state != CNST_SENDING)
{
break;
}
}
case CNST_SENDING:
{
/* Send a file -- this really should be performed on a
* separate thread to keep the serve from locking up during
* the write.
*/
handle_send(conn, &tv);
}
break;
case CNST_LINGERING:
{
/* Linger close the connection */
handle_linger(conn, &tv);
}
break;
}
}
}
}
tmr_run(&tv);
}
/* The main loop terminated */
shut_down();
ndbg("Exiting\n");
exit(0);
}
#endif /* CONFIG_THTTPD */