/****************************************************************************
* netutils/webclient/webclient.c
* Implementation of the HTTP client.
*
* Copyright (C) 2007, 2009 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
*
* Based on uIP which also has a BSD style license:
*
* Author: Adam Dunkels <adam@dunkels.com>
* Copyright (c) 2002, Adam Dunkels.
* 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.
* 3. The name of the author may not be used to endorse or promote
* products derived from this software without specific prior
* written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 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.
*
****************************************************************************/
/* This example shows a HTTP client that is able to download web pages
* and files from web servers. It requires a number of callback
* functions to be implemented by the module that utilizes the code:
* webclient_datahandler().
*/
/****************************************************************************
* Included Files
****************************************************************************/
#ifndef CONFIG_WEBCLIENT_HOST
# include <nuttx/config.h>
# include <nuttx/compiler.h>
# include <debug.h>
#endif
#include <sys/socket.h>
#include <stdint.h>
#include <stdbool.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#ifdef CONFIG_HAVE_GETHOSTBYNAME
# include <netdb.h>
#else
# include <net/uip/resolv.h>
#endif
#include <arpa/inet.h>
#include <netinet/in.h>
#include <net/uip/uip-lib.h>
#include <net/uip/webclient.h>
/****************************************************************************
* Definitions
****************************************************************************/
#define WEBCLIENT_TIMEOUT 100
#define WEBCLIENT_STATE_STATUSLINE 0
#define WEBCLIENT_STATE_HEADERS 1
#define WEBCLIENT_STATE_DATA 2
#define WEBCLIENT_STATE_CLOSE 3
#define HTTPSTATUS_NONE 0
#define HTTPSTATUS_OK 1
#define HTTPSTATUS_MOVED 2
#define HTTPSTATUS_ERROR 3
#define ISO_nl 0x0a
#define ISO_cr 0x0d
#define ISO_space 0x20
/****************************************************************************
* Private Types
****************************************************************************/
struct wget_s
{
/* Internal status */
uint8_t state;
uint8_t httpstatus;
uint16_t port; /* The port number to use in the connection */
/* These describe the just-received buffer of data */
FAR char *buffer; /* user-provided buffer */
int buflen; /* Length of the user provided buffer */
int offset; /* Offset to the beginning of interesting data */
int datend; /* Offset+1 to the last valid byte of data in the buffer */
/* Buffer HTTP header data and parse line at a time */
char line[CONFIG_WEBCLIENT_MAXHTTPLINE];
int ndx;
#ifdef CONFIG_WEBCLIENT_GETMIMETYPE
char mimetype[CONFIG_WEBCLIENT_MAXMIMESIZE];
#endif
char hostname[CONFIG_WEBCLIENT_MAXHOSTNAME];
char filename[CONFIG_WEBCLIENT_MAXFILENAME];
};
/****************************************************************************
* Private Data
****************************************************************************/
static const char g_http10[] = "HTTP/1.0";
static const char g_http11[] = "HTTP/1.1";
#ifdef CONFIG_WEBCLIENT_GETMIMETYPE
static const char g_httpcontenttype[] = "content-type: ";
#endif
static const char g_httphost[] = "host: ";
static const char g_httplocation[] = "location: ";
static const char g_httpget[] = "GET ";
static const char g_httpuseragentfields[] =
"Connection: close\r\n"
"User-Agent: NuttX/0.4.x (; http://www.nuttx.org/)\r\n\r\n";
static const char g_http200[] = "200 ";
static const char g_http301[] = "301 ";
static const char g_http302[] = "302 ";
static const char g_httpcrnl[] = "\r\n";
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: wget_strcpy
****************************************************************************/
static char *wget_strcpy(char *dest, const char *src)
{
int len = strlen(src);
memcpy(dest, src, len);
dest[len] = '\0';
return dest + len;
}
/****************************************************************************
* Name: wget_resolvehost
****************************************************************************/
static inline int wget_resolvehost(const char *hostname, in_addr_t *ipaddr)
{
#ifdef CONFIG_HAVE_GETHOSTBYNAME
struct hostent *he;
nvdbg("Getting address of %s\n", hostname);
he = gethostbyname(hostname);
if (!he)
{
ndbg("gethostbyname failed: %d\n", h_errno);
return ERROR;
}
nvdbg("Using IP address %04x%04x\n", (uint16_t)he->h_addr[1], (uint16_t)he->h_addr[0]);
memcpy(ipaddr, he->h_addr, sizeof(in_addr_t));
return OK;
#else
# ifdef CONFIG_NET_IPv6
struct sockaddr_in6 addr;
# else
struct sockaddr_in addr;
# endif
/* First check if the host is an IP address. */
if (!uiplib_ipaddrconv(hostname, (uint8_t*)ipaddr))
{
/* 'host' does not point to a valid address string. Try to resolve
* the host name to an IP address.
*/
if (resolv_query(hostname, &addr) < 0)
{
/* Needs to set the errno here */
return ERROR;
}
/* Save the host address -- Needs fixed for IPv6 */
*ipaddr = addr.sin_addr.s_addr;
}
return OK;
#endif
}
/****************************************************************************
* Name: wget_parsestatus
****************************************************************************/
static inline int wget_parsestatus(struct wget_s *ws)
{
int offset;
int ndx;
char *dest;
offset = ws->offset;
ndx = ws->ndx;
while (offset < ws->datend)
{
ws->line[ndx] = ws->buffer[offset];
if (ws->line[ndx] == ISO_nl)
{
ws->line[ndx] = '\0';
if ((strncmp(ws->line, g_http10, strlen(g_http10)) == 0) ||
(strncmp(ws->line, g_http11, strlen(g_http11)) == 0))
{
dest = &(ws->line[9]);
ws->httpstatus = HTTPSTATUS_NONE;
/* Check for 200 OK */
if (strncmp(dest, g_http200, strlen(g_http200)) == 0)
{
ws->httpstatus = HTTPSTATUS_OK;
}
/* Check for 301 Moved permanently or 302 Found. Location: header line
* will contain the new location.
*/
else if (strncmp(dest, g_http301, strlen(g_http301)) == 0 ||
strncmp(dest, g_http302, strlen(g_http302)) == 0)
{
ws->httpstatus = HTTPSTATUS_MOVED;
}
}
else
{
return - ECONNABORTED;
}
/* We're done parsing the status line, so start parsing the HTTP headers. */
ws->state = WEBCLIENT_STATE_HEADERS;
break;
}
else
{
offset++;
ndx++;
}
}
ws->offset = offset;
ws->ndx = ndx;
return OK;
}
/****************************************************************************
* Name: wget_parsestatus
****************************************************************************/
static inline int wget_parseheaders(struct wget_s *ws)
{
int offset;
int ndx;
offset = ws->offset;
ndx = ws->ndx;
while (offset < ws->datend)
{
ws->line[ndx] = ws->buffer[offset];
if (ws->line[ndx] == ISO_nl)
{
/* We have an entire HTTP header line in s.line, so
* we parse it.
*/
if (ndx > 0) /* Should always be true */
{
if (ws->line[0] == ISO_cr)
{
/* This was the last header line (i.e., and empty "\r\n"), so
* we are done with the headers and proceed with the actual
* data.
*/
ws->state = WEBCLIENT_STATE_DATA;
goto exit;
}
/* Truncate the trailing \r\n */
ws->line[ndx-1] = '\0';
/* Check for specific HTTP header fields. */
#ifdef CONFIG_WEBCLIENT_GETMIMETYPE
if (strncasecmp(ws->line, g_httpcontenttype, strlen(g_httpcontenttype)) == 0)
{
/* Found Content-type field. */
char *dest = strchr(ws->line, ';');
if (dest != NULL)
{
*dest = 0;
}
strncpy(ws->mimetype, ws->line + strlen(g_httpcontenttype), sizeof(ws->mimetype));
}
else
#endif
if (strncasecmp(ws->line, g_httplocation, strlen(g_httplocation)) == 0)
{
/* Parse the new HTTP host and filename from the URL. Note that
* the return value is ignored. In the event of failure, we
* retain the current location.
*/
(void)uip_parsehttpurl(ws->line + strlen(g_httplocation), &ws->port,
ws->hostname, CONFIG_WEBCLIENT_MAXHOSTNAME,
ws->filename, CONFIG_WEBCLIENT_MAXFILENAME);
nvdbg("New hostname='%s' filename='%s'\n", ws->hostname, ws->filename);
}
}
/* We're done parsing this line, so we reset the index to the start
* of the next line.
*/
ndx = 0;
}
else
{
ndx++;
}
offset++;
}
exit:
ws->offset = offset;
ws->ndx = ndx;
return OK;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: wget
*
* Description:
* Obtain the requested file from an HTTP server using the GET method.
*
* Note: If the function is passed a host name, it must already be in
* the resolver cache in order for the function to connect to the web
* server. It is therefore up to the calling module to implement the
* resolver calls and the signal handler used for reporting a resolv
* query answer.
*
* Input Parameters
* url - A pointer to a string containing either the full URL to
* the file to get (e.g., http://www.nutt.org/index.html, or
* http://192.168.23.1:80/index.html).
* buffer - A user provided buffer to receive the file data (also
* used for the outgoing GET request
* buflen - The size of the user provided buffer
* callback - As data is obtained from the host, this function is
* to dispose of each block of file data as it is received.
*
* Returned Value:
* 0: if the GET operation completed successfully;
* -1: On a failure with errno set appropriately
*
****************************************************************************/
int wget(FAR const char *url, FAR char *buffer, int buflen,
wget_callback_t callback, FAR void *arg)
{
struct sockaddr_in server;
struct wget_s ws;
bool redirected;
char *dest;
int sockfd;
int len;
int ret = OK;
/* Initialize the state structure */
memset(&ws, 0, sizeof(struct wget_s));
ws.buffer = buffer;
ws.buflen = buflen;
ws.port = 80;
/* Parse the hostname (with optional port number) and filename from the URL */
ret = uip_parsehttpurl(url, &ws.port,
ws.hostname, CONFIG_WEBCLIENT_MAXHOSTNAME,
ws.filename, CONFIG_WEBCLIENT_MAXFILENAME);
if (ret != 0)
{
ndbg("Malformed HTTP URL: %s\n", url);
errno = -ret;
return ERROR;
}
nvdbg("hostname='%s' filename='%s'\n", ws.hostname, ws.filename);
/* The following sequence may repeat indefinitely if we are redirected */
do
{
/* Re-initialize portions of the state structure that could have
* been left from the previous time through the loop and should not
* persist with the new connection.
*/
ws.httpstatus = HTTPSTATUS_NONE;
ws.offset = 0;
ws.datend = 0;
ws.ndx = 0;
/* Create a socket */
sockfd = socket(AF_INET, SOCK_STREAM, 0);
if (sockfd < 0)
{
/* socket failed. It will set the errno appropriately */
ndbg("socket failed: %d\n", errno);
return ERROR;
}
/* Get the server adddress from the host name */
server.sin_family = AF_INET;
server.sin_port = htons(ws.port);
ret = wget_resolvehost(ws.hostname, &server.sin_addr.s_addr);
if (ret < 0)
{
/* Could not resolve host (or malformed IP address) */
ndbg("Failed to resolve hostname\n");
ret = -EHOSTUNREACH;
goto errout_with_errno;
}
/* Connect to server. First we have to set some fields in the
* 'server' address structure. The system will assign me an arbitrary
* local port that is not in use.
*/
ret = connect(sockfd, (struct sockaddr *)&server, sizeof(struct sockaddr_in));
if (ret < 0)
{
ndbg("connect failed: %d\n", errno);
goto errout;
}
/* Send the GET request */
dest = ws.buffer;
dest = wget_strcpy(dest, g_httpget);
dest = wget_strcpy(dest, ws.filename);
*dest++ = ISO_space;
dest = wget_strcpy(dest, g_http10);
dest = wget_strcpy(dest, g_httpcrnl);
dest = wget_strcpy(dest, g_httphost);
dest = wget_strcpy(dest, ws.hostname);
dest = wget_strcpy(dest, g_httpcrnl);
dest = wget_strcpy(dest, g_httpuseragentfields);
len = dest - buffer;
ret = send(sockfd, buffer, len, 0);
if (ret < 0)
{
ndbg("send failed: %d\n", errno);
goto errout;
}
/* Now loop to get the file sent in response to the GET. This
* loop continues until either we read the end of file (nbytes == 0)
* or until we detect that we have been redirected.
*/
ws.state = WEBCLIENT_STATE_STATUSLINE;
redirected = false;
for(;;)
{
ws.datend = recv(sockfd, ws.buffer, ws.buflen, 0);
if (ws.datend < 0)
{
ndbg("recv failed: %d\n", errno);
ret = ws.datend;
goto errout_with_errno;
}
else if (ret == 0)
{
close(sockfd);
break;
}
/* Handle initial parsing of the status line */
ws.offset = 0;
if (ws.state == WEBCLIENT_STATE_STATUSLINE)
{
ret = wget_parsestatus(&ws);
if (ret < 0)
{
goto errout_with_errno;
}
}
/* Parse the HTTP data */
if (ws.state == WEBCLIENT_STATE_HEADERS)
{
ret = wget_parseheaders(&ws);
if (ret < 0)
{
goto errout_with_errno;
}
}
/* Dispose of the data payload */
if (ws.state == WEBCLIENT_STATE_DATA)
{
if (ws.httpstatus != HTTPSTATUS_MOVED)
{
/* Let the client decide what to do with the received file */
callback(&ws.buffer, ws.offset, ws.datend, &buflen, arg);
}
else
{
redirected = true;
close(sockfd);
break;
}
}
}
}
while (redirected);
return OK;
errout_with_errno:
errno = -ret;
errout:
close(sockfd);
return ERROR;
}
