httpd.h

00001 /**
00002  * @file
00003  * HTTP server
00004  */
00005 
00006 /*
00007  * Copyright (c) 2001-2003 Swedish Institute of Computer Science.
00008  * All rights reserved.
00009  *
00010  * Redistribution and use in source and binary forms, with or without modification,
00011  * are permitted provided that the following conditions are met:
00012  *
00013  * 1. Redistributions of source code must retain the above copyright notice,
00014  *    this list of conditions and the following disclaimer.
00015  * 2. Redistributions in binary form must reproduce the above copyright notice,
00016  *    this list of conditions and the following disclaimer in the documentation
00017  *    and/or other materials provided with the distribution.
00018  * 3. The name of the author may not be used to endorse or promote products
00019  *    derived from this software without specific prior written permission.
00020  *
00021  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
00022  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
00023  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
00024  * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
00025  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
00026  * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
00027  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
00028  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
00029  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
00030  * OF SUCH DAMAGE.
00031  *
00032  * This file is part of the lwIP TCP/IP stack.
00033  *
00034  * Author: Adam Dunkels <adam@sics.se>
00035  *
00036  * This version of the file has been modified by Texas Instruments to offer
00037  * simple server-side-include (SSI) and Common Gateway Interface (CGI)
00038  * capability.
00039  */
00040 
00041 #ifndef LWIP_HDR_APPS_HTTPD_H
00042 #define LWIP_HDR_APPS_HTTPD_H
00043 
00044 #include "httpd_opts.h"
00045 #include "lwip/err.h"
00046 #include "lwip/pbuf.h"
00047 
00048 #ifdef __cplusplus
00049 extern "C" {
00050 #endif
00051 
00052 #if LWIP_HTTPD_CGI
00053 
00054 /**
00055  * @ingroup httpd
00056  * Function pointer for a CGI script handler.
00057  *
00058  * This function is called each time the HTTPD server is asked for a file
00059  * whose name was previously registered as a CGI function using a call to
00060  * http_set_cgi_handlers. The iIndex parameter provides the index of the
00061  * CGI within the cgis array passed to http_set_cgi_handlers. Parameters
00062  * pcParam and pcValue provide access to the parameters provided along with
00063  * the URI. iNumParams provides a count of the entries in the pcParam and
00064  * pcValue arrays. Each entry in the pcParam array contains the name of a
00065  * parameter with the corresponding entry in the pcValue array containing the
00066  * value for that parameter. Note that pcParam may contain multiple elements
00067  * with the same name if, for example, a multi-selection list control is used
00068  * in the form generating the data.
00069  *
00070  * The function should return a pointer to a character string which is the
00071  * path and filename of the response that is to be sent to the connected
00072  * browser, for example "/thanks.htm" or "/response/error.ssi".
00073  *
00074  * The maximum number of parameters that will be passed to this function via
00075  * iNumParams is defined by LWIP_HTTPD_MAX_CGI_PARAMETERS. Any parameters in
00076  * the incoming HTTP request above this number will be discarded.
00077  *
00078  * Requests intended for use by this CGI mechanism must be sent using the GET
00079  * method (which encodes all parameters within the URI rather than in a block
00080  * later in the request). Attempts to use the POST method will result in the
00081  * request being ignored.
00082  *
00083  */
00084 typedef const char *(*tCGIHandler)(int iIndex, int iNumParams, char *pcParam[],
00085                              char *pcValue[]);
00086 
00087 /**
00088  * @ingroup httpd
00089  * Structure defining the base filename (URL) of a CGI and the associated
00090  * function which is to be called when that URL is requested.
00091  */
00092 typedef struct
00093 {
00094     const char *pcCGIName;
00095     tCGIHandler pfnCGIHandler;
00096 } tCGI;
00097 
00098 void http_set_cgi_handlers(const tCGI *pCGIs, int iNumHandlers);
00099 
00100 #endif /* LWIP_HTTPD_CGI */
00101 
00102 #if LWIP_HTTPD_CGI || LWIP_HTTPD_CGI_SSI
00103 
00104 #if LWIP_HTTPD_CGI_SSI
00105 /* we have to prototype this struct here to make it available for the handler */
00106 struct fs_file;
00107 
00108 /** Define this generic CGI handler in your application.
00109  * It is called once for every URI with parameters.
00110  * The parameters can be stored to the object passed as connection_state, which
00111  * is allocated to file->state via fs_state_init() from fs_open() or fs_open_custom().
00112  * Content creation via SSI or complete dynamic files can retrieve the CGI params from there.
00113  */
00114 extern void httpd_cgi_handler(struct fs_file *file, const char* uri, int iNumParams,
00115                               char **pcParam, char **pcValue
00116 #if defined(LWIP_HTTPD_FILE_STATE) && LWIP_HTTPD_FILE_STATE
00117                                      , void *connection_state
00118 #endif /* LWIP_HTTPD_FILE_STATE */
00119                                      );
00120 #endif /* LWIP_HTTPD_CGI_SSI */
00121 
00122 #endif /* LWIP_HTTPD_CGI || LWIP_HTTPD_CGI_SSI */
00123 
00124 #if LWIP_HTTPD_SSI
00125 
00126 /**
00127  * @ingroup httpd
00128  * Function pointer for the SSI tag handler callback.
00129  *
00130  * This function will be called each time the HTTPD server detects a tag of the
00131  * form <!--#name--> in files with extensions mentioned in the g_pcSSIExtensions
00132  * array (currently .shtml, .shtm, .ssi, .xml, .json) where "name" appears as
00133  * one of the tags supplied to http_set_ssi_handler in the tags array.  The
00134  * returned insert string, which will be appended after the the string
00135  * "<!--#name-->" in file sent back to the client, should be written to pointer
00136  * pcInsert. iInsertLen contains the size of the buffer pointed to by
00137  * pcInsert. The iIndex parameter provides the zero-based index of the tag as
00138  * found in the tags array and identifies the tag that is to be processed.
00139  *
00140  * The handler returns the number of characters written to pcInsert excluding
00141  * any terminating NULL or HTTPD_SSI_TAG_UNKNOWN when tag is not recognized.
00142  *
00143  * Note that the behavior of this SSI mechanism is somewhat different from the
00144  * "normal" SSI processing as found in, for example, the Apache web server.  In
00145  * this case, the inserted text is appended following the SSI tag rather than
00146  * replacing the tag entirely.  This allows for an implementation that does not
00147  * require significant additional buffering of output data yet which will still
00148  * offer usable SSI functionality. One downside to this approach is when
00149  * attempting to use SSI within JavaScript.  The SSI tag is structured to
00150  * resemble an HTML comment but this syntax does not constitute a comment
00151  * within JavaScript and, hence, leaving the tag in place will result in
00152  * problems in these cases. In order to avoid these problems, define
00153  * LWIP_HTTPD_SSI_INCLUDE_TAG as zero in your lwip options file, or use JavaScript
00154  * style block comments in the form / * # name * / (without the spaces).
00155  */
00156 typedef u16_t (*tSSIHandler)(
00157 #if LWIP_HTTPD_SSI_RAW
00158                              const char* ssi_tag_name,
00159 #else /* LWIP_HTTPD_SSI_RAW */
00160                              int iIndex,
00161 #endif /* LWIP_HTTPD_SSI_RAW */
00162                              char *pcInsert, int iInsertLen
00163 #if LWIP_HTTPD_SSI_MULTIPART
00164                              , u16_t current_tag_part, u16_t *next_tag_part
00165 #endif /* LWIP_HTTPD_SSI_MULTIPART */
00166 #if defined(LWIP_HTTPD_FILE_STATE) && LWIP_HTTPD_FILE_STATE
00167                              , void *connection_state
00168 #endif /* LWIP_HTTPD_FILE_STATE */
00169                              );
00170 
00171 /** Set the SSI handler function
00172  * (if LWIP_HTTPD_SSI_RAW==1, only the first argument is used)
00173  */
00174 void http_set_ssi_handler(tSSIHandler pfnSSIHandler,
00175                           const char **ppcTags, int iNumTags);
00176 
00177 /** For LWIP_HTTPD_SSI_RAW==1, return this to indicate the tag is unknown.
00178  * In this case, the webserver writes a warning into the page.
00179  * You can also just return 0 to write nothing for unknown tags.
00180  */
00181 #define HTTPD_SSI_TAG_UNKNOWN 0xFFFF
00182 
00183 #endif /* LWIP_HTTPD_SSI */
00184 
00185 #if LWIP_HTTPD_SUPPORT_POST
00186 
00187 /* These functions must be implemented by the application */
00188 
00189 /**
00190  * @ingroup httpd
00191  * Called when a POST request has been received. The application can decide
00192  * whether to accept it or not.
00193  *
00194  * @param connection Unique connection identifier, valid until httpd_post_end
00195  *        is called.
00196  * @param uri The HTTP header URI receiving the POST request.
00197  * @param http_request The raw HTTP request (the first packet, normally).
00198  * @param http_request_len Size of 'http_request'.
00199  * @param content_len Content-Length from HTTP header.
00200  * @param response_uri Filename of response file, to be filled when denying the
00201  *        request
00202  * @param response_uri_len Size of the 'response_uri' buffer.
00203  * @param post_auto_wnd Set this to 0 to let the callback code handle window
00204  *        updates by calling 'httpd_post_data_recved' (to throttle rx speed)
00205  *        default is 1 (httpd handles window updates automatically)
00206  * @return ERR_OK: Accept the POST request, data may be passed in
00207  *         another err_t: Deny the POST request, send back 'bad request'.
00208  */
00209 err_t httpd_post_begin(void *connection, const char *uri, const char *http_request,
00210                        u16_t http_request_len, int content_len, char *response_uri,
00211                        u16_t response_uri_len, u8_t *post_auto_wnd);
00212 
00213 /**
00214  * @ingroup httpd
00215  * Called for each pbuf of data that has been received for a POST.
00216  * ATTENTION: The application is responsible for freeing the pbufs passed in!
00217  *
00218  * @param connection Unique connection identifier.
00219  * @param p Received data.
00220  * @return ERR_OK: Data accepted.
00221  *         another err_t: Data denied, http_post_get_response_uri will be called.
00222  */
00223 err_t httpd_post_receive_data(void *connection, struct pbuf *p);
00224 
00225 /**
00226  * @ingroup httpd
00227  * Called when all data is received or when the connection is closed.
00228  * The application must return the filename/URI of a file to send in response
00229  * to this POST request. If the response_uri buffer is untouched, a 404
00230  * response is returned.
00231  *
00232  * @param connection Unique connection identifier.
00233  * @param response_uri Filename of response file, to be filled when denying the request
00234  * @param response_uri_len Size of the 'response_uri' buffer.
00235  */
00236 void httpd_post_finished(void *connection, char *response_uri, u16_t response_uri_len);
00237 
00238 #if LWIP_HTTPD_POST_MANUAL_WND
00239 void httpd_post_data_recved(void *connection, u16_t recved_len);
00240 #endif /* LWIP_HTTPD_POST_MANUAL_WND */
00241 
00242 #endif /* LWIP_HTTPD_SUPPORT_POST */
00243 
00244 void httpd_init(void);
00245 
00246 #if HTTPD_ENABLE_HTTPS
00247 struct altcp_tls_config;
00248 void httpd_inits(struct altcp_tls_config *conf);
00249 #endif
00250 
00251 #ifdef __cplusplus
00252 }
00253 #endif
00254 
00255 #endif /* LWIP_HDR_APPS_HTTPD_H */