/* * Copyright (c) 2001-2003 Swedish Institute of Computer Science. * 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 file is part of the lwIP TCP/IP stack. * * Author: Adam Dunkels * */ /* This httpd supports for a * rudimentary server-side-include facility which will replace tags of the form * in any file whose extension is .shtml, .shtm or .ssi with * strings provided by an include handler whose pointer is provided to the * module via function http_set_ssi_handler(). * Additionally, a simple common * gateway interface (CGI) handling mechanism has been added to allow clients * to hook functions to particular request URIs. * * To enable SSI support, define label LWIP_HTTPD_SSI in lwipopts.h. * To enable CGI support, define label LWIP_HTTPD_CGI in lwipopts.h. * * By default, the server assumes that HTTP headers are already present in * each file stored in the file system. By defining LWIP_HTTPD_DYNAMIC_HEADERS in * lwipopts.h, this behavior can be changed such that the server inserts the * headers automatically based on the extension of the file being served. If * this mode is used, be careful to ensure that the file system image used * does not already contain the header information. * * File system images without headers can be created using the makefsfile * tool with the -h command line option. * * * Notes about valid SSI tags * -------------------------- * * The following assumptions are made about tags used in SSI markers: * * 1. No tag may contain '-' or whitespace characters within the tag name. * 2. Whitespace is allowed between the tag leadin "". * 3. The maximum tag name length is LWIP_HTTPD_MAX_TAG_NAME_LEN, currently 8 characters. * * Notes on CGI usage * ------------------ * * The simple CGI support offered here works with GET method requests only * and can handle up to 16 parameters encoded into the URI. The handler * function may not write directly to the HTTP output but must return a * filename that the HTTP server will send to the browser as a response to * the incoming CGI request. * * @todo: * - don't use mem_malloc() (for SSI/dynamic headers) * - split too long functions into multiple smaller functions? * - support more file types? */ #include "lwip/debug.h" #include "lwip/stats.h" #include "httpd.h" #include "httpd_structs.h" #include "lwip/tcp.h" #include "fs.h" #include #include #if LWIP_TCP #ifndef HTTPD_DEBUG #define HTTPD_DEBUG LWIP_DBG_OFF #endif /** Set this to 1 and add the next line to lwippools.h to use a memp pool * for allocating struct http_state instead of the heap: * * LWIP_MEMPOOL(HTTPD_STATE, 20, 100, "HTTPD_STATE") */ #ifndef HTTPD_USE_MEM_POOL #define HTTPD_USE_MEM_POOL 0 #endif /** The server port for HTTPD to use */ #ifndef HTTPD_SERVER_PORT #define HTTPD_SERVER_PORT 80 #endif /** Maximum retries before the connection is aborted/closed. * - number of times pcb->poll is called -> default is 4*500ms = 2s; * - reset when pcb->sent is called */ #ifndef HTTPD_MAX_RETRIES #define HTTPD_MAX_RETRIES 4 #endif /** The poll delay is X*500ms */ #ifndef HTTPD_POLL_INTERVAL #define HTTPD_POLL_INTERVAL 4 #endif /** Priority for tcp pcbs created by HTTPD (very low by default). * Lower priorities get killed first when running out of memroy. */ #ifndef HTTPD_TCP_PRIO #define HTTPD_TCP_PRIO TCP_PRIO_MIN #endif /** Set this to 1 to enabled timing each file sent */ #ifndef LWIP_HTTPD_TIMING #define LWIP_HTTPD_TIMING 0 #endif #ifndef HTTPD_DEBUG_TIMING #define HTTPD_DEBUG_TIMING LWIP_DBG_OFF #endif /** Set this to 1 on platforms where strnstr is not available */ #ifndef LWIP_HTTPD_STRNSTR_PRIVATE #define LWIP_HTTPD_STRNSTR_PRIVATE 1 #endif /** Set this to one to show error pages when parsing a request fails instead of simply closing the connection. */ #ifndef LWIP_HTTPD_SUPPORT_EXTSTATUS #define LWIP_HTTPD_SUPPORT_EXTSTATUS 0 #endif /** Set this to 0 to drop support for HTTP/0.9 clients (to save some bytes) */ #ifndef LWIP_HTTPD_SUPPORT_V09 #define LWIP_HTTPD_SUPPORT_V09 1 #endif /** Set this to 1 to support HTTP request coming in in multiple packets/pbufs */ #ifndef LWIP_HTTPD_SUPPORT_REQUESTLIST #define LWIP_HTTPD_SUPPORT_REQUESTLIST 0 #endif #if LWIP_HTTPD_SUPPORT_REQUESTLIST /** Number of rx pbufs to enqueue to parse an incoming request (up to the first newline) */ #ifndef LWIP_HTTPD_REQ_QUEUELEN #define LWIP_HTTPD_REQ_QUEUELEN 10 #endif /** Number of (TCP payload-) bytes (in pbufs) to enqueue to parse and incoming request (up to the first double-newline) */ #ifndef LWIP_HTTPD_REQ_BUFSIZE #define LWIP_HTTPD_REQ_BUFSIZE LWIP_HTTPD_MAX_REQ_LENGTH #endif /** Defines the maximum length of a HTTP request line (up to the first CRLF, copied from pbuf into this a global buffer when pbuf- or packet-queues are received - otherwise the input pbuf is used directly) */ #ifndef LWIP_HTTPD_MAX_REQ_LENGTH #define LWIP_HTTPD_MAX_REQ_LENGTH 1023 #endif #endif /* LWIP_HTTPD_SUPPORT_REQUESTLIST */ /** Maximum length of the filename to send as response to a POST request, * filled in by the application when a POST is finished. */ #ifndef LWIP_HTTPD_POST_MAX_RESPONSE_URI_LEN #define LWIP_HTTPD_POST_MAX_RESPONSE_URI_LEN 63 #endif #ifndef true #define true ((u8_t)1) #endif #ifndef false #define false ((u8_t)0) #endif /** Minimum length for a valid HTTP/0.9 request: "GET /\r\n" -> 7 bytes */ #define MIN_REQ_LEN 7 #define CRLF "\r\n" /** This checks whether tcp_write has to copy data or not */ #ifndef HTTP_IS_DATA_VOLATILE /** This was TI's check whether to let TCP copy data or not #define HTTP_IS_DATA_VOLATILE(hs) ((hs->file < (char *)0x20000000) ? 0 : TCP_WRITE_FLAG_COPY)*/ #if LWIP_HTTPD_SSI #define HTTP_IS_DATA_VOLATILE(hs) TCP_WRITE_FLAG_COPY #else /* LWIP_HTTPD_SSI */ /** Default: don't copy if the data is sent from file-system directly */ #define HTTP_IS_DATA_VOLATILE(hs) (((hs->file != NULL) && (hs->handle != NULL) && (hs->file == \ (char*)hs->handle->data + hs->handle->len - hs->left)) \ ? 0 : TCP_WRITE_FLAG_COPY) #endif /* LWIP_HTTPD_SSI */ #endif typedef struct { const char *name; u8_t shtml; } default_filename; const default_filename g_psDefaultFilenames[] = { {"/index.shtml", true }, {"/index.ssi", true }, {"/index.shtm", true }, {"/index.html", false }, {"/index.htm", false } }; #define NUM_DEFAULT_FILENAMES (sizeof(g_psDefaultFilenames) / \ sizeof(default_filename)) #if LWIP_HTTPD_SUPPORT_REQUESTLIST /** HTTP request is copied here from pbufs for simple parsing */ static char httpd_req_buf[LWIP_HTTPD_MAX_REQ_LENGTH+1]; #endif /* LWIP_HTTPD_SUPPORT_REQUESTLIST */ #if LWIP_HTTPD_SUPPORT_POST /** Filename for response file to send when POST is finished */ static char http_post_response_filename[LWIP_HTTPD_POST_MAX_RESPONSE_URI_LEN+1]; #endif /* LWIP_HTTPD_SUPPORT_POST */ #if LWIP_HTTPD_DYNAMIC_HEADERS /* The number of individual strings that comprise the headers sent before each * requested file. */ #define NUM_FILE_HDR_STRINGS 3 #endif /* LWIP_HTTPD_DYNAMIC_HEADERS */ #if LWIP_HTTPD_SSI const char *g_pcSSIExtensions[] = { ".shtml", ".shtm", ".ssi", ".xml" }; #define NUM_SHTML_EXTENSIONS (sizeof(g_pcSSIExtensions) / sizeof(const char *)) enum tag_check_state { TAG_NONE, /* Not processing an SSI tag */ TAG_LEADIN, /* Tag lead in "" being processed */ TAG_SENDING /* Sending tag replacement string */ }; #endif /* LWIP_HTTPD_SSI */ struct http_state { struct fs_file *handle; char *file; /* Pointer to first unsent byte in buf. */ #if LWIP_HTTPD_SUPPORT_REQUESTLIST struct pbuf *req; #endif /* LWIP_HTTPD_SUPPORT_REQUESTLIST */ #if LWIP_HTTPD_SSI || LWIP_HTTPD_DYNAMIC_HEADERS char *buf; /* File read buffer. */ int buf_len; /* Size of file read buffer, buf. */ #endif /* LWIP_HTTPD_SSI || LWIP_HTTPD_DYNAMIC_HEADERS */ u32_t left; /* Number of unsent bytes in buf. */ u8_t retries; #if LWIP_HTTPD_SSI const char *parsed; /* Pointer to the first unparsed byte in buf. */ const char *tag_end; /* Pointer to char after the closing '>' of the tag. */ u32_t parse_left; /* Number of unparsed bytes in buf. */ u8_t tag_check; /* true if we are processing a .shtml file else false */ u16_t tag_index; /* Counter used by tag parsing state machine */ u16_t tag_insert_len; /* Length of insert in string tag_insert */ u8_t tag_name_len; /* Length of the tag name in string tag_name */ char tag_name[LWIP_HTTPD_MAX_TAG_NAME_LEN + 1]; /* Last tag name extracted */ char tag_insert[LWIP_HTTPD_MAX_TAG_INSERT_LEN + 1]; /* Insert string for tag_name */ enum tag_check_state tag_state; /* State of the tag processor */ #endif /* LWIP_HTTPD_SSI */ #if LWIP_HTTPD_CGI char *params[LWIP_HTTPD_MAX_CGI_PARAMETERS]; /* Params extracted from the request URI */ char *param_vals[LWIP_HTTPD_MAX_CGI_PARAMETERS]; /* Values for each extracted param */ #endif /* LWIP_HTTPD_CGI */ #if LWIP_HTTPD_DYNAMIC_HEADERS const char *hdrs[NUM_FILE_HDR_STRINGS]; /* HTTP headers to be sent. */ u16_t hdr_pos; /* The position of the first unsent header byte in the current string */ u16_t hdr_index; /* The index of the hdr string currently being sent. */ #endif /* LWIP_HTTPD_DYNAMIC_HEADERS */ #if LWIP_HTTPD_TIMING u32_t time_started; #endif /* LWIP_HTTPD_TIMING */ #if LWIP_HTTPD_SUPPORT_POST u32_t post_content_len_left; #endif /* LWIP_HTTPD_SUPPORT_POST*/ }; static err_t http_find_file(struct http_state *hs, const char *uri, int is_09); static err_t http_init_file(struct http_state *hs, struct fs_file *file, int is_09, const char *uri); static err_t http_poll(void *arg, struct tcp_pcb *pcb); #if LWIP_HTTPD_SSI /* SSI insert handler function pointer. */ tSSIHandler g_pfnSSIHandler = NULL; int g_iNumTags = 0; const char **g_ppcTags = NULL; #define LEN_TAG_LEAD_IN 5 const char * const g_pcTagLeadIn = ""; #endif /* LWIP_HTTPD_SSI */ #if LWIP_HTTPD_CGI /* CGI handler information */ const tCGI *g_pCGIs = NULL; int g_iNumCGIs = 0; #endif /* LWIP_HTTPD_CGI */ #if LWIP_HTTPD_STRNSTR_PRIVATE /** Like strstr but does not need 'buffer' to be NULL-terminated */ static char* strnstr(const char* buffer, const char* token, size_t n) { const char* p; int tokenlen = (int)strlen(token); if (tokenlen == 0) { return (char *)buffer; } for (p = buffer; *p && (p + tokenlen <= buffer + n); p++) { if ((*p == *token) && (strncmp(p, token, tokenlen) == 0)) { return (char *)p; } } return NULL; } #endif /* LWIP_HTTPD_STRNSTR_PRIVATE */ /** Allocate a struct http_state. */ static struct http_state* http_state_alloc(void) { struct http_state *ret; #if HTTPD_USE_MEM_POOL ret = (struct http_state *)memp_malloc(MEMP_HTTPD_STATE); #else /* HTTPD_USE_MEM_POOL */ ret = (struct http_state *)mem_malloc(sizeof(struct http_state)); #endif /* HTTPD_USE_MEM_POOL */ if (ret != NULL) { /* Initialize the structure. */ memset(ret, 0, sizeof(struct http_state)); #if LWIP_HTTPD_DYNAMIC_HEADERS /* Indicate that the headers are not yet valid */ ret->hdr_index = NUM_FILE_HDR_STRINGS; #endif /* LWIP_HTTPD_DYNAMIC_HEADERS */ } return ret; } /** Free a struct http_state. * Also frees the file data if dynamic. */ static void http_state_free(struct http_state *hs) { if (hs != NULL) { if(hs->handle) { #if LWIP_HTTPD_TIMING u32_t ms_needed = sys_now() - hs->time_started; u32_t needed = LWIP_MAX(1, (ms_needed/100)); LWIP_DEBUGF(HTTPD_DEBUG_TIMING, ("httpd: needed %"U32_F" ms to send file of %d bytes -> %"U32_F" bytes/sec\n", ms_needed, hs->handle->len, ((((u32_t)hs->handle->len) * 10) / needed))); #endif /* LWIP_HTTPD_TIMING */ fs_close(hs->handle); hs->handle = NULL; } #if LWIP_HTTPD_SSI || LWIP_HTTPD_DYNAMIC_HEADERS if (hs->buf != NULL) { mem_free(hs->buf); hs->buf = NULL; } #endif /* LWIP_HTTPD_SSI || LWIP_HTTPD_DYNAMIC_HEADERS */ #if HTTPD_USE_MEM_POOL memp_free(MEMP_HTTPD_STATE, hs); #else /* HTTPD_USE_MEM_POOL */ mem_free(hs); #endif /* HTTPD_USE_MEM_POOL */ } } /** * The connection shall be actively closed. * Reset the sent- and recv-callbacks. * * @param pcb the tcp pcb to reset callbacks * @param hs connection state to free */ static void http_close_conn(struct tcp_pcb *pcb, struct http_state *hs) { err_t err; LWIP_DEBUGF(HTTPD_DEBUG, ("Closing connection %p\n", (void*)pcb)); tcp_arg(pcb, NULL); tcp_recv(pcb, NULL); tcp_err(pcb, NULL); tcp_poll(pcb, NULL, 0); tcp_sent(pcb, NULL); http_state_free(hs); err = tcp_close(pcb); if (err != ERR_OK) { LWIP_DEBUGF(HTTPD_DEBUG, ("Error %d closing %p\n", err, (void*)pcb)); /* error closing, try again later in poll */ tcp_poll(pcb, http_poll, HTTPD_POLL_INTERVAL); } } #if LWIP_HTTPD_CGI /** * Extract URI parameters from the parameter-part of an URI in the form * "test.cgi?x=y" @todo: better explanation! * Pointers to the parameters are stored in hs->param_vals. * * @param hs http connection state * @param params pointer to the NULL-terminated parameter string from the URI * @return number of parameters extracted */ static int extract_uri_parameters(struct http_state *hs, char *params) { char *pair; char *equals; int loop; /* If we have no parameters at all, return immediately. */ if(!params || (params[0] == '\0')) { return(0); } /* Get a pointer to our first parameter */ pair = params; /* * Parse up to LWIP_HTTPD_MAX_CGI_PARAMETERS from the passed string and ignore the * remainder (if any) */ for(loop = 0; (loop < LWIP_HTTPD_MAX_CGI_PARAMETERS) && pair; loop++) { /* Save the name of the parameter */ hs->params[loop] = pair; /* Remember the start of this name=value pair */ equals = pair; /* Find the start of the next name=value pair and replace the delimiter * with a 0 to terminate the previous pair string. */ pair = strchr(pair, '&'); if(pair) { *pair = '\0'; pair++; } else { /* We didn't find a new parameter so find the end of the URI and * replace the space with a '\0' */ pair = strchr(equals, ' '); if(pair) { *pair = '\0'; } /* Revert to NULL so that we exit the loop as expected. */ pair = NULL; } /* Now find the '=' in the previous pair, replace it with '\0' and save * the parameter value string. */ equals = strchr(equals, '='); if(equals) { *equals = '\0'; hs->param_vals[loop] = equals + 1; } else { hs->param_vals[loop] = NULL; } } return loop; } #endif /* LWIP_HTTPD_CGI */ #if LWIP_HTTPD_SSI /** * Insert a tag (found in an shtml in the form of "" into the file. * The tag's name is stored in hs->tag_name (NULL-terminated), the replacement * should be written to hs->tag_insert (up to a length of LWIP_HTTPD_MAX_TAG_INSERT_LEN). * The amount of data written is stored to hs->tag_insert_len. * * @todo: return tag_insert_len - maybe it can be removed from struct http_state? * * @param hs http connection state */ static void get_tag_insert(struct http_state *hs) { int loop; size_t len; if(g_pfnSSIHandler && g_ppcTags && g_iNumTags) { /* Find this tag in the list we have been provided. */ for(loop = 0; loop < g_iNumTags; loop++) { if(strcmp(hs->tag_name, g_ppcTags[loop]) == 0) { hs->tag_insert_len = g_pfnSSIHandler(loop, hs->tag_insert, LWIP_HTTPD_MAX_TAG_INSERT_LEN); return; } } } /* If we drop out, we were asked to serve a page which contains tags that * we don't have a handler for. Merely echo back the tags with an error * marker. */ #define UNKNOWN_TAG1_TEXT "***UNKNOWN TAG " #define UNKNOWN_TAG1_LEN 18 #define UNKNOWN_TAG2_TEXT "***" #define UNKNOWN_TAG2_LEN 7 len = LWIP_MIN(strlen(hs->tag_name), LWIP_HTTPD_MAX_TAG_INSERT_LEN - (UNKNOWN_TAG1_LEN + UNKNOWN_TAG2_LEN)); MEMCPY(hs->tag_insert, UNKNOWN_TAG1_TEXT, UNKNOWN_TAG1_LEN); MEMCPY(&hs->tag_insert[UNKNOWN_TAG1_LEN], hs->tag_name, len); MEMCPY(&hs->tag_insert[UNKNOWN_TAG1_LEN + len], UNKNOWN_TAG2_TEXT, UNKNOWN_TAG2_LEN); hs->tag_insert[UNKNOWN_TAG1_LEN + len + UNKNOWN_TAG2_LEN] = 0; len = strlen(hs->tag_insert); LWIP_ASSERT("len <= 0xffff", len <= 0xffff); hs->tag_insert_len = (u16_t)len; } #endif /* LWIP_HTTPD_SSI */ #if LWIP_HTTPD_DYNAMIC_HEADERS /** * Generate the relevant HTTP headers for the given filename and write * them into the supplied buffer. Returns true on success or false on failure. * @todo: this returns void, not true or false! */ static void get_http_headers(struct http_state *pState, char *pszURI) { unsigned int iLoop; char *pszWork; char *pszExt; char *pszVars; /* Ensure that we initialize the loop counter. */ iLoop = 0; /* In all cases, the second header we send is the server identification so set it here. */ pState->hdrs[1] = g_psHTTPHeaderStrings[HTTP_HDR_SERVER]; /* Is this a normal file or the special case we use to send back the default "404: Page not found" response? */ if(pszURI == NULL) { pState->hdrs[0] = g_psHTTPHeaderStrings[HTTP_HDR_NOT_FOUND]; pState->hdrs[2] = g_psHTTPHeaderStrings[DEFAULT_404_HTML]; /* Set up to send the first header string. */ pState->hdr_index = 0; pState->hdr_pos = 0; return; } else { /* We are dealing with a particular filename. Look for one other special case. We assume that any filename with "404" in it must be indicative of a 404 server error whereas all other files require the 200 OK header. */ if(strstr(pszURI, "404")) { pState->hdrs[0] = g_psHTTPHeaderStrings[HTTP_HDR_NOT_FOUND]; } else { pState->hdrs[0] = g_psHTTPHeaderStrings[HTTP_HDR_OK]; } /* Determine if the URI has any variables and, if so, temporarily remove them. */ pszVars = strchr(pszURI, '?'); if(pszVars) { *pszVars = '\0'; } /* Get a pointer to the file extension. We find this by looking for the last occurrence of "." in the filename passed. */ pszExt = NULL; pszWork = strchr(pszURI, '.'); while(pszWork) { pszExt = pszWork + 1; pszWork = strchr(pszExt, '.'); } /* Now determine the content type and add the relevant header for that. */ for(iLoop = 0; (iLoop < NUM_HTTP_HEADERS) && pszExt; iLoop++) { /* Have we found a matching extension? */ if(!strcmp(g_psHTTPHeaders[iLoop].extension, pszExt)) { pState->hdrs[2] = g_psHTTPHeaderStrings[g_psHTTPHeaders[iLoop].headerIndex]; break; } } /* Reinstate the parameter marker if there was one in the original URI. */ if(pszVars) { *pszVars = '?'; } } /* Does the URL passed have any file extension? If not, we assume it is a special-case URL used for control state notification and we do not send any HTTP headers with the response. */ if(!pszExt) { /* Force the header index to a value indicating that all headers have already been sent. */ pState->hdr_index = NUM_FILE_HDR_STRINGS; } else { /* Did we find a matching extension? */ if(iLoop == NUM_HTTP_HEADERS) { /* No - use the default, plain text file type. */ pState->hdrs[2] = g_psHTTPHeaderStrings[HTTP_HDR_DEFAULT_TYPE]; } /* Set up to send the first header string. */ pState->hdr_index = 0; pState->hdr_pos = 0; } } #endif /* LWIP_HTTPD_DYNAMIC_HEADERS */ /** * Try to send more data on this pcb. * * @param pcb the pcb to send data * @param hs connection state */ static u8_t http_send_data(struct tcp_pcb *pcb, struct http_state *hs) { err_t err; u16_t len; u16_t mss; u8_t data_to_send = false; #if LWIP_HTTPD_DYNAMIC_HEADERS u16_t hdrlen, sendlen; #endif /* LWIP_HTTPD_DYNAMIC_HEADERS */ LWIP_DEBUGF(HTTPD_DEBUG | LWIP_DBG_TRACE, ("http_send_data: pcb=%p hs=%p left=%d\n", (void*)pcb, (void*)hs, hs != NULL ? hs->left : 0)); #if LWIP_HTTPD_DYNAMIC_HEADERS /* If we were passed a NULL state structure pointer, ignore the call. */ if (hs == NULL) { return 0; } /* Assume no error until we find otherwise */ err = ERR_OK; /* Do we have any more header data to send for this file? */ if(hs->hdr_index < NUM_FILE_HDR_STRINGS) { /* How much data can we send? */ len = tcp_sndbuf(pcb); sendlen = len; while(len && (hs->hdr_index < NUM_FILE_HDR_STRINGS) && sendlen) { /* How much do we have to send from the current header? */ hdrlen = (u16_t)strlen(hs->hdrs[hs->hdr_index]); /* How much of this can we send? */ sendlen = (len < (hdrlen - hs->hdr_pos)) ? len : (hdrlen - hs->hdr_pos); /* Send this amount of data or as much as we can given memory * constraints. */ do { err = tcp_write(pcb, (const void *)(hs->hdrs[hs->hdr_index] + hs->hdr_pos), sendlen, 0); if (err == ERR_MEM) { sendlen /= 2; } else if (err == ERR_OK) { /* Remember that we added some more data to be transmitted. */ data_to_send = true; } } while ((err == ERR_MEM) && sendlen); /* Fix up the header position for the next time round. */ hs->hdr_pos += sendlen; len -= sendlen; /* Have we finished sending this string? */ if(hs->hdr_pos == hdrlen) { /* Yes - move on to the next one */ hs->hdr_index++; hs->hdr_pos = 0; } } /* If we get here and there are still header bytes to send, we send * the header information we just wrote immediately. If there are no * more headers to send, but we do have file data to send, drop through * to try to send some file data too. */ if((hs->hdr_index < NUM_FILE_HDR_STRINGS) || !hs->file) { LWIP_DEBUGF(HTTPD_DEBUG, ("tcp_output\n")); return 1; } } #else /* LWIP_HTTPD_DYNAMIC_HEADERS */ /* Assume no error until we find otherwise */ err = ERR_OK; #endif /* LWIP_HTTPD_DYNAMIC_HEADERS */ /* Have we run out of file data to send? If so, we need to read the next * block from the file. */ if (hs->left == 0) { #if LWIP_HTTPD_SSI || LWIP_HTTPD_DYNAMIC_HEADERS int count; #endif /* LWIP_HTTPD_SSI || LWIP_HTTPD_DYNAMIC_HEADERS */ /* Do we have a valid file handle? */ if (hs->handle == NULL) { /* No - close the connection. */ http_close_conn(pcb, hs); return 0; } if (fs_bytes_left(hs->handle) <= 0) { /* We reached the end of the file so this request is done. * @todo: don't close here for HTTP/1.1? */ LWIP_DEBUGF(HTTPD_DEBUG, ("End of file.\n")); http_close_conn(pcb, hs); return 0; } #if LWIP_HTTPD_SSI || LWIP_HTTPD_DYNAMIC_HEADERS /* Do we already have a send buffer allocated? */ if(hs->buf) { /* Yes - get the length of the buffer */ count = hs->buf_len; } else { /* We don't have a send buffer so allocate one up to 2mss bytes long. */ count = 2 * tcp_mss(pcb); do { hs->buf = (char*)mem_malloc((mem_size_t)count); if (hs->buf != NULL) { hs->buf_len = count; break; } count = count / 2; } while (count > 100); /* Did we get a send buffer? If not, return immediately. */ if (hs->buf == NULL) { LWIP_DEBUGF(HTTPD_DEBUG, ("No buff\n")); return 0; } } /* Read a block of data from the file. */ LWIP_DEBUGF(HTTPD_DEBUG, ("Trying to read %d bytes.\n", count)); count = fs_read(hs->handle, hs->buf, count); if(count < 0) { /* We reached the end of the file so this request is done. * @todo: don't close here for HTTP/1.1? */ LWIP_DEBUGF(HTTPD_DEBUG, ("End of file.\n")); http_close_conn(pcb, hs); return 1; } /* Set up to send the block of data we just read */ LWIP_DEBUGF(HTTPD_DEBUG, ("Read %d bytes.\n", count)); hs->left = count; hs->file = hs->buf; #if LWIP_HTTPD_SSI hs->parse_left = count; hs->parsed = hs->buf; #endif /* LWIP_HTTPD_SSI */ #else /* LWIP_HTTPD_SSI || LWIP_HTTPD_DYNAMIC_HEADERS */ LWIP_ASSERT("SSI and DYNAMIC_HEADERS turned off but eof not reached", 0); #endif /* LWIP_HTTPD_SSI || LWIP_HTTPD_DYNAMIC_HEADERS */ } #if LWIP_HTTPD_SSI if(!hs->tag_check) { #endif /* LWIP_HTTPD_SSI */ /* We are not processing an SHTML file so no tag checking is necessary. * Just send the data as we received it from the file. */ /* We cannot send more data than space available in the send buffer. */ if (tcp_sndbuf(pcb) < hs->left) { len = tcp_sndbuf(pcb); } else { len = (u16_t)hs->left; LWIP_ASSERT("hs->left did not fit into u16_t!", (len == hs->left)); } mss = tcp_mss(pcb); if(len > (2 * mss)) { len = 2 * mss; } do { LWIP_DEBUGF(HTTPD_DEBUG | LWIP_DBG_TRACE, ("Sending %d bytes\n", len)); /* If the data is being read from a buffer in RAM, we need to copy it * into the PCB. If it's in flash, however, we can avoid the copy since * the data is obviously not going to be overwritten during the life * of the connection. */ err = tcp_write(pcb, hs->file, len, HTTP_IS_DATA_VOLATILE(hs)); if (err == ERR_MEM) { len /= 2; } } while ((err == ERR_MEM) && (len > 1)); if (err == ERR_OK) { data_to_send = true; hs->file += len; hs->left -= len; } #if LWIP_HTTPD_SSI } else { /* We are processing an SHTML file so need to scan for tags and replace * them with insert strings. We need to be careful here since a tag may * straddle the boundary of two blocks read from the file and we may also * have to split the insert string between two tcp_write operations. */ /* How much data could we send? */ len = tcp_sndbuf(pcb); /* Do we have remaining data to send before parsing more? */ if(hs->parsed > hs->file) { /* We cannot send more data than space available in the send buffer. */ if (tcp_sndbuf(pcb) < (hs->parsed - hs->file)) { len = tcp_sndbuf(pcb); } else { LWIP_ASSERT("Data size does not fit into u16_t!", (hs->parsed - hs->file) <= 0xffff); len = (u16_t)(hs->parsed - hs->file); } mss = tcp_mss(pcb); if(len > (2 * mss)) { len = 2 * mss; } do { LWIP_DEBUGF(HTTPD_DEBUG, ("Sending %d bytes\n", len)); err = tcp_write(pcb, hs->file, len, 0); if (err == ERR_MEM) { len /= 2; } } while (err == ERR_MEM && len > 1); if (err == ERR_OK) { data_to_send = true; hs->file += len; hs->left -= len; } /* If the send buffer is full, return now. */ if(tcp_sndbuf(pcb) == 0) { return data_to_send; } } LWIP_DEBUGF(HTTPD_DEBUG, ("State %d, %d left\n", hs->tag_state, hs->parse_left)); /* We have sent all the data that was already parsed so continue parsing * the buffer contents looking for SSI tags. */ while((hs->parse_left) && (err == ERR_OK)) { switch(hs->tag_state) { case TAG_NONE: /* We are not currently processing an SSI tag so scan for the * start of the lead-in marker. */ if(*hs->parsed == g_pcTagLeadIn[0]) { /* We found what could be the lead-in for a new tag so change * state appropriately. */ hs->tag_state = TAG_LEADIN; hs->tag_index = 1; } /* Move on to the next character in the buffer */ hs->parse_left--; hs->parsed++; break; case TAG_LEADIN: /* We are processing the lead-in marker, looking for the start of * the tag name. */ /* Have we reached the end of the leadin? */ if(hs->tag_index == LEN_TAG_LEAD_IN) { hs->tag_index = 0; hs->tag_state = TAG_FOUND; } else { /* Have we found the next character we expect for the tag leadin? */ if(*hs->parsed == g_pcTagLeadIn[hs->tag_index]) { /* Yes - move to the next one unless we have found the complete * leadin, in which case we start looking for the tag itself */ hs->tag_index++; } else { /* We found an unexpected character so this is not a tag. Move * back to idle state. */ hs->tag_state = TAG_NONE; } /* Move on to the next character in the buffer */ hs->parse_left--; hs->parsed++; } break; case TAG_FOUND: /* We are reading the tag name, looking for the start of the * lead-out marker and removing any whitespace found. */ /* Remove leading whitespace between the tag leading and the first * tag name character. */ if((hs->tag_index == 0) && ((*hs->parsed == ' ') || (*hs->parsed == '\t') || (*hs->parsed == '\n') || (*hs->parsed == '\r'))) { /* Move on to the next character in the buffer */ hs->parse_left--; hs->parsed++; break; } /* Have we found the end of the tag name? This is signalled by * us finding the first leadout character or whitespace */ if((*hs->parsed == g_pcTagLeadOut[0]) || (*hs->parsed == ' ') || (*hs->parsed == '\t') || (*hs->parsed == '\n') || (*hs->parsed == '\r')) { if(hs->tag_index == 0) { /* We read a zero length tag so ignore it. */ hs->tag_state = TAG_NONE; } else { /* We read a non-empty tag so go ahead and look for the * leadout string. */ hs->tag_state = TAG_LEADOUT; LWIP_ASSERT("hs->tag_index <= 0xff", hs->tag_index <= 0xff); hs->tag_name_len = (u8_t)hs->tag_index; hs->tag_name[hs->tag_index] = '\0'; if(*hs->parsed == g_pcTagLeadOut[0]) { hs->tag_index = 1; } else { hs->tag_index = 0; } } } else { /* This character is part of the tag name so save it */ if(hs->tag_index < LWIP_HTTPD_MAX_TAG_NAME_LEN) { hs->tag_name[hs->tag_index++] = *hs->parsed; } else { /* The tag was too long so ignore it. */ hs->tag_state = TAG_NONE; } } /* Move on to the next character in the buffer */ hs->parse_left--; hs->parsed++; break; /* * We are looking for the end of the lead-out marker. */ case TAG_LEADOUT: /* Remove leading whitespace between the tag leading and the first * tag leadout character. */ if((hs->tag_index == 0) && ((*hs->parsed == ' ') || (*hs->parsed == '\t') || (*hs->parsed == '\n') || (*hs->parsed == '\r'))) { /* Move on to the next character in the buffer */ hs->parse_left--; hs->parsed++; break; } /* Have we found the next character we expect for the tag leadout? */ if(*hs->parsed == g_pcTagLeadOut[hs->tag_index]) { /* Yes - move to the next one unless we have found the complete * leadout, in which case we need to call the client to process * the tag. */ /* Move on to the next character in the buffer */ hs->parse_left--; hs->parsed++; if(hs->tag_index == (LEN_TAG_LEAD_OUT - 1)) { /* Call the client to ask for the insert string for the * tag we just found. */ get_tag_insert(hs); /* Next time through, we are going to be sending data * immediately, either the end of the block we start * sending here or the insert string. */ hs->tag_index = 0; hs->tag_state = TAG_SENDING; hs->tag_end = hs->parsed; /* If there is any unsent data in the buffer prior to the * tag, we need to send it now. */ if(hs->tag_end > hs->file) { /* How much of the data can we send? */ if(len > hs->tag_end - hs->file) { len = (u16_t)(hs->tag_end - hs->file); } do { LWIP_DEBUGF(HTTPD_DEBUG, ("Sending %d bytes\n", len)); err = tcp_write(pcb, hs->file, len, 0); if (err == ERR_MEM) { len /= 2; } } while (err == ERR_MEM && (len > 1)); if (err == ERR_OK) { data_to_send = true; hs->file += len; hs->left -= len; } } } else { hs->tag_index++; } } else { /* We found an unexpected character so this is not a tag. Move * back to idle state. */ hs->parse_left--; hs->parsed++; hs->tag_state = TAG_NONE; } break; /* * We have found a valid tag and are in the process of sending * data as a result of that discovery. We send either remaining data * from the file prior to the insert point or the insert string itself. */ case TAG_SENDING: /* Do we have any remaining file data to send from the buffer prior * to the tag? */ if(hs->tag_end > hs->file) { /* How much of the data can we send? */ if(len > hs->tag_end - hs->file) { len = (u16_t)(hs->tag_end - hs->file); } do { LWIP_DEBUGF(HTTPD_DEBUG, ("Sending %d bytes\n", len)); err = tcp_write(pcb, hs->file, len, 0); if (err == ERR_MEM) { len /= 2; } } while (err == ERR_MEM && (len > 1)); if (err == ERR_OK) { data_to_send = true; hs->file += len; hs->left -= len; } } else { /* Do we still have insert data left to send? */ if(hs->tag_index < hs->tag_insert_len) { /* We are sending the insert string itself. How much of the * insert can we send? */ if(len > (hs->tag_insert_len - hs->tag_index)) { len = (hs->tag_insert_len - hs->tag_index); } do { LWIP_DEBUGF(HTTPD_DEBUG, ("Sending %d bytes\n", len)); /* * Note that we set the copy flag here since we only have a * single tag insert buffer per connection. If we don't do * this, insert corruption can occur if more than one insert * is processed before we call tcp_output. */ err = tcp_write(pcb, &(hs->tag_insert[hs->tag_index]), len, 1); if (err == ERR_MEM) { len /= 2; } } while (err == ERR_MEM && (len > 1)); if (err == ERR_OK) { data_to_send = true; hs->tag_index += len; /* Don't return here: keep on sending data */ } } else { /* We have sent all the insert data so go back to looking for * a new tag. */ LWIP_DEBUGF(HTTPD_DEBUG, ("Everything sent.\n")); hs->tag_index = 0; hs->tag_state = TAG_NONE; } } } } /* * If we drop out of the end of the for loop, this implies we must have * file data to send so send it now. In TAG_SENDING state, we've already * handled this so skip the send if that's the case. */ if((hs->tag_state != TAG_SENDING) && (hs->parsed > hs->file)) { /* We cannot send more data than space available in the send buffer. */ if (tcp_sndbuf(pcb) < (hs->parsed - hs->file)) { len = tcp_sndbuf(pcb); } else { LWIP_ASSERT("Data size does not fit into u16_t!", (hs->parsed - hs->file) <= 0xffff); len = (u16_t)(hs->parsed - hs->file); } if(len > (2 * tcp_mss(pcb))) { len = 2 * tcp_mss(pcb); } do { LWIP_DEBUGF(HTTPD_DEBUG, ("Sending %d bytes\n", len)); err = tcp_write(pcb, hs->file, len, 0); if (err == ERR_MEM) { len /= 2; } } while (err == ERR_MEM && len > 1); if (err == ERR_OK) { data_to_send = true; hs->file += len; hs->left -= len; } } } #endif /* LWIP_HTTPD_SSI */ if((hs->left == 0) && (fs_bytes_left(hs->handle) <= 0)) { /* We reached the end of the file so this request is done. * This adds the FIN flag right into the last data segment. * @todo: don't close here for HTTP/1.1? */ LWIP_DEBUGF(HTTPD_DEBUG, ("End of file.\n")); http_close_conn(pcb, hs); return 0; } LWIP_DEBUGF(HTTPD_DEBUG | LWIP_DBG_TRACE, ("send_data end.\n")); return data_to_send; } #if LWIP_HTTPD_SUPPORT_EXTSTATUS /** Initialize a http connection with a file to send for an error message * * @param hs http connection state * @param error_nr HTTP error number * @return ERR_OK if file was found and hs has been initialized correctly * another err_t otherwise */ static err_t http_find_error_file(struct http_state *hs, u16_t error_nr) { const char *uri1, *uri2; struct fs_file *file; if (error_nr == 501) { uri1 = "/501.html"; uri2 = "/501.htm"; } else { /* 400 (bad request is the default) */ uri1 = "/400.html"; uri2 = "/400.htm"; } file = fs_open(uri1); if (file == NULL) { file = fs_open(uri2); if (file == NULL) { LWIP_DEBUGF(HTTPD_DEBUG, ("Error page for error %"U16_F" not found\n", error_nr)); return ERR_ARG; } } return http_init_file(hs, file, 0, NULL); } #else /* LWIP_HTTPD_SUPPORT_EXTSTATUS */ #define http_find_error_file(hs, error_nr) ERR_ARG #endif /* LWIP_HTTPD_SUPPORT_EXTSTATUS */ /** * Get the file struct for a 404 error page. * Tries some file names and returns NULL if none found. * * @param uri pointer that receives the actual file name URI * @return file struct for the error page or NULL no matching file was found */ static struct fs_file * http_get_404_file(const char **uri) { struct fs_file *file; *uri = "/404.html"; file = fs_open(*uri); if(file == NULL) { /* 404.html doesn't exist. Try 404.htm instead. */ *uri = "/404.htm"; file = fs_open(*uri); if(file == NULL) { /* 404.htm doesn't exist either. Indicate to the caller that it should * send back a default 404 page. */ *uri = NULL; } } return file; } #if LWIP_HTTPD_SUPPORT_POST /** Pass received POST body data to the application and correctly handle * returning a response document or closing the connection. * ATTENTION: The application is responsible for the pbuf now, so don't free it! * * @param hs http connection state * @param p pbuf to pass to the application * @return ERR_OK if passed successfully, another err_t if the response file * hasn't been found (after POST finished) */ static err_t http_post_rxpbuf(struct http_state *hs, struct pbuf *p) { err_t err; /* adjust remaining Content-Length */ if (hs->post_content_len_left < p->tot_len) { hs->post_content_len_left = 0; } else { hs->post_content_len_left -= p->tot_len; } err = httpd_post_receive_data(hs, p); if ((err != ERR_OK) || (hs->post_content_len_left == 0)) { /* application error or POST finished */ /* NULL-terminate the buffer */ http_post_response_filename[0] = 0; httpd_post_finished(hs, http_post_response_filename, LWIP_HTTPD_POST_MAX_RESPONSE_URI_LEN); return http_find_file(hs, http_post_response_filename, 0); } return ERR_OK; } /** Handle a post request. Called from http_parse_request when method 'POST' * is found. * * @param p The input pbuf (containing the POST header and body). * @param hs The http connection state. * @param data HTTP request (header and part of body) from input pbuf(s). * @param data_len Size of 'data'. * @param uri The HTTP URI parsed from input pbuf(s). * @param uri_end Pointer to the end of 'uri' (here, the rest of the HTTP * header starts). * @return ERR_OK: POST correctly parsed and accepted by the application. * ERR_INPROGRESS: POST not completely parsed (no error yet) * another err_t: Error parsing POST or denied by the application */ static err_t http_post_request(struct pbuf **inp, struct http_state *hs, char *data, u16_t data_len, char *uri, char *uri_end) { /* @todo: - parse content-length - get data from this first packet - call application callback with URI */ err_t err; /* search for end-of-header (first double-CRLF) */ char* crlfcrlf = strnstr(uri_end + 1, CRLF CRLF, data_len - (uri_end + 1 - data)); if (crlfcrlf != NULL) { /* search for "Content-Length: " */ #define HTTP_HDR_CONTENT_LEN "Content-Length: " #define HTTP_HDR_CONTENT_LEN_LEN 16 #define HTTP_HDR_CONTENT_LEN_DIGIT_MAX_LEN 10 char *scontent_len = strnstr(uri_end + 1, HTTP_HDR_CONTENT_LEN, crlfcrlf - (uri_end + 1)); if (scontent_len != NULL) { char *scontent_len_end = strnstr(scontent_len + HTTP_HDR_CONTENT_LEN_LEN, CRLF, HTTP_HDR_CONTENT_LEN_DIGIT_MAX_LEN); if (scontent_len_end != NULL) { int content_len; char *conten_len_num = scontent_len + HTTP_HDR_CONTENT_LEN_LEN; *scontent_len_end = 0; content_len = atoi(conten_len_num); if (content_len > 0) { /* adjust length of HTTP header passed to application */ u16_t hdr_len = LWIP_MIN(data_len, crlfcrlf + 4 - data); http_post_response_filename[0] = 0; err = httpd_post_begin(hs, uri, data, hdr_len, content_len, http_post_response_filename, LWIP_HTTPD_POST_MAX_RESPONSE_URI_LEN); if (err == ERR_OK) { /* try to pass in data of the first pbuf(s) */ struct pbuf *q = *inp; u16_t start_offset = hdr_len; /* set the Content-Length to be received for this POST */ hs->post_content_len_left = (u32_t)content_len; /* get to the pbuf where the body starts */ while((q != NULL) && (q->len <= start_offset)) { struct pbuf *head = q; start_offset -= q->len; q = q->next; /* free the head pbuf */ head->next = NULL; pbuf_free(head); } *inp = NULL; if (q != NULL) { /* hide the remaining HTTP header */ pbuf_header(q, start_offset); return http_post_rxpbuf(hs, q); } else { return ERR_OK; } } else { /* return file passed from application */ return http_find_file(hs, http_post_response_filename, 0); } } else { LWIP_DEBUGF(HTTPD_DEBUG, ("POST received invalid Content-Length: %s\n", conten_len_num)); return ERR_ARG; } } } } /* if we come here, the POST is incomplete */ #if LWIP_HTTPD_SUPPORT_REQUESTLIST return ERR_INPROGRESS; #else /* LWIP_HTTPD_SUPPORT_REQUESTLIST */ return ERR_ARG; #endif /* LWIP_HTTPD_SUPPORT_REQUESTLIST */ } #endif /* LWIP_HTTPD_SUPPORT_POST */ /** * When data has been received in the correct state, try to parse it * as a HTTP request. * * @param p the received pbuf * @param hs the connection state * @return ERR_OK if request was OK and hs has been initialized correctly * ERR_INPROGRESS if request was OK so far but not fully received * another err_t otherwise */ static err_t http_parse_request(struct pbuf **inp, struct http_state *hs) { char *data; char *crlf; u16_t data_len; struct pbuf *p = *inp; #if LWIP_HTTPD_SUPPORT_REQUESTLIST u16_t clen; #endif /* LWIP_HTTPD_SUPPORT_REQUESTLIST */ #if LWIP_HTTPD_SUPPORT_POST err_t err; #endif /* LWIP_HTTPD_SUPPORT_POST */ LWIP_ASSERT("p != NULL", p != NULL); LWIP_ASSERT("hs != NULL", hs != NULL); if ((hs->handle != NULL) || (hs->file != NULL)) { LWIP_DEBUGF(HTTPD_DEBUG, ("Received data while sending a file\n")); /* already sending a file */ /* @todo: abort? */ return ERR_USE; } #if LWIP_HTTPD_SUPPORT_REQUESTLIST LWIP_DEBUGF(HTTPD_DEBUG, ("Received %"U16_F" bytes\n", p->tot_len)); /* first check allowed characters in this pbuf? */ /* enqueue the pbuf */ if (hs->req == NULL) { LWIP_DEBUGF(HTTPD_DEBUG, ("First pbuf\n")); hs->req = p; } else { LWIP_DEBUGF(HTTPD_DEBUG, ("pbuf enqueued\n")); pbuf_cat(hs->req, p); } if (hs->req->next != NULL) { data_len = LWIP_MIN(hs->req->tot_len, LWIP_HTTPD_MAX_REQ_LENGTH); pbuf_copy_partial(hs->req, httpd_req_buf, data_len, 0); data = httpd_req_buf; } else #endif /* LWIP_HTTPD_SUPPORT_REQUESTLIST */ { data = (char *)p->payload; data_len = p->len; if (p->len != p->tot_len) { LWIP_DEBUGF(HTTPD_DEBUG, ("Warning: incomplete header due to chained pbufs\n")); } } /* received enough data for minimal request? */ if (data_len >= MIN_REQ_LEN) { /* wait for CRLF before parsing anything */ crlf = strnstr(data, CRLF, data_len); if (crlf != NULL) { #if LWIP_HTTPD_SUPPORT_POST int is_post = 0; #endif /* LWIP_HTTPD_SUPPORT_POST */ int is_09 = 0; char *sp1, *sp2; u16_t left_len, uri_len; LWIP_DEBUGF(HTTPD_DEBUG | LWIP_DBG_TRACE, ("CRLF received, parsing request\n")); /* parse method */ if (!strncmp(data, "GET ", 4)) { sp1 = data + 3; /* received GET request */ LWIP_DEBUGF(HTTPD_DEBUG | LWIP_DBG_TRACE, ("Received GET request\"\n")); #if LWIP_HTTPD_SUPPORT_POST } else if (!strncmp(data, "POST ", 5)) { /* store request type */ is_post = 1; sp1 = data + 4; /* received GET request */ LWIP_DEBUGF(HTTPD_DEBUG | LWIP_DBG_TRACE, ("Received POST request\n")); #endif /* LWIP_HTTPD_SUPPORT_POST */ } else { /* null-terminate the METHOD (pbuf is freed anyway wen returning) */ data[4] = 0; /* unsupported method! */ LWIP_DEBUGF(HTTPD_DEBUG, ("Unsupported request method (not implemented): \"%s\"\n", data)); return http_find_error_file(hs, 501); } /* if we come here, method is OK, parse URI */ left_len = data_len - ((sp1 +1) - data); sp2 = strnstr(sp1 + 1, " ", left_len); #if LWIP_HTTPD_SUPPORT_V09 if (sp2 == NULL) { /* HTTP 0.9: respond with correct protocol version */ sp2 = strnstr(sp1 + 1, CRLF, left_len); is_09 = 1; #if LWIP_HTTPD_SUPPORT_POST if (is_post) { /* HTTP/0.9 does not support POST */ goto badrequest; } #endif /* LWIP_HTTPD_SUPPORT_POST */ } #endif /* LWIP_HTTPD_SUPPORT_V09 */ uri_len = sp2 - (sp1 + 1); if ((sp2 != 0) && (sp2 > sp1)) { char *uri = sp1 + 1; /* null-terminate the METHOD (pbuf is freed anyway wen returning) */ *sp1 = 0; uri[uri_len] = 0; LWIP_DEBUGF(HTTPD_DEBUG, ("Received \"%s\" request for URI: \"%s\"\n", data, uri)); #if LWIP_HTTPD_SUPPORT_POST if (is_post) { #if LWIP_HTTPD_SUPPORT_REQUESTLIST struct pbuf **q = &hs->req; #else /* LWIP_HTTPD_SUPPORT_REQUESTLIST */ struct pbuf **q = inp; #endif /* LWIP_HTTPD_SUPPORT_REQUESTLIST */ err = http_post_request(q, hs, data, data_len, uri, sp2); if (err != ERR_OK) { /* restore header for next try */ *sp1 = ' '; *sp2 = ' '; uri[uri_len] = ' '; } if (err == ERR_ARG) { goto badrequest; } return err; } else #endif /* LWIP_HTTPD_SUPPORT_POST */ { return http_find_file(hs, uri, is_09); } } else { LWIP_DEBUGF(HTTPD_DEBUG, ("invalid URI\n")); } } } #if LWIP_HTTPD_SUPPORT_REQUESTLIST clen = pbuf_clen(hs->req); if ((hs->req->tot_len <= LWIP_HTTPD_REQ_BUFSIZE) && (clen <= LWIP_HTTPD_REQ_QUEUELEN)) { /* request not fully received (too short or CRLF is missing) */ return ERR_INPROGRESS; } else #endif /* LWIP_HTTPD_SUPPORT_REQUESTLIST */ { #if LWIP_HTTPD_SUPPORT_POST badrequest: #endif /* LWIP_HTTPD_SUPPORT_POST */ LWIP_DEBUGF(HTTPD_DEBUG, ("bad request\n")); /* could not parse request */ return http_find_error_file(hs, 400); } } /** Try to find the file specified by uri and, if found, initialize hs * accordingly. * * @param hs the connection state * @param uri the HTTP header URI * @param is_09 1 if the request is HTTP/0.9 (no HTTP headers in response) * @return ERR_OK if file was found and hs has been initialized correctly * another err_t otherwise */ static err_t http_find_file(struct http_state *hs, const char *uri, int is_09) { size_t loop; struct fs_file *file = NULL; /* default is request not supported, until it can be parsed */ #if LWIP_HTTPD_CGI int i; int count; char *params; #endif /* LWIP_HTTPD_CGI */ #if LWIP_HTTPD_SSI /* * By default, assume we will not be processing server-side-includes * tags */ hs->tag_check = false; #endif /* LWIP_HTTPD_SSI */ /* Have we been asked for the default root file? */ if((uri[0] == '/') && (uri[1] == 0)) { /* Try each of the configured default filenames until we find one that exists. */ for (loop = 0; loop < NUM_DEFAULT_FILENAMES; loop++) { LWIP_DEBUGF(HTTPD_DEBUG | LWIP_DBG_TRACE, ("Looking for %s...\n", g_psDefaultFilenames[loop].name)); file = fs_open((char *)g_psDefaultFilenames[loop].name); uri = (char *)g_psDefaultFilenames[loop].name; if(file != NULL) { LWIP_DEBUGF(HTTPD_DEBUG | LWIP_DBG_TRACE, ("Opened.\n")); #if LWIP_HTTPD_SSI hs->tag_check = g_psDefaultFilenames[loop].shtml; #endif /* LWIP_HTTPD_SSI */ break; } } if (file == NULL) { /* None of the default filenames exist so send back a 404 page */ file = http_get_404_file(&uri); #if LWIP_HTTPD_SSI hs->tag_check = false; #endif /* LWIP_HTTPD_SSI */ } } else { /* No - we've been asked for a specific file. */ #if LWIP_HTTPD_CGI /* First, isolate the base URI (without any parameters) */ params = (char *)strchr(uri, '?'); if (params != NULL) { /* URI contains parameters. NULL-terminate the base URI */ *params = '\0'; params++; } /* Does the base URI we have isolated correspond to a CGI handler? */ if (g_iNumCGIs && g_pCGIs) { for (i = 0; i < g_iNumCGIs; i++) { if (strcmp(uri, g_pCGIs[i].pcCGIName) == 0) { /* * We found a CGI that handles this URI so extract the * parameters and call the handler. */ count = extract_uri_parameters(hs, params); uri = g_pCGIs[i].pfnCGIHandler(i, count, hs->params, hs->param_vals); break; } } /* Did we handle this URL as a CGI? If not, reinstate the * original URL and pass it to the file system directly. */ if (i == g_iNumCGIs) { /* Replace the ? marker at the beginning of the parameters */ if (params != NULL) { params--; *params = '?'; } } } #endif /* LWIP_HTTPD_CGI */ LWIP_DEBUGF(HTTPD_DEBUG | LWIP_DBG_TRACE, ("Opening %s\n", uri)); file = fs_open(uri); if (file == NULL) { file = http_get_404_file(&uri); } #if LWIP_HTTPD_SSI else { /* * See if we have been asked for an shtml file and, if so, * enable tag checking. */ hs->tag_check = false; for (loop = 0; loop < NUM_SHTML_EXTENSIONS; loop++) { if (strstr(uri, g_pcSSIExtensions[loop])) { hs->tag_check = true; break; } } } #endif /* LWIP_HTTPD_SSI */ } return http_init_file(hs, file, is_09, uri); } /** Initialize a http connection with a file to send (if found). * Called by http_find_file and http_find_error_file. * * @param hs http connection state * @param file file structure to send (or NULL if not found) * @param is_09 1 if the request is HTTP/0.9 (no HTTP headers in response) * @param uri the HTTP header URI * @return ERR_OK if file was found and hs has been initialized correctly * another err_t otherwise */ static err_t http_init_file(struct http_state *hs, struct fs_file *file, int is_09, const char *uri) { err_t file_found = ERR_ARG; if (file != NULL) { /* file opened, initialise struct http_state */ #if LWIP_HTTPD_SSI hs->tag_index = 0; hs->tag_state = TAG_NONE; hs->parsed = file->data; hs->parse_left = file->len; hs->tag_end = file->data; #endif /* LWIP_HTTPD_SSI */ hs->handle = file; hs->file = (char*)file->data; LWIP_ASSERT("File length must be positive!", (file->len >= 0)); hs->left = file->len; hs->retries = 0; file_found = ERR_OK; #if LWIP_HTTPD_TIMING hs->time_started = sys_now(); #endif /* LWIP_HTTPD_TIMING */ #if !LWIP_HTTPD_DYNAMIC_HEADERS LWIP_ASSERT("HTTP headers not included in file system", hs->handle->http_header_included); #endif /* !LWIP_HTTPD_DYNAMIC_HEADERS */ #if LWIP_HTTPD_SUPPORT_V09 if (hs->handle->http_header_included && is_09) { /* HTTP/0.9 responses are sent without HTTP header, search for the end of the header. */ char *file_start = strnstr(hs->file, CRLF CRLF, hs->left); if (file_start != NULL) { size_t diff = file_start + 4 - hs->file; hs->file += diff; hs->left -= (u32_t)diff; } } #endif /* LWIP_HTTPD_SUPPORT_V09*/ } else { hs->handle = NULL; hs->file = NULL; hs->left = 0; hs->retries = 0; } #if LWIP_HTTPD_DYNAMIC_HEADERS /* Determine the HTTP headers to send based on the file extension of * the requested URI. */ if (hs->handle && !hs->handle->http_header_included) { get_http_headers(hs, (char*)uri); } #else /* LWIP_HTTPD_DYNAMIC_HEADERS */ LWIP_UNUSED_ARG(uri); #endif /* LWIP_HTTPD_DYNAMIC_HEADERS */ return file_found; } /** * The pcb had an error and is already deallocated. * The argument might still be valid (if != NULL). */ static void http_err(void *arg, err_t err) { struct http_state *hs = (struct http_state *)arg; LWIP_UNUSED_ARG(err); LWIP_DEBUGF(HTTPD_DEBUG, ("http_err: %s", lwip_strerr(err))); if (hs != NULL) { http_state_free(hs); } } /** * Data has been sent and acknowledged by the remote host. * This means that more data can be sent. */ static err_t http_sent(void *arg, struct tcp_pcb *pcb, u16_t len) { struct http_state *hs = (struct http_state *)arg; LWIP_DEBUGF(HTTPD_DEBUG | LWIP_DBG_TRACE, ("http_sent %p\n", (void*)pcb)); LWIP_UNUSED_ARG(len); if (hs == NULL) { return ERR_OK; } hs->retries = 0; http_send_data(pcb, hs); return ERR_OK; } /** * The poll function is called every 2nd second. * If there has been no data sent (which resets the retries) in 8 seconds, close. * If the last portion of a file has not been sent in 2 seconds, close. * * This could be increased, but we don't want to waste resources for bad connections. */ static err_t http_poll(void *arg, struct tcp_pcb *pcb) { struct http_state *hs = (struct http_state *)arg; LWIP_DEBUGF(HTTPD_DEBUG | LWIP_DBG_TRACE, ("http_poll: pcb=%p hs=%p pcb_state=%s\n", (void*)pcb, (void*)hs, tcp_debug_state_str(pcb->state))); if (hs == NULL) { /* arg is null, close. */ LWIP_DEBUGF(HTTPD_DEBUG, ("http_poll: arg is NULL, close\n")); http_close_conn(pcb, hs); return ERR_OK; } else { hs->retries++; if (hs->retries == HTTPD_MAX_RETRIES) { LWIP_DEBUGF(HTTPD_DEBUG, ("http_poll: too many retries, close\n")); http_close_conn(pcb, hs); return ERR_OK; } /* If this connection has a file open, try to send some more data. If * it has not yet received a GET request, don't do this since it will * cause the connection to close immediately. */ if(hs && (hs->handle)) { LWIP_DEBUGF(HTTPD_DEBUG | LWIP_DBG_TRACE, ("http_poll: try to send more data\n")); if(http_send_data(pcb, hs)) { /* If we wrote anything to be sent, go ahead and send it now. */ LWIP_DEBUGF(HTTPD_DEBUG | LWIP_DBG_TRACE, ("tcp_output\n")); tcp_output(pcb); } } } return ERR_OK; } /** * Data has been received on this pcb. * For HTTP 1.0, this should normally only happen once (if the request fits in one packet). */ static err_t http_recv(void *arg, struct tcp_pcb *pcb, struct pbuf *p, err_t err) { err_t parsed = ERR_ABRT; struct http_state *hs = (struct http_state *)arg; LWIP_DEBUGF(HTTPD_DEBUG | LWIP_DBG_TRACE, ("http_recv: pcb=%p pbuf=%p err=%s\n", (void*)pcb, (void*)p, lwip_strerr(err))); if (p != NULL) { /* Inform TCP that we have taken the data. */ tcp_recved(pcb, p->tot_len); } if ((err != ERR_OK) || (p == NULL) || (hs == NULL)) { /* error or closed by other side? */ if (p != NULL) { pbuf_free(p); } if (hs == NULL) { /* this should not happen, only to be robust */ LWIP_DEBUGF(HTTPD_DEBUG, ("Error, http_recv: hs is NULL, close\n")); } http_close_conn(pcb, hs); return ERR_OK; } #if LWIP_HTTPD_SUPPORT_POST if (hs->post_content_len_left > 0) { /* this is data for a POST, pass the complete pbuf to the application */ http_post_rxpbuf(hs, p); /* pbuf is passed to the application, don't free it! */ if (hs->post_content_len_left == 0) { /* all data received, send response or close connection */ http_send_data(pcb, hs); } return ERR_OK; } else #endif /* LWIP_HTTPD_SUPPORT_POST */ { if (hs->handle == NULL) { parsed = http_parse_request(&p, hs); LWIP_ASSERT("http_parse_request: unexpected return value", parsed == ERR_OK || parsed == ERR_INPROGRESS ||parsed == ERR_ARG || parsed == ERR_USE); } else { LWIP_DEBUGF(HTTPD_DEBUG, ("http_recv: already sending data\n")); } #if LWIP_HTTPD_SUPPORT_REQUESTLIST if (parsed != ERR_INPROGRESS) { /* request fully parsed or error */ if (hs->req != NULL) { pbuf_free(hs->req); hs->req = NULL; } } #else /* LWIP_HTTPD_SUPPORT_REQUESTLIST */ if (p != NULL) { /* pbuf not passed to application, free it now */ pbuf_free(p); } #endif /* LWIP_HTTPD_SUPPORT_REQUESTLIST */ if (parsed == ERR_OK) { #if LWIP_HTTPD_SUPPORT_POST if (hs->post_content_len_left == 0) #endif /* LWIP_HTTPD_SUPPORT_POST */ { LWIP_DEBUGF(HTTPD_DEBUG | LWIP_DBG_TRACE, ("http_recv: data %p len %"S32_F"\n", hs->file, hs->left)); http_send_data(pcb, hs); } } else if (parsed == ERR_ARG) { /* @todo: close on ERR_USE? */ http_close_conn(pcb, hs); } } return ERR_OK; } /** * A new incoming connection has been accepted. */ static err_t http_accept(void *arg, struct tcp_pcb *pcb, err_t err) { struct http_state *hs; struct tcp_pcb_listen *lpcb = (struct tcp_pcb_listen*)arg; LWIP_UNUSED_ARG(err); LWIP_DEBUGF(HTTPD_DEBUG, ("http_accept %p / %p\n", (void*)pcb, arg)); /* Decrease the listen backlog counter */ tcp_accepted(lpcb); /* Set priority */ tcp_setprio(pcb, HTTPD_TCP_PRIO); /* Allocate memory for the structure that holds the state of the connection - initialized by that function. */ hs = http_state_alloc(); if (hs == NULL) { LWIP_DEBUGF(HTTPD_DEBUG, ("http_accept: Out of memory, RST\n")); return ERR_MEM; } /* Tell TCP that this is the structure we wish to be passed for our callbacks. */ tcp_arg(pcb, hs); /* Set up the various callback functions */ tcp_recv(pcb, http_recv); tcp_err(pcb, http_err); tcp_poll(pcb, http_poll, HTTPD_POLL_INTERVAL); tcp_sent(pcb, http_sent); return ERR_OK; } /** * Initialize the httpd with the specified local address. */ static void httpd_init_addr(ip_addr_t *local_addr) { struct tcp_pcb *pcb; err_t err; pcb = tcp_new(); LWIP_ASSERT("httpd_init: tcp_new failed", pcb != NULL); tcp_setprio(pcb, HTTPD_TCP_PRIO); /* set SOF_REUSEADDR here to explicitly bind httpd to multiple interfaces */ err = tcp_bind(pcb, local_addr, HTTPD_SERVER_PORT); LWIP_ASSERT("httpd_init: tcp_bind failed", err == ERR_OK); pcb = tcp_listen(pcb); LWIP_ASSERT("httpd_init: tcp_listen failed", pcb != NULL); /* initialize callback arg and accept callback */ tcp_arg(pcb, pcb); tcp_accept(pcb, http_accept); } /** * Initialize the httpd: set up a listening PCB and bind it to the defined port */ void httpd_init(void) { LWIP_DEBUGF(HTTPD_DEBUG, ("httpd_init\n")); httpd_init_addr(IP_ADDR_ANY); } #if LWIP_HTTPD_SSI /** * Set the SSI handler function. * * @param ssi_handler the SSI handler function * @param tags an array of SSI tag strings to search for in SSI-enabled files * @param num_tags number of tags in the 'tags' array */ void http_set_ssi_handler(tSSIHandler ssi_handler, const char **tags, int num_tags) { LWIP_DEBUGF(HTTPD_DEBUG, ("http_set_ssi_handler\n")); LWIP_ASSERT("no ssi_handler given", ssi_handler != NULL); LWIP_ASSERT("no tags given", tags != NULL); LWIP_ASSERT("invalid number of tags", num_tags > 0); g_pfnSSIHandler = ssi_handler; g_ppcTags = tags; g_iNumTags = num_tags; } #endif /* LWIP_HTTPD_SSI */ #if LWIP_HTTPD_CGI /** * Set an array of CGI filenames/handler functions * * @param cgis an array of CGI filenames/handler functions * @param num_handlers number of elements in the 'cgis' array */ void http_set_cgi_handlers(const tCGI *cgis, int num_handlers) { LWIP_ASSERT("no cgis given", cgis != NULL); LWIP_ASSERT("invalid number of handlers", num_handlers > 0); g_pCGIs = cgis; g_iNumCGIs = num_handlers; } #endif /* LWIP_HTTPD_CGI */ #endif /* LWIP_TCP */