// Copyright 2018 Espressif Systems (Shanghai) PTE LTD // // Licensed under the Apache License, Version 2.0 (the "License"); // you may not use this file except in compliance with the License. // You may obtain a copy of the License at // // http://www.apache.org/licenses/LICENSE-2.0 // // Unless required by applicable law or agreed to in writing, software // distributed under the License is distributed on an "AS IS" BASIS, // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. // See the License for the specific language governing permissions and // limitations under the License. #include #include #include #include #include #include #include "esp_httpd_priv.h" #include "osal.h" static const char *TAG = "httpd_parse"; typedef struct { /* Parser settings for http_parser_execute() */ http_parser_settings settings; /* Request being parsed */ struct httpd_req *req; /* Status of the parser describes the part of the * HTTP request packet being processed at any moment. */ enum { PARSING_IDLE = 0, PARSING_URL, PARSING_HDR_FIELD, PARSING_HDR_VALUE, PARSING_BODY, PARSING_COMPLETE, PARSING_FAILED } status; /* Response error code in case of PARSING_FAILED */ httpd_err_code_t error; /* For storing last callback parameters */ struct { const char *at; size_t length; } last; /* State variables */ bool paused; /*!< Parser is paused */ size_t pre_parsed; /*!< Length of data to be skipped while parsing */ size_t raw_datalen; /*!< Full length of the raw data in scratch buffer */ } parser_data_t; static esp_err_t verify_url (http_parser *parser) { parser_data_t *parser_data = (parser_data_t *) parser->data; struct httpd_req *r = parser_data->req; struct httpd_req_aux *ra = r->aux; struct http_parser_url *res = &ra->url_parse_res; /* Get previous values of the parser callback arguments */ const char *at = parser_data->last.at; size_t length = parser_data->last.length; if ((r->method = parser->method) < 0) { ESP_LOGW(TAG, LOG_FMT("HTTP Operation not supported")); parser_data->error = HTTPD_501_METHOD_NOT_IMPLEMENTED; return ESP_FAIL; } if (sizeof(r->uri) < (length + 1)) { ESP_LOGW(TAG, LOG_FMT("URI length (%d) greater than supported (%d)"), length, sizeof(r->uri)); parser_data->error = HTTPD_414_URI_TOO_LONG; return ESP_FAIL; } /* Keep URI with terminating null character. Note URI string pointed * by 'at' is not NULL terminated, therefore use length provided by * parser while copying the URI to buffer */ strlcpy((char *)r->uri, at, (length + 1)); ESP_LOGD(TAG, LOG_FMT("received URI = %s"), r->uri); /* Make sure version is HTTP/1.1 */ if ((parser->http_major != 1) && (parser->http_minor != 1)) { ESP_LOGW(TAG, LOG_FMT("unsupported HTTP version = %d.%d"), parser->http_major, parser->http_minor); parser_data->error = HTTPD_505_VERSION_NOT_SUPPORTED; return ESP_FAIL; } /* Parse URL and keep result for later */ http_parser_url_init(res); if (http_parser_parse_url(r->uri, strlen(r->uri), r->method == HTTP_CONNECT, res)) { ESP_LOGW(TAG, LOG_FMT("http_parser_parse_url failed with errno = %d"), parser->http_errno); parser_data->error = HTTPD_400_BAD_REQUEST; return ESP_FAIL; } return ESP_OK; } /* http_parser callback on finding url in HTTP request * Will be invoked ATLEAST once every packet */ static esp_err_t cb_url(http_parser *parser, const char *at, size_t length) { parser_data_t *parser_data = (parser_data_t *) parser->data; if (parser_data->status == PARSING_IDLE) { ESP_LOGD(TAG, LOG_FMT("message begin")); /* Store current values of the parser callback arguments */ parser_data->last.at = at; parser_data->last.length = 0; parser_data->status = PARSING_URL; } else if (parser_data->status != PARSING_URL) { ESP_LOGE(TAG, LOG_FMT("unexpected state transition")); parser_data->error = HTTPD_500_INTERNAL_SERVER_ERROR; parser_data->status = PARSING_FAILED; return ESP_FAIL; } ESP_LOGD(TAG, LOG_FMT("processing url = %.*s"), length, at); /* Update length of URL string */ if ((parser_data->last.length += length) > HTTPD_MAX_URI_LEN) { ESP_LOGW(TAG, LOG_FMT("URI length (%d) greater than supported (%d)"), parser_data->last.length, HTTPD_MAX_URI_LEN); parser_data->error = HTTPD_414_URI_TOO_LONG; parser_data->status = PARSING_FAILED; return ESP_FAIL; } return ESP_OK; } static esp_err_t pause_parsing(http_parser *parser, const char* at) { parser_data_t *parser_data = (parser_data_t *) parser->data; struct httpd_req *r = parser_data->req; struct httpd_req_aux *ra = r->aux; /* The length of data that was not parsed due to interruption * and hence needs to be read again later for parsing */ ssize_t unparsed = parser_data->raw_datalen - (at - ra->scratch); if (unparsed < 0) { ESP_LOGE(TAG, LOG_FMT("parsing beyond valid data = %d"), -unparsed); return ESP_ERR_INVALID_STATE; } /* Push back the un-parsed data into pending buffer for * receiving again with httpd_recv_with_opt() later when * read_block() executes */ if (unparsed && (unparsed != httpd_unrecv(r, at, unparsed))) { ESP_LOGE(TAG, LOG_FMT("data too large for un-recv = %d"), unparsed); return ESP_FAIL; } /* Signal http_parser to pause execution and save the maximum * possible length, of the yet un-parsed data, that may get * parsed before http_parser_execute() returns. This pre_parsed * length will be updated then to reflect the actual length * that got parsed, and must be skipped when parsing resumes */ parser_data->pre_parsed = unparsed; http_parser_pause(parser, 1); parser_data->paused = true; ESP_LOGD(TAG, LOG_FMT("paused")); return ESP_OK; } static size_t continue_parsing(http_parser *parser, size_t length) { parser_data_t *data = (parser_data_t *) parser->data; /* Part of the received data may have been parsed earlier * so we must skip that before parsing resumes */ length = MIN(length, data->pre_parsed); data->pre_parsed -= length; ESP_LOGD(TAG, LOG_FMT("skip pre-parsed data of size = %d"), length); http_parser_pause(parser, 0); data->paused = false; ESP_LOGD(TAG, LOG_FMT("un-paused")); return length; } /* http_parser callback on header field in HTTP request * May be invoked ATLEAST once every header field */ static esp_err_t cb_header_field(http_parser *parser, const char *at, size_t length) { parser_data_t *parser_data = (parser_data_t *) parser->data; struct httpd_req *r = parser_data->req; struct httpd_req_aux *ra = r->aux; /* Check previous status */ if (parser_data->status == PARSING_URL) { if (verify_url(parser) != ESP_OK) { /* verify_url would already have set the * error field of parser data, so only setting * status to failed */ parser_data->status = PARSING_FAILED; return ESP_FAIL; } ESP_LOGD(TAG, LOG_FMT("headers begin")); /* Last at is set to start of scratch where headers * will be received next */ parser_data->last.at = ra->scratch; parser_data->last.length = 0; parser_data->status = PARSING_HDR_FIELD; /* Stop parsing for now and give control to process */ if (pause_parsing(parser, at) != ESP_OK) { parser_data->error = HTTPD_500_INTERNAL_SERVER_ERROR; parser_data->status = PARSING_FAILED; return ESP_FAIL; } } else if (parser_data->status == PARSING_HDR_VALUE) { /* Overwrite terminator (CRLFs) following last header * (key: value) pair with null characters */ char *term_start = (char *)parser_data->last.at + parser_data->last.length; memset(term_start, '\0', at - term_start); /* Store current values of the parser callback arguments */ parser_data->last.at = at; parser_data->last.length = 0; parser_data->status = PARSING_HDR_FIELD; /* Increment header count */ ra->req_hdrs_count++; } else if (parser_data->status != PARSING_HDR_FIELD) { ESP_LOGE(TAG, LOG_FMT("unexpected state transition")); parser_data->error = HTTPD_500_INTERNAL_SERVER_ERROR; parser_data->status = PARSING_FAILED; return ESP_FAIL; } ESP_LOGD(TAG, LOG_FMT("processing field = %.*s"), length, at); /* Update length of header string */ parser_data->last.length += length; return ESP_OK; } /* http_parser callback on header value in HTTP request. * May be invoked ATLEAST once every header value */ static esp_err_t cb_header_value(http_parser *parser, const char *at, size_t length) { parser_data_t *parser_data = (parser_data_t *) parser->data; /* Check previous status */ if (parser_data->status == PARSING_HDR_FIELD) { /* Store current values of the parser callback arguments */ parser_data->last.at = at; parser_data->last.length = 0; parser_data->status = PARSING_HDR_VALUE; if (length == 0) { /* As per behavior of http_parser, when length > 0, * `at` points to the start of CRLF. But, in the * case when header value is empty (zero length), * then `at` points to the position right after * the CRLF. Since for our purpose we need `last.at` * to point to exactly where the CRLF starts, it * needs to be adjusted by the right offset */ char *at_adj = (char *)parser_data->last.at; /* Find the end of header field string */ while (*(--at_adj) != ':'); /* Now skip leading spaces' */ while (*(++at_adj) == ' '); /* Now we are at the right position */ parser_data->last.at = at_adj; } } else if (parser_data->status != PARSING_HDR_VALUE) { ESP_LOGE(TAG, LOG_FMT("unexpected state transition")); parser_data->error = HTTPD_500_INTERNAL_SERVER_ERROR; parser_data->status = PARSING_FAILED; return ESP_FAIL; } ESP_LOGD(TAG, LOG_FMT("processing value = %.*s"), length, at); /* Update length of header string */ parser_data->last.length += length; return ESP_OK; } /* http_parser callback on completing headers in HTTP request. * Will be invoked ONLY once every packet */ static esp_err_t cb_headers_complete(http_parser *parser) { parser_data_t *parser_data = (parser_data_t *) parser->data; struct httpd_req *r = parser_data->req; struct httpd_req_aux *ra = r->aux; /* Check previous status */ if (parser_data->status == PARSING_URL) { ESP_LOGD(TAG, LOG_FMT("no headers")); if (verify_url(parser) != ESP_OK) { /* verify_url would already have set the * error field of parser data, so only setting * status to failed */ parser_data->status = PARSING_FAILED; return ESP_FAIL; } } else if (parser_data->status == PARSING_HDR_VALUE) { /* Locate end of last header */ char *at = (char *)parser_data->last.at + parser_data->last.length; /* Check if there is data left to parse. This value should * at least be equal to the number of line terminators, i.e. 2 */ ssize_t remaining_length = parser_data->raw_datalen - (at - ra->scratch); if (remaining_length < 2) { ESP_LOGE(TAG, LOG_FMT("invalid length of data remaining to be parsed")); parser_data->error = HTTPD_500_INTERNAL_SERVER_ERROR; parser_data->status = PARSING_FAILED; return ESP_FAIL; } /* Locate end of headers section by skipping the remaining * two line terminators. No assumption is made here about the * termination sequence used apart from the necessity that it * must end with an LF, because: * 1) some clients may send non standard LFs instead of * CRLFs for indicating termination. * 2) it is the responsibility of http_parser to check * that the termination is either CRLF or LF and * not any other sequence */ unsigned short remaining_terminators = 2; while (remaining_length-- && remaining_terminators) { if (*at == '\n') { remaining_terminators--; } /* Overwrite termination characters with null */ *(at++) = '\0'; } if (remaining_terminators) { ESP_LOGE(TAG, LOG_FMT("incomplete termination of headers")); parser_data->error = HTTPD_400_BAD_REQUEST; parser_data->status = PARSING_FAILED; return ESP_FAIL; } /* Place the parser ptr right after the end of headers section */ parser_data->last.at = at; /* Increment header count */ ra->req_hdrs_count++; } else { ESP_LOGE(TAG, LOG_FMT("unexpected state transition")); parser_data->error = HTTPD_500_INTERNAL_SERVER_ERROR; parser_data->status = PARSING_FAILED; return ESP_FAIL; } /* In absence of body/chunked encoding, http_parser sets content_len to -1 */ r->content_len = ((int)parser->content_length != -1 ? parser->content_length : 0); ESP_LOGD(TAG, LOG_FMT("bytes read = %d"), parser->nread); ESP_LOGD(TAG, LOG_FMT("content length = %zu"), r->content_len); if (parser->upgrade) { ESP_LOGW(TAG, LOG_FMT("upgrade from HTTP not supported")); /* There is no specific HTTP error code to notify the client that * upgrade is not supported, thus sending 400 Bad Request */ parser_data->error = HTTPD_400_BAD_REQUEST; parser_data->status = PARSING_FAILED; return ESP_FAIL; } parser_data->status = PARSING_BODY; ra->remaining_len = r->content_len; return ESP_OK; } /* Last http_parser callback if body present in HTTP request. * Will be invoked ONLY once every packet */ static esp_err_t cb_on_body(http_parser *parser, const char *at, size_t length) { parser_data_t *parser_data = (parser_data_t *) parser->data; /* Check previous status */ if (parser_data->status != PARSING_BODY) { ESP_LOGE(TAG, LOG_FMT("unexpected state transition")); parser_data->error = HTTPD_500_INTERNAL_SERVER_ERROR; parser_data->status = PARSING_FAILED; return ESP_FAIL; } /* Pause parsing so that if part of another packet * is in queue then it doesn't get parsed, which * may reset the parser state and cause current * request packet to be lost */ if (pause_parsing(parser, at) != ESP_OK) { parser_data->error = HTTPD_500_INTERNAL_SERVER_ERROR; parser_data->status = PARSING_FAILED; return ESP_FAIL; } parser_data->last.at = 0; parser_data->last.length = 0; parser_data->status = PARSING_COMPLETE; ESP_LOGD(TAG, LOG_FMT("body begins")); return ESP_OK; } /* Last http_parser callback if body absent in HTTP request. * Will be invoked ONLY once every packet */ static esp_err_t cb_no_body(http_parser *parser) { parser_data_t *parser_data = (parser_data_t *) parser->data; /* Check previous status */ if (parser_data->status == PARSING_URL) { ESP_LOGD(TAG, LOG_FMT("no headers")); if (verify_url(parser) != ESP_OK) { /* verify_url would already have set the * error field of parser data, so only setting * status to failed */ parser_data->status = PARSING_FAILED; return ESP_FAIL; } } else if (parser_data->status != PARSING_BODY) { ESP_LOGE(TAG, LOG_FMT("unexpected state transition")); parser_data->error = HTTPD_500_INTERNAL_SERVER_ERROR; parser_data->status = PARSING_FAILED; return ESP_FAIL; } /* Pause parsing so that if part of another packet * is in queue then it doesn't get parsed, which * may reset the parser state and cause current * request packet to be lost */ if (pause_parsing(parser, parser_data->last.at) != ESP_OK) { parser_data->error = HTTPD_500_INTERNAL_SERVER_ERROR; parser_data->status = PARSING_FAILED; return ESP_FAIL; } parser_data->last.at = 0; parser_data->last.length = 0; parser_data->status = PARSING_COMPLETE; ESP_LOGD(TAG, LOG_FMT("message complete")); return ESP_OK; } static int read_block(httpd_req_t *req, size_t offset, size_t length) { struct httpd_req_aux *raux = req->aux; /* Limits the read to scratch buffer size */ ssize_t buf_len = MIN(length, (sizeof(raux->scratch) - offset)); if (buf_len <= 0) { return 0; } /* Receive data into buffer. If data is pending (from unrecv) then return * immediately after receiving pending data, as pending data may just complete * this request packet. */ int nbytes = httpd_recv_with_opt(req, raux->scratch + offset, buf_len, true); if (nbytes < 0) { ESP_LOGD(TAG, LOG_FMT("error in httpd_recv")); /* If timeout occurred allow the * situation to be handled */ if (nbytes == HTTPD_SOCK_ERR_TIMEOUT) { /* Invoke error handler which may return ESP_OK * to signal for retrying call to recv(), else it may * return ESP_FAIL to signal for closure of socket */ return (httpd_req_handle_err(req, HTTPD_408_REQ_TIMEOUT) == ESP_OK) ? HTTPD_SOCK_ERR_TIMEOUT : HTTPD_SOCK_ERR_FAIL; } /* Some socket error occurred. Return failure * to force closure of underlying socket. * Error message is not sent as socket may not * be valid anymore */ return HTTPD_SOCK_ERR_FAIL; } else if (nbytes == 0) { ESP_LOGD(TAG, LOG_FMT("connection closed")); /* Connection closed by client so no * need to send error response */ return HTTPD_SOCK_ERR_FAIL; } ESP_LOGD(TAG, LOG_FMT("received HTTP request block size = %d"), nbytes); return nbytes; } static int parse_block(http_parser *parser, size_t offset, size_t length) { parser_data_t *data = (parser_data_t *)(parser->data); httpd_req_t *req = data->req; struct httpd_req_aux *raux = req->aux; size_t nparsed = 0; if (!length) { /* Parsing is still happening but nothing to * parse means no more space left on buffer, * therefore it can be inferred that the * request URI/header must be too long */ ESP_LOGW(TAG, LOG_FMT("request URI/header too long")); switch (data->status) { case PARSING_URL: data->error = HTTPD_414_URI_TOO_LONG; break; case PARSING_HDR_FIELD: case PARSING_HDR_VALUE: data->error = HTTPD_431_REQ_HDR_FIELDS_TOO_LARGE; break; default: ESP_LOGE(TAG, LOG_FMT("unexpected state")); data->error = HTTPD_500_INTERNAL_SERVER_ERROR; break; } data->status = PARSING_FAILED; return -1; } /* Un-pause the parsing if paused */ if (data->paused) { nparsed = continue_parsing(parser, length); length -= nparsed; offset += nparsed; if (!length) { return nparsed; } } /* Execute http_parser */ nparsed = http_parser_execute(parser, &data->settings, raux->scratch + offset, length); /* Check state */ if (data->status == PARSING_FAILED) { /* It is expected that the error field of * parser data should have been set by now */ ESP_LOGW(TAG, LOG_FMT("parsing failed")); return -1; } else if (data->paused) { /* Update the value of pre_parsed which was set when * pause_parsing() was called. (length - nparsed) is * the length of the data that will need to be parsed * again later and hence must be deducted from the * pre_parsed length */ data->pre_parsed -= (length - nparsed); return 0; } else if (nparsed != length) { /* http_parser error */ data->error = HTTPD_400_BAD_REQUEST; data->status = PARSING_FAILED; ESP_LOGW(TAG, LOG_FMT("incomplete (%d/%d) with parser error = %d"), nparsed, length, parser->http_errno); return -1; } /* Return with the total length of the request packet * that has been parsed till now */ ESP_LOGD(TAG, LOG_FMT("parsed block size = %d"), offset + nparsed); return offset + nparsed; } static void parse_init(httpd_req_t *r, http_parser *parser, parser_data_t *data) { /* Initialize parser data */ memset(data, 0, sizeof(parser_data_t)); data->req = r; /* Initialize parser */ http_parser_init(parser, HTTP_REQUEST); parser->data = (void *)data; /* Initialize parser settings */ http_parser_settings_init(&data->settings); /* Set parser callbacks */ data->settings.on_url = cb_url; data->settings.on_header_field = cb_header_field; data->settings.on_header_value = cb_header_value; data->settings.on_headers_complete = cb_headers_complete; data->settings.on_body = cb_on_body; data->settings.on_message_complete = cb_no_body; } /* Function that receives TCP data and runs parser on it */ static esp_err_t httpd_parse_req(struct httpd_data *hd) { httpd_req_t *r = &hd->hd_req; int blk_len, offset; http_parser parser; parser_data_t parser_data; /* Initialize parser */ parse_init(r, &parser, &parser_data); /* Set offset to start of scratch buffer */ offset = 0; do { /* Read block into scratch buffer */ if ((blk_len = read_block(r, offset, PARSER_BLOCK_SIZE)) < 0) { if (blk_len == HTTPD_SOCK_ERR_TIMEOUT) { /* Retry read in case of non-fatal timeout error. * read_block() ensures that the timeout error is * handled properly so that this doesn't get stuck * in an infinite loop */ continue; } /* If not HTTPD_SOCK_ERR_TIMEOUT, returned error must * be HTTPD_SOCK_ERR_FAIL which means we need to return * failure and thereby close the underlying socket */ return ESP_FAIL; } /* This is used by the callbacks to track * data usage of the buffer */ parser_data.raw_datalen = blk_len + offset; /* Parse data block from buffer */ if ((offset = parse_block(&parser, offset, blk_len)) < 0) { /* HTTP error occurred. * Send error code as response status and * invoke error handler */ return httpd_req_handle_err(r, parser_data.error); } } while (parser_data.status != PARSING_COMPLETE); ESP_LOGD(TAG, LOG_FMT("parsing complete")); return httpd_uri(hd); } static void init_req(httpd_req_t *r, httpd_config_t *config) { r->handle = 0; r->method = 0; memset((char*)r->uri, 0, sizeof(r->uri)); r->content_len = 0; r->aux = 0; r->user_ctx = 0; r->sess_ctx = 0; r->free_ctx = 0; r->ignore_sess_ctx_changes = 0; } static void init_req_aux(struct httpd_req_aux *ra, httpd_config_t *config) { ra->sd = 0; memset(ra->scratch, 0, sizeof(ra->scratch)); ra->remaining_len = 0; ra->status = 0; ra->content_type = 0; ra->first_chunk_sent = 0; ra->req_hdrs_count = 0; ra->resp_hdrs_count = 0; memset(ra->resp_hdrs, 0, config->max_resp_headers * sizeof(struct resp_hdr)); } static void httpd_req_cleanup(httpd_req_t *r) { struct httpd_req_aux *ra = r->aux; /* Check if the context has changed and needs to be cleared */ if ((r->ignore_sess_ctx_changes == false) && (ra->sd->ctx != r->sess_ctx)) { httpd_sess_free_ctx(ra->sd->ctx, ra->sd->free_ctx); } /* Retrieve session info from the request into the socket database. */ ra->sd->ctx = r->sess_ctx; ra->sd->free_ctx = r->free_ctx; ra->sd->ignore_sess_ctx_changes = r->ignore_sess_ctx_changes; /* Clear out the request and request_aux structures */ ra->sd = NULL; r->handle = NULL; r->aux = NULL; } /* Function that processes incoming TCP data and * updates the http request data httpd_req_t */ esp_err_t httpd_req_new(struct httpd_data *hd, struct sock_db *sd) { httpd_req_t *r = &hd->hd_req; init_req(r, &hd->config); init_req_aux(&hd->hd_req_aux, &hd->config); r->handle = hd; r->aux = &hd->hd_req_aux; /* Associate the request to the socket */ struct httpd_req_aux *ra = r->aux; ra->sd = sd; /* Set defaults */ ra->status = (char *)HTTPD_200; ra->content_type = (char *)HTTPD_TYPE_TEXT; ra->first_chunk_sent = false; /* Copy session info to the request */ r->sess_ctx = sd->ctx; r->free_ctx = sd->free_ctx; r->ignore_sess_ctx_changes = sd->ignore_sess_ctx_changes; /* Parse request */ esp_err_t err = httpd_parse_req(hd); if (err != ESP_OK) { httpd_req_cleanup(r); } return err; } /* Function that resets the http request data */ esp_err_t httpd_req_delete(struct httpd_data *hd) { httpd_req_t *r = &hd->hd_req; struct httpd_req_aux *ra = r->aux; /* Finish off reading any pending/leftover data */ while (ra->remaining_len) { /* Any length small enough not to overload the stack, but large * enough to finish off the buffers fast */ char dummy[CONFIG_HTTPD_PURGE_BUF_LEN]; int recv_len = MIN(sizeof(dummy), ra->remaining_len); recv_len = httpd_req_recv(r, dummy, recv_len); if (recv_len < 0) { httpd_req_cleanup(r); return ESP_FAIL; } ESP_LOGD(TAG, LOG_FMT("purging data size : %d bytes"), recv_len); #ifdef CONFIG_HTTPD_LOG_PURGE_DATA /* Enabling this will log discarded binary HTTP content data at * Debug level. For large content data this may not be desirable * as it will clutter the log */ ESP_LOGD(TAG, "================= PURGED DATA ================="); ESP_LOG_BUFFER_HEX_LEVEL(TAG, dummy, recv_len, ESP_LOG_DEBUG); ESP_LOGD(TAG, "==============================================="); #endif } httpd_req_cleanup(r); return ESP_OK; } /* Validates the request to prevent users from calling APIs, that are to * be called only inside URI handler, outside the handler context */ bool httpd_validate_req_ptr(httpd_req_t *r) { if (r) { struct httpd_data *hd = (struct httpd_data *) r->handle; if (hd) { /* Check if this function is running in the context of * the correct httpd server thread */ if (httpd_os_thread_handle() == hd->hd_td.handle) { return true; } } } return false; } /* Helper function to get a URL query tag from a query string of the type param1=val1¶m2=val2 */ esp_err_t httpd_query_key_value(const char *qry_str, const char *key, char *val, size_t val_size) { if (qry_str == NULL || key == NULL || val == NULL) { return ESP_ERR_INVALID_ARG; } const char *qry_ptr = qry_str; const size_t buf_len = val_size; while (strlen(qry_ptr)) { /* Search for the '=' character. Else, it would mean * that the parameter is invalid */ const char *val_ptr = strchr(qry_ptr, '='); if (!val_ptr) { break; } size_t offset = val_ptr - qry_ptr; /* If the key, does not match, continue searching. * Compare lengths first as key from url is not * null terminated (has '=' in the end) */ if ((offset != strlen(key)) || (strncasecmp(qry_ptr, key, offset))) { /* Get the name=val string. Multiple name=value pairs * are separated by '&' */ qry_ptr = strchr(val_ptr, '&'); if (!qry_ptr) { break; } qry_ptr++; continue; } /* Locate start of next query */ qry_ptr = strchr(++val_ptr, '&'); /* Or this could be the last query, in which * case get to the end of query string */ if (!qry_ptr) { qry_ptr = val_ptr + strlen(val_ptr); } /* Update value length, including one byte for null */ val_size = qry_ptr - val_ptr + 1; /* Copy value to the caller's buffer. */ strlcpy(val, val_ptr, MIN(val_size, buf_len)); /* If buffer length is smaller than needed, return truncation error */ if (buf_len < val_size) { return ESP_ERR_HTTPD_RESULT_TRUNC; } return ESP_OK; } ESP_LOGD(TAG, LOG_FMT("key %s not found"), key); return ESP_ERR_NOT_FOUND; } size_t httpd_req_get_url_query_len(httpd_req_t *r) { if (r == NULL) { return 0; } if (!httpd_valid_req(r)) { return 0; } struct httpd_req_aux *ra = r->aux; struct http_parser_url *res = &ra->url_parse_res; /* Check if query field is present in the URL */ if (res->field_set & (1 << UF_QUERY)) { return res->field_data[UF_QUERY].len; } return 0; } esp_err_t httpd_req_get_url_query_str(httpd_req_t *r, char *buf, size_t buf_len) { if (r == NULL || buf == NULL) { return ESP_ERR_INVALID_ARG; } if (!httpd_valid_req(r)) { return ESP_ERR_HTTPD_INVALID_REQ; } struct httpd_req_aux *ra = r->aux; struct http_parser_url *res = &ra->url_parse_res; /* Check if query field is present in the URL */ if (res->field_set & (1 << UF_QUERY)) { const char *qry = r->uri + res->field_data[UF_QUERY].off; /* Minimum required buffer len for keeping * null terminated query string */ size_t min_buf_len = res->field_data[UF_QUERY].len + 1; strlcpy(buf, qry, MIN(buf_len, min_buf_len)); if (buf_len < min_buf_len) { return ESP_ERR_HTTPD_RESULT_TRUNC; } return ESP_OK; } return ESP_ERR_NOT_FOUND; } /* Get the length of the value string of a header request field */ size_t httpd_req_get_hdr_value_len(httpd_req_t *r, const char *field) { if (r == NULL || field == NULL) { return 0; } if (!httpd_valid_req(r)) { return 0; } struct httpd_req_aux *ra = r->aux; const char *hdr_ptr = ra->scratch; /*!< Request headers are kept in scratch buffer */ unsigned count = ra->req_hdrs_count; /*!< Count set during parsing */ while (count--) { /* Search for the ':' character. Else, it would mean * that the field is invalid */ const char *val_ptr = strchr(hdr_ptr, ':'); if (!val_ptr) { break; } /* If the field, does not match, continue searching. * Compare lengths first as field from header is not * null terminated (has ':' in the end). */ if ((val_ptr - hdr_ptr != strlen(field)) || (strncasecmp(hdr_ptr, field, strlen(field)))) { if (count) { /* Jump to end of header field-value string */ hdr_ptr = 1 + strchr(hdr_ptr, '\0'); /* Skip all null characters (with which the line * terminators had been overwritten) */ while (*hdr_ptr == '\0') { hdr_ptr++; } } continue; } /* Skip ':' */ val_ptr++; /* Skip preceding space */ while ((*val_ptr != '\0') && (*val_ptr == ' ')) { val_ptr++; } return strlen(val_ptr); } return 0; } /* Get the value of a field from the request headers */ esp_err_t httpd_req_get_hdr_value_str(httpd_req_t *r, const char *field, char *val, size_t val_size) { if (r == NULL || field == NULL) { return ESP_ERR_INVALID_ARG; } if (!httpd_valid_req(r)) { return ESP_ERR_HTTPD_INVALID_REQ; } struct httpd_req_aux *ra = r->aux; const char *hdr_ptr = ra->scratch; /*!< Request headers are kept in scratch buffer */ unsigned count = ra->req_hdrs_count; /*!< Count set during parsing */ const size_t buf_len = val_size; while (count--) { /* Search for the ':' character. Else, it would mean * that the field is invalid */ const char *val_ptr = strchr(hdr_ptr, ':'); if (!val_ptr) { break; } /* If the field, does not match, continue searching. * Compare lengths first as field from header is not * null terminated (has ':' in the end). */ if ((val_ptr - hdr_ptr != strlen(field)) || (strncasecmp(hdr_ptr, field, strlen(field)))) { if (count) { /* Jump to end of header field-value string */ hdr_ptr = 1 + strchr(hdr_ptr, '\0'); /* Skip all null characters (with which the line * terminators had been overwritten) */ while (*hdr_ptr == '\0') { hdr_ptr++; } } continue; } /* Skip ':' */ val_ptr++; /* Skip preceding space */ while ((*val_ptr != '\0') && (*val_ptr == ' ')) { val_ptr++; } /* Get the NULL terminated value and copy it to the caller's buffer. */ strlcpy(val, val_ptr, buf_len); /* Update value length, including one byte for null */ val_size = strlen(val_ptr) + 1; /* If buffer length is smaller than needed, return truncation error */ if (buf_len < val_size) { return ESP_ERR_HTTPD_RESULT_TRUNC; } return ESP_OK; } return ESP_ERR_NOT_FOUND; }