/* Copyright 1999-2005 The Apache Software Foundation or its licensors, as * applicable. * * 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. */ /** * @file http_protocol.h * @brief HTTP protocol handling * * @defgroup APACHE_CORE_PROTO HTTP Protocol Handling * @ingroup APACHE_CORE * @{ */ #ifndef APACHE_HTTP_PROTOCOL_H #define APACHE_HTTP_PROTOCOL_H #include "httpd.h" #include "apr_hooks.h" #include "apr_portable.h" #include "apr_mmap.h" #include "apr_buckets.h" #include "util_filter.h" #ifdef __cplusplus extern "C" { #endif /** * This hook allows modules to insert filters for the current error response * @param r the current request * @ingroup hooks */ AP_DECLARE_HOOK(void,insert_error_filter,(request_rec *r)) /** This is an optimization. We keep a record of the filter_rec that * stores the old_write filter, so that we can avoid strcmp's later. */ AP_DECLARE_DATA extern ap_filter_rec_t *ap_old_write_func; /* * Prototypes for routines which either talk directly back to the user, * or control the ones that eventually do. */ /** * Read a request and fill in the fields. * @param c The current connection * @return The new request_rec */ request_rec *ap_read_request(conn_rec *c); /** * Read the mime-encoded headers. * @param r The current request */ AP_DECLARE(void) ap_get_mime_headers(request_rec *r); /** * Optimized version of ap_get_mime_headers() that requires a * temporary brigade to work with * @param r The current request * @param bb temp brigade */ AP_DECLARE(void) ap_get_mime_headers_core(request_rec *r, apr_bucket_brigade *bb); /* Finish up stuff after a request */ /** * Called at completion of sending the response. It sends the terminating * protocol information. * @param r The current request */ AP_DECLARE(void) ap_finalize_request_protocol(request_rec *r); /** * Send error back to client. * @param r The current request * @param recursive_error last arg indicates error status in case we get * an error in the process of trying to deal with an ErrorDocument * to handle some other error. In that case, we print the default * report for the first thing that went wrong, and more briefly report * on the problem with the ErrorDocument. */ AP_DECLARE(void) ap_send_error_response(request_rec *r, int recursive_error); /* Set last modified header line from the lastmod date of the associated file. * Also, set content length. * * May return an error status, typically HTTP_NOT_MODIFIED (that when the * permit_cache argument is set to one). */ /** * Set the content length for this request * @param r The current request * @param length The new content length */ AP_DECLARE(void) ap_set_content_length(request_rec *r, apr_off_t length); /** * Set the keepalive status for this request * @param r The current request * @return 1 if keepalive can be set, 0 otherwise */ AP_DECLARE(int) ap_set_keepalive(request_rec *r); /** * Return the latest rational time from a request/mtime pair. Mtime is * returned unless it's in the future, in which case we return the current time. * @param r The current request * @param mtime The last modified time * @return the latest rational time. */ AP_DECLARE(apr_time_t) ap_rationalize_mtime(request_rec *r, apr_time_t mtime); /** * Build the content-type that should be sent to the client from the * content-type specified. The following rules are followed: * - if type is NULL, type is set to ap_default_type(r) * - if charset adding is disabled, stop processing and return type. * - then, if there are no parameters on type, add the default charset * - return type * @param r The current request * @param type The content type * @return The content-type */ AP_DECLARE(const char *) ap_make_content_type(request_rec *r, const char *type); #ifdef CORE_PRIVATE /** * Precompile metadata structures used by ap_make_content_type() * @param pool The pool to use for allocations */ AP_DECLARE(void) ap_setup_make_content_type(apr_pool_t *pool); #endif /* CORE_PRIVATE */ /** * Construct an entity tag from the resource information. If it's a real * file, build in some of the file characteristics. * @param r The current request * @param force_weak Force the entity tag to be weak - it could be modified * again in as short an interval. * @return The entity tag */ AP_DECLARE(char *) ap_make_etag(request_rec *r, int force_weak); /** * Set the E-tag outgoing header * @param r The current request */ AP_DECLARE(void) ap_set_etag(request_rec *r); /** * Set the last modified time for the file being sent * @param r The current request */ AP_DECLARE(void) ap_set_last_modified(request_rec *r); /** * Implements condition GET rules for HTTP/1.1 specification. This function * inspects the client headers and determines if the response fulfills * the requirements specified. * @param r The current request * @return OK if the response fulfills the condition GET rules, some * other status code otherwise */ AP_DECLARE(int) ap_meets_conditions(request_rec *r); /* Other ways to send stuff at the client. All of these keep track * of bytes_sent automatically. This indirection is intended to make * it a little more painless to slide things like HTTP-NG packetization * underneath the main body of the code later. In the meantime, it lets * us centralize a bit of accounting (bytes_sent). * * These also return the number of bytes written by the call. * They should only be called with a timeout registered, for obvious reaasons. * (Ditto the send_header stuff). */ /** * Send an entire file to the client, using sendfile if supported by the * current platform * @param fd The file to send. * @param r The current request * @param offset Offset into the file to start sending. * @param length Amount of data to send * @param nbytes Amount of data actually sent */ AP_DECLARE(apr_status_t) ap_send_fd(apr_file_t *fd, request_rec *r, apr_off_t offset, apr_size_t length, apr_size_t *nbytes); #if APR_HAS_MMAP /** * Send an MMAP'ed file to the client * @param mm The MMAP'ed file to send * @param r The current request * @param offset The offset into the MMAP to start sending * @param length The amount of data to send * @return The number of bytes sent */ AP_DECLARE(size_t) ap_send_mmap(apr_mmap_t *mm, request_rec *r, size_t offset, size_t length); #endif /** * Register a new request method, and return the offset that will be * associated with that method. * * @param p The pool to create registered method numbers from. * @param methname The name of the new method to register. * @return Ab int value representing an offset into a bitmask. */ AP_DECLARE(int) ap_method_register(apr_pool_t *p, const char *methname); /** * Initialize the method_registry and allocate memory for it. * * @param p Pool to allocate memory for the registry from. */ AP_DECLARE(void) ap_method_registry_init(apr_pool_t *p); /** * This is a convenience macro to ease with checking a mask * against a method name. */ #define AP_METHOD_CHECK_ALLOWED(mask, methname) \ ((mask) & (AP_METHOD_BIT << ap_method_number_of((methname)))) /** * Create a new method list with the specified number of preallocated * slots for extension methods. * * @param p Pointer to a pool in which the structure should be * allocated. * @param nelts Number of preallocated extension slots * @return Pointer to the newly created structure. */ AP_DECLARE(ap_method_list_t *) ap_make_method_list(apr_pool_t *p, int nelts); /** * Copy a method list * * @param dest List to copy to * @param src List to copy from */ AP_DECLARE(void) ap_copy_method_list(ap_method_list_t *dest, ap_method_list_t *src); /** * Search for an HTTP method name in an ap_method_list_t structure, and * return true if found. * * @param method String containing the name of the method to check. * @param l Pointer to a method list, such as cmd->methods_limited. * @return 1 if method is in the list, otherwise 0 */ AP_DECLARE(int) ap_method_in_list(ap_method_list_t *l, const char *method); /** * Add an HTTP method name to an ap_method_list_t structure if it isn't * already listed. * * @param method String containing the name of the method to check. * @param l Pointer to a method list, such as cmd->methods_limited. * @return None. */ AP_DECLARE(void) ap_method_list_add(ap_method_list_t *l, const char *method); /** * Remove an HTTP method name from an ap_method_list_t structure. * * @param l Pointer to a method list, such as cmd->methods_limited. * @param method String containing the name of the method to remove. * @return None. */ AP_DECLARE(void) ap_method_list_remove(ap_method_list_t *l, const char *method); /** * Reset a method list to be completely empty. * * @param l Pointer to a method list, such as cmd->methods_limited. * @return None. */ AP_DECLARE(void) ap_clear_method_list(ap_method_list_t *l); /** * Set the content type for this request (r->content_type). * @param r The current request * @param ct The new content type * @warning This function must be called to set r->content_type in order * for the AddOutputFilterByType directive to work correctly. */ AP_DECLARE(void) ap_set_content_type(request_rec *r, const char *ct); /* Hmmm... could macrofy these for now, and maybe forever, though the * definitions of the macros would get a whole lot hairier. */ /** * Output one character for this request * @param c the character to output * @param r the current request * @return The number of bytes sent */ AP_DECLARE(int) ap_rputc(int c, request_rec *r); /** * Output a string for the current request * @param str The string to output * @param r The current request * @return The number of bytes sent */ AP_DECLARE(int) ap_rputs(const char *str, request_rec *r); /** * Write a buffer for the current request * @param buf The buffer to write * @param nbyte The number of bytes to send from the buffer * @param r The current request * @return The number of bytes sent */ AP_DECLARE(int) ap_rwrite(const void *buf, int nbyte, request_rec *r); /** * Write an unspecified number of strings to the request * @param r The current request * @param ... The strings to write * @return The number of bytes sent */ AP_DECLARE_NONSTD(int) ap_rvputs(request_rec *r,...); /** * Output data to the client in a printf format * @param r The current request * @param fmt The format string * @param vlist The arguments to use to fill out the format string * @return The number of bytes sent */ AP_DECLARE(int) ap_vrprintf(request_rec *r, const char *fmt, va_list vlist); /** * Output data to the client in a printf format * @param r The current request * @param fmt The format string * @param ... The arguments to use to fill out the format string * @return The number of bytes sent */ AP_DECLARE_NONSTD(int) ap_rprintf(request_rec *r, const char *fmt,...) __attribute__((format(printf,2,3))); /** * Flush all of the data for the current request to the client * @param r The current request * @return The number of bytes sent */ AP_DECLARE(int) ap_rflush(request_rec *r); /** * Index used in custom_responses array for a specific error code * (only use outside protocol.c is in getting them configured). * @param status HTTP status code * @return The index of the response */ AP_DECLARE(int) ap_index_of_response(int status); /** * Return the Status-Line for a given status code (excluding the * HTTP-Version field). If an invalid or unknown status code is * passed, "500 Internal Server Error" will be returned. * @param status The HTTP status code * @return The Status-Line */ AP_DECLARE(const char *) ap_get_status_line(int status); /* Reading a block of data from the client connection (e.g., POST arg) */ /** * Setup the client to allow Apache to read the request body. * @param r The current request * @param read_policy How the server should interpret a chunked * transfer-encoding. One of: 
 *    REQUEST_NO_BODY          Send 413 error if message has any body
 *    REQUEST_CHUNKED_ERROR    Send 411 error if body without Content-Length
 *    REQUEST_CHUNKED_DECHUNK  If chunked, remove the chunks for me.
 *
* @return either OK or an error code */ AP_DECLARE(int) ap_setup_client_block(request_rec *r, int read_policy); /** * Determine if the client has sent any data. This also sends a * 100 Continue response to HTTP/1.1 clients, so modules should not be called * until the module is ready to read content. * @warning Never call this function more than once. * @param r The current request * @return 0 if there is no message to read, 1 otherwise */ AP_DECLARE(int) ap_should_client_block(request_rec *r); /** * Call this in a loop. It will put data into a buffer and return the length * of the input block * @param r The current request * @param buffer The buffer in which to store the data * @param bufsiz The size of the buffer * @return Number of bytes inserted into the buffer. When done reading, 0 * if EOF, or -1 if there was an error */ AP_DECLARE(long) ap_get_client_block(request_rec *r, char *buffer, apr_size_t bufsiz); /** * In HTTP/1.1, any method can have a body. However, most GET handlers * wouldn't know what to do with a request body if they received one. * This helper routine tests for and reads any message body in the request, * simply discarding whatever it receives. We need to do this because * failing to read the request body would cause it to be interpreted * as the next request on a persistent connection. * @param r The current request * @return error status if request is malformed, OK otherwise */ AP_DECLARE(int) ap_discard_request_body(request_rec *r); /** * Setup the output headers so that the client knows how to authenticate * itself the next time, if an authentication request failed. This function * works for both basic and digest authentication * @param r The current request */ AP_DECLARE(void) ap_note_auth_failure(request_rec *r); /** * Setup the output headers so that the client knows how to authenticate * itself the next time, if an authentication request failed. This function * works only for basic authentication * @param r The current request */ AP_DECLARE(void) ap_note_basic_auth_failure(request_rec *r); /** * Setup the output headers so that the client knows how to authenticate * itself the next time, if an authentication request failed. This function * works only for digest authentication * @param r The current request */ AP_DECLARE(void) ap_note_digest_auth_failure(request_rec *r); /** * Get the password from the request headers * @param r The current request * @param pw The password as set in the headers * @return 0 (OK) if it set the 'pw' argument (and assured * a correct value in r->user); otherwise it returns * an error code, either HTTP_INTERNAL_SERVER_ERROR if things are * really confused, HTTP_UNAUTHORIZED if no authentication at all * seemed to be in use, or DECLINED if there was authentication but * it wasn't Basic (in which case, the caller should presumably * decline as well). */ AP_DECLARE(int) ap_get_basic_auth_pw(request_rec *r, const char **pw); /** * parse_uri: break apart the uri * @warning Side Effects: * @li sets r->args to rest after '?' (or NULL if no '?') * @li sets r->uri to request uri (without r->args part) * @li sets r->hostname (if not set already) from request (scheme://host:port) * @param r The current request * @param uri The uri to break apart */ AP_CORE_DECLARE(void) ap_parse_uri(request_rec *r, const char *uri); /** * Get the next line of input for the request * @param s The buffer into which to read the line * @param n The size of the buffer * @param r The request * @param fold Whether to merge continuation lines * @return The length of the line, if successful * n, if the line is too big to fit in the buffer * -1 for miscellaneous errors */ AP_DECLARE(int) ap_getline(char *s, int n, request_rec *r, int fold); /** * Get the next line of input for the request * * Note: on ASCII boxes, ap_rgetline is a macro which simply calls * ap_rgetline_core to get the line of input. * * on EBCDIC boxes, ap_rgetline is a wrapper function which * translates ASCII protocol lines to the local EBCDIC code page * after getting the line of input. * * @param s Pointer to the pointer to the buffer into which the line * should be read; if *s==NULL, a buffer of the necessary size * to hold the data will be allocated from the request pool * @param n The size of the buffer * @param read The length of the line. * @param r The request * @param fold Whether to merge continuation lines * @param bb Working brigade to use when reading buckets * @return APR_SUCCESS, if successful * APR_ENOSPC, if the line is too big to fit in the buffer * Other errors where appropriate */ #if APR_CHARSET_EBCDIC AP_DECLARE(apr_status_t) ap_rgetline(char **s, apr_size_t n, apr_size_t *read, request_rec *r, int fold, apr_bucket_brigade *bb); #else /* ASCII box */ #define ap_rgetline(s, n, read, r, fold, bb) \ ap_rgetline_core((s), (n), (read), (r), (fold), (bb)) #endif /** @see ap_rgetline */ AP_DECLARE(apr_status_t) ap_rgetline_core(char **s, apr_size_t n, apr_size_t *read, request_rec *r, int fold, apr_bucket_brigade *bb); /** * Get the method number associated with the given string, assumed to * contain an HTTP method. Returns M_INVALID if not recognized. * @param method A string containing a valid HTTP method * @return The method number */ AP_DECLARE(int) ap_method_number_of(const char *method); /** * Get the method name associated with the given internal method * number. Returns NULL if not recognized. * @param p A pool to use for temporary allocations. * @param methnum An integer value corresponding to an internal method number * @return The name corresponding to the method number */ AP_DECLARE(const char *) ap_method_name_of(apr_pool_t *p, int methnum); /* Hooks */ /* * post_read_request --- run right after read_request or internal_redirect, * and not run during any subrequests. */ /** * This hook allows modules to affect the request immediately after the request * has been read, and before any other phases have been processes. This allows * modules to make decisions based upon the input header fields * @param r The current request * @return OK or DECLINED */ AP_DECLARE_HOOK(int,post_read_request,(request_rec *r)) /** * This hook allows modules to perform any module-specific logging activities * over and above the normal server things. * @param r The current request * @return OK, DECLINED, or HTTP_... */ AP_DECLARE_HOOK(int,log_transaction,(request_rec *r)) /** * This hook allows modules to retrieve the http scheme for a request. This * allows Apache modules to easily extend the schemes that Apache understands * @param r The current request * @return The http scheme from the request */ AP_DECLARE_HOOK(const char *,http_scheme,(const request_rec *r)) /** * Return the default port from the current request * @param r The current request * @return The current port */ AP_DECLARE_HOOK(apr_port_t,default_port,(const request_rec *r)) /** @see ap_bucket_type_error */ typedef struct ap_bucket_error ap_bucket_error; /** * @struct ap_bucket_error * @brief A bucket referring to an HTTP error * * This bucket can be passed down the filter stack to indicate that an * HTTP error occurred while running a filter. In order for this bucket * to be used successfully, it MUST be sent as the first bucket in the * first brigade to be sent from a given filter. */ struct ap_bucket_error { /** Number of buckets using this memory */ apr_bucket_refcount refcount; /** The error code */ int status; /** The error string */ const char *data; }; /** @see ap_bucket_type_error */ AP_DECLARE_DATA extern const apr_bucket_type_t ap_bucket_type_error; /** * Determine if a bucket is an error bucket * @param e The bucket to inspect * @return true or false */ #define AP_BUCKET_IS_ERROR(e) (e->type == &ap_bucket_type_error) /** * Make the bucket passed in an error bucket * @param b The bucket to make into an error bucket * @param error The HTTP error code to put in the bucket. * @param buf An optional error string to put in the bucket. * @param p A pool to allocate out of. * @return The new bucket, or NULL if allocation failed */ AP_DECLARE(apr_bucket *) ap_bucket_error_make(apr_bucket *b, int error, const char *buf, apr_pool_t *p); /** * Create a bucket referring to an HTTP error. * @param error The HTTP error code to put in the bucket. * @param buf An optional error string to put in the bucket. * @param p A pool to allocate the error string out of. * @param list The bucket allocator from which to allocate the bucket * @return The new bucket, or NULL if allocation failed */ AP_DECLARE(apr_bucket *) ap_bucket_error_create(int error, const char *buf, apr_pool_t *p, apr_bucket_alloc_t *list); AP_DECLARE_NONSTD(apr_status_t) ap_byterange_filter(ap_filter_t *f, apr_bucket_brigade *b); AP_DECLARE_NONSTD(apr_status_t) ap_http_header_filter(ap_filter_t *f, apr_bucket_brigade *b); AP_DECLARE_NONSTD(apr_status_t) ap_content_length_filter(ap_filter_t *, apr_bucket_brigade *); AP_DECLARE_NONSTD(apr_status_t) ap_old_write_filter(ap_filter_t *f, apr_bucket_brigade *b); /** * Sett up the protocol fields for subsidiary requests * @param rnew New Sub Request * @param r current request */ AP_DECLARE(void) ap_set_sub_req_protocol(request_rec *rnew, const request_rec *r); /** * A wrapup function to keep the internal accounting straight. * Indicates that there is no more content coming. * @param sub_r Subrequest that is now compete */ AP_DECLARE(void) ap_finalize_sub_req_protocol(request_rec *sub_r); #ifdef __cplusplus } #endif #endif /* !APACHE_HTTP_PROTOCOL_H */ /** @} */