http_protocol.h revision 2968569cc3b1440bdb874d2d597ea4a49f0c0acf
/* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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_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 or "", return NULL (do not set content-type).
* - 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);
/**
* 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);
/**
* 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 r->allowed_methods.
* @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 r->allowed_methods.
* @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 r->allowed_methods.
* @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 r->allowed_methods.
* @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);
/**
* 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);
/**
* Output a string for the current request
* @param str The string to output
* @param r The current request
* @return The number of bytes sent
* @note ap_rputs may be implemented as macro or inline function
*/
static APR_INLINE int ap_rputs(const char *str, request_rec *r)
{
return ap_rwrite(str, strlen(str), 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,...)
ap_func_attr_sentinel;
/**
* 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: <pre>
* 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.
* </pre>
* @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.
* @param r The current request
*/
AP_DECLARE(void) ap_note_auth_failure(request_rec *r);
/**
* @deprecated @see ap_note_auth_failure
*/
AP_DECLARE(void) ap_note_basic_auth_failure(request_rec *r);
/**
* @deprecated @see ap_note_auth_failure
*/
AP_DECLARE(void) ap_note_digest_auth_failure(request_rec *r);
/**
* This hook allows modules to add support for a specific auth type to
* ap_note_auth_failure
* @param r the current request
* @param auth_type the configured auth_type
* @return OK, DECLINED
*/
AP_DECLARE_HOOK(int, note_auth_failure, (request_rec *r, const char *auth_type))
/**
* 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 */
/*
* pre_read_request --- run right before read_request_line(),
* and not run during any subrequests.
*/
/**
* This hook allows modules to affect the request or connection immediately before
* the request has been read, and before any other phases have been processes.
* @param r The current request of the soon-to-be-read request
* @param c The connection
* @return None/void
*/
AP_DECLARE_HOOK(void,pre_read_request,(request_rec *r, conn_rec *c))
/*
* 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);
/**
* Send an interim (HTTP 1xx) response immediately.
* @param r The request
* @param send_headers Whether to send&clear headers in r->headers_out
*/
AP_DECLARE(void) ap_send_interim_response(request_rec *r, int send_headers);
#ifdef __cplusplus
}
#endif
#endif /* !APACHE_HTTP_PROTOCOL_H */
/** @} */