| /* |
| * include/types/filteers.h |
| * This file defines everything related to stream filters. |
| * |
| * Copyright (C) 2015 Qualys Inc., Christopher Faulet <cfaulet@qualys.com> |
| * |
| * This library is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU Lesser General Public |
| * License as published by the Free Software Foundation, version 2.1 |
| * exclusively. |
| * |
| * This library is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * Lesser General Public License for more details. |
| * |
| * You should have received a copy of the GNU Lesser General Public |
| * License along with this library; if not, write to the Free Software |
| * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| */ |
| #ifndef _TYPES_FILTERS_H |
| #define _TYPES_FILTERS_H |
| |
| #include <common/config.h> |
| #include <common/mini-clist.h> |
| |
| struct http_msg; |
| struct proxy; |
| struct stream; |
| struct channel; |
| struct flt_conf; |
| struct filter; |
| |
| /* Descriptor for a "filter" keyword. The ->parse() function returns 0 in case |
| * of success, or a combination of ERR_* flags if an error is encountered. The |
| * function pointer can be NULL if not implemented. |
| */ |
| struct flt_kw { |
| const char *kw; |
| int (*parse)(char **args, int *cur_arg, struct proxy *px, |
| struct flt_conf *fconf, char **err, void *private); |
| void *private; |
| }; |
| |
| /* |
| * A keyword list. It is a NULL-terminated array of keywords. It embeds a struct |
| * list in order to be linked to other lists, allowing it to easily be declared |
| * where it is needed, and linked without duplicating data nor allocating |
| * memory. It is also possible to indicate a scope for the keywords. |
| */ |
| struct flt_kw_list { |
| const char *scope; |
| struct list list; |
| struct flt_kw kw[VAR_ARRAY]; |
| }; |
| |
| /* |
| * Callbacks available on a filter: |
| * |
| * - init : Initializes the filter for a proxy. Returns a |
| * negative value if an error occurs. |
| * - deinit : Cleans up what the init function has done. |
| * - check : Check the filter config for a proxy. Returns the |
| * number of errors encountered. |
| * - init_per_thread : Initializes the filter for a proxy for a specific |
| * thread. Returns a negative value if an error |
| * occurs. |
| * - deinit_per_thread : Cleans up what the init_per_thread funcion has |
| * done. |
| * |
| * |
| * - attach : Called after a filter instance creation, when it is |
| * attached to a stream. This happens when the stream |
| * is started for filters defined on the stream's |
| * frontend and when the backend is set for filters |
| * declared on the stream's backend. |
| * Returns a negative value if an error occurs, 0 if |
| * the filter must be ignored for the stream, any other |
| * value otherwise. |
| * - stream_start : Called when a stream is started. This callback will |
| * only be called for filters defined on the stream's |
| * frontend. |
| * Returns a negative value if an error occurs, any |
| * other value otherwise. |
| * - stream_set_backend : Called when a backend is set for a stream. This |
| * callbacks will be called for all filters attached |
| * to a stream (frontend and backend). |
| * Returns a negative value if an error occurs, any |
| * other value otherwise. |
| * - stream_stop : Called when a stream is stopped. This callback will |
| * only be called for filters defined on the stream's |
| * frontend. |
| * - detach : Called when a filter instance is detached from a |
| * stream, before its destruction. This happens when |
| * the stream is stopped for filters defined on the |
| * stream's frontend and when the analyze ends for |
| * filters defined on the stream's backend. |
| * - check_timeouts : Called when a a stream is woken up because of an |
| * expired timer. |
| * |
| * |
| * - channel_start_analyze: Called when a filter starts to analyze a channel. |
| * Returns a negative value if an error occurs, 0 if |
| * it needs to wait, any other value otherwise. |
| * - channel_pre_analyze : Called before each analyzer attached to a channel, |
| * expects analyzers responsible for data sending. |
| * Returns a negative value if an error occurs, 0 if |
| * it needs to wait, any other value otherwise. |
| * - channel_post_analyze: Called after each analyzer attached to a channel, |
| * expects analyzers responsible for data sending. |
| * Returns a negative value if an error occurs, |
| * any other value otherwise. |
| * - channel_end_analyze : Called when all other analyzers have finished their |
| * processing. |
| * Returns a negative value if an error occurs, 0 if |
| * it needs to wait, any other value otherwise. |
| * |
| * |
| * - http_headers : Called before the body parsing, after all HTTP |
| * headers was parsed and analyzed. |
| * Returns a negative value if an error occurs, 0 if |
| * it needs to wait, any other value otherwise. |
| * - http_payload : Called when some data can be consumed. |
| * Returns a negative value if an error occurs, else |
| * the number of forwarded bytes. |
| * - http_end : Called when all the request/response has been |
| * processed and all body data has been forwarded. |
| * Returns a negative value if an error occurs, 0 if |
| * it needs to wait for some reason, any other value |
| * otherwise. |
| * - http_reset : Called when the HTTP message is reseted. It happens |
| * either when a 100-continue response is received. |
| * that can be detected if s->txn->status is 10X, or |
| * if we're attempting a L7 retry. |
| * Returns nothing. |
| * - http_reply : Called when, at any time, HA proxy decides to stop |
| * the HTTP message's processing and to send a message |
| * to the client (mainly, when an error or a redirect |
| * occur). |
| * Returns nothing. |
| * |
| * |
| * - tcp_payload : Called when some data can be consumed. |
| * Returns a negative value if an error occurs, else |
| * the number of forwarded bytes. |
| */ |
| struct flt_ops { |
| /* |
| * Callbacks to manage the filter lifecycle |
| */ |
| int (*init) (struct proxy *p, struct flt_conf *fconf); |
| void (*deinit) (struct proxy *p, struct flt_conf *fconf); |
| int (*check) (struct proxy *p, struct flt_conf *fconf); |
| int (*init_per_thread) (struct proxy *p, struct flt_conf *fconf); |
| void (*deinit_per_thread)(struct proxy *p, struct flt_conf *fconf); |
| /* |
| * Stream callbacks |
| */ |
| int (*attach) (struct stream *s, struct filter *f); |
| int (*stream_start) (struct stream *s, struct filter *f); |
| int (*stream_set_backend)(struct stream *s, struct filter *f, struct proxy *be); |
| void (*stream_stop) (struct stream *s, struct filter *f); |
| void (*detach) (struct stream *s, struct filter *f); |
| void (*check_timeouts) (struct stream *s, struct filter *f); |
| /* |
| * Channel callbacks |
| */ |
| int (*channel_start_analyze)(struct stream *s, struct filter *f, struct channel *chn); |
| int (*channel_pre_analyze) (struct stream *s, struct filter *f, struct channel *chn, unsigned int an_bit); |
| int (*channel_post_analyze) (struct stream *s, struct filter *f, struct channel *chn, unsigned int an_bit); |
| int (*channel_end_analyze) (struct stream *s, struct filter *f, struct channel *chn); |
| |
| /* |
| * HTTP callbacks |
| */ |
| int (*http_headers) (struct stream *s, struct filter *f, struct http_msg *msg); |
| int (*http_payload) (struct stream *s, struct filter *f, struct http_msg *msg, |
| unsigned int offset, unsigned int len); |
| int (*http_end) (struct stream *s, struct filter *f, struct http_msg *msg); |
| |
| void (*http_reset) (struct stream *s, struct filter *f, struct http_msg *msg); |
| void (*http_reply) (struct stream *s, struct filter *f, short status, |
| const struct buffer *msg); |
| |
| /* |
| * TCP callbacks |
| */ |
| int (*tcp_payload) (struct stream *s, struct filter *f, struct channel *chn, |
| unsigned int offset, unsigned int len); |
| }; |
| |
| /* Flags set on a filter config */ |
| #define FLT_CFG_FL_HTX 0x00000001 /* The filter can filter HTX streams */ |
| |
| /* Flags set on a filter instance */ |
| #define FLT_FL_IS_BACKEND_FILTER 0x0001 /* The filter is a backend filter */ |
| #define FLT_FL_IS_REQ_DATA_FILTER 0x0002 /* The filter will parse data on the request channel */ |
| #define FLT_FL_IS_RSP_DATA_FILTER 0x0004 /* The filter will parse data on the response channel */ |
| |
| /* Flags set on the stream, common to all filters attached to its stream */ |
| #define STRM_FLT_FL_HAS_FILTERS 0x0001 /* The stream has at least one filter */ |
| |
| /* |
| * Structure representing the filter configuration, attached to a proxy and |
| * accessible from a filter when instantiated in a stream |
| */ |
| struct flt_conf { |
| const char *id; /* The filter id */ |
| struct flt_ops *ops; /* The filter callbacks */ |
| void *conf; /* The filter configuration */ |
| struct list list; /* Next filter for the same proxy */ |
| unsigned int flags; /* FLT_CFG_FL_* */ |
| }; |
| |
| /* |
| * Structure reprensenting a filter instance attached to a stream |
| * |
| * 2D-Array fields are used to store info per channel. The first index stands |
| * for the request channel, and the second one for the response channel. |
| * Especially, <next> and <fwd> are offets representing amount of data that the |
| * filter are, respectively, parsed and forwarded on a channel. Filters can |
| * access these values using FLT_NXT and FLT_FWD macros. |
| */ |
| struct filter { |
| struct flt_conf *config; /* the filter's configuration */ |
| void *ctx; /* The filter context (opaque) */ |
| unsigned short flags; /* FLT_FL_* */ |
| unsigned long long offset[2]; /* Offset of input data already filtered for a specific channel |
| * 0: request channel, 1: response channel */ |
| unsigned int pre_analyzers; /* bit field indicating analyzers to pre-process */ |
| unsigned int post_analyzers; /* bit field indicating analyzers to post-process */ |
| struct list list; /* Next filter for the same proxy/stream */ |
| }; |
| |
| /* |
| * Structure reprensenting the "global" state of filters attached to a stream. |
| */ |
| struct strm_flt { |
| struct list filters; /* List of filters attached to a stream */ |
| struct filter *current[2]; /* From which filter resume processing, for a specific channel. |
| * This is used for resumable callbacks only, |
| * If NULL, we start from the first filter. |
| * 0: request channel, 1: response channel */ |
| unsigned short flags; /* STRM_FL_* */ |
| unsigned char nb_req_data_filters; /* Number of data filters registered on the request channel */ |
| unsigned char nb_rsp_data_filters; /* Number of data filters registered on the response channel */ |
| unsigned long long offset[2]; |
| }; |
| |
| #endif /* _TYPES_FILTERS_H */ |
| |
| /* |
| * Local variables: |
| * c-indent-level: 8 |
| * c-basic-offset: 8 |
| * End: |
| */ |