| /* |
| * 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 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. The function also has an |
| * access to the current "server" config line. The ->skip value tells the parser |
| * how many words have to be skipped after the keyword. If the function needs to |
| * parse more keywords, it needs to update cur_arg. |
| */ |
| struct flt_kw { |
| const char *kw; |
| int (*parse)(char **args, int *cur_arg, struct proxy *px, |
| struct filter *filter, char **err); |
| }; |
| |
| /* |
| * 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]; |
| }; |
| |
| /* |
| * Filter flags set for a specific filter on channel |
| * |
| * - FILTER_FL_FORWARD_DATA : When this flag is set, the rest of the data is |
| * directly forwarded. For chunk-encoded HTTP |
| * messages, this flag is reseted between each |
| * chunks. |
| */ |
| #define FILTER_FL_FORWARD_DATA 0x00000001 |
| |
| |
| /* |
| * 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. |
| * |
| * |
| * - stream_start : Called when a stream is started. This callback will |
| * only be called for filters defined on a proxy with |
| * the frontend capability. |
| * 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 a proxy with |
| * the frontend capability. |
| * |
| * |
| * - 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_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_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 just before headers sending and parsing of |
| * the body. At this step, headers are fully parsed |
| * and the processing on it is finished. |
| * Returns a negative value if an error occurs, 0 if |
| * it needs to read more data (or to wait for some |
| * reason), any other value otherwise. |
| * - http_start_chunk : Called when we start to process a new chunk |
| * (for chunk-encoded request/response only). At this |
| * step, the chunk length is known and non-null. |
| * Returns a negative value if an error occurs, 0 if |
| * it needs to read more data (or to wait for some |
| * reason), any other value otherwise. |
| * - http_data : Called when unparsed body data are available. |
| * Returns a negative value if an error occurs, else |
| * the number of consumed bytes. |
| * - http_last_chunk : Called when the last chunk (with a zero length) is |
| * received. |
| * Returns a negative value if an error occurs, 0 if |
| * it needs to read more data (or to wait for some |
| * reason), any other value otherwise. |
| * - http_end_chunk : Called at the end of a chunk (expect for the last |
| * one). |
| * Returns a negative value if an error occurs, 0 if |
| * it needs to read more data (or to wait for some |
| * reason), any other value otherwise. |
| * - http_chunk_trailers : Called when part of trailer headers of a |
| * chunk-encoded request/response are ready to be |
| * processed. |
| * Returns a negative value if an error occurs, any |
| * other value otherwise. |
| * - 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 |
| * when a 100-continue response is received. |
| * 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. |
| * - http_forward_data : Called when some data can be consumed. |
| * Returns a negative value if an error occurs, else |
| * the number of forwarded bytes. |
| * - tcp_data : Called when unparsed data are available. |
| * Returns a negative value if an error occurs, else |
| * the number of consumed bytes. |
| * - tcp_forward_data : Called when some data can be consumed. |
| * Returns a negative value if an error occurs, else |
| * or the number of forwarded bytes. |
| */ |
| struct flt_ops { |
| /* |
| * Callbacks to manage the filter lifecycle |
| */ |
| int (*init) (struct proxy *p, struct filter *f); |
| void (*deinit)(struct proxy *p, struct filter *f); |
| int (*check) (struct proxy *p, struct filter *f); |
| |
| /* |
| * Stream callbacks |
| */ |
| int (*stream_start) (struct stream *s, struct filter *f); |
| void (*stream_stop) (struct stream *s, struct filter *f); |
| |
| /* |
| * Channel callbacks |
| */ |
| int (*channel_start_analyze)(struct stream *s, struct filter *f, struct channel *chn); |
| int (*channel_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_start_chunk) (struct stream *s, struct filter *f, struct http_msg *msg); |
| int (*http_data) (struct stream *s, struct filter *f, struct http_msg *msg); |
| int (*http_last_chunk) (struct stream *s, struct filter *f, struct http_msg *msg); |
| int (*http_end_chunk) (struct stream *s, struct filter *f, struct http_msg *msg); |
| int (*http_chunk_trailers)(struct stream *s, struct filter *f, struct http_msg *msg); |
| 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 chunk *msg); |
| int (*http_forward_data) (struct stream *s, struct filter *f, struct http_msg *msg, |
| unsigned int len); |
| |
| /* |
| * TCP callbacks |
| */ |
| int (*tcp_data) (struct stream *s, struct filter *f, struct channel *chn); |
| int (*tcp_forward_data)(struct stream *s, struct filter *f, struct channel *chn, |
| unsigned int len); |
| }; |
| |
| /* |
| * Structure representing the state of a filter. When attached to a proxy, only |
| * <ops> and <conf> field (and optionnaly <id>) are set. All other fields are |
| * used when the filter is 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 { |
| const char *id; /* The filter id */ |
| struct flt_ops *ops; /* The filter callbacks */ |
| void *conf; /* The filter configuration */ |
| void *ctx; /* The filter context (opaque) */ |
| int is_backend_filter; /* Flag to specify if the filter is a "backend" filter */ |
| unsigned int flags[2]; /* 0: request, 1: response */ |
| unsigned int next[2]; /* Offset, relative to buf->p, to the next byte to parse for a specific channel |
| * 0: request channel, 1: response channel */ |
| unsigned int fwd[2]; /* Offset, relative to buf->p, to the next byte to forward for a specific channel |
| * 0: request channel, 1: response channel */ |
| struct list list; /* Next filter for the same proxy/stream */ |
| }; |
| |
| #endif /* _TYPES_FILTERS_H */ |
| |
| /* |
| * Local variables: |
| * c-indent-level: 8 |
| * c-basic-offset: 8 |
| * End: |
| */ |