1 /*
2 * include/proto/filters.h
3 * This file defines function prototypes for stream filters management.
4 *
5 * Copyright (C) 2015 Qualys Inc., Christopher Faulet <cfaulet@qualys.com>
6 *
7 * This library is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation, version 2.1
10 * exclusively.
11 *
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with this library; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21 #ifndef _PROTO_FILTERS_H
22 #define _PROTO_FILTERS_H
23
24 #include <types/channel.h>
25 #include <types/filters.h>
26 #include <types/http_ana.h>
27 #include <types/proxy.h>
28 #include <types/stream.h>
29
30 #include <proto/channel.h>
31
32 extern const char *trace_flt_id;
33 extern const char *http_comp_flt_id;
34 extern const char *cache_store_flt_id;
35 extern const char *spoe_filter_id;
36 extern const char *fcgi_flt_id;
37
38 #define FLT_ID(flt) (flt)->config->id
39 #define FLT_CONF(flt) (flt)->config->conf
40 #define FLT_OPS(flt) (flt)->config->ops
41
42 /* Useful macros to access per-channel values. It can be safely used inside
43 * filters. */
44 #define CHN_IDX(chn) (((chn)->flags & CF_ISRESP) == CF_ISRESP)
45 #define FLT_STRM_OFF(s, chn) (strm_flt(s)->offset[CHN_IDX(chn)])
46 #define FLT_OFF(flt, chn) ((flt)->offset[CHN_IDX(chn)])
47
48 #define HAS_FILTERS(strm) ((strm)->strm_flt.flags & STRM_FLT_FL_HAS_FILTERS)
49
50 #define HAS_REQ_DATA_FILTERS(strm) ((strm)->strm_flt.nb_req_data_filters != 0)
51 #define HAS_RSP_DATA_FILTERS(strm) ((strm)->strm_flt.nb_rsp_data_filters != 0)
52 #define HAS_DATA_FILTERS(strm, chn) (((chn)->flags & CF_ISRESP) ? HAS_RSP_DATA_FILTERS(strm) : HAS_REQ_DATA_FILTERS(strm))
53
54 #define IS_REQ_DATA_FILTER(flt) ((flt)->flags & FLT_FL_IS_REQ_DATA_FILTER)
55 #define IS_RSP_DATA_FILTER(flt) ((flt)->flags & FLT_FL_IS_RSP_DATA_FILTER)
56 #define IS_DATA_FILTER(flt, chn) (((chn)->flags & CF_ISRESP) ? IS_RSP_DATA_FILTER(flt) : IS_REQ_DATA_FILTER(flt))
57
58 #define FLT_STRM_CB(strm, call) \
59 do { \
60 if (HAS_FILTERS(strm)) { call; } \
61 } while (0)
62
63 #define FLT_STRM_DATA_CB_IMPL_1(strm, chn, call, default_ret) \
64 (HAS_DATA_FILTERS(strm, chn) ? call : default_ret)
65 #define FLT_STRM_DATA_CB_IMPL_2(strm, chn, call, default_ret, on_error) \
66 ({ \
67 int _ret; \
68 if (HAS_DATA_FILTERS(strm, chn)) { \
69 _ret = call; \
70 if (_ret < 0) { on_error; } \
71 } \
72 else \
73 _ret = default_ret; \
74 _ret; \
75 })
76 #define FLT_STRM_DATA_CB_IMPL_3(strm, chn, call, default_ret, on_error, on_wait) \
77 ({ \
78 int _ret; \
79 if (HAS_DATA_FILTERS(strm, chn)) { \
80 _ret = call; \
81 if (_ret < 0) { on_error; } \
82 if (!_ret) { on_wait; } \
83 } \
84 else \
85 _ret = default_ret; \
86 _ret; \
87 })
88
89 #define FLT_STRM_DATA_CB_IMPL_X(strm, chn, call, A, B, C, DATA_CB_IMPL, ...) \
90 DATA_CB_IMPL
91
92 #define FLT_STRM_DATA_CB(strm, chn, call, ...) \
93 FLT_STRM_DATA_CB_IMPL_X(strm, chn, call, ##__VA_ARGS__, \
94 FLT_STRM_DATA_CB_IMPL_3(strm, chn, call, ##__VA_ARGS__), \
95 FLT_STRM_DATA_CB_IMPL_2(strm, chn, call, ##__VA_ARGS__), \
96 FLT_STRM_DATA_CB_IMPL_1(strm, chn, call, ##__VA_ARGS__))
97
98 void flt_deinit(struct proxy *p);
99 int flt_check(struct proxy *p);
100
101 int flt_stream_start(struct stream *s);
102 void flt_stream_stop(struct stream *s);
103 int flt_set_stream_backend(struct stream *s, struct proxy *be);
104 int flt_stream_init(struct stream *s);
105 void flt_stream_release(struct stream *s, int only_backend);
106 void flt_stream_check_timeouts(struct stream *s);
107
108 int flt_http_payload(struct stream *s, struct http_msg *msg, unsigned int len);
109 int flt_http_end(struct stream *s, struct http_msg *msg);
110
111 void flt_http_reset(struct stream *s, struct http_msg *msg);
112 void flt_http_reply(struct stream *s, short status, const struct buffer *msg);
113
114 int flt_start_analyze(struct stream *s, struct channel *chn, unsigned int an_bit);
115 int flt_pre_analyze(struct stream *s, struct channel *chn, unsigned int an_bit);
116 int flt_post_analyze(struct stream *s, struct channel *chn, unsigned int an_bit);
117 int flt_analyze_http_headers(struct stream *s, struct channel *chn, unsigned int an_bit);
118 int flt_end_analyze(struct stream *s, struct channel *chn, unsigned int an_bit);
119
120 int flt_xfer_data(struct stream *s, struct channel *chn, unsigned int an_bit);
121
122 void flt_register_keywords(struct flt_kw_list *kwl);
123 struct flt_kw *flt_find_kw(const char *kw);
124 void flt_dump_kws(char **out);
125 void list_filters(FILE *out);
126
127 /* Helper function that returns the "global" state of filters attached to a
128 * stream. */
129 static inline struct strm_flt *
strm_flt(struct stream * s)130 strm_flt(struct stream *s)
131 {
132 return &s->strm_flt;
133 }
134
135 /* Registers a filter to a channel. If a filter was already registered, this
136 * function do nothing. Once registered, the filter becomes a "data" filter for
137 * this channel. */
138 static inline void
register_data_filter(struct stream * s,struct channel * chn,struct filter * filter)139 register_data_filter(struct stream *s, struct channel *chn, struct filter *filter)
140 {
141 if (!IS_DATA_FILTER(filter, chn)) {
142 if (chn->flags & CF_ISRESP) {
143 filter->flags |= FLT_FL_IS_RSP_DATA_FILTER;
144 strm_flt(s)->nb_rsp_data_filters++;
145 }
146 else {
147 filter->flags |= FLT_FL_IS_REQ_DATA_FILTER;
148 strm_flt(s)->nb_req_data_filters++;
149 }
150 }
151 }
152
153 /* Unregisters a "data" filter from a channel. */
154 static inline void
unregister_data_filter(struct stream * s,struct channel * chn,struct filter * filter)155 unregister_data_filter(struct stream *s, struct channel *chn, struct filter *filter)
156 {
157 if (IS_DATA_FILTER(filter, chn)) {
158 if (chn->flags & CF_ISRESP) {
159 filter->flags &= ~FLT_FL_IS_RSP_DATA_FILTER;
160 strm_flt(s)->nb_rsp_data_filters--;
161
162 }
163 else {
164 filter->flags &= ~FLT_FL_IS_REQ_DATA_FILTER;
165 strm_flt(s)->nb_req_data_filters--;
166 }
167 }
168 }
169
170 /* This function must be called when a filter alter payload data. It updates
171 * offsets of all previous filters. Do not call this function when a filter
172 * change the size of payload data leads to an undefined behavior.
173 *
174 * This is the filter's responsiblitiy to update data itself.
175 */
176 static inline void
flt_update_offsets(struct filter * filter,struct channel * chn,int len)177 flt_update_offsets(struct filter *filter, struct channel *chn, int len)
178 {
179 struct stream *s = chn_strm(chn);
180 struct filter *f;
181
182 list_for_each_entry(f, &strm_flt(s)->filters, list) {
183 if (f == filter)
184 break;
185 FLT_OFF(f, chn) += len;
186 }
187 }
188
189
190 #endif /* _PROTO_FILTERS_H */
191