1 /*
2 * include/haproxy/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 _HAPROXY_FILTERS_H
22 #define _HAPROXY_FILTERS_H
23
24 #include <haproxy/channel.h>
25 #include <haproxy/filters-t.h>
26 #include <haproxy/http_ana-t.h>
27 #include <haproxy/proxy-t.h>
28 #include <haproxy/stream-t.h>
29
30 extern const char *trace_flt_id;
31 extern const char *http_comp_flt_id;
32 extern const char *cache_store_flt_id;
33 extern const char *spoe_filter_id;
34 extern const char *fcgi_flt_id;
35
36 #define FLT_ID(flt) (flt)->config->id
37 #define FLT_CONF(flt) (flt)->config->conf
38 #define FLT_OPS(flt) (flt)->config->ops
39
40 /* Useful macros to access per-channel values. It can be safely used inside
41 * filters. */
42 #define CHN_IDX(chn) (((chn)->flags & CF_ISRESP) == CF_ISRESP)
43 #define FLT_STRM_OFF(s, chn) (strm_flt(s)->offset[CHN_IDX(chn)])
44 #define FLT_OFF(flt, chn) ((flt)->offset[CHN_IDX(chn)])
45
46 #define HAS_FILTERS(strm) ((strm)->strm_flt.flags & STRM_FLT_FL_HAS_FILTERS)
47
48 #define HAS_REQ_DATA_FILTERS(strm) ((strm)->strm_flt.nb_req_data_filters != 0)
49 #define HAS_RSP_DATA_FILTERS(strm) ((strm)->strm_flt.nb_rsp_data_filters != 0)
50 #define HAS_DATA_FILTERS(strm, chn) (((chn)->flags & CF_ISRESP) ? HAS_RSP_DATA_FILTERS(strm) : HAS_REQ_DATA_FILTERS(strm))
51
52 #define IS_REQ_DATA_FILTER(flt) ((flt)->flags & FLT_FL_IS_REQ_DATA_FILTER)
53 #define IS_RSP_DATA_FILTER(flt) ((flt)->flags & FLT_FL_IS_RSP_DATA_FILTER)
54 #define IS_DATA_FILTER(flt, chn) (((chn)->flags & CF_ISRESP) ? IS_RSP_DATA_FILTER(flt) : IS_REQ_DATA_FILTER(flt))
55
56 #define FLT_STRM_CB(strm, call) \
57 do { \
58 if (HAS_FILTERS(strm)) { call; } \
59 } while (0)
60
61 #define FLT_STRM_DATA_CB_IMPL_1(strm, chn, call, default_ret) \
62 (HAS_DATA_FILTERS(strm, chn) ? call : default_ret)
63 #define FLT_STRM_DATA_CB_IMPL_2(strm, chn, call, default_ret, on_error) \
64 ({ \
65 int _ret; \
66 if (HAS_DATA_FILTERS(strm, chn)) { \
67 _ret = call; \
68 if (_ret < 0) { on_error; } \
69 } \
70 else \
71 _ret = default_ret; \
72 _ret; \
73 })
74 #define FLT_STRM_DATA_CB_IMPL_3(strm, chn, call, default_ret, on_error, on_wait) \
75 ({ \
76 int _ret; \
77 if (HAS_DATA_FILTERS(strm, chn)) { \
78 _ret = call; \
79 if (_ret < 0) { on_error; } \
80 if (!_ret) { on_wait; } \
81 } \
82 else \
83 _ret = default_ret; \
84 _ret; \
85 })
86
87 #define FLT_STRM_DATA_CB_IMPL_X(strm, chn, call, A, B, C, DATA_CB_IMPL, ...) \
88 DATA_CB_IMPL
89
90 #define FLT_STRM_DATA_CB(strm, chn, call, ...) \
91 FLT_STRM_DATA_CB_IMPL_X(strm, chn, call, ##__VA_ARGS__, \
92 FLT_STRM_DATA_CB_IMPL_3(strm, chn, call, ##__VA_ARGS__), \
93 FLT_STRM_DATA_CB_IMPL_2(strm, chn, call, ##__VA_ARGS__), \
94 FLT_STRM_DATA_CB_IMPL_1(strm, chn, call, ##__VA_ARGS__))
95
96 void flt_deinit(struct proxy *p);
97 int flt_check(struct proxy *p);
98
99 int flt_stream_start(struct stream *s);
100 void flt_stream_stop(struct stream *s);
101 int flt_set_stream_backend(struct stream *s, struct proxy *be);
102 int flt_stream_init(struct stream *s);
103 void flt_stream_release(struct stream *s, int only_backend);
104 void flt_stream_check_timeouts(struct stream *s);
105
106 int flt_http_payload(struct stream *s, struct http_msg *msg, unsigned int len);
107 int flt_http_end(struct stream *s, struct http_msg *msg);
108
109 void flt_http_reset(struct stream *s, struct http_msg *msg);
110 void flt_http_reply(struct stream *s, short status, const struct buffer *msg);
111
112 int flt_start_analyze(struct stream *s, struct channel *chn, unsigned int an_bit);
113 int flt_pre_analyze(struct stream *s, struct channel *chn, unsigned int an_bit);
114 int flt_post_analyze(struct stream *s, struct channel *chn, unsigned int an_bit);
115 int flt_analyze_http_headers(struct stream *s, struct channel *chn, unsigned int an_bit);
116 int flt_end_analyze(struct stream *s, struct channel *chn, unsigned int an_bit);
117
118 int flt_xfer_data(struct stream *s, struct channel *chn, unsigned int an_bit);
119
120 void flt_register_keywords(struct flt_kw_list *kwl);
121 struct flt_kw *flt_find_kw(const char *kw);
122 void flt_dump_kws(char **out);
123 void list_filters(FILE *out);
124
125 /* Helper function that returns the "global" state of filters attached to a
126 * stream. */
127 static inline struct strm_flt *
strm_flt(struct stream * s)128 strm_flt(struct stream *s)
129 {
130 return &s->strm_flt;
131 }
132
133 /* Registers a filter to a channel. If a filter was already registered, this
134 * function do nothing. Once registered, the filter becomes a "data" filter for
135 * this channel. */
136 static inline void
register_data_filter(struct stream * s,struct channel * chn,struct filter * filter)137 register_data_filter(struct stream *s, struct channel *chn, struct filter *filter)
138 {
139 if (!IS_DATA_FILTER(filter, chn)) {
140 if (chn->flags & CF_ISRESP) {
141 filter->flags |= FLT_FL_IS_RSP_DATA_FILTER;
142 strm_flt(s)->nb_rsp_data_filters++;
143 }
144 else {
145 filter->flags |= FLT_FL_IS_REQ_DATA_FILTER;
146 strm_flt(s)->nb_req_data_filters++;
147 }
148 }
149 }
150
151 /* Unregisters a "data" filter from a channel. */
152 static inline void
unregister_data_filter(struct stream * s,struct channel * chn,struct filter * filter)153 unregister_data_filter(struct stream *s, struct channel *chn, struct filter *filter)
154 {
155 if (IS_DATA_FILTER(filter, chn)) {
156 if (chn->flags & CF_ISRESP) {
157 filter->flags &= ~FLT_FL_IS_RSP_DATA_FILTER;
158 strm_flt(s)->nb_rsp_data_filters--;
159
160 }
161 else {
162 filter->flags &= ~FLT_FL_IS_REQ_DATA_FILTER;
163 strm_flt(s)->nb_req_data_filters--;
164 }
165 }
166 }
167
168 /* This function must be called when a filter alter payload data. It updates
169 * offsets of all previous filters. Do not call this function when a filter
170 * change the size of payload data leads to an undefined behavior.
171 *
172 * This is the filter's responsiblitiy to update data itself.
173 */
174 static inline void
flt_update_offsets(struct filter * filter,struct channel * chn,int len)175 flt_update_offsets(struct filter *filter, struct channel *chn, int len)
176 {
177 struct stream *s = chn_strm(chn);
178 struct filter *f;
179
180 list_for_each_entry(f, &strm_flt(s)->filters, list) {
181 if (f == filter)
182 break;
183 FLT_OFF(f, chn) += len;
184 }
185 }
186
187 #endif /* _HAPROXY_FILTERS_H */
188