1 /*
2  * include/types/sample.h
3  * Macros, variables and structures for sample management.
4  *
5  * Copyright (C) 2009-2010 EXCELIANCE, Emeric Brun <ebrun@exceliance.fr>
6  * Copyright (C) 2012-2013 Willy Tarreau <w@1wt.eu>
7  *
8  * This library is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation, version 2.1
11  * exclusively.
12  *
13  * This library is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with this library; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
21  */
22 
23 #ifndef _TYPES_SAMPLE_H
24 #define _TYPES_SAMPLE_H
25 
26 #include <sys/socket.h>
27 #include <netinet/in.h>
28 
29 #include <common/chunk.h>
30 #include <common/mini-clist.h>
31 
32 struct arg;
33 
34 /* input and output sample types */
35 enum {
36 	SMP_T_ANY = 0,   /* any type */
37 	SMP_T_BOOL,      /* boolean */
38 	SMP_T_SINT,      /* signed 64bits integer type */
39 	SMP_T_ADDR,      /* ipv4 or ipv6, only used for input type compatibility */
40 	SMP_T_IPV4,      /* ipv4 type */
41 	SMP_T_IPV6,      /* ipv6 type */
42 	SMP_T_STR,       /* char string type */
43 	SMP_T_BIN,       /* buffer type */
44 	SMP_T_METH,      /* contain method */
45 	SMP_TYPES        /* number of types, must always be last */
46 };
47 
48 /* Sample sources are used to establish a relation between fetch keywords and
49  * the location where they're about to be used. They're reserved for internal
50  * use and are not meant to be known outside the sample management code.
51  */
52 enum {
53 	SMP_SRC_INTRN,  /* internal context-less information */
54 	SMP_SRC_LISTN,  /* listener which accepted the connection */
55 	SMP_SRC_FTEND,  /* frontend which accepted the connection */
56 	SMP_SRC_L4CLI,  /* L4 information about the client */
57 	SMP_SRC_L5CLI,  /* fetch uses client information from embryonic session */
58 	SMP_SRC_TRACK,  /* fetch involves track counters */
59 	SMP_SRC_L6REQ,  /* fetch uses raw information from the request buffer */
60 	SMP_SRC_HRQHV,  /* fetch uses volatile information about HTTP request headers (eg: value) */
61 	SMP_SRC_HRQHP,  /* fetch uses persistent information about HTTP request headers (eg: meth) */
62 	SMP_SRC_HRQBO,  /* fetch uses information about HTTP request body */
63 	SMP_SRC_BKEND,  /* fetch uses information about the backend */
64 	SMP_SRC_SERVR,  /* fetch uses information about the selected server */
65 	SMP_SRC_L4SRV,  /* fetch uses information about the server L4 connection */
66 	SMP_SRC_L5SRV,  /* fetch uses information about the server L5 connection */
67 	SMP_SRC_L6RES,  /* fetch uses raw information from the response buffer */
68 	SMP_SRC_HRSHV,  /* fetch uses volatile information about HTTP response headers (eg: value) */
69 	SMP_SRC_HRSHP,  /* fetch uses persistent information about HTTP response headers (eg: status) */
70 	SMP_SRC_HRSBO,  /* fetch uses information about HTTP response body */
71 	SMP_SRC_RQFIN,  /* final information about request buffer (eg: tot bytes) */
72 	SMP_SRC_RSFIN,  /* final information about response buffer (eg: tot bytes) */
73 	SMP_SRC_TXFIN,  /* final information about the transaction (eg: #comp rate) */
74 	SMP_SRC_SSFIN,  /* final information about the stream (eg: #requests, final flags) */
75 	SMP_SRC_ENTRIES /* nothing after this */
76 };
77 
78 /* Sample checkpoints are a list of places where samples may be used. This is
79  * an internal enum used only to build SMP_VAL_*.
80  */
81 enum {
82 	SMP_CKP_FE_CON_ACC,  /* FE connection accept rules ("tcp request connection") */
83 	SMP_CKP_FE_SES_ACC,  /* FE stream accept rules (to come soon) */
84 	SMP_CKP_FE_REQ_CNT,  /* FE request content rules ("tcp request content") */
85 	SMP_CKP_FE_HRQ_HDR,  /* FE HTTP request headers (rules, headers, monitor, stats, redirect) */
86 	SMP_CKP_FE_HRQ_BDY,  /* FE HTTP request body */
87 	SMP_CKP_FE_SET_BCK,  /* FE backend switching rules ("use_backend") */
88 	SMP_CKP_BE_REQ_CNT,  /* BE request content rules ("tcp request content") */
89 	SMP_CKP_BE_HRQ_HDR,  /* BE HTTP request headers (rules, headers, monitor, stats, redirect) */
90 	SMP_CKP_BE_HRQ_BDY,  /* BE HTTP request body */
91 	SMP_CKP_BE_SET_SRV,  /* BE server switching rules ("use_server", "balance", "force-persist", "stick", ...) */
92 	SMP_CKP_BE_SRV_CON,  /* BE server connect (eg: "source") */
93 	SMP_CKP_BE_RES_CNT,  /* BE response content rules ("tcp response content") */
94 	SMP_CKP_BE_HRS_HDR,  /* BE HTTP response headers (rules, headers) */
95 	SMP_CKP_BE_HRS_BDY,  /* BE HTTP response body (stick-store rules are there) */
96 	SMP_CKP_BE_STO_RUL,  /* BE stick-store rules */
97 	SMP_CKP_FE_RES_CNT,  /* FE response content rules ("tcp response content") */
98 	SMP_CKP_FE_HRS_HDR,  /* FE HTTP response headers (rules, headers) */
99 	SMP_CKP_FE_HRS_BDY,  /* FE HTTP response body */
100 	SMP_CKP_FE_LOG_END,  /* FE log at the end of the txn/stream */
101 	SMP_CKP_ENTRIES /* nothing after this */
102 };
103 
104 /* SMP_USE_* are flags used to declare fetch keywords. Fetch methods are
105  * associated with bitfields composed of these values, generally only one, to
106  * indicate where the contents may be sampled. Some fetches are ambiguous as
107  * they apply to either the request or the response depending on the context,
108  * so they will have 2 of these bits (eg: hdr(), payload(), ...). These are
109  * stored in smp->use.
110  */
111 enum {
112 	SMP_USE_INTRN = 1 << SMP_SRC_INTRN,  /* internal context-less information */
113 	SMP_USE_LISTN = 1 << SMP_SRC_LISTN,  /* listener which accepted the connection */
114 	SMP_USE_FTEND = 1 << SMP_SRC_FTEND,  /* frontend which accepted the connection */
115 	SMP_USE_L4CLI = 1 << SMP_SRC_L4CLI,  /* L4 information about the client */
116 	SMP_USE_L5CLI = 1 << SMP_SRC_L5CLI,  /* fetch uses client information from embryonic session */
117 	SMP_USE_TRACK = 1 << SMP_SRC_TRACK,  /* fetch involves track counters */
118 	SMP_USE_L6REQ = 1 << SMP_SRC_L6REQ,  /* fetch uses raw information from the request buffer */
119 	SMP_USE_HRQHV = 1 << SMP_SRC_HRQHV,  /* fetch uses volatile information about HTTP request headers (eg: value) */
120 	SMP_USE_HRQHP = 1 << SMP_SRC_HRQHP,  /* fetch uses persistent information about HTTP request headers (eg: meth) */
121 	SMP_USE_HRQBO = 1 << SMP_SRC_HRQBO,  /* fetch uses information about HTTP request body */
122 	SMP_USE_BKEND = 1 << SMP_SRC_BKEND,  /* fetch uses information about the backend */
123 	SMP_USE_SERVR = 1 << SMP_SRC_SERVR,  /* fetch uses information about the selected server */
124 	SMP_USE_L4SRV = 1 << SMP_SRC_L4SRV,  /* fetch uses information about the server L4 connection */
125 	SMP_USE_L5SRV = 1 << SMP_SRC_L5SRV,  /* fetch uses information about the server L5 connection */
126 	SMP_USE_L6RES = 1 << SMP_SRC_L6RES,  /* fetch uses raw information from the response buffer */
127 	SMP_USE_HRSHV = 1 << SMP_SRC_HRSHV,  /* fetch uses volatile information about HTTP response headers (eg: value) */
128 	SMP_USE_HRSHP = 1 << SMP_SRC_HRSHP,  /* fetch uses persistent information about HTTP response headers (eg: status) */
129 	SMP_USE_HRSBO = 1 << SMP_SRC_HRSBO,  /* fetch uses information about HTTP response body */
130 	SMP_USE_RQFIN = 1 << SMP_SRC_RQFIN,  /* final information about request buffer (eg: tot bytes) */
131 	SMP_USE_RSFIN = 1 << SMP_SRC_RSFIN,  /* final information about response buffer (eg: tot bytes) */
132 	SMP_USE_TXFIN = 1 << SMP_SRC_TXFIN,  /* final information about the transaction (eg: #comp rate) */
133 	SMP_USE_SSFIN = 1 << SMP_SRC_SSFIN,  /* final information about the stream (eg: #requests, final flags) */
134 
135 	/* This composite one is useful to detect if an hdr_idx needs to be allocated */
136 	SMP_USE_HTTP_ANY = SMP_USE_HRQHV | SMP_USE_HRQHP | SMP_USE_HRQBO |
137 	                   SMP_USE_HRSHV | SMP_USE_HRSHP | SMP_USE_HRSBO,
138 };
139 
140 /* Sample validity is computed from the fetch sources above when keywords
141  * are registered. Each fetch method may be used at different locations. The
142  * configuration parser will check whether the fetches are compatible with the
143  * location where they're used. These are stored in smp->val.
144  */
145 enum {
146 	SMP_VAL___________ = 0,        /* Just used as a visual marker */
147 	SMP_VAL_FE_CON_ACC = 1 << SMP_CKP_FE_CON_ACC,  /* FE connection accept rules ("tcp request connection") */
148 	SMP_VAL_FE_SES_ACC = 1 << SMP_CKP_FE_SES_ACC,  /* FE stream accept rules (to come soon) */
149 	SMP_VAL_FE_REQ_CNT = 1 << SMP_CKP_FE_REQ_CNT,  /* FE request content rules ("tcp request content") */
150 	SMP_VAL_FE_HRQ_HDR = 1 << SMP_CKP_FE_HRQ_HDR,  /* FE HTTP request headers (rules, headers, monitor, stats, redirect) */
151 	SMP_VAL_FE_HRQ_BDY = 1 << SMP_CKP_FE_HRQ_BDY,  /* FE HTTP request body */
152 	SMP_VAL_FE_SET_BCK = 1 << SMP_CKP_FE_SET_BCK,  /* FE backend switching rules ("use_backend") */
153 	SMP_VAL_BE_REQ_CNT = 1 << SMP_CKP_BE_REQ_CNT,  /* BE request content rules ("tcp request content") */
154 	SMP_VAL_BE_HRQ_HDR = 1 << SMP_CKP_BE_HRQ_HDR,  /* BE HTTP request headers (rules, headers, monitor, stats, redirect) */
155 	SMP_VAL_BE_HRQ_BDY = 1 << SMP_CKP_BE_HRQ_BDY,  /* BE HTTP request body */
156 	SMP_VAL_BE_SET_SRV = 1 << SMP_CKP_BE_SET_SRV,  /* BE server switching rules ("use_server", "balance", "force-persist", "stick", ...) */
157 	SMP_VAL_BE_SRV_CON = 1 << SMP_CKP_BE_SRV_CON,  /* BE server connect (eg: "source") */
158 	SMP_VAL_BE_RES_CNT = 1 << SMP_CKP_BE_RES_CNT,  /* BE response content rules ("tcp response content") */
159 	SMP_VAL_BE_HRS_HDR = 1 << SMP_CKP_BE_HRS_HDR,  /* BE HTTP response headers (rules, headers) */
160 	SMP_VAL_BE_HRS_BDY = 1 << SMP_CKP_BE_HRS_BDY,  /* BE HTTP response body (stick-store rules are there) */
161 	SMP_VAL_BE_STO_RUL = 1 << SMP_CKP_BE_STO_RUL,  /* BE stick-store rules */
162 	SMP_VAL_FE_RES_CNT = 1 << SMP_CKP_FE_RES_CNT,  /* FE response content rules ("tcp response content") */
163 	SMP_VAL_FE_HRS_HDR = 1 << SMP_CKP_FE_HRS_HDR,  /* FE HTTP response headers (rules, headers) */
164 	SMP_VAL_FE_HRS_BDY = 1 << SMP_CKP_FE_HRS_BDY,  /* FE HTTP response body */
165 	SMP_VAL_FE_LOG_END = 1 << SMP_CKP_FE_LOG_END,  /* FE log at the end of the txn/stream */
166 
167 	/* a few combinations to decide what direction to try to fetch (useful for logs) */
168 	SMP_VAL_REQUEST    = SMP_VAL_FE_CON_ACC | SMP_VAL_FE_SES_ACC | SMP_VAL_FE_REQ_CNT |
169 	                     SMP_VAL_FE_HRQ_HDR | SMP_VAL_FE_HRQ_BDY | SMP_VAL_FE_SET_BCK |
170 	                     SMP_VAL_BE_REQ_CNT | SMP_VAL_BE_HRQ_HDR | SMP_VAL_BE_HRQ_BDY |
171 	                     SMP_VAL_BE_SET_SRV,
172 
173 	SMP_VAL_RESPONSE   = SMP_VAL_BE_SRV_CON | SMP_VAL_BE_RES_CNT | SMP_VAL_BE_HRS_HDR |
174 	                     SMP_VAL_BE_HRS_BDY | SMP_VAL_BE_STO_RUL | SMP_VAL_FE_RES_CNT |
175 	                     SMP_VAL_FE_HRS_HDR | SMP_VAL_FE_HRS_BDY | SMP_VAL_FE_LOG_END,
176 };
177 
178 extern const unsigned int fetch_cap[SMP_SRC_ENTRIES];
179 
180 /* Sample fetch options are passed to sample fetch functions to add precision
181  * about what is desired :
182  *   - fetch direction (req/resp)
183  *   - intermediary / final fetch
184  */
185 enum {
186 	SMP_OPT_DIR_REQ = 0,    /* direction = request */
187 	SMP_OPT_DIR_RES = 1,    /* direction = response */
188 	SMP_OPT_DIR     = (SMP_OPT_DIR_REQ|SMP_OPT_DIR_RES), /* mask to get direction */
189 	SMP_OPT_FINAL   = 2,    /* final fetch, contents won't change anymore */
190 	SMP_OPT_ITERATE = 4,    /* fetches may be iterated if supported (for ACLs) */
191 };
192 
193 /* Flags used to describe fetched samples. MAY_CHANGE indicates that the result
194  * of the fetch might still evolve, for instance because of more data expected,
195  * even if the fetch has failed. VOL_* indicates how long a result may be cached.
196  */
197 enum {
198 	SMP_F_NOT_LAST   = 1 << 0, /* other occurrences might exist for this sample */
199 	SMP_F_MAY_CHANGE = 1 << 1, /* sample is unstable and might change (eg: request length) */
200 	SMP_F_VOL_TEST   = 1 << 2, /* result must not survive longer than the test (eg: time) */
201 	SMP_F_VOL_1ST    = 1 << 3, /* result sensitive to changes in first line (eg: URI) */
202 	SMP_F_VOL_HDR    = 1 << 4, /* result sensitive to changes in headers */
203 	SMP_F_VOL_TXN    = 1 << 5, /* result sensitive to new transaction (eg: HTTP version) */
204 	SMP_F_VOL_SESS   = 1 << 6, /* result sensitive to new session (eg: src IP) */
205 	SMP_F_VOLATILE   = (1<<2)|(1<<3)|(1<<4)|(1<<5)|(1<<6), /* any volatility condition */
206 	SMP_F_CONST      = 1 << 7, /* This sample use constant memory. May diplicate it before changes */
207 };
208 
209 /* needed below */
210 struct session;
211 struct stream;
212 
213 /* Known HTTP methods */
214 enum http_meth_t {
215 	HTTP_METH_OPTIONS,
216 	HTTP_METH_GET,
217 	HTTP_METH_HEAD,
218 	HTTP_METH_POST,
219 	HTTP_METH_PUT,
220 	HTTP_METH_DELETE,
221 	HTTP_METH_TRACE,
222 	HTTP_METH_CONNECT,
223 	HTTP_METH_OTHER, /* Must be the last entry */
224 } __attribute__((packed));
225 
226 /* a sample context might be used by any sample fetch function in order to
227  * store information needed across multiple calls (eg: restart point for a
228  * next occurrence). By definition it may store up to 8 pointers, or any
229  * scalar (double, int, long long).
230  */
231 union smp_ctx {
232 	void *p;        /* any pointer */
233 	int i;          /* any integer */
234 	long long ll;   /* any long long or smaller */
235 	double d;       /* any float or double */
236 	void *a[8];     /* any array of up to 8 pointers */
237 };
238 
239 /* Note: the strings below make use of chunks. Chunks may carry an allocated
240  * size in addition to the length. The size counts from the beginning (str)
241  * to the end. If the size is unknown, it MUST be zero, in which case the
242  * sample will automatically be duplicated when a change larger than <len> has
243  * to be performed. Thus it is safe to always set size to zero.
244  */
245 struct meth {
246 	enum http_meth_t meth;
247 	struct chunk str;
248 };
249 
250 union sample_value {
251 	long long int   sint;  /* used for signed 64bits integers */
252 	struct in_addr  ipv4;  /* used for ipv4 addresses */
253 	struct in6_addr ipv6;  /* used for ipv6 addresses */
254 	struct chunk    str;   /* used for char strings or buffers */
255 	struct meth     meth;  /* used for http method */
256 };
257 
258 /* Used to store sample constant */
259 struct sample_data {
260 	int type;                 /* SMP_T_* */
261 	union sample_value u;     /* sample data */
262 };
263 
264 /* a sample is a typed data extracted from a stream. It has a type, contents,
265  * validity constraints, a context for use in iterative calls.
266  */
267 struct sample {
268 	unsigned int flags;       /* SMP_F_* */
269 	struct sample_data data;
270 	union smp_ctx ctx;
271 
272 	/* Some sample analyzer (sample-fetch or converters) needs to
273 	 * known the attached proxy, session and stream. The sample-fetches
274 	 * and the converters function pointers cannot be called without
275 	 * these 3 pointers filled.
276 	 */
277 	struct proxy *px;
278 	struct session *sess;
279 	struct stream *strm; /* WARNING! MAY BE NULL! (eg: tcp-request connection) */
280 	unsigned int opt; /* fetch options (SMP_OPT_*) */
281 };
282 
283 /* Descriptor for a sample conversion */
284 struct sample_conv {
285 	const char *kw;                           /* configuration keyword  */
286 	int (*process)(const struct arg *arg_p,
287 	               struct sample *smp,
288 	               void *private);            /* process function */
289 	uint64_t arg_mask;                        /* arguments (ARG*()) */
290 	int (*val_args)(struct arg *arg_p,
291 	                struct sample_conv *smp_conv,
292 	                const char *file, int line,
293 			char **err_msg);          /* argument validation function */
294 	unsigned int in_type;                     /* expected input sample type */
295 	unsigned int out_type;                    /* output sample type */
296 	void *private;                            /* private values. only used by maps and Lua */
297 };
298 
299 /* sample conversion expression */
300 struct sample_conv_expr {
301 	struct list list;                         /* member of a sample_expr */
302 	struct sample_conv *conv;                 /* sample conversion used */
303 	struct arg *arg_p;                        /* optional arguments */
304 };
305 
306 /* Descriptor for a sample fetch method */
307 struct sample_fetch {
308 	const char *kw;                           /* configuration keyword */
309 	int (*process)(const struct arg *arg_p,
310 	               struct sample *smp,
311 	               const char *kw,            /* fetch processing function */
312 	               void *private);            /* private value. */
313 	uint64_t arg_mask;                        /* arguments (ARG*()) */
314 	int (*val_args)(struct arg *arg_p,
315 			char **err_msg);          /* argument validation function */
316 	unsigned long out_type;                   /* output sample type */
317 	unsigned int use;                         /* fetch source (SMP_USE_*) */
318 	unsigned int val;                         /* fetch validity (SMP_VAL_*) */
319 	void *private;                            /* private values. only used by Lua */
320 };
321 
322 /* sample expression */
323 struct sample_expr {
324 	struct list list;                         /* member of list of sample, currently not used */
325 	struct sample_fetch *fetch;               /* sample fetch method */
326 	struct arg *arg_p;                        /* optional pointer to arguments to fetch function */
327 	struct list conv_exprs;                   /* list of conversion expression to apply */
328 };
329 
330 /* sample fetch keywords list */
331 struct sample_fetch_kw_list {
332 	struct list list;                         /* head of sample fetch keyword list */
333 	struct sample_fetch kw[VAR_ARRAY];        /* array of sample fetch descriptors */
334 };
335 
336 /* sample conversion keywords list */
337 struct sample_conv_kw_list {
338 	struct list list;                         /* head of sample conversion keyword list */
339 	struct sample_conv kw[VAR_ARRAY];         /* array of sample conversion descriptors */
340 };
341 
342 typedef int (*sample_cast_fct)(struct sample *smp);
343 extern sample_cast_fct sample_casts[SMP_TYPES][SMP_TYPES];
344 
345 #endif /* _TYPES_SAMPLE_H */
346