xref: /netbsd-src/external/ibm-public/postfix/dist/src/util/dict.h (revision 7863ba460b0a05b553c754e5dbc29247dddec322)
1 /*	$NetBSD: dict.h,v 1.2 2017/02/14 01:16:49 christos Exp $	*/
2 
3 #ifndef _DICT_H_INCLUDED_
4 #define _DICT_H_INCLUDED_
5 
6 /*++
7 /* NAME
8 /*	dict 3h
9 /* SUMMARY
10 /*	dictionary manager
11 /* SYNOPSIS
12 /*	#include <dict.h>
13 /* DESCRIPTION
14 /* .nf
15 
16  /*
17   * System library.
18   */
19 #include <fcntl.h>
20 #include <setjmp.h>
21 
22 #ifdef NO_SIGSETJMP
23 #define DICT_JMP_BUF jmp_buf
24 #else
25 #define DICT_JMP_BUF sigjmp_buf
26 #endif
27 
28  /*
29   * Utility library.
30   */
31 #include <vstream.h>
32 #include <argv.h>
33 #include <vstring.h>
34 #include <myflock.h>
35 
36  /*
37   * Provenance information.
38   */
39 typedef struct DICT_OWNER {
40     int     status;			/* see below */
41     uid_t   uid;			/* use only if status == UNTRUSTED */
42 } DICT_OWNER;
43 
44  /*
45   * Note that trust levels are not in numerical order.
46   */
47 #define DICT_OWNER_UNKNOWN	(-1)	/* ex: unauthenticated tcp, proxy */
48 #define DICT_OWNER_TRUSTED	(!1)	/* ex: root-owned config file */
49 #define DICT_OWNER_UNTRUSTED	(!0)	/* ex: non-root config file */
50 
51  /*
52   * When combining tables with different provenance, we initialize to the
53   * highest trust level, and remember the lowest trust level that we find
54   * during aggregation. If we combine tables that are owned by different
55   * untrusted users, the resulting provenance is "unknown".
56   */
57 #define DICT_OWNER_AGGREGATE_INIT(dst) { \
58 	(dst).status = DICT_OWNER_TRUSTED; \
59 	(dst).uid = 0; \
60     } while (0)
61 
62  /*
63   * The following is derived from the 3x3 transition matrix.
64   */
65 #define DICT_OWNER_AGGREGATE_UPDATE(dst, src) do { \
66 	if ((dst).status == DICT_OWNER_TRUSTED \
67 	    || (src).status == DICT_OWNER_UNKNOWN) { \
68 	    (dst) = (src); \
69 	} else if ((dst).status == (src).status \
70 		&& (dst).uid != (src).uid) { \
71 	    (dst).status = DICT_OWNER_UNKNOWN; \
72 	    (dst).uid = ~0; \
73 	} \
74     } while (0)
75 
76  /*
77   * Generic dictionary interface - in reality, a dictionary extends this
78   * structure with private members to maintain internal state.
79   */
80 typedef struct DICT {
81     char   *type;			/* for diagnostics */
82     char   *name;			/* for diagnostics */
83     int     flags;			/* see below */
84     const char *(*lookup) (struct DICT *, const char *);
85     int     (*update) (struct DICT *, const char *, const char *);
86     int     (*delete) (struct DICT *, const char *);
87     int     (*sequence) (struct DICT *, int, const char **, const char **);
88     int     (*lock) (struct DICT *, int);
89     void    (*close) (struct DICT *);
90     int     lock_type;			/* for read/write lock */
91     int     lock_fd;			/* for read/write lock */
92     int     stat_fd;			/* change detection */
93     time_t  mtime;			/* mod time at open */
94     VSTRING *fold_buf;			/* key folding buffer */
95     DICT_OWNER owner;			/* provenance */
96     int     error;			/* last operation only */
97     DICT_JMP_BUF *jbuf;			/* exception handling */
98     struct DICT_UTF8_BACKUP *utf8_backup;	/* see below */
99 } DICT;
100 
101 extern DICT *dict_alloc(const char *, const char *, ssize_t);
102 extern void dict_free(DICT *);
103 
104 extern DICT *dict_debug(DICT *);
105 
106 #define DICT_DEBUG(d) ((d)->flags & DICT_FLAG_DEBUG ? dict_debug(d) : (d))
107 
108  /*
109   * See dict_open.c embedded manpage for flag definitions.
110   */
111 #define DICT_FLAG_NONE		(0)
112 #define DICT_FLAG_DUP_WARN	(1<<0)	/* warn about dups if not supported */
113 #define DICT_FLAG_DUP_IGNORE	(1<<1)	/* ignore dups if not supported */
114 #define DICT_FLAG_TRY0NULL	(1<<2)	/* do not append 0 to key/value */
115 #define DICT_FLAG_TRY1NULL	(1<<3)	/* append 0 to key/value */
116 #define DICT_FLAG_FIXED		(1<<4)	/* fixed key map */
117 #define DICT_FLAG_PATTERN	(1<<5)	/* keys are patterns */
118 #define DICT_FLAG_LOCK		(1<<6)	/* use temp lock before access */
119 #define DICT_FLAG_DUP_REPLACE	(1<<7)	/* replace dups if supported */
120 #define DICT_FLAG_SYNC_UPDATE	(1<<8)	/* sync updates if supported */
121 #define DICT_FLAG_DEBUG		(1<<9)	/* log access */
122 /*#define DICT_FLAG_FOLD_KEY	(1<<10)	/* lowercase the lookup key */
123 #define DICT_FLAG_NO_REGSUB	(1<<11)	/* disallow regexp substitution */
124 #define DICT_FLAG_NO_PROXY	(1<<12)	/* disallow proxy mapping */
125 #define DICT_FLAG_NO_UNAUTH	(1<<13)	/* disallow unauthenticated data */
126 #define DICT_FLAG_FOLD_FIX	(1<<14)	/* case-fold key with fixed-case map */
127 #define DICT_FLAG_FOLD_MUL	(1<<15)	/* case-fold key with multi-case map */
128 #define DICT_FLAG_FOLD_ANY	(DICT_FLAG_FOLD_FIX | DICT_FLAG_FOLD_MUL)
129 #define DICT_FLAG_OPEN_LOCK	(1<<16)	/* perm lock if not multi-writer safe */
130 #define DICT_FLAG_BULK_UPDATE	(1<<17)	/* optimize for bulk updates */
131 #define DICT_FLAG_MULTI_WRITER	(1<<18)	/* multi-writer safe map */
132 #define DICT_FLAG_UTF8_REQUEST	(1<<19)	/* activate UTF-8 if possible */
133 #define DICT_FLAG_UTF8_ACTIVE	(1<<20)	/* UTF-8 proxy layer is present */
134 
135 #define DICT_FLAG_UTF8_MASK	(DICT_FLAG_UTF8_REQUEST)
136 
137  /* IMPORTANT: Update the dict_mask[] table when the above changes */
138 
139  /*
140   * The subsets of flags that control how a map is used. These are relevant
141   * mainly for proxymap support. Note: some categories overlap.
142   *
143   * DICT_FLAG_IMPL_MASK - flags that are set by the map implementation itself.
144   *
145   * DICT_FLAG_PARANOID - requestor flags that forbid the use of insecure map
146   * types for security-sensitive operations. These flags are checked by the
147   * map implementation itself upon open, lookup etc. requests.
148   *
149   * DICT_FLAG_RQST_MASK - all requestor flags, including paranoid flags, that
150   * the requestor may change between open, lookup etc. requests. These
151   * specify requestor properties, not map properties.
152   *
153   * DICT_FLAG_INST_MASK - none of the above flags. The requestor may not change
154   * these flags between open, lookup, etc. requests (although a map may make
155   * changes to its copy of some of these flags). The proxymap server opens
156   * only one map instance for all client requests with the same values of
157   * these flags, and the proxymap client uses its own saved copy of these
158   * flags.
159   */
160 #define DICT_FLAG_PARANOID \
161 	(DICT_FLAG_NO_REGSUB | DICT_FLAG_NO_PROXY | DICT_FLAG_NO_UNAUTH)
162 #define DICT_FLAG_IMPL_MASK	(DICT_FLAG_FIXED | DICT_FLAG_PATTERN | \
163 				DICT_FLAG_MULTI_WRITER)
164 #define DICT_FLAG_RQST_MASK	(DICT_FLAG_FOLD_ANY | DICT_FLAG_LOCK | \
165 				DICT_FLAG_DUP_REPLACE | DICT_FLAG_DUP_WARN | \
166 				DICT_FLAG_DUP_IGNORE | DICT_FLAG_SYNC_UPDATE | \
167 				DICT_FLAG_PARANOID | DICT_FLAG_UTF8_MASK)
168 #define DICT_FLAG_INST_MASK	~(DICT_FLAG_IMPL_MASK | DICT_FLAG_RQST_MASK)
169 
170  /*
171   * Feature tests.
172   */
173 #define DICT_NEED_UTF8_ACTIVATION(enable, flags) \
174 	((enable) && ((flags) & DICT_FLAG_UTF8_MASK))
175 
176  /*
177   * dict->error values. Errors must be negative; smtpd_check depends on this.
178   */
179 #define DICT_ERR_NONE	0		/* no error */
180 #define DICT_ERR_RETRY	(-1)		/* soft error */
181 #define DICT_ERR_CONFIG	(-2)		/* configuration error */
182 
183  /*
184   * Result values for exposed functions except lookup. FAIL/ERROR are
185   * suggested values, not for use in comparisons for equality.
186   */
187 #define DICT_STAT_FAIL		1	/* any value > 0: notfound, conflict */
188 #define DICT_STAT_SUCCESS	0	/* request satisfied */
189 #define DICT_STAT_ERROR		(-1)	/* any value < 0: database error */
190 
191  /*
192   * Set an error code and return a result value.
193   */
194 #define DICT_ERR_VAL_RETURN(dict, err, val) do { \
195 	(dict)->error = (err); \
196 	return (val); \
197     } while (0)
198 
199  /*
200   * Sequence function types.
201   */
202 #define DICT_SEQ_FUN_FIRST     0	/* set cursor to first record */
203 #define DICT_SEQ_FUN_NEXT      1	/* set cursor to next record */
204 
205  /*
206   * Interface for dictionary types.
207   */
208 extern ARGV *dict_mapnames(void);
209 typedef void (*DICT_MAPNAMES_EXTEND_FN) (ARGV *);
210 extern DICT_MAPNAMES_EXTEND_FN dict_mapnames_extend(DICT_MAPNAMES_EXTEND_FN);
211 
212 
213  /*
214   * High-level interface, with logical dictionary names.
215   */
216 extern void dict_register(const char *, DICT *);
217 extern DICT *dict_handle(const char *);
218 extern void dict_unregister(const char *);
219 extern int dict_update(const char *, const char *, const char *);
220 extern const char *dict_lookup(const char *, const char *);
221 extern int dict_delete(const char *, const char *);
222 extern int dict_sequence(const char *, const int, const char **, const char **);
223 extern int dict_load_file_xt(const char *, const char *);
224 extern void dict_load_fp(const char *, VSTREAM *);
225 extern const char *dict_eval(const char *, const char *, int);
226 extern int dict_error(const char *);
227 
228  /*
229   * Low-level interface, with physical dictionary handles.
230   */
231 typedef DICT *(*DICT_OPEN_FN) (const char *, int, int);
232 typedef DICT_OPEN_FN (*DICT_OPEN_EXTEND_FN) (const char *);
233 extern DICT *dict_open(const char *, int, int);
234 extern DICT *dict_open3(const char *, const char *, int, int);
235 extern void dict_open_register(const char *, DICT_OPEN_FN);
236 extern DICT_OPEN_EXTEND_FN dict_open_extend(DICT_OPEN_EXTEND_FN);
237 
238 #define dict_get(dp, key)	((const char *) (dp)->lookup((dp), (key)))
239 #define dict_put(dp, key, val)	(dp)->update((dp), (key), (val))
240 #define dict_del(dp, key)	(dp)->delete((dp), (key))
241 #define dict_seq(dp, f, key, val) (dp)->sequence((dp), (f), (key), (val))
242 #define dict_close(dp)		(dp)->close(dp)
243 typedef void (*DICT_WALK_ACTION) (const char *, DICT *, void *);
244 extern void dict_walk(DICT_WALK_ACTION, void *);
245 extern int dict_changed(void);
246 extern const char *dict_changed_name(void);
247 extern const char *dict_flags_str(int);
248 extern int dict_flags_mask(const char *);
249 extern void dict_type_override(DICT *, const char *);
250 
251  /*
252   * Check and convert UTF-8 keys and values.
253   */
254 typedef struct DICT_UTF8_BACKUP {
255     const char *(*lookup) (struct DICT *, const char *);
256     int     (*update) (struct DICT *, const char *, const char *);
257     int     (*delete) (struct DICT *, const char *);
258 } DICT_UTF8_BACKUP;
259 
260 extern DICT *dict_utf8_activate(DICT *);
261 
262  /*
263   * Driver for interactive or scripted tests.
264   */
265 void    dict_test(int, char **);
266 
267  /*
268   * Behind-the-scenes support to continue execution with reduced
269   * functionality.
270   */
271 extern int dict_allow_surrogate;
272 extern DICT *PRINTFLIKE(5, 6) dict_surrogate(const char *, const char *, int, int, const char *,...);
273 
274  /*
275   * This name is reserved for matchlist error handling.
276   */
277 #define DICT_TYPE_NOFILE	"non-existent"
278 #define DICT_TYPE_NOUTF8	"non-UTF-8"
279 
280  /*
281   * Duplicated from vstream(3). This should probably be abstracted out.
282   *
283   * Exception handling. We use pointer to jmp_buf to avoid a lot of unused
284   * baggage for streams that don't need this functionality.
285   *
286   * XXX sigsetjmp()/siglongjmp() save and restore the signal mask which can
287   * avoid surprises in code that manipulates signals, but unfortunately some
288   * systems have bugs in their implementation.
289   */
290 #ifdef NO_SIGSETJMP
291 #define dict_setjmp(dict)	setjmp((dict)->jbuf[0])
292 #define dict_longjmp(dict, val)	longjmp((dict)->jbuf[0], (val))
293 #else
294 #define dict_setjmp(dict)	sigsetjmp((dict)->jbuf[0], 1)
295 #define dict_longjmp(dict, val)	siglongjmp((dict)->jbuf[0], (val))
296 #endif
297 #define dict_isjmp(dict)	((dict)->jbuf != 0)
298 
299  /*
300   * Temporary API. If exception handling proves to be useful,
301   * dict_jmp_alloc() should be integrated into dict_alloc().
302   */
303 extern void dict_jmp_alloc(DICT *);
304 
305 /* LICENSE
306 /* .ad
307 /* .fi
308 /*	The Secure Mailer license must be distributed with this software.
309 /* AUTHOR(S)
310 /*	Wietse Venema
311 /*	IBM T.J. Watson Research
312 /*	P.O. Box 704
313 /*	Yorktown Heights, NY 10598, USA
314 /*--*/
315 
316 #endif
317