xref: /src/crypto/openssl/include/openssl/trace.h (revision f25b8c9fb4f58cf61adb47d7570abe7caa6d385d)
1 /*
2  * Copyright 2019-2023 The OpenSSL Project Authors. All Rights Reserved.
3  *
4  * Licensed under the Apache License 2.0 (the "License").  You may not use
5  * this file except in compliance with the License.  You can obtain a copy
6  * in the file LICENSE in the source distribution or at
7  * https://www.openssl.org/source/license.html
8  */
9 
10 #ifndef OPENSSL_TRACE_H
11 #define OPENSSL_TRACE_H
12 #pragma once
13 
14 #include <stdarg.h>
15 
16 #include <openssl/bio.h>
17 
18 #ifdef __cplusplus
19 extern "C" {
20 #endif
21 
22 /*
23  * TRACE CATEGORIES
24  */
25 
26 /*
27  * The trace messages of the OpenSSL libraries are organized into different
28  * categories. For every trace category, the application can register a separate
29  * tracer callback. When a callback is registered, a so called trace channel is
30  * created for this category. This channel consists essentially of an internal
31  * BIO which sends all trace output it receives to the registered application
32  * callback.
33  *
34  * The ALL category can be used as a fallback category to register a single
35  * channel which receives the output from all categories. However, if the
36  * application intends to print the trace channel name in the line prefix,
37  * it is better to register channels for all categories separately.
38  * (This is how the openssl application does it.)
39  */
40 #define OSSL_TRACE_CATEGORY_ALL 0 /* The fallback */
41 #define OSSL_TRACE_CATEGORY_TRACE 1
42 #define OSSL_TRACE_CATEGORY_INIT 2
43 #define OSSL_TRACE_CATEGORY_TLS 3
44 #define OSSL_TRACE_CATEGORY_TLS_CIPHER 4
45 #define OSSL_TRACE_CATEGORY_CONF 5
46 #define OSSL_TRACE_CATEGORY_ENGINE_TABLE 6
47 #define OSSL_TRACE_CATEGORY_ENGINE_REF_COUNT 7
48 #define OSSL_TRACE_CATEGORY_PKCS5V2 8
49 #define OSSL_TRACE_CATEGORY_PKCS12_KEYGEN 9
50 #define OSSL_TRACE_CATEGORY_PKCS12_DECRYPT 10
51 #define OSSL_TRACE_CATEGORY_X509V3_POLICY 11
52 #define OSSL_TRACE_CATEGORY_BN_CTX 12
53 #define OSSL_TRACE_CATEGORY_CMP 13
54 #define OSSL_TRACE_CATEGORY_STORE 14
55 #define OSSL_TRACE_CATEGORY_DECODER 15
56 #define OSSL_TRACE_CATEGORY_ENCODER 16
57 #define OSSL_TRACE_CATEGORY_REF_COUNT 17
58 #define OSSL_TRACE_CATEGORY_HTTP 18
59 #define OSSL_TRACE_CATEGORY_PROVIDER 19
60 #define OSSL_TRACE_CATEGORY_QUERY 20
61 #define OSSL_TRACE_CATEGORY_NUM 21
62 /* KEEP THIS LIST IN SYNC with trace_categories[] in crypto/trace.c */
63 
64 /* Returns the trace category number for the given |name| */
65 int OSSL_trace_get_category_num(const char *name);
66 
67 /* Returns the trace category name for the given |num| */
68 const char *OSSL_trace_get_category_name(int num);
69 
70 /*
71  * TRACE CONSUMERS
72  */
73 
74 /*
75  * Enables tracing for the given |category| by providing a BIO sink
76  * as |channel|. If a null pointer is passed as |channel|, an existing
77  * trace channel is removed and tracing for the category is disabled.
78  *
79  * Returns 1 on success and 0 on failure
80  */
81 int OSSL_trace_set_channel(int category, BIO *channel);
82 
83 /*
84  * Attach a prefix and a suffix to the given |category|, to be printed at the
85  * beginning and at the end of each trace output group, i.e. when
86  * OSSL_trace_begin() and OSSL_trace_end() are called.
87  * If a null pointer is passed as argument, the existing prefix or suffix is
88  * removed.
89  *
90  * They return 1 on success and 0 on failure
91  */
92 int OSSL_trace_set_prefix(int category, const char *prefix);
93 int OSSL_trace_set_suffix(int category, const char *suffix);
94 
95 /*
96  * OSSL_trace_cb is the type tracing callback provided by the application.
97  * It MUST return the number of bytes written, or 0 on error (in other words,
98  * it can never write zero bytes).
99  *
100  * The |buffer| will always contain text, which may consist of several lines.
101  * The |data| argument points to whatever data was provided by the application
102  * when registering the tracer function.
103  *
104  * The |category| number is given, as well as a |cmd| number, described below.
105  */
106 typedef size_t (*OSSL_trace_cb)(const char *buffer, size_t count,
107     int category, int cmd, void *data);
108 /*
109  * Possible |cmd| numbers.
110  */
111 #define OSSL_TRACE_CTRL_BEGIN 0
112 #define OSSL_TRACE_CTRL_WRITE 1
113 #define OSSL_TRACE_CTRL_END 2
114 
115 /*
116  * Enables tracing for the given |category| by creating an internal
117  * trace channel which sends the output to the given |callback|.
118  * If a null pointer is passed as callback, an existing trace channel
119  * is removed and tracing for the category is disabled.
120  *
121  * NOTE: OSSL_trace_set_channel() and OSSL_trace_set_callback() are mutually
122  *       exclusive.
123  *
124  * Returns 1 on success and 0 on failure
125  */
126 int OSSL_trace_set_callback(int category, OSSL_trace_cb callback, void *data);
127 
128 /*
129  * TRACE PRODUCERS
130  */
131 
132 /*
133  * Returns 1 if tracing for the specified category is enabled, otherwise 0
134  */
135 int OSSL_trace_enabled(int category);
136 
137 /*
138  * Wrap a group of tracing output calls.  OSSL_trace_begin() locks tracing and
139  * returns the trace channel associated with the given category, or NULL if no
140  * channel is associated with the category.  OSSL_trace_end() unlocks tracing.
141  *
142  * Usage:
143  *
144  *    BIO *out;
145  *    if ((out = OSSL_trace_begin(category)) != NULL) {
146  *        ...
147  *        BIO_fprintf(out, ...);
148  *        ...
149  *        OSSL_trace_end(category, out);
150  *    }
151  *
152  * See also the convenience macros OSSL_TRACE_BEGIN and OSSL_TRACE_END below.
153  */
154 BIO *OSSL_trace_begin(int category);
155 void OSSL_trace_end(int category, BIO *channel);
156 
157 /*
158  * OSSL_TRACE* Convenience Macros
159  */
160 
161 /*
162  * When the tracing feature is disabled, these macros are defined to
163  * produce dead code, which a good compiler should eliminate.
164  */
165 
166 /*
167  * OSSL_TRACE_BEGIN, OSSL_TRACE_END - Define a Trace Group
168  *
169  * These two macros can be used to create a block which is executed only
170  * if the corresponding trace category is enabled. Inside this block, a
171  * local variable named |trc_out| is defined, which points to the channel
172  * associated with the given trace category.
173  *
174  * Usage: (using 'TLS' as an example category)
175  *
176  *     OSSL_TRACE_BEGIN(TLS) {
177  *
178  *         BIO_fprintf(trc_out, ... );
179  *
180  *     } OSSL_TRACE_END(TLS);
181  *
182  *
183  * This expands to the following code
184  *
185  *     do {
186  *         BIO *trc_out = OSSL_trace_begin(OSSL_TRACE_CATEGORY_TLS);
187  *         if (trc_out != NULL) {
188  *             ...
189  *             BIO_fprintf(trc_out, ...);
190  *         }
191  *         OSSL_trace_end(OSSL_TRACE_CATEGORY_TLS, trc_out);
192  *     } while (0);
193  *
194  * The use of the inner '{...}' group and the trailing ';' is enforced
195  * by the definition of the macros in order to make the code look as much
196  * like C code as possible.
197  *
198  * Before returning from inside the trace block, it is necessary to
199  * call OSSL_TRACE_CANCEL(category).
200  */
201 
202 #if !defined OPENSSL_NO_TRACE && !defined FIPS_MODULE
203 
204 #define OSSL_TRACE_BEGIN(category)                                       \
205     do {                                                                 \
206         BIO *trc_out = OSSL_trace_begin(OSSL_TRACE_CATEGORY_##category); \
207                                                                          \
208         if (trc_out != NULL)
209 
210 #define OSSL_TRACE_END(category)                             \
211     OSSL_trace_end(OSSL_TRACE_CATEGORY_##category, trc_out); \
212     }                                                        \
213     while (0)
214 
215 #define OSSL_TRACE_CANCEL(category) \
216     OSSL_trace_end(OSSL_TRACE_CATEGORY_##category, trc_out)
217 
218 #else
219 
220 #define OSSL_TRACE_BEGIN(category) \
221     do {                           \
222         BIO *trc_out = NULL;       \
223         if (0)
224 
225 #define OSSL_TRACE_END(category) \
226     }                            \
227     while (0)
228 
229 #define OSSL_TRACE_CANCEL(category) \
230     ((void)0)
231 
232 #endif
233 
234 /*
235  * OSSL_TRACE_ENABLED() - Check whether tracing is enabled for |category|
236  *
237  * Usage:
238  *
239  *     if (OSSL_TRACE_ENABLED(TLS)) {
240  *         ...
241  *     }
242  */
243 #if !defined OPENSSL_NO_TRACE && !defined FIPS_MODULE
244 
245 #define OSSL_TRACE_ENABLED(category) \
246     OSSL_trace_enabled(OSSL_TRACE_CATEGORY_##category)
247 
248 #else
249 
250 #define OSSL_TRACE_ENABLED(category) (0)
251 
252 #endif
253 
254 /*
255  * OSSL_TRACE*() - OneShot Trace Macros
256  *
257  * These macros are intended to produce a simple printf-style trace output.
258  * Unfortunately, C90 macros don't support variable arguments, so the
259  * "vararg" OSSL_TRACEV() macro has a rather weird usage pattern:
260  *
261  *    OSSL_TRACEV(category, (trc_out, "format string", ...args...));
262  *
263  * Where 'channel' is the literal symbol of this name, not a variable.
264  * For that reason, it is currently not intended to be used directly,
265  * but only as helper macro for the other oneshot trace macros
266  * OSSL_TRACE(), OSSL_TRACE1(), OSSL_TRACE2(), ...
267  *
268  * Usage:
269  *
270  *    OSSL_TRACE(INIT, "Hello world!\n");
271  *    OSSL_TRACE1(TLS, "The answer is %d\n", 42);
272  *    OSSL_TRACE2(TLS, "The ultimate question to answer %d is '%s'\n",
273  *                42, "What do you get when you multiply six by nine?");
274  */
275 
276 #if !defined OPENSSL_NO_TRACE && !defined FIPS_MODULE
277 
278 #define OSSL_TRACEV(category, args) \
279     OSSL_TRACE_BEGIN(category)      \
280     BIO_printf args;                \
281     OSSL_TRACE_END(category)
282 
283 #else
284 
285 #define OSSL_TRACEV(category, args) ((void)0)
286 
287 #endif
288 
289 #define OSSL_TRACE(category, text) \
290     OSSL_TRACEV(category, (trc_out, "%s", text))
291 
292 #define OSSL_TRACE1(category, format, arg1) \
293     OSSL_TRACEV(category, (trc_out, format, arg1))
294 #define OSSL_TRACE2(category, format, arg1, arg2) \
295     OSSL_TRACEV(category, (trc_out, format, arg1, arg2))
296 #define OSSL_TRACE3(category, format, arg1, arg2, arg3) \
297     OSSL_TRACEV(category, (trc_out, format, arg1, arg2, arg3))
298 #define OSSL_TRACE4(category, format, arg1, arg2, arg3, arg4) \
299     OSSL_TRACEV(category, (trc_out, format, arg1, arg2, arg3, arg4))
300 #define OSSL_TRACE5(category, format, arg1, arg2, arg3, arg4, arg5) \
301     OSSL_TRACEV(category, (trc_out, format, arg1, arg2, arg3, arg4, arg5))
302 #define OSSL_TRACE6(category, format, arg1, arg2, arg3, arg4, arg5, arg6) \
303     OSSL_TRACEV(category, (trc_out, format, arg1, arg2, arg3, arg4, arg5, arg6))
304 #define OSSL_TRACE7(category, format, arg1, arg2, arg3, arg4, arg5, arg6, arg7) \
305     OSSL_TRACEV(category, (trc_out, format, arg1, arg2, arg3, arg4, arg5, arg6, arg7))
306 #define OSSL_TRACE8(category, format, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8) \
307     OSSL_TRACEV(category, (trc_out, format, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8))
308 #define OSSL_TRACE9(category, format, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8, arg9) \
309     OSSL_TRACEV(category, (trc_out, format, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8, arg9))
310 
311 #define OSSL_TRACE_STRING_MAX 80
312 int OSSL_trace_string(BIO *out, int text, int full,
313     const unsigned char *data, size_t size);
314 #define OSSL_TRACE_STRING(category, text, full, data, len) \
315     OSSL_TRACE_BEGIN(category)                             \
316     {                                                      \
317         OSSL_trace_string(trc_out, text, full, data, len); \
318     }                                                      \
319     OSSL_TRACE_END(category)
320 
321 #ifdef __cplusplus
322 }
323 #endif
324 
325 #endif
326