2 * Copyright 2019 The OpenSSL Project Authors. All Rights Reserved.
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
10 #ifndef OPENSSL_TRACE_H
11 # define OPENSSL_TRACE_H
15 # include <openssl/bio.h>
26 * The trace messages of the OpenSSL libraries are organized into different
27 * categories. For every trace category, the application can register a separate
28 * tracer callback. When a callback is registered, a so called trace channel is
29 * created for this category. This channel consists essentially of an internal
30 * BIO which sends all trace output it receives to the registered application
33 * The ALL category can be used as a fallback category to register a single
34 * channel which receives the output from all categories. However, if the
35 * application intends to print the trace channel name in the line prefix,
36 * it is better to register channels for all categories separately.
37 * (This is how the openssl application does it.)
39 # define OSSL_TRACE_CATEGORY_ALL 0 /* The fallback */
40 # define OSSL_TRACE_CATEGORY_TRACE 1
41 # define OSSL_TRACE_CATEGORY_INIT 2
42 # define OSSL_TRACE_CATEGORY_TLS 3
43 # define OSSL_TRACE_CATEGORY_TLS_CIPHER 4
44 # define OSSL_TRACE_CATEGORY_CONF 5
45 # define OSSL_TRACE_CATEGORY_ENGINE_TABLE 6
46 # define OSSL_TRACE_CATEGORY_ENGINE_REF_COUNT 7
47 # define OSSL_TRACE_CATEGORY_PKCS5V2 8
48 # define OSSL_TRACE_CATEGORY_PKCS12_KEYGEN 9
49 # define OSSL_TRACE_CATEGORY_PKCS12_DECRYPT 10
50 # define OSSL_TRACE_CATEGORY_X509V3_POLICY 11
51 # define OSSL_TRACE_CATEGORY_BN_CTX 12
52 # define OSSL_TRACE_CATEGORY_CMP 13
53 # define OSSL_TRACE_CATEGORY_STORE 14
54 # define OSSL_TRACE_CATEGORY_NUM 15
56 /* Returns the trace category number for the given |name| */
57 int OSSL_trace_get_category_num(const char *name);
59 /* Returns the trace category name for the given |num| */
60 const char *OSSL_trace_get_category_name(int num);
67 * Enables tracing for the given |category| by providing a BIO sink
68 * as |channel|. If a null pointer is passed as |channel|, an existing
69 * trace channel is removed and tracing for the category is disabled.
71 * Returns 1 on success and 0 on failure
73 int OSSL_trace_set_channel(int category, BIO* channel);
76 * Attach a prefix and a suffix to the given |category|, to be printed at the
77 * beginning and at the end of each trace output group, i.e. when
78 * OSSL_trace_begin() and OSSL_trace_end() are called.
79 * If a null pointer is passed as argument, the existing prefix or suffix is
82 * They return 1 on success and 0 on failure
84 int OSSL_trace_set_prefix(int category, const char *prefix);
85 int OSSL_trace_set_suffix(int category, const char *suffix);
88 * OSSL_trace_cb is the type tracing callback provided by the application.
89 * It MUST return the number of bytes written, or 0 on error (in other words,
90 * it can never write zero bytes).
92 * The |buffer| will always contain text, which may consist of several lines.
93 * The |data| argument points to whatever data was provided by the application
94 * when registering the tracer function.
96 * The |category| number is given, as well as a |cmd| number, described below.
98 typedef size_t (*OSSL_trace_cb)(const char *buffer, size_t count,
99 int category, int cmd, void *data);
101 * Possible |cmd| numbers.
103 # define OSSL_TRACE_CTRL_BEGIN 0
104 # define OSSL_TRACE_CTRL_WRITE 1
105 # define OSSL_TRACE_CTRL_END 2
108 * Enables tracing for the given |category| by creating an internal
109 * trace channel which sends the output to the given |callback|.
110 * If a null pointer is passed as callback, an existing trace channel
111 * is removed and tracing for the category is disabled.
113 * NOTE: OSSL_trace_set_channel() and OSSL_trace_set_callback() are mutually
116 * Returns 1 on success and 0 on failure
118 int OSSL_trace_set_callback(int category, OSSL_trace_cb callback, void *data);
125 * Returns 1 if tracing for the specified category is enabled, otherwise 0
127 int OSSL_trace_enabled(int category);
130 * Wrap a group of tracing output calls. OSSL_trace_begin() locks tracing and
131 * returns the trace channel associated with the given category, or NULL if no
132 * channel is associated with the category. OSSL_trace_end() unlocks tracing.
137 * if ((out = OSSL_trace_begin(category)) != NULL) {
139 * BIO_fprintf(out, ...);
141 * OSSL_trace_end(category, out);
144 * See also the convenience macros OSSL_TRACE_BEGIN and OSSL_TRACE_END below.
146 BIO *OSSL_trace_begin(int category);
147 void OSSL_trace_end(int category, BIO *channel);
150 * OSSL_TRACE* Convenience Macros
154 * When the tracing feature is disabled, these macros are defined to
155 * produce dead code, which a good compiler should eliminate.
159 * OSSL_TRACE_BEGIN, OSSL_TRACE_END - Define a Trace Group
161 * These two macros can be used to create a block which is executed only
162 * if the corresponding trace category is enabled. Inside this block, a
163 * local variable named |trc_out| is defined, which points to the channel
164 * associated with the given trace category.
166 * Usage: (using 'TLS' as an example category)
168 * OSSL_TRACE_BEGIN(TLS) {
170 * BIO_fprintf(trc_out, ... );
172 * } OSSL_TRACE_END(TLS);
175 * This expands to the following code
178 * BIO *trc_out = OSSL_trace_begin(OSSL_TRACE_CATEGORY_TLS);
179 * if (trc_out != NULL) {
181 * BIO_fprintf(trc_out, ...);
183 * OSSL_trace_end(OSSL_TRACE_CATEGORY_TLS, trc_out);
186 * The use of the inner '{...}' group and the trailing ';' is enforced
187 * by the definition of the macros in order to make the code look as much
188 * like C code as possible.
190 * Before returning from inside the trace block, it is necessary to
191 * call OSSL_TRACE_CANCEL(category).
194 # ifndef OPENSSL_NO_TRACE
196 # define OSSL_TRACE_BEGIN(category) \
198 BIO *trc_out = OSSL_trace_begin(OSSL_TRACE_CATEGORY_##category); \
202 # define OSSL_TRACE_END(category) \
203 OSSL_trace_end(OSSL_TRACE_CATEGORY_##category, trc_out); \
206 # define OSSL_TRACE_CANCEL(category) \
207 OSSL_trace_end(OSSL_TRACE_CATEGORY_##category, trc_out) \
211 # define OSSL_TRACE_BEGIN(category) \
213 BIO *trc_out = NULL; \
216 # define OSSL_TRACE_END(category) \
219 # define OSSL_TRACE_CANCEL(category) \
225 * OSSL_TRACE_ENABLED() - Check whether tracing is enabled for |category|
229 * if (OSSL_TRACE_ENABLED(TLS)) {
233 # ifndef OPENSSL_NO_TRACE
235 # define OSSL_TRACE_ENABLED(category) \
236 OSSL_trace_enabled(OSSL_TRACE_CATEGORY_##category)
240 # define OSSL_TRACE_ENABLED(category) (0)
245 * OSSL_TRACE*() - OneShot Trace Macros
247 * These macros are intended to produce a simple printf-style trace output.
248 * Unfortunately, C90 macros don't support variable arguments, so the
249 * "vararg" OSSL_TRACEV() macro has a rather weird usage pattern:
251 * OSSL_TRACEV(category, (trc_out, "format string", ...args...));
253 * Where 'channel' is the literal symbol of this name, not a variable.
254 * For that reason, it is currently not intended to be used directly,
255 * but only as helper macro for the other oneshot trace macros
256 * OSSL_TRACE(), OSSL_TRACE1(), OSSL_TRACE2(), ...
260 * OSSL_TRACE(INIT, "Hello world!\n");
261 * OSSL_TRACE1(TLS, "The answer is %d\n", 42);
262 * OSSL_TRACE2(TLS, "The ultimate question to answer %d is '%s'\n",
263 * 42, "What do you get when you multiply six by nine?");
266 # define OSSL_TRACEV(category, args) \
267 OSSL_TRACE_BEGIN(category) \
269 OSSL_TRACE_END(category)
271 # define OSSL_TRACE(category, text) \
272 OSSL_TRACEV(category, (trc_out, "%s", text))
274 # define OSSL_TRACE1(category, format, arg1) \
275 OSSL_TRACEV(category, (trc_out, format, arg1))
276 # define OSSL_TRACE2(category, format, arg1, arg2) \
277 OSSL_TRACEV(category, (trc_out, format, arg1, arg2))
278 # define OSSL_TRACE3(category, format, arg1, arg2, arg3) \
279 OSSL_TRACEV(category, (trc_out, format, arg1, arg2, arg3))
280 # define OSSL_TRACE4(category, format, arg1, arg2, arg3, arg4) \
281 OSSL_TRACEV(category, (trc_out, format, arg1, arg2, arg3, arg4))
282 # define OSSL_TRACE5(category, format, arg1, arg2, arg3, arg4, arg5) \
283 OSSL_TRACEV(category, (trc_out, format, arg1, arg2, arg3, arg4, arg5))
284 # define OSSL_TRACE6(category, format, arg1, arg2, arg3, arg4, arg5, arg6) \
285 OSSL_TRACEV(category, (trc_out, format, arg1, arg2, arg3, arg4, arg5, arg6))
286 # define OSSL_TRACE7(category, format, arg1, arg2, arg3, arg4, arg5, arg6, arg7) \
287 OSSL_TRACEV(category, (trc_out, format, arg1, arg2, arg3, arg4, arg5, arg6, arg7))
288 # define OSSL_TRACE8(category, format, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8) \
289 OSSL_TRACEV(category, (trc_out, format, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8))
290 # define OSSL_TRACE9(category, format, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8) \
291 OSSL_TRACEV(category, (trc_out, format, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8, arg9))