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_NUM 14
55 /* Returns the trace category number for the given |name| */
56 int OSSL_trace_get_category_num(const char *name);
58 /* Returns the trace category name for the given |num| */
59 const char *OSSL_trace_get_category_name(int num);
66 * Enables tracing for the given |category| by providing a BIO sink
67 * as |channel|. If a null pointer is passed as |channel|, an existing
68 * trace channel is removed and tracing for the category is disabled.
70 * Returns 1 on success and 0 on failure
72 int OSSL_trace_set_channel(int category, BIO* channel);
75 * Attach a prefix and a suffix to the given |category|, to be printed at the
76 * beginning and at the end of each trace output group, i.e. when
77 * OSSL_trace_begin() and OSSL_trace_end() are called.
78 * If a null pointer is passed as argument, the existing prefix or suffix is
81 * They return 1 on success and 0 on failure
83 int OSSL_trace_set_prefix(int category, const char *prefix);
84 int OSSL_trace_set_suffix(int category, const char *suffix);
87 * OSSL_trace_cb is the type tracing callback provided by the application.
88 * It MUST return the number of bytes written, or 0 on error (in other words,
89 * it can never write zero bytes).
91 * The |buffer| will always contain text, which may consist of several lines.
92 * The |data| argument points to whatever data was provided by the application
93 * when registering the tracer function.
95 * The |category| number is given, as well as a |cmd| number, described below.
97 typedef size_t (*OSSL_trace_cb)(const char *buffer, size_t count,
98 int category, int cmd, void *data);
100 * Possible |cmd| numbers.
102 # define OSSL_TRACE_CTRL_BEGIN 0
103 # define OSSL_TRACE_CTRL_WRITE 1
104 # define OSSL_TRACE_CTRL_END 2
107 * Enables tracing for the given |category| by creating an internal
108 * trace channel which sends the output to the given |callback|.
109 * If a null pointer is passed as callback, an existing trace channel
110 * is removed and tracing for the category is disabled.
112 * NOTE: OSSL_trace_set_channel() and OSSL_trace_set_callback() are mutually
115 * Returns 1 on success and 0 on failure
117 int OSSL_trace_set_callback(int category, OSSL_trace_cb callback, void *data);
124 * Returns 1 if tracing for the specified category is enabled, otherwise 0
126 int OSSL_trace_enabled(int category);
129 * Wrap a group of tracing output calls. OSSL_trace_begin() locks tracing and
130 * returns the trace channel associated with the given category, or NULL if no
131 * channel is associated with the category. OSSL_trace_end() unlocks tracing.
136 * if ((out = OSSL_trace_begin(category)) != NULL) {
138 * BIO_fprintf(out, ...);
140 * OSSL_trace_end(category, out);
143 * See also the convenience macros OSSL_TRACE_BEGIN and OSSL_TRACE_END below.
145 BIO *OSSL_trace_begin(int category);
146 void OSSL_trace_end(int category, BIO *channel);
149 * OSSL_TRACE* Convenience Macros
153 * When the tracing feature is disabled, these macros are defined to
154 * produce dead code, which a good compiler should eliminate.
158 * OSSL_TRACE_BEGIN, OSSL_TRACE_END - Define a Trace Group
160 * These two macros can be used to create a block which is executed only
161 * if the corresponding trace category is enabled. Inside this block, a
162 * local variable named |trc_out| is defined, which points to the channel
163 * associated with the given trace category.
165 * Usage: (using 'TLS' as an example category)
167 * OSSL_TRACE_BEGIN(TLS) {
169 * BIO_fprintf(trc_out, ... );
171 * } OSSL_TRACE_END(TLS);
174 * This expands to the following code
177 * BIO *trc_out = OSSL_trace_begin(OSSL_TRACE_CATEGORY_TLS);
178 * if (trc_out != NULL) {
180 * BIO_fprintf(trc_out, ...);
182 * OSSL_trace_end(OSSL_TRACE_CATEGORY_TLS, trc_out);
185 * The use of the inner '{...}' group and the trailing ';' is enforced
186 * by the definition of the macros in order to make the code look as much
187 * like C code as possible.
189 * Before returning from inside the trace block, it is necessary to
190 * call OSSL_TRACE_CANCEL(category).
193 # ifndef OPENSSL_NO_TRACE
195 # define OSSL_TRACE_BEGIN(category) \
197 BIO *trc_out = OSSL_trace_begin(OSSL_TRACE_CATEGORY_##category); \
201 # define OSSL_TRACE_END(category) \
202 OSSL_trace_end(OSSL_TRACE_CATEGORY_##category, trc_out); \
205 # define OSSL_TRACE_CANCEL(category) \
206 OSSL_trace_end(OSSL_TRACE_CATEGORY_##category, trc_out) \
210 # define OSSL_TRACE_BEGIN(category) \
212 BIO *trc_out = NULL; \
215 # define OSSL_TRACE_END(category) \
218 # define OSSL_TRACE_CANCEL(category) \
224 * OSSL_TRACE_ENABLED() - Check whether tracing is enabled for |category|
228 * if (OSSL_TRACE_ENABLED(TLS)) {
232 # ifndef OPENSSL_NO_TRACE
234 # define OSSL_TRACE_ENABLED(category) \
235 OSSL_trace_enabled(OSSL_TRACE_CATEGORY_##category)
239 # define OSSL_TRACE_ENABLED(category) (0)
244 * OSSL_TRACE*() - OneShot Trace Macros
246 * These macros are intended to produce a simple printf-style trace output.
247 * Unfortunately, C90 macros don't support variable arguments, so the
248 * "vararg" OSSL_TRACEV() macro has a rather weird usage pattern:
250 * OSSL_TRACEV(category, (trc_out, "format string", ...args...));
252 * Where 'channel' is the literal symbol of this name, not a variable.
253 * For that reason, it is currently not intended to be used directly,
254 * but only as helper macro for the other oneshot trace macros
255 * OSSL_TRACE(), OSSL_TRACE1(), OSSL_TRACE2(), ...
259 * OSSL_TRACE(INIT, "Hello world!\n");
260 * OSSL_TRACE1(TLS, "The answer is %d\n", 42);
261 * OSSL_TRACE2(TLS, "The ultimate question to answer %d is '%s'\n",
262 * 42, "What do you get when you multiply six by nine?");
265 # define OSSL_TRACEV(category, args) \
266 OSSL_TRACE_BEGIN(category) \
268 OSSL_TRACE_END(category)
270 # define OSSL_TRACE(category, text) \
271 OSSL_TRACEV(category, (trc_out, "%s", text))
273 # define OSSL_TRACE1(category, format, arg1) \
274 OSSL_TRACEV(category, (trc_out, format, arg1))
275 # define OSSL_TRACE2(category, format, arg1, arg2) \
276 OSSL_TRACEV(category, (trc_out, format, arg1, arg2))
277 # define OSSL_TRACE3(category, format, arg1, arg2, arg3) \
278 OSSL_TRACEV(category, (trc_out, format, arg1, arg2, arg3))
279 # define OSSL_TRACE4(category, format, arg1, arg2, arg3, arg4) \
280 OSSL_TRACEV(category, (trc_out, format, arg1, arg2, arg3, arg4))
281 # define OSSL_TRACE5(category, format, arg1, arg2, arg3, arg4, arg5) \
282 OSSL_TRACEV(category, (trc_out, format, arg1, arg2, arg3, arg4, arg5))
283 # define OSSL_TRACE6(category, format, arg1, arg2, arg3, arg4, arg5, arg6) \
284 OSSL_TRACEV(category, (trc_out, format, arg1, arg2, arg3, arg4, arg5, arg6))
285 # define OSSL_TRACE7(category, format, arg1, arg2, arg3, arg4, arg5, arg6, arg7) \
286 OSSL_TRACEV(category, (trc_out, format, arg1, arg2, arg3, arg4, arg5, arg6, arg7))
287 # define OSSL_TRACE8(category, format, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8) \
288 OSSL_TRACEV(category, (trc_out, format, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8))
289 # define OSSL_TRACE9(category, format, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8) \
290 OSSL_TRACEV(category, (trc_out, format, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8, arg9))