/*

 * Copyright 2019 The OpenSSL Project Authors. All Rights Reserved.

 *

 * Licensed under the Apache License 2.0 (the "License").  You may not use

 * this file except in compliance with the License.  You can obtain a copy

 * in the file LICENSE in the source distribution or at

 * https://www.openssl.org/source/license.html

 */

#ifndef OPENSSL_TRACE_H

# define OPENSSL_TRACE_H

# include <stdarg.h>

# include <openssl/bio.h>

# ifdef  __cplusplus

extern "C" {

# endif

/*

 * TRACE CATEGORIES

 */

/*

 * The trace messages of the OpenSSL libraries are organized into different

 * categories. For every trace category, the application can register a separate

 * tracer callback. When a callback is registered, a so called trace channel is

 * created for this category. This channel consists essentially of an internal

 * BIO which sends all trace output it receives to the registered application

 * callback.

 *

 * The ALL category can be used as a fallback category to register a single

 * channel which receives the output from all categories. However, if the

 * application intends to print the trace channel name in the line prefix,

 * it is better to register channels for all categories separately.

 * (This is how the openssl application does it.)

 */

# define OSSL_TRACE_CATEGORY_ALL                 0 /* The fallback */

# define OSSL_TRACE_CATEGORY_TRACE               1

# define OSSL_TRACE_CATEGORY_INIT                2

# define OSSL_TRACE_CATEGORY_TLS                 3

# define OSSL_TRACE_CATEGORY_TLS_CIPHER          4

# define OSSL_TRACE_CATEGORY_CONF                5

# define OSSL_TRACE_CATEGORY_ENGINE_TABLE        6

# define OSSL_TRACE_CATEGORY_ENGINE_REF_COUNT    7

# define OSSL_TRACE_CATEGORY_PKCS5V2             8

# define OSSL_TRACE_CATEGORY_PKCS12_KEYGEN       9

# define OSSL_TRACE_CATEGORY_PKCS12_DECRYPT     10

# define OSSL_TRACE_CATEGORY_X509V3_POLICY      11

# define OSSL_TRACE_CATEGORY_BN_CTX             12

# define OSSL_TRACE_CATEGORY_CMP                13

# define OSSL_TRACE_CATEGORY_STORE              14

# define OSSL_TRACE_CATEGORY_NUM                15

/* Returns the trace category number for the given |name| */

int OSSL_trace_get_category_num(const char *name);

/* Returns the trace category name for the given |num| */

const char *OSSL_trace_get_category_name(int num);

/*

 * TRACE CONSUMERS

 */

/*

 * Enables tracing for the given |category| by providing a BIO sink

 * as |channel|. If a null pointer is passed as |channel|, an existing

 * trace channel is removed and tracing for the category is disabled.

 *

 * Returns 1 on success and 0 on failure

 */

int OSSL_trace_set_channel(int category, BIO* channel);

/*

 * Attach a prefix and a suffix to the given |category|, to be printed at the

 * beginning and at the end of each trace output group, i.e. when

 * OSSL_trace_begin() and OSSL_trace_end() are called.

 * If a null pointer is passed as argument, the existing prefix or suffix is

 * removed.

 *

 * They return 1 on success and 0 on failure

 */

int OSSL_trace_set_prefix(int category, const char *prefix);

int OSSL_trace_set_suffix(int category, const char *suffix);

/*

 * OSSL_trace_cb is the type tracing callback provided by the application.

 * It MUST return the number of bytes written, or 0 on error (in other words,

 * it can never write zero bytes).

 *

 * The |buffer| will always contain text, which may consist of several lines.

 * The |data| argument points to whatever data was provided by the application

 * when registering the tracer function.

 *

 * The |category| number is given, as well as a |cmd| number, described below.

 */

typedef size_t (*OSSL_trace_cb)(const char *buffer, size_t count,

                                int category, int cmd, void *data);

/*

 * Possible |cmd| numbers.

 */

# define OSSL_TRACE_CTRL_BEGIN  0

# define OSSL_TRACE_CTRL_WRITE  1

# define OSSL_TRACE_CTRL_END    2

/*

 * Enables tracing for the given |category| by creating an internal

 * trace channel which sends the output to the given |callback|.

 * If a null pointer is passed as callback, an existing trace channel

 * is removed and tracing for the category is disabled.

 *

 * NOTE: OSSL_trace_set_channel() and OSSL_trace_set_callback() are mutually

 *       exclusive.

 *

 * Returns 1 on success and 0 on failure

 */

int OSSL_trace_set_callback(int category, OSSL_trace_cb callback, void *data);

/*

 * TRACE PRODUCERS

 */

/*

 * Returns 1 if tracing for the specified category is enabled, otherwise 0

 */

int OSSL_trace_enabled(int category);

/*

 * Wrap a group of tracing output calls.  OSSL_trace_begin() locks tracing and

 * returns the trace channel associated with the given category, or NULL if no

 * channel is associated with the category.  OSSL_trace_end() unlocks tracing.

 *

 * Usage:

 *

 *    BIO *out;

 *    if ((out = OSSL_trace_begin(category)) != NULL) {

 *        ...

 *        BIO_fprintf(out, ...);

 *        ...

 *        OSSL_trace_end(category, out);

 *    }

 *

 * See also the convenience macros OSSL_TRACE_BEGIN and OSSL_TRACE_END below.

 */

BIO *OSSL_trace_begin(int category);

void OSSL_trace_end(int category, BIO *channel);

/*

 * OSSL_TRACE* Convenience Macros

 */

/*

 * When the tracing feature is disabled, these macros are defined to

 * produce dead code, which a good compiler should eliminate.

 */

/*

 * OSSL_TRACE_BEGIN, OSSL_TRACE_END - Define a Trace Group

 *

 * These two macros can be used to create a block which is executed only

 * if the corresponding trace category is enabled. Inside this block, a

 * local variable named |trc_out| is defined, which points to the channel

 * associated with the given trace category.

 *

 * Usage: (using 'TLS' as an example category)

 *

 *     OSSL_TRACE_BEGIN(TLS) {

 *

 *         BIO_fprintf(trc_out, ... );

 *

 *     } OSSL_TRACE_END(TLS);

 *

 *

 * This expands to the following code

 *

 *     do {

 *         BIO *trc_out = OSSL_trace_begin(OSSL_TRACE_CATEGORY_TLS);

 *         if (trc_out != NULL) {

 *             ...

 *             BIO_fprintf(trc_out, ...);

 *         }

 *         OSSL_trace_end(OSSL_TRACE_CATEGORY_TLS, trc_out);

 *     } while (0);

 *

 * The use of the inner '{...}' group and the trailing ';' is enforced

 * by the definition of the macros in order to make the code look as much

 * like C code as possible.

 *

 * Before returning from inside the trace block, it is necessary to

 * call OSSL_TRACE_CANCEL(category).

 */

# ifndef OPENSSL_NO_TRACE

#  define OSSL_TRACE_BEGIN(category) \

    do { \

        BIO *trc_out = OSSL_trace_begin(OSSL_TRACE_CATEGORY_##category); \

 \

        if (trc_out != NULL)

#  define OSSL_TRACE_END(category) \

        OSSL_trace_end(OSSL_TRACE_CATEGORY_##category, trc_out); \

    } while (0)

#  define OSSL_TRACE_CANCEL(category) \

        OSSL_trace_end(OSSL_TRACE_CATEGORY_##category, trc_out) \

# else

#  define OSSL_TRACE_BEGIN(category)           \

    do {                                        \

        BIO *trc_out = NULL;                    \

        if (0)

#  define OSSL_TRACE_END(category)             \

    } while(0)

#  define OSSL_TRACE_CANCEL(category)          \

    ((void)0)

# endif

/*

 * OSSL_TRACE_ENABLED() - Check whether tracing is enabled for |category|

 *

 * Usage:

 *

 *     if (OSSL_TRACE_ENABLED(TLS)) {

 *         ...

 *     }

 */

# ifndef OPENSSL_NO_TRACE

#  define OSSL_TRACE_ENABLED(category) \

    OSSL_trace_enabled(OSSL_TRACE_CATEGORY_##category)

# else

#  define OSSL_TRACE_ENABLED(category) (0)

# endif

/*

 * OSSL_TRACE*() - OneShot Trace Macros

 *

 * These macros are intended to produce a simple printf-style trace output.

 * Unfortunately, C90 macros don't support variable arguments, so the

 * "vararg" OSSL_TRACEV() macro has a rather weird usage pattern:

 *

 *    OSSL_TRACEV(category, (trc_out, "format string", ...args...));

 *

 * Where 'channel' is the literal symbol of this name, not a variable.

 * For that reason, it is currently not intended to be used directly,

 * but only as helper macro for the other oneshot trace macros

 * OSSL_TRACE(), OSSL_TRACE1(), OSSL_TRACE2(), ...

 *

 * Usage:

 *

 *    OSSL_TRACE(INIT, "Hello world!\n");

 *    OSSL_TRACE1(TLS, "The answer is %d\n", 42);

 *    OSSL_TRACE2(TLS, "The ultimate question to answer %d is '%s'\n",

 *                42, "What do you get when you multiply six by nine?");

 */

# define OSSL_TRACEV(category, args) \

    OSSL_TRACE_BEGIN(category) \

        BIO_printf args; \

    OSSL_TRACE_END(category)

# define OSSL_TRACE(category, text) \

    OSSL_TRACEV(category, (trc_out, "%s", text))

# define OSSL_TRACE1(category, format, arg1) \

    OSSL_TRACEV(category, (trc_out, format, arg1))

# define OSSL_TRACE2(category, format, arg1, arg2) \

    OSSL_TRACEV(category, (trc_out, format, arg1, arg2))

# define OSSL_TRACE3(category, format, arg1, arg2, arg3) \

    OSSL_TRACEV(category, (trc_out, format, arg1, arg2, arg3))

# define OSSL_TRACE4(category, format, arg1, arg2, arg3, arg4) \

    OSSL_TRACEV(category, (trc_out, format, arg1, arg2, arg3, arg4))

# define OSSL_TRACE5(category, format, arg1, arg2, arg3, arg4, arg5) \

    OSSL_TRACEV(category, (trc_out, format, arg1, arg2, arg3, arg4, arg5))

# define OSSL_TRACE6(category, format, arg1, arg2, arg3, arg4, arg5, arg6) \

    OSSL_TRACEV(category, (trc_out, format, arg1, arg2, arg3, arg4, arg5, arg6))

# define OSSL_TRACE7(category, format, arg1, arg2, arg3, arg4, arg5, arg6, arg7) \

    OSSL_TRACEV(category, (trc_out, format, arg1, arg2, arg3, arg4, arg5, arg6, arg7))

# define OSSL_TRACE8(category, format, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8) \

    OSSL_TRACEV(category, (trc_out, format, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8))

# define OSSL_TRACE9(category, format, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8) \

    OSSL_TRACEV(category, (trc_out, format, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8, arg9))

# ifdef  __cplusplus

}

# endif

#endif