xref: /third_party/mbedtls/library/debug.c (revision a8e1175b)
1/*
2 *  Debugging routines
3 *
4 *  Copyright The Mbed TLS Contributors
5 *  SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
6 */
7
8#include "common.h"
9
10#if defined(MBEDTLS_DEBUG_C)
11
12#include "mbedtls/platform.h"
13
14#include "debug_internal.h"
15#include "mbedtls/error.h"
16
17#include <stdarg.h>
18#include <stdio.h>
19#include <string.h>
20
21/* DEBUG_BUF_SIZE must be at least 2 */
22#define DEBUG_BUF_SIZE      512
23
24static int debug_threshold = 0;
25
26void mbedtls_debug_set_threshold(int threshold)
27{
28    debug_threshold = threshold;
29}
30
31/*
32 * All calls to f_dbg must be made via this function
33 */
34static inline void debug_send_line(const mbedtls_ssl_context *ssl, int level,
35                                   const char *file, int line,
36                                   const char *str)
37{
38    /*
39     * If in a threaded environment, we need a thread identifier.
40     * Since there is no portable way to get one, use the address of the ssl
41     * context instead, as it shouldn't be shared between threads.
42     */
43#if defined(MBEDTLS_THREADING_C)
44    char idstr[20 + DEBUG_BUF_SIZE]; /* 0x + 16 nibbles + ': ' */
45    mbedtls_snprintf(idstr, sizeof(idstr), "%p: %s", (void *) ssl, str);
46    ssl->conf->f_dbg(ssl->conf->p_dbg, level, file, line, idstr);
47#else
48    ssl->conf->f_dbg(ssl->conf->p_dbg, level, file, line, str);
49#endif
50}
51
52MBEDTLS_PRINTF_ATTRIBUTE(5, 6)
53void mbedtls_debug_print_msg(const mbedtls_ssl_context *ssl, int level,
54                             const char *file, int line,
55                             const char *format, ...)
56{
57    va_list argp;
58    char str[DEBUG_BUF_SIZE];
59    int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
60
61    MBEDTLS_STATIC_ASSERT(DEBUG_BUF_SIZE >= 2, "DEBUG_BUF_SIZE too small");
62
63    if (NULL == ssl              ||
64        NULL == ssl->conf        ||
65        NULL == ssl->conf->f_dbg ||
66        level > debug_threshold) {
67        return;
68    }
69
70    va_start(argp, format);
71    ret = mbedtls_vsnprintf(str, DEBUG_BUF_SIZE, format, argp);
72    va_end(argp);
73
74    if (ret < 0) {
75        ret = 0;
76    } else {
77        if (ret >= DEBUG_BUF_SIZE - 1) {
78            ret = DEBUG_BUF_SIZE - 2;
79        }
80    }
81    str[ret]     = '\n';
82    str[ret + 1] = '\0';
83
84    debug_send_line(ssl, level, file, line, str);
85}
86
87void mbedtls_debug_print_ret(const mbedtls_ssl_context *ssl, int level,
88                             const char *file, int line,
89                             const char *text, int ret)
90{
91    char str[DEBUG_BUF_SIZE];
92
93    if (NULL == ssl              ||
94        NULL == ssl->conf        ||
95        NULL == ssl->conf->f_dbg ||
96        level > debug_threshold) {
97        return;
98    }
99
100    /*
101     * With non-blocking I/O and examples that just retry immediately,
102     * the logs would be quickly flooded with WANT_READ, so ignore that.
103     * Don't ignore WANT_WRITE however, since it is usually rare.
104     */
105    if (ret == MBEDTLS_ERR_SSL_WANT_READ) {
106        return;
107    }
108
109    mbedtls_snprintf(str, sizeof(str), "%s() returned %d (-0x%04x)\n",
110                     text, ret, (unsigned int) -ret);
111
112    debug_send_line(ssl, level, file, line, str);
113}
114
115void mbedtls_debug_print_buf(const mbedtls_ssl_context *ssl, int level,
116                             const char *file, int line, const char *text,
117                             const unsigned char *buf, size_t len)
118{
119    char str[DEBUG_BUF_SIZE];
120    char txt[17];
121    size_t i, idx = 0;
122
123    if (NULL == ssl              ||
124        NULL == ssl->conf        ||
125        NULL == ssl->conf->f_dbg ||
126        level > debug_threshold) {
127        return;
128    }
129
130    mbedtls_snprintf(str + idx, sizeof(str) - idx, "dumping '%s' (%u bytes)\n",
131                     text, (unsigned int) len);
132
133    debug_send_line(ssl, level, file, line, str);
134
135    memset(txt, 0, sizeof(txt));
136    for (i = 0; i < len; i++) {
137        if (i >= 4096) {
138            break;
139        }
140
141        if (i % 16 == 0) {
142            if (i > 0) {
143                mbedtls_snprintf(str + idx, sizeof(str) - idx, "  %s\n", txt);
144                debug_send_line(ssl, level, file, line, str);
145
146                idx = 0;
147                memset(txt, 0, sizeof(txt));
148            }
149
150            idx += mbedtls_snprintf(str + idx, sizeof(str) - idx, "%04x: ",
151                                    (unsigned int) i);
152
153        }
154
155        idx += mbedtls_snprintf(str + idx, sizeof(str) - idx, " %02x",
156                                (unsigned int) buf[i]);
157        txt[i % 16] = (buf[i] > 31 && buf[i] < 127) ? buf[i] : '.';
158    }
159
160    if (len > 0) {
161        for (/* i = i */; i % 16 != 0; i++) {
162            idx += mbedtls_snprintf(str + idx, sizeof(str) - idx, "   ");
163        }
164
165        mbedtls_snprintf(str + idx, sizeof(str) - idx, "  %s\n", txt);
166        debug_send_line(ssl, level, file, line, str);
167    }
168}
169
170#if defined(MBEDTLS_ECP_LIGHT)
171void mbedtls_debug_print_ecp(const mbedtls_ssl_context *ssl, int level,
172                             const char *file, int line,
173                             const char *text, const mbedtls_ecp_point *X)
174{
175    char str[DEBUG_BUF_SIZE];
176
177    if (NULL == ssl              ||
178        NULL == ssl->conf        ||
179        NULL == ssl->conf->f_dbg ||
180        level > debug_threshold) {
181        return;
182    }
183
184    mbedtls_snprintf(str, sizeof(str), "%s(X)", text);
185    mbedtls_debug_print_mpi(ssl, level, file, line, str, &X->X);
186
187    mbedtls_snprintf(str, sizeof(str), "%s(Y)", text);
188    mbedtls_debug_print_mpi(ssl, level, file, line, str, &X->Y);
189}
190#endif /* MBEDTLS_ECP_LIGHT */
191
192#if defined(MBEDTLS_PK_USE_PSA_EC_DATA)
193static void mbedtls_debug_print_ec_coord(const mbedtls_ssl_context *ssl, int level,
194                                         const char *file, int line, const char *text,
195                                         const unsigned char *buf, size_t len)
196{
197    char str[DEBUG_BUF_SIZE];
198    size_t i, idx = 0;
199
200    mbedtls_snprintf(str + idx, sizeof(str) - idx, "value of '%s' (%u bits) is:\n",
201                     text, (unsigned int) len * 8);
202
203    debug_send_line(ssl, level, file, line, str);
204
205    for (i = 0; i < len; i++) {
206        if (i >= 4096) {
207            break;
208        }
209
210        if (i % 16 == 0) {
211            if (i > 0) {
212                mbedtls_snprintf(str + idx, sizeof(str) - idx, "\n");
213                debug_send_line(ssl, level, file, line, str);
214
215                idx = 0;
216            }
217        }
218
219        idx += mbedtls_snprintf(str + idx, sizeof(str) - idx, " %02x",
220                                (unsigned int) buf[i]);
221    }
222
223    if (len > 0) {
224        for (/* i = i */; i % 16 != 0; i++) {
225            idx += mbedtls_snprintf(str + idx, sizeof(str) - idx, "   ");
226        }
227
228        mbedtls_snprintf(str + idx, sizeof(str) - idx, "\n");
229        debug_send_line(ssl, level, file, line, str);
230    }
231}
232
233void mbedtls_debug_print_psa_ec(const mbedtls_ssl_context *ssl, int level,
234                                const char *file, int line,
235                                const char *text, const mbedtls_pk_context *pk)
236{
237    char str[DEBUG_BUF_SIZE];
238    const uint8_t *coord_start;
239    size_t coord_len;
240
241    if (NULL == ssl              ||
242        NULL == ssl->conf        ||
243        NULL == ssl->conf->f_dbg ||
244        level > debug_threshold) {
245        return;
246    }
247
248    /* For the description of pk->pk_raw content please refer to the description
249     * psa_export_public_key() function. */
250    coord_len = (pk->pub_raw_len - 1)/2;
251
252    /* X coordinate */
253    coord_start = pk->pub_raw + 1;
254    mbedtls_snprintf(str, sizeof(str), "%s(X)", text);
255    mbedtls_debug_print_ec_coord(ssl, level, file, line, str, coord_start, coord_len);
256
257    /* Y coordinate */
258    coord_start = coord_start + coord_len;
259    mbedtls_snprintf(str, sizeof(str), "%s(Y)", text);
260    mbedtls_debug_print_ec_coord(ssl, level, file, line, str, coord_start, coord_len);
261}
262#endif /* MBEDTLS_PK_USE_PSA_EC_DATA */
263
264#if defined(MBEDTLS_BIGNUM_C)
265void mbedtls_debug_print_mpi(const mbedtls_ssl_context *ssl, int level,
266                             const char *file, int line,
267                             const char *text, const mbedtls_mpi *X)
268{
269    char str[DEBUG_BUF_SIZE];
270    size_t bitlen;
271    size_t idx = 0;
272
273    if (NULL == ssl              ||
274        NULL == ssl->conf        ||
275        NULL == ssl->conf->f_dbg ||
276        NULL == X                ||
277        level > debug_threshold) {
278        return;
279    }
280
281    bitlen = mbedtls_mpi_bitlen(X);
282
283    mbedtls_snprintf(str, sizeof(str), "value of '%s' (%u bits) is:\n",
284                     text, (unsigned) bitlen);
285    debug_send_line(ssl, level, file, line, str);
286
287    if (bitlen == 0) {
288        str[0] = ' '; str[1] = '0'; str[2] = '0';
289        idx = 3;
290    } else {
291        int n;
292        for (n = (int) ((bitlen - 1) / 8); n >= 0; n--) {
293            size_t limb_offset = n / sizeof(mbedtls_mpi_uint);
294            size_t offset_in_limb = n % sizeof(mbedtls_mpi_uint);
295            unsigned char octet =
296                (X->p[limb_offset] >> (offset_in_limb * 8)) & 0xff;
297            mbedtls_snprintf(str + idx, sizeof(str) - idx, " %02x", octet);
298            idx += 3;
299            /* Wrap lines after 16 octets that each take 3 columns */
300            if (idx >= 3 * 16) {
301                mbedtls_snprintf(str + idx, sizeof(str) - idx, "\n");
302                debug_send_line(ssl, level, file, line, str);
303                idx = 0;
304            }
305        }
306    }
307
308    if (idx != 0) {
309        mbedtls_snprintf(str + idx, sizeof(str) - idx, "\n");
310        debug_send_line(ssl, level, file, line, str);
311    }
312}
313#endif /* MBEDTLS_BIGNUM_C */
314
315#if defined(MBEDTLS_X509_CRT_PARSE_C) && !defined(MBEDTLS_X509_REMOVE_INFO)
316static void debug_print_pk(const mbedtls_ssl_context *ssl, int level,
317                           const char *file, int line,
318                           const char *text, const mbedtls_pk_context *pk)
319{
320    size_t i;
321    mbedtls_pk_debug_item items[MBEDTLS_PK_DEBUG_MAX_ITEMS];
322    char name[16];
323
324    memset(items, 0, sizeof(items));
325
326    if (mbedtls_pk_debug(pk, items) != 0) {
327        debug_send_line(ssl, level, file, line,
328                        "invalid PK context\n");
329        return;
330    }
331
332    for (i = 0; i < MBEDTLS_PK_DEBUG_MAX_ITEMS; i++) {
333        if (items[i].type == MBEDTLS_PK_DEBUG_NONE) {
334            return;
335        }
336
337        mbedtls_snprintf(name, sizeof(name), "%s%s", text, items[i].name);
338        name[sizeof(name) - 1] = '\0';
339
340#if defined(MBEDTLS_RSA_C)
341        if (items[i].type == MBEDTLS_PK_DEBUG_MPI) {
342            mbedtls_debug_print_mpi(ssl, level, file, line, name, items[i].value);
343        } else
344#endif /* MBEDTLS_RSA_C */
345#if defined(MBEDTLS_ECP_LIGHT)
346        if (items[i].type == MBEDTLS_PK_DEBUG_ECP) {
347            mbedtls_debug_print_ecp(ssl, level, file, line, name, items[i].value);
348        } else
349#endif /* MBEDTLS_ECP_LIGHT */
350#if defined(MBEDTLS_PK_USE_PSA_EC_DATA)
351        if (items[i].type == MBEDTLS_PK_DEBUG_PSA_EC) {
352            mbedtls_debug_print_psa_ec(ssl, level, file, line, name, items[i].value);
353        } else
354#endif /* MBEDTLS_PK_USE_PSA_EC_DATA */
355        { debug_send_line(ssl, level, file, line,
356                          "should not happen\n"); }
357    }
358}
359
360static void debug_print_line_by_line(const mbedtls_ssl_context *ssl, int level,
361                                     const char *file, int line, const char *text)
362{
363    char str[DEBUG_BUF_SIZE];
364    const char *start, *cur;
365
366    start = text;
367    for (cur = text; *cur != '\0'; cur++) {
368        if (*cur == '\n') {
369            size_t len = (size_t) (cur - start) + 1;
370            if (len > DEBUG_BUF_SIZE - 1) {
371                len = DEBUG_BUF_SIZE - 1;
372            }
373
374            memcpy(str, start, len);
375            str[len] = '\0';
376
377            debug_send_line(ssl, level, file, line, str);
378
379            start = cur + 1;
380        }
381    }
382}
383
384void mbedtls_debug_print_crt(const mbedtls_ssl_context *ssl, int level,
385                             const char *file, int line,
386                             const char *text, const mbedtls_x509_crt *crt)
387{
388    char str[DEBUG_BUF_SIZE];
389    int i = 0;
390
391    if (NULL == ssl              ||
392        NULL == ssl->conf        ||
393        NULL == ssl->conf->f_dbg ||
394        NULL == crt              ||
395        level > debug_threshold) {
396        return;
397    }
398
399    while (crt != NULL) {
400        char buf[1024];
401
402        mbedtls_snprintf(str, sizeof(str), "%s #%d:\n", text, ++i);
403        debug_send_line(ssl, level, file, line, str);
404
405        mbedtls_x509_crt_info(buf, sizeof(buf) - 1, "", crt);
406        debug_print_line_by_line(ssl, level, file, line, buf);
407
408        debug_print_pk(ssl, level, file, line, "crt->", &crt->pk);
409
410        crt = crt->next;
411    }
412}
413#endif /* MBEDTLS_X509_CRT_PARSE_C && MBEDTLS_X509_REMOVE_INFO */
414
415#if defined(MBEDTLS_KEY_EXCHANGE_SOME_ECDH_OR_ECDHE_ANY_ENABLED) && \
416    defined(MBEDTLS_ECDH_C)
417static void mbedtls_debug_printf_ecdh_internal(const mbedtls_ssl_context *ssl,
418                                               int level, const char *file,
419                                               int line,
420                                               const mbedtls_ecdh_context *ecdh,
421                                               mbedtls_debug_ecdh_attr attr)
422{
423#if defined(MBEDTLS_ECDH_LEGACY_CONTEXT)
424    const mbedtls_ecdh_context *ctx = ecdh;
425#else
426    const mbedtls_ecdh_context_mbed *ctx = &ecdh->ctx.mbed_ecdh;
427#endif
428
429    switch (attr) {
430        case MBEDTLS_DEBUG_ECDH_Q:
431            mbedtls_debug_print_ecp(ssl, level, file, line, "ECDH: Q",
432                                    &ctx->Q);
433            break;
434        case MBEDTLS_DEBUG_ECDH_QP:
435            mbedtls_debug_print_ecp(ssl, level, file, line, "ECDH: Qp",
436                                    &ctx->Qp);
437            break;
438        case MBEDTLS_DEBUG_ECDH_Z:
439            mbedtls_debug_print_mpi(ssl, level, file, line, "ECDH: z",
440                                    &ctx->z);
441            break;
442        default:
443            break;
444    }
445}
446
447void mbedtls_debug_printf_ecdh(const mbedtls_ssl_context *ssl, int level,
448                               const char *file, int line,
449                               const mbedtls_ecdh_context *ecdh,
450                               mbedtls_debug_ecdh_attr attr)
451{
452#if defined(MBEDTLS_ECDH_LEGACY_CONTEXT)
453    mbedtls_debug_printf_ecdh_internal(ssl, level, file, line, ecdh, attr);
454#else
455    switch (ecdh->var) {
456        default:
457            mbedtls_debug_printf_ecdh_internal(ssl, level, file, line, ecdh,
458                                               attr);
459    }
460#endif
461}
462#endif /* MBEDTLS_KEY_EXCHANGE_SOME_ECDH_OR_ECDHE_ANY_ENABLED &&
463          MBEDTLS_ECDH_C */
464
465#endif /* MBEDTLS_DEBUG_C */
466