1/* Copyright (c) 2014, Google Inc.
2 *
3 * Permission to use, copy, modify, and/or distribute this software for any
4 * purpose with or without fee is hereby granted, provided that the above
5 * copyright notice and this permission notice appear in all copies.
6 *
7 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
8 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
9 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
10 * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
11 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
12 * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
13 * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */
14
15#ifndef OPENSSL_HEADER_BYTESTRING_H
16#define OPENSSL_HEADER_BYTESTRING_H
17
18#include <openssl/base.h>
19
20#include <openssl/span.h>
21
22#if defined(__cplusplus)
23extern "C" {
24#endif
25
26
27// Bytestrings are used for parsing and building TLS and ASN.1 messages.
28//
29// A "CBS" (CRYPTO ByteString) represents a string of bytes in memory and
30// provides utility functions for safely parsing length-prefixed structures
31// like TLS and ASN.1 from it.
32//
33// A "CBB" (CRYPTO ByteBuilder) is a memory buffer that grows as needed and
34// provides utility functions for building length-prefixed messages.
35
36
37// CRYPTO ByteString
38
39struct cbs_st {
40 const uint8_t *data;
41 size_t len;
42
43#if !defined(BORINGSSL_NO_CXX)
44 // Allow implicit conversions to and from bssl::Span<const uint8_t>.
45 cbs_st(bssl::Span<const uint8_t> span)
46 : data(span.data()), len(span.size()) {}
47 operator bssl::Span<const uint8_t>() const {
48 return bssl::MakeConstSpan(data, len);
49 }
50
51 // Defining any constructors requires we explicitly default the others.
52 cbs_st() = default;
53 cbs_st(const cbs_st &) = default;
54#endif
55};
56
57// CBS_init sets |cbs| to point to |data|. It does not take ownership of
58// |data|.
59OPENSSL_EXPORT void CBS_init(CBS *cbs, const uint8_t *data, size_t len);
60
61// CBS_skip advances |cbs| by |len| bytes. It returns one on success and zero
62// otherwise.
63OPENSSL_EXPORT int CBS_skip(CBS *cbs, size_t len);
64
65// CBS_data returns a pointer to the contents of |cbs|.
66OPENSSL_EXPORT const uint8_t *CBS_data(const CBS *cbs);
67
68// CBS_len returns the number of bytes remaining in |cbs|.
69OPENSSL_EXPORT size_t CBS_len(const CBS *cbs);
70
71// CBS_stow copies the current contents of |cbs| into |*out_ptr| and
72// |*out_len|. If |*out_ptr| is not NULL, the contents are freed with
73// OPENSSL_free. It returns one on success and zero on allocation failure. On
74// success, |*out_ptr| should be freed with OPENSSL_free. If |cbs| is empty,
75// |*out_ptr| will be NULL.
76OPENSSL_EXPORT int CBS_stow(const CBS *cbs, uint8_t **out_ptr, size_t *out_len);
77
78// CBS_strdup copies the current contents of |cbs| into |*out_ptr| as a
79// NUL-terminated C string. If |*out_ptr| is not NULL, the contents are freed
80// with OPENSSL_free. It returns one on success and zero on allocation
81// failure. On success, |*out_ptr| should be freed with OPENSSL_free.
82//
83// NOTE: If |cbs| contains NUL bytes, the string will be truncated. Call
84// |CBS_contains_zero_byte(cbs)| to check for NUL bytes.
85OPENSSL_EXPORT int CBS_strdup(const CBS *cbs, char **out_ptr);
86
87// CBS_contains_zero_byte returns one if the current contents of |cbs| contains
88// a NUL byte and zero otherwise.
89OPENSSL_EXPORT int CBS_contains_zero_byte(const CBS *cbs);
90
91// CBS_mem_equal compares the current contents of |cbs| with the |len| bytes
92// starting at |data|. If they're equal, it returns one, otherwise zero. If the
93// lengths match, it uses a constant-time comparison.
94OPENSSL_EXPORT int CBS_mem_equal(const CBS *cbs, const uint8_t *data,
95 size_t len);
96
97// CBS_get_u8 sets |*out| to the next uint8_t from |cbs| and advances |cbs|. It
98// returns one on success and zero on error.
99OPENSSL_EXPORT int CBS_get_u8(CBS *cbs, uint8_t *out);
100
101// CBS_get_u16 sets |*out| to the next, big-endian uint16_t from |cbs| and
102// advances |cbs|. It returns one on success and zero on error.
103OPENSSL_EXPORT int CBS_get_u16(CBS *cbs, uint16_t *out);
104
105// CBS_get_u24 sets |*out| to the next, big-endian 24-bit value from |cbs| and
106// advances |cbs|. It returns one on success and zero on error.
107OPENSSL_EXPORT int CBS_get_u24(CBS *cbs, uint32_t *out);
108
109// CBS_get_u32 sets |*out| to the next, big-endian uint32_t value from |cbs|
110// and advances |cbs|. It returns one on success and zero on error.
111OPENSSL_EXPORT int CBS_get_u32(CBS *cbs, uint32_t *out);
112
113// CBS_get_u64 sets |*out| to the next, big-endian uint64_t value from |cbs|
114// and advances |cbs|. It returns one on success and zero on error.
115OPENSSL_EXPORT int CBS_get_u64(CBS *cbs, uint64_t *out);
116
117// CBS_get_last_u8 sets |*out| to the last uint8_t from |cbs| and shortens
118// |cbs|. It returns one on success and zero on error.
119OPENSSL_EXPORT int CBS_get_last_u8(CBS *cbs, uint8_t *out);
120
121// CBS_get_bytes sets |*out| to the next |len| bytes from |cbs| and advances
122// |cbs|. It returns one on success and zero on error.
123OPENSSL_EXPORT int CBS_get_bytes(CBS *cbs, CBS *out, size_t len);
124
125// CBS_copy_bytes copies the next |len| bytes from |cbs| to |out| and advances
126// |cbs|. It returns one on success and zero on error.
127OPENSSL_EXPORT int CBS_copy_bytes(CBS *cbs, uint8_t *out, size_t len);
128
129// CBS_get_u8_length_prefixed sets |*out| to the contents of an 8-bit,
130// length-prefixed value from |cbs| and advances |cbs| over it. It returns one
131// on success and zero on error.
132OPENSSL_EXPORT int CBS_get_u8_length_prefixed(CBS *cbs, CBS *out);
133
134// CBS_get_u16_length_prefixed sets |*out| to the contents of a 16-bit,
135// big-endian, length-prefixed value from |cbs| and advances |cbs| over it. It
136// returns one on success and zero on error.
137OPENSSL_EXPORT int CBS_get_u16_length_prefixed(CBS *cbs, CBS *out);
138
139// CBS_get_u24_length_prefixed sets |*out| to the contents of a 24-bit,
140// big-endian, length-prefixed value from |cbs| and advances |cbs| over it. It
141// returns one on success and zero on error.
142OPENSSL_EXPORT int CBS_get_u24_length_prefixed(CBS *cbs, CBS *out);
143
144
145// Parsing ASN.1
146//
147// |CBS| may be used to parse DER structures. Rather than using a schema
148// compiler, the following functions act on tag-length-value elements in the
149// serialization itself. Thus the caller is responsible for looping over a
150// SEQUENCE, branching on CHOICEs or OPTIONAL fields, checking for trailing
151// data, and handling explict vs. implicit tagging.
152//
153// Tags are represented as |unsigned| values in memory. The upper few bits store
154// the class and constructed bit, and the remaining bits store the tag
155// number. Note this differs from the DER serialization, to support tag numbers
156// beyond 31. Consumers must use the constants defined below to decompose or
157// assemble tags.
158//
159// This library treats an element's constructed bit as part of its tag. In DER,
160// the constructed bit is computable from the type. The constants for universal
161// types have the bit set. Callers must set it correctly for tagged types.
162// Explicitly-tagged types are always constructed, and implicitly-tagged types
163// inherit the underlying type's bit.
164
165// CBS_ASN1_TAG_SHIFT is how much the in-memory representation shifts the class
166// and constructed bits from the DER serialization.
167#define CBS_ASN1_TAG_SHIFT 24
168
169// CBS_ASN1_CONSTRUCTED may be ORed into a tag to set the constructed bit.
170#define CBS_ASN1_CONSTRUCTED (0x20u << CBS_ASN1_TAG_SHIFT)
171
172// The following values specify the tag class and may be ORed into a tag number
173// to produce the final tag. If none is used, the tag will be UNIVERSAL.
174#define CBS_ASN1_UNIVERSAL (0u << CBS_ASN1_TAG_SHIFT)
175#define CBS_ASN1_APPLICATION (0x40u << CBS_ASN1_TAG_SHIFT)
176#define CBS_ASN1_CONTEXT_SPECIFIC (0x80u << CBS_ASN1_TAG_SHIFT)
177#define CBS_ASN1_PRIVATE (0xc0u << CBS_ASN1_TAG_SHIFT)
178
179// CBS_ASN1_CLASS_MASK may be ANDed with a tag to query its class. This will
180// give one of the four values above.
181#define CBS_ASN1_CLASS_MASK (0xc0u << CBS_ASN1_TAG_SHIFT)
182
183// CBS_ASN1_TAG_NUMBER_MASK may be ANDed with a tag to query its number.
184#define CBS_ASN1_TAG_NUMBER_MASK ((1u << (5 + CBS_ASN1_TAG_SHIFT)) - 1)
185
186// The following values are constants for UNIVERSAL tags. Note these constants
187// include the constructed bit.
188#define CBS_ASN1_BOOLEAN 0x1u
189#define CBS_ASN1_INTEGER 0x2u
190#define CBS_ASN1_BITSTRING 0x3u
191#define CBS_ASN1_OCTETSTRING 0x4u
192#define CBS_ASN1_NULL 0x5u
193#define CBS_ASN1_OBJECT 0x6u
194#define CBS_ASN1_ENUMERATED 0xau
195#define CBS_ASN1_UTF8STRING 0xcu
196#define CBS_ASN1_SEQUENCE (0x10u | CBS_ASN1_CONSTRUCTED)
197#define CBS_ASN1_SET (0x11u | CBS_ASN1_CONSTRUCTED)
198#define CBS_ASN1_NUMERICSTRING 0x12u
199#define CBS_ASN1_PRINTABLESTRING 0x13u
200#define CBS_ASN1_T61STRING 0x14u
201#define CBS_ASN1_VIDEOTEXSTRING 0x15u
202#define CBS_ASN1_IA5STRING 0x16u
203#define CBS_ASN1_UTCTIME 0x17u
204#define CBS_ASN1_GENERALIZEDTIME 0x18u
205#define CBS_ASN1_GRAPHICSTRING 0x19u
206#define CBS_ASN1_VISIBLESTRING 0x1au
207#define CBS_ASN1_GENERALSTRING 0x1bu
208#define CBS_ASN1_UNIVERSALSTRING 0x1cu
209#define CBS_ASN1_BMPSTRING 0x1eu
210
211// CBS_get_asn1 sets |*out| to the contents of DER-encoded, ASN.1 element (not
212// including tag and length bytes) and advances |cbs| over it. The ASN.1
213// element must match |tag_value|. It returns one on success and zero
214// on error.
215OPENSSL_EXPORT int CBS_get_asn1(CBS *cbs, CBS *out, unsigned tag_value);
216
217// CBS_get_asn1_element acts like |CBS_get_asn1| but |out| will include the
218// ASN.1 header bytes too.
219OPENSSL_EXPORT int CBS_get_asn1_element(CBS *cbs, CBS *out, unsigned tag_value);
220
221// CBS_peek_asn1_tag looks ahead at the next ASN.1 tag and returns one
222// if the next ASN.1 element on |cbs| would have tag |tag_value|. If
223// |cbs| is empty or the tag does not match, it returns zero. Note: if
224// it returns one, CBS_get_asn1 may still fail if the rest of the
225// element is malformed.
226OPENSSL_EXPORT int CBS_peek_asn1_tag(const CBS *cbs, unsigned tag_value);
227
228// CBS_get_any_asn1 sets |*out| to contain the next ASN.1 element from |*cbs|
229// (not including tag and length bytes), sets |*out_tag| to the tag number, and
230// advances |*cbs|. It returns one on success and zero on error. Either of |out|
231// and |out_tag| may be NULL to ignore the value.
232OPENSSL_EXPORT int CBS_get_any_asn1(CBS *cbs, CBS *out, unsigned *out_tag);
233
234// CBS_get_any_asn1_element sets |*out| to contain the next ASN.1 element from
235// |*cbs| (including header bytes) and advances |*cbs|. It sets |*out_tag| to
236// the tag number and |*out_header_len| to the length of the ASN.1 header. Each
237// of |out|, |out_tag|, and |out_header_len| may be NULL to ignore the value.
238OPENSSL_EXPORT int CBS_get_any_asn1_element(CBS *cbs, CBS *out,
239 unsigned *out_tag,
240 size_t *out_header_len);
241
242// CBS_get_any_ber_asn1_element acts the same as |CBS_get_any_asn1_element| but
243// also allows indefinite-length elements to be returned. In that case,
244// |*out_header_len| and |CBS_len(out)| will both be two as only the header is
245// returned, otherwise it behaves the same as the previous function.
246OPENSSL_EXPORT int CBS_get_any_ber_asn1_element(CBS *cbs, CBS *out,
247 unsigned *out_tag,
248 size_t *out_header_len);
249
250// CBS_get_asn1_uint64 gets an ASN.1 INTEGER from |cbs| using |CBS_get_asn1|
251// and sets |*out| to its value. It returns one on success and zero on error,
252// where error includes the integer being negative, or too large to represent
253// in 64 bits.
254OPENSSL_EXPORT int CBS_get_asn1_uint64(CBS *cbs, uint64_t *out);
255
256// CBS_get_asn1_bool gets an ASN.1 BOOLEAN from |cbs| and sets |*out| to zero
257// or one based on its value. It returns one on success or zero on error.
258OPENSSL_EXPORT int CBS_get_asn1_bool(CBS *cbs, int *out);
259
260// CBS_get_optional_asn1 gets an optional explicitly-tagged element from |cbs|
261// tagged with |tag| and sets |*out| to its contents, or ignores it if |out| is
262// NULL. If present and if |out_present| is not NULL, it sets |*out_present| to
263// one, otherwise zero. It returns one on success, whether or not the element
264// was present, and zero on decode failure.
265OPENSSL_EXPORT int CBS_get_optional_asn1(CBS *cbs, CBS *out, int *out_present,
266 unsigned tag);
267
268// CBS_get_optional_asn1_octet_string gets an optional
269// explicitly-tagged OCTET STRING from |cbs|. If present, it sets
270// |*out| to the string and |*out_present| to one. Otherwise, it sets
271// |*out| to empty and |*out_present| to zero. |out_present| may be
272// NULL. It returns one on success, whether or not the element was
273// present, and zero on decode failure.
274OPENSSL_EXPORT int CBS_get_optional_asn1_octet_string(CBS *cbs, CBS *out,
275 int *out_present,
276 unsigned tag);
277
278// CBS_get_optional_asn1_uint64 gets an optional explicitly-tagged
279// INTEGER from |cbs|. If present, it sets |*out| to the
280// value. Otherwise, it sets |*out| to |default_value|. It returns one
281// on success, whether or not the element was present, and zero on
282// decode failure.
283OPENSSL_EXPORT int CBS_get_optional_asn1_uint64(CBS *cbs, uint64_t *out,
284 unsigned tag,
285 uint64_t default_value);
286
287// CBS_get_optional_asn1_bool gets an optional, explicitly-tagged BOOLEAN from
288// |cbs|. If present, it sets |*out| to either zero or one, based on the
289// boolean. Otherwise, it sets |*out| to |default_value|. It returns one on
290// success, whether or not the element was present, and zero on decode
291// failure.
292OPENSSL_EXPORT int CBS_get_optional_asn1_bool(CBS *cbs, int *out, unsigned tag,
293 int default_value);
294
295// CBS_is_valid_asn1_bitstring returns one if |cbs| is a valid ASN.1 BIT STRING
296// and zero otherwise.
297OPENSSL_EXPORT int CBS_is_valid_asn1_bitstring(const CBS *cbs);
298
299// CBS_asn1_bitstring_has_bit returns one if |cbs| is a valid ASN.1 BIT STRING
300// and the specified bit is present and set. Otherwise, it returns zero. |bit|
301// is indexed starting from zero.
302OPENSSL_EXPORT int CBS_asn1_bitstring_has_bit(const CBS *cbs, unsigned bit);
303
304// CBS_asn1_oid_to_text interprets |cbs| as DER-encoded ASN.1 OBJECT IDENTIFIER
305// contents (not including the element framing) and returns the ASCII
306// representation (e.g., "1.2.840.113554.4.1.72585") in a newly-allocated
307// string, or NULL on failure. The caller must release the result with
308// |OPENSSL_free|.
309OPENSSL_EXPORT char *CBS_asn1_oid_to_text(const CBS *cbs);
310
311
312// CRYPTO ByteBuilder.
313//
314// |CBB| objects allow one to build length-prefixed serialisations. A |CBB|
315// object is associated with a buffer and new buffers are created with
316// |CBB_init|. Several |CBB| objects can point at the same buffer when a
317// length-prefix is pending, however only a single |CBB| can be 'current' at
318// any one time. For example, if one calls |CBB_add_u8_length_prefixed| then
319// the new |CBB| points at the same buffer as the original. But if the original
320// |CBB| is used then the length prefix is written out and the new |CBB| must
321// not be used again.
322//
323// If one needs to force a length prefix to be written out because a |CBB| is
324// going out of scope, use |CBB_flush|. If an operation on a |CBB| fails, it is
325// in an undefined state and must not be used except to call |CBB_cleanup|.
326
327struct cbb_buffer_st {
328 uint8_t *buf;
329 size_t len; // The number of valid bytes.
330 size_t cap; // The size of buf.
331 char can_resize; /* One iff |buf| is owned by this object. If not then |buf|
332 cannot be resized. */
333 char error; /* One iff there was an error writing to this CBB. All future
334 operations will fail. */
335};
336
337struct cbb_st {
338 struct cbb_buffer_st *base;
339 // child points to a child CBB if a length-prefix is pending.
340 CBB *child;
341 // offset is the number of bytes from the start of |base->buf| to this |CBB|'s
342 // pending length prefix.
343 size_t offset;
344 // pending_len_len contains the number of bytes in this |CBB|'s pending
345 // length-prefix, or zero if no length-prefix is pending.
346 uint8_t pending_len_len;
347 char pending_is_asn1;
348 // is_child is true iff this is a child |CBB| (as opposed to a top-level
349 // |CBB|). Top-level objects are valid arguments for |CBB_finish|.
350 char is_child;
351};
352
353// CBB_zero sets an uninitialised |cbb| to the zero state. It must be
354// initialised with |CBB_init| or |CBB_init_fixed| before use, but it is safe to
355// call |CBB_cleanup| without a successful |CBB_init|. This may be used for more
356// uniform cleanup of a |CBB|.
357OPENSSL_EXPORT void CBB_zero(CBB *cbb);
358
359// CBB_init initialises |cbb| with |initial_capacity|. Since a |CBB| grows as
360// needed, the |initial_capacity| is just a hint. It returns one on success or
361// zero on allocation failure.
362OPENSSL_EXPORT int CBB_init(CBB *cbb, size_t initial_capacity);
363
364// CBB_init_fixed initialises |cbb| to write to |len| bytes at |buf|. Since
365// |buf| cannot grow, trying to write more than |len| bytes will cause CBB
366// functions to fail. It returns one on success or zero on error.
367OPENSSL_EXPORT int CBB_init_fixed(CBB *cbb, uint8_t *buf, size_t len);
368
369// CBB_cleanup frees all resources owned by |cbb| and other |CBB| objects
370// writing to the same buffer. This should be used in an error case where a
371// serialisation is abandoned.
372//
373// This function can only be called on a "top level" |CBB|, i.e. one initialised
374// with |CBB_init| or |CBB_init_fixed|, or a |CBB| set to the zero state with
375// |CBB_zero|.
376OPENSSL_EXPORT void CBB_cleanup(CBB *cbb);
377
378// CBB_finish completes any pending length prefix and sets |*out_data| to a
379// malloced buffer and |*out_len| to the length of that buffer. The caller
380// takes ownership of the buffer and, unless the buffer was fixed with
381// |CBB_init_fixed|, must call |OPENSSL_free| when done.
382//
383// It can only be called on a "top level" |CBB|, i.e. one initialised with
384// |CBB_init| or |CBB_init_fixed|. It returns one on success and zero on
385// error.
386OPENSSL_EXPORT int CBB_finish(CBB *cbb, uint8_t **out_data, size_t *out_len);
387
388// CBB_flush causes any pending length prefixes to be written out and any child
389// |CBB| objects of |cbb| to be invalidated. This allows |cbb| to continue to be
390// used after the children go out of scope, e.g. when local |CBB| objects are
391// added as children to a |CBB| that persists after a function returns. This
392// function returns one on success or zero on error.
393OPENSSL_EXPORT int CBB_flush(CBB *cbb);
394
395// CBB_data returns a pointer to the bytes written to |cbb|. It does not flush
396// |cbb|. The pointer is valid until the next operation to |cbb|.
397//
398// To avoid unfinalized length prefixes, it is a fatal error to call this on a
399// CBB with any active children.
400OPENSSL_EXPORT const uint8_t *CBB_data(const CBB *cbb);
401
402// CBB_len returns the number of bytes written to |cbb|. It does not flush
403// |cbb|.
404//
405// To avoid unfinalized length prefixes, it is a fatal error to call this on a
406// CBB with any active children.
407OPENSSL_EXPORT size_t CBB_len(const CBB *cbb);
408
409// CBB_add_u8_length_prefixed sets |*out_contents| to a new child of |cbb|. The
410// data written to |*out_contents| will be prefixed in |cbb| with an 8-bit
411// length. It returns one on success or zero on error.
412OPENSSL_EXPORT int CBB_add_u8_length_prefixed(CBB *cbb, CBB *out_contents);
413
414// CBB_add_u16_length_prefixed sets |*out_contents| to a new child of |cbb|.
415// The data written to |*out_contents| will be prefixed in |cbb| with a 16-bit,
416// big-endian length. It returns one on success or zero on error.
417OPENSSL_EXPORT int CBB_add_u16_length_prefixed(CBB *cbb, CBB *out_contents);
418
419// CBB_add_u24_length_prefixed sets |*out_contents| to a new child of |cbb|.
420// The data written to |*out_contents| will be prefixed in |cbb| with a 24-bit,
421// big-endian length. It returns one on success or zero on error.
422OPENSSL_EXPORT int CBB_add_u24_length_prefixed(CBB *cbb, CBB *out_contents);
423
424// CBB_add_asn1 sets |*out_contents| to a |CBB| into which the contents of an
425// ASN.1 object can be written. The |tag| argument will be used as the tag for
426// the object. It returns one on success or zero on error.
427OPENSSL_EXPORT int CBB_add_asn1(CBB *cbb, CBB *out_contents, unsigned tag);
428
429// CBB_add_bytes appends |len| bytes from |data| to |cbb|. It returns one on
430// success and zero otherwise.
431OPENSSL_EXPORT int CBB_add_bytes(CBB *cbb, const uint8_t *data, size_t len);
432
433// CBB_add_space appends |len| bytes to |cbb| and sets |*out_data| to point to
434// the beginning of that space. The caller must then write |len| bytes of
435// actual contents to |*out_data|. It returns one on success and zero
436// otherwise.
437OPENSSL_EXPORT int CBB_add_space(CBB *cbb, uint8_t **out_data, size_t len);
438
439// CBB_reserve ensures |cbb| has room for |len| additional bytes and sets
440// |*out_data| to point to the beginning of that space. It returns one on
441// success and zero otherwise. The caller may write up to |len| bytes to
442// |*out_data| and call |CBB_did_write| to complete the write. |*out_data| is
443// valid until the next operation on |cbb| or an ancestor |CBB|.
444OPENSSL_EXPORT int CBB_reserve(CBB *cbb, uint8_t **out_data, size_t len);
445
446// CBB_did_write advances |cbb| by |len| bytes, assuming the space has been
447// written to by the caller. It returns one on success and zero on error.
448OPENSSL_EXPORT int CBB_did_write(CBB *cbb, size_t len);
449
450// CBB_add_u8 appends an 8-bit number from |value| to |cbb|. It returns one on
451// success and zero otherwise.
452OPENSSL_EXPORT int CBB_add_u8(CBB *cbb, uint8_t value);
453
454// CBB_add_u16 appends a 16-bit, big-endian number from |value| to |cbb|. It
455// returns one on success and zero otherwise.
456OPENSSL_EXPORT int CBB_add_u16(CBB *cbb, uint16_t value);
457
458// CBB_add_u24 appends a 24-bit, big-endian number from |value| to |cbb|. It
459// returns one on success and zero otherwise.
460OPENSSL_EXPORT int CBB_add_u24(CBB *cbb, uint32_t value);
461
462// CBB_add_u32 appends a 32-bit, big-endian number from |value| to |cbb|. It
463// returns one on success and zero otherwise.
464OPENSSL_EXPORT int CBB_add_u32(CBB *cbb, uint32_t value);
465
466// CBB_add_u64 appends a 64-bit, big-endian number from |value| to |cbb|. It
467// returns one on success and zero otherwise.
468OPENSSL_EXPORT int CBB_add_u64(CBB *cbb, uint64_t value);
469
470// CBB_discard_child discards the current unflushed child of |cbb|. Neither the
471// child's contents nor the length prefix will be included in the output.
472OPENSSL_EXPORT void CBB_discard_child(CBB *cbb);
473
474// CBB_add_asn1_uint64 writes an ASN.1 INTEGER into |cbb| using |CBB_add_asn1|
475// and writes |value| in its contents. It returns one on success and zero on
476// error.
477OPENSSL_EXPORT int CBB_add_asn1_uint64(CBB *cbb, uint64_t value);
478
479// CBB_add_asn1_octet_string writes an ASN.1 OCTET STRING into |cbb| with the
480// given contents. It returns one on success and zero on error.
481OPENSSL_EXPORT int CBB_add_asn1_octet_string(CBB *cbb, const uint8_t *data,
482 size_t data_len);
483
484// CBB_add_asn1_bool writes an ASN.1 BOOLEAN into |cbb| which is true iff
485// |value| is non-zero. It returns one on success and zero on error.
486OPENSSL_EXPORT int CBB_add_asn1_bool(CBB *cbb, int value);
487
488// CBB_add_asn1_oid_from_text decodes |len| bytes from |text| as an ASCII OID
489// representation, e.g. "1.2.840.113554.4.1.72585", and writes the DER-encoded
490// contents to |cbb|. It returns one on success and zero on malloc failure or if
491// |text| was invalid. It does not include the OBJECT IDENTIFER framing, only
492// the element's contents.
493//
494// This function considers OID strings with components which do not fit in a
495// |uint64_t| to be invalid.
496OPENSSL_EXPORT int CBB_add_asn1_oid_from_text(CBB *cbb, const char *text,
497 size_t len);
498
499// CBB_flush_asn1_set_of calls |CBB_flush| on |cbb| and then reorders the
500// contents for a DER-encoded ASN.1 SET OF type. It returns one on success and
501// zero on failure. DER canonicalizes SET OF contents by sorting
502// lexicographically by encoding. Call this function when encoding a SET OF
503// type in an order that is not already known to be canonical.
504//
505// Note a SET type has a slightly different ordering than a SET OF.
506OPENSSL_EXPORT int CBB_flush_asn1_set_of(CBB *cbb);
507
508
509#if defined(__cplusplus)
510} // extern C
511
512
513#if !defined(BORINGSSL_NO_CXX)
514extern "C++" {
515
516BSSL_NAMESPACE_BEGIN
517
518using ScopedCBB = internal::StackAllocated<CBB, void, CBB_zero, CBB_cleanup>;
519
520BSSL_NAMESPACE_END
521
522} // extern C++
523#endif
524
525#endif
526
527#endif // OPENSSL_HEADER_BYTESTRING_H
528