diff options
Diffstat (limited to 'src/lib/libssl/bytestring.h')
-rw-r--r-- | src/lib/libssl/bytestring.h | 346 |
1 files changed, 346 insertions, 0 deletions
diff --git a/src/lib/libssl/bytestring.h b/src/lib/libssl/bytestring.h new file mode 100644 index 0000000000..3c4e8eaaf3 --- /dev/null +++ b/src/lib/libssl/bytestring.h | |||
@@ -0,0 +1,346 @@ | |||
1 | /* $OpenBSD: bytestring.h,v 1.1 2015/02/06 09:36:16 doug Exp $ */ | ||
2 | /* | ||
3 | * Copyright (c) 2014, Google Inc. | ||
4 | * | ||
5 | * Permission to use, copy, modify, and/or distribute this software for any | ||
6 | * purpose with or without fee is hereby granted, provided that the above | ||
7 | * copyright notice and this permission notice appear in all copies. | ||
8 | * | ||
9 | * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES | ||
10 | * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF | ||
11 | * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY | ||
12 | * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES | ||
13 | * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION | ||
14 | * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN | ||
15 | * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ | ||
16 | |||
17 | #ifndef OPENSSL_HEADER_BYTESTRING_H | ||
18 | #define OPENSSL_HEADER_BYTESTRING_H | ||
19 | |||
20 | #if defined(__cplusplus) | ||
21 | extern "C" { | ||
22 | #endif | ||
23 | |||
24 | #include <sys/types.h> | ||
25 | #include <stdint.h> | ||
26 | |||
27 | #include <openssl/opensslconf.h> | ||
28 | |||
29 | /* Bytestrings are used for parsing and building TLS and ASN.1 messages. | ||
30 | * | ||
31 | * A "CBS" (CRYPTO ByteString) represents a string of bytes in memory and | ||
32 | * provides utility functions for safely parsing length-prefixed structures | ||
33 | * like TLS and ASN.1 from it. | ||
34 | * | ||
35 | * A "CBB" (CRYPTO ByteBuilder) is a memory buffer that grows as needed and | ||
36 | * provides utility functions for building length-prefixed messages. */ | ||
37 | |||
38 | |||
39 | /* CRYPTO ByteString */ | ||
40 | |||
41 | typedef struct cbs_st { | ||
42 | const uint8_t *data; | ||
43 | size_t len; | ||
44 | } CBS; | ||
45 | |||
46 | /* CBS_init sets |cbs| to point to |data|. It does not take ownership of | ||
47 | * |data|. */ | ||
48 | void CBS_init(CBS *cbs, const uint8_t *data, size_t len); | ||
49 | |||
50 | /* CBS_skip advances |cbs| by |len| bytes. It returns one on success and zero | ||
51 | * otherwise. */ | ||
52 | int CBS_skip(CBS *cbs, size_t len); | ||
53 | |||
54 | /* CBS_data returns a pointer to the contains of |cbs|. */ | ||
55 | const uint8_t *CBS_data(const CBS *cbs); | ||
56 | |||
57 | /* CBS_len returns the number of bytes remaining in |cbs|. */ | ||
58 | size_t CBS_len(const CBS *cbs); | ||
59 | |||
60 | /* CBS_stow copies the current contents of |cbs| into |*out_ptr| and | ||
61 | * |*out_len|. If |*out_ptr| is not NULL, the contents are freed with | ||
62 | * OPENSSL_free. It returns one on success and zero on allocation failure. On | ||
63 | * success, |*out_ptr| should be freed with OPENSSL_free. If |cbs| is empty, | ||
64 | * |*out_ptr| will be NULL. */ | ||
65 | int CBS_stow(const CBS *cbs, uint8_t **out_ptr, size_t *out_len); | ||
66 | |||
67 | /* CBS_strdup copies the current contents of |cbs| into |*out_ptr| as a | ||
68 | * NUL-terminated C string. If |*out_ptr| is not NULL, the contents are freed | ||
69 | * with OPENSSL_free. It returns one on success and zero on allocation | ||
70 | * failure. On success, |*out_ptr| should be freed with OPENSSL_free. | ||
71 | * | ||
72 | * NOTE: If |cbs| contains NUL bytes, the string will be truncated. Call | ||
73 | * |CBS_contains_zero_byte(cbs)| to check for NUL bytes. */ | ||
74 | int CBS_strdup(const CBS *cbs, char **out_ptr); | ||
75 | |||
76 | /* CBS_contains_zero_byte returns one if the current contents of |cbs| contains | ||
77 | * a NUL byte and zero otherwise. */ | ||
78 | int CBS_contains_zero_byte(const CBS *cbs); | ||
79 | |||
80 | /* CBS_mem_equal compares the current contents of |cbs| with the |len| bytes | ||
81 | * starting at |data|. If they're equal, it returns one, otherwise zero. If the | ||
82 | * lengths match, it uses a constant-time comparison. */ | ||
83 | int CBS_mem_equal(const CBS *cbs, const uint8_t *data, | ||
84 | size_t len); | ||
85 | |||
86 | /* CBS_get_u8 sets |*out| to the next uint8_t from |cbs| and advances |cbs|. It | ||
87 | * returns one on success and zero on error. */ | ||
88 | int CBS_get_u8(CBS *cbs, uint8_t *out); | ||
89 | |||
90 | /* CBS_get_u16 sets |*out| to the next, big-endian uint16_t from |cbs| and | ||
91 | * advances |cbs|. It returns one on success and zero on error. */ | ||
92 | int CBS_get_u16(CBS *cbs, uint16_t *out); | ||
93 | |||
94 | /* CBS_get_u24 sets |*out| to the next, big-endian 24-bit value from |cbs| and | ||
95 | * advances |cbs|. It returns one on success and zero on error. */ | ||
96 | int CBS_get_u24(CBS *cbs, uint32_t *out); | ||
97 | |||
98 | /* CBS_get_u32 sets |*out| to the next, big-endian uint32_t value from |cbs| | ||
99 | * and advances |cbs|. It returns one on success and zero on error. */ | ||
100 | int CBS_get_u32(CBS *cbs, uint32_t *out); | ||
101 | |||
102 | /* CBS_get_bytes sets |*out| to the next |len| bytes from |cbs| and advances | ||
103 | * |cbs|. It returns one on success and zero on error. */ | ||
104 | int CBS_get_bytes(CBS *cbs, CBS *out, size_t len); | ||
105 | |||
106 | /* CBS_get_u8_length_prefixed sets |*out| to the contents of an 8-bit, | ||
107 | * length-prefixed value from |cbs| and advances |cbs| over it. It returns one | ||
108 | * on success and zero on error. */ | ||
109 | int CBS_get_u8_length_prefixed(CBS *cbs, CBS *out); | ||
110 | |||
111 | /* CBS_get_u16_length_prefixed sets |*out| to the contents of a 16-bit, | ||
112 | * big-endian, length-prefixed value from |cbs| and advances |cbs| over it. It | ||
113 | * returns one on success and zero on error. */ | ||
114 | int CBS_get_u16_length_prefixed(CBS *cbs, CBS *out); | ||
115 | |||
116 | /* CBS_get_u24_length_prefixed sets |*out| to the contents of a 24-bit, | ||
117 | * big-endian, length-prefixed value from |cbs| and advances |cbs| over it. It | ||
118 | * returns one on success and zero on error. */ | ||
119 | int CBS_get_u24_length_prefixed(CBS *cbs, CBS *out); | ||
120 | |||
121 | |||
122 | /* Parsing ASN.1 */ | ||
123 | |||
124 | #define CBS_ASN1_BOOLEAN 0x1 | ||
125 | #define CBS_ASN1_INTEGER 0x2 | ||
126 | #define CBS_ASN1_BITSTRING 0x3 | ||
127 | #define CBS_ASN1_OCTETSTRING 0x4 | ||
128 | #define CBS_ASN1_OBJECT 0x6 | ||
129 | #define CBS_ASN1_ENUMERATED 0xa | ||
130 | #define CBS_ASN1_SEQUENCE (0x10 | CBS_ASN1_CONSTRUCTED) | ||
131 | #define CBS_ASN1_SET (0x11 | CBS_ASN1_CONSTRUCTED) | ||
132 | |||
133 | #define CBS_ASN1_CONSTRUCTED 0x20 | ||
134 | #define CBS_ASN1_CONTEXT_SPECIFIC 0x80 | ||
135 | |||
136 | /* CBS_get_asn1 sets |*out| to the contents of DER-encoded, ASN.1 element (not | ||
137 | * including tag and length bytes) and advances |cbs| over it. The ASN.1 | ||
138 | * element must match |tag_value|. It returns one on success and zero | ||
139 | * on error. | ||
140 | * | ||
141 | * Tag numbers greater than 31 are not supported. */ | ||
142 | int CBS_get_asn1(CBS *cbs, CBS *out, unsigned tag_value); | ||
143 | |||
144 | /* CBS_get_asn1_element acts like |CBS_get_asn1| but |out| will include the | ||
145 | * ASN.1 header bytes too. */ | ||
146 | int CBS_get_asn1_element(CBS *cbs, CBS *out, unsigned tag_value); | ||
147 | |||
148 | /* CBS_peek_asn1_tag looks ahead at the next ASN.1 tag and returns one | ||
149 | * if the next ASN.1 element on |cbs| would have tag |tag_value|. If | ||
150 | * |cbs| is empty or the tag does not match, it returns zero. Note: if | ||
151 | * it returns one, CBS_get_asn1 may still fail if the rest of the | ||
152 | * element is malformed. */ | ||
153 | int CBS_peek_asn1_tag(const CBS *cbs, unsigned tag_value); | ||
154 | |||
155 | /* CBS_get_any_asn1_element sets |*out| to contain the next ASN.1 element from | ||
156 | * |*cbs| (including header bytes) and advances |*cbs|. It sets |*out_tag| to | ||
157 | * the tag number and |*out_header_len| to the length of the ASN.1 header. If | ||
158 | * the element has indefinite length then |*out| will only contain the | ||
159 | * header. Each of |out|, |out_tag|, and |out_header_len| may be NULL to ignore | ||
160 | * the value. | ||
161 | * | ||
162 | * Tag numbers greater than 31 are not supported. */ | ||
163 | int CBS_get_any_asn1_element(CBS *cbs, CBS *out, | ||
164 | unsigned *out_tag, | ||
165 | size_t *out_header_len); | ||
166 | |||
167 | /* CBS_get_asn1_uint64 gets an ASN.1 INTEGER from |cbs| using |CBS_get_asn1| | ||
168 | * and sets |*out| to its value. It returns one on success and zero on error, | ||
169 | * where error includes the integer being negative, or too large to represent | ||
170 | * in 64 bits. */ | ||
171 | int CBS_get_asn1_uint64(CBS *cbs, uint64_t *out); | ||
172 | |||
173 | /* CBS_get_optional_asn1 gets an optional explicitly-tagged element | ||
174 | * from |cbs| tagged with |tag| and sets |*out| to its contents. If | ||
175 | * present, it sets |*out_present| to one, otherwise zero. It returns | ||
176 | * one on success, whether or not the element was present, and zero on | ||
177 | * decode failure. */ | ||
178 | int CBS_get_optional_asn1(CBS *cbs, CBS *out, int *out_present, | ||
179 | unsigned tag); | ||
180 | |||
181 | /* CBS_get_optional_asn1_octet_string gets an optional | ||
182 | * explicitly-tagged OCTET STRING from |cbs|. If present, it sets | ||
183 | * |*out| to the string and |*out_present| to one. Otherwise, it sets | ||
184 | * |*out| to empty and |*out_present| to zero. |out_present| may be | ||
185 | * NULL. It returns one on success, whether or not the element was | ||
186 | * present, and zero on decode failure. */ | ||
187 | int CBS_get_optional_asn1_octet_string(CBS *cbs, CBS *out, | ||
188 | int *out_present, | ||
189 | unsigned tag); | ||
190 | |||
191 | /* CBS_get_optional_asn1_uint64 gets an optional explicitly-tagged | ||
192 | * INTEGER from |cbs|. If present, it sets |*out| to the | ||
193 | * value. Otherwise, it sets |*out| to |default_value|. It returns one | ||
194 | * on success, whether or not the element was present, and zero on | ||
195 | * decode failure. */ | ||
196 | int CBS_get_optional_asn1_uint64(CBS *cbs, uint64_t *out, | ||
197 | unsigned tag, | ||
198 | uint64_t default_value); | ||
199 | |||
200 | /* CBS_get_optional_asn1_bool gets an optional, explicitly-tagged BOOLEAN from | ||
201 | * |cbs|. If present, it sets |*out| to either zero or one, based on the | ||
202 | * boolean. Otherwise, it sets |*out| to |default_value|. It returns one on | ||
203 | * success, whether or not the element was present, and zero on decode | ||
204 | * failure. */ | ||
205 | int CBS_get_optional_asn1_bool(CBS *cbs, int *out, unsigned tag, | ||
206 | int default_value); | ||
207 | |||
208 | |||
209 | /* CRYPTO ByteBuilder. | ||
210 | * | ||
211 | * |CBB| objects allow one to build length-prefixed serialisations. A |CBB| | ||
212 | * object is associated with a buffer and new buffers are created with | ||
213 | * |CBB_init|. Several |CBB| objects can point at the same buffer when a | ||
214 | * length-prefix is pending, however only a single |CBB| can be 'current' at | ||
215 | * any one time. For example, if one calls |CBB_add_u8_length_prefixed| then | ||
216 | * the new |CBB| points at the same buffer as the original. But if the original | ||
217 | * |CBB| is used then the length prefix is written out and the new |CBB| must | ||
218 | * not be used again. | ||
219 | * | ||
220 | * If one needs to force a length prefix to be written out because a |CBB| is | ||
221 | * going out of scope, use |CBB_flush|. */ | ||
222 | |||
223 | struct cbb_buffer_st { | ||
224 | uint8_t *buf; | ||
225 | size_t len; /* The number of valid bytes. */ | ||
226 | size_t cap; /* The size of buf. */ | ||
227 | char can_resize; /* One iff |buf| is owned by this object. If not then |buf| | ||
228 | cannot be resized. */ | ||
229 | }; | ||
230 | |||
231 | typedef struct cbb_st { | ||
232 | struct cbb_buffer_st *base; | ||
233 | /* offset is the offset from the start of |base->buf| to the position of any | ||
234 | * pending length-prefix. */ | ||
235 | size_t offset; | ||
236 | /* child points to a child CBB if a length-prefix is pending. */ | ||
237 | struct cbb_st *child; | ||
238 | /* pending_len_len contains the number of bytes in a pending length-prefix, | ||
239 | * or zero if no length-prefix is pending. */ | ||
240 | uint8_t pending_len_len; | ||
241 | char pending_is_asn1; | ||
242 | /* is_top_level is true iff this is a top-level |CBB| (as opposed to a child | ||
243 | * |CBB|). Top-level objects are valid arguments for |CBB_finish|. */ | ||
244 | char is_top_level; | ||
245 | } CBB; | ||
246 | |||
247 | /* CBB_init initialises |cbb| with |initial_capacity|. Since a |CBB| grows as | ||
248 | * needed, the |initial_capacity| is just a hint. It returns one on success or | ||
249 | * zero on error. */ | ||
250 | int CBB_init(CBB *cbb, size_t initial_capacity); | ||
251 | |||
252 | /* CBB_init_fixed initialises |cbb| to write to |len| bytes at |buf|. Since | ||
253 | * |buf| cannot grow, trying to write more than |len| bytes will cause CBB | ||
254 | * functions to fail. It returns one on success or zero on error. */ | ||
255 | int CBB_init_fixed(CBB *cbb, uint8_t *buf, size_t len); | ||
256 | |||
257 | /* CBB_cleanup frees all resources owned by |cbb| and other |CBB| objects | ||
258 | * writing to the same buffer. This should be used in an error case where a | ||
259 | * serialisation is abandoned. */ | ||
260 | void CBB_cleanup(CBB *cbb); | ||
261 | |||
262 | /* CBB_finish completes any pending length prefix and sets |*out_data| to a | ||
263 | * malloced buffer and |*out_len| to the length of that buffer. The caller | ||
264 | * takes ownership of the buffer and, unless the buffer was fixed with | ||
265 | * |CBB_init_fixed|, must call |OPENSSL_free| when done. | ||
266 | * | ||
267 | * It can only be called on a "top level" |CBB|, i.e. one initialised with | ||
268 | * |CBB_init| or |CBB_init_fixed|. It returns one on success and zero on | ||
269 | * error. */ | ||
270 | int CBB_finish(CBB *cbb, uint8_t **out_data, size_t *out_len); | ||
271 | |||
272 | /* CBB_flush causes any pending length prefixes to be written out and any child | ||
273 | * |CBB| objects of |cbb| to be invalidated. It returns one on success or zero | ||
274 | * on error. */ | ||
275 | int CBB_flush(CBB *cbb); | ||
276 | |||
277 | /* CBB_add_u8_length_prefixed sets |*out_contents| to a new child of |cbb|. The | ||
278 | * data written to |*out_contents| will be prefixed in |cbb| with an 8-bit | ||
279 | * length. It returns one on success or zero on error. */ | ||
280 | int CBB_add_u8_length_prefixed(CBB *cbb, CBB *out_contents); | ||
281 | |||
282 | /* CBB_add_u16_length_prefixed sets |*out_contents| to a new child of |cbb|. | ||
283 | * The data written to |*out_contents| will be prefixed in |cbb| with a 16-bit, | ||
284 | * big-endian length. It returns one on success or zero on error. */ | ||
285 | int CBB_add_u16_length_prefixed(CBB *cbb, CBB *out_contents); | ||
286 | |||
287 | /* CBB_add_u24_length_prefixed sets |*out_contents| to a new child of |cbb|. | ||
288 | * The data written to |*out_contents| will be prefixed in |cbb| with a 24-bit, | ||
289 | * big-endian length. It returns one on success or zero on error. */ | ||
290 | int CBB_add_u24_length_prefixed(CBB *cbb, CBB *out_contents); | ||
291 | |||
292 | /* CBB_add_asn sets |*out_contents| to a |CBB| into which the contents of an | ||
293 | * ASN.1 object can be written. The |tag| argument will be used as the tag for | ||
294 | * the object. It returns one on success or zero on error. */ | ||
295 | int CBB_add_asn1(CBB *cbb, CBB *out_contents, uint8_t tag); | ||
296 | |||
297 | /* CBB_add_bytes appends |len| bytes from |data| to |cbb|. It returns one on | ||
298 | * success and zero otherwise. */ | ||
299 | int CBB_add_bytes(CBB *cbb, const uint8_t *data, size_t len); | ||
300 | |||
301 | /* CBB_add_space appends |len| bytes to |cbb| and sets |*out_data| to point to | ||
302 | * the beginning of that space. The caller must then write |len| bytes of | ||
303 | * actual contents to |*out_data|. It returns one on success and zero | ||
304 | * otherwise. */ | ||
305 | int CBB_add_space(CBB *cbb, uint8_t **out_data, size_t len); | ||
306 | |||
307 | /* CBB_add_u8 appends an 8-bit number from |value| to |cbb|. It returns one on | ||
308 | * success and zero otherwise. */ | ||
309 | int CBB_add_u8(CBB *cbb, uint8_t value); | ||
310 | |||
311 | /* CBB_add_u8 appends a 16-bit, big-endian number from |value| to |cbb|. It | ||
312 | * returns one on success and zero otherwise. */ | ||
313 | int CBB_add_u16(CBB *cbb, uint16_t value); | ||
314 | |||
315 | /* CBB_add_u24 appends a 24-bit, big-endian number from |value| to |cbb|. It | ||
316 | * returns one on success and zero otherwise. */ | ||
317 | int CBB_add_u24(CBB *cbb, uint32_t value); | ||
318 | |||
319 | /* CBB_add_asn1_uint64 writes an ASN.1 INTEGER into |cbb| using |CBB_add_asn1| | ||
320 | * and writes |value| in its contents. It returns one on success and zero on | ||
321 | * error. */ | ||
322 | int CBB_add_asn1_uint64(CBB *cbb, uint64_t value); | ||
323 | |||
324 | #ifdef LIBRESSL_INTERNAL | ||
325 | /* CBS_asn1_ber_to_der reads an ASN.1 structure from |in|. If it finds | ||
326 | * indefinite-length elements then it attempts to convert the BER data to DER | ||
327 | * and sets |*out| and |*out_length| to describe a malloced buffer containing | ||
328 | * the DER data. Additionally, |*in| will be advanced over the ASN.1 data. | ||
329 | * | ||
330 | * If it doesn't find any indefinite-length elements then it sets |*out| to | ||
331 | * NULL and |*in| is unmodified. | ||
332 | * | ||
333 | * A sufficiently complex ASN.1 structure will break this function because it's | ||
334 | * not possible to generically convert BER to DER without knowledge of the | ||
335 | * structure itself. However, this sufficies to handle the PKCS#7 and #12 output | ||
336 | * from NSS. | ||
337 | * | ||
338 | * It returns one on success and zero otherwise. */ | ||
339 | int CBS_asn1_ber_to_der(CBS *in, uint8_t **out, size_t *out_len); | ||
340 | #endif /* LIBRESSL_INTERNAL */ | ||
341 | |||
342 | #if defined(__cplusplus) | ||
343 | } /* extern C */ | ||
344 | #endif | ||
345 | |||
346 | #endif /* OPENSSL_HEADER_BYTESTRING_H */ | ||