1 /* $OpenBSD: sshbuf.h,v 1.11 2018/07/09 21:56:06 markus Exp $ */
3 * Copyright (c) 2011 Damien Miller
5 * Permission to use, copy, modify, and 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.
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
12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
21 #include <sys/types.h>
25 # include <openssl/bn.h>
26 # ifdef OPENSSL_HAS_ECC
27 # include <openssl/ec.h>
28 # endif /* OPENSSL_HAS_ECC */
29 #endif /* WITH_OPENSSL */
31 #define SSHBUF_SIZE_MAX 0x8000000 /* Hard maximum size */
32 #define SSHBUF_REFS_MAX 0x100000 /* Max child buffers */
33 #define SSHBUF_MAX_BIGNUM (16384 / 8) /* Max bignum *bytes* */
34 #define SSHBUF_MAX_ECPOINT ((528 * 2 / 8) + 1) /* Max EC point *bytes* */
37 * NB. do not depend on the internals of this. It will be made opaque
42 const u_char *cd; /* Const data */
43 size_t off; /* First available byte is buf->d + buf->off */
44 size_t size; /* Last byte is buf->d + buf->size - 1 */
45 size_t max_size; /* Maximum size of buffer */
46 size_t alloc; /* Total bytes allocated to buf->d */
47 int readonly; /* Refers to external, const data */
48 int dont_free; /* Kludge to support sshbuf_init */
49 u_int refcount; /* Tracks self and number of child buffers */
50 struct sshbuf *parent; /* If child, pointer to parent */
54 * Create a new sshbuf buffer.
55 * Returns pointer to buffer on success, or NULL on allocation failure.
57 struct sshbuf *sshbuf_new(void);
60 * Create a new, read-only sshbuf buffer from existing data.
61 * Returns pointer to buffer on success, or NULL on allocation failure.
63 struct sshbuf *sshbuf_from(const void *blob, size_t len);
66 * Create a new, read-only sshbuf buffer from the contents of an existing
67 * buffer. The contents of "buf" must not change in the lifetime of the
69 * Returns pointer to buffer on success, or NULL on allocation failure.
71 struct sshbuf *sshbuf_fromb(struct sshbuf *buf);
74 * Create a new, read-only sshbuf buffer from the contents of a string in
75 * an existing buffer (the string is consumed in the process).
76 * The contents of "buf" must not change in the lifetime of the resultant
78 * Returns pointer to buffer on success, or NULL on allocation failure.
80 int sshbuf_froms(struct sshbuf *buf, struct sshbuf **bufp);
85 void sshbuf_free(struct sshbuf *buf);
88 * Reset buf, clearing its contents. NB. max_size is preserved.
90 void sshbuf_reset(struct sshbuf *buf);
93 * Return the maximum size of buf
95 size_t sshbuf_max_size(const struct sshbuf *buf);
98 * Set the maximum size of buf
99 * Returns 0 on success, or a negative SSH_ERR_* error code on failure.
101 int sshbuf_set_max_size(struct sshbuf *buf, size_t max_size);
104 * Returns the length of data in buf
106 size_t sshbuf_len(const struct sshbuf *buf);
109 * Returns number of bytes left in buffer before hitting max_size.
111 size_t sshbuf_avail(const struct sshbuf *buf);
114 * Returns a read-only pointer to the start of the data in buf
116 const u_char *sshbuf_ptr(const struct sshbuf *buf);
119 * Returns a mutable pointer to the start of the data in buf, or
120 * NULL if the buffer is read-only.
122 u_char *sshbuf_mutable_ptr(const struct sshbuf *buf);
125 * Check whether a reservation of size len will succeed in buf
126 * Safer to use than direct comparisons again sshbuf_avail as it copes
127 * with unsigned overflows correctly.
128 * Returns 0 on success, or a negative SSH_ERR_* error code on failure.
130 int sshbuf_check_reserve(const struct sshbuf *buf, size_t len);
133 * Preallocates len additional bytes in buf.
134 * Useful for cases where the caller knows how many bytes will ultimately be
135 * required to avoid realloc in the buffer code.
136 * Returns 0 on success, or a negative SSH_ERR_* error code on failure.
138 int sshbuf_allocate(struct sshbuf *buf, size_t len);
141 * Reserve len bytes in buf.
142 * Returns 0 on success and a pointer to the first reserved byte via the
143 * optional dpp parameter or a negative * SSH_ERR_* error code on failure.
145 int sshbuf_reserve(struct sshbuf *buf, size_t len, u_char **dpp);
148 * Consume len bytes from the start of buf
149 * Returns 0 on success, or a negative SSH_ERR_* error code on failure.
151 int sshbuf_consume(struct sshbuf *buf, size_t len);
154 * Consume len bytes from the end of buf
155 * Returns 0 on success, or a negative SSH_ERR_* error code on failure.
157 int sshbuf_consume_end(struct sshbuf *buf, size_t len);
159 /* Extract or deposit some bytes */
160 int sshbuf_get(struct sshbuf *buf, void *v, size_t len);
161 int sshbuf_put(struct sshbuf *buf, const void *v, size_t len);
162 int sshbuf_putb(struct sshbuf *buf, const struct sshbuf *v);
164 /* Append using a printf(3) format */
165 int sshbuf_putf(struct sshbuf *buf, const char *fmt, ...)
166 __attribute__((format(printf, 2, 3)));
167 int sshbuf_putfv(struct sshbuf *buf, const char *fmt, va_list ap);
169 /* Functions to extract or store big-endian words of various sizes */
170 int sshbuf_get_u64(struct sshbuf *buf, u_int64_t *valp);
171 int sshbuf_get_u32(struct sshbuf *buf, u_int32_t *valp);
172 int sshbuf_get_u16(struct sshbuf *buf, u_int16_t *valp);
173 int sshbuf_get_u8(struct sshbuf *buf, u_char *valp);
174 int sshbuf_put_u64(struct sshbuf *buf, u_int64_t val);
175 int sshbuf_put_u32(struct sshbuf *buf, u_int32_t val);
176 int sshbuf_put_u16(struct sshbuf *buf, u_int16_t val);
177 int sshbuf_put_u8(struct sshbuf *buf, u_char val);
179 #if defined(__FreeBSD__) && defined(__i386__)
180 #define sshbuf_get_time(b, vp) sshbuf_get_u32((b), (u_int32_t *)(vp))
181 #define sshbuf_put_time(b, v) sshbuf_put_u32((b), (u_int32_t)(v))
183 #define sshbuf_get_time(b, vp) sshbuf_get_u64((b), (u_int64_t *)(vp))
184 #define sshbuf_put_time(b, v) sshbuf_put_u64((b), (u_int64_t)(v))
188 * Functions to extract or store SSH wire encoded strings (u32 len || data)
189 * The "cstring" variants admit no \0 characters in the string contents.
190 * Caller must free *valp.
192 int sshbuf_get_string(struct sshbuf *buf, u_char **valp, size_t *lenp);
193 int sshbuf_get_cstring(struct sshbuf *buf, char **valp, size_t *lenp);
194 int sshbuf_get_stringb(struct sshbuf *buf, struct sshbuf *v);
195 int sshbuf_put_string(struct sshbuf *buf, const void *v, size_t len);
196 int sshbuf_put_cstring(struct sshbuf *buf, const char *v);
197 int sshbuf_put_stringb(struct sshbuf *buf, const struct sshbuf *v);
200 * "Direct" variant of sshbuf_get_string, returns pointer into the sshbuf to
201 * avoid an malloc+memcpy. The pointer is guaranteed to be valid until the
202 * next sshbuf-modifying function call. Caller does not free.
204 int sshbuf_get_string_direct(struct sshbuf *buf, const u_char **valp,
207 /* Skip past a string */
208 #define sshbuf_skip_string(buf) sshbuf_get_string_direct(buf, NULL, NULL)
210 /* Another variant: "peeks" into the buffer without modifying it */
211 int sshbuf_peek_string_direct(const struct sshbuf *buf, const u_char **valp,
213 /* XXX peek_u8 / peek_u32 */
216 * Functions to extract or store SSH wire encoded bignums and elliptic
219 int sshbuf_put_bignum2_bytes(struct sshbuf *buf, const void *v, size_t len);
220 int sshbuf_get_bignum2_bytes_direct(struct sshbuf *buf,
221 const u_char **valp, size_t *lenp);
223 int sshbuf_get_bignum2(struct sshbuf *buf, BIGNUM *v);
224 int sshbuf_get_bignum1(struct sshbuf *buf, BIGNUM *v);
225 int sshbuf_put_bignum2(struct sshbuf *buf, const BIGNUM *v);
226 int sshbuf_put_bignum1(struct sshbuf *buf, const BIGNUM *v);
227 # ifdef OPENSSL_HAS_ECC
228 int sshbuf_get_ec(struct sshbuf *buf, EC_POINT *v, const EC_GROUP *g);
229 int sshbuf_get_eckey(struct sshbuf *buf, EC_KEY *v);
230 int sshbuf_put_ec(struct sshbuf *buf, const EC_POINT *v, const EC_GROUP *g);
231 int sshbuf_put_eckey(struct sshbuf *buf, const EC_KEY *v);
232 # endif /* OPENSSL_HAS_ECC */
233 #endif /* WITH_OPENSSL */
235 /* Dump the contents of the buffer in a human-readable format */
236 void sshbuf_dump(struct sshbuf *buf, FILE *f);
238 /* Dump specified memory in a human-readable format */
239 void sshbuf_dump_data(const void *s, size_t len, FILE *f);
241 /* Return the hexadecimal representation of the contents of the buffer */
242 char *sshbuf_dtob16(struct sshbuf *buf);
244 /* Encode the contents of the buffer as base64 */
245 char *sshbuf_dtob64(struct sshbuf *buf);
247 /* Decode base64 data and append it to the buffer */
248 int sshbuf_b64tod(struct sshbuf *buf, const char *b64);
251 * Duplicate the contents of a buffer to a string (caller to free).
252 * Returns NULL on buffer error, or if the buffer contains a premature
255 char *sshbuf_dup_string(struct sshbuf *buf);
260 int sshbuf_put_passwd(struct sshbuf *buf, const struct passwd *pwent);
265 struct passwd *sshbuf_get_passwd(struct sshbuf *buf);
268 * free struct passwd obtained from sshbuf_get_passwd.
270 void sshbuf_free_passwd(struct passwd *pwent);
272 /* Macros for decoding/encoding integers */
273 #define PEEK_U64(p) \
274 (((u_int64_t)(((const u_char *)(p))[0]) << 56) | \
275 ((u_int64_t)(((const u_char *)(p))[1]) << 48) | \
276 ((u_int64_t)(((const u_char *)(p))[2]) << 40) | \
277 ((u_int64_t)(((const u_char *)(p))[3]) << 32) | \
278 ((u_int64_t)(((const u_char *)(p))[4]) << 24) | \
279 ((u_int64_t)(((const u_char *)(p))[5]) << 16) | \
280 ((u_int64_t)(((const u_char *)(p))[6]) << 8) | \
281 (u_int64_t)(((const u_char *)(p))[7]))
282 #define PEEK_U32(p) \
283 (((u_int32_t)(((const u_char *)(p))[0]) << 24) | \
284 ((u_int32_t)(((const u_char *)(p))[1]) << 16) | \
285 ((u_int32_t)(((const u_char *)(p))[2]) << 8) | \
286 (u_int32_t)(((const u_char *)(p))[3]))
287 #define PEEK_U16(p) \
288 (((u_int16_t)(((const u_char *)(p))[0]) << 8) | \
289 (u_int16_t)(((const u_char *)(p))[1]))
291 #define POKE_U64(p, v) \
293 const u_int64_t __v = (v); \
294 ((u_char *)(p))[0] = (__v >> 56) & 0xff; \
295 ((u_char *)(p))[1] = (__v >> 48) & 0xff; \
296 ((u_char *)(p))[2] = (__v >> 40) & 0xff; \
297 ((u_char *)(p))[3] = (__v >> 32) & 0xff; \
298 ((u_char *)(p))[4] = (__v >> 24) & 0xff; \
299 ((u_char *)(p))[5] = (__v >> 16) & 0xff; \
300 ((u_char *)(p))[6] = (__v >> 8) & 0xff; \
301 ((u_char *)(p))[7] = __v & 0xff; \
303 #define POKE_U32(p, v) \
305 const u_int32_t __v = (v); \
306 ((u_char *)(p))[0] = (__v >> 24) & 0xff; \
307 ((u_char *)(p))[1] = (__v >> 16) & 0xff; \
308 ((u_char *)(p))[2] = (__v >> 8) & 0xff; \
309 ((u_char *)(p))[3] = __v & 0xff; \
311 #define POKE_U16(p, v) \
313 const u_int16_t __v = (v); \
314 ((u_char *)(p))[0] = (__v >> 8) & 0xff; \
315 ((u_char *)(p))[1] = __v & 0xff; \
318 /* Internal definitions follow. Exposed for regress tests */
319 #ifdef SSHBUF_INTERNAL
322 * Return the allocation size of buf
324 size_t sshbuf_alloc(const struct sshbuf *buf);
327 * Increment the reference count of buf.
329 int sshbuf_set_parent(struct sshbuf *child, struct sshbuf *parent);
332 * Return the parent buffer of buf, or NULL if it has no parent.
334 const struct sshbuf *sshbuf_parent(const struct sshbuf *buf);
337 * Return the reference count of buf
339 u_int sshbuf_refcount(const struct sshbuf *buf);
341 # define SSHBUF_SIZE_INIT 256 /* Initial allocation */
342 # define SSHBUF_SIZE_INC 256 /* Preferred increment length */
343 # define SSHBUF_PACK_MIN 8192 /* Minimim packable offset */
345 /* # define SSHBUF_ABORT abort */
346 /* # define SSHBUF_DEBUG */
348 # ifndef SSHBUF_ABORT
349 # define SSHBUF_ABORT()
353 # define SSHBUF_TELL(what) do { \
354 printf("%s:%d %s: %s size %zu alloc %zu off %zu max %zu\n", \
355 __FILE__, __LINE__, __func__, what, \
356 buf->size, buf->alloc, buf->off, buf->max_size); \
359 # define SSHBUF_DBG(x) do { \
360 printf("%s:%d %s: ", __FILE__, __LINE__, __func__); \
366 # define SSHBUF_TELL(what)
367 # define SSHBUF_DBG(x)
369 #endif /* SSHBUF_INTERNAL */
371 #endif /* _SSHBUF_H */