d/freebsd-dev
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
396a8479b0
freebsd-dev/crypto/openssh/sshbuf.h
Ed Maste 19261079b7 openssh: update to OpenSSH v8.7p1 
Some notable changes, from upstream's release notes:

- sshd(8): Remove support for obsolete "host/port" syntax.
- ssh(1): When prompting whether to record a new host key, accept the key
  fingerprint as a synonym for "yes".
- ssh-keygen(1): when acting as a CA and signing certificates with an RSA
  key, default to using the rsa-sha2-512 signature algorithm.
- ssh(1), sshd(8), ssh-keygen(1): this release removes the "ssh-rsa"
  (RSA/SHA1) algorithm from those accepted for certificate signatures.
- ssh-sk-helper(8): this is a new binary. It is used by the FIDO/U2F
  support to provide address-space isolation for token middleware
  libraries (including the internal one).
- ssh(1): this release enables UpdateHostkeys by default subject to some
  conservative preconditions.
- scp(1): this release changes the behaviour of remote to remote copies
  (e.g. "scp host-a:/path host-b:") to transfer through the local host
  by default.
- scp(1): experimental support for transfers using the SFTP protocol as
  a replacement for the venerable SCP/RCP protocol that it has
  traditionally used.

Additional integration work is needed to support FIDO/U2F in the base
system.

Deprecation Notice
------------------

OpenSSH will disable the ssh-rsa signature scheme by default in the
next release.

Reviewed by:	imp
MFC after:	1 month
Relnotes:	Yes
Sponsored by:	The FreeBSD Foundation
Differential Revision:	https://reviews.freebsd.org/D29985
2021-09-07 21:05:51 -04:00

412 lines
14 KiB
C
Raw Blame History

/* $OpenBSD: sshbuf.h,v 1.23 2020/06/22 05:54:10 djm Exp $ */
/*
* Copyright (c) 2011 Damien Miller
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#ifndef _SSHBUF_H
#define _SSHBUF_H
#include <sys/types.h>
#include <stdarg.h>
#include <stdio.h>
#ifdef WITH_OPENSSL
# include <openssl/bn.h>
# ifdef OPENSSL_HAS_ECC
# include <openssl/ec.h>
# endif /* OPENSSL_HAS_ECC */
#endif /* WITH_OPENSSL */
#define SSHBUF_SIZE_MAX 0x8000000 /* Hard maximum size */
#define SSHBUF_REFS_MAX 0x100000 /* Max child buffers */
#define SSHBUF_MAX_BIGNUM (16384 / 8) /* Max bignum *bytes* */
#define SSHBUF_MAX_ECPOINT ((528 * 2 / 8) + 1) /* Max EC point *bytes* */
/*
* NB. do not depend on the internals of this. It will be made opaque
* one day.
*/
struct sshbuf {
u_char *d; /* Data */
const u_char *cd; /* Const data */
size_t off; /* First available byte is buf->d + buf->off */
size_t size; /* Last byte is buf->d + buf->size - 1 */
size_t max_size; /* Maximum size of buffer */
size_t alloc; /* Total bytes allocated to buf->d */
int readonly; /* Refers to external, const data */
int dont_free; /* Kludge to support sshbuf_init */
u_int refcount; /* Tracks self and number of child buffers */
struct sshbuf *parent; /* If child, pointer to parent */
};
/*
* Create a new sshbuf buffer.
* Returns pointer to buffer on success, or NULL on allocation failure.
*/
struct sshbuf *sshbuf_new(void);
/*
* Create a new, read-only sshbuf buffer from existing data.
* Returns pointer to buffer on success, or NULL on allocation failure.
*/
struct sshbuf *sshbuf_from(const void *blob, size_t len);
/*
* Create a new, read-only sshbuf buffer from the contents of an existing
* buffer. The contents of "buf" must not change in the lifetime of the
* resultant buffer.
* Returns pointer to buffer on success, or NULL on allocation failure.
*/
struct sshbuf *sshbuf_fromb(struct sshbuf *buf);
/*
* Create a new, read-only sshbuf buffer from the contents of a string in
* an existing buffer (the string is consumed in the process).
* The contents of "buf" must not change in the lifetime of the resultant
* buffer.
* Returns pointer to buffer on success, or NULL on allocation failure.
*/
int sshbuf_froms(struct sshbuf *buf, struct sshbuf **bufp);
/*
* Clear and free buf
*/
void sshbuf_free(struct sshbuf *buf);
/*
* Reset buf, clearing its contents. NB. max_size is preserved.
*/
void sshbuf_reset(struct sshbuf *buf);
/*
* Return the maximum size of buf
*/
size_t sshbuf_max_size(const struct sshbuf *buf);
/*
* Set the maximum size of buf
* Returns 0 on success, or a negative SSH_ERR_* error code on failure.
*/
int sshbuf_set_max_size(struct sshbuf *buf, size_t max_size);
/*
* Returns the length of data in buf
*/
size_t sshbuf_len(const struct sshbuf *buf);
/*
* Returns number of bytes left in buffer before hitting max_size.
*/
size_t sshbuf_avail(const struct sshbuf *buf);
/*
* Returns a read-only pointer to the start of the data in buf
*/
const u_char *sshbuf_ptr(const struct sshbuf *buf);
/*
* Returns a mutable pointer to the start of the data in buf, or
* NULL if the buffer is read-only.
*/
u_char *sshbuf_mutable_ptr(const struct sshbuf *buf);
/*
* Check whether a reservation of size len will succeed in buf
* Safer to use than direct comparisons again sshbuf_avail as it copes
* with unsigned overflows correctly.
* Returns 0 on success, or a negative SSH_ERR_* error code on failure.
*/
int sshbuf_check_reserve(const struct sshbuf *buf, size_t len);
/*
* Preallocates len additional bytes in buf.
* Useful for cases where the caller knows how many bytes will ultimately be
* required to avoid realloc in the buffer code.
* Returns 0 on success, or a negative SSH_ERR_* error code on failure.
*/
int sshbuf_allocate(struct sshbuf *buf, size_t len);
/*
* Reserve len bytes in buf.
* Returns 0 on success and a pointer to the first reserved byte via the
* optional dpp parameter or a negative SSH_ERR_* error code on failure.
*/
int sshbuf_reserve(struct sshbuf *buf, size_t len, u_char **dpp);
/*
* Consume len bytes from the start of buf
* Returns 0 on success, or a negative SSH_ERR_* error code on failure.
*/
int sshbuf_consume(struct sshbuf *buf, size_t len);
/*
* Consume len bytes from the end of buf
* Returns 0 on success, or a negative SSH_ERR_* error code on failure.
*/
int sshbuf_consume_end(struct sshbuf *buf, size_t len);
/* Extract or deposit some bytes */
int sshbuf_get(struct sshbuf *buf, void *v, size_t len);
int sshbuf_put(struct sshbuf *buf, const void *v, size_t len);
int sshbuf_putb(struct sshbuf *buf, const struct sshbuf *v);
/* Append using a printf(3) format */
int sshbuf_putf(struct sshbuf *buf, const char *fmt, ...)
__attribute__((format(printf, 2, 3)));
int sshbuf_putfv(struct sshbuf *buf, const char *fmt, va_list ap);
/* Functions to extract or store big-endian words of various sizes */
int sshbuf_get_u64(struct sshbuf *buf, u_int64_t *valp);
int sshbuf_get_u32(struct sshbuf *buf, u_int32_t *valp);
int sshbuf_get_u16(struct sshbuf *buf, u_int16_t *valp);
int sshbuf_get_u8(struct sshbuf *buf, u_char *valp);
int sshbuf_put_u64(struct sshbuf *buf, u_int64_t val);
int sshbuf_put_u32(struct sshbuf *buf, u_int32_t val);
int sshbuf_put_u16(struct sshbuf *buf, u_int16_t val);
int sshbuf_put_u8(struct sshbuf *buf, u_char val);
/* Functions to peek at the contents of a buffer without modifying it. */
int sshbuf_peek_u64(const struct sshbuf *buf, size_t offset,
u_int64_t *valp);
int sshbuf_peek_u32(const struct sshbuf *buf, size_t offset,
u_int32_t *valp);
int sshbuf_peek_u16(const struct sshbuf *buf, size_t offset,
u_int16_t *valp);
int sshbuf_peek_u8(const struct sshbuf *buf, size_t offset,
u_char *valp);
/*
* Functions to poke values into an existing buffer (e.g. a length header
* to a packet). The destination bytes must already exist in the buffer.
*/
int sshbuf_poke_u64(struct sshbuf *buf, size_t offset, u_int64_t val);
int sshbuf_poke_u32(struct sshbuf *buf, size_t offset, u_int32_t val);
int sshbuf_poke_u16(struct sshbuf *buf, size_t offset, u_int16_t val);
int sshbuf_poke_u8(struct sshbuf *buf, size_t offset, u_char val);
int sshbuf_poke(struct sshbuf *buf, size_t offset, void *v, size_t len);
/*
* Functions to extract or store SSH wire encoded strings (u32 len || data)
* The "cstring" variants admit no \0 characters in the string contents.
* Caller must free *valp.
*/
int sshbuf_get_string(struct sshbuf *buf, u_char **valp, size_t *lenp);
int sshbuf_get_cstring(struct sshbuf *buf, char **valp, size_t *lenp);
int sshbuf_get_stringb(struct sshbuf *buf, struct sshbuf *v);
int sshbuf_put_string(struct sshbuf *buf, const void *v, size_t len);
int sshbuf_put_cstring(struct sshbuf *buf, const char *v);
int sshbuf_put_stringb(struct sshbuf *buf, const struct sshbuf *v);
/*
* "Direct" variant of sshbuf_get_string, returns pointer into the sshbuf to
* avoid an malloc+memcpy. The pointer is guaranteed to be valid until the
* next sshbuf-modifying function call. Caller does not free.
*/
int sshbuf_get_string_direct(struct sshbuf *buf, const u_char **valp,
size_t *lenp);
/* Skip past a string */
#define sshbuf_skip_string(buf) sshbuf_get_string_direct(buf, NULL, NULL)
/* Another variant: "peeks" into the buffer without modifying it */
int sshbuf_peek_string_direct(const struct sshbuf *buf, const u_char **valp,
size_t *lenp);
/*
* Functions to extract or store SSH wire encoded bignums and elliptic
* curve points.
*/
int sshbuf_put_bignum2_bytes(struct sshbuf *buf, const void *v, size_t len);
int sshbuf_get_bignum2_bytes_direct(struct sshbuf *buf,
const u_char **valp, size_t *lenp);
#ifdef WITH_OPENSSL
int sshbuf_get_bignum2(struct sshbuf *buf, BIGNUM **valp);
int sshbuf_put_bignum2(struct sshbuf *buf, const BIGNUM *v);
# ifdef OPENSSL_HAS_ECC
int sshbuf_get_ec(struct sshbuf *buf, EC_POINT *v, const EC_GROUP *g);
int sshbuf_get_eckey(struct sshbuf *buf, EC_KEY *v);
int sshbuf_put_ec(struct sshbuf *buf, const EC_POINT *v, const EC_GROUP *g);
int sshbuf_put_eckey(struct sshbuf *buf, const EC_KEY *v);
# endif /* OPENSSL_HAS_ECC */
#endif /* WITH_OPENSSL */
/* Dump the contents of the buffer in a human-readable format */
void sshbuf_dump(const struct sshbuf *buf, FILE *f);
/* Dump specified memory in a human-readable format */
void sshbuf_dump_data(const void *s, size_t len, FILE *f);
/* Return the hexadecimal representation of the contents of the buffer */
char *sshbuf_dtob16(struct sshbuf *buf);
/* Encode the contents of the buffer as base64 */
char *sshbuf_dtob64_string(const struct sshbuf *buf, int wrap);
int sshbuf_dtob64(const struct sshbuf *d, struct sshbuf *b64, int wrap);
/* RFC4648 "base64url" encoding variant */
int sshbuf_dtourlb64(const struct sshbuf *d, struct sshbuf *b64, int wrap);
/* Decode base64 data and append it to the buffer */
int sshbuf_b64tod(struct sshbuf *buf, const char *b64);
/*
* Tests whether the buffer contains the specified byte sequence at the
* specified offset. Returns 0 on successful match, or a ssherr.h code
* otherwise. SSH_ERR_INVALID_FORMAT indicates sufficient bytes were
* present but the buffer contents did not match those supplied. Zero-
* length comparisons are not allowed.
*
* If sufficient data is present to make a comparison, then it is
* performed with timing independent of the value of the data. If
* insufficient data is present then the comparison is not attempted at
* all.
*/
int sshbuf_cmp(const struct sshbuf *b, size_t offset,
const void *s, size_t len);
/*
* Searches the buffer for the specified string. Returns 0 on success
* and updates *offsetp with the offset of the first match, relative to
* the start of the buffer. Otherwise sshbuf_find will return a ssherr.h
* error code. SSH_ERR_INVALID_FORMAT indicates sufficient bytes were
* present in the buffer for a match to be possible but none was found.
* Searches for zero-length data are not allowed.
*/
int
sshbuf_find(const struct sshbuf *b, size_t start_offset,
const void *s, size_t len, size_t *offsetp);
/*
* Duplicate the contents of a buffer to a string (caller to free).
* Returns NULL on buffer error, or if the buffer contains a premature
* nul character.
*/
char *sshbuf_dup_string(struct sshbuf *buf);
/*
* Fill a buffer from a file descriptor or filename. Both allocate the
* buffer for the caller.
*/
int sshbuf_load_fd(int, struct sshbuf **)
__attribute__((__nonnull__ (2)));
int sshbuf_load_file(const char *, struct sshbuf **)
__attribute__((__nonnull__ (2)));
/*
* Write a buffer to a path, creating/truncating as needed (mode 0644,
* subject to umask). The buffer contents are not modified.
*/
int sshbuf_write_file(const char *path, struct sshbuf *buf)
__attribute__((__nonnull__ (2)));
/* Macros for decoding/encoding integers */
#define PEEK_U64(p) \
(((u_int64_t)(((const u_char *)(p))[0]) << 56) | \
((u_int64_t)(((const u_char *)(p))[1]) << 48) | \
((u_int64_t)(((const u_char *)(p))[2]) << 40) | \
((u_int64_t)(((const u_char *)(p))[3]) << 32) | \
((u_int64_t)(((const u_char *)(p))[4]) << 24) | \
((u_int64_t)(((const u_char *)(p))[5]) << 16) | \
((u_int64_t)(((const u_char *)(p))[6]) << 8) | \
(u_int64_t)(((const u_char *)(p))[7]))
#define PEEK_U32(p) \
(((u_int32_t)(((const u_char *)(p))[0]) << 24) | \
((u_int32_t)(((const u_char *)(p))[1]) << 16) | \
((u_int32_t)(((const u_char *)(p))[2]) << 8) | \
(u_int32_t)(((const u_char *)(p))[3]))
#define PEEK_U16(p) \
(((u_int16_t)(((const u_char *)(p))[0]) << 8) | \
(u_int16_t)(((const u_char *)(p))[1]))
#define POKE_U64(p, v) \
do { \
const u_int64_t __v = (v); \
((u_char *)(p))[0] = (__v >> 56) & 0xff; \
((u_char *)(p))[1] = (__v >> 48) & 0xff; \
((u_char *)(p))[2] = (__v >> 40) & 0xff; \
((u_char *)(p))[3] = (__v >> 32) & 0xff; \
((u_char *)(p))[4] = (__v >> 24) & 0xff; \
((u_char *)(p))[5] = (__v >> 16) & 0xff; \
((u_char *)(p))[6] = (__v >> 8) & 0xff; \
((u_char *)(p))[7] = __v & 0xff; \
} while (0)
#define POKE_U32(p, v) \
do { \
const u_int32_t __v = (v); \
((u_char *)(p))[0] = (__v >> 24) & 0xff; \
((u_char *)(p))[1] = (__v >> 16) & 0xff; \
((u_char *)(p))[2] = (__v >> 8) & 0xff; \
((u_char *)(p))[3] = __v & 0xff; \
} while (0)
#define POKE_U16(p, v) \
do { \
const u_int16_t __v = (v); \
((u_char *)(p))[0] = (__v >> 8) & 0xff; \
((u_char *)(p))[1] = __v & 0xff; \
} while (0)
/* Internal definitions follow. Exposed for regress tests */
#ifdef SSHBUF_INTERNAL
/*
* Return the allocation size of buf
*/
size_t sshbuf_alloc(const struct sshbuf *buf);
/*
* Increment the reference count of buf.
*/
int sshbuf_set_parent(struct sshbuf *child, struct sshbuf *parent);
/*
* Return the parent buffer of buf, or NULL if it has no parent.
*/
const struct sshbuf *sshbuf_parent(const struct sshbuf *buf);
/*
* Return the reference count of buf
*/
u_int sshbuf_refcount(const struct sshbuf *buf);
# define SSHBUF_SIZE_INIT 256 /* Initial allocation */
# define SSHBUF_SIZE_INC 256 /* Preferred increment length */
# define SSHBUF_PACK_MIN 8192 /* Minimim packable offset */
/* # define SSHBUF_ABORT abort */
/* # define SSHBUF_DEBUG */
# ifndef SSHBUF_ABORT
# define SSHBUF_ABORT()
# endif
# ifdef SSHBUF_DEBUG
# define SSHBUF_TELL(what) do { \
printf("%s:%d %s: %s size %zu alloc %zu off %zu max %zu\n", \
__FILE__, __LINE__, __func__, what, \
buf->size, buf->alloc, buf->off, buf->max_size); \
fflush(stdout); \
} while (0)
# define SSHBUF_DBG(x) do { \
printf("%s:%d %s: ", __FILE__, __LINE__, __func__); \
printf x; \
printf("\n"); \
fflush(stdout); \
} while (0)
# else
# define SSHBUF_TELL(what)
# define SSHBUF_DBG(x)
# endif
#endif /* SSHBUF_INTERNAL */
#endif /* _SSHBUF_H */
Reference in New Issue View Git Blame Copy Permalink