| /* $OpenBSD: sshbuf.h,v 1.12 2019/01/21 09:52:25 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 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); |
| /* XXX peek_u8 / peek_u32 */ |
| |
| /* |
| * 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 *v); |
| 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(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(struct sshbuf *buf); |
| |
| /* Decode base64 data and append it to the buffer */ |
| int sshbuf_b64tod(struct sshbuf *buf, const char *b64); |
| |
| /* |
| * 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); |
| |
| /* 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 */ |