boringssl/crypto/mem.h
Adam Langley 01797e309f psk_client_callback, 128-byte id bug.
Fix a bug in handling of 128 byte long PSK identity in
psk_client_callback.

OpenSSL supports PSK identities of up to (and including) 128 bytes in
length. PSK identity is obtained via the psk_client_callback,
implementors of which are expected to provide a NULL-terminated
identity. However, the callback is invoked with only 128 bytes of
storage thus making it impossible to return a 128 byte long identity and
the required additional NULL byte.

This CL fixes the issue by passing in a 129 byte long buffer into the
psk_client_callback. As a safety precaution, this CL also zeroes out the
buffer before passing it into the callback, uses strnlen for obtaining
the length of the identity returned by the callback, and aborts the
handshake if the identity (without the NULL terminator) is longer than
128 bytes.
2014-06-20 13:17:37 -07:00

130 lines
5.6 KiB
C

/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) * All rights reserved.
*
* This package is an SSL implementation written
* by Eric Young (eay@cryptsoft.com).
* The implementation was written so as to conform with Netscapes SSL.
*
* This library is free for commercial and non-commercial use as long as
* the following conditions are aheared to. The following conditions
* apply to all code found in this distribution, be it the RC4, RSA,
* lhash, DES, etc., code; not just the SSL code. The SSL documentation
* included with this distribution is covered by the same copyright terms
* except that the holder is Tim Hudson (tjh@cryptsoft.com).
*
* Copyright remains Eric Young's, and as such any Copyright notices in
* the code are not to be removed.
* If this package is used in a product, Eric Young should be given attribution
* as the author of the parts of the library used.
* This can be in the form of a textual message at program startup or
* in documentation (online or textual) provided with the package.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* "This product includes cryptographic software written by
* Eric Young (eay@cryptsoft.com)"
* The word 'cryptographic' can be left out if the rouines from the library
* being used are not cryptographic related :-).
* 4. If you include any Windows specific code (or a derivative thereof) from
* the apps directory (application code) you must include an acknowledgement:
* "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
*
* THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* The licence and distribution terms for any publically available version or
* derivative of this code cannot be changed. i.e. this code cannot simply be
* copied and put under another distribution licence
* [including the GNU Public Licence.] */
#ifndef OPENSSL_HEADER_MEM_H
#define OPENSSL_HEADER_MEM_H
#include <openssl/base.h>
#include <stdarg.h>
#if defined(__cplusplus)
extern "C" {
#endif
/* OpenSSL has, historically, had a complex set of malloc debugging options.
* However, that was written in a time before Valgrind and ASAN. Since we now
* have those tools, the OpenSSL allocation functions are simply macros around
* the standard memory functions. */
#define OPENSSL_malloc malloc
#define OPENSSL_realloc realloc
#define OPENSSL_free free
/* OPENSSL_realloc_clean acts like |realloc|, but clears the previous memory
* buffer. Because this is implemented as a wrapper around |malloc|, it needs
* to be given the size of the buffer pointed to by |ptr|. */
void *OPENSSL_realloc_clean(void *ptr, size_t old_size, size_t new_size);
/* OPENSSL_cleanse zeros out |len| bytes of memory at |ptr|. This is similar to
* |memset_s| from C11. */
void OPENSSL_cleanse(void *ptr, size_t len);
/* CRYPTO_memcmp returns zero iff the |len| bytes at |a| and |b| are equal. It
* takes an amount of time dependent on |len|, but independent of the contents
* of |a| and |b|. Unlike memcmp, it cannot be used to put elements into a
* defined order as the return value when a != b is undefined, other than to be
* non-zero. */
int CRYPTO_memcmp(const void *a, const void *b, size_t len);
/* OPENSSL_hash32 implements the 32 bit, FNV-1a hash. */
uint32_t OPENSSL_hash32(const void *ptr, size_t len);
/* OPENSSL_strdup has the same behaviour as strdup(3). */
char *OPENSSL_strdup(const char *s);
/* OPENSSL_strnlen has the same behaviour as strnlen(3). */
size_t OPENSSL_strnlen(const char *s, size_t len);
/* DECIMAL_SIZE returns an upper bound for the length of the decimal
* representation of the given type. */
#define DECIMAL_SIZE(type) ((sizeof(type)*8+2)/3+1)
/* Printf functions.
*
* These functions are either OpenSSL wrappers for standard functions (i.e.
* |BIO_snprintf| and |BIO_vsnprintf|) which don't exist in C89, or are
* versions of printf functions that output to a BIO rather than a FILE. */
#ifdef __GNUC__
#define __bio_h__attr__ __attribute__
#else
#define __bio_h__attr__(x)
#endif
int BIO_snprintf(char *buf, size_t n, const char *format, ...)
__bio_h__attr__((__format__(__printf__, 3, 4)));
int BIO_vsnprintf(char *buf, size_t n, const char *format, va_list args)
__bio_h__attr__((__format__(__printf__, 3, 0)));
#undef __bio_h__attr__
#if defined(__cplusplus)
} /* extern C */
#endif
#endif /* OPENSSL_HEADER_MEM_H */