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Diffstat (limited to 'thirdparty/mbedtls/library/entropy_poll.c')
| -rw-r--r-- | thirdparty/mbedtls/library/entropy_poll.c | 268 |
1 files changed, 268 insertions, 0 deletions
diff --git a/thirdparty/mbedtls/library/entropy_poll.c b/thirdparty/mbedtls/library/entropy_poll.c new file mode 100644 index 0000000000..a116e605d2 --- /dev/null +++ b/thirdparty/mbedtls/library/entropy_poll.c @@ -0,0 +1,268 @@ +/* + * Platform-specific and custom entropy polling functions + * + * Copyright (C) 2006-2016, ARM Limited, All Rights Reserved + * SPDX-License-Identifier: Apache-2.0 + * + * Licensed under the Apache License, Version 2.0 (the "License"); you may + * not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT + * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + * + * This file is part of mbed TLS (https://tls.mbed.org) + */ + +#if !defined(MBEDTLS_CONFIG_FILE) +#include "mbedtls/config.h" +#else +#include MBEDTLS_CONFIG_FILE +#endif + +#if defined(MBEDTLS_ENTROPY_C) + +#include "mbedtls/entropy.h" +#include "mbedtls/entropy_poll.h" + +#if defined(MBEDTLS_TIMING_C) +#include <string.h> +#include "mbedtls/timing.h" +#endif +#if defined(MBEDTLS_HAVEGE_C) +#include "mbedtls/havege.h" +#endif +#if defined(MBEDTLS_ENTROPY_NV_SEED) +#include "mbedtls/platform.h" +#endif + +#if !defined(MBEDTLS_NO_PLATFORM_ENTROPY) + +#if !defined(unix) && !defined(__unix__) && !defined(__unix) && \ + !defined(__APPLE__) && !defined(_WIN32) +#error "Platform entropy sources only work on Unix and Windows, see MBEDTLS_NO_PLATFORM_ENTROPY in config.h" +#endif + +#if defined(_WIN32) && !defined(EFIX64) && !defined(EFI32) + +#if !defined(_WIN32_WINNT) +#define _WIN32_WINNT 0x0400 +#endif +#include <windows.h> +#include <wincrypt.h> + +int mbedtls_platform_entropy_poll( void *data, unsigned char *output, size_t len, + size_t *olen ) +{ + HCRYPTPROV provider; + ((void) data); + *olen = 0; + + if( CryptAcquireContext( &provider, NULL, NULL, + PROV_RSA_FULL, CRYPT_VERIFYCONTEXT ) == FALSE ) + { + return( MBEDTLS_ERR_ENTROPY_SOURCE_FAILED ); + } + + if( CryptGenRandom( provider, (DWORD) len, output ) == FALSE ) + { + CryptReleaseContext( provider, 0 ); + return( MBEDTLS_ERR_ENTROPY_SOURCE_FAILED ); + } + + CryptReleaseContext( provider, 0 ); + *olen = len; + + return( 0 ); +} +#else /* _WIN32 && !EFIX64 && !EFI32 */ + +/* + * Test for Linux getrandom() support. + * Since there is no wrapper in the libc yet, use the generic syscall wrapper + * available in GNU libc and compatible libc's (eg uClibc). + */ +#if defined(__linux__) && defined(__GLIBC__) +#include <unistd.h> +#include <sys/syscall.h> +#if defined(SYS_getrandom) +#define HAVE_GETRANDOM + +static int getrandom_wrapper( void *buf, size_t buflen, unsigned int flags ) +{ + /* MemSan cannot understand that the syscall writes to the buffer */ +#if defined(__has_feature) +#if __has_feature(memory_sanitizer) + memset( buf, 0, buflen ); +#endif +#endif + + return( syscall( SYS_getrandom, buf, buflen, flags ) ); +} + +#include <sys/utsname.h> +/* Check if version is at least 3.17.0 */ +static int check_version_3_17_plus( void ) +{ + int minor; + struct utsname un; + const char *ver; + + /* Get version information */ + uname(&un); + ver = un.release; + + /* Check major version; assume a single digit */ + if( ver[0] < '3' || ver[0] > '9' || ver [1] != '.' ) + return( -1 ); + + if( ver[0] - '0' > 3 ) + return( 0 ); + + /* Ok, so now we know major == 3, check minor. + * Assume 1 or 2 digits. */ + if( ver[2] < '0' || ver[2] > '9' ) + return( -1 ); + + minor = ver[2] - '0'; + + if( ver[3] >= '0' && ver[3] <= '9' ) + minor = 10 * minor + ver[3] - '0'; + else if( ver [3] != '.' ) + return( -1 ); + + if( minor < 17 ) + return( -1 ); + + return( 0 ); +} +static int has_getrandom = -1; +#endif /* SYS_getrandom */ +#endif /* __linux__ */ + +#include <stdio.h> + +int mbedtls_platform_entropy_poll( void *data, + unsigned char *output, size_t len, size_t *olen ) +{ + FILE *file; + size_t read_len; + ((void) data); + +#if defined(HAVE_GETRANDOM) + if( has_getrandom == -1 ) + has_getrandom = ( check_version_3_17_plus() == 0 ); + + if( has_getrandom ) + { + int ret; + + if( ( ret = getrandom_wrapper( output, len, 0 ) ) < 0 ) + return( MBEDTLS_ERR_ENTROPY_SOURCE_FAILED ); + + *olen = ret; + return( 0 ); + } +#endif /* HAVE_GETRANDOM */ + + *olen = 0; + + file = fopen( "/dev/urandom", "rb" ); + if( file == NULL ) + return( MBEDTLS_ERR_ENTROPY_SOURCE_FAILED ); + + read_len = fread( output, 1, len, file ); + if( read_len != len ) + { + fclose( file ); + return( MBEDTLS_ERR_ENTROPY_SOURCE_FAILED ); + } + + fclose( file ); + *olen = len; + + return( 0 ); +} +#endif /* _WIN32 && !EFIX64 && !EFI32 */ +#endif /* !MBEDTLS_NO_PLATFORM_ENTROPY */ + +#if defined(MBEDTLS_TEST_NULL_ENTROPY) +int mbedtls_null_entropy_poll( void *data, + unsigned char *output, size_t len, size_t *olen ) +{ + ((void) data); + ((void) output); + *olen = 0; + + if( len < sizeof(unsigned char) ) + return( 0 ); + + *olen = sizeof(unsigned char); + + return( 0 ); +} +#endif + +#if defined(MBEDTLS_TIMING_C) +int mbedtls_hardclock_poll( void *data, + unsigned char *output, size_t len, size_t *olen ) +{ + unsigned long timer = mbedtls_timing_hardclock(); + ((void) data); + *olen = 0; + + if( len < sizeof(unsigned long) ) + return( 0 ); + + memcpy( output, &timer, sizeof(unsigned long) ); + *olen = sizeof(unsigned long); + + return( 0 ); +} +#endif /* MBEDTLS_TIMING_C */ + +#if defined(MBEDTLS_HAVEGE_C) +int mbedtls_havege_poll( void *data, + unsigned char *output, size_t len, size_t *olen ) +{ + mbedtls_havege_state *hs = (mbedtls_havege_state *) data; + *olen = 0; + + if( mbedtls_havege_random( hs, output, len ) != 0 ) + return( MBEDTLS_ERR_ENTROPY_SOURCE_FAILED ); + + *olen = len; + + return( 0 ); +} +#endif /* MBEDTLS_HAVEGE_C */ + +#if defined(MBEDTLS_ENTROPY_NV_SEED) +int mbedtls_nv_seed_poll( void *data, + unsigned char *output, size_t len, size_t *olen ) +{ + unsigned char buf[MBEDTLS_ENTROPY_BLOCK_SIZE]; + size_t use_len = MBEDTLS_ENTROPY_BLOCK_SIZE; + ((void) data); + + memset( buf, 0, MBEDTLS_ENTROPY_BLOCK_SIZE ); + + if( mbedtls_nv_seed_read( buf, MBEDTLS_ENTROPY_BLOCK_SIZE ) < 0 ) + return( MBEDTLS_ERR_ENTROPY_SOURCE_FAILED ); + + if( len < use_len ) + use_len = len; + + memcpy( output, buf, use_len ); + *olen = use_len; + + return( 0 ); +} +#endif /* MBEDTLS_ENTROPY_NV_SEED */ + +#endif /* MBEDTLS_ENTROPY_C */ |