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-rw-r--r--lib/mbedtls-2.27.0/library/entropy_poll.c291
1 files changed, 291 insertions, 0 deletions
diff --git a/lib/mbedtls-2.27.0/library/entropy_poll.c b/lib/mbedtls-2.27.0/library/entropy_poll.c
new file mode 100644
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--- /dev/null
+++ b/lib/mbedtls-2.27.0/library/entropy_poll.c
@@ -0,0 +1,291 @@
+/*
+ * Platform-specific and custom entropy polling functions
+ *
+ * Copyright The Mbed TLS Contributors
+ * 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.
+ */
+
+#if defined(__linux__) && !defined(_GNU_SOURCE)
+/* Ensure that syscall() is available even when compiling with -std=c99 */
+#define _GNU_SOURCE
+#endif
+
+#include "common.h"
+
+#include <string.h>
+
+#if defined(MBEDTLS_ENTROPY_C)
+
+#include "mbedtls/entropy.h"
+#include "mbedtls/entropy_poll.h"
+#include "mbedtls/error.h"
+
+#if defined(MBEDTLS_TIMING_C)
+#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) && !defined(__QNXNTO__) && \
+ !defined(__HAIKU__) && !defined(__midipix__)
+#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__)) || defined(__midipix__))
+#include <unistd.h>
+#include <sys/syscall.h>
+#if defined(SYS_getrandom)
+#define HAVE_GETRANDOM
+#include <errno.h>
+
+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 ) );
+}
+#endif /* SYS_getrandom */
+#endif /* __linux__ || __midipix__ */
+
+#if defined(__FreeBSD__) || defined(__DragonFly__)
+#include <sys/param.h>
+#if (defined(__FreeBSD__) && __FreeBSD_version >= 1200000) || \
+ (defined(__DragonFly__) && __DragonFly_version >= 500700)
+#include <errno.h>
+#include <sys/random.h>
+#define HAVE_GETRANDOM
+static int getrandom_wrapper( void *buf, size_t buflen, unsigned int flags )
+{
+ return getrandom( buf, buflen, flags );
+}
+#endif /* (__FreeBSD__ && __FreeBSD_version >= 1200000) ||
+ (__DragonFly__ && __DragonFly_version >= 500700) */
+#endif /* __FreeBSD__ || __DragonFly__ */
+
+/*
+ * Some BSD systems provide KERN_ARND.
+ * This is equivalent to reading from /dev/urandom, only it doesn't require an
+ * open file descriptor, and provides up to 256 bytes per call (basically the
+ * same as getentropy(), but with a longer history).
+ *
+ * Documentation: https://netbsd.gw.com/cgi-bin/man-cgi?sysctl+7
+ */
+#if (defined(__FreeBSD__) || defined(__NetBSD__)) && !defined(HAVE_GETRANDOM)
+#include <sys/param.h>
+#include <sys/sysctl.h>
+#if defined(KERN_ARND)
+#define HAVE_SYSCTL_ARND
+
+static int sysctl_arnd_wrapper( unsigned char *buf, size_t buflen )
+{
+ int name[2];
+ size_t len;
+
+ name[0] = CTL_KERN;
+ name[1] = KERN_ARND;
+
+ while( buflen > 0 )
+ {
+ len = buflen > 256 ? 256 : buflen;
+ if( sysctl(name, 2, buf, &len, NULL, 0) == -1 )
+ return( -1 );
+ buflen -= len;
+ buf += len;
+ }
+ return( 0 );
+}
+#endif /* KERN_ARND */
+#endif /* __FreeBSD__ || __NetBSD__ */
+
+#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;
+ int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
+ ((void) data);
+
+#if defined(HAVE_GETRANDOM)
+ ret = getrandom_wrapper( output, len, 0 );
+ if( ret >= 0 )
+ {
+ *olen = ret;
+ return( 0 );
+ }
+ else if( errno != ENOSYS )
+ return( MBEDTLS_ERR_ENTROPY_SOURCE_FAILED );
+ /* Fall through if the system call isn't known. */
+#else
+ ((void) ret);
+#endif /* HAVE_GETRANDOM */
+
+#if defined(HAVE_SYSCTL_ARND)
+ ((void) file);
+ ((void) read_len);
+ if( sysctl_arnd_wrapper( output, len ) == -1 )
+ return( MBEDTLS_ERR_ENTROPY_SOURCE_FAILED );
+ *olen = len;
+ return( 0 );
+#else
+
+ *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 /* HAVE_SYSCTL_ARND */
+}
+#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 );
+
+ output[0] = 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 */