1
mirror of https://github.com/jedisct1/libsodium.git synced 2024-12-20 02:25:14 -07:00
This commit is contained in:
Frank Denis 2017-01-19 21:27:28 +01:00
commit 3965574d3b
15 changed files with 458 additions and 479 deletions

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@ -1,7 +1,7 @@
/*
* ISC License
*
* Copyright (c) 2013-2016
* Copyright (c) 2013-2017
* Frank Denis <j at pureftpd dot org>
*
* Permission to use, copy, modify, and/or distribute this software for any

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@ -21,7 +21,7 @@ if [ ! -x "`which automake 2>/dev/null`" ] ; then
exit 1
fi
if [ -x "`which autoreconf 2>/dev/null`" ] ; then
if autoreconf --version > /dev/null 2>&1 ; then
exec autoreconf -ivf
fi

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@ -36,6 +36,7 @@ AC_SUBST(SODIUM_LIBRARY_VERSION_MINOR)
AC_SUBST(SODIUM_LIBRARY_VERSION)
AC_SUBST(DLL_VERSION)
AC_LANG_ASSERT(C)
LX_CFLAGS=${CFLAGS-NONE}
dnl Path check
@ -180,19 +181,14 @@ AX_CHECK_COMPILE_FLAG([-fvisibility=hidden],
[CFLAGS="$CFLAGS -fvisibility=hidden"])
AS_CASE([$host_os], [cygwin*|mingw*|msys|pw32*|cegcc*], [ ], [
AX_CHECK_COMPILE_FLAG([-fPIC], [
AX_CHECK_LINK_FLAG([-fPIC],
[CFLAGS="$CFLAGS -fPIC"]
)
])
AX_CHECK_COMPILE_FLAG([-fPIC], [CFLAGS="$CFLAGS -fPIC"])
])
AS_IF([test "$enable_pie" != "no"],[
AX_CHECK_COMPILE_FLAG([-fPIE], [
AX_CHECK_LINK_FLAG([-fPIE],
[AX_CHECK_LINK_FLAG([-pie],
AX_CHECK_LINK_FLAG([-pie], [
[CFLAGS="$CFLAGS -fPIE"
LDFLAGS="$LDFLAGS -pie"])
LDFLAGS="$LDFLAGS -pie"]
])
])
])

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@ -104,18 +104,14 @@ elseif (WIN32)
message(FATAL_ERROR "the ${_TARGET_ARCH} architecture is not supported by Findsodium.cmake.")
endif()
string(APPEND _PLATFORM_PATH "/$$CONFIG$$")
# this will need to be maintained manually -.-'
if (MSVC_VERSION EQUAL 1600)
string(APPEND _PLATFORM_PATH "/v100")
elseif (MSVC_VERSION EQUAL 1700)
string(APPEND _PLATFORM_PATH "/v110")
elseif (MSVC_VERSION EQUAL 1800)
string(APPEND _PLATFORM_PATH "/v120")
elseif (MSVC_VERSION EQUAL 1900)
string(APPEND _PLATFORM_PATH "/v140")
if (MSVC_VERSION LESS 1900)
math(EXPR _VS_VERSION "${MSVC_VERSION} / 10 - 60")
else()
message(FATAL_ERROR "msvc version ${MSVC_VERSION} is not supported by Findsodium.cmake.")
math(EXPR _VS_VERSION "${MSVC_VERSION} / 10 - 50")
endif()
string(APPEND _PLATFORM_PATH "/v${_VS_VERSION}")
if (sodium_USE_STATIC_LIBS)
string(APPEND _PLATFORM_PATH "/static")
else()

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@ -1,3 +1,3 @@
EXTRA_DIST = \
FindSodium.cmake
Findsodium.cmake

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@ -53,7 +53,7 @@
# modified version of the Autoconf Macro, you may extend this special
# exception to the GPL to apply to your modified version as well.
#serial 2
#serial 4
AC_DEFUN([AX_CHECK_COMPILE_FLAG],
[AC_PREREQ(2.64)dnl for _AC_LANG_PREFIX and AS_VAR_IF
@ -61,8 +61,8 @@ AS_VAR_PUSHDEF([CACHEVAR],[ax_cv_check_[]_AC_LANG_ABBREV[]flags_$4_$1])dnl
AC_CACHE_CHECK([whether _AC_LANG compiler accepts $1], CACHEVAR, [
ax_check_save_flags=$[]_AC_LANG_PREFIX[]FLAGS
_AC_LANG_PREFIX[]FLAGS="$[]_AC_LANG_PREFIX[]FLAGS $4 $1"
AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#include <stdio.h>]],
[[char x[42U], fodder = 0;if (fodder > -1000 && fgets(x,1000,stdin)) puts(x)]])],
AC_TRY_LINK([#include <stdio.h>],
[char x[42U], fodder = 0;if (fodder > -1000 && fgets(x,1000,stdin)) puts(x)],
[AS_VAR_SET(CACHEVAR,[yes])],
[AS_VAR_SET(CACHEVAR,[no])])
_AC_LANG_PREFIX[]FLAGS=$ax_check_save_flags])

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@ -8,12 +8,18 @@
#
# DESCRIPTION
#
# This macro searches for a GNU version of make. If a match is found, the
# makefile variable `ifGNUmake' is set to the empty string, otherwise it
# is set to "#". This is useful for including a special features in a
# Makefile, which cannot be handled by other versions of make. The
# variable _cv_gnu_make_command is set to the command to invoke GNU make
# if it exists, the empty string otherwise.
# This macro searches for a GNU version of make. If a match is found:
#
# * The makefile variable `ifGNUmake' is set to the empty string, otherwise
# it is set to "#". This is useful for including a special features in a
# Makefile, which cannot be handled by other versions of make.
# * The variable `_cv_gnu_make_command` is set to the command to invoke
# GNU make if it exists, the empty string otherwise.
# * The variable `ax_cv_gnu_make_command` is set to the command to invoke
# GNU make by copying `_cv_gnu_make_command`, otherwise it is unset.
# * If GNU Make is found, its version is extracted from the output of
# `make --version` as the last field of a record of space-separated
# columns and saved into the variable `ax_check_gnu_make_version`.
#
# Here is an example of its use:
#
@ -48,31 +54,31 @@
# LICENSE
#
# Copyright (c) 2008 John Darrington <j.darrington@elvis.murdoch.edu.au>
# Copyright (c) 2015 Enrico M. Crisostomo <enrico.m.crisostomo@gmail.com>
#
# Copying and distribution of this file, with or without modification, are
# permitted in any medium without royalty provided the copyright notice
# and this notice are preserved. This file is offered as-is, without any
# warranty.
#serial 7
#serial 8
AC_DEFUN([AX_CHECK_GNU_MAKE], [ AC_CACHE_CHECK( for GNU make,_cv_gnu_make_command,
_cv_gnu_make_command='' ;
AC_DEFUN([AX_CHECK_GNU_MAKE],dnl
[AC_PROG_AWK
AC_CACHE_CHECK([for GNU make],[_cv_gnu_make_command],[dnl
_cv_gnu_make_command="" ;
dnl Search all the common names for GNU make
for a in "$MAKE" make gmake gnumake ; do
if test -z "$a" ; then continue ; fi ;
if ( sh -c "$a --version" 2> /dev/null | grep GNU 2>&1 > /dev/null ) ; then
if "$a" --version 2> /dev/null | grep GNU 2>&1 > /dev/null ; then
_cv_gnu_make_command=$a ;
break;
AX_CHECK_GNU_MAKE_HEADLINE=$("$a" --version 2> /dev/null | grep "GNU Make")
ax_check_gnu_make_version=$(echo ${AX_CHECK_GNU_MAKE_HEADLINE} | ${AWK} -F " " '{ print $(NF); }')
break ;
fi
done ;
) ;
done ;])
dnl If there was a GNU version, then set @ifGNUmake@ to the empty string, '#' otherwise
if test "x$_cv_gnu_make_command" != "x" ; then
ifGNUmake='' ;
else
ifGNUmake='#' ;
AC_MSG_RESULT("Not found");
fi
AC_SUBST(ifGNUmake)
] )
AS_VAR_IF([_cv_gnu_make_command], [""], [AS_VAR_SET([ifGNUmake], ["#"])], [AS_VAR_SET([ifGNUmake], [""])])
AS_VAR_IF([_cv_gnu_make_command], [""], [AS_UNSET(ax_cv_gnu_make_command)], [AS_VAR_SET([ax_cv_gnu_make_command], [${_cv_gnu_make_command}])])
AC_SUBST([ifGNUmake])
])

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@ -53,7 +53,7 @@
# modified version of the Autoconf Macro, you may extend this special
# exception to the GPL to apply to your modified version as well.
#serial 2
#serial 4
AC_DEFUN([AX_CHECK_LINK_FLAG],
[AC_PREREQ(2.64)dnl for _AC_LANG_PREFIX and AS_VAR_IF

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@ -82,7 +82,7 @@
# modified version of the Autoconf Macro, you may extend this special
# exception to the GPL to apply to your modified version as well.
#serial 22
#serial 23
AU_ALIAS([ACX_PTHREAD], [AX_PTHREAD])
AC_DEFUN([AX_PTHREAD], [
@ -212,7 +212,7 @@ case $host_os in
ax_pthread_check_macro="_REENTRANT"
;;
aix* | freebsd*)
aix*)
ax_pthread_check_macro="_THREAD_SAFE"
;;

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@ -3,7 +3,6 @@ lib_LTLIBRARIES = \
libsodium_la_SOURCES = \
crypto_aead/chacha20poly1305/sodium/aead_chacha20poly1305.c \
crypto_aead/xchacha20poly1305/sodium/aead_xchacha20poly1305.c \
crypto_auth/crypto_auth.c \
crypto_auth/hmacsha256/auth_hmacsha256_api.c \
crypto_auth/hmacsha256/cp/hmac_hmacsha256.c \
@ -170,6 +169,7 @@ endif
if !MINIMAL
libsodium_la_SOURCES += \
crypto_aead/xchacha20poly1305/sodium/aead_xchacha20poly1305.c \
crypto_box/curve25519xchacha20poly1305/box_curve25519xchacha20poly1305_api.c \
crypto_box/curve25519xchacha20poly1305/box_curve25519xchacha20poly1305_easy.c \
crypto_box/curve25519xchacha20poly1305/sodium/after_curve25519xchacha20poly1305.c \

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@ -5,15 +5,14 @@
#include <string.h>
#include "crypto_aead_xchacha20poly1305.h"
#include "crypto_onetimeauth_poly1305.h"
#include "crypto_stream_xchacha20.h"
#include "crypto_verify_16.h"
#include "crypto_aead_chacha20poly1305.h"
#include "crypto_core_hchacha20.h"
#include "utils.h"
#include "private/common.h"
int
crypto_aead_xchacha20poly1305_encrypt_detached(unsigned char *c,
crypto_aead_xchacha20poly1305_ietf_encrypt_detached(unsigned char *c,
unsigned char *mac,
unsigned long long *maclen_p,
const unsigned char *m,
@ -24,36 +23,22 @@ crypto_aead_xchacha20poly1305_encrypt_detached(unsigned char *c,
const unsigned char *npub,
const unsigned char *k)
{
crypto_onetimeauth_poly1305_state state;
unsigned char block0[64U];
unsigned char slen[8U];
unsigned char k2[crypto_core_hchacha20_OUTPUTBYTES];
unsigned char npub2[crypto_aead_chacha20poly1305_ietf_NPUBBYTES] = { 0 };
int ret;
(void) nsec;
crypto_stream_xchacha20(block0, sizeof block0, npub, k);
crypto_onetimeauth_poly1305_init(&state, block0);
sodium_memzero(block0, sizeof block0);
crypto_core_hchacha20(k2, npub, k, NULL);
memcpy(npub2 + 4, npub + crypto_core_hchacha20_INPUTBYTES,
crypto_aead_chacha20poly1305_ietf_NPUBBYTES - 4);
ret = crypto_aead_chacha20poly1305_ietf_encrypt_detached
(c, mac, maclen_p, m, mlen, ad, adlen, nsec, npub2, k2);
sodium_memzero(k2, crypto_core_hchacha20_OUTPUTBYTES);
crypto_onetimeauth_poly1305_update(&state, ad, adlen);
STORE64_LE(slen, (uint64_t) adlen);
crypto_onetimeauth_poly1305_update(&state, slen, sizeof slen);
crypto_stream_xchacha20_xor_ic(c, m, mlen, npub, 1U, k);
crypto_onetimeauth_poly1305_update(&state, c, mlen);
STORE64_LE(slen, (uint64_t) mlen);
crypto_onetimeauth_poly1305_update(&state, slen, sizeof slen);
crypto_onetimeauth_poly1305_final(&state, mac);
sodium_memzero(&state, sizeof state);
if (maclen_p != NULL) {
*maclen_p = crypto_aead_xchacha20poly1305_ABYTES;
}
return 0;
return ret;
}
int
crypto_aead_xchacha20poly1305_encrypt(unsigned char *c,
crypto_aead_xchacha20poly1305_ietf_encrypt(unsigned char *c,
unsigned long long *clen_p,
const unsigned char *m,
unsigned long long mlen,
@ -66,17 +51,14 @@ crypto_aead_xchacha20poly1305_encrypt(unsigned char *c,
unsigned long long clen = 0ULL;
int ret;
if (mlen > UINT64_MAX - crypto_aead_xchacha20poly1305_ABYTES) {
if (mlen > UINT64_MAX - crypto_aead_xchacha20poly1305_ietf_ABYTES) {
abort(); /* LCOV_EXCL_LINE */
}
ret = crypto_aead_xchacha20poly1305_encrypt_detached(c,
c + mlen, NULL,
m, mlen,
ad, adlen,
nsec, npub, k);
ret = crypto_aead_xchacha20poly1305_ietf_encrypt_detached
(c, c + mlen, NULL, m, mlen, ad, adlen, nsec, npub, k);
if (clen_p != NULL) {
if (ret == 0) {
clen = mlen + crypto_aead_xchacha20poly1305_ABYTES;
clen = mlen + crypto_aead_xchacha20poly1305_ietf_ABYTES;
}
*clen_p = clen;
}
@ -84,7 +66,7 @@ crypto_aead_xchacha20poly1305_encrypt(unsigned char *c,
}
int
crypto_aead_xchacha20poly1305_decrypt_detached(unsigned char *m,
crypto_aead_xchacha20poly1305_ietf_decrypt_detached(unsigned char *m,
unsigned char *nsec,
const unsigned char *c,
unsigned long long clen,
@ -94,47 +76,23 @@ crypto_aead_xchacha20poly1305_decrypt_detached(unsigned char *m,
const unsigned char *npub,
const unsigned char *k)
{
crypto_onetimeauth_poly1305_state state;
unsigned char block0[64U];
unsigned char slen[8U];
unsigned char computed_mac[crypto_aead_xchacha20poly1305_ABYTES];
unsigned long long mlen;
unsigned char k2[crypto_core_hchacha20_OUTPUTBYTES];
unsigned char npub2[crypto_aead_chacha20poly1305_ietf_NPUBBYTES] = { 0 };
int ret;
(void) nsec;
crypto_stream_xchacha20(block0, sizeof block0, npub, k);
crypto_onetimeauth_poly1305_init(&state, block0);
sodium_memzero(block0, sizeof block0);
crypto_core_hchacha20(k2, npub, k, NULL);
memcpy(npub2 + 4, npub + crypto_core_hchacha20_INPUTBYTES,
crypto_aead_chacha20poly1305_ietf_NPUBBYTES - 4);
ret = crypto_aead_chacha20poly1305_ietf_decrypt_detached
(m, nsec, c, clen, mac, ad, adlen, npub2, k2);
sodium_memzero(k2, crypto_core_hchacha20_OUTPUTBYTES);
crypto_onetimeauth_poly1305_update(&state, ad, adlen);
STORE64_LE(slen, (uint64_t) adlen);
crypto_onetimeauth_poly1305_update(&state, slen, sizeof slen);
mlen = clen;
crypto_onetimeauth_poly1305_update(&state, c, mlen);
STORE64_LE(slen, (uint64_t) mlen);
crypto_onetimeauth_poly1305_update(&state, slen, sizeof slen);
crypto_onetimeauth_poly1305_final(&state, computed_mac);
sodium_memzero(&state, sizeof state);
(void) sizeof(int[sizeof computed_mac == 16U ? 1 : -1]);
ret = crypto_verify_16(computed_mac, mac);
sodium_memzero(computed_mac, sizeof computed_mac);
if (m == NULL) {
return ret;
}
if (ret != 0) {
memset(m, 0, mlen);
return -1;
}
crypto_stream_xchacha20_xor_ic(m, c, mlen, npub, 1U, k);
return 0;
}
int
crypto_aead_xchacha20poly1305_decrypt(unsigned char *m,
crypto_aead_xchacha20poly1305_ietf_decrypt(unsigned char *m,
unsigned long long *mlen_p,
unsigned char *nsec,
const unsigned char *c,
@ -147,16 +105,16 @@ crypto_aead_xchacha20poly1305_decrypt(unsigned char *m,
unsigned long long mlen = 0ULL;
int ret = -1;
if (clen >= crypto_aead_xchacha20poly1305_ABYTES) {
ret = crypto_aead_xchacha20poly1305_decrypt_detached
if (clen >= crypto_aead_xchacha20poly1305_ietf_ABYTES) {
ret = crypto_aead_xchacha20poly1305_ietf_decrypt_detached
(m, nsec,
c, clen - crypto_aead_xchacha20poly1305_ABYTES,
c + clen - crypto_aead_xchacha20poly1305_ABYTES,
c, clen - crypto_aead_xchacha20poly1305_ietf_ABYTES,
c + clen - crypto_aead_xchacha20poly1305_ietf_ABYTES,
ad, adlen, npub, k);
}
if (mlen_p != NULL) {
if (ret == 0) {
mlen = clen - crypto_aead_xchacha20poly1305_ABYTES;
mlen = clen - crypto_aead_xchacha20poly1305_ietf_ABYTES;
}
*mlen_p = mlen;
}
@ -164,21 +122,21 @@ crypto_aead_xchacha20poly1305_decrypt(unsigned char *m,
}
size_t
crypto_aead_xchacha20poly1305_keybytes(void) {
return crypto_aead_xchacha20poly1305_KEYBYTES;
crypto_aead_xchacha20poly1305_ietf_keybytes(void) {
return crypto_aead_xchacha20poly1305_ietf_KEYBYTES;
}
size_t
crypto_aead_xchacha20poly1305_npubbytes(void) {
return crypto_aead_xchacha20poly1305_NPUBBYTES;
crypto_aead_xchacha20poly1305_ietf_npubbytes(void) {
return crypto_aead_xchacha20poly1305_ietf_NPUBBYTES;
}
size_t
crypto_aead_xchacha20poly1305_nsecbytes(void) {
return crypto_aead_xchacha20poly1305_NSECBYTES;
crypto_aead_xchacha20poly1305_ietf_nsecbytes(void) {
return crypto_aead_xchacha20poly1305_ietf_NSECBYTES;
}
size_t
crypto_aead_xchacha20poly1305_abytes(void) {
return crypto_aead_xchacha20poly1305_ABYTES;
crypto_aead_xchacha20poly1305_ietf_abytes(void) {
return crypto_aead_xchacha20poly1305_ietf_ABYTES;
}

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@ -11,24 +11,24 @@
extern "C" {
#endif
#define crypto_aead_xchacha20poly1305_KEYBYTES 32U
#define crypto_aead_xchacha20poly1305_ietf_KEYBYTES 32U
SODIUM_EXPORT
size_t crypto_aead_xchacha20poly1305_keybytes(void);
size_t crypto_aead_xchacha20poly1305_ietf_keybytes(void);
#define crypto_aead_xchacha20poly1305_NSECBYTES 0U
#define crypto_aead_xchacha20poly1305_ietf_NSECBYTES 0U
SODIUM_EXPORT
size_t crypto_aead_xchacha20poly1305_nsecbytes(void);
size_t crypto_aead_xchacha20poly1305_ietf_nsecbytes(void);
#define crypto_aead_xchacha20poly1305_NPUBBYTES 24U
#define crypto_aead_xchacha20poly1305_ietf_NPUBBYTES 24U
SODIUM_EXPORT
size_t crypto_aead_xchacha20poly1305_npubbytes(void);
size_t crypto_aead_xchacha20poly1305_ietf_npubbytes(void);
#define crypto_aead_xchacha20poly1305_ABYTES 16U
#define crypto_aead_xchacha20poly1305_ietf_ABYTES 16U
SODIUM_EXPORT
size_t crypto_aead_xchacha20poly1305_abytes(void);
size_t crypto_aead_xchacha20poly1305_ietf_abytes(void);
SODIUM_EXPORT
int crypto_aead_xchacha20poly1305_encrypt(unsigned char *c,
int crypto_aead_xchacha20poly1305_ietf_encrypt(unsigned char *c,
unsigned long long *clen_p,
const unsigned char *m,
unsigned long long mlen,
@ -39,7 +39,7 @@ int crypto_aead_xchacha20poly1305_encrypt(unsigned char *c,
const unsigned char *k);
SODIUM_EXPORT
int crypto_aead_xchacha20poly1305_decrypt(unsigned char *m,
int crypto_aead_xchacha20poly1305_ietf_decrypt(unsigned char *m,
unsigned long long *mlen_p,
unsigned char *nsec,
const unsigned char *c,
@ -51,7 +51,7 @@ int crypto_aead_xchacha20poly1305_decrypt(unsigned char *m,
__attribute__ ((warn_unused_result));
SODIUM_EXPORT
int crypto_aead_xchacha20poly1305_encrypt_detached(unsigned char *c,
int crypto_aead_xchacha20poly1305_ietf_encrypt_detached(unsigned char *c,
unsigned char *mac,
unsigned long long *maclen_p,
const unsigned char *m,
@ -63,7 +63,7 @@ int crypto_aead_xchacha20poly1305_encrypt_detached(unsigned char *c,
const unsigned char *k);
SODIUM_EXPORT
int crypto_aead_xchacha20poly1305_decrypt_detached(unsigned char *m,
int crypto_aead_xchacha20poly1305_ietf_decrypt_detached(unsigned char *m,
unsigned char *nsec,
const unsigned char *c,
unsigned long long clen,
@ -74,6 +74,13 @@ int crypto_aead_xchacha20poly1305_decrypt_detached(unsigned char *m,
const unsigned char *k)
__attribute__ ((warn_unused_result));
/* Aliases */
#define crypto_aead_xchacha20poly1305_IETF_KEYBYTES crypto_aead_xchacha20poly1305_ietf_KEYBYTES
#define crypto_aead_xchacha20poly1305_IETF_NSECBYTES crypto_aead_xchacha20poly1305_ietf_NSECBYTES
#define crypto_aead_xchacha20poly1305_IETF_NPUBBYTES crypto_aead_xchacha20poly1305_ietf_NPUBBYTES
#define crypto_aead_xchacha20poly1305_IETF_ABYTES crypto_aead_xchacha20poly1305_ietf_ABYTES
#ifdef __cplusplus
}
#endif

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@ -6,7 +6,11 @@
# include <sys/time.h>
#endif
#ifdef __linux__
# ifdef __dietlibc__
# define _LINUX_SOURCE
# else
# include <sys/syscall.h>
# endif
# include <poll.h>
#endif
@ -207,7 +211,7 @@ randombytes_salsa20_random_random_dev_open(void)
}
# endif
# if defined(SYS_getrandom) && defined(__NR_getrandom)
# if defined(__dietlibc__) || (defined(SYS_getrandom) && defined(__NR_getrandom))
static int
_randombytes_linux_getrandom(void * const buf, const size_t size)
{
@ -215,7 +219,11 @@ _randombytes_linux_getrandom(void * const buf, const size_t size)
assert(size <= 256U);
do {
# ifdef __dietlibc__
readnb = getrandom(buf, size, 0);
# else
readnb = syscall(SYS_getrandom, buf, (int) size, 0);
# endif
} while (readnb < 0 && (errno == EINTR || errno == EAGAIN));
return (readnb == (int) size) - 1;

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@ -6,7 +6,11 @@
# include <sys/time.h>
#endif
#ifdef __linux__
# ifdef __dietlibc__
# define _LINUX_SOURCE
# else
# include <sys/syscall.h>
# endif
# include <poll.h>
#endif
@ -189,7 +193,7 @@ randombytes_sysrandom_random_dev_open(void)
/* LCOV_EXCL_STOP */
}
# if defined(SYS_getrandom) && defined(__NR_getrandom)
# if defined(__dietlibc__) || (defined(SYS_getrandom) && defined(__NR_getrandom))
static int
_randombytes_linux_getrandom(void * const buf, const size_t size)
{
@ -197,7 +201,11 @@ _randombytes_linux_getrandom(void * const buf, const size_t size)
assert(size <= 256U);
do {
# ifdef __dietlibc__
readnb = getrandom(buf, size, 0);
# else
readnb = syscall(SYS_getrandom, buf, (int) size, 0);
# endif
} while (readnb < 0 && (errno == EINTR || errno == EAGAIN));
return (readnb == (int) size) - 1;