64 lines
2.0 KiB
C
64 lines
2.0 KiB
C
/* Hurdish implementation of getrandom
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Copyright (C) 2016-2021 Free Software Foundation, Inc.
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This file is part of the GNU C Library.
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The GNU C Library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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License as published by the Free Software Foundation; either
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version 2.1 of the License, or (at your option) any later version.
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The GNU C Library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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License along with the GNU C Library; if not, see
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<https://www.gnu.org/licenses/>. */
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#include <sys/random.h>
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#include <fcntl.h>
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#include <unistd.h>
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#include <not-cancel.h>
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extern char *__trivfs_server_name __attribute__((weak));
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/* Write up to LENGTH bytes of randomness starting at BUFFER.
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Return the number of bytes written, or -1 on error. */
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ssize_t
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__getrandom (void *buffer, size_t length, unsigned int flags)
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{
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const char *random_source = "/dev/urandom";
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int open_flags = O_RDONLY | O_CLOEXEC;
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size_t amount_read;
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int fd;
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if (&__trivfs_server_name && __trivfs_server_name
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&& __trivfs_server_name[0] == 'r'
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&& __trivfs_server_name[1] == 'a'
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&& __trivfs_server_name[2] == 'n'
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&& __trivfs_server_name[3] == 'd'
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&& __trivfs_server_name[4] == 'o'
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&& __trivfs_server_name[5] == 'm'
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&& __trivfs_server_name[6] == '\0')
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/* We are random, don't try to read ourselves! */
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return length;
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if (flags & GRND_RANDOM)
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random_source = "/dev/random";
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if (flags & GRND_NONBLOCK)
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open_flags |= O_NONBLOCK;
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fd = __open_nocancel(random_source, open_flags);
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if (fd == -1)
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return -1;
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amount_read = __read_nocancel(fd, buffer, length);
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__close_nocancel_nostatus(fd);
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return amount_read;
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}
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libc_hidden_def (__getrandom)
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weak_alias (__getrandom, getrandom)
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