8 files changed, 216 insertions, 0 deletions
diff --git a/v_windows/v/old/vlib/crypto/rand/crypto_rand_read_test.v b/v_windows/v/old/vlib/crypto/rand/crypto_rand_read_test.v
new file mode 100644
index 0000000..824923d
--- /dev/null
+++ b/v_windows/v/old/vlib/crypto/rand/crypto_rand_read_test.v
@@ -0,0 +1,15 @@
+import crypto.rand
+
+fn test_reading() ? {
+	a := rand.read(32) ?
+	// dump(a.hex())
+	assert a.len == 32
+	mut histogram := [256]int{}
+	for b in a {
+		histogram[b]++
+	}
+	// dump(histogram)
+	for h in histogram {
+		assert h < 10
+	}
+}
diff --git a/v_windows/v/old/vlib/crypto/rand/rand.v b/v_windows/v/old/vlib/crypto/rand/rand.v
new file mode 100644
index 0000000..0703558
--- /dev/null
+++ b/v_windows/v/old/vlib/crypto/rand/rand.v
@@ -0,0 +1,10 @@
+// Copyright (c) 2019-2021 Alexander Medvednikov. All rights reserved.
+// Use of this source code is governed by an MIT license
+// that can be found in the LICENSE file.
+
+module rand
+
+struct ReadError {
+	msg  string = 'crypto.rand.read() error reading random bytes'
+	code int
+}
diff --git a/v_windows/v/old/vlib/crypto/rand/rand_darwin.c.v b/v_windows/v/old/vlib/crypto/rand/rand_darwin.c.v
new file mode 100644
index 0000000..a53198b
--- /dev/null
+++ b/v_windows/v/old/vlib/crypto/rand/rand_darwin.c.v
@@ -0,0 +1,21 @@
+// Copyright (c) 2019-2021 Alexander Medvednikov. All rights reserved.
+// Use of this source code is governed by an MIT license
+// that can be found in the LICENSE file.
+
+module rand
+
+#include <Security/SecRandom.h>
+
+#flag darwin -framework Security
+
+fn C.SecRandomCopyBytes(rnd C.SecRandomRef, count size_t, bytes voidptr) int
+
+// read returns an array of `bytes_needed` random bytes read from the OS.
+pub fn read(bytes_needed int) ?[]byte {
+	mut buffer := []byte{len: bytes_needed}
+	status := C.SecRandomCopyBytes(C.SecRandomRef(0), bytes_needed, buffer.data)
+	if status != 0 {
+		return IError(&ReadError{})
+	}
+	return buffer
+}
diff --git a/v_windows/v/old/vlib/crypto/rand/rand_default.c.v b/v_windows/v/old/vlib/crypto/rand/rand_default.c.v
new file mode 100644
index 0000000..2e1e823
--- /dev/null
+++ b/v_windows/v/old/vlib/crypto/rand/rand_default.c.v
@@ -0,0 +1,9 @@
+// Copyright (c) 2019-2021 Alexander Medvednikov. All rights reserved.
+// Use of this source code is governed by an MIT license
+// that can be found in the LICENSE file.
+module rand
+
+// read returns an array of `bytes_needed` random bytes read from the OS.
+pub fn read(bytes_needed int) ?[]byte {
+	return error('rand.read is not implemented on this platform')
+}
diff --git a/v_windows/v/old/vlib/crypto/rand/rand_linux.c.v b/v_windows/v/old/vlib/crypto/rand/rand_linux.c.v
new file mode 100644
index 0000000..52ff3da
--- /dev/null
+++ b/v_windows/v/old/vlib/crypto/rand/rand_linux.c.v
@@ -0,0 +1,39 @@
+// Copyright (c) 2019-2021 Alexander Medvednikov. All rights reserved.
+// Use of this source code is governed by an MIT license
+// that can be found in the LICENSE file.
+module rand
+
+#include <sys/syscall.h>
+
+const (
+	read_batch_size = 256
+)
+
+// read returns an array of `bytes_needed` random bytes read from the OS.
+pub fn read(bytes_needed int) ?[]byte {
+	mut buffer := unsafe { malloc_noscan(bytes_needed) }
+	mut bytes_read := 0
+	mut remaining_bytes := bytes_needed
+	// getrandom syscall wont block if requesting <= 256 bytes
+	for bytes_read < bytes_needed {
+		batch_size := if remaining_bytes > rand.read_batch_size {
+			rand.read_batch_size
+		} else {
+			remaining_bytes
+		}
+		rbytes := unsafe { getrandom(batch_size, buffer + bytes_read) }
+		if rbytes == -1 {
+			unsafe { free(buffer) }
+			return IError(&ReadError{})
+		}
+		bytes_read += rbytes
+	}
+	return unsafe { buffer.vbytes(bytes_needed) }
+}
+
+fn getrandom(bytes_needed int, buffer voidptr) int {
+	if bytes_needed > rand.read_batch_size {
+		panic('getrandom() dont request more than $rand.read_batch_size bytes at once.')
+	}
+	return unsafe { C.syscall(C.SYS_getrandom, buffer, bytes_needed, 0) }
+}
diff --git a/v_windows/v/old/vlib/crypto/rand/rand_solaris.c.v b/v_windows/v/old/vlib/crypto/rand/rand_solaris.c.v
new file mode 100644
index 0000000..8d0ba0c
--- /dev/null
+++ b/v_windows/v/old/vlib/crypto/rand/rand_solaris.c.v
@@ -0,0 +1,42 @@
+// Copyright (c) 2019-2021 Alexander Medvednikov. All rights reserved.
+// Use of this source code is governed by an MIT license
+// that can be found in the LICENSE file.
+
+module rand
+
+#include <sys/random.h>
+
+fn C.getrandom(p &byte, n size_t, flags u32) int
+
+const (
+	read_batch_size = 256
+)
+
+// read returns an array of `bytes_needed` random bytes read from the OS.
+pub fn read(bytes_needed int) ?[]byte {
+	mut buffer := unsafe { malloc_noscan(bytes_needed) }
+	mut bytes_read := 0
+	mut remaining_bytes := bytes_needed
+	// getrandom syscall wont block if requesting <= 256 bytes
+	for bytes_read < bytes_needed {
+		batch_size := if remaining_bytes > rand.read_batch_size {
+			rand.read_batch_size
+		} else {
+			remaining_bytes
+		}
+		rbytes := unsafe { getrandom(batch_size, buffer + bytes_read) }
+		if rbytes == -1 {
+			unsafe { free(buffer) }
+			return IError(&ReadError{})
+		}
+		bytes_read += rbytes
+	}
+	return unsafe { buffer.vbytes(bytes_needed) }
+}
+
+fn v_getrandom(bytes_needed int, buffer voidptr) int {
+	if bytes_needed > rand.read_batch_size {
+		panic('getrandom() dont request more than $rand.read_batch_size bytes at once.')
+	}
+	return C.getrandom(buffer, bytes_needed, 0)
+}
diff --git a/v_windows/v/old/vlib/crypto/rand/rand_windows.c.v b/v_windows/v/old/vlib/crypto/rand/rand_windows.c.v
new file mode 100644
index 0000000..075a3ed
--- /dev/null
+++ b/v_windows/v/old/vlib/crypto/rand/rand_windows.c.v
@@ -0,0 +1,25 @@
+// Copyright (c) 2019-2021 Alexander Medvednikov. All rights reserved.
+// Use of this source code is governed by an MIT license
+// that can be found in the LICENSE file.
+
+module rand
+
+#flag windows -Llibraries/bcrypt
+#flag windows -lbcrypt
+#include <bcrypt.h>
+
+const (
+	status_success                  = 0x00000000
+	bcrypt_use_system_preferred_rng = 0x00000002
+)
+
+// read returns an array of `bytes_needed` random bytes read from the OS.
+pub fn read(bytes_needed int) ?[]byte {
+	mut buffer := []byte{len: bytes_needed}
+	// use bcrypt_use_system_preferred_rng because we passed null as algo
+	status := C.BCryptGenRandom(0, buffer.data, bytes_needed, rand.bcrypt_use_system_preferred_rng)
+	if status != rand.status_success {
+		return IError(&ReadError{})
+	}
+	return buffer
+}
diff --git a/v_windows/v/old/vlib/crypto/rand/utils.v b/v_windows/v/old/vlib/crypto/rand/utils.v
new file mode 100644
index 0000000..31eaf2d
--- /dev/null
+++ b/v_windows/v/old/vlib/crypto/rand/utils.v
@@ -0,0 +1,55 @@
+// Copyright (c) 2019-2021 Alexander Medvednikov. All rights reserved.
+// Use of this source code is governed by an MIT license
+// that can be found in the LICENSE file.
+
+module rand
+
+import math.bits
+import encoding.binary
+
+// int_u64 returns a random unsigned 64-bit integer `u64` read from a real OS source of entropy.
+pub fn int_u64(max u64) ?u64 {
+	bitlen := bits.len_64(max)
+	if bitlen == 0 {
+		return u64(0)
+	}
+	k := (bitlen + 7) / 8
+	mut b := u64(bitlen % 8)
+	if b == u64(0) {
+		b = u64(8)
+	}
+	mut n := u64(0)
+	for {
+		mut bytes := read(k) ?
+		bytes[0] &= byte(int(u64(1) << b) - 1)
+		x := bytes_to_u64(bytes)
+		n = x[0]
+		// NOTE: maybe until we have bigint could do it another way?
+		// if x.len > 1 {
+		// 	n = u64(u32(x[1])<<u32(32)) | n
+		// }
+		if n < max {
+			return n
+		}
+	}
+	return n
+}
+
+fn bytes_to_u64(b []byte) []u64 {
+	ws := 64 / 8
+	mut z := []u64{len: ((b.len + ws - 1) / ws)}
+	mut i := b.len
+	for k := 0; i >= ws; k++ {
+		z[k] = binary.big_endian_u64(b[i - ws..i])
+		i -= ws
+	}
+	if i > 0 {
+		mut d := u64(0)
+		for s := u64(0); i > 0; s += u64(8) {
+			d |= u64(b[i - 1]) << s
+			i--
+		}
+		z[z.len - 1] = d
+	}
+	return z
+}