First commit

Signed-off-by: Mattias Andrée <m@maandree.se>

1 files changed, 142 insertions, 0 deletions

diff --git a/librecrypt_fill_with_random_.c b/librecrypt_fill_with_random_.c
new file mode 100644
index 0000000..475a156
--- /dev/null
+++ b/librecrypt_fill_with_random_.c
@@ -0,0 +1,142 @@
+/* See LICENSE file for copyright and license details. */
+#include "common.h"
+#ifndef TEST
+
+
+int
+librecrypt_fill_with_random_(void *out, size_t n, ssize_t (*rng)(void *out, size_t n, void *user), void *user)
+{
+	char *buf = out;
+	ssize_t r;
+
+	if (!rng)
+		rng = &librecrypt_rng_;
+
+	while (n) {
+		r = (*rng)(buf, n, user);
+		if (r <= 0) {
+			if (!r)
+				abort();
+			return -1;
+		}
+		buf = &buf[(size_t)r];
+		n -= (size_t)r;
+	}
+
+	return 0;
+}
+
+
+#else
+
+
+static ssize_t
+zero(void *out, size_t n, void *user)
+{
+	(void) user;
+	memset(out, 0, n);
+	return (ssize_t)n;
+}
+
+
+static ssize_t
+seq(void *out, size_t n, void *user)
+{
+	unsigned char *restrict buf = out;
+	unsigned char *restrict num = user;
+	size_t i;
+	if (n > 64u)
+		n = 64u;
+	for (i = 0u; i < n; i++)
+		buf[i] = (*num)++;
+	return (ssize_t)n;
+}
+
+
+static ssize_t
+next(void *out, size_t n, void *user)
+{
+	unsigned char *restrict buf = out;
+	unsigned char *restrict num = user;
+	assert(n);
+	*buf = (*num)++;
+	return 1;
+}
+
+
+static ssize_t
+failer(void *out, size_t n, void *user)
+{
+	(void) out;
+	(void) n;
+	(void) user;
+	errno = EDOM;
+	return -1;
+}
+
+
+static ssize_t
+zero_ret(void *out, size_t n, void *user)
+{
+	(void) out;
+	(void) n;
+	(void) user;
+	return 0;
+}
+
+
+int
+main(void)
+{
+	unsigned char buf1[1024u];
+	unsigned char buf2[sizeof(buf1)];
+	unsigned char s;
+	size_t i;
+	int rv = 0;
+
+	INIT_TEST_ABORT();
+
+	SET_UP_ALARM();
+
+	EXPECT(librecrypt_fill_with_random_(buf1, sizeof(buf1), NULL, NULL) == 0);
+	EXPECT(librecrypt_fill_with_random_(buf2, sizeof(buf1), NULL, NULL) == 0);
+	EXPECT(memcmp(buf1, buf2, sizeof(buf1)));
+
+	memset(buf1, 99, sizeof(buf1));
+	errno = 0;
+	EXPECT(librecrypt_fill_with_random_(buf1, sizeof(buf1), &zero, NULL) == 0);
+	EXPECT(errno == 0);
+	for (s = 0u, i = 0u; i < sizeof(buf1); i++, s++)
+		EXPECT(!buf1[i]);
+
+	memset(buf1, 99, sizeof(buf1));
+	s = 0u;
+	errno = 0;
+	EXPECT(librecrypt_fill_with_random_(buf1, sizeof(buf1), &seq, &s) == 0);
+	EXPECT(errno == 0);
+	for (s = 0u, i = 0u; i < sizeof(buf1); i++, s++)
+		EXPECT(buf1[i] == s);
+
+	memset(buf1, 99, sizeof(buf1));
+	s = 0u;
+	errno = 0;
+	EXPECT(librecrypt_fill_with_random_(buf1, sizeof(buf1), &next, &s) == 0);
+	EXPECT(errno == 0);
+	for (s = 0u, i = 0u; i < sizeof(buf1); i++, s++)
+		EXPECT(buf1[i] == s);
+
+	memset(buf1, 99, sizeof(buf1));
+	s = 0u;
+	errno = 0;
+	EXPECT(librecrypt_fill_with_random_(buf1, sizeof(buf1), &failer, NULL) == -1);
+	EXPECT(errno == EDOM);
+	for (s = 0u, i = 0u; i < sizeof(buf1); i++, s++)
+		EXPECT(buf1[i] == 99);
+
+	EXPECT_ABORT(rv = librecrypt_fill_with_random_(buf1, sizeof(buf1), &zero_ret, NULL));
+
+	return rv;
+}
+
+
+#endif