ASR_BASE

Change-Id: Icf3719cc0afe3eeb3edc7fa80a2eb5199ca9dda1
diff --git a/package/kernel/asr-wl/asr-hostapd/asr-hostapd-2023-06-22/src/crypto/random.c b/package/kernel/asr-wl/asr-hostapd/asr-hostapd-2023-06-22/src/crypto/random.c
new file mode 100644
index 0000000..548b60d
--- /dev/null
+++ b/package/kernel/asr-wl/asr-hostapd/asr-hostapd-2023-06-22/src/crypto/random.c
@@ -0,0 +1,478 @@
+/*
+ * Random number generator
+ * Copyright (c) 2010-2011, Jouni Malinen <j@w1.fi>
+ *
+ * This software may be distributed under the terms of the BSD license.
+ * See README for more details.
+ *
+ * This random number generator is used to provide additional entropy to the
+ * one provided by the operating system (os_get_random()) for session key
+ * generation. The os_get_random() output is expected to be secure and the
+ * implementation here is expected to provide only limited protection against
+ * cases where os_get_random() cannot provide strong randomness. This
+ * implementation shall not be assumed to be secure as the sole source of
+ * randomness. The random_get_bytes() function mixes in randomness from
+ * os_get_random() and as such, calls to os_get_random() can be replaced with
+ * calls to random_get_bytes() without reducing security.
+ *
+ * The design here follows partially the design used in the Linux
+ * drivers/char/random.c, but the implementation here is simpler and not as
+ * strong. This is a compromise to reduce duplicated CPU effort and to avoid
+ * extra code/memory size. As pointed out above, os_get_random() needs to be
+ * guaranteed to be secure for any of the security assumptions to hold.
+ */
+
+#include "utils/includes.h"
+#ifdef __linux__
+#include <fcntl.h>
+#ifdef CONFIG_GETRANDOM
+#include <sys/random.h>
+#endif /* CONFIG_GETRANDOM */
+#endif /* __linux__ */
+
+#include "utils/common.h"
+#include "utils/eloop.h"
+#include "crypto/crypto.h"
+#include "sha1.h"
+#include "random.h"
+
+#define POOL_WORDS 32
+#define POOL_WORDS_MASK (POOL_WORDS - 1)
+#define POOL_TAP1 26
+#define POOL_TAP2 20
+#define POOL_TAP3 14
+#define POOL_TAP4 7
+#define POOL_TAP5 1
+#define EXTRACT_LEN 16
+#define MIN_READY_MARK 2
+
+static u32 pool[POOL_WORDS];
+static unsigned int input_rotate = 0;
+static unsigned int pool_pos = 0;
+static u8 stub_key[20];
+#ifdef __linux__
+static size_t stub_key_avail = 0;
+static int random_fd = -1;
+#endif /* __linux__ */
+static unsigned int own_pool_ready = 0;
+#define RANDOM_ENTROPY_SIZE 20
+static char *random_entropy_file = NULL;
+
+#define MIN_COLLECT_ENTROPY 1000
+static unsigned int entropy = 0;
+static unsigned int total_collected = 0;
+
+
+static void random_write_entropy(void);
+
+
+static u32 __ROL32(u32 x, u32 y)
+{
+	if (y == 0)
+		return x;
+
+	return (x << (y & 31)) | (x >> (32 - (y & 31)));
+}
+
+
+static void random_mix_pool(const void *buf, size_t len)
+{
+	static const u32 twist[8] = {
+		0x00000000, 0x3b6e20c8, 0x76dc4190, 0x4db26158,
+		0xedb88320, 0xd6d6a3e8, 0x9b64c2b0, 0xa00ae278
+	};
+	const u8 *pos = buf;
+	u32 w;
+
+	wpa_hexdump_key(MSG_EXCESSIVE, "random_mix_pool", buf, len);
+
+	while (len--) {
+		w = __ROL32(*pos++, input_rotate & 31);
+		input_rotate += pool_pos ? 7 : 14;
+		pool_pos = (pool_pos - 1) & POOL_WORDS_MASK;
+		w ^= pool[pool_pos];
+		w ^= pool[(pool_pos + POOL_TAP1) & POOL_WORDS_MASK];
+		w ^= pool[(pool_pos + POOL_TAP2) & POOL_WORDS_MASK];
+		w ^= pool[(pool_pos + POOL_TAP3) & POOL_WORDS_MASK];
+		w ^= pool[(pool_pos + POOL_TAP4) & POOL_WORDS_MASK];
+		w ^= pool[(pool_pos + POOL_TAP5) & POOL_WORDS_MASK];
+		pool[pool_pos] = (w >> 3) ^ twist[w & 7];
+	}
+}
+
+
+static void random_extract(u8 *out)
+{
+	unsigned int i;
+	u8 hash[SHA1_MAC_LEN];
+	u32 *hash_ptr;
+	u32 buf[POOL_WORDS / 2];
+
+	/* First, add hash back to pool to make backtracking more difficult. */
+	hmac_sha1(stub_key, sizeof(stub_key), (const u8 *) pool,
+		  sizeof(pool), hash);
+	random_mix_pool(hash, sizeof(hash));
+	/* Hash half the pool to extra data */
+	for (i = 0; i < POOL_WORDS / 2; i++)
+		buf[i] = pool[(pool_pos - i) & POOL_WORDS_MASK];
+	hmac_sha1(stub_key, sizeof(stub_key), (const u8 *) buf,
+		  sizeof(buf), hash);
+	/*
+	 * Fold the hash to further reduce any potential output pattern.
+	 * Though, compromise this to reduce CPU use for the most common output
+	 * length (32) and return 16 bytes from instead of only half.
+	 */
+	hash_ptr = (u32 *) hash;
+	hash_ptr[0] ^= hash_ptr[4];
+	os_memcpy(out, hash, EXTRACT_LEN);
+}
+
+
+void random_add_randomness(const void *buf, size_t len)
+{
+	struct os_time t;
+	static unsigned int count = 0;
+
+	count++;
+	if (entropy > MIN_COLLECT_ENTROPY && (count & 0x3ff) != 0) {
+		/*
+		 * No need to add more entropy at this point, so save CPU and
+		 * skip the update.
+		 */
+		return;
+	}
+	wpa_printf(MSG_EXCESSIVE, "Add randomness: count=%u entropy=%u",
+		   count, entropy);
+
+	os_get_time(&t);
+	wpa_hexdump_key(MSG_EXCESSIVE, "random pool",
+			(const u8 *) pool, sizeof(pool));
+	random_mix_pool(&t, sizeof(t));
+	random_mix_pool(buf, len);
+	wpa_hexdump_key(MSG_EXCESSIVE, "random pool",
+			(const u8 *) pool, sizeof(pool));
+	entropy++;
+	total_collected++;
+}
+
+
+int random_get_bytes(void *buf, size_t len)
+{
+	int ret;
+	u8 *bytes = buf;
+	size_t left;
+
+	wpa_printf(MSG_MSGDUMP, "Get randomness: len=%u entropy=%u",
+		   (unsigned int) len, entropy);
+
+	/* Start with assumed strong randomness from OS */
+	ret = os_get_random(buf, len);
+	wpa_hexdump_key(MSG_EXCESSIVE, "random from os_get_random",
+			buf, len);
+
+	/* Mix in additional entropy extracted from the internal pool */
+	left = len;
+	while (left) {
+		size_t siz, i;
+		u8 tmp[EXTRACT_LEN];
+		random_extract(tmp);
+		wpa_hexdump_key(MSG_EXCESSIVE, "random from internal pool",
+				tmp, sizeof(tmp));
+		siz = left > EXTRACT_LEN ? EXTRACT_LEN : left;
+		for (i = 0; i < siz; i++)
+			*bytes++ ^= tmp[i];
+		left -= siz;
+	}
+
+#ifdef CONFIG_FIPS
+	/* Mix in additional entropy from the crypto module */
+	bytes = buf;
+	left = len;
+	while (left) {
+		size_t siz, i;
+		u8 tmp[EXTRACT_LEN];
+		if (crypto_get_random(tmp, sizeof(tmp)) < 0) {
+			wpa_printf(MSG_ERROR, "random: No entropy available "
+				   "for generating strong random bytes");
+			return -1;
+		}
+		wpa_hexdump_key(MSG_EXCESSIVE, "random from crypto module",
+				tmp, sizeof(tmp));
+		siz = left > EXTRACT_LEN ? EXTRACT_LEN : left;
+		for (i = 0; i < siz; i++)
+			*bytes++ ^= tmp[i];
+		left -= siz;
+	}
+#endif /* CONFIG_FIPS */
+
+	wpa_hexdump_key(MSG_EXCESSIVE, "mixed random", buf, len);
+
+	if (entropy < len)
+		entropy = 0;
+	else
+		entropy -= len;
+
+	return ret;
+}
+
+
+int random_pool_ready(void)
+{
+#ifdef __linux__
+	int fd;
+	ssize_t res;
+
+	/*
+	 * Make sure that there is reasonable entropy available before allowing
+	 * some key derivation operations to proceed.
+	 */
+
+	if (stub_key_avail == sizeof(stub_key))
+		return 1; /* Already initialized - good to continue */
+
+	/*
+	 * Try to fetch some more data from the kernel high quality RNG.
+	 * There may not be enough data available at this point,
+	 * so use non-blocking read to avoid blocking the application
+	 * completely.
+	 */
+
+#ifdef CONFIG_GETRANDOM
+	res = getrandom(stub_key + stub_key_avail,
+			sizeof(stub_key) - stub_key_avail, GRND_NONBLOCK);
+	if (res < 0) {
+		if (errno == ENOSYS) {
+			wpa_printf(MSG_DEBUG,
+				   "random: getrandom() not supported, falling back to /dev/random");
+		} else {
+			wpa_printf(MSG_INFO,
+				   "random: no data from getrandom(): %s",
+				   strerror(errno));
+			res = 0;
+		}
+	}
+#else /* CONFIG_GETRANDOM */
+	res = -1;
+#endif /* CONFIG_GETRANDOM */
+	if (res < 0) {
+		fd = open("/dev/random", O_RDONLY | O_NONBLOCK);
+		if (fd < 0) {
+			wpa_printf(MSG_ERROR,
+				   "random: Cannot open /dev/random: %s",
+				   strerror(errno));
+			return -1;
+		}
+
+		res = read(fd, stub_key + stub_key_avail,
+			   sizeof(stub_key) - stub_key_avail);
+		if (res < 0) {
+			wpa_printf(MSG_ERROR,
+				   "random: Cannot read from /dev/random: %s",
+				   strerror(errno));
+			res = 0;
+		}
+		close(fd);
+	}
+
+	wpa_printf(MSG_DEBUG, "random: Got %u/%u random bytes", (unsigned) res,
+		   (unsigned) (sizeof(stub_key) - stub_key_avail));
+	stub_key_avail += res;
+
+	if (stub_key_avail == sizeof(stub_key)) {
+		if (own_pool_ready < MIN_READY_MARK)
+			own_pool_ready = MIN_READY_MARK;
+		random_write_entropy();
+		return 1;
+	}
+
+	wpa_printf(MSG_INFO, "random: Only %u/%u bytes of strong "
+		   "random data available",
+		   (unsigned) stub_key_avail, (unsigned) sizeof(stub_key));
+
+	if (own_pool_ready >= MIN_READY_MARK ||
+	    total_collected + 10 * own_pool_ready > MIN_COLLECT_ENTROPY) {
+		wpa_printf(MSG_INFO, "random: Allow operation to proceed "
+			   "based on internal entropy");
+		return 1;
+	}
+
+	wpa_printf(MSG_INFO, "random: Not enough entropy pool available for "
+		   "secure operations");
+	return 0;
+#else /* __linux__ */
+	/* TODO: could do similar checks on non-Linux platforms */
+	return 1;
+#endif /* __linux__ */
+}
+
+
+void random_mark_pool_ready(void)
+{
+	own_pool_ready++;
+	wpa_printf(MSG_DEBUG, "random: Mark internal entropy pool to be "
+		   "ready (count=%u/%u)", own_pool_ready, MIN_READY_MARK);
+	random_write_entropy();
+}
+
+
+#ifdef __linux__
+
+static void random_close_fd(void)
+{
+	if (random_fd >= 0) {
+		eloop_unregister_read_sock(random_fd);
+		close(random_fd);
+		random_fd = -1;
+	}
+}
+
+
+static void random_read_fd(int sock, void *eloop_ctx, void *sock_ctx)
+{
+	ssize_t res;
+
+	if (stub_key_avail == sizeof(stub_key)) {
+		random_close_fd();
+		return;
+	}
+
+	res = read(sock, stub_key + stub_key_avail,
+		   sizeof(stub_key) - stub_key_avail);
+	if (res < 0) {
+		wpa_printf(MSG_ERROR, "random: Cannot read from /dev/random: "
+			   "%s", strerror(errno));
+		return;
+	}
+
+	wpa_printf(MSG_DEBUG, "random: Got %u/%u bytes from /dev/random",
+		   (unsigned) res,
+		   (unsigned) (sizeof(stub_key) - stub_key_avail));
+	stub_key_avail += res;
+
+	if (stub_key_avail == sizeof(stub_key)) {
+		random_close_fd();
+		if (own_pool_ready < MIN_READY_MARK)
+			own_pool_ready = MIN_READY_MARK;
+		random_write_entropy();
+	}
+}
+
+#endif /* __linux__ */
+
+
+static void random_read_entropy(void)
+{
+	char *buf;
+	size_t len;
+
+	if (!random_entropy_file)
+		return;
+
+	buf = os_readfile(random_entropy_file, &len);
+	if (buf == NULL)
+		return; /* entropy file not yet available */
+
+	if (len != 1 + RANDOM_ENTROPY_SIZE) {
+		wpa_printf(MSG_DEBUG, "random: Invalid entropy file %s",
+			   random_entropy_file);
+		os_free(buf);
+		return;
+	}
+
+	own_pool_ready = (u8) buf[0];
+	random_add_randomness(buf + 1, RANDOM_ENTROPY_SIZE);
+	os_free(buf);
+	wpa_printf(MSG_DEBUG, "random: Added entropy from %s "
+		   "(own_pool_ready=%u)",
+		   random_entropy_file, own_pool_ready);
+}
+
+
+static void random_write_entropy(void)
+{
+	char buf[RANDOM_ENTROPY_SIZE];
+	FILE *f;
+	u8 opr;
+	int fail = 0;
+
+	if (!random_entropy_file)
+		return;
+
+	if (random_get_bytes(buf, RANDOM_ENTROPY_SIZE) < 0)
+		return;
+
+	f = fopen(random_entropy_file, "wb");
+	if (f == NULL) {
+		wpa_printf(MSG_ERROR, "random: Could not open entropy file %s "
+			   "for writing", random_entropy_file);
+		return;
+	}
+
+	opr = own_pool_ready > 0xff ? 0xff : own_pool_ready;
+	if (fwrite(&opr, 1, 1, f) != 1 ||
+	    fwrite(buf, RANDOM_ENTROPY_SIZE, 1, f) != 1)
+		fail = 1;
+	fclose(f);
+	if (fail) {
+		wpa_printf(MSG_ERROR, "random: Could not write entropy data "
+			   "to %s", random_entropy_file);
+		return;
+	}
+
+	wpa_printf(MSG_DEBUG, "random: Updated entropy file %s "
+		   "(own_pool_ready=%u)",
+		   random_entropy_file, own_pool_ready);
+}
+
+
+void random_init(const char *entropy_file)
+{
+	os_free(random_entropy_file);
+	if (entropy_file)
+		random_entropy_file = os_strdup(entropy_file);
+	else
+		random_entropy_file = NULL;
+	random_read_entropy();
+
+#ifdef __linux__
+	if (random_fd >= 0)
+		return;
+
+#ifdef CONFIG_GETRANDOM
+	{
+		u8 stub;
+
+		if (getrandom(&stub, 0, GRND_NONBLOCK) == 0 ||
+		    errno != ENOSYS) {
+			wpa_printf(MSG_DEBUG,
+				   "random: getrandom() support available");
+			return;
+		}
+	}
+#endif /* CONFIG_GETRANDOM */
+
+	random_fd = open("/dev/random", O_RDONLY | O_NONBLOCK);
+	if (random_fd < 0) {
+		wpa_printf(MSG_ERROR, "random: Cannot open /dev/random: %s",
+			   strerror(errno));
+		return;
+	}
+	wpa_printf(MSG_DEBUG, "random: Trying to read entropy from "
+		   "/dev/random");
+
+	eloop_register_read_sock(random_fd, random_read_fd, NULL, NULL);
+#endif /* __linux__ */
+
+	random_write_entropy();
+}
+
+
+void random_deinit(void)
+{
+#ifdef __linux__
+	random_close_fd();
+#endif /* __linux__ */
+	random_write_entropy();
+	os_free(random_entropy_file);
+	random_entropy_file = NULL;
+}