1 files changed, 478 insertions, 0 deletions

diff --git a/chip/g/dcrypto/hmac_drbg.c b/chip/g/dcrypto/hmac_drbg.c
new file mode 100644
index 0000000000..2ca20e03ff
--- /dev/null
+++ b/chip/g/dcrypto/hmac_drbg.c
@@ -0,0 +1,478 @@
+/* Copyright 2018 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "console.h"
+#include "cryptoc/util.h"
+#include "dcrypto.h"
+#include "extension.h"
+#include "internal.h"
+#include "trng.h"
+
+/* HMAC_DRBG flow in NIST SP 800-90Ar1, 10.2, RFC 6979
+ */
+/* V = HMAC(K, V) */
+static void update_v(const uint32_t *k, uint32_t *v)
+{
+	LITE_HMAC_CTX ctx;
+
+	DCRYPTO_HMAC_SHA256_init(&ctx, k, SHA256_DIGEST_SIZE);
+	HASH_update(&ctx.hash, v, SHA256_DIGEST_SIZE);
+	memcpy(v, DCRYPTO_HMAC_final(&ctx), SHA256_DIGEST_SIZE);
+}
+
+/* K = HMAC(K, V || tag || p0 || p1 || p2) */
+/* V = HMAC(K, V) */
+static void update_kv(uint32_t *k, uint32_t *v, uint8_t tag,
+		      const void *p0, size_t p0_len,
+		      const void *p1, size_t p1_len,
+		      const void *p2, size_t p2_len)
+{
+	LITE_HMAC_CTX ctx;
+
+	DCRYPTO_HMAC_SHA256_init(&ctx, k, SHA256_DIGEST_SIZE);
+	HASH_update(&ctx.hash, v, SHA256_DIGEST_SIZE);
+	HASH_update(&ctx.hash, &tag, 1);
+	HASH_update(&ctx.hash, p0, p0_len);
+	HASH_update(&ctx.hash, p1, p1_len);
+	HASH_update(&ctx.hash, p2, p2_len);
+	memcpy(k, DCRYPTO_HMAC_final(&ctx), SHA256_DIGEST_SIZE);
+
+	update_v(k, v);
+}
+
+static void update(struct drbg_ctx *ctx,
+		   const void *p0, size_t p0_len,
+		   const void *p1, size_t p1_len,
+		   const void *p2, size_t p2_len)
+{
+	/* K = HMAC(K, V || 0x00 || provided_data) */
+	/* V = HMAC(K, V) */
+	update_kv(ctx->k, ctx->v, 0x00,
+		  p0, p0_len, p1, p1_len, p2, p2_len);
+
+	/* If no provided_data, stop. */
+	if (p0_len + p1_len + p2_len == 0)
+		return;
+
+	/* K = HMAC(K, V || 0x01 || provided_data) */
+	/* V = HMAC(K, V) */
+	update_kv(ctx->k, ctx->v,
+		  0x01,
+		  p0, p0_len, p1, p1_len, p2, p2_len);
+}
+
+void hmac_drbg_init(struct drbg_ctx *ctx,
+		    const void *p0, size_t p0_len,
+		    const void *p1, size_t p1_len,
+		    const void *p2, size_t p2_len)
+{
+	/* K = 0x00 0x00 0x00 ... 0x00 */
+	always_memset(ctx->k,  0x00, sizeof(ctx->k));
+	/* V = 0x01 0x01 0x01 ... 0x01 */
+	always_memset(ctx->v,  0x01, sizeof(ctx->v));
+
+	update(ctx, p0, p0_len, p1, p1_len, p2, p2_len);
+
+	ctx->reseed_counter = 1;
+}
+
+void hmac_drbg_init_rfc6979(struct drbg_ctx *ctx, const p256_int *key,
+			    const p256_int *message)
+{
+	hmac_drbg_init(ctx,
+		       key->a, sizeof(key->a),
+		       message->a, sizeof(message->a),
+		       NULL, 0);
+}
+
+void hmac_drbg_init_rand(struct drbg_ctx *ctx, size_t nbits)
+{
+	int i;
+	uint32_t x[(nbits + 31) / 32];
+
+	for (i = 0; i < ARRAY_SIZE(x); ++i)
+		x[i] = rand();
+
+	hmac_drbg_init(ctx, &x, sizeof(x), NULL, 0, NULL, 0);
+}
+
+void hmac_drbg_reseed(struct drbg_ctx *ctx,
+		      const void *p0, size_t p0_len,
+		      const void *p1, size_t p1_len,
+		      const void *p2, size_t p2_len)
+{
+	update(ctx, p0, p0_len, p1, p1_len, p2, p2_len);
+	ctx->reseed_counter = 1;
+}
+
+enum hmac_result hmac_drbg_generate(struct drbg_ctx *ctx,
+		       void *out, size_t out_len,
+		       const void *input, size_t input_len)
+{
+	/* According to NIST SP 800-90A rev 1 B.2
+	 * Maximum number of bits per request = 7500 bits
+	 * Reseed_interval = 10 000 requests.
+	 */
+	if (out_len > 7500 / 8)
+		return HMAC_DRBG_INVALID_PARAM;
+
+	if (ctx->reseed_counter++ >= 10000)
+		return HMAC_DRBG_RESEED_REQUIRED;
+
+	if (input_len)
+		update(ctx, input, input_len, NULL, 0, NULL, 0);
+
+	while (out_len) {
+		size_t n = out_len > sizeof(ctx->v) ? sizeof(ctx->v) : out_len;
+
+		update_v(ctx->k, ctx->v);
+
+		memcpy(out, ctx->v, n);
+		out += n;
+		out_len -= n;
+	}
+
+	update(ctx, input, input_len, NULL, 0, NULL, 0);
+
+	return HMAC_DRBG_SUCCESS;
+}
+
+enum hmac_result hmac_drbg_generate_p256(struct drbg_ctx *ctx, p256_int *k_out)
+{
+	return hmac_drbg_generate(ctx, k_out->a, sizeof(k_out->a), NULL, 0);
+}
+
+void drbg_exit(struct drbg_ctx *ctx)
+{
+	always_memset(ctx->k,  0x00, sizeof(ctx->k));
+	always_memset(ctx->v,  0x00, sizeof(ctx->v));
+}
+
+#ifdef CRYPTO_TEST_SETUP
+
+/*
+ * from the RFC 6979 A.2.5 example:
+ *
+ * curve: NIST P-256
+ *
+ * q = FFFFFFFF00000000FFFFFFFFFFFFFFFFBCE6FAADA7179E84F3B9CAC2FC632551
+ * (qlen = 256 bits)
+ *
+ * private key:
+ * x = C9AFA9D845BA75166B5C215767B1D6934E50C3DB36E89B127B8A622B120F6721
+ *
+ * public key: U = xG
+ * Ux = 60FED4BA255A9D31C961EB74C6356D68C049B8923B61FA6CE669622E60F29FB6
+ * Uy = 7903FE1008B8BC99A41AE9E95628BC64F2F1B20C2D7E9F5177A3C294D4462299
+ *
+ * Signature:
+ * With SHA-256, message = "sample":
+ * k = A6E3C57DD01ABE90086538398355DD4C3B17AA873382B0F24D6129493D8AAD60
+ * r = EFD48B2AACB6A8FD1140DD9CD45E81D69D2C877B56AAF991C34D0EA84EAF3716
+ * s = F7CB1C942D657C41D436C7A1B6E29F65F3E900DBB9AFF4064DC4AB2F843ACDA8
+ */
+static int cmd_rfc6979(int argc, char **argv)
+{
+	static p256_int h1;
+	static p256_int k;
+	static const char message[] = "sample";
+	static struct drbg_ctx drbg;
+
+	static HASH_CTX ctx;
+	int result;
+	static const uint8_t priv_from_rfc[] = {
+		0xC9, 0xAF, 0xA9, 0xD8, 0x45, 0xBA, 0x75, 0x16,
+		0x6B, 0x5C, 0x21, 0x57, 0x67, 0xB1, 0xD6, 0x93,
+		0x4E, 0x50, 0xC3, 0xDB, 0x36, 0xE8, 0x9B, 0x12,
+		0x7B, 0x8A, 0x62, 0x2B, 0x12, 0x0F, 0x67, 0x21
+	};
+	static const uint8_t k_from_rfc[] = {
+		0xA6, 0xE3, 0xC5, 0x7D, 0xD0, 0x1A, 0xBE, 0x90,
+		0x08, 0x65, 0x38, 0x39, 0x83, 0x55, 0xDD, 0x4C,
+		0x3B, 0x17, 0xAA, 0x87, 0x33, 0x82, 0xB0, 0xF2,
+		0x4D, 0x61, 0x29, 0x49, 0x3D, 0x8A, 0xAD, 0x60
+	};
+	p256_int *x = (p256_int *)priv_from_rfc;
+	p256_int *reference_k = (p256_int *)k_from_rfc;
+
+	/* h1 = H(m) */
+	DCRYPTO_SHA256_init(&ctx, 1);
+	HASH_update(&ctx, message, sizeof(message) - 1);
+	memcpy(&h1, HASH_final(&ctx), SHA256_DIGEST_SIZE);
+
+	hmac_drbg_init_rfc6979(&drbg, x, &h1);
+	do {
+		hmac_drbg_generate_p256(&drbg, &k);
+		ccprintf("K = %ph\n", HEX_BUF(&k, 32));
+	} while (p256_cmp(&SECP256r1_nMin2, &k) < 0);
+	drbg_exit(&drbg);
+	result = p256_cmp(&k, reference_k);
+	ccprintf("K generation: %s\n", result ? "FAIL" : "PASS");
+
+	return result ? EC_ERROR_INVAL : EC_SUCCESS;
+}
+DECLARE_SAFE_CONSOLE_COMMAND(rfc6979, cmd_rfc6979, NULL, NULL);
+
+/*
+ * Test vectors from the NIST Cryptographic Algorithm Validation Program.
+ *
+ * These are the first two examples from the SHA-256, without prediction
+ * resistance, and with reseed supported.
+ */
+#define HMAC_TEST_COUNT 2
+static int cmd_hmac_drbg(int argc, char **argv)
+{
+	static struct drbg_ctx ctx;
+
+	static const uint8_t init_entropy[HMAC_TEST_COUNT][32] = {
+		{
+			0x06, 0x03, 0x2C, 0xD5, 0xEE, 0xD3, 0x3F, 0x39, 0x26,
+			0x5F, 0x49, 0xEC, 0xB1, 0x42, 0xC5, 0x11, 0xDA, 0x9A,
+			0xFF, 0x2A, 0xF7, 0x12, 0x03, 0xBF, 0xFA, 0xF3, 0x4A,
+			0x9C, 0xA5, 0xBD, 0x9C, 0x0D
+		},
+		{
+			0xAA, 0xDC, 0xF3, 0x37, 0x78, 0x8B, 0xB8, 0xAC, 0x01,
+			0x97, 0x66, 0x40, 0x72, 0x6B, 0xC5, 0x16, 0x35, 0xD4,
+			0x17, 0x77, 0x7F, 0xE6, 0x93, 0x9E, 0xDE, 0xD9, 0xCC,
+			0xC8, 0xA3, 0x78, 0xC7, 0x6A
+		},
+	};
+
+	static const uint8_t init_nonce[HMAC_TEST_COUNT][16] = {
+		{
+			0x0E, 0x66, 0xF7, 0x1E, 0xDC, 0x43, 0xE4, 0x2A, 0x45,
+			0xAD, 0x3C, 0x6F, 0xC6, 0xCD, 0xC4, 0xDF
+		},
+		{
+			0x9C, 0xCC, 0x9D, 0x80, 0xC8, 0x9A, 0xC5, 0x5A, 0x8C,
+			0xFE, 0x0F, 0x99, 0x94, 0x2F, 0x5A, 0x4D
+		},
+	};
+
+	static const uint8_t reseed_entropy[HMAC_TEST_COUNT][32] = {
+		{
+			0x01, 0x92, 0x0A, 0x4E, 0x66, 0x9E, 0xD3, 0xA8, 0x5A,
+			0xE8, 0xA3, 0x3B, 0x35, 0xA7, 0x4A, 0xD7, 0xFB, 0x2A,
+			0x6B, 0xB4, 0xCF, 0x39, 0x5C, 0xE0, 0x03, 0x34, 0xA9,
+			0xC9, 0xA5, 0xA5, 0xD5, 0x52
+		},
+		{
+			0x03, 0xA5, 0x77, 0x92, 0x54, 0x7E, 0x0C, 0x98, 0xEA,
+			0x17, 0x76, 0xE4, 0xBA, 0x80, 0xC0, 0x07, 0x34, 0x62,
+			0x96, 0xA5, 0x6A, 0x27, 0x0A, 0x35, 0xFD, 0x9E, 0xA2,
+			0x84, 0x5C, 0x7E, 0x81, 0xE2
+		}
+	};
+
+	static const uint8_t expected_output[HMAC_TEST_COUNT][128] = {
+		{
+			0x76, 0xFC, 0x79, 0xFE, 0x9B, 0x50, 0xBE, 0xCC, 0xC9,
+			0x91, 0xA1, 0x1B, 0x56, 0x35, 0x78, 0x3A, 0x83, 0x53,
+			0x6A, 0xDD, 0x03, 0xC1, 0x57, 0xFB, 0x30, 0x64, 0x5E,
+			0x61, 0x1C, 0x28, 0x98, 0xBB, 0x2B, 0x1B, 0xC2, 0x15,
+			0x00, 0x02, 0x09, 0x20, 0x8C, 0xD5, 0x06, 0xCB, 0x28,
+			0xDA, 0x2A, 0x51, 0xBD, 0xB0, 0x38, 0x26, 0xAA, 0xF2,
+			0xBD, 0x23, 0x35, 0xD5, 0x76, 0xD5, 0x19, 0x16, 0x08,
+			0x42, 0xE7, 0x15, 0x8A, 0xD0, 0x94, 0x9D, 0x1A, 0x9E,
+			0xC3, 0xE6, 0x6E, 0xA1, 0xB1, 0xA0, 0x64, 0xB0, 0x05,
+			0xDE, 0x91, 0x4E, 0xAC, 0x2E, 0x9D, 0x4F, 0x2D, 0x72,
+			0xA8, 0x61, 0x6A, 0x80, 0x22, 0x54, 0x22, 0x91, 0x82,
+			0x50, 0xFF, 0x66, 0xA4, 0x1B, 0xD2, 0xF8, 0x64, 0xA6,
+			0xA3, 0x8C, 0xC5, 0xB6, 0x49, 0x9D, 0xC4, 0x3F, 0x7F,
+			0x2B, 0xD0, 0x9E, 0x1E, 0x0F, 0x8F, 0x58, 0x85, 0x93,
+			0x51, 0x24
+		},
+		{
+			0x17, 0xD0, 0x9F, 0x40, 0xA4, 0x37, 0x71, 0xF4, 0xA2,
+			0xF0, 0xDB, 0x32, 0x7D, 0xF6, 0x37, 0xDE, 0xA9, 0x72,
+			0xBF, 0xFF, 0x30, 0xC9, 0x8E, 0xBC, 0x88, 0x42, 0xDC,
+			0x7A, 0x9E, 0x3D, 0x68, 0x1C, 0x61, 0x90, 0x2F, 0x71,
+			0xBF, 0xFA, 0xF5, 0x09, 0x36, 0x07, 0xFB, 0xFB, 0xA9,
+			0x67, 0x4A, 0x70, 0xD0, 0x48, 0xE5, 0x62, 0xEE, 0x88,
+			0xF0, 0x27, 0xF6, 0x30, 0xA7, 0x85, 0x22, 0xEC, 0x6F,
+			0x70, 0x6B, 0xB4, 0x4A, 0xE1, 0x30, 0xE0, 0x5C, 0x8D,
+			0x7E, 0xAC, 0x66, 0x8B, 0xF6, 0x98, 0x0D, 0x99, 0xB4,
+			0xC0, 0x24, 0x29, 0x46, 0x45, 0x23, 0x99, 0xCB, 0x03,
+			0x2C, 0xC6, 0xF9, 0xFD, 0x96, 0x28, 0x47, 0x09, 0xBD,
+			0x2F, 0xA5, 0x65, 0xB9, 0xEB, 0x9F, 0x20, 0x04, 0xBE,
+			0x6C, 0x9E, 0xA9, 0xFF, 0x91, 0x28, 0xC3, 0xF9, 0x3B,
+			0x60, 0xDC, 0x30, 0xC5, 0xFC, 0x85, 0x87, 0xA1, 0x0D,
+			0xE6, 0x8C
+		}
+	};
+
+	static uint8_t output[128];
+
+	int i, cmp_result;
+
+	for (i = 0; i < HMAC_TEST_COUNT; i++) {
+		hmac_drbg_init(&ctx,
+			       init_entropy[i], sizeof(init_entropy[i]),
+			       init_nonce[i], sizeof(init_nonce[i]),
+			       NULL, 0);
+
+		hmac_drbg_reseed(&ctx,
+				 reseed_entropy[i], sizeof(reseed_entropy[i]),
+				 NULL, 0,
+				 NULL, 0);
+
+		hmac_drbg_generate(&ctx,
+				   output, sizeof(output),
+				   NULL, 0);
+
+		hmac_drbg_generate(&ctx,
+				   output, sizeof(output),
+				   NULL, 0);
+
+		cmp_result = memcmp(output, expected_output[i], sizeof(output));
+		ccprintf("HMAC DRBG generate test %d, %s\n",
+			 i, cmp_result ? "failed" : "passed");
+	}
+
+	return 0;
+}
+DECLARE_SAFE_CONSOLE_COMMAND(hmac_drbg, cmd_hmac_drbg, NULL, NULL);
+
+/*
+ * Sanity check to exercise random initialization.
+ */
+static int cmd_hmac_drbg_rand(int argc, char **argv)
+{
+	static struct drbg_ctx ctx;
+	static uint8_t output[128];
+
+	int i;
+
+	hmac_drbg_init_rand(&ctx, 256);
+
+	hmac_drbg_generate(&ctx, output, sizeof(output), NULL, 0);
+
+	ccprintf("Randomly initialized HMAC DRBG, 1024 bit output: ");
+
+	for (i = 0; i < sizeof(output); i++)
+		ccprintf("%x", output[i]);
+	ccprintf("\n");
+
+	return 0;
+}
+DECLARE_SAFE_CONSOLE_COMMAND(hmac_drbg_rand, cmd_hmac_drbg_rand, NULL, NULL);
+
+enum drbg_command {
+	DRBG_INIT = 0,
+	DRBG_RESEED = 1,
+	DRBG_GENERATE = 2
+};
+
+/*
+ * DRBG_TEST command structure:
+ *
+ * field       |    size  |              note
+ * ==========================================================================
+ * mode        |    1     | 0 - DRBG_INIT, 1 - DRBG_RESEED, 2 - DRBG_GENERATE
+ * p0_len      |    2     | size of first input in bytes
+ * p0          |  p0_len  | entropy for INIT & SEED, input for GENERATE
+ * p1_len      |    2     | size of second input in bytes (for INIT & RESEED)
+ *             |          | or size of expected output for GENERATE
+ * p1          |  p1_len  | nonce for INIT & SEED
+ * p2_len      |    2     | size of third input in bytes for DRBG_INIT
+ * p2          |  p2_len  | personalization for INIT & SEED
+ *
+ * DRBG_INIT (entropy, nonce, perso)
+ * DRBG_RESEED (entropy, additional input 1, additional input 2)
+ * DRBG_INIT and DRBG_RESEED returns empty response
+ * DRBG_GENERATE (p0_len, p0 - additional input 1, p1_len - size of output)
+ * DRBG_GENERATE returns p1_len bytes of generated data
+ * (up to a maximum of 128 bytes)
+ */
+static enum vendor_cmd_rc drbg_test(enum vendor_cmd_cc code, void *buf,
+				    size_t input_size, size_t *response_size)
+{
+	static struct drbg_ctx drbg_ctx;
+	static uint8_t output[512];
+	uint8_t *p0 = NULL, *p1 = NULL, *p2 = NULL;
+	uint16_t p0_len = 0, p1_len = 0, p2_len = 0;
+	uint8_t *cmd = (uint8_t *)buf;
+	size_t max_out_len = *response_size;
+	enum drbg_command drbg_op;
+
+	*response_size = 0;
+	/* there is always op + first parameter, even if zero length */
+	if (input_size < sizeof(p0_len) + 1)
+		return VENDOR_RC_BOGUS_ARGS;
+	drbg_op = *cmd++;
+	p0_len = *cmd++;
+	p0_len = p0_len * 256 + *cmd++;
+	input_size -= 3;
+	if (p0_len > input_size)
+		return VENDOR_RC_BOGUS_ARGS;
+	input_size -= p0_len;
+	if (p0_len)
+		p0 = cmd;
+	cmd += p0_len;
+
+	/* there should be enough space for p1_len */
+	if (input_size && input_size < sizeof(p1_len))
+		return VENDOR_RC_BOGUS_ARGS;
+
+	/* DRBG_GENERATE should just have p1_len defined */
+	if (drbg_op == DRBG_GENERATE && input_size != sizeof(p1_len))
+		return VENDOR_RC_BOGUS_ARGS;
+
+	if (input_size) {
+		p1_len = *cmd++;
+		p1_len = p1_len * 256 + *cmd++;
+		input_size -= 2;
+
+		if (drbg_op != DRBG_GENERATE) {
+			if (p1_len > input_size)
+				return VENDOR_RC_BOGUS_ARGS;
+			input_size -= p1_len;
+			if (p1_len)
+				p1 = cmd;
+			cmd += p1_len;
+		}
+	}
+
+	if (input_size) {
+		if (drbg_op == DRBG_GENERATE)
+			return VENDOR_RC_BOGUS_ARGS;
+		p2_len = *cmd++;
+		p2_len = p2_len * 256 + *cmd++;
+		input_size -= 2;
+		if (p2_len > input_size)
+			return VENDOR_RC_BOGUS_ARGS;
+		if (p2_len)
+			p2 = cmd;
+	}
+
+	switch (drbg_op) {
+	case DRBG_INIT: {
+		hmac_drbg_init(&drbg_ctx, p0, p0_len, p1, p1_len, p2, p2_len);
+		break;
+	}
+	case DRBG_RESEED: {
+		hmac_drbg_reseed(&drbg_ctx, p0, p0_len, p1, p1_len, p2, p2_len);
+		break;
+	}
+	case DRBG_GENERATE: {
+		if (p1_len > sizeof(output) || max_out_len < p1_len)
+			return VENDOR_RC_BOGUS_ARGS;
+
+		hmac_drbg_generate(&drbg_ctx, output, p1_len, p0, p0_len);
+
+		memcpy(buf, output, p1_len);
+		*response_size = p1_len;
+		break;
+	}
+	default:
+		return VENDOR_RC_BOGUS_ARGS;
+	}
+
+	return VENDOR_RC_SUCCESS;
+}
+DECLARE_VENDOR_COMMAND(VENDOR_CC_DRBG_TEST, drbg_test);
+
+#endif /* CRYPTO_TEST_SETUP */