Add more sm4 modes

Not tested yet

CMakeLists.txt

@@ -268,6 +268,10 @@ if (ENABLE_SM4_AESNI_AVX)
 	set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -march=native")
 endif()
 
+option(ENABLE_SM4_MORE_MODES "Enable SM4 ECB/CFB/OFB/CCM modes" OFF)
+if (ENABLE_SM4_MORE_MODES)
+	list(APPEND src src/sm4_ecb.c src/sm4_cfb.c src/sm4_ofb.c src/sm4_ccm.c)
+endif()
 
 option(ENABLE_SM2_EXTS "Enable SM2 Extensions" OFF)
 if (ENABLE_SM2_EXTS)

src/sm4_ccm.c

@@ -0,0 +1,122 @@
+/*
+ *  Copyright 2014-2024 The GmSSL Project. All Rights Reserved.
+ *
+ *  Licensed under the Apache License, Version 2.0 (the License); you may
+ *  not use this file except in compliance with the License.
+ *
+ *  http://www.apache.org/licenses/LICENSE-2.0
+ */
+
+
+#include <gmssl/sm4.h>
+#include <gmssl/mem.h>
+#include <gmssl/sm4_cbc_mac.h>
+#include <gmssl/error.h>
+
+
+#define SM4_CCM_MIN_IV_SIZE 7
+#define SM4_CCM_MAX_IV_SIZE 13
+#define SM4_CCM_MIN_MAC_SIZE 4
+#define SM4_CCM_MAX_MAC_SIZE 16
+
+
+static void length_to_bytes(size_t len, size_t nbytes, uint8_t *out)
+{
+	uint8_t *p = out + nbytes;
+	while (nbytes--) {
+		*p-- = len & 0xff;
+		len >>= 8;
+	}
+}
+
+int sm4_ccm_encrypt(SM4_KEY *sm4_key, const uint8_t *iv, size_t ivlen,
+	const uint8_t *aad, size_t aadlen, const uint8_t *in, size_t inlen,
+	uint8_t *out, size_t taglen, uint8_t *tag)
+{
+	SM4_CBC_MAC_CTX cbc_mac_ctx;
+	size_t inlen_size;
+	uint8_t block[16] = {0};
+	uint8_t ctr[16] = {0};
+	uint8_t S0[16];
+	uint8_t cbc_mac[16];
+	const uint8_t zeros[16] = {0};
+	size_t padding_len;
+
+	if (ivlen < 7 || ivlen > 13) {
+		error_print();
+		return -1;
+	}
+	if (!aad && aadlen) {
+		error_print();
+		return -1;
+	}
+	if (taglen < 4 || taglen > 16 || taglen & 1) {
+		error_print();
+		return -1;
+	}
+
+	inlen_size = 15 - ivlen;
+	if (inlen >= (1 << (inlen_size * 8))) {
+		error_print();
+		return -1;
+	}
+
+	// sm4_cbc_mac_init
+	memset(&cbc_mac_ctx, 0, sizeof(cbc_mac_ctx));
+	cbc_mac_ctx.key = *sm4_key;
+
+	// first block
+	block[0] |= ((aadlen > 0) & 0x1) << 6;
+	block[0] |= (((taglen - 2)/2) & 0x7) << 3;
+	block[0] |= (inlen_size - 1) & 0x7;
+	memcpy(block + 1, iv, ivlen);
+	length_to_bytes(inlen, inlen_size, block + 1 + ivlen);
+	sm4_cbc_mac_update(&cbc_mac_ctx, block, 16);
+
+	if (aad && aadlen) {
+		size_t alen;
+
+		if (aadlen < ((1<<16) - (1<<8))) {
+			length_to_bytes(aadlen, 2, block);
+			alen = 2;
+		} else if (aadlen < ((size_t)1<<32)) {
+			block[0] = 0xff;
+			block[1] = 0xfe;
+			length_to_bytes(aadlen, 4, block + 2);
+			alen = 6;
+		} else {
+			block[0] = 0xff;
+			block[1] = 0xff;
+			length_to_bytes(aadlen, 8, block + 2);
+		}
+		sm4_cbc_mac_update(&cbc_mac_ctx, block, alen);
+
+		sm4_cbc_mac_update(&cbc_mac_ctx, aad, aadlen);
+
+		if (alen + aadlen % 16) {
+			sm4_cbc_mac_update(&cbc_mac_ctx, zeros, 16 - (alen + aadlen)%16);
+		}
+	}
+
+	sm4_cbc_mac_update(&cbc_mac_ctx, in, inlen);
+
+	if (inlen % 16) {
+		sm4_cbc_mac_update(&cbc_mac_ctx, zeros, 16 - inlen%16);
+	}
+	sm4_cbc_mac_finish(&cbc_mac_ctx, cbc_mac);
+
+	ctr[0] = 0;
+	ctr[0] |= (inlen_size - 1) & 0x7;
+	memcpy(ctr + 1, iv, ivlen);
+	memset(ctr + 1 + ivlen, 0, 15 - ivlen);
+
+	sm4_encrypt(sm4_key, ctr, S0);
+	gmssl_memxor(out, cbc_mac, S0, taglen);
+
+	ctr[15] = 1;
+	sm4_ctr_encrypt(sm4_key, ctr, in, inlen, out);
+
+	gmssl_secure_clear(&cbc_mac_ctx, sizeof(cbc_mac_ctx));
+	return 1;
+}
+

src/sm4_cfb.c

@@ -0,0 +1,209 @@
+/*
+ *  Copyright 2014-2024 The GmSSL Project. All Rights Reserved.
+ *
+ *  Licensed under the Apache License, Version 2.0 (the License); you may
+ *  not use this file except in compliance with the License.
+ *
+ *  http://www.apache.org/licenses/LICENSE-2.0
+ */
+
+
+#include <gmssl/sm4.h>
+#include <gmssl/mem.h>
+#include <gmssl/error.h>
+
+
+void sm4_cfb_encrypt(const SM4_KEY *key, size_t sbytes, uint8_t iv[16],
+	const uint8_t *in, size_t inlen, uint8_t *out)
+{
+	uint8_t block[16];
+	size_t len, i;
+
+	// assert(1 <= sbytes && sbytes <= 16);
+
+	while (inlen) {
+		len = inlen < sbytes ? inlen : sbytes;
+		sm4_encrypt(key, iv, block);
+		gmssl_memxor(out, in, block, len);
+
+		// iv = (iv << sbytes) | out
+		for (i = 0; i < 16 - sbytes; i++) {
+			iv[i] = iv[sbytes + i];
+		}
+		memcpy(iv + i, out, len);
+
+		in += len;
+		out += len;
+		inlen -= len;
+	}
+}
+
+void sm4_cfb_decrypt(const SM4_KEY *key, size_t sbytes, uint8_t iv[16],
+	const uint8_t *in, size_t inlen, uint8_t *out)
+{
+	uint8_t block[16];
+	size_t len, i;
+
+	// assert(1 <= sbytes && sbytes <= 16);
+
+	while (inlen) {
+		len = inlen < sbytes ? inlen : sbytes;
+		sm4_encrypt(key, iv, block);
+		gmssl_memxor(out, in, block, len);
+
+		// iv = (iv << sbytes) | in
+		for (i = 0; i < 16 - sbytes; i++) {
+			iv[i] = iv[sbytes + i];
+		}
+		memcpy(iv + i, in, len);
+
+		in += len;
+		out += len;
+		inlen -= len;
+	}
+}
+
+typedef struct {
+	SM4_KEY sm4_key;
+	uint8_t iv[SM4_BLOCK_SIZE];
+	uint8_t block[SM4_BLOCK_SIZE];
+	size_t block_nbytes;
+	size_t sbytes;
+} SM4_CFB_CTX;
+
+int sm4_cfb_encrypt_init(SM4_CFB_CTX *ctx, size_t sbytes,
+	const uint8_t key[SM4_BLOCK_SIZE], const uint8_t iv[SM4_BLOCK_SIZE])
+{
+	if (sbytes < 1 || sbytes > 16) {
+		error_print();
+		return -1;
+	}
+	sm4_set_encrypt_key(&ctx->sm4_key, key);
+	memcpy(ctx->iv, iv, SM4_BLOCK_SIZE);
+	memset(ctx->block, 0, SM4_BLOCK_SIZE);
+	ctx->block_nbytes = 0;
+	ctx->sbytes = sbytes;
+	return 1;
+}
+
+int sm4_cfb_encrypt_update(SM4_CFB_CTX *ctx,
+	const uint8_t *in, size_t inlen, uint8_t *out, size_t *outlen)
+{
+	size_t left;
+	size_t nblocks;
+	size_t len;
+
+	if (ctx->block_nbytes >= ctx->sbytes) {
+		error_print();
+		return -1;
+	}
+	*outlen = 0;
+	if (ctx->block_nbytes) {
+		left = ctx->sbytes - ctx->block_nbytes;
+		if (inlen < left) {
+			memcpy(ctx->block + ctx->block_nbytes, in, inlen);
+			ctx->block_nbytes += inlen;
+			return 1;
+		}
+		memcpy(ctx->block + ctx->block_nbytes, in, left);
+		sm4_cfb_encrypt(&ctx->sm4_key, ctx->sbytes, ctx->iv, ctx->block, ctx->sbytes, out);
+		in += left;
+		inlen -= left;
+		out += ctx->sbytes;
+		*outlen += ctx->sbytes;
+	}
+	if (inlen >= ctx->sbytes) {
+		nblocks = inlen / ctx->sbytes;
+		len = nblocks * ctx->sbytes;
+		sm4_cfb_encrypt(&ctx->sm4_key, ctx->sbytes, ctx->iv, in, len, out);
+		in += len;
+		inlen -= len;
+		out += len;
+		*outlen += len;
+	}
+	if (inlen) {
+		memcpy(ctx->block, in, inlen);
+	}
+	ctx->block_nbytes = inlen;
+	return 1;
+}
+
+int sm4_cfb_encrypt_finish(SM4_CFB_CTX *ctx, uint8_t *out, size_t *outlen)
+{
+	if (ctx->block_nbytes >= ctx->sbytes) {
+		error_print();
+		return -1;
+	}
+	sm4_cfb_encrypt(&ctx->sm4_key, ctx->sbytes, ctx->iv, ctx->block, ctx->block_nbytes, out);
+	*outlen = ctx->block_nbytes;
+	return 1;
+}
+
+int sm4_cfb_decrypt_init(SM4_CFB_CTX *ctx, size_t sbytes,
+	const uint8_t key[SM4_BLOCK_SIZE], const uint8_t iv[SM4_BLOCK_SIZE])
+{
+	if (sbytes < 1 || sbytes > 16) {
+		error_print();
+		return -1;
+	}
+	sm4_set_encrypt_key(&ctx->sm4_key, key);
+	memcpy(ctx->iv, iv, SM4_BLOCK_SIZE);
+	memset(ctx->block, 0, SM4_BLOCK_SIZE);
+	ctx->block_nbytes = 0;
+	ctx->sbytes = sbytes;
+	return 1;
+}
+
+int sm4_cfb_decrypt_update(SM4_CFB_CTX *ctx,
+	const uint8_t *in, size_t inlen, uint8_t *out, size_t *outlen)
+{
+	size_t left;
+	size_t nblocks;
+	size_t len;
+
+	if (ctx->block_nbytes >= ctx->sbytes) {
+		error_print();
+		return -1;
+	}
+	*outlen = 0;
+	if (ctx->block_nbytes) {
+		left = ctx->sbytes - ctx->block_nbytes;
+		if (inlen < left) {
+			memcpy(ctx->block + ctx->block_nbytes, in, inlen);
+			ctx->block_nbytes += inlen;
+			return 1;
+		}
+		memcpy(ctx->block + ctx->block_nbytes, in, left);
+		sm4_cfb_decrypt(&ctx->sm4_key, ctx->sbytes, ctx->iv, ctx->block, ctx->sbytes, out);
+		in += left;
+		inlen -= left;
+		out += ctx->sbytes;
+		*outlen += ctx->sbytes;
+	}
+	if (inlen >= ctx->sbytes) {
+		nblocks = inlen / ctx->sbytes;
+		len = nblocks * ctx->sbytes;
+		sm4_cfb_decrypt(&ctx->sm4_key, ctx->sbytes, ctx->iv, in, len, out);
+		in += len;
+		inlen -= len;
+		out += len;
+		*outlen += len;
+	}
+	if (inlen) {
+		memcpy(ctx->block, in, inlen);
+	}
+	ctx->block_nbytes = inlen;
+	return 1;
+}
+
+int sm4_cfb_decrypt_finish(SM4_CFB_CTX *ctx, uint8_t *out, size_t *outlen)
+{
+	if (ctx->block_nbytes >= ctx->sbytes) {
+		error_print();
+		return -1;
+	}
+	sm4_cfb_decrypt(&ctx->sm4_key, ctx->sbytes, ctx->iv, ctx->block, ctx->block_nbytes, out);
+	*outlen = ctx->block_nbytes;
+	return 1;
+}
+