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Delete sm9_lib.c
This commit is contained in:
Zhi Guan
514
src/sm9_lib.c
514
src/sm9_lib.c
@@ -1,514 +0,0 @@
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/*
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* Copyright 2014-2022 The GmSSL Project. All Rights Reserved.
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*
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* Licensed under the Apache License, Version 2.0 (the License); you may
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* not use this file except in compliance with the License.
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*/
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#include <stdio.h>
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#include <string.h>
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#include <stdlib.h>
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#include <stdint.h>
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#include <gmssl/mem.h>
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#include <gmssl/sm3.h>
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#include <gmssl/sm9.h>
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#include <gmssl/asn1.h>
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#include <gmssl/error.h>
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extern const sm9_bn_t SM9_ZERO;
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extern const sm9_bn_t SM9_N;
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extern const SM9_POINT *SM9_P1;
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extern const SM9_TWIST_POINT *SM9_P2;
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int sm9_signature_to_der(const SM9_SIGNATURE *sig, uint8_t **out, size_t *outlen)
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{
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uint8_t hbuf[32];
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uint8_t Sbuf[65];
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size_t len = 0;
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sm9_fn_to_bytes(sig->h, hbuf);
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sm9_point_to_uncompressed_octets(&sig->S, Sbuf);
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if (asn1_octet_string_to_der(hbuf, sizeof(hbuf), NULL, &len) != 1
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|| asn1_bit_octets_to_der(Sbuf, sizeof(Sbuf), NULL, &len) != 1
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|| asn1_sequence_header_to_der(len, out, outlen) != 1
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|| asn1_octet_string_to_der(hbuf, sizeof(hbuf), out, outlen) != 1
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|| asn1_bit_octets_to_der(Sbuf, sizeof(Sbuf), out, outlen) != 1) {
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error_print();
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return -1;
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}
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return 1;
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}
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int sm9_signature_from_der(SM9_SIGNATURE *sig, const uint8_t **in, size_t *inlen)
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{
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int ret;
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const uint8_t *d;
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size_t dlen;
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const uint8_t *h;
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size_t hlen;
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const uint8_t *S;
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size_t Slen;
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if ((ret = asn1_sequence_from_der(&d, &dlen, in, inlen)) != 1) {
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if (ret < 0) error_print();
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return ret;
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}
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if (asn1_octet_string_from_der(&h, &hlen, &d, &dlen) != 1
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|| asn1_bit_octets_from_der(&S, &Slen, &d, &dlen) != 1
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|| asn1_check(hlen == 32) != 1
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|| asn1_check(Slen == 65) != 1
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|| asn1_length_is_zero(dlen) != 1) {
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error_print();
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return -1;
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}
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if (sm9_fn_from_bytes(sig->h, h) != 1
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|| sm9_point_from_uncompressed_octets(&sig->S, S) != 1) {
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error_print();
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return -1;
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}
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return 1;
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}
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int sm9_sign_init(SM9_SIGN_CTX *ctx)
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{
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const uint8_t prefix[1] = { SM9_HASH2_PREFIX };
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sm3_init(&ctx->sm3_ctx);
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sm3_update(&ctx->sm3_ctx, prefix, sizeof(prefix));
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return 1;
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}
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int sm9_sign_update(SM9_SIGN_CTX *ctx, const uint8_t *data, size_t datalen)
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{
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sm3_update(&ctx->sm3_ctx, data, datalen);
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return 1;
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}
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int sm9_sign_finish(SM9_SIGN_CTX *ctx, const SM9_SIGN_KEY *key, uint8_t *sig, size_t *siglen)
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{
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SM9_SIGNATURE signature;
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if (sm9_do_sign(key, &ctx->sm3_ctx, &signature) != 1) {
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error_print();
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return -1;
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}
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*siglen = 0;
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if (sm9_signature_to_der(&signature, &sig, siglen) != 1) {
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error_print();
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return -1;
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}
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return 1;
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}
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int sm9_do_sign(const SM9_SIGN_KEY *key, const SM3_CTX *sm3_ctx, SM9_SIGNATURE *sig)
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{
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sm9_fn_t r;
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sm9_fp12_t g;
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uint8_t wbuf[32 * 12];
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SM3_CTX ctx = *sm3_ctx;
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SM3_CTX tmp_ctx;
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uint8_t ct1[4] = {0,0,0,1};
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uint8_t ct2[4] = {0,0,0,2};
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uint8_t Ha[64];
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// A1: g = e(P1, Ppubs)
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sm9_pairing(g, &key->Ppubs, SM9_P1);
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do {
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// A2: rand r in [1, N-1]
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if (sm9_fn_rand(r) != 1) {
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error_print();
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return -1;
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}
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//sm9_fn_from_hex(r, "00033C8616B06704813203DFD00965022ED15975C662337AED648835DC4B1CBE"); // for testing
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// A3: w = g^r
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sm9_fp12_pow(g, g, r);
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sm9_fp12_to_bytes(g, wbuf);
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// A4: h = H2(M || w, N)
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sm3_update(&ctx, wbuf, sizeof(wbuf));
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tmp_ctx = ctx;
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sm3_update(&ctx, ct1, sizeof(ct1));
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sm3_finish(&ctx, Ha);
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sm3_update(&tmp_ctx, ct2, sizeof(ct2));
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sm3_finish(&tmp_ctx, Ha + 32);
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sm9_fn_from_hash(sig->h, Ha);
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// A5: l = (r - h) mod N, if l = 0, goto A2
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sm9_fn_sub(r, r, sig->h);
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} while (sm9_fn_is_zero(r));
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// A6: S = l * dsA
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sm9_point_mul(&sig->S, r, &key->ds);
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gmssl_secure_clear(&r, sizeof(r));
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gmssl_secure_clear(&g, sizeof(g));
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gmssl_secure_clear(wbuf, sizeof(wbuf));
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gmssl_secure_clear(&tmp_ctx, sizeof(tmp_ctx));
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gmssl_secure_clear(Ha, sizeof(Ha));
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return 1;
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}
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int sm9_verify_init(SM9_SIGN_CTX *ctx)
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{
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const uint8_t prefix[1] = { SM9_HASH2_PREFIX };
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sm3_init(&ctx->sm3_ctx);
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sm3_update(&ctx->sm3_ctx, prefix, sizeof(prefix));
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return 1;
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}
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int sm9_verify_update(SM9_SIGN_CTX *ctx, const uint8_t *data, size_t datalen)
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{
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sm3_update(&ctx->sm3_ctx, data, datalen);
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return 1;
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}
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int sm9_verify_finish(SM9_SIGN_CTX *ctx, const uint8_t *sig, size_t siglen,
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const SM9_SIGN_MASTER_KEY *mpk, const char *id, size_t idlen)
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{
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int ret;
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SM9_SIGNATURE signature;
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if (sm9_signature_from_der(&signature, &sig, &siglen) != 1
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|| asn1_length_is_zero(siglen) != 1) {
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error_print();
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return -1;
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}
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if ((ret = sm9_do_verify(mpk, id, idlen, &ctx->sm3_ctx, &signature)) < 0) {
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error_print();
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return -1;
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}
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return ret;
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}
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int sm9_do_verify(const SM9_SIGN_MASTER_KEY *mpk, const char *id, size_t idlen,
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const SM3_CTX *sm3_ctx, const SM9_SIGNATURE *sig)
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{
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sm9_fn_t h1;
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sm9_fn_t h2;
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sm9_fp12_t g;
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sm9_fp12_t t;
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sm9_fp12_t u;
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sm9_fp12_t w;
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SM9_TWIST_POINT P;
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uint8_t wbuf[32 * 12];
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SM3_CTX ctx = *sm3_ctx;
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SM3_CTX tmp_ctx;
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uint8_t ct1[4] = {0,0,0,1};
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uint8_t ct2[4] = {0,0,0,2};
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uint8_t Ha[64];
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// B1: check h in [1, N-1]
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// B2: check S in G1
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// B3: g = e(P1, Ppubs)
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sm9_pairing(g, &mpk->Ppubs, SM9_P1);
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// B4: t = g^h
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sm9_fp12_pow(t, g, sig->h);
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// B5: h1 = H1(ID || hid, N)
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sm9_hash1(h1, id, idlen, SM9_HID_SIGN);
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// B6: P = h1 * P2 + Ppubs
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sm9_twist_point_mul_generator(&P, h1);
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sm9_twist_point_add_full(&P, &P, &mpk->Ppubs);
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// B7: u = e(S, P)
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sm9_pairing(u, &P, &sig->S);
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// B8: w = u * t
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sm9_fp12_mul(w, u, t);
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sm9_fp12_to_bytes(w, wbuf);
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// B9: h2 = H2(M || w, N), check h2 == h
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sm3_update(&ctx, wbuf, sizeof(wbuf));
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tmp_ctx = ctx;
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sm3_update(&ctx, ct1, sizeof(ct1));
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sm3_finish(&ctx, Ha);
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sm3_update(&tmp_ctx, ct2, sizeof(ct2));
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sm3_finish(&tmp_ctx, Ha + 32);
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sm9_fn_from_hash(h2, Ha);
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if (sm9_fn_equ(h2, sig->h) != 1) {
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return 0;
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}
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return 1;
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}
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int sm9_kem_encrypt(const SM9_ENC_MASTER_KEY *mpk, const char *id, size_t idlen,
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size_t klen, uint8_t *kbuf, SM9_POINT *C)
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{
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sm9_fn_t r;
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sm9_fp12_t w;
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uint8_t wbuf[32 * 12];
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uint8_t cbuf[65];
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SM3_KDF_CTX kdf_ctx;
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// A1: Q = H1(ID||hid,N) * P1 + Ppube
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sm9_hash1(r, id, idlen, SM9_HID_ENC);
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sm9_point_mul(C, r, SM9_P1);
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sm9_point_add(C, C, &mpk->Ppube);
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do {
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// A2: rand r in [1, N-1]
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if (sm9_fn_rand(r) != 1) {
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error_print();
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return -1;
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}
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// A3: C1 = r * Q
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sm9_point_mul(C, r, C);
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sm9_point_to_uncompressed_octets(C, cbuf);
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// A4: g = e(Ppube, P2)
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sm9_pairing(w, SM9_P2, &mpk->Ppube);
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// A5: w = g^r
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sm9_fp12_pow(w, w, r);
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sm9_fp12_to_bytes(w, wbuf);
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// A6: K = KDF(C || w || ID_B, klen), if K == 0, goto A2
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sm3_kdf_init(&kdf_ctx, klen);
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sm3_kdf_update(&kdf_ctx, cbuf + 1, 64);
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sm3_kdf_update(&kdf_ctx, wbuf, sizeof(wbuf));
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sm3_kdf_update(&kdf_ctx, (uint8_t *)id, idlen);
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sm3_kdf_finish(&kdf_ctx, kbuf);
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} while (mem_is_zero(kbuf, klen) == 1);
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gmssl_secure_clear(&r, sizeof(r));
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gmssl_secure_clear(&w, sizeof(w));
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gmssl_secure_clear(wbuf, sizeof(wbuf));
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gmssl_secure_clear(&kdf_ctx, sizeof(kdf_ctx));
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// A7: output (K, C)
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return 1;
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}
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int sm9_kem_decrypt(const SM9_ENC_KEY *key, const char *id, size_t idlen, const SM9_POINT *C,
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size_t klen, uint8_t *kbuf)
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{
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sm9_fp12_t w;
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uint8_t wbuf[32 * 12];
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uint8_t cbuf[65];
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SM3_KDF_CTX kdf_ctx;
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// B1: check C in G1
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sm9_point_to_uncompressed_octets(C, cbuf);
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// B2: w = e(C, de);
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sm9_pairing(w, &key->de, C);
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sm9_fp12_to_bytes(w, wbuf);
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// B3: K = KDF(C || w || ID, klen)
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sm3_kdf_init(&kdf_ctx, klen);
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sm3_kdf_update(&kdf_ctx, cbuf + 1, 64);
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sm3_kdf_update(&kdf_ctx, wbuf, sizeof(wbuf));
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sm3_kdf_update(&kdf_ctx, (uint8_t *)id, idlen);
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sm3_kdf_finish(&kdf_ctx, kbuf);
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if (mem_is_zero(kbuf, klen)) {
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error_print();
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return -1;
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}
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gmssl_secure_clear(&w, sizeof(w));
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gmssl_secure_clear(wbuf, sizeof(wbuf));
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gmssl_secure_clear(&kdf_ctx, sizeof(kdf_ctx));
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// B4: output K
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return 1;
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}
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int sm9_do_encrypt(const SM9_ENC_MASTER_KEY *mpk, const char *id, size_t idlen,
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const uint8_t *in, size_t inlen,
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SM9_POINT *C1, uint8_t *c2, uint8_t c3[SM3_HMAC_SIZE])
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{
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SM3_HMAC_CTX hmac_ctx;
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uint8_t K[SM9_MAX_PLAINTEXT_SIZE + 32];
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if (sm9_kem_encrypt(mpk, id, idlen, sizeof(K), K, C1) != 1) {
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error_print();
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return -1;
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}
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gmssl_memxor(c2, K, in, inlen);
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//sm3_hmac(K + inlen, 32, c2, inlen, c3);
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sm3_hmac_init(&hmac_ctx, K + inlen, SM3_HMAC_SIZE);
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sm3_hmac_update(&hmac_ctx, c2, inlen);
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sm3_hmac_finish(&hmac_ctx, c3);
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gmssl_secure_clear(&hmac_ctx, sizeof(hmac_ctx));
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return 1;
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}
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int sm9_do_decrypt(const SM9_ENC_KEY *key, const char *id, size_t idlen,
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const SM9_POINT *C1, const uint8_t *c2, size_t c2len, const uint8_t c3[SM3_HMAC_SIZE],
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uint8_t *out)
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{
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SM3_HMAC_CTX hmac_ctx;
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uint8_t k[SM9_MAX_PLAINTEXT_SIZE + SM3_HMAC_SIZE];
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uint8_t mac[SM3_HMAC_SIZE];
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if (c2len > SM9_MAX_PLAINTEXT_SIZE) {
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error_print();
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return -1;
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}
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if (sm9_kem_decrypt(key, id, idlen, C1, sizeof(k), k) != 1) {
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error_print();
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return -1;
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}
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//sm3_hmac(k + c2len, SM3_HMAC_SIZE, c2, c2len, mac);
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sm3_hmac_init(&hmac_ctx, k + c2len, SM3_HMAC_SIZE);
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sm3_hmac_update(&hmac_ctx, c2, c2len);
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sm3_hmac_finish(&hmac_ctx, mac);
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gmssl_secure_clear(&hmac_ctx, sizeof(hmac_ctx));
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if (gmssl_secure_memcmp(c3, mac, sizeof(mac)) != 0) {
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error_print();
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return -1;
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}
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gmssl_memxor(out, k, c2, c2len);
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return 1;
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}
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#define SM9_ENC_TYPE_XOR 0
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#define SM9_ENC_TYPE_ECB 1
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#define SM9_ENC_TYPE_CBC 2
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#define SM9_ENC_TYPE_OFB 4
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#define SM9_ENC_TYPE_CFB 8
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/*
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SM9Cipher ::= SEQUENCE {
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EnType INTEGER, -- 0 for XOR
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C1 BIT STRING, -- uncompressed octets of ECPoint
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C3 OCTET STRING, -- 32 bytes HMAC-SM3 tag
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CipherText OCTET STRING,
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}
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*/
|
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int sm9_ciphertext_to_der(const SM9_POINT *C1, const uint8_t *c2, size_t c2len,
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const uint8_t c3[SM3_HMAC_SIZE], uint8_t **out, size_t *outlen)
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{
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int en_type = SM9_ENC_TYPE_XOR;
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uint8_t c1[65];
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size_t len = 0;
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if (sm9_point_to_uncompressed_octets(C1, c1) != 1) {
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error_print();
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return -1;
|
||||
}
|
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if (asn1_int_to_der(en_type, NULL, &len) != 1
|
||||
|| asn1_bit_octets_to_der(c1, sizeof(c1), NULL, &len) != 1
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||||
|| asn1_octet_string_to_der(c3, SM3_HMAC_SIZE, NULL, &len) != 1
|
||||
|| asn1_octet_string_to_der(c2, c2len, NULL, &len) != 1
|
||||
|| asn1_sequence_header_to_der(len, out, outlen) != 1
|
||||
|| asn1_int_to_der(en_type, out, outlen) != 1
|
||||
|| asn1_bit_octets_to_der(c1, sizeof(c1), out, outlen) != 1
|
||||
|| asn1_octet_string_to_der(c3, SM3_HMAC_SIZE, out, outlen) != 1
|
||||
|| asn1_octet_string_to_der(c2, c2len, out, outlen) != 1) {
|
||||
error_print();
|
||||
return -1;
|
||||
}
|
||||
return 1;
|
||||
}
|
||||
|
||||
int sm9_ciphertext_from_der(SM9_POINT *C1, const uint8_t **c2, size_t *c2len,
|
||||
const uint8_t **c3, const uint8_t **in, size_t *inlen)
|
||||
{
|
||||
int ret;
|
||||
const uint8_t *d;
|
||||
size_t dlen;
|
||||
int en_type;
|
||||
const uint8_t *c1;
|
||||
size_t c1len;
|
||||
size_t c3len;
|
||||
|
||||
if ((ret = asn1_sequence_from_der(&d, &dlen, in, inlen)) != 1) {
|
||||
if (ret < 0) error_print();
|
||||
return ret;
|
||||
}
|
||||
if (asn1_int_from_der(&en_type, &d, &dlen) != 1
|
||||
|| asn1_bit_octets_from_der(&c1, &c1len, &d, &dlen) != 1
|
||||
|| asn1_octet_string_from_der(c3, &c3len, &d, &dlen) != 1
|
||||
|| asn1_octet_string_from_der(c2, c2len, &d, &dlen) != 1
|
||||
|| asn1_length_is_zero(dlen) != 1) {
|
||||
error_print();
|
||||
return -1;
|
||||
}
|
||||
if (en_type != SM9_ENC_TYPE_XOR) {
|
||||
error_print();
|
||||
return -1;
|
||||
}
|
||||
if (c1len != 65) {
|
||||
error_print();
|
||||
return -1;
|
||||
}
|
||||
if (c3len != SM3_HMAC_SIZE) {
|
||||
error_print();
|
||||
return -1;
|
||||
}
|
||||
if (sm9_point_from_uncompressed_octets(C1, c1) != 1) {
|
||||
error_print();
|
||||
return -1;
|
||||
}
|
||||
return 1;
|
||||
}
|
||||
|
||||
int sm9_encrypt(const SM9_ENC_MASTER_KEY *mpk, const char *id, size_t idlen,
|
||||
const uint8_t *in, size_t inlen, uint8_t *out, size_t *outlen)
|
||||
{
|
||||
SM9_POINT C1;
|
||||
uint8_t c2[SM9_MAX_PLAINTEXT_SIZE];
|
||||
uint8_t c3[SM3_HMAC_SIZE];
|
||||
|
||||
if (inlen > SM9_MAX_PLAINTEXT_SIZE) {
|
||||
error_print();
|
||||
return -1;
|
||||
}
|
||||
|
||||
if (sm9_do_encrypt(mpk, id, idlen, in, inlen, &C1, c2, c3) != 1) {
|
||||
error_print();
|
||||
return -1;
|
||||
}
|
||||
*outlen = 0;
|
||||
if (sm9_ciphertext_to_der(&C1, c2, inlen, c3, &out, outlen) != 1) { // FIXME: when out == NULL
|
||||
error_print();
|
||||
return -1;
|
||||
}
|
||||
return 1;
|
||||
}
|
||||
|
||||
int sm9_decrypt(const SM9_ENC_KEY *key, const char *id, size_t idlen,
|
||||
const uint8_t *in, size_t inlen, uint8_t *out, size_t *outlen)
|
||||
{
|
||||
SM9_POINT C1;
|
||||
const uint8_t *c2;
|
||||
size_t c2len;
|
||||
const uint8_t *c3;
|
||||
|
||||
if (sm9_ciphertext_from_der(&C1, &c2, &c2len, &c3, &in, &inlen) != 1
|
||||
|| asn1_length_is_zero(inlen) != 1) {
|
||||
error_print();
|
||||
return -1;
|
||||
}
|
||||
*outlen = c2len;
|
||||
if (!out) {
|
||||
return 1;
|
||||
}
|
||||
if (sm9_do_decrypt(key, id, idlen, &C1, c2, c2len, c3, out) != 1) {
|
||||
error_print();
|
||||
return -1;
|
||||
}
|
||||
return 1;
|
||||
}
|
||||
Reference in New Issue
Block a user