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openssl3.2 - 官方demo学习 - signature - EVP_DSA_Signature_demo.c

概述

DSA签名(摘要算法SHA256), DSA验签(摘要算法SHA256)
签名 : 用发送者的私钥进行签名.
验签 : 用发送者的公钥进行验签.

看下API调用顺序就行, 自己弄的时候, 跟着demo的流程弄就行.
对于openssl3.2, 越看越眼熟了.

笔记

/*!
\file EVP_DSA_Signature_demo.c
\note 
openssl3.2 - 官方demo学习 - signature - EVP_DSA_Signature_demo.cDSA签名(摘要算法SHA256), DSA验签(摘要算法SHA256)
签名 : 用发送者的私钥进行签名.
验签 : 用发送者的公钥进行验签.看下API调用顺序就行, 自己弄的时候, 跟着demo的流程弄就行.
对于openssl3.2, 越看越眼熟了.
*//*-* Copyright 2022-2023 The OpenSSL Project Authors. All Rights Reserved.** Licensed under the Apache License 2.0 (the "License").  You may not use* this file except in compliance with the License.  You can obtain a copy* in the file LICENSE in the source distribution or at* https://www.openssl.org/source/license.html*//** An example that uses the EVP_PKEY*, EVP_DigestSign* and EVP_DigestVerify** methods to calculate public/private DSA keypair and to sign and verify* two static buffers.*/#include <string.h>
#include <stdio.h>
#include <openssl/err.h>
#include <openssl/evp.h>
#include <openssl/decoder.h>
#include <openssl/dsa.h>#include "my_openSSL_lib.h"/** This demonstration will calculate and verify a signature of data using* the soliloquy from Hamlet scene 1 act 3*/static const char *hamlet_1 ="To be, or not to be, that is the question,\n""Whether tis nobler in the minde to suffer\n""The slings and arrowes of outragious fortune,\n""Or to take Armes again in a sea of troubles,\n"
;
static const char *hamlet_2 ="And by opposing, end them, to die to sleep;\n""No more, and by a sleep, to say we end\n""The heart-ache, and the thousand natural shocks\n""That flesh is heir to? tis a consumation\n"
;static const char ALG[] = "DSA";
static const char DIGEST[] = "SHA256";
static const int NUMBITS = 2048;
static const char * const PROPQUERY = NULL;static int generate_dsa_params(OSSL_LIB_CTX *libctx,EVP_PKEY **p_params)
{int ret = 0;EVP_PKEY_CTX *pkey_ctx = NULL;EVP_PKEY *params = NULL;pkey_ctx = EVP_PKEY_CTX_new_from_name(libctx, ALG, PROPQUERY);if (pkey_ctx == NULL)goto end;if (EVP_PKEY_paramgen_init(pkey_ctx) <= 0)goto end;if (EVP_PKEY_CTX_set_dsa_paramgen_bits(pkey_ctx, NUMBITS) <= 0)goto end;if (EVP_PKEY_paramgen(pkey_ctx, &params) <= 0)goto end;if (params == NULL)goto end;ret = 1;
end:if(ret != 1) {EVP_PKEY_free(params);params = NULL;}EVP_PKEY_CTX_free(pkey_ctx);*p_params = params;fprintf(stdout, "Params:\n");EVP_PKEY_print_params_fp(stdout, params, 4, NULL);fprintf(stdout, "\n");return ret;
}static int generate_dsa_key(OSSL_LIB_CTX *libctx,EVP_PKEY *params,EVP_PKEY **p_pkey)
{int ret = 0;EVP_PKEY_CTX *ctx = NULL;EVP_PKEY *pkey = NULL;ctx = EVP_PKEY_CTX_new_from_pkey(libctx, params,NULL);if (ctx == NULL)goto end;if (EVP_PKEY_keygen_init(ctx) <= 0)goto end;if (EVP_PKEY_keygen(ctx, &pkey) <= 0)goto end;if (pkey == NULL)goto end;ret = 1;
end:if(ret != 1) {EVP_PKEY_free(pkey);pkey = NULL;}EVP_PKEY_CTX_free(ctx);*p_pkey = pkey;fprintf(stdout, "Generating public/private key pair:\n");EVP_PKEY_print_public_fp(stdout, pkey, 4, NULL);fprintf(stdout, "\n");EVP_PKEY_print_private_fp(stdout, pkey, 4, NULL);fprintf(stdout, "\n");EVP_PKEY_print_params_fp(stdout, pkey, 4, NULL);fprintf(stdout, "\n");return ret;
}static int extract_public_key(const EVP_PKEY *pkey,OSSL_PARAM **p_public_key)
{int ret = 0;OSSL_PARAM *public_key = NULL;if (EVP_PKEY_todata(pkey, EVP_PKEY_PUBLIC_KEY, &public_key) != 1)goto end;ret = 1;
end:if (ret != 1) {OSSL_PARAM_free(public_key);public_key = NULL;}*p_public_key = public_key;return ret;
}static int extract_keypair(const EVP_PKEY *pkey,OSSL_PARAM **p_keypair)
{int ret = 0;OSSL_PARAM *keypair = NULL;if (EVP_PKEY_todata(pkey, EVP_PKEY_KEYPAIR, &keypair) != 1)goto end;ret = 1;
end:if (ret != 1) {OSSL_PARAM_free(keypair);keypair = NULL;}*p_keypair = keypair;return ret;
}static int demo_sign(OSSL_LIB_CTX *libctx,size_t *p_sig_len, unsigned char **p_sig_value,OSSL_PARAM keypair[])
{int ret = 0;size_t sig_len = 0;unsigned char *sig_value = NULL;EVP_MD_CTX *ctx = NULL;EVP_PKEY_CTX *pkey_ctx = NULL;EVP_PKEY *pkey = NULL;pkey_ctx = EVP_PKEY_CTX_new_from_name(libctx, ALG, PROPQUERY);if (pkey_ctx == NULL)goto end;if (EVP_PKEY_fromdata_init(pkey_ctx) != 1)goto end;if (EVP_PKEY_fromdata(pkey_ctx, &pkey, EVP_PKEY_KEYPAIR, keypair) != 1)goto end;ctx = EVP_MD_CTX_create();if (ctx == NULL)goto end;if (EVP_DigestSignInit_ex(ctx, NULL, DIGEST, libctx, NULL, pkey, NULL) != 1)goto end;if (EVP_DigestSignUpdate(ctx, hamlet_1, sizeof(hamlet_1)) != 1)goto end;if (EVP_DigestSignUpdate(ctx, hamlet_2, sizeof(hamlet_2)) != 1)goto end;/* Calculate the signature size */if (EVP_DigestSignFinal(ctx, NULL, &sig_len) != 1)goto end;if (sig_len == 0)goto end;sig_value = OPENSSL_malloc(sig_len);if (sig_value == NULL)goto end;/* Calculate the signature */if (EVP_DigestSignFinal(ctx, sig_value, &sig_len) != 1)goto end;ret = 1;
end:EVP_MD_CTX_free(ctx);if (ret != 1) {OPENSSL_free(sig_value);sig_len = 0;sig_value = NULL;}*p_sig_len = sig_len;*p_sig_value = sig_value;EVP_PKEY_free(pkey);EVP_PKEY_CTX_free(pkey_ctx);fprintf(stdout, "Generating signature:\n");BIO_dump_indent_fp(stdout, sig_value, (int)sig_len, 2);fprintf(stdout, "\n");return ret;
}static int demo_verify(OSSL_LIB_CTX *libctx,size_t sig_len, unsigned char *sig_value,OSSL_PARAM public_key[])
{int ret = 0;EVP_MD_CTX *ctx = NULL;EVP_PKEY_CTX *pkey_ctx = NULL;EVP_PKEY *pkey = NULL;pkey_ctx = EVP_PKEY_CTX_new_from_name(libctx, ALG, PROPQUERY);if (pkey_ctx == NULL)goto end;if (EVP_PKEY_fromdata_init(pkey_ctx) != 1)goto end;if (EVP_PKEY_fromdata(pkey_ctx, &pkey, EVP_PKEY_PUBLIC_KEY, public_key) != 1)goto end;ctx = EVP_MD_CTX_create();if(ctx == NULL)goto end;if (EVP_DigestVerifyInit_ex(ctx, NULL, DIGEST, libctx, NULL, pkey, NULL) != 1)goto end;if (EVP_DigestVerifyUpdate(ctx, hamlet_1, sizeof(hamlet_1)) != 1)goto end;if (EVP_DigestVerifyUpdate(ctx, hamlet_2, sizeof(hamlet_2)) != 1)goto end;if (EVP_DigestVerifyFinal(ctx, sig_value, sig_len) != 1)goto end;ret = 1;
end:EVP_PKEY_free(pkey);EVP_PKEY_CTX_free(pkey_ctx);EVP_MD_CTX_free(ctx);return ret;
}int main(void)
{int ret = EXIT_FAILURE;OSSL_LIB_CTX *libctx = NULL;EVP_PKEY *params = NULL;EVP_PKEY *pkey = NULL;OSSL_PARAM *public_key = NULL;OSSL_PARAM *keypair = NULL;size_t sig_len = 0;unsigned char *sig_value = NULL;libctx = OSSL_LIB_CTX_new();if (libctx == NULL)goto end;if (generate_dsa_params(libctx, &params) != 1)goto end;if (generate_dsa_key(libctx, params, &pkey) != 1)goto end;if (extract_public_key(pkey, &public_key) != 1)goto end;if (extract_keypair(pkey, &keypair) != 1)goto end;/* The signer signs with his private key, and distributes his public key */if (demo_sign(libctx, &sig_len, &sig_value, keypair) != 1)goto end;/* A verifier uses the signers public key to verify the signature */if (demo_verify(libctx, sig_len, sig_value, public_key) != 1)goto end;ret = EXIT_SUCCESS;
end:if (ret != EXIT_SUCCESS)ERR_print_errors_fp(stderr);OPENSSL_free(sig_value);EVP_PKEY_free(params);EVP_PKEY_free(pkey);OSSL_PARAM_free(public_key);OSSL_PARAM_free(keypair);OSSL_LIB_CTX_free(libctx);return ret;
}

END