TLS/SSL

SSL/TLS 双向认证(一) -- SSL/TLS 工作原理 本文部分参考: https://www.wosign.com/faq/faq2016-0309-03.htm https://www.wosign.com/faq/faq2016-0309-04.htm http://blog.youkuaiyun.com/hherima/article/details/52469674 一: SSL/TLS介绍 什么是SSL,什么是TLS呢?官话说SSL是安全套... 阅读详情

SSL(Secure Socket Layer)是网景(Netscape)公司研发的用于保证数据在socket层(应用层)传输的安全性。

TLS(Transport Layer Security)是在SSL3.0基础上形成的一种标准协议规范。

TLS通过非对称加密算法,数字证书,CA等完成身份认证;同时通过rsa或dh(ecdh)算法协商对称密钥;采用对称密钥加密通信数据;确保数据的机密性、完整性。

通过sessionid记录协商信息,下次连接带上sessionid可跳过耗时的协商过程。

协议交换流程

 (图片来自透视Http协议课程)

5字节的ssl协议头(类型+版本+长度)

==>   ClientHello//支持的tls版本、加密算法,随机数

<==   ServerHello//确认tls版本、加密算法,随机数
       Certificate//服务端证书
      ( ServerKeyExchange  )//通过rsa或dh(ecdh)算法协商密钥
      ( CertificateRequest )//要求客户端提供证书
      ServerHelloDone

==> ( Certificate/Alert  )//客户端证书
     ClientKeyExchange//通过rsa或dh算法协商密钥
    ( CertificateVerify  )//校验服务端证书
    ChangeCipherSpec//告知对方从现在开始发送的消息都是加密过的
     Finished

<==   ChangeCipherSpec//告知对方从现在开始发送的消息都是加密过的
       Finished

抓包流程

开源库

https://www.openssl.org/
https://tls.mbed.org/

代码示例

基于mbedtls库的代码示例

client demo code    

/*
 *  SSL client with certificate authentication
 *
 *  Copyright (C) 2006-2010, Brainspark B.V.
 *
 *  This file is part of PolarSSL (http://www.polarssl.org)
 *  Lead Maintainer: Paul Bakker <polarssl_maintainer at polarssl.org>
 *
 *  All rights reserved.
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License along
 *  with this program; if not, write to the Free Software Foundation, Inc.,
 *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#ifndef _CRT_SECURE_NO_DEPRECATE
#define _CRT_SECURE_NO_DEPRECATE 1
#endif

#include <string.h>
#include <stdlib.h>
#include <stdio.h>

#include "polarssl/config.h"

#include "polarssl/net.h"
#include "polarssl/ssl.h"
#include "polarssl/havege.h"
#include "polarssl/certs.h"
#include "polarssl/x509.h"

#define DFL_SERVER_NAME         "localhost"
#define DFL_SERVER_PORT         4433
#define DFL_REQUEST_PAGE        "/"
#define DFL_DEBUG_LEVEL         0
#define DFL_CA_FILE             ""
#define DFL_CRT_FILE            ""
#define DFL_KEY_FILE            ""
#define DFL_FORCE_CIPHER        0

#define GET_REQUEST "GET %s HTTP/1.0\r\n\r\n"

/*
 * global options
 */
struct options
{
    char *server_name;          /* hostname of the server (client only)     */
    int server_port;            /* port on which the ssl service runs       */
    int debug_level;            /* level of debugging                       */
    char *request_page;         /* page on server to request                */
    char *ca_file;              /* the file with the CA certificate(s)      */
    char *crt_file;             /* the file with the client certificate     */
    char *key_file;             /* the file with the client key             */
    int force_ciphersuite[2];   /* protocol/ciphersuite to use, or all      */
} opt;

void my_debug( void *ctx, int level, const char *str )
{
    if( level < opt.debug_level )
    {
        fprintf( (FILE *) ctx, "%s", str );
        fflush(  (FILE *) ctx  );
    }
}

#if defined(POLARSSL_FS_IO)
#define USAGE_IO \
    "    ca_file=%%s          default: \"\" (pre-loaded)\n" \
    "    crt_file=%%s         default: \"\" (pre-loaded)\n" \
    "    key_file=%%s         default: \"\" (pre-loaded)\n"
#else
#define USAGE_IO \
    "    No file operations available (POLARSSL_FS_IO not defined)\n"
#endif /* POLARSSL_FS_IO */

#define USAGE \
    "\n usage: ssl_client2 param=<>...\n"                   \
    "\n acceptable parameters:\n"                           \
    "    server_name=%%s      default: localhost\n"         \
    "    server_port=%%d      default: 4433\n"              \
    "    debug_level=%%d      default: 0 (disabled)\n"      \
    USAGE_IO                                                \
    "    request_page=%%s     default: \".\"\n"             \
    "    force_ciphersuite=<name>    default: all enabled\n"\
    " acceptable ciphersuite names:\n"

#if !defined(POLARSSL_BIGNUM_C) || !defined(POLARSSL_HAVEGE_C) ||   \
    !defined(POLARSSL_SSL_TLS_C) || !defined(POLARSSL_SSL_CLI_C) || \
    !defined(POLARSSL_NET_C) || !defined(POLARSSL_RSA_C)
int main( void )
{
    printf("POLARSSL_BIGNUM_C and/or POLARSSL_HAVEGE_C and/or "
           "POLARSSL_SSL_TLS_C and/or POLARSSL_SSL_CLI_C and/or "
           "POLARSSL_NET_C and/or POLARSSL_RSA_C not defined.\n");
    return( 0 );
}
#else
int main( int argc, char *argv[] )
{
    int ret = 0, len, server_fd;
    unsigned char buf[1024];
    havege_state hs;
    ssl_context ssl;
    ssl_session ssn;
    x509_cert cacert;
    x509_cert clicert;
    rsa_context rsa;
    int i;
    size_t j, n;
    char *p, *q;
    const int *list;

    /*
     * Make sure memory references are valid.
     */
    server_fd = 0;
    memset( &ssn, 0, sizeof( ssl_session ) );
    memset( &ssl, 0, sizeof( ssl_context ) );
    memset( &cacert, 0, sizeof( x509_cert ) );
    memset( &clicert, 0, sizeof( x509_cert ) );
    memset( &rsa, 0, sizeof( rsa_context ) );

    if( argc == 0 )
    {
    usage:
        printf( USAGE );

        list = ssl_list_ciphersuites();
        while( *list )
        {
            printf("    %s\n", ssl_get_ciphersuite_name( *list ) );
            list++;
        }
        printf("\n");
        goto exit;
    }

    opt.server_name         = DFL_SERVER_NAME;
    opt.server_port         = DFL_SERVER_PORT;
    opt.debug_level         = DFL_DEBUG_LEVEL;
    opt.request_page        = DFL_REQUEST_PAGE;
    opt.ca_file             = DFL_CA_FILE;
    opt.crt_file            = DFL_CRT_FILE;
    opt.key_file            = DFL_KEY_FILE;
    opt.force_ciphersuite[0]= DFL_FORCE_CIPHER;

    for( i = 1; i < argc; i++ )
    {
        n = strlen( argv[i] );

        for( j = 0; j < n; j++ )
        {
            if( argv[i][j] >= 'A' && argv[i][j] <= 'Z' )
                argv[i][j] |= 0x20;
        }

        p = argv[i];
        if( ( q = strchr( p, '=' ) ) == NULL )
            goto usage;
        *q++ = '\0';

        if( strcmp( p, "server_name" ) == 0 )
            opt.server_name = q;
        else if( strcmp( p, "server_port" ) == 0 )
        {
            opt.server_port = atoi( q );
            if( opt.server_port < 1 || opt.server_port > 65535 )
                goto usage;
        }
        else if( strcmp( p, "debug_level" ) == 0 )
        {
            opt.debug_level = atoi( q );
            if( opt.debug_level < 0 || opt.debug_level > 65535 )
                goto usage;
        }
        else if( strcmp( p, "request_page" ) == 0 )
            opt.request_page = q;
        else if( strcmp( p, "ca_file" ) == 0 )
            opt.ca_file = q;
        else if( strcmp( p, "crt_file" ) == 0 )
            opt.crt_file = q;
        else if( strcmp( p, "key_file" ) == 0 )
            opt.key_file = q;
        else if( strcmp( p, "force_ciphersuite" ) == 0 )
        {
            opt.force_ciphersuite[0] = -1;

            opt.force_ciphersuite[0] = ssl_get_ciphersuite_id( q );

            if( opt.force_ciphersuite[0] <= 0 )
                goto usage;

            opt.force_ciphersuite[1] = 0;
        }
        else
            goto usage;
    }

    /*
     * 0. Initialize the RNG and the session data
     */
    havege_init( &hs );

    /*
     * 1.1. Load the trusted CA
     */
    printf( "\n  . Loading the CA root certificate ..." );
    fflush( stdout );

#if defined(POLARSSL_FS_IO)
    if( strlen( opt.ca_file ) )
        ret = x509parse_crtfile( &cacert, opt.ca_file );
    else 
#endif
#if defined(POLARSSL_CERTS_C)
        ret = x509parse_crt( &cacert, (unsigned char *) test_ca_crt,
                strlen( test_ca_crt ) );
#else
    {
        ret = 1;
        printf("POLARSSL_CERTS_C not defined.");
    }
#endif
    if( ret != 0 )
    {
        printf( " failed\n  !  x509parse_crt returned %d\n\n", ret );
        goto exit;
    }

    printf( " ok\n" );

    /*
     * 1.2. Load own certificate and private key
     *
     * (can be skipped if client authentication is not required)
     */
    printf( "  . Loading the client cert. and key..." );
    fflush( stdout );

#if defined(POLARSSL_FS_IO)
    if( strlen( opt.crt_file ) )
        ret = x509parse_crtfile( &clicert, opt.crt_file );
    else 
#endif
#if defined(POLARSSL_CERTS_C)
        ret = x509parse_crt( &clicert, (unsigned char *) test_cli_crt,
                strlen( test_cli_crt ) );
#else
    {
        ret = 1;
        printf("POLARSSL_CERTS_C not defined.");
    }
#endif
    if( ret != 0 )
    {
        printf( " failed\n  !  x509parse_crt returned %d\n\n", ret );
        goto exit;
    }

#if defined(POLARSSL_FS_IO)
    if( strlen( opt.key_file ) )
        ret = x509parse_keyfile( &rsa, opt.key_file, "" );
    else
#endif
#if defined(POLARSSL_CERTS_C)
        ret = x509parse_key( &rsa, (unsigned char *) test_cli_key,
                strlen( test_cli_key ), NULL, 0 );
#else
    {
        ret = 1;
        printf("POLARSSL_CERTS_C not defined.");
    }
#endif
    if( ret != 0 )
    {
        printf( " failed\n  !  x509parse_key returned %d\n\n", ret );
        goto exit;
    }

    printf( " ok\n" );

    /*
     * 2. Start the connection
     */
    printf( "  . Connecting to tcp/%s/%-4d...", opt.server_name,
                                                opt.server_port );
    fflush( stdout );

    if( ( ret = net_connect( &server_fd, opt.server_name,
                                         opt.server_port ) ) != 0 )
    {
        printf( " failed\n  ! net_connect returned %d\n\n", ret );
        goto exit;
    }

    printf( " ok\n" );

    /*
     * 3. Setup stuff
     */
    printf( "  . Setting up the SSL/TLS structure..." );
    fflush( stdout );

    havege_init( &hs );

    if( ( ret = ssl_init( &ssl ) ) != 0 )
    {
        printf( " failed\n  ! ssl_init returned %d\n\n", ret );
        goto exit;
    }

    printf( " ok\n" );

    ssl_set_endpoint( &ssl, SSL_IS_CLIENT );
    ssl_set_authmode( &ssl, SSL_VERIFY_OPTIONAL );

    ssl_set_rng( &ssl, havege_rand, &hs );
    ssl_set_dbg( &ssl, my_debug, stdout );
    ssl_set_bio( &ssl, net_recv, &server_fd,
                       net_send, &server_fd );

    if( opt.force_ciphersuite[0] == DFL_FORCE_CIPHER )
        ssl_set_ciphersuites( &ssl, ssl_default_ciphersuites );
    else
        ssl_set_ciphersuites( &ssl, opt.force_ciphersuite );

    ssl_set_session( &ssl, 1, 600, &ssn );

    ssl_set_ca_chain( &ssl, &cacert, NULL, opt.server_name );
    ssl_set_own_cert( &ssl, &clicert, &rsa );

    ssl_set_hostname( &ssl, opt.server_name );

    /*
     * 4. Handshake
     */
    printf( "  . Performing the SSL/TLS handshake..." );
    fflush( stdout );

    while( ( ret = ssl_handshake( &ssl ) ) != 0 )
    {
        if( ret != POLARSSL_ERR_NET_WANT_READ && ret != POLARSSL_ERR_NET_WANT_WRITE )
        {
            printf( " failed\n  ! ssl_handshake returned %d\n\n", ret );
            goto exit;
        }
    }

    printf( " ok\n    [ Ciphersuite is %s ]\n",
            ssl_get_ciphersuite( &ssl ) );

    /*
     * 5. Verify the server certificate
     */
    printf( "  . Verifying peer X.509 certificate..." );

    if( ( ret = ssl_get_verify_result( &ssl ) ) != 0 )
    {
        printf( " failed\n" );

        if( ( ret & BADCERT_EXPIRED ) != 0 )
            printf( "  ! server certificate has expired\n" );

        if( ( ret & BADCERT_REVOKED ) != 0 )
            printf( "  ! server certificate has been revoked\n" );

        if( ( ret & BADCERT_CN_MISMATCH ) != 0 )
            printf( "  ! CN mismatch (expected CN=%s)\n", opt.server_name );

        if( ( ret & BADCERT_NOT_TRUSTED ) != 0 )
            printf( "  ! self-signed or not signed by a trusted CA\n" );

        printf( "\n" );
    }
    else
        printf( " ok\n" );

    printf( "  . Peer certificate information    ...\n" );
    x509parse_cert_info( (char *) buf, sizeof( buf ) - 1, "      ", ssl.peer_cert );
    printf( "%s\n", buf );

    /*
     * 6. Write the GET request
     */
    printf( "  > Write to server:" );
    fflush( stdout );

    len = sprintf( (char *) buf, GET_REQUEST, opt.request_page );

    while( ( ret = ssl_write( &ssl, buf, len ) ) <= 0 )
    {
        if( ret != POLARSSL_ERR_NET_WANT_READ && ret != POLARSSL_ERR_NET_WANT_WRITE )
        {
            printf( " failed\n  ! ssl_write returned %d\n\n", ret );
            goto exit;
        }
    }

    len = ret;
    printf( " %d bytes written\n\n%s", len, (char *) buf );

    /*
     * 7. Read the HTTP response
     */
    printf( "  < Read from server:" );
    fflush( stdout );

    do
    {
        len = sizeof( buf ) - 1;
        memset( buf, 0, sizeof( buf ) );
        ret = ssl_read( &ssl, buf, len );

        if( ret == POLARSSL_ERR_NET_WANT_READ || ret == POLARSSL_ERR_NET_WANT_WRITE )
            continue;

        if( ret == POLARSSL_ERR_SSL_PEER_CLOSE_NOTIFY )
            break;

        if( ret < 0 )
        {
            printf( "failed\n  ! ssl_read returned %d\n\n", ret );
            break;
        }

        if( ret == 0 )
        {
            printf("\n\nEOF\n\n");
            break;
        }

        len = ret;
        printf( " %d bytes read\n\n%s", len, (char *) buf );
    }
    while( 1 );

    ssl_close_notify( &ssl );

exit:

    if( server_fd )
        net_close( server_fd );
    x509_free( &clicert );
    x509_free( &cacert );
    rsa_free( &rsa );
    ssl_free( &ssl );

    memset( &ssl, 0, sizeof( ssl ) );

#ifdef WIN32
    printf( "  + Press Enter to exit this program.\n" );
    fflush( stdout ); getchar();
#endif

    return( ret );
}
#endif /* POLARSSL_BIGNUM_C && POLARSSL_HAVEGE_C && POLARSSL_SSL_TLS_C &&
          POLARSSL_SSL_CLI_C && POLARSSL_NET_C && POLARSSL_RSA_C */

server demo code    

/*
 *  SSL server demonstration program
 *
 *  Copyright (C) 2006-2010, Brainspark B.V.
 *
 *  This file is part of PolarSSL (http://www.polarssl.org)
 *  Lead Maintainer: Paul Bakker <polarssl_maintainer at polarssl.org>
 *
 *  All rights reserved.
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License along
 *  with this program; if not, write to the Free Software Foundation, Inc.,
 *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#ifndef _CRT_SECURE_NO_DEPRECATE
#define _CRT_SECURE_NO_DEPRECATE 1
#endif

#ifdef WIN32
#include <windows.h>
#endif

#include <string.h>
#include <stdlib.h>
#include <stdio.h>

#include "polarssl/config.h"

#include "polarssl/havege.h"
#include "polarssl/certs.h"
#include "polarssl/x509.h"
#include "polarssl/ssl.h"
#include "polarssl/net.h"

#define HTTP_RESPONSE \
    "HTTP/1.0 200 OK\r\nContent-Type: text/html\r\n\r\n" \
    "<h2>PolarSSL Test Server</h2>\r\n" \
    "<p>Successful connection using: %s</p>\r\n"

/*
 * Computing a "safe" DH-1024 prime can take a very
 * long time, so a precomputed value is provided below.
 * You may run dh_genprime to generate a new value.
 */
char *my_dhm_P = 
    "E4004C1F94182000103D883A448B3F80" \
    "2CE4B44A83301270002C20D0321CFD00" \
    "11CCEF784C26A400F43DFB901BCA7538" \
    "F2C6B176001CF5A0FD16D2C48B1D0C1C" \
    "F6AC8E1DA6BCC3B4E1F96B0564965300" \
    "FFA1D0B601EB2800F489AA512C4B248C" \
    "01F76949A60BB7F00A40B1EAB64BDD48" \
    "E8A700D60B7F1200FA8E77B0A979DABF";

char *my_dhm_G = "4";

/*
 * Sorted by order of preference
 */
int my_ciphersuites[] =
{
    SSL_EDH_RSA_AES_256_SHA,
    SSL_EDH_RSA_CAMELLIA_256_SHA,
    SSL_EDH_RSA_AES_128_SHA,
    SSL_EDH_RSA_CAMELLIA_128_SHA,
    SSL_EDH_RSA_DES_168_SHA,
    SSL_RSA_AES_256_SHA,
    SSL_RSA_CAMELLIA_256_SHA,
    SSL_RSA_AES_128_SHA,
    SSL_RSA_CAMELLIA_128_SHA,
    SSL_RSA_DES_168_SHA,
    SSL_RSA_RC4_128_SHA,
    SSL_RSA_RC4_128_MD5,
    0
};

#define DEBUG_LEVEL 0

void my_debug( void *ctx, int level, const char *str )
{
    if( level < DEBUG_LEVEL )
    {
        fprintf( (FILE *) ctx, "%s", str );
        fflush(  (FILE *) ctx  );
    }
}

/*
 * These session callbacks use a simple chained list
 * to store and retrieve the session information.
 */
ssl_session *s_list_1st = NULL;
ssl_session *cur, *prv;

static int my_get_session( ssl_context *ssl )
{
    time_t t = time( NULL );

    if( ssl->resume == 0 )
        return( 1 );

    cur = s_list_1st;
    prv = NULL;

    while( cur != NULL )
    {
        prv = cur;
        cur = cur->next;

        if( ssl->timeout != 0 && t - prv->start > ssl->timeout )
            continue;

        if( ssl->session->ciphersuite != prv->ciphersuite ||
            ssl->session->length != prv->length )
            continue;

        if( memcmp( ssl->session->id, prv->id, prv->length ) != 0 )
            continue;

        memcpy( ssl->session->master, prv->master, 48 );
        return( 0 );
    }

    return( 1 );
}

static int my_set_session( ssl_context *ssl )
{
    time_t t = time( NULL );

    cur = s_list_1st;
    prv = NULL;

    while( cur != NULL )
    {
        if( ssl->timeout != 0 && t - cur->start > ssl->timeout )
            break; /* expired, reuse this slot */

        if( memcmp( ssl->session->id, cur->id, cur->length ) == 0 )
            break; /* client reconnected */

        prv = cur;
        cur = cur->next;
    }

    if( cur == NULL )
    {
        cur = (ssl_session *) malloc( sizeof( ssl_session ) );
        if( cur == NULL )
            return( 1 );

        if( prv == NULL )
              s_list_1st = cur;
        else  prv->next  = cur;
    }

    memcpy( cur, ssl->session, sizeof( ssl_session ) );

    return( 0 );
}

#if !defined(POLARSSL_BIGNUM_C) || !defined(POLARSSL_CERTS_C) ||    \
    !defined(POLARSSL_HAVEGE_C) || !defined(POLARSSL_SSL_TLS_C) ||  \
    !defined(POLARSSL_SSL_SRV_C) || !defined(POLARSSL_NET_C) ||   \
    !defined(POLARSSL_RSA_C)
int main( void )
{
    printf("POLARSSL_BIGNUM_C and/or POLARSSL_CERTS_C and/or POLARSSL_HAVEGE_C "
           "and/or POLARSSL_SSL_TLS_C and/or POLARSSL_SSL_SRV_C and/or "
           "POLARSSL_NET_C and/or POLARSSL_RSA_C not defined.\n");
    return( 0 );
}
#else
int main( void )
{
    int ret, len;
    int listen_fd;
    int client_fd;
    unsigned char buf[1024];

    havege_state hs;
    ssl_context ssl;
    ssl_session ssn;
    x509_cert srvcert;
    rsa_context rsa;

    /*
     * 1. Load the certificates and private RSA key
     */
    printf( "\n  . Loading the server cert. and key..." );
    fflush( stdout );

    memset( &srvcert, 0, sizeof( x509_cert ) );

    /*
     * This demonstration program uses embedded test certificates.
     * Instead, you may want to use x509parse_crtfile() to read the
     * server and CA certificates, as well as x509parse_keyfile().
     */
    ret = x509parse_crt( &srvcert, (unsigned char *) test_srv_crt,
                         strlen( test_srv_crt ) );
    if( ret != 0 )
    {
        printf( " failed\n  !  x509parse_crt returned %d\n\n", ret );
        goto exit;
    }

    ret = x509parse_crt( &srvcert, (unsigned char *) test_ca_crt,
                         strlen( test_ca_crt ) );
    if( ret != 0 )
    {
        printf( " failed\n  !  x509parse_crt returned %d\n\n", ret );
        goto exit;
    }

    rsa_init( &rsa, RSA_PKCS_V15, 0 );
    ret =  x509parse_key( &rsa, (unsigned char *) test_srv_key,
                          strlen( test_srv_key ), NULL, 0 );
    if( ret != 0 )
    {
        printf( " failed\n  !  x509parse_key returned %d\n\n", ret );
        goto exit;
    }

    printf( " ok\n" );

    /*
     * 2. Setup the listening TCP socket
     */
    printf( "  . Bind on https://localhost:4433/ ..." );
    fflush( stdout );

    if( ( ret = net_bind( &listen_fd, NULL, 4433 ) ) != 0 )
    {
        printf( " failed\n  ! net_bind returned %d\n\n", ret );
        goto exit;
    }

    printf( " ok\n" );

    /*
     * 3. Wait until a client connects
     */
#ifdef WIN32
    ShellExecute( NULL, "open", "https://localhost:4433/",
                  NULL, NULL, SW_SHOWNORMAL );
#endif

    client_fd = -1;
    memset( &ssl, 0, sizeof( ssl ) );

accept:

    net_close( client_fd );
    ssl_free( &ssl );

    printf( "  . Waiting for a remote connection ..." );
    fflush( stdout );

    if( ( ret = net_accept( listen_fd, &client_fd, NULL ) ) != 0 )
    {
        printf( " failed\n  ! net_accept returned %d\n\n", ret );
        goto exit;
    }

    printf( " ok\n" );

    /*
     * 4. Setup stuff
     */
    printf( "  . Setting up the RNG and SSL data...." );
    fflush( stdout );

    havege_init( &hs );

    if( ( ret = ssl_init( &ssl ) ) != 0 )
    {
        printf( " failed\n  ! ssl_init returned %d\n\n", ret );
        goto accept;
    }

    printf( " ok\n" );

    ssl_set_endpoint( &ssl, SSL_IS_SERVER );
    ssl_set_authmode( &ssl, SSL_VERIFY_NONE );

    ssl_set_rng( &ssl, havege_rand, &hs );
    ssl_set_dbg( &ssl, my_debug, stdout );
    ssl_set_bio( &ssl, net_recv, &client_fd,
                       net_send, &client_fd );
    ssl_set_scb( &ssl, my_get_session,
                       my_set_session );

    ssl_set_ciphersuites( &ssl, my_ciphersuites );
    ssl_set_session( &ssl, 1, 0, &ssn );

    memset( &ssn, 0, sizeof( ssl_session ) );

    ssl_set_ca_chain( &ssl, srvcert.next, NULL, NULL );
    ssl_set_own_cert( &ssl, &srvcert, &rsa );
    ssl_set_dh_param( &ssl, my_dhm_P, my_dhm_G );

    /*
     * 5. Handshake
     */
    printf( "  . Performing the SSL/TLS handshake..." );
    fflush( stdout );

    while( ( ret = ssl_handshake( &ssl ) ) != 0 )
    {
        if( ret != POLARSSL_ERR_NET_WANT_READ && ret != POLARSSL_ERR_NET_WANT_WRITE )
        {
            printf( " failed\n  ! ssl_handshake returned %d\n\n", ret );
            goto accept;
        }
    }

    printf( " ok\n" );

    /*
     * 6. Read the HTTP Request
     */
    printf( "  < Read from client:" );
    fflush( stdout );

    do
    {
        len = sizeof( buf ) - 1;
        memset( buf, 0, sizeof( buf ) );
        ret = ssl_read( &ssl, buf, len );

        if( ret == POLARSSL_ERR_NET_WANT_READ || ret == POLARSSL_ERR_NET_WANT_WRITE )
            continue;

        if( ret <= 0 )
        {
            switch( ret )
            {
                case POLARSSL_ERR_SSL_PEER_CLOSE_NOTIFY:
                    printf( " connection was closed gracefully\n" );
                    break;

                case POLARSSL_ERR_NET_CONN_RESET:
                    printf( " connection was reset by peer\n" );
                    break;

                default:
                    printf( " ssl_read returned %d\n", ret );
                    break;
            }

            break;
        }

        len = ret;
        printf( " %d bytes read\n\n%s", len, (char *) buf );
    }
    while( 0 );

    /*
     * 7. Write the 200 Response
     */
    printf( "  > Write to client:" );
    fflush( stdout );

    len = sprintf( (char *) buf, HTTP_RESPONSE,
                   ssl_get_ciphersuite( &ssl ) );

    while( ( ret = ssl_write( &ssl, buf, len ) ) <= 0 )
    {
        if( ret == POLARSSL_ERR_NET_CONN_RESET )
        {
            printf( " failed\n  ! peer closed the connection\n\n" );
            goto accept;
        }

        if( ret != POLARSSL_ERR_NET_WANT_READ && ret != POLARSSL_ERR_NET_WANT_WRITE )
        {
            printf( " failed\n  ! ssl_write returned %d\n\n", ret );
            goto exit;
        }
    }

    len = ret;
    printf( " %d bytes written\n\n%s\n", len, (char *) buf );

    ssl_close_notify( &ssl );
    goto accept;

exit:

    net_close( client_fd );
    x509_free( &srvcert );
    rsa_free( &rsa );
    ssl_free( &ssl );

    cur = s_list_1st;
    while( cur != NULL )
    {
        prv = cur;
        cur = cur->next;
        memset( prv, 0, sizeof( ssl_session ) );
        free( prv );
    }

    memset( &ssl, 0, sizeof( ssl_context ) );

#ifdef WIN32
    printf( "  Press Enter to exit this program.\n" );
    fflush( stdout ); getchar();
#endif

    return( ret );
}
#endif /* POLARSSL_BIGNUM_C && POLARSSL_CERTS_C && POLARSSL_HAVEGE_C &&
          POLARSSL_SSL_TLS_C && POLARSSL_SSL_SRV_C && POLARSSL_NET_C &&
          POLARSSL_RSA_C */

运行结果

client demo 

server demo 

一文详解SSL/TLS协议 SSL/TLS协议是保障网络通信安全的核心技术,其在应用层和传输层之间建立加密通道,文章系统梳理了TLS协议的发展历程、工作原理及最新进展 阅读详情

相关推荐

TLS/SSL Sweet32 attack 、TLS/SSL Weak Cipher Suites漏洞检测及修复

TLS/SSL Sweet32 attack 、TLS/SSL Weak Cipher Suites漏洞

qq274575499的博客 7418

TLS版本及CipherSuites确认及设置

这些报错,有时是因为数据传输双方设置的TLS版本不一致导致,所以如果出现上述报错我们可在确认网络正常的情况下,排除是否是TLS的问题,一般交易伙伴双方确认下彼此使用的TLS版本和Cipher Suites,然后不支持的一方进行设置即可。如果确认是TLS版本和Cipher Suites不支持的问题,我们该如何查看知行之桥支持的TLS版本及TLS Cipher Suites,并进行修改或者设置呢?在这里可以删除不安全的SSL Cipher Suite,添加安全的SSL Cipher Suite,进行应用。

EDI电子数据交换 | 知行软件 1万+

Nginx:SSL/TLS 配置

Nginx是一个高性能的HTTP和反向代理web服务器,是运维中十分常用的中间件,本篇文章将介绍Nginx的SSL/TLS 配置

二次源的博客 1703

SSL知识讲解

ssl

weixin_43743711的博客 1889

传输层安全协议 SSL/TLS 详细介绍

本文对SSL和TLS协议进行一个详细的介绍,以便于大家更直观的理解和认识标准TLS协议。

dvlinker的技术专栏 6156

鸿蒙操作系统资料及列表.zip

这个项目不是官方的。这个项目在互联网上收集一些关于HarmonyOS的文件。 HarmonyOS是第一个基于微内核的全景分布式操作系统。它是华为自主开发的操作系统。HarmonyOS系统于2019年8月9日在华为开发者大会()上正式发布。华为将率先部署智能终端,如智能屏幕,车载终端和可穿戴终端。在未来,越来越多的智能设备将使用开源HarmonyOS。 HarmonyOS实现模块化耦合,这对应于不同设备的灵活部署。HarmonyOS有三层架构。第一层是核心,第二层是基本服务,第三层是程序框架。它可用于大屏幕,PC,汽车和其他不同的设备。它也可以随时用在手机上,但目前华为仍然喜欢Android。 HarmonyOS的底层由未来组成 HarmonyOS micro kernel,Linux kernel并且Lite OS它将成为一个完整的hongmeng微内核架构。 github地址:https://github.com/Awesome-HarmonyOS/HarmonyOS#1-official-resources

SSL/TLS Cipher Suites

Cipher Suite 一个加密算法套件(CipherSuite)是一个四件套,由各类基础的加密算法组成,主要包含了四类: Key Exchange 密钥交换算法; Authentication 身份认证算法; Encryption 对称加密算法; Message Authentication Code 消息认证码算法(信息摘要缩放); 密钥交换算法 顾名思义,该算法用来交换秘钥。 SSL 通信过程(握手结束后)中,双方使用的是对称加密的方式 。由于通信双方以前并不知道彼此的存在,它们也

顺其自然~专栏 4918

远程桌面(RDP)共享USB设备全攻略:不止Hyper-V,你的加密狗和CH340串口也能远程用

本文详细介绍了远程桌面(RDP)共享USB设备的完整解决方案,包括加密狗和CH340串口设备的远程使用技巧。通过RemoteFX USB重定向技术,用户可以在远程会话中无缝使用本地USB设备,提升工作效率。文章涵盖企业级配置、典型设备实战案例及高级故障排除方法,是远程工作者的实用指南。

weixin_42522964的博客 334

openssl - The Cipher Suite 密码套件

在消息传输过程中采用对称加密(比公钥加密在速度上有极大的提高),其所用秘钥(shared secret)在握手过程中中协商(每次对话过程均不同, 在一次对话中都有可能有几次改变),并通过公钥加密的手段由客户端提交服务端. int SSL_set_cipher_list(SSL *s, const char *str); str格式设置为“ECDHE-RSA-AES128-SHA256” int SSL_CTX_set_ciphersuites(SSL_CTX *ctx, const char ..

danielzhou1025的博客 1696

联想Y9000P安装Ubuntu20.04记录

联想Y9000P 2022安装Ubuntu20.04问题记录

Legendyyy的博客 7116

CubeMX配置ADC+DMA避坑实战:如何避免采样过快导致的系统崩溃

本文针对STM32开发中常见的ADC采样过快导致程序卡死问题,提供了基于CubeMX的实战避坑指南。通过分析ADC与DMA协作机制,详解时钟配置、采样时间、DMA缓冲区长度及中断设置等关键步骤,帮助开发者从源头规避系统崩溃风险,实现稳定可靠的数据采集。

weixin_28273593的博客 324

SSL/TLS警告协议详解以及常见握手失败消息的含义与解决方案

警告协议(Alert Protocol)是SSL/TLS协议栈的一部分,它用于在两个通信对等实体之间传输关于连接状态、错误或其他重要条件的通知。当加密会话中发生异常或错误时,一方可以通过发送一个警告消息来通知另一方。

new9232的博客 1万+

【机器学习系列】一文搞懂 零知识机器学习(zkML)

位串行乘法器:实现了Booth编码优化,将乘法分解为移位-加法序列,减少部分积数量50%:模拟脉动阵列的2D网格计算,支持分块(tiling)策略优化内存层次卷积映射:提供直接卷积(行缓冲+滑动窗口)和im2col+GEMM两种硬件映射策略。

VectorShift的博客 156

一文搞懂SSL/TLS

安全套接字层(SSL,Secure Sockets Layer)是基于公钥密码体制和X.509数字证书技术,为网络通信提供数据传输机密性及完整性的一种安全协议,由网景(Netscape)公司于1994年提出。1999年,IETF发布了正式的行业标准[RFC2246],TLS/SSL直正成为通信安全标准。

聚集机器学习、信息安全 1万+

风光储并网对电力系统稳定性影响的仿真研究

本文研究了风光储并网对电力系统稳定性的影响,基于MATLAB/Simulink平台搭建了IEEE 9节点测试系统的风光储并网模型。研究对比了光储、风储和风光储三种并网配置在多种干扰下的稳定性表现。结果表明:光储系统对频率变化最敏感,风储系统具有更强的功率波动适应能力,而风光储联合系统通过互补效应展现出最佳综合稳定性。储能系统在所有配置中均显著改善了频率恢复性能,验证了其在新能源并网中的关键支撑作用。研究为高比例可再生能源电力系统的稳定运行提供了仿真依据和技术参考。

huanghm88的专栏 155

【DaVinci Developer专题】-8-创建一个枚举Enum ADT(Application Data Type)

目录 1 创建一个枚举Value ADT(Application Data Type) 1.1 命名application data type 1.2 创建一个computation method计算方法属性 1.3 创建一个Contraint约束条件属性 2 创建了一个新的Type Mapping Sets 3 创建了一个S/R Port Interface 4 SWC引用Type Mapping set 5 导入CFG生成代码的总结 6 结尾 <--返回「实战篇」博文-总目录-

「汽车电子助手」的博客 2292

TLS/SSL 工作原理及握手过程详解

目录 前言 TLS/SSL 基础概念 密钥协商过程中存在的问题及解决办法 TLS/SSL 握手过程 前言 本文是对HTTPS 安全基础、TLS/SSL 工作原理及握手过程的总结。第一部分介绍为 HTTPS 提供安全基础的 TLS/SSL 的基础概念,及数据传输过程中密钥协商的原因。第二部分介绍密钥协商过程中存在的问题,及解决办法,其中会涉及PKI、CA 等概念。最后介绍 TLS/SSL 的握手过程。 HTTP 和 HTTPS 的区别:https://blog.youkuaiyun.com/qq_382..

Tyler_Zx的博客 2万+

025、Zephyr RTOS设备树覆盖与修改

本文分享了在Zephyr RTOS中使用设备树覆盖(overlay)的实战经验。作者通过一个工业数据采集项目中GPIO无法拉高的调试案例,揭示了设备树覆盖的"叠加"本质而非简单替换。文章详细介绍了覆盖文件的正确编写方式,包括节点引用、pinctrl配置等技巧,并总结了常见陷阱如状态设置不完整、别名冲突等问题。特别强调了条件覆盖的用法和调试方法,最后提出了覆盖文件管理的五项实用原则,强调设备树覆盖是硬件与软件之间的重要契约,需要谨慎对待。全文以实际项目为背景,提供了可操作性强的技术建议。

m0_50546716的博客 33

SSL/TLS,SSL,TLS分别是什么

因为虽然 SSL 存在一些历史遗留的安全问题且已逐渐被 TLS 替代,但它们的核心功能都是致力于实现网络通信的安全加密、数据完整性保护以及身份验证等,从功能和应用目的角度有很大的共性,所以用 “SSL/TLS” 来概括表述,方便人们在讨论相关安全协议时进行指代,而不用特意区分具体是 SSL 还是 TLS 协议,除非是在特定的历史背景介绍或者深入对比二者差异的情境下。:沿用了类似 SSL 的消息摘要生成 MAC 来验证数据完整性的思路,但使用了更安全可靠的哈希算法等,进一步降低数据被篡改而不被发现的风险。

qq_62097431的博客 1693

姿态传感器/陀螺仪之ICM-42670-P应用原理图设计

ICM-42670-P采用LGA-14封装,尺寸为2.5x3x0.76毫米,工作电压范围为1.71V至3.6V,支持I3CSM、I2C和SPI串行通信接口。其设计目标是提供高精度、低功耗和小型化的解决方案,以满足消费类和工业应用的需求。ICM-42670-P是一款由TDK InvenSense推出的高性能六轴MEMS运动追踪传感器,集成了3轴陀螺仪和3轴加速度计,适用于多种应用场景,包括可穿戴设备、游戏控制器、无人机、AR/VR设备等。

corlin6688的博客 1206

深度学习工具包 DeepLearningToolbox

深度学习工具包Deprecation notice.-----This toolbox is outdated and no longer maintained.There are much better tools available for deep learning than this toolbox, e.g. [Theano](http://deeplearning.net/software/theano/), [torch](http://torch.ch/) or [tensorflow](http://www.tensorflow.org/)I would suggest you use one of the tools mentioned above rather than use this toolbox.Best, Rasmus.DeepLearnToolbox================A Matlab toolbox for Deep Learning.Deep Learning is a new subfield of machine learning that focuses on learning deep hierarchical models of data.It is inspired by the human brain's apparent deep (layered, hierarchical) architecture.A good overview of the theory of Deep Learning theory is[Learning Deep Architectures for AI](http://www.iro.umontreal.ca/~bengioy/papers/ftml_book.pdf)For a more informal introduction, see the following videos by Geoffrey Hinton and Andrew Ng.* [The Next Generation of Neural Networks](http://www.youtube.com/watch?v=AyzOUbkUf3M) (Hinton, 2007)* [Recent Developments in Deep Learning](http://www.youtube.com/watch?v=VdIURAu1-aU) (Hinton, 2010)* [Unsupervised Feature Learning and Deep Learning](http://www.youtube.com/watch?v=ZmNOAtZIgIk) (Ng, 2011)If you use this toolbox in your research please cite [Prediction as a candidate for learning deep hierarchical models of data](http://www2.imm.dtu.dk/pubdb/views/publication_details.php?id=6284)```@MASTERSTHESIS\{IMM2012-06284, author = "R. B. Palm", title = "Prediction as a candidate for learning deep hierarchical models of data", year = "2012",}```Contact: rasmusbergpalm at gmail dot comDirectories included in the toolbox-----------------------------------`NN/` - A library for Feedforward Backpropagation Neural Networks`CNN/` - A library for Convolutional Neural Networks`DBN/` - A library for Deep Belief Networks`SAE/` - A library for Stacked Auto-Encoders`CAE/` - A library for Convolutional Auto-Encoders`util/` - Utility functions used by the libraries`data/` - Data used by the examples`tests/` - unit tests to verify toolbox is workingFor references on each library check REFS.mdSetup-----1. Download.2. addpath(genpath('DeepLearnToolbox'));Example: Deep Belief Network---------------------```matlabfunction test_example_DBNload mnist_uint8;train_x = double(train_x) / 255;test_x = double(test_x) / 255;train_y = double(train_y);test_y = double(test_y);%% ex1 train a 100 hidden unit RBM and visualize its weightsrand('state',0)dbn.sizes = [100];opts.numepochs = 1;opts.batchsize = 100;opts.momentum = 0;opts.alpha = 1;dbn = dbnsetup(dbn, train_x, opts);dbn = dbntrain(dbn, train_x, opts);figure; visualize(dbn.rbm{1}.W'); % Visualize the RBM weights%% ex2 train a 100-100 hidden unit DBN and use its weights to initialize a NNrand('state',0)%train dbndbn.sizes = [100 100];opts.numepochs = 1;opts.batchsize = 100;opts.momentum = 0;opts.alpha = 1;dbn = dbnsetup(dbn, train_x, opts);dbn = dbntrain(dbn, train_x, opts);%unfold dbn to nnnn = dbnunfoldtonn(dbn, 10);nn.activation_function = 'sigm';%train nnopts.numepochs = 1;opts.batchsize = 100;nn = nntrain(nn, train_x, train_y, opts);[er, bad] = nntest(nn, test_x, test_y);assert(er < 0.10, 'Too big error');```Example: Stacked Auto-Encoders---------------------```matlabfunction test_example_SAEload mnist_uint8;train_x = double(train_x)/255;test_x = double(test_x)/255;train_y = double(train_y);test_y = double(test_y);%% ex1 train a 100 hidden unit SDAE and use it to initialize a FFNN% Setup and train a stacked denoising autoencoder (SDAE)rand('state',0)sae = saesetup([784 100]);sae.ae{1}.activation_function = 'sigm';sae.ae{1}.learningRate = 1;sae.ae{1}.inputZeroMaskedFraction = 0.5;opts.numepochs = 1;opts.batchsize = 100;sae = saetrain(sae, train_x, opts);visualize(sae.ae{1}.W{1}(:,2:end)')% Use the SDAE to initialize a FFNNnn = nnsetup([784 100 10]);nn.activation_function = 'sigm';nn.learningRate = 1;nn.W{1} = sae.ae{1}.W{1};% Train the FFNNopts.numepochs = 1;opts.batchsize = 100;nn = nntrain(nn, train_x, train_y, opts);[er, bad] = nntest(nn, test_x, test_y);assert(er < 0.16, 'Too big error');```Example: Convolutional Neural Nets---------------------```matlabfunction test_example_CNNload mnist_uint8;train_x = double(reshape(train_x',28,28,60000))/255;test_x = double(reshape(test_x',28,28,10000))/255;train_y = double(train_y');test_y = double(test_y');%% ex1 Train a 6c-2s-12c-2s Convolutional neural network %will run 1 epoch in about 200 second and get around 11% error. %With 100 epochs you'll get around 1.2% errorrand('state',0)cnn.layers = { struct('type', 'i') %input layer struct('type', 'c', 'outputmaps', 6, 'kernelsize', 5) %convolution layer struct('type', 's', 'scale', 2) %sub sampling layer struct('type', 'c', 'outputmaps', 12, 'kernelsize', 5) %convolution layer struct('type', 's', 'scale', 2) %subsampling layer};cnn = cnnsetup(cnn, train_x, train_y);opts.alpha = 1;opts.batchsize = 50;opts.numepochs = 1;cnn = cnntrain(cnn, train_x, train_y, opts);[er, bad] = cnntest(cnn, test_x, test_y);%plot mean squared errorfigure; plot(cnn.rL);assert(er<0.12, 'Too big error');```Example: Neural Networks---------------------```matlabfunction test_example_NNload mnist_uint8;train_x = double(train_x) / 255;test_x = double(test_x) / 255;train_y = double(train_y);test_y = double(test_y);% normalize[train_x, mu, sigma] = zscore(train_x);test_x = normalize(test_x, mu, sigma);%% ex1 vanilla neural netrand('state',0)nn = nnsetup([784 100 10]);opts.numepochs = 1; % Number of full sweeps through dataopts.batchsize = 100; % Take a mean gradient step over this many samples[nn, L] = nntrain(nn, train_x, train_y, opts);[er, bad] = nntest(nn, test_x, test_y);assert(er < 0.08, 'Too big error');%% ex2 neural net with L2 weight decayrand('state',0)nn = nnsetup([784 100 10]);nn.weightPenaltyL2 = 1e-4; % L2 weight decayopts.numepochs = 1; % Number of full sweeps through dataopts.batchsize = 100; % Take a mean gradient step over this many samplesnn = nntrain(nn, train_x, train_y, opts);[er, bad] = nntest(nn, test_x, test_y);assert(er < 0.1, 'Too big error');%% ex3 neural net with dropoutrand('state',0)nn = nnsetup([784 100 10]);nn.dropoutFraction = 0.5; % Dropout fraction opts.numepochs = 1; % Number of full sweeps through dataopts.batchsize = 100; % Take a mean gradient step over this many samplesnn = nntrain(nn, train_x, train_y, opts);[er, bad] = nntest(nn, test_x, test_y);assert(er < 0.1, 'Too big error');%% ex4 neural net with sigmoid activation functionrand('state',0)nn = nnsetup([784 100 10]);nn.activation_function = 'sigm'; % Sigmoid activation functionnn.learningRate = 1; % Sigm require a lower learning rateopts.numepochs = 1; % Number of full sweeps through dataopts.batchsize = 100; % Take a mean gradient step over this many samplesnn = nntrain(nn, train_x, train_y, opts);[er, bad] = nntest(nn, test_x, test_y);assert(er < 0.1, 'Too big error');%% ex5 plotting functionalityrand('state',0)nn = nnsetup([784 20 10]);opts.numepochs = 5; % Number of full sweeps through datann.output = 'softmax'; % use softmax outputopts.batchsize = 1000; % Take a mean gradient step over this many samplesopts.plot = 1; % enable plottingnn = nntrain(nn, train_x, train_y, opts);[er, bad] = nntest(nn, test_x, test_y);assert(er < 0.1, 'Too big error');%% ex6 neural net with sigmoid activation and plotting of validation and training error% split training data into training and validation datavx = train_x(1:10000,:);tx = train_x(10001:end,:);vy = train_y(1:10000,:);ty = train_y(10001:end,:);rand('state',0)nn = nnsetup([784 20 10]); nn.output = 'softmax'; % use softmax outputopts.numepochs = 5; % Number of full sweeps through dataopts.batchsize = 1000; % Take a mean gradient step over this many samplesopts.plot = 1; % enable plottingnn = nntrain(nn, tx, ty, opts, vx, vy); % nntrain takes validation set as last two arguments (optionally)[er, bad] = nntest(nn, test_x, test_y);assert(er < 0.1, 'Too big error');```[![Bitdeli Badge](https://d2weczhvl823v0.cloudfront.net/rasmusbergpalm/deeplearntoolbox/trend.png)](https://bitdeli.com/free "Bitdeli Badge")

SSL/TLS

文章目录(一)介绍(二)客户端和服务端(三)SSL和TLS区别(四)使用SSL/TLS进行通信(五)TLS小结(六)对SSL/TLS的攻击 (一)介绍 SSL/TLS是世界上应用最广泛的密码通信方法。比如说,当在网上商城中输人信用卡号时,我们的Web浏览器就会使用SSL/TLS进行密码通信。使用SSL/TLS可以对通信对象进行认证,还可以确保通信内容的机密性。 SSL/TLS中综合运用了对称密码、消息认证码、公钥密码、数字签名、伪随机数生成器等密码技术。严格来说,SSL ( Secure Socket La

发现问题,面对问题,分析问题,解决问题,总结问题 2826

Devexpress16.2.6破解工具

Devexpress16.2.6破解工具Devexpress16.2.6破解工具Devexpress16.2.6破解工具Devexpress16.2.6破解工具

SSL/TLS加密

SSL/TLS是确保网络通信安全的关键技术,尤其是在处理敏感信息(如登录凭证、支付信息等)时,使用HTTPS是必不可少的。作为前端开发者,虽然不需要直接配置SSL/TLS,但了解其工作原理有助于更好地理解网络安全。在用户点击页面的数据请求接口时,如果请求的是同一台服务器的资源,通常不需要重新进行完整的SSL/TLS握手。浏览器会通过连接复用和TLS会话恢复机制,快速建立或恢复加密连接,从而提高性能。四、会话恢复机制是如何快速恢复的。

weixin_44356698的博客 1926

数学建模模型总结

这是本人在两年内准备参加数学建模竞赛搜集到的模型资料,已经经过了本人的筛选和整理,希望能够对准备参加数学建模竞赛的学弟学妹们提供一些帮助!

计算机控制技术及应用

《计算机控制技术及应用》通过总结作者的科研成果和吸收国内外的先进理论、方法和技术,以计算机控制系统的网络化、开放化、智能化和集成化发展趋势为主线索,主要介绍计算机控制系统的基本概念和计算机控制系统的典型形式,计算机控制系统的数学描述与基本分析方法,以及数字PID控制器、最少拍控制系统、达林算法、状态变量设计法等设计方法及其各种改进算法。重点突出计算机控制系统输入输出通道接口的设计方法和典型控制系统的设计案例与实现方法等。

一篇文章让你彻底弄懂SSL/TLS协议

文章目录SSL/TLS的应用TLS协议的架构握手协议主密码和预备主密码TLS记录协议 一篇文章让你彻底弄懂SSL/TLS协议 SSL/TLS是一种密码通信框架,他是世界上使用最广泛的密码通信方法。SSL/TLS综合运用了密码学中的对称密码,消息认证码,公钥密码,数字签名,伪随机数生成器等,可以说是密码学中的集大成者。 SSL(Secure Socket Layer)安全套接层,是1994年由Net...

程序那些事 1万+

SSL/TLS握手

这种方法可确保更高效、更安全地协商加密密钥。TLS:Transport Layer Security (传输层安全协议),是SSL的升级版本,用于修复SSL安全漏洞,虽然TLS被广泛使用,但依然沿用SSL称呼。TLS1.3(2018) 大幅简化了握手过程,减少了延迟,引入了前向保密性(Forward Secrecy)作为默认特性,是目前的最新版本,广泛推行和应用。TLS1.2(2008) 引入了更多加密算法支持,改进了密钥导出和签名计算方式,更加灵活安全,目前依然广泛使用,被认为是安全的。

Dean_xiu的博客 1471

高频八股——SSL/TLS的握手过程

在计算机网络的八股问题中,面试官最常问的一个问题就是:“SSL/TLS的握手过程是怎样的”,网络上的文章五花八门,概括的“握手过程”也各不相同,于是便写篇文章帮助自己理解和回顾,也希望这篇文章可以带你深入理解计算机网络中的SSL/TLS是什么,以及它的握手过程是如何进行的。

weixin_49426115的博客 1510

SSL/TLS协议简介

SSL(Secure Sockets Layer) 是一种网络安全协议,用于在互联网中保护数据的传输。SSL 协议最初由网景公司(Netscape)开发,旨在为通过互联网传输的数据提供加密保护。由于 SSL 协议存在一些安全问题,它在 1999 年被其继任者 TLS(Transport Layer Security) 取代。尽管 TLS 是 SSL 的继任者,但 SSL 和 TLS 常常被统称为 SSL/TLS,尤其在日常用语中。

mickey2007的博客 4064
上一篇: 在内核协议栈植入一段代码
下一篇: 安全算法的一些总结
security_yj
博客等级 码龄5年 13粉丝 15原创
评论
成就一亿技术人!
拼手气红包6.0元
还能输入1000个字符
 
 条评论被折叠 查看
添加红包

请填写红包祝福语或标题

个

红包个数最小为10个

元

红包金额最低5元

当前余额3.43元 前往充值 >
需支付:10.00元
成就一亿技术人!
领取后你会自动成为博主和红包主的粉丝 规则
hope_wisdom
发出的红包
实付元
使用余额支付
点击重新获取
扫码支付
钱包余额 0

抵扣说明:

1.余额是钱包充值的虚拟货币,按照1:1的比例进行支付金额的抵扣。
2.余额无法直接购买下载,可以购买VIP、付费专栏及课程。

余额充值