openssl 握手失败

我正在尝试编写简单的 C openssl 客户端和服务器。这是客户的代码：

int main() {
    int err;

    SSL_CTX * ctx = init_ctx("client-cert.pem", "client-private.pem", "certs/cacert.pem", "clientpass");
    if (!ctx) {
        fprintf(stderr, "couldn't init ctx\n");
        exit(1);
    }

    int sock = tcp_connect("localhost", 4443);

    /* Connect the SSL socket */
    SSL * ssl = SSL_new(ctx);
    BIO * sbio = BIO_new_socket(sock,BIO_NOCLOSE);
    SSL_set_bio(ssl,sbio,sbio);

    if((err = SSL_connect(ssl)) != 1) {
        switch(SSL_get_error(ssl, err)) {
            case SSL_ERROR_NONE:
            fprintf(stderr, "error SSL_ERROR_NONE\n");
            break;
            case SSL_ERROR_ZERO_RETURN:
            fprintf(stderr, "errorSSL_ERROR_ZERO_RETURN \n");
            break;
            case SSL_ERROR_WANT_READ:
            fprintf(stderr, "error SSL_ERROR_WANT_READ\n");
            break;
            case SSL_ERROR_WANT_WRITE:
            fprintf(stderr, "error SSL_ERROR_WANT_WRITE\n");
            break;
            case SSL_ERROR_WANT_CONNECT:
            fprintf(stderr, "error SSL_ERROR_WANT_CONNECT\n");
            break;
            case SSL_ERROR_WANT_X509_LOOKUP:
            fprintf(stderr, "error SSL_ERROR_WANT_X509_LOOKUP\n");
            break;
            case SSL_ERROR_SYSCALL:
            fprintf(stderr, "error SSL_ERROR_SYSCALL\n");
            break;
            case SSL_ERROR_SSL:
            fprintf(stderr, "error SSL_ERROR_SSL\n");
            break;
            default:
            fprintf(stderr, "error f****** s***!!!\n");
            break;
        }
        fprintf(stderr, "%s\n", ERR_error_string(ERR_get_error(), NULL));
        ERR_print_errors_fp(stderr);
        //exit(1);
    }

    check_cert(ssl, "host.com");
    fprintf(stderr, "%d bytes sent\n", send_request(ssl, "come with me, we'll go dreaming"));   

    /* shutdown ssl connection */
    err = SSL_shutdown(ssl);
    if (err < 0) {
        ERR_print_errors_fp(stderr);
        exit(1);
    }

    close(sock);
    SSL_free(ssl);
    SSL_CTX_free(ctx);

    return 0;
}

ssize_t send_request(SSL * ssl, const char * req) {
    fprintf(stderr, "sending request...\n");
    ssize_t size = SSL_write(ssl, req, strlen(req));

    if (size < 0) {
        ERR_print_errors_fp(stderr);
    }

    return size;
}

SSL_get_error(ssl, err)回报SSL_ERROR_SYSCALL and send_request返回以下错误：5269:error:140790E5:SSL routines:SSL23_WRITE:ssl handshake failure:s23_lib.c:188:。我正在设置用密码保护的私钥pem_password_cb打回来：

SSL_CTX_set_default_passwd_cb(ctx, passwd_func);
SSL_CTX_set_default_passwd_cb_userdata(ctx, (void *)password);

。使用 v23 方法...我不知道这次握手失败的原因...

我尝试过这样的调试：openssl s_client -connect localhost:4443 -cert sberbank-cert.pem -key sberbank-private.pem -verify 1 -CAfile cacert.pem -prexit -msg我有以下结果：

milo@milonote:~/src/tests/ssl$ openssl s_client -connect localhost:4443 -cert sberbank-cert.pem -key sberbank-private.pem -verify 1 -CAfile cacert.pem -prexit  -msg
verify depth is 1
CONNECTED(00000003)
>>> TLS 1.0 Handshake [length 005a], ClientHello
    01 00 00 56 03 01 4d ed fc 5e a7 d7 56 6a 70 40
    0c a6 19 d0 06 23 08 28 65 07 53 46 d1 87 c0 c2
    a2 27 d8 5b ad ac 00 00 28 00 39 00 38 00 35 00
    16 00 13 00 0a 00 33 00 32 00 2f 00 05 00 04 00
    15 00 12 00 09 00 14 00 11 00 08 00 06 00 03 00
    ff 02 01 00 00 04 00 23 00 00
5825:error:140790E5:SSL routines:SSL23_WRITE:ssl handshake failure:s23_lib.c:188:
---
no peer certificate available
---
No client certificate CA names sent
---
SSL handshake has read 0 bytes and written 95 bytes
---
New, (NONE), Cipher is (NONE)
Secure Renegotiation IS NOT supported
Compression: NONE
Expansion: NONE
---

这是来源tcp_connect。我确信它不会失败，因为它返回 fd （不是-1):

int tcp_connect(const char *host, int port) {
    struct hostent *hp;
    struct sockaddr_in addr;
    int sock;

    if(!(hp=gethostbyname(host)))
        return -1;

    memset(&addr,0,sizeof(addr));
    addr.sin_addr=*(struct in_addr*)
    hp->h_addr_list[0];
    addr.sin_family=AF_INET;
    addr.sin_port=htons(port);

    if((sock=socket(AF_INET,SOCK_STREAM, IPPROTO_TCP))<0)
       return -1;

    if(connect(sock,(struct sockaddr *)&addr, sizeof(addr))<0)
        return -1;

    return sock;
}

我已经解决了我的问题！不是客户端，而是服务器端！服务器在收到 SSL_WANT_READ 错误时关闭 tcp 连接，而不是重复 SSL_accept。感谢您的参与！