#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sasl/sasl.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <linux/in.h>

#define SAMPLE_SEC_BUF_SIZE (2048)

char buf[SAMPLE_SEC_BUF_SIZE];

static sasl_conn_t *conn = NULL;
const char *realm = "TEST.COM";
const char *mech = "GSSAPI";
const char *iplocal = "127.0.0.1";
const char *ipremote = "127.0.0.1";
char *searchpath = NULL;
const char *service = "server";
const char *fqdn = "hadoop.test.com";
int cfd;

int init_sasl() {
    int result = sasl_client_init(NULL);
    if (result != SASL_OK) {
        printf("Initializing libsasl\n");
        return -1;
    }
    printf("sasl_client_init ok\n");
    return 0;
}

int connect_server() {
    struct sockaddr_in s_add, c_add;
    unsigned short portnum = 2345;
    printf("Hello,welcome to client !\n");
    cfd = socket(AF_INET, SOCK_STREAM, 0);
    if (-1 == cfd) {
        printf("socket fail ! \n");
        return 1;
    }
    printf("socket ok !\n");
    bzero(&s_add, sizeof(struct sockaddr_in));
    s_add.sin_family = AF_INET;
    s_add.sin_addr.s_addr = inet_addr("127.0.0.1");
    s_add.sin_port = htons(portnum);

    if (-1 == connect(cfd, (struct sockaddr *)(&s_add), sizeof(struct sockaddr))) {
        printf("connect fail !\n");
        return 1;
    }
    printf("connect ok !\n");
    return 0;
}

int readTicket(char *ticket) {
    char len_str[10] = {0};
    int recbytes;
    if (-1 == (recbytes = read(cfd, len_str, 10))) {
        printf("read len fail !\n");
        close(cfd);
        return 0;
    }
    char buffer[1024] = {0};
    int len = atoi(len_str);
    printf("read len=%s\n", len_str);
    if (-1 == (recbytes = read(cfd, ticket, len))) {
        printf("read data fail !\n");
        close(cfd);
        return 0;
    }
	return len;

}

void writeTicket(char *data, unsigned len) {
    char len_str[10] = {0};
    sprintf(len_str, "%d", len);
    if (-1 == write(cfd, len_str, 10)) {
        printf("write failed\n");
        return 1;
    }
    if (-1 == write(cfd, data, len)) {
        printf("write failed\n");
        return 1;
    }
}

int auth_sever() {
    printf("begin auth\n");
    int result = sasl_client_new("server", fqdn, NULL, NULL, NULL, 0, &conn);
    if (result != SASL_OK) {
        printf("client new client failed\n");
        return 1;
    }
    char data[1024] = {0};
    unsigned len = 0;
    printf("begin sasl_client_start\n");
    result = sasl_client_start(conn, mech, NULL, &data, &len, &mech);
    if (result != SASL_OK && result != SASL_CONTINUE) {
        printf("client auth start failed error:%s\n", sasl_errdetail(conn));
        return 1;
    }
    //data[len] = '\0';
    printf("sasl_client_start ok: ticket=%s, len=%d\n", data, len);
    while (1) {
        char len_str[10] = {0};
        writeTicket(data, len);
		char *buffer;
        int size = readTicket(buffer);

        result = sasl_client_step(conn, buffer, size, NULL, &data, &len);
        if (result != SASL_OK && result != SASL_CONTINUE) {
            printf("auth failed, %s\n", sasl_errdetail(conn));
            return 1;
        }
    }
    return 0;
}

int main() {
    int result;
    const char *data;
    const char *chosenmech;
    int serverlast = 0;
    unsigned len;
    char *userid = NULL;
    char *authid = NULL;

    int recbytes;
    int sin_size;
    char buffer[1024] = {0};

    if (connect_server() != 0) {
        return 1;
    }

    if (init_sasl() != 0) {
        return 1;
    }

    if (-1 == (recbytes = read(cfd, buffer, 1024))) {
        printf("read data fail !\n");
        return -1;
    }

    if (strcmp(buffer, "need_auth") == 0 && auth_sever() != 0) {
        printf("auth failed\n");
        return -1;
    }
    printf("auth ok\nREC:\n");

    buffer[recbytes] = '\0';
    printf("%s\n", buffer);

    auth_sever();

    getchar();
    close(cfd);

    if (init_sasl() != 0) {
        return 1;
    }
    return 0;
}