我正在尝试编写一个可以在Wireshark中使用的.pcap文件。为此,我有一些包含各种数据类型的结构体需要写入文件(见代码)。
所以,我创建了结构体实例,填充了数据,使用FILE *fp = fopen("test.pcap","w"),然后我不确定如何正确地将其写入文件。我相信我应该使用memcpy,但我不确定最佳方法是什么。过去,我大多数情况下都依赖于C++库来完成这项工作。有什么建议吗?
typedef struct pcap_hdr_s {
uint32_t magic_number; /* magic number */
uint16_t version_major; /* major version number */
uint16_t version_minor; /* minor version number */
int32_t thiszone; /* GMT to local correction */
uint32_t sigfigs; /* accuracy of timestamps */
uint32_t snaplen; /* max length of captured packets, in octets */
uint32_t network; /* data link type */
} pcap_hdr_t;
typedef struct pcaprec_hdr_s {
uint32_t ts_sec; /* timestamp seconds */
uint32_t ts_usec; /* timestamp microseconds */
uint32_t incl_len; /* number of octets of packet saved in file */
uint32_t orig_len; /* actual length of packet */
} pcaprec_hdr_t;
typedef struct ethernet_hdr_s {
uint8_t dst[6]; /* destination host address */
uint8_t src[6]; /* source host address */
uint16_t type; /* IP? ARP? RARP? etc */
} ethernet_hdr_t;
typedef struct ip_hdr_s {
uint8_t ip_hl:4, /* both fields are 4 bits */
ip_v:4;
uint8_t ip_tos;
uint16_t ip_len;
uint16_t ip_id;
uint16_t ip_off;
uint8_t ip_ttl;
uint8_t ip_p;
uint16_t ip_sum;
uint32_t ip_src;
uint32_t ip_dst;
}ip_hdr_t;
typedef struct udp_header
{
uint16_t src;
uint16_t dst;
uint16_t length;
uint16_t checksum;
} udp_header_t;