原始套接字不发送

我想写一个示例原始套接字程序来清除我的原始套接字的理解。 我创build一个Raw UDP套接字，然后调用sendto。 我sendto成功，但我从来没有看到对方收到的数据包。 我没有任何接收方运行，所以我依靠在发送方和接收方上运行的Wireshark。 我正在粘贴这里的代码片段。 请指出任何错误。

#include<stdio.h> #include<stdlib.h> #include<sys/types.h> #include<netinet/in.h> #include<string.h> #include "protHeaders.x" #include "gen.h" U16 csum(U16* buf, S32 nwords) { U32 sum; for (sum = 0; nwords > 0; nwords--) sum += *buf++; sum = (sum >> 16) + (sum & 0xffff); sum += (sum >> 16); return ~sum; }/*csum*/ int main(int argc,char** argv) { U8 datagram[MAX_IPPACKET]; U8 udpPayLoad[MAX_UDPPAYLOAD]; CustIpHeader* ipH; CustUdpHeader* udpH; struct sockaddr_in sin; S32 sockFd; S32 one = 1; const S32* val = &one; ipH = (CustIpHeader *)datagram; udpH = (CustUdpHeader *)(datagram + sizeof(CustIpHeader)); memset(datagram,0,sizeof(datagram)); memset(udpPayLoad,0,sizeof(udpPayLoad)); memset(&sin,0,sizeof(struct sockaddr_in)); strcpy(udpPayLoad,"<<<<Aditya>>>>"); sin.sin_family = AF_INET; sin.sin_port = htons(atoi(argv[4])); /* fill the Ip header */ ipH->ip_hl = 5; ipH->ip_v = 4; ipH->ip_tos = 0; ipH->ip_len = sizeof(CustIpHeader) + sizeof(CustUdpHeader) + strlen(udpPayLoad); ipH->ip_id = htonl(54321); ipH->ip_off = 0; ipH->ip_p = 17; ipH->ip_ttl = 65; ipH->ip_sum = 0; ipH->ip_src.s_addr = inet_addr(argv[1]); ipH->ip_dst.s_addr = inet_addr(argv[3]); /* fill the Udp header */ udpH->uh_sport = htons(atoi(argv[2])); udpH->uh_dport = htons(atoi(argv[4])); udpH->uh_len = sizeof(CustUdpHeader) + strlen(udpPayLoad); udpH->uh_check = 0; printf("Checksum = %u\n",udpH->uh_check); /* copy udpPayLoad */ strcpy(datagram+sizeof(CustIpHeader)+sizeof(CustUdpHeader),udpPayLoad); #if 1 printf("Datagram %p,UdpPayload %p\n",(void *)datagram,(void *)datagram+sizeof(CustIpHeader)+sizeof(CustUdpHeader)); printf("IpHeader %p, UdpHeader %p\n",(void *)ipH,udpH); #endif /* fill in the checksum */ ipH->ip_sum = csum((U16 *)datagram,ipH->ip_len >> 1); printf("Checksum = %u\n",ipH->ip_sum); if ((sockFd = socket(PF_INET,SOCK_RAW,IPPROTO_UDP)) < 0) { perror("socket:create"); RETURN(RFAILED); } /* doing the IP_HDRINCL call */ if (setsockopt(sockFd,IPPROTO_IP,IP_HDRINCL,val,sizeof(one)) < 0) { perror("Client:setsockopt"); } while(1) { if ( sendto(sockFd, datagram, ipH->ip_len, 0, (struct sockaddr *)&sin, sizeof (sin)) < 0) { perror("Client:sendto"); } else printf("."); } RETURN(ROK); } 

IP和UDP标头是：

 typedef struct _ipheader { U8 ip_hl:4,ip_v:4; /* ip_hl: the ip header length in 32bit octets. * ip_v : ip version (always 4 for our case). */ U8 ip_tos; /* reliability of the service. 0x00 is Normal */ U16 ip_len; /* totoal length including ip header,icmp/tcp/udp header * and payload size in bytes */ U16 ip_id; /* sequence no. used for reassembly of fragmented IP packets */ U16 ip_off; /* the fragment offset used for reassembly of fragmented packets */ U16 ip_p; /* the transport layer protocol. can be tcp (6), udp(17) */ U8 ip_ttl; /* time to live */ U16 ip_sum; /* the datagram checksum for the whole IP packet */ struct in_addr ip_src; /* the source IP address, converted to a long format */ struct in_addr ip_dst; /* the desitnation IP address, converted to a long format */ }CustIpHeader; /* total ip header length: 20 bytes */ typedef struct _udpheader { U16 uh_sport; /* The source port that a client bind()s to */ U16 uh_dport; /* The desination port that a server bind()s to*/ U16 uh_len; /* The length of udp header and payload data in bytes */ U16 uh_check; /* The checksum of header and data */ }CustUdpHeader; /* total udp header length: 8 bytes (=64 bits) */ 

我以root用户身份运行，所以权限不是问题。

语言：C

• 使用NASM和TCP套接字
• 如何确定是否完成从UNIX套接字读取（）？
• cURL请求从Unix的套接字
• 在新terminal执行subprocess
• perl，使用IO :: Select和IO :: Socket :: INET读取阻塞

操作系统：Linux