我正在尝试编写一个内核模块，该模块会将所有HTTP数据包数据转储到dmesg。 我在POST ROUTING中注册了一个nf_hook（也尝试了挂钩OUTPUT表），并打印所有运动为80的数据包（HTTP响应）

我阅读了以下帖子-Print TCP Packet Data

真的很有效！但我有一个问题，内核模块仅打印响应的第一行-HTTP/1.0 200 OK，而不打印所有HTTP标头和HTML。

这是我的钩子函数-

    struct iphdr *iph;          /* IPv4 header */
    struct tcphdr *tcph;        /* TCP header */
    u16 sport,dport;           /* Source and destination ports */
    u32 saddr,daddr;           /* Source and destination addresses */
    unsigned char *user_data;   /* TCP data begin pointer */
    unsigned char *tail;        /* TCP data end pointer */
    unsigned char *it;          /* TCP data iterator */

    /* Network packet is empty,seems like some problem occurred. Skip it */
    if (!skb)
        return NF_accEPT;

    iph = ip_hdr(skb);          /* get IP header */

    /* Skip if it's not TCP packet */
    if (iph->protocol != IPPROTO_TCP)
        return NF_accEPT;

    tcph = tcp_hdr(skb);        /* get TCP header */

    /* Convert network endianness to host endiannes */
    saddr = ntohl(iph->saddr);
    daddr = ntohl(iph->daddr);
    sport = ntohs(tcph->source);
    dport = ntohs(tcph->dest);

    /* Watch only port of interest */
    if (sport != PTCP_WATCH_PORT)
        return NF_accEPT;

    /* Calculate pointers for begin and end of TCP packet data */
    user_data = (unsigned char *)((unsigned char *)tcph + (tcph->doff * 4));
    tail = skb_tail_pointer(skb);

    /* ----- Print all needed information from received TCP packet ------ */

    /* Show only HTTP packets */
    if (user_data[0] != 'H' || user_data[1] != 'T' || user_data[2] != 'T' ||
            user_data[3] != 'P') {
        return NF_accEPT;
    }

    /* Print packet route */
    pr_debug("print_tcp: %pI4h:%d -> %pI4h:%d\n",&saddr,sport,&daddr,dport);

    /* Print TCP packet data (payload) */
    pr_debug("print_tcp: data:\n");
    for (it = user_data; it != tail; ++it) {
        char c = *(char *)it;

        if (c == '\0')
            break;

        printk("%c",c);
    }
    printk("\n\n");

    return NF_accEPT;

我想打印整个数据包，而不仅仅是第一行。 为什么只打印第一行？我的猜测是有一些路由缓存（例如使用IPTABLES时），有没有办法禁用缓存？