xt_ipp2p: move result printing code into separate functions

Signed-off-by: Jeremy Sowden <jeremy@azazel.net>

diff --git a/extensions/xt_ipp2p.c b/extensions/xt_ipp2p.c
index 0ed4412aaeec9c61c4b85fee89869faa8345af88..3c0fb2d733050d65e7c225f901ac080633d22d4d 100644 (file)
--- a/extensions/xt_ipp2p.c
+++ b/extensions/xt_ipp2p.c
@@ -19,6 +19,25 @@ MODULE_AUTHOR("Eicke Friedrich/Klaus Degner <ipp2p@ipp2p.org>");
 MODULE_DESCRIPTION("An extension to iptables to identify P2P traffic.");
 MODULE_LICENSE("GPL");
 
+union ipp2p_addr {
+       __be32 ip;
+};
+
+struct ipp2p_result_printer {
+       const union ipp2p_addr *saddr, *daddr;
+       short sport, dport;
+       void (*print)(const union ipp2p_addr *, short, const union ipp2p_addr *, short, bool, unsigned int);
+};
+
+static void
+print_result(const struct ipp2p_result_printer *rp, bool result,
+             unsigned int hlen)
+{
+       rp->print(rp->saddr, rp->sport,
+                 rp->daddr, rp->dport,
+                 result, hlen);
+}
+
 /* Search for UDP eDonkey/eMule/Kad commands */
 static unsigned int
 udp_search_edk(const unsigned char *t, const unsigned int packet_len)
@@ -807,10 +826,19 @@ static const struct {
        {0},
 };
 
+static void
+ipp2p_print_result_tcp(const union ipp2p_addr *saddr, short sport,
+                       const union ipp2p_addr *daddr, short dport,
+                       bool p2p_result, unsigned int hlen)
+{
+       printk("IPP2P.debug:TCP-match: %d from: %pI4:%hu to: %pI4:%hu Length: %u\n",
+              p2p_result, &saddr->ip, sport, &daddr->ip, dport, hlen);
+}
+
 static bool
 ipp2p_mt_tcp(const struct ipt_p2p_info *info, const struct tcphdr *tcph,
              const unsigned char *haystack, unsigned int hlen,
-             const struct iphdr *ip)
+             const struct ipp2p_result_printer *rp)
 {
        size_t tcph_len = tcph->doff * 4;
        bool p2p_result = false;
@@ -838,11 +866,7 @@ ipp2p_mt_tcp(const struct ipt_p2p_info *info, const struct tcphdr *tcph,
                        p2p_result = matchlist[i].function_name(haystack, hlen);
                        if (p2p_result) {
                                if (info->debug)
-                                       printk("IPP2P.debug:TCP-match: %d from: %pI4:%hu to: %pI4:%hu Length: %d\n",
-                                              p2p_result, &ip->saddr,
-                                              ntohs(tcph->source),
-                                              &ip->daddr,
-                                              ntohs(tcph->dest), hlen);
+                                       print_result(rp, p2p_result, hlen);
                                return p2p_result;
                        }
                }
@@ -851,10 +875,19 @@ ipp2p_mt_tcp(const struct ipt_p2p_info *info, const struct tcphdr *tcph,
        return p2p_result;
 }
 
+static void
+ipp2p_print_result_udp(const union ipp2p_addr *saddr, short sport,
+                       const union ipp2p_addr *daddr, short dport,
+                       bool p2p_result, unsigned int hlen)
+{
+       printk("IPP2P.debug:UDP-match: %d from: %pI4:%hu to: %pI4:%hu Length: %u\n",
+              p2p_result, &saddr->ip, sport, &daddr->ip, dport, hlen);
+}
+
 static bool
 ipp2p_mt_udp(const struct ipt_p2p_info *info, const struct udphdr *udph,
              const unsigned char *haystack, unsigned int hlen,
-             const struct iphdr *ip)
+             const struct ipp2p_result_printer *rp)
 {
        size_t udph_len = sizeof(*udph);
        bool p2p_result = false;
@@ -878,11 +911,7 @@ ipp2p_mt_udp(const struct ipt_p2p_info *info, const struct udphdr *udph,
                        p2p_result = udp_list[i].function_name(haystack, hlen);
                        if (p2p_result) {
                                if (info->debug)
-                                       printk("IPP2P.debug:UDP-match: %d from: %pI4:%hu to: %pI4:%hu Length: %d\n",
-                                              p2p_result, &ip->saddr,
-                                              ntohs(udph->source),
-                                              &ip->daddr,
-                                              ntohs(udph->dest), hlen);
+                                       print_result(rp, p2p_result, hlen);
                                return p2p_result;
                        }
                }
@@ -896,6 +925,8 @@ ipp2p_mt(const struct sk_buff *skb, struct xt_action_param *par)
 {
        const struct ipt_p2p_info *info = par->matchinfo;
        const struct iphdr *ip = ip_hdr(skb);
+       struct ipp2p_result_printer printer;
+       union ipp2p_addr saddr, daddr;
        const unsigned char *haystack;  /* packet data */
        unsigned int hlen;              /* packet data length */
 
@@ -916,19 +947,33 @@ ipp2p_mt(const struct sk_buff *skb, struct xt_action_param *par)
        haystack = skb_transport_header(skb);
        hlen     = ntohs(ip->tot_len) - skb_transport_offset(skb);
 
+       saddr.ip = ip->saddr;
+       daddr.ip = ip->daddr;
+
+       printer.saddr = &saddr;
+       printer.daddr = &daddr;
+
        switch (ip->protocol) {
        case IPPROTO_TCP:       /* what to do with a TCP packet */
        {
                const struct tcphdr *tcph = tcp_hdr(skb);
 
-               return ipp2p_mt_tcp(info, tcph, haystack, hlen, ip);
+               printer.sport = ntohs(tcph->source);
+               printer.dport = ntohs(tcph->dest);
+               printer.print = ipp2p_print_result_tcp;
+
+               return ipp2p_mt_tcp(info, tcph, haystack, hlen, &printer);
        }
        case IPPROTO_UDP:       /* what to do with a UDP packet */
        case IPPROTO_UDPLITE:
        {
                const struct udphdr *udph = udp_hdr(skb);
 
-               return ipp2p_mt_udp(info, udph, haystack, hlen, ip);
+               printer.sport = ntohs(udph->source);
+               printer.dport = ntohs(udph->dest);
+               printer.print = ipp2p_print_result_udp;
+
+               return ipp2p_mt_udp(info, udph, haystack, hlen, &printer);
        }
        default:
                return 0;