target/linux/generic-2.4/patches/619-nefilter_multiport_backport.patch

   1 diff -urN linux.old/include/linux/netfilter_ipv4/ipt_multiport.h linux.dev/include/linux/netfilter_ipv4/ipt_multiport.h
   2 --- linux.old/include/linux/netfilter_ipv4/ipt_multiport.h      2000-12-11 22:31:30.000000000 +0100
   3 +++ linux.dev/include/linux/netfilter_ipv4/ipt_multiport.h      2006-02-04 05:05:51.928476750 +0100
   4 @@ -18,4 +18,13 @@
   5         u_int8_t count;                         /* Number of ports */
   6         u_int16_t ports[IPT_MULTI_PORTS];       /* Ports */
   7  };
   8 +
   9 +struct ipt_multiport_v1
  10 +{
  11 +       u_int8_t flags;                         /* Type of comparison */
  12 +       u_int8_t count;                         /* Number of ports */
  13 +       u_int16_t ports[IPT_MULTI_PORTS];       /* Ports */
  14 +       u_int8_t pflags[IPT_MULTI_PORTS];       /* Port flags */
  15 +       u_int8_t invert;                        /* Invert flag */
  16 +};
  17  #endif /*_IPT_MULTIPORT_H*/
  18 diff -urN linux.old/net/ipv4/netfilter/ipt_multiport.c linux.dev/net/ipv4/netfilter/ipt_multiport.c
  19 --- linux.old/net/ipv4/netfilter/ipt_multiport.c        2003-06-13 16:51:39.000000000 +0200
  20 +++ linux.dev/net/ipv4/netfilter/ipt_multiport.c        2006-02-04 05:05:03.701462750 +0100
  21 @@ -1,5 +1,14 @@
  22  /* Kernel module to match one of a list of TCP/UDP ports: ports are in
  23     the same place so we can treat them as equal. */
  24 +
  25 +/* (C) 1999-2001 Paul `Rusty' Russell
  26 + * (C) 2002-2004 Netfilter Core Team <coreteam@netfilter.org>
  27 + *
  28 + * This program is free software; you can redistribute it and/or modify
  29 + * it under the terms of the GNU General Public License version 2 as
  30 + * published by the Free Software Foundation.
  31 + */
  32 +
  33  #include <linux/module.h>
  34  #include <linux/types.h>
  35  #include <linux/udp.h>
  36 @@ -8,6 +17,10 @@
  37  #include <linux/netfilter_ipv4/ipt_multiport.h>
  38  #include <linux/netfilter_ipv4/ip_tables.h>
  39
  40 +MODULE_LICENSE("GPL");
  41 +MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>");
  42 +MODULE_DESCRIPTION("iptables multiple port match module");
  43 +
  44  #if 0
  45  #define duprintf(format, args...) printk(format , ## args)
  46  #else
  47 @@ -33,34 +46,109 @@
  48         return 0;
  49  }
  50
  51 +/* Returns 1 if the port is matched by the test, 0 otherwise. */
  52 +static inline int
  53 +ports_match_v1(const struct ipt_multiport_v1 *minfo,
  54 +              u_int16_t src, u_int16_t dst)
  55 +{
  56 +       unsigned int i;
  57 +       u_int16_t s, e;
  58 +
  59 +       for (i=0; i < minfo->count; i++) {
  60 +               s = minfo->ports[i];
  61 +
  62 +               if (minfo->pflags[i]) {
  63 +                       /* range port matching */
  64 +                       e = minfo->ports[++i];
  65 +                       duprintf("src or dst matches with %d-%d?\n", s, e);
  66 +
  67 +                       if (minfo->flags == IPT_MULTIPORT_SOURCE
  68 +                           && src >= s && src <= e)
  69 +                               return 1 ^ minfo->invert;
  70 +                       if (minfo->flags == IPT_MULTIPORT_DESTINATION
  71 +                           && dst >= s && dst <= e)
  72 +                               return 1 ^ minfo->invert;
  73 +                       if (minfo->flags == IPT_MULTIPORT_EITHER
  74 +                           && ((dst >= s && dst <= e)
  75 +                               || (src >= s && src <= e)))
  76 +                               return 1 ^ minfo->invert;
  77 +               } else {
  78 +                       /* exact port matching */
  79 +                       duprintf("src or dst matches with %d?\n", s);
  80 +
  81 +                       if (minfo->flags == IPT_MULTIPORT_SOURCE
  82 +                           && src == s)
  83 +                               return 1 ^ minfo->invert;
  84 +                       if (minfo->flags == IPT_MULTIPORT_DESTINATION
  85 +                           && dst == s)
  86 +                               return 1 ^ minfo->invert;
  87 +                       if (minfo->flags == IPT_MULTIPORT_EITHER
  88 +                           && (src == s || dst == s))
  89 +                               return 1 ^ minfo->invert;
  90 +               }
  91 +       }
  92 +
  93 +       return minfo->invert;
  94 +}
  95 +
  96  static int
  97  match(const struct sk_buff *skb,
  98        const struct net_device *in,
  99        const struct net_device *out,
 100        const void *matchinfo,
 101        int offset,
 102 -      const void *hdr,
 103 -      u_int16_t datalen,
 104        int *hotdrop)
 105  {
 106 -       const struct udphdr *udp = hdr;
 107 +       u16 _ports[2], *pptr;
 108         const struct ipt_multiport *multiinfo = matchinfo;
 109
 110 -       /* Must be big enough to read ports. */
 111 -       if (offset == 0 && datalen < sizeof(struct udphdr)) {
 112 +       if (offset)
 113 +               return 0;
 114 +
 115 +       pptr = skb_header_pointer(skb, skb->nh.iph->ihl * 4,
 116 +                                 sizeof(_ports), _ports);
 117 +       if (pptr == NULL) {
 118                 /* We've been asked to examine this packet, and we
 119 -                  can't.  Hence, no choice but to drop. */
 120 -                       duprintf("ipt_multiport:"
 121 -                                " Dropping evil offset=0 tinygram.\n");
 122 -                       *hotdrop = 1;
 123 -                       return 0;
 124 +                * can't.  Hence, no choice but to drop.
 125 +                */
 126 +               duprintf("ipt_multiport:"
 127 +                        " Dropping evil offset=0 tinygram.\n");
 128 +               *hotdrop = 1;
 129 +               return 0;
 130         }
 131
 132 -       /* Must not be a fragment. */
 133 -       return !offset
 134 -               && ports_match(multiinfo->ports,
 135 -                              multiinfo->flags, multiinfo->count,
 136 -                              ntohs(udp->source), ntohs(udp->dest));
 137 +       return ports_match(multiinfo->ports,
 138 +                          multiinfo->flags, multiinfo->count,
 139 +                          ntohs(pptr[0]), ntohs(pptr[1]));
 140 +}
 141 +
 142 +static int
 143 +match_v1(const struct sk_buff *skb,
 144 +        const struct net_device *in,
 145 +        const struct net_device *out,
 146 +        const void *matchinfo,
 147 +        int offset,
 148 +        int *hotdrop)
 149 +{
 150 +       u16 _ports[2], *pptr;
 151 +       const struct ipt_multiport_v1 *multiinfo = matchinfo;
 152 +
 153 +       if (offset)
 154 +               return 0;
 155 +
 156 +       pptr = skb_header_pointer(skb, skb->nh.iph->ihl * 4,
 157 +                                 sizeof(_ports), _ports);
 158 +       if (pptr == NULL) {
 159 +               /* We've been asked to examine this packet, and we
 160 +                * can't.  Hence, no choice but to drop.
 161 +                */
 162 +               duprintf("ipt_multiport:"
 163 +                        " Dropping evil offset=0 tinygram.\n");
 164 +               *hotdrop = 1;
 165 +               return 0;
 166 +       }
 167 +
 168 +       return ports_match_v1(multiinfo, ntohs(pptr[0]), ntohs(pptr[1]));
 169  }
 170
 171  /* Called when user tries to insert an entry of this type. */
 172 @@ -71,34 +159,54 @@
 173            unsigned int matchsize,
 174            unsigned int hook_mask)
 175  {
 176 -       const struct ipt_multiport *multiinfo = matchinfo;
 177 -
 178 -       if (matchsize != IPT_ALIGN(sizeof(struct ipt_multiport)))
 179 -               return 0;
 180 +       return (matchsize == IPT_ALIGN(sizeof(struct ipt_multiport)));
 181 +}
 182
 183 -       /* Must specify proto == TCP/UDP, no unknown flags or bad count */
 184 -       return (ip->proto == IPPROTO_TCP || ip->proto == IPPROTO_UDP)
 185 -               && !(ip->invflags & IPT_INV_PROTO)
 186 -               && matchsize == IPT_ALIGN(sizeof(struct ipt_multiport))
 187 -               && (multiinfo->flags == IPT_MULTIPORT_SOURCE
 188 -                   || multiinfo->flags == IPT_MULTIPORT_DESTINATION
 189 -                   || multiinfo->flags == IPT_MULTIPORT_EITHER)
 190 -               && multiinfo->count <= IPT_MULTI_PORTS;
 191 +static int
 192 +checkentry_v1(const char *tablename,
 193 +             const struct ipt_ip *ip,
 194 +             void *matchinfo,
 195 +             unsigned int matchsize,
 196 +             unsigned int hook_mask)
 197 +{
 198 +       return (matchsize == IPT_ALIGN(sizeof(struct ipt_multiport_v1)));
 199  }
 200
 201 -static struct ipt_match multiport_match
 202 -= { { NULL, NULL }, "multiport", &match, &checkentry, NULL, THIS_MODULE };
 203 +static struct ipt_match multiport_match = {
 204 +       .name           = "multiport",
 205 +       .revision       = 0,
 206 +       .match          = &match,
 207 +       .checkentry     = &checkentry,
 208 +       .me             = THIS_MODULE,
 209 +};
 210 +
 211 +static struct ipt_match multiport_match_v1 = {
 212 +       .name           = "multiport",
 213 +       .revision       = 1,
 214 +       .match          = &match_v1,
 215 +       .checkentry     = &checkentry_v1,
 216 +       .me             = THIS_MODULE,
 217 +};
 218
 219  static int __init init(void)
 220  {
 221 -       return ipt_register_match(&multiport_match);
 222 +       int err;
 223 +
 224 +       err = ipt_register_match(&multiport_match);
 225 +       if (!err) {
 226 +               err = ipt_register_match(&multiport_match_v1);
 227 +               if (err)
 228 +                       ipt_unregister_match(&multiport_match);
 229 +       }
 230 +
 231 +       return err;
 232  }
 233
 234  static void __exit fini(void)
 235  {
 236         ipt_unregister_match(&multiport_match);
 237 +       ipt_unregister_match(&multiport_match_v1);
 238  }
 239
 240  module_init(init);
 241  module_exit(fini);
 242 -MODULE_LICENSE("GPL");