diff options
Diffstat (limited to 'net/ipv4/netfilter/ipt_sctp.c')
-rw-r--r-- | net/ipv4/netfilter/ipt_sctp.c | 203 |
1 files changed, 0 insertions, 203 deletions
diff --git a/net/ipv4/netfilter/ipt_sctp.c b/net/ipv4/netfilter/ipt_sctp.c deleted file mode 100644 index fe2b327..0000000 --- a/net/ipv4/netfilter/ipt_sctp.c +++ /dev/null @@ -1,203 +0,0 @@ -#include <linux/module.h> -#include <linux/skbuff.h> -#include <net/ip.h> -#include <linux/sctp.h> - -#include <linux/netfilter_ipv4/ip_tables.h> -#include <linux/netfilter_ipv4/ipt_sctp.h> - -#ifdef DEBUG_SCTP -#define duprintf(format, args...) printk(format , ## args) -#else -#define duprintf(format, args...) -#endif - -#define SCCHECK(cond, option, flag, invflag) (!((flag) & (option)) \ - || (!!((invflag) & (option)) ^ (cond))) - -static int -match_flags(const struct ipt_sctp_flag_info *flag_info, - const int flag_count, - u_int8_t chunktype, - u_int8_t chunkflags) -{ - int i; - - for (i = 0; i < flag_count; i++) { - if (flag_info[i].chunktype == chunktype) { - return (chunkflags & flag_info[i].flag_mask) == flag_info[i].flag; - } - } - - return 1; -} - -static int -match_packet(const struct sk_buff *skb, - const u_int32_t *chunkmap, - int chunk_match_type, - const struct ipt_sctp_flag_info *flag_info, - const int flag_count, - int *hotdrop) -{ - int offset; - u_int32_t chunkmapcopy[256 / sizeof (u_int32_t)]; - sctp_chunkhdr_t _sch, *sch; - -#ifdef DEBUG_SCTP - int i = 0; -#endif - - if (chunk_match_type == SCTP_CHUNK_MATCH_ALL) { - SCTP_CHUNKMAP_COPY(chunkmapcopy, chunkmap); - } - - offset = skb->nh.iph->ihl * 4 + sizeof (sctp_sctphdr_t); - do { - sch = skb_header_pointer(skb, offset, sizeof(_sch), &_sch); - if (sch == NULL) { - duprintf("Dropping invalid SCTP packet.\n"); - *hotdrop = 1; - return 0; - } - - duprintf("Chunk num: %d\toffset: %d\ttype: %d\tlength: %d\tflags: %x\n", - ++i, offset, sch->type, htons(sch->length), sch->flags); - - offset += (htons(sch->length) + 3) & ~3; - - duprintf("skb->len: %d\toffset: %d\n", skb->len, offset); - - if (SCTP_CHUNKMAP_IS_SET(chunkmap, sch->type)) { - switch (chunk_match_type) { - case SCTP_CHUNK_MATCH_ANY: - if (match_flags(flag_info, flag_count, - sch->type, sch->flags)) { - return 1; - } - break; - - case SCTP_CHUNK_MATCH_ALL: - if (match_flags(flag_info, flag_count, - sch->type, sch->flags)) { - SCTP_CHUNKMAP_CLEAR(chunkmapcopy, sch->type); - } - break; - - case SCTP_CHUNK_MATCH_ONLY: - if (!match_flags(flag_info, flag_count, - sch->type, sch->flags)) { - return 0; - } - break; - } - } else { - switch (chunk_match_type) { - case SCTP_CHUNK_MATCH_ONLY: - return 0; - } - } - } while (offset < skb->len); - - switch (chunk_match_type) { - case SCTP_CHUNK_MATCH_ALL: - return SCTP_CHUNKMAP_IS_CLEAR(chunkmap); - case SCTP_CHUNK_MATCH_ANY: - return 0; - case SCTP_CHUNK_MATCH_ONLY: - return 1; - } - - /* This will never be reached, but required to stop compiler whine */ - return 0; -} - -static int -match(const struct sk_buff *skb, - const struct net_device *in, - const struct net_device *out, - const void *matchinfo, - int offset, - int *hotdrop) -{ - const struct ipt_sctp_info *info; - sctp_sctphdr_t _sh, *sh; - - info = (const struct ipt_sctp_info *)matchinfo; - - if (offset) { - duprintf("Dropping non-first fragment.. FIXME\n"); - return 0; - } - - sh = skb_header_pointer(skb, skb->nh.iph->ihl*4, sizeof(_sh), &_sh); - if (sh == NULL) { - duprintf("Dropping evil TCP offset=0 tinygram.\n"); - *hotdrop = 1; - return 0; - } - duprintf("spt: %d\tdpt: %d\n", ntohs(sh->source), ntohs(sh->dest)); - - return SCCHECK(((ntohs(sh->source) >= info->spts[0]) - && (ntohs(sh->source) <= info->spts[1])), - IPT_SCTP_SRC_PORTS, info->flags, info->invflags) - && SCCHECK(((ntohs(sh->dest) >= info->dpts[0]) - && (ntohs(sh->dest) <= info->dpts[1])), - IPT_SCTP_DEST_PORTS, info->flags, info->invflags) - && SCCHECK(match_packet(skb, info->chunkmap, info->chunk_match_type, - info->flag_info, info->flag_count, - hotdrop), - IPT_SCTP_CHUNK_TYPES, info->flags, info->invflags); -} - -static int -checkentry(const char *tablename, - const struct ipt_ip *ip, - void *matchinfo, - unsigned int matchsize, - unsigned int hook_mask) -{ - const struct ipt_sctp_info *info; - - info = (const struct ipt_sctp_info *)matchinfo; - - return ip->proto == IPPROTO_SCTP - && !(ip->invflags & IPT_INV_PROTO) - && matchsize == IPT_ALIGN(sizeof(struct ipt_sctp_info)) - && !(info->flags & ~IPT_SCTP_VALID_FLAGS) - && !(info->invflags & ~IPT_SCTP_VALID_FLAGS) - && !(info->invflags & ~info->flags) - && ((!(info->flags & IPT_SCTP_CHUNK_TYPES)) || - (info->chunk_match_type & - (SCTP_CHUNK_MATCH_ALL - | SCTP_CHUNK_MATCH_ANY - | SCTP_CHUNK_MATCH_ONLY))); -} - -static struct ipt_match sctp_match = -{ - .list = { NULL, NULL}, - .name = "sctp", - .match = &match, - .checkentry = &checkentry, - .destroy = NULL, - .me = THIS_MODULE -}; - -static int __init init(void) -{ - return ipt_register_match(&sctp_match); -} - -static void __exit fini(void) -{ - ipt_unregister_match(&sctp_match); -} - -module_init(init); -module_exit(fini); - -MODULE_LICENSE("GPL"); -MODULE_AUTHOR("Kiran Kumar Immidi"); -MODULE_DESCRIPTION("Match for SCTP protocol packets"); - |