*** empty log message ***

1 files changed, 522 insertions, 0 deletions

diff --git a/libarptc/libarptc.c b/libarptc/libarptc.c
new file mode 100644
index 0000000..5af7e76
--- /dev/null
+++ b/libarptc/libarptc.c
@@ -0,0 +1,522 @@
+/* Library which manipulates firewall rules.  Version 0.1. */
+
+/* Architecture of firewall rules is as follows:
+ *
+ * Chains go INPUT, FORWARD, OUTPUT then user chains.
+ * Each user chain starts with an ERROR node.
+ * Every chain ends with an unconditional jump: a RETURN for user chains,
+ * and a POLICY for built-ins.
+ */
+
+/* (C)1999 Paul ``Rusty'' Russell - Placed under the GNU GPL (See
+   COPYING for details). */
+
+#include <assert.h>
+#include <string.h>
+#include <errno.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <unistd.h>
+
+#ifdef DEBUG_CONNTRACK
+#define inline
+#endif
+
+#if !defined(__GLIBC__) || (__GLIBC__ < 2)
+typedef unsigned int socklen_t;
+#endif
+
+#include "libarptc/libarptc.h"
+
+#define IP_VERSION	4
+#define IP_OFFSET	0x1FFF
+
+#define STRUCT_ENTRY_TARGET	struct arpt_entry_target
+#define STRUCT_ENTRY		struct arpt_entry
+#define STRUCT_ENTRY_MATCH	struct arpt_entry_match
+#define STRUCT_GETINFO		struct arpt_getinfo
+#define STRUCT_GET_ENTRIES	struct arpt_get_entries
+#define STRUCT_COUNTERS		struct arpt_counters
+#define STRUCT_COUNTERS_INFO	struct arpt_counters_info
+#define STRUCT_STANDARD_TARGET	struct arpt_standard_target
+#define STRUCT_REPLACE		struct arpt_replace
+
+#define STRUCT_TC_HANDLE	struct arptc_handle
+#define TC_HANDLE_T		arptc_handle_t
+
+#define ENTRY_ITERATE		ARPT_ENTRY_ITERATE
+#define TABLE_MAXNAMELEN	ARPT_TABLE_MAXNAMELEN
+#define FUNCTION_MAXNAMELEN	ARPT_FUNCTION_MAXNAMELEN
+
+#define GET_TARGET		arpt_get_target
+
+#define ERROR_TARGET		ARPT_ERROR_TARGET
+#define NUMHOOKS		NF_ARP_NUMHOOKS
+
+#define ARPT_CHAINLABEL		arpt_chainlabel
+
+#define TC_DUMP_ENTRIES		dump_entries
+#define TC_IS_CHAIN		arptc_is_chain
+#define TC_FIRST_CHAIN		arptc_first_chain
+#define TC_NEXT_CHAIN		arptc_next_chain
+#define TC_FIRST_RULE		arptc_first_rule
+#define TC_NEXT_RULE		arptc_next_rule
+#define TC_GET_TARGET		arptc_get_target
+#define TC_BUILTIN		arptc_builtin
+#define TC_GET_POLICY		arptc_get_policy
+#define TC_INSERT_ENTRY		arptc_insert_entry
+#define TC_REPLACE_ENTRY	arptc_replace_entry
+#define TC_APPEND_ENTRY		arptc_append_entry
+#define TC_DELETE_ENTRY		arptc_delete_entry
+#define TC_DELETE_NUM_ENTRY	arptc_delete_num_entry
+#define TC_CHECK_PACKET		arptc_check_packet
+#define TC_FLUSH_ENTRIES	arptc_flush_entries
+#define TC_ZERO_ENTRIES		arptc_zero_entries
+#define TC_READ_COUNTER		arptc_read_counter
+#define TC_ZERO_COUNTER		arptc_zero_counter
+#define TC_SET_COUNTER		arptc_set_counter
+#define TC_CREATE_CHAIN		arptc_create_chain
+#define TC_GET_REFERENCES	arptc_get_references
+#define TC_DELETE_CHAIN		arptc_delete_chain
+#define TC_RENAME_CHAIN		arptc_rename_chain
+#define TC_SET_POLICY		arptc_set_policy
+#define TC_GET_RAW_SOCKET	arptc_get_raw_socket
+#define TC_INIT			arptc_init
+#define TC_COMMIT		arptc_commit
+#define TC_STRERROR		arptc_strerror
+
+#define TC_AF			AF_INET
+#define TC_IPPROTO		IPPROTO_IP
+
+#define SO_SET_REPLACE		ARPT_SO_SET_REPLACE
+#define SO_SET_ADD_COUNTERS	ARPT_SO_SET_ADD_COUNTERS
+#define SO_GET_INFO		ARPT_SO_GET_INFO
+#define SO_GET_ENTRIES		ARPT_SO_GET_ENTRIES
+#define SO_GET_VERSION		ARPT_SO_GET_VERSION
+
+#define STANDARD_TARGET		ARPT_STANDARD_TARGET
+#define LABEL_RETURN		ARPTC_LABEL_RETURN
+#define LABEL_ACCEPT		ARPTC_LABEL_ACCEPT
+#define LABEL_DROP		ARPTC_LABEL_DROP
+#define LABEL_QUEUE		ARPTC_LABEL_QUEUE
+
+#define ALIGN			ARPT_ALIGN
+#define RETURN			ARPT_RETURN
+
+#include "libarptc_incl.c"
+
+#define IP_PARTS_NATIVE(n)			\
+(unsigned int)((n)>>24)&0xFF,			\
+(unsigned int)((n)>>16)&0xFF,			\
+(unsigned int)((n)>>8)&0xFF,			\
+(unsigned int)((n)&0xFF)
+
+#define IP_PARTS(n) IP_PARTS_NATIVE(ntohl(n))
+
+int
+dump_entry(STRUCT_ENTRY *e, const TC_HANDLE_T handle)
+{
+	size_t i;
+	STRUCT_ENTRY_TARGET *t;
+
+	printf("Entry %u (%lu):\n", entry2index(handle, e),
+	       entry2offset(handle, e));
+	printf("SRC IP: %u.%u.%u.%u/%u.%u.%u.%u\n",
+	       IP_PARTS(e->arp.src.s_addr),IP_PARTS(e->arp.smsk.s_addr));
+	printf("DST IP: %u.%u.%u.%u/%u.%u.%u.%u\n",
+	       IP_PARTS(e->arp.tgt.s_addr),IP_PARTS(e->arp.tmsk.s_addr));
+	printf("Interface: `%s'/", e->arp.iniface);
+	for (i = 0; i < IFNAMSIZ; i++)
+		printf("%c", e->arp.iniface_mask[i] ? 'X' : '.');
+	printf("to `%s'/", e->arp.outiface);
+	for (i = 0; i < IFNAMSIZ; i++)
+		printf("%c", e->arp.outiface_mask[i] ? 'X' : '.');
+	printf("Flags: %02X\n", e->arp.flags);
+	printf("Invflags: %02X\n", e->arp.invflags);
+	printf("Counters: %llu packets, %llu bytes\n",
+	       e->counters.pcnt, e->counters.bcnt);
+/*
+	printf("Cache: %08X ", e->nfcache);
+	if (e->nfcache & NFC_ALTERED) printf("ALTERED ");
+	if (e->nfcache & NFC_UNKNOWN) printf("UNKNOWN ");
+	if (e->nfcache & NFC_IP_SRC) printf("IP_SRC ");
+	if (e->nfcache & NFC_IP_DST) printf("IP_DST ");
+	if (e->nfcache & NFC_IP_IF_IN) printf("IP_IF_IN ");
+	if (e->nfcache & NFC_IP_IF_OUT) printf("IP_IF_OUT ");
+	if (e->nfcache & NFC_IP_TOS) printf("IP_TOS ");
+	if (e->nfcache & NFC_IP_PROTO) printf("IP_PROTO ");
+	if (e->nfcache & NFC_IP_OPTIONS) printf("IP_OPTIONS ");
+	if (e->nfcache & NFC_IP_TCPFLAGS) printf("IP_TCPFLAGS ");
+	if (e->nfcache & NFC_IP_SRC_PT) printf("IP_SRC_PT ");
+	if (e->nfcache & NFC_IP_DST_PT) printf("IP_DST_PT ");
+	if (e->nfcache & NFC_IP_PROTO_UNKNOWN) printf("IP_PROTO_UNKNOWN ");
+*/
+	printf("\n");
+
+/*
+	ARPT_MATCH_ITERATE(e, print_match);
+*/
+
+	t = GET_TARGET(e);
+	printf("Target name: `%s' [%u]\n", t->u.user.name, t->u.target_size);
+	if (strcmp(t->u.user.name, STANDARD_TARGET) == 0) {
+		int pos = *(int *)t->data;
+		if (pos < 0)
+			printf("verdict=%s\n",
+			       pos == -NF_ACCEPT-1 ? "NF_ACCEPT"
+			       : pos == -NF_DROP-1 ? "NF_DROP"
+			       : pos == -NF_QUEUE-1 ? "NF_QUEUE"
+			       : pos == RETURN ? "RETURN"
+			       : "UNKNOWN");
+		else
+			printf("verdict=%u\n", pos);
+	} else if (strcmp(t->u.user.name, ARPT_ERROR_TARGET) == 0)
+		printf("error=`%s'\n", t->data);
+
+	printf("\n");
+	return 0;
+}
+
+static int
+is_same(const STRUCT_ENTRY *a, const STRUCT_ENTRY *b, unsigned char *matchmask)
+{
+	unsigned int i;
+	STRUCT_ENTRY_TARGET *ta, *tb;
+	unsigned char *mptr;
+
+	/* Always compare head structures: ignore mask here. */
+	if (a->arp.src.s_addr != b->arp.src.s_addr
+	    || a->arp.tgt.s_addr != b->arp.tgt.s_addr
+	    || a->arp.smsk.s_addr != b->arp.smsk.s_addr
+	    || a->arp.tmsk.s_addr != b->arp.tmsk.s_addr
+	    || a->arp.arhln != b->arp.arhln
+	    || a->arp.arhln_mask != b->arp.arhln_mask
+	    || a->arp.arpop != b->arp.arpop
+	    || a->arp.arpop_mask != b->arp.arpop_mask
+	    || a->arp.arhrd != b->arp.arhrd
+	    || a->arp.arhrd_mask != b->arp.arhrd_mask
+	    || a->arp.arpro != b->arp.arpro
+	    || a->arp.arpro_mask != b->arp.arpro_mask
+	    || a->arp.flags != b->arp.flags
+	    || a->arp.invflags != b->arp.invflags)
+		return 0;
+
+	for (i = 0; i < ARPT_DEV_ADDR_LEN_MAX; i++) {
+		if (a->arp.src_devaddr.addr[i] != b->arp.src_devaddr.addr[i] ||
+		    a->arp.src_devaddr.mask[i] != b->arp.src_devaddr.mask[i])
+			return 0;
+		if (a->arp.tgt_devaddr.addr[i] != b->arp.tgt_devaddr.addr[i] ||
+		    a->arp.tgt_devaddr.mask[i] != b->arp.tgt_devaddr.mask[i])
+			return 0;
+	}
+
+	for (i = 0; i < IFNAMSIZ; i++) {
+		if (a->arp.iniface_mask[i] != b->arp.iniface_mask[i])
+			return 0;
+		if ((a->arp.iniface[i] & a->arp.iniface_mask[i])
+		    != (b->arp.iniface[i] & b->arp.iniface_mask[i]))
+			return 0;
+		if (a->arp.outiface_mask[i] != b->arp.outiface_mask[i])
+			return 0;
+		if ((a->arp.outiface[i] & a->arp.outiface_mask[i])
+		    != (b->arp.outiface[i] & b->arp.outiface_mask[i]))
+			return 0;
+	}
+
+	if (/* a->nfcache != b->nfcache
+	    || */a->target_offset != b->target_offset
+	    || a->next_offset != b->next_offset)
+		return 0;
+
+	mptr = matchmask + sizeof(STRUCT_ENTRY);
+/*
+	if (ARPT_MATCH_ITERATE(a, match_different, a->elems, b->elems, &mptr))
+		return 0;
+*/
+
+	ta = GET_TARGET((STRUCT_ENTRY *)a);
+	tb = GET_TARGET((STRUCT_ENTRY *)b);
+	if (ta->u.target_size != tb->u.target_size)
+		return 0;
+	if (strcmp(ta->u.user.name, tb->u.user.name) != 0)
+		return 0;
+
+	mptr += sizeof(*ta);
+	if (target_different(ta->data, tb->data,
+			     ta->u.target_size - sizeof(*ta), mptr))
+		return 0;
+
+   	return 1;
+}
+
+/***************************** DEBUGGING ********************************/
+static inline int
+unconditional(const struct arpt_arp *arp)
+{
+	unsigned int i;
+
+	for (i = 0; i < sizeof(*arp)/sizeof(u_int32_t); i++)
+		if (((u_int32_t *)arp)[i])
+			return 0;
+
+	return 1;
+}
+
+/*
+static inline int
+check_match(const STRUCT_ENTRY_MATCH *m, unsigned int *off)
+{
+	assert(m->u.match_size >= sizeof(STRUCT_ENTRY_MATCH));
+	assert(ALIGN(m->u.match_size) == m->u.match_size);
+
+	(*off) += m->u.match_size;
+	return 0;
+}
+*/
+
+static inline int
+check_entry(const STRUCT_ENTRY *e, unsigned int *i, unsigned int *off,
+	    unsigned int user_offset, int *was_return,
+	    TC_HANDLE_T h)
+{
+	unsigned int toff;
+	STRUCT_STANDARD_TARGET *t;
+
+	assert(e->target_offset >= sizeof(STRUCT_ENTRY));
+	assert(e->next_offset >= e->target_offset
+	       + sizeof(STRUCT_ENTRY_TARGET));
+	toff = sizeof(STRUCT_ENTRY);
+/*
+	ARPT_MATCH_ITERATE(e, check_match, &toff);
+*/
+
+	assert(toff == e->target_offset);
+
+	t = (STRUCT_STANDARD_TARGET *)
+		GET_TARGET((STRUCT_ENTRY *)e);
+	/* next_offset will have to be multiple of entry alignment. */
+	assert(e->next_offset == ALIGN(e->next_offset));
+	assert(e->target_offset == ALIGN(e->target_offset));
+	assert(t->target.u.target_size == ALIGN(t->target.u.target_size));
+	assert(!TC_IS_CHAIN(t->target.u.user.name, h));
+
+	if (strcmp(t->target.u.user.name, STANDARD_TARGET) == 0) {
+		assert(t->target.u.target_size
+		       == ALIGN(sizeof(STRUCT_STANDARD_TARGET)));
+
+		assert(t->verdict == -NF_DROP-1
+		       || t->verdict == -NF_ACCEPT-1
+		       || t->verdict == RETURN
+		       || t->verdict < (int)h->entries.size);
+
+		if (t->verdict >= 0) {
+			STRUCT_ENTRY *te = get_entry(h, t->verdict);
+			int idx;
+
+			idx = entry2index(h, te);
+			assert(strcmp(GET_TARGET(te)->u.user.name,
+				      ARPT_ERROR_TARGET)
+			       != 0);
+			assert(te != e);
+
+			/* Prior node must be error node, or this node. */
+			assert(t->verdict == entry2offset(h, e)+e->next_offset
+			       || strcmp(GET_TARGET(index2entry(h, idx-1))
+					 ->u.user.name, ARPT_ERROR_TARGET)
+			       == 0);
+		}
+
+		if (t->verdict == RETURN
+		    && unconditional(&e->arp)
+		    && e->target_offset == sizeof(*e))
+			*was_return = 1;
+		else
+			*was_return = 0;
+	} else if (strcmp(t->target.u.user.name, ARPT_ERROR_TARGET) == 0) {
+		assert(t->target.u.target_size
+		       == ALIGN(sizeof(struct arpt_error_target)));
+
+		/* If this is in user area, previous must have been return */
+		if (*off > user_offset)
+			assert(*was_return);
+
+		*was_return = 0;
+	}
+	else *was_return = 0;
+
+	if (*off == user_offset)
+		assert(strcmp(t->target.u.user.name, ARPT_ERROR_TARGET) == 0);
+
+	(*off) += e->next_offset;
+	(*i)++;
+	return 0;
+}
+
+#ifdef ARPTC_DEBUG
+/* Do every conceivable sanity check on the handle */
+static void
+do_check(TC_HANDLE_T h, unsigned int line)
+{
+	unsigned int i, n;
+	unsigned int user_offset; /* Offset of first user chain */
+	int was_return;
+
+	assert(h->changed == 0 || h->changed == 1);
+	if (strcmp(h->info.name, "filter") == 0) {
+		assert(h->info.valid_hooks
+		       == (1 << NF_IP_LOCAL_IN
+			   | 1 << NF_IP_FORWARD
+			   | 1 << NF_IP_LOCAL_OUT));
+
+		/* Hooks should be first three */
+		assert(h->info.hook_entry[NF_IP_LOCAL_IN] == 0);
+
+		n = get_chain_end(h, 0);
+		n += get_entry(h, n)->next_offset;
+		assert(h->info.hook_entry[NF_IP_FORWARD] == n);
+
+		n = get_chain_end(h, n);
+		n += get_entry(h, n)->next_offset;
+		assert(h->info.hook_entry[NF_IP_LOCAL_OUT] == n);
+
+		user_offset = h->info.hook_entry[NF_IP_LOCAL_OUT];
+	} else if (strcmp(h->info.name, "nat") == 0) {
+		assert((h->info.valid_hooks
+		        == (1 << NF_IP_PRE_ROUTING
+			    | 1 << NF_IP_POST_ROUTING
+			    | 1 << NF_IP_LOCAL_OUT)) ||
+		       (h->info.valid_hooks
+			== (1 << NF_IP_PRE_ROUTING
+			    | 1 << NF_IP_LOCAL_IN
+			    | 1 << NF_IP_POST_ROUTING
+			    | 1 << NF_IP_LOCAL_OUT)));
+
+		assert(h->info.hook_entry[NF_IP_PRE_ROUTING] == 0);
+
+		n = get_chain_end(h, 0);
+
+		n += get_entry(h, n)->next_offset;
+		assert(h->info.hook_entry[NF_IP_POST_ROUTING] == n);
+		n = get_chain_end(h, n);
+
+		n += get_entry(h, n)->next_offset;
+		assert(h->info.hook_entry[NF_IP_LOCAL_OUT] == n);
+		user_offset = h->info.hook_entry[NF_IP_LOCAL_OUT];
+
+		if (h->info.valid_hooks & (1 << NF_IP_LOCAL_IN)) {
+			n = get_chain_end(h, n);
+			n += get_entry(h, n)->next_offset;
+			assert(h->info.hook_entry[NF_IP_LOCAL_IN] == n);
+			user_offset = h->info.hook_entry[NF_IP_LOCAL_IN];
+		}
+
+	} else if (strcmp(h->info.name, "mangle") == 0) {
+		/* This code is getting ugly because linux < 2.4.18-pre6 had
+		 * two mangle hooks, linux >= 2.4.18-pre6 has five mangle hooks
+		 * */
+		assert((h->info.valid_hooks
+			== (1 << NF_IP_PRE_ROUTING
+			    | 1 << NF_IP_LOCAL_OUT)) || 
+		       (h->info.valid_hooks
+			== (1 << NF_IP_PRE_ROUTING
+			    | 1 << NF_IP_LOCAL_IN
+			    | 1 << NF_IP_FORWARD
+			    | 1 << NF_IP_LOCAL_OUT
+			    | 1 << NF_IP_POST_ROUTING)));
+
+		/* Hooks should be first five */
+		assert(h->info.hook_entry[NF_IP_PRE_ROUTING] == 0);
+
+		n = get_chain_end(h, 0);
+
+		if (h->info.valid_hooks & (1 << NF_IP_LOCAL_IN)) {
+			n += get_entry(h, n)->next_offset;
+			assert(h->info.hook_entry[NF_IP_LOCAL_IN] == n);
+			n = get_chain_end(h, n);
+		}
+
+		if (h->info.valid_hooks & (1 << NF_IP_FORWARD)) {
+			n += get_entry(h, n)->next_offset;
+			assert(h->info.hook_entry[NF_IP_FORWARD] == n);
+			n = get_chain_end(h, n);
+		}
+
+		n += get_entry(h, n)->next_offset;
+		assert(h->info.hook_entry[NF_IP_LOCAL_OUT] == n);
+		user_offset = h->info.hook_entry[NF_IP_LOCAL_OUT];
+
+		if (h->info.valid_hooks & (1 << NF_IP_POST_ROUTING)) {
+			n = get_chain_end(h, n);
+			n += get_entry(h, n)->next_offset;
+			assert(h->info.hook_entry[NF_IP_POST_ROUTING] == n);
+			user_offset = h->info.hook_entry[NF_IP_POST_ROUTING];
+		}
+
+#ifdef NF_IP_DROPPING
+	} else if (strcmp(h->info.name, "drop") == 0) {
+		assert(h->info.valid_hooks == (1 << NF_IP_DROPPING));
+
+		/* Hook should be first */
+		assert(h->info.hook_entry[NF_IP_DROPPING] == 0);
+		user_offset = 0;
+#endif
+	} else {
+		fprintf(stderr, "Unknown table `%s'\n", h->info.name);
+		abort();
+	}
+
+	/* User chain == end of last builtin + policy entry */
+	user_offset = get_chain_end(h, user_offset);
+	user_offset += get_entry(h, user_offset)->next_offset;
+
+	/* Overflows should be end of entry chains, and unconditional
+           policy nodes. */
+	for (i = 0; i < NUMHOOKS; i++) {
+		STRUCT_ENTRY *e;
+		STRUCT_STANDARD_TARGET *t;
+
+		if (!(h->info.valid_hooks & (1 << i)))
+			continue;
+		assert(h->info.underflow[i]
+		       == get_chain_end(h, h->info.hook_entry[i]));
+
+		e = get_entry(h, get_chain_end(h, h->info.hook_entry[i]));
+		assert(unconditional(&e->ip));
+		assert(e->target_offset == sizeof(*e));
+		t = (STRUCT_STANDARD_TARGET *)GET_TARGET(e);
+		assert(t->target.u.target_size == ALIGN(sizeof(*t)));
+		assert(e->next_offset == sizeof(*e) + ALIGN(sizeof(*t)));
+
+		assert(strcmp(t->target.u.user.name, STANDARD_TARGET)==0);
+		assert(t->verdict == -NF_DROP-1 || t->verdict == -NF_ACCEPT-1);
+
+		/* Hooks and underflows must be valid entries */
+		entry2index(h, get_entry(h, h->info.hook_entry[i]));
+		entry2index(h, get_entry(h, h->info.underflow[i]));
+	}
+
+	assert(h->info.size
+	       >= h->info.num_entries * (sizeof(STRUCT_ENTRY)
+					 +sizeof(STRUCT_STANDARD_TARGET)));
+
+	assert(h->entries.size
+	       >= (h->new_number
+		   * (sizeof(STRUCT_ENTRY)
+		      + sizeof(STRUCT_STANDARD_TARGET))));
+	assert(strcmp(h->info.name, h->entries.name) == 0);
+
+	i = 0; n = 0;
+	was_return = 0;
+	/* Check all the entries. */
+	ENTRY_ITERATE(h->entries.entrytable, h->entries.size,
+		      check_entry, &i, &n, user_offset, &was_return, h);
+
+	assert(i == h->new_number);
+	assert(n == h->entries.size);
+
+	/* Final entry must be error node */
+	assert(strcmp(GET_TARGET(index2entry(h, h->new_number-1))
+		      ->u.user.name,
+		      ERROR_TARGET) == 0);
+}
+#endif /*ARPTC_DEBUG*/