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authorjkh <jkh@FreeBSD.org>1994-11-17 09:50:30 +0000
committerjkh <jkh@FreeBSD.org>1994-11-17 09:50:30 +0000
commit74b1e0b0171782131972d6a6ac3730a9c6e69b1d (patch)
tree7a127d4516be1a12e1ba2923e5a77238be7589ba /sbin/ipfw
parent06d8605f45bc9c68d76ef264f9b08a30e0addf7c (diff)
downloadFreeBSD-src-74b1e0b0171782131972d6a6ac3730a9c6e69b1d.zip
FreeBSD-src-74b1e0b0171782131972d6a6ac3730a9c6e69b1d.tar.gz
New man pages from Ugen. Delete my old, first attempt. I only hope
that the english in Ugen's two replacement pages is not too impenetrable! :-) [Note: Poul - please pull these into the BETA branch along with the other firewall changes] Submitted by: ugen
Diffstat (limited to 'sbin/ipfw')
-rw-r--r--sbin/ipfw/Makefile4
-rw-r--r--sbin/ipfw/ipfirewall.4206
-rw-r--r--sbin/ipfw/ipfw.8128
3 files changed, 338 insertions, 0 deletions
diff --git a/sbin/ipfw/Makefile b/sbin/ipfw/Makefile
index 1188c0a..be403fc 100644
--- a/sbin/ipfw/Makefile
+++ b/sbin/ipfw/Makefile
@@ -2,4 +2,8 @@ PROG= ipfw
DPADD= ${LIBKVM}
LDADD= -lkvm
+MAN4= ipfirewall.4
+MLINKS= ipfirewall.4 ipacct.4 ipfirewall.4 ipfw.4 ipfirewall.4 ipaccounting.4
+MAN8= ipfw.8
+
.include <bsd.prog.mk>
diff --git a/sbin/ipfw/ipfirewall.4 b/sbin/ipfw/ipfirewall.4
new file mode 100644
index 0000000..e8aaa7c
--- /dev/null
+++ b/sbin/ipfw/ipfirewall.4
@@ -0,0 +1,206 @@
+.Dd November 16, 1994
+.Dt IPFW(4)/IPACCT 4
+.Os
+.Sh NAME
+
+ipfirewall,ipfw - IP packets filter.
+ipaccounting,ipacct - IP packets/traffic accounting.
+
+.Sh SYNOPSIS
+#include <netinet/ip_fw.h>
+
+setsockopt(raw_socket,IPPROTO_IP,<ipfw/ipacct option>,
+ <struct ip|struct ipfw>,<size>)
+
+Ipfw options:
+ IP_FW_ADD_BLK - add entry to blocking chain.
+ IP_FW_ADD_FWD - add entry to forwarding chain.
+ IP_FW_CHK_BLK - check ip packet against blocking chain.
+ IP_FW_CHK_FWD - check ip packet against forwarding chain.
+ IP_FW_DEL_BLK - delete entry from blocking chain.
+ IP_FW_DEL_FWD - delete entry from forwarding chain.
+ IP_FW_FLUSH - flush all blocking & forwarding chain entries.
+ IP_FW_POLICY - define default ipfw policy.
+
+Ipacct options:
+ IP_ACCT_ADD - add entry to accounting chain.
+ IP_ACCT_DEL - delete entry from accounting chain.
+ IP_ACCT_FLUSH - flush all accounting chain entries.
+ IP_ACCT_ZERO - zero all accounting chain entries.
+
+Ipfw/ipacct entry structure:
+ #define IP_FW_MAX_PORTS 10
+
+struct ip_fw {
+ struct ip_fw *next;
+ struct in_addr src, dst;
+ struct in_addr src_mask, dst_mask;
+ u_short flags;
+ u_short n_src_p, n_dst_p;
+ u_short ports[IP_FW_MAX_PORTS];
+ u_long p_cnt,b_cnt;
+}
+
+Flags values for "flags" field:
+ IP_FW_F_ALL - The entry should match all IP packets.
+ IP_FW_F_TCP - The entry should match TCP packets.
+ IP_FW_F_UDP - The entry should match UDP packets.
+ IP_FW_F_ICMP - The entry should match ICMP packets.
+ IP_FW_F_KIND - Mask value to separate protocol kind.
+ IP_FW_F_ACCEPT - This entry is accepting ( see below )
+ IP_FW_F_SRNG - Source ports are range ( see below )
+ IP_FW_F_DRNG - Destination ports are range ( see below )
+ IP_FW_F_PRN - Print this entry ( see below )
+ IP_FW_F_BIDIR - This acct entry is bidirectional ( see below )
+ IP_FW_F_MASK - Mask to match all valid flag bits.
+
+Kernel symbols to kvm_nlist():
+ struct ip_fw *ip_fw_blk_chain - chain of forwarding entries.
+ struct ip_fw *ip_fw_fwd_chain - chain of blocking entries.
+ int ip_fw_policy - default policy.
+ struct ip_fw *ip_acct_chain - chain of accounting entries.
+
+Options in the kernel configuration file:
+ IPFIREWALL - enable ipfirewall.
+ IPFIREWALL_VERBOSE - enable firewall output ( see below )
+ DEBUG_IPFIREWALL - enable extensive debugging output.
+ IPACCT - enable ipaccounting.
+
+.Sh DESCRIPTION
+Ipfirewall (later ipfw) is a system facility,which allows filtering
+of incoming and/or forwarding packets on the protocol+source/destination
+adress/ports base.
+Ipaccounting (later ipacct) is a system facility,which allows counting
+of incoming,outgoing and forwarding traffic by packet/byte count.
+
+Basic idea is that every packet checked against number of entries
+in several chains.There are 3 chains:
+ Blocking - this chain defines whenever packet should be accepted
+ ever for local delivery or for forwarding.
+ Forwarding - this chain defines whenever packet should be accepted
+ for forwarding only.
+ Accounting - this chain defines types of packets , which should be
+ counted.
+
+Entries added to chains by means of setsockopt() call on RAW IP socket.
+Options to add/remove specific entries or to flush all entries described
+above. Value passed to setsockopt() is a value of struct ip_fw for
+entry. If entry added , it checked by such rules that when we start
+searching chain for matching entry the first matching is the best match,
+[ or at least one of them :^) ].
+ That means:
+ * First in chain entries with specific protocol and small ranges
+ of src/dst adresses and ports.
+ * Later going entries with wider ranges of ports and adresses.
+ * Later entries matching every port for some adress range.
+ * Later universal entries matching any protocol.
+
+While deleting entry , every entry which equal to that passed to
+setsockopt() will be removed.
+Flush removes all entries.
+
+Every entry have several fields,by which packets matched:
+ struct ip_fw *next - next entry in chain.(Set internally)
+
+ struct in_addr src - source adress to be matched.
+ struct in_addr src_mask - source adress mask.
+ To match whole networks/subnets or adress groups
+ mask bits should be zeroed here and also
+ in src_mask field. Valuable bits should be set
+ in src_mask field.
+ struct in_addr dst - destination adress to be matched.
+ struct in_addr dst_mask - destination adress mask.
+
+ u_short flags - flags field.See exact description of flags meaning
+ in description later.
+
+ u_short n_src_p - number of source ports in "ports" array.
+ u_short n_dst_p - number of destination ports in "ports" array.
+ u_short ports[] - ports array.Overall length currently defined
+ to reasonable maximum - 10,and could be changed.
+ The packet's src port can ever match one of
+ ports[0] ... ports[--n_src_p] numbers,or if
+ flag IP_FW_F_SRNG set take port[0] as bottom
+ range value and ports[1] as top one.n_src_p should
+ be set to 2 then.If n_src_p equal to 0 , every port
+ match. The same rules apply to packet's dst port,
+ except that it matched against ports[n_src_p] ...
+ ... ports[n_src_p+n_dst_p--],or if IP_FW_F_DRNG set,
+ range is ports[n_src_p] to ports[n_srcp++].
+
+ u_long p_cnt - packets count for ipacct entries.
+ u_long b_cnt - bytes count for ipacct entries.
+
+Packet matching proceeds in following way:
+
+a) If packet entry protocol set to ALL, see c).
+
+b) If entry protocol set to TCP/UDP/ICMP and packet protocol
+ different - no match,if packet protocol and entry protocol
+ same - continue.
+
+c) If source addres pattern does not equal to packets sources adress
+ masked with src_mask , or destination pattern not equal to packets
+ destination adress masked with dst_mask - no match.
+ If they does and protocol set to ALL/ICMP - got match.
+ If they does and protocol set to TCP/UDP - continue.
+
+d) If src port doesn't match or dst port doesn't match - all
+ packet don't match. If they does - got match.
+
+In ipfw packet matched consequently against every chain entry.
+Search continues untill first matching entry found.If IP_FW_F_ACCEPT
+flag set - packet accepted.If it is not set - packet denied.
+If no matching entry found , all unmatched packets ever accepted or
+denied depending on global polici value. It can be set with
+IP_FW_POLICY raw socket option. Deny value is 0, other values
+(default 1) is accept.
+
+Entries can be added with IP_FW_F_PRN flag set.If kernel compiled
+with IPFIREWALL_VERBOSE option,packets matching this entries will
+be printed by kernel printf's.
+
+If some chain is empty,every packet accepted by this chain no
+matter what default policy is.
+
+To check whenever or not packet denied by some chain , checking
+options to setsockopt() can be issued. Then the argument is
+a buffer representing ip packet,thus it has to be
+struct ip + struct tcphdr .
+Then setsockopt() return value 0 on accept or another on deny.
+
+Ipaccounting entries added the same way as ipfw ones.Packet checked
+against all entries in chain and values of p_cnt and b_cnt in matching
+entries rised.p_cnt rises by 1 and b_cnt by ip_len value of ip packet.
+Thus all traffic size counted including IP headers.
+
+If IP_FW_F_BIDIR flag is set in accounting entry,packets counted are
+those which match entry in standart way along with packets which match
+entry while their source and destination addr/port pairs swapped.
+
+Zero option allows all accounting to be cleared.
+
+.Sh DIAGNOSTICS
+
+[EINVAL] The IP option field was improperly formed; an option
+ field was shorter than the minimum value or longer than
+ the option buffer provided.An structural error in
+ ip_fw structure occured (n_src_p+n_dst_p too big,
+ ports set for ALL/ICMP protocols etc.)
+
+.Sh SEE ALSO
+
+ip(4), setsockopt(2), kvm_nlist(3), kvm_read(3)
+
+.Sh BUGS
+ Ipfw/ipacct facilities are new and , although serious bugs has
+been tracked,some less important ones expected.
+ This man page also uncomplete bad styled.
+
+.Sh HISTORY
+ Ipfw facility has been intitially written as package to BSDI
+by Daniel Boulet <danny@BouletFermat.ab.ca>.
+ It has been havily modified and ported to FreeBSD 2.0
+by Ugen J.S.Antsilevich <ugen@NetVision.net.il>
+ Ipacct facility written for FreeBSD 2.0
+by Ugen J.S.Antsilevich <ugen@NetVision.net.il>
diff --git a/sbin/ipfw/ipfw.8 b/sbin/ipfw/ipfw.8
new file mode 100644
index 0000000..2c49119
--- /dev/null
+++ b/sbin/ipfw/ipfw.8
@@ -0,0 +1,128 @@
+.Dd November 16, 1994
+.Dt IPFW 8
+.Os
+.Sh NAME
+ipfw - controlling utility for ipfw/ipacct facilities.
+
+.Sh SYNOPSIS
+
+ ipfw [-vn] <entry-action> <chain entry pattern>
+ ipfw [-vn] <check-action> <packet pattern>
+ ipfw [-vn] <chain-action> <chain[s] type>
+
+.Sh DESCRIPTION
+ In the first synopsis form, the ipfw utility allows adding/removing of
+entries of blocking/forwarding/accounting chains.
+ In the second synopsis form, the ipfw utility checks whenever a given
+IP packet type is accepted or denied by a blocking/forwarding firewall.
+ In the third synopsis form, the ipfw utility allows global actions
+on chain-zeroing of counters, and flushing or listing of chain entries
+and their counter values.
+
+The following options are available:
+
+-v be verbose. The meaning of this option varies depending on ipfw
+ usage.
+
+-n do not resolve anything. When setting entries, do not try to resolve
+ a given address. When listing, display addresses in numeric form.
+
+These are <entry-actions>:
+
+ addb[locking] - add entry to blocking firewall.
+ delb[locking] - remove entry from blocking firewall.
+ addf[orwarding] - add entry to forwarding firewall.
+ delf[orwarding] - remove entry from forwarding firewall.
+ adda[ccounting] - add entry to accounting chain.
+ dela[ccounting] - remove entry from accounting chain.
+
+These are <check-actions>:
+ checkb[locking] - check packet against blocking firewall.
+ checkf[orwarding] - check packet against forwarding firewall.
+
+These are <chain-actions>:
+ f[lush] - remove all entries in firewall/accounting chains.
+ l[ist] - show all entries in blocking/forwarding/accounting chains.
+ z[ero] - clear chain counters(for now accounting only).
+ p[olicy] - define default firewall policy.
+
+ The <chain-entry pattern> build like this:
+ For forwarding/blocking chains:
+ d[eny] <proto/addr pattern>
+ a[ccept] <proto/addr pattern>
+ For accounting chain:
+ s[ingle] <proto/addr pattern>
+ b[idirectional] <proto/addr pattern>
+
+ The <proto/addr pattern> is:
+ all|icmp from <src addr/mask> to <dst addr/mask>
+ tcp|udp from <src addr/mask> [ports] to <dst addr/mask> [ports]
+
+ <src addr/mask>:
+ <INET IP addr | domain name> [/mask bits | :mask pattern]
+ [ports]:
+ [ port,port....|port:port] where name of service can be
+ used instead of port numeric value.
+
+When entry added to chain and -v option used,entry added with
+PRN flag set.
+
+The <packet pattern> build exactly like <chain-entry pattern>.
+
+ To l[ist] command may be passed:
+f[orwarding]|b[locking]|a[ccounting] to list specific chain or none
+to list all of them.Option -v causes output format to change so that
+packet/bytes counters printed.Standart output format fully suitable
+to be used as <chain-entry pattern>.
+
+ To f[lush] command may be passed:
+f[irewall]|a[ccounting] to remove all entries from forwarding/blocking
+chains or from accounting chain.No arguments removes all chain entries.
+
+ To z[ero] command no arguments needed,and all counters of accounting
+chain zeroed.
+
+ To p[olicy] command accepts a[ccept]|d[eny] to define default policy
+as denial/accepting.Withno arguments current default policy displayed.
+
+.Sh EXAMPLES
+
+ This command add entry which denies all tcp packets from
+hacker.evil.org to telnet port of wolf.tambov.su from being
+forwarded by the host:
+ ipfw addf deny tcp from hacker.evil.org to wolf.tambov.su telnet
+
+ This one disallows any connection from entire hackers network
+to my host:
+ ipfw addb deny all from 123.45.67.8/24 to my.host.org
+
+ Here is useful usage of lt] command to see accounting records:
+ ipfw -v list accounting (or in short form ipfw -v l a ).
+
+ Much more examples can be found in files:
+ /usr/share/misc/ipfw.samp.filters
+ /usr/share/misc/ipfw.samp.scripts
+
+.Sh SEE ALSO
+ipfirewall(4),ipaccounting(4),reboot(1)
+
+.Sh BUGS
+ WARNING!!WARNING!!WARNING!!WARNING!!WARNING!!WARNING!!WARNING!!
+ This programm can put your computer in rather unusable state.
+First time try using it from console and do *NOT* do anything
+you don't understand.
+ Remember that "ipfw flush" can solve all the problemms.
+Also take in your mind that "ipfw policy deny" combined with
+some wrong chain entry(possible the only entry which designed
+to deny some external packets) can close your computer from
+outer world for good.
+ Besides of misuse the only known bug is that entry added
+with -v option set should be deleted with same option,
+but there is no way to see this in list command.
+
+.Sh HISTORY
+ Initially this utility was written for BSDI by:
+ Daniel Boulet <danny@BouletFermat.ab.ca>
+ The FreeBSD version is written completely by:
+ Ugen J.S.Antsilevich <ugen@NetVision.net.il>
+ while synopsis partially compatible with old one.
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