xref: /aosp_15_r20/external/iptables/extensions/libxt_SNAT.man (revision a71a954618bbadd4a345637e5edcf36eec826889)
1*a71a9546SAutomerger Merge WorkerThis target is only valid in the
2*a71a9546SAutomerger Merge Worker.B nat
3*a71a9546SAutomerger Merge Workertable, in the
4*a71a9546SAutomerger Merge Worker.B POSTROUTING
5*a71a9546SAutomerger Merge Workerand
6*a71a9546SAutomerger Merge Worker.B INPUT
7*a71a9546SAutomerger Merge Workerchains, and user-defined chains which are only called from those
8*a71a9546SAutomerger Merge Workerchains.  It specifies that the source address of the packet should be
9*a71a9546SAutomerger Merge Workermodified (and all future packets in this connection will also be
10*a71a9546SAutomerger Merge Workermangled), and rules should cease being examined.  It takes the
11*a71a9546SAutomerger Merge Workerfollowing options:
12*a71a9546SAutomerger Merge Worker.TP
13*a71a9546SAutomerger Merge Worker\fB\-\-to\-source\fP [\fIipaddr\fP[\fB\-\fP\fIipaddr\fP]][\fB:\fP\fIport\fP[\fB\-\fP\fIport\fP]]
14*a71a9546SAutomerger Merge Workerwhich can specify a single new source IP address, an inclusive range
15*a71a9546SAutomerger Merge Workerof IP addresses. Optionally a port range,
16*a71a9546SAutomerger Merge Workerif the rule also specifies one of the following protocols:
17*a71a9546SAutomerger Merge Worker\fBtcp\fP, \fBudp\fP, \fBdccp\fP or \fBsctp\fP.
18*a71a9546SAutomerger Merge WorkerIf no port range is specified, then source ports below 512 will be
19*a71a9546SAutomerger Merge Workermapped to other ports below 512: those between 512 and 1023 inclusive
20*a71a9546SAutomerger Merge Workerwill be mapped to ports below 1024, and other ports will be mapped to
21*a71a9546SAutomerger Merge Worker1024 or above. Where possible, no port alteration will occur.
22*a71a9546SAutomerger Merge Worker.TP
23*a71a9546SAutomerger Merge Worker\fB\-\-random\fP
24*a71a9546SAutomerger Merge WorkerRandomize source port mapping through a hash-based algorithm (kernel >= 2.6.21).
25*a71a9546SAutomerger Merge Worker.TP
26*a71a9546SAutomerger Merge Worker\fB\-\-random-fully\fP
27*a71a9546SAutomerger Merge WorkerFully randomize source port mapping through a PRNG (kernel >= 3.14).
28*a71a9546SAutomerger Merge Worker.TP
29*a71a9546SAutomerger Merge Worker\fB\-\-persistent\fP
30*a71a9546SAutomerger Merge WorkerGives a client the same source-/destination-address for each connection.
31*a71a9546SAutomerger Merge WorkerThis supersedes the SAME target. Support for persistent mappings is available
32*a71a9546SAutomerger Merge Workerfrom 2.6.29-rc2.
33*a71a9546SAutomerger Merge Worker.PP
34*a71a9546SAutomerger Merge WorkerKernels prior to 2.6.36-rc1 don't have the ability to
35*a71a9546SAutomerger Merge Worker.B SNAT
36*a71a9546SAutomerger Merge Workerin the
37*a71a9546SAutomerger Merge Worker.B INPUT
38*a71a9546SAutomerger Merge Workerchain.
39*a71a9546SAutomerger Merge Worker.TP
40*a71a9546SAutomerger Merge WorkerIPv6 support available since Linux kernels >= 3.7.
41