IP_TRANSPARENT(2const) — Linux manual page

IP_TRANSPARENT(2const)                             IP_TRANSPARENT(2const)

NAME         top

       IP_TRANSPARENT - transparent proxying

LIBRARY         top

       Standard C library (libc, -lc)

SYNOPSIS         top

       #include <netinet/in.h>  /* Definition of IP* constants */
       #include <sys/socket.h>

       int setsockopt(int sockfd, IPPROTO_IP, IP_TRANSPARENT,
                      const int *enable, sizeof(int));

DESCRIPTION         top

       Setting this boolean option enables transparent proxying on this
       socket.

       This socket option allows the calling application to bind to a
       nonlocal IP address and operate both as a client and a server with
       the foreign address as the local endpoint.

       This requires that routing be set up in a way that packets going
       to the foreign address are routed through the TProxy box (i.e.,
       the system hosting the application that employs the IP_TRANSPARENT
       socket option).

       Enabling this socket option requires superuser privileges (the
       CAP_NET_ADMIN or CAP_NET_RAW capability).

       TProxy redirection with the iptables TPROXY target also requires
       that this option be set on the redirected socket.

ERRORS         top

       See IPPROTO_IP(2const).  See setsockopt(2).  See ip(7).

STANDARDS         top

       Linux.

HISTORY         top

       Linux 2.6.24.

SEE ALSO         top

       IPPROTO_IP(2const), setsockopt(2), ip(7)

COLOPHON         top

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Linux man-pages 6.18            2025-11-25         IP_TRANSPARENT(2const)

Pages that refer to this page: IPPROTO_IP(2const)

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