From: "Pali Rohár" <pali@kernel.org>
To: linux-man@vger.kernel.org,
Alejandro Colomar <alx.manpages@gmail.com>,
Michael Kerrisk <mtk.manpages@gmail.com>,
netdev@vger.kernel.org
Subject: [PATCH v3] netdevice.7: Update documentation for SIOCGIFADDR SIOCSIFADDR SIOCDIFADDR
Date: Sat, 16 Jan 2021 23:36:10 +0100 [thread overview]
Message-ID: <20210116223610.14230-1-pali@kernel.org> (raw)
In-Reply-To: <20210102140254.16714-1-pali@kernel.org>
Unlike SIOCGIFADDR and SIOCSIFADDR which are supported by many protocol
families, SIOCDIFADDR is supported by AF_INET6 and AF_APPLETALK only.
Unlike other protocols, AF_INET6 uses struct in6_ifreq.
Signed-off-by: Pali Rohár <pali@kernel.org>
---
man7/netdevice.7 | 64 +++++++++++++++++++++++++++++++++++++++++-------
1 file changed, 55 insertions(+), 9 deletions(-)
diff --git a/man7/netdevice.7 b/man7/netdevice.7
index 15930807c..bdc2d1922 100644
--- a/man7/netdevice.7
+++ b/man7/netdevice.7
@@ -56,9 +56,27 @@ struct ifreq {
.EE
.in
.PP
+.B AF_INET6
+is an exception.
+It passes an
+.I in6_ifreq
+structure:
+.PP
+.in +4n
+.EX
+struct in6_ifreq {
+ struct in6_addr ifr6_addr;
+ u32 ifr6_prefixlen;
+ int ifr6_ifindex; /* Interface index */
+};
+.EE
+.in
+.PP
Normally, the user specifies which device to affect by setting
.I ifr_name
-to the name of the interface.
+to the name of the interface or
+.I ifr6_ifindex
+to the index of the interface.
All other members of the structure may
share memory.
.SS Ioctls
@@ -143,13 +161,33 @@ IFF_ISATAP:Interface is RFC4214 ISATAP interface.
.PP
Setting the extended (private) interface flags is a privileged operation.
.TP
-.BR SIOCGIFADDR ", " SIOCSIFADDR
-Get or set the address of the device using
-.IR ifr_addr .
-Setting the interface address is a privileged operation.
-For compatibility, only
+.BR SIOCGIFADDR ", " SIOCSIFADDR ", " SIOCDIFADDR
+Get, set, or delete the address of the device using
+.IR ifr_addr ,
+or
+.I ifr6_addr
+with
+.IR ifr6_prefixlen .
+Setting or deleting the interface address is a privileged operation.
+For compatibility,
+.B SIOCGIFADDR
+returns only
.B AF_INET
-addresses are accepted or returned.
+addresses,
+.B SIOCSIFADDR
+accepts
+.B AF_INET
+and
+.B AF_INET6
+addresses, and
+.B SIOCDIFADDR
+deletes only
+.B AF_INET6
+addresses.
+A
+.B AF_INET
+address can be deleted by setting it to zero via
+.BR SIOCSIFADDR .
.TP
.BR SIOCGIFDSTADDR ", " SIOCSIFDSTADDR
Get or set the destination address of a point-to-point device using
@@ -351,10 +389,18 @@ The names of interfaces with no addresses or that don't have the
flag set can be found via
.IR /proc/net/dev .
.PP
-Local IPv6 IP addresses can be found via
-.I /proc/net
+.B AF_INET6
+IPv6 addresses can be read from
+.I /proc/net/if_inet6
+file or via
+.BR rtnetlink (7).
+Adding a new or deleting an existing IPv6 address can be done via
+.BR SIOCSIFADDR " / " SIOCDIFADDR
or via
.BR rtnetlink (7).
+Retrieving or changing destination IPv6 addresses of a point-to-point
+interface is possible only via
+.BR rtnetlink (7).
.SH BUGS
glibc 2.1 is missing the
.I ifr_newname
--
2.20.1
next prev parent reply other threads:[~2021-01-16 22:37 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-01-02 14:02 [PATCH] netdevice.7: Update documentation for SIOCGIFADDR SIOCSIFADDR SIOCDIFADDR Pali Rohár
2021-01-02 18:04 ` Alejandro Colomar (man-pages)
2021-01-02 18:10 ` Pali Rohár
2021-01-02 18:36 ` Pali Rohár
2021-01-02 18:39 ` [PATCH v2] " Pali Rohár
2021-01-10 16:38 ` Pali Rohár
2021-01-10 19:57 ` Alejandro Colomar (man-pages)
2021-01-12 19:26 ` Pali Rohár
2021-01-16 0:41 ` Alejandro Colomar (man-pages)
2021-01-16 22:35 ` Pali Rohár
2021-01-11 8:13 ` Michael Kerrisk (man-pages)
2021-01-10 17:47 ` Dmitry V. Levin
2021-01-12 17:51 ` Pali Rohár
2021-01-16 22:36 ` Pali Rohár [this message]
2021-01-19 20:18 ` [PATCH v3] " Alejandro Colomar (man-pages)
2021-01-27 19:29 ` Pali Rohár
2021-01-28 14:05 ` Alejandro Colomar (man-pages)
2021-01-28 14:04 ` Alejandro Colomar (man-pages)
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