linux/net/sctp
Jason Gunthorpe 299ee123e1 sctp: Fixup v4mapped behaviour to comply with Sock API
The SCTP socket extensions API document describes the v4mapping option as
follows:

8.1.15.  Set/Clear IPv4 Mapped Addresses (SCTP_I_WANT_MAPPED_V4_ADDR)

   This socket option is a Boolean flag which turns on or off the
   mapping of IPv4 addresses.  If this option is turned on, then IPv4
   addresses will be mapped to V6 representation.  If this option is
   turned off, then no mapping will be done of V4 addresses and a user
   will receive both PF_INET6 and PF_INET type addresses on the socket.
   See [RFC3542] for more details on mapped V6 addresses.

This description isn't really in line with what the code does though.

Introduce addr_to_user (renamed addr_v4map), which should be called
before any sockaddr is passed back to user space. The new function
places the sockaddr into the correct format depending on the
SCTP_I_WANT_MAPPED_V4_ADDR option.

Audit all places that touched v4mapped and either sanely construct
a v4 or v6 address then call addr_to_user, or drop the
unnecessary v4mapped check entirely.

Audit all places that call addr_to_user and verify they are on a sycall
return path.

Add a custom getname that formats the address properly.

Several bugs are addressed:
 - SCTP_I_WANT_MAPPED_V4_ADDR=0 often returned garbage for
   addresses to user space
 - The addr_len returned from recvmsg was not correct when
   returning AF_INET on a v6 socket
 - flowlabel and scope_id were not zerod when promoting
   a v4 to v6
 - Some syscalls like bind and connect behaved differently
   depending on v4mapped

Tested bind, getpeername, getsockname, connect, and recvmsg for proper
behaviour in v4mapped = 1 and 0 cases.

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Tested-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-07-31 21:49:06 -07:00
..
associola.c net: sctp: inherit auth_capable on INIT collisions 2014-07-22 19:56:58 -07:00
auth.c net: sctp: cache auth_enable per endpoint 2014-04-18 18:32:00 -04:00
bind_addr.c sctp: Fix FSF address in file headers 2013-12-06 12:37:56 -05:00
chunk.c sctp: fix checkpatch errors with space required or prohibited 2013-12-26 13:47:47 -05:00
debug.c sctp: Fix FSF address in file headers 2013-12-06 12:37:56 -05:00
endpointola.c net: sctp: migrate most recently used transport to ktime 2014-06-11 12:23:17 -07:00
input.c sctp: remove macros sctp_bh_[un]lock_sock 2014-01-21 18:41:36 -08:00
inqueue.c sctp: Fix FSF address in file headers 2013-12-06 12:37:56 -05:00
ipv6.c sctp: Fixup v4mapped behaviour to comply with Sock API 2014-07-31 21:49:06 -07:00
Kconfig net: sctp: get rid of SCTP_DBG_TSNS entirely 2013-07-02 00:08:03 -07:00
Makefile net: sctp: Inline the functions from command.c 2014-07-08 14:38:48 -07:00
objcnt.c sctp: fix checkpatch errors with (foo*)|foo * bar|foo* bar 2013-12-26 13:47:47 -05:00
output.c net: sctp: Rename SCTP_XMIT_NAGLE_DELAY to SCTP_XMIT_DELAY 2014-07-22 13:32:11 -07:00
outqueue.c net: sctp: Rename SCTP_XMIT_NAGLE_DELAY to SCTP_XMIT_DELAY 2014-07-22 13:32:11 -07:00
primitive.c sctp: Fix FSF address in file headers 2013-12-06 12:37:56 -05:00
probe.c sctp: loading sctp when load sctp_probe 2013-12-16 20:04:27 -05:00
proc.c snmp: fix some left over of snmp stats 2014-05-14 15:33:47 -04:00
protocol.c sctp: Fixup v4mapped behaviour to comply with Sock API 2014-07-31 21:49:06 -07:00
sm_make_chunk.c ktime: add ktime_after and ktime_before helper 2014-06-11 12:23:17 -07:00
sm_sideeffect.c net: sctp: Don't transition to PF state when transport has exhausted 'Path.Max.Retrans'. 2014-04-27 23:41:14 -04:00
sm_statefuns.c net: sctp: remove unnecessary break after return/goto 2014-07-15 16:27:01 -07:00
sm_statetable.c sctp: fix checkpatch errors with indent 2013-12-26 13:47:48 -05:00
socket.c sctp: Fixup v4mapped behaviour to comply with Sock API 2014-07-31 21:49:06 -07:00
ssnmap.c sctp: Fix FSF address in file headers 2013-12-06 12:37:56 -05:00
sysctl.c net: sctp: only warn in proc_sctp_do_alpha_beta if write 2014-07-02 18:44:07 -07:00
transport.c sctp: Fixup v4mapped behaviour to comply with Sock API 2014-07-31 21:49:06 -07:00
tsnmap.c sctp: Fix FSF address in file headers 2013-12-06 12:37:56 -05:00
ulpevent.c sctp: Fixup v4mapped behaviour to comply with Sock API 2014-07-31 21:49:06 -07:00
ulpqueue.c sctp: add support for busy polling to sctp protocol 2014-04-20 18:18:55 -04:00