diff options
Diffstat (limited to 'Documentation/networking')
| -rw-r--r-- | Documentation/networking/cdc_mbim.txt | 4 | ||||
| -rw-r--r-- | Documentation/networking/dsa/dsa.txt | 24 | ||||
| -rw-r--r-- | Documentation/networking/gtp.txt | 135 | ||||
| -rw-r--r-- | Documentation/networking/ip-sysctl.txt | 47 | ||||
| -rw-r--r-- | Documentation/networking/kcm.txt | 2 | ||||
| -rw-r--r-- | Documentation/networking/netfilter-sysctl.txt | 10 | ||||
| -rw-r--r-- | Documentation/networking/packet_mmap.txt | 9 | ||||
| -rw-r--r-- | Documentation/networking/regulatory.txt | 8 | ||||
| -rw-r--r-- | Documentation/networking/vrf.txt | 7 |
9 files changed, 184 insertions, 62 deletions
diff --git a/Documentation/networking/cdc_mbim.txt b/Documentation/networking/cdc_mbim.txt index a15ea602aa52..b9482ca10254 100644 --- a/Documentation/networking/cdc_mbim.txt +++ b/Documentation/networking/cdc_mbim.txt @@ -38,7 +38,7 @@ Basic usage =========== MBIM functions are inactive when unmanaged. The cdc_mbim driver only -provides an userspace interface to the MBIM control channel, and will +provides a userspace interface to the MBIM control channel, and will not participate in the management of the function. This implies that a userspace MBIM management application always is required to enable a MBIM function. @@ -200,7 +200,7 @@ structure described in section 10.5.29 of [1]. The DSS VLAN subdevices are used as a practical interface between the shared MBIM data channel and a MBIM DSS aware userspace application. It is not intended to be presented as-is to an end user. The -assumption is that an userspace application initiating a DSS session +assumption is that a userspace application initiating a DSS session also takes care of the necessary framing of the DSS data, presenting the stream to the end user in an appropriate way for the stream type. diff --git a/Documentation/networking/dsa/dsa.txt b/Documentation/networking/dsa/dsa.txt index 63912ef34606..b8b40753133e 100644 --- a/Documentation/networking/dsa/dsa.txt +++ b/Documentation/networking/dsa/dsa.txt @@ -295,7 +295,6 @@ DSA currently leverages the following subsystems: - MDIO/PHY library: drivers/net/phy/phy.c, mdio_bus.c - Switchdev: net/switchdev/* - Device Tree for various of_* functions -- HWMON: drivers/hwmon/* MDIO/PHY library ---------------- @@ -349,12 +348,6 @@ Documentation/devicetree/bindings/net/dsa/dsa.txt. PHY/MDIO library helper functions such as of_get_phy_mode(), of_phy_connect() are also used to query per-port PHY specific details: interface connection, MDIO bus location etc.. -HWMON ------ - -Some switch drivers feature internal temperature sensors which are exposed as -regular HWMON devices in /sys/class/hwmon/. - Driver development ================== @@ -495,23 +488,6 @@ Power management BR_STATE_DISABLED and propagating changes to the hardware if this port is disabled while being a bridge member -Hardware monitoring -------------------- - -These callbacks are only available if CONFIG_NET_DSA_HWMON is enabled: - -- get_temp: this function queries the given switch for its temperature - -- get_temp_limit: this function returns the switch current maximum temperature - limit - -- set_temp_limit: this function configures the maximum temperature limit allowed - -- get_temp_alarm: this function returns the critical temperature threshold - returning an alarm notification - -See Documentation/hwmon/sysfs-interface for details. - Bridge layer ------------ diff --git a/Documentation/networking/gtp.txt b/Documentation/networking/gtp.txt new file mode 100644 index 000000000000..93e96750f103 --- /dev/null +++ b/Documentation/networking/gtp.txt @@ -0,0 +1,135 @@ +The Linux kernel GTP tunneling module +====================================================================== +Documentation by Harald Welte <laforge@gnumonks.org> + +In 'drivers/net/gtp.c' you are finding a kernel-level implementation +of a GTP tunnel endpoint. + +== What is GTP == + +GTP is the Generic Tunnel Protocol, which is a 3GPP protocol used for +tunneling User-IP payload between a mobile station (phone, modem) +and the interconnection between an external packet data network (such +as the internet). + +So when you start a 'data connection' from your mobile phone, the +phone will use the control plane to signal for the establishment of +such a tunnel between that external data network and the phone. The +tunnel endpoints thus reside on the phone and in the gateway. All +intermediate nodes just transport the encapsulated packet. + +The phone itself does not implement GTP but uses some other +technology-dependent protocol stack for transmitting the user IP +payload, such as LLC/SNDCP/RLC/MAC. + +At some network element inside the cellular operator infrastructure +(SGSN in case of GPRS/EGPRS or classic UMTS, hNodeB in case of a 3G +femtocell, eNodeB in case of 4G/LTE), the cellular protocol stacking +is translated into GTP *without breaking the end-to-end tunnel*. So +intermediate nodes just perform some specific relay function. + +At some point the GTP packet ends up on the so-called GGSN (GSM/UMTS) +or P-GW (LTE), which terminates the tunnel, decapsulates the packet +and forwards it onto an external packet data network. This can be +public internet, but can also be any private IP network (or even +theoretically some non-IP network like X.25). + +You can find the protocol specification in 3GPP TS 29.060, available +publicly via the 3GPP website at http://www.3gpp.org/DynaReport/29060.htm + +A direct PDF link to v13.6.0 is provided for convenience below: +http://www.etsi.org/deliver/etsi_ts/129000_129099/129060/13.06.00_60/ts_129060v130600p.pdf + +== The Linux GTP tunnelling module == + +The module implements the function of a tunnel endpoint, i.e. it is +able to decapsulate tunneled IP packets in the uplink originated by +the phone, and encapsulate raw IP packets received from the external +packet network in downlink towards the phone. + +It *only* implements the so-called 'user plane', carrying the User-IP +payload, called GTP-U. It does not implement the 'control plane', +which is a signaling protocol used for establishment and teardown of +GTP tunnels (GTP-C). + +So in order to have a working GGSN/P-GW setup, you will need a +userspace program that implements the GTP-C protocol and which then +uses the netlink interface provided by the GTP-U module in the kernel +to configure the kernel module. + +This split architecture follows the tunneling modules of other +protocols, e.g. PPPoE or L2TP, where you also run a userspace daemon +to handle the tunnel establishment, authentication etc. and only the +data plane is accelerated inside the kernel. + +Don't be confused by terminology: The GTP User Plane goes through +kernel accelerated path, while the GTP Control Plane goes to +Userspace :) + +The official homepge of the module is at +https://osmocom.org/projects/linux-kernel-gtp-u/wiki + +== Userspace Programs with Linux Kernel GTP-U support == + +At the time of this writing, there are at least two Free Software +implementations that implement GTP-C and can use the netlink interface +to make use of the Linux kernel GTP-U support: + +* OpenGGSN (classic 2G/3G GGSN in C): + https://osmocom.org/projects/openggsn/wiki/OpenGGSN + +* ergw (GGSN + P-GW in Erlang): + https://github.com/travelping/ergw + +== Userspace Library / Command Line Utilities == + +There is a userspace library called 'libgtpnl' which is based on +libmnl and which implements a C-language API towards the netlink +interface provided by the Kernel GTP module: + +http://git.osmocom.org/libgtpnl/ + +== Protocol Versions == + +There are two different versions of GTP-U: v0 and v1. Both are +implemented in the Kernel GTP module. Version 0 is a legacy version, +and deprecated from recent 3GPP specifications. + +There are three versions of GTP-C: v0, v1, and v2. As the kernel +doesn't implement GTP-C, we don't have to worry about this. It's the +responsibility of the control plane implementation in userspace to +implement that. + +== IPv6 == + +The 3GPP specifications indicate either IPv4 or IPv6 can be used both +on the inner (user) IP layer, or on the outer (transport) layer. + +Unfortunately, the Kernel module currently supports IPv6 neither for +the User IP payload, nor for the outer IP layer. Patches or other +Contributions to fix this are most welcome! + +== Mailing List == + +If yo have questions regarding how to use the Kernel GTP module from +your own software, or want to contribute to the code, please use the +osmocom-net-grps mailing list for related discussion. The list can be +reached at osmocom-net-gprs@lists.osmocom.org and the mailman +interface for managign your subscription is at +https://lists.osmocom.org/mailman/listinfo/osmocom-net-gprs + +== Issue Tracker == + +The Osmocom project maintains an issue tracker for the Kernel GTP-U +module at +https://osmocom.org/projects/linux-kernel-gtp-u/issues + +== History / Acknowledgements == + +The Module was originally created in 2012 by Harald Welte, but never +completed. Pablo came in to finish the mess Harald left behind. But +doe to a lack of user interest, it never got merged. + +In 2015, Andreas Schultz came to the rescue and fixed lots more bugs, +extended it with new features and finally pushed all of us to get it +mainline, where it was merged in 4.7.0. diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt index 7dd65c9cf707..fc73eeb7b3b8 100644 --- a/Documentation/networking/ip-sysctl.txt +++ b/Documentation/networking/ip-sysctl.txt @@ -246,21 +246,12 @@ tcp_dsack - BOOLEAN Allows TCP to send "duplicate" SACKs. tcp_early_retrans - INTEGER - Enable Early Retransmit (ER), per RFC 5827. ER lowers the threshold - for triggering fast retransmit when the amount of outstanding data is - small and when no previously unsent data can be transmitted (such - that limited transmit could be used). Also controls the use of - Tail loss probe (TLP) that converts RTOs occurring due to tail - losses into fast recovery (draft-dukkipati-tcpm-tcp-loss-probe-01). + Tail loss probe (TLP) converts RTOs occurring due to tail + losses into fast recovery (draft-ietf-tcpm-rack). Note that + TLP requires RACK to function properly (see tcp_recovery below) Possible values: - 0 disables ER - 1 enables ER - 2 enables ER but delays fast recovery and fast retransmit - by a fourth of RTT. This mitigates connection falsely - recovers when network has a small degree of reordering - (less than 3 packets). - 3 enables delayed ER and TLP. - 4 enables TLP only. + 0 disables TLP + 3 or 4 enables TLP Default: 3 tcp_ecn - INTEGER @@ -712,18 +703,6 @@ tcp_thin_linear_timeouts - BOOLEAN Documentation/networking/tcp-thin.txt Default: 0 -tcp_thin_dupack - BOOLEAN - Enable dynamic triggering of retransmissions after one dupACK - for thin streams. If set, a check is performed upon reception - of a dupACK to determine if the stream is thin (less than 4 - packets in flight). As long as the stream is found to be thin, - data is retransmitted on the first received dupACK. This - improves retransmission latency for non-aggressive thin - streams, often found to be time-dependent. - For more information on thin streams, see - Documentation/networking/tcp-thin.txt - Default: 0 - tcp_limit_output_bytes - INTEGER Controls TCP Small Queue limit per tcp socket. TCP bulk sender tends to increase packets in flight until it @@ -742,6 +721,13 @@ tcp_challenge_ack_limit - INTEGER UDP variables: +udp_l3mdev_accept - BOOLEAN + Enabling this option allows a "global" bound socket to work + across L3 master domains (e.g., VRFs) with packets capable of + being received regardless of the L3 domain in which they + originated. Only valid when the kernel was compiled with + CONFIG_NET_L3_MASTER_DEV. + udp_mem - vector of 3 INTEGERs: min, pressure, max Number of pages allowed for queueing by all UDP sockets. @@ -843,6 +829,15 @@ ip_local_reserved_ports - list of comma separated ranges Default: Empty +ip_unprivileged_port_start - INTEGER + This is a per-namespace sysctl. It defines the first + unprivileged port in the network namespace. Privileged ports + require root or CAP_NET_BIND_SERVICE in order to bind to them. + To disable all privileged ports, set this to 0. It may not + overlap with the ip_local_reserved_ports range. + + Default: 1024 + ip_nonlocal_bind - BOOLEAN If set, allows processes to bind() to non-local IP addresses, which can be quite useful - but may break some applications. diff --git a/Documentation/networking/kcm.txt b/Documentation/networking/kcm.txt index 3476ede5bc2c..9a513295b07c 100644 --- a/Documentation/networking/kcm.txt +++ b/Documentation/networking/kcm.txt @@ -272,7 +272,7 @@ on the socket thus waking up the application thread. When the application sees the error (which may just be a disconnect) it should unattach the socket from KCM and then close it. It is assumed that once an error is posted on the TCP socket the data stream is unrecoverable (i.e. an error -may have occurred in in the middle of receiving a messssge). +may have occurred in the middle of receiving a messssge). TCP connection monitoring ------------------------- diff --git a/Documentation/networking/netfilter-sysctl.txt b/Documentation/networking/netfilter-sysctl.txt new file mode 100644 index 000000000000..55791e50e169 --- /dev/null +++ b/Documentation/networking/netfilter-sysctl.txt @@ -0,0 +1,10 @@ +/proc/sys/net/netfilter/* Variables: + +nf_log_all_netns - BOOLEAN + 0 - disabled (default) + not 0 - enabled + + By default, only init_net namespace can log packets into kernel log + with LOG target; this aims to prevent containers from flooding host + kernel log. If enabled, this target also works in other network + namespaces. This variable is only accessible from init_net. diff --git a/Documentation/networking/packet_mmap.txt b/Documentation/networking/packet_mmap.txt index daa015af16a0..f3b9e507ab05 100644 --- a/Documentation/networking/packet_mmap.txt +++ b/Documentation/networking/packet_mmap.txt @@ -565,7 +565,7 @@ TPACKET_V1 --> TPACKET_V2: (void *)hdr + TPACKET_ALIGN(sizeof(struct tpacket_hdr)) TPACKET_V2 --> TPACKET_V3: - - Flexible buffer implementation: + - Flexible buffer implementation for RX_RING: 1. Blocks can be configured with non-static frame-size 2. Read/poll is at a block-level (as opposed to packet-level) 3. Added poll timeout to avoid indefinite user-space wait @@ -574,7 +574,12 @@ TPACKET_V2 --> TPACKET_V3: 4.1 block::timeout 4.2 tpkt_hdr::sk_rxhash - RX Hash data available in user space - - Currently only RX_RING available + - TX_RING semantics are conceptually similar to TPACKET_V2; + use tpacket3_hdr instead of tpacket2_hdr, and TPACKET3_HDRLEN + instead of TPACKET2_HDRLEN. In the current implementation, + the tp_next_offset field in the tpacket3_hdr MUST be set to + zero, indicating that the ring does not hold variable sized frames. + Packets with non-zero values of tp_next_offset will be dropped. ------------------------------------------------------------------------------- + AF_PACKET fanout mode diff --git a/Documentation/networking/regulatory.txt b/Documentation/networking/regulatory.txt index 356f791af574..7818b5fe448b 100644 --- a/Documentation/networking/regulatory.txt +++ b/Documentation/networking/regulatory.txt @@ -156,12 +156,12 @@ struct ieee80211_regdomain mydriver_jp_regdom = { //.alpha2 = "99", /* If I have no alpha2 to map it to */ .reg_rules = { /* IEEE 802.11b/g, channels 1..14 */ - REG_RULE(2412-20, 2484+20, 40, 6, 20, 0), + REG_RULE(2412-10, 2484+10, 40, 6, 20, 0), /* IEEE 802.11a, channels 34..48 */ - REG_RULE(5170-20, 5240+20, 40, 6, 20, + REG_RULE(5170-10, 5240+10, 40, 6, 20, NL80211_RRF_NO_IR), /* IEEE 802.11a, channels 52..64 */ - REG_RULE(5260-20, 5320+20, 40, 6, 20, + REG_RULE(5260-10, 5320+10, 40, 6, 20, NL80211_RRF_NO_IR| NL80211_RRF_DFS), } @@ -205,7 +205,7 @@ the data in regdb.c as an alternative to using CRDA. The file net/wireless/db.txt should be kept up-to-date with the db.txt file available in the git repository here: - git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-regdb.git + git://git.kernel.org/pub/scm/linux/kernel/git/sforshee/wireless-regdb.git Again, most users in most situations should be using the CRDA package provided with their distribution, and in most other situations users diff --git a/Documentation/networking/vrf.txt b/Documentation/networking/vrf.txt index 755dab856392..3918dae964d4 100644 --- a/Documentation/networking/vrf.txt +++ b/Documentation/networking/vrf.txt @@ -98,10 +98,11 @@ VRF device: or to specify the output device using cmsg and IP_PKTINFO. -TCP services running in the default VRF context (ie., not bound to any VRF -device) can work across all VRF domains by enabling the tcp_l3mdev_accept -sysctl option: +TCP & UDP services running in the default VRF context (ie., not bound +to any VRF device) can work across all VRF domains by enabling the +tcp_l3mdev_accept and udp_l3mdev_accept sysctl options: sysctl -w net.ipv4.tcp_l3mdev_accept=1 + sysctl -w net.ipv4.udp_l3mdev_accept=1 netfilter rules on the VRF device can be used to limit access to services running in the default VRF context as well. |
