[LEDE-DEV] [PATCH netifd] system-linux: add VXLAN support

Felix Fietkau nbd at nbd.name
Sat Feb 25 02:51:25 PST 2017


On 2017-02-24 20:52, Hans Dedecker wrote:
> On Fri, Feb 24, 2017 at 6:12 PM, Matthias Schiffer
> <mschiffer at universe-factory.net> wrote:
>> On 02/24/2017 05:53 PM, Hans Dedecker wrote:
>>> On Thursday, 23 February 2017 22:23:32 CET Matthias Schiffer wrote:
>>>> VXLAN shares many attributes with the tunnel devices, so it is implemented
>>>> as a new tunnel type. The 'remote' attribute can be used for an unicast
>>>> peer or a multicast group.
>>>>
>>>> The IANA-assigned port 4789 is used by default, instead of the non-standard
>>>> port Linux defaults to.
>>>>
>>>> Signed-off-by: Matthias Schiffer <mschiffer at universe-factory.net>
>>>> ---
>>>>
>>>> I've also added a matching proto package in my staging tree. Seems to work
>>>> fine and I could probably just push this myself, but I prefer to get a
>>>> least a little review as I'm not really familar with the netifd code.
>>>>
>>>>
>>>>  system-linux.c | 153
>>>> ++++++++++++++++++++++++++++++++++++++++++++++++++++++++- system.c       |
>>>>  3 ++
>>>>  system.h       |   3 ++
>>>>  3 files changed, 158 insertions(+), 1 deletion(-)
>>>>
>>>> diff --git a/system-linux.c b/system-linux.c
>>>> index f4d6c25..fa698cf 100644
>>>> --- a/system-linux.c
>>>> +++ b/system-linux.c
>>>> @@ -4,6 +4,7 @@
>>>>   * Copyright (C) 2013 Jo-Philipp Wich <jow at openwrt.org>
>>>>   * Copyright (C) 2013 Steven Barth <steven at midlink.org>
>>>>   * Copyright (C) 2014 Gioacchino Mazzurco <gio at eigenlab.org>
>>>> + * Copyright (C) 2017 Matthias Schiffer <mschiffer at universe-factory.net>
>>>>   *
>>>>   * This program is free software; you can redistribute it and/or modify
>>>>   * it under the terms of the GNU General Public License version 2
>>>> @@ -25,6 +26,7 @@
>>>>  #include <net/if_arp.h>
>>>>
>>>>  #include <arpa/inet.h>
>>>> +#include <netinet/ether.h>
>>>>  #include <netinet/in.h>
>>>>
>>>>  #include <linux/rtnetlink.h>
>>>> @@ -2540,6 +2542,148 @@ failure:
>>>>  }
>>>>  #endif
>>>>
>>>> +#ifdef IFLA_VXLAN_MAX
>>>> +static int system_add_vxlan(const char *name, const unsigned int link,
>>>> struct blob_attr **tb, bool v6) +{
>>>> +    struct nl_msg *msg;
>>>> +    struct nlattr *linkinfo, *data;
>>>> +    struct ifinfomsg iim = { .ifi_family = AF_UNSPEC, };
>>>> +    struct blob_attr *cur;
>>>> +    int ret = 0;
>>>> +
>>>> +    msg = nlmsg_alloc_simple(RTM_NEWLINK, NLM_F_REQUEST | NLM_F_CREATE |
>>>> NLM_F_EXCL); +
>>>> +    if (!msg)
>>>> +            return -1;
>>>> +
>>>> +    nlmsg_append(msg, &iim, sizeof(iim), 0);
>>>> +
>>>> +    nla_put_string(msg, IFLA_IFNAME, name);
>>>> +
>>>> +    if ((cur = tb[TUNNEL_ATTR_MACADDR])) {
>>>> +            struct ether_addr *ea = ether_aton(blobmsg_get_string(cur));
>>>> +            if (!ea) {
>>>> +                    ret = -EINVAL;
>>>> +                    goto failure;
>>>> +            }
>>>> +
>>>> +            nla_put(msg, IFLA_ADDRESS, ETH_ALEN, ea);
>>>> +    }
>>>> +
>>>> +    if ((cur = tb[TUNNEL_ATTR_MTU])) {
>>>> +            uint32_t mtu = blobmsg_get_u32(cur);
>>>> +            nla_put_u32(msg, IFLA_MTU, mtu);
>>>> +    }
>>>> +
>>>> +    if (!(linkinfo = nla_nest_start(msg, IFLA_LINKINFO))) {
>>>> +            ret = -ENOMEM;
>>>> +            goto failure;
>>>> +    }
>>>> +
>>>> +    nla_put_string(msg, IFLA_INFO_KIND, "vxlan");
>>>> +
>>>> +    if (!(data = nla_nest_start(msg, IFLA_INFO_DATA))) {
>>>> +            ret = -ENOMEM;
>>>> +            goto failure;
>>>> +    }
>>>> +
>>>> +    if (link)
>>>> +            nla_put_u32(msg, IFLA_VXLAN_LINK, link);
>>>> +
>>>> +    if ((cur = tb[TUNNEL_ATTR_ID])) {
>>>> +            uint32_t id = blobmsg_get_u32(cur);
>>>> +            if (id >= (1u << 24) - 1) {
>>>> +                    ret = -EINVAL;
>>>> +                    goto failure;
>>>> +            }
>>>> +
>>>> +            nla_put_u32(msg, IFLA_VXLAN_ID, id);
>>>> +    }
>>>> +
>>>> +    if (v6) {
>>>> +            struct in6_addr in6buf;
>>>> +            if ((cur = tb[TUNNEL_ATTR_LOCAL])) {
>>>> +                    if (inet_pton(AF_INET6, blobmsg_data(cur), &in6buf) < 1) {
>>>> +                            ret = -EINVAL;
>>>> +                            goto failure;
>>>> +                    }
>>>> +                    nla_put(msg, IFLA_VXLAN_LOCAL6, sizeof(in6buf), &in6buf);
>>>> +            }
>>>> +
>>>> +            if ((cur = tb[TUNNEL_ATTR_REMOTE])) {
>>>> +                    if (inet_pton(AF_INET6, blobmsg_data(cur), &in6buf) < 1) {
>>>> +                            ret = -EINVAL;
>>>> +                            goto failure;
>>>> +                    }
>>>> +                    nla_put(msg, IFLA_VXLAN_GROUP6, sizeof(in6buf), &in6buf);
>>>> +            }
>>>> +    } else {
>>>> +            struct in_addr inbuf;
>>>> +
>>>> +            if ((cur = tb[TUNNEL_ATTR_LOCAL])) {
>>>> +                    if (inet_pton(AF_INET, blobmsg_data(cur), &inbuf) < 1) {
>>>> +                            ret = -EINVAL;
>>>> +                            goto failure;
>>>> +                    }
>>>> +                    nla_put(msg, IFLA_VXLAN_LOCAL, sizeof(inbuf), &inbuf);
>>>> +            }
>>>> +
>>>> +            if ((cur = tb[TUNNEL_ATTR_REMOTE])) {
>>>> +                    if (inet_pton(AF_INET, blobmsg_data(cur), &inbuf) < 1) {
>>>> +                            ret = -EINVAL;
>>>> +                            goto failure;
>>>> +                    }
>>>> +                    nla_put(msg, IFLA_VXLAN_GROUP, sizeof(inbuf), &inbuf);
>>>> +            }
>>>> +    }
>>>> +
>>>> +    uint32_t port = 4789;
>>>> +    if ((cur = tb[TUNNEL_ATTR_PORT])) {
>>>> +            port = blobmsg_get_u32(cur);
>>>> +            if (port < 1 || port > 65535) {
>>>> +                    ret = -EINVAL;
>>>> +                    goto failure;
>>>> +            }
>>>> +    }
>>>> +    nla_put_u16(msg, IFLA_VXLAN_PORT, htons(port));
>>>> +
>>>> +    if ((cur = tb[TUNNEL_ATTR_TOS])) {
>>>> +            char *str = blobmsg_get_string(cur);
>>>> +            unsigned tos = 1;
>>>> +
>>>> +            if (strcmp(str, "inherit")) {
>>>> +                    if (!system_tos_aton(str, &tos))
>>>> +                            return -EINVAL;
>>>> +            }
>>>> +
>>>> +            nla_put_u8(msg, IFLA_VXLAN_TOS, tos);
>>>> +    }
>>>> +
>>>> +    if ((cur = tb[TUNNEL_ATTR_TTL])) {
>>>> +            uint32_t ttl = blobmsg_get_u32(cur);
>>>> +            if (ttl < 1 || ttl > 255) {
>>>> +                    ret = -EINVAL;
>>>> +                    goto failure;
>>>> +            }
>>>> +
>>>> +            nla_put_u8(msg, IFLA_VXLAN_TTL, ttl);
>>>> +    }
>>>> +
>>>> +    nla_nest_end(msg, data);
>>>> +    nla_nest_end(msg, linkinfo);
>>>> +
>>>> +    ret = system_rtnl_call(msg);
>>>> +    if (ret)
>>>> +            D(SYSTEM, "Error adding vxlan '%s': %d\n", name, ret);
>>>> +
>>>> +    return ret;
>>>> +
>>>> +failure:
>>>> +    nlmsg_free(msg);
>>>> +    return ret;
>>>> +}
>>>> +#endif
>>>> +
>>>>  static int system_add_proto_tunnel(const char *name, const uint8_t proto,
>>>> const unsigned int link, struct blob_attr **tb) {
>>>>      struct blob_attr *cur;
>>>> @@ -2609,7 +2753,8 @@ static int __system_del_ip_tunnel(const char *name,
>>>> struct blob_attr **tb)
>>>>
>>>>      if (!strcmp(str, "greip") || !strcmp(str, "gretapip") ||
>>>>          !strcmp(str, "greip6") || !strcmp(str, "gretapip6") ||
>>>> -        !strcmp(str, "vtiip") || !strcmp(str, "vtiip6"))
>>>> +        !strcmp(str, "vtiip") || !strcmp(str, "vtiip6") ||
>>>> +        !strcmp(str, "vxlan") || !strcmp(str, "vxlan6"))
>>>>              return system_link_del(name);
>>>>      else
>>>>              return tunnel_ioctl(name, SIOCDELTUNNEL, NULL);
>>>> @@ -2833,6 +2978,12 @@ failure:
>>>>      } else if (!strcmp(str, "vtiip6")) {
>>>>              return system_add_vti_tunnel(name, "vti6", link, tb, true);
>>>>  #endif
>>>> +#ifdef IFLA_VXLAN_MAX
>>>> +    } else if(!strcmp(str, "vxlan")) {
>>>> +            return system_add_vxlan(name, link, tb, false);
>>>> +    } else if(!strcmp(str, "vxlan6")) {
>>>> +            return system_add_vxlan(name, link, tb, true);
>>>> +#endif
>>>>  #endif
>>>>      } else if (!strcmp(str, "ipip")) {
>>>>              return system_add_proto_tunnel(name, IPPROTO_IPIP, link, tb);
>>>> diff --git a/system.c b/system.c
>>>> index e57084f..981d16c 100644
>>>> --- a/system.c
>>>> +++ b/system.c
>>>> @@ -28,6 +28,9 @@ static const struct blobmsg_policy
>>>> tunnel_attrs[__TUNNEL_ATTR_MAX] = { [TUNNEL_ATTR_LINK] = { .name = "link",
>>>> .type = BLOBMSG_TYPE_STRING }, [TUNNEL_ATTR_FMRS] = { .name = "fmrs", .type
>>>> = BLOBMSG_TYPE_ARRAY }, [TUNNEL_ATTR_INFO] = { .name = "info", .type =
>>>> BLOBMSG_TYPE_STRING }, +     [TUNNEL_ATTR_ID] = { .name = "id", .type =
>>>> BLOBMSG_TYPE_INT32 }, +      [TUNNEL_ATTR_PORT] = { .name = "port", .type =
>>>> BLOBMSG_TYPE_INT32 }, +      [TUNNEL_ATTR_MACADDR] = { .name = "macaddr", .type
>>>> = BLOBMSG_TYPE_STRING }, };
>>>>
>>>>  const struct uci_blob_param_list tunnel_attr_list = {
>>>> diff --git a/system.h b/system.h
>>>> index 6077b95..2c4df38 100644
>>>> --- a/system.h
>>>> +++ b/system.h
>>>> @@ -35,6 +35,9 @@ enum tunnel_param {
>>>>      TUNNEL_ATTR_LINK,
>>>>      TUNNEL_ATTR_FMRS,
>>>>      TUNNEL_ATTR_INFO,
>>>> +    TUNNEL_ATTR_ID,
>>>> +    TUNNEL_ATTR_PORT,
>>>> +    TUNNEL_ATTR_MACADDR,
>>> GRE specific parameters like  ikey, okey, icsum, ocum, iseqno, oseqno were put
>>> into the TUNNEL_ATTR_INFO parameter to avoid to define too much tunnel protocol
>>> specific attributes definitions. Maybe it's possible to use the same approach
>>> for the vxlan specific parameters like id, port, macaddr ?
>>> Otherwise the rest looks of for me.
>>
>> Kinda seems to me like defeating the purpose of having a blobmsg for
>> this... Munching everything together into a single string feels more
>> acceptable to me for simple on/off flags than for more complex data like
>> numbers and MAC addresses, but I think I wouldn't have chosen such a
>> solution in any case.
> Choice was based on a tradeoff between a continuously growing tunnel
> attribute list with protocol specific unrelated parameters or trying
> to get a bit of structure in the different tunnel protocol parameters.
> Having said that I'm open for other suggestions
I think I prefer the growing tunnel attribute list over weird and
seemingly arbitrary stuffing of attributes into a single string.

- Felix




More information about the Lede-dev mailing list