Add a netlink interface to manage the TX TLV parameters. Managed parameters include those for validating and sending TLVs being sent such as alignment, TLV ordering, length limits, etc. --- include/net/ipv6.h | 9 +- include/uapi/linux/in6.h | 31 ++++ net/ipv6/exthdrs_core.c | 362 ++++++++++++++++++++++++++++++++++++++++++++- net/ipv6/exthdrs_options.c | 10 +- 4 files changed, 401 insertions(+), 11 deletions(-)
diff --git a/include/net/ipv6.h b/include/net/ipv6.h index 9b25d08..3d2995f 100644 --- a/include/net/ipv6.h +++ b/include/net/ipv6.h @@ -17,6 +17,7 @@ #include <linux/hardirq.h> #include <linux/jhash.h> #include <linux/refcount.h> +#include <net/genetlink.h> #include <net/if_inet6.h> #include <net/ndisc.h> #include <net/flow.h> @@ -450,9 +451,11 @@ int tlv_unset_params(struct tlv_param_table *tlv_param_table, unsigned char type); int exthdrs_init(struct tlv_param_table *tlv_param_table, - const struct tlv_proc_init *init_params, - int num_init_params); -void exthdrs_fini(struct tlv_param_table *tlv_param_table); + const struct tlv_proc_init *tlv_init_params, int proto, + int num_init_params, struct genl_family *tlv_genl_family, + char *tlv_genl_name, int tlv_genl_version); +void exthdrs_fini(struct tlv_param_table *tlv_param_table, + struct genl_family *tlv_nl_family); /* tlv_get_proc assumes rcu_read_lock is held */ static inline struct tlv_proc *tlv_get_proc( diff --git a/include/uapi/linux/in6.h b/include/uapi/linux/in6.h index 6a99ee1..1c79361 100644 --- a/include/uapi/linux/in6.h +++ b/include/uapi/linux/in6.h @@ -306,6 +306,37 @@ struct in6_flowlabel_req { #define IPV6_TLV_CLASS_ANY_DSTOPT (IPV6_TLV_CLASS_FLAG_RTRDSTOPT | \ IPV6_TLV_CLASS_FLAG_DSTOPT) +/* NETLINK_GENERIC related info for IPv6 TLVs */ + +#define IPV6_TLV_GENL_NAME "ipv6-tlv" +#define IPV6_TLV_GENL_VERSION 0x1 + +enum { + IPV6_TLV_ATTR_UNSPEC, + IPV6_TLV_ATTR_TYPE, /* u8, > 1 */ + IPV6_TLV_ATTR_ORDER, /* u8 */ + IPV6_TLV_ATTR_ADMIN_PERM, /* u8, perm value */ + IPV6_TLV_ATTR_USER_PERM, /* u8, perm value */ + IPV6_TLV_ATTR_CLASS, /* u8, 3 bit flags */ + IPV6_TLV_ATTR_ALIGN_MULT, /* u8, 1 to 16 */ + IPV6_TLV_ATTR_ALIGN_OFF, /* u8, 0 to 15 */ + IPV6_TLV_ATTR_MIN_DATA_LEN, /* u8 (option data length) */ + IPV6_TLV_ATTR_MAX_DATA_LEN, /* u8 (option data length) */ + IPV6_TLV_ATTR_DATA_LEN_MULT, /* u8, 1 to 16 */ + IPV6_TLV_ATTR_DATA_LEN_OFF, /* u8, 0 to 15 */ + + __IPV6_TLV_ATTR_MAX, +}; + +#define IPV6_TLV_ATTR_MAX (__IPV6_TLV_ATTR_MAX - 1) + +enum { + IPV6_TLV_CMD_SET, + IPV6_TLV_CMD_UNSET, + IPV6_TLV_CMD_GET, + + __IPV6_TLV_CMD_MAX, +}; /* TLV permissions values */ enum { diff --git a/net/ipv6/exthdrs_core.c b/net/ipv6/exthdrs_core.c index 98b5bc1..09799bcd 100644 --- a/net/ipv6/exthdrs_core.c +++ b/net/ipv6/exthdrs_core.c @@ -3,7 +3,9 @@ * not configured or static. */ #include <linux/export.h> +#include <net/genetlink.h> #include <net/ipv6.h> +#include <uapi/linux/genetlink.h> /* * find out if nexthdr is a well-known extension header or a protocol @@ -657,14 +659,341 @@ int tlv_unset_params(struct tlv_param_table *tlv_param_table, } EXPORT_SYMBOL(tlv_unset_params); +static const struct nla_policy tlv_nl_policy[IPV6_TLV_ATTR_MAX + 1] = { + [IPV6_TLV_ATTR_TYPE] = { .type = NLA_U8, }, + [IPV6_TLV_ATTR_ORDER] = { .type = NLA_U8, }, + [IPV6_TLV_ATTR_ADMIN_PERM] = { .type = NLA_U8, }, + [IPV6_TLV_ATTR_USER_PERM] = { .type = NLA_U8, }, + [IPV6_TLV_ATTR_CLASS] = { .type = NLA_U8, }, + [IPV6_TLV_ATTR_ALIGN_MULT] = { .type = NLA_U8, }, + [IPV6_TLV_ATTR_ALIGN_OFF] = { .type = NLA_U8, }, + [IPV6_TLV_ATTR_MIN_DATA_LEN] = { .type = NLA_U8, }, + [IPV6_TLV_ATTR_MAX_DATA_LEN] = { .type = NLA_U8, }, + [IPV6_TLV_ATTR_DATA_LEN_OFF] = { .type = NLA_U8, }, + [IPV6_TLV_ATTR_DATA_LEN_MULT] = { .type = NLA_U8, }, +}; + +static int tlv_nl_cmd_set(struct tlv_param_table *tlv_param_table, + struct genl_family *tlv_nl_family, + struct sk_buff *skb, struct genl_info *info) +{ + struct tlv_params new_params; + struct tlv_tx_params *tptx; + struct tlv_proc *tproc; + int retv = -EINVAL, i; + u8 tlv_type, v; + + if (!info->attrs[IPV6_TLV_ATTR_TYPE]) + return -EINVAL; + + tlv_type = nla_get_u8(info->attrs[IPV6_TLV_ATTR_TYPE]); + if (tlv_type < 2) + return -EINVAL; + + rcu_read_lock(); + + /* Base new parameters on existing ones */ + tproc = tlv_get_proc(tlv_param_table, tlv_type); + new_params = tproc->params; + + if (info->attrs[IPV6_TLV_ATTR_ORDER]) { + v = nla_get_u8(info->attrs[IPV6_TLV_ATTR_ORDER]); + if (v) { + for (i = 2; i < 256; i++) { + tproc = tlv_get_proc(tlv_param_table, i); + tptx = &tproc->params.t; + + /* Preferred orders must be unique */ + if (tptx->preferred_order == v && + i != tlv_type) { + retv = -EALREADY; + goto out; + } + } + new_params.t.preferred_order = v; + } + } + + if (!new_params.t.preferred_order) { + unsigned long check_map[BITS_TO_LONGS(255)]; + int pos; + + /* Preferred order not specified, automatically set one. + * This is chosen to be the first value after the greatest + * order in use. + */ + memset(check_map, 0, sizeof(check_map)); + + for (i = 2; i < 256; i++) { + unsigned int order; + + tproc = tlv_get_proc(tlv_param_table, i); + tptx = &tproc->params.t; + order = tptx->preferred_order; + + if (!order) + continue; + + WARN_ON(test_bit(255 - order, check_map)); + set_bit(255 - order, check_map); + } + + pos = find_first_bit(check_map, 255); + if (pos) + new_params.t.preferred_order = 255 - (pos - 1); + else + new_params.t.preferred_order = 255 - + find_first_zero_bit(check_map, sizeof(check_map)); + } + + if (info->attrs[IPV6_TLV_ATTR_ADMIN_PERM]) { + v = nla_get_u8(info->attrs[IPV6_TLV_ATTR_ADMIN_PERM]); + if (v > IPV6_TLV_PERM_MAX) + goto out; + new_params.t.admin_perm = v; + } + + if (info->attrs[IPV6_TLV_ATTR_USER_PERM]) { + v = nla_get_u8(info->attrs[IPV6_TLV_ATTR_USER_PERM]); + if (v > IPV6_TLV_PERM_MAX) + goto out; + new_params.t.user_perm = v; + } + + if (info->attrs[IPV6_TLV_ATTR_CLASS]) { + v = nla_get_u8(info->attrs[IPV6_TLV_ATTR_CLASS]); + if (v > IPV6_TLV_CLASS_MAX) + goto out; + new_params.t.class = v; + } + + if (info->attrs[IPV6_TLV_ATTR_ALIGN_MULT]) { + v = nla_get_u8(info->attrs[IPV6_TLV_ATTR_ALIGN_MULT]); + if (v > 16 || v < 1) + goto out; + new_params.t.align_mult = v - 1; + } + + if (info->attrs[IPV6_TLV_ATTR_ALIGN_OFF]) { + v = nla_get_u8(info->attrs[IPV6_TLV_ATTR_ALIGN_OFF]); + if (v > 15) + goto out; + new_params.t.align_off = v; + } + + if (info->attrs[IPV6_TLV_ATTR_MAX_DATA_LEN]) + new_params.t.max_data_len = + nla_get_u8(info->attrs[IPV6_TLV_ATTR_MAX_DATA_LEN]); + + if (info->attrs[IPV6_TLV_ATTR_MIN_DATA_LEN]) + new_params.t.min_data_len = + nla_get_u8(info->attrs[IPV6_TLV_ATTR_MIN_DATA_LEN]); + + if (info->attrs[IPV6_TLV_ATTR_DATA_LEN_MULT]) { + v = nla_get_u8(info->attrs[IPV6_TLV_ATTR_DATA_LEN_MULT]); + if (v > 16 || v < 1) + goto out; + new_params.t.data_len_mult = v - 1; + } + + if (info->attrs[IPV6_TLV_ATTR_DATA_LEN_OFF]) { + v = nla_get_u8(info->attrs[IPV6_TLV_ATTR_DATA_LEN_OFF]); + if (v > 15) + goto out; + new_params.t.data_len_off = v; + } + + retv = tlv_set_params(tlv_param_table, tlv_type, &new_params); + +out: + rcu_read_unlock(); + return retv; +} + +static int tlv_nl_cmd_unset(struct tlv_param_table *tlv_param_table, + struct genl_family *tlv_nl_family, + struct sk_buff *skb, struct genl_info *info) +{ + unsigned int tlv_type; + + if (!info->attrs[IPV6_TLV_ATTR_TYPE]) + return -EINVAL; + + tlv_type = nla_get_u8(info->attrs[IPV6_TLV_ATTR_TYPE]); + if (tlv_type < 2) + return -EINVAL; + + return tlv_unset_params(tlv_param_table, tlv_type); +} + +static int tlv_fill_info(struct tlv_param_table *tlv_param_table, + int tlv_type, struct sk_buff *msg, bool admin) +{ + struct tlv_proc *tproc; + struct tlv_params *tp; + int ret = 0; + + rcu_read_lock(); + + tproc = tlv_get_proc(tlv_param_table, tlv_type); + tp = &tproc->params; + + if (nla_put_u8(msg, IPV6_TLV_ATTR_TYPE, tlv_type) || + nla_put_u8(msg, IPV6_TLV_ATTR_ORDER, tp->t.preferred_order) || + nla_put_u8(msg, IPV6_TLV_ATTR_USER_PERM, tp->t.user_perm) || + (admin && nla_put_u8(msg, IPV6_TLV_ATTR_ADMIN_PERM, + tp->t.admin_perm)) || + nla_put_u8(msg, IPV6_TLV_ATTR_CLASS, tp->t.class) || + nla_put_u8(msg, IPV6_TLV_ATTR_ALIGN_MULT, tp->t.align_mult + 1) || + nla_put_u8(msg, IPV6_TLV_ATTR_ALIGN_OFF, tp->t.align_off) || + nla_put_u8(msg, IPV6_TLV_ATTR_MIN_DATA_LEN, tp->t.min_data_len) || + nla_put_u8(msg, IPV6_TLV_ATTR_MAX_DATA_LEN, tp->t.max_data_len) || + nla_put_u8(msg, IPV6_TLV_ATTR_DATA_LEN_MULT, + tp->t.data_len_mult + 1) || + nla_put_u8(msg, IPV6_TLV_ATTR_DATA_LEN_OFF, tp->t.data_len_off)) + ret = -1; + + rcu_read_unlock(); + + return ret; +} + +static int tlv_dump_info(struct tlv_param_table *tlv_param_table, + struct genl_family *tlv_nl_family, + int tlv_type, u32 portid, u32 seq, u32 flags, + struct sk_buff *skb, u8 cmd, bool admin) +{ + void *hdr; + + hdr = genlmsg_put(skb, portid, seq, tlv_nl_family, flags, cmd); + if (!hdr) + return -ENOMEM; + + if (tlv_fill_info(tlv_param_table, tlv_type, skb, admin) < 0) { + genlmsg_cancel(skb, hdr); + return -EMSGSIZE; + } + + genlmsg_end(skb, hdr); + + return 0; +} + +static int tlv_nl_cmd_get(struct tlv_param_table *tlv_param_table, + struct genl_family *tlv_nl_family, + struct sk_buff *skb, struct genl_info *info) +{ + struct sk_buff *msg; + int ret, tlv_type; + + if (!info->attrs[IPV6_TLV_ATTR_TYPE]) + return -EINVAL; + + tlv_type = nla_get_u8(info->attrs[IPV6_TLV_ATTR_TYPE]); + if (tlv_type < 2) + return -EINVAL; + + msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); + if (!msg) + return -ENOMEM; + + ret = tlv_dump_info(tlv_param_table, tlv_nl_family, + tlv_type, info->snd_portid, info->snd_seq, 0, msg, + info->genlhdr->cmd, + netlink_capable(skb, CAP_NET_ADMIN)); + if (ret < 0) { + nlmsg_free(msg); + return ret; + } + + return genlmsg_reply(msg, info); +} + +static int tlv_nl_dump(struct tlv_param_table *tlv_param_table, + struct genl_family *tlv_nl_family, + struct sk_buff *skb, struct netlink_callback *cb) +{ + int idx = 0, ret, i; + + for (i = 2; i < 256; i++) { + if (idx++ < cb->args[0]) + continue; + ret = tlv_dump_info(tlv_param_table, tlv_nl_family, i, + NETLINK_CB(cb->skb).portid, + cb->nlh->nlmsg_seq, NLM_F_MULTI, + skb, IPV6_TLV_CMD_GET, + netlink_capable(cb->skb, CAP_NET_ADMIN)); + if (ret) + break; + } + + cb->args[0] = idx; + return skb->len; +} + +extern struct genl_family ipv6_tlv_nl_family; + +static int ipv6_tlv_nl_cmd_set(struct sk_buff *skb, struct genl_info *info) +{ + return tlv_nl_cmd_set(&ipv6_tlv_param_table, &ipv6_tlv_nl_family, + skb, info); +} + +static int ipv6_tlv_nl_cmd_unset(struct sk_buff *skb, struct genl_info *info) +{ + return tlv_nl_cmd_unset(&ipv6_tlv_param_table, &ipv6_tlv_nl_family, + skb, info); +} + +static int ipv6_tlv_nl_cmd_get(struct sk_buff *skb, struct genl_info *info) +{ + return tlv_nl_cmd_get(&ipv6_tlv_param_table, &ipv6_tlv_nl_family, + skb, info); +} + +static int ipv6_tlv_nl_dump(struct sk_buff *skb, struct netlink_callback *cb) +{ + return tlv_nl_dump(&ipv6_tlv_param_table, &ipv6_tlv_nl_family, + skb, cb); +} + +static const struct genl_ops ipv6_tlv_nl_ops[] = { +{ + .cmd = IPV6_TLV_CMD_SET, + .doit = ipv6_tlv_nl_cmd_set, + .flags = GENL_ADMIN_PERM, +}, +{ + .cmd = IPV6_TLV_CMD_UNSET, + .doit = ipv6_tlv_nl_cmd_unset, + .flags = GENL_ADMIN_PERM, +}, +{ + .cmd = IPV6_TLV_CMD_GET, + .doit = ipv6_tlv_nl_cmd_get, + .dumpit = ipv6_tlv_nl_dump, +}, +}; + int exthdrs_init(struct tlv_param_table *tlv_param_table, - const struct tlv_proc_init *tlv_init_params, - int num_init_params) + const struct tlv_proc_init *tlv_init_params, int proto, + int num_init_params, struct genl_family *tlv_nl_family, + char tlv_genl_name[], int tlv_genl_version) { unsigned long check_map[BITS_TO_LONGS(256)]; + const struct genl_ops *tlv_nl_ops; struct tlv_param_table_data *tpt; - size_t tsize; - int i; + size_t tsize, ops_size; + int i, ret; + + switch (proto) { + case ETH_P_IPV6: + tlv_nl_ops = ipv6_tlv_nl_ops; + ops_size = ARRAY_SIZE(ipv6_tlv_nl_ops); + break; + default: + return -EPROTONOSUPPORT; + } memset(check_map, 0, sizeof(check_map)); @@ -708,12 +1037,35 @@ int exthdrs_init(struct tlv_param_table *tlv_param_table, RCU_INIT_POINTER(tlv_param_table->data, tpt); + memset(tlv_nl_family, 0, sizeof(*tlv_nl_family)); + + tlv_nl_family->hdrsize = 0; + strncpy(tlv_nl_family->name, tlv_genl_name, GENL_NAMSIZ); + tlv_nl_family->version = tlv_genl_version; + tlv_nl_family->maxattr = IPV6_TLV_ATTR_MAX; + tlv_nl_family->netnsok = true; + tlv_nl_family->module = THIS_MODULE; + tlv_nl_family->ops = tlv_nl_ops; + tlv_nl_family->policy = tlv_nl_policy; + tlv_nl_family->n_ops = ops_size; + + ret = genl_register_family(tlv_nl_family); + if (ret < 0) + goto fail_genl_register; + return 0; + +fail_genl_register: + __tlv_destroy_param_table(tlv_param_table); + + return ret; } EXPORT_SYMBOL(exthdrs_init); -void exthdrs_fini(struct tlv_param_table *tlv_param_table) +void exthdrs_fini(struct tlv_param_table *tlv_param_table, + struct genl_family *tlv_nl_family) { __tlv_destroy_param_table(tlv_param_table); + genl_unregister_family(tlv_nl_family); } EXPORT_SYMBOL(exthdrs_fini); diff --git a/net/ipv6/exthdrs_options.c b/net/ipv6/exthdrs_options.c index b316143..607a8c2 100644 --- a/net/ipv6/exthdrs_options.c +++ b/net/ipv6/exthdrs_options.c @@ -6,6 +6,7 @@ #include <linux/socket.h> #include <linux/types.h> #include <net/calipso.h> +#include <net/genetlink.h> #include <net/ipv6.h> #include <net/ip6_route.h> #if IS_ENABLED(CONFIG_IPV6_MIP6) @@ -251,17 +252,20 @@ static const struct tlv_proc_init tlv_init_params[] __initconst = { }, }; +struct genl_family ipv6_tlv_nl_family __ro_after_init; struct tlv_param_table __rcu ipv6_tlv_param_table; static int __init ipv6_exthdrs_init(void) { - return exthdrs_init(&ipv6_tlv_param_table, tlv_init_params, - ARRAY_SIZE(tlv_init_params)); + return exthdrs_init(&ipv6_tlv_param_table, tlv_init_params, ETH_P_IPV6, + ARRAY_SIZE(tlv_init_params), + &ipv6_tlv_nl_family, IPV6_TLV_GENL_NAME, + IPV6_TLV_GENL_VERSION); } module_init(ipv6_exthdrs_init); static void __exit ipv6_exthdrs_fini(void) { - exthdrs_fini(&ipv6_tlv_param_table); + exthdrs_fini(&ipv6_tlv_param_table, &ipv6_tlv_nl_family); } module_exit(ipv6_exthdrs_fini); -- 2.7.4