diff options
| -rw-r--r-- | Documentation/networking/mpls-sysctl.txt | 20 | ||||
| -rw-r--r-- | include/net/netns/mpls.h | 2 | ||||
| -rw-r--r-- | net/mpls/af_mpls.c | 146 |
3 files changed, 168 insertions, 0 deletions
diff --git a/Documentation/networking/mpls-sysctl.txt b/Documentation/networking/mpls-sysctl.txt new file mode 100644 index 000000000000..639ddf0ece9b --- /dev/null +++ b/Documentation/networking/mpls-sysctl.txt @@ -0,0 +1,20 @@ +/proc/sys/net/mpls/* Variables: + +platform_labels - INTEGER + Number of entries in the platform label table. It is not + possible to configure forwarding for label values equal to or + greater than the number of platform labels. + + A dense utliziation of the entries in the platform label table + is possible and expected aas the platform labels are locally + allocated. + + If the number of platform label table entries is set to 0 no + label will be recognized by the kernel and mpls forwarding + will be disabled. + + Reducing this value will remove all label routing entries that + no longer fit in the table. + + Possible values: 0 - 1048575 + Default: 0 diff --git a/include/net/netns/mpls.h b/include/net/netns/mpls.h index f90aaf8d4f89..d29203651c01 100644 --- a/include/net/netns/mpls.h +++ b/include/net/netns/mpls.h @@ -6,10 +6,12 @@ #define __NETNS_MPLS_H__ struct mpls_route; +struct ctl_table_header; struct netns_mpls { size_t platform_labels; struct mpls_route __rcu * __rcu *platform_label; + struct ctl_table_header *ctl; }; #endif /* __NETNS_MPLS_H__ */ diff --git a/net/mpls/af_mpls.c b/net/mpls/af_mpls.c index 924377736b2a..b097125dfa33 100644 --- a/net/mpls/af_mpls.c +++ b/net/mpls/af_mpls.c @@ -1,6 +1,7 @@ #include <linux/types.h> #include <linux/skbuff.h> #include <linux/socket.h> +#include <linux/sysctl.h> #include <linux/net.h> #include <linux/module.h> #include <linux/if_arp.h> @@ -31,6 +32,9 @@ struct mpls_route { /* next hop label forwarding entry */ u8 rt_via[0]; }; +static int zero = 0; +static int label_limit = (1 << 20) - 1; + static struct mpls_route *mpls_route_input_rcu(struct net *net, unsigned index) { struct mpls_route *rt = NULL; @@ -273,18 +277,160 @@ static struct notifier_block mpls_dev_notifier = { .notifier_call = mpls_dev_notify, }; +static int resize_platform_label_table(struct net *net, size_t limit) +{ + size_t size = sizeof(struct mpls_route *) * limit; + size_t old_limit; + size_t cp_size; + struct mpls_route __rcu **labels = NULL, **old; + struct mpls_route *rt0 = NULL, *rt2 = NULL; + unsigned index; + + if (size) { + labels = kzalloc(size, GFP_KERNEL | __GFP_NOWARN | __GFP_NORETRY); + if (!labels) + labels = vzalloc(size); + + if (!labels) + goto nolabels; + } + + /* In case the predefined labels need to be populated */ + if (limit > LABEL_IPV4_EXPLICIT_NULL) { + struct net_device *lo = net->loopback_dev; + rt0 = mpls_rt_alloc(lo->addr_len); + if (!rt0) + goto nort0; + rt0->rt_dev = lo; + rt0->rt_protocol = RTPROT_KERNEL; + rt0->rt_via_family = AF_PACKET; + memcpy(rt0->rt_via, lo->dev_addr, lo->addr_len); + } + if (limit > LABEL_IPV6_EXPLICIT_NULL) { + struct net_device *lo = net->loopback_dev; + rt2 = mpls_rt_alloc(lo->addr_len); + if (!rt2) + goto nort2; + rt2->rt_dev = lo; + rt2->rt_protocol = RTPROT_KERNEL; + rt2->rt_via_family = AF_PACKET; + memcpy(rt2->rt_via, lo->dev_addr, lo->addr_len); + } + + rtnl_lock(); + /* Remember the original table */ + old = net->mpls.platform_label; + old_limit = net->mpls.platform_labels; + + /* Free any labels beyond the new table */ + for (index = limit; index < old_limit; index++) + mpls_route_update(net, index, NULL, NULL, NULL); + + /* Copy over the old labels */ + cp_size = size; + if (old_limit < limit) + cp_size = old_limit * sizeof(struct mpls_route *); + + memcpy(labels, old, cp_size); + + /* If needed set the predefined labels */ + if ((old_limit <= LABEL_IPV6_EXPLICIT_NULL) && + (limit > LABEL_IPV6_EXPLICIT_NULL)) { + labels[LABEL_IPV6_EXPLICIT_NULL] = rt2; + rt2 = NULL; + } + + if ((old_limit <= LABEL_IPV4_EXPLICIT_NULL) && + (limit > LABEL_IPV4_EXPLICIT_NULL)) { + labels[LABEL_IPV4_EXPLICIT_NULL] = rt0; + rt0 = NULL; + } + + /* Update the global pointers */ + net->mpls.platform_labels = limit; + net->mpls.platform_label = labels; + + rtnl_unlock(); + + mpls_rt_free(rt2); + mpls_rt_free(rt0); + + if (old) { + synchronize_rcu(); + kvfree(old); + } + return 0; + +nort2: + mpls_rt_free(rt0); +nort0: + kvfree(labels); +nolabels: + return -ENOMEM; +} + +static int mpls_platform_labels(struct ctl_table *table, int write, + void __user *buffer, size_t *lenp, loff_t *ppos) +{ + struct net *net = table->data; + int platform_labels = net->mpls.platform_labels; + int ret; + struct ctl_table tmp = { + .procname = table->procname, + .data = &platform_labels, + .maxlen = sizeof(int), + .mode = table->mode, + .extra1 = &zero, + .extra2 = &label_limit, + }; + + ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos); + + if (write && ret == 0) + ret = resize_platform_label_table(net, platform_labels); + + return ret; +} + +static struct ctl_table mpls_table[] = { + { + .procname = "platform_labels", + .data = NULL, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = mpls_platform_labels, + }, + { } +}; + static int mpls_net_init(struct net *net) { + struct ctl_table *table; + net->mpls.platform_labels = 0; net->mpls.platform_label = NULL; + table = kmemdup(mpls_table, sizeof(mpls_table), GFP_KERNEL); + if (table == NULL) + return -ENOMEM; + + table[0].data = net; + net->mpls.ctl = register_net_sysctl(net, "net/mpls", table); + if (net->mpls.ctl == NULL) + return -ENOMEM; + return 0; } static void mpls_net_exit(struct net *net) { + struct ctl_table *table; unsigned int index; + table = net->mpls.ctl->ctl_table_arg; + unregister_net_sysctl_table(net->mpls.ctl); + kfree(table); + /* An rcu grace period haselapsed since there was a device in * the network namespace (and thus the last in fqlight packet) * left this network namespace. This is because |