| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * test/set flag bits stored in conntrack extension area. |
| * |
| * (C) 2013 Astaro GmbH & Co KG |
| */ |
| |
| #include <linux/export.h> |
| #include <linux/types.h> |
| |
| #include <net/netfilter/nf_conntrack_ecache.h> |
| #include <net/netfilter/nf_conntrack_labels.h> |
| |
| static DEFINE_SPINLOCK(nf_connlabels_lock); |
| |
| static int replace_u32(u32 *address, u32 mask, u32 new) |
| { |
| u32 old, tmp; |
| |
| do { |
| old = *address; |
| tmp = (old & mask) ^ new; |
| if (old == tmp) |
| return 0; |
| } while (cmpxchg(address, old, tmp) != old); |
| |
| return 1; |
| } |
| |
| int nf_connlabels_replace(struct nf_conn *ct, |
| const u32 *data, |
| const u32 *mask, unsigned int words32) |
| { |
| struct nf_conn_labels *labels; |
| unsigned int size, i; |
| int changed = 0; |
| u32 *dst; |
| |
| labels = nf_ct_labels_find(ct); |
| if (!labels) |
| return -ENOSPC; |
| |
| size = sizeof(labels->bits); |
| if (size < (words32 * sizeof(u32))) |
| words32 = size / sizeof(u32); |
| |
| dst = (u32 *) labels->bits; |
| for (i = 0; i < words32; i++) |
| changed |= replace_u32(&dst[i], mask ? ~mask[i] : 0, data[i]); |
| |
| size /= sizeof(u32); |
| for (i = words32; i < size; i++) /* pad */ |
| replace_u32(&dst[i], 0, 0); |
| |
| if (changed) |
| nf_conntrack_event_cache(IPCT_LABEL, ct); |
| return 0; |
| } |
| EXPORT_SYMBOL_GPL(nf_connlabels_replace); |
| |
| int nf_connlabels_get(struct net *net, unsigned int bits) |
| { |
| if (BIT_WORD(bits) >= NF_CT_LABELS_MAX_SIZE / sizeof(long)) |
| return -ERANGE; |
| |
| spin_lock(&nf_connlabels_lock); |
| net->ct.labels_used++; |
| spin_unlock(&nf_connlabels_lock); |
| |
| return 0; |
| } |
| EXPORT_SYMBOL_GPL(nf_connlabels_get); |
| |
| void nf_connlabels_put(struct net *net) |
| { |
| spin_lock(&nf_connlabels_lock); |
| net->ct.labels_used--; |
| spin_unlock(&nf_connlabels_lock); |
| } |
| EXPORT_SYMBOL_GPL(nf_connlabels_put); |
| |
| static const struct nf_ct_ext_type labels_extend = { |
| .len = sizeof(struct nf_conn_labels), |
| .align = __alignof__(struct nf_conn_labels), |
| .id = NF_CT_EXT_LABELS, |
| }; |
| |
| int nf_conntrack_labels_init(void) |
| { |
| BUILD_BUG_ON(NF_CT_LABELS_MAX_SIZE / sizeof(long) >= U8_MAX); |
| |
| return nf_ct_extend_register(&labels_extend); |
| } |
| |
| void nf_conntrack_labels_fini(void) |
| { |
| nf_ct_extend_unregister(&labels_extend); |
| } |