Florian Westphal | c539f01 | 2013-01-11 06:30:44 +0000 | [diff] [blame] | 1 | /* |
| 2 | * test/set flag bits stored in conntrack extension area. |
| 3 | * |
| 4 | * (C) 2013 Astaro GmbH & Co KG |
| 5 | * |
| 6 | * This program is free software; you can redistribute it and/or modify |
| 7 | * it under the terms of the GNU General Public License version 2 as |
| 8 | * published by the Free Software Foundation. |
| 9 | */ |
| 10 | |
Florian Westphal | c539f01 | 2013-01-11 06:30:44 +0000 | [diff] [blame] | 11 | #include <linux/export.h> |
Florian Westphal | c539f01 | 2013-01-11 06:30:44 +0000 | [diff] [blame] | 12 | #include <linux/types.h> |
Florian Westphal | c539f01 | 2013-01-11 06:30:44 +0000 | [diff] [blame] | 13 | |
| 14 | #include <net/netfilter/nf_conntrack_ecache.h> |
| 15 | #include <net/netfilter/nf_conntrack_labels.h> |
| 16 | |
Joe Stringer | 86ca02e | 2015-08-26 11:31:51 -0700 | [diff] [blame] | 17 | static spinlock_t nf_connlabels_lock; |
| 18 | |
Florian Westphal | c539f01 | 2013-01-11 06:30:44 +0000 | [diff] [blame] | 19 | static unsigned int label_bits(const struct nf_conn_labels *l) |
| 20 | { |
| 21 | unsigned int longs = l->words; |
| 22 | return longs * BITS_PER_LONG; |
| 23 | } |
| 24 | |
| 25 | bool nf_connlabel_match(const struct nf_conn *ct, u16 bit) |
| 26 | { |
| 27 | struct nf_conn_labels *labels = nf_ct_labels_find(ct); |
| 28 | |
| 29 | if (!labels) |
| 30 | return false; |
| 31 | |
| 32 | return bit < label_bits(labels) && test_bit(bit, labels->bits); |
| 33 | } |
| 34 | EXPORT_SYMBOL_GPL(nf_connlabel_match); |
| 35 | |
| 36 | int nf_connlabel_set(struct nf_conn *ct, u16 bit) |
| 37 | { |
| 38 | struct nf_conn_labels *labels = nf_ct_labels_find(ct); |
| 39 | |
| 40 | if (!labels || bit >= label_bits(labels)) |
| 41 | return -ENOSPC; |
| 42 | |
| 43 | if (test_bit(bit, labels->bits)) |
| 44 | return 0; |
| 45 | |
Florian Westphal | 797a7d6 | 2013-06-21 16:51:30 +0200 | [diff] [blame] | 46 | if (!test_and_set_bit(bit, labels->bits)) |
Florian Westphal | 0ceabd8 | 2013-01-11 06:30:45 +0000 | [diff] [blame] | 47 | nf_conntrack_event_cache(IPCT_LABEL, ct); |
Florian Westphal | c539f01 | 2013-01-11 06:30:44 +0000 | [diff] [blame] | 48 | |
| 49 | return 0; |
| 50 | } |
| 51 | EXPORT_SYMBOL_GPL(nf_connlabel_set); |
| 52 | |
Florian Westphal | 9b21f6a | 2013-01-11 06:30:46 +0000 | [diff] [blame] | 53 | static void replace_u32(u32 *address, u32 mask, u32 new) |
| 54 | { |
| 55 | u32 old, tmp; |
| 56 | |
| 57 | do { |
| 58 | old = *address; |
| 59 | tmp = (old & mask) ^ new; |
| 60 | } while (cmpxchg(address, old, tmp) != old); |
| 61 | } |
| 62 | |
| 63 | int nf_connlabels_replace(struct nf_conn *ct, |
| 64 | const u32 *data, |
| 65 | const u32 *mask, unsigned int words32) |
| 66 | { |
| 67 | struct nf_conn_labels *labels; |
| 68 | unsigned int size, i; |
| 69 | u32 *dst; |
| 70 | |
| 71 | labels = nf_ct_labels_find(ct); |
| 72 | if (!labels) |
| 73 | return -ENOSPC; |
| 74 | |
| 75 | size = labels->words * sizeof(long); |
| 76 | if (size < (words32 * sizeof(u32))) |
| 77 | words32 = size / sizeof(u32); |
| 78 | |
| 79 | dst = (u32 *) labels->bits; |
| 80 | if (words32) { |
| 81 | for (i = 0; i < words32; i++) |
| 82 | replace_u32(&dst[i], mask ? ~mask[i] : 0, data[i]); |
| 83 | } |
| 84 | |
| 85 | size /= sizeof(u32); |
| 86 | for (i = words32; i < size; i++) /* pad */ |
| 87 | replace_u32(&dst[i], 0, 0); |
| 88 | |
| 89 | nf_conntrack_event_cache(IPCT_LABEL, ct); |
| 90 | return 0; |
| 91 | } |
| 92 | EXPORT_SYMBOL_GPL(nf_connlabels_replace); |
Florian Westphal | 9b21f6a | 2013-01-11 06:30:46 +0000 | [diff] [blame] | 93 | |
Joe Stringer | 86ca02e | 2015-08-26 11:31:51 -0700 | [diff] [blame] | 94 | int nf_connlabels_get(struct net *net, unsigned int n_bits) |
| 95 | { |
| 96 | size_t words; |
| 97 | |
| 98 | if (n_bits > (NF_CT_LABELS_MAX_SIZE * BITS_PER_BYTE)) |
| 99 | return -ERANGE; |
| 100 | |
| 101 | words = BITS_TO_LONGS(n_bits); |
| 102 | |
| 103 | spin_lock(&nf_connlabels_lock); |
| 104 | net->ct.labels_used++; |
| 105 | if (words > net->ct.label_words) |
| 106 | net->ct.label_words = words; |
| 107 | spin_unlock(&nf_connlabels_lock); |
| 108 | |
| 109 | return 0; |
| 110 | } |
| 111 | EXPORT_SYMBOL_GPL(nf_connlabels_get); |
| 112 | |
| 113 | void nf_connlabels_put(struct net *net) |
| 114 | { |
| 115 | spin_lock(&nf_connlabels_lock); |
| 116 | net->ct.labels_used--; |
| 117 | if (net->ct.labels_used == 0) |
| 118 | net->ct.label_words = 0; |
| 119 | spin_unlock(&nf_connlabels_lock); |
| 120 | } |
| 121 | EXPORT_SYMBOL_GPL(nf_connlabels_put); |
| 122 | |
Florian Westphal | c539f01 | 2013-01-11 06:30:44 +0000 | [diff] [blame] | 123 | static struct nf_ct_ext_type labels_extend __read_mostly = { |
| 124 | .len = sizeof(struct nf_conn_labels), |
| 125 | .align = __alignof__(struct nf_conn_labels), |
| 126 | .id = NF_CT_EXT_LABELS, |
| 127 | }; |
| 128 | |
Gao feng | 5f69b8f | 2013-01-21 22:10:31 +0000 | [diff] [blame] | 129 | int nf_conntrack_labels_init(void) |
Florian Westphal | c539f01 | 2013-01-11 06:30:44 +0000 | [diff] [blame] | 130 | { |
Joe Stringer | 86ca02e | 2015-08-26 11:31:51 -0700 | [diff] [blame] | 131 | spin_lock_init(&nf_connlabels_lock); |
Gao feng | 5f69b8f | 2013-01-21 22:10:31 +0000 | [diff] [blame] | 132 | return nf_ct_extend_register(&labels_extend); |
Florian Westphal | c539f01 | 2013-01-11 06:30:44 +0000 | [diff] [blame] | 133 | } |
| 134 | |
Gao feng | 5f69b8f | 2013-01-21 22:10:31 +0000 | [diff] [blame] | 135 | void nf_conntrack_labels_fini(void) |
Florian Westphal | c539f01 | 2013-01-11 06:30:44 +0000 | [diff] [blame] | 136 | { |
Gao feng | 5f69b8f | 2013-01-21 22:10:31 +0000 | [diff] [blame] | 137 | nf_ct_extend_unregister(&labels_extend); |
Florian Westphal | c539f01 | 2013-01-11 06:30:44 +0000 | [diff] [blame] | 138 | } |