diff options
| author | Hongru Zhang <zhanghongru@xiaomi.com> | 2025-10-23 19:29:54 +0800 |
|---|---|---|
| committer | Paul Moore <paul@paul-moore.com> | 2025-10-23 18:24:30 -0400 |
| commit | 929126ef4a0e2723622eb3ba11017ca5fecd37d3 (patch) | |
| tree | 5f96b1cd6de5206e703403f8844b089a7213c006 | |
| parent | 641e0217586193bbd6dbc16ae73d0c9ecda535f1 (diff) | |
selinux: Move avtab_hash() to a shared location for future reuse
This is a preparation patch, no functional change.
Signed-off-by: Hongru Zhang <zhanghongru@xiaomi.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
| -rw-r--r-- | security/selinux/include/hash.h | 46 | ||||
| -rw-r--r-- | security/selinux/ss/avtab.c | 41 |
2 files changed, 47 insertions, 40 deletions
diff --git a/security/selinux/include/hash.h b/security/selinux/include/hash.h new file mode 100644 index 000000000000..5b429a873eb6 --- /dev/null +++ b/security/selinux/include/hash.h @@ -0,0 +1,46 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ + +#ifndef _SELINUX_HASH_H_ +#define _SELINUX_HASH_H_ + +/* Based on MurmurHash3, written by Austin Appleby and placed in the + * public domain. + */ +static inline u32 avtab_hash(const struct avtab_key *keyp, u32 mask) +{ + static const u32 c1 = 0xcc9e2d51; + static const u32 c2 = 0x1b873593; + static const u32 r1 = 15; + static const u32 r2 = 13; + static const u32 m = 5; + static const u32 n = 0xe6546b64; + + u32 hash = 0; + +#define mix(input) \ + do { \ + u32 v = input; \ + v *= c1; \ + v = (v << r1) | (v >> (32 - r1)); \ + v *= c2; \ + hash ^= v; \ + hash = (hash << r2) | (hash >> (32 - r2)); \ + hash = hash * m + n; \ + } while (0) + + mix(keyp->target_class); + mix(keyp->target_type); + mix(keyp->source_type); + +#undef mix + + hash ^= hash >> 16; + hash *= 0x85ebca6b; + hash ^= hash >> 13; + hash *= 0xc2b2ae35; + hash ^= hash >> 16; + + return hash & mask; +} + +#endif /* _SELINUX_HASH_H_ */ diff --git a/security/selinux/ss/avtab.c b/security/selinux/ss/avtab.c index c2c31521cace..15e89d9b5d72 100644 --- a/security/selinux/ss/avtab.c +++ b/security/selinux/ss/avtab.c @@ -20,50 +20,11 @@ #include <linux/errno.h> #include "avtab.h" #include "policydb.h" +#include "hash.h" static struct kmem_cache *avtab_node_cachep __ro_after_init; static struct kmem_cache *avtab_xperms_cachep __ro_after_init; -/* Based on MurmurHash3, written by Austin Appleby and placed in the - * public domain. - */ -static inline u32 avtab_hash(const struct avtab_key *keyp, u32 mask) -{ - static const u32 c1 = 0xcc9e2d51; - static const u32 c2 = 0x1b873593; - static const u32 r1 = 15; - static const u32 r2 = 13; - static const u32 m = 5; - static const u32 n = 0xe6546b64; - - u32 hash = 0; - -#define mix(input) \ - do { \ - u32 v = input; \ - v *= c1; \ - v = (v << r1) | (v >> (32 - r1)); \ - v *= c2; \ - hash ^= v; \ - hash = (hash << r2) | (hash >> (32 - r2)); \ - hash = hash * m + n; \ - } while (0) - - mix(keyp->target_class); - mix(keyp->target_type); - mix(keyp->source_type); - -#undef mix - - hash ^= hash >> 16; - hash *= 0x85ebca6b; - hash ^= hash >> 13; - hash *= 0xc2b2ae35; - hash ^= hash >> 16; - - return hash & mask; -} - static struct avtab_node *avtab_insert_node(struct avtab *h, struct avtab_node **dst, const struct avtab_key *key, |