summaryrefslogtreecommitdiffstats
path: root/src/util/mmap_cache.h
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 05:31:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 05:31:45 +0000
commit74aa0bc6779af38018a03fd2cf4419fe85917904 (patch)
tree9cb0681aac9a94a49c153d5823e7a55d1513d91f /src/util/mmap_cache.h
parentInitial commit. (diff)
downloadsssd-74aa0bc6779af38018a03fd2cf4419fe85917904.tar.xz
sssd-74aa0bc6779af38018a03fd2cf4419fe85917904.zip
Adding upstream version 2.9.4.upstream/2.9.4
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/util/mmap_cache.h')
-rw-r--r--src/util/mmap_cache.h161
1 files changed, 161 insertions, 0 deletions
diff --git a/src/util/mmap_cache.h b/src/util/mmap_cache.h
new file mode 100644
index 0000000..3f2b6c2
--- /dev/null
+++ b/src/util/mmap_cache.h
@@ -0,0 +1,161 @@
+/*
+ SSSD
+
+ Mmap Cache Common header
+
+ Copyright (C) Simo Sorce <ssorce@redhat.com> 2011
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#ifndef _MMAP_CACHE_H_
+#define _MMAP_CACHE_H_
+
+#include "shared/murmurhash3.h"
+
+
+/* NOTE: all the code here assumes that writing a uint32_t nto mmapped
+ * memory is an atomic operation and can't be split in multiple
+ * non-atomic operations */
+typedef uint32_t rel_ptr_t;
+
+/* align macros */
+#define MC_8 sizeof(uint8_t)
+#define MC_32 sizeof(uint32_t)
+#define MC_64 sizeof(uint64_t)
+#define MC_ALIGN32(size) ( ((size) + MC_32 -1) & (~(MC_32 -1)) )
+#define MC_ALIGN64(size) ( ((size) + MC_64 -1) & (~(MC_64 -1)) )
+#define MC_HEADER_SIZE MC_ALIGN64(sizeof(struct sss_mc_header))
+
+#define MC_HT_SIZE(elems) ( (elems) * MC_32 )
+#define MC_HT_ELEMS(size) ( (size) / MC_32 )
+
+#define MC_PTR_ADD(ptr, bytes) (void *)((uint8_t *)(ptr) + (bytes))
+#define MC_PTR_DIFF(ptr, base) ((uint8_t *)(ptr) - (uint8_t *)(base))
+
+#define MC_INVALID_VAL64 ((uint64_t)-1)
+#define MC_INVALID_VAL32 ((uint32_t)-1)
+#define MC_INVALID_VAL8 ((uint8_t)-1)
+#define MC_INVALID_VAL MC_INVALID_VAL32
+
+/*
+ * 40 seem a good compromise for slot size
+ * 4 blocks are enough for the average passwd entry of 42 bytes
+ * passwd records have 84 bytes of overhead, 160 - 82 = 78 bytes
+ * 3 blocks can contain a very minimal entry, 120 - 82 = 38 bytes
+ *
+ * 3 blocks are enough for groups w/o users (private user groups)
+ * group records have 68 bytes of overhead, 120 - 66 = 54 bytes
+ */
+#define MC_SLOT_SIZE 40
+#define MC_SIZE_TO_SLOTS(len) (((len) + (MC_SLOT_SIZE - 1)) / MC_SLOT_SIZE)
+#define MC_PTR_TO_SLOT(base, ptr) (MC_PTR_DIFF(ptr, base) / MC_SLOT_SIZE)
+#define MC_SLOT_TO_PTR(base, slot, type) \
+ (type *)((base) + ((slot) * MC_SLOT_SIZE))
+
+#define MC_SLOT_WITHIN_BOUNDS(slot, dt_size) \
+ ((slot) < ((dt_size) / MC_SLOT_SIZE))
+
+#define MC_VALID_BARRIER(val) (((val) & 0xff000000) == 0xf0000000)
+
+#define MC_CHECK_RECORD_LENGTH(mc_ctx, rec) \
+ ((rec)->len >= MC_HEADER_SIZE && (rec)->len != MC_INVALID_VAL32 \
+ && ((rec)->len <= ((mc_ctx)->dt_size \
+ - MC_PTR_DIFF(rec, (mc_ctx)->data_table))))
+
+
+#define SSS_MC_MAJOR_VNO 1
+#define SSS_MC_MINOR_VNO 1
+
+#define SSS_MC_HEADER_UNINIT 0 /* after ftruncate or before reset */
+#define SSS_MC_HEADER_ALIVE 1 /* current and in use */
+#define SSS_MC_HEADER_RECYCLED 2 /* file was recycled, reopen asap */
+
+#pragma pack(1)
+struct sss_mc_header {
+ uint32_t b1; /* barrier 1 */
+ uint32_t major_vno; /* major version number */
+ uint32_t minor_vno; /* minor version number */
+ uint32_t status; /* database status */
+ uint32_t seed; /* random seed used to avoid collision attacks */
+ uint32_t dt_size; /* data table size */
+ uint32_t ft_size; /* free table size */
+ uint32_t ht_size; /* hash table size */
+ rel_ptr_t data_table; /* data table pointer relative to mmap base */
+ rel_ptr_t free_table; /* free table pointer relative to mmap base */
+ rel_ptr_t hash_table; /* hash table pointer relative to mmap base */
+ rel_ptr_t reserved; /* reserved for future changes */
+ uint32_t b2; /* barrier 2 */
+};
+
+struct sss_mc_rec {
+ uint32_t b1; /* barrier 1 */
+ uint32_t len; /* total record length including record data */
+ uint64_t expire; /* record expiration time (cast to time_t) */
+ rel_ptr_t next1; /* ptr of next record rel to data_table */
+ /* next1 is related to hash1 */
+ rel_ptr_t next2; /* ptr of next record rel to data_table */
+ /* next2 is related to hash2 */
+ uint32_t hash1; /* val of first hash (usually name of record) */
+ uint32_t hash2; /* val of second hash (usually id of record) */
+ uint32_t padding; /* padding & reserved for future changes */
+ uint32_t b2; /* barrier 2 - 32 bytes mark, fits a slot */
+ char data[0];
+};
+
+struct sss_mc_pwd_data {
+ rel_ptr_t name; /* ptr to name string, rel. to struct base addr */
+ uint32_t uid;
+ uint32_t gid;
+ uint32_t strs_len; /* length of strs */
+ char strs[0]; /* concatenation of all passwd strings, each
+ * string is zero terminated ordered as follows:
+ * name, passwd, gecos, dir, shell */
+};
+
+struct sss_mc_grp_data {
+ rel_ptr_t name; /* ptr to name string, rel. to struct base addr */
+ uint32_t gid;
+ uint32_t members; /* number of members in strs */
+ uint32_t strs_len; /* length of strs */
+ char strs[0]; /* concatenation of all group strings, each
+ * string is zero terminated ordered as follows:
+ * name, passwd, member1, member2, ... */
+};
+
+struct sss_mc_initgr_data {
+ rel_ptr_t unique_name; /* ptr to unique name string, rel. to struct base addr */
+ rel_ptr_t name; /* ptr to raw name string, rel. to struct base addr */
+ rel_ptr_t strs; /* ptr to concatenation of all strings */
+ uint32_t strs_len; /* length of strs */
+ uint32_t data_len; /* all initgroups data len */
+ uint32_t num_groups; /* number of groups */
+ uint32_t gids[0]; /* array of all groups
+ * string with name and unique_name is stored
+ * after gids */
+};
+
+struct sss_mc_sid_data {
+ rel_ptr_t name; /* ptr to SID string, rel. to struct base addr */
+ uint32_t type; /* enum sss_id_type */
+ uint32_t id; /* gid or uid */
+ uint32_t populated_by; /* 0 - by_id(), 1 - by_uid/gid() lookup */
+ uint32_t sid_len; /* length of sid */
+ char sid[0];
+};
+
+#pragma pack()
+
+
+#endif /* _MMAP_CACHE_H_ */