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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-19 05:31:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-19 05:31:45 +0000 |
commit | 74aa0bc6779af38018a03fd2cf4419fe85917904 (patch) | |
tree | 9cb0681aac9a94a49c153d5823e7a55d1513d91f /src/util/mmap_cache.h | |
parent | Initial commit. (diff) | |
download | sssd-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.h | 161 |
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_ */ |