diff options
Diffstat (limited to 'security/selinux/ss/avtab.c')
| -rw-r--r-- | security/selinux/ss/avtab.c | 385 |
1 files changed, 271 insertions, 114 deletions
diff --git a/security/selinux/ss/avtab.c b/security/selinux/ss/avtab.c index f238c034c44..a3dd9faa19c 100644 --- a/security/selinux/ss/avtab.c +++ b/security/selinux/ss/avtab.c @@ -6,40 +6,40 @@ /* Updated: Frank Mayer <mayerf@tresys.com> and Karl MacMillan <kmacmillan@tresys.com> * - * Added conditional policy language extensions + * Added conditional policy language extensions * * Copyright (C) 2003 Tresys Technology, LLC * 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 + * it under the terms of the GNU General Public License as published by * the Free Software Foundation, version 2. + * + * Updated: Yuichi Nakamura <ynakam@hitachisoft.jp> + * Tuned number of hash slots for avtab to reduce memory usage */ #include <linux/kernel.h> #include <linux/slab.h> -#include <linux/vmalloc.h> #include <linux/errno.h> - #include "avtab.h" #include "policydb.h" -#define AVTAB_HASH(keyp) \ -((keyp->target_class + \ - (keyp->target_type << 2) + \ - (keyp->source_type << 9)) & \ - AVTAB_HASH_MASK) +static struct kmem_cache *avtab_node_cachep; -static kmem_cache_t *avtab_node_cachep; +static inline int avtab_hash(struct avtab_key *keyp, u16 mask) +{ + return ((keyp->target_class + (keyp->target_type << 2) + + (keyp->source_type << 9)) & mask); +} static struct avtab_node* avtab_insert_node(struct avtab *h, int hvalue, - struct avtab_node * prev, struct avtab_node * cur, + struct avtab_node *prev, struct avtab_node *cur, struct avtab_key *key, struct avtab_datum *datum) { - struct avtab_node * newnode; - newnode = kmem_cache_alloc(avtab_node_cachep, SLAB_KERNEL); + struct avtab_node *newnode; + newnode = kmem_cache_zalloc(avtab_node_cachep, GFP_KERNEL); if (newnode == NULL) return NULL; - memset(newnode, 0, sizeof(struct avtab_node)); newnode->key = *key; newnode->datum = *datum; if (prev) { @@ -58,18 +58,19 @@ static int avtab_insert(struct avtab *h, struct avtab_key *key, struct avtab_dat { int hvalue; struct avtab_node *prev, *cur, *newnode; + u16 specified = key->specified & ~(AVTAB_ENABLED|AVTAB_ENABLED_OLD); - if (!h) + if (!h || !h->htable) return -EINVAL; - hvalue = AVTAB_HASH(key); + hvalue = avtab_hash(key, h->mask); for (prev = NULL, cur = h->htable[hvalue]; cur; prev = cur, cur = cur->next) { if (key->source_type == cur->key.source_type && key->target_type == cur->key.target_type && key->target_class == cur->key.target_class && - (datum->specified & cur->datum.specified)) + (specified & cur->key.specified)) return -EEXIST; if (key->source_type < cur->key.source_type) break; @@ -83,7 +84,7 @@ static int avtab_insert(struct avtab *h, struct avtab_key *key, struct avtab_dat } newnode = avtab_insert_node(h, hvalue, prev, cur, key, datum); - if(!newnode) + if (!newnode) return -ENOMEM; return 0; @@ -94,21 +95,22 @@ static int avtab_insert(struct avtab *h, struct avtab_key *key, struct avtab_dat * It also returns a pointer to the node inserted. */ struct avtab_node * -avtab_insert_nonunique(struct avtab * h, struct avtab_key * key, struct avtab_datum * datum) +avtab_insert_nonunique(struct avtab *h, struct avtab_key *key, struct avtab_datum *datum) { int hvalue; - struct avtab_node *prev, *cur, *newnode; + struct avtab_node *prev, *cur; + u16 specified = key->specified & ~(AVTAB_ENABLED|AVTAB_ENABLED_OLD); - if (!h) + if (!h || !h->htable) return NULL; - hvalue = AVTAB_HASH(key); + hvalue = avtab_hash(key, h->mask); for (prev = NULL, cur = h->htable[hvalue]; cur; prev = cur, cur = cur->next) { if (key->source_type == cur->key.source_type && key->target_type == cur->key.target_type && key->target_class == cur->key.target_class && - (datum->specified & cur->datum.specified)) + (specified & cur->key.specified)) break; if (key->source_type < cur->key.source_type) break; @@ -120,25 +122,24 @@ avtab_insert_nonunique(struct avtab * h, struct avtab_key * key, struct avtab_da key->target_class < cur->key.target_class) break; } - newnode = avtab_insert_node(h, hvalue, prev, cur, key, datum); - - return newnode; + return avtab_insert_node(h, hvalue, prev, cur, key, datum); } -struct avtab_datum *avtab_search(struct avtab *h, struct avtab_key *key, int specified) +struct avtab_datum *avtab_search(struct avtab *h, struct avtab_key *key) { int hvalue; struct avtab_node *cur; + u16 specified = key->specified & ~(AVTAB_ENABLED|AVTAB_ENABLED_OLD); - if (!h) + if (!h || !h->htable) return NULL; - hvalue = AVTAB_HASH(key); + hvalue = avtab_hash(key, h->mask); for (cur = h->htable[hvalue]; cur; cur = cur->next) { if (key->source_type == cur->key.source_type && key->target_type == cur->key.target_type && key->target_class == cur->key.target_class && - (specified & cur->datum.specified)) + (specified & cur->key.specified)) return &cur->datum; if (key->source_type < cur->key.source_type) @@ -159,20 +160,21 @@ struct avtab_datum *avtab_search(struct avtab *h, struct avtab_key *key, int spe * conjunction with avtab_search_next_node() */ struct avtab_node* -avtab_search_node(struct avtab *h, struct avtab_key *key, int specified) +avtab_search_node(struct avtab *h, struct avtab_key *key) { int hvalue; struct avtab_node *cur; + u16 specified = key->specified & ~(AVTAB_ENABLED|AVTAB_ENABLED_OLD); - if (!h) + if (!h || !h->htable) return NULL; - hvalue = AVTAB_HASH(key); + hvalue = avtab_hash(key, h->mask); for (cur = h->htable[hvalue]; cur; cur = cur->next) { if (key->source_type == cur->key.source_type && key->target_type == cur->key.target_type && key->target_class == cur->key.target_class && - (specified & cur->datum.specified)) + (specified & cur->key.specified)) return cur; if (key->source_type < cur->key.source_type) @@ -196,11 +198,12 @@ avtab_search_node_next(struct avtab_node *node, int specified) if (!node) return NULL; + specified &= ~(AVTAB_ENABLED|AVTAB_ENABLED_OLD); for (cur = node->next; cur; cur = cur->next) { if (node->key.source_type == cur->key.source_type && node->key.target_type == cur->key.target_type && node->key.target_class == cur->key.target_class && - (specified & cur->datum.specified)) + (specified & cur->key.specified)) return cur; if (node->key.source_type < cur->key.source_type) @@ -224,41 +227,72 @@ void avtab_destroy(struct avtab *h) if (!h || !h->htable) return; - for (i = 0; i < AVTAB_SIZE; i++) { + for (i = 0; i < h->nslot; i++) { cur = h->htable[i]; - while (cur != NULL) { + while (cur) { temp = cur; cur = cur->next; kmem_cache_free(avtab_node_cachep, temp); } h->htable[i] = NULL; } - vfree(h->htable); + kfree(h->htable); h->htable = NULL; + h->nslot = 0; + h->mask = 0; } - int avtab_init(struct avtab *h) { - int i; + h->htable = NULL; + h->nel = 0; + return 0; +} + +int avtab_alloc(struct avtab *h, u32 nrules) +{ + u16 mask = 0; + u32 shift = 0; + u32 work = nrules; + u32 nslot = 0; + + if (nrules == 0) + goto avtab_alloc_out; - h->htable = vmalloc(sizeof(*(h->htable)) * AVTAB_SIZE); + while (work) { + work = work >> 1; + shift++; + } + if (shift > 2) + shift = shift - 2; + nslot = 1 << shift; + if (nslot > MAX_AVTAB_HASH_BUCKETS) + nslot = MAX_AVTAB_HASH_BUCKETS; + mask = nslot - 1; + + h->htable = kcalloc(nslot, sizeof(*(h->htable)), GFP_KERNEL); if (!h->htable) return -ENOMEM; - for (i = 0; i < AVTAB_SIZE; i++) - h->htable[i] = NULL; + + avtab_alloc_out: h->nel = 0; + h->nslot = nslot; + h->mask = mask; + printk(KERN_DEBUG "SELinux: %d avtab hash slots, %d rules.\n", + h->nslot, nrules); return 0; } void avtab_hash_eval(struct avtab *h, char *tag) { int i, chain_len, slots_used, max_chain_len; + unsigned long long chain2_len_sum; struct avtab_node *cur; slots_used = 0; max_chain_len = 0; - for (i = 0; i < AVTAB_SIZE; i++) { + chain2_len_sum = 0; + for (i = 0; i < h->nslot; i++) { cur = h->htable[i]; if (cur) { slots_used++; @@ -270,109 +304,190 @@ void avtab_hash_eval(struct avtab *h, char *tag) if (chain_len > max_chain_len) max_chain_len = chain_len; + chain2_len_sum += chain_len * chain_len; } } - printk(KERN_INFO "%s: %d entries and %d/%d buckets used, longest " - "chain length %d\n", tag, h->nel, slots_used, AVTAB_SIZE, - max_chain_len); + printk(KERN_DEBUG "SELinux: %s: %d entries and %d/%d buckets used, " + "longest chain length %d sum of chain length^2 %llu\n", + tag, h->nel, slots_used, h->nslot, max_chain_len, + chain2_len_sum); } -int avtab_read_item(void *fp, struct avtab_datum *avdatum, struct avtab_key *avkey) +static uint16_t spec_order[] = { + AVTAB_ALLOWED, + AVTAB_AUDITDENY, + AVTAB_AUDITALLOW, + AVTAB_TRANSITION, + AVTAB_CHANGE, + AVTAB_MEMBER +}; + +int avtab_read_item(struct avtab *a, void *fp, struct policydb *pol, + int (*insertf)(struct avtab *a, struct avtab_key *k, + struct avtab_datum *d, void *p), + void *p) { - u32 buf[7]; - u32 items, items2; - int rc; + __le16 buf16[4]; + u16 enabled; + __le32 buf32[7]; + u32 items, items2, val, vers = pol->policyvers; + struct avtab_key key; + struct avtab_datum datum; + int i, rc; + unsigned set; + + memset(&key, 0, sizeof(struct avtab_key)); + memset(&datum, 0, sizeof(struct avtab_datum)); + + if (vers < POLICYDB_VERSION_AVTAB) { + rc = next_entry(buf32, fp, sizeof(u32)); + if (rc) { + printk(KERN_ERR "SELinux: avtab: truncated entry\n"); + return rc; + } + items2 = le32_to_cpu(buf32[0]); + if (items2 > ARRAY_SIZE(buf32)) { + printk(KERN_ERR "SELinux: avtab: entry overflow\n"); + return -EINVAL; - memset(avkey, 0, sizeof(struct avtab_key)); - memset(avdatum, 0, sizeof(struct avtab_datum)); + } + rc = next_entry(buf32, fp, sizeof(u32)*items2); + if (rc) { + printk(KERN_ERR "SELinux: avtab: truncated entry\n"); + return rc; + } + items = 0; - rc = next_entry(buf, fp, sizeof(u32)); - if (rc < 0) { - printk(KERN_ERR "security: avtab: truncated entry\n"); - goto bad; - } - items2 = le32_to_cpu(buf[0]); - if (items2 > ARRAY_SIZE(buf)) { - printk(KERN_ERR "security: avtab: entry overflow\n"); - goto bad; + val = le32_to_cpu(buf32[items++]); + key.source_type = (u16)val; + if (key.source_type != val) { + printk(KERN_ERR "SELinux: avtab: truncated source type\n"); + return -EINVAL; + } + val = le32_to_cpu(buf32[items++]); + key.target_type = (u16)val; + if (key.target_type != val) { + printk(KERN_ERR "SELinux: avtab: truncated target type\n"); + return -EINVAL; + } + val = le32_to_cpu(buf32[items++]); + key.target_class = (u16)val; + if (key.target_class != val) { + printk(KERN_ERR "SELinux: avtab: truncated target class\n"); + return -EINVAL; + } + + val = le32_to_cpu(buf32[items++]); + enabled = (val & AVTAB_ENABLED_OLD) ? AVTAB_ENABLED : 0; + + if (!(val & (AVTAB_AV | AVTAB_TYPE))) { + printk(KERN_ERR "SELinux: avtab: null entry\n"); + return -EINVAL; + } + if ((val & AVTAB_AV) && + (val & AVTAB_TYPE)) { + printk(KERN_ERR "SELinux: avtab: entry has both access vectors and types\n"); + return -EINVAL; + } + + for (i = 0; i < ARRAY_SIZE(spec_order); i++) { + if (val & spec_order[i]) { + key.specified = spec_order[i] | enabled; + datum.data = le32_to_cpu(buf32[items++]); + rc = insertf(a, &key, &datum, p); + if (rc) + return rc; + } + } + + if (items != items2) { + printk(KERN_ERR "SELinux: avtab: entry only had %d items, expected %d\n", items2, items); + return -EINVAL; + } + return 0; } - rc = next_entry(buf, fp, sizeof(u32)*items2); - if (rc < 0) { - printk(KERN_ERR "security: avtab: truncated entry\n"); - goto bad; + + rc = next_entry(buf16, fp, sizeof(u16)*4); + if (rc) { + printk(KERN_ERR "SELinux: avtab: truncated entry\n"); + return rc; } + items = 0; - avkey->source_type = le32_to_cpu(buf[items++]); - avkey->target_type = le32_to_cpu(buf[items++]); - avkey->target_class = le32_to_cpu(buf[items++]); - avdatum->specified = le32_to_cpu(buf[items++]); - if (!(avdatum->specified & (AVTAB_AV | AVTAB_TYPE))) { - printk(KERN_ERR "security: avtab: null entry\n"); - goto bad; + key.source_type = le16_to_cpu(buf16[items++]); + key.target_type = le16_to_cpu(buf16[items++]); + key.target_class = le16_to_cpu(buf16[items++]); + key.specified = le16_to_cpu(buf16[items++]); + + if (!policydb_type_isvalid(pol, key.source_type) || + !policydb_type_isvalid(pol, key.target_type) || + !policydb_class_isvalid(pol, key.target_class)) { + printk(KERN_ERR "SELinux: avtab: invalid type or class\n"); + return -EINVAL; } - if ((avdatum->specified & AVTAB_AV) && - (avdatum->specified & AVTAB_TYPE)) { - printk(KERN_ERR "security: avtab: entry has both access vectors and types\n"); - goto bad; + + set = 0; + for (i = 0; i < ARRAY_SIZE(spec_order); i++) { + if (key.specified & spec_order[i]) + set++; } - if (avdatum->specified & AVTAB_AV) { - if (avdatum->specified & AVTAB_ALLOWED) - avtab_allowed(avdatum) = le32_to_cpu(buf[items++]); - if (avdatum->specified & AVTAB_AUDITDENY) - avtab_auditdeny(avdatum) = le32_to_cpu(buf[items++]); - if (avdatum->specified & AVTAB_AUDITALLOW) - avtab_auditallow(avdatum) = le32_to_cpu(buf[items++]); - } else { - if (avdatum->specified & AVTAB_TRANSITION) - avtab_transition(avdatum) = le32_to_cpu(buf[items++]); - if (avdatum->specified & AVTAB_CHANGE) - avtab_change(avdatum) = le32_to_cpu(buf[items++]); - if (avdatum->specified & AVTAB_MEMBER) - avtab_member(avdatum) = le32_to_cpu(buf[items++]); + if (!set || set > 1) { + printk(KERN_ERR "SELinux: avtab: more than one specifier\n"); + return -EINVAL; } - if (items != items2) { - printk(KERN_ERR "security: avtab: entry only had %d items, expected %d\n", - items2, items); - goto bad; + + rc = next_entry(buf32, fp, sizeof(u32)); + if (rc) { + printk(KERN_ERR "SELinux: avtab: truncated entry\n"); + return rc; + } + datum.data = le32_to_cpu(*buf32); + if ((key.specified & AVTAB_TYPE) && + !policydb_type_isvalid(pol, datum.data)) { + printk(KERN_ERR "SELinux: avtab: invalid type\n"); + return -EINVAL; } + return insertf(a, &key, &datum, p); +} - return 0; -bad: - return -1; +static int avtab_insertf(struct avtab *a, struct avtab_key *k, + struct avtab_datum *d, void *p) +{ + return avtab_insert(a, k, d); } -int avtab_read(struct avtab *a, void *fp, u32 config) +int avtab_read(struct avtab *a, void *fp, struct policydb *pol) { int rc; - struct avtab_key avkey; - struct avtab_datum avdatum; - u32 buf[1]; + __le32 buf[1]; u32 nel, i; rc = next_entry(buf, fp, sizeof(u32)); if (rc < 0) { - printk(KERN_ERR "security: avtab: truncated table\n"); + printk(KERN_ERR "SELinux: avtab: truncated table\n"); goto bad; } nel = le32_to_cpu(buf[0]); if (!nel) { - printk(KERN_ERR "security: avtab: table is empty\n"); + printk(KERN_ERR "SELinux: avtab: table is empty\n"); rc = -EINVAL; goto bad; } + + rc = avtab_alloc(a, nel); + if (rc) + goto bad; + for (i = 0; i < nel; i++) { - if (avtab_read_item(fp, &avdatum, &avkey)) { - rc = -EINVAL; - goto bad; - } - rc = avtab_insert(a, &avkey, &avdatum); + rc = avtab_read_item(a, fp, pol, avtab_insertf, NULL); if (rc) { if (rc == -ENOMEM) - printk(KERN_ERR "security: avtab: out of memory\n"); - if (rc == -EEXIST) - printk(KERN_ERR "security: avtab: duplicate entry\n"); + printk(KERN_ERR "SELinux: avtab: out of memory\n"); + else if (rc == -EEXIST) + printk(KERN_ERR "SELinux: avtab: duplicate entry\n"); + goto bad; } } @@ -386,14 +501,56 @@ bad: goto out; } +int avtab_write_item(struct policydb *p, struct avtab_node *cur, void *fp) +{ + __le16 buf16[4]; + __le32 buf32[1]; + int rc; + + buf16[0] = cpu_to_le16(cur->key.source_type); + buf16[1] = cpu_to_le16(cur->key.target_type); + buf16[2] = cpu_to_le16(cur->key.target_class); + buf16[3] = cpu_to_le16(cur->key.specified); + rc = put_entry(buf16, sizeof(u16), 4, fp); + if (rc) + return rc; + buf32[0] = cpu_to_le32(cur->datum.data); + rc = put_entry(buf32, sizeof(u32), 1, fp); + if (rc) + return rc; + return 0; +} + +int avtab_write(struct policydb *p, struct avtab *a, void *fp) +{ + unsigned int i; + int rc = 0; + struct avtab_node *cur; + __le32 buf[1]; + + buf[0] = cpu_to_le32(a->nel); + rc = put_entry(buf, sizeof(u32), 1, fp); + if (rc) + return rc; + + for (i = 0; i < a->nslot; i++) { + for (cur = a->htable[i]; cur; cur = cur->next) { + rc = avtab_write_item(p, cur, fp); + if (rc) + return rc; + } + } + + return rc; +} void avtab_cache_init(void) { avtab_node_cachep = kmem_cache_create("avtab_node", sizeof(struct avtab_node), - 0, SLAB_PANIC, NULL, NULL); + 0, SLAB_PANIC, NULL); } void avtab_cache_destroy(void) { - kmem_cache_destroy (avtab_node_cachep); + kmem_cache_destroy(avtab_node_cachep); } |
