1 files changed, 167 insertions, 0 deletions

diff --git a/security/selinux/ss/hashtab.c b/security/selinux/ss/hashtab.c
new file mode 100644
index 000000000000..26661fcc00ce
--- /dev/null
+++ b/security/selinux/ss/hashtab.c
@@ -0,0 +1,167 @@
+/*
+ * Implementation of the hash table type.
+ *
+ * Author : Stephen Smalley, <sds@epoch.ncsc.mil>
+ */
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/errno.h>
+#include "hashtab.h"
+
+struct hashtab *hashtab_create(u32 (*hash_value)(struct hashtab *h, void *key),
+                               int (*keycmp)(struct hashtab *h, void *key1, void *key2),
+                               u32 size)
+{
+        struct hashtab *p;
+        u32 i;
+
+        p = kmalloc(sizeof(*p), GFP_KERNEL);
+        if (p == NULL)
+                return p;
+
+        memset(p, 0, sizeof(*p));
+        p->size = size;
+        p->nel = 0;
+        p->hash_value = hash_value;
+        p->keycmp = keycmp;
+        p->htable = kmalloc(sizeof(*(p->htable)) * size, GFP_KERNEL);
+        if (p->htable == NULL) {
+                kfree(p);
+                return NULL;
+        }
+
+        for (i = 0; i < size; i++)
+                p->htable[i] = NULL;
+
+        return p;
+}
+
+int hashtab_insert(struct hashtab *h, void *key, void *datum)
+{
+        u32 hvalue;
+        struct hashtab_node *prev, *cur, *newnode;
+
+        if (!h || h->nel == HASHTAB_MAX_NODES)
+                return -EINVAL;
+
+        hvalue = h->hash_value(h, key);
+        prev = NULL;
+        cur = h->htable[hvalue];
+        while (cur && h->keycmp(h, key, cur->key) > 0) {
+                prev = cur;
+                cur = cur->next;
+        }
+
+        if (cur && (h->keycmp(h, key, cur->key) == 0))
+                return -EEXIST;
+
+        newnode = kmalloc(sizeof(*newnode), GFP_KERNEL);
+        if (newnode == NULL)
+                return -ENOMEM;
+        memset(newnode, 0, sizeof(*newnode));
+        newnode->key = key;
+        newnode->datum = datum;
+        if (prev) {
+                newnode->next = prev->next;
+                prev->next = newnode;
+        } else {
+                newnode->next = h->htable[hvalue];
+                h->htable[hvalue] = newnode;
+        }
+
+        h->nel++;
+        return 0;
+}
+
+void *hashtab_search(struct hashtab *h, void *key)
+{
+        u32 hvalue;
+        struct hashtab_node *cur;
+
+        if (!h)
+                return NULL;
+
+        hvalue = h->hash_value(h, key);
+        cur = h->htable[hvalue];
+        while (cur != NULL && h->keycmp(h, key, cur->key) > 0)
+                cur = cur->next;
+
+        if (cur == NULL || (h->keycmp(h, key, cur->key) != 0))
+                return NULL;
+
+        return cur->datum;
+}
+
+void hashtab_destroy(struct hashtab *h)
+{
+        u32 i;
+        struct hashtab_node *cur, *temp;
+
+        if (!h)
+                return;
+
+        for (i = 0; i < h->size; i++) {
+                cur = h->htable[i];
+                while (cur != NULL) {
+                        temp = cur;
+                        cur = cur->next;
+                        kfree(temp);
+                }
+                h->htable[i] = NULL;
+        }
+
+        kfree(h->htable);
+        h->htable = NULL;
+
+        kfree(h);
+}
+
+int hashtab_map(struct hashtab *h,
+                int (*apply)(void *k, void *d, void *args),
+                void *args)
+{
+        u32 i;
+        int ret;
+        struct hashtab_node *cur;
+
+        if (!h)
+                return 0;
+
+        for (i = 0; i < h->size; i++) {
+                cur = h->htable[i];
+                while (cur != NULL) {
+                        ret = apply(cur->key, cur->datum, args);
+                        if (ret)
+                                return ret;
+                        cur = cur->next;
+                }
+        }
+        return 0;
+}
+
+
+void hashtab_stat(struct hashtab *h, struct hashtab_info *info)
+{
+        u32 i, chain_len, slots_used, max_chain_len;
+        struct hashtab_node *cur;
+
+        slots_used = 0;
+        max_chain_len = 0;
+        for (slots_used = max_chain_len = i = 0; i < h->size; i++) {
+                cur = h->htable[i];
+                if (cur) {
+                        slots_used++;
+                        chain_len = 0;
+                        while (cur) {
+                                chain_len++;
+                                cur = cur->next;
+                        }
+
+                        if (chain_len > max_chain_len)
+                                max_chain_len = chain_len;
+                }
+        }
+
+        info->slots_used = slots_used;
+        info->max_chain_len = max_chain_len;
+}