1 files changed, 201 insertions, 0 deletions

diff --git a/net/netlabel/netlabel_kapi.c b/net/netlabel/netlabel_kapi.c
index b35ebf94918c..e03a3282c551 100644
--- a/net/netlabel/netlabel_kapi.c
+++ b/net/netlabel/netlabel_kapi.c
@@ -40,6 +40,207 @@
 #include "netlabel_user.h"
 
 /*
+ * Security Attribute Functions
+ */
+
+/**
+ * netlbl_secattr_catmap_walk - Walk a LSM secattr catmap looking for a bit
+ * @catmap: the category bitmap
+ * @offset: the offset to start searching at, in bits
+ *
+ * Description:
+ * This function walks a LSM secattr category bitmap starting at @offset and
+ * returns the spot of the first set bit or -ENOENT if no bits are set.
+ *
+ */
+int netlbl_secattr_catmap_walk(struct netlbl_lsm_secattr_catmap *catmap,
+                               u32 offset)
+{
+        struct netlbl_lsm_secattr_catmap *iter = catmap;
+        u32 node_idx;
+        u32 node_bit;
+        NETLBL_CATMAP_MAPTYPE bitmap;
+
+        if (offset > iter->startbit) {
+                while (offset >= (iter->startbit + NETLBL_CATMAP_SIZE)) {
+                        iter = iter->next;
+                        if (iter == NULL)
+                                return -ENOENT;
+                }
+                node_idx = (offset - iter->startbit) / NETLBL_CATMAP_MAPSIZE;
+                node_bit = offset - iter->startbit -
+                           (NETLBL_CATMAP_MAPSIZE * node_idx);
+        } else {
+                node_idx = 0;
+                node_bit = 0;
+        }
+        bitmap = iter->bitmap[node_idx] >> node_bit;
+
+        for (;;) {
+                if (bitmap != 0) {
+                        while ((bitmap & NETLBL_CATMAP_BIT) == 0) {
+                                bitmap >>= 1;
+                                node_bit++;
+                        }
+                        return iter->startbit +
+                                (NETLBL_CATMAP_MAPSIZE * node_idx) + node_bit;
+                }
+                if (++node_idx >= NETLBL_CATMAP_MAPCNT) {
+                        if (iter->next != NULL) {
+                                iter = iter->next;
+                                node_idx = 0;
+                        } else
+                                return -ENOENT;
+                }
+                bitmap = iter->bitmap[node_idx];
+                node_bit = 0;
+        }
+
+        return -ENOENT;
+}
+
+/**
+ * netlbl_secattr_catmap_walk_rng - Find the end of a string of set bits
+ * @catmap: the category bitmap
+ * @offset: the offset to start searching at, in bits
+ *
+ * Description:
+ * This function walks a LSM secattr category bitmap starting at @offset and
+ * returns the spot of the first cleared bit or -ENOENT if the offset is past
+ * the end of the bitmap.
+ *
+ */
+int netlbl_secattr_catmap_walk_rng(struct netlbl_lsm_secattr_catmap *catmap,
+                                   u32 offset)
+{
+        struct netlbl_lsm_secattr_catmap *iter = catmap;
+        u32 node_idx;
+        u32 node_bit;
+        NETLBL_CATMAP_MAPTYPE bitmask;
+        NETLBL_CATMAP_MAPTYPE bitmap;
+
+        if (offset > iter->startbit) {
+                while (offset >= (iter->startbit + NETLBL_CATMAP_SIZE)) {
+                        iter = iter->next;
+                        if (iter == NULL)
+                                return -ENOENT;
+                }
+                node_idx = (offset - iter->startbit) / NETLBL_CATMAP_MAPSIZE;
+                node_bit = offset - iter->startbit -
+                           (NETLBL_CATMAP_MAPSIZE * node_idx);
+        } else {
+                node_idx = 0;
+                node_bit = 0;
+        }
+        bitmask = NETLBL_CATMAP_BIT << node_bit;
+
+        for (;;) {
+                bitmap = iter->bitmap[node_idx];
+                while (bitmask != 0 && (bitmap & bitmask) != 0) {
+                        bitmask <<= 1;
+                        node_bit++;
+                }
+
+                if (bitmask != 0)
+                        return iter->startbit +
+                                (NETLBL_CATMAP_MAPSIZE * node_idx) +
+                                node_bit - 1;
+                else if (++node_idx >= NETLBL_CATMAP_MAPCNT) {
+                        if (iter->next == NULL)
+                                return iter->startbit + NETLBL_CATMAP_SIZE - 1;
+                        iter = iter->next;
+                        node_idx = 0;
+                }
+                bitmask = NETLBL_CATMAP_BIT;
+                node_bit = 0;
+        }
+
+        return -ENOENT;
+}
+
+/**
+ * netlbl_secattr_catmap_setbit - Set a bit in a LSM secattr catmap
+ * @catmap: the category bitmap
+ * @bit: the bit to set
+ * @flags: memory allocation flags
+ *
+ * Description:
+ * Set the bit specified by @bit in @catmap.  Returns zero on success,
+ * negative values on failure.
+ *
+ */
+int netlbl_secattr_catmap_setbit(struct netlbl_lsm_secattr_catmap *catmap,
+                                 u32 bit,
+                                 gfp_t flags)
+{
+        struct netlbl_lsm_secattr_catmap *iter = catmap;
+        u32 node_bit;
+        u32 node_idx;
+
+        while (iter->next != NULL &&
+               bit >= (iter->startbit + NETLBL_CATMAP_SIZE))
+                iter = iter->next;
+        if (bit >= (iter->startbit + NETLBL_CATMAP_SIZE)) {
+                iter->next = netlbl_secattr_catmap_alloc(flags);
+                if (iter->next == NULL)
+                        return -ENOMEM;
+                iter = iter->next;
+                iter->startbit = bit & ~(NETLBL_CATMAP_SIZE - 1);
+        }
+
+        /* gcc always rounds to zero when doing integer division */
+        node_idx = (bit - iter->startbit) / NETLBL_CATMAP_MAPSIZE;
+        node_bit = bit - iter->startbit - (NETLBL_CATMAP_MAPSIZE * node_idx);
+        iter->bitmap[node_idx] |= NETLBL_CATMAP_BIT << node_bit;
+
+        return 0;
+}
+
+/**
+ * netlbl_secattr_catmap_setrng - Set a range of bits in a LSM secattr catmap
+ * @catmap: the category bitmap
+ * @start: the starting bit
+ * @end: the last bit in the string
+ * @flags: memory allocation flags
+ *
+ * Description:
+ * Set a range of bits, starting at @start and ending with @end.  Returns zero
+ * on success, negative values on failure.
+ *
+ */
+int netlbl_secattr_catmap_setrng(struct netlbl_lsm_secattr_catmap *catmap,
+                                 u32 start,
+                                 u32 end,
+                                 gfp_t flags)
+{
+        int ret_val = 0;
+        struct netlbl_lsm_secattr_catmap *iter = catmap;
+        u32 iter_max_spot;
+        u32 spot;
+
+        /* XXX - This could probably be made a bit faster by combining writes
+         * to the catmap instead of setting a single bit each time, but for
+         * right now skipping to the start of the range in the catmap should
+         * be a nice improvement over calling the individual setbit function
+         * repeatedly from a loop. */
+
+        while (iter->next != NULL &&
+               start >= (iter->startbit + NETLBL_CATMAP_SIZE))
+                iter = iter->next;
+        iter_max_spot = iter->startbit + NETLBL_CATMAP_SIZE;
+
+        for (spot = start; spot <= end && ret_val == 0; spot++) {
+                if (spot >= iter_max_spot && iter->next != NULL) {
+                        iter = iter->next;
+                        iter_max_spot = iter->startbit + NETLBL_CATMAP_SIZE;
+                }
+                ret_val = netlbl_secattr_catmap_setbit(iter, spot, GFP_ATOMIC);
+        }
+
+        return ret_val;
+}
+
+/*
  * LSM Functions
  */