URL https://opencores.org/ocsvn/test_project/test_project/trunk

Subversion Repositories test_project

[/] [test_project/] [trunk/] [linux_sd_driver/] [security/] [selinux/] [ss/] [ebitmap.c] - Blame information for rev 62

Details | Compare with Previous | View Log


/*
 * Implementation of the extensible bitmap type.
 *
 * Author : Stephen Smalley, <sds@epoch.ncsc.mil>
 */
/*
 * Updated: Hewlett-Packard <paul.moore@hp.com>
 *
 *      Added support to import/export the NetLabel category bitmap
 *
 * (c) Copyright Hewlett-Packard Development Company, L.P., 2006
 */
/*
 * Updated: KaiGai Kohei <kaigai@ak.jp.nec.com>
 *      Applied standard bit operations to improve bitmap scanning.
 */
 
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/errno.h>
#include <net/netlabel.h>
#include "ebitmap.h"
#include "policydb.h"
 
int ebitmap_cmp(struct ebitmap *e1, struct ebitmap *e2)
{
        struct ebitmap_node *n1, *n2;
 
        if (e1->highbit != e2->highbit)
                return 0;
 
        n1 = e1->node;
        n2 = e2->node;
        while (n1 && n2 &&
               (n1->startbit == n2->startbit) &&
               !memcmp(n1->maps, n2->maps, EBITMAP_SIZE / 8)) {
                n1 = n1->next;
                n2 = n2->next;
        }
 
        if (n1 || n2)
                return 0;
 
        return 1;
}
 
int ebitmap_cpy(struct ebitmap *dst, struct ebitmap *src)
{
        struct ebitmap_node *n, *new, *prev;
 
        ebitmap_init(dst);
        n = src->node;
        prev = NULL;
        while (n) {
                new = kzalloc(sizeof(*new), GFP_ATOMIC);
                if (!new) {
                        ebitmap_destroy(dst);
                        return -ENOMEM;
                }
                new->startbit = n->startbit;
                memcpy(new->maps, n->maps, EBITMAP_SIZE / 8);
                new->next = NULL;
                if (prev)
                        prev->next = new;
                else
                        dst->node = new;
                prev = new;
                n = n->next;
        }
 
        dst->highbit = src->highbit;
        return 0;
}
 
#ifdef CONFIG_NETLABEL
/**
 * ebitmap_netlbl_export - Export an ebitmap into a NetLabel category bitmap
 * @ebmap: the ebitmap to export
 * @catmap: the NetLabel category bitmap
 *
 * Description:
 * Export a SELinux extensibile bitmap into a NetLabel category bitmap.
 * Returns zero on success, negative values on error.
 *
 */
int ebitmap_netlbl_export(struct ebitmap *ebmap,
                          struct netlbl_lsm_secattr_catmap **catmap)
{
        struct ebitmap_node *e_iter = ebmap->node;
        struct netlbl_lsm_secattr_catmap *c_iter;
        u32 cmap_idx, cmap_sft;
        int i;
 
        /* NetLabel's NETLBL_CATMAP_MAPTYPE is defined as an array of u64,
         * however, it is not always compatible with an array of unsigned long
         * in ebitmap_node.
         * In addition, you should pay attention the following implementation
         * assumes unsigned long has a width equal with or less than 64-bit.
         */
 
        if (e_iter == NULL) {
                *catmap = NULL;
                return 0;
        }
 
        c_iter = netlbl_secattr_catmap_alloc(GFP_ATOMIC);
        if (c_iter == NULL)
                return -ENOMEM;
        *catmap = c_iter;
        c_iter->startbit = e_iter->startbit & ~(NETLBL_CATMAP_SIZE - 1);
 
        while (e_iter != NULL) {
                for (i = 0; i < EBITMAP_UNIT_NUMS; i++) {
                        unsigned int delta, e_startbit, c_endbit;
 
                        e_startbit = e_iter->startbit + i * EBITMAP_UNIT_SIZE;
                        c_endbit = c_iter->startbit + NETLBL_CATMAP_SIZE;
                        if (e_startbit >= c_endbit) {
                                c_iter->next
                                  = netlbl_secattr_catmap_alloc(GFP_ATOMIC);
                                if (c_iter->next == NULL)
                                        goto netlbl_export_failure;
                                c_iter = c_iter->next;
                                c_iter->startbit
                                  = e_startbit & ~(NETLBL_CATMAP_SIZE - 1);
                        }
                        delta = e_startbit - c_iter->startbit;
                        cmap_idx = delta / NETLBL_CATMAP_MAPSIZE;
                        cmap_sft = delta % NETLBL_CATMAP_MAPSIZE;
                        c_iter->bitmap[cmap_idx]
                                |= e_iter->maps[cmap_idx] << cmap_sft;
                }
                e_iter = e_iter->next;
        }
 
        return 0;
 
netlbl_export_failure:
        netlbl_secattr_catmap_free(*catmap);
        return -ENOMEM;
}
 
/**
 * ebitmap_netlbl_import - Import a NetLabel category bitmap into an ebitmap
 * @ebmap: the ebitmap to import
 * @catmap: the NetLabel category bitmap
 *
 * Description:
 * Import a NetLabel category bitmap into a SELinux extensibile bitmap.
 * Returns zero on success, negative values on error.
 *
 */
int ebitmap_netlbl_import(struct ebitmap *ebmap,
                          struct netlbl_lsm_secattr_catmap *catmap)
{
        struct ebitmap_node *e_iter = NULL;
        struct ebitmap_node *emap_prev = NULL;
        struct netlbl_lsm_secattr_catmap *c_iter = catmap;
        u32 c_idx, c_pos, e_idx, e_sft;
 
        /* NetLabel's NETLBL_CATMAP_MAPTYPE is defined as an array of u64,
         * however, it is not always compatible with an array of unsigned long
         * in ebitmap_node.
         * In addition, you should pay attention the following implementation
         * assumes unsigned long has a width equal with or less than 64-bit.
         */
 
        do {
                for (c_idx = 0; c_idx < NETLBL_CATMAP_MAPCNT; c_idx++) {
                        unsigned int delta;
                        u64 map = c_iter->bitmap[c_idx];
 
                        if (!map)
                                continue;
 
                        c_pos = c_iter->startbit
                                + c_idx * NETLBL_CATMAP_MAPSIZE;
                        if (!e_iter
                            || c_pos >= e_iter->startbit + EBITMAP_SIZE) {
                                e_iter = kzalloc(sizeof(*e_iter), GFP_ATOMIC);
                                if (!e_iter)
                                        goto netlbl_import_failure;
                                e_iter->startbit
                                        = c_pos - (c_pos % EBITMAP_SIZE);
                                if (emap_prev == NULL)
                                        ebmap->node = e_iter;
                                else
                                        emap_prev->next = e_iter;
                                emap_prev = e_iter;
                        }
                        delta = c_pos - e_iter->startbit;
                        e_idx = delta / EBITMAP_UNIT_SIZE;
                        e_sft = delta % EBITMAP_UNIT_SIZE;
                        while (map) {
                                e_iter->maps[e_idx++] |= map & (-1UL);
                                map = EBITMAP_SHIFT_UNIT_SIZE(map);
                        }
                }
                c_iter = c_iter->next;
        } while (c_iter != NULL);
        if (e_iter != NULL)
                ebmap->highbit = e_iter->startbit + EBITMAP_SIZE;
        else
                ebitmap_destroy(ebmap);
 
        return 0;
 
netlbl_import_failure:
        ebitmap_destroy(ebmap);
        return -ENOMEM;
}
#endif /* CONFIG_NETLABEL */
 
int ebitmap_contains(struct ebitmap *e1, struct ebitmap *e2)
{
        struct ebitmap_node *n1, *n2;
        int i;
 
        if (e1->highbit < e2->highbit)
                return 0;
 
        n1 = e1->node;
        n2 = e2->node;
        while (n1 && n2 && (n1->startbit <= n2->startbit)) {
                if (n1->startbit < n2->startbit) {
                        n1 = n1->next;
                        continue;
                }
                for (i = 0; i < EBITMAP_UNIT_NUMS; i++) {
                        if ((n1->maps[i] & n2->maps[i]) != n2->maps[i])
                                return 0;
                }
 
                n1 = n1->next;
                n2 = n2->next;
        }
 
        if (n2)
                return 0;
 
        return 1;
}
 
int ebitmap_get_bit(struct ebitmap *e, unsigned long bit)
{
        struct ebitmap_node *n;
 
        if (e->highbit < bit)
                return 0;
 
        n = e->node;
        while (n && (n->startbit <= bit)) {
                if ((n->startbit + EBITMAP_SIZE) > bit)
                        return ebitmap_node_get_bit(n, bit);
                n = n->next;
        }
 
        return 0;
}
 
int ebitmap_set_bit(struct ebitmap *e, unsigned long bit, int value)
{
        struct ebitmap_node *n, *prev, *new;
 
        prev = NULL;
        n = e->node;
        while (n && n->startbit <= bit) {
                if ((n->startbit + EBITMAP_SIZE) > bit) {
                        if (value) {
                                ebitmap_node_set_bit(n, bit);
                        } else {
                                unsigned int s;
 
                                ebitmap_node_clr_bit(n, bit);
 
                                s = find_first_bit(n->maps, EBITMAP_SIZE);
                                if (s < EBITMAP_SIZE)
                                        return 0;
 
                                /* drop this node from the bitmap */
                                if (!n->next) {
                                        /*
                                         * this was the highest map
                                         * within the bitmap
                                         */
                                        if (prev)
                                                e->highbit = prev->startbit
                                                             + EBITMAP_SIZE;
                                        else
                                                e->highbit = 0;
                                }
                                if (prev)
                                        prev->next = n->next;
                                else
                                        e->node = n->next;
                                kfree(n);
                        }
                        return 0;
                }
                prev = n;
                n = n->next;
        }
 
        if (!value)
                return 0;
 
        new = kzalloc(sizeof(*new), GFP_ATOMIC);
        if (!new)
                return -ENOMEM;
 
        new->startbit = bit - (bit % EBITMAP_SIZE);
        ebitmap_node_set_bit(new, bit);
 
        if (!n)
                /* this node will be the highest map within the bitmap */
                e->highbit = new->startbit + EBITMAP_SIZE;
 
        if (prev) {
                new->next = prev->next;
                prev->next = new;
        } else {
                new->next = e->node;
                e->node = new;
        }
 
        return 0;
}
 
void ebitmap_destroy(struct ebitmap *e)
{
        struct ebitmap_node *n, *temp;
 
        if (!e)
                return;
 
        n = e->node;
        while (n) {
                temp = n;
                n = n->next;
                kfree(temp);
        }
 
        e->highbit = 0;
        e->node = NULL;
        return;
}
 
int ebitmap_read(struct ebitmap *e, void *fp)
{
        struct ebitmap_node *n = NULL;
        u32 mapunit, count, startbit, index;
        u64 map;
        __le32 buf[3];
        int rc, i;
 
        ebitmap_init(e);
 
        rc = next_entry(buf, fp, sizeof buf);
        if (rc < 0)
                goto out;
 
        mapunit = le32_to_cpu(buf[0]);
        e->highbit = le32_to_cpu(buf[1]);
        count = le32_to_cpu(buf[2]);
 
        if (mapunit != sizeof(u64) * 8) {
                printk(KERN_ERR "security: ebitmap: map size %u does not "
                       "match my size %Zd (high bit was %d)\n",
                       mapunit, sizeof(u64) * 8, e->highbit);
                goto bad;
        }
 
        /* round up e->highbit */
        e->highbit += EBITMAP_SIZE - 1;
        e->highbit -= (e->highbit % EBITMAP_SIZE);
 
        if (!e->highbit) {
                e->node = NULL;
                goto ok;
        }
 
        for (i = 0; i < count; i++) {
                rc = next_entry(&startbit, fp, sizeof(u32));
                if (rc < 0) {
                        printk(KERN_ERR "security: ebitmap: truncated map\n");
                        goto bad;
                }
                startbit = le32_to_cpu(startbit);
 
                if (startbit & (mapunit - 1)) {
                        printk(KERN_ERR "security: ebitmap start bit (%d) is "
                               "not a multiple of the map unit size (%u)\n",
                               startbit, mapunit);
                        goto bad;
                }
                if (startbit > e->highbit - mapunit) {
                        printk(KERN_ERR "security: ebitmap start bit (%d) is "
                               "beyond the end of the bitmap (%u)\n",
                               startbit, (e->highbit - mapunit));
                        goto bad;
                }
 
                if (!n || startbit >= n->startbit + EBITMAP_SIZE) {
                        struct ebitmap_node *tmp;
                        tmp = kzalloc(sizeof(*tmp), GFP_KERNEL);
                        if (!tmp) {
                                printk(KERN_ERR
                                       "security: ebitmap: out of memory\n");
                                rc = -ENOMEM;
                                goto bad;
                        }
                        /* round down */
                        tmp->startbit = startbit - (startbit % EBITMAP_SIZE);
                        if (n) {
                                n->next = tmp;
                        } else {
                                e->node = tmp;
                        }
                        n = tmp;
                } else if (startbit <= n->startbit) {
                        printk(KERN_ERR "security: ebitmap: start bit %d"
                               " comes after start bit %d\n",
                               startbit, n->startbit);
                        goto bad;
                }
 
                rc = next_entry(&map, fp, sizeof(u64));
                if (rc < 0) {
                        printk(KERN_ERR "security: ebitmap: truncated map\n");
                        goto bad;
                }
                map = le64_to_cpu(map);
 
                index = (startbit - n->startbit) / EBITMAP_UNIT_SIZE;
                while (map) {
                        n->maps[index++] = map & (-1UL);
                        map = EBITMAP_SHIFT_UNIT_SIZE(map);
                }
        }
ok:
        rc = 0;
out:
        return rc;
bad:
        if (!rc)
                rc = -EINVAL;
        ebitmap_destroy(e);
        goto out;
}

Browse

Tools

Subversion Repositories test_project

[/] [test_project/] [trunk/] [linux_sd_driver/] [security/] [selinux/] [ss/] [ebitmap.c] - Blame information for rev 62

Line No.	Rev	Author	Line
1	62	marcus.erl	`/*`
2			`* Implementation of the extensible bitmap type.`
3			`*`
4			`* Author : Stephen Smalley, <sds@epoch.ncsc.mil>`
5			`*/`
6			`/*`
7			`* Updated: Hewlett-Packard <paul.moore@hp.com>`
8			`*`
9			`* Added support to import/export the NetLabel category bitmap`
10			`*`
11			`* (c) Copyright Hewlett-Packard Development Company, L.P., 2006`
12			`*/`
13			`/*`
14			`* Updated: KaiGai Kohei <kaigai@ak.jp.nec.com>`
15			`* Applied standard bit operations to improve bitmap scanning.`
16			`*/`
17
18			`#include <linux/kernel.h>`
19			`#include <linux/slab.h>`
20			`#include <linux/errno.h>`
21			`#include <net/netlabel.h>`
22			`#include "ebitmap.h"`
23			`#include "policydb.h"`
24
25			`int ebitmap_cmp(struct ebitmap e1, struct ebitmap e2)`
26			`{`
27			`struct ebitmap_node n1, n2;`
28
29			`if (e1->highbit != e2->highbit)`
30			`return 0;`
31
32			`n1 = e1->node;`
33			`n2 = e2->node;`
34			`while (n1 && n2 &&`
35			`(n1->startbit == n2->startbit) &&`
36			`!memcmp(n1->maps, n2->maps, EBITMAP_SIZE / 8)) {`
37			`n1 = n1->next;`
38			`n2 = n2->next;`
39			`}`
40
41			`if (n1 \|\| n2)`
42			`return 0;`
43
44			`return 1;`
45			`}`
46
47			`int ebitmap_cpy(struct ebitmap dst, struct ebitmap src)`
48			`{`
49			`struct ebitmap_node n, new, *prev;`
50
51			`ebitmap_init(dst);`
52			`n = src->node;`
53			`prev = NULL;`
54			`while (n) {`
55			`new = kzalloc(sizeof(*new), GFP_ATOMIC);`
56			`if (!new) {`
57			`ebitmap_destroy(dst);`
58			`return -ENOMEM;`
59			`}`
60			`new->startbit = n->startbit;`
61			`memcpy(new->maps, n->maps, EBITMAP_SIZE / 8);`
62			`new->next = NULL;`
63			`if (prev)`
64			`prev->next = new;`
65			`else`
66			`dst->node = new;`
67			`prev = new;`
68			`n = n->next;`
69			`}`
70
71			`dst->highbit = src->highbit;`
72			`return 0;`
73			`}`
74
75			`#ifdef CONFIG_NETLABEL`
76			`/**`
77			`* ebitmap_netlbl_export - Export an ebitmap into a NetLabel category bitmap`
78			`* @ebmap: the ebitmap to export`
79			`* @catmap: the NetLabel category bitmap`
80			`*`
81			`* Description:`
82			`* Export a SELinux extensibile bitmap into a NetLabel category bitmap.`
83			`* Returns zero on success, negative values on error.`
84			`*`
85			`*/`
86			`int ebitmap_netlbl_export(struct ebitmap *ebmap,`
87			`struct netlbl_lsm_secattr_catmap **catmap)`
88			`{`
89			`struct ebitmap_node *e_iter = ebmap->node;`
90			`struct netlbl_lsm_secattr_catmap *c_iter;`
91			`u32 cmap_idx, cmap_sft;`
92			`int i;`
93
94			`/* NetLabel's NETLBL_CATMAP_MAPTYPE is defined as an array of u64,`
95			`* however, it is not always compatible with an array of unsigned long`
96			`* in ebitmap_node.`
97			`* In addition, you should pay attention the following implementation`
98			`* assumes unsigned long has a width equal with or less than 64-bit.`
99			`*/`
100
101			`if (e_iter == NULL) {`
102			`*catmap = NULL;`
103			`return 0;`
104			`}`
105
106			`c_iter = netlbl_secattr_catmap_alloc(GFP_ATOMIC);`
107			`if (c_iter == NULL)`
108			`return -ENOMEM;`
109			`*catmap = c_iter;`
110			`c_iter->startbit = e_iter->startbit & ~(NETLBL_CATMAP_SIZE - 1);`
111
112			`while (e_iter != NULL) {`
113			`for (i = 0; i < EBITMAP_UNIT_NUMS; i++) {`
114			`unsigned int delta, e_startbit, c_endbit;`
115
116			`e_startbit = e_iter->startbit + i * EBITMAP_UNIT_SIZE;`
117			`c_endbit = c_iter->startbit + NETLBL_CATMAP_SIZE;`
118			`if (e_startbit >= c_endbit) {`
119			`c_iter->next`
120			`= netlbl_secattr_catmap_alloc(GFP_ATOMIC);`
121			`if (c_iter->next == NULL)`
122			`goto netlbl_export_failure;`
123			`c_iter = c_iter->next;`
124			`c_iter->startbit`
125			`= e_startbit & ~(NETLBL_CATMAP_SIZE - 1);`
126			`}`
127			`delta = e_startbit - c_iter->startbit;`
128			`cmap_idx = delta / NETLBL_CATMAP_MAPSIZE;`
129			`cmap_sft = delta % NETLBL_CATMAP_MAPSIZE;`
130			`c_iter->bitmap[cmap_idx]`
131			`\|= e_iter->maps[cmap_idx] << cmap_sft;`
132			`}`
133			`e_iter = e_iter->next;`
134			`}`
135
136			`return 0;`
137
138			`netlbl_export_failure:`
139			`netlbl_secattr_catmap_free(*catmap);`
140			`return -ENOMEM;`
141			`}`
142
143			`/**`
144			`* ebitmap_netlbl_import - Import a NetLabel category bitmap into an ebitmap`
145			`* @ebmap: the ebitmap to import`
146			`* @catmap: the NetLabel category bitmap`
147			`*`
148			`* Description:`
149			`* Import a NetLabel category bitmap into a SELinux extensibile bitmap.`
150			`* Returns zero on success, negative values on error.`
151			`*`
152			`*/`
153			`int ebitmap_netlbl_import(struct ebitmap *ebmap,`
154			`struct netlbl_lsm_secattr_catmap *catmap)`
155			`{`
156			`struct ebitmap_node *e_iter = NULL;`
157			`struct ebitmap_node *emap_prev = NULL;`
158			`struct netlbl_lsm_secattr_catmap *c_iter = catmap;`
159			`u32 c_idx, c_pos, e_idx, e_sft;`
160
161			`/* NetLabel's NETLBL_CATMAP_MAPTYPE is defined as an array of u64,`
162			`* however, it is not always compatible with an array of unsigned long`
163			`* in ebitmap_node.`
164			`* In addition, you should pay attention the following implementation`
165			`* assumes unsigned long has a width equal with or less than 64-bit.`
166			`*/`
167
168			`do {`
169			`for (c_idx = 0; c_idx < NETLBL_CATMAP_MAPCNT; c_idx++) {`
170			`unsigned int delta;`
171			`u64 map = c_iter->bitmap[c_idx];`
172
173			`if (!map)`
174			`continue;`
175
176			`c_pos = c_iter->startbit`
177			`+ c_idx * NETLBL_CATMAP_MAPSIZE;`
178			`if (!e_iter`
179			`\|\| c_pos >= e_iter->startbit + EBITMAP_SIZE) {`
180			`e_iter = kzalloc(sizeof(*e_iter), GFP_ATOMIC);`
181			`if (!e_iter)`
182			`goto netlbl_import_failure;`
183			`e_iter->startbit`
184			`= c_pos - (c_pos % EBITMAP_SIZE);`
185			`if (emap_prev == NULL)`
186			`ebmap->node = e_iter;`
187			`else`
188			`emap_prev->next = e_iter;`
189			`emap_prev = e_iter;`
190			`}`
191			`delta = c_pos - e_iter->startbit;`
192			`e_idx = delta / EBITMAP_UNIT_SIZE;`
193			`e_sft = delta % EBITMAP_UNIT_SIZE;`
194			`while (map) {`
195			`e_iter->maps[e_idx++] \|= map & (-1UL);`
196			`map = EBITMAP_SHIFT_UNIT_SIZE(map);`
197			`}`
198			`}`
199			`c_iter = c_iter->next;`
200			`} while (c_iter != NULL);`
201			`if (e_iter != NULL)`
202			`ebmap->highbit = e_iter->startbit + EBITMAP_SIZE;`
203			`else`
204			`ebitmap_destroy(ebmap);`
205
206			`return 0;`
207
208			`netlbl_import_failure:`
209			`ebitmap_destroy(ebmap);`
210			`return -ENOMEM;`
211			`}`
212			`#endif /* CONFIG_NETLABEL */`
213
214			`int ebitmap_contains(struct ebitmap e1, struct ebitmap e2)`
215			`{`
216			`struct ebitmap_node n1, n2;`
217			`int i;`
218
219			`if (e1->highbit < e2->highbit)`
220			`return 0;`
221
222			`n1 = e1->node;`
223			`n2 = e2->node;`
224			`while (n1 && n2 && (n1->startbit <= n2->startbit)) {`
225			`if (n1->startbit < n2->startbit) {`
226			`n1 = n1->next;`
227			`continue;`
228			`}`
229			`for (i = 0; i < EBITMAP_UNIT_NUMS; i++) {`
230			`if ((n1->maps[i] & n2->maps[i]) != n2->maps[i])`
231			`return 0;`
232			`}`
233
234			`n1 = n1->next;`
235			`n2 = n2->next;`
236			`}`
237
238			`if (n2)`
239			`return 0;`
240
241			`return 1;`
242			`}`
243
244			`int ebitmap_get_bit(struct ebitmap *e, unsigned long bit)`
245			`{`
246			`struct ebitmap_node *n;`
247
248			`if (e->highbit < bit)`
249			`return 0;`
250
251			`n = e->node;`
252			`while (n && (n->startbit <= bit)) {`
253			`if ((n->startbit + EBITMAP_SIZE) > bit)`
254			`return ebitmap_node_get_bit(n, bit);`
255			`n = n->next;`
256			`}`
257
258			`return 0;`
259			`}`
260
261			`int ebitmap_set_bit(struct ebitmap *e, unsigned long bit, int value)`
262			`{`
263			`struct ebitmap_node n, prev, *new;`
264
265			`prev = NULL;`
266			`n = e->node;`
267			`while (n && n->startbit <= bit) {`
268			`if ((n->startbit + EBITMAP_SIZE) > bit) {`
269			`if (value) {`
270			`ebitmap_node_set_bit(n, bit);`
271			`} else {`
272			`unsigned int s;`
273
274			`ebitmap_node_clr_bit(n, bit);`
275
276			`s = find_first_bit(n->maps, EBITMAP_SIZE);`
277			`if (s < EBITMAP_SIZE)`
278			`return 0;`
279
280			`/* drop this node from the bitmap */`
281			`if (!n->next) {`
282			`/*`
283			`* this was the highest map`
284			`* within the bitmap`
285			`*/`
286			`if (prev)`
287			`e->highbit = prev->startbit`
288			`+ EBITMAP_SIZE;`
289			`else`
290			`e->highbit = 0;`
291			`}`
292			`if (prev)`
293			`prev->next = n->next;`
294			`else`
295			`e->node = n->next;`
296			`kfree(n);`
297			`}`
298			`return 0;`
299			`}`
300			`prev = n;`
301			`n = n->next;`
302			`}`
303
304			`if (!value)`
305			`return 0;`
306
307			`new = kzalloc(sizeof(*new), GFP_ATOMIC);`
308			`if (!new)`
309			`return -ENOMEM;`
310
311			`new->startbit = bit - (bit % EBITMAP_SIZE);`
312			`ebitmap_node_set_bit(new, bit);`
313
314			`if (!n)`
315			`/* this node will be the highest map within the bitmap */`
316			`e->highbit = new->startbit + EBITMAP_SIZE;`
317
318			`if (prev) {`
319			`new->next = prev->next;`
320			`prev->next = new;`
321			`} else {`
322			`new->next = e->node;`
323			`e->node = new;`
324			`}`
325
326			`return 0;`
327			`}`
328
329			`void ebitmap_destroy(struct ebitmap *e)`
330			`{`
331			`struct ebitmap_node n, temp;`
332
333			`if (!e)`
334			`return;`
335
336			`n = e->node;`
337			`while (n) {`
338			`temp = n;`
339			`n = n->next;`
340			`kfree(temp);`
341			`}`
342
343			`e->highbit = 0;`
344			`e->node = NULL;`
345			`return;`
346			`}`
347
348			`int ebitmap_read(struct ebitmap e, void fp)`
349			`{`
350			`struct ebitmap_node *n = NULL;`
351			`u32 mapunit, count, startbit, index;`
352			`u64 map;`
353			`__le32 buf[3];`
354			`int rc, i;`
355
356			`ebitmap_init(e);`
357
358			`rc = next_entry(buf, fp, sizeof buf);`
359			`if (rc < 0)`
360			`goto out;`
361
362			`mapunit = le32_to_cpu(buf[0]);`
363			`e->highbit = le32_to_cpu(buf[1]);`
364			`count = le32_to_cpu(buf[2]);`
365
366			`if (mapunit != sizeof(u64) * 8) {`
367			`printk(KERN_ERR "security: ebitmap: map size %u does not "`
368			`"match my size %Zd (high bit was %d)\n",`
369			`mapunit, sizeof(u64) * 8, e->highbit);`
370			`goto bad;`
371			`}`
372
373			`/* round up e->highbit */`
374			`e->highbit += EBITMAP_SIZE - 1;`
375			`e->highbit -= (e->highbit % EBITMAP_SIZE);`
376
377			`if (!e->highbit) {`
378			`e->node = NULL;`
379			`goto ok;`
380			`}`
381
382			`for (i = 0; i < count; i++) {`
383			`rc = next_entry(&startbit, fp, sizeof(u32));`
384			`if (rc < 0) {`
385			`printk(KERN_ERR "security: ebitmap: truncated map\n");`
386			`goto bad;`
387			`}`
388			`startbit = le32_to_cpu(startbit);`
389
390			`if (startbit & (mapunit - 1)) {`
391			`printk(KERN_ERR "security: ebitmap start bit (%d) is "`
392			`"not a multiple of the map unit size (%u)\n",`
393			`startbit, mapunit);`
394			`goto bad;`
395			`}`
396			`if (startbit > e->highbit - mapunit) {`
397			`printk(KERN_ERR "security: ebitmap start bit (%d) is "`
398			`"beyond the end of the bitmap (%u)\n",`
399			`startbit, (e->highbit - mapunit));`
400			`goto bad;`
401			`}`
402
403			`if (!n \|\| startbit >= n->startbit + EBITMAP_SIZE) {`
404			`struct ebitmap_node *tmp;`
405			`tmp = kzalloc(sizeof(*tmp), GFP_KERNEL);`
406			`if (!tmp) {`
407			`printk(KERN_ERR`
408			`"security: ebitmap: out of memory\n");`
409			`rc = -ENOMEM;`
410			`goto bad;`
411			`}`
412			`/* round down */`
413			`tmp->startbit = startbit - (startbit % EBITMAP_SIZE);`
414			`if (n) {`
415			`n->next = tmp;`
416			`} else {`
417			`e->node = tmp;`
418			`}`
419			`n = tmp;`
420			`} else if (startbit <= n->startbit) {`
421			`printk(KERN_ERR "security: ebitmap: start bit %d"`
422			`" comes after start bit %d\n",`
423			`startbit, n->startbit);`
424			`goto bad;`
425			`}`
426
427			`rc = next_entry(&map, fp, sizeof(u64));`
428			`if (rc < 0) {`
429			`printk(KERN_ERR "security: ebitmap: truncated map\n");`
430			`goto bad;`
431			`}`
432			`map = le64_to_cpu(map);`
433
434			`index = (startbit - n->startbit) / EBITMAP_UNIT_SIZE;`
435			`while (map) {`
436			`n->maps[index++] = map & (-1UL);`
437			`map = EBITMAP_SHIFT_UNIT_SIZE(map);`
438			`}`
439			`}`
440			`ok:`
441			`rc = 0;`
442			`out:`
443			`return rc;`
444			`bad:`
445			`if (!rc)`
446			`rc = -EINVAL;`
447			`ebitmap_destroy(e);`
448			`goto out;`
449			`}`