diff options
Diffstat (limited to 'security/selinux/ss/ebitmap.c')
| -rw-r--r-- | security/selinux/ss/ebitmap.c | 105 |
1 files changed, 99 insertions, 6 deletions
diff --git a/security/selinux/ss/ebitmap.c b/security/selinux/ss/ebitmap.c index 68c7348d1ac..820313a04d4 100644 --- a/security/selinux/ss/ebitmap.c +++ b/security/selinux/ss/ebitmap.c @@ -4,7 +4,7 @@ * Author : Stephen Smalley, <sds@epoch.ncsc.mil> */ /* - * Updated: Hewlett-Packard <paul.moore@hp.com> + * Updated: Hewlett-Packard <paul@paul-moore.com> * * Added support to import/export the NetLabel category bitmap * @@ -22,6 +22,8 @@ #include "ebitmap.h" #include "policydb.h" +#define BITS_PER_U64 (sizeof(u64) * 8) + int ebitmap_cmp(struct ebitmap *e1, struct ebitmap *e2) { struct ebitmap_node *n1, *n2; @@ -128,7 +130,7 @@ int ebitmap_netlbl_export(struct ebitmap *ebmap, 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->maps[i] << cmap_sft; } e_iter = e_iter->next; } @@ -211,7 +213,12 @@ netlbl_import_failure: } #endif /* CONFIG_NETLABEL */ -int ebitmap_contains(struct ebitmap *e1, struct ebitmap *e2) +/* + * Check to see if all the bits set in e2 are also set in e1. Optionally, + * if last_e2bit is non-zero, the highest set bit in e2 cannot exceed + * last_e2bit. + */ +int ebitmap_contains(struct ebitmap *e1, struct ebitmap *e2, u32 last_e2bit) { struct ebitmap_node *n1, *n2; int i; @@ -221,14 +228,25 @@ int ebitmap_contains(struct ebitmap *e1, struct ebitmap *e2) 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++) { + for (i = EBITMAP_UNIT_NUMS - 1; (i >= 0) && !n2->maps[i]; ) + i--; /* Skip trailing NULL map entries */ + if (last_e2bit && (i >= 0)) { + u32 lastsetbit = n2->startbit + i * EBITMAP_UNIT_SIZE + + __fls(n2->maps[i]); + if (lastsetbit > last_e2bit) + return 0; + } + + while (i >= 0) { if ((n1->maps[i] & n2->maps[i]) != n2->maps[i]) return 0; + i--; } n1 = n1->next; @@ -363,10 +381,10 @@ int ebitmap_read(struct ebitmap *e, void *fp) e->highbit = le32_to_cpu(buf[1]); count = le32_to_cpu(buf[2]); - if (mapunit != sizeof(u64) * 8) { + if (mapunit != BITS_PER_U64) { printk(KERN_ERR "SELinux: ebitmap: map size %u does not " "match my size %Zd (high bit was %d)\n", - mapunit, sizeof(u64) * 8, e->highbit); + mapunit, BITS_PER_U64, e->highbit); goto bad; } @@ -446,3 +464,78 @@ bad: ebitmap_destroy(e); goto out; } + +int ebitmap_write(struct ebitmap *e, void *fp) +{ + struct ebitmap_node *n; + u32 count; + __le32 buf[3]; + u64 map; + int bit, last_bit, last_startbit, rc; + + buf[0] = cpu_to_le32(BITS_PER_U64); + + count = 0; + last_bit = 0; + last_startbit = -1; + ebitmap_for_each_positive_bit(e, n, bit) { + if (rounddown(bit, (int)BITS_PER_U64) > last_startbit) { + count++; + last_startbit = rounddown(bit, BITS_PER_U64); + } + last_bit = roundup(bit + 1, BITS_PER_U64); + } + buf[1] = cpu_to_le32(last_bit); + buf[2] = cpu_to_le32(count); + + rc = put_entry(buf, sizeof(u32), 3, fp); + if (rc) + return rc; + + map = 0; + last_startbit = INT_MIN; + ebitmap_for_each_positive_bit(e, n, bit) { + if (rounddown(bit, (int)BITS_PER_U64) > last_startbit) { + __le64 buf64[1]; + + /* this is the very first bit */ + if (!map) { + last_startbit = rounddown(bit, BITS_PER_U64); + map = (u64)1 << (bit - last_startbit); + continue; + } + + /* write the last node */ + buf[0] = cpu_to_le32(last_startbit); + rc = put_entry(buf, sizeof(u32), 1, fp); + if (rc) + return rc; + + buf64[0] = cpu_to_le64(map); + rc = put_entry(buf64, sizeof(u64), 1, fp); + if (rc) + return rc; + + /* set up for the next node */ + map = 0; + last_startbit = rounddown(bit, BITS_PER_U64); + } + map |= (u64)1 << (bit - last_startbit); + } + /* write the last node */ + if (map) { + __le64 buf64[1]; + + /* write the last node */ + buf[0] = cpu_to_le32(last_startbit); + rc = put_entry(buf, sizeof(u32), 1, fp); + if (rc) + return rc; + + buf64[0] = cpu_to_le64(map); + rc = put_entry(buf64, sizeof(u64), 1, fp); + if (rc) + return rc; + } + return 0; +} |