Stephen Smalley | f074036 | 2012-01-04 12:30:47 -0500 | [diff] [blame] | 1 | #include <unistd.h> |
| 2 | #include <sys/types.h> |
| 3 | #include <fcntl.h> |
| 4 | #include <stdlib.h> |
| 5 | #include <stdio.h> |
| 6 | #include <errno.h> |
| 7 | #include <string.h> |
| 8 | #include <limits.h> |
| 9 | #include "selinux_internal.h" |
| 10 | #include "policy.h" |
| 11 | #include "mapping.h" |
| 12 | |
| 13 | int security_compute_av(const security_context_t scon, |
| 14 | const security_context_t tcon, |
| 15 | security_class_t tclass, |
| 16 | access_vector_t requested, |
| 17 | struct av_decision *avd) |
| 18 | { |
| 19 | char path[PATH_MAX]; |
| 20 | char *buf; |
| 21 | size_t len; |
| 22 | int fd, ret; |
| 23 | |
| 24 | if (!selinux_mnt) { |
| 25 | errno = ENOENT; |
| 26 | return -1; |
| 27 | } |
| 28 | |
| 29 | snprintf(path, sizeof path, "%s/access", selinux_mnt); |
| 30 | fd = open(path, O_RDWR); |
| 31 | if (fd < 0) |
| 32 | return -1; |
| 33 | |
| 34 | len = selinux_page_size; |
| 35 | buf = malloc(len); |
| 36 | if (!buf) { |
| 37 | ret = -1; |
| 38 | goto out; |
| 39 | } |
| 40 | |
| 41 | snprintf(buf, len, "%s %s %hu %x", scon, tcon, |
| 42 | unmap_class(tclass), unmap_perm(tclass, requested)); |
| 43 | |
| 44 | ret = write(fd, buf, strlen(buf)); |
| 45 | if (ret < 0) |
| 46 | goto out2; |
| 47 | |
| 48 | memset(buf, 0, len); |
| 49 | ret = read(fd, buf, len - 1); |
| 50 | if (ret < 0) |
| 51 | goto out2; |
| 52 | |
| 53 | ret = sscanf(buf, "%x %x %x %x %u %x", |
| 54 | &avd->allowed, &avd->decided, |
| 55 | &avd->auditallow, &avd->auditdeny, |
| 56 | &avd->seqno, &avd->flags); |
| 57 | if (ret < 5) { |
| 58 | ret = -1; |
| 59 | goto out2; |
| 60 | } else if (ret < 6) |
| 61 | avd->flags = 0; |
| 62 | |
| 63 | map_decision(tclass, avd); |
| 64 | |
| 65 | ret = 0; |
| 66 | out2: |
| 67 | free(buf); |
| 68 | out: |
| 69 | close(fd); |
| 70 | return ret; |
| 71 | } |
| 72 | |