| /* |
| * Copyright (c) 1997-8,2008 Andrew G. Morgan <morgan@kernel.org> |
| * |
| * This file deals with flipping of capabilities on internal |
| * capability sets as specified by POSIX.1e (formerlly, POSIX 6). |
| */ |
| |
| #include "libcap.h" |
| |
| /* |
| * Return the state of a specified capability flag. The state is |
| * returned as the contents of *raised. The capability is from one of |
| * the sets stored in cap_d as specified by set and value |
| */ |
| |
| int cap_get_flag(cap_t cap_d, cap_value_t value, cap_flag_t set, |
| cap_flag_value_t *raised) |
| { |
| /* |
| * Do we have a set and a place to store its value? |
| * Is it a known capability? |
| */ |
| |
| if (raised && good_cap_t(cap_d) && value >= 0 && value < __CAP_BITS |
| && set >= 0 && set < NUMBER_OF_CAP_SETS) { |
| *raised = isset_cap(cap_d,value,set) ? CAP_SET:CAP_CLEAR; |
| return 0; |
| } else { |
| _cap_debug("invalid arguments"); |
| errno = EINVAL; |
| return -1; |
| } |
| } |
| |
| /* |
| * raise/lower a selection of capabilities |
| */ |
| |
| int cap_set_flag(cap_t cap_d, cap_flag_t set, |
| int no_values, const cap_value_t *array_values, |
| cap_flag_value_t raise) |
| { |
| /* |
| * Do we have a set and a place to store its value? |
| * Is it a known capability? |
| */ |
| |
| if (good_cap_t(cap_d) && no_values > 0 && no_values <= __CAP_BITS |
| && (set >= 0) && (set < NUMBER_OF_CAP_SETS) |
| && (raise == CAP_SET || raise == CAP_CLEAR) ) { |
| int i; |
| for (i=0; i<no_values; ++i) { |
| if (array_values[i] < 0 || array_values[i] >= __CAP_BITS) { |
| _cap_debug("weird capability (%d) - skipped", array_values[i]); |
| } else { |
| int value = array_values[i]; |
| |
| if (raise == CAP_SET) { |
| cap_d->raise_cap(value,set); |
| } else { |
| cap_d->lower_cap(value,set); |
| } |
| } |
| } |
| return 0; |
| |
| } else { |
| |
| _cap_debug("invalid arguments"); |
| errno = EINVAL; |
| return -1; |
| |
| } |
| } |
| |
| /* |
| * Reset the capability to be empty (nothing raised) |
| */ |
| |
| int cap_clear(cap_t cap_d) |
| { |
| if (good_cap_t(cap_d)) { |
| |
| memset(&(cap_d->u), 0, sizeof(cap_d->u)); |
| return 0; |
| |
| } else { |
| |
| _cap_debug("invalid pointer"); |
| errno = EINVAL; |
| return -1; |
| |
| } |
| } |
| |
| /* |
| * Reset the all of the capability bits for one of the flag sets |
| */ |
| |
| int cap_clear_flag(cap_t cap_d, cap_flag_t flag) |
| { |
| switch (flag) { |
| case CAP_EFFECTIVE: |
| case CAP_PERMITTED: |
| case CAP_INHERITABLE: |
| if (good_cap_t(cap_d)) { |
| unsigned i; |
| |
| for (i=0; i<_LIBCAP_CAPABILITY_U32S; i++) { |
| cap_d->u[i].flat[flag] = 0; |
| } |
| return 0; |
| } |
| /* |
| * fall through |
| */ |
| |
| default: |
| _cap_debug("invalid pointer"); |
| errno = EINVAL; |
| return -1; |
| } |
| } |
| |
| /* |
| * Compare two capability sets |
| */ |
| |
| int cap_compare(cap_t a, cap_t b) |
| { |
| unsigned i; |
| int result; |
| |
| if (!(good_cap_t(a) && good_cap_t(b))) { |
| _cap_debug("invalid arguments"); |
| errno = EINVAL; |
| return -1; |
| } |
| |
| for (i=0, result=0; i<_LIBCAP_CAPABILITY_U32S; i++) { |
| result |= |
| ((a->u[i].flat[CAP_EFFECTIVE] != b->u[i].flat[CAP_EFFECTIVE]) |
| ? LIBCAP_EFF : 0) |
| | ((a->u[i].flat[CAP_INHERITABLE] != b->u[i].flat[CAP_INHERITABLE]) |
| ? LIBCAP_INH : 0) |
| | ((a->u[i].flat[CAP_PERMITTED] != b->u[i].flat[CAP_PERMITTED]) |
| ? LIBCAP_PER : 0); |
| } |
| return result; |
| } |