diff options
Diffstat (limited to 'sys/kern/subr_capability.c')
| -rw-r--r-- | sys/kern/subr_capability.c | 285 |
1 files changed, 285 insertions, 0 deletions
diff --git a/sys/kern/subr_capability.c b/sys/kern/subr_capability.c new file mode 100644 index 000000000000..7043fe7ae470 --- /dev/null +++ b/sys/kern/subr_capability.c @@ -0,0 +1,285 @@ +/*- + * Copyright (c) 2013 FreeBSD Foundation + * All rights reserved. + * + * This software was developed by Pawel Jakub Dawidek under sponsorship from + * the FreeBSD Foundation. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +#ifdef _KERNEL +#include <sys/types.h> +#include <sys/capability.h> +#include <sys/systm.h> + +#include <machine/stdarg.h> +#else /* !_KERNEL */ +#include <sys/types.h> +#include <sys/capability.h> + +#include <assert.h> +#include <stdarg.h> +#include <stdbool.h> +#include <stdint.h> +#include <string.h> +#endif + +#ifdef _KERNEL +#define assert(exp) KASSERT((exp), ("%s:%u", __func__, __LINE__)) +#endif + +static __inline unsigned int +right_to_index(uint64_t right) +{ + static const int bit2idx[] = { + -1, 0, 1, -1, 2, -1, -1, -1, 3, -1, -1, -1, -1, -1, -1, -1, + 4, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 + }; + int idx; + + idx = CAPIDXBIT(right); + assert(idx == 1 || idx == 2 || idx == 4 || idx == 8 || idx == 16); + + idx = bit2idx[idx]; + assert(idx >= 0 && idx <= 4); + + return ((unsigned int)idx); +} + +static void +cap_rights_vset(cap_rights_t *rights, va_list ap) +{ + unsigned int i, n; + uint64_t right; + + assert(CAPVER(rights) == CAP_RIGHTS_VERSION_00); + + n = CAPARSIZE(rights); + + for (;;) { + right = (uint64_t)va_arg(ap, unsigned long long); + if (right == 0) + break; + assert(CAPRVER(right) == 0); + i = right_to_index(right); + assert(i < n); + assert(CAPIDXBIT(rights->cr_rights[i]) == CAPIDXBIT(right)); + rights->cr_rights[i] |= right; + assert(CAPIDXBIT(rights->cr_rights[i]) == CAPIDXBIT(right)); + } +} + +static void +cap_rights_vclear(cap_rights_t *rights, va_list ap) +{ + unsigned int i, n; + uint64_t right; + + assert(CAPVER(rights) == CAP_RIGHTS_VERSION_00); + + n = CAPARSIZE(rights); + + for (;;) { + right = (uint64_t)va_arg(ap, unsigned long long); + if (right == 0) + break; + assert(CAPRVER(right) == 0); + i = right_to_index(right); + assert(i < n); + assert(CAPIDXBIT(rights->cr_rights[i]) == CAPIDXBIT(right)); + rights->cr_rights[i] &= ~(right & 0x01FFFFFFFFFFFFFFULL); + assert(CAPIDXBIT(rights->cr_rights[i]) == CAPIDXBIT(right)); + } +} + +static bool +cap_rights_is_vset(const cap_rights_t *rights, va_list ap) +{ + unsigned int i, n; + uint64_t right; + + assert(CAPVER(rights) == CAP_RIGHTS_VERSION_00); + + n = CAPARSIZE(rights); + + for (;;) { + right = (uint64_t)va_arg(ap, unsigned long long); + if (right == 0) + break; + assert(CAPRVER(right) == 0); + i = right_to_index(right); + assert(i < n); + assert(CAPIDXBIT(rights->cr_rights[i]) == CAPIDXBIT(right)); + if ((rights->cr_rights[i] & right) != right) + return (false); + } + + return (true); +} + +cap_rights_t * +__cap_rights_init(int version, cap_rights_t *rights, ...) +{ + unsigned int n; + va_list ap; + + assert(version == CAP_RIGHTS_VERSION_00); + + n = version + 2; + memset(rights->cr_rights, 0, sizeof(rights->cr_rights[0]) * n); + CAP_NONE(rights); + va_start(ap, rights); + cap_rights_vset(rights, ap); + va_end(ap); + + return (rights); +} + +void +__cap_rights_set(cap_rights_t *rights, ...) +{ + va_list ap; + + assert(CAPVER(rights) == CAP_RIGHTS_VERSION_00); + + va_start(ap, rights); + cap_rights_vset(rights, ap); + va_end(ap); +} + +void +__cap_rights_clear(cap_rights_t *rights, ...) +{ + va_list ap; + + assert(CAPVER(rights) == CAP_RIGHTS_VERSION_00); + + va_start(ap, rights); + cap_rights_vclear(rights, ap); + va_end(ap); +} + +bool +__cap_rights_is_set(const cap_rights_t *rights, ...) +{ + va_list ap; + bool ret; + + assert(CAPVER(rights) == CAP_RIGHTS_VERSION_00); + + va_start(ap, rights); + ret = cap_rights_is_vset(rights, ap); + va_end(ap); + + return (ret); +} + +bool +cap_rights_is_valid(const cap_rights_t *rights) +{ + cap_rights_t allrights; + unsigned int i, j; + + if (CAPVER(rights) != CAP_RIGHTS_VERSION_00) + return (false); + CAP_ALL(&allrights); + if (!cap_rights_contains(&allrights, rights)) + return (false); + for (i = 0; i < CAPARSIZE(rights); i++) { + j = right_to_index(rights->cr_rights[i]); + if (i != j) + return (false); + if (i > 0) { + if (CAPRVER(rights->cr_rights[i]) != 0) + return (false); + } + } + + return (true); +} + +void +cap_rights_merge(cap_rights_t *dst, const cap_rights_t *src) +{ + unsigned int i, n; + + assert(CAPVER(dst) == CAP_RIGHTS_VERSION_00); + assert(CAPVER(src) == CAP_RIGHTS_VERSION_00); + assert(CAPVER(dst) == CAPVER(src)); + assert(cap_rights_is_valid(src)); + assert(cap_rights_is_valid(dst)); + + n = CAPARSIZE(dst); + + for (i = 0; i < n; i++) + dst->cr_rights[i] |= src->cr_rights[i]; + + assert(cap_rights_is_valid(src)); + assert(cap_rights_is_valid(dst)); +} + +void +cap_rights_remove(cap_rights_t *dst, const cap_rights_t *src) +{ + unsigned int i, n; + + assert(CAPVER(dst) == CAP_RIGHTS_VERSION_00); + assert(CAPVER(src) == CAP_RIGHTS_VERSION_00); + assert(CAPVER(dst) == CAPVER(src)); + assert(cap_rights_is_valid(src)); + assert(cap_rights_is_valid(dst)); + + n = CAPARSIZE(dst); + + for (i = 0; i < n; i++) { + dst->cr_rights[i] &= + ~(src->cr_rights[i] & 0x01FFFFFFFFFFFFFFULL); + } + + assert(cap_rights_is_valid(src)); + assert(cap_rights_is_valid(dst)); +} + +bool +cap_rights_contains(const cap_rights_t *big, const cap_rights_t *little) +{ + unsigned int i, n; + + assert(CAPVER(big) == CAP_RIGHTS_VERSION_00); + assert(CAPVER(little) == CAP_RIGHTS_VERSION_00); + assert(CAPVER(big) == CAPVER(little)); + + n = CAPARSIZE(big); + + for (i = 0; i < n; i++) { + if ((big->cr_rights[i] & little->cr_rights[i]) != + little->cr_rights[i]) { + return (false); + } + } + + return (true); +} |