diff options
author | Luke Shumaker <lukeshu@sbcglobal.net> | 2016-06-01 15:52:09 -0400 |
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committer | Luke Shumaker <lukeshu@sbcglobal.net> | 2016-06-01 15:52:09 -0400 |
commit | bb110bc7433adeb79b4814ef2a1c04e2160be396 (patch) | |
tree | c45048907133b8bbd7e2d86b350436a9ad0ffe8b /src/libshared/acl-util.c | |
parent | 192d82912f055a2b4a2b5c02f0ef69b002322bba (diff) |
./move.sh
Diffstat (limited to 'src/libshared/acl-util.c')
-rw-r--r-- | src/libshared/acl-util.c | 429 |
1 files changed, 429 insertions, 0 deletions
diff --git a/src/libshared/acl-util.c b/src/libshared/acl-util.c new file mode 100644 index 0000000000..2aa951fce9 --- /dev/null +++ b/src/libshared/acl-util.c @@ -0,0 +1,429 @@ +/*** + This file is part of systemd. + + Copyright 2011,2013 Lennart Poettering + + systemd is free software; you can redistribute it and/or modify it + under the terms of the GNU Lesser General Public License as published by + the Free Software Foundation; either version 2.1 of the License, or + (at your option) any later version. + + systemd is distributed in the hope that it will be useful, but + WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public License + along with systemd; If not, see <http://www.gnu.org/licenses/>. +***/ + +#include <errno.h> +#include <stdbool.h> + +#include "acl-util.h" +#include "alloc-util.h" +#include "string-util.h" +#include "strv.h" +#include "user-util.h" +#include "util.h" + +int acl_find_uid(acl_t acl, uid_t uid, acl_entry_t *entry) { + acl_entry_t i; + int r; + + assert(acl); + assert(entry); + + for (r = acl_get_entry(acl, ACL_FIRST_ENTRY, &i); + r > 0; + r = acl_get_entry(acl, ACL_NEXT_ENTRY, &i)) { + + acl_tag_t tag; + uid_t *u; + bool b; + + if (acl_get_tag_type(i, &tag) < 0) + return -errno; + + if (tag != ACL_USER) + continue; + + u = acl_get_qualifier(i); + if (!u) + return -errno; + + b = *u == uid; + acl_free(u); + + if (b) { + *entry = i; + return 1; + } + } + if (r < 0) + return -errno; + + return 0; +} + +int calc_acl_mask_if_needed(acl_t *acl_p) { + acl_entry_t i; + int r; + bool need = false; + + assert(acl_p); + + for (r = acl_get_entry(*acl_p, ACL_FIRST_ENTRY, &i); + r > 0; + r = acl_get_entry(*acl_p, ACL_NEXT_ENTRY, &i)) { + acl_tag_t tag; + + if (acl_get_tag_type(i, &tag) < 0) + return -errno; + + if (tag == ACL_MASK) + return 0; + + if (IN_SET(tag, ACL_USER, ACL_GROUP)) + need = true; + } + if (r < 0) + return -errno; + + if (need && acl_calc_mask(acl_p) < 0) + return -errno; + + return need; +} + +int add_base_acls_if_needed(acl_t *acl_p, const char *path) { + acl_entry_t i; + int r; + bool have_user_obj = false, have_group_obj = false, have_other = false; + struct stat st; + _cleanup_(acl_freep) acl_t basic = NULL; + + assert(acl_p); + + for (r = acl_get_entry(*acl_p, ACL_FIRST_ENTRY, &i); + r > 0; + r = acl_get_entry(*acl_p, ACL_NEXT_ENTRY, &i)) { + acl_tag_t tag; + + if (acl_get_tag_type(i, &tag) < 0) + return -errno; + + if (tag == ACL_USER_OBJ) + have_user_obj = true; + else if (tag == ACL_GROUP_OBJ) + have_group_obj = true; + else if (tag == ACL_OTHER) + have_other = true; + if (have_user_obj && have_group_obj && have_other) + return 0; + } + if (r < 0) + return -errno; + + r = stat(path, &st); + if (r < 0) + return -errno; + + basic = acl_from_mode(st.st_mode); + if (!basic) + return -errno; + + for (r = acl_get_entry(basic, ACL_FIRST_ENTRY, &i); + r > 0; + r = acl_get_entry(basic, ACL_NEXT_ENTRY, &i)) { + acl_tag_t tag; + acl_entry_t dst; + + if (acl_get_tag_type(i, &tag) < 0) + return -errno; + + if ((tag == ACL_USER_OBJ && have_user_obj) || + (tag == ACL_GROUP_OBJ && have_group_obj) || + (tag == ACL_OTHER && have_other)) + continue; + + r = acl_create_entry(acl_p, &dst); + if (r < 0) + return -errno; + + r = acl_copy_entry(dst, i); + if (r < 0) + return -errno; + } + if (r < 0) + return -errno; + return 0; +} + +int acl_search_groups(const char *path, char ***ret_groups) { + _cleanup_strv_free_ char **g = NULL; + _cleanup_(acl_free) acl_t acl = NULL; + bool ret = false; + acl_entry_t entry; + int r; + + assert(path); + + acl = acl_get_file(path, ACL_TYPE_DEFAULT); + if (!acl) + return -errno; + + r = acl_get_entry(acl, ACL_FIRST_ENTRY, &entry); + for (;;) { + _cleanup_(acl_free_gid_tpp) gid_t *gid = NULL; + acl_tag_t tag; + + if (r < 0) + return -errno; + if (r == 0) + break; + + if (acl_get_tag_type(entry, &tag) < 0) + return -errno; + + if (tag != ACL_GROUP) + goto next; + + gid = acl_get_qualifier(entry); + if (!gid) + return -errno; + + if (in_gid(*gid) > 0) { + if (!ret_groups) + return true; + + ret = true; + } + + if (ret_groups) { + char *name; + + name = gid_to_name(*gid); + if (!name) + return -ENOMEM; + + r = strv_consume(&g, name); + if (r < 0) + return r; + } + + next: + r = acl_get_entry(acl, ACL_NEXT_ENTRY, &entry); + } + + if (ret_groups) { + *ret_groups = g; + g = NULL; + } + + return ret; +} + +int parse_acl(const char *text, acl_t *acl_access, acl_t *acl_default, bool want_mask) { + _cleanup_free_ char **a = NULL, **d = NULL; /* strings are not be freed */ + _cleanup_strv_free_ char **split; + char **entry; + int r = -EINVAL; + _cleanup_(acl_freep) acl_t a_acl = NULL, d_acl = NULL; + + split = strv_split(text, ","); + if (!split) + return -ENOMEM; + + STRV_FOREACH(entry, split) { + char *p; + + p = startswith(*entry, "default:"); + if (!p) + p = startswith(*entry, "d:"); + + if (p) + r = strv_push(&d, p); + else + r = strv_push(&a, *entry); + if (r < 0) + return r; + } + + if (!strv_isempty(a)) { + _cleanup_free_ char *join; + + join = strv_join(a, ","); + if (!join) + return -ENOMEM; + + a_acl = acl_from_text(join); + if (!a_acl) + return -errno; + + if (want_mask) { + r = calc_acl_mask_if_needed(&a_acl); + if (r < 0) + return r; + } + } + + if (!strv_isempty(d)) { + _cleanup_free_ char *join; + + join = strv_join(d, ","); + if (!join) + return -ENOMEM; + + d_acl = acl_from_text(join); + if (!d_acl) + return -errno; + + if (want_mask) { + r = calc_acl_mask_if_needed(&d_acl); + if (r < 0) + return r; + } + } + + *acl_access = a_acl; + *acl_default = d_acl; + a_acl = d_acl = NULL; + + return 0; +} + +static int acl_entry_equal(acl_entry_t a, acl_entry_t b) { + acl_tag_t tag_a, tag_b; + + if (acl_get_tag_type(a, &tag_a) < 0) + return -errno; + + if (acl_get_tag_type(b, &tag_b) < 0) + return -errno; + + if (tag_a != tag_b) + return false; + + switch (tag_a) { + case ACL_USER_OBJ: + case ACL_GROUP_OBJ: + case ACL_MASK: + case ACL_OTHER: + /* can have only one of those */ + return true; + case ACL_USER: { + _cleanup_(acl_free_uid_tpp) uid_t *uid_a = NULL, *uid_b = NULL; + + uid_a = acl_get_qualifier(a); + if (!uid_a) + return -errno; + + uid_b = acl_get_qualifier(b); + if (!uid_b) + return -errno; + + return *uid_a == *uid_b; + } + case ACL_GROUP: { + _cleanup_(acl_free_gid_tpp) gid_t *gid_a = NULL, *gid_b = NULL; + + gid_a = acl_get_qualifier(a); + if (!gid_a) + return -errno; + + gid_b = acl_get_qualifier(b); + if (!gid_b) + return -errno; + + return *gid_a == *gid_b; + } + default: + assert_not_reached("Unknown acl tag type"); + } +} + +static int find_acl_entry(acl_t acl, acl_entry_t entry, acl_entry_t *out) { + acl_entry_t i; + int r; + + for (r = acl_get_entry(acl, ACL_FIRST_ENTRY, &i); + r > 0; + r = acl_get_entry(acl, ACL_NEXT_ENTRY, &i)) { + + r = acl_entry_equal(i, entry); + if (r < 0) + return r; + if (r > 0) { + *out = i; + return 1; + } + } + if (r < 0) + return -errno; + return 0; +} + +int acls_for_file(const char *path, acl_type_t type, acl_t new, acl_t *acl) { + _cleanup_(acl_freep) acl_t old; + acl_entry_t i; + int r; + + old = acl_get_file(path, type); + if (!old) + return -errno; + + for (r = acl_get_entry(new, ACL_FIRST_ENTRY, &i); + r > 0; + r = acl_get_entry(new, ACL_NEXT_ENTRY, &i)) { + + acl_entry_t j; + + r = find_acl_entry(old, i, &j); + if (r < 0) + return r; + if (r == 0) + if (acl_create_entry(&old, &j) < 0) + return -errno; + + if (acl_copy_entry(j, i) < 0) + return -errno; + } + if (r < 0) + return -errno; + + *acl = old; + old = NULL; + return 0; +} + +int add_acls_for_user(int fd, uid_t uid) { + _cleanup_(acl_freep) acl_t acl = NULL; + acl_entry_t entry; + acl_permset_t permset; + int r; + + acl = acl_get_fd(fd); + if (!acl) + return -errno; + + r = acl_find_uid(acl, uid, &entry); + if (r <= 0) { + if (acl_create_entry(&acl, &entry) < 0 || + acl_set_tag_type(entry, ACL_USER) < 0 || + acl_set_qualifier(entry, &uid) < 0) + return -errno; + } + + /* We do not recalculate the mask unconditionally here, + * so that the fchmod() mask above stays intact. */ + if (acl_get_permset(entry, &permset) < 0 || + acl_add_perm(permset, ACL_READ) < 0) + return -errno; + + r = calc_acl_mask_if_needed(&acl); + if (r < 0) + return r; + + return acl_set_fd(fd, acl); +} |