Huw Davies | cb72d38 | 2016-06-27 15:02:46 -0400 | [diff] [blame^] | 1 | /* |
| 2 | * CALIPSO - Common Architecture Label IPv6 Security Option |
| 3 | * |
| 4 | * This is an implementation of the CALIPSO protocol as specified in |
| 5 | * RFC 5570. |
| 6 | * |
| 7 | * Authors: Paul Moore <paul.moore@hp.com> |
| 8 | * Huw Davies <huw@codeweavers.com> |
| 9 | * |
| 10 | */ |
| 11 | |
| 12 | /* (c) Copyright Hewlett-Packard Development Company, L.P., 2006, 2008 |
| 13 | * (c) Copyright Huw Davies <huw@codeweavers.com>, 2015 |
| 14 | * |
| 15 | * This program is free software; you can redistribute it and/or modify |
| 16 | * it under the terms of the GNU General Public License as published by |
| 17 | * the Free Software Foundation; either version 2 of the License, or |
| 18 | * (at your option) any later version. |
| 19 | * |
| 20 | * This program is distributed in the hope that it will be useful, |
| 21 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 22 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See |
| 23 | * the GNU General Public License for more details. |
| 24 | * |
| 25 | * You should have received a copy of the GNU General Public License |
| 26 | * along with this program; if not, see <http://www.gnu.org/licenses/>. |
| 27 | * |
| 28 | */ |
| 29 | |
| 30 | #include <linux/init.h> |
| 31 | #include <linux/types.h> |
| 32 | #include <linux/rcupdate.h> |
| 33 | #include <linux/list.h> |
| 34 | #include <linux/spinlock.h> |
| 35 | #include <linux/string.h> |
| 36 | #include <linux/jhash.h> |
| 37 | #include <linux/audit.h> |
| 38 | #include <linux/slab.h> |
| 39 | #include <net/ip.h> |
| 40 | #include <net/icmp.h> |
| 41 | #include <net/tcp.h> |
| 42 | #include <net/netlabel.h> |
| 43 | #include <net/calipso.h> |
| 44 | #include <linux/atomic.h> |
| 45 | #include <linux/bug.h> |
| 46 | #include <asm/unaligned.h> |
| 47 | |
| 48 | /* List of available DOI definitions */ |
| 49 | static DEFINE_SPINLOCK(calipso_doi_list_lock); |
| 50 | static LIST_HEAD(calipso_doi_list); |
| 51 | |
| 52 | /* DOI List Functions |
| 53 | */ |
| 54 | |
| 55 | /** |
| 56 | * calipso_doi_search - Searches for a DOI definition |
| 57 | * @doi: the DOI to search for |
| 58 | * |
| 59 | * Description: |
| 60 | * Search the DOI definition list for a DOI definition with a DOI value that |
| 61 | * matches @doi. The caller is responsible for calling rcu_read_[un]lock(). |
| 62 | * Returns a pointer to the DOI definition on success and NULL on failure. |
| 63 | */ |
| 64 | static struct calipso_doi *calipso_doi_search(u32 doi) |
| 65 | { |
| 66 | struct calipso_doi *iter; |
| 67 | |
| 68 | list_for_each_entry_rcu(iter, &calipso_doi_list, list) |
| 69 | if (iter->doi == doi && atomic_read(&iter->refcount)) |
| 70 | return iter; |
| 71 | return NULL; |
| 72 | } |
| 73 | |
| 74 | /** |
| 75 | * calipso_doi_add - Add a new DOI to the CALIPSO protocol engine |
| 76 | * @doi_def: the DOI structure |
| 77 | * @audit_info: NetLabel audit information |
| 78 | * |
| 79 | * Description: |
| 80 | * The caller defines a new DOI for use by the CALIPSO engine and calls this |
| 81 | * function to add it to the list of acceptable domains. The caller must |
| 82 | * ensure that the mapping table specified in @doi_def->map meets all of the |
| 83 | * requirements of the mapping type (see calipso.h for details). Returns |
| 84 | * zero on success and non-zero on failure. |
| 85 | * |
| 86 | */ |
| 87 | static int calipso_doi_add(struct calipso_doi *doi_def, |
| 88 | struct netlbl_audit *audit_info) |
| 89 | { |
| 90 | int ret_val = -EINVAL; |
| 91 | u32 doi; |
| 92 | u32 doi_type; |
| 93 | struct audit_buffer *audit_buf; |
| 94 | |
| 95 | doi = doi_def->doi; |
| 96 | doi_type = doi_def->type; |
| 97 | |
| 98 | if (doi_def->doi == CALIPSO_DOI_UNKNOWN) |
| 99 | goto doi_add_return; |
| 100 | |
| 101 | atomic_set(&doi_def->refcount, 1); |
| 102 | |
| 103 | spin_lock(&calipso_doi_list_lock); |
| 104 | if (calipso_doi_search(doi_def->doi)) { |
| 105 | spin_unlock(&calipso_doi_list_lock); |
| 106 | ret_val = -EEXIST; |
| 107 | goto doi_add_return; |
| 108 | } |
| 109 | list_add_tail_rcu(&doi_def->list, &calipso_doi_list); |
| 110 | spin_unlock(&calipso_doi_list_lock); |
| 111 | ret_val = 0; |
| 112 | |
| 113 | doi_add_return: |
| 114 | audit_buf = netlbl_audit_start(AUDIT_MAC_CALIPSO_ADD, audit_info); |
| 115 | if (audit_buf) { |
| 116 | const char *type_str; |
| 117 | |
| 118 | switch (doi_type) { |
| 119 | case CALIPSO_MAP_PASS: |
| 120 | type_str = "pass"; |
| 121 | break; |
| 122 | default: |
| 123 | type_str = "(unknown)"; |
| 124 | } |
| 125 | audit_log_format(audit_buf, |
| 126 | " calipso_doi=%u calipso_type=%s res=%u", |
| 127 | doi, type_str, ret_val == 0 ? 1 : 0); |
| 128 | audit_log_end(audit_buf); |
| 129 | } |
| 130 | |
| 131 | return ret_val; |
| 132 | } |
| 133 | |
| 134 | /** |
| 135 | * calipso_doi_free - Frees a DOI definition |
| 136 | * @doi_def: the DOI definition |
| 137 | * |
| 138 | * Description: |
| 139 | * This function frees all of the memory associated with a DOI definition. |
| 140 | * |
| 141 | */ |
| 142 | static void calipso_doi_free(struct calipso_doi *doi_def) |
| 143 | { |
| 144 | kfree(doi_def); |
| 145 | } |
| 146 | |
| 147 | static const struct netlbl_calipso_ops ops = { |
| 148 | .doi_add = calipso_doi_add, |
| 149 | .doi_free = calipso_doi_free, |
| 150 | }; |
| 151 | |
| 152 | /** |
| 153 | * calipso_init - Initialize the CALIPSO module |
| 154 | * |
| 155 | * Description: |
| 156 | * Initialize the CALIPSO module and prepare it for use. Returns zero on |
| 157 | * success and negative values on failure. |
| 158 | * |
| 159 | */ |
| 160 | int __init calipso_init(void) |
| 161 | { |
| 162 | netlbl_calipso_ops_register(&ops); |
| 163 | return 0; |
| 164 | } |
| 165 | |
| 166 | void calipso_exit(void) |
| 167 | { |
| 168 | netlbl_calipso_ops_register(NULL); |
| 169 | } |