1 /*
2 * Copyright (c) 2008-2021 Apple Inc. All rights reserved.
3 *
4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5 *
6 * This file contains Original Code and/or Modifications of Original Code
7 * as defined in and that are subject to the Apple Public Source License
8 * Version 2.0 (the 'License'). You may not use this file except in
9 * compliance with the License. The rights granted to you under the License
10 * may not be used to create, or enable the creation or redistribution of,
11 * unlawful or unlicensed copies of an Apple operating system, or to
12 * circumvent, violate, or enable the circumvention or violation of, any
13 * terms of an Apple operating system software license agreement.
14 *
15 * Please obtain a copy of the License at
16 * http://www.opensource.apple.com/apsl/ and read it before using this file.
17 *
18 * The Original Code and all software distributed under the License are
19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23 * Please see the License for the specific language governing rights and
24 * limitations under the License.
25 *
26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27 */
28
29 #include <sys/types.h>
30 #include <kern/locks.h>
31 #include <kern/zalloc.h>
32 #include <sys/errno.h>
33 #include <sys/sysctl.h>
34 #include <sys/malloc.h>
35 #include <sys/socket.h>
36 #include <libkern/OSAtomic.h>
37 #include <libkern/libkern.h>
38 #include <net/if.h>
39 #include <net/if_mib.h>
40 #include <string.h>
41
42 // TODO: -fbounds-safety increases the alignment and we have
43 // no control over the alignment. (rdar://118519573)
44 #pragma clang diagnostic ignored "-Wcast-align"
45 #include "net/net_str_id.h"
46
47 #define NET_ID_STR_MAX_LEN 2048
48
49 #define FIRST_NET_STR_ID 1000
50 static SLIST_HEAD(, net_str_id_entry) net_str_id_list = {NULL};
51 static LCK_GRP_DECLARE(net_str_id_grp, "mbuf_tag_allocate_id");
52 static LCK_MTX_DECLARE(net_str_id_lock, &net_str_id_grp);
53
54 static u_int32_t nsi_kind_next[NSI_MAX_KIND] = { FIRST_NET_STR_ID, FIRST_NET_STR_ID, FIRST_NET_STR_ID };
55 static u_int32_t nsi_next_id = FIRST_NET_STR_ID;
56
57 __private_extern__ void
net_str_id_first_last(u_int32_t * first,u_int32_t * last,u_int32_t kind)58 net_str_id_first_last(u_int32_t *first, u_int32_t *last, u_int32_t kind)
59 {
60 *first = FIRST_NET_STR_ID;
61
62 switch (kind) {
63 case NSI_MBUF_TAG:
64 case NSI_VENDOR_CODE:
65 case NSI_IF_FAM_ID:
66 *last = nsi_kind_next[kind] - 1;
67 break;
68 default:
69 *last = FIRST_NET_STR_ID - 1;
70 break;
71 }
72 }
73
74 __private_extern__ errno_t
net_str_id_find_internal(const char * string,u_int32_t * out_id,u_int32_t kind,int create)75 net_str_id_find_internal(const char *string, u_int32_t *out_id,
76 u_int32_t kind, int create)
77 {
78 struct net_str_id_entry *entry = NULL;
79
80
81 if (string == NULL || out_id == NULL || kind >= NSI_MAX_KIND) {
82 return EINVAL;
83 }
84 if (strlen(string) > NET_ID_STR_MAX_LEN) {
85 return EINVAL;
86 }
87
88 *out_id = 0;
89
90 /* Look for an existing entry */
91 lck_mtx_lock(&net_str_id_lock);
92 SLIST_FOREACH(entry, &net_str_id_list, nsi_next) {
93 if (strlcmp(entry->nsi_string, string, entry->nsi_length) == 0) {
94 break;
95 }
96 }
97
98 if (entry == NULL) {
99 if (create == 0) {
100 lck_mtx_unlock(&net_str_id_lock);
101 return ENOENT;
102 }
103
104 const uint32_t string_length = (uint32_t)strlen(string) + 1;
105 entry = zalloc_permanent(sizeof(*entry) + string_length,
106 ZALIGN_PTR);
107 if (entry == NULL) {
108 lck_mtx_unlock(&net_str_id_lock);
109 return ENOMEM;
110 }
111
112 strlcpy(entry->nsi_string, string, string_length);
113 entry->nsi_length = string_length;
114 entry->nsi_flags = (1 << kind);
115 entry->nsi_id = nsi_next_id++;
116 nsi_kind_next[kind] = nsi_next_id;
117 SLIST_INSERT_HEAD(&net_str_id_list, entry, nsi_next);
118 } else if ((entry->nsi_flags & (1 << kind)) == 0) {
119 if (create == 0) {
120 lck_mtx_unlock(&net_str_id_lock);
121 return ENOENT;
122 }
123 entry->nsi_flags |= (1 << kind);
124 if (entry->nsi_id >= nsi_kind_next[kind]) {
125 nsi_kind_next[kind] = entry->nsi_id + 1;
126 }
127 }
128 lck_mtx_unlock(&net_str_id_lock);
129
130 *out_id = entry->nsi_id;
131
132 return 0;
133 }
134