bsd/net/net_str_id.c

   1 /*
   2  * Copyright (c) 2008 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/kalloc.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 #include "net/net_str_id.h"
  43
  44 #define NET_ID_STR_ENTRY_SIZE(__str) \
  45         ((size_t)&(((struct net_str_id_entry*)0)->nsi_string[0]) + \
  46         strlen(__str) + 1)
  47
  48 #define FIRST_NET_STR_ID                                1000
  49 static SLIST_HEAD(,net_str_id_entry)    net_str_id_list = {NULL};
  50 static lck_mtx_t                                                *net_str_id_lock = NULL;
  51
  52 static u_int32_t nsi_kind_next[NSI_MAX_KIND] = { FIRST_NET_STR_ID, FIRST_NET_STR_ID, FIRST_NET_STR_ID };
  53 static u_int32_t nsi_next_id = FIRST_NET_STR_ID;
  54
  55 #if NETMIBS
  56
  57 extern int sysctl_if_family_ids SYSCTL_HANDLER_ARGS;
  58
  59 SYSCTL_DECL(_net_link_generic_system);
  60
  61 SYSCTL_PROC(_net_link_generic_system, OID_AUTO, if_family_ids, CTLTYPE_STRUCT | CTLFLAG_RD | CTLFLAG_LOCKED,
  62         0, 0, sysctl_if_family_ids, "S, if_family_id", "Interface Family ID table");
  63
  64 #endif /* NETMIBS */
  65
  66
  67 __private_extern__ void
  68 net_str_id_init(void)
  69 {
  70         lck_grp_attr_t  *grp_attrib = NULL;
  71         lck_attr_t              *lck_attrb = NULL;
  72         lck_grp_t               *lck_group = NULL;
  73
  74         grp_attrib = lck_grp_attr_alloc_init();
  75         lck_group = lck_grp_alloc_init("mbuf_tag_allocate_id", grp_attrib);
  76         lck_grp_attr_free(grp_attrib);
  77         lck_attrb = lck_attr_alloc_init();
  78
  79         net_str_id_lock = lck_mtx_alloc_init(lck_group, lck_attrb);
  80
  81         lck_grp_free(lck_group);
  82         lck_attr_free(lck_attrb);
  83 }
  84
  85 __private_extern__ void
  86 net_str_id_first_last(u_int32_t *first, u_int32_t *last, u_int32_t kind)
  87 {
  88         *first = FIRST_NET_STR_ID;
  89
  90         switch (kind) {
  91                 case NSI_MBUF_TAG:
  92                 case NSI_VENDOR_CODE:
  93                 case NSI_IF_FAM_ID:
  94                         *last = nsi_kind_next[kind] - 1;
  95                         break;
  96                 default:
  97                         *last = FIRST_NET_STR_ID - 1;
  98                         break;
  99         }
 100 }
 101
 102 __private_extern__ errno_t
 103 net_str_id_find_internal(const char     *string, u_int32_t *out_id,
 104                                                   u_int32_t     kind, int create)
 105 {
 106         struct net_str_id_entry                 *entry = NULL;
 107
 108
 109         if (string == NULL || out_id == NULL || kind >= NSI_MAX_KIND)
 110                 return EINVAL;
 111
 112         *out_id = 0;
 113
 114         /* Look for an existing entry */
 115         lck_mtx_lock(net_str_id_lock);
 116         SLIST_FOREACH(entry, &net_str_id_list, nsi_next) {
 117                 if (strcmp(string, entry->nsi_string) == 0) {
 118                         break;
 119                 }
 120         }
 121
 122         if (entry == NULL) {
 123                 if (create == 0) {
 124                         lck_mtx_unlock(net_str_id_lock);
 125                         return ENOENT;
 126                 }
 127
 128                 entry = kalloc(NET_ID_STR_ENTRY_SIZE(string));
 129                 if (entry == NULL) {
 130                         lck_mtx_unlock(net_str_id_lock);
 131                         return ENOMEM;
 132                 }
 133
 134                 strlcpy(entry->nsi_string, string, strlen(string) + 1);
 135                 entry->nsi_flags = (1 << kind);
 136                 entry->nsi_id = nsi_next_id++;
 137                 nsi_kind_next[kind] = nsi_next_id;
 138                 SLIST_INSERT_HEAD(&net_str_id_list, entry, nsi_next);
 139         } else if ((entry->nsi_flags & (1 << kind)) == 0) {
 140                 if (create == 0) {
 141                         lck_mtx_unlock(net_str_id_lock);
 142                         return ENOENT;
 143                 }
 144                 entry->nsi_flags |= (1 << kind);
 145                 if (entry->nsi_id >= nsi_kind_next[kind])
 146                         nsi_kind_next[kind] = entry->nsi_id + 1;
 147         }
 148         lck_mtx_unlock(net_str_id_lock);
 149
 150         *out_id = entry->nsi_id;
 151
 152         return 0;
 153 }
 154
 155
 156 #if NETMIBS
 157
 158 #define ROUNDUP32(a) \
 159         ((a) > 0 ? (1 + (((a) - 1) | (sizeof(uint32_t) - 1))) : sizeof(uint32_t))
 160
 161 int
 162 sysctl_if_family_ids SYSCTL_HANDLER_ARGS /* XXX bad syntax! */
 163 {
 164 #pragma unused(oidp)
 165 #pragma unused(arg1)
 166 #pragma unused(arg2)
 167         errno_t error = 0;
 168         struct net_str_id_entry *entry = NULL;
 169         struct if_family_id *iffmid = NULL;
 170         size_t max_size = 0;
 171
 172         lck_mtx_lock(net_str_id_lock);
 173         SLIST_FOREACH(entry, &net_str_id_list, nsi_next) {
 174                 size_t str_size;
 175                 size_t iffmid_size;
 176
 177                 if ((entry->nsi_flags & (1 << NSI_IF_FAM_ID)) == 0)
 178                         continue;
 179
 180                 str_size = strlen(entry->nsi_string) + 1;
 181                 iffmid_size = ROUNDUP32(offsetof(struct net_str_id_entry, nsi_string) + str_size);
 182
 183                 if (iffmid_size > max_size) {
 184                         if (iffmid)
 185                                 _FREE(iffmid, M_TEMP);
 186                         iffmid = _MALLOC(iffmid_size, M_TEMP, M_WAITOK);
 187                         if (iffmid == NULL) {
 188                                 lck_mtx_unlock(net_str_id_lock);
 189                                 error = ENOMEM;
 190                                 goto done;
 191                         }
 192                         max_size = iffmid_size;
 193                 }
 194
 195                 bzero(iffmid, iffmid_size);
 196                 iffmid->iffmid_len = iffmid_size;
 197                 iffmid->iffmid_id = entry->nsi_id;
 198                 strlcpy(iffmid->iffmid_str, entry->nsi_string, str_size);
 199         error = SYSCTL_OUT(req, iffmid, iffmid_size);
 200         if (error) {
 201                         lck_mtx_unlock(net_str_id_lock);
 202                         goto done;
 203         }
 204
 205         }
 206         lck_mtx_unlock(net_str_id_lock);
 207
 208 done:
 209         if (iffmid)
 210                 _FREE(iffmid, M_TEMP);
 211         return error;
 212 }
 213
 214 #endif /* NETMIBS */
 215