1 /**
2 * @file
3 * SNMP scalar node support implementation.
4 */
5
6 /*
7 * Copyright (c) 2001-2004 Swedish Institute of Computer Science.
8 * All rights reserved.
9 *
10 * Redistribution and use in source and binary forms, with or without modification,
11 * are permitted provided that the following conditions are met:
12 *
13 * 1. Redistributions of source code must retain the above copyright notice,
14 * this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright notice,
16 * this list of conditions and the following disclaimer in the documentation
17 * and/or other materials provided with the distribution.
18 * 3. The name of the author may not be used to endorse or promote products
19 * derived from this software without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
22 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
23 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
24 * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
25 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
26 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
29 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
30 * OF SUCH DAMAGE.
31 *
32 * This file is part of the lwIP TCP/IP stack.
33 *
34 * Author: Martin Hentschel <info@cl-soft.de>
35 *
36 */
37
38 #include "lwip/apps/snmp_opts.h"
39
40 #if LWIP_SNMP /* don't build if not configured for use in lwipopts.h */
41
42 #include "lwip/apps/snmp_scalar.h"
43 #include "lwip/apps/snmp_core.h"
44
45 static s16_t snmp_scalar_array_get_value(struct snmp_node_instance *instance, void *value);
46 static snmp_err_t snmp_scalar_array_set_test(struct snmp_node_instance *instance, u16_t value_len, void *value);
47 static snmp_err_t snmp_scalar_array_set_value(struct snmp_node_instance *instance, u16_t value_len, void *value);
48
49 snmp_err_t
snmp_scalar_get_instance(const u32_t * root_oid,u8_t root_oid_len,struct snmp_node_instance * instance)50 snmp_scalar_get_instance(const u32_t *root_oid, u8_t root_oid_len, struct snmp_node_instance *instance)
51 {
52 const struct snmp_scalar_node *scalar_node = (const struct snmp_scalar_node *)(const void *)instance->node;
53
54 LWIP_UNUSED_ARG(root_oid);
55 LWIP_UNUSED_ARG(root_oid_len);
56
57 /* scalar only has one dedicated instance: .0 */
58 if ((instance->instance_oid.len != 1) || (instance->instance_oid.id[0] != 0)) {
59 return SNMP_ERR_NOSUCHINSTANCE;
60 }
61
62 instance->access = scalar_node->access;
63 instance->asn1_type = scalar_node->asn1_type;
64 instance->get_value = scalar_node->get_value;
65 instance->set_test = scalar_node->set_test;
66 instance->set_value = scalar_node->set_value;
67 return SNMP_ERR_NOERROR;
68 }
69
70 snmp_err_t
snmp_scalar_get_next_instance(const u32_t * root_oid,u8_t root_oid_len,struct snmp_node_instance * instance)71 snmp_scalar_get_next_instance(const u32_t *root_oid, u8_t root_oid_len, struct snmp_node_instance *instance)
72 {
73 /* because our only instance is .0 we can only return a next instance if no instance oid is passed */
74 if (instance->instance_oid.len == 0) {
75 instance->instance_oid.len = 1;
76 instance->instance_oid.id[0] = 0;
77
78 return snmp_scalar_get_instance(root_oid, root_oid_len, instance);
79 }
80
81 return SNMP_ERR_NOSUCHINSTANCE;
82 }
83
84
85 snmp_err_t
snmp_scalar_array_get_instance(const u32_t * root_oid,u8_t root_oid_len,struct snmp_node_instance * instance)86 snmp_scalar_array_get_instance(const u32_t *root_oid, u8_t root_oid_len, struct snmp_node_instance *instance)
87 {
88 LWIP_UNUSED_ARG(root_oid);
89 LWIP_UNUSED_ARG(root_oid_len);
90
91 if ((instance->instance_oid.len == 2) && (instance->instance_oid.id[1] == 0)) {
92 const struct snmp_scalar_array_node *array_node = (const struct snmp_scalar_array_node *)(const void *)instance->node;
93 const struct snmp_scalar_array_node_def *array_node_def = array_node->array_nodes;
94 u32_t i = 0;
95
96 while (i < array_node->array_node_count) {
97 if (array_node_def->oid == instance->instance_oid.id[0]) {
98 break;
99 }
100
101 array_node_def++;
102 i++;
103 }
104
105 if (i < array_node->array_node_count) {
106 instance->access = array_node_def->access;
107 instance->asn1_type = array_node_def->asn1_type;
108 instance->get_value = snmp_scalar_array_get_value;
109 instance->set_test = snmp_scalar_array_set_test;
110 instance->set_value = snmp_scalar_array_set_value;
111 instance->reference.const_ptr = array_node_def;
112
113 return SNMP_ERR_NOERROR;
114 }
115 }
116
117 return SNMP_ERR_NOSUCHINSTANCE;
118 }
119
120 snmp_err_t
snmp_scalar_array_get_next_instance(const u32_t * root_oid,u8_t root_oid_len,struct snmp_node_instance * instance)121 snmp_scalar_array_get_next_instance(const u32_t *root_oid, u8_t root_oid_len, struct snmp_node_instance *instance)
122 {
123 const struct snmp_scalar_array_node *array_node = (const struct snmp_scalar_array_node *)(const void *)instance->node;
124 const struct snmp_scalar_array_node_def *array_node_def = array_node->array_nodes;
125 const struct snmp_scalar_array_node_def *result = NULL;
126
127 LWIP_UNUSED_ARG(root_oid);
128 LWIP_UNUSED_ARG(root_oid_len);
129
130 if ((instance->instance_oid.len == 0) && (array_node->array_node_count > 0)) {
131 /* return node with lowest OID */
132 u16_t i = 0;
133
134 result = array_node_def;
135 array_node_def++;
136
137 for (i = 1; i < array_node->array_node_count; i++) {
138 if (array_node_def->oid < result->oid) {
139 result = array_node_def;
140 }
141 array_node_def++;
142 }
143 } else if (instance->instance_oid.len >= 1) {
144 if (instance->instance_oid.len == 1) {
145 /* if we have the requested OID we return its instance, otherwise we search for the next available */
146 u16_t i = 0;
147 while (i < array_node->array_node_count) {
148 if (array_node_def->oid == instance->instance_oid.id[0]) {
149 result = array_node_def;
150 break;
151 }
152
153 array_node_def++;
154 i++;
155 }
156 }
157 if (result == NULL) {
158 u32_t oid_dist = 0xFFFFFFFFUL;
159 u16_t i = 0;
160 array_node_def = array_node->array_nodes; /* may be already at the end when if case before was executed without result -> reinitialize to start */
161 while (i < array_node->array_node_count) {
162 if ((array_node_def->oid > instance->instance_oid.id[0]) &&
163 ((u32_t)(array_node_def->oid - instance->instance_oid.id[0]) < oid_dist)) {
164 result = array_node_def;
165 oid_dist = array_node_def->oid - instance->instance_oid.id[0];
166 }
167
168 array_node_def++;
169 i++;
170 }
171 }
172 }
173
174 if (result == NULL) {
175 /* nothing to return */
176 return SNMP_ERR_NOSUCHINSTANCE;
177 }
178
179 instance->instance_oid.len = 2;
180 instance->instance_oid.id[0] = result->oid;
181 instance->instance_oid.id[1] = 0;
182
183 instance->access = result->access;
184 instance->asn1_type = result->asn1_type;
185 instance->get_value = snmp_scalar_array_get_value;
186 instance->set_test = snmp_scalar_array_set_test;
187 instance->set_value = snmp_scalar_array_set_value;
188 instance->reference.const_ptr = result;
189
190 return SNMP_ERR_NOERROR;
191 }
192
193 static s16_t
snmp_scalar_array_get_value(struct snmp_node_instance * instance,void * value)194 snmp_scalar_array_get_value(struct snmp_node_instance *instance, void *value)
195 {
196 s16_t result = -1;
197 const struct snmp_scalar_array_node *array_node = (const struct snmp_scalar_array_node *)(const void *)instance->node;
198 const struct snmp_scalar_array_node_def *array_node_def = (const struct snmp_scalar_array_node_def *)instance->reference.const_ptr;
199
200 if (array_node->get_value != NULL) {
201 result = array_node->get_value(array_node_def, value);
202 }
203 return result;
204 }
205
206 static snmp_err_t
snmp_scalar_array_set_test(struct snmp_node_instance * instance,u16_t value_len,void * value)207 snmp_scalar_array_set_test(struct snmp_node_instance *instance, u16_t value_len, void *value)
208 {
209 snmp_err_t result = SNMP_ERR_NOTWRITABLE;
210 const struct snmp_scalar_array_node *array_node = (const struct snmp_scalar_array_node *)(const void *)instance->node;
211 const struct snmp_scalar_array_node_def *array_node_def = (const struct snmp_scalar_array_node_def *)instance->reference.const_ptr;
212
213 if (array_node->set_test != NULL) {
214 result = array_node->set_test(array_node_def, value_len, value);
215 }
216 return result;
217 }
218
219 static snmp_err_t
snmp_scalar_array_set_value(struct snmp_node_instance * instance,u16_t value_len,void * value)220 snmp_scalar_array_set_value(struct snmp_node_instance *instance, u16_t value_len, void *value)
221 {
222 snmp_err_t result = SNMP_ERR_NOTWRITABLE;
223 const struct snmp_scalar_array_node *array_node = (const struct snmp_scalar_array_node *)(const void *)instance->node;
224 const struct snmp_scalar_array_node_def *array_node_def = (const struct snmp_scalar_array_node_def *)instance->reference.const_ptr;
225
226 if (array_node->set_value != NULL) {
227 result = array_node->set_value(array_node_def, value_len, value);
228 }
229 return result;
230 }
231
232 #endif /* LWIP_SNMP */
233