1 /***************************************************************************
2 * Copyright (c) 2024 Microsoft Corporation
3 *
4 * This program and the accompanying materials are made available under the
5 * terms of the MIT License which is available at
6 * https://opensource.org/licenses/MIT.
7 *
8 * SPDX-License-Identifier: MIT
9 **************************************************************************/
10
11
12 /**************************************************************************/
13 /**************************************************************************/
14 /** */
15 /** NetX Component */
16 /** */
17 /** Address Resolution Protocol (ARP) */
18 /** */
19 /**************************************************************************/
20 /**************************************************************************/
21
22 #define NX_SOURCE_CODE
23
24
25 /* Include necessary system files. */
26
27 #include "nx_api.h"
28 #include "nx_arp.h"
29
30
31 /**************************************************************************/
32 /* */
33 /* FUNCTION RELEASE */
34 /* */
35 /* _nx_arp_enable PORTABLE C */
36 /* 6.1 */
37 /* AUTHOR */
38 /* */
39 /* Yuxin Zhou, Microsoft Corporation */
40 /* */
41 /* DESCRIPTION */
42 /* */
43 /* This function enables the ARP management component for the */
44 /* specified IP instance. */
45 /* */
46 /* INPUT */
47 /* */
48 /* ip_ptr IP instance pointer */
49 /* arp_cache_memory Start of ARP cache memory */
50 /* arp_cache_size Size in bytes of cache memory */
51 /* memset Set the memory */
52 /* */
53 /* OUTPUT */
54 /* */
55 /* status Completion status */
56 /* */
57 /* CALLS */
58 /* */
59 /* None */
60 /* */
61 /* CALLED BY */
62 /* */
63 /* Application Code */
64 /* */
65 /* RELEASE HISTORY */
66 /* */
67 /* DATE NAME DESCRIPTION */
68 /* */
69 /* 05-19-2020 Yuxin Zhou Initial Version 6.0 */
70 /* 09-30-2020 Yuxin Zhou Modified comment(s), */
71 /* resulting in version 6.1 */
72 /* */
73 /**************************************************************************/
_nx_arp_enable(NX_IP * ip_ptr,VOID * arp_cache_memory,ULONG arp_cache_size)74 UINT _nx_arp_enable(NX_IP *ip_ptr, VOID *arp_cache_memory, ULONG arp_cache_size)
75 {
76
77 #ifndef NX_DISABLE_IPV4
78 ULONG i;
79 ULONG arp_entries;
80 NX_ARP *entry_ptr;
81
82
83 /* If trace is enabled, insert this event into the trace buffer. */
84 NX_TRACE_IN_LINE_INSERT(NX_TRACE_ARP_ENABLE, ip_ptr, arp_cache_memory, arp_cache_size, 0, NX_TRACE_ARP_EVENTS, 0, 0);
85
86 /* Clear the entire ARP cache. */
87 memset((void *)arp_cache_memory, 0, arp_cache_size);
88
89 /* Pickup starting address of ARP entry array. */
90 entry_ptr = (NX_ARP *)arp_cache_memory;
91
92 /* Determine how many ARP entries will fit in this cache area. */
93 arp_entries = arp_cache_size / sizeof(NX_ARP);
94
95 /* Initialize the forward pointers of available ARP entries. */
96 for (i = 0; i < (arp_entries - 1); i++)
97 {
98 /* Setup each entry to point to the next entry. */
99 entry_ptr -> nx_arp_pool_next = entry_ptr + 1;
100 entry_ptr++;
101 }
102
103 /* The entry now points to the last entry in the ARP array. Set its
104 next pointer to the first entry. */
105 entry_ptr -> nx_arp_pool_next = (NX_ARP *)arp_cache_memory;
106
107 /* Initialize the backward pointers of available ARP entries. */
108 for (i = 0; i < (arp_entries - 1); i++)
109 {
110 /* Setup each entry to point to the previous entry. */
111 entry_ptr -> nx_arp_pool_previous = entry_ptr - 1;
112 entry_ptr--;
113 }
114
115 /* The entry now points to the first entry, set the previous pointer
116 to the last entry. */
117 entry_ptr -> nx_arp_pool_previous = (entry_ptr + (arp_entries - 1));
118
119 /* At this point, everything is okay in the ARP enable call.. populate the
120 information in the IP structure. */
121
122 /* Setup the list head pointers in the IP instance. At first all ARP
123 entries are associated with the dynamic ARP list. The static ARP list
124 is NULL until static ARP entry calls are made. */
125 ip_ptr -> nx_ip_arp_static_list = NX_NULL;
126 ip_ptr -> nx_ip_arp_dynamic_list = (NX_ARP *)arp_cache_memory;
127
128 /* Store the initial ARP cache information in the IP control block. */
129 ip_ptr -> nx_ip_arp_cache_memory = arp_cache_memory;
130 ip_ptr -> nx_ip_arp_total_entries = arp_entries;
131
132 /* Setup the ARP periodic update routine. */
133 ip_ptr -> nx_ip_arp_periodic_update = _nx_arp_periodic_update;
134
135 /* Setup the ARP queue process routine. */
136 ip_ptr -> nx_ip_arp_queue_process = _nx_arp_queue_process;
137
138 /* Setup the ARP send packet routine. */
139 ip_ptr -> nx_ip_arp_packet_send = _nx_arp_packet_send;
140
141 /* Setup the ARP allocate service request pointer. */
142 ip_ptr -> nx_ip_arp_allocate = _nx_arp_entry_allocate;
143
144 /* Return successful completion. */
145 return(NX_SUCCESS);
146 #else /* NX_DISABLE_IPV4 */
147 NX_PARAMETER_NOT_USED(ip_ptr);
148 NX_PARAMETER_NOT_USED(arp_cache_memory);
149 NX_PARAMETER_NOT_USED(arp_cache_size);
150
151 return(NX_NOT_SUPPORTED);
152 #endif /* !NX_DISABLE_IPV4 */
153 }
154
155
