1 /**************************************************************************/
2 /* */
3 /* Copyright (c) Microsoft Corporation. All rights reserved. */
4 /* */
5 /* This software is licensed under the Microsoft Software License */
6 /* Terms for Microsoft Azure RTOS. Full text of the license can be */
7 /* found in the LICENSE file at https://aka.ms/AzureRTOS_EULA */
8 /* and in the root directory of this software. */
9 /* */
10 /**************************************************************************/
11
12
13 /**************************************************************************/
14 /**************************************************************************/
15 /** */
16 /** NetX Component */
17 /** */
18 /** Address Resolution Protocol (ARP) */
19 /** */
20 /**************************************************************************/
21 /**************************************************************************/
22
23 #define NX_SOURCE_CODE
24
25
26 /* Include necessary system files. */
27
28 #include "nx_api.h"
29 #include "nx_arp.h"
30 #include "nx_packet.h"
31
32 #ifndef NX_DISABLE_IPV4
33 /**************************************************************************/
34 /* */
35 /* FUNCTION RELEASE */
36 /* */
37 /* _nx_arp_packet_send PORTABLE C */
38 /* 6.1 */
39 /* AUTHOR */
40 /* */
41 /* Yuxin Zhou, Microsoft Corporation */
42 /* */
43 /* DESCRIPTION */
44 /* */
45 /* This function builds an ARP packet and calls the associated driver */
46 /* to send it out on the specified network interface. */
47 /* */
48 /* INPUT */
49 /* */
50 /* ip_ptr Pointer to IP instance */
51 /* destination_ip Destination IP address */
52 /* nx_interface Interface to transmit out */
53 /* */
54 /* OUTPUT */
55 /* */
56 /* None */
57 /* */
58 /* CALLS */
59 /* */
60 /* _nx_packet_allocate Allocate a packet for the */
61 /* ARP request */
62 /* [ip_link_driver] User supplied link driver */
63 /* */
64 /* CALLED BY */
65 /* */
66 /* NetX Source Code */
67 /* */
68 /* RELEASE HISTORY */
69 /* */
70 /* DATE NAME DESCRIPTION */
71 /* */
72 /* 05-19-2020 Yuxin Zhou Initial Version 6.0 */
73 /* 09-30-2020 Yuxin Zhou Modified comment(s), */
74 /* resulting in version 6.1 */
75 /* */
76 /**************************************************************************/
_nx_arp_packet_send(NX_IP * ip_ptr,ULONG destination_ip,NX_INTERFACE * nx_interface)77 VOID _nx_arp_packet_send(NX_IP *ip_ptr, ULONG destination_ip, NX_INTERFACE *nx_interface)
78 {
79
80 NX_PACKET *request_ptr;
81 ULONG *message_ptr;
82 NX_IP_DRIVER driver_request;
83
84 /* nx_interface must not be NX_NULL. */
85 NX_ASSERT(nx_interface != NX_NULL);
86
87 /* Allocate a packet to build the ARP message in. */
88 #ifdef NX_ENABLE_DUAL_PACKET_POOL
89 /* Allocate from auxiliary packet pool first. */
90 if (_nx_packet_allocate(ip_ptr -> nx_ip_auxiliary_packet_pool, &request_ptr, (NX_PHYSICAL_HEADER + NX_ARP_MESSAGE_SIZE), NX_NO_WAIT))
91 {
92 if (ip_ptr -> nx_ip_auxiliary_packet_pool != ip_ptr -> nx_ip_default_packet_pool)
93 #endif /* NX_ENABLE_DUAL_PACKET_POOL */
94 {
95 if (_nx_packet_allocate(ip_ptr -> nx_ip_default_packet_pool, &request_ptr, (NX_PHYSICAL_HEADER + NX_ARP_MESSAGE_SIZE), NX_NO_WAIT))
96 {
97
98 /* Error getting packet, so just get out! */
99 return;
100 }
101 }
102 #ifdef NX_ENABLE_DUAL_PACKET_POOL
103 else
104 {
105
106 /* Error getting packet, so just get out! */
107 return;
108 }
109 }
110 #endif /* NX_ENABLE_DUAL_PACKET_POOL */
111
112 /* Add debug information. */
113 NX_PACKET_DEBUG(__FILE__, __LINE__, request_ptr);
114
115 /* Stamp the packet with the outgoing interface information. */
116 /*lint -e{644} suppress variable might not be initialized, since "request_ptr" was initialized in _nx_packet_allocate. */
117 request_ptr -> nx_packet_address.nx_packet_interface_ptr = nx_interface;
118
119 #ifndef NX_DISABLE_ARP_INFO
120 /* Increment the ARP requests sent count. */
121 ip_ptr -> nx_ip_arp_requests_sent++;
122 #endif
123
124 /* If trace is enabled, insert this event into the trace buffer. */
125 NX_TRACE_IN_LINE_INSERT(NX_TRACE_INTERNAL_ARP_REQUEST_SEND, ip_ptr, destination_ip, request_ptr, 0, NX_TRACE_INTERNAL_EVENTS, 0, 0);
126
127 /* Build the ARP request packet. */
128
129 /* Setup the size of the ARP message. */
130 request_ptr -> nx_packet_length = NX_ARP_MESSAGE_SIZE;
131
132 /* Setup the prepend pointer. */
133 request_ptr -> nx_packet_prepend_ptr -= NX_ARP_MESSAGE_SIZE;
134
135 /* Setup the pointer to the message area. */
136 /*lint -e{927} -e{826} suppress cast of pointer to pointer, since it is necessary */
137 message_ptr = (ULONG *)request_ptr -> nx_packet_prepend_ptr;
138
139 /* Write the Hardware type into the message. */
140 *message_ptr = (ULONG)(NX_ARP_HARDWARE_TYPE << 16) | (NX_ARP_PROTOCOL_TYPE);
141 *(message_ptr + 1) = (ULONG)(NX_ARP_HARDWARE_SIZE << 24) | (NX_ARP_PROTOCOL_SIZE << 16) |
142 NX_ARP_OPTION_REQUEST;
143
144 /*lint -e{613} suppress possible use of null pointer, since nx_interface must not be NULL. */
145 *(message_ptr + 2) = (ULONG)(nx_interface -> nx_interface_physical_address_msw << 16) |
146 (nx_interface -> nx_interface_physical_address_lsw >> 16);
147 *(message_ptr + 3) = (ULONG)(nx_interface -> nx_interface_physical_address_lsw << 16) |
148 (nx_interface -> nx_interface_ip_address >> 16);
149 *(message_ptr + 4) = (ULONG)(nx_interface -> nx_interface_ip_address << 16);
150 *(message_ptr + 5) = (ULONG)0;
151 *(message_ptr + 6) = (ULONG)destination_ip;
152
153 /* Endian swapping logic. If NX_LITTLE_ENDIAN is specified, these macros will
154 swap the endian of the ARP message. */
155 NX_CHANGE_ULONG_ENDIAN(*(message_ptr));
156 NX_CHANGE_ULONG_ENDIAN(*(message_ptr + 1));
157 NX_CHANGE_ULONG_ENDIAN(*(message_ptr + 2));
158 NX_CHANGE_ULONG_ENDIAN(*(message_ptr + 3));
159 NX_CHANGE_ULONG_ENDIAN(*(message_ptr + 4));
160 NX_CHANGE_ULONG_ENDIAN(*(message_ptr + 5));
161 NX_CHANGE_ULONG_ENDIAN(*(message_ptr + 6));
162
163 /* Set up the driver request. */
164 driver_request.nx_ip_driver_ptr = ip_ptr;
165 driver_request.nx_ip_driver_command = NX_LINK_ARP_SEND;
166 driver_request.nx_ip_driver_packet = request_ptr;
167 driver_request.nx_ip_driver_physical_address_msw = 0xFFFFUL;
168 driver_request.nx_ip_driver_physical_address_lsw = 0xFFFFFFFFUL;
169 driver_request.nx_ip_driver_interface = nx_interface;
170
171 /* If trace is enabled, insert this event into the trace buffer. */
172 NX_TRACE_IN_LINE_INSERT(NX_TRACE_INTERNAL_IO_DRIVER_ARP_SEND, ip_ptr, request_ptr, request_ptr -> nx_packet_length, 0, NX_TRACE_INTERNAL_EVENTS, 0, 0);
173
174 /* Add debug information. */
175 NX_PACKET_DEBUG(__FILE__, __LINE__, request_ptr);
176
177 /* Send the ARP request to the driver. */
178 /*lint -e{613} suppress possible use of null pointer, since nx_interface must not be NULL. */
179 (nx_interface -> nx_interface_link_driver_entry)(&driver_request);
180 }
181 #endif /* !NX_DISABLE_IPV4 */
182
183
