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5
6
7#include "common.h"
8#include "d6_common.h"
9#include "dhcpc.h"
10#include "dhcpd.h"
11#include <netinet/in.h>
12#include <netinet/if_ether.h>
13#include <netpacket/packet.h>
14
15#if defined CONFIG_UDHCP_DEBUG && CONFIG_UDHCP_DEBUG >= 2
16void FAST_FUNC d6_dump_packet(struct d6_packet *packet)
17{
18 if (dhcp_verbose < 2)
19 return;
20
21 bb_info_msg(
22 " xid %x"
23 , packet->d6_xid32
24 );
25
26
27}
28#endif
29
30int FAST_FUNC d6_recv_kernel_packet(struct in6_addr *peer_ipv6
31 UNUSED_PARAM
32 , struct d6_packet *packet, int fd)
33{
34 int bytes;
35
36 memset(packet, 0, sizeof(*packet));
37 bytes = safe_read(fd, packet, sizeof(*packet));
38 if (bytes < 0) {
39 log1s("packet read error, ignoring");
40 return bytes;
41 }
42
43 if (bytes < offsetof(struct d6_packet, d6_options)) {
44 bb_simple_info_msg("packet with bad magic, ignoring");
45 return -2;
46 }
47 log2("received %s", "a packet");
48
49 d6_dump_packet(packet);
50
51 return bytes;
52}
53
54
55int FAST_FUNC d6_send_raw_packet_from_client_data_ifindex(
56 struct d6_packet *d6_pkt, unsigned d6_pkt_size,
57 struct in6_addr *src_ipv6, int source_port,
58 struct in6_addr *dst_ipv6, int dest_port, const uint8_t *dest_arp)
59{
60 struct sockaddr_ll dest_sll;
61 struct ip6_udp_d6_packet packet;
62 int fd;
63 int result = -1;
64 const char *msg;
65
66 fd = socket(PF_PACKET, SOCK_DGRAM, htons(ETH_P_IPV6));
67 if (fd < 0) {
68 msg = "socket(%s)";
69 goto ret_msg;
70 }
71
72 memset(&dest_sll, 0, sizeof(dest_sll));
73 memset(&packet, 0, offsetof(struct ip6_udp_d6_packet, data));
74 packet.data = *d6_pkt;
75
76 dest_sll.sll_family = AF_PACKET;
77 dest_sll.sll_protocol = htons(ETH_P_IPV6);
78 dest_sll.sll_ifindex = client_data.ifindex;
79
80
81 dest_sll.sll_halen = 6;
82 memcpy(dest_sll.sll_addr, dest_arp, 6);
83
84 if (bind(fd, (struct sockaddr *)&dest_sll, sizeof(dest_sll)) < 0) {
85 msg = "bind(%s)";
86 goto ret_close;
87 }
88
89 packet.ip6.ip6_vfc = (6 << 4);
90 if (src_ipv6)
91 packet.ip6.ip6_src = *src_ipv6;
92 packet.ip6.ip6_dst = *dst_ipv6;
93 packet.udp.source = htons(source_port);
94 packet.udp.dest = htons(dest_port);
95
96 packet.udp.len = htons(sizeof(struct udphdr) + d6_pkt_size);
97 packet.ip6.ip6_plen = packet.udp.len;
98
99
100
101
102
103
104
105 packet.ip6.ip6_hlim = IPPROTO_UDP;
106 packet.udp.check = inet_cksum(
107 (uint8_t *)&packet + 4,
108 offsetof(struct ip6_udp_d6_packet, data) - 4 + d6_pkt_size
109 );
110
111 packet.ip6.ip6_hlim = 1;
112 packet.ip6.ip6_nxt = IPPROTO_UDP;
113
114 d6_dump_packet(d6_pkt);
115 result = sendto(fd, &packet, offsetof(struct ip6_udp_d6_packet, data) + d6_pkt_size,
116 0,
117 (struct sockaddr *) &dest_sll, sizeof(dest_sll)
118 );
119 msg = "sendto";
120 ret_close:
121 close(fd);
122 if (result < 0) {
123 ret_msg:
124 bb_perror_msg(msg, "PACKET");
125 }
126 return result;
127}
128
129
130int FAST_FUNC d6_send_kernel_packet_from_client_data_ifindex(
131 struct d6_packet *d6_pkt, unsigned d6_pkt_size,
132 struct in6_addr *src_ipv6, int source_port,
133 struct in6_addr *dst_ipv6, int dest_port)
134{
135 struct sockaddr_in6 sa;
136 int fd;
137 int result = -1;
138 const char *msg;
139
140 fd = socket(PF_INET6, SOCK_DGRAM, IPPROTO_UDP);
141 if (fd < 0) {
142 msg = "socket(%s)";
143 goto ret_msg;
144 }
145 setsockopt_reuseaddr(fd);
146
147 memset(&sa, 0, sizeof(sa));
148 sa.sin6_family = AF_INET6;
149 sa.sin6_port = htons(source_port);
150 sa.sin6_addr = *src_ipv6;
151 if (bind(fd, (struct sockaddr *)&sa, sizeof(sa)) == -1) {
152 msg = "bind(%s)";
153 goto ret_close;
154 }
155
156 memset(&sa, 0, sizeof(sa));
157 sa.sin6_family = AF_INET6;
158 sa.sin6_port = htons(dest_port);
159 sa.sin6_addr = *dst_ipv6;
160 sa.sin6_scope_id = client_data.ifindex;
161 if (connect(fd, (struct sockaddr *)&sa, sizeof(sa)) == -1) {
162 msg = "connect";
163 goto ret_close;
164 }
165
166 d6_dump_packet(d6_pkt);
167 result = safe_write(fd, d6_pkt, d6_pkt_size);
168 msg = "write";
169 ret_close:
170 close(fd);
171 if (result < 0) {
172 ret_msg:
173 bb_perror_msg(msg, "UDP");
174 }
175 return result;
176}
177