1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
|
#include <doctest/doctest.h>
#include <vector>
#include "wireframe/net/ipv4.hpp" // for kProtoTcp
#include "wireframe/net/ipv6.hpp"
using namespace wireframe::net;
namespace {
Ipv6Address addr_from_groups(std::array<std::uint16_t, 8> groups) {
Ipv6Address addr{};
for (std::size_t i = 0; i < 8; ++i) {
addr.bytes[i * 2] = static_cast<unsigned char>(groups[i] >> 8);
addr.bytes[i * 2 + 1] = static_cast<unsigned char>(groups[i] & 0xFF);
}
return addr;
}
} // namespace
TEST_CASE("parse_ipv6 decodes header fields and leaves the right payload") {
std::vector<unsigned char> bytes(40, 0);
bytes[0] = 0x60; // version 6, traffic class high nibble 0
bytes[1] = 0x00; // traffic class low nibble 0, flow label starts 0
bytes[4] = 0x00;
bytes[5] = 0x04; // payload_length = 4
bytes[6] = kProtoTcp;
bytes[7] = 64; // hop_limit
// src = 2001:0db8::1
bytes[8] = 0x20; bytes[9] = 0x01; bytes[10] = 0x0d; bytes[11] = 0xb8;
bytes[23] = 0x01;
// dst = ::1
bytes[39] = 0x01;
bytes.insert(bytes.end(), {0xAA, 0xBB, 0xCC, 0xDD});
auto ip6 = parse_ipv6(bytes);
REQUIRE(ip6.has_value());
CHECK(ip6->header.version == 6);
CHECK(ip6->header.payload_length == 4);
CHECK(ip6->header.next_header == kProtoTcp);
CHECK(ip6->header.hop_limit == 64);
REQUIRE(ip6->payload.size() == 4);
CHECK(ip6->payload[0] == 0xAA);
}
TEST_CASE("parse_ipv6 rejects a non-IPv6 version") {
std::vector<unsigned char> bytes(40, 0);
bytes[0] = 0x45; // version 4
CHECK_FALSE(parse_ipv6(bytes).has_value());
}
TEST_CASE("parse_ipv6 rejects a buffer shorter than the 40-byte header") {
std::vector<unsigned char> bytes(39, 0);
bytes[0] = 0x60;
CHECK_FALSE(parse_ipv6(bytes).has_value());
}
TEST_CASE("ipv6_to_string compresses the loopback address") {
CHECK(ipv6_to_string(addr_from_groups({0, 0, 0, 0, 0, 0, 0, 1})) == "::1");
}
TEST_CASE("ipv6_to_string compresses the unspecified address") {
CHECK(ipv6_to_string(addr_from_groups({0, 0, 0, 0, 0, 0, 0, 0})) == "::");
}
TEST_CASE("ipv6_to_string compresses a zero run in the middle") {
CHECK(ipv6_to_string(addr_from_groups({0x2001, 0x0db8, 0, 0, 0, 0, 0, 1})) == "2001:db8::1");
}
TEST_CASE("ipv6_to_string does not compress a lone zero group") {
CHECK(ipv6_to_string(addr_from_groups({0x2001, 0, 0x0db8, 1, 1, 1, 1, 1})) ==
"2001:0:db8:1:1:1:1:1");
}
TEST_CASE("ipv6_to_string picks the leftmost run when two runs tie in length") {
// Two runs of length 2: groups[1..2] and groups[5..6]. Leftmost wins.
CHECK(ipv6_to_string(addr_from_groups({1, 0, 0, 2, 3, 0, 0, 4})) == "1::2:3:0:0:4");
}
TEST_CASE("ipv6_to_string leaves an address with no zero run untouched") {
CHECK(ipv6_to_string(addr_from_groups({1, 2, 3, 4, 5, 6, 7, 8})) == "1:2:3:4:5:6:7:8");
}
TEST_CASE("walk_ipv6_extension_headers passes a direct transport protocol through unchanged") {
std::vector<unsigned char> payload = {0xAA, 0xBB, 0xCC};
auto result = walk_ipv6_extension_headers(kProtoTcp, payload);
CHECK(result.final_next_header == kProtoTcp);
CHECK_FALSE(result.stopped_at_esp);
REQUIRE(result.payload.size() == 3);
CHECK(result.payload[0] == 0xAA);
}
TEST_CASE("walk_ipv6_extension_headers walks a single Hop-by-Hop header to reach TCP") {
// Hop-by-Hop: next_header(1)=TCP, hdr_ext_len(1)=0 -> total len (0+1)*8=8 bytes.
std::vector<unsigned char> payload = {static_cast<unsigned char>(kProtoTcp), 0x00,
0, 0, 0, 0, 0, 0}; // 6 bytes of option padding
std::vector<unsigned char> tcp_marker = {0xDE, 0xAD};
payload.insert(payload.end(), tcp_marker.begin(), tcp_marker.end());
auto result = walk_ipv6_extension_headers(kNextHeaderHopByHop, payload);
CHECK(result.final_next_header == kProtoTcp);
CHECK_FALSE(result.stopped_at_esp);
REQUIRE(result.payload.size() == 2);
CHECK(result.payload[0] == 0xDE);
}
TEST_CASE("walk_ipv6_extension_headers walks a chain of two extension headers") {
// Hop-by-Hop (8 bytes) -> Destination Options (8 bytes) -> UDP.
std::vector<unsigned char> payload = {
kNextHeaderDestOptions, 0x00, 0, 0, 0, 0, 0, 0, // Hop-by-Hop, len 8
static_cast<unsigned char>(kProtoUdp), 0x00, 0, 0, 0, 0, 0, 0, // Dest Options, len 8
0xFE, 0xED, // "UDP header" marker
};
auto result = walk_ipv6_extension_headers(kNextHeaderHopByHop, payload);
CHECK(result.final_next_header == kProtoUdp);
REQUIRE(result.payload.size() == 2);
CHECK(result.payload[0] == 0xFE);
}
TEST_CASE("walk_ipv6_extension_headers walks the fixed-size Fragment header") {
std::vector<unsigned char> payload = {static_cast<unsigned char>(kProtoTcp), 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x01, // 8-byte fragment header
0xCA, 0xFE};
auto result = walk_ipv6_extension_headers(kNextHeaderFragment, payload);
CHECK(result.final_next_header == kProtoTcp);
REQUIRE(result.payload.size() == 2);
CHECK(result.payload[0] == 0xCA);
}
TEST_CASE("walk_ipv6_extension_headers applies AH's 4-byte-unit length formula") {
// AH: next_header(1)=TCP, payload_len(1)=1 -> total len (1+2)*4=12 bytes.
std::vector<unsigned char> payload(12, 0);
payload[0] = static_cast<unsigned char>(kProtoTcp);
payload[1] = 0x01;
payload.push_back(0x11);
payload.push_back(0x22);
auto result = walk_ipv6_extension_headers(kNextHeaderAh, payload);
CHECK(result.final_next_header == kProtoTcp);
REQUIRE(result.payload.size() == 2);
CHECK(result.payload[0] == 0x11);
}
TEST_CASE("walk_ipv6_extension_headers stops at ESP without guessing past it") {
std::vector<unsigned char> payload = {0x01, 0x02, 0x03, 0x04};
auto result = walk_ipv6_extension_headers(kNextHeaderEsp, payload);
CHECK(result.stopped_at_esp);
CHECK(result.final_next_header == kNextHeaderEsp);
REQUIRE(result.payload.size() == 4);
CHECK(result.payload[0] == 0x01); // untouched: ESP payload starts right here
}
TEST_CASE("walk_ipv6_extension_headers stops gracefully on a truncated extension header") {
std::vector<unsigned char> payload = {static_cast<unsigned char>(kProtoTcp),
0xFF}; // claims (255+1)*8 bytes; nowhere near present
auto result = walk_ipv6_extension_headers(kNextHeaderHopByHop, payload);
CHECK(result.final_next_header == kNextHeaderHopByHop); // never resolved past it
CHECK_FALSE(result.stopped_at_esp);
}
TEST_CASE("walk_ipv6_extension_headers passes an unknown next_header through untouched") {
std::vector<unsigned char> payload = {0x01, 0x02};
auto result = walk_ipv6_extension_headers(200, payload); // not a known extension type
CHECK(result.final_next_header == 200);
REQUIRE(result.payload.size() == 2);
CHECK(result.payload[0] == 0x01);
}
|