sd-dhcp6-client: Add basic DHCPv6 option handling

Add option appending and parsing. DHCPv6 options are not aligned, thus
the option handling code must be able to handle options starting at
any byte boundary.

Add a test case for the basic option handling.

1 files changed, 70 insertions, 0 deletions

diff --git a/src/libsystemd-network/test-dhcp6-client.c b/src/libsystemd-network/test-dhcp6-client.c
index b2dc8ba0c5..b52f40792b 100644
--- a/src/libsystemd-network/test-dhcp6-client.c
+++ b/src/libsystemd-network/test-dhcp6-client.c
@@ -28,6 +28,7 @@
 
 #include "sd-dhcp6-client.h"
 #include "dhcp6-protocol.h"
+#include "dhcp6-internal.h"
 
 static struct ether_addr mac_addr = {
         .ether_addr_octet = {'A', 'B', 'C', '1', '2', '3'}
@@ -61,6 +62,72 @@ static int test_client_basic(sd_event *e) {
         return 0;
 }
 
+static int test_option(sd_event *e) {
+        uint8_t packet[] = {
+                'F', 'O', 'O',
+                0x00, DHCP6_OPTION_ORO, 0x00, 0x07,
+                'A', 'B', 'C', 'D', 'E', 'F', 'G',
+                0x00, DHCP6_OPTION_VENDOR_CLASS, 0x00, 0x09,
+                '1', '2', '3', '4', '5', '6', '7', '8', '9',
+                'B', 'A', 'R',
+        };
+        uint8_t result[] = {
+                'F', 'O', 'O',
+                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+                'B', 'A', 'R',
+        };
+        uint16_t optcode;
+        size_t optlen;
+        uint8_t *optval, *buf, *out;
+        size_t zero = 0, pos = 3;
+        size_t buflen = sizeof(packet), outlen = sizeof(result);
+
+        if (verbose)
+                printf("* %s\n", __FUNCTION__);
+
+        assert_se(buflen == outlen);
+
+        assert_se(dhcp6_option_parse(&buf, &zero, &optcode, &optlen,
+                                     &optval) == -ENOMSG);
+
+        buflen -= 3;
+        buf = &packet[3];
+        outlen -= 3;
+        out = &result[3];
+
+        assert_se(dhcp6_option_parse(&buf, &buflen, &optcode, &optlen,
+                                     &optval) >= 0);
+        pos += 4 + optlen;
+        assert_se(buf == &packet[pos]);
+        assert_se(optcode == DHCP6_OPTION_ORO);
+        assert_se(optlen == 7);
+        assert_se(buflen + pos == sizeof(packet));
+
+        assert_se(dhcp6_option_append(&out, &outlen, optcode, optlen,
+                                      optval) >= 0);
+        assert_se(out == &result[pos]);
+        assert_se(*out == 0x00);
+
+        assert_se(dhcp6_option_parse(&buf, &buflen, &optcode, &optlen,
+                                     &optval) >= 0);
+        pos += 4 + optlen;
+        assert_se(buf == &packet[pos]);
+        assert_se(optcode == DHCP6_OPTION_VENDOR_CLASS);
+        assert_se(optlen == 9);
+        assert_se(buflen + pos == sizeof(packet));
+
+        assert_se(dhcp6_option_append(&out, &outlen, optcode, optlen,
+                                      optval) >= 0);
+        assert_se(out == &result[pos]);
+        assert_se(*out == 'B');
+
+        assert_se(memcmp(packet, result, sizeof(packet)) == 0);
+
+        return 0;
+}
+
 int main(int argc, char *argv[]) {
         _cleanup_event_unref_ sd_event *e;
 
@@ -71,6 +138,9 @@ int main(int argc, char *argv[]) {
         log_open();
 
         test_client_basic(e);
+        test_option(e);
+
+        assert_se(!sd_event_unref(e));
 
         return 0;
 }