@@ -1730,6 +1730,62 @@ ipv6_to_bytes()
expand_ipv6 "$IP" :
}
+u16_to_bytes()
+{
+ local u16=$1; shift
+
+ printf "%04x" $u16 | sed 's/^/000/;s/^.*\(..\)\(..\)$/\1:\2/'
+}
+
+# Given a mausezahn-formatted payload (colon-separated bytes given as %02x),
+# possibly with a keyword CHECKSUM stashed where a 16-bit checksum should be,
+# calculate checksum as per RFC 1071, assuming the CHECKSUM field (if any)
+# stands for 00:00.
+payload_template_calc_checksum()
+{
+ local payload=$1; shift
+
+ (
+ # Set input radix.
+ echo "16i"
+ # Push zero for the initial checksum.
+ echo 0
+
+ # Pad the payload with a terminating 00: in case we get an odd
+ # number of bytes.
+ echo "${payload%:}:00:" |
+ sed 's/CHECKSUM/00:00/g' |
+ tr '[:lower:]' '[:upper:]' |
+ # Add the word to the checksum.
+ sed 's/\(..\):\(..\):/\1\2+\n/g' |
+ # Strip the extra odd byte we pushed if left unconverted.
+ sed 's/\(..\):$//'
+
+ echo "10000 ~ +" # Calculate and add carry.
+ echo "FFFF r - p" # Bit-flip and print.
+ ) |
+ dc |
+ tr '[:upper:]' '[:lower:]'
+}
+
+payload_template_expand_checksum()
+{
+ local payload=$1; shift
+ local checksum=$1; shift
+
+ local ckbytes=$(u16_to_bytes $checksum)
+
+ echo "$payload" | sed "s/CHECKSUM/$ckbytes/g"
+}
+
+payload_template_nbytes()
+{
+ local payload=$1; shift
+
+ payload_template_expand_checksum "${payload%:}" 0 |
+ sed 's/:/\n/g' | wc -l
+}
+
igmpv3_is_in_get()
{
local igmpv3