meta-google: network-sh: Add ip_bytes_to_str
This makes it possible to get a human readable address back from a byte
array.
Change-Id: Ifcc98bcc95b8d75fe7d1aae1c264cbddf3fc5bd0
Signed-off-by: William A. Kennington III <wak@google.com>
diff --git a/meta-google/recipes-google/networking/network-sh/lib.sh b/meta-google/recipes-google/networking/network-sh/lib.sh
index 2dc5103..04e1480 100644
--- a/meta-google/recipes-google/networking/network-sh/lib.sh
+++ b/meta-google/recipes-google/networking/network-sh/lib.sh
@@ -153,6 +153,60 @@
bytes_out=("${bytes[@]}")
}
+ip_bytes_to_str() {
+ local -n bytes="$1"
+
+ if (( "${#bytes[@]}" == 4 )); then
+ printf '%d.%d.%d.%d\n' "${bytes[@]}"
+ elif (( "${#bytes[@]}" == 16 )); then
+ # Track the starting position of the longest run of 0 hextets (2 bytes)
+ local longest_i=0
+ # Track the size of the longest run of 0 hextets
+ local longest_s=0
+ # The index of the first 0 byte in the current run of zeros
+ local first_zero=0
+ local i
+ # Find the location of the longest run of zero hextets, preferring same
+ # size runs later in the address.
+ for (( i=0; i<=16; i+=2 )); do
+ # Terminate the run of zeros if we are at the end of the array or
+ # have a non-zero hextet
+ if (( i == 16 || bytes[$i] != 0 || bytes[$((i+1))] != 0 )); then
+ local s=$((i - first_zero))
+ if (( s >= longest_s )); then
+ longest_i=$first_zero
+ longest_s=$s
+ fi
+ first_zero=$((i+2))
+ fi
+ done
+ # Build the address string by each hextet
+ for (( i=0; i<16; i+=2 )); do
+ # If we encountered a run of zeros, add the necessary :: at the end
+ # of the string. If not at the end, a single : is added since : is
+ # printed to subsequent hextets already.
+ if (( i == longest_i )); then
+ (( i += longest_s-2 ))
+ printf ':'
+ # End of string needs to be ::
+ if (( i == 14 )); then
+ printf ':'
+ fi
+ else
+ # Prepend : to all hextets except the first for separation
+ if (( i != 0 )); then
+ printf ':'
+ fi
+ printf '%x' $(( (bytes[$i]<<8) | bytes[$(($i+1))]))
+ fi
+ done
+ printf '\n'
+ else
+ echo "Invalid IP Bytes: ${bytes[*]}" >&2
+ return 1
+ fi
+}
+
ipv6_pfx_concat() {
local pfx="$1"
local sfx="$2"
diff --git a/meta-google/recipes-google/networking/network-sh/test.sh b/meta-google/recipes-google/networking/network-sh/test.sh
index 2361cfe..33cab86 100755
--- a/meta-google/recipes-google/networking/network-sh/test.sh
+++ b/meta-google/recipes-google/networking/network-sh/test.sh
@@ -114,6 +114,36 @@
out=()
}
+test_ip4_bytes_str() {
+ in=(10 0 255 1)
+ str="$(ip_bytes_to_str in)" || fail
+ expect_streq "$str" '10.0.255.1'
+}
+
+test_ip6_bytes_str() {
+ in=(0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0)
+ str="$(ip_bytes_to_str in)" || fail
+ expect_streq "$str" '::'
+ in=(0xfd 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0)
+ str="$(ip_bytes_to_str in)" || fail
+ expect_streq "$str" 'fd00::'
+ in=(0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0xfd)
+ str="$(ip_bytes_to_str in)" || fail
+ expect_streq "$str" '::fd'
+ in=(0xfd 1 0 0 0 0 0 0 0 0 0 0 0 0 0 1)
+ str="$(ip_bytes_to_str in)" || fail
+ expect_streq "$str" 'fd01::1'
+ in=(0xfd 1 0 0 0 0 0 0 0 1 0 0 0 0 0 1)
+ str="$(ip_bytes_to_str in)" || fail
+ expect_streq "$str" 'fd01::1:0:0:1'
+ in=(0xfd 1 0 0 0 0 0 1 0 1 0 0 0 0 0 1)
+ str="$(ip_bytes_to_str in)" || fail
+ expect_streq "$str" 'fd01:0:0:1:1::1'
+ in=(0 1 0 1 0xdd 0xdd 0 1 0 1 0 1 0 1 0 1)
+ str="$(ip_bytes_to_str in)" || fail
+ expect_streq "$str" '1:1:dddd:1:1:1:1:1'
+}
+
test_ipv6_pfx_concat() {
# Invalid inputs
expect_err 1 ipv6_pfx_concat 'fd/64' '1234:5678:90af'