siphash24: let siphash24_finalize() and siphash24() return the result directly

Rather than passing a pointer to return the result, return it directly
from the function calls.

Also, return the result in native endianess, and let the callers care
about the conversion. For hash tables and bloom filters, we don't care,
but in order to keep MAC addresses and DHCP client IDs stable, we
explicitly convert to LE.

1 files changed, 5 insertions, 3 deletions

diff --git a/src/libsystemd-network/dhcp-identifier.c b/src/libsystemd-network/dhcp-identifier.c
index 368525c40a..d7ae865557 100644
--- a/src/libsystemd-network/dhcp-identifier.c
+++ b/src/libsystemd-network/dhcp-identifier.c
@@ -52,7 +52,7 @@ int dhcp_identifier_set_duid_en(struct duid *duid, size_t *len) {
 
         /* a bit of snake-oil perhaps, but no need to expose the machine-id
            directly; duid->en.id might not be aligned, so we need to copy */
-        siphash24(&hash, &machine_id, sizeof(machine_id), HASH_KEY.bytes);
+        hash = htole64(siphash24(&machine_id, sizeof(machine_id), HASH_KEY.bytes));
         memcpy(duid->en.id, &hash, sizeof(duid->en.id));
 
         return 0;
@@ -86,10 +86,12 @@ int dhcp_identifier_set_iaid(int ifindex, uint8_t *mac, size_t mac_len, void *_i
         }
 
         if (name)
-                siphash24(&id, name, strlen(name), HASH_KEY.bytes);
+                id = siphash24(name, strlen(name), HASH_KEY.bytes);
         else
                 /* fall back to MAC address if no predictable name available */
-                siphash24(&id, mac, mac_len, HASH_KEY.bytes);
+                id = siphash24(mac, mac_len, HASH_KEY.bytes);
+
+        id = htole64(id);
 
         /* fold into 32 bits */
         unaligned_write_be32(_id, (id & 0xffffffff) ^ (id >> 32));