diff options
Diffstat (limited to 'src/libsystemd-network/sd-dhcp-server.c')
| -rw-r--r-- | src/libsystemd-network/sd-dhcp-server.c | 16 |
1 files changed, 13 insertions, 3 deletions
diff --git a/src/libsystemd-network/sd-dhcp-server.c b/src/libsystemd-network/sd-dhcp-server.c index a46858258b..89b9a4c6be 100644 --- a/src/libsystemd-network/sd-dhcp-server.c +++ b/src/libsystemd-network/sd-dhcp-server.c @@ -669,6 +669,8 @@ static int get_pool_offset(sd_dhcp_server *server, be32_t requested_ip) { return be32toh(requested_ip) - be32toh(server->pool_start); } +#define HASH_KEY SD_ID128_MAKE(0d,1d,fe,bd,f1,24,bd,b3,47,f1,dd,6e,73,21,93,30) + int dhcp_server_handle_message(sd_dhcp_server *server, DHCPMessage *message, size_t length) { _cleanup_dhcp_request_free_ DHCPRequest *req = NULL; @@ -716,12 +718,20 @@ int dhcp_server_handle_message(sd_dhcp_server *server, DHCPMessage *message, if (existing_lease) address = existing_lease->address; else { + size_t next_offer; + + /* even with no persistence of leases, we try to offer the same client + the same IP address. we do this by using the hash of the client id + as the offset into the pool of leases when finding the next free one */ + + next_offer = client_id_hash_func(&req->client_id, HASH_KEY.bytes) % server->pool_size; + for (i = 0; i < server->pool_size; i++) { - if (!server->bound_leases[server->next_offer]) { - address = htobe32(be32toh(server->pool_start) + server->next_offer); + if (!server->bound_leases[next_offer]) { + address = htobe32(be32toh(server->pool_start) + next_offer); break; } else - server->next_offer = (server->next_offer + 1) % server->pool_size; + next_offer = (next_offer + 1) % server->pool_size; } } |