[systemd-devel] [PATCH 08/17] sd-dhcp-server: add support for setting the server address

[Zbigniew Jędrzejewski-Szmek]

On Mon, May 26, 2014 at 09:39:37PM +0200, Tom Gundersen wrote:
> ---
>  src/libsystemd-network/dhcp-server-internal.h |  1 +
>  src/libsystemd-network/sd-dhcp-server.c       | 13 +++++++++++++
>  src/libsystemd-network/test-dhcp-server.c     | 17 +++++++++++++++++
>  src/systemd/sd-dhcp-server.h                  |  1 +
>  4 files changed, 32 insertions(+)
> 
> diff --git a/src/libsystemd-network/dhcp-server-internal.h b/src/libsystemd-network/dhcp-server-internal.h
> index 6c2f2b4..58a9877 100644
> --- a/src/libsystemd-network/dhcp-server-internal.h
> +++ b/src/libsystemd-network/dhcp-server-internal.h
> @@ -39,6 +39,7 @@ struct sd_dhcp_server {
>          int fd_raw;
>  
>          int index;
> +        be32_t address;
>  };
>  
>  typedef struct DHCPClientId {
> diff --git a/src/libsystemd-network/sd-dhcp-server.c b/src/libsystemd-network/sd-dhcp-server.c
> index ecdc15d..7d6170c 100644
> --- a/src/libsystemd-network/sd-dhcp-server.c
> +++ b/src/libsystemd-network/sd-dhcp-server.c
> @@ -27,6 +27,17 @@
>  #include "dhcp-server-internal.h"
>  #include "dhcp-internal.h"
>  
> +int sd_dhcp_server_set_address(sd_dhcp_server *server, struct in_addr *address) {
> +        assert_return(server, -EINVAL);
> +        assert_return(address, -EINVAL);
> +        assert_return(address->s_addr, -EINVAL);
> +        assert_return(server->address == htobe32(INADDR_ANY), -EBUSY);
> +
> +        server->address = address->s_addr;
> +
> +        return 0;
> +}
> +
>  sd_dhcp_server *sd_dhcp_server_ref(sd_dhcp_server *server) {
>          if (server)
>                  assert_se(REFCNT_INC(server->n_ref) >= 2);
> @@ -60,6 +71,7 @@ int sd_dhcp_server_new(sd_dhcp_server **ret, int ifindex) {
>          server->n_ref = REFCNT_INIT;
>          server->fd_raw = -1;
>          server->fd = -1;
> +        server->address = htobe32(INADDR_ANY);
>          server->index = ifindex;
>  
>          *ret = server;
> @@ -281,6 +293,7 @@ int sd_dhcp_server_start(sd_dhcp_server *server) {
>          assert_return(!server->receive_message, -EBUSY);
>          assert_return(server->fd_raw == -1, -EBUSY);
>          assert_return(server->fd == -1, -EBUSY);
> +        assert_return(server->address != htobe32(INADDR_ANY), -EBUSY);

EBUSY seems rather confusing here, since actually the opposite is
true, for this newly added check as well for the preexisting ones:
the structure has not been initialized to be usable yet. Maybe a
different error code like EUNATCH or EBADRQC, ENODATA, EDESTADDRREQ or
EUCLEAN ?
  
>          r = socket(AF_PACKET, SOCK_DGRAM | SOCK_NONBLOCK, 0);
>          if (r < 0) {
> diff --git a/src/libsystemd-network/test-dhcp-server.c b/src/libsystemd-network/test-dhcp-server.c
> index dd0f29a..0cbb4df 100644
> --- a/src/libsystemd-network/test-dhcp-server.c
> +++ b/src/libsystemd-network/test-dhcp-server.c
> @@ -32,6 +32,12 @@
>  
>  static void test_basic(sd_event *event) {
>          _cleanup_dhcp_server_unref_ sd_dhcp_server *server = NULL;
> +        struct in_addr address_lo = {
> +                .s_addr = htonl(INADDR_LOOPBACK),
> +        };
> +        struct in_addr address_any = {
> +                .s_addr = htonl(INADDR_ANY),
> +        };
>  
>          /* attach to loopback interface */
>          assert_se(sd_dhcp_server_new(&server, 1) >= 0);
> @@ -48,6 +54,11 @@ static void test_basic(sd_event *event) {
>          assert_se(sd_dhcp_server_ref(server) == server);
>          assert_se(!sd_dhcp_server_unref(server));
>  
> +        assert_se(sd_dhcp_server_start(server) == -EBUSY);
> +        assert_se(sd_dhcp_server_set_address(server, &address_any) == -EINVAL);
> +        assert_se(sd_dhcp_server_set_address(server, &address_lo) >= 0);
> +        assert_se(sd_dhcp_server_set_address(server, &address_lo) == -EBUSY);
> +
>          assert_se(sd_dhcp_server_start(server) >= 0);
>          assert_se(sd_dhcp_server_start(server) == -EBUSY);
>          assert_se(sd_dhcp_server_stop(server) >= 0);
> @@ -74,8 +85,14 @@ static void test_message_handler(void) {
>                  .option_type.type = DHCP_DISCOVER,
>                  .end = DHCP_OPTION_END,
>          };
> +        struct in_addr address_lo = {
> +                .s_addr = htonl(INADDR_LOOPBACK),
> +        };
>  
>          assert_se(sd_dhcp_server_new(&server, 1) >= 0);
> +        assert_se(sd_dhcp_server_set_address(server, &address_lo) >= 0);
> +        assert_se(sd_dhcp_server_attach_event(server, NULL, 0) >= 0);
> +        assert_se(sd_dhcp_server_start(server) >= 0);
>  
>          assert_se(dhcp_server_handle_message(server, (DHCPMessage*)&test, sizeof(test)) == 1);
>  
> diff --git a/src/systemd/sd-dhcp-server.h b/src/systemd/sd-dhcp-server.h
> index ab63294..5edeffc 100644
> --- a/src/systemd/sd-dhcp-server.h
> +++ b/src/systemd/sd-dhcp-server.h
> @@ -41,4 +41,5 @@ sd_event *sd_dhcp_server_get_event(sd_dhcp_server *client);
>  int sd_dhcp_server_start(sd_dhcp_server *server);
>  int sd_dhcp_server_stop(sd_dhcp_server *server);
>  
> +int sd_dhcp_server_set_address(sd_dhcp_server *server, struct in_addr *address);
>  #endif

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