DHCP DUID and IAID configurability

7 files changed, 138 insertions, 41 deletions

diff --git a/src/libsystemd-network/dhcp-identifier.c b/src/libsystemd-network/dhcp-identifier.c
index 1d9ec7be82..1bef368852 100644
--- a/src/libsystemd-network/dhcp-identifier.c
+++ b/src/libsystemd-network/dhcp-identifier.c
@@ -43,7 +43,7 @@ int dhcp_identifier_set_duid_en(struct duid *duid, size_t *len) {
         if (r < 0)
                 return r;
 
-        unaligned_write_be16(&duid->type, DHCP6_DUID_EN);
+        unaligned_write_be16(&duid->type, DHCP_DUID_TYPE_EN);
         unaligned_write_be32(&duid->en.pen, SYSTEMD_PEN);
 
         *len = sizeof(duid->type) + sizeof(duid->en);
diff --git a/src/libsystemd-network/dhcp-identifier.h b/src/libsystemd-network/dhcp-identifier.h
index 93f06f5938..cb953cb416 100644
--- a/src/libsystemd-network/dhcp-identifier.h
+++ b/src/libsystemd-network/dhcp-identifier.h
@@ -25,13 +25,23 @@
 #include "sparse-endian.h"
 #include "unaligned.h"
 
+typedef enum DHCPDUIDType {
+        DHCP_DUID_TYPE_RAW       = 0,
+        DHCP_DUID_TYPE_LLT       = 1,
+        DHCP_DUID_TYPE_EN        = 2,
+        DHCP_DUID_TYPE_LL        = 3,
+        DHCP_DUID_TYPE_UUID      = 4,
+        _DHCP_DUID_TYPE_MAX,
+        _DHCP_DUID_TYPE_INVALID  = -1,
+} DHCPDUIDType;
+
 /* RFC 3315 section 9.1:
  *      A DUID can be no more than 128 octets long (not including the type code).
  */
 #define MAX_DUID_LEN 128
 
 struct duid {
-        uint16_t type;
+        be16_t type;
         union {
                 struct {
                         /* DHCP6_DUID_LLT */
@@ -61,3 +71,32 @@ struct duid {
 
 int dhcp_identifier_set_duid_en(struct duid *duid, size_t *len);
 int dhcp_identifier_set_iaid(int ifindex, uint8_t *mac, size_t mac_len, void *_id);
+
+static inline int dhcp_validate_duid_len(be16_t duid_type, size_t duid_len) {
+        struct duid d;
+
+        assert_return(duid_len > 0 && duid_len <= MAX_DUID_LEN, -EINVAL);
+
+        switch (be16toh(duid_type)) {
+        case DHCP_DUID_TYPE_LLT:
+                if (duid_len <= sizeof(d.llt))
+                        return -EINVAL;
+                break;
+        case DHCP_DUID_TYPE_EN:
+                if (duid_len != sizeof(d.en))
+                        return -EINVAL;
+                break;
+        case DHCP_DUID_TYPE_LL:
+                if (duid_len <= sizeof(d.ll))
+                        return -EINVAL;
+                break;
+        case DHCP_DUID_TYPE_UUID:
+                if (duid_len != sizeof(d.uuid))
+                        return -EINVAL;
+                break;
+        default:
+                /* accept unknown type in order to be forward compatible */
+                break;
+        }
+        return 0;
+}
diff --git a/src/libsystemd-network/dhcp6-protocol.h b/src/libsystemd-network/dhcp6-protocol.h
index ee4bdfb07f..2487c470ab 100644
--- a/src/libsystemd-network/dhcp6-protocol.h
+++ b/src/libsystemd-network/dhcp6-protocol.h
@@ -62,13 +62,6 @@ enum {
 #define DHCP6_REB_TIMEOUT                       10 * USEC_PER_SEC
 #define DHCP6_REB_MAX_RT                        600 * USEC_PER_SEC
 
-enum {
-        DHCP6_DUID_LLT                          = 1,
-        DHCP6_DUID_EN                           = 2,
-        DHCP6_DUID_LL                           = 3,
-        DHCP6_DUID_UUID                         = 4,
-};
-
 enum DHCP6State {
         DHCP6_STATE_STOPPED                     = 0,
         DHCP6_STATE_INFORMATION_REQUEST         = 1,
diff --git a/src/libsystemd-network/network-internal.c b/src/libsystemd-network/network-internal.c
index cb7252bbeb..7c21f42591 100644
--- a/src/libsystemd-network/network-internal.c
+++ b/src/libsystemd-network/network-internal.c
@@ -335,6 +335,34 @@ int config_parse_hwaddr(const char *unit,
         return 0;
 }
 
+int config_parse_iaid_value(const char *unit,
+                            const char *filename,
+                            unsigned line,
+                            const char *section,
+                            unsigned section_line,
+                            const char *lvalue,
+                            int ltype,
+                            const char *rvalue,
+                            void *data,
+                            void *userdata) {
+        uint32_t iaid_value;
+        int r;
+
+        assert(filename);
+        assert(lvalue);
+        assert(rvalue);
+        assert(data);
+
+        if ((r = safe_atou32(rvalue, &iaid_value)) < 0) {
+                log_syntax(unit, LOG_ERR, filename, line, 0, "Unable to read IAID: %s", rvalue);
+                return r;
+        }
+
+        *((be32_t *)data) = htobe32(iaid_value);
+
+        return 0;
+}
+
 void serialize_in_addrs(FILE *f, const struct in_addr *addresses, size_t size) {
         unsigned i;
 
diff --git a/src/libsystemd-network/network-internal.h b/src/libsystemd-network/network-internal.h
index c8a531ab0f..d8b551e8ce 100644
--- a/src/libsystemd-network/network-internal.h
+++ b/src/libsystemd-network/network-internal.h
@@ -62,6 +62,10 @@ int config_parse_ifalias(const char *unit, const char *filename, unsigned line,
                          const char *section, unsigned section_line, const char *lvalue,
                          int ltype, const char *rvalue, void *data, void *userdata);
 
+int config_parse_iaid_value(const char *unit, const char *filename, unsigned line,
+                            const char *section, unsigned section_line, const char *lvalue,
+                            int ltype, const char *rvalue, void *data, void *userdata);
+
 int net_get_unique_predictable_data(struct udev_device *device, uint64_t *result);
 const char *net_get_name(struct udev_device *device);
 
diff --git a/src/libsystemd-network/sd-dhcp-client.c b/src/libsystemd-network/sd-dhcp-client.c
index 1188b31500..b108e35386 100644
--- a/src/libsystemd-network/sd-dhcp-client.c
+++ b/src/libsystemd-network/sd-dhcp-client.c
@@ -82,7 +82,7 @@ struct sd_dhcp_client {
                         } _packed_ ll;
                         struct {
                                 /* 255: Node-specific (RFC 4361) */
-                                uint32_t iaid;
+                                be32_t iaid;
                                 struct duid duid;
                         } _packed_ ns;
                         struct {
@@ -298,6 +298,51 @@ int sd_dhcp_client_set_client_id(sd_dhcp_client *client, uint8_t type,
         return 0;
 }
 
+int sd_dhcp_client_set_iaid_duid(sd_dhcp_client *client, be32_t iaid,
+                                 size_t duid_len, struct duid *duid) {
+        DHCP_CLIENT_DONT_DESTROY(client);
+        int r;
+        assert_return(client, -EINVAL);
+        zero(client->client_id);
+
+        client->client_id.type = 255;
+
+        /* If IAID is not configured, generate it. */
+        if (iaid == 0) {
+                r = dhcp_identifier_set_iaid(client->index, client->mac_addr,
+                                             client->mac_addr_len,
+                                             &client->client_id.ns.iaid);
+                if (r < 0)
+                        return r;
+        } else
+                client->client_id.ns.iaid = iaid;
+
+        /* If DUID is not configured, generate DUID-EN. */
+        if (duid_len == 0) {
+                r = dhcp_identifier_set_duid_en(&client->client_id.ns.duid,
+                                                &duid_len);
+                if (r < 0)
+                        return r;
+        } else {
+                r = dhcp_validate_duid_len(client->client_id.type,
+                                           duid_len - sizeof(client->client_id.type));
+                if (r < 0)
+                        return r;
+                memcpy(&client->client_id.ns.duid, duid, duid_len);
+        }
+
+        client->client_id_len = sizeof(client->client_id.type) + duid_len +
+                                sizeof(client->client_id.ns.iaid);
+
+        if (!IN_SET(client->state, DHCP_STATE_INIT, DHCP_STATE_STOPPED)) {
+                log_dhcp_client(client, "Configured IAID+DUID, restarting.");
+                client_stop(client, SD_DHCP_CLIENT_EVENT_STOP);
+                sd_dhcp_client_start(client);
+        }
+
+        return 0;
+}
+
 int sd_dhcp_client_set_hostname(sd_dhcp_client *client,
                                 const char *hostname) {
         char *new_hostname = NULL;
@@ -469,7 +514,6 @@ static int client_message_init(sd_dhcp_client *client, DHCPPacket **ret,
         if (client->arp_type == ARPHRD_ETHER)
                 memcpy(&packet->dhcp.chaddr, &client->mac_addr, ETH_ALEN);
 
-        /* If no client identifier exists, construct an RFC 4361-compliant one */
         if (client->client_id_len == 0) {
                 size_t duid_len;
 
diff --git a/src/libsystemd-network/sd-dhcp6-client.c b/src/libsystemd-network/sd-dhcp6-client.c
index af4709d788..7cecba120c 100644
--- a/src/libsystemd-network/sd-dhcp6-client.c
+++ b/src/libsystemd-network/sd-dhcp6-client.c
@@ -180,41 +180,30 @@ static int client_ensure_duid(sd_dhcp6_client *client) {
         return dhcp_identifier_set_duid_en(&client->duid, &client->duid_len);
 }
 
-int sd_dhcp6_client_set_duid(
-                sd_dhcp6_client *client,
-                uint16_t type,
-                uint8_t *duid, size_t duid_len) {
+int sd_dhcp6_client_set_duid(sd_dhcp6_client *client, size_t duid_len,
+                             struct duid *duid) {
+        int r;
         assert_return(client, -EINVAL);
-        assert_return(duid, -EINVAL);
-        assert_return(duid_len > 0 && duid_len <= MAX_DUID_LEN, -EINVAL);
-
         assert_return(IN_SET(client->state, DHCP6_STATE_STOPPED), -EBUSY);
 
-        switch (type) {
-        case DHCP6_DUID_LLT:
-                if (duid_len <= sizeof(client->duid.llt))
-                        return -EINVAL;
-                break;
-        case DHCP6_DUID_EN:
-                if (duid_len != sizeof(client->duid.en))
-                        return -EINVAL;
-                break;
-        case DHCP6_DUID_LL:
-                if (duid_len <= sizeof(client->duid.ll))
-                        return -EINVAL;
-                break;
-        case DHCP6_DUID_UUID:
-                if (duid_len != sizeof(client->duid.uuid))
-                        return -EINVAL;
-                break;
-        default:
-                /* accept unknown type in order to be forward compatible */
-                break;
+        if (duid_len > 0) {
+                r = dhcp_validate_duid_len(duid->type,
+                                           duid_len - sizeof(duid->type));
+                if (r < 0)
+                        return r;
+
+                memcpy(&client->duid, duid, duid_len);
+                client->duid_len = duid_len;
         }
 
-        client->duid.type = htobe16(type);
-        memcpy(&client->duid.raw.data, duid, duid_len);
-        client->duid_len = duid_len + sizeof(client->duid.type);
+        return 0;
+}
+
+int sd_dhcp6_client_set_iaid(sd_dhcp6_client *client, be32_t iaid) {
+        assert_return(client, -EINVAL);
+        assert_return(IN_SET(client->state, DHCP6_STATE_STOPPED), -EBUSY);
+
+        client->ia_na.id = iaid;
 
         return 0;
 }