dhcpv4: use iovec for forcerenew opts

That's the last bunch of options :)

Signed-off-by: David Härdeman <[email protected]>
Link: https://github.com/openwrt/odhcpd/pull/278
Signed-off-by: Álvaro Fernández Rojas <[email protected]>

diff --git a/src/dhcpv4.c b/src/dhcpv4.c
index df019a9ad8c5b3f6f445b37c292bff6a0f98e338..70b36be8c061f6a770f674aa35fe7dafec5fdae5 100644 (file)
--- a/src/dhcpv4.c
+++ b/src/dhcpv4.c
@@ -635,8 +635,11 @@ enum {
        IOV_LEASETIME,
        IOV_RENEW,
        IOV_REBIND,
+       IOV_AUTH,
+       IOV_AUTH_BODY,
        IOV_SRCH_DOMAIN,
        IOV_SRCH_DOMAIN_NAME,
+       IOV_FR_NONCE_CAP,
        IOV_DNR,
        IOV_DNR_BODY,
        IOV_END,
@@ -719,9 +722,25 @@ void dhcpv4_handle_msg(void *src_addr, void *data, size_t len,
                .code = DHCPV4_OPT_REBIND,
                .len = sizeof(uint32_t),
        };
+       struct dhcpv4_auth_forcerenew reply_auth_body = {
+               .protocol = DHCPV4_AUTH_PROTO_RKAP,
+               .algorithm = DHCPV4_AUTH_ALG_HMAC_MD5,
+               .rdm = DHCPV4_AUTH_RDM_MONOTONIC,
+               .type = DHCPV4_AUTH_RKAP_AI_TYPE_KEY,
+               .key = { 0 },
+       };
+       struct dhcpv4_option reply_auth = {
+               .code = DHCPV4_OPT_AUTHENTICATION,
+               .len = sizeof(reply_auth_body),
+       };
        struct dhcpv4_option reply_srch_domain = {
                .code = DHCPV4_OPT_SEARCH_DOMAIN,
        };
+       struct dhcpv4_option_u8 reply_fr_nonce_cap = {
+               .code = DHCPV4_OPT_FORCERENEW_NONCE_CAPABLE,
+               .len = sizeof(uint8_t),
+               .data = 1,
+       };
        struct dhcpv4_option reply_dnr = {
                .code = DHCPV4_OPT_DNR,
        };
@@ -730,7 +749,7 @@ void dhcpv4_handle_msg(void *src_addr, void *data, size_t len,
        size_t reply_opts_len = 0;
 
        struct iovec iov[IOV_TOTAL] = {
-               [IOV_HEADER]            = { &reply, 0 },
+               [IOV_HEADER]            = { &reply, offsetof(typeof(reply), options) },
                [IOV_MESSAGE]           = { &reply_msg, sizeof(reply_msg) },
                [IOV_SERVERID]          = { &reply_serverid, sizeof(reply_serverid) },
                [IOV_NETMASK]           = { &reply_netmask, 0 },
@@ -747,8 +766,11 @@ void dhcpv4_handle_msg(void *src_addr, void *data, size_t len,
                [IOV_LEASETIME]         = { &reply_leasetime, 0 },
                [IOV_RENEW]             = { &reply_renew, 0 },
                [IOV_REBIND]            = { &reply_rebind, 0 },
+               [IOV_AUTH]              = { &reply_auth, 0 },
+               [IOV_AUTH_BODY]         = { &reply_auth_body, 0 },
                [IOV_SRCH_DOMAIN]       = { &reply_srch_domain, 0 },
                [IOV_SRCH_DOMAIN_NAME]  = { NULL, 0 },
+               [IOV_FR_NONCE_CAP]      = { &reply_fr_nonce_cap, 0 },
                [IOV_DNR]               = { &reply_dnr, 0 },
                [IOV_DNR_BODY]          = { NULL, 0 },
                [IOV_END]               = { &reply_end, sizeof(reply_end) },
@@ -756,7 +778,6 @@ void dhcpv4_handle_msg(void *src_addr, void *data, size_t len,
 
        /* Misc */
        struct sockaddr_in dest_addr;
-       uint8_t *cursor = reply.options;
        bool incl_fr_opt = false;
        struct dhcp_assignment *a = NULL;
        uint32_t fr_serverid = INADDR_ANY;
@@ -901,7 +922,6 @@ void dhcpv4_handle_msg(void *src_addr, void *data, size_t len,
        }
 
        reply_opts = alloca(req_opts_len + 32);
-
        reply_opts[reply_opts_len++] = DHCPV4_OPT_NETMASK;
        reply_opts[reply_opts_len++] = DHCPV4_OPT_ROUTER;
        reply_opts[reply_opts_len++] = DHCPV4_OPT_DNSSERVER;
@@ -911,34 +931,13 @@ void dhcpv4_handle_msg(void *src_addr, void *data, size_t len,
        reply_opts[reply_opts_len++] = DHCPV4_OPT_LEASETIME;
        reply_opts[reply_opts_len++] = DHCPV4_OPT_RENEW;
        reply_opts[reply_opts_len++] = DHCPV4_OPT_REBIND;
+       reply_opts[reply_opts_len++] = DHCPV4_OPT_AUTHENTICATION;
        reply_opts[reply_opts_len++] = DHCPV4_OPT_SEARCH_DOMAIN;
+       reply_opts[reply_opts_len++] = DHCPV4_OPT_FORCERENEW_NONCE_CAPABLE;
 
-       if (a) {
+       if (a)
                reply.yiaddr.s_addr = a->addr;
 
-               if (incl_fr_opt) {
-                       if (req_msg == DHCPV4_MSG_REQUEST) {
-                               struct dhcpv4_auth_forcerenew auth = {
-                                       .protocol = DHCPV4_AUTH_PROTO_RKAP,
-                                       .algorithm = DHCPV4_AUTH_ALG_HMAC_MD5,
-                                       .rdm = DHCPV4_AUTH_RDM_MONOTONIC,
-                                       .replay = { htonl(time(NULL)), htonl(++serial) },
-                                       .type = DHCPV4_AUTH_RKAP_AI_TYPE_KEY,
-                                       .key = { 0 },
-                               };
-
-                               memcpy(auth.key, a->key, sizeof(auth.key));
-                               dhcpv4_put(&reply, &cursor, DHCPV4_OPT_AUTHENTICATION, sizeof(auth), &auth);
-                               reply_opts[reply_opts_len++] = DHCPV4_OPT_AUTHENTICATION;
-                       } else {
-                               uint8_t one = 1;
-                               dhcpv4_put(&reply, &cursor, DHCPV4_OPT_FORCERENEW_NONCE_CAPABLE,
-                                       sizeof(one), &one);
-                               reply_opts[reply_opts_len++] = DHCPV4_OPT_FORCERENEW_NONCE_CAPABLE;
-                       }
-               }
-       }
-
        memcpy(&reply_opts[reply_opts_len], req_opts, req_opts_len);
        reply_opts_len += req_opts_len;
 
@@ -1033,6 +1032,17 @@ void dhcpv4_handle_msg(void *src_addr, void *data, size_t len,
                        iov[IOV_REBIND].iov_len = sizeof(reply_rebind);
                        break;
 
+               case DHCPV4_OPT_AUTHENTICATION:
+                       if (!a || !incl_fr_opt || req_msg != DHCPV4_MSG_REQUEST)
+                               break;
+
+                       memcpy(reply_auth_body.key, a->key, sizeof(reply_auth_body.key));
+                       reply_auth_body.replay[0] = htonl(time(NULL));
+                       reply_auth_body.replay[1] = htonl(++serial);
+                       iov[IOV_AUTH].iov_len = sizeof(reply_auth);
+                       iov[IOV_AUTH_BODY].iov_len = sizeof(reply_auth_body);
+                       break;
+
                case DHCPV4_OPT_SEARCH_DOMAIN:
                        if (iov[IOV_SRCH_DOMAIN].iov_len || iface->search_len > UINT8_MAX)
                                break;
@@ -1060,6 +1070,13 @@ void dhcpv4_handle_msg(void *src_addr, void *data, size_t len,
                        }
                        break;
 
+               case DHCPV4_OPT_FORCERENEW_NONCE_CAPABLE:
+                       if (!a || !incl_fr_opt || req_msg == DHCPV4_MSG_REQUEST)
+                               break;
+
+                       iov[IOV_FR_NONCE_CAP].iov_len = sizeof(reply_fr_nonce_cap);
+                       break;
+
                case DHCPV4_OPT_DNR:
                        struct dhcpv4_dnr *dnrs;
                        size_t dnrs_len = 0;
@@ -1134,7 +1151,6 @@ void dhcpv4_handle_msg(void *src_addr, void *data, size_t len,
        dhcpv4_set_dest_addr(iface, reply_msg.data, req, &reply, src_addr, &dest_addr);
 
        /* FIXME: check for DHCPV4_MIN_PACKET_SIZE */
-       iov[IOV_HEADER].iov_len = (size_t)(cursor - (uint8_t *)&reply);
 
        if (send_reply(iov, ARRAY_SIZE(iov), (struct sockaddr *)&dest_addr, sizeof(dest_addr), opaque) < 0)
                error("Failed to send %s to %s - %s: %m",