slirp: Add domainname option to slirp's DHCP server

This patch will allow the user to include the domainname option in
replies from the built-in DHCP server.

Signed-off-by: Benjamin Drung <benjamin.drung@profitbricks.com>
Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>

4 files changed, 15 insertions, 2 deletions

diff --git a/bootp.c b/bootp.c
index 810da0c..4abd455 100644
--- a/bootp.c
+++ b/bootp.c
@@ -303,6 +303,14 @@ static void bootp_reply(Slirp *slirp, const struct bootp_t *bp)
             q += val;
         }
 
+        if (slirp->vdomainname) {
+            val = strlen(slirp->vdomainname);
+            *q++ = RFC1533_DOMAINNAME;
+            *q++ = val;
+            memcpy(q, slirp->vdomainname, val);
+            q += val;
+        }
+
         if (slirp->vdnssearch) {
             size_t spaceleft = sizeof(rbp->bp_vend) - (q - rbp->bp_vend);
             val = slirp->vdnssearch_len;
diff --git a/libslirp.h b/libslirp.h
index da7d777..eddac37 100644
--- a/libslirp.h
+++ b/libslirp.h
@@ -15,7 +15,8 @@ Slirp *slirp_init(int restricted, bool in_enabled, struct in_addr vnetwork,
                   const char *vhostname, const char *tftp_path,
                   const char *bootfile, struct in_addr vdhcp_start,
                   struct in_addr vnameserver, struct in6_addr vnameserver6,
-                  const char **vdnssearch, void *opaque);
+                  const char **vdnssearch, const char *vdomainname,
+                  void *opaque);
 void slirp_cleanup(Slirp *slirp);
 
 void slirp_pollfds_fill(GArray *pollfds, uint32_t *timeout);
diff --git a/slirp.c b/slirp.c
index c408f9c..0e8fa8c 100644
--- a/slirp.c
+++ b/slirp.c
@@ -284,7 +284,8 @@ Slirp *slirp_init(int restricted, bool in_enabled, struct in_addr vnetwork,
                   const char *vhostname, const char *tftp_path,
                   const char *bootfile, struct in_addr vdhcp_start,
                   struct in_addr vnameserver, struct in6_addr vnameserver6,
-                  const char **vdnssearch, void *opaque)
+                  const char **vdnssearch, const char *vdomainname,
+                  void *opaque)
 {
     Slirp *slirp = g_malloc0(sizeof(Slirp));
 
@@ -315,6 +316,7 @@ Slirp *slirp_init(int restricted, bool in_enabled, struct in_addr vnetwork,
     }
     slirp->tftp_prefix = g_strdup(tftp_path);
     slirp->bootp_filename = g_strdup(bootfile);
+    slirp->vdomainname = g_strdup(vdomainname);
     slirp->vdhcp_startaddr = vdhcp_start;
     slirp->vnameserver_addr = vnameserver;
     slirp->vnameserver_addr6 = vnameserver6;
@@ -347,6 +349,7 @@ void slirp_cleanup(Slirp *slirp)
     g_free(slirp->vdnssearch);
     g_free(slirp->tftp_prefix);
     g_free(slirp->bootp_filename);
+    g_free(slirp->vdomainname);
     g_free(slirp);
 }
 
diff --git a/slirp.h b/slirp.h
index 049da65..318bd52 100644
--- a/slirp.h
+++ b/slirp.h
@@ -193,6 +193,7 @@ struct Slirp {
     char *bootp_filename;
     size_t vdnssearch_len;
     uint8_t *vdnssearch;
+    char *vdomainname;
 
     /* tcp states */
     struct socket tcb;