[PATCH] DHCPv6: Fix prefix delegation lease file name

Cherry-picked from
https://chromium.googlesource.com/chromiumos/overlays/chromiumos-overlay/+/
master/net-misc/dhcpcd/files/patches/dhcpcd-6.8.2-DHCPv6-Fix-prefix-
delegation-lease-file-name.patch.

For DHCPv6, daemon creates two lease files, one for non-temporary
address and the other for prefix delegation. Currently only non-temporary
address lease is using the lease identifier obtained from command line
for its file name, since dhcpcd is using a separate pseudo interface
for handling prefix delegation messages.

So fix it to have both lease files using the same identifier obtained
from the command line, with non-temporary address lease ends in ".lease6"
and prefix delegation ends is ".pd.lease6".

BUG: 22956197
Change-Id: I24ada24e791e0be77aaadd148349be00ef2b6966

Reviewed-on: https://chromium-review.googlesource.com/282041

2 files changed, 10 insertions, 2 deletions

diff --git a/dhcp-common.c b/dhcp-common.c
index 9ac226a..a3764f1 100644
--- a/dhcp-common.c
+++ b/dhcp-common.c
@@ -750,11 +750,11 @@ dhcp_set_leasefile(char *leasefile, size_t len, int family,
 	if (strlen(ifp->lease_identifier) > 0) {
 		return snprintf(leasefile, len,
 				family == AF_INET ? LEASEFILE : LEASEFILE6,
-				ifp->lease_identifier, "", "");
+				ifp->lease_identifier, "", extra);
 	}
 	return snprintf(leasefile, len,
 			family == AF_INET ? LEASEFILE : LEASEFILE6,
-			ifp->name, "", "");
+			ifp->name, "", extra);
 }
 
 static size_t
diff --git a/dhcp6.c b/dhcp6.c
index 79b7cf1..238acd4 100644
--- a/dhcp6.c
+++ b/dhcp6.c
@@ -3207,6 +3207,14 @@ dhcp6_start1(void *arg)
 					    ifp->name);
 					ifp->options->options |=
 					    DHCPCD_NOPFXDLG;
+					/*
+					 * Maintain the same lease identifier
+					 * for the pseudo interface for
+					 * obtaining prefix delegation.
+					 */
+					strlcpy(ifn->lease_identifier,
+					        ifp->lease_identifier,
+					        sizeof(ifn->lease_identifier));
 					TAILQ_REMOVE(ifs, ifn, next);
 					TAILQ_INSERT_AFTER(ifp->ctx->ifaces,
 					    ifp, ifn, next);