udhcpc: add a cooment about sanitizing DHCP_DOMAIN_NAME, no code changes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/networking/udhcp/dhcpc.c b/networking/udhcp/dhcpc.c
index 3afdb35fe..0310663e0 100644
--- a/networking/udhcp/dhcpc.c
+++ b/networking/udhcp/dhcpc.c
@@ -274,6 +274,12 @@ static NOINLINE char *xmalloc_optname_optval(uint8_t *option, const struct dhcp_
                 case OPTION_STRING_HOST:
                         memcpy(dest, option, len);
                         dest[len] = '\0';
+//TODO: it appears option 15 DHCP_DOMAIN_NAME is often abused
+//by DHCP admins to contain a space-separated list of domains,
+//not one domain name (presumably, to work as list of search domains,
+//instead of using proper option 119 DHCP_DOMAIN_SEARCH).
+//Currently, good_hostname() balks on strings containing spaces.
+//Do we need to allow it? Only for DHCP_DOMAIN_NAME option?
                         if (type == OPTION_STRING_HOST && !good_hostname(dest))
                                 safe_strncpy(dest, "bad", len);
                         return ret;