busybox: add 6RD prefix sanity checking as mandated by RFC5969, bump pkg revision

SVN-Revision: 23990
This commit is contained in:
Jo-Philipp Wich 2010-11-14 05:58:34 +00:00
parent 9efe60a464
commit e3f13f0141
2 changed files with 37 additions and 27 deletions

View file

@ -9,7 +9,7 @@ include $(TOPDIR)/rules.mk
PKG_NAME:=busybox
PKG_VERSION:=1.17.3
PKG_RELEASE:=1
PKG_RELEASE:=2
PKG_FLAGS:=essential
PKG_SOURCE:=$(PKG_NAME)-$(PKG_VERSION).tar.bz2

View file

@ -58,7 +58,7 @@
/* really simple implementation, just count the bits */
static int mton(uint32_t mask)
{
@@ -177,6 +195,60 @@ static NOINLINE char *xmalloc_optname_op
@@ -177,6 +195,70 @@ static NOINLINE char *xmalloc_optname_op
return ret;
}
@ -85,33 +85,43 @@
+ * We convert it to a string "IPv4MaskLen 6rdPrefixLen 6rdPrefix 6rdBRIPv4Address"
+ */
+
+ /* IPv4MaskLen */
+ dest += sprintf(dest, "%u ", *option++);
+ len--;
+
+ /* 6rdPrefixLen */
+ dest += sprintf(dest, "%u ", *option++);
+ len--;
+
+ /* 6rdPrefix */
+ dest += sprint_nip6(dest, "", option);
+ option += 16;
+ len -= 16;
+
+ /* 6rdBRIPv4Addresses */
+ while (len >= 4)
+ /* Sanity check: ensure that our length is at least 22 bytes, that
+ * IPv4MaskLen is <= 32, 6rdPrefixLen <= 128 and that the sum of
+ * (32 - IPv4MaskLen) + 6rdPrefixLen is less than or equal to 128.
+ * If any of these requirements is not fulfilled, return with empty
+ * value.
+ */
+ if ((len >= 22) && (*option <= 32) && (*(option+1) <= 128) &&
+ (((32 - *option) + *(option+1)) <= 128))
+ {
+ dest += sprint_nip(dest, " ", option);
+ option += 4;
+ len -= 4;
+ /* IPv4MaskLen */
+ dest += sprintf(dest, "%u ", *option++);
+ len--;
+
+ /* the code to determine the option size fails to work with
+ * lengths that are not a multiple of the minimum length,
+ * adding all advertised 6rdBRIPv4Addresses here would
+ * overflow the destination buffer, therefore skip the rest
+ * for now
+ */
+ break;
+ /* 6rdPrefixLen */
+ dest += sprintf(dest, "%u ", *option++);
+ len--;
+
+ /* 6rdPrefix */
+ dest += sprint_nip6(dest, "", option);
+ option += 16;
+ len -= 16;
+
+ /* 6rdBRIPv4Addresses */
+ while (len >= 4)
+ {
+ dest += sprint_nip(dest, " ", option);
+ option += 4;
+ len -= 4;
+
+ /* the code to determine the option size fails to work with
+ * lengths that are not a multiple of the minimum length,
+ * adding all advertised 6rdBRIPv4Addresses here would
+ * overflow the destination buffer, therefore skip the rest
+ * for now
+ */
+ break;
+ }
+ }
+
+ return ret;