This is an adaptation of zero_out_mutable_opts that takes three
additional arguments: offset of the TLVs, a mask to locate the
mutable bit in the TLV type, and the type value for single byte
padding.
zero_out_mutable_opts calls the new function and sets the arguments
appropriate to Hop-by-Hop and Destination Options. The function will
be used to support zeroing out mutable SRH TLVs' data with the
appropriate arguments for SRH TLVs.
Signed-off-by: Tom Herbert <t...@quantonium.net>
---
net/ipv6/ah6.c | 29 +++++++++++++++--------------
1 file changed, 15 insertions(+), 14 deletions(-)
diff --git a/net/ipv6/ah6.c b/net/ipv6/ah6.c
index 68b9e92..1e80157 100644
--- a/net/ipv6/ah6.c
+++ b/net/ipv6/ah6.c
@@ -102,32 +102,28 @@ static inline struct scatterlist *ah_req_sg(struct
crypto_ahash *ahash,
__alignof__(struct scatterlist));
}
-static bool zero_out_mutable_opts(struct ipv6_opt_hdr *opthdr)
+static bool __zero_out_mutable_opts(struct ipv6_opt_hdr *opthdr, int off,
+ unsigned char mut_bit, unsigned char pad1)
{
u8 *opt = (u8 *)opthdr;
int len = ipv6_optlen(opthdr);
- int off = 0;
int optlen = 0;
- off += 2;
- len -= 2;
+ len -= off;
while (len > 0) {
-
- switch (opt[off]) {
-
- case IPV6_TLV_PAD1:
+ if (opt[off] == pad1) {
optlen = 1;
- break;
- default:
+ } else {
if (len < 2)
goto bad;
- optlen = opt[off+1]+2;
+
+ optlen = opt[off + 1] + 2;
if (len < optlen)
goto bad;
- if (opt[off] & 0x20)
- memset(&opt[off+2], 0, opt[off+1]);
- break;
+
+ if (opt[off] & mut_bit)
+ memset(&opt[off + 2], 0, opt[off + 1]);
}
off += optlen;
@@ -140,6 +136,11 @@ static bool zero_out_mutable_opts(struct ipv6_opt_hdr
*opthdr)
return false;
}
+static bool zero_out_mutable_opts(struct ipv6_opt_hdr *opthdr)
+{
+ return __zero_out_mutable_opts(opthdr, 2, 0x20, IPV6_TLV_PAD1);
+}
+
#if IS_ENABLED(CONFIG_IPV6_MIP6)
/**
* ipv6_rearrange_destopt - rearrange IPv6 destination options header
--
2.7.4
