For review:
The purpose of this series is to get the Linux NFS server's
duplicate reply cache working again when the server is mounted via
krb5p. Thus I would like to send these three commits via an
nfsd-5.7-rc pull request in a couple of weeks, depending on review
comments.
The second patch is strictly a client-side fix, but it is necessary
because the third patch causes problems on the client unless the
first and second patches are applied first. Being a client-side
change, the second patch needs an Acked-by from Trond or Anna so I
can send a PR via the NFSD tree.
I've tested this series by running "make -j12 test" in a freshly-
built git source tree on an NFS mount. The test was run on a
sequence of mounts using every combination of:
- TCP and RDMA
- NFSv3, NFSv4.0, NFSv4.1, and NFSv4.1
- krb5p with a kerberos_v1 and kerberos_v2 encryption type
For RDMA in particular, frequent GSS sequence number window overruns
make the transport connection unstable -- typically over 3,000
disconnects for a test run that takes about 30 minutes. A
successful test run on an NFSv3 or NFSv4.0 mount point is therefore
enough to demonstrate that the server's DRC is working properly.
NFSv4.1+ is also tested to show that krb5p continues to work
correctly for NFS minor versions that do not happen to use the
server's DRC.
---
Chuck Lever (3):
SUNRPC: Add "@len" parameter to gss_unwrap()
SUNRPC: Fix GSS privacy computation of auth->au_ralign
SUNRPC: Revert 241b1f419f0e ("SUNRPC: Remove xdr_buf_trim()")
include/linux/sunrpc/gss_api.h | 1 +
include/linux/sunrpc/xdr.h | 1 +
net/sunrpc/auth_gss/auth_gss.c | 8 +++-----
net/sunrpc/auth_gss/gss_krb5_wrap.c | 26 +++++++++++++++--------
net/sunrpc/auth_gss/svcauth_gss.c | 2 +-
net/sunrpc/xdr.c | 41 +++++++++++++++++++++++++++++++++++++
6 files changed, 65 insertions(+), 14 deletions(-)
--
Chuck Lever
Refactor: This is a pre-requisite to fixing the client-side ralign
computation in gss_unwrap_resp_priv().
The length value is passed in explicitly rather that as the value
of buf->len. This will subsequently allow gss_unwrap_kerberos_v1()
to compute a slack and align value, instead of computing it in
gss_unwrap_resp_priv().
Fixes: 35e77d21baa0 ("SUNRPC: Add rpc_auth::au_ralign field")
Signed-off-by: Chuck Lever <[email protected]>
---
include/linux/sunrpc/gss_api.h | 2 ++
include/linux/sunrpc/gss_krb5.h | 6 +++---
net/sunrpc/auth_gss/auth_gss.c | 4 ++--
net/sunrpc/auth_gss/gss_krb5_crypto.c | 8 ++++----
net/sunrpc/auth_gss/gss_krb5_wrap.c | 26 +++++++++++++++-----------
net/sunrpc/auth_gss/gss_mech_switch.c | 3 ++-
net/sunrpc/auth_gss/svcauth_gss.c | 8 ++------
7 files changed, 30 insertions(+), 27 deletions(-)
diff --git a/include/linux/sunrpc/gss_api.h b/include/linux/sunrpc/gss_api.h
index 48c1b1674cbf..e9a79518d652 100644
--- a/include/linux/sunrpc/gss_api.h
+++ b/include/linux/sunrpc/gss_api.h
@@ -66,6 +66,7 @@ u32 gss_wrap(
u32 gss_unwrap(
struct gss_ctx *ctx_id,
int offset,
+ int len,
struct xdr_buf *inbuf);
u32 gss_delete_sec_context(
struct gss_ctx **ctx_id);
@@ -126,6 +127,7 @@ struct gss_api_ops {
u32 (*gss_unwrap)(
struct gss_ctx *ctx_id,
int offset,
+ int len,
struct xdr_buf *buf);
void (*gss_delete_sec_context)(
void *internal_ctx_id);
diff --git a/include/linux/sunrpc/gss_krb5.h b/include/linux/sunrpc/gss_krb5.h
index c1d77dd8ed41..e8f8ffe7448b 100644
--- a/include/linux/sunrpc/gss_krb5.h
+++ b/include/linux/sunrpc/gss_krb5.h
@@ -83,7 +83,7 @@ struct gss_krb5_enctype {
u32 (*encrypt_v2) (struct krb5_ctx *kctx, u32 offset,
struct xdr_buf *buf,
struct page **pages); /* v2 encryption function */
- u32 (*decrypt_v2) (struct krb5_ctx *kctx, u32 offset,
+ u32 (*decrypt_v2) (struct krb5_ctx *kctx, u32 offset, u32 len,
struct xdr_buf *buf, u32 *headskip,
u32 *tailskip); /* v2 decryption function */
};
@@ -255,7 +255,7 @@ gss_wrap_kerberos(struct gss_ctx *ctx_id, int offset,
struct xdr_buf *outbuf, struct page **pages);
u32
-gss_unwrap_kerberos(struct gss_ctx *ctx_id, int offset,
+gss_unwrap_kerberos(struct gss_ctx *ctx_id, int offset, int len,
struct xdr_buf *buf);
@@ -312,7 +312,7 @@ gss_krb5_aes_encrypt(struct krb5_ctx *kctx, u32 offset,
struct page **pages);
u32
-gss_krb5_aes_decrypt(struct krb5_ctx *kctx, u32 offset,
+gss_krb5_aes_decrypt(struct krb5_ctx *kctx, u32 offset, u32 len,
struct xdr_buf *buf, u32 *plainoffset,
u32 *plainlen);
diff --git a/net/sunrpc/auth_gss/auth_gss.c b/net/sunrpc/auth_gss/auth_gss.c
index 25fbd8d9de74..7885f37e3688 100644
--- a/net/sunrpc/auth_gss/auth_gss.c
+++ b/net/sunrpc/auth_gss/auth_gss.c
@@ -2043,9 +2043,9 @@ gss_unwrap_resp_priv(struct rpc_task *task, struct rpc_cred *cred,
offset = (u8 *)(p) - (u8 *)head->iov_base;
if (offset + opaque_len > rcv_buf->len)
goto unwrap_failed;
- rcv_buf->len = offset + opaque_len;
- maj_stat = gss_unwrap(ctx->gc_gss_ctx, offset, rcv_buf);
+ maj_stat = gss_unwrap(ctx->gc_gss_ctx, offset,
+ offset + opaque_len, rcv_buf);
if (maj_stat == GSS_S_CONTEXT_EXPIRED)
clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
if (maj_stat != GSS_S_COMPLETE)
diff --git a/net/sunrpc/auth_gss/gss_krb5_crypto.c b/net/sunrpc/auth_gss/gss_krb5_crypto.c
index 6f2d30d7b766..e7180da1fc6a 100644
--- a/net/sunrpc/auth_gss/gss_krb5_crypto.c
+++ b/net/sunrpc/auth_gss/gss_krb5_crypto.c
@@ -851,8 +851,8 @@ gss_krb5_aes_encrypt(struct krb5_ctx *kctx, u32 offset,
}
u32
-gss_krb5_aes_decrypt(struct krb5_ctx *kctx, u32 offset, struct xdr_buf *buf,
- u32 *headskip, u32 *tailskip)
+gss_krb5_aes_decrypt(struct krb5_ctx *kctx, u32 offset, u32 len,
+ struct xdr_buf *buf, u32 *headskip, u32 *tailskip)
{
struct xdr_buf subbuf;
u32 ret = 0;
@@ -881,7 +881,7 @@ gss_krb5_aes_decrypt(struct krb5_ctx *kctx, u32 offset, struct xdr_buf *buf,
/* create a segment skipping the header and leaving out the checksum */
xdr_buf_subsegment(buf, &subbuf, offset + GSS_KRB5_TOK_HDR_LEN,
- (buf->len - offset - GSS_KRB5_TOK_HDR_LEN -
+ (len - offset - GSS_KRB5_TOK_HDR_LEN -
kctx->gk5e->cksumlength));
nblocks = (subbuf.len + blocksize - 1) / blocksize;
@@ -926,7 +926,7 @@ gss_krb5_aes_decrypt(struct krb5_ctx *kctx, u32 offset, struct xdr_buf *buf,
goto out_err;
/* Get the packet's hmac value */
- ret = read_bytes_from_xdr_buf(buf, buf->len - kctx->gk5e->cksumlength,
+ ret = read_bytes_from_xdr_buf(buf, len - kctx->gk5e->cksumlength,
pkt_hmac, kctx->gk5e->cksumlength);
if (ret)
goto out_err;
diff --git a/net/sunrpc/auth_gss/gss_krb5_wrap.c b/net/sunrpc/auth_gss/gss_krb5_wrap.c
index 6c1920eed771..c7589e35d5d9 100644
--- a/net/sunrpc/auth_gss/gss_krb5_wrap.c
+++ b/net/sunrpc/auth_gss/gss_krb5_wrap.c
@@ -261,7 +261,8 @@ gss_wrap_kerberos_v1(struct krb5_ctx *kctx, int offset,
}
static u32
-gss_unwrap_kerberos_v1(struct krb5_ctx *kctx, int offset, struct xdr_buf *buf)
+gss_unwrap_kerberos_v1(struct krb5_ctx *kctx, int offset, int len,
+ struct xdr_buf *buf)
{
int signalg;
int sealalg;
@@ -284,7 +285,7 @@ gss_unwrap_kerberos_v1(struct krb5_ctx *kctx, int offset, struct xdr_buf *buf)
ptr = (u8 *)buf->head[0].iov_base + offset;
if (g_verify_token_header(&kctx->mech_used, &bodysize, &ptr,
- buf->len - offset))
+ len - offset))
return GSS_S_DEFECTIVE_TOKEN;
if ((ptr[0] != ((KG_TOK_WRAP_MSG >> 8) & 0xff)) ||
@@ -324,6 +325,7 @@ gss_unwrap_kerberos_v1(struct krb5_ctx *kctx, int offset, struct xdr_buf *buf)
(!kctx->initiate && direction != 0))
return GSS_S_BAD_SIG;
+ buf->len = len;
if (kctx->enctype == ENCTYPE_ARCFOUR_HMAC) {
struct crypto_sync_skcipher *cipher;
int err;
@@ -376,7 +378,7 @@ gss_unwrap_kerberos_v1(struct krb5_ctx *kctx, int offset, struct xdr_buf *buf)
data_len = (buf->head[0].iov_base + buf->head[0].iov_len) - data_start;
memmove(orig_start, data_start, data_len);
buf->head[0].iov_len -= (data_start - orig_start);
- buf->len -= (data_start - orig_start);
+ buf->len = len - (data_start - orig_start);
if (gss_krb5_remove_padding(buf, blocksize))
return GSS_S_DEFECTIVE_TOKEN;
@@ -486,7 +488,8 @@ gss_wrap_kerberos_v2(struct krb5_ctx *kctx, u32 offset,
}
static u32
-gss_unwrap_kerberos_v2(struct krb5_ctx *kctx, int offset, struct xdr_buf *buf)
+gss_unwrap_kerberos_v2(struct krb5_ctx *kctx, int offset, int len,
+ struct xdr_buf *buf)
{
time64_t now;
u8 *ptr;
@@ -532,7 +535,7 @@ gss_unwrap_kerberos_v2(struct krb5_ctx *kctx, int offset, struct xdr_buf *buf)
if (rrc != 0)
rotate_left(offset + 16, buf, rrc);
- err = (*kctx->gk5e->decrypt_v2)(kctx, offset, buf,
+ err = (*kctx->gk5e->decrypt_v2)(kctx, offset, len, buf,
&headskip, &tailskip);
if (err)
return GSS_S_FAILURE;
@@ -542,7 +545,7 @@ gss_unwrap_kerberos_v2(struct krb5_ctx *kctx, int offset, struct xdr_buf *buf)
* it against the original
*/
err = read_bytes_from_xdr_buf(buf,
- buf->len - GSS_KRB5_TOK_HDR_LEN - tailskip,
+ len - GSS_KRB5_TOK_HDR_LEN - tailskip,
decrypted_hdr, GSS_KRB5_TOK_HDR_LEN);
if (err) {
dprintk("%s: error %u getting decrypted_hdr\n", __func__, err);
@@ -568,14 +571,14 @@ gss_unwrap_kerberos_v2(struct krb5_ctx *kctx, int offset, struct xdr_buf *buf)
* Note that buf->head[0].iov_len may indicate the available
* head buffer space rather than that actually occupied.
*/
- movelen = min_t(unsigned int, buf->head[0].iov_len, buf->len);
+ movelen = min_t(unsigned int, buf->head[0].iov_len, len);
movelen -= offset + GSS_KRB5_TOK_HDR_LEN + headskip;
if (offset + GSS_KRB5_TOK_HDR_LEN + headskip + movelen >
buf->head[0].iov_len)
return GSS_S_FAILURE;
memmove(ptr, ptr + GSS_KRB5_TOK_HDR_LEN + headskip, movelen);
buf->head[0].iov_len -= GSS_KRB5_TOK_HDR_LEN + headskip;
- buf->len -= GSS_KRB5_TOK_HDR_LEN + headskip;
+ buf->len = len - GSS_KRB5_TOK_HDR_LEN + headskip;
/* Trim off the trailing "extra count" and checksum blob */
buf->len -= ec + GSS_KRB5_TOK_HDR_LEN + tailskip;
@@ -603,7 +606,8 @@ gss_wrap_kerberos(struct gss_ctx *gctx, int offset,
}
u32
-gss_unwrap_kerberos(struct gss_ctx *gctx, int offset, struct xdr_buf *buf)
+gss_unwrap_kerberos(struct gss_ctx *gctx, int offset,
+ int len, struct xdr_buf *buf)
{
struct krb5_ctx *kctx = gctx->internal_ctx_id;
@@ -613,9 +617,9 @@ gss_unwrap_kerberos(struct gss_ctx *gctx, int offset, struct xdr_buf *buf)
case ENCTYPE_DES_CBC_RAW:
case ENCTYPE_DES3_CBC_RAW:
case ENCTYPE_ARCFOUR_HMAC:
- return gss_unwrap_kerberos_v1(kctx, offset, buf);
+ return gss_unwrap_kerberos_v1(kctx, offset, len, buf);
case ENCTYPE_AES128_CTS_HMAC_SHA1_96:
case ENCTYPE_AES256_CTS_HMAC_SHA1_96:
- return gss_unwrap_kerberos_v2(kctx, offset, buf);
+ return gss_unwrap_kerberos_v2(kctx, offset, len, buf);
}
}
diff --git a/net/sunrpc/auth_gss/gss_mech_switch.c b/net/sunrpc/auth_gss/gss_mech_switch.c
index db550bfc2642..69316ab1b9fa 100644
--- a/net/sunrpc/auth_gss/gss_mech_switch.c
+++ b/net/sunrpc/auth_gss/gss_mech_switch.c
@@ -411,10 +411,11 @@ gss_wrap(struct gss_ctx *ctx_id,
u32
gss_unwrap(struct gss_ctx *ctx_id,
int offset,
+ int len,
struct xdr_buf *buf)
{
return ctx_id->mech_type->gm_ops
- ->gss_unwrap(ctx_id, offset, buf);
+ ->gss_unwrap(ctx_id, offset, len, buf);
}
diff --git a/net/sunrpc/auth_gss/svcauth_gss.c b/net/sunrpc/auth_gss/svcauth_gss.c
index 54ae5be62f6a..d0a2f084e5a4 100644
--- a/net/sunrpc/auth_gss/svcauth_gss.c
+++ b/net/sunrpc/auth_gss/svcauth_gss.c
@@ -934,7 +934,7 @@ static int
unwrap_priv_data(struct svc_rqst *rqstp, struct xdr_buf *buf, u32 seq, struct gss_ctx *ctx)
{
u32 priv_len, maj_stat;
- int pad, saved_len, remaining_len, offset;
+ int pad, remaining_len, offset;
clear_bit(RQ_SPLICE_OK, &rqstp->rq_flags);
@@ -954,12 +954,8 @@ unwrap_priv_data(struct svc_rqst *rqstp, struct xdr_buf *buf, u32 seq, struct gs
buf->len -= pad;
fix_priv_head(buf, pad);
- /* Maybe it would be better to give gss_unwrap a length parameter: */
- saved_len = buf->len;
- buf->len = priv_len;
- maj_stat = gss_unwrap(ctx, 0, buf);
+ maj_stat = gss_unwrap(ctx, 0, priv_len, buf);
pad = priv_len - buf->len;
- buf->len = saved_len;
buf->len -= pad;
/* The upper layers assume the buffer is aligned on 4-byte boundaries.
* In the krb5p case, at least, the data ends up offset, so we need to
I've noticed that when krb5i or krb5p security is in use,
retransmitted requests are missing the server's duplicate reply
cache. The computed checksum on the retransmitted request does not
match the cached checksum, resulting in the server performing the
retransmitted request again instead of returning the cached reply.
The assumptions made when removing xdr_buf_trim() were not correct.
In the send paths, the upper layer has already set the segment
lengths correctly, and shorting the buffer's content is simply a
matter of reducing buf->len.
xdr_buf_trim() is the right answer in the receive/unwrap path on
both the client and the server. The buffer segment lengths have to
be shortened one-by-one.
On the server side in particular, head.iov_len needs to be updated
correctly to enable nfsd_cache_csum() to work correctly. The simple
buf->len computation doesn't do that, and that results in
checksumming stale data in the buffer.
The problem isn't noticed until there's significant instability of
the RPC transport. At that point, the reliability of retransmit
detection on the server becomes crucial.
Fixes: 241b1f419f0e ("SUNRPC: Remove xdr_buf_trim()")
Signed-off-by: Chuck Lever <[email protected]>
---
include/linux/sunrpc/xdr.h | 1 +
net/sunrpc/auth_gss/gss_krb5_wrap.c | 7 +++---
net/sunrpc/auth_gss/svcauth_gss.c | 2 +-
net/sunrpc/xdr.c | 41 +++++++++++++++++++++++++++++++++++
4 files changed, 46 insertions(+), 5 deletions(-)
diff --git a/include/linux/sunrpc/xdr.h b/include/linux/sunrpc/xdr.h
index 01bb41908c93..22c207b2425f 100644
--- a/include/linux/sunrpc/xdr.h
+++ b/include/linux/sunrpc/xdr.h
@@ -184,6 +184,7 @@ xdr_adjust_iovec(struct kvec *iov, __be32 *p)
extern void xdr_shift_buf(struct xdr_buf *, size_t);
extern void xdr_buf_from_iov(struct kvec *, struct xdr_buf *);
extern int xdr_buf_subsegment(struct xdr_buf *, struct xdr_buf *, unsigned int, unsigned int);
+extern void xdr_buf_trim(struct xdr_buf *, unsigned int);
extern int read_bytes_from_xdr_buf(struct xdr_buf *, unsigned int, void *, unsigned int);
extern int write_bytes_to_xdr_buf(struct xdr_buf *, unsigned int, void *, unsigned int);
diff --git a/net/sunrpc/auth_gss/gss_krb5_wrap.c b/net/sunrpc/auth_gss/gss_krb5_wrap.c
index 4905652e7567..cf0fd170ac18 100644
--- a/net/sunrpc/auth_gss/gss_krb5_wrap.c
+++ b/net/sunrpc/auth_gss/gss_krb5_wrap.c
@@ -580,15 +580,14 @@ gss_unwrap_kerberos_v2(struct krb5_ctx *kctx, int offset, int len,
*/
movelen = min_t(unsigned int, buf->head[0].iov_len, len);
movelen -= offset + GSS_KRB5_TOK_HDR_LEN + headskip;
- if (offset + GSS_KRB5_TOK_HDR_LEN + headskip + movelen >
- buf->head[0].iov_len)
- return GSS_S_FAILURE;
+ BUG_ON(offset + GSS_KRB5_TOK_HDR_LEN + headskip + movelen >
+ buf->head[0].iov_len);
memmove(ptr, ptr + GSS_KRB5_TOK_HDR_LEN + headskip, movelen);
buf->head[0].iov_len -= GSS_KRB5_TOK_HDR_LEN + headskip;
buf->len = len - GSS_KRB5_TOK_HDR_LEN + headskip;
/* Trim off the trailing "extra count" and checksum blob */
- buf->len -= ec + GSS_KRB5_TOK_HDR_LEN + tailskip;
+ xdr_buf_trim(buf, ec + GSS_KRB5_TOK_HDR_LEN + tailskip);
*align = XDR_QUADLEN(GSS_KRB5_TOK_HDR_LEN + headskip);
*slack = *align + XDR_QUADLEN(ec + GSS_KRB5_TOK_HDR_LEN + tailskip);
diff --git a/net/sunrpc/auth_gss/svcauth_gss.c b/net/sunrpc/auth_gss/svcauth_gss.c
index d0a2f084e5a4..50d93c49ef1a 100644
--- a/net/sunrpc/auth_gss/svcauth_gss.c
+++ b/net/sunrpc/auth_gss/svcauth_gss.c
@@ -906,7 +906,7 @@ unwrap_integ_data(struct svc_rqst *rqstp, struct xdr_buf *buf, u32 seq, struct g
if (svc_getnl(&buf->head[0]) != seq)
goto out;
/* trim off the mic and padding at the end before returning */
- buf->len -= 4 + round_up_to_quad(mic.len);
+ xdr_buf_trim(buf, round_up_to_quad(mic.len) + 4);
stat = 0;
out:
kfree(mic.data);
diff --git a/net/sunrpc/xdr.c b/net/sunrpc/xdr.c
index 15b58c5144f9..6f7d82fb1eb0 100644
--- a/net/sunrpc/xdr.c
+++ b/net/sunrpc/xdr.c
@@ -1150,6 +1150,47 @@ xdr_buf_subsegment(struct xdr_buf *buf, struct xdr_buf *subbuf,
}
EXPORT_SYMBOL_GPL(xdr_buf_subsegment);
+/**
+ * xdr_buf_trim - lop at most "len" bytes off the end of "buf"
+ * @buf: buf to be trimmed
+ * @len: number of bytes to reduce "buf" by
+ *
+ * Trim an xdr_buf by the given number of bytes by fixing up the lengths. Note
+ * that it's possible that we'll trim less than that amount if the xdr_buf is
+ * too small, or if (for instance) it's all in the head and the parser has
+ * already read too far into it.
+ */
+void xdr_buf_trim(struct xdr_buf *buf, unsigned int len)
+{
+ size_t cur;
+ unsigned int trim = len;
+
+ if (buf->tail[0].iov_len) {
+ cur = min_t(size_t, buf->tail[0].iov_len, trim);
+ buf->tail[0].iov_len -= cur;
+ trim -= cur;
+ if (!trim)
+ goto fix_len;
+ }
+
+ if (buf->page_len) {
+ cur = min_t(unsigned int, buf->page_len, trim);
+ buf->page_len -= cur;
+ trim -= cur;
+ if (!trim)
+ goto fix_len;
+ }
+
+ if (buf->head[0].iov_len) {
+ cur = min_t(size_t, buf->head[0].iov_len, trim);
+ buf->head[0].iov_len -= cur;
+ trim -= cur;
+ }
+fix_len:
+ buf->len -= (len - trim);
+}
+EXPORT_SYMBOL_GPL(xdr_buf_trim);
+
static void __read_bytes_from_xdr_buf(struct xdr_buf *subbuf, void *obj, unsigned int len)
{
unsigned int this_len;
When the au_ralign field was added to gss_unwrap_resp_priv, the
wrong calculation was used. Setting au_rslack == au_ralign is
probably correct for kerberos_v1 privacy, but kerberos_v2 privacy
adds additional GSS data after the clear text RPC message.
au_ralign needs to be smaller than au_rslack in that fairly common
case.
When xdr_buf_trim() is restored to gss_unwrap_kerberos_v2(), it does
exactly what I feared it would: it trims off part of the clear text
RPC message. However, that's because rpc_prepare_reply_pages() does
not set up the rq_rcv_buf's tail correctly because au_ralign is too
large.
Fixing the au_ralign computation also corrects the alignment of
rq_rcv_buf->pages so that the client does not have to shift reply
data payloads after they are received.
Fixes: 35e77d21baa0 ("SUNRPC: Add rpc_auth::au_ralign field")
Signed-off-by: Chuck Lever <[email protected]>
---
include/linux/sunrpc/gss_api.h | 1 +
net/sunrpc/auth_gss/auth_gss.c | 8 +++-----
net/sunrpc/auth_gss/gss_krb5_wrap.c | 19 +++++++++++++++----
3 files changed, 19 insertions(+), 9 deletions(-)
diff --git a/include/linux/sunrpc/gss_api.h b/include/linux/sunrpc/gss_api.h
index e9a79518d652..bc07e51f20d1 100644
--- a/include/linux/sunrpc/gss_api.h
+++ b/include/linux/sunrpc/gss_api.h
@@ -21,6 +21,7 @@
struct gss_ctx {
struct gss_api_mech *mech_type;
void *internal_ctx_id;
+ unsigned int slack, align;
};
#define GSS_C_NO_BUFFER ((struct xdr_netobj) 0)
diff --git a/net/sunrpc/auth_gss/auth_gss.c b/net/sunrpc/auth_gss/auth_gss.c
index 7885f37e3688..ac5cac0dd24b 100644
--- a/net/sunrpc/auth_gss/auth_gss.c
+++ b/net/sunrpc/auth_gss/auth_gss.c
@@ -2032,7 +2032,6 @@ gss_unwrap_resp_priv(struct rpc_task *task, struct rpc_cred *cred,
struct xdr_buf *rcv_buf = &rqstp->rq_rcv_buf;
struct kvec *head = rqstp->rq_rcv_buf.head;
struct rpc_auth *auth = cred->cr_auth;
- unsigned int savedlen = rcv_buf->len;
u32 offset, opaque_len, maj_stat;
__be32 *p;
@@ -2059,10 +2058,9 @@ gss_unwrap_resp_priv(struct rpc_task *task, struct rpc_cred *cred,
*/
xdr_init_decode(xdr, rcv_buf, p, rqstp);
- auth->au_rslack = auth->au_verfsize + 2 +
- XDR_QUADLEN(savedlen - rcv_buf->len);
- auth->au_ralign = auth->au_verfsize + 2 +
- XDR_QUADLEN(savedlen - rcv_buf->len);
+ auth->au_rslack = auth->au_verfsize + 2 + ctx->gc_gss_ctx->slack;
+ auth->au_ralign = auth->au_verfsize + 2 + ctx->gc_gss_ctx->align;
+
return 0;
unwrap_failed:
trace_rpcgss_unwrap_failed(task);
diff --git a/net/sunrpc/auth_gss/gss_krb5_wrap.c b/net/sunrpc/auth_gss/gss_krb5_wrap.c
index c7589e35d5d9..4905652e7567 100644
--- a/net/sunrpc/auth_gss/gss_krb5_wrap.c
+++ b/net/sunrpc/auth_gss/gss_krb5_wrap.c
@@ -262,7 +262,8 @@ gss_wrap_kerberos_v1(struct krb5_ctx *kctx, int offset,
static u32
gss_unwrap_kerberos_v1(struct krb5_ctx *kctx, int offset, int len,
- struct xdr_buf *buf)
+ struct xdr_buf *buf, unsigned int *slack,
+ unsigned int *align)
{
int signalg;
int sealalg;
@@ -280,6 +281,7 @@ gss_unwrap_kerberos_v1(struct krb5_ctx *kctx, int offset, int len,
u32 conflen = kctx->gk5e->conflen;
int crypt_offset;
u8 *cksumkey;
+ unsigned int saved_len = buf->len;
dprintk("RPC: gss_unwrap_kerberos\n");
@@ -383,6 +385,10 @@ gss_unwrap_kerberos_v1(struct krb5_ctx *kctx, int offset, int len,
if (gss_krb5_remove_padding(buf, blocksize))
return GSS_S_DEFECTIVE_TOKEN;
+ /* slack must include room for krb5 padding */
+ *slack = XDR_QUADLEN(saved_len - buf->len);
+ /* The GSS blob always precedes the RPC message payload */
+ *align = *slack;
return GSS_S_COMPLETE;
}
@@ -489,7 +495,8 @@ gss_wrap_kerberos_v2(struct krb5_ctx *kctx, u32 offset,
static u32
gss_unwrap_kerberos_v2(struct krb5_ctx *kctx, int offset, int len,
- struct xdr_buf *buf)
+ struct xdr_buf *buf, unsigned int *slack,
+ unsigned int *align)
{
time64_t now;
u8 *ptr;
@@ -583,6 +590,8 @@ gss_unwrap_kerberos_v2(struct krb5_ctx *kctx, int offset, int len,
/* Trim off the trailing "extra count" and checksum blob */
buf->len -= ec + GSS_KRB5_TOK_HDR_LEN + tailskip;
+ *align = XDR_QUADLEN(GSS_KRB5_TOK_HDR_LEN + headskip);
+ *slack = *align + XDR_QUADLEN(ec + GSS_KRB5_TOK_HDR_LEN + tailskip);
return GSS_S_COMPLETE;
}
@@ -617,9 +626,11 @@ gss_unwrap_kerberos(struct gss_ctx *gctx, int offset,
case ENCTYPE_DES_CBC_RAW:
case ENCTYPE_DES3_CBC_RAW:
case ENCTYPE_ARCFOUR_HMAC:
- return gss_unwrap_kerberos_v1(kctx, offset, len, buf);
+ return gss_unwrap_kerberos_v1(kctx, offset, len, buf,
+ &gctx->slack, &gctx->align);
case ENCTYPE_AES128_CTS_HMAC_SHA1_96:
case ENCTYPE_AES256_CTS_HMAC_SHA1_96:
- return gss_unwrap_kerberos_v2(kctx, offset, len, buf);
+ return gss_unwrap_kerberos_v2(kctx, offset, len, buf,
+ &gctx->slack, &gctx->align);
}
}
> On Apr 19, 2020, at 10:17 PM, Chuck Lever <[email protected]> wrote:
>
> For review:
>
> The purpose of this series is to get the Linux NFS server's
> duplicate reply cache working again when the server is mounted via
> krb5p. Thus I would like to send these three commits via an
> nfsd-5.7-rc pull request in a couple of weeks, depending on review
> comments.
>
> The second patch is strictly a client-side fix, but it is necessary
> because the third patch causes problems on the client unless the
> first and second patches are applied first. Being a client-side
> change, the second patch needs an Acked-by from Trond or Anna so I
> can send a PR via the NFSD tree.
Wondering if I can get appropriate Reviewed-by and Acked-by for
these patches?
> I've tested this series by running "make -j12 test" in a freshly-
> built git source tree on an NFS mount. The test was run on a
> sequence of mounts using every combination of:
>
> - TCP and RDMA
> - NFSv3, NFSv4.0, NFSv4.1, and NFSv4.1
> - krb5p with a kerberos_v1 and kerberos_v2 encryption type
>
> For RDMA in particular, frequent GSS sequence number window overruns
> make the transport connection unstable -- typically over 3,000
> disconnects for a test run that takes about 30 minutes. A
> successful test run on an NFSv3 or NFSv4.0 mount point is therefore
> enough to demonstrate that the server's DRC is working properly.
>
> NFSv4.1+ is also tested to show that krb5p continues to work
> correctly for NFS minor versions that do not happen to use the
> server's DRC.
>
> ---
>
> Chuck Lever (3):
> SUNRPC: Add "@len" parameter to gss_unwrap()
> SUNRPC: Fix GSS privacy computation of auth->au_ralign
> SUNRPC: Revert 241b1f419f0e ("SUNRPC: Remove xdr_buf_trim()")
>
>
> include/linux/sunrpc/gss_api.h | 1 +
> include/linux/sunrpc/xdr.h | 1 +
> net/sunrpc/auth_gss/auth_gss.c | 8 +++-----
> net/sunrpc/auth_gss/gss_krb5_wrap.c | 26 +++++++++++++++--------
> net/sunrpc/auth_gss/svcauth_gss.c | 2 +-
> net/sunrpc/xdr.c | 41 +++++++++++++++++++++++++++++++++++++
> 6 files changed, 65 insertions(+), 14 deletions(-)
>
> --
> Chuck Lever
--
Chuck Lever