[PATCH 19/22] Use confounder length in wrap code

steved
2010-03-15T13:25:57Z

All encryption types use a confounder at the beginning of the
wrap token. In all encryption types except arcfour-hmac, the
confounder is the same as the blocksize. arcfour-hmac has a
blocksize of one, but uses an eight byte confounder.

Add an entry to the crypto framework definitions for the
confounder length and change the wrap/unwrap code to use
the confounder length rather than assuming it is always
the blocksize.

Signed-off-by: Kevin Coffman <kwc@citi.umich.edu>
Signed-off-by: Steve Dickson <steved@redhat.com>
---
include/linux/sunrpc/gss_krb5.h | 3 +++
net/sunrpc/auth_gss/gss_krb5_crypto.c | 6 +++---
net/sunrpc/auth_gss/gss_krb5_mech.c | 4 ++++
net/sunrpc/auth_gss/gss_krb5_wrap.c | 12 +++++++-----
4 files changed, 17 insertions(+), 8 deletions(-)

diff --git a/include/linux/sunrpc/gss_krb5.h b/include/linux/sunrpc/gss_krb5.h
index de87e20..d9f3834 100644
--- a/include/linux/sunrpc/gss_krb5.h
+++ b/include/linux/sunrpc/gss_krb5.h
@@ -64,6 +64,9 @@ struct gss_krb5_enctype {
const u16 signalg; /* signing algorithm */
const u16 sealalg; /* sealing algorithm */
const u32 blocksize; /* encryption blocksize */
+ const u32 conflen; /* confounder length
+ (normally the same as
+ the blocksize) */
const u32 cksumlength; /* checksum length */
const u32 keyed_cksum; /* is it a keyed cksum? */
const u32 keybytes; /* raw key len, in bytes */
diff --git a/net/sunrpc/auth_gss/gss_krb5_crypto.c b/net/sunrpc/auth_gss/gss_krb5_crypto.c
index deb3530..6482185 100644
--- a/net/sunrpc/auth_gss/gss_krb5_crypto.c
+++ b/net/sunrpc/auth_gss/gss_krb5_crypto.c
@@ -573,9 +573,9 @@ gss_krb5_aes_encrypt(struct krb5_ctx *kctx, u32 offset,

/* hide the gss token header and insert the confounder */
offset += GSS_KRB5_TOK_HDR_LEN;
- if (shift_head_data(buf, offset, blocksize))
+ if (shift_head_data(buf, offset, kctx->gk5e->conflen))
return GSS_S_FAILURE;
- make_confounder(buf->head[0].iov_base + offset, blocksize);
+ make_confounder(buf->head[0].iov_base + offset, kctx->gk5e->conflen);
offset -= GSS_KRB5_TOK_HDR_LEN;

if (buf->tail[0].iov_base != NULL) {
@@ -745,7 +745,7 @@ gss_krb5_aes_decrypt(struct krb5_ctx *kctx, u32 offset, struct xdr_buf *buf,
ret = GSS_S_BAD_SIG;
goto out_err;
}
- *headskip = crypto_blkcipher_blocksize(cipher);
+ *headskip = kctx->gk5e->conflen;
*tailskip = kctx->gk5e->cksumlength;
out_err:
if (ret && ret != GSS_S_BAD_SIG)
diff --git a/net/sunrpc/auth_gss/gss_krb5_mech.c b/net/sunrpc/auth_gss/gss_krb5_mech.c
index 4423227..8609934 100644
--- a/net/sunrpc/auth_gss/gss_krb5_mech.c
+++ b/net/sunrpc/auth_gss/gss_krb5_mech.c
@@ -68,6 +68,7 @@ static struct gss_krb5_enctype supported_gss_krb5_enctypes[] = {
.keybytes = 7,
.keylength = 8,
.blocksize = 8,
+ .conflen = 8,
.cksumlength = 8,
.keyed_cksum = 0,
},
@@ -88,6 +89,7 @@ static struct gss_krb5_enctype supported_gss_krb5_enctypes[] = {
.keybytes = 21,
.keylength = 24,
.blocksize = 8,
+ .conflen = 8,
.cksumlength = 20,
.keyed_cksum = 1,
},
@@ -110,6 +112,7 @@ static struct gss_krb5_enctype supported_gss_krb5_enctypes[] = {
.keybytes = 16,
.keylength = 16,
.blocksize = 16,
+ .conflen = 16,
.cksumlength = 12,
.keyed_cksum = 1,
},
@@ -132,6 +135,7 @@ static struct gss_krb5_enctype supported_gss_krb5_enctypes[] = {
.keybytes = 32,
.keylength = 32,
.blocksize = 16,
+ .conflen = 16,
.cksumlength = 12,
.keyed_cksum = 1,
},
diff --git a/net/sunrpc/auth_gss/gss_krb5_wrap.c b/net/sunrpc/auth_gss/gss_krb5_wrap.c
index 2a0d72f..8269f37 100644
--- a/net/sunrpc/auth_gss/gss_krb5_wrap.c
+++ b/net/sunrpc/auth_gss/gss_krb5_wrap.c
@@ -169,6 +169,7 @@ gss_wrap_kerberos_v1(struct krb5_ctx *kctx, int offset,
struct page **tmp_pages;
u32 seq_send;
u8 *cksumkey;
+ u32 conflen = kctx->gk5e->conflen;

dprintk("RPC: %s\n", __func__);

@@ -178,7 +179,7 @@ gss_wrap_kerberos_v1(struct krb5_ctx *kctx, int offset,
blocksize = crypto_blkcipher_blocksize(kctx->enc);
gss_krb5_add_padding(buf, offset, blocksize);
BUG_ON((buf->len - offset) % blocksize);
- plainlen = blocksize + buf->len - offset;
+ plainlen = conflen + buf->len - offset;

headlen = g_token_size(&kctx->mech_used,
GSS_KRB5_TOK_HDR_LEN + kctx->gk5e->cksumlength + plainlen) -
@@ -206,7 +207,7 @@ gss_wrap_kerberos_v1(struct krb5_ctx *kctx, int offset,
memset(ptr + 4, 0xff, 4);
*(__be16 *)(ptr + 4) = cpu_to_le16(kctx->gk5e->sealalg);

- make_confounder(msg_start, blocksize);
+ make_confounder(msg_start, conflen);

if (kctx->gk5e->keyed_cksum)
cksumkey = kctx->cksum;
@@ -216,7 +217,7 @@ gss_wrap_kerberos_v1(struct krb5_ctx *kctx, int offset,
/* XXXJBF: UGH!: */
tmp_pages = buf->pages;
buf->pages = pages;
- if (make_checksum(kctx, ptr, 8, buf, offset + headlen - blocksize,
+ if (make_checksum(kctx, ptr, 8, buf, offset + headlen - conflen,
cksumkey, KG_USAGE_SEAL, &md5cksum))
return GSS_S_FAILURE;
buf->pages = tmp_pages;
@@ -233,7 +234,7 @@ gss_wrap_kerberos_v1(struct krb5_ctx *kctx, int offset,
seq_send, ptr + GSS_KRB5_TOK_HDR_LEN, ptr + 8)))
return GSS_S_FAILURE;

- if (gss_encrypt_xdr_buf(kctx->enc, buf, offset + headlen - blocksize,
+ if (gss_encrypt_xdr_buf(kctx->enc, buf, offset + headlen - conflen,
pages))
return GSS_S_FAILURE;

@@ -256,6 +257,7 @@ gss_unwrap_kerberos_v1(struct krb5_ctx *kctx, int offset, struct xdr_buf *buf)
void *data_start, *orig_start;
int data_len;
int blocksize;
+ u32 conflen = kctx->gk5e->conflen;
int crypt_offset;
u8 *cksumkey;

@@ -329,7 +331,7 @@ gss_unwrap_kerberos_v1(struct krb5_ctx *kctx, int offset, struct xdr_buf *buf)

blocksize = crypto_blkcipher_blocksize(kctx->enc);
data_start = ptr + (GSS_KRB5_TOK_HDR_LEN + kctx->gk5e->cksumlength) +
- blocksize;
+ conflen;
orig_start = buf->head[0].iov_base + offset;
data_len = (buf->head[0].iov_base + buf->head[0].iov_len) - data_start;
memmove(orig_start, data_start, data_len);
--
1.6.6.1