[DCCP]: Registration routines for changing feature values
Two registration routines, for SP and NN features, are provided by this patch,
replacing a previous routine which was used for both feature types.
Signed-off-by: Gerrit Renker <gerrit@xxxxxxxxxxxxxx>
---
net/dccp/feat.c | 120 ++++++++++++++++++++++++++++++++++++++++++++-----------
net/dccp/feat.h | 2
net/dccp/proto.c | 2
3 files changed, 99 insertions(+), 25 deletions(-)
--- a/net/dccp/feat.c
+++ b/net/dccp/feat.c
@@ -294,6 +294,92 @@ cloning_failed:
return -ENOMEM;
}
+static u8 dccp_feat_is_valid_nn_val(u8 feat_num, u64 val)
+{
+ switch (feat_num) {
+ /* Ack Ratio takes 2-byte integer values (11.3) */
+ case DCCPF_ACK_RATIO: return (val <= 0xFFFF);
+ /* Must be between Wmin=32 and Wmax=2^46-1 (7.5.2) */
+ case DCCPF_SEQUENCE_WINDOW: return (val >= 32 &&
+ val <= 0x3FFFFFFFFFFFull);
+ }
+ return 0; /* feature unknown - so we can't tell */
+}
+
+/* check that SP values are within the ranges defined in RFC 4340 */
+static u8 dccp_feat_is_valid_sp_val(u8 feat_num, u8 val)
+{
+ switch (feat_num) {
+ case DCCPF_CCID: return val == 2 || val == 3;
+ case DCCPF_SHORT_SEQNOS: /* fall through */
+ case DCCPF_ECN_INCAPABLE: /* fall through */
+ case DCCPF_SEND_ACK_VECTOR: /* fall through */
+ case DCCPF_SEND_NDP_COUNT: /* fall through */
+ case DCCPF_DATA_CHECKSUM: /* fall through */
+ case DCCPF_SEND_LEV_RATE: return val < 2;
+ case DCCPF_MIN_CSUM_COVER: return val < 16;
+ }
+ return 0; /* feature unknown */
+}
+
+static u8 dccp_feat_sp_list_ok(u8 feat_num, u8 const *sp_list, u8 sp_len)
+{
+ if (sp_list == NULL || sp_len < 1)
+ return 0;
+ while (sp_len--)
+ if (!dccp_feat_is_valid_sp_val(feat_num, *sp_list++))
+ return 0;
+ return 1;
+}
+
+/**
+ * dccp_feat_register_nn - Register new NN value on socket
+ * @fn: feature-negotiation list to register with
+ * @feat: an NN feature from %dccp_feature_numbers
+ * @mandatory: use Mandatory option if 1
+ * @nn_val: value to register (restricted to 4 bytes)
+ * Note that NN features are local by definition (RFC 4340, 6.3.2).
+ */
+static int dccp_feat_register_nn(struct list_head *fn, u8 feat,
+ u8 mandatory, u64 nn_val)
+{
+ dccp_feat_val fval = { .nn = nn_val };
+
+ if (dccp_feat_type(feat) != FEAT_NN ||
+ !dccp_feat_is_valid_nn_val(feat, nn_val))
+ return -EINVAL;
+
+ /* Don't bother with default values, they will be activated anyway. */
+ if (nn_val - (u64)dccp_feat_default_value(feat) == 0)
+ return 0;
+
+ return dccp_feat_push_change(fn, feat, 1, mandatory, &fval);
+}
+
+/**
+ * dccp_feat_register_sp - Register new SP value/list on socket
+ * @fn: feature-negotiation list to register with
+ * @feat: an SP feature from %dccp_feature_numbers
+ * @is_local: whether the local (1) or the remote (0) @feat is meant
+ * @mandatory: use Mandatory option if 1
+ * @sp_val: SP value followed by optional preference list
+ * @sp_len: length of @sp_val in bytes
+ */
+static int dccp_feat_register_sp(struct list_head *fn, u8 feat, u8 is_local,
+ u8 mandatory, u8 const *sp_val, u8 sp_len)
+{
+ dccp_feat_val fval;
+
+ if (dccp_feat_type(feat) != FEAT_SP ||
+ !dccp_feat_sp_list_ok(feat, sp_val, sp_len))
+ return -EINVAL;
+
+ if (dccp_feat_clone_sp_val(&fval, sp_val, sp_len))
+ return -ENOMEM;
+
+ return dccp_feat_push_change(fn, feat, is_local, mandatory, &fval);
+}
+
int dccp_feat_change(struct dccp_minisock *dmsk, u8 type, u8 feature,
u8 *val, u8 len, gfp_t gfp)
{
@@ -830,42 +916,30 @@ out_clean:
EXPORT_SYMBOL_GPL(dccp_feat_clone);
-static int __dccp_feat_init(struct dccp_minisock *dmsk, u8 type, u8 feat,
- u8 *val, u8 len)
-{
- int rc = -ENOMEM;
- u8 *copy = kmemdup(val, len, GFP_KERNEL);
-
- if (copy != NULL) {
- rc = dccp_feat_change(dmsk, type, feat, copy, len, GFP_KERNEL);
- if (rc)
- kfree(copy);
- }
- return rc;
-}
-
-int dccp_feat_init(struct dccp_minisock *dmsk)
+int dccp_feat_init(struct sock *sk)
{
+ struct dccp_sock *dp = dccp_sk(sk);
+ struct dccp_minisock *dmsk = dccp_msk(sk);
int rc;
- INIT_LIST_HEAD(&dmsk->dccpms_pending);
- INIT_LIST_HEAD(&dmsk->dccpms_conf);
+ INIT_LIST_HEAD(&dmsk->dccpms_pending); /* XXX no longer used */
+ INIT_LIST_HEAD(&dmsk->dccpms_conf); /* XXX no longer used */
/* CCID L */
- rc = __dccp_feat_init(dmsk, DCCPO_CHANGE_L, DCCPF_CCID,
- &dmsk->dccpms_tx_ccid, 1);
+ rc = dccp_feat_register_sp(&dp->dccps_featneg, DCCPF_CCID, 1, 0,
+ &dmsk->dccpms_tx_ccid, 1);
if (rc)
goto out;
/* CCID R */
- rc = __dccp_feat_init(dmsk, DCCPO_CHANGE_R, DCCPF_CCID,
- &dmsk->dccpms_rx_ccid, 1);
+ rc = dccp_feat_register_sp(&dp->dccps_featneg, DCCPF_CCID, 0, 0,
+ &dmsk->dccpms_rx_ccid, 1);
if (rc)
goto out;
/* Ack ratio */
- rc = __dccp_feat_init(dmsk, DCCPO_CHANGE_L, DCCPF_ACK_RATIO,
- &dmsk->dccpms_ack_ratio, 1);
+ rc = dccp_feat_register_nn(&dp->dccps_featneg, DCCPF_ACK_RATIO, 0,
+ dmsk->dccpms_ack_ratio);
out:
return rc;
}
--- a/net/dccp/feat.h
+++ b/net/dccp/feat.h
@@ -96,6 +96,6 @@ extern int dccp_feat_confirm_recv(struc
extern void dccp_feat_clean(struct dccp_minisock *dmsk);
extern int dccp_feat_clone(struct sock *oldsk, struct sock *newsk);
extern int dccp_feat_clone_list(struct list_head const *, struct list_head *);
-extern int dccp_feat_init(struct dccp_minisock *dmsk);
+extern int dccp_feat_init(struct sock *sk);
#endif /* _DCCP_FEAT_H */
--- a/net/dccp/proto.c
+++ b/net/dccp/proto.c
@@ -186,7 +186,7 @@ int dccp_init_sock(struct sock *sk, cons
* setsockopt(CCIDs-I-want/accept). -acme
*/
if (likely(ctl_sock_initialized)) {
- int rc = dccp_feat_init(dmsk);
+ int rc = dccp_feat_init(sk);
if (rc)
return rc;
-
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