[DCCP]: Initial feature negotiation implementation
Still needs more work, but boots and doesn't crashes, even
does some negotiation!
18:38:52.174934 127.0.0.1.43458 > 127.0.0.1.5001: request <change_l ack_ratio 2, change_r ccid 2, change_l ccid 2>
18:38:52.218526 127.0.0.1.5001 > 127.0.0.1.43458: response <nop, nop, change_l ack_ratio 2, confirm_r ccid 2 2, confirm_l ccid 2 2, confirm_r ack_ratio 2>
18:38:52.185398 127.0.0.1.43458 > 127.0.0.1.5001: <nop, confirm_r ack_ratio 2, ack_vector0 0x00, elapsed_time 212>
:-)
Signed-off-by: Andrea Bittau <a.bittau@cs.ucl.ac.uk>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/dccp.h b/include/linux/dccp.h
index 268b457..f91c8a6 100644
--- a/include/linux/dccp.h
+++ b/include/linux/dccp.h
@@ -154,6 +154,10 @@
DCCPO_MANDATORY = 1,
DCCPO_MIN_RESERVED = 3,
DCCPO_MAX_RESERVED = 31,
+ DCCPO_CHANGE_L = 32,
+ DCCPO_CONFIRM_L = 33,
+ DCCPO_CHANGE_R = 34,
+ DCCPO_CONFIRM_R = 35,
DCCPO_NDP_COUNT = 37,
DCCPO_ACK_VECTOR_0 = 38,
DCCPO_ACK_VECTOR_1 = 39,
@@ -168,7 +172,9 @@
/* DCCP features */
enum {
DCCPF_RESERVED = 0,
+ DCCPF_CCID = 1,
DCCPF_SEQUENCE_WINDOW = 3,
+ DCCPF_ACK_RATIO = 5,
DCCPF_SEND_ACK_VECTOR = 6,
DCCPF_SEND_NDP_COUNT = 7,
/* 10-127 reserved */
@@ -176,9 +182,18 @@
DCCPF_MAX_CCID_SPECIFIC = 255,
};
+/* this structure is argument to DCCP_SOCKOPT_CHANGE_X */
+struct dccp_so_feat {
+ __u8 dccpsf_feat;
+ __u8 *dccpsf_val;
+ __u8 dccpsf_len;
+};
+
/* DCCP socket options */
#define DCCP_SOCKOPT_PACKET_SIZE 1
#define DCCP_SOCKOPT_SERVICE 2
+#define DCCP_SOCKOPT_CHANGE_L 3
+#define DCCP_SOCKOPT_CHANGE_R 4
#define DCCP_SOCKOPT_CCID_RX_INFO 128
#define DCCP_SOCKOPT_CCID_TX_INFO 192
@@ -314,8 +329,8 @@
/* initial values for each feature */
#define DCCPF_INITIAL_SEQUENCE_WINDOW 100
-/* FIXME: for now we're using CCID 2 (TCP-Like) */
#define DCCPF_INITIAL_CCID 2
+#define DCCPF_INITIAL_ACK_RATIO 2
#define DCCPF_INITIAL_SEND_ACK_VECTOR 1
/* FIXME: for now we're default to 1 but it should really be 0 */
#define DCCPF_INITIAL_SEND_NDP_COUNT 1
@@ -335,6 +350,24 @@
__u8 dccpo_tx_ccid;
__u8 dccpo_send_ack_vector;
__u8 dccpo_send_ndp_count;
+ __u8 dccpo_ack_ratio;
+ struct list_head dccpo_pending;
+ struct list_head dccpo_conf;
+};
+
+struct dccp_opt_conf {
+ __u8 *dccpoc_val;
+ __u8 dccpoc_len;
+};
+
+struct dccp_opt_pend {
+ struct list_head dccpop_node;
+ __u8 dccpop_type;
+ __u8 dccpop_feat;
+ __u8 *dccpop_val;
+ __u8 dccpop_len;
+ int dccpop_conf;
+ struct dccp_opt_conf *dccpop_sc;
};
extern void __dccp_options_init(struct dccp_options *dccpo);
diff --git a/net/dccp/Makefile b/net/dccp/Makefile
index 87b27ff..5736ace 100644
--- a/net/dccp/Makefile
+++ b/net/dccp/Makefile
@@ -4,7 +4,7 @@
obj-$(CONFIG_IP_DCCP) += dccp.o
-dccp-y := ccid.o input.o ipv4.o minisocks.o options.o output.o proto.o \
+dccp-y := ccid.o feat.o input.o ipv4.o minisocks.o options.o output.o proto.o \
timer.o
dccp-$(CONFIG_IP_DCCP_ACKVEC) += ackvec.o
diff --git a/net/dccp/feat.c b/net/dccp/feat.c
new file mode 100644
index 0000000..99d7b7f
--- /dev/null
+++ b/net/dccp/feat.c
@@ -0,0 +1,554 @@
+/*
+ * net/dccp/feat.c
+ *
+ * An implementation of the DCCP protocol
+ * Andrea Bittau <a.bittau@cs.ucl.ac.uk>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+
+#include "dccp.h"
+#include "feat.h"
+
+#define DCCP_FEAT_SP_NOAGREE (-123)
+
+int dccp_feat_change(struct sock *sk, u8 type, u8 feature, u8 *val, u8 len,
+ gfp_t gfp)
+{
+ struct dccp_sock *dp = dccp_sk(sk);
+ struct dccp_opt_pend *opt;
+
+ dccp_pr_debug("feat change type=%d feat=%d\n", type, feature);
+
+ /* check if that feature is already being negotiated */
+ list_for_each_entry(opt, &dp->dccps_options.dccpo_pending,
+ dccpop_node) {
+ /* ok we found a negotiation for this option already */
+ if (opt->dccpop_feat == feature && opt->dccpop_type == type) {
+ dccp_pr_debug("Replacing old\n");
+ /* replace */
+ BUG_ON(opt->dccpop_val == NULL);
+ kfree(opt->dccpop_val);
+ opt->dccpop_val = val;
+ opt->dccpop_len = len;
+ opt->dccpop_conf = 0;
+ return 0;
+ }
+ }
+
+ /* negotiation for a new feature */
+ opt = kmalloc(sizeof(*opt), gfp);
+ if (opt == NULL)
+ return -ENOMEM;
+
+ opt->dccpop_type = type;
+ opt->dccpop_feat = feature;
+ opt->dccpop_len = len;
+ opt->dccpop_val = val;
+ opt->dccpop_conf = 0;
+ opt->dccpop_sc = NULL;
+
+ BUG_ON(opt->dccpop_val == NULL);
+
+ list_add_tail(&opt->dccpop_node, &dp->dccps_options.dccpo_pending);
+ return 0;
+}
+
+EXPORT_SYMBOL_GPL(dccp_feat_change);
+
+/* XXX taking only u8 vals */
+static int dccp_feat_update(struct sock *sk, u8 type, u8 feat, u8 val)
+{
+ /* FIXME implement */
+ dccp_pr_debug("changing [%d] feat %d to %d\n", type, feat, val);
+ return 0;
+}
+
+static int dccp_feat_reconcile(struct sock *sk, struct dccp_opt_pend *opt,
+ u8 *rpref, u8 rlen)
+{
+ struct dccp_sock *dp = dccp_sk(sk);
+ u8 *spref, slen, *res = NULL;
+ int i, j, rc, agree = 1;
+
+ BUG_ON(rpref == NULL);
+
+ /* check if we are the black sheep */
+ if (dp->dccps_role == DCCP_ROLE_CLIENT) {
+ spref = rpref;
+ slen = rlen;
+ rpref = opt->dccpop_val;
+ rlen = opt->dccpop_len;
+ } else {
+ spref = opt->dccpop_val;
+ slen = opt->dccpop_len;
+ }
+ /*
+ * Now we have server preference list in spref and client preference in
+ * rpref
+ */
+ BUG_ON(spref == NULL);
+ BUG_ON(rpref == NULL);
+
+ /* FIXME sanity check vals */
+
+ /* Are values in any order? XXX Lame "algorithm" here */
+ /* XXX assume values are 1 byte */
+ for (i = 0; i < slen; i++) {
+ for (j = 0; j < rlen; j++) {
+ if (spref[i] == rpref[j]) {
+ res = &spref[i];
+ break;
+ }
+ }
+ if (res)
+ break;
+ }
+
+ /* we didn't agree on anything */
+ if (res == NULL) {
+ /* confirm previous value */
+ switch (opt->dccpop_feat) {
+ case DCCPF_CCID:
+ /* XXX did i get this right? =P */
+ if (opt->dccpop_type == DCCPO_CHANGE_L)
+ res = &dp->dccps_options.dccpo_tx_ccid;
+ else
+ res = &dp->dccps_options.dccpo_rx_ccid;
+ break;
+
+ default:
+ WARN_ON(1); /* XXX implement res */
+ return -EFAULT;
+ }
+
+ dccp_pr_debug("Don't agree... reconfirming %d\n", *res);
+ agree = 0; /* this is used for mandatory options... */
+ }
+
+ /* need to put result and our preference list */
+ /* XXX assume 1 byte vals */
+ rlen = 1 + opt->dccpop_len;
+ rpref = kmalloc(rlen, GFP_ATOMIC);
+ if (rpref == NULL)
+ return -ENOMEM;
+
+ *rpref = *res;
+ memcpy(&rpref[1], opt->dccpop_val, opt->dccpop_len);
+
+ /* put it in the "confirm queue" */
+ if (opt->dccpop_sc == NULL) {
+ opt->dccpop_sc = kmalloc(sizeof(*opt->dccpop_sc), GFP_ATOMIC);
+ if (opt->dccpop_sc == NULL) {
+ kfree(rpref);
+ return -ENOMEM;
+ }
+ } else {
+ /* recycle the confirm slot */
+ BUG_ON(opt->dccpop_sc->dccpoc_val == NULL);
+ kfree(opt->dccpop_sc->dccpoc_val);
+ dccp_pr_debug("recycling confirm slot\n");
+ }
+ memset(opt->dccpop_sc, 0, sizeof(*opt->dccpop_sc));
+
+ opt->dccpop_sc->dccpoc_val = rpref;
+ opt->dccpop_sc->dccpoc_len = rlen;
+
+ /* update the option on our side [we are about to send the confirm] */
+ rc = dccp_feat_update(sk, opt->dccpop_type, opt->dccpop_feat, *res);
+ if (rc) {
+ kfree(opt->dccpop_sc->dccpoc_val);
+ kfree(opt->dccpop_sc);
+ opt->dccpop_sc = 0;
+ return rc;
+ }
+
+ dccp_pr_debug("Will confirm %d\n", *rpref);
+
+ /* say we want to change to X but we just got a confirm X, suppress our
+ * change
+ */
+ if (!opt->dccpop_conf) {
+ if (*opt->dccpop_val == *res)
+ opt->dccpop_conf = 1;
+ dccp_pr_debug("won't ask for change of same feature\n");
+ }
+
+ return agree ? 0 : DCCP_FEAT_SP_NOAGREE; /* used for mandatory opts */
+}
+
+static int dccp_feat_sp(struct sock *sk, u8 type, u8 feature, u8 *val, u8 len)
+{
+ struct dccp_sock *dp = dccp_sk(sk);
+ struct dccp_opt_pend *opt;
+ int rc = 1;
+ u8 t;
+
+ /*
+ * We received a CHANGE. We gotta match it against our own preference
+ * list. If we got a CHANGE_R it means it's a change for us, so we need
+ * to compare our CHANGE_L list.
+ */
+ if (type == DCCPO_CHANGE_L)
+ t = DCCPO_CHANGE_R;
+ else
+ t = DCCPO_CHANGE_L;
+
+ /* find our preference list for this feature */
+ list_for_each_entry(opt, &dp->dccps_options.dccpo_pending,
+ dccpop_node) {
+ if (opt->dccpop_type != t || opt->dccpop_feat != feature)
+ continue;
+
+ /* find the winner from the two preference lists */
+ rc = dccp_feat_reconcile(sk, opt, val, len);
+ break;
+ }
+
+ /* We didn't deal with the change. This can happen if we have no
+ * preference list for the feature. In fact, it just shouldn't
+ * happen---if we understand a feature, we should have a preference list
+ * with at least the default value.
+ */
+ BUG_ON(rc == 1);
+
+ return rc;
+}
+
+static int dccp_feat_nn(struct sock *sk, u8 type, u8 feature, u8 *val, u8 len)
+{
+ struct dccp_opt_pend *opt;
+ struct dccp_sock *dp = dccp_sk(sk);
+ u8 *copy;
+ int rc;
+
+ /* NN features must be change L */
+ if (type == DCCPO_CHANGE_R) {
+ dccp_pr_debug("received CHANGE_R %d for NN feat %d\n",
+ type, feature);
+ return -EFAULT;
+ }
+
+ /* XXX sanity check opt val */
+
+ /* copy option so we can confirm it */
+ opt = kzalloc(sizeof(*opt), GFP_ATOMIC);
+ if (opt == NULL)
+ return -ENOMEM;
+
+ copy = kmalloc(len, GFP_ATOMIC);
+ if (copy == NULL) {
+ kfree(opt);
+ return -ENOMEM;
+ }
+ memcpy(copy, val, len);
+
+ opt->dccpop_type = DCCPO_CONFIRM_R; /* NN can only confirm R */
+ opt->dccpop_feat = feature;
+ opt->dccpop_val = copy;
+ opt->dccpop_len = len;
+
+ /* change feature */
+ rc = dccp_feat_update(sk, type, feature, *val);
+ if (rc) {
+ kfree(opt->dccpop_val);
+ kfree(opt);
+ return rc;
+ }
+
+ dccp_pr_debug("Confirming NN feature %d (val=%d)\n", feature, *copy);
+ list_add_tail(&opt->dccpop_node, &dp->dccps_options.dccpo_conf);
+
+ return 0;
+}
+
+static void dccp_feat_empty_confirm(struct sock *sk, u8 type, u8 feature)
+{
+ struct dccp_sock *dp = dccp_sk(sk);
+ /* XXX check if other confirms for that are queued and recycle slot */
+ struct dccp_opt_pend *opt = kzalloc(sizeof(*opt), GFP_ATOMIC);
+
+ if (opt == NULL) {
+ /* XXX what do we do? Ignoring should be fine. It's a change
+ * after all =P
+ */
+ return;
+ }
+
+ opt->dccpop_type = type == DCCPO_CHANGE_L ? DCCPO_CONFIRM_R :
+ DCCPO_CONFIRM_L;
+ opt->dccpop_feat = feature;
+ opt->dccpop_val = 0;
+ opt->dccpop_len = 0;
+
+ /* change feature */
+ dccp_pr_debug("Empty confirm feature %d type %d\n", feature, type);
+ list_add_tail(&opt->dccpop_node, &dp->dccps_options.dccpo_conf);
+}
+
+static void dccp_feat_flush_confirm(struct sock *sk)
+{
+ struct dccp_sock *dp = dccp_sk(sk);
+ /* Check if there is anything to confirm in the first place */
+ int yes = !list_empty(&dp->dccps_options.dccpo_conf);
+
+ if (!yes) {
+ struct dccp_opt_pend *opt;
+
+ list_for_each_entry(opt, &dp->dccps_options.dccpo_pending,
+ dccpop_node) {
+ if (opt->dccpop_conf) {
+ yes = 1;
+ break;
+ }
+ }
+ }
+
+ if (!yes)
+ return;
+
+ /* OK there is something to confirm... */
+ /* XXX check if packet is in flight? Send delayed ack?? */
+ if (sk->sk_state == DCCP_OPEN)
+ dccp_send_ack(sk);
+}
+
+int dccp_feat_change_recv(struct sock *sk, u8 type, u8 feature, u8 *val, u8 len)
+{
+ int rc;
+
+ dccp_pr_debug("got feat change type=%d feat=%d\n", type, feature);
+
+ /* figure out if it's SP or NN feature */
+ switch (feature) {
+ /* deal with SP features */
+ case DCCPF_CCID:
+ rc = dccp_feat_sp(sk, type, feature, val, len);
+ break;
+
+ /* deal with NN features */
+ case DCCPF_ACK_RATIO:
+ rc = dccp_feat_nn(sk, type, feature, val, len);
+ break;
+
+ /* XXX implement other features */
+ default:
+ rc = -EFAULT;
+ break;
+ }
+
+ /* check if there were problems changing features */
+ if (rc) {
+ /* If we don't agree on SP, we sent a confirm for old value.
+ * However we propagate rc to caller in case option was
+ * mandatory
+ */
+ if (rc != DCCP_FEAT_SP_NOAGREE)
+ dccp_feat_empty_confirm(sk, type, feature);
+ }
+
+ /* generate the confirm [if required] */
+ dccp_feat_flush_confirm(sk);
+
+ return rc;
+}
+
+EXPORT_SYMBOL_GPL(dccp_feat_change_recv);
+
+int dccp_feat_confirm_recv(struct sock *sk, u8 type, u8 feature,
+ u8 *val, u8 len)
+{
+ u8 t;
+ struct dccp_opt_pend *opt;
+ struct dccp_sock *dp = dccp_sk(sk);
+ int rc = 1;
+ int all_confirmed = 1;
+
+ dccp_pr_debug("got feat confirm type=%d feat=%d\n", type, feature);
+
+ /* XXX sanity check type & feat */
+
+ /* locate our change request */
+ t = type == DCCPO_CONFIRM_L ? DCCPO_CHANGE_R : DCCPO_CHANGE_L;
+
+ list_for_each_entry(opt, &dp->dccps_options.dccpo_pending,
+ dccpop_node) {
+ if (!opt->dccpop_conf && opt->dccpop_type == t &&
+ opt->dccpop_feat == feature) {
+ /* we found it */
+ /* XXX do sanity check */
+
+ opt->dccpop_conf = 1;
+
+ /* We got a confirmation---change the option */
+ dccp_feat_update(sk, opt->dccpop_type,
+ opt->dccpop_feat, *val);
+
+ dccp_pr_debug("feat %d type %d confirmed %d\n",
+ feature, type, *val);
+ rc = 0;
+ break;
+ }
+
+ if (!opt->dccpop_conf)
+ all_confirmed = 0;
+ }
+
+ /* fix re-transmit timer */
+ /* XXX gotta make sure that no option negotiation occurs during
+ * connection shutdown. Consider that the CLOSEREQ is sent and timer is
+ * on. if all options are confirmed it might kill timer which should
+ * remain alive until close is received.
+ */
+ if (all_confirmed) {
+ dccp_pr_debug("clear feat negotiation timer %p\n", sk);
+ inet_csk_clear_xmit_timer(sk, ICSK_TIME_RETRANS);
+ }
+
+ if (rc)
+ dccp_pr_debug("feat %d type %d never requested\n",
+ feature, type);
+ return 0;
+}
+
+EXPORT_SYMBOL_GPL(dccp_feat_confirm_recv);
+
+void dccp_feat_clean(struct sock *sk)
+{
+ struct dccp_sock *dp = dccp_sk(sk);
+ struct dccp_opt_pend *opt, *next;
+
+ list_for_each_entry_safe(opt, next, &dp->dccps_options.dccpo_pending,
+ dccpop_node) {
+ BUG_ON(opt->dccpop_val == NULL);
+ kfree(opt->dccpop_val);
+
+ if (opt->dccpop_sc != NULL) {
+ BUG_ON(opt->dccpop_sc->dccpoc_val == NULL);
+ kfree(opt->dccpop_sc->dccpoc_val);
+ kfree(opt->dccpop_sc);
+ }
+
+ kfree(opt);
+ }
+ INIT_LIST_HEAD(&dp->dccps_options.dccpo_pending);
+
+ list_for_each_entry_safe(opt, next, &dp->dccps_options.dccpo_conf,
+ dccpop_node) {
+ BUG_ON(opt == NULL);
+ if (opt->dccpop_val != NULL)
+ kfree(opt->dccpop_val);
+ kfree(opt);
+ }
+ INIT_LIST_HEAD(&dp->dccps_options.dccpo_conf);
+}
+
+EXPORT_SYMBOL_GPL(dccp_feat_clean);
+
+/* this is to be called only when a listening sock creates its child. It is
+ * assumed by the function---the confirm is not duplicated, but rather it is
+ * "passed on".
+ */
+int dccp_feat_clone(struct sock *oldsk, struct sock *newsk)
+{
+ struct dccp_sock *olddp = dccp_sk(oldsk);
+ struct dccp_sock *newdp = dccp_sk(newsk);
+ struct dccp_opt_pend *opt;
+ int rc = 0;
+
+ INIT_LIST_HEAD(&newdp->dccps_options.dccpo_pending);
+ INIT_LIST_HEAD(&newdp->dccps_options.dccpo_conf);
+
+ list_for_each_entry(opt, &olddp->dccps_options.dccpo_pending,
+ dccpop_node) {
+ struct dccp_opt_pend *newopt;
+ /* copy the value of the option */
+ u8 *val = kmalloc(opt->dccpop_len, GFP_ATOMIC);
+
+ if (val == NULL)
+ goto out_clean;
+ memcpy(val, opt->dccpop_val, opt->dccpop_len);
+
+ newopt = kmalloc(sizeof(*newopt), GFP_ATOMIC);
+ if (newopt == NULL) {
+ kfree(val);
+ goto out_clean;
+ }
+
+ /* insert the option */
+ memcpy(newopt, opt, sizeof(*newopt));
+ newopt->dccpop_val = val;
+ list_add_tail(&newopt->dccpop_node,
+ &newdp->dccps_options.dccpo_pending);
+
+ /* XXX what happens with backlogs and multiple connections at
+ * once...
+ */
+ /* the master socket no longer needs to worry about confirms */
+ opt->dccpop_sc = 0; /* it's not a memleak---new socket has it */
+
+ /* reset state for a new socket */
+ opt->dccpop_conf = 0;
+ }
+
+ /* XXX not doing anything about the conf queue */
+
+out:
+ return rc;
+
+out_clean:
+ dccp_feat_clean(newsk);
+ rc = -ENOMEM;
+ goto out;
+}
+
+EXPORT_SYMBOL_GPL(dccp_feat_clone);
+
+static int __dccp_feat_init(struct sock *sk, u8 type, u8 feat, u8 *val, u8 len)
+{
+ int rc = -ENOMEM;
+ u8 *copy = kmalloc(len, GFP_KERNEL);
+
+ if (copy != NULL) {
+ memcpy(copy, val, len);
+ rc = dccp_feat_change(sk, type, feat, copy, len, GFP_KERNEL);
+ if (rc)
+ kfree(copy);
+ }
+ return rc;
+}
+
+int dccp_feat_init(struct sock *sk)
+{
+ struct dccp_sock *dp = dccp_sk(sk);
+ int rc;
+
+ INIT_LIST_HEAD(&dp->dccps_options.dccpo_pending);
+ INIT_LIST_HEAD(&dp->dccps_options.dccpo_conf);
+
+ /* CCID L */
+ rc = __dccp_feat_init(sk, DCCPO_CHANGE_L, DCCPF_CCID,
+ &dp->dccps_options.dccpo_tx_ccid, 1);
+ if (rc)
+ goto out;
+
+ /* CCID R */
+ rc = __dccp_feat_init(sk, DCCPO_CHANGE_R, DCCPF_CCID,
+ &dp->dccps_options.dccpo_rx_ccid, 1);
+ if (rc)
+ goto out;
+
+ /* Ack ratio */
+ rc = __dccp_feat_init(sk, DCCPO_CHANGE_L, DCCPF_ACK_RATIO,
+ &dp->dccps_options.dccpo_ack_ratio, 1);
+out:
+ return rc;
+}
+
+EXPORT_SYMBOL_GPL(dccp_feat_init);
diff --git a/net/dccp/feat.h b/net/dccp/feat.h
new file mode 100644
index 0000000..67da062
--- /dev/null
+++ b/net/dccp/feat.h
@@ -0,0 +1,28 @@
+#ifndef _DCCP_FEAT_H
+#define _DCCP_FEAT_H
+/*
+ * net/dccp/feat.h
+ *
+ * An implementation of the DCCP protocol
+ * Copyright (c) 2005 Andrea Bittau <a.bittau@cs.ucl.ac.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/types.h>
+
+struct sock;
+
+extern int dccp_feat_change(struct sock *sk, u8 type, u8 feature,
+ u8 *val, u8 len, gfp_t gfp);
+extern int dccp_feat_change_recv(struct sock *sk, u8 type, u8 feature,
+ u8 *val, u8 len);
+extern int dccp_feat_confirm_recv(struct sock *sk, u8 type, u8 feature,
+ u8 *val, u8 len);
+extern void dccp_feat_clean(struct sock *sk);
+extern int dccp_feat_clone(struct sock *oldsk, struct sock *newsk);
+extern int dccp_feat_init(struct sock *sk);
+
+#endif /* _DCCP_FEAT_H */
diff --git a/net/dccp/input.c b/net/dccp/input.c
index b6cba72..4b6d43d 100644
--- a/net/dccp/input.c
+++ b/net/dccp/input.c
@@ -300,6 +300,9 @@
goto out_invalid_packet;
}
+ if (dccp_parse_options(sk, skb))
+ goto out_invalid_packet;
+
if (dp->dccps_options.dccpo_send_ack_vector &&
dccp_ackvec_add(dp->dccps_hc_rx_ackvec, sk,
DCCP_SKB_CB(skb)->dccpd_seq,
diff --git a/net/dccp/ipv4.c b/net/dccp/ipv4.c
index 38321ad..fcfb486 100644
--- a/net/dccp/ipv4.c
+++ b/net/dccp/ipv4.c
@@ -28,6 +28,7 @@
#include "ackvec.h"
#include "ccid.h"
#include "dccp.h"
+#include "feat.h"
struct inet_hashinfo __cacheline_aligned dccp_hashinfo = {
.lhash_lock = RW_LOCK_UNLOCKED,
@@ -535,7 +536,8 @@
if (req == NULL)
goto drop;
- /* FIXME: process options */
+ if (dccp_parse_options(sk, skb))
+ goto drop;
dccp_openreq_init(req, &dp, skb);
@@ -1049,6 +1051,8 @@
* setsockopt(CCIDs-I-want/accept). -acme
*/
if (likely(!dccp_ctl_socket_init)) {
+ int rc;
+
if (dp->dccps_options.dccpo_send_ack_vector) {
dp->dccps_hc_rx_ackvec = dccp_ackvec_alloc(GFP_KERNEL);
if (dp->dccps_hc_rx_ackvec == NULL)
@@ -1069,8 +1073,16 @@
dp->dccps_hc_rx_ccid = dp->dccps_hc_tx_ccid = NULL;
return -ENOMEM;
}
- } else
+
+ rc = dccp_feat_init(sk);
+ if (rc)
+ return rc;
+ } else {
+ /* control socket doesn't need feat nego */
+ INIT_LIST_HEAD(&dp->dccps_options.dccpo_pending);
+ INIT_LIST_HEAD(&dp->dccps_options.dccpo_conf);
dccp_ctl_socket_init = 0;
+ }
dccp_init_xmit_timers(sk);
icsk->icsk_rto = DCCP_TIMEOUT_INIT;
@@ -1118,6 +1130,9 @@
ccid_exit(dp->dccps_hc_tx_ccid, sk);
dp->dccps_hc_rx_ccid = dp->dccps_hc_tx_ccid = NULL;
+ /* clean up feature negotiation state */
+ dccp_feat_clean(sk);
+
return 0;
}
diff --git a/net/dccp/minisocks.c b/net/dccp/minisocks.c
index a60a3e9..9e1de59 100644
--- a/net/dccp/minisocks.c
+++ b/net/dccp/minisocks.c
@@ -22,6 +22,7 @@
#include "ackvec.h"
#include "ccid.h"
#include "dccp.h"
+#include "feat.h"
struct inet_timewait_death_row dccp_death_row = {
.sysctl_max_tw_buckets = NR_FILE * 2,
@@ -114,6 +115,9 @@
newicsk->icsk_rto = DCCP_TIMEOUT_INIT;
do_gettimeofday(&newdp->dccps_epoch);
+ if (dccp_feat_clone(sk, newsk))
+ goto out_free;
+
if (newdp->dccps_options.dccpo_send_ack_vector) {
newdp->dccps_hc_rx_ackvec =
dccp_ackvec_alloc(GFP_ATOMIC);
diff --git a/net/dccp/options.c b/net/dccp/options.c
index 0a76426..7f99306 100644
--- a/net/dccp/options.c
+++ b/net/dccp/options.c
@@ -21,12 +21,14 @@
#include "ackvec.h"
#include "ccid.h"
#include "dccp.h"
+#include "feat.h"
/* stores the default values for new connection. may be changed with sysctl */
static const struct dccp_options dccpo_default_values = {
.dccpo_sequence_window = DCCPF_INITIAL_SEQUENCE_WINDOW,
.dccpo_rx_ccid = DCCPF_INITIAL_CCID,
.dccpo_tx_ccid = DCCPF_INITIAL_CCID,
+ .dccpo_ack_ratio = DCCPF_INITIAL_ACK_RATIO,
.dccpo_send_ack_vector = DCCPF_INITIAL_SEND_ACK_VECTOR,
.dccpo_send_ndp_count = DCCPF_INITIAL_SEND_NDP_COUNT,
};
@@ -69,6 +71,8 @@
unsigned char opt, len;
unsigned char *value;
u32 elapsed_time;
+ int rc;
+ int mandatory = 0;
memset(opt_recv, 0, sizeof(*opt_recv));
@@ -100,6 +104,11 @@
switch (opt) {
case DCCPO_PADDING:
break;
+ case DCCPO_MANDATORY:
+ if (mandatory)
+ goto out_invalid_option;
+ mandatory = 1;
+ break;
case DCCPO_NDP_COUNT:
if (len > 3)
goto out_invalid_option;
@@ -108,6 +117,31 @@
dccp_pr_debug("%sNDP count=%d\n", debug_prefix,
opt_recv->dccpor_ndp);
break;
+ case DCCPO_CHANGE_L:
+ /* fall through */
+ case DCCPO_CHANGE_R:
+ if (len < 2)
+ goto out_invalid_option;
+ rc = dccp_feat_change_recv(sk, opt, *value, value + 1,
+ len - 1);
+ /*
+ * When there is a change error, change_recv is
+ * responsible for dealing with it. i.e. reply with an
+ * empty confirm.
+ * If the change was mandatory, then we need to die.
+ */
+ if (rc && mandatory)
+ goto out_invalid_option;
+ break;
+ case DCCPO_CONFIRM_L:
+ /* fall through */
+ case DCCPO_CONFIRM_R:
+ if (len < 2)
+ goto out_invalid_option;
+ if (dccp_feat_confirm_recv(sk, opt, *value,
+ value + 1, len - 1))
+ goto out_invalid_option;
+ break;
case DCCPO_ACK_VECTOR_0:
case DCCPO_ACK_VECTOR_1:
if (pkt_type == DCCP_PKT_DATA)
@@ -208,6 +242,9 @@
sk, opt, len);
break;
}
+
+ if (opt != DCCPO_MANDATORY)
+ mandatory = 0;
}
return 0;
@@ -356,7 +393,7 @@
{
struct timeval tv;
u32 now;
-
+
dccp_timestamp(sk, &tv);
now = timeval_usecs(&tv) / 10;
/* yes this will overflow but that is the point as we want a
@@ -402,7 +439,7 @@
tstamp_echo = htonl(dp->dccps_timestamp_echo);
memcpy(to, &tstamp_echo, 4);
to += 4;
-
+
if (elapsed_time_len == 2) {
const u16 var16 = htons((u16)elapsed_time);
memcpy(to, &var16, 2);
@@ -421,6 +458,93 @@
dp->dccps_timestamp_time.tv_usec = 0;
}
+static int dccp_insert_feat_opt(struct sk_buff *skb, u8 type, u8 feat,
+ u8 *val, u8 len)
+{
+ u8 *to;
+
+ if (DCCP_SKB_CB(skb)->dccpd_opt_len + len + 3 > DCCP_MAX_OPT_LEN) {
+ LIMIT_NETDEBUG(KERN_INFO "DCCP: packet too small"
+ " to insert feature %d option!\n", feat);
+ return -1;
+ }
+
+ DCCP_SKB_CB(skb)->dccpd_opt_len += len + 3;
+
+ to = skb_push(skb, len + 3);
+ *to++ = type;
+ *to++ = len + 3;
+ *to++ = feat;
+
+ if (len)
+ memcpy(to, val, len);
+ dccp_pr_debug("option %d feat %d len %d\n", type, feat, len);
+
+ return 0;
+}
+
+static void dccp_insert_feat(struct sock *sk, struct sk_buff *skb)
+{
+ struct dccp_sock *dp = dccp_sk(sk);
+ struct dccp_opt_pend *opt, *next;
+ int change = 0;
+
+ /* confirm any options [NN opts] */
+ list_for_each_entry_safe(opt, next, &dp->dccps_options.dccpo_conf,
+ dccpop_node) {
+ dccp_insert_feat_opt(skb, opt->dccpop_type,
+ opt->dccpop_feat, opt->dccpop_val,
+ opt->dccpop_len);
+ /* fear empty confirms */
+ if (opt->dccpop_val)
+ kfree(opt->dccpop_val);
+ kfree(opt);
+ }
+ INIT_LIST_HEAD(&dp->dccps_options.dccpo_conf);
+
+ /* see which features we need to send */
+ list_for_each_entry(opt, &dp->dccps_options.dccpo_pending,
+ dccpop_node) {
+ /* see if we need to send any confirm */
+ if (opt->dccpop_sc) {
+ dccp_insert_feat_opt(skb, opt->dccpop_type + 1,
+ opt->dccpop_feat,
+ opt->dccpop_sc->dccpoc_val,
+ opt->dccpop_sc->dccpoc_len);
+
+ BUG_ON(!opt->dccpop_sc->dccpoc_val);
+ kfree(opt->dccpop_sc->dccpoc_val);
+ kfree(opt->dccpop_sc);
+ opt->dccpop_sc = NULL;
+ }
+
+ /* any option not confirmed, re-send it */
+ if (!opt->dccpop_conf) {
+ dccp_insert_feat_opt(skb, opt->dccpop_type,
+ opt->dccpop_feat, opt->dccpop_val,
+ opt->dccpop_len);
+ change++;
+ }
+ }
+
+ /* Retransmit timer.
+ * If this is the master listening sock, we don't set a timer on it. It
+ * should be fine because if the dude doesn't receive our RESPONSE
+ * [which will contain the CHANGE] he will send another REQUEST which
+ * will "retrnasmit" the change.
+ */
+ if (change && dp->dccps_role != DCCP_ROLE_LISTEN) {
+ dccp_pr_debug("reset feat negotiation timer %p\n", sk);
+
+ /* XXX don't reset the timer on re-transmissions. I.e. reset it
+ * only when sending new stuff i guess. Currently the timer
+ * never backs off because on re-transmission it just resets it!
+ */
+ inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS,
+ inet_csk(sk)->icsk_rto, DCCP_RTO_MAX);
+ }
+}
+
void dccp_insert_options(struct sock *sk, struct sk_buff *skb)
{
struct dccp_sock *dp = dccp_sk(sk);
@@ -447,6 +571,17 @@
dp->dccps_hc_tx_insert_options = 0;
}
+ /* Feature negotiation */
+ switch(DCCP_SKB_CB(skb)->dccpd_type) {
+ /* Data packets can't do feat negotiation */
+ case DCCP_PKT_DATA:
+ case DCCP_PKT_DATAACK:
+ break;
+ default:
+ dccp_insert_feat(sk, skb);
+ break;
+ }
+
/* XXX: insert other options when appropriate */
if (DCCP_SKB_CB(skb)->dccpd_opt_len != 0) {
diff --git a/net/dccp/output.c b/net/dccp/output.c
index efd7ffb..0cc2bcf 100644
--- a/net/dccp/output.c
+++ b/net/dccp/output.c
@@ -64,6 +64,10 @@
case DCCP_PKT_DATAACK:
break;
+ case DCCP_PKT_REQUEST:
+ set_ack = 0;
+ /* fall through */
+
case DCCP_PKT_SYNC:
case DCCP_PKT_SYNCACK:
ackno = dcb->dccpd_seq;
diff --git a/net/dccp/proto.c b/net/dccp/proto.c
index 81ad249..1a8cf8e 100644
--- a/net/dccp/proto.c
+++ b/net/dccp/proto.c
@@ -37,6 +37,7 @@
#include "ccid.h"
#include "dccp.h"
+#include "feat.h"
DEFINE_SNMP_STAT(struct dccp_mib, dccp_statistics) __read_mostly;
@@ -255,6 +256,39 @@
return 0;
}
+/* byte 1 is feature. the rest is the preference list */
+static int dccp_setsockopt_change(struct sock *sk, int type,
+ struct dccp_so_feat __user *optval)
+{
+ struct dccp_so_feat opt;
+ u8 *val;
+ int rc;
+
+ if (copy_from_user(&opt, optval, sizeof(opt)))
+ return -EFAULT;
+
+ val = kmalloc(opt.dccpsf_len, GFP_KERNEL);
+ if (!val)
+ return -ENOMEM;
+
+ if (copy_from_user(val, opt.dccpsf_val, opt.dccpsf_len)) {
+ rc = -EFAULT;
+ goto out_free_val;
+ }
+
+ rc = dccp_feat_change(sk, type, opt.dccpsf_feat, val, opt.dccpsf_len,
+ GFP_KERNEL);
+ if (rc)
+ goto out_free_val;
+
+out:
+ return rc;
+
+out_free_val:
+ kfree(val);
+ goto out;
+}
+
int dccp_setsockopt(struct sock *sk, int level, int optname,
char __user *optval, int optlen)
{
@@ -284,6 +318,25 @@
case DCCP_SOCKOPT_PACKET_SIZE:
dp->dccps_packet_size = val;
break;
+
+ case DCCP_SOCKOPT_CHANGE_L:
+ if (optlen != sizeof(struct dccp_so_feat))
+ err = -EINVAL;
+ else
+ err = dccp_setsockopt_change(sk, DCCPO_CHANGE_L,
+ (struct dccp_so_feat *)
+ optval);
+ break;
+
+ case DCCP_SOCKOPT_CHANGE_R:
+ if (optlen != sizeof(struct dccp_so_feat))
+ err = -EINVAL;
+ else
+ err = dccp_setsockopt_change(sk, DCCPO_CHANGE_R,
+ (struct dccp_so_feat *)
+ optval);
+ break;
+
default:
err = -ENOPROTOOPT;
break;
diff --git a/net/dccp/timer.c b/net/dccp/timer.c
index aa34b57..d7c7866 100644
--- a/net/dccp/timer.c
+++ b/net/dccp/timer.c
@@ -141,6 +141,17 @@
{
struct inet_connection_sock *icsk = inet_csk(sk);
+ /* retransmit timer is used for feature negotiation throughout
+ * connection. In this case, no packet is re-transmitted, but rather an
+ * ack is generated and pending changes are splaced into its options.
+ */
+ if (sk->sk_send_head == NULL) {
+ dccp_pr_debug("feat negotiation retransmit timeout %p\n", sk);
+ if (sk->sk_state == DCCP_OPEN)
+ dccp_send_ack(sk);
+ goto backoff;
+ }
+
/*
* sk->sk_send_head has to have one skb with
* DCCP_SKB_CB(skb)->dccpd_type set to one of the retransmittable DCCP
@@ -177,6 +188,7 @@
goto out;
}
+backoff:
icsk->icsk_backoff++;
icsk->icsk_retransmits++;