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-rw-r--r--Documentation/networking/strparser.txt136
-rw-r--r--include/net/kcm.h37
-rw-r--r--include/net/strparser.h145
-rw-r--r--net/Kconfig1
-rw-r--r--net/Makefile1
-rw-r--r--net/ipv6/ila/ila_common.c1
-rw-r--r--net/kcm/Kconfig1
-rw-r--r--net/kcm/kcmproc.c44
-rw-r--r--net/kcm/kcmsock.c456
-rw-r--r--net/strparser/Kconfig4
-rw-r--r--net/strparser/Makefile1
-rw-r--r--net/strparser/strparser.c492
12 files changed, 896 insertions, 423 deletions
diff --git a/Documentation/networking/strparser.txt b/Documentation/networking/strparser.txt
new file mode 100644
index 000000000000..a0bf573dfa61
--- /dev/null
+++ b/Documentation/networking/strparser.txt
@@ -0,0 +1,136 @@
+Stream Parser
+-------------
+
+The stream parser (strparser) is a utility that parses messages of an
+application layer protocol running over a TCP connection. The stream
+parser works in conjunction with an upper layer in the kernel to provide
+kernel support for application layer messages. For instance, Kernel
+Connection Multiplexor (KCM) uses the Stream Parser to parse messages
+using a BPF program.
+
+Interface
+---------
+
+The API includes a context structure, a set of callbacks, utility
+functions, and a data_ready function. The callbacks include
+a parse_msg function that is called to perform parsing (e.g.
+BPF parsing in case of KCM), and a rcv_msg function that is called
+when a full message has been completed.
+
+A stream parser can be instantiated for a TCP connection. This is done
+by:
+
+strp_init(struct strparser *strp, struct sock *csk,
+ struct strp_callbacks *cb)
+
+strp is a struct of type strparser that is allocated by the upper layer.
+csk is the TCP socket associated with the stream parser. Callbacks are
+called by the stream parser.
+
+Callbacks
+---------
+
+There are four callbacks:
+
+int (*parse_msg)(struct strparser *strp, struct sk_buff *skb);
+
+ parse_msg is called to determine the length of the next message
+ in the stream. The upper layer must implement this function. It
+ should parse the sk_buff as containing the headers for the
+ next application layer messages in the stream.
+
+ The skb->cb in the input skb is a struct strp_rx_msg. Only
+ the offset field is relevant in parse_msg and gives the offset
+ where the message starts in the skb.
+
+ The return values of this function are:
+
+ >0 : indicates length of successfully parsed message
+ 0 : indicates more data must be received to parse the message
+ -ESTRPIPE : current message should not be processed by the
+ kernel, return control of the socket to userspace which
+ can proceed to read the messages itself
+ other < 0 : Error is parsing, give control back to userspace
+ assuming that synchronization is lost and the stream
+ is unrecoverable (application expected to close TCP socket)
+
+ In the case that an error is returned (return value is less than
+ zero) the stream parser will set the error on TCP socket and wake
+ it up. If parse_msg returned -ESTRPIPE and the stream parser had
+ previously read some bytes for the current message, then the error
+ set on the attached socket is ENODATA since the stream is
+ unrecoverable in that case.
+
+void (*rcv_msg)(struct strparser *strp, struct sk_buff *skb);
+
+ rcv_msg is called when a full message has been received and
+ is queued. The callee must consume the sk_buff; it can
+ call strp_pause to prevent any further messages from being
+ received in rcv_msg (see strp_pause below). This callback
+ must be set.
+
+ The skb->cb in the input skb is a struct strp_rx_msg. This
+ struct contains two fields: offset and full_len. Offset is
+ where the message starts in the skb, and full_len is the
+ the length of the message. skb->len - offset may be greater
+ then full_len since strparser does not trim the skb.
+
+int (*read_sock_done)(struct strparser *strp, int err);
+
+ read_sock_done is called when the stream parser is done reading
+ the TCP socket. The stream parser may read multiple messages
+ in a loop and this function allows cleanup to occur when existing
+ the loop. If the callback is not set (NULL in strp_init) a
+ default function is used.
+
+void (*abort_parser)(struct strparser *strp, int err);
+
+ This function is called when stream parser encounters an error
+ in parsing. The default function stops the stream parser for the
+ TCP socket and sets the error in the socket. The default function
+ can be changed by setting the callback to non-NULL in strp_init.
+
+Functions
+---------
+
+The upper layer calls strp_tcp_data_ready when data is ready on the lower
+socket for strparser to process. This should be called from a data_ready
+callback that is set on the socket.
+
+strp_stop is called to completely stop stream parser operations. This
+is called internally when the stream parser encounters an error, and
+it is called from the upper layer when unattaching a TCP socket.
+
+strp_done is called to unattach the stream parser from the TCP socket.
+This must be called after the stream processor has be stopped.
+
+strp_check_rcv is called to check for new messages on the socket. This
+is normally called at initialization of the a stream parser instance
+of after strp_unpause.
+
+Statistics
+----------
+
+Various counters are kept for each stream parser for a TCP socket.
+These are in the strp_stats structure. strp_aggr_stats is a convenience
+structure for accumulating statistics for multiple stream parser
+instances. save_strp_stats and aggregate_strp_stats are helper functions
+to save and aggregate statistics.
+
+Message assembly limits
+-----------------------
+
+The stream parser provide mechanisms to limit the resources consumed by
+message assembly.
+
+A timer is set when assembly starts for a new message. The message
+timeout is taken from rcvtime for the associated TCP socket. If the
+timer fires before assembly completes the stream parser is aborted
+and the ETIMEDOUT error is set on the TCP socket.
+
+Message length is limited to the receive buffer size of the associated
+TCP socket. If the length returned by parse_msg is greater than
+the socket buffer size then the stream parser is aborted with
+EMSGSIZE error set on the TCP socket. Note that this makes the
+maximum size of receive skbuffs for a socket with a stream parser
+to be 2*sk_rcvbuf of the TCP socket.
diff --git a/include/net/kcm.h b/include/net/kcm.h
index 2840b5825dcc..2a8965819db0 100644
--- a/include/net/kcm.h
+++ b/include/net/kcm.h
@@ -13,6 +13,7 @@
#include <linux/skbuff.h>
#include <net/sock.h>
+#include <net/strparser.h>
#include <uapi/linux/kcm.h>
extern unsigned int kcm_net_id;
@@ -21,16 +22,8 @@ extern unsigned int kcm_net_id;
#define KCM_STATS_INCR(stat) ((stat)++)
struct kcm_psock_stats {
- unsigned long long rx_msgs;
- unsigned long long rx_bytes;
unsigned long long tx_msgs;
unsigned long long tx_bytes;
- unsigned int rx_aborts;
- unsigned int rx_mem_fail;
- unsigned int rx_need_more_hdr;
- unsigned int rx_msg_too_big;
- unsigned int rx_msg_timeouts;
- unsigned int rx_bad_hdr_len;
unsigned long long reserved;
unsigned long long unreserved;
unsigned int tx_aborts;
@@ -64,13 +57,6 @@ struct kcm_tx_msg {
struct sk_buff *last_skb;
};
-struct kcm_rx_msg {
- int full_len;
- int accum_len;
- int offset;
- int early_eaten;
-};
-
/* Socket structure for KCM client sockets */
struct kcm_sock {
struct sock sk;
@@ -87,6 +73,7 @@ struct kcm_sock {
struct work_struct tx_work;
struct list_head wait_psock_list;
struct sk_buff *seq_skb;
+ u32 tx_stopped : 1;
/* Don't use bit fields here, these are set under different locks */
bool tx_wait;
@@ -104,11 +91,11 @@ struct bpf_prog;
/* Structure for an attached lower socket */
struct kcm_psock {
struct sock *sk;
+ struct strparser strp;
struct kcm_mux *mux;
int index;
u32 tx_stopped : 1;
- u32 rx_stopped : 1;
u32 done : 1;
u32 unattaching : 1;
@@ -121,18 +108,12 @@ struct kcm_psock {
struct kcm_psock_stats stats;
/* Receive */
- struct sk_buff *rx_skb_head;
- struct sk_buff **rx_skb_nextp;
- struct sk_buff *ready_rx_msg;
struct list_head psock_ready_list;
- struct work_struct rx_work;
- struct delayed_work rx_delayed_work;
struct bpf_prog *bpf_prog;
struct kcm_sock *rx_kcm;
unsigned long long saved_rx_bytes;
unsigned long long saved_rx_msgs;
- struct timer_list rx_msg_timer;
- unsigned int rx_need_bytes;
+ struct sk_buff *ready_rx_msg;
/* Transmit */
struct kcm_sock *tx_kcm;
@@ -146,6 +127,7 @@ struct kcm_net {
struct mutex mutex;
struct kcm_psock_stats aggregate_psock_stats;
struct kcm_mux_stats aggregate_mux_stats;
+ struct strp_aggr_stats aggregate_strp_stats;
struct list_head mux_list;
int count;
};
@@ -163,6 +145,7 @@ struct kcm_mux {
struct kcm_mux_stats stats;
struct kcm_psock_stats aggregate_psock_stats;
+ struct strp_aggr_stats aggregate_strp_stats;
/* Receive */
spinlock_t rx_lock ____cacheline_aligned_in_smp;
@@ -190,14 +173,6 @@ static inline void aggregate_psock_stats(struct kcm_psock_stats *stats,
/* Save psock statistics in the mux when psock is being unattached. */
#define SAVE_PSOCK_STATS(_stat) (agg_stats->_stat += stats->_stat)
- SAVE_PSOCK_STATS(rx_msgs);
- SAVE_PSOCK_STATS(rx_bytes);
- SAVE_PSOCK_STATS(rx_aborts);
- SAVE_PSOCK_STATS(rx_mem_fail);
- SAVE_PSOCK_STATS(rx_need_more_hdr);
- SAVE_PSOCK_STATS(rx_msg_too_big);
- SAVE_PSOCK_STATS(rx_msg_timeouts);
- SAVE_PSOCK_STATS(rx_bad_hdr_len);
SAVE_PSOCK_STATS(tx_msgs);
SAVE_PSOCK_STATS(tx_bytes);
SAVE_PSOCK_STATS(reserved);
diff --git a/include/net/strparser.h b/include/net/strparser.h
new file mode 100644
index 000000000000..fdb3d6746cc4
--- /dev/null
+++ b/include/net/strparser.h
@@ -0,0 +1,145 @@
+/*
+ * Stream Parser
+ *
+ * Copyright (c) 2016 Tom Herbert <tom@herbertland.com>
+ *
+ * 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.
+ */
+
+#ifndef __NET_STRPARSER_H_
+#define __NET_STRPARSER_H_
+
+#include <linux/skbuff.h>
+#include <net/sock.h>
+
+#define STRP_STATS_ADD(stat, count) ((stat) += (count))
+#define STRP_STATS_INCR(stat) ((stat)++)
+
+struct strp_stats {
+ unsigned long long rx_msgs;
+ unsigned long long rx_bytes;
+ unsigned int rx_mem_fail;
+ unsigned int rx_need_more_hdr;
+ unsigned int rx_msg_too_big;
+ unsigned int rx_msg_timeouts;
+ unsigned int rx_bad_hdr_len;
+};
+
+struct strp_aggr_stats {
+ unsigned long long rx_msgs;
+ unsigned long long rx_bytes;
+ unsigned int rx_mem_fail;
+ unsigned int rx_need_more_hdr;
+ unsigned int rx_msg_too_big;
+ unsigned int rx_msg_timeouts;
+ unsigned int rx_bad_hdr_len;
+ unsigned int rx_aborts;
+ unsigned int rx_interrupted;
+ unsigned int rx_unrecov_intr;
+};
+
+struct strparser;
+
+/* Callbacks are called with lock held for the attached socket */
+struct strp_callbacks {
+ int (*parse_msg)(struct strparser *strp, struct sk_buff *skb);
+ void (*rcv_msg)(struct strparser *strp, struct sk_buff *skb);
+ int (*read_sock_done)(struct strparser *strp, int err);
+ void (*abort_parser)(struct strparser *strp, int err);
+};
+
+struct strp_rx_msg {
+ int full_len;
+ int offset;
+};
+
+static inline struct strp_rx_msg *strp_rx_msg(struct sk_buff *skb)
+{
+ return (struct strp_rx_msg *)((void *)skb->cb +
+ offsetof(struct qdisc_skb_cb, data));
+}
+
+/* Structure for an attached lower socket */
+struct strparser {
+ struct sock *sk;
+
+ u32 rx_stopped : 1;
+ u32 rx_paused : 1;
+ u32 rx_aborted : 1;
+ u32 rx_interrupted : 1;
+ u32 rx_unrecov_intr : 1;
+
+ struct sk_buff **rx_skb_nextp;
+ struct timer_list rx_msg_timer;
+ struct sk_buff *rx_skb_head;
+ unsigned int rx_need_bytes;
+ struct delayed_work rx_delayed_work;
+ struct work_struct rx_work;
+ struct strp_stats stats;
+ struct strp_callbacks cb;
+};
+
+/* Must be called with lock held for attached socket */
+static inline void strp_pause(struct strparser *strp)
+{
+ strp->rx_paused = 1;
+}
+
+/* May be called without holding lock for attached socket */
+static inline void strp_unpause(struct strparser *strp)
+{
+ strp->rx_paused = 0;
+}
+
+static inline void save_strp_stats(struct strparser *strp,
+ struct strp_aggr_stats *agg_stats)
+{
+ /* Save psock statistics in the mux when psock is being unattached. */
+
+#define SAVE_PSOCK_STATS(_stat) (agg_stats->_stat += \
+ strp->stats._stat)
+ SAVE_PSOCK_STATS(rx_msgs);
+ SAVE_PSOCK_STATS(rx_bytes);
+ SAVE_PSOCK_STATS(rx_mem_fail);
+ SAVE_PSOCK_STATS(rx_need_more_hdr);
+ SAVE_PSOCK_STATS(rx_msg_too_big);
+ SAVE_PSOCK_STATS(rx_msg_timeouts);
+ SAVE_PSOCK_STATS(rx_bad_hdr_len);
+#undef SAVE_PSOCK_STATS
+
+ if (strp->rx_aborted)
+ agg_stats->rx_aborts++;
+ if (strp->rx_interrupted)
+ agg_stats->rx_interrupted++;
+ if (strp->rx_unrecov_intr)
+ agg_stats->rx_unrecov_intr++;
+}
+
+static inline void aggregate_strp_stats(struct strp_aggr_stats *stats,
+ struct strp_aggr_stats *agg_stats)
+{
+#define SAVE_PSOCK_STATS(_stat) (agg_stats->_stat += stats->_stat)
+ SAVE_PSOCK_STATS(rx_msgs);
+ SAVE_PSOCK_STATS(rx_bytes);
+ SAVE_PSOCK_STATS(rx_mem_fail);
+ SAVE_PSOCK_STATS(rx_need_more_hdr);
+ SAVE_PSOCK_STATS(rx_msg_too_big);
+ SAVE_PSOCK_STATS(rx_msg_timeouts);
+ SAVE_PSOCK_STATS(rx_bad_hdr_len);
+ SAVE_PSOCK_STATS(rx_aborts);
+ SAVE_PSOCK_STATS(rx_interrupted);
+ SAVE_PSOCK_STATS(rx_unrecov_intr);
+#undef SAVE_PSOCK_STATS
+
+}
+
+void strp_done(struct strparser *strp);
+void strp_stop(struct strparser *strp);
+void strp_check_rcv(struct strparser *strp);
+int strp_init(struct strparser *strp, struct sock *csk,
+ struct strp_callbacks *cb);
+void strp_tcp_data_ready(struct strparser *strp);
+
+#endif /* __NET_STRPARSER_H_ */
diff --git a/net/Kconfig b/net/Kconfig
index c2cdbce629bd..7b6cd340b72b 100644
--- a/net/Kconfig
+++ b/net/Kconfig
@@ -369,6 +369,7 @@ source "net/irda/Kconfig"
source "net/bluetooth/Kconfig"
source "net/rxrpc/Kconfig"
source "net/kcm/Kconfig"
+source "net/strparser/Kconfig"
config FIB_RULES
bool
diff --git a/net/Makefile b/net/Makefile
index 9bd20bb86cc6..4cafaa2b4667 100644
--- a/net/Makefile
+++ b/net/Makefile
@@ -35,6 +35,7 @@ obj-$(CONFIG_BT) += bluetooth/
obj-$(CONFIG_SUNRPC) += sunrpc/
obj-$(CONFIG_AF_RXRPC) += rxrpc/
obj-$(CONFIG_AF_KCM) += kcm/
+obj-$(CONFIG_STREAM_PARSER) += strparser/
obj-$(CONFIG_ATM) += atm/
obj-$(CONFIG_L2TP) += l2tp/
obj-$(CONFIG_DECNET) += decnet/
diff --git a/net/ipv6/ila/ila_common.c b/net/ipv6/ila/ila_common.c
index ec9efbcdad35..aba0998ddbfb 100644
--- a/net/ipv6/ila/ila_common.c
+++ b/net/ipv6/ila/ila_common.c
@@ -172,6 +172,5 @@ static void __exit ila_fini(void)
module_init(ila_init);
module_exit(ila_fini);
-MODULE_ALIAS_RTNL_LWT(ILA);
MODULE_AUTHOR("Tom Herbert <tom@herbertland.com>");
MODULE_LICENSE("GPL");
diff --git a/net/kcm/Kconfig b/net/kcm/Kconfig
index 5db94d940ecc..87fca36e6c47 100644
--- a/net/kcm/Kconfig
+++ b/net/kcm/Kconfig
@@ -3,6 +3,7 @@ config AF_KCM
tristate "KCM sockets"
depends on INET
select BPF_SYSCALL
+ select STREAM_PARSER
---help---
KCM (Kernel Connection Multiplexor) sockets provide a method
for multiplexing messages of a message based application
diff --git a/net/kcm/kcmproc.c b/net/kcm/kcmproc.c
index 16c2e03bd388..47e445364f4f 100644
--- a/net/kcm/kcmproc.c
+++ b/net/kcm/kcmproc.c
@@ -155,8 +155,8 @@ static void kcm_format_psock(struct kcm_psock *psock, struct seq_file *seq,
seq_printf(seq,
" psock-%-5u %-10llu %-16llu %-10llu %-16llu %-8d %-8d %-8d %-8d ",
psock->index,
- psock->stats.rx_msgs,
- psock->stats.rx_bytes,
+ psock->strp.stats.rx_msgs,
+ psock->strp.stats.rx_bytes,
psock->stats.tx_msgs,
psock->stats.tx_bytes,
psock->sk->sk_receive_queue.qlen,
@@ -170,9 +170,12 @@ static void kcm_format_psock(struct kcm_psock *psock, struct seq_file *seq,
if (psock->tx_stopped)
seq_puts(seq, "TxStop ");
- if (psock->rx_stopped)
+ if (psock->strp.rx_stopped)
seq_puts(seq, "RxStop ");
+ if (psock->strp.rx_paused)
+ seq_puts(seq, "RxPause ");
+
if (psock->tx_kcm)
seq_printf(seq, "Rsvd-%d ", psock->tx_kcm->index);
@@ -275,6 +278,7 @@ static int kcm_stats_seq_show(struct seq_file *seq, void *v)
{
struct kcm_psock_stats psock_stats;
struct kcm_mux_stats mux_stats;
+ struct strp_aggr_stats strp_stats;
struct kcm_mux *mux;
struct kcm_psock *psock;
struct net *net = seq->private;
@@ -282,20 +286,28 @@ static int kcm_stats_seq_show(struct seq_file *seq, void *v)
memset(&mux_stats, 0, sizeof(mux_stats));
memset(&psock_stats, 0, sizeof(psock_stats));
+ memset(&strp_stats, 0, sizeof(strp_stats));
mutex_lock(&knet->mutex);
aggregate_mux_stats(&knet->aggregate_mux_stats, &mux_stats);
aggregate_psock_stats(&knet->aggregate_psock_stats,
&psock_stats);
+ aggregate_strp_stats(&knet->aggregate_strp_stats,
+ &strp_stats);
list_for_each_entry_rcu(mux, &knet->mux_list, kcm_mux_list) {
spin_lock_bh(&mux->lock);
aggregate_mux_stats(&mux->stats, &mux_stats);
aggregate_psock_stats(&mux->aggregate_psock_stats,
&psock_stats);
- list_for_each_entry(psock, &mux->psocks, psock_list)
+ aggregate_strp_stats(&mux->aggregate_strp_stats,
+ &strp_stats);
+ list_for_each_entry(psock, &mux->psocks, psock_list) {
aggregate_psock_stats(&psock->stats, &psock_stats);
+ save_strp_stats(&psock->strp, &strp_stats);
+ }
+
spin_unlock_bh(&mux->lock);
}
@@ -328,7 +340,7 @@ static int kcm_stats_seq_show(struct seq_file *seq, void *v)
mux_stats.rx_ready_drops);
seq_printf(seq,
- "%-8s %-10s %-16s %-10s %-16s %-10s %-10s %-10s %-10s %-10s %-10s %-10s %-10s %-10s\n",
+ "%-8s %-10s %-16s %-10s %-16s %-10s %-10s %-10s %-10s %-10s %-10s %-10s %-10s %-10s %-10s %-10s\n",
"Psock",
"RX-Msgs",
"RX-Bytes",
@@ -337,6 +349,8 @@ static int kcm_stats_seq_show(struct seq_file *seq, void *v)
"Reserved",
"Unreserved",
"RX-Aborts",
+ "RX-Intr",
+ "RX-Unrecov",
"RX-MemFail",
"RX-NeedMor",
"RX-BadLen",
@@ -345,20 +359,22 @@ static int kcm_stats_seq_show(struct seq_file *seq, void *v)
"TX-Aborts");
seq_printf(seq,
- "%-8s %-10llu %-16llu %-10llu %-16llu %-10llu %-10llu %-10u %-10u %-10u %-10u %-10u %-10u %-10u\n",
+ "%-8s %-10llu %-16llu %-10llu %-16llu %-10llu %-10llu %-10u %-10u %-10u %-10u %-10u %-10u %-10u %-10u %-10u\n",
"",
- psock_stats.rx_msgs,
- psock_stats.rx_bytes,
+ strp_stats.rx_msgs,
+ strp_stats.rx_bytes,
psock_stats.tx_msgs,
psock_stats.tx_bytes,
psock_stats.reserved,
psock_stats.unreserved,
- psock_stats.rx_aborts,
- psock_stats.rx_mem_fail,
- psock_stats.rx_need_more_hdr,
- psock_stats.rx_bad_hdr_len,
- psock_stats.rx_msg_too_big,
- psock_stats.rx_msg_timeouts,
+ strp_stats.rx_aborts,
+ strp_stats.rx_interrupted,
+ strp_stats.rx_unrecov_intr,
+ strp_stats.rx_mem_fail,
+ strp_stats.rx_need_more_hdr,
+ strp_stats.rx_bad_hdr_len,
+ strp_stats.rx_msg_too_big,
+ strp_stats.rx_msg_timeouts,
psock_stats.tx_aborts);
return 0;
diff --git a/net/kcm/kcmsock.c b/net/kcm/kcmsock.c
index cb39e05b166c..eedbe404af35 100644
--- a/net/kcm/kcmsock.c
+++ b/net/kcm/kcmsock.c
@@ -1,3 +1,13 @@
+/*
+ * Kernel Connection Multiplexor
+ *
+ * Copyright (c) 2016 Tom Herbert <tom@herbertland.com>
+ *
+ * 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/bpf.h>
#include <linux/errno.h>
#include <linux/errqueue.h>
@@ -35,38 +45,12 @@ static inline struct kcm_tx_msg *kcm_tx_msg(struct sk_buff *skb)
return (struct kcm_tx_msg *)skb->cb;
}
-static inline struct kcm_rx_msg *kcm_rx_msg(struct sk_buff *skb)
-{
- return (struct kcm_rx_msg *)((void *)skb->cb +
- offsetof(struct qdisc_skb_cb, data));
-}
-
static void report_csk_error(struct sock *csk, int err)
{
csk->sk_err = EPIPE;
csk->sk_error_report(csk);
}
-/* Callback lock held */
-static void kcm_abort_rx_psock(struct kcm_psock *psock, int err,
- struct sk_buff *skb)
-{
- struct sock *csk = psock->sk;
-
- /* Unrecoverable error in receive */
-
- del_timer(&psock->rx_msg_timer);
-
- if (psock->rx_stopped)
- return;
-
- psock->rx_stopped = 1;
- KCM_STATS_INCR(psock->stats.rx_aborts);
-
- /* Report an error on the lower socket */
- report_csk_error(csk, err);
-}
-
static void kcm_abort_tx_psock(struct kcm_psock *psock, int err,
bool wakeup_kcm)
{
@@ -109,12 +93,13 @@ static void kcm_abort_tx_psock(struct kcm_psock *psock, int err,
static void kcm_update_rx_mux_stats(struct kcm_mux *mux,
struct kcm_psock *psock)
{
- KCM_STATS_ADD(mux->stats.rx_bytes,
- psock->stats.rx_bytes - psock->saved_rx_bytes);
+ STRP_STATS_ADD(mux->stats.rx_bytes,
+ psock->strp.stats.rx_bytes -
+ psock->saved_rx_bytes);
mux->stats.rx_msgs +=
- psock->stats.rx_msgs - psock->saved_rx_msgs;
- psock->saved_rx_msgs = psock->stats.rx_msgs;
- psock->saved_rx_bytes = psock->stats.rx_bytes;
+ psock->strp.stats.rx_msgs - psock->saved_rx_msgs;
+ psock->saved_rx_msgs = psock->strp.stats.rx_msgs;
+ psock->saved_rx_bytes = psock->strp.stats.rx_bytes;
}
static void kcm_update_tx_mux_stats(struct kcm_mux *mux,
@@ -167,11 +152,11 @@ static void kcm_rcv_ready(struct kcm_sock *kcm)
*/
list_del(&psock->psock_ready_list);
psock->ready_rx_msg = NULL;
-
/* Commit clearing of ready_rx_msg for queuing work */
smp_mb();
- queue_work(kcm_wq, &psock->rx_work);
+ strp_unpause(&psock->strp);
+ strp_check_rcv(&psock->strp);
}
/* Buffer limit is okay now, add to ready list */
@@ -285,6 +270,7 @@ static struct kcm_sock *reserve_rx_kcm(struct kcm_psock *psock,
if (list_empty(&mux->kcm_rx_waiters)) {
psock->ready_rx_msg = head;
+ strp_pause(&psock->strp);
list_add_tail(&psock->psock_ready_list,
&mux->psocks_ready);
spin_unlock_bh(&mux->rx_lock);
@@ -353,276 +339,6 @@ static void unreserve_rx_kcm(struct kcm_psock *psock,
spin_unlock_bh(&mux->rx_lock);
}
-static void kcm_start_rx_timer(struct kcm_psock *psock)
-{
- if (psock->sk->sk_rcvtimeo)
- mod_timer(&psock->rx_msg_timer, psock->sk->sk_rcvtimeo);
-}
-
-/* Macro to invoke filter function. */
-#define KCM_RUN_FILTER(prog, ctx) \
- (*prog->bpf_func)(ctx, prog->insnsi)
-
-/* Lower socket lock held */
-static int kcm_tcp_recv(read_descriptor_t *desc, struct sk_buff *orig_skb,
- unsigned int orig_offset, size_t orig_len)
-{
- struct kcm_psock *psock = (struct kcm_psock *)desc->arg.data;
- struct kcm_rx_msg *rxm;
- struct kcm_sock *kcm;
- struct sk_buff *head, *skb;
- size_t eaten = 0, cand_len;
- ssize_t extra;
- int err;
- bool cloned_orig = false;
-
- if (psock->ready_rx_msg)
- return 0;
-
- head = psock->rx_skb_head;
- if (head) {
- /* Message already in progress */
-
- rxm = kcm_rx_msg(head);
- if (unlikely(rxm->early_eaten)) {
- /* Already some number of bytes on the receive sock
- * data saved in rx_skb_head, just indicate they
- * are consumed.
- */
- eaten = orig_len <= rxm->early_eaten ?
- orig_len : rxm->early_eaten;
- rxm->early_eaten -= eaten;
-
- return eaten;
- }
-
- if (unlikely(orig_offset)) {
- /* Getting data with a non-zero offset when a message is
- * in progress is not expected. If it does happen, we
- * need to clone and pull since we can't deal with
- * offsets in the skbs for a message expect in the head.
- */
- orig_skb = skb_clone(orig_skb, GFP_ATOMIC);
- if (!orig_skb) {
- KCM_STATS_INCR(psock->stats.rx_mem_fail);
- desc->error = -ENOMEM;
- return 0;
- }
- if (!pskb_pull(orig_skb, orig_offset)) {
- KCM_STATS_INCR(psock->stats.rx_mem_fail);
- kfree_skb(orig_skb);
- desc->error = -ENOMEM;
- return 0;
- }
- cloned_orig = true;
- orig_offset = 0;
- }
-
- if (!psock->rx_skb_nextp) {
- /* We are going to append to the frags_list of head.
- * Need to unshare the frag_list.
- */
- err = skb_unclone(head, GFP_ATOMIC);
- if (err) {
- KCM_STATS_INCR(psock->stats.rx_mem_fail);
- desc->error = err;
- return 0;
- }
-
- if (unlikely(skb_shinfo(head)->frag_list)) {
- /* We can't append to an sk_buff that already
- * has a frag_list. We create a new head, point
- * the frag_list of that to the old head, and
- * then are able to use the old head->next for
- * appending to the message.
- */
- if (WARN_ON(head->next)) {
- desc->error = -EINVAL;
- return 0;
- }
-
- skb = alloc_skb(0, GFP_ATOMIC);
- if (!skb) {
- KCM_STATS_INCR(psock->stats.rx_mem_fail);
- desc->error = -ENOMEM;
- return 0;
- }
- skb->len = head->len;
- skb->data_len = head->len;
- skb->truesize = head->truesize;
- *kcm_rx_msg(skb) = *kcm_rx_msg(head);
- psock->rx_skb_nextp = &head->next;
- skb_shinfo(skb)->frag_list = head;
- psock->rx_skb_head = skb;
- head = skb;
- } else {
- psock->rx_skb_nextp =
- &skb_shinfo(head)->frag_list;
- }
- }
- }
-
- while (eaten < orig_len) {
- /* Always clone since we will consume something */
- skb = skb_clone(orig_skb, GFP_ATOMIC);
- if (!skb) {
- KCM_STATS_INCR(psock->stats.rx_mem_fail);
- desc->error = -ENOMEM;
- break;
- }
-
- cand_len = orig_len - eaten;
-
- head = psock->rx_skb_head;
- if (!head) {
- head = skb;
- psock->rx_skb_head = head;
- /* Will set rx_skb_nextp on next packet if needed */
- psock->rx_skb_nextp = NULL;
- rxm = kcm_rx_msg(head);
- memset(rxm, 0, sizeof(*rxm));
- rxm->offset = orig_offset + eaten;
- } else {
- /* Unclone since we may be appending to an skb that we
- * already share a frag_list with.
- */
- err = skb_unclone(skb, GFP_ATOMIC);
- if (err) {
- KCM_STATS_INCR(psock->stats.rx_mem_fail);
- desc->error = err;
- break;
- }
-
- rxm = kcm_rx_msg(head);
- *psock->rx_skb_nextp = skb;
- psock->rx_skb_nextp = &skb->next;
- head->data_len += skb->len;
- head->len += skb->len;
- head->truesize += skb->truesize;
- }
-
- if (!rxm->full_len) {
- ssize_t len;
-
- len = KCM_RUN_FILTER(psock->bpf_prog, head);
-
- if (!len) {
- /* Need more header to determine length */
- if (!rxm->accum_len) {
- /* Start RX timer for new message */
- kcm_start_rx_timer(psock);
- }
- rxm->accum_len += cand_len;
- eaten += cand_len;
- KCM_STATS_INCR(psock->stats.rx_need_more_hdr);
- WARN_ON(eaten != orig_len);
- break;
- } else if (len > psock->sk->sk_rcvbuf) {
- /* Message length exceeds maximum allowed */
- KCM_STATS_INCR(psock->stats.rx_msg_too_big);
- desc->error = -EMSGSIZE;
- psock->rx_skb_head = NULL;
- kcm_abort_rx_psock(psock, EMSGSIZE, head);
- break;
- } else if (len <= (ssize_t)head->len -
- skb->len - rxm->offset) {
- /* Length must be into new skb (and also
- * greater than zero)
- */
- KCM_STATS_INCR(psock->stats.rx_bad_hdr_len);
- desc->error = -EPROTO;
- psock->rx_skb_head = NULL;
- kcm_abort_rx_psock(psock, EPROTO, head);
- break;
- }
-
- rxm->full_len = len;
- }
-
- extra = (ssize_t)(rxm->accum_len + cand_len) - rxm->full_len;
-
- if (extra < 0) {
- /* Message not complete yet. */
- if (rxm->full_len - rxm->accum_len >
- tcp_inq(psock->sk)) {
- /* Don't have the whole messages in the socket
- * buffer. Set psock->rx_need_bytes to wait for
- * the rest of the message. Also, set "early
- * eaten" since we've already buffered the skb
- * but don't consume yet per tcp_read_sock.
- */
-
- if (!rxm->accum_len) {
- /* Start RX timer for new message */
- kcm_start_rx_timer(psock);
- }
-
- psock->rx_need_bytes = rxm->full_len -
- rxm->accum_len;
- rxm->accum_len += cand_len;
- rxm->early_eaten = cand_len;
- KCM_STATS_ADD(psock->stats.rx_bytes, cand_len);
- desc->count = 0; /* Stop reading socket */
- break;
- }
- rxm->accum_len += cand_len;
- eaten += cand_len;
- WARN_ON(eaten != orig_len);
- break;
- }
-
- /* Positive extra indicates ore bytes than needed for the
- * message
- */
-
- WARN_ON(extra > cand_len);
-
- eaten += (cand_len - extra);
-
- /* Hurray, we have a new message! */
- del_timer(&psock->rx_msg_timer);
- psock->rx_skb_head = NULL;
- KCM_STATS_INCR(psock->stats.rx_msgs);
-
-try_queue:
- kcm = reserve_rx_kcm(psock, head);
- if (!kcm) {
- /* Unable to reserve a KCM, message is held in psock. */
- break;
- }
-
- if (kcm_queue_rcv_skb(&kcm->sk, head)) {
- /* Should mean socket buffer full */
- unreserve_rx_kcm(psock, false);
- goto try_queue;
- }
- }
-
- if (cloned_orig)
- kfree_skb(orig_skb);
-
- KCM_STATS_ADD(psock->stats.rx_bytes, eaten);
-
- return eaten;
-}
-
-/* Called with lock held on lower socket */
-static int psock_tcp_read_sock(struct kcm_psock *psock)
-{
- read_descriptor_t desc;
-
- desc.arg.data = psock;
- desc.error = 0;
- desc.count = 1; /* give more than one skb per call */
-
- /* sk should be locked here, so okay to do tcp_read_sock */
- tcp_read_sock(psock->sk, &desc, kcm_tcp_recv);
-
- unreserve_rx_kcm(psock, true);
-
- return desc.error;
-}
-
/* Lower sock lock held */
static void psock_tcp_data_ready(struct sock *sk)
{
@@ -631,65 +347,49 @@ static void psock_tcp_data_ready(struct sock *sk)
read_lock_bh(&sk->sk_callback_lock);
psock = (struct kcm_psock *)sk->sk_user_data;
- if (unlikely(!psock || psock->rx_stopped))
- goto out;
-
- if (psock->ready_rx_msg)
- goto out;
-
- if (psock->rx_need_bytes) {
- if (tcp_inq(sk) >= psock->rx_need_bytes)
- psock->rx_need_bytes = 0;
- else
- goto out;
- }
-
- if (psock_tcp_read_sock(psock) == -ENOMEM)
- queue_delayed_work(kcm_wq, &psock->rx_delayed_work, 0);
+ if (likely(psock))
+ strp_tcp_data_ready(&psock->strp);
-out:
read_unlock_bh(&sk->sk_callback_lock);
}
-static void do_psock_rx_work(struct kcm_psock *psock)
+/* Called with lower sock held */
+static void kcm_rcv_strparser(struct strparser *strp, struct sk_buff *skb)
{
- read_descriptor_t rd_desc;
- struct sock *csk = psock->sk;
-
- /* We need the read lock to synchronize with psock_tcp_data_ready. We
- * need the socket lock for calling tcp_read_sock.
- */
- lock_sock(csk);
- read_lock_bh(&csk->sk_callback_lock);
-
- if (unlikely(csk->sk_user_data != psock))
- goto out;
-
- if (unlikely(psock->rx_stopped))
- goto out;
-
- if (psock->ready_rx_msg)
- goto out;
-
- rd_desc.arg.data = psock;
+ struct kcm_psock *psock = container_of(strp, struct kcm_psock, strp);
+ struct kcm_sock *kcm;
- if (psock_tcp_read_sock(psock) == -ENOMEM)
- queue_delayed_work(kcm_wq, &psock->rx_delayed_work, 0);
+try_queue:
+ kcm = reserve_rx_kcm(psock, skb);
+ if (!kcm) {
+ /* Unable to reserve a KCM, message is held in psock and strp
+ * is paused.
+ */
+ return;
+ }
-out:
- read_unlock_bh(&csk->sk_callback_lock);
- release_sock(csk);
+ if (kcm_queue_rcv_skb(&kcm->sk, skb)) {
+ /* Should mean socket buffer full */
+ unreserve_rx_kcm(psock, false);
+ goto try_queue;
+ }
}
-static void psock_rx_work(struct work_struct *w)
+static int kcm_parse_func_strparser(struct strparser *strp, struct sk_buff *skb)
{
- do_psock_rx_work(container_of(w, struct kcm_psock, rx_work));
+ struct kcm_psock *psock = container_of(strp, struct kcm_psock, strp);
+ struct bpf_prog *prog = psock->bpf_prog;
+
+ return (*prog->bpf_func)(skb, prog->insnsi);
}
-static void psock_rx_delayed_work(struct work_struct *w)
+static int kcm_read_sock_done(struct strparser *strp, int err)
{
- do_psock_rx_work(container_of(w, struct kcm_psock,
- rx_delayed_work.work));
+ struct kcm_psock *psock = container_of(strp, struct kcm_psock, strp);
+
+ unreserve_rx_kcm(psock, true);
+
+ return err;
}
static void psock_tcp_state_change(struct sock *sk)
@@ -713,14 +413,13 @@ static void psock_tcp_write_space(struct sock *sk)
psock = (struct kcm_psock *)sk->sk_user_data;
if (unlikely(!psock))
goto out;
-
mux = psock->mux;
spin_lock_bh(&mux->lock);
/* Check if the socket is reserved so someone is waiting for sending. */
kcm = psock->tx_kcm;
- if (kcm)
+ if (kcm && !unlikely(kcm->tx_stopped))
queue_work(kcm_wq, &kcm->tx_work);
spin_unlock_bh(&mux->lock);
@@ -1411,7 +1110,7 @@ static int kcm_recvmsg(struct socket *sock, struct msghdr *msg,
struct kcm_sock *kcm = kcm_sk(sk);
int err = 0;
long timeo;
- struct kcm_rx_msg *rxm;
+ struct strp_rx_msg *rxm;
int copied = 0;
struct sk_buff *skb;
@@ -1425,7 +1124,7 @@ static int kcm_recvmsg(struct socket *sock, struct msghdr *msg,
/* Okay, have a message on the receive queue */
- rxm = kcm_rx_msg(skb);
+ rxm = strp_rx_msg(skb);
if (len > rxm->full_len)
len = rxm->full_len;
@@ -1481,7 +1180,7 @@ static ssize_t kcm_splice_read(struct socket *sock, loff_t *ppos,
struct sock *sk = sock->sk;
struct kcm_sock *kcm = kcm_sk(sk);
long timeo;
- struct kcm_rx_msg *rxm;
+ struct strp_rx_msg *rxm;
int err = 0;
ssize_t copied;
struct sk_buff *skb;
@@ -1498,7 +1197,7 @@ static ssize_t kcm_splice_read(struct socket *sock, loff_t *ppos,
/* Okay, have a message on the receive queue */
- rxm = kcm_rx_msg(skb);
+ rxm = strp_rx_msg(skb);
if (len > rxm->full_len)
len = rxm->full_len;
@@ -1674,15 +1373,6 @@ static void init_kcm_sock(struct kcm_sock *kcm, struct kcm_mux *mux)
spin_unlock_bh(&mux->rx_lock);
}
-static void kcm_rx_msg_timeout(unsigned long arg)
-{
- struct kcm_psock *psock = (struct kcm_psock *)arg;
-
- /* Message assembly timed out */
- KCM_STATS_INCR(psock->stats.rx_msg_timeouts);
- kcm_abort_rx_psock(psock, ETIMEDOUT, NULL);
-}
-
static int kcm_attach(struct socket *sock, struct socket *csock,
struct bpf_prog *prog)
{
@@ -1692,6 +1382,7 @@ static int kcm_attach(struct socket *sock, struct socket *csock,
struct kcm_psock *psock = NULL, *tpsock;
struct list_head *head;
int index = 0;
+ struct strp_callbacks cb;
if (csock->ops->family != PF_INET &&
csock->ops->family != PF_INET6)
@@ -1713,11 +1404,12 @@ static int kcm_attach(struct socket *sock, struct socket *csock,
psock->sk = csk;
psock->bpf_prog = prog;
- setup_timer(&psock->rx_msg_timer, kcm_rx_msg_timeout,
- (unsigned long)psock);
+ cb.rcv_msg = kcm_rcv_strparser;
+ cb.abort_parser = NULL;
+ cb.parse_msg = kcm_parse_func_strparser;
+ cb.read_sock_done = kcm_read_sock_done;
- INIT_WORK(&psock->rx_work, psock_rx_work);
- INIT_DELAYED_WORK(&psock->rx_delayed_work, psock_rx_delayed_work);
+ strp_init(&psock->strp, csk, &cb);
sock_hold(csk);
@@ -1750,7 +1442,7 @@ static int kcm_attach(struct socket *sock, struct socket *csock,
spin_unlock_bh(&mux->lock);
/* Schedule RX work in case there are already bytes queued */
- queue_work(kcm_wq, &psock->rx_work);
+ strp_check_rcv(&psock->strp);
return 0;
}
@@ -1785,6 +1477,7 @@ out:
return err;
}
+/* Lower socket lock held */
static void kcm_unattach(struct kcm_psock *psock)
{
struct sock *csk = psock->sk;
@@ -1798,7 +1491,7 @@ static void kcm_unattach(struct kcm_psock *psock)
csk->sk_data_ready = psock->save_data_ready;
csk->sk_write_space = psock->save_write_space;
csk->sk_state_change = psock->save_state_change;
- psock->rx_stopped = 1;
+ strp_stop(&psock->strp);
if (WARN_ON(psock->rx_kcm)) {
write_unlock_bh(&csk->sk_callback_lock);
@@ -1821,18 +1514,14 @@ static void kcm_unattach(struct kcm_psock *psock)
write_unlock_bh(&csk->sk_callback_lock);
- del_timer_sync(&psock->rx_msg_timer);
- cancel_work_sync(&psock->rx_work);
- cancel_delayed_work_sync(&psock->rx_delayed_work);
+ strp_done(&psock->strp);
bpf_prog_put(psock->bpf_prog);
- kfree_skb(psock->rx_skb_head);
- psock->rx_skb_head = NULL;
-
spin_lock_bh(&mux->lock);
aggregate_psock_stats(&psock->stats, &mux->aggregate_psock_stats);
+ save_strp_stats(&psock->strp, &mux->aggregate_strp_stats);
KCM_STATS_INCR(mux->stats.psock_unattach);
@@ -1915,6 +1604,7 @@ static int kcm_unattach_ioctl(struct socket *sock, struct kcm_unattach *info)
spin_unlock_bh(&mux->lock);
+ /* Lower socket lock should already be held */
kcm_unattach(psock);
err = 0;
@@ -2059,8 +1749,11 @@ static void release_mux(struct kcm_mux *mux)
/* Release psocks */
list_for_each_entry_safe(psock, tmp_psock,
&mux->psocks, psock_list) {
- if (!WARN_ON(psock->unattaching))
+ if (!WARN_ON(psock->unattaching)) {
+ lock_sock(psock->strp.sk);
kcm_unattach(psock);
+ release_sock(psock->strp.sk);
+ }
}
if (WARN_ON(mux->psocks_cnt))
@@ -2072,6 +1765,8 @@ static void release_mux(struct kcm_mux *mux)
aggregate_mux_stats(&mux->stats, &knet->aggregate_mux_stats);
aggregate_psock_stats(&mux->aggregate_psock_stats,
&knet->aggregate_psock_stats);
+ aggregate_strp_stats(&mux->aggregate_strp_stats,
+ &knet->aggregate_strp_stats);
list_del_rcu(&mux->kcm_mux_list);
knet->count--;
mutex_unlock(&knet->mutex);
@@ -2151,6 +1846,13 @@ static int kcm_release(struct socket *sock)
* it will just return.
*/
__skb_queue_purge(&sk->sk_write_queue);
+
+ /* Set tx_stopped. This is checked when psock is bound to a kcm and we
+ * get a writespace callback. This prevents further work being queued
+ * from the callback (unbinding the psock occurs after canceling work.
+ */
+ kcm->tx_stopped = 1;
+
release_sock(sk);
spin_lock_bh(&mux->lock);
diff --git a/net/strparser/Kconfig b/net/strparser/Kconfig
new file mode 100644
index 000000000000..6cff3f6d0c3a
--- /dev/null
+++ b/net/strparser/Kconfig
@@ -0,0 +1,4 @@
+
+config STREAM_PARSER
+ tristate
+ default n
diff --git a/net/strparser/Makefile b/net/strparser/Makefile
new file mode 100644
index 000000000000..858a126ebaa0
--- /dev/null
+++ b/net/strparser/Makefile
@@ -0,0 +1 @@
+obj-$(CONFIG_STREAM_PARSER) += strparser.o
diff --git a/net/strparser/strparser.c b/net/strparser/strparser.c
new file mode 100644
index 000000000000..fd688c0a7744
--- /dev/null
+++ b/net/strparser/strparser.c
@@ -0,0 +1,492 @@
+/*
+ * Stream Parser
+ *
+ * Copyright (c) 2016 Tom Herbert <tom@herbertland.com>
+ *
+ * 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/bpf.h>
+#include <linux/errno.h>
+#include <linux/errqueue.h>
+#include <linux/file.h>
+#include <linux/in.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/net.h>
+#include <linux/netdevice.h>
+#include <linux/poll.h>
+#include <linux/rculist.h>
+#include <linux/skbuff.h>
+#include <linux/socket.h>
+#include <linux/uaccess.h>
+#include <linux/workqueue.h>
+#include <net/strparser.h>
+#include <net/netns/generic.h>
+#include <net/sock.h>
+#include <net/tcp.h>
+
+static struct workqueue_struct *strp_wq;
+
+struct _strp_rx_msg {
+ /* Internal cb structure. struct strp_rx_msg must be first for passing
+ * to upper layer.
+ */
+ struct strp_rx_msg strp;
+ int accum_len;
+ int early_eaten;
+};
+
+static inline struct _strp_rx_msg *_strp_rx_msg(struct sk_buff *skb)
+{
+ return (struct _strp_rx_msg *)((void *)skb->cb +
+ offsetof(struct qdisc_skb_cb, data));
+}
+
+/* Lower lock held */
+static void strp_abort_rx_strp(struct strparser *strp, int err)
+{
+ struct sock *csk = strp->sk;
+
+ /* Unrecoverable error in receive */
+
+ del_timer(&strp->rx_msg_timer);
+
+ if (strp->rx_stopped)
+ return;
+
+ strp->rx_stopped = 1;
+
+ /* Report an error on the lower socket */
+ csk->sk_err = err;
+ csk->sk_error_report(csk);
+}
+
+static void strp_start_rx_timer(struct strparser *strp)
+{
+ if (strp->sk->sk_rcvtimeo)
+ mod_timer(&strp->rx_msg_timer, strp->sk->sk_rcvtimeo);
+}
+
+/* Lower lock held */
+static void strp_parser_err(struct strparser *strp, int err,
+ read_descriptor_t *desc)
+{
+ desc->error = err;
+ kfree_skb(strp->rx_skb_head);
+ strp->rx_skb_head = NULL;
+ strp->cb.abort_parser(strp, err);
+}
+
+/* Lower socket lock held */
+static int strp_tcp_recv(read_descriptor_t *desc, struct sk_buff *orig_skb,
+ unsigned int orig_offset, size_t orig_len)
+{
+ struct strparser *strp = (struct strparser *)desc->arg.data;
+ struct _strp_rx_msg *rxm;
+ struct sk_buff *head, *skb;
+ size_t eaten = 0, cand_len;
+ ssize_t extra;
+ int err;
+ bool cloned_orig = false;
+
+ if (strp->rx_paused)
+ return 0;
+
+ head = strp->rx_skb_head;
+ if (head) {
+ /* Message already in progress */
+
+ rxm = _strp_rx_msg(head);
+ if (unlikely(rxm->early_eaten)) {
+ /* Already some number of bytes on the receive sock
+ * data saved in rx_skb_head, just indicate they
+ * are consumed.
+ */
+ eaten = orig_len <= rxm->early_eaten ?
+ orig_len : rxm->early_eaten;
+ rxm->early_eaten -= eaten;
+
+ return eaten;
+ }
+
+ if (unlikely(orig_offset)) {
+ /* Getting data with a non-zero offset when a message is
+ * in progress is not expected. If it does happen, we
+ * need to clone and pull since we can't deal with
+ * offsets in the skbs for a message expect in the head.
+ */
+ orig_skb = skb_clone(orig_skb, GFP_ATOMIC);
+ if (!orig_skb) {
+ STRP_STATS_INCR(strp->stats.rx_mem_fail);
+ desc->error = -ENOMEM;
+ return 0;
+ }
+ if (!pskb_pull(orig_skb, orig_offset)) {
+ STRP_STATS_INCR(strp->stats.rx_mem_fail);
+ kfree_skb(orig_skb);
+ desc->error = -ENOMEM;
+ return 0;
+ }
+ cloned_orig = true;
+ orig_offset = 0;
+ }
+
+ if (!strp->rx_skb_nextp) {
+ /* We are going to append to the frags_list of head.
+ * Need to unshare the frag_list.
+ */
+ err = skb_unclone(head, GFP_ATOMIC);
+ if (err) {
+ STRP_STATS_INCR(strp->stats.rx_mem_fail);
+ desc->error = err;
+ return 0;
+ }
+
+ if (unlikely(skb_shinfo(head)->frag_list)) {
+ /* We can't append to an sk_buff that already
+ * has a frag_list. We create a new head, point
+ * the frag_list of that to the old head, and
+ * then are able to use the old head->next for
+ * appending to the message.
+ */
+ if (WARN_ON(head->next)) {
+ desc->error = -EINVAL;
+ return 0;
+ }
+
+ skb = alloc_skb(0, GFP_ATOMIC);
+ if (!skb) {
+ STRP_STATS_INCR(strp->stats.rx_mem_fail);
+ desc->error = -ENOMEM;
+ return 0;
+ }
+ skb->len = head->len;
+ skb->data_len = head->len;
+ skb->truesize = head->truesize;
+ *_strp_rx_msg(skb) = *_strp_rx_msg(head);
+ strp->rx_skb_nextp = &head->next;
+ skb_shinfo(skb)->frag_list = head;
+ strp->rx_skb_head = skb;
+ head = skb;
+ } else {
+ strp->rx_skb_nextp =
+ &skb_shinfo(head)->frag_list;
+ }
+ }
+ }
+
+ while (eaten < orig_len) {
+ /* Always clone since we will consume something */
+ skb = skb_clone(orig_skb, GFP_ATOMIC);
+ if (!skb) {
+ STRP_STATS_INCR(strp->stats.rx_mem_fail);
+ desc->error = -ENOMEM;
+ break;
+ }
+
+ cand_len = orig_len - eaten;
+
+ head = strp->rx_skb_head;
+ if (!head) {
+ head = skb;
+ strp->rx_skb_head = head;
+ /* Will set rx_skb_nextp on next packet if needed */
+ strp->rx_skb_nextp = NULL;
+ rxm = _strp_rx_msg(head);
+ memset(rxm, 0, sizeof(*rxm));
+ rxm->strp.offset = orig_offset + eaten;
+ } else {
+ /* Unclone since we may be appending to an skb that we
+ * already share a frag_list with.
+ */
+ err = skb_unclone(skb, GFP_ATOMIC);
+ if (err) {
+ STRP_STATS_INCR(strp->stats.rx_mem_fail);
+ desc->error = err;
+ break;
+ }
+
+ rxm = _strp_rx_msg(head);
+ *strp->rx_skb_nextp = skb;
+ strp->rx_skb_nextp = &skb->next;
+ head->data_len += skb->len;
+ head->len += skb->len;
+ head->truesize += skb->truesize;
+ }
+
+ if (!rxm->strp.full_len) {
+ ssize_t len;
+
+ len = (*strp->cb.parse_msg)(strp, head);
+
+ if (!len) {
+ /* Need more header to determine length */
+ if (!rxm->accum_len) {
+ /* Start RX timer for new message */
+ strp_start_rx_timer(strp);
+ }
+ rxm->accum_len += cand_len;
+ eaten += cand_len;
+ STRP_STATS_INCR(strp->stats.rx_need_more_hdr);
+ WARN_ON(eaten != orig_len);
+ break;
+ } else if (len < 0) {
+ if (len == -ESTRPIPE && rxm->accum_len) {
+ len = -ENODATA;
+ strp->rx_unrecov_intr = 1;
+ } else {
+ strp->rx_interrupted = 1;
+ }
+ strp_parser_err(strp, err, desc);
+ break;
+ } else if (len > strp->sk->sk_rcvbuf) {
+ /* Message length exceeds maximum allowed */
+ STRP_STATS_INCR(strp->stats.rx_msg_too_big);
+ strp_parser_err(strp, -EMSGSIZE, desc);
+ break;
+ } else if (len <= (ssize_t)head->len -
+ skb->len - rxm->strp.offset) {
+ /* Length must be into new skb (and also
+ * greater than zero)
+ */
+ STRP_STATS_INCR(strp->stats.rx_bad_hdr_len);
+ strp_parser_err(strp, -EPROTO, desc);
+ break;
+ }
+
+ rxm->strp.full_len = len;
+ }
+
+ extra = (ssize_t)(rxm->accum_len + cand_len) -
+ rxm->strp.full_len;
+
+ if (extra < 0) {
+ /* Message not complete yet. */
+ if (rxm->strp.full_len - rxm->accum_len >
+ tcp_inq(strp->sk)) {
+ /* Don't have the whole messages in the socket
+ * buffer. Set strp->rx_need_bytes to wait for
+ * the rest of the message. Also, set "early
+ * eaten" since we've already buffered the skb
+ * but don't consume yet per tcp_read_sock.
+ */
+
+ if (!rxm->accum_len) {
+ /* Start RX timer for new message */
+ strp_start_rx_timer(strp);
+ }
+
+ strp->rx_need_bytes = rxm->strp.full_len -
+ rxm->accum_len;
+ rxm->accum_len += cand_len;
+ rxm->early_eaten = cand_len;
+ STRP_STATS_ADD(strp->stats.rx_bytes, cand_len);
+ desc->count = 0; /* Stop reading socket */
+ break;
+ }
+ rxm->accum_len += cand_len;
+ eaten += cand_len;
+ WARN_ON(eaten != orig_len);
+ break;
+ }
+
+ /* Positive extra indicates ore bytes than needed for the
+ * message
+ */
+
+ WARN_ON(extra > cand_len);
+
+ eaten += (cand_len - extra);
+
+ /* Hurray, we have a new message! */
+ del_timer(&strp->rx_msg_timer);
+ strp->rx_skb_head = NULL;
+ STRP_STATS_INCR(strp->stats.rx_msgs);
+
+ /* Give skb to upper layer */
+ strp->cb.rcv_msg(strp, head);
+
+ if (unlikely(strp->rx_paused)) {
+ /* Upper layer paused strp */
+ break;
+ }
+ }
+
+ if (cloned_orig)
+ kfree_skb(orig_skb);
+
+ STRP_STATS_ADD(strp->stats.rx_bytes, eaten);
+
+ return eaten;
+}
+
+static int default_read_sock_done(struct strparser *strp, int err)
+{
+ return err;
+}
+
+/* Called with lock held on lower socket */
+static int strp_tcp_read_sock(struct strparser *strp)
+{
+ read_descriptor_t desc;
+
+ desc.arg.data = strp;
+ desc.error = 0;
+ desc.count = 1; /* give more than one skb per call */
+
+ /* sk should be locked here, so okay to do tcp_read_sock */
+ tcp_read_sock(strp->sk, &desc, strp_tcp_recv);
+
+ desc.error = strp->cb.read_sock_done(strp, desc.error);
+
+ return desc.error;
+}
+
+/* Lower sock lock held */
+void strp_tcp_data_ready(struct strparser *strp)
+{
+ struct sock *csk = strp->sk;
+
+ if (unlikely(strp->rx_stopped))
+ return;
+
+ /* This check is needed to synchronize with do_strp_rx_work.
+ * do_strp_rx_work acquires a process lock (lock_sock) whereas
+ * the lock held here is bh_lock_sock. The two locks can be
+ * held by different threads at the same time, but bh_lock_sock
+ * allows a thread in BH context to safely check if the process
+ * lock is held. In this case, if the lock is held, queue work.
+ */
+ if (sock_owned_by_user(csk)) {
+ queue_work(strp_wq, &strp->rx_work);
+ return;
+ }
+
+ if (strp->rx_paused)
+ return;
+
+ if (strp->rx_need_bytes) {
+ if (tcp_inq(csk) >= strp->rx_need_bytes)
+ strp->rx_need_bytes = 0;
+ else
+ return;
+ }
+
+ if (strp_tcp_read_sock(strp) == -ENOMEM)
+ queue_work(strp_wq, &strp->rx_work);
+}
+EXPORT_SYMBOL_GPL(strp_tcp_data_ready);
+
+static void do_strp_rx_work(struct strparser *strp)
+{
+ read_descriptor_t rd_desc;
+ struct sock *csk = strp->sk;
+
+ /* We need the read lock to synchronize with strp_tcp_data_ready. We
+ * need the socket lock for calling tcp_read_sock.
+ */
+ lock_sock(csk);
+
+ if (unlikely(csk->sk_user_data != strp))
+ goto out;
+
+ if (unlikely(strp->rx_stopped))
+ goto out;
+
+ if (strp->rx_paused)
+ goto out;
+
+ rd_desc.arg.data = strp;
+
+ if (strp_tcp_read_sock(strp) == -ENOMEM)
+ queue_work(strp_wq, &strp->rx_work);
+
+out:
+ release_sock(csk);
+}
+
+static void strp_rx_work(struct work_struct *w)
+{
+ do_strp_rx_work(container_of(w, struct strparser, rx_work));
+}
+
+static void strp_rx_msg_timeout(unsigned long arg)
+{
+ struct strparser *strp = (struct strparser *)arg;
+
+ /* Message assembly timed out */
+ STRP_STATS_INCR(strp->stats.rx_msg_timeouts);
+ lock_sock(strp->sk);
+ strp->cb.abort_parser(strp, ETIMEDOUT);
+ release_sock(strp->sk);
+}
+
+int strp_init(struct strparser *strp, struct sock *csk,
+ struct strp_callbacks *cb)
+{
+ if (!cb || !cb->rcv_msg || !cb->parse_msg)
+ return -EINVAL;
+
+ memset(strp, 0, sizeof(*strp));
+
+ strp->sk = csk;
+
+ setup_timer(&strp->rx_msg_timer, strp_rx_msg_timeout,
+ (unsigned long)strp);
+
+ INIT_WORK(&strp->rx_work, strp_rx_work);
+
+ strp->cb.rcv_msg = cb->rcv_msg;
+ strp->cb.parse_msg = cb->parse_msg;
+ strp->cb.read_sock_done = cb->read_sock_done ? : default_read_sock_done;
+ strp->cb.abort_parser = cb->abort_parser ? : strp_abort_rx_strp;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(strp_init);
+
+/* strp must already be stopped so that strp_tcp_recv will no longer be called.
+ * Note that strp_done is not called with the lower socket held.
+ */
+void strp_done(struct strparser *strp)
+{
+ WARN_ON(!strp->rx_stopped);
+
+ del_timer_sync(&strp->rx_msg_timer);
+ cancel_work_sync(&strp->rx_work);
+
+ if (strp->rx_skb_head) {
+ kfree_skb(strp->rx_skb_head);
+ strp->rx_skb_head = NULL;
+ }
+}
+EXPORT_SYMBOL_GPL(strp_done);
+
+void strp_stop(struct strparser *strp)
+{
+ strp->rx_stopped = 1;
+}
+EXPORT_SYMBOL_GPL(strp_stop);
+
+void strp_check_rcv(struct strparser *strp)
+{
+ queue_work(strp_wq, &strp->rx_work);
+}
+EXPORT_SYMBOL_GPL(strp_check_rcv);
+
+static int __init strp_mod_init(void)
+{
+ strp_wq = create_singlethread_workqueue("kstrp");
+
+ return 0;
+}
+
+static void __exit strp_mod_exit(void)
+{
+}
+module_init(strp_mod_init);
+module_exit(strp_mod_exit);
+MODULE_LICENSE("GPL");
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-28 14:32:02 +0000