[U-Boot,v4,1/3] net: introduce packet capture support
diff mbox series

Message ID 20190718184333.27927-1-rfried.dev@gmail.com
State Accepted
Commit 3eaac6307d
Delegated to: Joe Hershberger
Headers show
Series
  • [U-Boot,v4,1/3] net: introduce packet capture support
Related show

Commit Message

Ramon Fried July 18, 2019, 6:43 p.m. UTC
Add support for capturing ethernet packets and storing
them in memory in PCAP(2.4) format, later to be analyzed by
any PCAP viewer software (IE. Wireshark)

This feature greatly assist debugging network issues such
as detecting dropped packets, packet corruption etc.

Signed-off-by: Ramon Fried <rfried.dev@gmail.com>
Reviewed-by: Alex Marginean <alexm.osslist@gmail.com>
Tested-by: Alex Marginean <alexm.osslist@gmail.com>

---

Changes in v4:
* Move implementation to pcap.c/pcap.h
* Display error message when memory is exhausted.
* Populate $pcapsize environment variable with actual capture
  size.
* move outgoing pcap_post to eth_send()

Changes in v3:
* Change to implementation to command based.
* Added counters for incoming/outgoing packets.
* Support clearing the capture for multiple captures.
* Added documentation (separate patch).

Changes in v2:
Fix type assignmnet to header.ts_sec

 cmd/Kconfig        |   7 ++
 cmd/Makefile       |   1 +
 cmd/pcap.c         |  71 +++++++++++++++++++++
 include/net/pcap.h |  55 ++++++++++++++++
 net/Makefile       |   1 +
 net/eth-uclass.c   |   7 ++
 net/eth_legacy.c   |  12 +++-
 net/net.c          |  11 ++++
 net/pcap.c         | 156 +++++++++++++++++++++++++++++++++++++++++++++
 9 files changed, 320 insertions(+), 1 deletion(-)
 create mode 100644 cmd/pcap.c
 create mode 100644 include/net/pcap.h
 create mode 100644 net/pcap.c

Comments

Joe Hershberger July 18, 2019, 9:37 p.m. UTC | #1
On Thu, Jul 18, 2019 at 1:44 PM Ramon Fried <rfried.dev@gmail.com> wrote:
>
> Add support for capturing ethernet packets and storing
> them in memory in PCAP(2.4) format, later to be analyzed by
> any PCAP viewer software (IE. Wireshark)
>
> This feature greatly assist debugging network issues such
> as detecting dropped packets, packet corruption etc.
>
> Signed-off-by: Ramon Fried <rfried.dev@gmail.com>
> Reviewed-by: Alex Marginean <alexm.osslist@gmail.com>
> Tested-by: Alex Marginean <alexm.osslist@gmail.com>

Acked-by: Joe Hershberger <joe.hershberger@ni.com>
Joe Hershberger July 23, 2019, 12:01 a.m. UTC | #2
On Thu, Jul 18, 2019 at 1:44 PM Ramon Fried <rfried.dev@gmail.com> wrote:
>
> Add support for capturing ethernet packets and storing
> them in memory in PCAP(2.4) format, later to be analyzed by
> any PCAP viewer software (IE. Wireshark)
>
> This feature greatly assist debugging network issues such
> as detecting dropped packets, packet corruption etc.
>
> Signed-off-by: Ramon Fried <rfried.dev@gmail.com>
> Reviewed-by: Alex Marginean <alexm.osslist@gmail.com>
> Tested-by: Alex Marginean <alexm.osslist@gmail.com>
>
> ---
>
> Changes in v4:
> * Move implementation to pcap.c/pcap.h
> * Display error message when memory is exhausted.
> * Populate $pcapsize environment variable with actual capture
>   size.
> * move outgoing pcap_post to eth_send()
>
> Changes in v3:
> * Change to implementation to command based.
> * Added counters for incoming/outgoing packets.
> * Support clearing the capture for multiple captures.
> * Added documentation (separate patch).
>
> Changes in v2:
> Fix type assignmnet to header.ts_sec

[ ... ]

> diff --git a/net/pcap.c b/net/pcap.c
> new file mode 100644
> index 0000000000..4036d8a3fa
> --- /dev/null
> +++ b/net/pcap.c
> @@ -0,0 +1,156 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Copyright 2019 Ramon Fried <rfried.dev@gmail.com>
> + */
> +
> +#include <common.h>
> +#include <net.h>
> +#include <net/pcap.h>
> +#include <time.h>
> +#include <asm/io.h>
> +
> +#define LINKTYPE_ETHERNET      1
> +
> +static bool initialized;
> +static bool running;
> +static bool buffer_full;
> +static void *buf;
> +static unsigned int max_size;
> +static unsigned int pos;
> +
> +static unsigned long incoming_count;
> +static unsigned long outgoing_count;
> +
> +struct pcap_header {
> +       u32 magic;
> +       u16 version_major;
> +       u16 version_minor;
> +       s32 thiszone;
> +       u32 sigfigs;
> +       u32 snaplen;
> +       u32 network;
> +};
> +
> +struct pcap_packet_header {
> +       u32 ts_sec;
> +       u32 ts_usec;
> +       u32 incl_len;
> +       u32 orig_len;
> +};
> +
> +static struct pcap_header file_header = {
> +       .magic = 0xa1b2c3d4,
> +       .version_major = 2,
> +       .version_minor = 4,
> +       .snaplen = 65535,
> +       .network = LINKTYPE_ETHERNET,
> +};
> +
> +int pcap_init(phys_addr_t paddr, unsigned long size)
> +{
> +       buf = map_physmem(paddr, size, 0);

Since this is mapping to physmem, and apparently from your
documentation, you need to use the physical memory when writing to a
file or tftp send, how is the mapping typically handled? Maybe we
should be writing to a variable like "pcapaddr" so it can be used in
the write as part of a script.

> +       if (!buf) {
> +               printf("Failed mapping PCAP memory\n");
> +               return -ENOMEM;
> +       }
> +
> +       printf("PCAP capture initialized: addr: 0x%lx max length: %lu\n",
> +              (unsigned long)buf, size);
> +
> +       memcpy(buf, &file_header, sizeof(file_header));
> +       pos = sizeof(file_header);
> +       max_size = size;
> +       initialized = true;
> +       running = false;
> +       buffer_full = false;
> +       incoming_count = 0;
> +       outgoing_count = 0;
> +       return 0;
> +}
> +
> +int pcap_start_stop(bool start)
> +{
> +       if (!initialized) {
> +               printf("error: pcap was not initialized\n");
> +               return -ENODEV;
> +       }
> +
> +       running = start;
> +
> +       return 0;
> +}
> +
> +int pcap_clear(void)
> +{
> +       if (!initialized) {
> +               printf("error: pcap was not initialized\n");
> +               return -ENODEV;
> +       }
> +
> +       pos = sizeof(file_header);
> +       incoming_count = 0;
> +       outgoing_count = 0;
> +       buffer_full = false;
> +
> +       printf("pcap capture cleared\n");
> +       return 0;
> +}
> +
> +int pcap_post(const void *packet, size_t len, bool outgoing)
> +{
> +       struct pcap_packet_header header;
> +       u64 cur_time = timer_get_us();
> +
> +       if (!initialized || !running || !buf)
> +               return -ENODEV;
> +
> +       if (buffer_full)
> +               return -ENOMEM;
> +
> +       if ((pos + len + sizeof(header)) >= max_size) {
> +               buffer_full = true;
> +               printf("\n!!! Buffer is full, consider increasing buffer size !!!\n");
> +               return -ENOMEM;
> +       }
> +
> +       header.ts_sec = cur_time / 1000000;
> +       header.ts_usec = cur_time % 1000000;
> +       header.incl_len = len;
> +       header.orig_len = len;
> +
> +       memcpy(buf + pos, &header, sizeof(header));
> +       pos += sizeof(header);
> +       memcpy(buf + pos, packet, len);
> +       pos += len;
> +
> +       if (outgoing)
> +               outgoing_count++;
> +       else
> +               incoming_count++;
> +
> +       env_set_hex("pcapsize", pos);
> +
> +       return 0;
> +}
> +
> +int pcap_print_status(void)
> +{
> +       if (!initialized) {
> +               printf("pcap was not initialized\n");
> +               return -ENODEV;
> +       }
> +       printf("PCAP status:\n");
> +       printf("\tInitialized addr: 0x%lx\tmax length: %u\n",
> +              (unsigned long)buf, max_size);
> +       printf("\tStatus: %s.\t file size: %u\n", running ? "Active" : "Idle",
> +              pos);
> +       printf("\tIncoming packets: %lu Outgoing packets: %lu\n",
> +              incoming_count, outgoing_count);
> +
> +       return 0;
> +}
> +
> +bool pcap_active(void)
> +{
> +       return running;
> +}
> --
> 2.22.0
>
> _______________________________________________
> U-Boot mailing list
> U-Boot@lists.denx.de
> https://lists.denx.de/listinfo/u-boot
Joe Hershberger Sept. 4, 2019, 4:40 p.m. UTC | #3
Hi Ramon,

https://patchwork.ozlabs.org/patch/1133814/ was applied to http://git.denx.de/?p=u-boot/u-boot-net.git

Thanks!
-Joe

Patch
diff mbox series

diff --git a/cmd/Kconfig b/cmd/Kconfig
index 67284d8a5f..86aa5d8c00 100644
--- a/cmd/Kconfig
+++ b/cmd/Kconfig
@@ -1263,6 +1263,13 @@  config BOOTP_NTPSERVER
 	bool "Request & store 'ntpserverip' from BOOTP/DHCP server"
 	depends on CMD_BOOTP
 
+config CMD_PCAP
+	bool "pcap capture"
+	help
+	  Selecting this will allow capturing all Ethernet packets and store
+	  them in physical memory in a PCAP formated file,
+	  later to be analyzed by PCAP reader application (IE. WireShark).
+
 config BOOTP_PXE
 	bool "Send PXE client arch to BOOTP/DHCP server"
 	default y
diff --git a/cmd/Makefile b/cmd/Makefile
index 0aa3741453..61d5bc885a 100644
--- a/cmd/Makefile
+++ b/cmd/Makefile
@@ -102,6 +102,7 @@  obj-$(CONFIG_CMD_NVEDIT_EFI) += nvedit_efi.o
 obj-$(CONFIG_CMD_ONENAND) += onenand.o
 obj-$(CONFIG_CMD_OSD) += osd.o
 obj-$(CONFIG_CMD_PART) += part.o
+obj-$(CONFIG_CMD_PCAP) += pcap.o
 ifdef CONFIG_PCI
 obj-$(CONFIG_CMD_PCI) += pci.o
 endif
diff --git a/cmd/pcap.c b/cmd/pcap.c
new file mode 100644
index 0000000000..980603f7bd
--- /dev/null
+++ b/cmd/pcap.c
@@ -0,0 +1,71 @@ 
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * (C) Copyright 2019
+ * Ramon Fried <rfried.dev@gmail.com>
+ */
+
+#include <common.h>
+#include <command.h>
+#include <net.h>
+#include <net/pcap.h>
+
+static int do_pcap_init(cmd_tbl_t *cmdtp, int flag, int argc,
+			char * const argv[])
+{
+	phys_addr_t addr;
+	unsigned int size;
+
+	if (argc != 3)
+		return CMD_RET_USAGE;
+
+	addr = simple_strtoul(argv[1], NULL, 16);
+	size = simple_strtoul(argv[2], NULL, 10);
+
+	return pcap_init(addr, size) ? CMD_RET_FAILURE : CMD_RET_SUCCESS;
+}
+
+static int do_pcap_start(cmd_tbl_t *cmdtp, int flag, int argc,
+			 char * const argv[])
+{
+	return pcap_start_stop(true) ? CMD_RET_FAILURE : CMD_RET_SUCCESS;
+}
+
+static int do_pcap_stop(cmd_tbl_t *cmdtp, int flag, int argc,
+			char * const argv[])
+{
+	return pcap_start_stop(false) ? CMD_RET_FAILURE : CMD_RET_SUCCESS;
+}
+
+static int do_pcap_status(cmd_tbl_t *cmdtp, int flag, int argc,
+			  char * const argv[])
+{
+	return pcap_print_status() ? CMD_RET_FAILURE : CMD_RET_SUCCESS;
+}
+
+static int do_pcap_clear(cmd_tbl_t *cmdtp, int flag, int argc,
+			 char * const argv[])
+{
+	return pcap_clear() ? CMD_RET_FAILURE : CMD_RET_SUCCESS;
+}
+
+static char pcap_help_text[] =
+	"- network packet capture\n\n"
+	"pcap\n"
+	"pcap init\t\t\t<addr> <max_size>\n"
+	"pcap start\t\t\tstart capture\n"
+	"pcap stop\t\t\tstop capture\n"
+	"pcap status\t\t\tprint status\n"
+	"pcap clear\t\t\tclear capture buffer\n"
+	"\n"
+	"With:\n"
+	"\t<addr>: user address to which pcap will be stored (hexedcimal)\n"
+	"\t<max_size>: Maximum size of pcap file (decimal)\n"
+	"\n";
+
+U_BOOT_CMD_WITH_SUBCMDS(pcap, "pcap", pcap_help_text,
+			U_BOOT_SUBCMD_MKENT(init, 3, 0, do_pcap_init),
+			U_BOOT_SUBCMD_MKENT(start, 1, 0, do_pcap_start),
+			U_BOOT_SUBCMD_MKENT(stop, 1, 0, do_pcap_stop),
+			U_BOOT_SUBCMD_MKENT(status, 1, 0, do_pcap_status),
+			U_BOOT_SUBCMD_MKENT(clear, 1, 0, do_pcap_clear),
+);
diff --git a/include/net/pcap.h b/include/net/pcap.h
new file mode 100644
index 0000000000..512ba982f1
--- /dev/null
+++ b/include/net/pcap.h
@@ -0,0 +1,55 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright 2019
+ * Ramon Fried <rfried.dev@gmail.com>
+ */
+
+/**
+ * pcap_init() - Initialize PCAP memory buffer
+ *
+ * @paddr	physicaly memory address to store buffer
+ * @size	maximum size of capture file in memory
+ *
+ * @return	0 on success, -ERROR on error
+ */
+int pcap_init(phys_addr_t paddr, unsigned long size);
+
+/**
+ * pcap_start_stop() - start / stop pcap capture
+ *
+ * @start	if true, start capture if false stop capture
+ *
+ * @return	0 on success, -ERROR on error
+ */
+int pcap_start_stop(bool start);
+
+/**
+ * pcap_clear() - clear pcap capture buffer and statistics
+ *
+ * @return	0 on success, -ERROR on error
+ */
+int pcap_clear(void);
+
+/**
+ * pcap_print_status() - print status of pcap capture
+ *
+ * @return	0 on success, -ERROR on error
+ */
+int pcap_print_status(void);
+
+/**
+ * pcap_active() - check if pcap is enabled
+ *
+ * @return	TRUE if active, FALSE if not.
+ */
+bool pcap_active(void);
+
+/**
+ * pcap_post() - Post a packet to PCAP file
+ *
+ * @packet:	packet to post
+ * @len:	packet length in bytes
+ * @outgoing	packet direction (outgoing/incoming)
+ * @return	0 on success, -ERROR on error
+ */
+int pcap_post(const void *packet, size_t len, bool outgoing);
diff --git a/net/Makefile b/net/Makefile
index 6251ff3991..b975badeda 100644
--- a/net/Makefile
+++ b/net/Makefile
@@ -21,6 +21,7 @@  obj-$(CONFIG_CMD_LINK_LOCAL) += link_local.o
 obj-$(CONFIG_NET)      += net.o
 obj-$(CONFIG_CMD_NFS)  += nfs.o
 obj-$(CONFIG_CMD_PING) += ping.o
+obj-$(CONFIG_CMD_PCAP) += pcap.o
 obj-$(CONFIG_CMD_RARP) += rarp.o
 obj-$(CONFIG_CMD_SNTP) += sntp.o
 obj-$(CONFIG_CMD_TFTPBOOT) += tftp.o
diff --git a/net/eth-uclass.c b/net/eth-uclass.c
index 031d558625..4252a02659 100644
--- a/net/eth-uclass.c
+++ b/net/eth-uclass.c
@@ -9,6 +9,9 @@ 
 #include <dm.h>
 #include <environment.h>
 #include <net.h>
+#if defined(CONFIG_CMD_PCAP)
+#include <net/pcap.h>
+#endif
 #include <dm/device-internal.h>
 #include <dm/uclass-internal.h>
 #include "eth_internal.h"
@@ -344,6 +347,10 @@  int eth_send(void *packet, int length)
 		/* We cannot completely return the error at present */
 		debug("%s: send() returned error %d\n", __func__, ret);
 	}
+#if defined(CONFIG_CMD_PCAP)
+	if (ret >= 0)
+		pcap_post(packet, length, true);
+#endif
 	return ret;
 }
 
diff --git a/net/eth_legacy.c b/net/eth_legacy.c
index e250a430f3..0705b7ccea 100644
--- a/net/eth_legacy.c
+++ b/net/eth_legacy.c
@@ -9,6 +9,9 @@ 
 #include <command.h>
 #include <environment.h>
 #include <net.h>
+#if defined(CONFIG_CMD_PCAP)
+#include <net/pcap.h>
+#endif
 #include <phy.h>
 #include <linux/errno.h>
 #include "eth_internal.h"
@@ -352,10 +355,17 @@  int eth_is_active(struct eth_device *dev)
 
 int eth_send(void *packet, int length)
 {
+	int ret;
+
 	if (!eth_current)
 		return -ENODEV;
 
-	return eth_current->send(eth_current, packet, length);
+	ret = eth_current->send(eth_current, packet, length);
+#if defined(CONFIG_CMD_PCAP)
+	if (ret >= 0)
+		pcap_post(packet, lengeth, true);
+#endif
+	return ret;
 }
 
 int eth_rx(void)
diff --git a/net/net.c b/net/net.c
index 58b0417cbe..722fa7a705 100644
--- a/net/net.c
+++ b/net/net.c
@@ -95,6 +95,9 @@ 
 #include <net.h>
 #include <net/fastboot.h>
 #include <net/tftp.h>
+#if defined(CONFIG_CMD_PCAP)
+#include <net/pcap.h>
+#endif
 #if defined(CONFIG_LED_STATUS)
 #include <miiphy.h>
 #include <status_led.h>
@@ -671,6 +674,11 @@  done:
 	net_set_icmp_handler(NULL);
 #endif
 	net_set_state(prev_net_state);
+
+#if defined(CONFIG_CMD_PCAP)
+	if (pcap_active())
+		pcap_print_status();
+#endif
 	return ret;
 }
 
@@ -1083,6 +1091,9 @@  void net_process_received_packet(uchar *in_packet, int len)
 
 	debug_cond(DEBUG_NET_PKT, "packet received\n");
 
+#if defined(CONFIG_CMD_PCAP)
+	pcap_post(in_packet, len, false);
+#endif
 	net_rx_packet = in_packet;
 	net_rx_packet_len = len;
 	et = (struct ethernet_hdr *)in_packet;
diff --git a/net/pcap.c b/net/pcap.c
new file mode 100644
index 0000000000..4036d8a3fa
--- /dev/null
+++ b/net/pcap.c
@@ -0,0 +1,156 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2019 Ramon Fried <rfried.dev@gmail.com>
+ */
+
+#include <common.h>
+#include <net.h>
+#include <net/pcap.h>
+#include <time.h>
+#include <asm/io.h>
+
+#define LINKTYPE_ETHERNET	1
+
+static bool initialized;
+static bool running;
+static bool buffer_full;
+static void *buf;
+static unsigned int max_size;
+static unsigned int pos;
+
+static unsigned long incoming_count;
+static unsigned long outgoing_count;
+
+struct pcap_header {
+	u32 magic;
+	u16 version_major;
+	u16 version_minor;
+	s32 thiszone;
+	u32 sigfigs;
+	u32 snaplen;
+	u32 network;
+};
+
+struct pcap_packet_header {
+	u32 ts_sec;
+	u32 ts_usec;
+	u32 incl_len;
+	u32 orig_len;
+};
+
+static struct pcap_header file_header = {
+	.magic = 0xa1b2c3d4,
+	.version_major = 2,
+	.version_minor = 4,
+	.snaplen = 65535,
+	.network = LINKTYPE_ETHERNET,
+};
+
+int pcap_init(phys_addr_t paddr, unsigned long size)
+{
+	buf = map_physmem(paddr, size, 0);
+	if (!buf) {
+		printf("Failed mapping PCAP memory\n");
+		return -ENOMEM;
+	}
+
+	printf("PCAP capture initialized: addr: 0x%lx max length: %lu\n",
+	       (unsigned long)buf, size);
+
+	memcpy(buf, &file_header, sizeof(file_header));
+	pos = sizeof(file_header);
+	max_size = size;
+	initialized = true;
+	running = false;
+	buffer_full = false;
+	incoming_count = 0;
+	outgoing_count = 0;
+	return 0;
+}
+
+int pcap_start_stop(bool start)
+{
+	if (!initialized) {
+		printf("error: pcap was not initialized\n");
+		return -ENODEV;
+	}
+
+	running = start;
+
+	return 0;
+}
+
+int pcap_clear(void)
+{
+	if (!initialized) {
+		printf("error: pcap was not initialized\n");
+		return -ENODEV;
+	}
+
+	pos = sizeof(file_header);
+	incoming_count = 0;
+	outgoing_count = 0;
+	buffer_full = false;
+
+	printf("pcap capture cleared\n");
+	return 0;
+}
+
+int pcap_post(const void *packet, size_t len, bool outgoing)
+{
+	struct pcap_packet_header header;
+	u64 cur_time = timer_get_us();
+
+	if (!initialized || !running || !buf)
+		return -ENODEV;
+
+	if (buffer_full)
+		return -ENOMEM;
+
+	if ((pos + len + sizeof(header)) >= max_size) {
+		buffer_full = true;
+		printf("\n!!! Buffer is full, consider increasing buffer size !!!\n");
+		return -ENOMEM;
+	}
+
+	header.ts_sec = cur_time / 1000000;
+	header.ts_usec = cur_time % 1000000;
+	header.incl_len = len;
+	header.orig_len = len;
+
+	memcpy(buf + pos, &header, sizeof(header));
+	pos += sizeof(header);
+	memcpy(buf + pos, packet, len);
+	pos += len;
+
+	if (outgoing)
+		outgoing_count++;
+	else
+		incoming_count++;
+
+	env_set_hex("pcapsize", pos);
+
+	return 0;
+}
+
+int pcap_print_status(void)
+{
+	if (!initialized) {
+		printf("pcap was not initialized\n");
+		return -ENODEV;
+	}
+	printf("PCAP status:\n");
+	printf("\tInitialized addr: 0x%lx\tmax length: %u\n",
+	       (unsigned long)buf, max_size);
+	printf("\tStatus: %s.\t file size: %u\n", running ? "Active" : "Idle",
+	       pos);
+	printf("\tIncoming packets: %lu Outgoing packets: %lu\n",
+	       incoming_count, outgoing_count);
+
+	return 0;
+}
+
+bool pcap_active(void)
+{
+	return running;
+}