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

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; +}