How to use arbitrary "sg_raw " argument in golang? - go

I am trying to replicate sg_inq through sg_raw
This is the command used:
inq_cmd := exec.Command("sg_raw", "-r", "512", "/dev/sg0", "12 00 00 00 60 00")
stdoutStderr, err := read_cmd.CombinedOutput()
if err != nil {
log.Fatal(err)
}
fmt.Printf("%s\n", stdoutStderr)
Output after execution is
Inq COMMAND :
exit status 1
Invalid command byte '12 00 00 00 60 00'
Inquire COMMAND :
2020/05/28 19:42:48 exit status 1
exit status 1
Invalid command byte '12 00 00 00 60 00'
Usage: sg_raw [OPTION]* DEVICE CDB0 CDB1 ...
Options:
-b, --binary Dump data in binary form, even when writing to stdout
-h, --help Show this message and exit
-i, --infile=IFILE Read data to send from IFILE (default: stdin)
-k, --skip=LEN Skip the first LEN bytes when reading data to send
-n, --nosense Don't display sense information
-o, --outfile=OFILE Write binary data to OFILE (def: hexdump to stdout)
-r, --request=RLEN Request up to RLEN bytes of data (data-in)
-R, --readonly Open DEVICE read-only (default: read-write)
-s, --send=SLEN Send SLEN bytes of data (data-out)
-t, --timeout=SEC Timeout in seconds (default: 20)
-v, --verbose Increase verbosity
-V, --version Show version information and exit
Between 6 and 256 command bytes (two hex digits each) can be specified
and will be sent to DEVICE. Lengths RLEN and SLEN are decimal by
default. Bidirectional commands accepted.
Simple example: Perform INQUIRY on /dev/sg0:
sg_raw -r 1k /dev/sg0 12 00 00 00 60 00
What's wrong in the command? It would be a great help! Thanks in advance!

Related

QEMU gdb does not show instructions of firmware

I am trying to debug the bios.bin that comes with the QEMU emulator. I am starting QEMU as follows:
qemu-system-x86_64 -bios bios.bin -s -S
I then start start debugging with:
gdb
target remote localhost:1234
GDB is at the Intel handoff state 0xfffffff0 where now the firmware/BIOS should be. However there is nothing at this location in memory. Even if step through a more instructions via nexti it decodes as all zeros.
What am I doing wrong or am I misunderstanding something? I basically want to get the first instruction the cpu calls and continue debugging from there.
QEMU isn't the problem here, but GDB is. I will start with a recommendations if you intend to use GDB to debug the BIOS:
Do not use qemu-system-x86_64. Use qemu-system-i386 instead. This will avoid a packet too long problem and a pile of numbers being displayed. This may or may not happen to you depending on the version of GDB being used.
With that being said, GDB's real problem is that it has no knowledge of real mode segment:offset addressing. When you boot QEMU it starts in 16-bit real mode to start executing the legacy BIOS. GDB's lack of real mode debugging support is the real issue. You can read more about it in another Stackoverflow answer I wrote. To summarize:
Unfortunately by default gdb doesn't do segment:offset calculations
and will use the value in EIP for breakpoints. You have to specify
breakpoints as 32-bit addresses (EIP).
When it comes to stepping through real mode code it can be cumbersome
because gdb doesn't handle real mode segmentation. If you step into an
interrupt handler you'll discover gdb will display the assembly code
relative to EIP. Effectively gdb will be showing you disassembly of
the wrong memory location since it didn't account for CS.
Over the years changes to GDB have made debugging real mode code more involved and negotiating connections to remote hosts has become more problematic. Based on my answer above and the other 2 answers under the same question you may be able to get this working satisfactorily on old and new versions of GDB by trying the following:
Make a file called target.xml with the following:
<?xml version="1.0"?><!DOCTYPE target SYSTEM "gdb-target.dtd">
<target>
<architecture>i8086</architecture>
<xi:include href="i386-32bit.xml"/>
</target>
Create a file called i386-32bit.xml with the contents of this URL. Alternatively you can retrieve this file from the command line on Linux based OSes with:
wget https://raw.githubusercontent.com/qemu/qemu/master/gdb-xml/i386-32bit.xml
Create a script file called gdb_init_real_mode.txt with the following:
# Special mode for GDB that allows to debug/disassemble REAL MODE x86 code
#
# It has been designed to be used with QEMU or BOCHS gdb-stub
#
# 08/2011 Hugo Mercier - GPL v3 license
#
# Freely inspired from "A user-friendly gdb configuration file" widely available
# on the Internet
set confirm off
set verbose off
set prompt \033[31mreal-mode-gdb$ \033[0m
set output-radix 0d10
set input-radix 0d10
# These make gdb never pause in its output
set height 0
set width 0
# Intel syntax
set disassembly-flavor intel
# Real mode
#set architecture i8086
set $SHOW_CONTEXT = 1
set $REAL_MODE = 1
# By default A20 is present
set $ADDRESS_MASK = 0x1FFFFF
# nb of instructions to display
set $CODE_SIZE = 10
define enable-a20
set $ADDRESS_MASK = 0x1FFFFF
end
define disable-a20
set $ADDRESS_MASK = 0x0FFFFF
end
# convert segment:offset address to physical address
define r2p
if $argc < 2
printf "Arguments: segment offset\n"
else
set $ADDR = (((unsigned long)$arg0 & 0xFFFF) << 4) + (((unsigned long)$arg1 & 0xFFFF) & $ADDRESS_MASK)
printf "0x%05X\n", $ADDR
end
end
document r2p
Convert segment:offset address to physical address
Set the global variable $ADDR to the computed one
end
# get address of Interruption
define int_addr
if $argc < 1
printf "Argument: interruption_number\n"
else
set $offset = (unsigned short)*($arg0 * 4)
set $segment = (unsigned short)*($arg0 * 4 + 2)
r2p $segment $offset
printf "%04X:%04X\n", $segment, $offset
end
end
document int_addr
Get address of interruption
end
define compute_regs
set $rax = ((unsigned long)$eax & 0xFFFF)
set $rbx = ((unsigned long)$ebx & 0xFFFF)
set $rcx = ((unsigned long)$ecx & 0xFFFF)
set $rdx = ((unsigned long)$edx & 0xFFFF)
set $rsi = ((unsigned long)$esi & 0xFFFF)
set $rdi = ((unsigned long)$edi & 0xFFFF)
set $rbp = ((unsigned long)$ebp & 0xFFFF)
set $rsp = ((unsigned long)$esp & 0xFFFF)
set $rcs = ((unsigned long)$cs & 0xFFFF)
set $rds = ((unsigned long)$ds & 0xFFFF)
set $res = ((unsigned long)$es & 0xFFFF)
set $rss = ((unsigned long)$ss & 0xFFFF)
set $rip = ((((unsigned long)$cs & 0xFFFF) << 4) + ((unsigned long)$eip & 0xFFFF)) & $ADDRESS_MASK
set $r_ss_sp = ((((unsigned long)$ss & 0xFFFF) << 4) + ((unsigned long)$esp & 0xFFFF)) & $ADDRESS_MASK
set $r_ss_bp = ((((unsigned long)$ss & 0xFFFF) << 4) + ((unsigned long)$ebp & 0xFFFF)) & $ADDRESS_MASK
end
define print_regs
printf "AX: %04X BX: %04X ", $rax, $rbx
printf "CX: %04X DX: %04X\n", $rcx, $rdx
printf "SI: %04X DI: %04X ", $rsi, $rdi
printf "SP: %04X BP: %04X\n", $rsp, $rbp
printf "CS: %04X DS: %04X ", $rcs, $rds
printf "ES: %04X SS: %04X\n", $res, $rss
printf "\n"
printf "IP: %04X EIP:%08X\n", ((unsigned short)$eip & 0xFFFF), $eip
printf "CS:IP: %04X:%04X (0x%05X)\n", $rcs, ((unsigned short)$eip & 0xFFFF), $rip
printf "SS:SP: %04X:%04X (0x%05X)\n", $rss, $rsp, $r_ss_sp
printf "SS:BP: %04X:%04X (0x%05X)\n", $rss, $rbp, $r_ss_bp
end
document print_regs
Print CPU registers
end
define print_eflags
printf "OF <%d> DF <%d> IF <%d> TF <%d>",\
(($eflags >> 0xB) & 1), (($eflags >> 0xA) & 1), \
(($eflags >> 9) & 1), (($eflags >> 8) & 1)
printf " SF <%d> ZF <%d> AF <%d> PF <%d> CF <%d>\n",\
(($eflags >> 7) & 1), (($eflags >> 6) & 1),\
(($eflags >> 4) & 1), (($eflags >> 2) & 1), ($eflags & 1)
printf "ID <%d> VIP <%d> VIF <%d> AC <%d>",\
(($eflags >> 0x15) & 1), (($eflags >> 0x14) & 1), \
(($eflags >> 0x13) & 1), (($eflags >> 0x12) & 1)
printf " VM <%d> RF <%d> NT <%d> IOPL <%d>\n",\
(($eflags >> 0x11) & 1), (($eflags >> 0x10) & 1),\
(($eflags >> 0xE) & 1), (($eflags >> 0xC) & 3)
end
document print_eflags
Print eflags register.
end
# dump content of bytes in memory
# arg0 : addr
# arg1 : nb of bytes
define _dump_memb
if $argc < 2
printf "Arguments: address number_of_bytes\n"
else
set $_nb = $arg1
set $_i = 0
set $_addr = $arg0
while ($_i < $_nb)
printf "%02X ", *((unsigned char*)$_addr + $_i)
set $_i++
end
end
end
# dump content of memory in words
# arg0 : addr
# arg1 : nb of words
define _dump_memw
if $argc < 2
printf "Arguments: address number_of_words\n"
else
set $_nb = $arg1
set $_i = 0
set $_addr = $arg0
while ($_i < $_nb)
printf "%04X ", *((unsigned short*)$_addr + $_i)
set $_i++
end
end
end
# display data at given address
define print_data
if ($argc > 0)
set $seg = $arg0
set $off = $arg1
set $raddr = ($arg0 << 16) + $arg1
set $maddr = ($arg0 << 4) + $arg1
set $w = 16
set $i = (int)0
while ($i < 4)
printf "%08X: ", ($raddr + $i * $w)
set $j = (int)0
while ($j < $w)
printf "%02X ", *(unsigned char*)($maddr + $i * $w + $j)
set $j++
end
printf " "
set $j = (int)0
while ($j < $w)
set $c = *(unsigned char*)($maddr + $i * $w + $j)
if ($c > 32) && ($c < 128)
printf "%c", $c
else
printf "."
end
set $j++
end
printf "\n"
set $i++
end
end
end
define context
printf "---------------------------[ STACK ]---\n"
_dump_memw $r_ss_sp 8
printf "\n"
set $_a = $r_ss_sp + 16
_dump_memw $_a 8
printf "\n"
printf "---------------------------[ DS:SI ]---\n"
print_data $ds $rsi
printf "---------------------------[ ES:DI ]---\n"
print_data $es $rdi
printf "----------------------------[ CPU ]----\n"
print_regs
print_eflags
printf "---------------------------[ CODE ]----\n"
set $_code_size = $CODE_SIZE
# disassemble
# first call x/i with an address
# subsequent calls to x/i will increment address
if ($_code_size > 0)
x /i $rip
set $_code_size--
end
while ($_code_size > 0)
x /i
set $_code_size--
end
end
document context
Print context window, i.e. regs, stack, ds:esi and disassemble cs:eip.
end
define hook-stop
compute_regs
if ($SHOW_CONTEXT > 0)
context
end
end
document hook-stop
!!! FOR INTERNAL USE ONLY - DO NOT CALL !!!
end
# add a breakpoint on an interrupt
define break_int
set $offset = (unsigned short)*($arg0 * 4)
set $segment = (unsigned short)*($arg0 * 4 + 2)
break *$offset
end
define break_int_if_ah
if ($argc < 2)
printf "Arguments: INT_N AH\n"
else
set $addr = (unsigned short)*($arg0 * 4)
set $segment = (unsigned short)*($arg0 * 4 + 2)
break *$addr if ((unsigned long)$eax & 0xFF00) == ($arg1 << 8)
end
end
document break_int_if_ah
Install a breakpoint on INT N only if AH is equal to the expected value
end
define break_int_if_ax
if ($argc < 2)
printf "Arguments: INT_N AX\n"
else
set $addr = (unsigned short)*($arg0 * 4)
set $segment = (unsigned short)*($arg0 * 4 + 2)
break *$addr if ((unsigned long)$eax & 0xFFFF) == $arg1
end
end
document break_int_if_ax
Install a breakpoint on INT N only if AX is equal to the expected value
end
define stepo
## we know that an opcode starting by 0xE8 has a fixed length
## for the 0xFF opcodes, we can enumerate what is possible to have
set $lip = $rip
set $offset = 0
# first, get rid of segment prefixes, if any
set $_byte1 = *(unsigned char *)$rip
# CALL DS:xx CS:xx, etc.
if ($_byte1 == 0x3E || $_byte1 == 0x26 || $_byte1 == 0x2E || $_byte1 == 0x36 || $_byte1 == 0x3E || $_byte1 == 0x64 || $_byte1 == 0x65)
set $lip = $rip + 1
set $_byte1 = *(unsigned char*)$lip
set $offset = 1
end
set $_byte2 = *(unsigned char *)($lip+1)
set $_byte3 = *(unsigned char *)($lip+2)
set $noffset = 0
if ($_byte1 == 0xE8)
# call near
set $noffset = 3
else
if ($_byte1 == 0xFF)
# A "ModR/M" byte follows
set $_mod = ($_byte2 & 0xC0) >> 6
set $_reg = ($_byte2 & 0x38) >> 3
set $_rm = ($_byte2 & 7)
#printf "mod: %d reg: %d rm: %d\n", $_mod, $_reg, $_rm
# only for CALL instructions
if ($_reg == 2 || $_reg == 3)
# default offset
set $noffset = 2
if ($_mod == 0)
if ($_rm == 6)
# a 16bit address follows
set $noffset = 4
end
else
if ($_mod == 1)
# a 8bit displacement follows
set $noffset = 3
else
if ($_mod == 2)
# 16bit displacement
set $noffset = 4
end
end
end
end
# end of _reg == 2 or _reg == 3
else
# else byte1 != 0xff
if ($_byte1 == 0x9A)
# call far
set $noffset = 5
else
if ($_byte1 == 0xCD)
# INTERRUPT CASE
set $noffset = 2
end
end
end
# end of byte1 == 0xff
end
# else byte1 != 0xe8
# if we have found a call to bypass we set a temporary breakpoint on next instruction and continue
if ($noffset != 0)
set $_nextaddress = $eip + $offset + $noffset
printf "Setting BP to %04X\n", $_nextaddress
tbreak *$_nextaddress
continue
# else we just single step
else
nexti
end
end
document stepo
Step over calls
This function will set a temporary breakpoint on next instruction after the call so the call will be bypassed
You can safely use it instead nexti since it will single step code if it's not a call instruction (unless you want to go into the call function)
end
define step_until_iret
set $SHOW_CONTEXT=0
set $_found = 0
while (!$_found)
if (*(unsigned char*)$rip == 0xCF)
set $_found = 1
else
stepo
end
end
set $SHOW_CONTEXT=1
context
end
define step_until_ret
set $SHOW_CONTEXT=0
set $_found = 0
while (!$_found)
set $_p = *(unsigned char*)$rip
if ($_p == 0xC3 || $_p == 0xCB || $_p == 0xC2 || $_p == 0xCA)
set $_found = 1
else
stepo
end
end
set $SHOW_CONTEXT=1
context
end
define step_until_int
set $SHOW_CONTEXT = 0
while (*(unsigned char*)$rip != 0xCD)
stepo
end
set $SHOW_CONTEXT = 1
context
end
# Find a pattern in memory
# The pattern is given by a string as arg0
# If another argument is present it gives the starting address (0 otherwise)
define find_in_mem
if ($argc >= 2)
set $_addr = $arg1
else
set $_addr = 0
end
set $_found = 0
set $_tofind = $arg0
while ($_addr < $ADDRESS_MASK) && (!$_found)
if ($_addr % 0x100 == 0)
printf "%08X\n", $_addr
end
set $_i = 0
set $_found = 1
while ($_tofind[$_i] != 0 && $_found == 1)
set $_b = *((char*)$_addr + $_i)
set $_t = (char)$_tofind[$_i]
if ($_t != $_b)
set $_found = 0
end
set $_i++
end
if ($_found == 1)
printf "Code found at 0x%05X\n", $_addr
end
set $_addr++
end
end
document find_in_mem
Find a pattern in memory
The pattern is given by a string as arg0
If another argument is present it gives the starting address (0 otherwise)
end
define step_until_code
set $_tofind = $arg0
set $SHOW_CONTEXT = 0
set $_found = 0
while (!$_found)
set $_i = 0
set $_found = 1
while ($_tofind[$_i] != 0 && $_found == 1)
set $_b = *((char*)$rip + $_i)
set $_t = (char)$_tofind[$_i]
if ($_t != $_b)
set $_found = 0
end
set $_i++
end
if ($_found == 0)
stepo
end
end
set $SHOW_CONTEXT = 1
context
end
This script provides features that allow a person to better debug real mode code. It will display the values of the segments and the registers and will attempt to resolve segment:offset addresses by properly computing a physical address to decode instructions from.
Once you have the 3 files above you can attempt to debug the BIOS this way:
qemu-system-i386 -bios bios.bin -s -S &
gdb -ix gdb_init_real_mode.txt \
-ex 'set tdesc filename target.xml' \
-ex 'target remote localhost:1234'
There are a number of additional commands added mentioned in my related answer linked to earlier. This script takes care of setting the architecture to i8086 and then hooks itself into gdb. It provides a number of new macros that can make stepping through 16 bit code easier:
break_int : adds a breakpoint on a software interrupt vector (the way
the good old MS DOS and BIOS expose their APIs)
break_int_if_ah : adds a conditional breakpoint on a software
interrupt. AH has to be equals to the given parameter. This is used to
filter service calls of interrupts. For instance, you sometimes only
wants to break when the function AH=0h of the interruption 10h is
called (change screen mode).
stepo : this is a kabalistic macro used to 'step-over' function and
interrupt calls. How does it work ? The opcode of the current
instruction is extracted and if it is a function or interrupt call,
the "next" instruction address is computed, a temporary breakpoint is
added on that address and the 'continue' function is called.
step_until_ret : this is used to singlestep until we encounter a 'RET'
instruction.
step_until_iret : this is used to singlestep until we encounter an
'IRET' instruction.
step_until_int : this is used to singlestep until we encounter an
'INT' instruction.
If you use the command above to launch QEMU you should see something like:
---------------------------[ STACK ]---
0000 0000 0000 0000 0000 0000 0000 0000
0000 0000 0000 0000 0000 0000 0000 0000
---------------------------[ DS:SI ]---
00000000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00000010: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00000020: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00000030: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
---------------------------[ ES:DI ]---
00000000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00000010: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00000020: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00000030: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
----------------------------[ CPU ]----
AX: 0000 BX: 0000 CX: 0000 DX: 0663
SI: 0000 DI: 0000 SP: 0000 BP: 0000
CS: F000 DS: 0000 ES: 0000 SS: 0000
IP: FFF0 EIP:0000FFF0
CS:IP: F000:FFF0 (0xFFFF0)
SS:SP: 0000:0000 (0x00000)
SS:BP: 0000:0000 (0x00000)
OF <0> DF <0> IF <0> TF <0> SF <0> ZF <0> AF <0> PF <0> CF <0>
ID <0> VIP <0> VIF <0> AC <0> VM <0> RF <0> NT <0> IOPL <0>
---------------------------[ CODE ]----
0xffff0: jmp 0xf000:0xe05b
0xffff5: xor BYTE PTR ds:0x322f,dh
0xffff9: xor bp,WORD PTR [bx]
0xffffb: cmp WORD PTR [bx+di],di
0xffffd: add ah,bh
0xfffff: add BYTE PTR [bx+si],al
0x100001: add BYTE PTR [bx+si],al
0x100003: add BYTE PTR [bx+si],al
0x100005: add BYTE PTR [bx+si],al
0x100007: add BYTE PTR [bx+si],al
0x0000fff0 in ?? ()
real-mode-gdb$
As you can see it prints out part of the data at the top of the stack, some memory regions common to real mode programs, the segment registers and the regular registers. The instructions have been properly decoded from the right place in memory. You should see the program starting to execute at 0xffff0. Some BIOSes might have a different first instruction but one of the first few instructions will be a FAR JMP to another place in the BIOS:
0xffff0: jmp 0xf000:0xe05b

How to solve this message "repetition-operator operand invalid" of grep?

I'm trying to extract texts by using grep on mac
used regex is like this
$grep -E '.+output:([\S\s](?!DEBUG))*?123456789[\S\s]*?END\]' ./AppLog.txt
"123456789" is search id.
then execute this regex,
terminal says "grep: repetition-operator operand invalid."
but In sublime text editor, it executes correctly.
How to fix this error of terminal on mac?
search text example)
I'd like to capture from "output" line to "END" line by UserID.
DEBUG|2018-03-27,14:41:43.089|blabla~~|output:
[START]
=========================================================
00 G_messageText = {"success"}
01 NEW_CS_YN = {"N"}
02 G_messageID = {"0006"}
03 sTaxYn = {"0"}
04 ErrorMsg = {"SUCC"}
05 ErrorCode = {"0"}
06 UserNum = {"111111111"}
07 UserID = {"123456789"} <= search id
08 G_messageTitle = {"notice"}
09 G_messageSeverity = {"2"}
===============================================
[ END ]
DEBUG|2018-03-27,14:41:43.089|blabla~~~
I solved this problem by using "pcregrep".
you can install this program by typing 'brew install pcre'.
thanks.

Error while giving more command related to ipv6table

I am facing issue while giving command
ip6tables -A DDoS -j DROP
It is resulting in errors like
root#TimeProvider:~# ip6tables -A DDoS -j DROP
ip6tables: Invalid argument.
Run `dmesg' for more information.
root#TimeProvider:~# dmesg|tail -n 20 ip6_tables: limit match: invalid size 40 != 48
ip6_tables: limit match: invalid size 40 != 48
ip6_tables: limit match: invalid size 40 != 48
ip6_tables: limit match: invalid size 40 != 48
ip6_tables: limit match: invalid size 40 != 48
ip6_tables: limit match: invalid size 40 != 48
ip6_tables: limit match: invalid size 40 != 48
ip6_tables: limit match: invalid size 40 != 48
ip6_tables: limit match: invalid size 40 != 48
ADDRCONF(NETDEV_UP):
mgmt0: link is not ready
mgmt0: Link is up - 1000/Full
ADDRCONF(NETDEV_CHANGE):
mgmt0: link becomes ready TMAC switching to SyncE slave mode on PHY 0 TMAC switching to SyncE master mode on PHY 1
mgmt0: no IPv6 routers present TMAC switching to SyncE slave mode on PHY 0 TMAC switching to SyncE master mode on PHY 1
eth0: no IPv6 routers present
eth1: no IPv6 routers present
ip6_tables: limit match: invalid size 40 != 48
Is it a syntax error of the command or is it a system error?

how to properly read from stream in bash

I am reading from the shared memory a stream producing an infinite information output such as:
0x1 (TimeStamp) 12Bytes:11216 + 1771/(47999+1) (0.036896) delta= 0+ 1536/(47999+1) (0.032000) 11216.013361 23.534ms 2015.06.25 11:51:16.525
0x4 (ReferenceTime) 12Bytes:11215 + 24786286/(26999999+1) (0.918011) delta= 0+ 806359/(26999999+1) (0.029856) 11216.013376 -95.366ms 2015.06.25 11:51:16.525
0x6 (ProcessDelay) 4Bytes: 32 (0x20)
0x7 (ClockAccuracy) 8Bytes: offset=0.000ppm (+-0.000ppm)
0xb (ClockId) 8Bytes: 01 00 00 00 42 22 01 00
0x20001 (SampleRate) 4Bytes: 48000 (0xbb80)
0x20002 (Channels) 4Bytes: 6 (0x6)
0x20003 (PcmLevel) 24Bytes: -11041 -11541 -49076 -86121 -24846 -24382
0x20004 (PcmPeak) 24Bytes: -8088 -8697 -37244 -84288 -21437 -21769
0x2000e (DolbyDpMetadata) 39352Bytes:
Linear Time: 11216 + 1771/(47999+1) (0.036896) delta= 0+ 1536/(47999+1) (0.032000)
if i try to read the stream with the following command:
while read line;
do
echo "$line";
echo "im here!"
done < <(../tools/spucat adec-68)
wherespucat is a cpp binary exacutable that continuosly print out on console using printf() information about incoming data packets.
this is the result:
im here!
�k�G��E�x����b��h�������c����2��/n��-�U���QE�L�x���c�������������������������������x��4����O��M�����/��(������������������~��E�*�������;
im here!
������r��$�|��J�n�P�4�
if i start the script whit this command:
while read line;
do
echo "$line";
echo "im here!"
done < $(../tools/spucat adec-68)
it actually never go inside the while loop, just start to print out the stream whaiting for the end.
Is tehere a way to read it line by line and process it inside the while loop?
spucat is dumping to the standard error (no idea why), so to processing it must be redirect to the standard output:
while read -r line;
do
echo "$line";
echo "im here!"
done < <(../tools/spucat -p 4 adec-68 2>&1 > /dev/null)

Expect script to simulate SNMP

I want to monitor a device that doesn´t support SNMP, so I have tried get a counter via an expect script. This script connects to the device using SSH, logs the output on a file and then it parses the output in order to get the desired counter.
When I execute the script from the console I get the following desired output:
root#box:/path# ./GGSN-PDP-Contexts.expect
.1.3.6.1.4.1.6147.2.1
Integer32
310838
However, when I try to get the result using snmpget it doesn´t work!
root#box:/path# snmpget -m TDP-MIB -v 2c -c TM_Com_Pub localhost .1.3.6.1.4.1.6147.2.1
TDP-MIB::PDPContextsNumber = No Such Instance currently exists at this OID
By the way, this is the relevant configuration at snmpd.conf:
pass .1.3.6.1.4.1.6147.2.1 /usr/bin/expect /path/GGSN-PDP-Contexts.expect
And this is the expect script that I'm using:
#!/usr/bin/expect -f
# Constants
set user "user"
set device "10.10.222.176"
set pass "blablabla"
set timeout -1
set prompt "GGSN-LV02#"
set file "./GGSN-PDP-Contexts.log"
# Options
match_max 100000
log_user 0
# Access to device
spawn ssh -oStrictHostKeyChecking=no -oCheckHostIP=no $user#$device
expect "*?assword:*"
send -- "$pass\r"
# Commands execution
expect -exact "$prompt"
send -- "display pdp-number\r"
log_file -a $file
# Logging
expect -exact "$prompt"
log_file
send -- "quit\r"
# Get the value
set result [exec cat $file | grep "ALL GTP" | cut -d " " -f14]
set value [format %d $result]
# Print the value
puts ".1.3.6.1.4.1.6147.2.1"
puts "Integer32"
puts $value # If I replace the $value with a number, it doesn't work either
# Erase log file
exec rm $file
close
Could you bring me any hint? Thanks in advance!
EDIT:
In addition, these are the last lines of snmpget's debug output:
trace: snmp_comstr_parse(): snmp_auth.c, 135:
dumph_recv: SNMP version
dumpx_recv: 02 01 01
dumpv_recv: Integer: 1 (0x01)
trace: snmp_comstr_parse(): snmp_auth.c, 147:
dumph_recv: community string
dumpx_recv: 04 0A 54 4D 5F 43 6F 6D 5F 50 75 62
dumpv_recv: String: TM_Com_Pub
trace: _snmp_parse(): snmp_api.c, 4149:
dumph_recv: PDU
trace: snmp_pdu_parse(): snmp_api.c, 4255:
dumpv_recv: Command RESPONSE
trace: snmp_pdu_parse(): snmp_api.c, 4336:
dumph_recv: request_id
dumpx_recv: 02 04 3B 9E CF 74
dumpv_recv: Integer: 1000263540 (0x3B9ECF74)
trace: snmp_pdu_parse(): snmp_api.c, 4347:
dumph_recv: error status
dumpx_recv: 02 01 00
dumpv_recv: Integer: 0 (0x00)
trace: snmp_pdu_parse(): snmp_api.c, 4358:
dumph_recv: error index
dumpx_recv: 02 01 00
dumpv_recv: Integer: 0 (0x00)
trace: snmp_pdu_parse(): snmp_api.c, 4376:
dumph_recv: VarBindList
trace: snmp_pdu_parse(): snmp_api.c, 4406:
dumph_recv: VarBind
trace: snmp_parse_var_op(): snmp.c, 166:
dumph_recv: Name
dumpx_recv: 06 09 2B 06 01 04 01 B0 03 02 01
dumpv_recv: ObjID: TDP-MIB::PDPContextsNumber
trace: snmp_pdu_parse(): snmp_api.c, 4415:
dumph_recv: Value
TDP-MIB::PDPContextsNumber = No Such Instance currently exists at this OID
Also, this is my current MIB:
TDP-MIB DEFINITIONS ::= BEGIN
IMPORTS
MODULE-IDENTITY, OBJECT-TYPE, Integer32, enterprises
FROM SNMPv2-SMI
OBJECT-GROUP FROM SNMPv2-CONF;
TDP MODULE-IDENTITY
LAST-UPDATED "201210080000Z" -- 8/oct/2012
ORGANIZATION "TELEFONICA"
CONTACT-INFO "Authors: Hernan Romano / Antonio Ocampo
Email: h.romanoc#pucp.edu.pe / aocampo#pucp.edu.pe"
DESCRIPTION "MIB para gestionar los equipos que carecen de SNMP"
REVISION "201210080000Z" -- 08/oct/2012
DESCRIPTION "Revision 2.1"
::= { enterprises 6147 }
Nokia OBJECT IDENTIFIER ::= { TDP 1 }
Huawei OBJECT IDENTIFIER ::= { TDP 2 }
TDPMIBConformance OBJECT IDENTIFIER ::= { TDP 3 }
ClearCodeGroup1 OBJECT-TYPE
SYNTAX Integer32
MAX-ACCESS read-only
STATUS current
DESCRIPTION "Clear Code Group 1"
::= { Nokia 1 }
PDPContextsNumber OBJECT-TYPE
SYNTAX Integer32
MAX-ACCESS read-only
STATUS current
DESCRIPTION "PDP Contexts Number"
::= { Huawei 1 }
TDPMIBGroup OBJECT IDENTIFIER
::= { TDPMIBConformance 1 }
--grupoTDP OBJECT-GROUP
-- OBJECTS {
-- ClearCodeGroup1,
-- PDPContextsNumber
-- }
-- STATUS current
-- DESCRIPTION "Objetos para el monitoreo de los equipos que carecen de SNMP"
-- ::= { TDPMIBGroup 1 }
END
Finally solved :) The trouble was the path file.
Instead of relative path:
set file "./GGSN-PDP-Contexts.log"
I put the absolute path:
set file "/FULL_PATH/GGSN-PDP-Contexts.log"
and snmpget works!!
root#box:/path# snmpget -m TDP-MIB -v 2c -c TM_Com_Pub localhost .1.3.6.1.4.1.6147.2.1
TDP-MIB::PDPContextsNumber = INTEGER: 319291

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