[sr-dev] kamailio 3.1.0 crash on ssl-dos attack
Jijo
realjijo at gmail.com
Sat Dec 10 00:53:31 CET 2011
Hi
Since TLS run on TCP, the max TLS connections accepted is based on
tcp_max_connections. I thought its better to limit the max tls
connections, since tls require more memory for each tls connection.
I did look futher into the issue and the kamailio crashes only when the
tool(*thc-ssl-dos)* is ran with periodic renegotiation. Kamailo doesn't
crash if the renegotiation is disabled in the tool.
The htppd has fixed this issue by providing a flag to disable TLS
renegotation in the server from any client. Please find the httpd patch at
http://mail-archives.apache.org/mod_mbox/httpd-dev/200911.mbox/raw/%3c20091106030922.GA3764@redhat.com%3e/
So I was thinking to apply the same patch in kamailio also. We could have a
new flag in tls_domain structure to enable or disable renegotation.
Please have a look and let me know your findings.
Thanks
Jijo
On Fri, Dec 9, 2011 at 1:53 AM, Daniel-Constantin Mierla
<miconda at gmail.com>wrote:
> Hello,
>
> my plan is to look at it as I get back to office (being few days off).
>
> But, isn't tcp_max_connections applied to tls connections? If not, adding
> such limit will be good anyhow.
>
> Cheers,
> Daniel
>
>
>
> On 12/7/11 8:57 PM, Jijo wrote:
>
> Hi All..
>
> Any comments/suggestions on this issue?
>
> Thanks
> Jijo
>
> On Mon, Dec 5, 2011 at 6:56 PM, Jijo <realjijo at gmail.com> wrote:
>
>> Hello
>>
>> I tested using 3.2 and i got the same error. I couldn't get the memlog,
>> when i enable , the system doesn't come up.
>>
>> The latest update from http://www.thc.org/thc-ssl-dos/ says that
>>
>> "2011-OCT-24 UPDATE:
>> SSL-DOS released. Some organizations already found out about this release
>> a while ago and mistakenly identified it as an SSL-RENEGOTIATION BUG. This
>> is not true. The tool can be modified to work without SSL-RENEGOTIATION by
>> just establishing a new TCP connection for every new handshake. "
>>
>> So this issue could happen if we do TCP connection for every new TLS
>> connection with renegotiation. I believe this could be fixed if we could
>> block based on max active TLS connections, probably a similar flag for max
>> TLS connections like "tcp_max_connections"
>>
>>
>> Core was generated by `/usr/sbin/kamailio -u swrun -g sw -m 160 -f
>> /etc/kamailio/kamailio.cfg'.
>>
>> Program terminated with signal 11, Segmentation fault.
>> #0 0xb61cc2e3 in ?? () from /usr/lib/kamailio/modules/tls.so
>> (gdb) bt
>> #0 0xb61cc2e3 in ?? () from /usr/lib/kamailio/modules/tls.so
>> #1 0xb65199fd in CRYPTO_lock () from /lib/libcrypto.so.1.0.0
>> #2 0xb658c133 in ?? () from /lib/libcrypto.so.1.0.0
>> #3 0xb658d240 in RAND_add () from /lib/libcrypto.so.1.0.0
>> #4 0xb6690d50 in ssl3_accept () from /lib/libssl.so.1.0.0
>> #5 0xb669bd2f in ssl3_read_bytes () from /lib/libssl.so.1.0.0
>> #6 0xb66989b9 in ?? () from /lib/libssl.so.1.0.0
>> #7 0xb66ae499 in SSL_read () from /lib/libssl.so.1.0.0
>> #8 0xb61e1e33 in tls_read_f () from /usr/lib/kamailio/modules/tls.so
>> #9 0x08177036 in tcp_read_headers ()
>> #10 0x081771f6 in tcp_read_req ()
>> #11 0x08178480 in ?? ()
>> #12 0x0817af77 in tcp_receive_loop ()
>> #13 0x08173597 in tcp_init_children ()
>> #14 0x080b20bf in main_loop ()
>> #15 0x080b38c3 in main ()
>> (gdb)
>>
>>
>>
>> On Wed, Nov 23, 2011 at 10:35 AM, Daniel-Constantin Mierla <
>> miconda at gmail.com> wrote:
>>
>>> Hello,
>>>
>>> 3.1.0 is not the right choice in 3.1 series, there were many fixes that
>>> were added to that release series branch. The latest stable version there
>>> is 3.1.5. Try with it (even better, try with latest version from git branch
>>> 3.1 -- see
>>> http://www.kamailio.org/dokuwiki/doku.php/install:kamailio-3.1.x-from-git
>>> )
>>>
>>> In this way we are sure it is not a bug that was fixed after the time of
>>> releasing 3.1.0 -- config file and database is the same as for 3.1.0.
>>>
>>> Cheers,
>>> Daniel
>>>
>>>
>>> On 11/23/11 4:01 PM, Jijo wrote:
>>>
>>> Thanks I will attach the logs soon..meanwhile here is the kamailio and
>>> openssl version
>>>
>>> OB151:~ # /usr/sbin/kamailio -V
>>> version: kamailio 3.1.0 (i386/linux) 21a375
>>> flags: STATS: Off, USE_IPV6, USE_TCP, USE_TLS, TLS_HOOKS, USE_RAW_SOCKS,
>>> USE_MCAST, DNS_IP_HACK, SHM_MEM, SHM_MMAP, PKG_MALLOC, DBG_QM_MALLOC,
>>> USE_FUTEX, FAST_LOCK-ADAPTIVE_WAIT, USE_DNS_CACHE, USE_DNS_FAILOVER,
>>> USE_NAPTR, USE_DST_BLACKLIST, HAVE_RESOLV_RES
>>> ADAPTIVE_WAIT_LOOPS=1024, MAX_RECV_BUFFER_SIZE 262144, MAX_LISTEN 16,
>>> MAX_URI_SIZE 1024, BUF_SIZE 65535, PKG_SIZE 15MB
>>> poll method support: poll, epoll_lt, epoll_et, sigio_rt, select.
>>> id: 21a375
>>> compiled on 09:22:51 Nov 4 2011 with gcc 4.5.0
>>>
>>>
>>> OB151:~ # openssl version -a
>>> OpenSSL 1.0.0 29 Mar 2010
>>> built on: 2011-05-31 07:52:17.000000000 +0000
>>> platform: linux-elf
>>> options: bn(64,32) rc4(4x,int) des(ptr,risc1,16,long) blowfish(idx)
>>> compiler: gcc -fPIC -DOPENSSL_PIC -DZLIB -DOPENSSL_THREADS -D_REENTRANT
>>> -DDSO_DLFCN -DHAVE_DLFCN_H
>>> -DL_ENDIAN -DTERMIO -O3 -fomit-frame-pointer -Wall -fomit-frame-pointer
>>> -fmessage-length=0 -O2 -Wall
>>> -D_FORTIFY_SOURCE=2 -fstack-protector -funwind-tables
>>> -fasynchronous-unwind-tables -g -Wa,--noexecstack -fomit-frame-pointer
>>> -fno-strict-aliasing
>>> -DTERMIO -Wall -fstack-protector -DOPENSSL_BN_ASM_PART_WORDS
>>> -DOPENSSL_IA32_SSE2
>>> -DOPENSSL_BN_ASM_MONT -DSHA1_ASM -DSHA256_ASM -DSHA512_ASM -DMD5_ASM
>>> -DRMD160_ASM -DAES_ASM -DWHIRLPOOL_ASM
>>> OPENSSLDIR: "/etc/ssl"
>>>
>>>
>>> On Wed, Nov 23, 2011 at 4:44 AM, Daniel-Constantin Mierla <
>>> miconda at gmail.com> wrote:
>>>
>>>> Hello,
>>>>
>>>> (discussion kept only on sr-dev as it is very likely going to require
>>>> mostly devel interaction).
>>>>
>>>> What is the version of kamailio (-V command line option). Also, send
>>>> the verision of openssl library -- there were many bugs in various lib
>>>> versions that had to be workarounded in the module, maybe this is a new one
>>>> that has to be fixed.
>>>>
>>>> Do you get any error message in the syslog at the moment of the crash?
>>>>
>>>> What would be useful is to get the memory operations log, you can get
>>>> it by setting:
>>>>
>>>> memdbg=1
>>>> memlog=1
>>>>
>>>> in config file.
>>>>
>>>> Then repeat the test and make the log available for download somehow
>>>> (if it is too big), from start to the moment of the crash.
>>>>
>>>> Cheers,
>>>> Daniel
>>>>
>>>>
>>>> On 11/22/11 11:30 PM, Jijo wrote:
>>>>
>>>> Hi All,
>>>>
>>>> Kamailio is resetting when we do TLS renegotiation dos attack using the
>>>> tool available at http://www.thc.org/thc-ssl-dos/.
>>>>
>>>> Anybody looked at this issue? How we could resolve it. Any idea?
>>>>
>>>> The core generated for 3 pid's as below
>>>>
>>>> Pid 1:
>>>>
>>>> Core was generated by `/usr/sbin/kamailio -u swrun -g sw -m 120 -f
>>>> /etc/kamailio/kamailio.cfg'.
>>>> Program terminated with signal 11, Segmentation fault.
>>>> #0 atomic_inc_int () at atomic/atomic_x86.h:225
>>>> (gdb) bt
>>>> #0 atomic_inc_int () at atomic/atomic_x86.h:225
>>>> #1 cfg_update_local () at cfg/cfg_struct.h:228
>>>> #2 timer_main () at timer.c:994
>>>> #3 0x080b0579 in main_loop () at main.c:1632
>>>> #4 0x080b1be4 in main (argc=9, argv=0xbfd61e54) at main.c:2446
>>>>
>>>>
>>>> Pid 2:
>>>>
>>>> Core was generated by `/usr/sbin/kamailio -u swrun -g sw -m 120 -f
>>>> /etc/kamailio/kamailio.cfg'.
>>>> Program terminated with signal 11, Segmentation fault.
>>>> #0 0x0819bfe8 in qm_insert_free (qm=0xaf6c5000, p=0xb05eec30,
>>>> file=0xb6fb4140 "tls: tls_init.c", func=0xb6fb4ce0 "ser_free", line=296)
>>>> at mem/q_malloc.c:184
>>>> 184 if (frag->size <= f->size) break;
>>>> (gdb) bt
>>>> #0 0x0819bfe8 in qm_insert_free (qm=0xaf6c5000, p=0xb05eec30,
>>>> file=0xb6fb4140 "tls: tls_init.c", func=0xb6fb4ce0 "ser_free", line=296)
>>>> at mem/q_malloc.c:184
>>>> #1 qm_free (qm=0xaf6c5000, p=0xb05eec30, file=0xb6fb4140 "tls:
>>>> tls_init.c", func=0xb6fb4ce0 "ser_free", line=296) at mem/q_malloc.c:518
>>>> #2 0xb6f95404 in ser_free (ptr=0xb05eec30) at tls_init.c:296
>>>> #3 0xb732e9ba in CRYPTO_free (str=0xb05eec30) at mem.c:391
>>>> #4 0xb7330bee in int_new_ex_data (class_index=5, obj=0xbfd414f4,
>>>> ad=0xbfd41574) at ex_data.c:440
>>>> #5 0xb7330443 in CRYPTO_new_ex_data (class_index=5, obj=0xbfd414f4,
>>>> ad=0xbfd41574) at ex_data.c:575
>>>> #6 0xb73dfde3 in X509_STORE_CTX_init (ctx=0xbfd414f4,
>>>> store=0xafd8b3d0, x509=0xafe08ff0, chain=0x0) at x509_vfy.c:2114
>>>> #7 0xb74b0f31 in ssl3_output_cert_chain (s=0xb0553a10, x=0xafe08ff0)
>>>> at s3_both.c:349
>>>> #8 0xb74a4728 in ssl3_send_server_certificate (s=0xb0553a10) at
>>>> s3_srvr.c:3034
>>>> #9 0xb74a5879 in ssl3_accept (s=0xb0553a10) at s3_srvr.c:353
>>>> #10 0xb74afa8f in ssl3_read_bytes (s=0xb0553a10, type=23,
>>>> buf=0xb0ad44ec "", len=4095, peek=0) at s3_pkt.c:1266
>>>> #11 0xb74ac9c9 in ssl3_read_internal (s=0xb0553a10, buf=0xb0ad44ec,
>>>> len=4095, peek=0) at s3_lib.c:3265
>>>> #12 0xb74c24a9 in SSL_read (s=0xb0553a10, buf=0xb0ad44ec, num=4095) at
>>>> ssl_lib.c:954
>>>> #13 0xb6fad1c3 in tls_read_f (c=0xb0ad431c, flags=0xbfd619c4) at
>>>> tls_server.c:1058
>>>> #14 0x08171c0e in tcp_read_headers (c=0xb0ad431c,
>>>> read_flags=0xbfd619c4) at tcp_read.c:406
>>>> #15 0x08171db8 in tcp_read_req (con=0xb0ad431c, bytes_read=0xbfd619cc,
>>>> read_flags=0xbfd619c4) at tcp_read.c:885
>>>> #16 0x08172f67 in handle_io (fm=<value optimized out>, events=1,
>>>> idx=<value optimized out>) at tcp_read.c:1234
>>>> #17 0x0817583b in io_wait_loop_epoll (unix_sock=89) at io_wait.h:1092
>>>> #18 tcp_receive_loop (unix_sock=89) at tcp_read.c:1345
>>>> #19 0x0816e2e9 in tcp_init_children () at tcp_main.c:4867
>>>> #20 0x080affb1 in main_loop () at main.c:1646
>>>> #21 0x080b1be4 in main (argc=9, argv=0xbfd61e54) at main.c:2446
>>>>
>>>> Pid 3:
>>>>
>>>> Core was generated by `/usr/sbin/kamailio -u swrun -g sw -m 120 -f
>>>> /etc/kamailio/kamailio.cfg'.
>>>> Program terminated with signal 11, Segmentation fault.
>>>> #0 0xb76c9e7c in memmove () from /lib/libc.so.6
>>>> (gdb) bt
>>>> #0 0xb76c9e7c in memmove () from /lib/libc.so.6
>>>> #1 0x081724e7 in tcp_read_req (con=0xb022c8f0, bytes_read=0xbfd619cc,
>>>> read_flags=0xbfd619c4) at tcp_read.c:1026
>>>> #2 0x08172f67 in handle_io (fm=<value optimized out>, events=1,
>>>> idx=<value optimized out>) at tcp_read.c:1234
>>>> #3 0x0817583b in io_wait_loop_epoll (unix_sock=93) at io_wait.h:1092
>>>> #4 tcp_receive_loop (unix_sock=93) at tcp_read.c:1345
>>>> #5 0x0816e2e9 in tcp_init_children () at tcp_main.c:4867
>>>> #6 0x080affb1 in main_loop () at main.c:1646
>>>> #7 0x080b1be4 in main (argc=9, argv=0xbfd61e54) at main.c:2446
>>>>
>>>>
>>>>
>>>>
>>>> _______________________________________________
>>>> sr-dev mailing listsr-dev at lists.sip-router.orghttp://lists.sip-router.org/cgi-bin/mailman/listinfo/sr-dev
>>>>
>>>>
>>>> --
>>>> Daniel-Constantin Mierla -- http://www.asipto.com
>>>> Kamailio Advanced Training, Dec 5-8, Berlin: http://asipto.com/u/kathttp://linkedin.com/in/miconda -- http://twitter.com/miconda
>>>>
>>>>
>>>
>>> --
>>> Daniel-Constantin Mierla -- http://www.asipto.com
>>> Kamailio Advanced Training, Dec 5-8, Berlin: http://asipto.com/u/kathttp://linkedin.com/in/miconda -- http://twitter.com/miconda
>>>
>>>
>>
>
> --
> Daniel-Constantin Mierla -- http://www.asipto.comhttp://linkedin.com/in/miconda -- http://twitter.com/miconda
>
>
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