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Change format of rules output by print-types.zeek #6

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Mar 25, 2020

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@henridf henridf commented Mar 25, 2020

They were previously like this {"_path": "http", "descriptor": "conn_log"} and this PR changes them to be like this {"name": "_path", "value": "http", "descriptor": "conn_log"}, which is easier to validate and handle programmatically. The former representation was intended to allow matching rules on multiple fields, but that doesn't seem likely to be a necessary feature any time soon.

they were previously like this:
{"_path": "http", "descriptor": "conn_log"}

and are now like this:
{"name": "_path", "value": "http", "descriptor": "conn_log"}

which is easier to validate and handle programmatically.
@henridf henridf requested a review from a team March 25, 2020 13:15
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henridf commented Mar 25, 2020

(The types.json that is stored in https://github.com/brimsec/zq already reflects this change.)

@henridf henridf requested a review from philrz March 25, 2020 13:22
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Works for me! Thanks for the heads-up. 👍

@henridf henridf merged commit 4fb3e55 into master Mar 25, 2020
@henridf henridf deleted the simplify-rule-format branch March 25, 2020 14:58
nwt pushed a commit that referenced this pull request Apr 24, 2020
…cket

An attacker can make Zeek crash by posting the KEX packet twice, which
will result in an assertion failure in binpac::datastring::init():

 #0  __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:50
 #1  0x00007ffff5196535 in __GI_abort () at abort.c:79
 #2  0x00007ffff519640f in __assert_fail_base (fmt=0x7ffff52f86e0 "%s%s%s:%u: %s%sAssertion `%s' failed.\n%n", assertion=0x1d33530 "!data_",
     file=0x1d33537 "aux/binpac/lib/binpac_bytestring.h", line=108, function=<optimized out>) at assert.c:92
 #3  0x00007ffff51a3b92 in __GI___assert_fail (assertion=0x1d33530 "!data_", file=0x1d33537 "aux/binpac/lib/binpac_bytestring.h",
     line=108, function=0x1d3356c "void binpac::datastring<unsigned char>::init(const T *, int) [T = unsigned char]") at assert.c:101
 #4  0x0000000000c1e970 in binpac::datastring<unsigned char>::init (this=0x608000d609d0, begin=0x603001bdd1d0 "diffie-hellman-group16-sha512", length=29)
     at aux/binpac/lib/binpac_bytestring.h:108
 #5  0x0000000000e9ab60 in binpac::SSH::SSH_Conn::update_kex (this=0x608000d609a0, algs=..., orig=true) at src/analyzer/protocol/ssh/ssh_pac.cc:205
 #6  0x0000000000ea0d06 in binpac::SSH::SSH2_KEXINIT::Parse (this=0x60b000734680,
     t_begin_of_data=0x621000004753 "\200\275\a%\223\023Y8\204t\235\363!\031I.", t_end_of_data=0x621000004b85 "ޭ\276", <incomplete sequence \357>,
     t_context=0x603001bdcc90, t_byteorder=0) at src/analyzer/protocol/ssh/ssh_pac.cc:1598
 #7  0x0000000000e9f8f4 in binpac::SSH::SSH2_Message::Parse (this=0x608000d60ea0,
     t_begin_of_data=0x621000004753 "\200\275\a%\223\023Y8\204t\235\363!\031I.", t_end_of_data=0x621000004b85 "ޭ\276", <incomplete sequence \357>,
     t_context=0x603001bdcc90, t_byteorder=0) at src/analyzer/protocol/ssh/ssh_pac.cc:1326
 #8  0x0000000000e9d7e1 in binpac::SSH::SSH2_Key_Exchange::Parse (this=0x604001779850,
     t_begin_of_data=0x621000004751 "\006\024\200\275\a%\223\023Y8\204t\235\363!\031I.", t_end_of_data=0x621000004b85 "ޭ\276", <incomplete sequence \357>,
     t_context=0x603001bdcc90, t_byteorder=0) at src/analyzer/protocol/ssh/ssh_pac.cc:1210
 #9  0x0000000000e9c981 in binpac::SSH::SSH_Key_Exchange::ParseBuffer (this=0x603001bdccc0, t_flow_buffer=0x608000d60a20, t_context=0x603001bdcc90,
     t_byteorder=0) at src/analyzer/protocol/ssh/ssh_pac.cc:628
 #10 0x0000000000e9c26c in binpac::SSH::SSH_PDU::ParseBuffer (this=0x604001779810, t_flow_buffer=0x608000d60a20, t_context=0x603001bdcc90)
     at src/analyzer/protocol/ssh/ssh_pac.cc:446
 #11 0x0000000000ea6f04 in binpac::SSH::SSH_Flow::NewData (this=0x604001774690, t_begin_of_data=0x62100000474d "",
     t_end_of_data=0x621000004b85 "ޭ\276", <incomplete sequence \357>) at src/analyzer/protocol/ssh/ssh_pac.cc:3071
 #12 0x0000000000e9a38f in binpac::SSH::SSH_Conn::NewData (this=0x608000d609a0, is_orig=true, begin=0x62100000474d "",
     end=0x621000004b85 "ޭ\276", <incomplete sequence \357>) at src/analyzer/protocol/ssh/ssh_pac.cc:63
 #13 0x0000000000e98335 in analyzer::SSH::SSH_Analyzer::DeliverStream (this=0x7fffffffdd40, len=1080, data=0x62100000474d "", orig=true)
     at src/analyzer/protocol/ssh/SSH.cc:68

With assertions turned off, this would "only" be a memory leak.

This commit fixes the vulnerability by freeing and clearing the
`binpac::datastring` before assigning a new value.
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