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diff --git a/other/openssh-reverse/OVERVIEW b/other/openssh-reverse/OVERVIEW
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+This document is intended for those who wish to read the ssh source
+code.  This tries to give an overview of the structure of the code.
+      
+Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>
+Updated 17 Nov 1995.
+Updated 19 Oct 1999 for OpenSSH-1.2
+The software consists of ssh (client), sshd (server), scp, sdist, and
+the auxiliary programs ssh-keygen, ssh-agent, ssh-add, and
+make-ssh-known-hosts.  The main program for each of these is in a .c
+file with the same name.
+There are some subsystems/abstractions that are used by a number of
+these programs.
+  Buffer manipulation routines
+      
+    - These provide an arbitrary size buffer, where data can be appended.
+      Data can be consumed from either end.  The code is used heavily
+      throughout ssh.  The basic buffer manipulation functions are in
+      buffer.c (header buffer.h), and additional code to manipulate specific
+      data types is in bufaux.c.
+  Compression Library
+  
+    - Ssh uses the GNU GZIP compression library (ZLIB).
+  Encryption/Decryption
+    - Ssh contains several encryption algorithms.  These are all
+      accessed through the cipher.h interface.  The interface code is
+      in cipher.c, and the implementations are in libc.
+  Multiple Precision Integer Library
+    - Uses the SSLeay BIGNUM sublibrary.
+    - Some auxiliary functions for mp-int manipulation are in mpaux.c.
+  Random Numbers
+    - Uses arc4random() and such.
+  RSA key generation, encryption, decryption
+    - Ssh uses the RSA routines in libssl.
+  RSA key files
+    - RSA keys are stored in files with a special format.  The code to
+      read/write these files is in authfile.c.  The files are normally
+      encrypted with a passphrase.  The functions to read passphrases
+      are in readpass.c (the same code is used to read passwords).
+  Binary packet protocol
+    - The ssh binary packet protocol is implemented in packet.c.  The
+      code in packet.c does not concern itself with packet types or their
+      execution; it contains code to build packets, to receive them and
+      extract data from them, and the code to compress and/or encrypt
+      packets.  CRC code comes from crc32.c.
+    - The code in packet.c calls the buffer manipulation routines
+      (buffer.c, bufaux.c), compression routines (compress.c, zlib),
+      and the encryption routines.
+  X11, TCP/IP, and Agent forwarding
+    - Code for various types of channel forwarding is in channels.c.
+      The file defines a generic framework for arbitrary communication
+      channels inside the secure channel, and uses this framework to
+      implement X11 forwarding, TCP/IP forwarding, and authentication
+      agent forwarding.
+      The new, Protocol 1.5, channel close implementation is in nchan.c
+  Authentication agent
+    - Code to communicate with the authentication agent is in authfd.c.
+  Authentication methods
+    - Code for various authentication methods resides in auth-*.c
+      (auth-passwd.c, auth-rh-rsa.c, auth-rhosts.c, auth-rsa.c).  This
+      code is linked into the server.  The routines also manipulate
+      known hosts files using code in hostfile.c.  Code in canohost.c
+      is used to retrieve the canonical host name of the remote host.
+      Code in match.c is used to match host names.  
+    - In the client end, authentication code is in sshconnect.c.  It
+      reads Passwords/passphrases using code in readpass.c.  It reads
+      RSA key files with authfile.c.  It communicates the
+      authentication agent using authfd.c.
+  The ssh client
+    - The client main program is in ssh.c.  It first parses arguments
+      and reads configuration (readconf.c), then calls ssh_connect (in
+      sshconnect.c) to open a connection to the server (possibly via a
+      proxy), and performs authentication (ssh_login in sshconnect.c).
+      It then makes any pty, forwarding, etc. requests.  It may call
+      code in ttymodes.c to encode current tty modes.  Finally it
+      calls client_loop in clientloop.c.  This does the real work for
+      the session.
+    - The client is suid root.  It tries to temporarily give up this
+      rights while reading the configuration data.  The root
+      privileges are only used to make the connection (from a
+      privileged socket).  Any extra privileges are dropped before
+      calling ssh_login.
+  Pseudo-tty manipulation and tty modes
+    - Code to allocate and use a pseudo tty is in pty.c.  Code to
+      encode and set terminal modes is in ttymodes.c.
+  Logging in (updating utmp, lastlog, etc.)
+    - The code to do things that are done when a user logs in are in
+      login.c.  This includes things such as updating the utmp, wtmp,
+      and lastlog files.  Some of the code is in sshd.c.
+  Writing to the system log and terminal
+    - The programs use the functions fatal(), log(), debug(), error()
+      in many places to write messages to system log or user's
+      terminal.  The implementation that logs to system log is in
+      log-server.c; it is used in the server program.  The other
+      programs use an implementation that sends output to stderr; it
+      is in log-client.c.  The definitions are in ssh.h.
+  The sshd server (daemon)
+    - The sshd daemon starts by processing arguments and reading the
+      configuration file (servconf.c).  It then reads the host key,
+      starts listening for connections, and generates the server key.
+      The server key will be regenerated every hour by an alarm.
+    - When the server receives a connection, it forks, disables the
+      regeneration alarm, and starts communicating with the client.
+      They first perform identification string exchange, then
+      negotiate encryption, then perform authentication, preparatory
+      operations, and finally the server enters the normal session
+      mode by calling server_loop in serverloop.c.  This does the real
+      work, calling functions in other modules.
+      
+    - The code for the server is in sshd.c.  It contains a lot of
+      stuff, including:
+        - server main program
+        - waiting for connections
+        - processing new connection
+        - authentication
+        - preparatory operations
+        - building up the execution environment for the user program
+        - starting the user program.
+  Auxiliary files
+    - There are several other files in the distribution that contain
+      various auxiliary routines:
+        ssh.h        the main header file for ssh (various definitions)
+        getput.h     byte-order independent storage of integers
+        includes.h   includes most system headers.  Lots of #ifdefs.
+        tildexpand.c expand tilde in file names
+        uidswap.c    uid-swapping
+        xmalloc.c    "safe" malloc routines

diff --git a/other/openssh-reverse/OVERVIEW b/other/openssh-reverse/OVERVIEW new file mode 100644 index 0000000..7f34ac4 --- /dev/null +++ b/other/openssh-reverse/OVERVIEW
@@ -0,0 +1,164 @@
	1	This document is intended for those who wish to read the ssh source
	2	code. This tries to give an overview of the structure of the code.
	3
	4	Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>
	5	Updated 17 Nov 1995.
	6	Updated 19 Oct 1999 for OpenSSH-1.2
	7
	8	The software consists of ssh (client), sshd (server), scp, sdist, and
	9	the auxiliary programs ssh-keygen, ssh-agent, ssh-add, and
	10	make-ssh-known-hosts. The main program for each of these is in a .c
	11	file with the same name.
	12
	13	There are some subsystems/abstractions that are used by a number of
	14	these programs.
	15
	16	Buffer manipulation routines
	17
	18	- These provide an arbitrary size buffer, where data can be appended.
	19	Data can be consumed from either end. The code is used heavily
	20	throughout ssh. The basic buffer manipulation functions are in
	21	buffer.c (header buffer.h), and additional code to manipulate specific
	22	data types is in bufaux.c.
	23
	24	Compression Library
	25
	26	- Ssh uses the GNU GZIP compression library (ZLIB).
	27
	28	Encryption/Decryption
	29
	30	- Ssh contains several encryption algorithms. These are all
	31	accessed through the cipher.h interface. The interface code is
	32	in cipher.c, and the implementations are in libc.
	33
	34	Multiple Precision Integer Library
	35
	36	- Uses the SSLeay BIGNUM sublibrary.
	37	- Some auxiliary functions for mp-int manipulation are in mpaux.c.
	38
	39	Random Numbers
	40
	41	- Uses arc4random() and such.
	42
	43	RSA key generation, encryption, decryption
	44
	45	- Ssh uses the RSA routines in libssl.
	46
	47	RSA key files
	48
	49	- RSA keys are stored in files with a special format. The code to
	50	read/write these files is in authfile.c. The files are normally
	51	encrypted with a passphrase. The functions to read passphrases
	52	are in readpass.c (the same code is used to read passwords).
	53
	54	Binary packet protocol
	55
	56	- The ssh binary packet protocol is implemented in packet.c. The
	57	code in packet.c does not concern itself with packet types or their
	58	execution; it contains code to build packets, to receive them and
	59	extract data from them, and the code to compress and/or encrypt
	60	packets. CRC code comes from crc32.c.
	61
	62	- The code in packet.c calls the buffer manipulation routines
	63	(buffer.c, bufaux.c), compression routines (compress.c, zlib),
	64	and the encryption routines.
	65
	66	X11, TCP/IP, and Agent forwarding
	67
	68	- Code for various types of channel forwarding is in channels.c.
	69	The file defines a generic framework for arbitrary communication
	70	channels inside the secure channel, and uses this framework to
	71	implement X11 forwarding, TCP/IP forwarding, and authentication
	72	agent forwarding.
	73	The new, Protocol 1.5, channel close implementation is in nchan.c
	74
	75	Authentication agent
	76
	77	- Code to communicate with the authentication agent is in authfd.c.
	78
	79	Authentication methods
	80
	81	- Code for various authentication methods resides in auth-*.c
	82	(auth-passwd.c, auth-rh-rsa.c, auth-rhosts.c, auth-rsa.c). This
	83	code is linked into the server. The routines also manipulate
	84	known hosts files using code in hostfile.c. Code in canohost.c
	85	is used to retrieve the canonical host name of the remote host.
	86	Code in match.c is used to match host names.
	87
	88	- In the client end, authentication code is in sshconnect.c. It
	89	reads Passwords/passphrases using code in readpass.c. It reads
	90	RSA key files with authfile.c. It communicates the
	91	authentication agent using authfd.c.
	92
	93	The ssh client
	94
	95	- The client main program is in ssh.c. It first parses arguments
	96	and reads configuration (readconf.c), then calls ssh_connect (in
	97	sshconnect.c) to open a connection to the server (possibly via a
	98	proxy), and performs authentication (ssh_login in sshconnect.c).
	99	It then makes any pty, forwarding, etc. requests. It may call
	100	code in ttymodes.c to encode current tty modes. Finally it
	101	calls client_loop in clientloop.c. This does the real work for
	102	the session.
	103
	104	- The client is suid root. It tries to temporarily give up this
	105	rights while reading the configuration data. The root
	106	privileges are only used to make the connection (from a
	107	privileged socket). Any extra privileges are dropped before
	108	calling ssh_login.
	109
	110	Pseudo-tty manipulation and tty modes
	111
	112	- Code to allocate and use a pseudo tty is in pty.c. Code to
	113	encode and set terminal modes is in ttymodes.c.
	114
	115	Logging in (updating utmp, lastlog, etc.)
	116
	117	- The code to do things that are done when a user logs in are in
	118	login.c. This includes things such as updating the utmp, wtmp,
	119	and lastlog files. Some of the code is in sshd.c.
	120
	121	Writing to the system log and terminal
	122
	123	- The programs use the functions fatal(), log(), debug(), error()
	124	in many places to write messages to system log or user's
	125	terminal. The implementation that logs to system log is in
	126	log-server.c; it is used in the server program. The other
	127	programs use an implementation that sends output to stderr; it
	128	is in log-client.c. The definitions are in ssh.h.
	129
	130	The sshd server (daemon)
	131
	132	- The sshd daemon starts by processing arguments and reading the
	133	configuration file (servconf.c). It then reads the host key,
	134	starts listening for connections, and generates the server key.
	135	The server key will be regenerated every hour by an alarm.
	136
	137	- When the server receives a connection, it forks, disables the
	138	regeneration alarm, and starts communicating with the client.
	139	They first perform identification string exchange, then
	140	negotiate encryption, then perform authentication, preparatory
	141	operations, and finally the server enters the normal session
	142	mode by calling server_loop in serverloop.c. This does the real
	143	work, calling functions in other modules.
	144
	145	- The code for the server is in sshd.c. It contains a lot of
	146	stuff, including:
	147	- server main program
	148	- waiting for connections
	149	- processing new connection
	150	- authentication
	151	- preparatory operations
	152	- building up the execution environment for the user program
	153	- starting the user program.
	154
	155	Auxiliary files
	156
	157	- There are several other files in the distribution that contain
	158	various auxiliary routines:
	159	ssh.h the main header file for ssh (various definitions)
	160	getput.h byte-order independent storage of integers
	161	includes.h includes most system headers. Lots of #ifdefs.
	162	tildexpand.c expand tilde in file names
	163	uidswap.c uid-swapping
	164	xmalloc.c "safe" malloc routines