DH - Revision history

Frankk at 16:41, 25 October 2005

2005-10-25T16:41:30Z

← Older revision		Revision as of 09:41, 25 October 2005
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	; 1. The first peer generates the parameters p (which is a large prime and also a safe prime meaning that (p - 1) / 2 is also prime. It also creates g which OpenSSL calls a generator and is usually a constant of 2 or 5 (both low prime numbers). (DH_generate_parameters())		; 1.: The first peer generates the parameters p (which is a large prime and also a safe prime meaning that (p - 1) / 2 is also prime. It also creates g which OpenSSL calls a generator and is usually a constant of 2 or 5 (both low prime numbers). (DH_generate_parameters())
	; 2. It then shares p and g with the second peer, which fills these into its own struct DH. (DH_new())		; 2. : It then shares p and g with the second peer, which fills these into its own struct DH. (DH_new())
	; 3. The first peer also generates her public and private key now and also shares the public key with the second peer. (DH_generate_key())		; 3. : The first peer also generates her public and private key now and also shares the public key with the second peer. (DH_generate_key())
	; 4. Given p and g the second peer with that creates their own private key and public key (which are different from the first peers)(DH_generate_key()) and		; 4. : Given p and g the second peer with that creates their own private key and public key (which are different from the first peers)(DH_generate_key()) and
	; 5. Shares with the first peer their public key.		; 5. : Shares with the first peer their public key.
	; 6. Given the public key of the other peer, p, g, and their private key both peers are now able to compute a shared secret. (DH_compute_key())		; 6. : Given the public key of the other peer, p, g, and their private key both peers are now able to compute a shared secret. (DH_compute_key())
	; 7. Using this shared secret as the key to a symmetric cipher encrypted communication can now start.		; 7. : Using this shared secret as the key to a symmetric cipher encrypted communication can now start.

Frankk at 16:16, 25 October 2005

2005-10-25T16:16:51Z

← Older revision		Revision as of 09:16, 25 October 2005
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	; 1. : The first peer generates the parameters p (which is a large prime and also a safe prime meaning that (p - 1) / 2 is also prime. It also creates g which OpenSSL calls a generator and is usually a constant of 2 or 5 (both low prime numbers). (DH_generate_parameters())		; 1. The first peer generates the parameters p (which is a large prime and also a safe prime meaning that (p - 1) / 2 is also prime. It also creates g which OpenSSL calls a generator and is usually a constant of 2 or 5 (both low prime numbers). (DH_generate_parameters())
	; 2. : It then shares p and g with the second peer, which fills these into its own struct DH. (DH_new())		; 2. It then shares p and g with the second peer, which fills these into its own struct DH. (DH_new())
	; 3. : The first peer also generates her public and private key now and also shares the public key with the second peer. (DH_generate_key())		; 3. The first peer also generates her public and private key now and also shares the public key with the second peer. (DH_generate_key())
	; 4. : Given p and g the second peer with that creates their own private key and public key (which are different from the first peers)(DH_generate_key()) and		; 4. Given p and g the second peer with that creates their own private key and public key (which are different from the first peers)(DH_generate_key()) and
	; 5. ~~: shares~~ with the first peer their public key.		; 5. Shares with the first peer their public key.
	; 6. : Given the public key of the other peer, p, g, and their private key both peers are now able to compute a shared secret. (DH_compute_key())		; 6. Given the public key of the other peer, p, g, and their private key both peers are now able to compute a shared secret. (DH_compute_key())
	; 7. : Using this shared secret as the key to a symmetric cipher encrypted communication can now start.		; 7. Using this shared secret as the key to a symmetric cipher encrypted communication can now start.

Pbug at 07:06, 11 October 2005

2005-10-11T07:06:38Z

← Older revision		Revision as of 00:06, 11 October 2005
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	Diffie Hellman is a public key cipher developed in 1976 by 2 americans named Whitfield Diffie and Martin Hellman. The protocol exchanges data on both ends of communication to agree mathematically on a common key which can then be used with a symmetric cipher.		Diffie Hellman is a public key cipher developed in 1976 by 2 americans named Whitfield Diffie and Martin Hellman. The protocol exchanges data on both ends of communication to agree mathematically on a common key which can then be used with a symmetric cipher.

	Here is what a Diffie Hellman exchange would look like. Peers mean the endpoints of a 2-way communication. This method alone is susceptible to a [[man-in-middle]] and [[~~timeing~~ attack]]s:		Here is what a Diffie Hellman exchange would look like. Peers mean the endpoints of a 2-way communication. This method alone is susceptible to a [[man-in-middle]] and [[timing attack]]s:

	In OpenSSL struct DH consists of the following members:		In OpenSSL struct DH consists of the following members:

Pbug at 07:06, 11 October 2005

2005-10-11T07:06:14Z

← Older revision		Revision as of 00:06, 11 October 2005
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	Diffie Hellman is a public key cipher developed in 1976 by 2 americans named Whitfield Diffie and Martin Hellman. The protocol exchanges data on both ends of communication to agree mathematically on a common key which can then be used with a symmetric cipher.		Diffie Hellman is a public key cipher developed in 1976 by 2 americans named Whitfield Diffie and Martin Hellman. The protocol exchanges data on both ends of communication to agree mathematically on a common key which can then be used with a symmetric cipher.

	Here is what a Diffie Hellman exchange would look like. Peers mean the endpoints of a 2-way communication. This method alone is susceptible to a [[man-in-middle]] attack:		Here is what a Diffie Hellman exchange would look like. Peers mean the endpoints of a 2-way communication. This method alone is susceptible to a [[man-in-middle]] and [[timeing attack]]s:

	In OpenSSL struct DH consists of the following members:		In OpenSSL struct DH consists of the following members:

Pbug at 07:01, 11 October 2005

2005-10-11T07:01:45Z

← Older revision		Revision as of 00:01, 11 October 2005
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	Diffie Hellman is a public key cipher developed in 1976 by 2 americans named Whitfield Diffie and Martin Hellman. The protocol exchanges data on both ~~end~~ of communication to agree mathematically on a common key which can then be used with a symmetric cipher.		Diffie Hellman is a public key cipher developed in 1976 by 2 americans named Whitfield Diffie and Martin Hellman. The protocol exchanges data on both ends of communication to agree mathematically on a common key which can then be used with a symmetric cipher.

	Here is what a Diffie Hellman exchange would look like. Peers mean the endpoints of a 2-way communication. This method alone is susceptible to a [[man-in-middle]] attack:		Here is what a Diffie Hellman exchange would look like. Peers mean the endpoints of a 2-way communication. This method alone is susceptible to a [[man-in-middle]] attack:

Pbug at 06:42, 11 October 2005

2005-10-11T06:42:18Z

← Older revision		Revision as of 23:42, 10 October 2005
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	; 5. : shares with the first peer their public key.		; 5. : shares with the first peer their public key.
	; 6. : Given the public key of the other peer, p, g, and their private key both peers are now able to compute a shared secret. (DH_compute_key())		; 6. : Given the public key of the other peer, p, g, and their private key both peers are now able to compute a shared secret. (DH_compute_key())
			; 7. : Using this shared secret as the key to a symmetric cipher encrypted communication can now start.

Pbug at 06:31, 11 October 2005

2005-10-11T06:31:50Z

← Older revision		Revision as of 23:31, 10 October 2005
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	; 1. : The first peer generates the parameters p (which is a large prime and also a safe prime meaning that (p - 1) / 2 is also prime. It also creates g which OpenSSL calls a generator and is usually a constant of 2 or 5 (both low prime numbers).		; 1. : The first peer generates the parameters p (which is a large prime and also a safe prime meaning that (p - 1) / 2 is also prime. It also creates g which OpenSSL calls a generator and is usually a constant of 2 or 5 (both low prime numbers). (DH_generate_parameters())
	; 2. : It then shares p and g with the second peer, which fills these into its own struct DH.		; 2. : It then shares p and g with the second peer, which fills these into its own struct DH. (DH_new())
	; 3. : The first peer also generates her public and private key now and also shares the public key with the second peer.		; 3. : The first peer also generates her public and private key now and also shares the public key with the second peer. (DH_generate_key())
	; 4. : Given p and g the second peer with that creates their own private key and public key (which are different from the first peers) and		; 4. : Given p and g the second peer with that creates their own private key and public key (which are different from the first peers)(DH_generate_key()) and
	; 5. : shares with the first peer their public key.		; 5. : shares with the first peer their public key.
	; 6. : Given the public key of the other peer, p, g, and their private key both peers are now able to compute a shared secret.		; 6. : Given the public key of the other peer, p, g, and their private key both peers are now able to compute a shared secret. (DH_compute_key())

Pbug at 06:27, 11 October 2005

2005-10-11T06:27:54Z

← Older revision		Revision as of 23:27, 10 October 2005
Line 11:		Line 11:


	; 1. : The first peer generates the parameters p (which is a large prime and also a safe prime meaning that (p - 1) / 2 is also prime). It also creates g which OpenSSL calls a generator and is usually a constant of 2 or 5 (both low prime numbers).		; 1. : The first peer generates the parameters p (which is a large prime and also a safe prime meaning that (p - 1) / 2 is also prime. It also creates g which OpenSSL calls a generator and is usually a constant of 2 or 5 (both low prime numbers).
	; 2. : It then shares p and g with the second peer, which fills these into its own struct DH.		; 2. : It then shares p and g with the second peer, which fills these into its own struct DH.
	; 3. : The first peer also generates her public and private key now and also shares the public key with the second peer.		; 3. : The first peer also generates her public and private key now and also shares the public key with the second peer.

Pbug at 06:27, 11 October 2005

2005-10-11T06:27:05Z

← Older revision		Revision as of 23:27, 10 October 2005
Line 5:		Line 5:
	In OpenSSL struct DH consists of the following members:		In OpenSSL struct DH consists of the following members:

	BIGNUM *p;		; BIGNUM *p;
	BIGNUM *g;		; BIGNUM *g;
	BIGNUM *public_key;		; BIGNUM *public_key;
	BIGNUM *private_key;		; BIGNUM *private_key;


	1. The first peer generates the parameters p (which is a large prime and also a safe prime meaning that (p - 1) / 2 is also prime). It also creates g which OpenSSL calls a generator and is usually a constant of 2 or 5 (both low prime numbers).		; 1. : The first peer generates the parameters p (which is a large prime and also a safe prime meaning that (p - 1) / 2 is also prime). It also creates g which OpenSSL calls a generator and is usually a constant of 2 or 5 (both low prime numbers).
	2. It then shares p and g with the second peer, which fills these into its own struct DH.		; 2. : It then shares p and g with the second peer, which fills these into its own struct DH.
	3. The first peer also generates her public and private key now and also shares the public key with the second peer.		; 3. : The first peer also generates her public and private key now and also shares the public key with the second peer.
	4. Given p and g the second peer with that creates their own private key and public key (which are different from the first peers) and		; 4. : Given p and g the second peer with that creates their own private key and public key (which are different from the first peers) and
	5. shares with the first peer their public key.		; 5. : shares with the first peer their public key.
	6. Given the public key of the other peer, p, g, and their private key both peers are now able to compute a shared secret.		; 6. : Given the public key of the other peer, p, g, and their private key both peers are now able to compute a shared secret.

Pbug at 06:24, 11 October 2005

2005-10-11T06:24:18Z

New page

Diffie Hellman is a public key cipher developed in 1976 by 2 americans named Whitfield Diffie and Martin Hellman. The protocol exchanges data on both end of communication to agree mathematically on a common key which can then be used with a symmetric cipher.

Here is what a Diffie Hellman exchange would look like. Peers mean the endpoints of a 2-way communication. This method alone is susceptible to a [[man-in-middle]] attack:

In OpenSSL struct DH consists of the following members:

BIGNUM *p;
BIGNUM *g;
BIGNUM *public_key;
BIGNUM *private_key;

1. The first peer generates the parameters p (which is a large prime and also a safe prime meaning that (p - 1) / 2 is also prime). It also creates g which OpenSSL calls a generator and is usually a constant of 2 or 5 (both low prime numbers).
2. It then shares p and g with the second peer, which fills these into its own struct DH.
3. The first peer also generates her public and private key now and also shares the public key with the second peer.
4. Given p and g the second peer with that creates their own private key and public key (which are different from the first peers) and
5. shares with the first peer their public key.
6. Given the public key of the other peer, p, g, and their private key both peers are now able to compute a shared secret.