Re: Question on OpenSSL encryption
Hi, In addition to the online material, are there any good books which we can refer to understand openSSL better? Both conceptually as well as from the API/code perspective. We hear of the Network Security with OpenSSL by John Viega as one good reference. But it was published in 2002. Any good new books which can be used? Regds, Ashok On Sat, Jan 7, 2012 at 11:44 PM, Ben Laurie b...@links.org wrote: On Sat, Jan 7, 2012 at 4:12 PM, Manish Jain invalid.poin...@gmail.com wrote: Hello Michael/Anyone Else, Can you be kind enough to please point me to some place/URL where I can get a bit more information about how the key is negotiated upon ? I have gone through a a couple of write-ups on OpenSSL which throw light upon everything else except for this vital piece of information. http://en.wikipedia.org/wiki/Transport_Layer_Security Thanks Regards Manish Jain On 07-Jan-12 19:23, Michael S. Zick wrote: On Sat January 7 2012, Manish Jain wrote: Hi, I am new to OpenSSL and am trying to prepare some illustrative documentation on how it works. AFAIK, OpenSSL uses the concept of a pair of keys per host : one is a private key which is never communicated to any other host, and the other is a public key which is transmitted to the peer (the other party). The client uses the public key of the server (contained in the server's certificate) to encrypt its communication, which can only be decrypted with the server's private key. Please correct me if I am wrong. That is the essence of what happens and by that the client knows that it is communicating with the server it intended to reach (authentication). Now the question is : when the server sends data to the client, what key does it use for encryption ? The general answer is: The client and server establish a shared key for that propose early in the protocol. Does the client communicate its public key to the server (at some initial stage) which the server uses for encryption ? If the communications set up between the two requires client authentication. In many cases the client remains a stranger to the server (un-authenticated). If yes, what if the client does not have a pair of public/private keys ? The usual case for public web browsing using https and some other protocols. The client remains a stranger to the server. The question arises because it does not seem logical that the server would its private key for encrypting data to be sent to the client. Else, snoopers who might have picked the public key could decrypt the data too. There is an early stage in nearly all protocols, called: key agreement where the client and server agree on a key without exchanging any of the 'private' information that it is based on. Any help on clearing up the above points would be greatly appreciated. My comments above are at a very general level. If the process was as simple as my answers, OpenSSL would not be as large a body of code as it is. ;-) Mike Thank you Regards Manish Jain invalid.poin...@gmail.com __ OpenSSL Project http://www.openssl.org User Support Mailing Listopenssl-users@openssl.org Automated List Manager majord...@openssl.org __ OpenSSL Project http://www.openssl.org User Support Mailing Listopenssl-users@openssl.org Automated List Manager majord...@openssl.org __ OpenSSL Project http://www.openssl.org User Support Mailing Listopenssl-users@openssl.org Automated List Manager majord...@openssl.org __ OpenSSL Project http://www.openssl.org User Support Mailing Listopenssl-users@openssl.org Automated List Manager majord...@openssl.org
Re: Question on OpenSSL encryption
Am 09.01.2012 13:10, schrieb Ashok C: Hi, In addition to the online material, are there any good books which we can refer to understand openSSL better? Both conceptually as well as from the API/code perspective. We hear of the Network Security with OpenSSL by John Viega as one good reference. But it was published in 2002. Any good new books which can be used? Well, the questions of the original poster weren't OpenSSL specific, but targeted SSL/TLS in general, for this Eric Rescorla's book SSL and TLS: Building and Designing Secure Systems is the better book. Sadly being from the year 2000 it is somewhat outdated too, but nevertheless a good introduction to SSL/TLS. For a description of the OpenSSL API afaik the book from Viega et al. is still the most detailed book, despite being somewhat outdated. For newer versions of TLS (i.e. 1.1 and beyond) one should check newer TLS books, e.g. the ones from Joshua Davies or Rolf Oppliger. Until now i had none of the two books in my hands so i can't you tell more about the books, but maybe a visit at Amazon or similar book traders will give you at least a detailed content description. Ciao, Richard __ OpenSSL Project http://www.openssl.org User Support Mailing Listopenssl-users@openssl.org Automated List Manager majord...@openssl.org
Re: Question on OpenSSL encryption
Thanks Richard, What I am looking would be any good book which gives details about SSL communication like use of certificates, verification of certificates, APIs to examine certificates, certificate revocation concepts/SSL APIs for that, etc. Regds, Ashok 2012/1/9 Richard Könning richard.koenn...@ts.fujitsu.com Am 09.01.2012 13:10, schrieb Ashok C: Hi, In addition to the online material, are there any good books which we can refer to understand openSSL better? Both conceptually as well as from the API/code perspective. We hear of the Network Security with OpenSSL by John Viega as one good reference. But it was published in 2002. Any good new books which can be used? Well, the questions of the original poster weren't OpenSSL specific, but targeted SSL/TLS in general, for this Eric Rescorla's book SSL and TLS: Building and Designing Secure Systems is the better book. Sadly being from the year 2000 it is somewhat outdated too, but nevertheless a good introduction to SSL/TLS. For a description of the OpenSSL API afaik the book from Viega et al. is still the most detailed book, despite being somewhat outdated. For newer versions of TLS (i.e. 1.1 and beyond) one should check newer TLS books, e.g. the ones from Joshua Davies or Rolf Oppliger. Until now i had none of the two books in my hands so i can't you tell more about the books, but maybe a visit at Amazon or similar book traders will give you at least a detailed content description. Ciao, Richard __**__**__ OpenSSL Project http://www.openssl.org User Support Mailing Listopenssl-users@openssl.org Automated List Manager majord...@openssl.org
RE: Question on OpenSSL encryption
I have struggled with SSL/TLS in the past. Good list of books. I checked amazon's table of contents and it looks like Joshua Davies has written a more comprehensive book with lots of code. Clearly it seems to me to be a better book with good reviews. Rolf Oppliger's book is more than twice the cost of the former and did not seem to have code. The former seems to be more technical than the latter. I would like to buy Davies. Neither is specifically about OpenSSL. Anybody agree ? Thanks, Mohan From: owner-openssl-us...@openssl.org [mailto:owner-openssl-us...@openssl.org] On Behalf Of Ashok C Sent: Monday, January 09, 2012 8:15 PM To: openssl-users@openssl.org Cc: richard.koenn...@ts.fujitsu.com Subject: Re: Question on OpenSSL encryption Thanks Richard, What I am looking would be any good book which gives details about SSL communication like use of certificates, verification of certificates, APIs to examine certificates, certificate revocation concepts/SSL APIs for that, etc. Regds, Ashok 2012/1/9 Richard Könning richard.koenn...@ts.fujitsu.com Am 09.01.2012 13:10, schrieb Ashok C: Hi, In addition to the online material, are there any good books which we can refer to understand openSSL better? Both conceptually as well as from the API/code perspective. We hear of the Network Security with OpenSSL by John Viega as one good reference. But it was published in 2002. Any good new books which can be used? Well, the questions of the original poster weren't OpenSSL specific, but targeted SSL/TLS in general, for this Eric Rescorla's book SSL and TLS: Building and Designing Secure Systems is the better book. Sadly being from the year 2000 it is somewhat outdated too, but nevertheless a good introduction to SSL/TLS. For a description of the OpenSSL API afaik the book from Viega et al. is still the most detailed book, despite being somewhat outdated. For newer versions of TLS (i.e. 1.1 and beyond) one should check newer TLS books, e.g. the ones from Joshua Davies or Rolf Oppliger. Until now i had none of the two books in my hands so i can't you tell more about the books, but maybe a visit at Amazon or similar book traders will give you at least a detailed content description. Ciao, Richard __ OpenSSL Project http://www.openssl.org User Support Mailing Listopenssl-users@openssl.org Automated List Manager majord...@openssl.org DISCLAIMER: ==The information contained in this e-mail message may be privileged and/or confidential and protected from disclosure under applicable law. It is intended only for the individual to whom or entity to which it is addressed as shown at the beginning of the message. If the reader of this message is not the intended recipient, or if the employee or agent responsible for delivering the message is not an employee or agent of the intended recipient, you are hereby notified that any review, dissemination,distribution, use, or copying of this message is strictly prohibited. If you have received this message in error, please notify us immediately by return e-mail and permanently delete this message and your reply to the extent it includes this message. Any views or opinions presented in this message or attachments are those of the author and do not necessarily represent those of the Company. All e-mails and attachments sent and received are subject to monitoring, reading, and archival by the Company.==
Re: Question on OpenSSL encryption
On Sat, Jan 7, 2012 at 4:12 PM, Manish Jain invalid.poin...@gmail.com wrote: Hello Michael/Anyone Else, Can you be kind enough to please point me to some place/URL where I can get a bit more information about how the key is negotiated upon ? I have gone through a a couple of write-ups on OpenSSL which throw light upon everything else except for this vital piece of information. http://en.wikipedia.org/wiki/Transport_Layer_Security Thanks Regards Manish Jain On 07-Jan-12 19:23, Michael S. Zick wrote: On Sat January 7 2012, Manish Jain wrote: Hi, I am new to OpenSSL and am trying to prepare some illustrative documentation on how it works. AFAIK, OpenSSL uses the concept of a pair of keys per host : one is a private key which is never communicated to any other host, and the other is a public key which is transmitted to the peer (the other party). The client uses the public key of the server (contained in the server's certificate) to encrypt its communication, which can only be decrypted with the server's private key. Please correct me if I am wrong. That is the essence of what happens and by that the client knows that it is communicating with the server it intended to reach (authentication). Now the question is : when the server sends data to the client, what key does it use for encryption ? The general answer is: The client and server establish a shared key for that propose early in the protocol. Does the client communicate its public key to the server (at some initial stage) which the server uses for encryption ? If the communications set up between the two requires client authentication. In many cases the client remains a stranger to the server (un-authenticated). If yes, what if the client does not have a pair of public/private keys ? The usual case for public web browsing using https and some other protocols. The client remains a stranger to the server. The question arises because it does not seem logical that the server would its private key for encrypting data to be sent to the client. Else, snoopers who might have picked the public key could decrypt the data too. There is an early stage in nearly all protocols, called: key agreement where the client and server agree on a key without exchanging any of the 'private' information that it is based on. Any help on clearing up the above points would be greatly appreciated. My comments above are at a very general level. If the process was as simple as my answers, OpenSSL would not be as large a body of code as it is. ;-) Mike Thank you Regards Manish Jain invalid.poin...@gmail.com __ OpenSSL Project http://www.openssl.org User Support Mailing List openssl-users@openssl.org Automated List Manager majord...@openssl.org __ OpenSSL Project http://www.openssl.org User Support Mailing List openssl-users@openssl.org Automated List Manager majord...@openssl.org __ OpenSSL Project http://www.openssl.org User Support Mailing List openssl-users@openssl.org Automated List Manager majord...@openssl.org __ OpenSSL Project http://www.openssl.org User Support Mailing Listopenssl-users@openssl.org Automated List Manager majord...@openssl.org
Re: Question on OpenSSL encryption
On Sat January 7 2012, Manish Jain wrote: Hi, I am new to OpenSSL and am trying to prepare some illustrative documentation on how it works. AFAIK, OpenSSL uses the concept of a pair of keys per host : one is a private key which is never communicated to any other host, and the other is a public key which is transmitted to the peer (the other party). The client uses the public key of the server (contained in the server's certificate) to encrypt its communication, which can only be decrypted with the server's private key. Please correct me if I am wrong. That is the essence of what happens and by that the client knows that it is communicating with the server it intended to reach (authentication). Now the question is : when the server sends data to the client, what key does it use for encryption ? The general answer is: The client and server establish a shared key for that propose early in the protocol. Does the client communicate its public key to the server (at some initial stage) which the server uses for encryption ? If the communications set up between the two requires client authentication. In many cases the client remains a stranger to the server (un-authenticated). If yes, what if the client does not have a pair of public/private keys ? The usual case for public web browsing using https and some other protocols. The client remains a stranger to the server. The question arises because it does not seem logical that the server would its private key for encrypting data to be sent to the client. Else, snoopers who might have picked the public key could decrypt the data too. There is an early stage in nearly all protocols, called: key agreement where the client and server agree on a key without exchanging any of the 'private' information that it is based on. Any help on clearing up the above points would be greatly appreciated. My comments above are at a very general level. If the process was as simple as my answers, OpenSSL would not be as large a body of code as it is. ;-) Mike Thank you Regards Manish Jain invalid.poin...@gmail.com __ OpenSSL Project http://www.openssl.org User Support Mailing Listopenssl-users@openssl.org Automated List Manager majord...@openssl.org __ OpenSSL Project http://www.openssl.org User Support Mailing Listopenssl-users@openssl.org Automated List Manager majord...@openssl.org
Re: Question on OpenSSL encryption
Hello Michael/Anyone Else, Can you be kind enough to please point me to some place/URL where I can get a bit more information about how the key is negotiated upon ? I have gone through a a couple of write-ups on OpenSSL which throw light upon everything else except for this vital piece of information. Thanks Regards Manish Jain On 07-Jan-12 19:23, Michael S. Zick wrote: On Sat January 7 2012, Manish Jain wrote: Hi, I am new to OpenSSL and am trying to prepare some illustrative documentation on how it works. AFAIK, OpenSSL uses the concept of a pair of keys per host : one is a private key which is never communicated to any other host, and the other is a public key which is transmitted to the peer (the other party). The client uses the public key of the server (contained in the server's certificate) to encrypt its communication, which can only be decrypted with the server's private key. Please correct me if I am wrong. That is the essence of what happens and by that the client knows that it is communicating with the server it intended to reach (authentication). Now the question is : when the server sends data to the client, what key does it use for encryption ? The general answer is: The client and server establish a shared key for that propose early in the protocol. Does the client communicate its public key to the server (at some initial stage) which the server uses for encryption ? If the communications set up between the two requires client authentication. In many cases the client remains a stranger to the server (un-authenticated). If yes, what if the client does not have a pair of public/private keys ? The usual case for public web browsing using https and some other protocols. The client remains a stranger to the server. The question arises because it does not seem logical that the server would its private key for encrypting data to be sent to the client. Else, snoopers who might have picked the public key could decrypt the data too. There is an early stage in nearly all protocols, called: key agreement where the client and server agree on a key without exchanging any of the 'private' information that it is based on. Any help on clearing up the above points would be greatly appreciated. My comments above are at a very general level. If the process was as simple as my answers, OpenSSL would not be as large a body of code as it is. ;-) Mike Thank you Regards Manish Jain invalid.poin...@gmail.com __ OpenSSL Project http://www.openssl.org User Support Mailing Listopenssl-users@openssl.org Automated List Manager majord...@openssl.org __ OpenSSL Project http://www.openssl.org User Support Mailing Listopenssl-users@openssl.org Automated List Manager majord...@openssl.org __ OpenSSL Project http://www.openssl.org User Support Mailing Listopenssl-users@openssl.org Automated List Manager majord...@openssl.org
Re: Question on OpenSSL encryption
Hi There's quite a good description of the key negotiation here: http://technet.microsoft.com/en-us/library/cc785811%28WS.10%29.aspx Matt On 07/01/12 16:12, Manish Jain wrote: Hello Michael/Anyone Else, Can you be kind enough to please point me to some place/URL where I can get a bit more information about how the key is negotiated upon ? I have gone through a a couple of write-ups on OpenSSL which throw light upon everything else except for this vital piece of information. Thanks Regards Manish Jain On 07-Jan-12 19:23, Michael S. Zick wrote: On Sat January 7 2012, Manish Jain wrote: Hi, I am new to OpenSSL and am trying to prepare some illustrative documentation on how it works. AFAIK, OpenSSL uses the concept of a pair of keys per host : one is a private key which is never communicated to any other host, and the other is a public key which is transmitted to the peer (the other party). The client uses the public key of the server (contained in the server's certificate) to encrypt its communication, which can only be decrypted with the server's private key. Please correct me if I am wrong. That is the essence of what happens and by that the client knows that it is communicating with the server it intended to reach (authentication). Now the question is : when the server sends data to the client, what key does it use for encryption ? The general answer is: The client and server establish a shared key for that propose early in the protocol. Does the client communicate its public key to the server (at some initial stage) which the server uses for encryption ? If the communications set up between the two requires client authentication. In many cases the client remains a stranger to the server (un-authenticated). If yes, what if the client does not have a pair of public/private keys ? The usual case for public web browsing using https and some other protocols. The client remains a stranger to the server. The question arises because it does not seem logical that the server would its private key for encrypting data to be sent to the client. Else, snoopers who might have picked the public key could decrypt the data too. There is an early stage in nearly all protocols, called: key agreement where the client and server agree on a key without exchanging any of the 'private' information that it is based on. Any help on clearing up the above points would be greatly appreciated. My comments above are at a very general level. If the process was as simple as my answers, OpenSSL would not be as large a body of code as it is. ;-) Mike Thank you Regards Manish Jain invalid.poin...@gmail.com __ OpenSSL Project http://www.openssl.org User Support Mailing Listopenssl-users@openssl.org Automated List Manager majord...@openssl.org __ OpenSSL Project http://www.openssl.org User Support Mailing Listopenssl-users@openssl.org Automated List Manager majord...@openssl.org __ OpenSSL Project http://www.openssl.org User Support Mailing Listopenssl-users@openssl.org Automated List Manager majord...@openssl.org __ OpenSSL Project http://www.openssl.org User Support Mailing Listopenssl-users@openssl.org Automated List Manager majord...@openssl.org
