What does “in-house hash function” mean?
up vote
27
down vote
favorite
In security news, I faced a new term related to hash functions: it is reported that the "in-house hash function" used in IOTA platform is broken (i.e. Curl-P hash function). You can find the complete paper introducing the vulnerability here.
But I do not understand if the term of "in-house" represents a specific type of hash function? And in general, what does "in-house" mean here?
hash terminology
edited yesterday
Anders
48.4k22136157
asked yesterday
sas
479148
add a comment |
up vote
27
down vote
favorite
In security news, I faced a new term related to hash functions: it is reported that the "in-house hash function" used in IOTA platform is broken (i.e. Curl-P hash function). You can find the complete paper introducing the vulnerability here.
But I do not understand if the term of "in-house" represents a specific type of hash function? And in general, what does "in-house" mean here?
hash terminology
edited yesterday
Anders
48.4k22136157
asked yesterday
sas
479148
58
I believe the definition of "In-house hash function" is "Don't use our product, we have no idea what we're doing". (see Steffen's answer for a less cheeky response)
– Mike Ounsworth
yesterday
27
It means the same thing that "homeowner wiring" means to electricians.
– Eric Lippert
yesterday
8
@EricLippert Be fair. There's less of a chance of a catastrophic fire and loss of life with homeowner wiring.
– Nic Hartley
yesterday
1
“in-house” is a term which, if heard several times at an interview causes one to lose desire to be offered the job. Generally speaking, “in-house” can be seen as the polar opposite of “industry standard”.
– Mawg
18 hours ago
add a comment |
up vote
27
down vote
favorite
up vote
27
down vote
favorite
In security news, I faced a new term related to hash functions: it is reported that the "in-house hash function" used in IOTA platform is broken (i.e. Curl-P hash function). You can find the complete paper introducing the vulnerability here.
But I do not understand if the term of "in-house" represents a specific type of hash function? And in general, what does "in-house" mean here?
hash terminology
edited yesterday
Anders
48.4k22136157
asked yesterday
sas
479148
In security news, I faced a new term related to hash functions: it is reported that the "in-house hash function" used in IOTA platform is broken (i.e. Curl-P hash function). You can find the complete paper introducing the vulnerability here.
But I do not understand if the term of "in-house" represents a specific type of hash function? And in general, what does "in-house" mean here?
hash terminology
hash terminology
edited yesterday
Anders
48.4k22136157
asked yesterday
sas
479148
edited yesterday
Anders
48.4k22136157
asked yesterday
sas
479148
edited yesterday
Anders
48.4k22136157
edited yesterday
Anders
48.4k22136157
edited yesterday
Anders
48.4k22136157
48.4k22136157
asked yesterday
sas
479148
asked yesterday
sas
479148
asked yesterday
sas
479148
479148
58
I believe the definition of "In-house hash function" is "Don't use our product, we have no idea what we're doing". (see Steffen's answer for a less cheeky response)
– Mike Ounsworth
yesterday
27
It means the same thing that "homeowner wiring" means to electricians.
– Eric Lippert
yesterday
8
@EricLippert Be fair. There's less of a chance of a catastrophic fire and loss of life with homeowner wiring.
– Nic Hartley
yesterday
1
“in-house” is a term which, if heard several times at an interview causes one to lose desire to be offered the job. Generally speaking, “in-house” can be seen as the polar opposite of “industry standard”.
– Mawg
18 hours ago
add a comment |
58
I believe the definition of "In-house hash function" is "Don't use our product, we have no idea what we're doing". (see Steffen's answer for a less cheeky response)
– Mike Ounsworth
yesterday
27
It means the same thing that "homeowner wiring" means to electricians.
– Eric Lippert
yesterday
8
@EricLippert Be fair. There's less of a chance of a catastrophic fire and loss of life with homeowner wiring.
– Nic Hartley
yesterday
1
“in-house” is a term which, if heard several times at an interview causes one to lose desire to be offered the job. Generally speaking, “in-house” can be seen as the polar opposite of “industry standard”.
– Mawg
18 hours ago
58
58
I believe the definition of "In-house hash function" is "Don't use our product, we have no idea what we're doing". (see Steffen's answer for a less cheeky response)
– Mike Ounsworth
yesterday
I believe the definition of "In-house hash function" is "Don't use our product, we have no idea what we're doing". (see Steffen's answer for a less cheeky response)
– Mike Ounsworth
yesterday
27
27
It means the same thing that "homeowner wiring" means to electricians.
– Eric Lippert
yesterday
It means the same thing that "homeowner wiring" means to electricians.
– Eric Lippert
yesterday
8
8
@EricLippert Be fair. There's less of a chance of a catastrophic fire and loss of life with homeowner wiring.
– Nic Hartley
yesterday
@EricLippert Be fair. There's less of a chance of a catastrophic fire and loss of life with homeowner wiring.
– Nic Hartley
yesterday
1
1
“in-house” is a term which, if heard several times at an interview causes one to lose desire to be offered the job. Generally speaking, “in-house” can be seen as the polar opposite of “industry standard”.
– Mawg
18 hours ago
“in-house” is a term which, if heard several times at an interview causes one to lose desire to be offered the job. Generally speaking, “in-house” can be seen as the polar opposite of “industry standard”.
– Mawg
18 hours ago
add a comment |
2 Answers
2
active
oldest
votes
up vote
77
down vote
accepted
From the explanation of in-house in the Cambridge Directory: "Something that is done in-house is done within an organization or business by its employees rather than by other people".
Here it means developing your own hash algorithm instead of using a public one. Usually that means that it is developed by only a few people with only limited expertise in the problem area and without any public input. Thus it is very likely that the self-developed one gets eventually broken once more experts in cryptography take a look at it.
See also Why shouldn't we roll our own? and How valuable is secrecy of an algorithm?.
answered yesterday
Steffen Ullrich
111k12195258
58
Hearing "in-house" with anything security related is always a HUGE red flag.
– Marie
yesterday
5
And hearing "in-house" with anything crypto related is an even larger red flag even more often.
– NieDzejkob
yesterday
1
Also see Is my developer's home-brew password security right or wrong, and why?, although I suspect Dave's algorithm was much, much worse than IOTA's.
– jpmc26
yesterday
In short, in this context, "in-house" means "trouble"!
– Muzer
21 hours ago
add a comment |
up vote
-13
down vote
I agree with the answer given an hour before this one about in-house meaning, "non-standard and probably not very sophisticated or rugged." There may still be one argument in favor of using an in-house hash. That is, it may be different enough from the standard ones out there that a hacker may decide it is too much work to figure out how to reverse engineer it. Even if you accept this argument, this sort of do-it-yourself approach should only ever be used to protect very low-value data.
answered yesterday
Peter Knibbe
15
New contributor
Peter Knibbe is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
26
This line of reasoning - relying on an attacker not knowing the implementation details and hoping that they won't find out - is named "Security by Obscurity". Since this is only a slowdown, rarely really a barrier, it is generally frowned upon and strongly recommended against. One area where it still does make sense is if your assets drop rapidly in worth in a short time (days to months) and an attack after one year is much less of an impact. Most game and movie DRM / copy protection schemes fall under this category.
– Zefiro
yesterday
6
It's almost a trope at this point that whenever a "why is X bad?" question is posted, there will be an answer that says, paraphrasing, "well it's not that bad, because at least the attackers won't know how your version works". In other words, an appeal to Security by Obscurity. And yes, I get that this answer doesn't reject the premise, but others have done.
– Tom W
yesterday
1
@Zefiro: There is a difference between "hoping that an attacker doesn't find out", and considering the cost/benefit ratios for possible attacks. To be sure, the risk of a popular encryption or hashing scheme being defeated may be slight, despite the level of research into attacks on them, but the probability of a scheme no prospective attackers would care about being defeated might be even lower.
– supercat
yesterday
2
@Zefiro This reasoning is not about an attacker not knowing the implementation details. I think you need to read it again. It's about an attacker not having sufficient motivation to bother trying to break the algorithm. (It's still wrong, but not because it's security by obscurity, because it's not security at all. The problem is that you're very likely to drastically overestimate how much security you actually have, and that's exactly what happened here.)
– David Schwartz
yesterday
2
@supercat The problem is that normally, it's just security by obscurity. If you, say, shuffle an otherwise secure hash before storing (and unshuffle on retrieval and comparison), sure, that does extremely little for security, but it doesn't harm it. If all that's done is the shuffle, that's... very bad. And it's the latter case that's normally done, not the former. So people say "don't ever use it", because that's a good rule of thumb, and once you're experienced enough to know the difference, you're experienced enough to know when to ignore rules of thumb.
– Nic Hartley
yesterday
|
show 6 more comments
2 Answers
2
active
oldest
votes
2 Answers
2
active
oldest
votes
active
oldest
votes
active
oldest
votes
up vote
77
down vote
accepted
From the explanation of in-house in the Cambridge Directory: "Something that is done in-house is done within an organization or business by its employees rather than by other people".
Here it means developing your own hash algorithm instead of using a public one. Usually that means that it is developed by only a few people with only limited expertise in the problem area and without any public input. Thus it is very likely that the self-developed one gets eventually broken once more experts in cryptography take a look at it.
See also Why shouldn't we roll our own? and How valuable is secrecy of an algorithm?.
answered yesterday
Steffen Ullrich
111k12195258
58
Hearing "in-house" with anything security related is always a HUGE red flag.
– Marie
yesterday
5
And hearing "in-house" with anything crypto related is an even larger red flag even more often.
– NieDzejkob
yesterday
1
Also see Is my developer's home-brew password security right or wrong, and why?, although I suspect Dave's algorithm was much, much worse than IOTA's.
– jpmc26
yesterday
In short, in this context, "in-house" means "trouble"!
– Muzer
21 hours ago
add a comment |
up vote
77
down vote
accepted
From the explanation of in-house in the Cambridge Directory: "Something that is done in-house is done within an organization or business by its employees rather than by other people".
Here it means developing your own hash algorithm instead of using a public one. Usually that means that it is developed by only a few people with only limited expertise in the problem area and without any public input. Thus it is very likely that the self-developed one gets eventually broken once more experts in cryptography take a look at it.
See also Why shouldn't we roll our own? and How valuable is secrecy of an algorithm?.
answered yesterday
Steffen Ullrich
111k12195258
58
Hearing "in-house" with anything security related is always a HUGE red flag.
– Marie
yesterday
5
And hearing "in-house" with anything crypto related is an even larger red flag even more often.
– NieDzejkob
yesterday
1
Also see Is my developer's home-brew password security right or wrong, and why?, although I suspect Dave's algorithm was much, much worse than IOTA's.
– jpmc26
yesterday
In short, in this context, "in-house" means "trouble"!
– Muzer
21 hours ago
add a comment |
up vote
77
down vote
accepted
up vote
77
down vote
accepted
From the explanation of in-house in the Cambridge Directory: "Something that is done in-house is done within an organization or business by its employees rather than by other people".
Here it means developing your own hash algorithm instead of using a public one. Usually that means that it is developed by only a few people with only limited expertise in the problem area and without any public input. Thus it is very likely that the self-developed one gets eventually broken once more experts in cryptography take a look at it.
See also Why shouldn't we roll our own? and How valuable is secrecy of an algorithm?.
answered yesterday
Steffen Ullrich
111k12195258
From the explanation of in-house in the Cambridge Directory: "Something that is done in-house is done within an organization or business by its employees rather than by other people".
Here it means developing your own hash algorithm instead of using a public one. Usually that means that it is developed by only a few people with only limited expertise in the problem area and without any public input. Thus it is very likely that the self-developed one gets eventually broken once more experts in cryptography take a look at it.
See also Why shouldn't we roll our own? and How valuable is secrecy of an algorithm?.
answered yesterday
Steffen Ullrich
111k12195258
edited yesterday
answered yesterday
Steffen Ullrich
111k12195258
answered yesterday
Steffen Ullrich
111k12195258
answered yesterday
Steffen Ullrich
111k12195258
111k12195258
58
Hearing "in-house" with anything security related is always a HUGE red flag.
– Marie
yesterday
5
And hearing "in-house" with anything crypto related is an even larger red flag even more often.
– NieDzejkob
yesterday
1
Also see Is my developer's home-brew password security right or wrong, and why?, although I suspect Dave's algorithm was much, much worse than IOTA's.
– jpmc26
yesterday
In short, in this context, "in-house" means "trouble"!
– Muzer
21 hours ago
add a comment |
58
Hearing "in-house" with anything security related is always a HUGE red flag.
– Marie
yesterday
5
And hearing "in-house" with anything crypto related is an even larger red flag even more often.
– NieDzejkob
yesterday
1
Also see Is my developer's home-brew password security right or wrong, and why?, although I suspect Dave's algorithm was much, much worse than IOTA's.
– jpmc26
yesterday
In short, in this context, "in-house" means "trouble"!
– Muzer
21 hours ago
58
58
Hearing "in-house" with anything security related is always a HUGE red flag.
– Marie
yesterday
Hearing "in-house" with anything security related is always a HUGE red flag.
– Marie
yesterday
5
5
And hearing "in-house" with anything crypto related is an even larger red flag even more often.
– NieDzejkob
yesterday
And hearing "in-house" with anything crypto related is an even larger red flag even more often.
– NieDzejkob
yesterday
1
1
Also see Is my developer's home-brew password security right or wrong, and why?, although I suspect Dave's algorithm was much, much worse than IOTA's.
– jpmc26
yesterday
Also see Is my developer's home-brew password security right or wrong, and why?, although I suspect Dave's algorithm was much, much worse than IOTA's.
– jpmc26
yesterday
In short, in this context, "in-house" means "trouble"!
– Muzer
21 hours ago
In short, in this context, "in-house" means "trouble"!
– Muzer
21 hours ago
add a comment |
up vote
-13
down vote
I agree with the answer given an hour before this one about in-house meaning, "non-standard and probably not very sophisticated or rugged." There may still be one argument in favor of using an in-house hash. That is, it may be different enough from the standard ones out there that a hacker may decide it is too much work to figure out how to reverse engineer it. Even if you accept this argument, this sort of do-it-yourself approach should only ever be used to protect very low-value data.
answered yesterday
Peter Knibbe
15
New contributor
Peter Knibbe is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
26
This line of reasoning - relying on an attacker not knowing the implementation details and hoping that they won't find out - is named "Security by Obscurity". Since this is only a slowdown, rarely really a barrier, it is generally frowned upon and strongly recommended against. One area where it still does make sense is if your assets drop rapidly in worth in a short time (days to months) and an attack after one year is much less of an impact. Most game and movie DRM / copy protection schemes fall under this category.
– Zefiro
yesterday
6
It's almost a trope at this point that whenever a "why is X bad?" question is posted, there will be an answer that says, paraphrasing, "well it's not that bad, because at least the attackers won't know how your version works". In other words, an appeal to Security by Obscurity. And yes, I get that this answer doesn't reject the premise, but others have done.
– Tom W
yesterday
1
@Zefiro: There is a difference between "hoping that an attacker doesn't find out", and considering the cost/benefit ratios for possible attacks. To be sure, the risk of a popular encryption or hashing scheme being defeated may be slight, despite the level of research into attacks on them, but the probability of a scheme no prospective attackers would care about being defeated might be even lower.
– supercat
yesterday
2
@Zefiro This reasoning is not about an attacker not knowing the implementation details. I think you need to read it again. It's about an attacker not having sufficient motivation to bother trying to break the algorithm. (It's still wrong, but not because it's security by obscurity, because it's not security at all. The problem is that you're very likely to drastically overestimate how much security you actually have, and that's exactly what happened here.)
– David Schwartz
yesterday
2
@supercat The problem is that normally, it's just security by obscurity. If you, say, shuffle an otherwise secure hash before storing (and unshuffle on retrieval and comparison), sure, that does extremely little for security, but it doesn't harm it. If all that's done is the shuffle, that's... very bad. And it's the latter case that's normally done, not the former. So people say "don't ever use it", because that's a good rule of thumb, and once you're experienced enough to know the difference, you're experienced enough to know when to ignore rules of thumb.
– Nic Hartley
yesterday
|
show 6 more comments
up vote
-13
down vote
I agree with the answer given an hour before this one about in-house meaning, "non-standard and probably not very sophisticated or rugged." There may still be one argument in favor of using an in-house hash. That is, it may be different enough from the standard ones out there that a hacker may decide it is too much work to figure out how to reverse engineer it. Even if you accept this argument, this sort of do-it-yourself approach should only ever be used to protect very low-value data.
answered yesterday
Peter Knibbe
15
New contributor
Peter Knibbe is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
26
This line of reasoning - relying on an attacker not knowing the implementation details and hoping that they won't find out - is named "Security by Obscurity". Since this is only a slowdown, rarely really a barrier, it is generally frowned upon and strongly recommended against. One area where it still does make sense is if your assets drop rapidly in worth in a short time (days to months) and an attack after one year is much less of an impact. Most game and movie DRM / copy protection schemes fall under this category.
– Zefiro
yesterday
6
It's almost a trope at this point that whenever a "why is X bad?" question is posted, there will be an answer that says, paraphrasing, "well it's not that bad, because at least the attackers won't know how your version works". In other words, an appeal to Security by Obscurity. And yes, I get that this answer doesn't reject the premise, but others have done.
– Tom W
yesterday
1
@Zefiro: There is a difference between "hoping that an attacker doesn't find out", and considering the cost/benefit ratios for possible attacks. To be sure, the risk of a popular encryption or hashing scheme being defeated may be slight, despite the level of research into attacks on them, but the probability of a scheme no prospective attackers would care about being defeated might be even lower.
– supercat
yesterday
2
@Zefiro This reasoning is not about an attacker not knowing the implementation details. I think you need to read it again. It's about an attacker not having sufficient motivation to bother trying to break the algorithm. (It's still wrong, but not because it's security by obscurity, because it's not security at all. The problem is that you're very likely to drastically overestimate how much security you actually have, and that's exactly what happened here.)
– David Schwartz
yesterday
2
@supercat The problem is that normally, it's just security by obscurity. If you, say, shuffle an otherwise secure hash before storing (and unshuffle on retrieval and comparison), sure, that does extremely little for security, but it doesn't harm it. If all that's done is the shuffle, that's... very bad. And it's the latter case that's normally done, not the former. So people say "don't ever use it", because that's a good rule of thumb, and once you're experienced enough to know the difference, you're experienced enough to know when to ignore rules of thumb.
– Nic Hartley
yesterday
|
show 6 more comments
up vote
-13
down vote
up vote
-13
down vote
I agree with the answer given an hour before this one about in-house meaning, "non-standard and probably not very sophisticated or rugged." There may still be one argument in favor of using an in-house hash. That is, it may be different enough from the standard ones out there that a hacker may decide it is too much work to figure out how to reverse engineer it. Even if you accept this argument, this sort of do-it-yourself approach should only ever be used to protect very low-value data.
answered yesterday
Peter Knibbe
15
New contributor
Peter Knibbe is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
I agree with the answer given an hour before this one about in-house meaning, "non-standard and probably not very sophisticated or rugged." There may still be one argument in favor of using an in-house hash. That is, it may be different enough from the standard ones out there that a hacker may decide it is too much work to figure out how to reverse engineer it. Even if you accept this argument, this sort of do-it-yourself approach should only ever be used to protect very low-value data.
answered yesterday
Peter Knibbe
15
New contributor
Peter Knibbe is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
answered yesterday
Peter Knibbe
15
New contributor
Peter Knibbe is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
answered yesterday
Peter Knibbe
15
answered yesterday
Peter Knibbe
15
15
New contributor
Peter Knibbe is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
New contributor
Peter Knibbe is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
Peter Knibbe is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
26
This line of reasoning - relying on an attacker not knowing the implementation details and hoping that they won't find out - is named "Security by Obscurity". Since this is only a slowdown, rarely really a barrier, it is generally frowned upon and strongly recommended against. One area where it still does make sense is if your assets drop rapidly in worth in a short time (days to months) and an attack after one year is much less of an impact. Most game and movie DRM / copy protection schemes fall under this category.
– Zefiro
yesterday
6
It's almost a trope at this point that whenever a "why is X bad?" question is posted, there will be an answer that says, paraphrasing, "well it's not that bad, because at least the attackers won't know how your version works". In other words, an appeal to Security by Obscurity. And yes, I get that this answer doesn't reject the premise, but others have done.
– Tom W
yesterday
1
@Zefiro: There is a difference between "hoping that an attacker doesn't find out", and considering the cost/benefit ratios for possible attacks. To be sure, the risk of a popular encryption or hashing scheme being defeated may be slight, despite the level of research into attacks on them, but the probability of a scheme no prospective attackers would care about being defeated might be even lower.
– supercat
yesterday
2
@Zefiro This reasoning is not about an attacker not knowing the implementation details. I think you need to read it again. It's about an attacker not having sufficient motivation to bother trying to break the algorithm. (It's still wrong, but not because it's security by obscurity, because it's not security at all. The problem is that you're very likely to drastically overestimate how much security you actually have, and that's exactly what happened here.)
– David Schwartz
yesterday
2
@supercat The problem is that normally, it's just security by obscurity. If you, say, shuffle an otherwise secure hash before storing (and unshuffle on retrieval and comparison), sure, that does extremely little for security, but it doesn't harm it. If all that's done is the shuffle, that's... very bad. And it's the latter case that's normally done, not the former. So people say "don't ever use it", because that's a good rule of thumb, and once you're experienced enough to know the difference, you're experienced enough to know when to ignore rules of thumb.
– Nic Hartley
yesterday
|
show 6 more comments
26
This line of reasoning - relying on an attacker not knowing the implementation details and hoping that they won't find out - is named "Security by Obscurity". Since this is only a slowdown, rarely really a barrier, it is generally frowned upon and strongly recommended against. One area where it still does make sense is if your assets drop rapidly in worth in a short time (days to months) and an attack after one year is much less of an impact. Most game and movie DRM / copy protection schemes fall under this category.
– Zefiro
yesterday
6
It's almost a trope at this point that whenever a "why is X bad?" question is posted, there will be an answer that says, paraphrasing, "well it's not that bad, because at least the attackers won't know how your version works". In other words, an appeal to Security by Obscurity. And yes, I get that this answer doesn't reject the premise, but others have done.
– Tom W
yesterday
1
@Zefiro: There is a difference between "hoping that an attacker doesn't find out", and considering the cost/benefit ratios for possible attacks. To be sure, the risk of a popular encryption or hashing scheme being defeated may be slight, despite the level of research into attacks on them, but the probability of a scheme no prospective attackers would care about being defeated might be even lower.
– supercat
yesterday
2
@Zefiro This reasoning is not about an attacker not knowing the implementation details. I think you need to read it again. It's about an attacker not having sufficient motivation to bother trying to break the algorithm. (It's still wrong, but not because it's security by obscurity, because it's not security at all. The problem is that you're very likely to drastically overestimate how much security you actually have, and that's exactly what happened here.)
– David Schwartz
yesterday
2
@supercat The problem is that normally, it's just security by obscurity. If you, say, shuffle an otherwise secure hash before storing (and unshuffle on retrieval and comparison), sure, that does extremely little for security, but it doesn't harm it. If all that's done is the shuffle, that's... very bad. And it's the latter case that's normally done, not the former. So people say "don't ever use it", because that's a good rule of thumb, and once you're experienced enough to know the difference, you're experienced enough to know when to ignore rules of thumb.
– Nic Hartley
yesterday
26
26
This line of reasoning - relying on an attacker not knowing the implementation details and hoping that they won't find out - is named "Security by Obscurity". Since this is only a slowdown, rarely really a barrier, it is generally frowned upon and strongly recommended against. One area where it still does make sense is if your assets drop rapidly in worth in a short time (days to months) and an attack after one year is much less of an impact. Most game and movie DRM / copy protection schemes fall under this category.
– Zefiro
yesterday
This line of reasoning - relying on an attacker not knowing the implementation details and hoping that they won't find out - is named "Security by Obscurity". Since this is only a slowdown, rarely really a barrier, it is generally frowned upon and strongly recommended against. One area where it still does make sense is if your assets drop rapidly in worth in a short time (days to months) and an attack after one year is much less of an impact. Most game and movie DRM / copy protection schemes fall under this category.
– Zefiro
yesterday
6
6
It's almost a trope at this point that whenever a "why is X bad?" question is posted, there will be an answer that says, paraphrasing, "well it's not that bad, because at least the attackers won't know how your version works". In other words, an appeal to Security by Obscurity. And yes, I get that this answer doesn't reject the premise, but others have done.
– Tom W
yesterday
It's almost a trope at this point that whenever a "why is X bad?" question is posted, there will be an answer that says, paraphrasing, "well it's not that bad, because at least the attackers won't know how your version works". In other words, an appeal to Security by Obscurity. And yes, I get that this answer doesn't reject the premise, but others have done.
– Tom W
yesterday
1
1
@Zefiro: There is a difference between "hoping that an attacker doesn't find out", and considering the cost/benefit ratios for possible attacks. To be sure, the risk of a popular encryption or hashing scheme being defeated may be slight, despite the level of research into attacks on them, but the probability of a scheme no prospective attackers would care about being defeated might be even lower.
– supercat
yesterday
@Zefiro: There is a difference between "hoping that an attacker doesn't find out", and considering the cost/benefit ratios for possible attacks. To be sure, the risk of a popular encryption or hashing scheme being defeated may be slight, despite the level of research into attacks on them, but the probability of a scheme no prospective attackers would care about being defeated might be even lower.
– supercat
yesterday
2
2
@Zefiro This reasoning is not about an attacker not knowing the implementation details. I think you need to read it again. It's about an attacker not having sufficient motivation to bother trying to break the algorithm. (It's still wrong, but not because it's security by obscurity, because it's not security at all. The problem is that you're very likely to drastically overestimate how much security you actually have, and that's exactly what happened here.)
– David Schwartz
yesterday
@Zefiro This reasoning is not about an attacker not knowing the implementation details. I think you need to read it again. It's about an attacker not having sufficient motivation to bother trying to break the algorithm. (It's still wrong, but not because it's security by obscurity, because it's not security at all. The problem is that you're very likely to drastically overestimate how much security you actually have, and that's exactly what happened here.)
– David Schwartz
yesterday
2
2
@supercat The problem is that normally, it's just security by obscurity. If you, say, shuffle an otherwise secure hash before storing (and unshuffle on retrieval and comparison), sure, that does extremely little for security, but it doesn't harm it. If all that's done is the shuffle, that's... very bad. And it's the latter case that's normally done, not the former. So people say "don't ever use it", because that's a good rule of thumb, and once you're experienced enough to know the difference, you're experienced enough to know when to ignore rules of thumb.
– Nic Hartley
yesterday
@supercat The problem is that normally, it's just security by obscurity. If you, say, shuffle an otherwise secure hash before storing (and unshuffle on retrieval and comparison), sure, that does extremely little for security, but it doesn't harm it. If all that's done is the shuffle, that's... very bad. And it's the latter case that's normally done, not the former. So people say "don't ever use it", because that's a good rule of thumb, and once you're experienced enough to know the difference, you're experienced enough to know when to ignore rules of thumb.
– Nic Hartley
yesterday
|
show 6 more comments
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fsecurity.stackexchange.com%2fquestions%2f198134%2fwhat-does-in-house-hash-function-mean%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
58
I believe the definition of "In-house hash function" is "Don't use our product, we have no idea what we're doing". (see Steffen's answer for a less cheeky response)
– Mike Ounsworth
yesterday
27
It means the same thing that "homeowner wiring" means to electricians.
– Eric Lippert
yesterday
8
@EricLippert Be fair. There's less of a chance of a catastrophic fire and loss of life with homeowner wiring.
– Nic Hartley
yesterday
1
“in-house” is a term which, if heard several times at an interview causes one to lose desire to be offered the job. Generally speaking, “in-house” can be seen as the polar opposite of “industry standard”.
– Mawg
18 hours ago