Re: [PATCH 1/3] add collision-detecting sha1 implementation

2017-02-23 Thread Jeff King 
On Thu, Feb 23, 2017 at 04:12:01PM -0800, Linus Torvalds wrote:

> On Thu, Feb 23, 2017 at 4:01 PM, Jeff King  wrote:
> >
> > You know, I didn't even look at the LICENSE file, since it said MIT and
> > had a link here. It would be trivial to copy it over, too, of course.
> 
> You should do it. It's just good to be careful and clear with
> licenses, and the license text does require that the copyright notice
> and permission file should be included in copies.
> 
> My patch did it. "Pats self on head".

And that's why yours crossed the 100K barrier. :)

But yeah, I agree it is better to be safe (and that's we should contact
the authors). I'll point them out-of-band to this thread, and cc them if
it ends up being re-rolled.

-Peff

Re: [PATCH 1/3] add collision-detecting sha1 implementation

2017-02-23 Thread Linus Torvalds 
On Thu, Feb 23, 2017 at 4:01 PM, Jeff King  wrote:
>
> You know, I didn't even look at the LICENSE file, since it said MIT and
> had a link here. It would be trivial to copy it over, too, of course.

You should do it. It's just good to be careful and clear with
licenses, and the license text does require that the copyright notice
and permission file should be included in copies.

My patch did it. "Pats self on head".

 Linus

PS. And just to be polite, we should probably also just cc at least
Marc Stevens and Dan Shumow if we take that patch further. Their email
addresses are in the that LICENSE.txt file.

Re: [PATCH 1/3] add collision-detecting sha1 implementation

2017-02-23 Thread Jeff King 
On Thu, Feb 23, 2017 at 03:15:11PM -0800, Stefan Beller wrote:

> On Thu, Feb 23, 2017 at 3:05 PM, Jeff King  wrote:
> 
> > +* Copyright 2017 Marc Stevens , Dan Shumow 
> > (dan...@microsoft.com)
> > +* Distributed under the MIT Software License.
> > +* See accompanying file LICENSE.txt or copy at
> 
> The accompanying LICENSE file did not make it into this patch,
> that is more specialized/verbose than the one at
> https://opensource.org/licenses/MIT
> w.r.t. copyright notice requirement.

You know, I didn't even look at the LICENSE file, since it said MIT and
had a link here. It would be trivial to copy it over, too, of course.

> Apart from that MIT seems to be compatible with GPL
> according to the FSF, though IANAL.

Yeah, that's always been my understanding.

-Peff

Re: [PATCH 1/3] add collision-detecting sha1 implementation

2017-02-23 Thread Stefan Beller 
On Thu, Feb 23, 2017 at 3:05 PM, Jeff King  wrote:

> +* Copyright 2017 Marc Stevens , Dan Shumow 
> (dan...@microsoft.com)
> +* Distributed under the MIT Software License.
> +* See accompanying file LICENSE.txt or copy at

The accompanying LICENSE file did not make it into this patch,
that is more specialized/verbose than the one at
https://opensource.org/licenses/MIT
w.r.t. copyright notice requirement.

Apart from that MIT seems to be compatible with GPL
according to the FSF, though IANAL.

[PATCH 1/3] add collision-detecting sha1 implementation

2017-02-23 Thread Jeff King 
This is pulled straight from:

  https://github.com/cr-marcstevens/sha1collisiondetection

with no modifications yet (though I've pulled in only the
subset of files necessary for Git to use).

Signed-off-by: Jeff King 
---
 sha1dc/sha1.c  | 1146 
 sha1dc/sha1.h  |   94 +
 sha1dc/ubc_check.c |  361 +
 sha1dc/ubc_check.h |   35 ++
 4 files changed, 1636 insertions(+)
 create mode 100644 sha1dc/sha1.c
 create mode 100644 sha1dc/sha1.h
 create mode 100644 sha1dc/ubc_check.c
 create mode 100644 sha1dc/ubc_check.h

diff --git a/sha1dc/sha1.c b/sha1dc/sha1.c
new file mode 100644
index 0..ed2010911
--- /dev/null
+++ b/sha1dc/sha1.c
@@ -0,0 +1,1146 @@
+/***
+* Copyright 2017 Marc Stevens , Dan Shumow 
(dan...@microsoft.com) 
+* Distributed under the MIT Software License.
+* See accompanying file LICENSE.txt or copy at
+* https://opensource.org/licenses/MIT
+***/
+
+#include 
+#include 
+#include 
+
+#include "sha1.h"
+#include "ubc_check.h"
+
+#define rotate_right(x,n) (((x)>>(n))|((x)<<(32-(n
+#define rotate_left(x,n)  (((x)<<(n))|((x)>>(32-(n
+
+#define sha1_f1(b,c,d) ((d)^((b)&((c)^(d
+#define sha1_f2(b,c,d) ((b)^(c)^(d))
+#define sha1_f3(b,c,d) (((b) & ((c)|(d))) | ((c)&(d)))
+#define sha1_f4(b,c,d) ((b)^(c)^(d))
+
+#define HASHCLASH_SHA1COMPRESS_ROUND1_STEP(a, b, c, d, e, m, t) \
+   { e += rotate_left(a, 5) + sha1_f1(b,c,d) + 0x5A827999 + m[t]; b = 
rotate_left(b, 30); }
+#define HASHCLASH_SHA1COMPRESS_ROUND2_STEP(a, b, c, d, e, m, t) \
+   { e += rotate_left(a, 5) + sha1_f2(b,c,d) + 0x6ED9EBA1 + m[t]; b = 
rotate_left(b, 30); }
+#define HASHCLASH_SHA1COMPRESS_ROUND3_STEP(a, b, c, d, e, m, t) \
+   { e += rotate_left(a, 5) + sha1_f3(b,c,d) + 0x8F1BBCDC + m[t]; b = 
rotate_left(b, 30); }
+#define HASHCLASH_SHA1COMPRESS_ROUND4_STEP(a, b, c, d, e, m, t) \
+   { e += rotate_left(a, 5) + sha1_f4(b,c,d) + 0xCA62C1D6 + m[t]; b = 
rotate_left(b, 30); }
+
+#define HASHCLASH_SHA1COMPRESS_ROUND1_STEP_BW(a, b, c, d, e, m, t) \
+   { b = rotate_right(b, 30); e -= rotate_left(a, 5) + sha1_f1(b,c,d) + 
0x5A827999 + m[t]; }
+#define HASHCLASH_SHA1COMPRESS_ROUND2_STEP_BW(a, b, c, d, e, m, t) \
+   { b = rotate_right(b, 30); e -= rotate_left(a, 5) + sha1_f2(b,c,d) + 
0x6ED9EBA1 + m[t]; }
+#define HASHCLASH_SHA1COMPRESS_ROUND3_STEP_BW(a, b, c, d, e, m, t) \
+   { b = rotate_right(b, 30); e -= rotate_left(a, 5) + sha1_f3(b,c,d) + 
0x8F1BBCDC + m[t]; }
+#define HASHCLASH_SHA1COMPRESS_ROUND4_STEP_BW(a, b, c, d, e, m, t) \
+   { b = rotate_right(b, 30); e -= rotate_left(a, 5) + sha1_f4(b,c,d) + 
0xCA62C1D6 + m[t]; }
+
+#define SHA1_STORE_STATE(i) states[i][0] = a; states[i][1] = b; states[i][2] = 
c; states[i][3] = d; states[i][4] = e;
+
+
+
+void sha1_message_expansion(uint32_t W[80])
+{
+   for (unsigned i = 16; i < 80; ++i)
+   W[i] = rotate_left(W[i - 3] ^ W[i - 8] ^ W[i - 14] ^ W[i - 16], 
1);
+}
+
+void sha1_compression(uint32_t ihv[5], const uint32_t m[16])
+{
+   uint32_t W[80];
+
+   memcpy(W, m, 16 * 4);
+   for (unsigned i = 16; i < 80; ++i)
+   W[i] = rotate_left(W[i - 3] ^ W[i - 8] ^ W[i - 14] ^ W[i - 16], 
1);
+
+   uint32_t a = ihv[0], b = ihv[1], c = ihv[2], d = ihv[3], e = ihv[4];
+
+   HASHCLASH_SHA1COMPRESS_ROUND1_STEP(a, b, c, d, e, W, 0);
+   HASHCLASH_SHA1COMPRESS_ROUND1_STEP(e, a, b, c, d, W, 1);
+   HASHCLASH_SHA1COMPRESS_ROUND1_STEP(d, e, a, b, c, W, 2);
+   HASHCLASH_SHA1COMPRESS_ROUND1_STEP(c, d, e, a, b, W, 3);
+   HASHCLASH_SHA1COMPRESS_ROUND1_STEP(b, c, d, e, a, W, 4);
+   HASHCLASH_SHA1COMPRESS_ROUND1_STEP(a, b, c, d, e, W, 5);
+   HASHCLASH_SHA1COMPRESS_ROUND1_STEP(e, a, b, c, d, W, 6);
+   HASHCLASH_SHA1COMPRESS_ROUND1_STEP(d, e, a, b, c, W, 7);
+   HASHCLASH_SHA1COMPRESS_ROUND1_STEP(c, d, e, a, b, W, 8);
+   HASHCLASH_SHA1COMPRESS_ROUND1_STEP(b, c, d, e, a, W, 9);
+   HASHCLASH_SHA1COMPRESS_ROUND1_STEP(a, b, c, d, e, W, 10);
+   HASHCLASH_SHA1COMPRESS_ROUND1_STEP(e, a, b, c, d, W, 11);
+   HASHCLASH_SHA1COMPRESS_ROUND1_STEP(d, e, a, b, c, W, 12);
+   HASHCLASH_SHA1COMPRESS_ROUND1_STEP(c, d, e, a, b, W, 13);
+   HASHCLASH_SHA1COMPRESS_ROUND1_STEP(b, c, d, e, a, W, 14);
+   HASHCLASH_SHA1COMPRESS_ROUND1_STEP(a, b, c, d, e, W, 15);
+   HASHCLASH_SHA1COMPRESS_ROUND1_STEP(e, a, b, c, d, W, 16);
+   HASHCLASH_SHA1COMPRESS_ROUND1_STEP(d, e, a, b, c, W, 17);
+   HASHCLASH_SHA1COMPRESS_ROUND1_STEP(c, d, e, a, b, W, 18);
+   HASHCLASH_SHA1COMPRESS_ROUND1_STEP(b, c, d, e, a, W, 19);
+
+   HASHCLASH_SHA1COMPRESS_ROUND2_STEP(a, b, c, d, e, W, 20);
+   HASHCLASH_SHA1COMPRESS_ROUND2_STEP(e, a, b, c, d, W, 21);
+   HASHCLASH_SHA1COMPRESS_ROUND2_STEP(d, e, a, b, c, W, 22);
+   HASHCLASH_SHA1COMPRESS_ROUND2_STEP(c, d, e, a, b, W, 23);
+   HASHCLASH_SHA1COMPRESS_ROUND2_STEP(b, c, d, e, a, W, 24);
+   HASHCLASH_SHA1COMPRESS_ROUND2_STEP(a, b, c