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author | George Hazan <george.hazan@gmail.com> | 2016-01-26 08:28:32 +0000 |
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committer | George Hazan <george.hazan@gmail.com> | 2016-01-26 08:28:32 +0000 |
commit | 2a82a9154f9d6e0b5658c82cd346051017339a1e (patch) | |
tree | 8321c2d1897d4026e68064241014eef4a57ddc9d /libs/libaxolotl/src/curve25519/ed25519/fe_isnonzero.c | |
parent | 80148955f82c205cc94f0112e0fbfe8f91bc4330 (diff) |
libaxolotl - initial commit
git-svn-id: http://svn.miranda-ng.org/main/trunk@16169 1316c22d-e87f-b044-9b9b-93d7a3e3ba9c
Diffstat (limited to 'libs/libaxolotl/src/curve25519/ed25519/fe_isnonzero.c')
-rw-r--r-- | libs/libaxolotl/src/curve25519/ed25519/fe_isnonzero.c | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/libs/libaxolotl/src/curve25519/ed25519/fe_isnonzero.c b/libs/libaxolotl/src/curve25519/ed25519/fe_isnonzero.c new file mode 100644 index 0000000000..47568001ce --- /dev/null +++ b/libs/libaxolotl/src/curve25519/ed25519/fe_isnonzero.c @@ -0,0 +1,19 @@ +#include "fe.h" +#include "crypto_verify_32.h" + +/* +return 1 if f == 0 +return 0 if f != 0 + +Preconditions: + |f| bounded by 1.1*2^26,1.1*2^25,1.1*2^26,1.1*2^25,etc. +*/ + +static const unsigned char zero[32]; + +int fe_isnonzero(const fe f) +{ + unsigned char s[32]; + fe_tobytes(s,f); + return crypto_verify_32(s,zero); +} |