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/// @file
#include "jets/q.h"
#include "jets/w.h"
#include "noun.h"
#include "urcrypt.h"
static u3_atom
_cqee_scalarmult(u3_atom a,
u3_atom b)
{
c3_y a_y[32], b_y[32], out_y[32];
if (0 != u3r_bytes_fit(32, b_y, b)) {
return u3m_bail(c3__exit);
}
c3_w met_w = u3r_met(3, a);
// scalarmult expects a_y[31] <= 127
if ( (32 < met_w) ||
( (32 == met_w) &&
(127 < u3r_byte(31, a)) )
) {
u3_noun a_recs = u3qee_recs(a);
u3r_bytes(0, 32, a_y, a_recs);
u3z(a_recs);
} else {
u3r_bytes(0, 32, a_y, a);
}
if ( (0 != urcrypt_ed_scalarmult(a_y, b_y, out_y)) ) {
// at this point, will only fail if b is bad point
return u3m_bail(c3__exit);
}
else {
return u3i_bytes(32, out_y);
}
}
u3_noun
u3wee_scalarmult(u3_noun cor)
{
u3_noun a, b;
if ( (c3n == u3r_mean(cor, u3x_sam_2, &a,
u3x_sam_3, &b, 0)) ||
(c3n == u3ud(a)) ||
(c3n == u3ud(b)) )
{
return u3m_bail(c3__exit);
} else {
return _cqee_scalarmult(a, b);
}
}
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