X-Git-Url: https://git.openssl.org/gitweb/?p=openssl.git;a=blobdiff_plain;f=doc%2Fcrypto%2FBN_mod_mul_montgomery.pod;h=6b16351b92e4bd67967762e3f0de7858c5a620e8;hp=f237f7264ed86bd7cd3e37dc1fef5ff46f8b4869;hb=2d780dfd81b47107bd2f2eaa4206994d0fc0ab42;hpb=6c2c3e9ba9146ef8c9b1fd2b660357b657706969

diff --git a/doc/crypto/BN_mod_mul_montgomery.pod b/doc/crypto/BN_mod_mul_montgomery.pod
index f237f7264e..6b16351b92 100644
--- a/doc/crypto/BN_mod_mul_montgomery.pod
+++ b/doc/crypto/BN_mod_mul_montgomery.pod
@@ -36,29 +36,29 @@ using the same modulus.
 BN_MONT_CTX_new() allocates and initializes a B<BN_MONT_CTX> structure.
 BN_MONT_CTX_init() initializes an existing uninitialized B<BN_MONT_CTX>.
 
-BN_MONT_CTX_set() sets up the B<mont> structure from the modulus B<m>
+BN_MONT_CTX_set() sets up the I<mont> structure from the modulus I<m>
 by precomputing its inverse and a value R.
 
-BN_MONT_CTX_copy() copies the B<N_MONT_CTX> B<from> to B<to>.
+BN_MONT_CTX_copy() copies the B<BN_MONT_CTX> I<from> to I<to>.
 
 BN_MONT_CTX_free() frees the components of the B<BN_MONT_CTX>, and, if
 it was created by BN_MONT_CTX_new(), also the structure itself.
 
-BN_mod_mul_montgomery() computes Mont(B<a>,B<b>):=B<a>*B<b>*R^-1 and places
-the result in B<r>.
+BN_mod_mul_montgomery() computes Mont(I<a>,I<b>):=I<a>*I<b>*R^-1 and places
+the result in I<r>.
 
-BN_from_montgomery() performs the Montgomery reduction B<r> = B<a>*R^-1.
+BN_from_montgomery() performs the Montgomery reduction I<r> = I<a>*R^-1.
 
-BN_to_montgomery() computes Mont(B<a>,R^2).
+BN_to_montgomery() computes Mont(I<a>,R^2), i.e. I<a>*R.
+Note that I<a> must be non-negative and smaller than the modulus.
 
-For all functions, B<ctx> is a previously allocated B<BN_CTX> used for
+For all functions, I<ctx> is a previously allocated B<BN_CTX> used for
 temporary variables.
 
 The B<BN_MONT_CTX> structure is defined as follows:
 
  typedef struct bn_mont_ctx_st
         {
-        int use_word;   /* 0 for word form, 1 for bignum form */
         int ri;         /* number of bits in R */
         BIGNUM RR;      /* R^2 (used to convert to Montgomery form) */
         BIGNUM N;       /* The modulus */
@@ -80,9 +80,14 @@ BN_MONT_CTX_init() and BN_MONT_CTX_free() have no return values.
 For the other functions, 1 is returned for success, 0 on error.
 The error codes can be obtained by L<ERR_get_error(3)|ERR_get_error(3)>.
 
+=head1 WARNING
+
+The inputs must be reduced modulo B<m>, otherwise the result will be
+outside the expected range.
+
 =head1 SEE ALSO
 
-L<bn(3)|bn(3)>, L<err(3)|err(3)>, L<BN_add(3)|BN_add(3)>,
+L<bn(3)|bn(3)>, L<ERR_get_error(3)|ERR_get_error(3)>, L<BN_add(3)|BN_add(3)>,
 L<BN_CTX_new(3)|BN_CTX_new(3)>
 
 =head1 HISTORY