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authorBodo Möller <bodo@openssl.org>2000-01-30 02:23:03 +0000
committerBodo Möller <bodo@openssl.org>2000-01-30 02:23:03 +0000
commita87030a1edf0e4c6d601895f810b2d0da84ee10a (patch)
tree398075a9540e68b2dc417a80ac83fe13e5253958 /doc
parent15701211b57b63f1f91a9c3781ea91c019b1dc1d (diff)
downloadopenssl-a87030a1edf0e4c6d601895f810b2d0da84ee10a.tar.gz
Make DSA_generate_parameters, and fix a couple of bug
(including another problem in the s3_srvr.c state machine).
Diffstat (limited to 'doc')
-rw-r--r--doc/crypto/DSA_generate_parameters.pod39
1 files changed, 23 insertions, 16 deletions
diff --git a/doc/crypto/DSA_generate_parameters.pod b/doc/crypto/DSA_generate_parameters.pod
index 1058c5eb44..bae4e1b560 100644
--- a/doc/crypto/DSA_generate_parameters.pod
+++ b/doc/crypto/DSA_generate_parameters.pod
@@ -20,14 +20,14 @@ for use in the DSA.
B<bits> is the length of the prime to be generated; the DSS allows a
maximum of 1024 bits.
-If B<seed> is NULL or B<seed_len> E<lt> 20, the primes will be
+If B<seed> is B<NULL> or B<seed_len> E<lt> 20, the primes will be
generated at random. Otherwise, the seed is used to generate
them. If the given seed does not yield a prime q, a new random
seed is chosen and placed at B<seed>.
DSA_generate_parameters() places the iteration count in
*B<counter_ret> and a counter used for finding a generator in
-*B<h_ret>, unless these are NULL.
+*B<h_ret>, unless these are B<NULL>.
A callback function may be used to provide feedback about the progress
of the key generation. If B<callback> is not B<NULL>, it will be
@@ -37,13 +37,15 @@ called as follows:
=item *
-When the the m-th candidate for q is generated, B<callback(0, m,
-cb_arg)> is called.
+When a candidate for q is generated, B<callback(0, m++, cb_arg)> is called
+(m is 0 for the first candidate).
=item *
-B<callback(1, j++, cb_arg)> is called in the inner loop of the
-Miller-Rabin primality test.
+While a candidate for q is tested, B<callback(1, i, cb_arg)>
+is called in the outer loop of the Miller-Rabin primality tests
+(once for each witness that confirms that the candidate may be prime).
+i is the loop counter (starting at 0).
=item *
@@ -52,10 +54,15 @@ B<callback(3, 0, cb_arg)> are called.
=item *
-While candidates for p are being tested, B<callback(1, j++, cb_arg)>
-is called in the inner loop of the Miller-Rabin primality test, then
-B<callback(0, counter, cb_arg)> is called when the next candidate
-is chosen.
+Before a candidate for p (other than the first) is generated and tested,
+B<callback(0, counter, cb_arg)> is called.
+
+=item *
+
+While a candidate for p is tested, B<callback(1, j++, cb_arg)>
+is called in the outer loop of the Miller-Rabin primality test
+(once for each witness that confirms that the candidate may be prime).
+i is the loop counter (starting at 0).
=item *
@@ -70,15 +77,11 @@ When the generator has been found, B<callback(3, 1, cb_arg)> is called.
=head1 RETURN VALUE
DSA_generate_parameters() returns a pointer to the DSA structure, or
-NULL if the parameter generation fails. The error codes can be
+B<NULL> if the parameter generation fails. The error codes can be
obtained by L<ERR_get_error(3)|ERR_get_error(3)>.
=head1 BUGS
-The deterministic generation of p does not follow the NIST algorithm:
-r0 is SHA1(s+k+1), but should be SHA1(s+j+k) with j_0=2,
-j_counter=j_counter-1 + n + 1.
-
Seed lengths E<gt> 20 are not supported.
=head1 SEE ALSO
@@ -90,5 +93,9 @@ L<DSA_free(3)|DSA_free(3)>
DSA_generate_parameters() appeared in SSLeay 0.8. The B<cb_arg>
argument was added in SSLeay 0.9.0.
-
+In versions up to OpenSSL 0.9.4, B<callback(1, ...)> was called
+in the inner loop of the Miller-Rabin test whenever it reached the
+squaring step (the parameters to B<callback> did not reveal how many
+witnesses had been tested); since OpenSSL 0.9.5, B<callback(1, ...)>
+is called as in BN_is_prime(3), i.e. once for each witness.
=cut