manual: gcrypt updates.

This incudes libgcrypt in the remark on crypto security and
adds an external link to the libgcrypt web page.

diff --git a/web/manual.m4 b/web/manual.m4
index 2af59f5376b4ecfadc6ce12a38b5781698b276ce..3193a2f0ca6ef3901c8cb4c08e897d3e50c65dd3 100644 (file)
--- a/web/manual.m4
+++ b/web/manual.m4
@@ -214,11 +214,13 @@ In any case you'll need
        scripts which run during compilation require the EMPH(Bourne
        again shell).  It is most likely already installed.
 
-       - XREFERENCE(http://www.openssl.org/, openssl). The EMPH(Secure
-       Sockets Layer) library is needed for cryptographic routines
-       on both the server and the client side. It is usually shipped
-       with the distro, but you might have to install the "development
-       package" (called libssl-dev on debian systems) as well.
+       - XREFERENCE(http://www.openssl.org/, openssl) or
+       XREFERENCE(ftp://ftp.gnupg.org/gcrypt/libgcrypt/, libgcrypt).
+       At least one of these two libraries is needed as the backend
+       for cryptographic routines on both the server and the client
+       side. Both openssl and libgcrypt are usually shipped with the
+       distro, but you might have to install the development package
+       (libssl-dev or libgcrypt-dev on debian systems) as well.
 
        - XREFERENCE(ftp://ftp.gnu.org/pub/gnu/help2man, help2man)
        is used to create the man pages.
@@ -526,10 +528,10 @@ as follows:
        this point on the communication is encrypted using the RC4
        stream cipher with the session key known to both peers.
 
-paraslash relies on the quality of openssl's cryptographically strong
-pseudo-random bytes, on the security of the implementation of the
-openssl RSA and RC4 crypto routines and on the infeasibility to invert
-the SHA1 function.
+paraslash relies on the quality of the pseudo-random bytes provided
+by the crypto library (openssl or libgcrypt), on the security of
+the implementation of the RSA and RC4 crypto routines and on the
+infeasibility to invert the SHA1 function.
 
 Neither para_server or para_client create RSA keys on their own. This
 has to be done once for each user as sketched in REFERENCE(Quick start,