1 FreeBSD maintainer's guide to OpenSSH-portable
2 ==============================================
4 00) Make sure your mail spool has plenty of free space. It'll fill up
5 pretty fast once you're done with this checklist.
7 01) Download the latest OpenSSH-portable tarball and signature from
8 OpenBSD (https://ftp.openbsd.org/pub/OpenBSD/OpenSSH/portable/).
10 02) Verify the signature:
12 $ gpg --verify openssh-X.YpZ.tar.gz.asc
14 03) Unpack the tarball in a suitable directory:
16 $ tar xf openssh-X.YpZ.tar.gz
18 04) Copy to the vendor directory:
20 $ svn co svn+ssh://repo.freebsd.org/base/vendor-crypto/openssh/dist
21 $ rsync --archive --delete openssh-X.YpZ/ dist/
23 05) Take care of added / deleted files:
25 $ svn rm $(svn stat dist | awk '$1 == "!" { print $2 }')
26 $ svn add --no-auto-props $(svn stat dist | awk '$1 == "?" { print $2 }')
30 $ svn commit -m "Vendor import of OpenSSH X.YpZ." dist
34 $ svn copy -m "Tag OpenSSH X.YpZ." \
35 svn+ssh://repo.freebsd.org/base/vendor-crypto/openssh/dist \
36 svn+ssh://repo.freebsd.org/base/vendor-crypto/openssh/X.YpZ
38 08) Check out head and run the pre-merge script, which strips our RCS
39 tags from files that have them:
41 $ svn co svn+ssh://repo.freebsd.org/base/head
42 $ cd head/crypto/openssh
43 $ sh freebsd-pre-merge.sh
45 09) Merge from the vendor branch:
47 $ svn merge -cNNNNNN \^/vendor-crypto/openssh/dist .
49 A number of files have been deleted from FreeBSD's copy of ssh,
50 including rendered man pages (which have a .0 extension). When
51 svn prompts for these deleted files during the merge, choose 'r'
52 (leaving them deleted).
54 0A) Resolve conflicts. Remember to bump the version addendum in
55 version.h, and update the default value in ssh{,d}_config and
58 0B) Diff against the vendor branch:
60 $ svn diff --no-diff-deleted --no-diff-added \
61 --ignore-properties \^/vendor-crypto/openssh/X.YpZ .
63 Files that have modifications relative to the vendor code, and
64 only those files, must have the svn:keywords property set to
65 FreeBSD=%H and be listed in the 'keywords' file created by the
68 0C) Run the post-merge script, which re-adds RCS tags to files that
71 $ sh freebsd-post-merge.sh
73 0D) Run the configure script:
75 $ sh freebsd-configure.sh
77 0E) Review changes to config.h very carefully.
79 Note that libwrap should not be defined in config.h; as of
80 r311585 it is conditional on MK_TCP_WRAPPERS.
82 0F) If source files have been added or removed, update the appropriate
83 makefiles to reflect changes in the vendor's Makefile.in.
85 10) Update ssh_namespace.h:
87 $ sh freebsd-namespace.sh
89 11) Build and install world, reboot, test. Pay particular attention
90 to pam_ssh(8), which gropes inside libssh and will break if
91 something significant changes or if ssh_namespace.h is out of
94 12) Commit, and hunker down for the inevitable storm of complaints.
98 An overview of FreeBSD changes to OpenSSH-portable
99 ==================================================
103 The SSH protocol allows for a human-readable version string of up
104 to 40 characters to be appended to the protocol version string.
105 FreeBSD takes advantage of this to include a date indicating the
106 "patch level", so people can easily determine whether their system
107 is vulnerable when an OpenSSH advisory goes out. Some people,
108 however, dislike advertising their patch level in the protocol
109 handshake, so we've added a VersionAddendum configuration variable
110 to allow them to change or disable it. Upstream added support for
111 VersionAddendum on the server side, but we also support it on the
114 1) Modified server-side defaults
116 We've modified some configuration defaults in sshd:
118 - UsePAM defaults to "yes".
119 - PermitRootLogin defaults to "no".
120 - X11Forwarding defaults to "yes".
121 - PasswordAuthentication defaults to "no".
122 - VersionAddendum defaults to "FreeBSD-YYYYMMDD".
123 - PrivilegeSeparation defaults to "sandbox".
124 - UseDNS defaults to "yes".
126 2) Modified client-side defaults
128 We've modified some configuration defaults in ssh:
130 - CheckHostIP defaults to "no".
131 - VerifyHostKeyDNS defaults to "yes" if built with LDNS.
132 - VersionAddendum defaults to "FreeBSD-YYYYMMDD".
134 3) Canonic host names
136 We've added code to ssh.c to canonicize the target host name after
137 reading options but before trying to connect. This eliminates the
138 usual problem with duplicate known_hosts entries.
140 4) setusercontext() environment
142 Our setusercontext(3) can set environment variables, which we must
143 take care to transfer to the child's environment.
147 Support for TCP wrappers was removed in upstream 6.7p1. We've
148 added it back by porting the 6.6p1 code forward.
150 TCP wrappers support in sshd will be disabled in HEAD and will
151 be removed from FreeBSD in the future.
153 6) Agent client reference counting
155 We've added code to ssh-agent.c to implement client reference
156 counting; the agent will automatically exit when the last client
159 7) Class-based login restrictions
161 We've added code to auth2.c to enforce the host.allow, host.deny,
162 times.allow and times.deny login class capabilities.
166 We no longer have the HPN patches (adaptive buffer size for
167 increased throughput on high-BxD links), but we recognize and
168 ignore HPN-related configuration options to avoid breaking existing
173 This port was brought to you by (in no particular order) DARPA, NAI
174 Labs, ThinkSec, Nescafé, the Aberlour Glenlivet Distillery Co.,
175 Suzanne Vega, and a Sanford's #69 Deluxe Marker.