1 FreeBSD maintainer's guide to OpenSSH-portable 2 ============================================== 3 4 These instructions assume you have a clone of the FreeBSD git repo 5 main branch in src/freebsd/main, and will store vendor trees under 6 src/freebsd/vendor/. In addition, this assumes there is a "freebsd" 7 origin pointing to git(repo).freebsd.org/src.git. 8 901) Make sure your mail spool has plenty of free space. It'll fill up 10 pretty fast once you're done with this checklist. 11 1202) Download the latest OpenSSH-portable tarball and signature from 13 OpenBSD (https://ftp.openbsd.org/pub/OpenBSD/OpenSSH/portable/). 14 1503) Verify the signature: 16 17 $ gpg --verify openssh-X.YpZ.tar.gz.asc 18 1904) Unpack the tarball in a suitable directory: 20 21 $ tar xf openssh-X.YpZ.tar.gz 22 2305) Copy to a vendor branch: 24 25 $ cd src/freebsd/main 26 $ git worktree add ../vendor/openssh freebsd/vendor/openssh 27 $ cd ../vendor/openssh 28 $ rsync --archive --delete --exclude=.git /path/to/openssh-X.YpZ/ ./ 29 3006) Take care of added / deleted files: 31 32 $ git add -A 33 3407) Commit: 35 36 $ git commit -m "Vendor import of OpenSSH X.YpZ" 37 3808) Tag: 39 40 $ git tag -a -m "Tag OpenSSH X.YpZ" vendor/openssh/X.YpZ 41 42 At this point the vendor branch can be pushed to the FreeBSD repo via: 43 44 $ git push freebsd vendor/openssh 45 $ git push freebsd vendor/openssh/X.YpZ 46 47 Note the second "git push" command is used to push the tag, which is 48 not pushed by default. 49 50 It is also possible to push the branch and tag together, but use 51 --dry-run first to ensure that no undesired tags will be pushed: 52 53 $ git push --dry-run --follow-tags freebsd vendor/openssh 54 $ git push --follow-tags freebsd vendor/openssh 55 56 The update and tag could instead be pushed later, along with the merge 57 to main, but pushing now allows others to collaborate. 58 5909) Merge from the vendor branch: 60 61 $ git subtree merge -P crypto/openssh vendor/openssh 62 63 A number of files have been deleted from FreeBSD's copy of ssh, 64 including rendered man pages (which have a .0 extension). When 65 git prompts for these deleted files during the merge, choose 'd' 66 (leaving them deleted). 67 6810) Resolve conflicts. Remember to bump the version addendum in 69 version.h, and update the default value in ssh{,d}_config and 70 ssh{,d}_config.5. 71 7211) Diff against the vendor branch: 73 74 $ git diff --diff-filter=M vendor/openssh/X.YpZ HEAD:crypto/openssh 75 76 Files that have modifications relative to the vendor code, and 77 only those files, must have the svn:keywords property set to 78 FreeBSD=%H and be listed in the 'keywords' file created by the 79 pre-merge script. 80 8112) Run the configure script: 82 83 $ sh freebsd-configure.sh 84 8513) Review changes to config.h very carefully. 86 87 Note that libwrap should not be defined in config.h; as of 88 r311585 (233932cc2a60) it is conditional on MK_TCP_WRAPPERS. 89 9014) If source files have been added or removed, update the appropriate 91 makefiles to reflect changes in the vendor's Makefile.in. 92 9315) Update ssh_namespace.h: 94 95 $ sh freebsd-namespace.sh 96 9716) Build and install world, reboot, test. Pay particular attention 98 to pam_ssh(8), which gropes inside libssh and will break if 99 something significant changes or if ssh_namespace.h is out of 100 whack. 101 10217) Check for references to obsolete configuration options 103 (e.g., ChallengeResponseAuthentication in sshd_config) which 104 may exist in release/ scripts. 105 10618) Commit, and hunker down for the inevitable storm of complaints. 107 108 109 110 An overview of FreeBSD changes to OpenSSH-portable 111 ================================================== 112 1131) Modified server-side defaults 114 115 We've modified some configuration defaults in sshd: 116 117 - UsePAM defaults to "yes". 118 - PermitRootLogin defaults to "no". 119 - X11Forwarding defaults to "yes". 120 - PasswordAuthentication defaults to "no". 121 - VersionAddendum defaults to "FreeBSD-YYYYMMDD". 122 - UseDNS defaults to "yes". 123 1242) Modified client-side defaults 125 126 We've modified some configuration defaults in ssh: 127 128 - CheckHostIP defaults to "no". 129 - VerifyHostKeyDNS defaults to "yes" if built with LDNS. 130 1313) Canonic host names 132 133 We've added code to ssh.c to canonicize the target host name after 134 reading options but before trying to connect. This eliminates the 135 usual problem with duplicate known_hosts entries. 136 1374) setusercontext() environment 138 139 Our setusercontext(3) can set environment variables, which we must 140 take care to transfer to the child's environment. 141 1425) TCP wrappers 143 144 Support for TCP wrappers was removed in upstream 6.7p1. We've 145 added it back by porting the 6.6p1 code forward. 146 147 TCP wrappers support in sshd will be disabled in HEAD and will 148 be removed from FreeBSD in the future. 149 1506) Agent client reference counting 151 152 We've added code to ssh-agent.c to implement client reference 153 counting; the agent will automatically exit when the last client 154 disconnects. 155 1567) Class-based login restrictions (27ceebbc2402) 157 158 We've added code to auth.c to enforce the host.allow, host.deny, 159 times.allow and times.deny login class capabilities, based on an 160 upstream submission from 161 https://github.com/openssh/openssh-portable/pull/262. 162 1638) Blocklist integration 164 165 We include blocklist (https://github.com/zoulasc/blocklist) in FreeBSD, 166 and ssh is patched to report login failures to it. 167 1689) Paths 169 170 A number of paths are changed to match FreeBSD's configuration (e.g., 171 using /usr/local/ instead of /uxr/X11R6/). 172 17310) Retired patches 174 175 We no longer have HPN patches (adaptive buffer size for increased 176 throughput on high-BxD links) or client-side VersionAddendum, but we 177 recognize and ignore the configuration options to avoid breaking 178 existing configurations. 179 180 181 182This port was brought to you by (in no particular order) DARPA, NAI 183Labs, ThinkSec, Nescafé, the Aberlour Glenlivet Distillery Co., 184Suzanne Vega, and a Sanford's #69 Deluxe Marker. 185 186 -- des@FreeBSD.org 187