From owner-svn-src-head@freebsd.org Wed Mar 18 00:05:59 2020 Return-Path: Delivered-To: svn-src-head@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id 440A82766AF; Wed, 18 Mar 2020 00:05:59 +0000 (UTC) (envelope-from jhb@FreeBSD.org) Received: from smtp.freebsd.org (smtp.freebsd.org [96.47.72.83]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) server-signature RSA-PSS (4096 bits) client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "smtp.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 48hr0k3R67z4bDC; Wed, 18 Mar 2020 00:05:58 +0000 (UTC) (envelope-from jhb@FreeBSD.org) Received: from John-Baldwins-MacBook-Pro-8.local (unknown [IPv6:2601:648:8881:1e90:b814:3297:d0a:b7c3]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client did not present a certificate) (Authenticated sender: jhb) by smtp.freebsd.org (Postfix) with ESMTPSA id 7E0C05593; Wed, 18 Mar 2020 00:05:57 +0000 (UTC) (envelope-from jhb@FreeBSD.org) Subject: Re: svn commit: r359053 - head/sys/kern To: Ian Lepore , Conrad Meyer , src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org References: <202003172227.02HMRHLM086023@repo.freebsd.org> <047c4edb4ff9fa6c40be6492c2f082e374f7a941.camel@freebsd.org> From: John Baldwin Autocrypt: addr=jhb@FreeBSD.org; keydata= mQGiBETQ+XcRBADMFybiq69u+fJRy/0wzqTNS8jFfWaBTs5/OfcV7wWezVmf9sgwn8TW0Dk0 c9MBl0pz+H01dA2ZSGZ5fXlmFIsee1WEzqeJzpiwd/pejPgSzXB9ijbLHZ2/E0jhGBcVy5Yo /Tw5+U/+laeYKu2xb0XPvM0zMNls1ah5OnP9a6Ql6wCgupaoMySb7DXm2LHD1Z9jTsHcAQMD /1jzh2BoHriy/Q2s4KzzjVp/mQO5DSm2z14BvbQRcXU48oAosHA1u3Wrov6LfPY+0U1tG47X 1BGfnQH+rNAaH0livoSBQ0IPI/8WfIW7ub4qV6HYwWKVqkDkqwcpmGNDbz3gfaDht6nsie5Z pcuCcul4M9CW7Md6zzyvktjnbz61BADGDCopfZC4of0Z3Ka0u8Wik6UJOuqShBt1WcFS8ya1 oB4rc4tXfSHyMF63aPUBMxHR5DXeH+EO2edoSwViDMqWk1jTnYza51rbGY+pebLQOVOxAY7k do5Ordl3wklBPMVEPWoZ61SdbcjhHVwaC5zfiskcxj5wwXd2E9qYlBqRg7QeSm9obiBCYWxk d2luIDxqaGJARnJlZUJTRC5vcmc+iGAEExECACAFAkTQ+awCGwMGCwkIBwMCBBUCCAMEFgID AQIeAQIXgAAKCRBy3lIGd+N/BI6RAJ9S97fvbME+3hxzE3JUyUZ6vTewDACdE1stFuSfqMvM jomvZdYxIYyTUpC5Ag0ERND5ghAIAPwsO0B7BL+bz8sLlLoQktGxXwXQfS5cInvL17Dsgnr3 1AKa94j9EnXQyPEj7u0d+LmEe6CGEGDh1OcGFTMVrof2ZzkSy4+FkZwMKJpTiqeaShMh+Goj XlwIMDxyADYvBIg3eN5YdFKaPQpfgSqhT+7El7w+wSZZD8pPQuLAnie5iz9C8iKy4/cMSOrH YUK/tO+Nhw8Jjlw94Ik0T80iEhI2t+XBVjwdfjbq3HrJ0ehqdBwukyeJRYKmbn298KOFQVHO EVbHA4rF/37jzaMadK43FgJ0SAhPPF5l4l89z5oPu0b/+5e2inA3b8J3iGZxywjM+Csq1tqz hltEc7Q+E08AAwUIAL+15XH8bPbjNJdVyg2CMl10JNW2wWg2Q6qdljeaRqeR6zFus7EZTwtX sNzs5bP8y51PSUDJbeiy2RNCNKWFMndM22TZnk3GNG45nQd4OwYK0RZVrikalmJY5Q6m7Z16 4yrZgIXFdKj2t8F+x613/SJW1lIr9/bDp4U9tw0V1g3l2dFtD3p3ZrQ3hpoDtoK70ioIAjjH aIXIAcm3FGZFXy503DOA0KaTWwvOVdYCFLm3zWuSOmrX/GsEc7ovasOWwjPn878qVjbUKWwx Q4QkF4OhUV9zPtf9tDSAZ3x7QSwoKbCoRCZ/xbyTUPyQ1VvNy/mYrBcYlzHodsaqUDjHuW+I SQQYEQIACQUCRND5ggIbDAAKCRBy3lIGd+N/BCO8AJ9j1dWVQWxw/YdTbEyrRKOY8YZNwwCf afMAg8QvmOWnHx3wl8WslCaXaE8= Message-ID: Date: Tue, 17 Mar 2020 17:05:55 -0700 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.12; rv:68.0) Gecko/20100101 Thunderbird/68.5.0 MIME-Version: 1.0 In-Reply-To: <047c4edb4ff9fa6c40be6492c2f082e374f7a941.camel@freebsd.org> Content-Type: text/plain; charset=windows-1252 Content-Language: en-US Content-Transfer-Encoding: 7bit X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: SVN commit messages for the src tree for head/-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 18 Mar 2020 00:05:59 -0000 On 3/17/20 3:36 PM, Ian Lepore wrote: > On Tue, 2020-03-17 at 22:27 +0000, Conrad Meyer wrote: >> Author: cem >> Date: Tue Mar 17 22:27:16 2020 >> New Revision: 359053 >> URL: https://svnweb.freebsd.org/changeset/base/359053 >> >> Log: >> Implement sysctl kern.boot_id >> >> Boot IDs are random, opaque 128-bit identifiers that distinguish distinct >> system boots. A new ID is generated each time the system boots. Unlike >> kern.boottime, the value is not modified by NTP adjustments. It remains fixed >> until the machine is restarted. >> >> PR: 244867 >> Reported by: Ricardo Fraile >> MFC after: I do not intend to, but feel free >> >> Modified: >> head/sys/kern/kern_mib.c >> >> Modified: head/sys/kern/kern_mib.c >> ============================================================================== >> --- head/sys/kern/kern_mib.c Tue Mar 17 21:29:03 2020 (r359052) >> +++ head/sys/kern/kern_mib.c Tue Mar 17 22:27:16 2020 (r359053) >> @@ -448,6 +448,32 @@ SYSCTL_PROC(_kern, KERN_HOSTID, hostid, >> CTLTYPE_ULONG | CTLFLAG_RW | CTLFLAG_PRISON | CTLFLAG_MPSAFE | CTLFLAG_CAPRD, >> NULL, 0, sysctl_hostid, "LU", "Host ID"); >> >> +static struct mtx bootid_lk; >> +MTX_SYSINIT(bootid_lock, &bootid_lk, "bootid generator lock", MTX_DEF); >> + >> +static int >> +sysctl_bootid(SYSCTL_HANDLER_ARGS) >> +{ >> + static uint8_t boot_id[16]; >> + static bool initialized = false; >> + >> + mtx_lock(&bootid_lk); >> + if (!initialized) { >> + if (!is_random_seeded()) { >> + mtx_unlock(&bootid_lk); >> + return (ENXIO); >> + } >> + arc4random_buf(boot_id, sizeof(boot_id)); >> + initialized = true; >> + } >> + mtx_unlock(&bootid_lk); >> + >> + return (SYSCTL_OUT(req, boot_id, sizeof(boot_id))); >> +} >> +SYSCTL_PROC(_kern, OID_AUTO, boot_id, >> + CTLTYPE_STRUCT | CTLFLAG_RD | CTLFLAG_MPSAFE | CTLFLAG_CAPRD, >> + NULL, 0, sysctl_bootid, "", "Random boot ID"); >> + >> /* >> * The osrelease string is copied from the global (osrelease in vers.c) into >> * prison0 by a sysinit and is inherited by child jails if not changed at jail > > This seems a bit complex. Why run a sysinit to init a mutex so that > you can safely do a lazy init of boot_id? Seems like it would be much > easier to just use a sysinit at SI_SUB_LAST to init boot_id before > sysctl can reference it. Presumably you may not have enough entropy by SI_SUB_LAST to generate it? -- John Baldwin