Date: Fri, 22 Nov 2019 13:07:11 -0800 From: Conrad Meyer <cem@freebsd.org> To: Ravi Pokala <rpokala@freebsd.org> Cc: src-committers <src-committers@freebsd.org>, svn-src-all <svn-src-all@freebsd.org>, svn-src-head <svn-src-head@freebsd.org> Subject: Re: svn commit: r355018 - in head/sys: dev/random sys Message-ID: <CAG6CVpXkfM25tMjJz3q63wSYC34KkGO0VATm1YUR8ZYG=nBX8w@mail.gmail.com> In-Reply-To: <85EFA1CD-5093-4588-9FA4-F704DA122674@panasas.com> References: <201911222020.xAMKKbE0017524@repo.freebsd.org> <85EFA1CD-5093-4588-9FA4-F704DA122674@panasas.com>
next in thread | previous in thread | raw e-mail | index | archive | help
It wasn't lost in the change. The parameters now have the names "entropy" and "len," but it is the same functionality. Best, Conrad On Fri, Nov 22, 2019 at 12:56 PM Ravi Pokala <rpokala@freebsd.org> wrote: > > Hi Conrad, > > The original code did > > explicit_bzero(data, size); > > which appears to have been lost in this change. Is that intentional? If s= o, why is that okay? > > Thanks, > > Ravi (rpokala@) > > =EF=BB=BF-----Original Message----- > From: <owner-src-committers@freebsd.org> on behalf of Conrad Meyer <cem@F= reeBSD.org> > Date: 2019-11-22, Friday at 12:20 > To: <src-committers@freebsd.org>, <svn-src-all@freebsd.org>, <svn-src-hea= d@freebsd.org> > Subject: svn commit: r355018 - in head/sys: dev/random sys > > Author: cem > Date: Fri Nov 22 20:20:37 2019 > New Revision: 355018 > URL: https://svnweb.freebsd.org/changeset/base/355018 > > Log: > random(4): Abstract loader entropy injection > > Break random_harvestq_prime up into some logical subroutines. The = goal > is that it becomes easier to add other early entropy sources. > > While here, drop pre-12.0 compatibility logic. loader default conf= iguration > should preload the file as expeced since 12.0. > > Approved by: csprng(delphij, markm) > Differential Revision: https://reviews.freebsd.org/D22482 > > Modified: > head/sys/dev/random/random_harvestq.c > head/sys/sys/random.h > > Modified: head/sys/dev/random/random_harvestq.c > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D > --- head/sys/dev/random/random_harvestq.c Fri Nov 22 20:18:07 2019 = (r355017) > +++ head/sys/dev/random/random_harvestq.c Fri Nov 22 20:20:37 2019 = (r355018) > @@ -402,6 +402,57 @@ random_harvestq_init(void *unused __unused) > SYSINIT(random_device_h_init, SI_SUB_RANDOM, SI_ORDER_SECOND, random= _harvestq_init, NULL); > > /* > + * Subroutine to slice up a contiguous chunk of 'entropy' and feed i= t into the > + * underlying algorithm. Returns number of bytes actually fed into = underlying > + * algorithm. > + */ > +static size_t > +random_early_prime(char *entropy, size_t len) > +{ > + struct harvest_event event; > + size_t i; > + > + len =3D rounddown(len, sizeof(event.he_entropy)); > + if (len =3D=3D 0) > + return (0); > + > + for (i =3D 0; i < len; i +=3D sizeof(event.he_entropy)) { > + event.he_somecounter =3D (uint32_t)get_cyclecount(); > + event.he_size =3D sizeof(event.he_entropy); > + event.he_source =3D RANDOM_CACHED; > + event.he_destination =3D > + harvest_context.hc_destination[RANDOM_CACHED]++; > + memcpy(event.he_entropy, entropy + i, sizeof(event.he_ent= ropy)); > + random_harvestq_fast_process_event(&event); > + } > + explicit_bzero(entropy, len); > + return (len); > +} > + > +/* > + * Subroutine to search for known loader-loaded files in memory and = feed them > + * into the underlying algorithm early in boot. Returns the number = of bytes > + * loaded (zero if none were loaded). > + */ > +static size_t > +random_prime_loader_file(const char *type) > +{ > + uint8_t *keyfile, *data; > + size_t size; > + > + keyfile =3D preload_search_by_type(type); > + if (keyfile =3D=3D NULL) > + return (0); > + > + data =3D preload_fetch_addr(keyfile); > + size =3D preload_fetch_size(keyfile); > + if (data =3D=3D NULL) > + return (0); > + > + return (random_early_prime(data, size)); > +} > + > +/* > * This is used to prime the RNG by grabbing any early random stuff > * known to the kernel, and inserting it directly into the hashing > * module, currently Fortuna. > @@ -410,41 +461,19 @@ SYSINIT(random_device_h_init, SI_SUB_RANDOM, SI= _ORDER_ > static void > random_harvestq_prime(void *unused __unused) > { > - struct harvest_event event; > - size_t count, size, i; > - uint8_t *keyfile, *data; > + size_t size; > > /* > * Get entropy that may have been preloaded by loader(8) > * and use it to pre-charge the entropy harvest queue. > */ > - keyfile =3D preload_search_by_type(RANDOM_CACHED_BOOT_ENTROPY_MOD= ULE); > -#ifndef NO_BACKWARD_COMPATIBILITY > - if (keyfile =3D=3D NULL) > - keyfile =3D preload_search_by_type(RANDOM_LEGACY_BOOT_ENTROPY= _MODULE); > -#endif > - if (keyfile !=3D NULL) { > - data =3D preload_fetch_addr(keyfile); > - size =3D preload_fetch_size(keyfile); > - /* Trim the size. If the admin has a file with a funny si= ze, we lose some. Tough. */ > - size -=3D (size % sizeof(event.he_entropy)); > - if (data !=3D NULL && size !=3D 0) { > - for (i =3D 0; i < size; i +=3D sizeof(event.he_en= tropy)) { > - count =3D sizeof(event.he_entropy); > - event.he_somecounter =3D (uint32_t)get_cy= clecount(); > - event.he_size =3D count; > - event.he_source =3D RANDOM_CACHED; > - event.he_destination =3D > - harvest_context.hc_destination[RANDOM= _CACHED]++; > - memcpy(event.he_entropy, data + i, sizeof= (event.he_entropy)); > - random_harvestq_fast_process_event(&event= ); > - } > - explicit_bzero(data, size); > - if (bootverbose) > - printf("random: read %zu bytes from prelo= aded cache\n", size); > - } else > - if (bootverbose) > - printf("random: no preloaded entropy cach= e\n"); > + size =3D random_prime_loader_file(RANDOM_CACHED_BOOT_ENTROPY_MODU= LE); > + if (bootverbose) { > + if (size > 0) > + printf("random: read %zu bytes from preloaded cac= he\n", > + size); > + else > + printf("random: no preloaded entropy cache\n"); > } > } > SYSINIT(random_device_prime, SI_SUB_RANDOM, SI_ORDER_MIDDLE, random_= harvestq_prime, NULL); > > Modified: head/sys/sys/random.h > =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D > --- head/sys/sys/random.h Fri Nov 22 20:18:07 2019 (r355017) > +++ head/sys/sys/random.h Fri Nov 22 20:20:37 2019 (r355018) > @@ -81,7 +81,6 @@ enum random_entropy_source { > _Static_assert(ENTROPYSOURCE <=3D 32, > "hardcoded assumption that values fit in a typical word-sized bi= tset"); > > -#define RANDOM_LEGACY_BOOT_ENTROPY_MODULE "/boot/entropy" > #define RANDOM_CACHED_BOOT_ENTROPY_MODULE "boot_entropy_cache" > > extern u_int hc_source_mask; > > >
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?CAG6CVpXkfM25tMjJz3q63wSYC34KkGO0VATm1YUR8ZYG=nBX8w>