openssl/crypto/rand/rand_vms.c

612 lines
17 KiB
C
Raw Normal View History

/*
* Copyright 2001-2019 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the OpenSSL license (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
* in the file LICENSE in the source distribution or at
* https://www.openssl.org/source/license.html
*/
#include "e_os.h"
#if defined(OPENSSL_SYS_VMS)
# define __NEW_STARLET 1 /* New starlet definitions since VMS 7.0 */
DRBG: implement a get_nonce() callback Fixes #5849 In pull request #5503 a fallback was added which adds a random nonce of security_strength/2 bits if no nonce callback is provided. This change raised the entropy requirements form 256 to 384 bit, which can cause problems on some platforms (e.g. VMS, see issue #5849). The requirements for the nonce are given in section 8.6.7 of NIST SP 800-90Ar1: A nonce may be required in the construction of a seed during instantiation in order to provide a security cushion to block certain attacks. The nonce shall be either: a) A value with at least (security_strength/2) bits of entropy, or b) A value that is expected to repeat no more often than a (security_strength/2)-bit random string would be expected to repeat. Each nonce shall be unique to the cryptographic module in which instantiation is performed, but need not be secret. When used, the nonce shall be considered to be a critical security parameter. This commit implements a nonce of type b) in order to lower the entropy requirements during instantiation back to 256 bits. The formulation "shall be unique to the cryptographic module" above implies that the nonce needs to be unique among (with high probability) among all DRBG instances in "space" and "time". We try to achieve this goal by creating a nonce of the following form nonce = app-specific-data || high-resolution-utc-timestamp || counter Where || denotes concatenation. The application specific data can be something like the process or group id of the application. A utc timestamp is used because it increases monotonically, provided the system time is synchronized. This approach may not be perfect yet for a FIPS evaluation, but it should be good enough for the moment. This commit also harmonizes the implementation of the get_nonce() and the get_additional_data() callbacks and moves the platform specific parts from rand_lib.c into rand_unix.c, rand_win.c, and rand_vms.c. Reviewed-by: Richard Levitte <levitte@openssl.org> (Merged from https://github.com/openssl/openssl/pull/5920)
2018-04-10 08:22:52 +00:00
# include <unistd.h>
# include "internal/cryptlib.h"
# include <openssl/rand.h>
# include "crypto/rand.h"
# include "rand_local.h"
# include <descrip.h>
# include <dvidef.h>
# include <jpidef.h>
# include <rmidef.h>
# include <syidef.h>
# include <ssdef.h>
# include <starlet.h>
# include <efndef.h>
# include <gen64def.h>
# include <iosbdef.h>
# include <iledef.h>
# include <lib$routines.h>
# ifdef __DECC
# pragma message disable DOLLARID
# endif
# include <dlfcn.h> /* SYS$GET_ENTROPY presence */
# ifndef OPENSSL_RAND_SEED_OS
# error "Unsupported seeding method configured; must be os"
# endif
/*
* DATA COLLECTION METHOD
* ======================
*
* This is a method to get low quality entropy.
* It works by collecting all kinds of statistical data that
* VMS offers and using them as random seed.
*/
/* We need to make sure we have the right size pointer in some cases */
# if __INITIAL_POINTER_SIZE == 64
# pragma pointer_size save
# pragma pointer_size 32
# endif
typedef uint32_t *uint32_t__ptr32;
# if __INITIAL_POINTER_SIZE == 64
# pragma pointer_size restore
# endif
struct item_st {
short length, code; /* length is number of bytes */
};
static const struct item_st DVI_item_data[] = {
{4, DVI$_ERRCNT},
{4, DVI$_REFCNT},
};
static const struct item_st JPI_item_data[] = {
{4, JPI$_BUFIO},
{4, JPI$_CPUTIM},
{4, JPI$_DIRIO},
{4, JPI$_IMAGECOUNT},
{4, JPI$_PAGEFLTS},
{4, JPI$_PID},
{4, JPI$_PPGCNT},
{4, JPI$_WSPEAK},
/*
* Note: the direct result is just a 32-bit address. However, it points
* to a list of 4 32-bit words, so we make extra space for them so we can
* do in-place replacement of values
*/
{16, JPI$_FINALEXC},
};
static const struct item_st JPI_item_data_64bit[] = {
{8, JPI$_LAST_LOGIN_I},
{8, JPI$_LOGINTIM},
};
static const struct item_st RMI_item_data[] = {
{4, RMI$_COLPG},
{4, RMI$_MWAIT},
{4, RMI$_CEF},
{4, RMI$_PFW},
{4, RMI$_LEF},
{4, RMI$_LEFO},
{4, RMI$_HIB},
{4, RMI$_HIBO},
{4, RMI$_SUSP},
{4, RMI$_SUSPO},
{4, RMI$_FPG},
{4, RMI$_COM},
{4, RMI$_COMO},
{4, RMI$_CUR},
#if defined __alpha
{4, RMI$_FRLIST},
{4, RMI$_MODLIST},
#endif
{4, RMI$_FAULTS},
{4, RMI$_PREADS},
{4, RMI$_PWRITES},
{4, RMI$_PWRITIO},
{4, RMI$_PREADIO},
{4, RMI$_GVALFLTS},
{4, RMI$_WRTINPROG},
{4, RMI$_FREFLTS},
{4, RMI$_DZROFLTS},
{4, RMI$_SYSFAULTS},
{4, RMI$_ISWPCNT},
{4, RMI$_DIRIO},
{4, RMI$_BUFIO},
{4, RMI$_MBREADS},
{4, RMI$_MBWRITES},
{4, RMI$_LOGNAM},
{4, RMI$_FCPCALLS},
{4, RMI$_FCPREAD},
{4, RMI$_FCPWRITE},
{4, RMI$_FCPCACHE},
{4, RMI$_FCPCPU},
{4, RMI$_FCPHIT},
{4, RMI$_FCPSPLIT},
{4, RMI$_FCPFAULT},
{4, RMI$_ENQNEW},
{4, RMI$_ENQCVT},
{4, RMI$_DEQ},
{4, RMI$_BLKAST},
{4, RMI$_ENQWAIT},
{4, RMI$_ENQNOTQD},
{4, RMI$_DLCKSRCH},
{4, RMI$_DLCKFND},
{4, RMI$_NUMLOCKS},
{4, RMI$_NUMRES},
{4, RMI$_ARRLOCPK},
{4, RMI$_DEPLOCPK},
{4, RMI$_ARRTRAPK},
{4, RMI$_TRCNGLOS},
{4, RMI$_RCVBUFFL},
{4, RMI$_ENQNEWLOC},
{4, RMI$_ENQNEWIN},
{4, RMI$_ENQNEWOUT},
{4, RMI$_ENQCVTLOC},
{4, RMI$_ENQCVTIN},
{4, RMI$_ENQCVTOUT},
{4, RMI$_DEQLOC},
{4, RMI$_DEQIN},
{4, RMI$_DEQOUT},
{4, RMI$_BLKLOC},
{4, RMI$_BLKIN},
{4, RMI$_BLKOUT},
{4, RMI$_DIRIN},
{4, RMI$_DIROUT},
/* We currently get a fault when trying these. TODO: To be figured out. */
#if 0
{140, RMI$_MSCP_EVERYTHING}, /* 35 32-bit words */
{152, RMI$_DDTM_ALL}, /* 38 32-bit words */
{80, RMI$_TMSCP_EVERYTHING} /* 20 32-bit words */
#endif
{4, RMI$_LPZ_PAGCNT},
{4, RMI$_LPZ_HITS},
{4, RMI$_LPZ_MISSES},
{4, RMI$_LPZ_EXPCNT},
{4, RMI$_LPZ_ALLOCF},
{4, RMI$_LPZ_ALLOC2},
{4, RMI$_ACCESS},
{4, RMI$_ALLOC},
{4, RMI$_FCPCREATE},
{4, RMI$_VOLWAIT},
{4, RMI$_FCPTURN},
{4, RMI$_FCPERASE},
{4, RMI$_OPENS},
{4, RMI$_FIDHIT},
{4, RMI$_FIDMISS},
{4, RMI$_FILHDR_HIT},
{4, RMI$_DIRFCB_HIT},
{4, RMI$_DIRFCB_MISS},
{4, RMI$_DIRDATA_HIT},
{4, RMI$_EXTHIT},
{4, RMI$_EXTMISS},
{4, RMI$_QUOHIT},
{4, RMI$_QUOMISS},
{4, RMI$_STORAGMAP_HIT},
{4, RMI$_VOLLCK},
{4, RMI$_SYNCHLCK},
{4, RMI$_SYNCHWAIT},
{4, RMI$_ACCLCK},
{4, RMI$_XQPCACHEWAIT},
{4, RMI$_DIRDATA_MISS},
{4, RMI$_FILHDR_MISS},
{4, RMI$_STORAGMAP_MISS},
{4, RMI$_PROCCNTMAX},
{4, RMI$_PROCBATCNT},
{4, RMI$_PROCINTCNT},
{4, RMI$_PROCNETCNT},
{4, RMI$_PROCSWITCHCNT},
{4, RMI$_PROCBALSETCNT},
{4, RMI$_PROCLOADCNT},
{4, RMI$_BADFLTS},
{4, RMI$_EXEFAULTS},
{4, RMI$_HDRINSWAPS},
{4, RMI$_HDROUTSWAPS},
{4, RMI$_IOPAGCNT},
{4, RMI$_ISWPCNTPG},
{4, RMI$_OSWPCNT},
{4, RMI$_OSWPCNTPG},
{4, RMI$_RDFAULTS},
{4, RMI$_TRANSFLTS},
{4, RMI$_WRTFAULTS},
#if defined __alpha
{4, RMI$_USERPAGES},
#endif
{4, RMI$_VMSPAGES},
{4, RMI$_TTWRITES},
{4, RMI$_BUFOBJPAG},
{4, RMI$_BUFOBJPAGPEAK},
{4, RMI$_BUFOBJPAGS01},
{4, RMI$_BUFOBJPAGS2},
{4, RMI$_BUFOBJPAGMAXS01},
{4, RMI$_BUFOBJPAGMAXS2},
{4, RMI$_BUFOBJPAGPEAKS01},
{4, RMI$_BUFOBJPAGPEAKS2},
{4, RMI$_BUFOBJPGLTMAXS01},
{4, RMI$_BUFOBJPGLTMAXS2},
{4, RMI$_DLCK_INCMPLT},
{4, RMI$_DLCKMSGS_IN},
{4, RMI$_DLCKMSGS_OUT},
{4, RMI$_MCHKERRS},
{4, RMI$_MEMERRS},
};
static const struct item_st RMI_item_data_64bit[] = {
#if defined __ia64
{8, RMI$_FRLIST},
{8, RMI$_MODLIST},
#endif
{8, RMI$_LCKMGR_REQCNT},
{8, RMI$_LCKMGR_REQTIME},
{8, RMI$_LCKMGR_SPINCNT},
{8, RMI$_LCKMGR_SPINTIME},
{8, RMI$_CPUINTSTK},
{8, RMI$_CPUMPSYNCH},
{8, RMI$_CPUKERNEL},
{8, RMI$_CPUEXEC},
{8, RMI$_CPUSUPER},
{8, RMI$_CPUUSER},
#if defined __ia64
{8, RMI$_USERPAGES},
#endif
{8, RMI$_TQETOTAL},
{8, RMI$_TQESYSUB},
{8, RMI$_TQEUSRTIMR},
{8, RMI$_TQEUSRWAKE},
};
static const struct item_st SYI_item_data[] = {
{4, SYI$_PAGEFILE_FREE},
};
/*
* Input:
* items_data - an array of lengths and codes
* items_data_num - number of elements in that array
*
* Output:
* items - pre-allocated ILE3 array to be filled.
* It's assumed to have items_data_num elements plus
* one extra for the terminating NULL element
* databuffer - pre-allocated 32-bit word array.
*
* Returns the number of elements used in databuffer
*/
static size_t prepare_item_list(const struct item_st *items_input,
size_t items_input_num,
ILE3 *items,
uint32_t__ptr32 databuffer)
{
size_t data_sz = 0;
for (; items_input_num-- > 0; items_input++, items++) {
items->ile3$w_code = items_input->code;
/* Special treatment of JPI$_FINALEXC */
if (items->ile3$w_code == JPI$_FINALEXC)
items->ile3$w_length = 4;
else
items->ile3$w_length = items_input->length;
items->ile3$ps_bufaddr = databuffer;
items->ile3$ps_retlen_addr = 0;
databuffer += items_input->length / sizeof(databuffer[0]);
data_sz += items_input->length;
}
/* Terminating NULL entry */
items->ile3$w_length = items->ile3$w_code = 0;
items->ile3$ps_bufaddr = items->ile3$ps_retlen_addr = NULL;
return data_sz / sizeof(databuffer[0]);
}
static void massage_JPI(ILE3 *items)
{
/*
* Special treatment of JPI$_FINALEXC
* The result of that item's data buffer is a 32-bit address to a list of
* 4 32-bit words.
*/
for (; items->ile3$w_length != 0; items++) {
if (items->ile3$w_code == JPI$_FINALEXC) {
uint32_t *data = items->ile3$ps_bufaddr;
uint32_t *ptr = (uint32_t *)*data;
size_t j;
/*
* We know we made space for 4 32-bit words, so we can do in-place
* replacement.
*/
for (j = 0; j < 4; j++)
data[j] = ptr[j];
break;
}
}
}
/*
* This number expresses how many bits of data contain 1 bit of entropy.
*
* For the moment, we assume about 0.05 entropy bits per data bit, or 1
* bit of entropy per 20 data bits.
*/
#define ENTROPY_FACTOR 20
size_t data_collect_method(RAND_POOL *pool)
{
ILE3 JPI_items_64bit[OSSL_NELEM(JPI_item_data_64bit) + 1];
ILE3 RMI_items_64bit[OSSL_NELEM(RMI_item_data_64bit) + 1];
ILE3 DVI_items[OSSL_NELEM(DVI_item_data) + 1];
ILE3 JPI_items[OSSL_NELEM(JPI_item_data) + 1];
ILE3 RMI_items[OSSL_NELEM(RMI_item_data) + 1];
ILE3 SYI_items[OSSL_NELEM(SYI_item_data) + 1];
union {
/* This ensures buffer starts at 64 bit boundary */
uint64_t dummy;
uint32_t buffer[OSSL_NELEM(JPI_item_data_64bit) * 2
+ OSSL_NELEM(RMI_item_data_64bit) * 2
+ OSSL_NELEM(DVI_item_data)
+ OSSL_NELEM(JPI_item_data)
+ OSSL_NELEM(RMI_item_data)
+ OSSL_NELEM(SYI_item_data)
+ 4 /* For JPI$_FINALEXC */];
} data;
size_t total_elems = 0;
size_t total_length = 0;
size_t bytes_needed = rand_pool_bytes_needed(pool, ENTROPY_FACTOR);
size_t bytes_remaining = rand_pool_bytes_remaining(pool);
/* Take all the 64-bit items first, to ensure proper alignment of data */
total_elems +=
prepare_item_list(JPI_item_data_64bit, OSSL_NELEM(JPI_item_data_64bit),
JPI_items_64bit, &data.buffer[total_elems]);
total_elems +=
prepare_item_list(RMI_item_data_64bit, OSSL_NELEM(RMI_item_data_64bit),
RMI_items_64bit, &data.buffer[total_elems]);
/* Now the 32-bit items */
total_elems += prepare_item_list(DVI_item_data, OSSL_NELEM(DVI_item_data),
DVI_items, &data.buffer[total_elems]);
total_elems += prepare_item_list(JPI_item_data, OSSL_NELEM(JPI_item_data),
JPI_items, &data.buffer[total_elems]);
total_elems += prepare_item_list(RMI_item_data, OSSL_NELEM(RMI_item_data),
RMI_items, &data.buffer[total_elems]);
total_elems += prepare_item_list(SYI_item_data, OSSL_NELEM(SYI_item_data),
SYI_items, &data.buffer[total_elems]);
total_length = total_elems * sizeof(data.buffer[0]);
/* Fill data.buffer with various info bits from this process */
{
uint32_t status;
uint32_t efn;
IOSB iosb;
$DESCRIPTOR(SYSDEVICE,"SYS$SYSDEVICE:");
if ((status = sys$getdviw(EFN$C_ENF, 0, &SYSDEVICE, DVI_items,
0, 0, 0, 0, 0)) != SS$_NORMAL) {
lib$signal(status);
return 0;
}
if ((status = sys$getjpiw(EFN$C_ENF, 0, 0, JPI_items_64bit, 0, 0, 0))
!= SS$_NORMAL) {
lib$signal(status);
return 0;
}
if ((status = sys$getjpiw(EFN$C_ENF, 0, 0, JPI_items, 0, 0, 0))
!= SS$_NORMAL) {
lib$signal(status);
return 0;
}
if ((status = sys$getsyiw(EFN$C_ENF, 0, 0, SYI_items, 0, 0, 0))
!= SS$_NORMAL) {
lib$signal(status);
return 0;
}
/*
* The RMI service is a bit special, as there is no synchronous
* variant, so we MUST create an event flag to synchronise on.
*/
if ((status = lib$get_ef(&efn)) != SS$_NORMAL) {
lib$signal(status);
return 0;
}
if ((status = sys$getrmi(efn, 0, 0, RMI_items_64bit, &iosb, 0, 0))
!= SS$_NORMAL) {
lib$signal(status);
return 0;
}
if ((status = sys$synch(efn, &iosb)) != SS$_NORMAL) {
lib$signal(status);
return 0;
}
if (iosb.iosb$l_getxxi_status != SS$_NORMAL) {
lib$signal(iosb.iosb$l_getxxi_status);
return 0;
}
if ((status = sys$getrmi(efn, 0, 0, RMI_items, &iosb, 0, 0))
!= SS$_NORMAL) {
lib$signal(status);
return 0;
}
if ((status = sys$synch(efn, &iosb)) != SS$_NORMAL) {
lib$signal(status);
return 0;
}
if (iosb.iosb$l_getxxi_status != SS$_NORMAL) {
lib$signal(iosb.iosb$l_getxxi_status);
return 0;
}
if ((status = lib$free_ef(&efn)) != SS$_NORMAL) {
lib$signal(status);
return 0;
}
}
massage_JPI(JPI_items);
Fix reseeding issues of the public RAND_DRBG Reseeding is handled very differently by the classic RAND_METHOD API and the new RAND_DRBG api. These differences led to some problems when the new RAND_DRBG was made the default OpenSSL RNG. In particular, RAND_add() did not work as expected anymore. These issues are discussed on the thread '[openssl-dev] Plea for a new public OpenSSL RNG API' and in Pull Request #4328. This commit fixes the mentioned issues, introducing the following changes: - Replace the fixed size RAND_BYTES_BUFFER by a new RAND_POOL API which facilitates collecting entropy by the get_entropy() callback. - Don't use RAND_poll()/RAND_add() for collecting entropy from the get_entropy() callback anymore. Instead, replace RAND_poll() by RAND_POOL_acquire_entropy(). - Add a new function rand_drbg_restart() which tries to get the DRBG in an instantiated state by all means, regardless of the current state (uninstantiated, error, ...) the DRBG is in. If the caller provides entropy or additional input, it will be used for reseeding. - Restore the original documented behaviour of RAND_add() and RAND_poll() (namely to reseed the DRBG immediately) by a new implementation based on rand_drbg_restart(). - Add automatic error recovery from temporary failures of the entropy source to RAND_DRBG_generate() using the rand_drbg_restart() function. Reviewed-by: Paul Dale <paul.dale@oracle.com> Reviewed-by: Kurt Roeckx <kurt@roeckx.be> Reviewed-by: Rich Salz <rsalz@openssl.org> Reviewed-by: Ben Kaduk <kaduk@mit.edu> (Merged from https://github.com/openssl/openssl/pull/4328)
2017-08-31 21:16:22 +00:00
/*
* If we can't feed the requirements from the caller, we're in deep trouble.
Fix reseeding issues of the public RAND_DRBG Reseeding is handled very differently by the classic RAND_METHOD API and the new RAND_DRBG api. These differences led to some problems when the new RAND_DRBG was made the default OpenSSL RNG. In particular, RAND_add() did not work as expected anymore. These issues are discussed on the thread '[openssl-dev] Plea for a new public OpenSSL RNG API' and in Pull Request #4328. This commit fixes the mentioned issues, introducing the following changes: - Replace the fixed size RAND_BYTES_BUFFER by a new RAND_POOL API which facilitates collecting entropy by the get_entropy() callback. - Don't use RAND_poll()/RAND_add() for collecting entropy from the get_entropy() callback anymore. Instead, replace RAND_poll() by RAND_POOL_acquire_entropy(). - Add a new function rand_drbg_restart() which tries to get the DRBG in an instantiated state by all means, regardless of the current state (uninstantiated, error, ...) the DRBG is in. If the caller provides entropy or additional input, it will be used for reseeding. - Restore the original documented behaviour of RAND_add() and RAND_poll() (namely to reseed the DRBG immediately) by a new implementation based on rand_drbg_restart(). - Add automatic error recovery from temporary failures of the entropy source to RAND_DRBG_generate() using the rand_drbg_restart() function. Reviewed-by: Paul Dale <paul.dale@oracle.com> Reviewed-by: Kurt Roeckx <kurt@roeckx.be> Reviewed-by: Rich Salz <rsalz@openssl.org> Reviewed-by: Ben Kaduk <kaduk@mit.edu> (Merged from https://github.com/openssl/openssl/pull/4328)
2017-08-31 21:16:22 +00:00
*/
if (!ossl_assert(total_length >= bytes_needed)) {
ERR_raise_data(ERR_LIB_RAND, RAND_R_RANDOM_POOL_UNDERFLOW,
"Needed: %zu, Available: %zu",
bytes_needed, total_length);
return 0;
}
/*
* Try not to overfeed the pool
*/
if (total_length > bytes_remaining)
total_length = bytes_remaining;
/* We give the pessimistic value for the amount of entropy */
rand_pool_add(pool, (unsigned char *)data.buffer, total_length,
8 * total_length / ENTROPY_FACTOR);
return rand_pool_entropy_available(pool);
}
DRBG: implement a get_nonce() callback Fixes #5849 In pull request #5503 a fallback was added which adds a random nonce of security_strength/2 bits if no nonce callback is provided. This change raised the entropy requirements form 256 to 384 bit, which can cause problems on some platforms (e.g. VMS, see issue #5849). The requirements for the nonce are given in section 8.6.7 of NIST SP 800-90Ar1: A nonce may be required in the construction of a seed during instantiation in order to provide a security cushion to block certain attacks. The nonce shall be either: a) A value with at least (security_strength/2) bits of entropy, or b) A value that is expected to repeat no more often than a (security_strength/2)-bit random string would be expected to repeat. Each nonce shall be unique to the cryptographic module in which instantiation is performed, but need not be secret. When used, the nonce shall be considered to be a critical security parameter. This commit implements a nonce of type b) in order to lower the entropy requirements during instantiation back to 256 bits. The formulation "shall be unique to the cryptographic module" above implies that the nonce needs to be unique among (with high probability) among all DRBG instances in "space" and "time". We try to achieve this goal by creating a nonce of the following form nonce = app-specific-data || high-resolution-utc-timestamp || counter Where || denotes concatenation. The application specific data can be something like the process or group id of the application. A utc timestamp is used because it increases monotonically, provided the system time is synchronized. This approach may not be perfect yet for a FIPS evaluation, but it should be good enough for the moment. This commit also harmonizes the implementation of the get_nonce() and the get_additional_data() callbacks and moves the platform specific parts from rand_lib.c into rand_unix.c, rand_win.c, and rand_vms.c. Reviewed-by: Richard Levitte <levitte@openssl.org> (Merged from https://github.com/openssl/openssl/pull/5920)
2018-04-10 08:22:52 +00:00
int rand_pool_add_nonce_data(RAND_POOL *pool)
{
struct {
pid_t pid;
CRYPTO_THREAD_ID tid;
uint64_t time;
} data = { 0 };
/*
* Add process id, thread id, and a high resolution timestamp
* (where available, which is OpenVMS v8.4 and up) to ensure that
* the nonce is unique whith high probability for different process
* instances.
DRBG: implement a get_nonce() callback Fixes #5849 In pull request #5503 a fallback was added which adds a random nonce of security_strength/2 bits if no nonce callback is provided. This change raised the entropy requirements form 256 to 384 bit, which can cause problems on some platforms (e.g. VMS, see issue #5849). The requirements for the nonce are given in section 8.6.7 of NIST SP 800-90Ar1: A nonce may be required in the construction of a seed during instantiation in order to provide a security cushion to block certain attacks. The nonce shall be either: a) A value with at least (security_strength/2) bits of entropy, or b) A value that is expected to repeat no more often than a (security_strength/2)-bit random string would be expected to repeat. Each nonce shall be unique to the cryptographic module in which instantiation is performed, but need not be secret. When used, the nonce shall be considered to be a critical security parameter. This commit implements a nonce of type b) in order to lower the entropy requirements during instantiation back to 256 bits. The formulation "shall be unique to the cryptographic module" above implies that the nonce needs to be unique among (with high probability) among all DRBG instances in "space" and "time". We try to achieve this goal by creating a nonce of the following form nonce = app-specific-data || high-resolution-utc-timestamp || counter Where || denotes concatenation. The application specific data can be something like the process or group id of the application. A utc timestamp is used because it increases monotonically, provided the system time is synchronized. This approach may not be perfect yet for a FIPS evaluation, but it should be good enough for the moment. This commit also harmonizes the implementation of the get_nonce() and the get_additional_data() callbacks and moves the platform specific parts from rand_lib.c into rand_unix.c, rand_win.c, and rand_vms.c. Reviewed-by: Richard Levitte <levitte@openssl.org> (Merged from https://github.com/openssl/openssl/pull/5920)
2018-04-10 08:22:52 +00:00
*/
data.pid = getpid();
data.tid = CRYPTO_THREAD_get_current_id();
#if __CRTL_VER >= 80400000
sys$gettim_prec(&data.time);
#else
sys$gettim((void*)&data.time);
#endif
DRBG: implement a get_nonce() callback Fixes #5849 In pull request #5503 a fallback was added which adds a random nonce of security_strength/2 bits if no nonce callback is provided. This change raised the entropy requirements form 256 to 384 bit, which can cause problems on some platforms (e.g. VMS, see issue #5849). The requirements for the nonce are given in section 8.6.7 of NIST SP 800-90Ar1: A nonce may be required in the construction of a seed during instantiation in order to provide a security cushion to block certain attacks. The nonce shall be either: a) A value with at least (security_strength/2) bits of entropy, or b) A value that is expected to repeat no more often than a (security_strength/2)-bit random string would be expected to repeat. Each nonce shall be unique to the cryptographic module in which instantiation is performed, but need not be secret. When used, the nonce shall be considered to be a critical security parameter. This commit implements a nonce of type b) in order to lower the entropy requirements during instantiation back to 256 bits. The formulation "shall be unique to the cryptographic module" above implies that the nonce needs to be unique among (with high probability) among all DRBG instances in "space" and "time". We try to achieve this goal by creating a nonce of the following form nonce = app-specific-data || high-resolution-utc-timestamp || counter Where || denotes concatenation. The application specific data can be something like the process or group id of the application. A utc timestamp is used because it increases monotonically, provided the system time is synchronized. This approach may not be perfect yet for a FIPS evaluation, but it should be good enough for the moment. This commit also harmonizes the implementation of the get_nonce() and the get_additional_data() callbacks and moves the platform specific parts from rand_lib.c into rand_unix.c, rand_win.c, and rand_vms.c. Reviewed-by: Richard Levitte <levitte@openssl.org> (Merged from https://github.com/openssl/openssl/pull/5920)
2018-04-10 08:22:52 +00:00
return rand_pool_add(pool, (unsigned char *)&data, sizeof(data), 0);
}
/*
* SYS$GET_ENTROPY METHOD
* ======================
*
* This is a high entropy method based on a new system service that is
* based on getentropy() from FreeBSD 12. It's only used if available,
* and its availability is detected at run-time.
*
* We assume that this function provides full entropy random output.
*/
#define PUBLIC_VECTORS "SYS$LIBRARY:SYS$PUBLIC_VECTORS.EXE"
#define GET_ENTROPY "SYS$GET_ENTROPY"
static int get_entropy_address_flag = 0;
static int (*get_entropy_address)(void *buffer, size_t buffer_size) = NULL;
static int init_get_entropy_address(void)
{
if (get_entropy_address_flag == 0)
get_entropy_address = dlsym(dlopen(PUBLIC_VECTORS, 0), GET_ENTROPY);
get_entropy_address_flag = 1;
return get_entropy_address != NULL;
}
size_t get_entropy_method(RAND_POOL *pool)
{
/*
* The documentation says that SYS$GET_ENTROPY will give a maximum of
* 256 bytes of data.
*/
unsigned char buffer[256];
size_t bytes_needed;
size_t bytes_to_get = 0;
uint32_t status;
for (bytes_needed = rand_pool_bytes_needed(pool, 1);
bytes_needed > 0;
bytes_needed -= bytes_to_get) {
bytes_to_get =
bytes_needed > sizeof(buffer) ? sizeof(buffer) : bytes_needed;
status = get_entropy_address(buffer, bytes_to_get);
if (status == SS$_RETRY) {
/* Set to zero so the loop doesn't diminish |bytes_needed| */
bytes_to_get = 0;
/* Should sleep some amount of time */
continue;
}
if (status != SS$_NORMAL) {
lib$signal(status);
return 0;
}
rand_pool_add(pool, buffer, bytes_to_get, 8 * bytes_to_get);
}
return rand_pool_entropy_available(pool);
}
/*
* MAIN ENTROPY ACQUISITION FUNCTIONS
* ==================================
*
* These functions are called by the RAND / DRBG functions
*/
size_t rand_pool_acquire_entropy(RAND_POOL *pool)
{
if (init_get_entropy_address())
return get_entropy_method(pool);
return data_collect_method(pool);
}
DRBG: implement a get_nonce() callback Fixes #5849 In pull request #5503 a fallback was added which adds a random nonce of security_strength/2 bits if no nonce callback is provided. This change raised the entropy requirements form 256 to 384 bit, which can cause problems on some platforms (e.g. VMS, see issue #5849). The requirements for the nonce are given in section 8.6.7 of NIST SP 800-90Ar1: A nonce may be required in the construction of a seed during instantiation in order to provide a security cushion to block certain attacks. The nonce shall be either: a) A value with at least (security_strength/2) bits of entropy, or b) A value that is expected to repeat no more often than a (security_strength/2)-bit random string would be expected to repeat. Each nonce shall be unique to the cryptographic module in which instantiation is performed, but need not be secret. When used, the nonce shall be considered to be a critical security parameter. This commit implements a nonce of type b) in order to lower the entropy requirements during instantiation back to 256 bits. The formulation "shall be unique to the cryptographic module" above implies that the nonce needs to be unique among (with high probability) among all DRBG instances in "space" and "time". We try to achieve this goal by creating a nonce of the following form nonce = app-specific-data || high-resolution-utc-timestamp || counter Where || denotes concatenation. The application specific data can be something like the process or group id of the application. A utc timestamp is used because it increases monotonically, provided the system time is synchronized. This approach may not be perfect yet for a FIPS evaluation, but it should be good enough for the moment. This commit also harmonizes the implementation of the get_nonce() and the get_additional_data() callbacks and moves the platform specific parts from rand_lib.c into rand_unix.c, rand_win.c, and rand_vms.c. Reviewed-by: Richard Levitte <levitte@openssl.org> (Merged from https://github.com/openssl/openssl/pull/5920)
2018-04-10 08:22:52 +00:00
int rand_pool_add_additional_data(RAND_POOL *pool)
{
struct {
CRYPTO_THREAD_ID tid;
uint64_t time;
} data = { 0 };
/*
* Add some noise from the thread id and a high resolution timer.
* The thread id adds a little randomness if the drbg is accessed
* concurrently (which is the case for the <master> drbg).
*/
data.tid = CRYPTO_THREAD_get_current_id();
#if __CRTL_VER >= 80400000
sys$gettim_prec(&data.time);
#else
sys$gettim((void*)&data.time);
#endif
DRBG: implement a get_nonce() callback Fixes #5849 In pull request #5503 a fallback was added which adds a random nonce of security_strength/2 bits if no nonce callback is provided. This change raised the entropy requirements form 256 to 384 bit, which can cause problems on some platforms (e.g. VMS, see issue #5849). The requirements for the nonce are given in section 8.6.7 of NIST SP 800-90Ar1: A nonce may be required in the construction of a seed during instantiation in order to provide a security cushion to block certain attacks. The nonce shall be either: a) A value with at least (security_strength/2) bits of entropy, or b) A value that is expected to repeat no more often than a (security_strength/2)-bit random string would be expected to repeat. Each nonce shall be unique to the cryptographic module in which instantiation is performed, but need not be secret. When used, the nonce shall be considered to be a critical security parameter. This commit implements a nonce of type b) in order to lower the entropy requirements during instantiation back to 256 bits. The formulation "shall be unique to the cryptographic module" above implies that the nonce needs to be unique among (with high probability) among all DRBG instances in "space" and "time". We try to achieve this goal by creating a nonce of the following form nonce = app-specific-data || high-resolution-utc-timestamp || counter Where || denotes concatenation. The application specific data can be something like the process or group id of the application. A utc timestamp is used because it increases monotonically, provided the system time is synchronized. This approach may not be perfect yet for a FIPS evaluation, but it should be good enough for the moment. This commit also harmonizes the implementation of the get_nonce() and the get_additional_data() callbacks and moves the platform specific parts from rand_lib.c into rand_unix.c, rand_win.c, and rand_vms.c. Reviewed-by: Richard Levitte <levitte@openssl.org> (Merged from https://github.com/openssl/openssl/pull/5920)
2018-04-10 08:22:52 +00:00
return rand_pool_add(pool, (unsigned char *)&data, sizeof(data), 0);
}
int rand_pool_init(void)
{
return 1;
}
void rand_pool_cleanup(void)
{
}
void rand_pool_keep_random_devices_open(int keep)
{
}
#endif