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Remove ssh-keygen's moduli screen -Omemory option.

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This vaguely made sense 20 years ago, but these days you'd be hard
pressed to *find* a machine small enough to not support the maximum
(127MB), and no one is screening moduli on such machines anyway,
so just use the max.  This also fixes Coverity CID 470522 by deleting
code in question.  "kill it with fire" djm@.
This commit is contained in:
dtucker
2025-05-24 03:39:48 +00:00
parent 4a91b963c3
commit 3bab43df5a
1 changed files with 7 additions and 52 deletions
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59
usr.bin/ssh/moduli.c
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@@ -1,4 +1,4 @@
/* $OpenBSD: moduli.c,v 1.39 2023/03/02 06:41:56 dtucker Exp $ */
/* $OpenBSD: moduli.c,v 1.40 2025/05/24 03:39:48 dtucker Exp $ */
/*
* Copyright 1994 Phil Karn <karn@qualcomm.com>
* Copyright 1996-1998, 2003 William Allen Simpson <wsimpson@greendragon.com>
@@ -81,13 +81,6 @@
#define SHIFT_MEGABYTE (20)
#define SHIFT_MEGAWORD (SHIFT_MEGABYTE-SHIFT_BYTE)
/*
* Using virtual memory can cause thrashing. This should be the largest
* number that is supported without a large amount of disk activity --
* that would increase the run time from hours to days or weeks!
*/
#define LARGE_MINIMUM (8UL) /* megabytes */
/*
* Do not increase this number beyond the unsigned integer bit size.
* Due to a multiple of 4, it must be LESS than 128 (yielding 2**30 bits).
@@ -136,7 +129,7 @@ static u_int32_t *LargeSieve, largewords, largetries, largenumbers;
static u_int32_t largebits, largememory; /* megabytes */
static BIGNUM *largebase;
int gen_candidates(FILE *, u_int32_t, u_int32_t, BIGNUM *);
int gen_candidates(FILE *, u_int32_t, BIGNUM *);
int prime_test(FILE *, FILE *, u_int32_t, u_int32_t, char *, unsigned long,
unsigned long);
@@ -236,7 +229,7 @@ sieve_large(u_int32_t s32)
* The list is checked against small known primes (less than 2**30).
*/
int
gen_candidates(FILE *out, u_int32_t memory, u_int32_t power, BIGNUM *start)
gen_candidates(FILE *out, u_int32_t power, BIGNUM *start)
{
BIGNUM *q;
u_int32_t j, r, s, t;
@@ -246,15 +239,6 @@ gen_candidates(FILE *out, u_int32_t memory, u_int32_t power, BIGNUM *start)
u_int32_t i;
int ret = 0;
largememory = memory;
if (memory != 0 &&
(memory < LARGE_MINIMUM || memory > LARGE_MAXIMUM)) {
error("Invalid memory amount (min %ld, max %ld)",
LARGE_MINIMUM, LARGE_MAXIMUM);
return (-1);
}
/*
* Set power to the length in bits of the prime to be generated.
* This is changed to 1 less than the desired safe prime moduli p.
@@ -268,33 +252,9 @@ gen_candidates(FILE *out, u_int32_t memory, u_int32_t power, BIGNUM *start)
}
power--; /* decrement before squaring */
/*
* The density of ordinary primes is on the order of 1/bits, so the
* density of safe primes should be about (1/bits)**2. Set test range
* to something well above bits**2 to be reasonably sure (but not
* guaranteed) of catching at least one safe prime.
*/
largewords = ((power * power) >> (SHIFT_WORD - TEST_POWER));
/*
* Need idea of how much memory is available. We don't have to use all
* of it.
*/
if (largememory > LARGE_MAXIMUM) {
logit("Limited memory: %u MB; limit %lu MB",
largememory, LARGE_MAXIMUM);
largememory = LARGE_MAXIMUM;
}
if (largewords <= (largememory << SHIFT_MEGAWORD)) {
logit("Increased memory: %u MB; need %u bytes",
largememory, (largewords << SHIFT_BYTE));
largewords = (largememory << SHIFT_MEGAWORD);
} else if (largememory > 0) {
logit("Decreased memory: %u MB; want %u bytes",
largememory, (largewords << SHIFT_BYTE));
largewords = (largememory << SHIFT_MEGAWORD);
}
/* Always use the maximum amount of memory supported by the algorithm. */
largememory = LARGE_MAXIMUM;
largewords = (largememory << SHIFT_MEGAWORD);
TinySieve = xcalloc(tinywords, sizeof(u_int32_t));
tinybits = tinywords << SHIFT_WORD;
@@ -302,12 +262,7 @@ gen_candidates(FILE *out, u_int32_t memory, u_int32_t power, BIGNUM *start)
SmallSieve = xcalloc(smallwords, sizeof(u_int32_t));
smallbits = smallwords << SHIFT_WORD;
/*
* dynamically determine available memory
*/
while ((LargeSieve = calloc(largewords, sizeof(u_int32_t))) == NULL)
largewords -= (1L << (SHIFT_MEGAWORD - 2)); /* 1/4 MB chunks */
LargeSieve = xcalloc(largewords, sizeof(u_int32_t));
largebits = largewords << SHIFT_WORD;
largenumbers = largebits * 2; /* even numbers excluded */