diff options
Diffstat (limited to 'crypto/openssh/dh.c')
| -rw-r--r-- | crypto/openssh/dh.c | 39 |
1 files changed, 30 insertions, 9 deletions
diff --git a/crypto/openssh/dh.c b/crypto/openssh/dh.c index 044d869..f6ef05c 100644 --- a/crypto/openssh/dh.c +++ b/crypto/openssh/dh.c @@ -1,3 +1,4 @@ +/* $OpenBSD: dh.c,v 1.42 2006/08/03 03:34:42 deraadt Exp $ */ /* * Copyright (c) 2000 Niels Provos. All rights reserved. * @@ -23,17 +24,17 @@ */ #include "includes.h" -RCSID("$OpenBSD: dh.c,v 1.31 2004/08/04 10:37:52 djm Exp $"); -#include "xmalloc.h" +#include <sys/param.h> #include <openssl/bn.h> #include <openssl/dh.h> -#include <openssl/evp.h> -#include "buffer.h" -#include "cipher.h" -#include "kex.h" +#include <stdarg.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> + #include "dh.h" #include "pathnames.h" #include "log.h" @@ -44,9 +45,11 @@ parse_prime(int linenum, char *line, struct dhgroup *dhg) { char *cp, *arg; char *strsize, *gen, *prime; + const char *errstr = NULL; cp = line; - arg = strdelim(&cp); + if ((arg = strdelim(&cp)) == NULL) + return 0; /* Ignore leading whitespace */ if (*arg == '\0') arg = strdelim(&cp); @@ -67,7 +70,8 @@ parse_prime(int linenum, char *line, struct dhgroup *dhg) goto fail; strsize = strsep(&cp, " "); /* size */ if (cp == NULL || *strsize == '\0' || - (dhg->size = atoi(strsize)) == 0) + (dhg->size = (u_int)strtonum(strsize, 0, 64*1024, &errstr)) == 0 || + errstr) goto fail; /* The whole group is one bit larger */ dhg->size++; @@ -178,19 +182,36 @@ dh_pub_is_valid(DH *dh, BIGNUM *dh_pub) int i; int n = BN_num_bits(dh_pub); int bits_set = 0; + BIGNUM *tmp; if (dh_pub->neg) { logit("invalid public DH value: negativ"); return 0; } + if (BN_cmp(dh_pub, BN_value_one()) != 1) { /* pub_exp <= 1 */ + logit("invalid public DH value: <= 1"); + return 0; + } + + if ((tmp = BN_new()) == NULL) + return (-1); + if (!BN_sub(tmp, dh->p, BN_value_one()) || + BN_cmp(dh_pub, tmp) != -1) { /* pub_exp > p-2 */ + BN_clear_free(tmp); + logit("invalid public DH value: >= p-1"); + return 0; + } + BN_clear_free(tmp); + for (i = 0; i <= n; i++) if (BN_is_bit_set(dh_pub, i)) bits_set++; debug2("bits set: %d/%d", bits_set, BN_num_bits(dh->p)); /* if g==2 and bits_set==1 then computing log_g(dh_pub) is trivial */ - if (bits_set > 1 && (BN_cmp(dh_pub, dh->p) == -1)) + if (bits_set > 1) return 1; + logit("invalid public DH value (%d/%d)", bits_set, BN_num_bits(dh->p)); return 0; } |
