From b012127a99be0c9a6d69ae2e15043176278e0438 Mon Sep 17 00:00:00 2001 From: "Dr. Stephen Henson" Date: Fri, 2 Aug 2002 18:42:40 +0000 Subject: [PATCH] Fix the ASN1 sanity check: correct header length calculation and check overflow against LONG_MAX. --- CHANGES | 6 ++++++ crypto/asn1/asn1_lib.c | 9 +++++---- 2 files changed, 11 insertions(+), 4 deletions(-) diff --git a/CHANGES b/CHANGES index f83ca8c0a0..75b88b66f7 100644 --- a/CHANGES +++ b/CHANGES @@ -1669,6 +1669,12 @@ des-cbc 3624.96k 5258.21k 5530.91k 5624.30k 5628.26k Changes between 0.9.6e and 0.9.6f [XX xxx XXXX] + *) Fix ASN1 checks. Check for overflow by comparing with LONG_MAX + and get fix the header length calculation. + [Florian Weimer , + Alon Kantor (and others), + Steve Henson] + *) Use proper error handling instead of 'assertions' in buffer overflow checks added in 0.9.6e. This prevents DoS (the assertions could call abort()). diff --git a/crypto/asn1/asn1_lib.c b/crypto/asn1/asn1_lib.c index 422685a3b4..f8b636c505 100644 --- a/crypto/asn1/asn1_lib.c +++ b/crypto/asn1/asn1_lib.c @@ -57,6 +57,7 @@ */ #include +#include #include "cryptlib.h" #include #include @@ -124,7 +125,7 @@ int ASN1_get_object(unsigned char **pp, long *plength, int *ptag, int *pclass, (int)(omax+ *pp)); #endif - if (*plength > (omax - (*pp - p))) + if (*plength > (omax - (*p - *pp))) { ASN1err(ASN1_F_ASN1_GET_OBJECT,ASN1_R_TOO_LONG); /* Set this so that even if things are not long enough @@ -141,7 +142,7 @@ err: static int asn1_get_length(unsigned char **pp, int *inf, long *rl, int max) { unsigned char *p= *pp; - long ret=0; + unsigned long ret=0; int i; if (max-- < 1) return(0); @@ -170,10 +171,10 @@ static int asn1_get_length(unsigned char **pp, int *inf, long *rl, int max) else ret=i; } - if (ret < 0) + if (ret > LONG_MAX) return 0; *pp=p; - *rl=ret; + *rl=(long)ret; return(1); } -- 2.25.1