diff options
Diffstat (limited to 'asn1.c')
| -rw-r--r-- | asn1.c | 40 |
1 files changed, 32 insertions, 8 deletions
@@ -1,7 +1,7 @@ /* asn1.c * Routines for ASN.1 BER dissection * - * $Id: asn1.c,v 1.18 2003/04/28 00:31:26 guy Exp $ + * $Id: asn1.c,v 1.19 2003/05/10 02:00:41 guy Exp $ * * Ethereal - Network traffic analyzer * By Gerald Combs <gerald@ethereal.com> @@ -607,20 +607,42 @@ asn1_bits_decode ( ASN1_SCK *asn1, int enc_len, guchar **bits, int eoc; guchar *ptr; - eoc = asn1->offset + enc_len; *bits = NULL; ret = asn1_octet_decode (asn1, unused); if (ret != ASN1_ERR_NOERROR) return ret; *len = 0; - ptr = *bits = g_malloc(enc_len); + + /* + * First, make sure the entire string is in the tvbuff, and throw + * an exception if it isn't. If the length is bogus, this should + * keep us from trying to allocate an immensely large buffer. + * (It won't help if the length is *valid* but immensely large, + * but that's another matter; in any case, that would happen only + * if we had an immensely large tvbuff....) + */ + if (enc_len != 0) { + tvb_ensure_bytes_exist(asn1->tvb, asn1->offset, enc_len); + *bits = g_malloc (enc_len); + } else { + /* + * If the length is 0, we allocate a 1-byte buffer, as + * "g_malloc()" returns NULL if passed 0 as an argument, + * and our caller expects us to return a pointer to a + * buffer. + */ + *bits = g_malloc (1); + } + + eoc = asn1->offset + enc_len; + ptr = *bits; while (asn1->offset < eoc) { ret = asn1_octet_decode (asn1, (guchar *)ptr++); if (ret != ASN1_ERR_NOERROR) { g_free(*bits); *bits = NULL; return ret; - } + } } *len = ptr - *bits; return ASN1_ERR_NOERROR; @@ -654,10 +676,11 @@ asn1_string_value_decode ( ASN1_SCK *asn1, int enc_len, guchar **octets) * an exception if it isn't. If the length is bogus, this should * keep us from trying to allocate an immensely large buffer. * (It won't help if the length is *valid* but immensely large, - * but that's another matter.) + * but that's another matter; in any case, that would happen only + * if we had an immensely large tvbuff....) */ if (enc_len != 0) { - tvb_ensure_bytes_exist(asn1->tvb, asn1->offset, enc_len); + tvb_ensure_bytes_exist(asn1->tvb, asn1->offset, enc_len); *octets = g_malloc (enc_len); } else { /* @@ -821,10 +844,11 @@ asn1_oid_value_decode ( ASN1_SCK *asn1, int enc_len, subid_t **oid, guint *len) * an exception if it isn't. If the length is bogus, this should * keep us from trying to allocate an immensely large buffer. * (It won't help if the length is *valid* but immensely large, - * but that's another matter.) + * but that's another matter; in any case, that would happen only + * if we had an immensely large tvbuff....) */ if (enc_len != 0) - tvb_ensure_bytes_exist(asn1->tvb, asn1->offset, enc_len); + tvb_ensure_bytes_exist(asn1->tvb, asn1->offset, enc_len); eoc = asn1->offset + enc_len; |