diff options
Diffstat (limited to 'nss/lib/util/secasn1d.c')
| -rw-r--r-- | nss/lib/util/secasn1d.c | 45 |
1 files changed, 44 insertions, 1 deletions
diff --git a/nss/lib/util/secasn1d.c b/nss/lib/util/secasn1d.c index 797640d..e6abb5f 100644 --- a/nss/lib/util/secasn1d.c +++ b/nss/lib/util/secasn1d.c @@ -292,6 +292,17 @@ struct sec_DecoderContext_struct { sec_asn1d_state *current; sec_asn1d_parse_status status; + /* The maximum size the caller is willing to allow a single element + * to be before returning an error. + * + * In the case of an indefinite length element, this is the sum total + * of all child elements. + * + * In the case of a definite length element, this represents the maximum + * size of the top-level element. + */ + unsigned long max_element_size; + SEC_ASN1NotifyProc notify_proc; /* call before/after handling field */ void *notify_arg; /* argument to notify_proc */ PRBool during_notify; /* true during call to notify_proc */ @@ -1288,6 +1299,13 @@ sec_asn1d_prepare_for_contents(sec_asn1d_state *state) alloc_len += subitem->len; } + if (state->top->max_element_size > 0 && + alloc_len > state->top->max_element_size) { + PORT_SetError(SEC_ERROR_OUTPUT_LEN); + state->top->status = decodeError; + return; + } + item->data = (unsigned char *)sec_asn1d_zalloc(poolp, alloc_len); if (item->data == NULL) { state->top->status = decodeError; @@ -1396,6 +1414,13 @@ sec_asn1d_prepare_for_contents(sec_asn1d_state *state) if (state->dest != NULL) { item = (SECItem *)(state->dest); item->len = 0; + if (state->top->max_element_size > 0 && + state->contents_length > state->top->max_element_size) { + PORT_SetError(SEC_ERROR_OUTPUT_LEN); + state->top->status = decodeError; + return; + } + if (state->top->filter_only) { item->data = NULL; } else { @@ -2223,6 +2248,13 @@ sec_asn1d_concat_substrings(sec_asn1d_state *state) alloc_len = item_len; } + if (state->top->max_element_size > 0 && + alloc_len > state->top->max_element_size) { + PORT_SetError(SEC_ERROR_OUTPUT_LEN); + state->top->status = decodeError; + return; + } + item = (SECItem *)(state->dest); PORT_Assert(item != NULL); PORT_Assert(item->data == NULL); @@ -2726,7 +2758,7 @@ SEC_ASN1DecoderUpdate(SEC_ASN1DecoderContext *cx, #ifdef DEBUG_ASN1D_STATES printf("\nPLACE = %s, next byte = 0x%02x, %08x[%d]\n", (state->place >= 0 && state->place <= notInUse) ? place_names[state->place] : "(undefined)", - (unsigned int)((unsigned char *)buf)[consumed], + len ? (unsigned int)((unsigned char *)buf)[consumed] : 0, buf, consumed); dump_states(cx); #endif /* DEBUG_ASN1D_STATES */ @@ -3042,6 +3074,13 @@ SEC_ASN1DecoderClearNotifyProc(SEC_ASN1DecoderContext *cx) } void +SEC_ASN1DecoderSetMaximumElementSize(SEC_ASN1DecoderContext *cx, + unsigned long max_size) +{ + cx->max_element_size = max_size; +} + +void SEC_ASN1DecoderAbort(SEC_ASN1DecoderContext *cx, int error) { PORT_Assert(cx); @@ -3061,6 +3100,10 @@ SEC_ASN1Decode(PLArenaPool *poolp, void *dest, if (dcx == NULL) return SECFailure; + /* In one-shot mode, there's no possibility of streaming data beyond the + * length of len */ + SEC_ASN1DecoderSetMaximumElementSize(dcx, len); + urv = SEC_ASN1DecoderUpdate(dcx, buf, len); frv = SEC_ASN1DecoderFinish(dcx); |