937 lines
23 KiB
C
937 lines
23 KiB
C
// Copyright (c) 2014, Google Inc.
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// SPDX-License-Identifier: ISC
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#include <openssl/asn1.h>
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#include <openssl/bytestring.h>
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#include <openssl/mem.h>
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#include <assert.h>
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#ifndef __STDC_FORMAT_MACROS
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#define __STDC_FORMAT_MACROS
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#endif
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#include <ctype.h>
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#include <inttypes.h>
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#include <string.h>
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#include "../asn1/internal.h"
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#include "../internal.h"
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#include "internal.h"
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void CBS_init(CBS *cbs, const uint8_t *data, size_t len) {
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cbs->data = data;
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cbs->len = len;
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}
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static int cbs_get(CBS *cbs, const uint8_t **p, size_t n) {
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if (cbs->len < n) {
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return 0;
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}
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*p = cbs->data;
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cbs->data += n;
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cbs->len -= n;
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return 1;
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}
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int CBS_skip(CBS *cbs, size_t len) {
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const uint8_t *dummy;
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return cbs_get(cbs, &dummy, len);
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}
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const uint8_t *CBS_data(const CBS *cbs) { return cbs->data; }
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size_t CBS_len(const CBS *cbs) { return cbs->len; }
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int CBS_stow(const CBS *cbs, uint8_t **out_ptr, size_t *out_len) {
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OPENSSL_free(*out_ptr);
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*out_ptr = NULL;
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*out_len = 0;
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if (cbs->len == 0) {
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return 1;
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}
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*out_ptr = OPENSSL_memdup(cbs->data, cbs->len);
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if (*out_ptr == NULL) {
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return 0;
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}
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*out_len = cbs->len;
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return 1;
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}
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int CBS_strdup(const CBS *cbs, char **out_ptr) {
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if (*out_ptr != NULL) {
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OPENSSL_free(*out_ptr);
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}
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*out_ptr = OPENSSL_strndup((const char *)cbs->data, cbs->len);
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return (*out_ptr != NULL);
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}
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int CBS_contains_zero_byte(const CBS *cbs) {
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return OPENSSL_memchr(cbs->data, 0, cbs->len) != NULL;
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}
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int CBS_mem_equal(const CBS *cbs, const uint8_t *data, size_t len) {
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if (len != cbs->len) {
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return 0;
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}
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return CRYPTO_memcmp(cbs->data, data, len) == 0;
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}
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static int cbs_get_u(CBS *cbs, uint64_t *out, size_t len) {
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uint64_t result = 0;
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const uint8_t *data;
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if (!cbs_get(cbs, &data, len)) {
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return 0;
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}
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for (size_t i = 0; i < len; i++) {
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result <<= 8;
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result |= data[i];
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}
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*out = result;
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return 1;
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}
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int CBS_get_u8(CBS *cbs, uint8_t *out) {
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const uint8_t *v;
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if (!cbs_get(cbs, &v, 1)) {
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return 0;
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}
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*out = *v;
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return 1;
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}
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int CBS_get_u16(CBS *cbs, uint16_t *out) {
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uint64_t v;
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if (!cbs_get_u(cbs, &v, 2)) {
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return 0;
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}
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*out = v;
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return 1;
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}
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int CBS_get_u16le(CBS *cbs, uint16_t *out) {
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if (!CBS_get_u16(cbs, out)) {
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return 0;
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}
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*out = CRYPTO_bswap2(*out);
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return 1;
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}
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int CBS_get_u24(CBS *cbs, uint32_t *out) {
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uint64_t v;
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if (!cbs_get_u(cbs, &v, 3)) {
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return 0;
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}
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*out = (uint32_t)v;
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return 1;
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}
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int CBS_get_u32(CBS *cbs, uint32_t *out) {
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uint64_t v;
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if (!cbs_get_u(cbs, &v, 4)) {
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return 0;
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}
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*out = (uint32_t)v;
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return 1;
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}
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int CBS_get_u32le(CBS *cbs, uint32_t *out) {
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if (!CBS_get_u32(cbs, out)) {
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return 0;
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}
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*out = CRYPTO_bswap4(*out);
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return 1;
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}
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int CBS_get_u64(CBS *cbs, uint64_t *out) { return cbs_get_u(cbs, out, 8); }
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int CBS_get_u64le(CBS *cbs, uint64_t *out) {
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if (!cbs_get_u(cbs, out, 8)) {
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return 0;
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}
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*out = CRYPTO_bswap8(*out);
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return 1;
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}
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int CBS_get_last_u8(CBS *cbs, uint8_t *out) {
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if (cbs->len == 0) {
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return 0;
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}
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*out = cbs->data[cbs->len - 1];
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cbs->len--;
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return 1;
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}
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int CBS_get_bytes(CBS *cbs, CBS *out, size_t len) {
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const uint8_t *v;
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if (!cbs_get(cbs, &v, len)) {
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return 0;
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}
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CBS_init(out, v, len);
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return 1;
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}
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int CBS_copy_bytes(CBS *cbs, uint8_t *out, size_t len) {
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const uint8_t *v;
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if (!cbs_get(cbs, &v, len)) {
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return 0;
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}
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OPENSSL_memcpy(out, v, len);
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return 1;
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}
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static int cbs_get_length_prefixed(CBS *cbs, CBS *out, size_t len_len) {
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uint64_t len;
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if (!cbs_get_u(cbs, &len, len_len)) {
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return 0;
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}
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// If |len_len| <= 3 then we know that |len| will fit into a |size_t|, even on
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// 32-bit systems.
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assert(len_len <= 3);
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return CBS_get_bytes(cbs, out, len);
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}
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int CBS_get_u8_length_prefixed(CBS *cbs, CBS *out) {
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return cbs_get_length_prefixed(cbs, out, 1);
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}
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int CBS_get_u16_length_prefixed(CBS *cbs, CBS *out) {
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return cbs_get_length_prefixed(cbs, out, 2);
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}
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int CBS_get_u24_length_prefixed(CBS *cbs, CBS *out) {
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return cbs_get_length_prefixed(cbs, out, 3);
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}
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int CBS_get_until_first(CBS *cbs, CBS *out, uint8_t c) {
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const uint8_t *split = OPENSSL_memchr(CBS_data(cbs), c, CBS_len(cbs));
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if (split == NULL) {
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return 0;
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}
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return CBS_get_bytes(cbs, out, split - CBS_data(cbs));
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}
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int CBS_get_u64_decimal(CBS *cbs, uint64_t *out) {
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uint64_t v = 0;
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int seen_digit = 0;
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while (CBS_len(cbs) != 0) {
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uint8_t c = CBS_data(cbs)[0];
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if (!OPENSSL_isdigit(c)) {
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break;
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}
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CBS_skip(cbs, 1);
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if ( // Forbid stray leading zeros.
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(v == 0 && seen_digit) ||
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// Check for overflow.
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v > UINT64_MAX / 10 || //
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v * 10 > UINT64_MAX - (c - '0')) {
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return 0;
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}
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v = v * 10 + (c - '0');
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seen_digit = 1;
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}
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*out = v;
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return seen_digit;
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}
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// parse_base128_integer reads a big-endian base-128 integer from |cbs| and sets
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// |*out| to the result. This is the encoding used in DER for both high tag
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// number form and OID components.
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static int parse_base128_integer(CBS *cbs, uint64_t *out) {
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uint64_t v = 0;
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uint8_t b;
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do {
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if (!CBS_get_u8(cbs, &b)) {
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return 0;
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}
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if ((v >> (64 - 7)) != 0) {
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// The value is too large.
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return 0;
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}
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if (v == 0 && b == 0x80) {
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// The value must be minimally encoded.
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return 0;
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}
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v = (v << 7) | (b & 0x7f);
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// Values end at an octet with the high bit cleared.
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} while (b & 0x80);
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*out = v;
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return 1;
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}
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static int parse_asn1_tag(CBS *cbs, CBS_ASN1_TAG *out, int universal_tag_ok) {
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uint8_t tag_byte;
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if (!CBS_get_u8(cbs, &tag_byte)) {
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return 0;
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}
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// ITU-T X.690 section 8.1.2.3 specifies the format for identifiers with a tag
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// number no greater than 30.
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//
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// If the number portion is 31 (0x1f, the largest value that fits in the
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// allotted bits), then the tag is more than one byte long and the
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// continuation bytes contain the tag number.
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CBS_ASN1_TAG tag = ((CBS_ASN1_TAG)tag_byte & 0xe0) << CBS_ASN1_TAG_SHIFT;
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CBS_ASN1_TAG tag_number = tag_byte & 0x1f;
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if (tag_number == 0x1f) {
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uint64_t v;
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if (!parse_base128_integer(cbs, &v) ||
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// Check the tag number is within our supported bounds.
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v > CBS_ASN1_TAG_NUMBER_MASK ||
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// Small tag numbers should have used low tag number form, even in BER.
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v < 0x1f) {
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return 0;
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}
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tag_number = (CBS_ASN1_TAG)v;
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}
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tag |= tag_number;
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// Tag [UNIVERSAL 0] is reserved for use by the encoding. Reject it here to
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// avoid some ambiguity around ANY values and BER indefinite-length EOCs. See
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// https://crbug.com/boringssl/455.
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if (!universal_tag_ok && (tag & ~CBS_ASN1_CONSTRUCTED) == 0) {
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return 0;
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}
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*out = tag;
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return 1;
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}
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int cbs_get_any_asn1_element(CBS *cbs, CBS *out, CBS_ASN1_TAG *out_tag,
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size_t *out_header_len, int *out_ber_found,
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int *out_indefinite, int ber_ok, int universal_tag_ok) {
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CBS header = *cbs;
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CBS throwaway;
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if (out == NULL) {
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out = &throwaway;
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}
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if (ber_ok) {
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*out_ber_found = 0;
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*out_indefinite = 0;
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} else {
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assert(out_ber_found == NULL);
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assert(out_indefinite == NULL);
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}
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CBS_ASN1_TAG tag;
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if (!parse_asn1_tag(&header, &tag, universal_tag_ok)) {
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return 0;
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}
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if (out_tag != NULL) {
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*out_tag = tag;
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}
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uint8_t length_byte;
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if (!CBS_get_u8(&header, &length_byte)) {
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return 0;
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}
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size_t header_len = CBS_len(cbs) - CBS_len(&header);
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size_t len;
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// The format for the length encoding is specified in ITU-T X.690 section
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// 8.1.3.
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if ((length_byte & 0x80) == 0) {
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// Short form length.
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len = ((size_t)length_byte) + header_len;
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if (out_header_len != NULL) {
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*out_header_len = header_len;
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}
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} else {
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// The high bit indicate that this is the long form, while the next 7 bits
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// encode the number of subsequent octets used to encode the length (ITU-T
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// X.690 clause 8.1.3.5.b).
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const size_t num_bytes = length_byte & 0x7f;
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uint64_t len64;
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if (ber_ok && (tag & CBS_ASN1_CONSTRUCTED) != 0 && num_bytes == 0) {
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// indefinite length
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if (out_header_len != NULL) {
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*out_header_len = header_len;
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}
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*out_ber_found = 1;
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*out_indefinite = 1;
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return CBS_get_bytes(cbs, out, header_len);
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}
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// ITU-T X.690 clause 8.1.3.5.c specifies that the value 0xff shall not be
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// used as the first byte of the length. If this parser encounters that
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// value, num_bytes will be parsed as 127, which will fail this check.
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if (num_bytes == 0 || num_bytes > 4) {
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return 0;
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}
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if (!cbs_get_u(&header, &len64, num_bytes)) {
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return 0;
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}
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// ITU-T X.690 section 10.1 (DER length forms) requires encoding the
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// length with the minimum number of octets. BER could, technically, have
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// 125 superfluous zero bytes. We do not attempt to handle that and still
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// require that the length fit in a |uint32_t| for BER.
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if (len64 < 128) {
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// Length should have used short-form encoding.
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if (ber_ok) {
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*out_ber_found = 1;
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} else {
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return 0;
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}
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}
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if ((len64 >> ((num_bytes - 1) * 8)) == 0) {
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// Length should have been at least one byte shorter.
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if (ber_ok) {
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*out_ber_found = 1;
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} else {
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return 0;
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}
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}
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len = len64;
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if (len + header_len + num_bytes < len) {
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// Overflow.
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return 0;
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}
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len += header_len + num_bytes;
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if (out_header_len != NULL) {
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*out_header_len = header_len + num_bytes;
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}
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}
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return CBS_get_bytes(cbs, out, len);
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}
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int CBS_get_any_asn1(CBS *cbs, CBS *out, CBS_ASN1_TAG *out_tag) {
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size_t header_len;
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if (!CBS_get_any_asn1_element(cbs, out, out_tag, &header_len)) {
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return 0;
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}
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if (!CBS_skip(out, header_len)) {
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assert(0);
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return 0;
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}
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return 1;
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}
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int CBS_get_any_asn1_element(CBS *cbs, CBS *out, CBS_ASN1_TAG *out_tag,
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size_t *out_header_len) {
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return cbs_get_any_asn1_element(cbs, out, out_tag, out_header_len, NULL, NULL,
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/*ber_ok=*/0, /*universal_tag_ok=*/0);
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}
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int CBS_get_any_ber_asn1_element(CBS *cbs, CBS *out, CBS_ASN1_TAG *out_tag,
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size_t *out_header_len, int *out_ber_found,
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int *out_indefinite) {
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int ber_found_temp;
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return cbs_get_any_asn1_element(
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cbs, out, out_tag, out_header_len,
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out_ber_found ? out_ber_found : &ber_found_temp, out_indefinite,
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/*ber_ok=*/1, /*universal_tag_ok=*/0);
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}
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static int cbs_get_asn1(CBS *cbs, CBS *out, CBS_ASN1_TAG tag_value,
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int skip_header) {
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size_t header_len;
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CBS_ASN1_TAG tag;
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CBS throwaway;
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if (out == NULL) {
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out = &throwaway;
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}
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if (!CBS_get_any_asn1_element(cbs, out, &tag, &header_len) ||
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tag != tag_value) {
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return 0;
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}
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if (skip_header && !CBS_skip(out, header_len)) {
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assert(0);
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return 0;
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}
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return 1;
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}
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int CBS_get_asn1(CBS *cbs, CBS *out, CBS_ASN1_TAG tag_value) {
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return cbs_get_asn1(cbs, out, tag_value, 1 /* skip header */);
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}
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int CBS_get_asn1_element(CBS *cbs, CBS *out, CBS_ASN1_TAG tag_value) {
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return cbs_get_asn1(cbs, out, tag_value, 0 /* include header */);
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}
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int CBS_peek_asn1_tag(const CBS *cbs, CBS_ASN1_TAG tag_value) {
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CBS copy = *cbs;
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CBS_ASN1_TAG actual_tag;
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return parse_asn1_tag(©, &actual_tag, /*universal_tag_ok=*/0) && tag_value == actual_tag;
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}
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int CBS_get_asn1_uint64(CBS *cbs, uint64_t *out) {
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CBS bytes;
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if (!CBS_get_asn1(cbs, &bytes, CBS_ASN1_INTEGER) ||
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!CBS_is_unsigned_asn1_integer(&bytes)) {
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return 0;
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}
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*out = 0;
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const uint8_t *data = CBS_data(&bytes);
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size_t len = CBS_len(&bytes);
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for (size_t i = 0; i < len; i++) {
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if ((*out >> 56) != 0) {
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// Too large to represent as a uint64_t.
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return 0;
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}
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*out <<= 8;
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*out |= data[i];
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}
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return 1;
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}
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int CBS_get_asn1_int64(CBS *cbs, int64_t *out) {
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int is_negative;
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CBS bytes;
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if (!CBS_get_asn1(cbs, &bytes, CBS_ASN1_INTEGER) ||
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!CBS_is_valid_asn1_integer(&bytes, &is_negative)) {
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return 0;
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}
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const uint8_t *data = CBS_data(&bytes);
|
|
const size_t len = CBS_len(&bytes);
|
|
if (len > sizeof(int64_t)) {
|
|
return 0;
|
|
}
|
|
uint8_t sign_extend[sizeof(int64_t)];
|
|
memset(sign_extend, is_negative ? 0xff : 0, sizeof(sign_extend));
|
|
// GCC 12/13 report `stringop-overflow` on the following line
|
|
// without additional condition: `i < sizeof(int64_t)`
|
|
for (size_t i = 0; i < len && i < sizeof(int64_t); i++) {
|
|
// `data` is big-endian.
|
|
// Values are always shifted toward the "little" end.
|
|
#ifdef OPENSSL_BIG_ENDIAN
|
|
// Bytes are written starting at the highest index.
|
|
sign_extend[sizeof(sign_extend) - i - 1] = data[len - i - 1];
|
|
#else
|
|
// Bytes are written starting at the lowest index.
|
|
sign_extend[i] = data[len - i - 1];
|
|
#endif
|
|
}
|
|
|
|
memcpy(out, sign_extend, sizeof(sign_extend));
|
|
return 1;
|
|
}
|
|
|
|
int CBS_get_asn1_bool(CBS *cbs, int *out) {
|
|
CBS bytes;
|
|
if (!CBS_get_asn1(cbs, &bytes, CBS_ASN1_BOOLEAN) || CBS_len(&bytes) != 1) {
|
|
return 0;
|
|
}
|
|
|
|
const uint8_t value = *CBS_data(&bytes);
|
|
if (value != 0 && value != 0xff) {
|
|
return 0;
|
|
}
|
|
|
|
*out = !!value;
|
|
return 1;
|
|
}
|
|
|
|
int CBS_get_optional_asn1(CBS *cbs, CBS *out, int *out_present,
|
|
CBS_ASN1_TAG tag) {
|
|
int present = 0;
|
|
|
|
if (CBS_peek_asn1_tag(cbs, tag)) {
|
|
if (!CBS_get_asn1(cbs, out, tag)) {
|
|
return 0;
|
|
}
|
|
present = 1;
|
|
}
|
|
|
|
if (out_present != NULL) {
|
|
*out_present = present;
|
|
}
|
|
|
|
return 1;
|
|
}
|
|
|
|
int CBS_get_optional_asn1_octet_string(CBS *cbs, CBS *out, int *out_present,
|
|
CBS_ASN1_TAG tag) {
|
|
CBS child;
|
|
int present;
|
|
if (!CBS_get_optional_asn1(cbs, &child, &present, tag)) {
|
|
return 0;
|
|
}
|
|
if (present) {
|
|
assert(out);
|
|
if (!CBS_get_asn1(&child, out, CBS_ASN1_OCTETSTRING) ||
|
|
CBS_len(&child) != 0) {
|
|
return 0;
|
|
}
|
|
} else {
|
|
CBS_init(out, NULL, 0);
|
|
}
|
|
if (out_present) {
|
|
*out_present = present;
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
int CBS_get_optional_asn1_uint64(CBS *cbs, uint64_t *out, CBS_ASN1_TAG tag,
|
|
uint64_t default_value) {
|
|
CBS child;
|
|
int present;
|
|
if (!CBS_get_optional_asn1(cbs, &child, &present, tag)) {
|
|
return 0;
|
|
}
|
|
if (present) {
|
|
if (!CBS_get_asn1_uint64(&child, out) || CBS_len(&child) != 0) {
|
|
return 0;
|
|
}
|
|
} else {
|
|
*out = default_value;
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
int CBS_get_optional_asn1_bool(CBS *cbs, int *out, CBS_ASN1_TAG tag,
|
|
int default_value) {
|
|
CBS child, child2;
|
|
int present;
|
|
if (!CBS_get_optional_asn1(cbs, &child, &present, tag)) {
|
|
return 0;
|
|
}
|
|
if (present) {
|
|
uint8_t boolean;
|
|
|
|
if (!CBS_get_asn1(&child, &child2, CBS_ASN1_BOOLEAN) ||
|
|
CBS_len(&child2) != 1 || CBS_len(&child) != 0) {
|
|
return 0;
|
|
}
|
|
|
|
boolean = CBS_data(&child2)[0];
|
|
if (boolean == 0) {
|
|
*out = 0;
|
|
} else if (boolean == 0xff) {
|
|
*out = 1;
|
|
} else {
|
|
return 0;
|
|
}
|
|
} else {
|
|
*out = default_value;
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
int CBS_is_valid_asn1_bitstring(const CBS *cbs) {
|
|
CBS in = *cbs;
|
|
uint8_t num_unused_bits;
|
|
if (!CBS_get_u8(&in, &num_unused_bits) || num_unused_bits > 7) {
|
|
return 0;
|
|
}
|
|
|
|
if (num_unused_bits == 0) {
|
|
return 1;
|
|
}
|
|
|
|
// All num_unused_bits bits must exist and be zeros.
|
|
uint8_t last;
|
|
if (!CBS_get_last_u8(&in, &last) ||
|
|
(last & ((1 << num_unused_bits) - 1)) != 0) {
|
|
return 0;
|
|
}
|
|
|
|
return 1;
|
|
}
|
|
|
|
int CBS_asn1_bitstring_has_bit(const CBS *cbs, unsigned bit) {
|
|
if (!CBS_is_valid_asn1_bitstring(cbs)) {
|
|
return 0;
|
|
}
|
|
|
|
const unsigned byte_num = (bit >> 3) + 1;
|
|
const unsigned bit_num = 7 - (bit & 7);
|
|
|
|
// Unused bits are zero, and this function does not distinguish between
|
|
// missing and unset bits. Thus it is sufficient to do a byte-level length
|
|
// check.
|
|
return byte_num < CBS_len(cbs) &&
|
|
(CBS_data(cbs)[byte_num] & (1 << bit_num)) != 0;
|
|
}
|
|
|
|
int CBS_is_valid_asn1_integer(const CBS *cbs, int *out_is_negative) {
|
|
CBS copy = *cbs;
|
|
uint8_t first_byte, second_byte;
|
|
if (!CBS_get_u8(©, &first_byte)) {
|
|
return 0; // INTEGERs may not be empty.
|
|
}
|
|
if (out_is_negative != NULL) {
|
|
*out_is_negative = (first_byte & 0x80) != 0;
|
|
}
|
|
if (!CBS_get_u8(©, &second_byte)) {
|
|
return 1; // One byte INTEGERs are always minimal.
|
|
}
|
|
if ((first_byte == 0x00 && (second_byte & 0x80) == 0) ||
|
|
(first_byte == 0xff && (second_byte & 0x80) != 0)) {
|
|
return 0; // The value is minimal iff the first 9 bits are not all equal.
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
int CBS_is_unsigned_asn1_integer(const CBS *cbs) {
|
|
int is_negative;
|
|
return CBS_is_valid_asn1_integer(cbs, &is_negative) && !is_negative;
|
|
}
|
|
|
|
static int add_decimal(CBB *out, uint64_t v) {
|
|
char buf[DECIMAL_SIZE(uint64_t) + 1];
|
|
snprintf(buf, sizeof(buf), "%" PRIu64, v);
|
|
return CBB_add_bytes(out, (const uint8_t *)buf, strlen(buf));
|
|
}
|
|
|
|
int CBS_is_valid_asn1_oid(const CBS *cbs) {
|
|
if (CBS_len(cbs) == 0) {
|
|
return 0; // OID encodings cannot be empty.
|
|
}
|
|
|
|
CBS copy = *cbs;
|
|
uint8_t v, prev = 0;
|
|
while (CBS_get_u8(©, &v)) {
|
|
// OID encodings are a sequence of minimally-encoded base-128 integers (see
|
|
// |parse_base128_integer|). If |prev|'s MSB was clear, it was the last byte
|
|
// of an integer (or |v| is the first byte). |v| is then the first byte of
|
|
// the next integer. If first byte of an integer is 0x80, it is not
|
|
// minimally-encoded.
|
|
if ((prev & 0x80) == 0 && v == 0x80) {
|
|
return 0;
|
|
}
|
|
prev = v;
|
|
}
|
|
|
|
// The last byte should must end an integer encoding.
|
|
return (prev & 0x80) == 0;
|
|
}
|
|
|
|
char *CBS_asn1_oid_to_text(const CBS *cbs) {
|
|
CBB cbb;
|
|
if (!CBB_init(&cbb, 32)) {
|
|
goto err;
|
|
}
|
|
|
|
CBS copy = *cbs;
|
|
// The first component is 40 * value1 + value2, where value1 is 0, 1, or 2.
|
|
uint64_t v;
|
|
if (!parse_base128_integer(©, &v)) {
|
|
goto err;
|
|
}
|
|
|
|
if (v >= 80) {
|
|
if (!CBB_add_bytes(&cbb, (const uint8_t *)"2.", 2) ||
|
|
!add_decimal(&cbb, v - 80)) {
|
|
goto err;
|
|
}
|
|
} else if (!add_decimal(&cbb, v / 40) || !CBB_add_u8(&cbb, '.') ||
|
|
!add_decimal(&cbb, v % 40)) {
|
|
goto err;
|
|
}
|
|
|
|
while (CBS_len(©) != 0) {
|
|
if (!parse_base128_integer(©, &v) || !CBB_add_u8(&cbb, '.') ||
|
|
!add_decimal(&cbb, v)) {
|
|
goto err;
|
|
}
|
|
}
|
|
|
|
uint8_t *txt;
|
|
size_t txt_len;
|
|
if (!CBB_add_u8(&cbb, '\0') || !CBB_finish(&cbb, &txt, &txt_len)) {
|
|
goto err;
|
|
}
|
|
|
|
return (char *)txt;
|
|
|
|
err:
|
|
CBB_cleanup(&cbb);
|
|
return NULL;
|
|
}
|
|
|
|
static int cbs_get_two_digits(CBS *cbs, int *out) {
|
|
uint8_t first_digit, second_digit;
|
|
if (!CBS_get_u8(cbs, &first_digit)) {
|
|
return 0;
|
|
}
|
|
if (!OPENSSL_isdigit(first_digit)) {
|
|
return 0;
|
|
}
|
|
if (!CBS_get_u8(cbs, &second_digit)) {
|
|
return 0;
|
|
}
|
|
if (!OPENSSL_isdigit(second_digit)) {
|
|
return 0;
|
|
}
|
|
*out = (first_digit - '0') * 10 + (second_digit - '0');
|
|
return 1;
|
|
}
|
|
|
|
static int is_valid_day(int year, int month, int day) {
|
|
if (day < 1) {
|
|
return 0;
|
|
}
|
|
switch (month) {
|
|
case 1:
|
|
case 3:
|
|
case 5:
|
|
case 7:
|
|
case 8:
|
|
case 10:
|
|
case 12:
|
|
return day <= 31;
|
|
case 4:
|
|
case 6:
|
|
case 9:
|
|
case 11:
|
|
return day <= 30;
|
|
case 2:
|
|
if ((year % 4 == 0 && year % 100 != 0) || year % 400 == 0) {
|
|
return day <= 29;
|
|
} else {
|
|
return day <= 28;
|
|
}
|
|
default:
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
static int CBS_parse_rfc5280_time_internal(const CBS *cbs, int is_gentime,
|
|
int allow_timezone_offset,
|
|
struct tm *out_tm) {
|
|
int year, month, day, hour, min, sec, tmp;
|
|
CBS copy = *cbs;
|
|
uint8_t tz;
|
|
|
|
if (is_gentime) {
|
|
if (!cbs_get_two_digits(©, &tmp)) {
|
|
return 0;
|
|
}
|
|
year = tmp * 100;
|
|
if (!cbs_get_two_digits(©, &tmp)) {
|
|
return 0;
|
|
}
|
|
year += tmp;
|
|
} else {
|
|
year = 1900;
|
|
if (!cbs_get_two_digits(©, &tmp)) {
|
|
return 0;
|
|
}
|
|
year += tmp;
|
|
if (year < 1950) {
|
|
year += 100;
|
|
}
|
|
if (year >= 2050) {
|
|
return 0; // A Generalized time must be used.
|
|
}
|
|
}
|
|
if (!cbs_get_two_digits(©, &month) || month < 1 ||
|
|
month > 12 || // Reject invalid months.
|
|
!cbs_get_two_digits(©, &day) ||
|
|
!is_valid_day(year, month, day) || // Reject invalid days.
|
|
!cbs_get_two_digits(©, &hour) ||
|
|
hour > 23 || // Reject invalid hours.
|
|
!cbs_get_two_digits(©, &min) ||
|
|
min > 59 || // Reject invalid minutes.
|
|
!cbs_get_two_digits(©, &sec) || sec > 59 || !CBS_get_u8(©, &tz)) {
|
|
return 0;
|
|
}
|
|
|
|
int offset_sign = 0;
|
|
switch (tz) {
|
|
case 'Z':
|
|
break; // We correctly have 'Z' on the end as per spec.
|
|
case '+':
|
|
offset_sign = 1;
|
|
break; // Should not be allowed per RFC 5280.
|
|
case '-':
|
|
offset_sign = -1;
|
|
break; // Should not be allowed per RFC 5280.
|
|
default:
|
|
return 0; // Reject anything else after the time.
|
|
}
|
|
|
|
// If allow_timezone_offset is non-zero, allow for a four digit timezone
|
|
// offset to be specified even though this is not allowed by RFC 5280. We are
|
|
// permissive of this for UTCTimes due to the unfortunate existence of
|
|
// artisinally rolled long lived certificates that were baked into places that
|
|
// are now difficult to change. These certificates were generated with the
|
|
// 'openssl' command that permissively allowed the creation of certificates
|
|
// with notBefore and notAfter times specified as strings for direct
|
|
// certificate inclusion on the command line. For context see cl/237068815.
|
|
//
|
|
// TODO(bbe): This has been expunged from public web-pki as the ecosystem has
|
|
// managed to encourage CA compliance with standards. We should find a way to
|
|
// get rid of this or make it off by default.
|
|
int offset_seconds = 0;
|
|
if (offset_sign != 0) {
|
|
if (!allow_timezone_offset) {
|
|
return 0;
|
|
}
|
|
int offset_hours, offset_minutes;
|
|
if (!cbs_get_two_digits(©, &offset_hours) ||
|
|
offset_hours > 23 || // Reject invalid hours.
|
|
!cbs_get_two_digits(©, &offset_minutes) ||
|
|
offset_minutes > 59) { // Reject invalid minutes.
|
|
return 0;
|
|
}
|
|
offset_seconds = offset_sign * (offset_hours * 3600 + offset_minutes * 60);
|
|
}
|
|
|
|
if (CBS_len(©) != 0) {
|
|
return 0; // Reject invalid lengths.
|
|
}
|
|
|
|
if (out_tm != NULL) {
|
|
// Fill in the tm fields corresponding to what we validated.
|
|
out_tm->tm_year = year - 1900;
|
|
out_tm->tm_mon = month - 1;
|
|
out_tm->tm_mday = day;
|
|
out_tm->tm_hour = hour;
|
|
out_tm->tm_min = min;
|
|
out_tm->tm_sec = sec;
|
|
if (offset_seconds && !OPENSSL_gmtime_adj(out_tm, 0, offset_seconds)) {
|
|
return 0;
|
|
}
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
int CBS_parse_generalized_time(const CBS *cbs, struct tm *out_tm,
|
|
int allow_timezone_offset) {
|
|
return CBS_parse_rfc5280_time_internal(cbs, 1, allow_timezone_offset, out_tm);
|
|
}
|
|
|
|
int CBS_parse_utc_time(const CBS *cbs, struct tm *out_tm,
|
|
int allow_timezone_offset) {
|
|
return CBS_parse_rfc5280_time_internal(cbs, 0, allow_timezone_offset, out_tm);
|
|
}
|
|
|
|
int CBS_get_optional_asn1_int64(CBS *cbs, int64_t *out, CBS_ASN1_TAG tag,
|
|
int64_t default_value) {
|
|
CBS child;
|
|
int present;
|
|
if (!CBS_get_optional_asn1(cbs, &child, &present, tag)) {
|
|
return 0;
|
|
}
|
|
if (present) {
|
|
if (!CBS_get_asn1_int64(&child, out) || CBS_len(&child) != 0) {
|
|
return 0;
|
|
}
|
|
} else {
|
|
*out = default_value;
|
|
}
|
|
return 1;
|
|
}
|