--- /dev/null
+/* Copyright (c) 2014, Google Inc.
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
+ * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
+ * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
+ * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */
+
+#if !defined(__STDC_FORMAT_MACROS)
+#define __STDC_FORMAT_MACROS
+#endif
+
+#include <openssl/buf.h>
+#include <openssl/mem.h>
+#include <openssl/bytestring.h>
+
+#include <assert.h>
+#include <inttypes.h>
+#include <string.h>
+
+#include "internal.h"
+#include "../internal.h"
+
+
+void CBS_init(CBS *cbs, const uint8_t *data, size_t len) {
+ cbs->data = data;
+ cbs->len = len;
+}
+
+static int cbs_get(CBS *cbs, const uint8_t **p, size_t n) {
+ if (cbs->len < n) {
+ return 0;
+ }
+
+ *p = cbs->data;
+ cbs->data += n;
+ cbs->len -= n;
+ return 1;
+}
+
+int CBS_skip(CBS *cbs, size_t len) {
+ const uint8_t *dummy;
+ return cbs_get(cbs, &dummy, len);
+}
+
+const uint8_t *CBS_data(const CBS *cbs) {
+ return cbs->data;
+}
+
+size_t CBS_len(const CBS *cbs) {
+ return cbs->len;
+}
+
+int CBS_stow(const CBS *cbs, uint8_t **out_ptr, size_t *out_len) {
+ OPENSSL_free(*out_ptr);
+ *out_ptr = NULL;
+ *out_len = 0;
+
+ if (cbs->len == 0) {
+ return 1;
+ }
+ *out_ptr = BUF_memdup(cbs->data, cbs->len);
+ if (*out_ptr == NULL) {
+ return 0;
+ }
+ *out_len = cbs->len;
+ return 1;
+}
+
+int CBS_strdup(const CBS *cbs, char **out_ptr) {
+ if (*out_ptr != NULL) {
+ OPENSSL_free(*out_ptr);
+ }
+ *out_ptr = BUF_strndup((const char*)cbs->data, cbs->len);
+ return (*out_ptr != NULL);
+}
+
+int CBS_contains_zero_byte(const CBS *cbs) {
+ return OPENSSL_memchr(cbs->data, 0, cbs->len) != NULL;
+}
+
+int CBS_mem_equal(const CBS *cbs, const uint8_t *data, size_t len) {
+ if (len != cbs->len) {
+ return 0;
+ }
+ return CRYPTO_memcmp(cbs->data, data, len) == 0;
+}
+
+static int cbs_get_u(CBS *cbs, uint32_t *out, size_t len) {
+ uint32_t result = 0;
+ const uint8_t *data;
+
+ if (!cbs_get(cbs, &data, len)) {
+ return 0;
+ }
+ for (size_t i = 0; i < len; i++) {
+ result <<= 8;
+ result |= data[i];
+ }
+ *out = result;
+ return 1;
+}
+
+int CBS_get_u8(CBS *cbs, uint8_t *out) {
+ const uint8_t *v;
+ if (!cbs_get(cbs, &v, 1)) {
+ return 0;
+ }
+ *out = *v;
+ return 1;
+}
+
+int CBS_get_u16(CBS *cbs, uint16_t *out) {
+ uint32_t v;
+ if (!cbs_get_u(cbs, &v, 2)) {
+ return 0;
+ }
+ *out = v;
+ return 1;
+}
+
+int CBS_get_u24(CBS *cbs, uint32_t *out) {
+ return cbs_get_u(cbs, out, 3);
+}
+
+int CBS_get_u32(CBS *cbs, uint32_t *out) {
+ return cbs_get_u(cbs, out, 4);
+}
+
+int CBS_get_last_u8(CBS *cbs, uint8_t *out) {
+ if (cbs->len == 0) {
+ return 0;
+ }
+ *out = cbs->data[cbs->len - 1];
+ cbs->len--;
+ return 1;
+}
+
+int CBS_get_bytes(CBS *cbs, CBS *out, size_t len) {
+ const uint8_t *v;
+ if (!cbs_get(cbs, &v, len)) {
+ return 0;
+ }
+ CBS_init(out, v, len);
+ return 1;
+}
+
+int CBS_copy_bytes(CBS *cbs, uint8_t *out, size_t len) {
+ const uint8_t *v;
+ if (!cbs_get(cbs, &v, len)) {
+ return 0;
+ }
+ OPENSSL_memcpy(out, v, len);
+ return 1;
+}
+
+static int cbs_get_length_prefixed(CBS *cbs, CBS *out, size_t len_len) {
+ uint32_t len;
+ if (!cbs_get_u(cbs, &len, len_len)) {
+ return 0;
+ }
+ return CBS_get_bytes(cbs, out, len);
+}
+
+int CBS_get_u8_length_prefixed(CBS *cbs, CBS *out) {
+ return cbs_get_length_prefixed(cbs, out, 1);
+}
+
+int CBS_get_u16_length_prefixed(CBS *cbs, CBS *out) {
+ return cbs_get_length_prefixed(cbs, out, 2);
+}
+
+int CBS_get_u24_length_prefixed(CBS *cbs, CBS *out) {
+ return cbs_get_length_prefixed(cbs, out, 3);
+}
+
+// parse_base128_integer reads a big-endian base-128 integer from |cbs| and sets
+// |*out| to the result. This is the encoding used in DER for both high tag
+// number form and OID components.
+static int parse_base128_integer(CBS *cbs, uint64_t *out) {
+ uint64_t v = 0;
+ uint8_t b;
+ do {
+ if (!CBS_get_u8(cbs, &b)) {
+ return 0;
+ }
+ if ((v >> (64 - 7)) != 0) {
+ // The value is too large.
+ return 0;
+ }
+ if (v == 0 && b == 0x80) {
+ // The value must be minimally encoded.
+ return 0;
+ }
+ v = (v << 7) | (b & 0x7f);
+
+ // Values end at an octet with the high bit cleared.
+ } while (b & 0x80);
+
+ *out = v;
+ return 1;
+}
+
+static int parse_asn1_tag(CBS *cbs, unsigned *out) {
+ uint8_t tag_byte;
+ if (!CBS_get_u8(cbs, &tag_byte)) {
+ return 0;
+ }
+
+ // ITU-T X.690 section 8.1.2.3 specifies the format for identifiers with a tag
+ // number no greater than 30.
+ //
+ // If the number portion is 31 (0x1f, the largest value that fits in the
+ // allotted bits), then the tag is more than one byte long and the
+ // continuation bytes contain the tag number. This parser only supports tag
+ // numbers less than 31 (and thus single-byte tags).
+ unsigned tag = ((unsigned)tag_byte & 0xe0) << CBS_ASN1_TAG_SHIFT;
+ unsigned tag_number = tag_byte & 0x1f;
+ if (tag_number == 0x1f) {
+ uint64_t v;
+ if (!parse_base128_integer(cbs, &v) ||
+ // Check the tag number is within our supported bounds.
+ v > CBS_ASN1_TAG_NUMBER_MASK ||
+ // Small tag numbers should have used low tag number form.
+ v < 0x1f) {
+ return 0;
+ }
+ tag_number = (unsigned)v;
+ }
+
+ tag |= tag_number;
+
+ *out = tag;
+ return 1;
+}
+
+static int cbs_get_any_asn1_element(CBS *cbs, CBS *out, unsigned *out_tag,
+ size_t *out_header_len, int ber_ok) {
+ CBS header = *cbs;
+ CBS throwaway;
+
+ if (out == NULL) {
+ out = &throwaway;
+ }
+
+ unsigned tag;
+ if (!parse_asn1_tag(&header, &tag)) {
+ return 0;
+ }
+ if (out_tag != NULL) {
+ *out_tag = tag;
+ }
+
+ uint8_t length_byte;
+ if (!CBS_get_u8(&header, &length_byte)) {
+ return 0;
+ }
+
+ size_t header_len = CBS_len(cbs) - CBS_len(&header);
+
+ size_t len;
+ // The format for the length encoding is specified in ITU-T X.690 section
+ // 8.1.3.
+ if ((length_byte & 0x80) == 0) {
+ // Short form length.
+ len = ((size_t) length_byte) + header_len;
+ if (out_header_len != NULL) {
+ *out_header_len = header_len;
+ }
+ } else {
+ // The high bit indicate that this is the long form, while the next 7 bits
+ // encode the number of subsequent octets used to encode the length (ITU-T
+ // X.690 clause 8.1.3.5.b).
+ const size_t num_bytes = length_byte & 0x7f;
+ uint32_t len32;
+
+ if (ber_ok && (tag & CBS_ASN1_CONSTRUCTED) != 0 && num_bytes == 0) {
+ // indefinite length
+ if (out_header_len != NULL) {
+ *out_header_len = header_len;
+ }
+ return CBS_get_bytes(cbs, out, header_len);
+ }
+
+ // ITU-T X.690 clause 8.1.3.5.c specifies that the value 0xff shall not be
+ // used as the first byte of the length. If this parser encounters that
+ // value, num_bytes will be parsed as 127, which will fail the check below.
+ if (num_bytes == 0 || num_bytes > 4) {
+ return 0;
+ }
+ if (!cbs_get_u(&header, &len32, num_bytes)) {
+ return 0;
+ }
+ // ITU-T X.690 section 10.1 (DER length forms) requires encoding the length
+ // with the minimum number of octets.
+ if (len32 < 128) {
+ // Length should have used short-form encoding.
+ return 0;
+ }
+ if ((len32 >> ((num_bytes-1)*8)) == 0) {
+ // Length should have been at least one byte shorter.
+ return 0;
+ }
+ len = len32;
+ if (len + header_len + num_bytes < len) {
+ // Overflow.
+ return 0;
+ }
+ len += header_len + num_bytes;
+ if (out_header_len != NULL) {
+ *out_header_len = header_len + num_bytes;
+ }
+ }
+
+ return CBS_get_bytes(cbs, out, len);
+}
+
+int CBS_get_any_asn1(CBS *cbs, CBS *out, unsigned *out_tag) {
+ size_t header_len;
+ if (!CBS_get_any_asn1_element(cbs, out, out_tag, &header_len)) {
+ return 0;
+ }
+
+ if (!CBS_skip(out, header_len)) {
+ assert(0);
+ return 0;
+ }
+
+ return 1;
+}
+
+int CBS_get_any_asn1_element(CBS *cbs, CBS *out, unsigned *out_tag,
+ size_t *out_header_len) {
+ return cbs_get_any_asn1_element(cbs, out, out_tag, out_header_len,
+ 0 /* DER only */);
+}
+
+int CBS_get_any_ber_asn1_element(CBS *cbs, CBS *out, unsigned *out_tag,
+ size_t *out_header_len) {
+ return cbs_get_any_asn1_element(cbs, out, out_tag, out_header_len,
+ 1 /* BER allowed */);
+}
+
+static int cbs_get_asn1(CBS *cbs, CBS *out, unsigned tag_value,
+ int skip_header) {
+ size_t header_len;
+ unsigned tag;
+ CBS throwaway;
+
+ if (out == NULL) {
+ out = &throwaway;
+ }
+
+ if (!CBS_get_any_asn1_element(cbs, out, &tag, &header_len) ||
+ tag != tag_value) {
+ return 0;
+ }
+
+ if (skip_header && !CBS_skip(out, header_len)) {
+ assert(0);
+ return 0;
+ }
+
+ return 1;
+}
+
+int CBS_get_asn1(CBS *cbs, CBS *out, unsigned tag_value) {
+ return cbs_get_asn1(cbs, out, tag_value, 1 /* skip header */);
+}
+
+int CBS_get_asn1_element(CBS *cbs, CBS *out, unsigned tag_value) {
+ return cbs_get_asn1(cbs, out, tag_value, 0 /* include header */);
+}
+
+int CBS_peek_asn1_tag(const CBS *cbs, unsigned tag_value) {
+ if (CBS_len(cbs) < 1) {
+ return 0;
+ }
+
+ CBS copy = *cbs;
+ unsigned actual_tag;
+ return parse_asn1_tag(©, &actual_tag) && tag_value == actual_tag;
+}
+
+int CBS_get_asn1_uint64(CBS *cbs, uint64_t *out) {
+ CBS bytes;
+ if (!CBS_get_asn1(cbs, &bytes, CBS_ASN1_INTEGER)) {
+ return 0;
+ }
+
+ *out = 0;
+ const uint8_t *data = CBS_data(&bytes);
+ size_t len = CBS_len(&bytes);
+
+ if (len == 0) {
+ // An INTEGER is encoded with at least one octet.
+ return 0;
+ }
+
+ if ((data[0] & 0x80) != 0) {
+ // Negative number.
+ return 0;
+ }
+
+ if (data[0] == 0 && len > 1 && (data[1] & 0x80) == 0) {
+ // Extra leading zeros.
+ return 0;
+ }
+
+ for (size_t i = 0; i < len; i++) {
+ if ((*out >> 56) != 0) {
+ // Too large to represent as a uint64_t.
+ return 0;
+ }
+ *out <<= 8;
+ *out |= data[i];
+ }
+
+ 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, unsigned 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,
+ unsigned 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, unsigned 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, unsigned 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;
+}
+
+static int add_decimal(CBB *out, uint64_t v) {
+ char buf[DECIMAL_SIZE(uint64_t) + 1];
+ BIO_snprintf(buf, sizeof(buf), "%" PRIu64, v);
+ return CBB_add_bytes(out, (const uint8_t *)buf, strlen(buf));
+}
+
+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;
+}
git://repos.xcallymotion.com / motion2.git / blobdiff