ref: 009439541d2c6e8af2596f8fb1b4df85861fd212
dir: /third_party/boringssl/src/crypto/x509/v3_utl.c/
/*
* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
* project.
*/
/* ====================================================================
* Copyright (c) 1999-2003 The OpenSSL Project. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. All advertising materials mentioning features or use of this
* software must display the following acknowledgment:
* "This product includes software developed by the OpenSSL Project
* for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
*
* 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
* endorse or promote products derived from this software without
* prior written permission. For written permission, please contact
* licensing@OpenSSL.org.
*
* 5. Products derived from this software may not be called "OpenSSL"
* nor may "OpenSSL" appear in their names without prior written
* permission of the OpenSSL Project.
*
* 6. Redistributions of any form whatsoever must retain the following
* acknowledgment:
* "This product includes software developed by the OpenSSL Project
* for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
*
* THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
* EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
* OF THE POSSIBILITY OF SUCH DAMAGE.
* ====================================================================
*
* This product includes cryptographic software written by Eric Young
* (eay@cryptsoft.com). This product includes software written by Tim
* Hudson (tjh@cryptsoft.com).
*
*/
/* X509 v3 extension utilities */
#include <ctype.h>
#include <stdio.h>
#include <string.h>
#include <openssl/bn.h>
#include <openssl/bytestring.h>
#include <openssl/conf.h>
#include <openssl/err.h>
#include <openssl/mem.h>
#include <openssl/obj.h>
#include <openssl/x509.h>
#include "../conf/internal.h"
#include "../internal.h"
#include "internal.h"
static char *strip_spaces(char *name);
static int sk_strcmp(const char *const *a, const char *const *b);
static STACK_OF(OPENSSL_STRING) *get_email(const X509_NAME *name,
const GENERAL_NAMES *gens);
static void str_free(OPENSSL_STRING str);
static int append_ia5(STACK_OF(OPENSSL_STRING) **sk,
const ASN1_IA5STRING *email);
static int ipv4_from_asc(uint8_t v4[4], const char *in);
static int ipv6_from_asc(uint8_t v6[16], const char *in);
static int ipv6_cb(const char *elem, size_t len, void *usr);
static int ipv6_hex(uint8_t *out, const char *in, size_t inlen);
// Add a CONF_VALUE name value pair to stack
static int x509V3_add_len_value(const char *name, const char *value,
size_t value_len, int omit_value,
STACK_OF(CONF_VALUE) **extlist) {
CONF_VALUE *vtmp = NULL;
char *tname = NULL, *tvalue = NULL;
int extlist_was_null = *extlist == NULL;
if (name && !(tname = OPENSSL_strdup(name))) {
goto err;
}
if (!omit_value) {
// |CONF_VALUE| cannot represent strings with NULs.
if (OPENSSL_memchr(value, 0, value_len)) {
OPENSSL_PUT_ERROR(X509V3, X509V3_R_INVALID_VALUE);
goto err;
}
tvalue = OPENSSL_strndup(value, value_len);
if (tvalue == NULL) {
goto err;
}
}
if (!(vtmp = CONF_VALUE_new())) {
goto err;
}
if (!*extlist && !(*extlist = sk_CONF_VALUE_new_null())) {
goto err;
}
vtmp->section = NULL;
vtmp->name = tname;
vtmp->value = tvalue;
if (!sk_CONF_VALUE_push(*extlist, vtmp)) {
goto err;
}
return 1;
err:
if (extlist_was_null) {
sk_CONF_VALUE_free(*extlist);
*extlist = NULL;
}
OPENSSL_free(vtmp);
OPENSSL_free(tname);
OPENSSL_free(tvalue);
return 0;
}
int X509V3_add_value(const char *name, const char *value,
STACK_OF(CONF_VALUE) **extlist) {
return x509V3_add_len_value(name, value, value != NULL ? strlen(value) : 0,
/*omit_value=*/value == NULL, extlist);
}
int x509V3_add_value_asn1_string(const char *name, const ASN1_STRING *value,
STACK_OF(CONF_VALUE) **extlist) {
return x509V3_add_len_value(name, (const char *)value->data, value->length,
/*omit_value=*/0, extlist);
}
// Free function for STACK_OF(CONF_VALUE)
void X509V3_conf_free(CONF_VALUE *conf) {
if (!conf) {
return;
}
OPENSSL_free(conf->name);
OPENSSL_free(conf->value);
OPENSSL_free(conf->section);
OPENSSL_free(conf);
}
int X509V3_add_value_bool(const char *name, int asn1_bool,
STACK_OF(CONF_VALUE) **extlist) {
if (asn1_bool) {
return X509V3_add_value(name, "TRUE", extlist);
}
return X509V3_add_value(name, "FALSE", extlist);
}
static char *bignum_to_string(const BIGNUM *bn) {
char *tmp, *ret;
size_t len;
// Display large numbers in hex and small numbers in decimal. Converting to
// decimal takes quadratic time and is no more useful than hex for large
// numbers.
if (BN_num_bits(bn) < 32) {
return BN_bn2dec(bn);
}
tmp = BN_bn2hex(bn);
if (tmp == NULL) {
return NULL;
}
len = strlen(tmp) + 3;
ret = OPENSSL_malloc(len);
if (ret == NULL) {
OPENSSL_free(tmp);
return NULL;
}
// Prepend "0x", but place it after the "-" if negative.
if (tmp[0] == '-') {
OPENSSL_strlcpy(ret, "-0x", len);
OPENSSL_strlcat(ret, tmp + 1, len);
} else {
OPENSSL_strlcpy(ret, "0x", len);
OPENSSL_strlcat(ret, tmp, len);
}
OPENSSL_free(tmp);
return ret;
}
char *i2s_ASN1_ENUMERATED(const X509V3_EXT_METHOD *method,
const ASN1_ENUMERATED *a) {
BIGNUM *bntmp = NULL;
char *strtmp = NULL;
if (!a) {
return NULL;
}
if (!(bntmp = ASN1_ENUMERATED_to_BN(a, NULL)) ||
!(strtmp = bignum_to_string(bntmp))) {
}
BN_free(bntmp);
return strtmp;
}
char *i2s_ASN1_INTEGER(const X509V3_EXT_METHOD *method, const ASN1_INTEGER *a) {
BIGNUM *bntmp = NULL;
char *strtmp = NULL;
if (!a) {
return NULL;
}
if (!(bntmp = ASN1_INTEGER_to_BN(a, NULL)) ||
!(strtmp = bignum_to_string(bntmp))) {
}
BN_free(bntmp);
return strtmp;
}
ASN1_INTEGER *s2i_ASN1_INTEGER(const X509V3_EXT_METHOD *method,
const char *value) {
BIGNUM *bn = NULL;
ASN1_INTEGER *aint;
int isneg, ishex;
int ret;
if (!value) {
OPENSSL_PUT_ERROR(X509V3, X509V3_R_INVALID_NULL_VALUE);
return 0;
}
bn = BN_new();
if (value[0] == '-') {
value++;
isneg = 1;
} else {
isneg = 0;
}
if (value[0] == '0' && ((value[1] == 'x') || (value[1] == 'X'))) {
value += 2;
ishex = 1;
} else {
ishex = 0;
}
if (ishex) {
ret = BN_hex2bn(&bn, value);
} else {
// Decoding from decimal scales quadratically in the input length. Bound the
// largest decimal input we accept in the config parser. 8,192 decimal
// digits allows values up to 27,213 bits. Ths exceeds the largest RSA, DSA,
// or DH modulus we support, and those are not usefully represented in
// decimal.
if (strlen(value) > 8192) {
BN_free(bn);
OPENSSL_PUT_ERROR(X509V3, X509V3_R_INVALID_NUMBER);
return 0;
}
ret = BN_dec2bn(&bn, value);
}
if (!ret || value[ret]) {
BN_free(bn);
OPENSSL_PUT_ERROR(X509V3, X509V3_R_BN_DEC2BN_ERROR);
return 0;
}
if (isneg && BN_is_zero(bn)) {
isneg = 0;
}
aint = BN_to_ASN1_INTEGER(bn, NULL);
BN_free(bn);
if (!aint) {
OPENSSL_PUT_ERROR(X509V3, X509V3_R_BN_TO_ASN1_INTEGER_ERROR);
return 0;
}
if (isneg) {
aint->type |= V_ASN1_NEG;
}
return aint;
}
int X509V3_add_value_int(const char *name, const ASN1_INTEGER *aint,
STACK_OF(CONF_VALUE) **extlist) {
char *strtmp;
int ret;
if (!aint) {
return 1;
}
if (!(strtmp = i2s_ASN1_INTEGER(NULL, aint))) {
return 0;
}
ret = X509V3_add_value(name, strtmp, extlist);
OPENSSL_free(strtmp);
return ret;
}
int X509V3_bool_from_string(const char *str, ASN1_BOOLEAN *out_bool) {
if (!strcmp(str, "TRUE") || !strcmp(str, "true") || !strcmp(str, "Y") ||
!strcmp(str, "y") || !strcmp(str, "YES") || !strcmp(str, "yes")) {
*out_bool = ASN1_BOOLEAN_TRUE;
return 1;
}
if (!strcmp(str, "FALSE") || !strcmp(str, "false") || !strcmp(str, "N") ||
!strcmp(str, "n") || !strcmp(str, "NO") || !strcmp(str, "no")) {
*out_bool = ASN1_BOOLEAN_FALSE;
return 1;
}
OPENSSL_PUT_ERROR(X509V3, X509V3_R_INVALID_BOOLEAN_STRING);
return 0;
}
int X509V3_get_value_bool(const CONF_VALUE *value, ASN1_BOOLEAN *out_bool) {
const char *btmp = value->value;
if (btmp == NULL) {
OPENSSL_PUT_ERROR(X509V3, X509V3_R_INVALID_BOOLEAN_STRING);
goto err;
}
if (!X509V3_bool_from_string(btmp, out_bool)) {
goto err;
}
return 1;
err:
X509V3_conf_err(value);
return 0;
}
int X509V3_get_value_int(const CONF_VALUE *value, ASN1_INTEGER **aint) {
ASN1_INTEGER *itmp;
if (!(itmp = s2i_ASN1_INTEGER(NULL, value->value))) {
X509V3_conf_err(value);
return 0;
}
ASN1_INTEGER_free(*aint);
*aint = itmp;
return 1;
}
#define HDR_NAME 1
#define HDR_VALUE 2
// #define DEBUG
STACK_OF(CONF_VALUE) *X509V3_parse_list(const char *line) {
char *p, *q, c;
char *ntmp, *vtmp;
STACK_OF(CONF_VALUE) *values = NULL;
char *linebuf;
int state;
// We are going to modify the line so copy it first
linebuf = OPENSSL_strdup(line);
if (linebuf == NULL) {
goto err;
}
state = HDR_NAME;
ntmp = NULL;
// Go through all characters
for (p = linebuf, q = linebuf; (c = *p) && (c != '\r') && (c != '\n'); p++) {
switch (state) {
case HDR_NAME:
if (c == ':') {
state = HDR_VALUE;
*p = 0;
ntmp = strip_spaces(q);
if (!ntmp) {
OPENSSL_PUT_ERROR(X509V3, X509V3_R_INVALID_NULL_NAME);
goto err;
}
q = p + 1;
} else if (c == ',') {
*p = 0;
ntmp = strip_spaces(q);
q = p + 1;
#if 0
printf("%s\n", ntmp);
#endif
if (!ntmp) {
OPENSSL_PUT_ERROR(X509V3, X509V3_R_INVALID_NULL_NAME);
goto err;
}
X509V3_add_value(ntmp, NULL, &values);
}
break;
case HDR_VALUE:
if (c == ',') {
state = HDR_NAME;
*p = 0;
vtmp = strip_spaces(q);
#if 0
printf("%s\n", ntmp);
#endif
if (!vtmp) {
OPENSSL_PUT_ERROR(X509V3, X509V3_R_INVALID_NULL_VALUE);
goto err;
}
X509V3_add_value(ntmp, vtmp, &values);
ntmp = NULL;
q = p + 1;
}
}
}
if (state == HDR_VALUE) {
vtmp = strip_spaces(q);
#if 0
printf("%s=%s\n", ntmp, vtmp);
#endif
if (!vtmp) {
OPENSSL_PUT_ERROR(X509V3, X509V3_R_INVALID_NULL_VALUE);
goto err;
}
X509V3_add_value(ntmp, vtmp, &values);
} else {
ntmp = strip_spaces(q);
#if 0
printf("%s\n", ntmp);
#endif
if (!ntmp) {
OPENSSL_PUT_ERROR(X509V3, X509V3_R_INVALID_NULL_NAME);
goto err;
}
X509V3_add_value(ntmp, NULL, &values);
}
OPENSSL_free(linebuf);
return values;
err:
OPENSSL_free(linebuf);
sk_CONF_VALUE_pop_free(values, X509V3_conf_free);
return NULL;
}
// Delete leading and trailing spaces from a string
static char *strip_spaces(char *name) {
char *p, *q;
// Skip over leading spaces
p = name;
while (*p && OPENSSL_isspace((unsigned char)*p)) {
p++;
}
if (!*p) {
return NULL;
}
q = p + strlen(p) - 1;
while ((q != p) && OPENSSL_isspace((unsigned char)*q)) {
q--;
}
if (p != q) {
q[1] = 0;
}
if (!*p) {
return NULL;
}
return p;
}
// hex string utilities
char *x509v3_bytes_to_hex(const uint8_t *in, size_t len) {
CBB cbb;
if (!CBB_init(&cbb, len * 3 + 1)) {
goto err;
}
for (size_t i = 0; i < len; i++) {
static const char hex[] = "0123456789ABCDEF";
if ((i > 0 && !CBB_add_u8(&cbb, ':')) ||
!CBB_add_u8(&cbb, hex[in[i] >> 4]) ||
!CBB_add_u8(&cbb, hex[in[i] & 0xf])) {
goto err;
}
}
uint8_t *ret;
size_t unused_len;
if (!CBB_add_u8(&cbb, 0) || !CBB_finish(&cbb, &ret, &unused_len)) {
goto err;
}
return (char *)ret;
err:
CBB_cleanup(&cbb);
return NULL;
}
unsigned char *x509v3_hex_to_bytes(const char *str, size_t *len) {
unsigned char *hexbuf, *q;
unsigned char ch, cl, *p;
uint8_t high, low;
if (!str) {
OPENSSL_PUT_ERROR(X509V3, X509V3_R_INVALID_NULL_ARGUMENT);
return NULL;
}
if (!(hexbuf = OPENSSL_malloc(strlen(str) >> 1))) {
goto err;
}
for (p = (unsigned char *)str, q = hexbuf; *p;) {
ch = *p++;
if (ch == ':') {
continue;
}
cl = *p++;
if (!cl) {
OPENSSL_PUT_ERROR(X509V3, X509V3_R_ODD_NUMBER_OF_DIGITS);
OPENSSL_free(hexbuf);
return NULL;
}
if (!OPENSSL_fromxdigit(&high, ch)) {
goto badhex;
}
if (!OPENSSL_fromxdigit(&low, cl)) {
goto badhex;
}
*q++ = (high << 4) | low;
}
if (len) {
*len = q - hexbuf;
}
return hexbuf;
err:
OPENSSL_free(hexbuf);
return NULL;
badhex:
OPENSSL_free(hexbuf);
OPENSSL_PUT_ERROR(X509V3, X509V3_R_ILLEGAL_HEX_DIGIT);
return NULL;
}
int x509v3_conf_name_matches(const char *name, const char *cmp) {
// |name| must begin with |cmp|.
size_t len = strlen(cmp);
if (strncmp(name, cmp, len) != 0) {
return 0;
}
// |name| must either be equal to |cmp| or begin with |cmp|, followed by '.'.
return name[len] == '\0' || name[len] == '.';
}
static int sk_strcmp(const char *const *a, const char *const *b) {
return strcmp(*a, *b);
}
STACK_OF(OPENSSL_STRING) *X509_get1_email(const X509 *x) {
GENERAL_NAMES *gens;
STACK_OF(OPENSSL_STRING) *ret;
gens = X509_get_ext_d2i(x, NID_subject_alt_name, NULL, NULL);
ret = get_email(X509_get_subject_name(x), gens);
sk_GENERAL_NAME_pop_free(gens, GENERAL_NAME_free);
return ret;
}
STACK_OF(OPENSSL_STRING) *X509_get1_ocsp(const X509 *x) {
AUTHORITY_INFO_ACCESS *info;
STACK_OF(OPENSSL_STRING) *ret = NULL;
size_t i;
info = X509_get_ext_d2i(x, NID_info_access, NULL, NULL);
if (!info) {
return NULL;
}
for (i = 0; i < sk_ACCESS_DESCRIPTION_num(info); i++) {
ACCESS_DESCRIPTION *ad = sk_ACCESS_DESCRIPTION_value(info, i);
if (OBJ_obj2nid(ad->method) == NID_ad_OCSP) {
if (ad->location->type == GEN_URI) {
if (!append_ia5(&ret, ad->location->d.uniformResourceIdentifier)) {
break;
}
}
}
}
AUTHORITY_INFO_ACCESS_free(info);
return ret;
}
STACK_OF(OPENSSL_STRING) *X509_REQ_get1_email(const X509_REQ *x) {
GENERAL_NAMES *gens;
STACK_OF(X509_EXTENSION) *exts;
STACK_OF(OPENSSL_STRING) *ret;
exts = X509_REQ_get_extensions(x);
gens = X509V3_get_d2i(exts, NID_subject_alt_name, NULL, NULL);
ret = get_email(X509_REQ_get_subject_name(x), gens);
sk_GENERAL_NAME_pop_free(gens, GENERAL_NAME_free);
sk_X509_EXTENSION_pop_free(exts, X509_EXTENSION_free);
return ret;
}
static STACK_OF(OPENSSL_STRING) *get_email(const X509_NAME *name,
const GENERAL_NAMES *gens) {
STACK_OF(OPENSSL_STRING) *ret = NULL;
// Now add any email address(es) to STACK
int i = -1;
// First supplied X509_NAME
while ((i = X509_NAME_get_index_by_NID(name, NID_pkcs9_emailAddress, i)) >=
0) {
const X509_NAME_ENTRY *ne = X509_NAME_get_entry(name, i);
const ASN1_IA5STRING *email = X509_NAME_ENTRY_get_data(ne);
if (!append_ia5(&ret, email)) {
return NULL;
}
}
for (size_t j = 0; j < sk_GENERAL_NAME_num(gens); j++) {
const GENERAL_NAME *gen = sk_GENERAL_NAME_value(gens, j);
if (gen->type != GEN_EMAIL) {
continue;
}
if (!append_ia5(&ret, gen->d.ia5)) {
return NULL;
}
}
return ret;
}
static void str_free(OPENSSL_STRING str) { OPENSSL_free(str); }
static int append_ia5(STACK_OF(OPENSSL_STRING) **sk,
const ASN1_IA5STRING *email) {
// First some sanity checks
if (email->type != V_ASN1_IA5STRING) {
return 1;
}
if (email->data == NULL || email->length == 0) {
return 1;
}
// |OPENSSL_STRING| cannot represent strings with embedded NULs. Do not
// report them as outputs.
if (OPENSSL_memchr(email->data, 0, email->length) != NULL) {
return 1;
}
char *emtmp = NULL;
if (!*sk) {
*sk = sk_OPENSSL_STRING_new(sk_strcmp);
}
if (!*sk) {
goto err;
}
emtmp = OPENSSL_strndup((char *)email->data, email->length);
if (emtmp == NULL) {
goto err;
}
// Don't add duplicates
sk_OPENSSL_STRING_sort(*sk);
if (sk_OPENSSL_STRING_find(*sk, NULL, emtmp)) {
OPENSSL_free(emtmp);
return 1;
}
if (!sk_OPENSSL_STRING_push(*sk, emtmp)) {
goto err;
}
return 1;
err:
// TODO(davidben): Fix the error-handling in this file. It currently relies
// on |append_ia5| leaving |*sk| at NULL on error.
OPENSSL_free(emtmp);
X509_email_free(*sk);
*sk = NULL;
return 0;
}
void X509_email_free(STACK_OF(OPENSSL_STRING) *sk) {
sk_OPENSSL_STRING_pop_free(sk, str_free);
}
typedef int (*equal_fn)(const unsigned char *pattern, size_t pattern_len,
const unsigned char *subject, size_t subject_len,
unsigned int flags);
// Compare while ASCII ignoring case.
static int equal_nocase(const unsigned char *pattern, size_t pattern_len,
const unsigned char *subject, size_t subject_len,
unsigned int flags) {
if (pattern_len != subject_len) {
return 0;
}
while (pattern_len) {
unsigned char l = *pattern;
unsigned char r = *subject;
// The pattern must not contain NUL characters.
if (l == 0) {
return 0;
}
if (l != r) {
if (OPENSSL_tolower(l) != OPENSSL_tolower(r)) {
return 0;
}
}
++pattern;
++subject;
--pattern_len;
}
return 1;
}
// Compare using OPENSSL_memcmp.
static int equal_case(const unsigned char *pattern, size_t pattern_len,
const unsigned char *subject, size_t subject_len,
unsigned int flags) {
if (pattern_len != subject_len) {
return 0;
}
return !OPENSSL_memcmp(pattern, subject, pattern_len);
}
// RFC 5280, section 7.5, requires that only the domain is compared in a
// case-insensitive manner.
static int equal_email(const unsigned char *a, size_t a_len,
const unsigned char *b, size_t b_len,
unsigned int unused_flags) {
size_t i = a_len;
if (a_len != b_len) {
return 0;
}
// We search backwards for the '@' character, so that we do not have to
// deal with quoted local-parts. The domain part is compared in a
// case-insensitive manner.
while (i > 0) {
--i;
if (a[i] == '@' || b[i] == '@') {
if (!equal_nocase(a + i, a_len - i, b + i, a_len - i, 0)) {
return 0;
}
break;
}
}
if (i == 0) {
i = a_len;
}
return equal_case(a, i, b, i, 0);
}
// Compare the prefix and suffix with the subject, and check that the
// characters in-between are valid.
static int wildcard_match(const unsigned char *prefix, size_t prefix_len,
const unsigned char *suffix, size_t suffix_len,
const unsigned char *subject, size_t subject_len,
unsigned int flags) {
const unsigned char *wildcard_start;
const unsigned char *wildcard_end;
const unsigned char *p;
int allow_idna = 0;
if (subject_len < prefix_len + suffix_len) {
return 0;
}
if (!equal_nocase(prefix, prefix_len, subject, prefix_len, flags)) {
return 0;
}
wildcard_start = subject + prefix_len;
wildcard_end = subject + (subject_len - suffix_len);
if (!equal_nocase(wildcard_end, suffix_len, suffix, suffix_len, flags)) {
return 0;
}
// If the wildcard makes up the entire first label, it must match at
// least one character.
if (prefix_len == 0 && *suffix == '.') {
if (wildcard_start == wildcard_end) {
return 0;
}
allow_idna = 1;
}
// IDNA labels cannot match partial wildcards
if (!allow_idna && subject_len >= 4 &&
OPENSSL_strncasecmp((char *)subject, "xn--", 4) == 0) {
return 0;
}
// The wildcard may match a literal '*'
if (wildcard_end == wildcard_start + 1 && *wildcard_start == '*') {
return 1;
}
// Check that the part matched by the wildcard contains only
// permitted characters and only matches a single label.
for (p = wildcard_start; p != wildcard_end; ++p) {
if (!OPENSSL_isalnum(*p) && *p != '-') {
return 0;
}
}
return 1;
}
#define LABEL_START (1 << 0)
#define LABEL_END (1 << 1)
#define LABEL_HYPHEN (1 << 2)
#define LABEL_IDNA (1 << 3)
static const unsigned char *valid_star(const unsigned char *p, size_t len,
unsigned int flags) {
const unsigned char *star = 0;
size_t i;
int state = LABEL_START;
int dots = 0;
for (i = 0; i < len; ++i) {
// Locate first and only legal wildcard, either at the start
// or end of a non-IDNA first and not final label.
if (p[i] == '*') {
int atstart = (state & LABEL_START);
int atend = (i == len - 1 || p[i + 1] == '.');
// At most one wildcard per pattern.
// No wildcards in IDNA labels.
// No wildcards after the first label.
if (star != NULL || (state & LABEL_IDNA) != 0 || dots) {
return NULL;
}
// Only full-label '*.example.com' wildcards.
if (!atstart || !atend) {
return NULL;
}
star = &p[i];
state &= ~LABEL_START;
} else if (OPENSSL_isalnum(p[i])) {
if ((state & LABEL_START) != 0 && len - i >= 4 &&
OPENSSL_strncasecmp((char *)&p[i], "xn--", 4) == 0) {
state |= LABEL_IDNA;
}
state &= ~(LABEL_HYPHEN | LABEL_START);
} else if (p[i] == '.') {
if ((state & (LABEL_HYPHEN | LABEL_START)) != 0) {
return NULL;
}
state = LABEL_START;
++dots;
} else if (p[i] == '-') {
// no domain/subdomain starts with '-'
if ((state & LABEL_START) != 0) {
return NULL;
}
state |= LABEL_HYPHEN;
} else {
return NULL;
}
}
// The final label must not end in a hyphen or ".", and
// there must be at least two dots after the star.
if ((state & (LABEL_START | LABEL_HYPHEN)) != 0 || dots < 2) {
return NULL;
}
return star;
}
// Compare using wildcards.
static int equal_wildcard(const unsigned char *pattern, size_t pattern_len,
const unsigned char *subject, size_t subject_len,
unsigned int flags) {
const unsigned char *star = NULL;
// Subject names starting with '.' can only match a wildcard pattern
// via a subject sub-domain pattern suffix match.
if (!(subject_len > 1 && subject[0] == '.')) {
star = valid_star(pattern, pattern_len, flags);
}
if (star == NULL) {
return equal_nocase(pattern, pattern_len, subject, subject_len, flags);
}
return wildcard_match(pattern, star - pattern, star + 1,
(pattern + pattern_len) - star - 1, subject,
subject_len, flags);
}
int x509v3_looks_like_dns_name(const unsigned char *in, size_t len) {
// This function is used as a heuristic for whether a common name is a
// hostname to be matched, or merely a decorative name to describe the
// subject. This heuristic must be applied to both name constraints and the
// common name fallback, so it must be loose enough to accept hostname
// common names, and tight enough to reject decorative common names.
if (len > 0 && in[len - 1] == '.') {
len--;
}
// Wildcards are allowed in front.
if (len >= 2 && in[0] == '*' && in[1] == '.') {
in += 2;
len -= 2;
}
if (len == 0) {
return 0;
}
size_t label_start = 0;
for (size_t i = 0; i < len; i++) {
unsigned char c = in[i];
if (OPENSSL_isalnum(c) || (c == '-' && i > label_start) ||
// These are not valid characters in hostnames, but commonly found
// in deployments outside the Web PKI.
c == '_' || c == ':') {
continue;
}
// Labels must not be empty.
if (c == '.' && i > label_start && i < len - 1) {
label_start = i + 1;
continue;
}
return 0;
}
return 1;
}
// Compare an ASN1_STRING to a supplied string. If they match return 1. If
// cmp_type > 0 only compare if string matches the type, otherwise convert it
// to UTF8.
static int do_check_string(const ASN1_STRING *a, int cmp_type, equal_fn equal,
unsigned int flags, int check_type, const char *b,
size_t blen, char **peername) {
int rv = 0;
if (!a->data || !a->length) {
return 0;
}
if (cmp_type > 0) {
if (cmp_type != a->type) {
return 0;
}
if (cmp_type == V_ASN1_IA5STRING) {
rv = equal(a->data, a->length, (unsigned char *)b, blen, flags);
} else if (a->length == (int)blen && !OPENSSL_memcmp(a->data, b, blen)) {
rv = 1;
}
if (rv > 0 && peername) {
*peername = OPENSSL_strndup((char *)a->data, a->length);
if (*peername == NULL) {
return -1;
}
}
} else {
int astrlen;
unsigned char *astr;
astrlen = ASN1_STRING_to_UTF8(&astr, a);
if (astrlen < 0) {
return -1;
}
// We check the common name against DNS name constraints if it passes
// |x509v3_looks_like_dns_name|. Thus we must not consider common names
// for DNS fallbacks if they fail this check.
if (check_type == GEN_DNS && !x509v3_looks_like_dns_name(astr, astrlen)) {
rv = 0;
} else {
rv = equal(astr, astrlen, (unsigned char *)b, blen, flags);
}
if (rv > 0 && peername) {
*peername = OPENSSL_strndup((char *)astr, astrlen);
if (*peername == NULL) {
return -1;
}
}
OPENSSL_free(astr);
}
return rv;
}
static int do_x509_check(const X509 *x, const char *chk, size_t chklen,
unsigned int flags, int check_type, char **peername) {
int cnid = NID_undef;
int alt_type;
int rv = 0;
equal_fn equal;
if (check_type == GEN_EMAIL) {
cnid = NID_pkcs9_emailAddress;
alt_type = V_ASN1_IA5STRING;
equal = equal_email;
} else if (check_type == GEN_DNS) {
cnid = NID_commonName;
alt_type = V_ASN1_IA5STRING;
if (flags & X509_CHECK_FLAG_NO_WILDCARDS) {
equal = equal_nocase;
} else {
equal = equal_wildcard;
}
} else {
alt_type = V_ASN1_OCTET_STRING;
equal = equal_case;
}
GENERAL_NAMES *gens = X509_get_ext_d2i(x, NID_subject_alt_name, NULL, NULL);
if (gens) {
for (size_t i = 0; i < sk_GENERAL_NAME_num(gens); i++) {
const GENERAL_NAME *gen = sk_GENERAL_NAME_value(gens, i);
if (gen->type != check_type) {
continue;
}
const ASN1_STRING *cstr;
if (check_type == GEN_EMAIL) {
cstr = gen->d.rfc822Name;
} else if (check_type == GEN_DNS) {
cstr = gen->d.dNSName;
} else {
cstr = gen->d.iPAddress;
}
// Positive on success, negative on error!
if ((rv = do_check_string(cstr, alt_type, equal, flags, check_type, chk,
chklen, peername)) != 0) {
break;
}
}
GENERAL_NAMES_free(gens);
return rv;
}
// We're done if CN-ID is not pertinent
if (cnid == NID_undef || (flags & X509_CHECK_FLAG_NEVER_CHECK_SUBJECT)) {
return 0;
}
int j = -1;
const X509_NAME *name = X509_get_subject_name(x);
while ((j = X509_NAME_get_index_by_NID(name, cnid, j)) >= 0) {
const X509_NAME_ENTRY *ne = X509_NAME_get_entry(name, j);
const ASN1_STRING *str = X509_NAME_ENTRY_get_data(ne);
// Positive on success, negative on error!
if ((rv = do_check_string(str, -1, equal, flags, check_type, chk, chklen,
peername)) != 0) {
return rv;
}
}
return 0;
}
int X509_check_host(const X509 *x, const char *chk, size_t chklen,
unsigned int flags, char **peername) {
if (chk == NULL) {
return -2;
}
if (OPENSSL_memchr(chk, '\0', chklen)) {
return -2;
}
return do_x509_check(x, chk, chklen, flags, GEN_DNS, peername);
}
int X509_check_email(const X509 *x, const char *chk, size_t chklen,
unsigned int flags) {
if (chk == NULL) {
return -2;
}
if (OPENSSL_memchr(chk, '\0', chklen)) {
return -2;
}
return do_x509_check(x, chk, chklen, flags, GEN_EMAIL, NULL);
}
int X509_check_ip(const X509 *x, const unsigned char *chk, size_t chklen,
unsigned int flags) {
if (chk == NULL) {
return -2;
}
return do_x509_check(x, (const char *)chk, chklen, flags, GEN_IPADD, NULL);
}
int X509_check_ip_asc(const X509 *x, const char *ipasc, unsigned int flags) {
unsigned char ipout[16];
size_t iplen;
if (ipasc == NULL) {
return -2;
}
iplen = (size_t)x509v3_a2i_ipadd(ipout, ipasc);
if (iplen == 0) {
return -2;
}
return do_x509_check(x, (const char *)ipout, iplen, flags, GEN_IPADD, NULL);
}
// Convert IP addresses both IPv4 and IPv6 into an OCTET STRING compatible
// with RFC 3280.
ASN1_OCTET_STRING *a2i_IPADDRESS(const char *ipasc) {
unsigned char ipout[16];
ASN1_OCTET_STRING *ret;
int iplen;
iplen = x509v3_a2i_ipadd(ipout, ipasc);
if (!iplen) {
return NULL;
}
ret = ASN1_OCTET_STRING_new();
if (!ret) {
return NULL;
}
if (!ASN1_OCTET_STRING_set(ret, ipout, iplen)) {
ASN1_OCTET_STRING_free(ret);
return NULL;
}
return ret;
}
ASN1_OCTET_STRING *a2i_IPADDRESS_NC(const char *ipasc) {
ASN1_OCTET_STRING *ret = NULL;
unsigned char ipout[32];
char *iptmp = NULL, *p;
int iplen1, iplen2;
p = strchr(ipasc, '/');
if (!p) {
return NULL;
}
iptmp = OPENSSL_strdup(ipasc);
if (!iptmp) {
return NULL;
}
p = iptmp + (p - ipasc);
*p++ = 0;
iplen1 = x509v3_a2i_ipadd(ipout, iptmp);
if (!iplen1) {
goto err;
}
iplen2 = x509v3_a2i_ipadd(ipout + iplen1, p);
OPENSSL_free(iptmp);
iptmp = NULL;
if (!iplen2 || (iplen1 != iplen2)) {
goto err;
}
ret = ASN1_OCTET_STRING_new();
if (!ret) {
goto err;
}
if (!ASN1_OCTET_STRING_set(ret, ipout, iplen1 + iplen2)) {
goto err;
}
return ret;
err:
OPENSSL_free(iptmp);
ASN1_OCTET_STRING_free(ret);
return NULL;
}
int x509v3_a2i_ipadd(uint8_t ipout[16], const char *ipasc) {
// If string contains a ':' assume IPv6
if (strchr(ipasc, ':')) {
if (!ipv6_from_asc(ipout, ipasc)) {
return 0;
}
return 16;
} else {
if (!ipv4_from_asc(ipout, ipasc)) {
return 0;
}
return 4;
}
}
// get_ipv4_component consumes one IPv4 component, terminated by either '.' or
// the end of the string, from |*str|. On success, it returns one, sets |*out|
// to the component, and advances |*str| to the first unconsumed character. On
// invalid input, it returns zero.
static int get_ipv4_component(uint8_t *out_byte, const char **str) {
// Store a slightly larger intermediary so the overflow check is easier.
uint32_t out = 0;
for (;;) {
if (!OPENSSL_isdigit(**str)) {
return 0;
}
out = (out * 10) + (**str - '0');
if (out > 255) {
// Components must be 8-bit.
return 0;
}
(*str)++;
if ((**str) == '.' || (**str) == '\0') {
*out_byte = (uint8_t)out;
return 1;
}
if (out == 0) {
// Reject extra leading zeros. Parsers sometimes treat them as octal, so
// accepting them would misinterpret input.
return 0;
}
}
}
// get_ipv4_dot consumes a '.' from |*str| and advances it. It returns one on
// success and zero if |*str| does not point to a '.'.
static int get_ipv4_dot(const char **str) {
if (**str != '.') {
return 0;
}
(*str)++;
return 1;
}
static int ipv4_from_asc(uint8_t v4[4], const char *in) {
if (!get_ipv4_component(&v4[0], &in) || !get_ipv4_dot(&in) ||
!get_ipv4_component(&v4[1], &in) || !get_ipv4_dot(&in) ||
!get_ipv4_component(&v4[2], &in) || !get_ipv4_dot(&in) ||
!get_ipv4_component(&v4[3], &in) || *in != '\0') {
return 0;
}
return 1;
}
typedef struct {
// Temporary store for IPV6 output
uint8_t tmp[16];
// Total number of bytes in tmp
int total;
// The position of a zero (corresponding to '::')
int zero_pos;
// Number of zeroes
int zero_cnt;
} IPV6_STAT;
static int ipv6_from_asc(uint8_t v6[16], const char *in) {
IPV6_STAT v6stat;
v6stat.total = 0;
v6stat.zero_pos = -1;
v6stat.zero_cnt = 0;
// Treat the IPv6 representation as a list of values separated by ':'.
// The presence of a '::' will parse as one, two or three zero length
// elements.
if (!CONF_parse_list(in, ':', 0, ipv6_cb, &v6stat)) {
return 0;
}
if (v6stat.zero_pos == -1) {
// If no '::' must have exactly 16 bytes
if (v6stat.total != 16) {
return 0;
}
} else {
// If '::' must have less than 16 bytes
if (v6stat.total >= 16) {
return 0;
}
if (v6stat.zero_cnt > 3) {
// More than three zeroes is an error
return 0;
} else if (v6stat.zero_cnt == 3) {
// Can only have three zeroes if nothing else present
if (v6stat.total > 0) {
return 0;
}
} else if (v6stat.zero_cnt == 2) {
// Can only have two zeroes if at start or end
if (v6stat.zero_pos != 0 && v6stat.zero_pos != v6stat.total) {
return 0;
}
} else {
// Can only have one zero if *not* start or end
if (v6stat.zero_pos == 0 || v6stat.zero_pos == v6stat.total) {
return 0;
}
}
}
// Format the result.
if (v6stat.zero_pos >= 0) {
// Copy initial part
OPENSSL_memcpy(v6, v6stat.tmp, v6stat.zero_pos);
// Zero middle
OPENSSL_memset(v6 + v6stat.zero_pos, 0, 16 - v6stat.total);
// Copy final part
if (v6stat.total != v6stat.zero_pos) {
OPENSSL_memcpy(v6 + v6stat.zero_pos + 16 - v6stat.total,
v6stat.tmp + v6stat.zero_pos,
v6stat.total - v6stat.zero_pos);
}
} else {
OPENSSL_memcpy(v6, v6stat.tmp, 16);
}
return 1;
}
static int ipv6_cb(const char *elem, size_t len, void *usr) {
IPV6_STAT *s = usr;
// Error if 16 bytes written
if (s->total == 16) {
return 0;
}
if (len == 0) {
// Zero length element, corresponds to '::'
if (s->zero_pos == -1) {
s->zero_pos = s->total;
} else if (s->zero_pos != s->total) {
// If we've already got a :: its an error
return 0;
}
if (s->zero_cnt >= 3) {
// More than three zeros is an error.
return 0;
}
s->zero_cnt++;
} else {
// If more than 4 characters could be final a.b.c.d form
if (len > 4) {
// Need at least 4 bytes left
if (s->total > 12) {
return 0;
}
// Must be end of string
if (elem[len]) {
return 0;
}
if (!ipv4_from_asc(s->tmp + s->total, elem)) {
return 0;
}
s->total += 4;
} else {
if (!ipv6_hex(s->tmp + s->total, elem, len)) {
return 0;
}
s->total += 2;
}
}
return 1;
}
// Convert a string of up to 4 hex digits into the corresponding IPv6 form.
static int ipv6_hex(uint8_t *out, const char *in, size_t inlen) {
if (inlen > 4) {
return 0;
}
uint16_t num = 0;
while (inlen--) {
uint8_t val;
if (!OPENSSL_fromxdigit(&val, *in++)) {
return 0;
}
num = (num << 4) | val;
}
out[0] = num >> 8;
out[1] = num & 0xff;
return 1;
}
int X509V3_NAME_from_section(X509_NAME *nm, const STACK_OF(CONF_VALUE) *dn_sk,
int chtype) {
if (!nm) {
return 0;
}
for (size_t i = 0; i < sk_CONF_VALUE_num(dn_sk); i++) {
const CONF_VALUE *v = sk_CONF_VALUE_value(dn_sk, i);
const char *type = v->name;
// Skip past any leading X. X: X, etc to allow for multiple instances
for (const char *p = type; *p; p++) {
if ((*p == ':') || (*p == ',') || (*p == '.')) {
p++;
if (*p) {
type = p;
}
break;
}
}
int mval;
if (*type == '+') {
mval = -1;
type++;
} else {
mval = 0;
}
if (!X509_NAME_add_entry_by_txt(nm, type, chtype, (unsigned char *)v->value,
-1, -1, mval)) {
return 0;
}
}
return 1;
}