/
x509v3.c
1676 lines (1435 loc) · 40.5 KB
/
x509v3.c
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/*
* X.509v3 certificate parsing and processing (RFC 3280 profile)
* Copyright (c) 2006-2007, Jouni Malinen <j@w1.fi>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* Alternatively, this software may be distributed under the terms of BSD
* license.
*
* See README and COPYING for more details.
*/
#include "includes.h"
#include "common.h"
#ifdef CONFIG_INTERNAL_X509
#include "asn1.h"
#include "crypto.h"
#include "x509v3.h"
static void x509_free_name(struct x509_name *name)
{
os_free(name->cn);
os_free(name->c);
os_free(name->l);
os_free(name->st);
os_free(name->o);
os_free(name->ou);
os_free(name->email);
name->cn = name->c = name->l = name->st = name->o = name->ou = NULL;
name->email = NULL;
}
/**
* x509_certificate_free - Free an X.509 certificate
* @cert: Certificate to be freed
*/
void x509_certificate_free(struct x509_certificate *cert)
{
if (cert == NULL)
return;
if (cert->next) {
wpa_printf(MSG_DEBUG, "X509: x509_certificate_free: cer=%p "
"was still on a list (next=%p)\n",
cert, cert->next);
}
x509_free_name(&cert->issuer);
x509_free_name(&cert->subject);
os_free(cert->public_key);
os_free(cert->sign_value);
os_free(cert);
}
/**
* x509_certificate_free - Free an X.509 certificate chain
* @cert: Pointer to the first certificate in the chain
*/
void x509_certificate_chain_free(struct x509_certificate *cert)
{
struct x509_certificate *next;
while (cert) {
next = cert->next;
cert->next = NULL;
x509_certificate_free(cert);
cert = next;
}
}
static int x509_whitespace(char c)
{
return c == ' ' || c == '\t';
}
static void x509_str_strip_whitespace(char *a)
{
char *ipos, *opos;
int remove_whitespace = 1;
ipos = opos = a;
while (*ipos) {
if (remove_whitespace && x509_whitespace(*ipos))
ipos++;
else {
remove_whitespace = x509_whitespace(*ipos);
*opos++ = *ipos++;
}
}
*opos-- = '\0';
if (opos > a && x509_whitespace(*opos))
*opos = '\0';
}
static int x509_str_compare(const char *a, const char *b)
{
char *aa, *bb;
int ret;
if (!a && b)
return -1;
if (a && !b)
return 1;
if (!a && !b)
return 0;
aa = os_strdup(a);
bb = os_strdup(b);
if (aa == NULL || bb == NULL) {
os_free(aa);
os_free(bb);
return os_strcasecmp(a, b);
}
x509_str_strip_whitespace(aa);
x509_str_strip_whitespace(bb);
ret = os_strcasecmp(aa, bb);
os_free(aa);
os_free(bb);
return ret;
}
/**
* x509_name_compare - Compare X.509 certificate names
* @a: Certificate name
* @b: Certificate name
* Returns: <0, 0, or >0 based on whether a is less than, equal to, or
* greater than b
*/
int x509_name_compare(struct x509_name *a, struct x509_name *b)
{
int res;
if (!a && b)
return -1;
if (a && !b)
return 1;
if (!a && !b)
return 0;
res = x509_str_compare(a->cn, b->cn);
if (res)
return res;
res = x509_str_compare(a->c, b->c);
if (res)
return res;
res = x509_str_compare(a->l, b->l);
if (res)
return res;
res = x509_str_compare(a->st, b->st);
if (res)
return res;
res = x509_str_compare(a->o, b->o);
if (res)
return res;
res = x509_str_compare(a->ou, b->ou);
if (res)
return res;
res = x509_str_compare(a->email, b->email);
if (res)
return res;
return 0;
}
static int x509_parse_algorithm_identifier(
const u8 *buf, size_t len,
struct x509_algorithm_identifier *id, const u8 **next)
{
struct asn1_hdr hdr;
const u8 *pos, *end;
/*
* AlgorithmIdentifier ::= SEQUENCE {
* algorithm OBJECT IDENTIFIER,
* parameters ANY DEFINED BY algorithm OPTIONAL
* }
*/
if (asn1_get_next(buf, len, &hdr) < 0 ||
hdr.class != ASN1_CLASS_UNIVERSAL ||
hdr.tag != ASN1_TAG_SEQUENCE) {
wpa_printf(MSG_DEBUG, "X509: Expected SEQUENCE "
"(AlgorithmIdentifier) - found class %d tag 0x%x",
hdr.class, hdr.tag);
return -1;
}
pos = hdr.payload;
end = pos + hdr.length;
if (end > buf + len)
return -1;
*next = end;
if (asn1_get_oid(pos, end - pos, &id->oid, &pos))
return -1;
/* TODO: optional parameters */
return 0;
}
static int x509_parse_public_key(const u8 *buf, size_t len,
struct x509_certificate *cert,
const u8 **next)
{
struct asn1_hdr hdr;
const u8 *pos, *end;
/*
* SubjectPublicKeyInfo ::= SEQUENCE {
* algorithm AlgorithmIdentifier,
* subjectPublicKey BIT STRING
* }
*/
pos = buf;
end = buf + len;
if (asn1_get_next(pos, end - pos, &hdr) < 0 ||
hdr.class != ASN1_CLASS_UNIVERSAL ||
hdr.tag != ASN1_TAG_SEQUENCE) {
wpa_printf(MSG_DEBUG, "X509: Expected SEQUENCE "
"(SubjectPublicKeyInfo) - found class %d tag 0x%x",
hdr.class, hdr.tag);
return -1;
}
pos = hdr.payload;
if (pos + hdr.length > end)
return -1;
end = pos + hdr.length;
*next = end;
if (x509_parse_algorithm_identifier(pos, end - pos,
&cert->public_key_alg, &pos))
return -1;
if (asn1_get_next(pos, end - pos, &hdr) < 0 ||
hdr.class != ASN1_CLASS_UNIVERSAL ||
hdr.tag != ASN1_TAG_BITSTRING) {
wpa_printf(MSG_DEBUG, "X509: Expected BITSTRING "
"(subjectPublicKey) - found class %d tag 0x%x",
hdr.class, hdr.tag);
return -1;
}
if (hdr.length < 1)
return -1;
pos = hdr.payload;
if (*pos) {
wpa_printf(MSG_DEBUG, "X509: BITSTRING - %d unused bits",
*pos);
/*
* TODO: should this be rejected? X.509 certificates are
* unlikely to use such a construction. Now we would end up
* including the extra bits in the buffer which may also be
* ok.
*/
}
os_free(cert->public_key);
cert->public_key = os_malloc(hdr.length - 1);
if (cert->public_key == NULL) {
wpa_printf(MSG_DEBUG, "X509: Failed to allocate memory for "
"public key");
return -1;
}
os_memcpy(cert->public_key, pos + 1, hdr.length - 1);
cert->public_key_len = hdr.length - 1;
wpa_hexdump(MSG_MSGDUMP, "X509: subjectPublicKey",
cert->public_key, cert->public_key_len);
return 0;
}
static int x509_parse_name(const u8 *buf, size_t len, struct x509_name *name,
const u8 **next)
{
struct asn1_hdr hdr;
const u8 *pos, *end, *set_pos, *set_end, *seq_pos, *seq_end;
struct asn1_oid oid;
char **fieldp;
/*
* Name ::= CHOICE { RDNSequence }
* RDNSequence ::= SEQUENCE OF RelativeDistinguishedName
* RelativeDistinguishedName ::= SET OF AttributeTypeAndValue
* AttributeTypeAndValue ::= SEQUENCE {
* type AttributeType,
* value AttributeValue
* }
* AttributeType ::= OBJECT IDENTIFIER
* AttributeValue ::= ANY DEFINED BY AttributeType
*/
if (asn1_get_next(buf, len, &hdr) < 0 ||
hdr.class != ASN1_CLASS_UNIVERSAL ||
hdr.tag != ASN1_TAG_SEQUENCE) {
wpa_printf(MSG_DEBUG, "X509: Expected SEQUENCE "
"(Name / RDNSequencer) - found class %d tag 0x%x",
hdr.class, hdr.tag);
return -1;
}
pos = hdr.payload;
if (pos + hdr.length > buf + len)
return -1;
end = *next = pos + hdr.length;
while (pos < end) {
if (asn1_get_next(pos, end - pos, &hdr) < 0 ||
hdr.class != ASN1_CLASS_UNIVERSAL ||
hdr.tag != ASN1_TAG_SET) {
wpa_printf(MSG_DEBUG, "X509: Expected SET "
"(RelativeDistinguishedName) - found class "
"%d tag 0x%x", hdr.class, hdr.tag);
x509_free_name(name);
return -1;
}
set_pos = hdr.payload;
pos = set_end = hdr.payload + hdr.length;
if (asn1_get_next(set_pos, set_end - set_pos, &hdr) < 0 ||
hdr.class != ASN1_CLASS_UNIVERSAL ||
hdr.tag != ASN1_TAG_SEQUENCE) {
wpa_printf(MSG_DEBUG, "X509: Expected SEQUENCE "
"(AttributeTypeAndValue) - found class %d "
"tag 0x%x", hdr.class, hdr.tag);
x509_free_name(name);
return -1;
}
seq_pos = hdr.payload;
seq_end = hdr.payload + hdr.length;
if (asn1_get_oid(seq_pos, seq_end - seq_pos, &oid, &seq_pos)) {
x509_free_name(name);
return -1;
}
if (asn1_get_next(seq_pos, seq_end - seq_pos, &hdr) < 0 ||
hdr.class != ASN1_CLASS_UNIVERSAL) {
wpa_printf(MSG_DEBUG, "X509: Failed to parse "
"AttributeValue");
x509_free_name(name);
return -1;
}
/* RFC 3280:
* MUST: country, organization, organizational-unit,
* distinguished name qualifier, state or province name,
* common name, serial number.
* SHOULD: locality, title, surname, given name, initials,
* pseudonym, generation qualifier.
* MUST: domainComponent (RFC 2247).
*/
fieldp = NULL;
if (oid.len == 4 &&
oid.oid[0] == 2 && oid.oid[1] == 5 && oid.oid[2] == 4) {
/* id-at ::= 2.5.4 */
switch (oid.oid[3]) {
case 3:
/* commonName */
fieldp = &name->cn;
break;
case 6:
/* countryName */
fieldp = &name->c;
break;
case 7:
/* localityName */
fieldp = &name->l;
break;
case 8:
/* stateOrProvinceName */
fieldp = &name->st;
break;
case 10:
/* organizationName */
fieldp = &name->o;
break;
case 11:
/* organizationalUnitName */
fieldp = &name->ou;
break;
}
} else if (oid.len == 7 &&
oid.oid[0] == 1 && oid.oid[1] == 2 &&
oid.oid[2] == 840 && oid.oid[3] == 113549 &&
oid.oid[4] == 1 && oid.oid[5] == 9 &&
oid.oid[6] == 1) {
/* 1.2.840.113549.1.9.1 - e-mailAddress */
fieldp = &name->email;
}
if (fieldp == NULL) {
wpa_hexdump(MSG_DEBUG, "X509: Unrecognized OID",
(u8 *) oid.oid,
oid.len * sizeof(oid.oid[0]));
wpa_hexdump_ascii(MSG_MSGDUMP, "X509: Attribute Data",
hdr.payload, hdr.length);
continue;
}
os_free(*fieldp);
*fieldp = os_malloc(hdr.length + 1);
if (*fieldp == NULL) {
x509_free_name(name);
return -1;
}
os_memcpy(*fieldp, hdr.payload, hdr.length);
(*fieldp)[hdr.length] = '\0';
}
return 0;
}
/**
* x509_name_string - Convert an X.509 certificate name into a string
* @name: Name to convert
* @buf: Buffer for the string
* @len: Maximum buffer length
*/
void x509_name_string(struct x509_name *name, char *buf, size_t len)
{
char *pos, *end;
int ret;
if (len == 0)
return;
pos = buf;
end = buf + len;
if (name->c) {
ret = os_snprintf(pos, end - pos, "C=%s, ", name->c);
if (ret < 0 || ret >= end - pos)
goto done;
pos += ret;
}
if (name->st) {
ret = os_snprintf(pos, end - pos, "ST=%s, ", name->st);
if (ret < 0 || ret >= end - pos)
goto done;
pos += ret;
}
if (name->l) {
ret = os_snprintf(pos, end - pos, "L=%s, ", name->l);
if (ret < 0 || ret >= end - pos)
goto done;
pos += ret;
}
if (name->o) {
ret = os_snprintf(pos, end - pos, "O=%s, ", name->o);
if (ret < 0 || ret >= end - pos)
goto done;
pos += ret;
}
if (name->ou) {
ret = os_snprintf(pos, end - pos, "OU=%s, ", name->ou);
if (ret < 0 || ret >= end - pos)
goto done;
pos += ret;
}
if (name->cn) {
ret = os_snprintf(pos, end - pos, "CN=%s, ", name->cn);
if (ret < 0 || ret >= end - pos)
goto done;
pos += ret;
}
if (pos > buf + 1 && pos[-1] == ' ' && pos[-2] == ',') {
*pos-- = '\0';
*pos-- = '\0';
}
if (name->email) {
ret = os_snprintf(pos, end - pos, "/emailAddress=%s",
name->email);
if (ret < 0 || ret >= end - pos)
goto done;
pos += ret;
}
done:
end[-1] = '\0';
}
static int x509_parse_time(const u8 *buf, size_t len, u8 asn1_tag,
os_time_t *val)
{
const char *pos;
int year, month, day, hour, min, sec;
/*
* Time ::= CHOICE {
* utcTime UTCTime,
* generalTime GeneralizedTime
* }
*
* UTCTime: YYMMDDHHMMSSZ
* GeneralizedTime: YYYYMMDDHHMMSSZ
*/
pos = (const char *) buf;
switch (asn1_tag) {
case ASN1_TAG_UTCTIME:
if (len != 13 || buf[12] != 'Z') {
wpa_hexdump_ascii(MSG_DEBUG, "X509: Unrecognized "
"UTCTime format", buf, len);
return -1;
}
if (sscanf(pos, "%02d", &year) != 1) {
wpa_hexdump_ascii(MSG_DEBUG, "X509: Failed to parse "
"UTCTime year", buf, len);
return -1;
}
if (year < 50)
year += 2000;
else
year += 1900;
pos += 2;
break;
case ASN1_TAG_GENERALIZEDTIME:
if (len != 15 || buf[14] != 'Z') {
wpa_hexdump_ascii(MSG_DEBUG, "X509: Unrecognized "
"GeneralizedTime format", buf, len);
return -1;
}
if (sscanf(pos, "%04d", &year) != 1) {
wpa_hexdump_ascii(MSG_DEBUG, "X509: Failed to parse "
"GeneralizedTime year", buf, len);
return -1;
}
pos += 4;
break;
default:
wpa_printf(MSG_DEBUG, "X509: Expected UTCTime or "
"GeneralizedTime - found tag 0x%x", asn1_tag);
return -1;
}
if (sscanf(pos, "%02d", &month) != 1) {
wpa_hexdump_ascii(MSG_DEBUG, "X509: Failed to parse Time "
"(month)", buf, len);
return -1;
}
pos += 2;
if (sscanf(pos, "%02d", &day) != 1) {
wpa_hexdump_ascii(MSG_DEBUG, "X509: Failed to parse Time "
"(day)", buf, len);
return -1;
}
pos += 2;
if (sscanf(pos, "%02d", &hour) != 1) {
wpa_hexdump_ascii(MSG_DEBUG, "X509: Failed to parse Time "
"(hour)", buf, len);
return -1;
}
pos += 2;
if (sscanf(pos, "%02d", &min) != 1) {
wpa_hexdump_ascii(MSG_DEBUG, "X509: Failed to parse Time "
"(min)", buf, len);
return -1;
}
pos += 2;
if (sscanf(pos, "%02d", &sec) != 1) {
wpa_hexdump_ascii(MSG_DEBUG, "X509: Failed to parse Time "
"(sec)", buf, len);
return -1;
}
if (os_mktime(year, month, day, hour, min, sec, val) < 0) {
wpa_hexdump_ascii(MSG_DEBUG, "X509: Failed to convert Time",
buf, len);
if (year < 1970) {
/*
* At least some test certificates have been configured
* to use dates prior to 1970. Set the date to
* beginning of 1970 to handle these case.
*/
wpa_printf(MSG_DEBUG, "X509: Year=%d before epoch - "
"assume epoch as the time", year);
*val = 0;
return 0;
}
return -1;
}
return 0;
}
static int x509_parse_validity(const u8 *buf, size_t len,
struct x509_certificate *cert, const u8 **next)
{
struct asn1_hdr hdr;
const u8 *pos;
size_t plen;
/*
* Validity ::= SEQUENCE {
* notBefore Time,
* notAfter Time
* }
*
* RFC 3280, 4.1.2.5:
* CAs conforming to this profile MUST always encode certificate
* validity dates through the year 2049 as UTCTime; certificate
* validity dates in 2050 or later MUST be encoded as GeneralizedTime.
*/
if (asn1_get_next(buf, len, &hdr) < 0 ||
hdr.class != ASN1_CLASS_UNIVERSAL ||
hdr.tag != ASN1_TAG_SEQUENCE) {
wpa_printf(MSG_DEBUG, "X509: Expected SEQUENCE "
"(Validity) - found class %d tag 0x%x",
hdr.class, hdr.tag);
return -1;
}
pos = hdr.payload;
plen = hdr.length;
if (pos + plen > buf + len)
return -1;
*next = pos + plen;
if (asn1_get_next(pos, plen, &hdr) < 0 ||
hdr.class != ASN1_CLASS_UNIVERSAL ||
x509_parse_time(hdr.payload, hdr.length, hdr.tag,
&cert->not_before) < 0) {
wpa_hexdump_ascii(MSG_DEBUG, "X509: Failed to parse notBefore "
"Time", hdr.payload, hdr.length);
return -1;
}
pos = hdr.payload + hdr.length;
plen = *next - pos;
if (asn1_get_next(pos, plen, &hdr) < 0 ||
hdr.class != ASN1_CLASS_UNIVERSAL ||
x509_parse_time(hdr.payload, hdr.length, hdr.tag,
&cert->not_after) < 0) {
wpa_hexdump_ascii(MSG_DEBUG, "X509: Failed to parse notAfter "
"Time", hdr.payload, hdr.length);
return -1;
}
wpa_printf(MSG_MSGDUMP, "X509: Validity: notBefore: %lu notAfter: %lu",
(unsigned long) cert->not_before,
(unsigned long) cert->not_after);
return 0;
}
static int x509_id_ce_oid(struct asn1_oid *oid)
{
/* id-ce arc from X.509 for standard X.509v3 extensions */
return oid->len >= 4 &&
oid->oid[0] == 2 /* joint-iso-ccitt */ &&
oid->oid[1] == 5 /* ds */ &&
oid->oid[2] == 29 /* id-ce */;
}
static int x509_parse_ext_key_usage(struct x509_certificate *cert,
const u8 *pos, size_t len)
{
struct asn1_hdr hdr;
/*
* KeyUsage ::= BIT STRING {
* digitalSignature (0),
* nonRepudiation (1),
* keyEncipherment (2),
* dataEncipherment (3),
* keyAgreement (4),
* keyCertSign (5),
* cRLSign (6),
* encipherOnly (7),
* decipherOnly (8) }
*/
if (asn1_get_next(pos, len, &hdr) < 0 ||
hdr.class != ASN1_CLASS_UNIVERSAL ||
hdr.tag != ASN1_TAG_BITSTRING ||
hdr.length < 1) {
wpa_printf(MSG_DEBUG, "X509: Expected BIT STRING in "
"KeyUsage; found %d tag 0x%x len %d",
hdr.class, hdr.tag, hdr.length);
return -1;
}
cert->extensions_present |= X509_EXT_KEY_USAGE;
cert->key_usage = asn1_bit_string_to_long(hdr.payload, hdr.length);
wpa_printf(MSG_DEBUG, "X509: KeyUsage 0x%lx", cert->key_usage);
return 0;
}
static int x509_parse_ext_basic_constraints(struct x509_certificate *cert,
const u8 *pos, size_t len)
{
struct asn1_hdr hdr;
unsigned long value;
size_t left;
/*
* BasicConstraints ::= SEQUENCE {
* cA BOOLEAN DEFAULT FALSE,
* pathLenConstraint INTEGER (0..MAX) OPTIONAL }
*/
if (asn1_get_next(pos, len, &hdr) < 0 ||
hdr.class != ASN1_CLASS_UNIVERSAL ||
hdr.tag != ASN1_TAG_SEQUENCE) {
wpa_printf(MSG_DEBUG, "X509: Expected SEQUENCE in "
"BasicConstraints; found %d tag 0x%x",
hdr.class, hdr.tag);
return -1;
}
cert->extensions_present |= X509_EXT_BASIC_CONSTRAINTS;
if (hdr.length == 0)
return 0;
if (asn1_get_next(hdr.payload, hdr.length, &hdr) < 0 ||
hdr.class != ASN1_CLASS_UNIVERSAL) {
wpa_printf(MSG_DEBUG, "X509: Failed to parse "
"BasicConstraints");
return -1;
}
if (hdr.tag == ASN1_TAG_BOOLEAN) {
if (hdr.length != 1) {
wpa_printf(MSG_DEBUG, "X509: Unexpected "
"Boolean length (%u) in BasicConstraints",
hdr.length);
return -1;
}
cert->ca = hdr.payload[0];
if (hdr.payload + hdr.length == pos + len) {
wpa_printf(MSG_DEBUG, "X509: BasicConstraints - cA=%d",
cert->ca);
return 0;
}
if (asn1_get_next(hdr.payload + hdr.length, len - hdr.length,
&hdr) < 0 ||
hdr.class != ASN1_CLASS_UNIVERSAL) {
wpa_printf(MSG_DEBUG, "X509: Failed to parse "
"BasicConstraints");
return -1;
}
}
if (hdr.tag != ASN1_TAG_INTEGER) {
wpa_printf(MSG_DEBUG, "X509: Expected INTEGER in "
"BasicConstraints; found class %d tag 0x%x",
hdr.class, hdr.tag);
return -1;
}
pos = hdr.payload;
left = hdr.length;
value = 0;
while (left) {
value <<= 8;
value |= *pos++;
left--;
}
cert->path_len_constraint = value;
cert->extensions_present |= X509_EXT_PATH_LEN_CONSTRAINT;
wpa_printf(MSG_DEBUG, "X509: BasicConstraints - cA=%d "
"pathLenConstraint=%lu",
cert->ca, cert->path_len_constraint);
return 0;
}
static int x509_parse_extension_data(struct x509_certificate *cert,
struct asn1_oid *oid,
const u8 *pos, size_t len)
{
if (!x509_id_ce_oid(oid))
return 1;
/* TODO: add other extensions required by RFC 3280, Ch 4.2:
* certificate policies (section 4.2.1.5)
* the subject alternative name (section 4.2.1.7)
* name constraints (section 4.2.1.11)
* policy constraints (section 4.2.1.12)
* extended key usage (section 4.2.1.13)
* inhibit any-policy (section 4.2.1.15)
*/
switch (oid->oid[3]) {
case 15: /* id-ce-keyUsage */
return x509_parse_ext_key_usage(cert, pos, len);
case 19: /* id-ce-basicConstraints */
return x509_parse_ext_basic_constraints(cert, pos, len);
default:
return 1;
}
}
static int x509_parse_extension(struct x509_certificate *cert,
const u8 *pos, size_t len, const u8 **next)
{
const u8 *end;
struct asn1_hdr hdr;
struct asn1_oid oid;
int critical_ext = 0, res;
char buf[80];
/*
* Extension ::= SEQUENCE {
* extnID OBJECT IDENTIFIER,
* critical BOOLEAN DEFAULT FALSE,
* extnValue OCTET STRING
* }
*/
if (asn1_get_next(pos, len, &hdr) < 0 ||
hdr.class != ASN1_CLASS_UNIVERSAL ||
hdr.tag != ASN1_TAG_SEQUENCE) {
wpa_printf(MSG_DEBUG, "X509: Unexpected ASN.1 header in "
"Extensions: class %d tag 0x%x; expected SEQUENCE",
hdr.class, hdr.tag);
return -1;
}
pos = hdr.payload;
*next = end = pos + hdr.length;
if (asn1_get_oid(pos, end - pos, &oid, &pos) < 0) {
wpa_printf(MSG_DEBUG, "X509: Unexpected ASN.1 data for "
"Extension (expected OID)");
return -1;
}
if (asn1_get_next(pos, end - pos, &hdr) < 0 ||
hdr.class != ASN1_CLASS_UNIVERSAL ||
(hdr.tag != ASN1_TAG_BOOLEAN &&
hdr.tag != ASN1_TAG_OCTETSTRING)) {
wpa_printf(MSG_DEBUG, "X509: Unexpected ASN.1 header in "
"Extensions: class %d tag 0x%x; expected BOOLEAN "
"or OCTET STRING", hdr.class, hdr.tag);
return -1;
}
if (hdr.tag == ASN1_TAG_BOOLEAN) {
if (hdr.length != 1) {
wpa_printf(MSG_DEBUG, "X509: Unexpected "
"Boolean length (%u)", hdr.length);
return -1;
}
critical_ext = hdr.payload[0];
pos = hdr.payload;
if (asn1_get_next(pos, end - pos, &hdr) < 0 ||
(hdr.class != ASN1_CLASS_UNIVERSAL &&
hdr.class != ASN1_CLASS_PRIVATE) ||
hdr.tag != ASN1_TAG_OCTETSTRING) {
wpa_printf(MSG_DEBUG, "X509: Unexpected ASN.1 header "
"in Extensions: class %d tag 0x%x; "
"expected OCTET STRING",
hdr.class, hdr.tag);
return -1;
}
}
asn1_oid_to_str(&oid, buf, sizeof(buf));
wpa_printf(MSG_DEBUG, "X509: Extension: extnID=%s critical=%d",
buf, critical_ext);
wpa_hexdump(MSG_MSGDUMP, "X509: extnValue", hdr.payload, hdr.length);
res = x509_parse_extension_data(cert, &oid, hdr.payload, hdr.length);
if (res < 0)
return res;
if (res == 1 && critical_ext) {
wpa_printf(MSG_INFO, "X509: Unknown critical extension %s",
buf);
return -1;
}
return 0;
}
static int x509_parse_extensions(struct x509_certificate *cert,
const u8 *pos, size_t len)
{
const u8 *end;
struct asn1_hdr hdr;
/* Extensions ::= SEQUENCE SIZE (1..MAX) OF Extension */
if (asn1_get_next(pos, len, &hdr) < 0 ||
hdr.class != ASN1_CLASS_UNIVERSAL ||
hdr.tag != ASN1_TAG_SEQUENCE) {
wpa_printf(MSG_DEBUG, "X509: Unexpected ASN.1 data "
"for Extensions: class %d tag 0x%x; "
"expected SEQUENCE", hdr.class, hdr.tag);
return -1;
}
pos = hdr.payload;
end = pos + hdr.length;
while (pos < end) {
if (x509_parse_extension(cert, pos, end - pos, &pos)
< 0)
return -1;
}
return 0;
}
static int x509_parse_tbs_certificate(const u8 *buf, size_t len,
struct x509_certificate *cert,
const u8 **next)
{
struct asn1_hdr hdr;
const u8 *pos, *end;
size_t left;
char sbuf[128];
unsigned long value;
/* tbsCertificate TBSCertificate ::= SEQUENCE */
if (asn1_get_next(buf, len, &hdr) < 0 ||
hdr.class != ASN1_CLASS_UNIVERSAL ||
hdr.tag != ASN1_TAG_SEQUENCE) {
wpa_printf(MSG_DEBUG, "X509: tbsCertificate did not start "
"with a valid SEQUENCE - found class %d tag 0x%x",
hdr.class, hdr.tag);
return -1;
}
pos = hdr.payload;
end = *next = pos + hdr.length;
/*
* version [0] EXPLICIT Version DEFAULT v1
* Version ::= INTEGER { v1(0), v2(1), v3(2) }
*/
if (asn1_get_next(pos, end - pos, &hdr) < 0)
return -1;
pos = hdr.payload;
if (hdr.class == ASN1_CLASS_CONTEXT_SPECIFIC) {
if (asn1_get_next(pos, end - pos, &hdr) < 0)
return -1;
if (hdr.class != ASN1_CLASS_UNIVERSAL ||
hdr.tag != ASN1_TAG_INTEGER) {
wpa_printf(MSG_DEBUG, "X509: No INTEGER tag found for "
"version field - found class %d tag 0x%x",
hdr.class, hdr.tag);
return -1;
}
if (hdr.length != 1) {
wpa_printf(MSG_DEBUG, "X509: Unexpected version field "
"length %u (expected 1)", hdr.length);
return -1;