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src/lib/libcrypto/x509/x509_alt.c

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/* $OpenBSD: x509_alt.c,v 1.16 2023/08/30 00:49:32 tb Exp $ */
/* 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).
*
*/
#include <stdio.h>
#include <string.h>
#include <openssl/conf.h>
#include <openssl/err.h>
#include <openssl/x509v3.h>
#include "x509_internal.h"
static GENERAL_NAMES *v2i_subject_alt(X509V3_EXT_METHOD *method,
X509V3_CTX *ctx, STACK_OF(CONF_VALUE) *nval);
static GENERAL_NAMES *v2i_issuer_alt(X509V3_EXT_METHOD *method,
X509V3_CTX *ctx, STACK_OF(CONF_VALUE) *nval);
static int copy_email(X509V3_CTX *ctx, GENERAL_NAMES *gens, int move_p);
static int copy_issuer(X509V3_CTX *ctx, GENERAL_NAMES *gens);
static int do_othername(GENERAL_NAME *gen, const char *value, X509V3_CTX *ctx);
static int do_dirname(GENERAL_NAME *gen, const char *value, X509V3_CTX *ctx);
const X509V3_EXT_METHOD v3_alt[] = {
{
.ext_nid = NID_subject_alt_name,
.ext_flags = 0,
.it = &GENERAL_NAMES_it,
.ext_new = NULL,
.ext_free = NULL,
.d2i = NULL,
.i2d = NULL,
.i2s = NULL,
.s2i = NULL,
.i2v = (X509V3_EXT_I2V)i2v_GENERAL_NAMES,
.v2i = (X509V3_EXT_V2I)v2i_subject_alt,
.i2r = NULL,
.r2i = NULL,
.usr_data = NULL,
},
{
.ext_nid = NID_issuer_alt_name,
.ext_flags = 0,
.it = &GENERAL_NAMES_it,
.ext_new = NULL,
.ext_free = NULL,
.d2i = NULL,
.i2d = NULL,
.i2s = NULL,
.s2i = NULL,
.i2v = (X509V3_EXT_I2V)i2v_GENERAL_NAMES,
.v2i = (X509V3_EXT_V2I)v2i_issuer_alt,
.i2r = NULL,
.r2i = NULL,
.usr_data = NULL,
},
{
.ext_nid = NID_certificate_issuer,
.ext_flags = 0,
.it = &GENERAL_NAMES_it,
.ext_new = NULL,
.ext_free = NULL,
.d2i = NULL,
.i2d = NULL,
.i2s = NULL,
.s2i = NULL,
.i2v = (X509V3_EXT_I2V)i2v_GENERAL_NAMES,
.v2i = NULL,
.i2r = NULL,
.r2i = NULL,
.usr_data = NULL,
},
};
STACK_OF(CONF_VALUE) *
i2v_GENERAL_NAMES(X509V3_EXT_METHOD *method, GENERAL_NAMES *gens,
STACK_OF(CONF_VALUE) *ret)
{
STACK_OF(CONF_VALUE) *free_ret = NULL;
GENERAL_NAME *gen;
int i;
if (ret == NULL) {
if ((free_ret = ret = sk_CONF_VALUE_new_null()) == NULL)
return NULL;
}
for (i = 0; i < sk_GENERAL_NAME_num(gens); i++) {
if ((gen = sk_GENERAL_NAME_value(gens, i)) == NULL)
goto err;
if ((ret = i2v_GENERAL_NAME(method, gen, ret)) == NULL)
goto err;
}
return ret;
err:
sk_CONF_VALUE_pop_free(free_ret, X509V3_conf_free);
return NULL;
}
LCRYPTO_ALIAS(i2v_GENERAL_NAMES);
STACK_OF(CONF_VALUE) *
i2v_GENERAL_NAME(X509V3_EXT_METHOD *method, GENERAL_NAME *gen,
STACK_OF(CONF_VALUE) *ret)
{
STACK_OF(CONF_VALUE) *free_ret = NULL;
unsigned char *p;
char oline[256], htmp[5];
int i;
if (ret == NULL) {
if ((free_ret = ret = sk_CONF_VALUE_new_null()) == NULL)
return NULL;
}
switch (gen->type) {
case GEN_OTHERNAME:
if (!X509V3_add_value("othername", "<unsupported>", &ret))
goto err;
break;
case GEN_X400:
if (!X509V3_add_value("X400Name", "<unsupported>", &ret))
goto err;
break;
case GEN_EDIPARTY:
if (!X509V3_add_value("EdiPartyName", "<unsupported>", &ret))
goto err;
break;
case GEN_EMAIL:
if (!X509V3_add_value_uchar("email", gen->d.ia5->data, &ret))
goto err;
break;
case GEN_DNS:
if (!X509V3_add_value_uchar("DNS", gen->d.ia5->data, &ret))
goto err;
break;
case GEN_URI:
if (!X509V3_add_value_uchar("URI", gen->d.ia5->data, &ret))
goto err;
break;
case GEN_DIRNAME:
if (X509_NAME_oneline(gen->d.dirn, oline, 256) == NULL)
goto err;
if (!X509V3_add_value("DirName", oline, &ret))
goto err;
break;
case GEN_IPADD: /* XXX */
p = gen->d.ip->data;
if (gen->d.ip->length == 4)
(void) snprintf(oline, sizeof oline,
"%d.%d.%d.%d", p[0], p[1], p[2], p[3]);
else if (gen->d.ip->length == 16) {
oline[0] = 0;
for (i = 0; i < 8; i++) {
(void) snprintf(htmp, sizeof htmp,
"%X", p[0] << 8 | p[1]);
p += 2;
strlcat(oline, htmp, sizeof(oline));
if (i != 7)
strlcat(oline, ":", sizeof(oline));
}
} else {
if (!X509V3_add_value("IP Address", "<invalid>", &ret))
goto err;
break;
}
if (!X509V3_add_value("IP Address", oline, &ret))
goto err;
break;
case GEN_RID:
if (!i2t_ASN1_OBJECT(oline, 256, gen->d.rid))
goto err;
if (!X509V3_add_value("Registered ID", oline, &ret))
goto err;
break;
}
return ret;
err:
sk_CONF_VALUE_pop_free(free_ret, X509V3_conf_free);
return NULL;
}
LCRYPTO_ALIAS(i2v_GENERAL_NAME);
int
GENERAL_NAME_print(BIO *out, GENERAL_NAME *gen)
{
unsigned char *p;
int i;
switch (gen->type) {
case GEN_OTHERNAME:
BIO_printf(out, "othername:<unsupported>");
break;
case GEN_X400:
BIO_printf(out, "X400Name:<unsupported>");
break;
case GEN_EDIPARTY:
/* Maybe fix this: it is supported now */
BIO_printf(out, "EdiPartyName:<unsupported>");
break;
case GEN_EMAIL:
BIO_printf(out, "email:%.*s", gen->d.ia5->length,
gen->d.ia5->data);
break;
case GEN_DNS:
BIO_printf(out, "DNS:%.*s", gen->d.ia5->length,
gen->d.ia5->data);
break;
case GEN_URI:
BIO_printf(out, "URI:%.*s", gen->d.ia5->length,
gen->d.ia5->data);
break;
case GEN_DIRNAME:
BIO_printf(out, "DirName: ");
X509_NAME_print_ex(out, gen->d.dirn, 0, XN_FLAG_ONELINE);
break;
case GEN_IPADD:
p = gen->d.ip->data;
if (gen->d.ip->length == 4)
BIO_printf(out, "IP Address:%d.%d.%d.%d",
p[0], p[1], p[2], p[3]);
else if (gen->d.ip->length == 16) {
BIO_printf(out, "IP Address");
for (i = 0; i < 8; i++) {
BIO_printf(out, ":%X", p[0] << 8 | p[1]);
p += 2;
}
BIO_puts(out, "\n");
} else {
BIO_printf(out, "IP Address:<invalid>");
break;
}
break;
case GEN_RID:
BIO_printf(out, "Registered ID");
i2a_ASN1_OBJECT(out, gen->d.rid);
break;
}
return 1;
}
LCRYPTO_ALIAS(GENERAL_NAME_print);
static GENERAL_NAMES *
v2i_issuer_alt(X509V3_EXT_METHOD *method, X509V3_CTX *ctx,
STACK_OF(CONF_VALUE) *nval)
{
GENERAL_NAMES *gens = NULL;
CONF_VALUE *cnf;
int i;
if ((gens = sk_GENERAL_NAME_new_null()) == NULL) {
X509V3error(ERR_R_MALLOC_FAILURE);
return NULL;
}
for (i = 0; i < sk_CONF_VALUE_num(nval); i++) {
cnf = sk_CONF_VALUE_value(nval, i);
if (name_cmp(cnf->name, "issuer") == 0 && cnf->value != NULL &&
strcmp(cnf->value, "copy") == 0) {
if (!copy_issuer(ctx, gens))
goto err;
} else {
GENERAL_NAME *gen;
if ((gen = v2i_GENERAL_NAME(method, ctx, cnf)) == NULL)
goto err;
if (sk_GENERAL_NAME_push(gens, gen) == 0) {
GENERAL_NAME_free(gen);
goto err;
}
}
}
return gens;
err:
sk_GENERAL_NAME_pop_free(gens, GENERAL_NAME_free);
return NULL;
}
/* Append subject altname of issuer to issuer alt name of subject */
static int
copy_issuer(X509V3_CTX *ctx, GENERAL_NAMES *gens)
{
GENERAL_NAMES *ialt = NULL;
GENERAL_NAME *gen = NULL;
X509_EXTENSION *ext;
int i;
int ret = 0;
if (ctx && (ctx->flags == CTX_TEST))
return 1;
if (!ctx || !ctx->issuer_cert) {
X509V3error(X509V3_R_NO_ISSUER_DETAILS);
goto err;
}
i = X509_get_ext_by_NID(ctx->issuer_cert, NID_subject_alt_name, -1);
if (i < 0)
return 1;
if (!(ext = X509_get_ext(ctx->issuer_cert, i)) ||
!(ialt = X509V3_EXT_d2i(ext))) {
X509V3error(X509V3_R_ISSUER_DECODE_ERROR);
goto err;
}
for (i = 0; i < sk_GENERAL_NAME_num(ialt); i++) {
GENERAL_NAME *val = sk_GENERAL_NAME_value(ialt, i);
if ((gen = GENERAL_NAME_dup(val)) == NULL)
goto err;
if (!sk_GENERAL_NAME_push(gens, gen)) {
X509V3error(ERR_R_MALLOC_FAILURE);
goto err;
}
gen = NULL;
}
ret = 1;
err:
sk_GENERAL_NAME_pop_free(ialt, GENERAL_NAME_free);
GENERAL_NAME_free(gen);
return ret;
}
static GENERAL_NAMES *
v2i_subject_alt(X509V3_EXT_METHOD *method, X509V3_CTX *ctx,
STACK_OF(CONF_VALUE) *nval)
{
GENERAL_NAMES *gens = NULL;
CONF_VALUE *cnf;
int i;
if (!(gens = sk_GENERAL_NAME_new_null())) {
X509V3error(ERR_R_MALLOC_FAILURE);
return NULL;
}
for (i = 0; i < sk_CONF_VALUE_num(nval); i++) {
cnf = sk_CONF_VALUE_value(nval, i);
if (!name_cmp(cnf->name, "email") && cnf->value &&
!strcmp(cnf->value, "copy")) {
if (!copy_email(ctx, gens, 0))
goto err;
} else if (!name_cmp(cnf->name, "email") && cnf->value &&
!strcmp(cnf->value, "move")) {
if (!copy_email(ctx, gens, 1))
goto err;
} else {
GENERAL_NAME *gen;
if (!(gen = v2i_GENERAL_NAME(method, ctx, cnf)))
goto err;
if (sk_GENERAL_NAME_push(gens, gen) == 0) {
GENERAL_NAME_free(gen);
goto err;
}
}
}
return gens;
err:
sk_GENERAL_NAME_pop_free(gens, GENERAL_NAME_free);
return NULL;
}
/* Copy any email addresses in a certificate or request to
* GENERAL_NAMES
*/
static int
copy_email(X509V3_CTX *ctx, GENERAL_NAMES *gens, int move_p)
{
X509_NAME *nm;
ASN1_IA5STRING *email = NULL;
X509_NAME_ENTRY *ne;
GENERAL_NAME *gen = NULL;
int i;
if (ctx != NULL && ctx->flags == CTX_TEST)
return 1;
if (!ctx || (!ctx->subject_cert && !ctx->subject_req)) {
X509V3error(X509V3_R_NO_SUBJECT_DETAILS);
goto err;
}
/* Find the subject name */
if (ctx->subject_cert)
nm = X509_get_subject_name(ctx->subject_cert);
else
nm = X509_REQ_get_subject_name(ctx->subject_req);
/* Now add any email address(es) to STACK */
i = -1;
while ((i = X509_NAME_get_index_by_NID(nm,
NID_pkcs9_emailAddress, i)) >= 0) {
ne = X509_NAME_get_entry(nm, i);
email = ASN1_STRING_dup(X509_NAME_ENTRY_get_data(ne));
if (move_p) {
X509_NAME_delete_entry(nm, i);
X509_NAME_ENTRY_free(ne);
i--;
}
if (!email || !(gen = GENERAL_NAME_new())) {
X509V3error(ERR_R_MALLOC_FAILURE);
goto err;
}
gen->d.ia5 = email;
email = NULL;
gen->type = GEN_EMAIL;
if (!sk_GENERAL_NAME_push(gens, gen)) {
X509V3error(ERR_R_MALLOC_FAILURE);
goto err;
}
gen = NULL;
}
return 1;
err:
GENERAL_NAME_free(gen);
ASN1_IA5STRING_free(email);
return 0;
}
GENERAL_NAMES *
v2i_GENERAL_NAMES(const X509V3_EXT_METHOD *method, X509V3_CTX *ctx,
STACK_OF(CONF_VALUE) *nval)
{
GENERAL_NAME *gen;
GENERAL_NAMES *gens = NULL;
CONF_VALUE *cnf;
int i;
if (!(gens = sk_GENERAL_NAME_new_null())) {
X509V3error(ERR_R_MALLOC_FAILURE);
return NULL;
}
for (i = 0; i < sk_CONF_VALUE_num(nval); i++) {
cnf = sk_CONF_VALUE_value(nval, i);
if (!(gen = v2i_GENERAL_NAME(method, ctx, cnf)))
goto err;
if (sk_GENERAL_NAME_push(gens, gen) == 0) {
GENERAL_NAME_free(gen);
goto err;
}
}
return gens;
err:
sk_GENERAL_NAME_pop_free(gens, GENERAL_NAME_free);
return NULL;
}
LCRYPTO_ALIAS(v2i_GENERAL_NAMES);
GENERAL_NAME *
v2i_GENERAL_NAME(const X509V3_EXT_METHOD *method, X509V3_CTX *ctx,
CONF_VALUE *cnf)
{
return v2i_GENERAL_NAME_ex(NULL, method, ctx, cnf, 0);
}
LCRYPTO_ALIAS(v2i_GENERAL_NAME);
GENERAL_NAME *
a2i_GENERAL_NAME(GENERAL_NAME *out, const X509V3_EXT_METHOD *method,
X509V3_CTX *ctx, int gen_type, const char *value, int is_nc)
{
char is_string = 0;
GENERAL_NAME *gen = NULL;
if (!value) {
X509V3error(X509V3_R_MISSING_VALUE);
return NULL;
}
if (out)
gen = out;
else {
gen = GENERAL_NAME_new();
if (gen == NULL) {
X509V3error(ERR_R_MALLOC_FAILURE);
return NULL;
}
}
switch (gen_type) {
case GEN_URI:
case GEN_EMAIL:
case GEN_DNS:
is_string = 1;
break;
case GEN_RID:
{
ASN1_OBJECT *obj;
if (!(obj = OBJ_txt2obj(value, 0))) {
X509V3error(X509V3_R_BAD_OBJECT);
ERR_asprintf_error_data("value=%s", value);
goto err;
}
gen->d.rid = obj;
}
break;
case GEN_IPADD:
if (is_nc)
gen->d.ip = a2i_IPADDRESS_NC(value);
else
gen->d.ip = a2i_IPADDRESS(value);
if (gen->d.ip == NULL) {
X509V3error(X509V3_R_BAD_IP_ADDRESS);
ERR_asprintf_error_data("value=%s", value);
goto err;
}
break;
case GEN_DIRNAME:
if (!do_dirname(gen, value, ctx)) {
X509V3error(X509V3_R_DIRNAME_ERROR);
goto err;
}
break;
case GEN_OTHERNAME:
if (!do_othername(gen, value, ctx)) {
X509V3error(X509V3_R_OTHERNAME_ERROR);
goto err;
}
break;
default:
X509V3error(X509V3_R_UNSUPPORTED_TYPE);
goto err;
}
if (is_string) {
if (!(gen->d.ia5 = ASN1_IA5STRING_new()) ||
!ASN1_STRING_set(gen->d.ia5, value, strlen(value))) {
X509V3error(ERR_R_MALLOC_FAILURE);
goto err;
}
}
gen->type = gen_type;
return gen;
err:
if (out == NULL)
GENERAL_NAME_free(gen);
return NULL;
}
LCRYPTO_ALIAS(a2i_GENERAL_NAME);
GENERAL_NAME *
v2i_GENERAL_NAME_ex(GENERAL_NAME *out, const X509V3_EXT_METHOD *method,
X509V3_CTX *ctx, CONF_VALUE *cnf, int is_nc)
{
uint8_t *bytes = NULL;
char *name, *value;
GENERAL_NAME *ret;
size_t len = 0;
int type;
CBS cbs;
name = cnf->name;
value = cnf->value;
if (!value) {
X509V3error(X509V3_R_MISSING_VALUE);
return NULL;
}
if (!name_cmp(name, "email"))
type = GEN_EMAIL;
else if (!name_cmp(name, "URI"))
type = GEN_URI;
else if (!name_cmp(name, "DNS"))
type = GEN_DNS;
else if (!name_cmp(name, "RID"))
type = GEN_RID;
else if (!name_cmp(name, "IP"))
type = GEN_IPADD;
else if (!name_cmp(name, "dirName"))
type = GEN_DIRNAME;
else if (!name_cmp(name, "otherName"))
type = GEN_OTHERNAME;
else {
X509V3error(X509V3_R_UNSUPPORTED_OPTION);
ERR_asprintf_error_data("name=%s", name);
return NULL;
}
ret = a2i_GENERAL_NAME(out, method, ctx, type, value, is_nc);
if (ret == NULL)
return NULL;
/*
* Validate what we have for sanity.
*/
if (is_nc) {
struct x509_constraints_name *constraints_name = NULL;
if (!x509_constraints_validate(ret, &constraints_name, NULL)) {
X509V3error(X509V3_R_BAD_OBJECT);
ERR_asprintf_error_data("name=%s", name);
goto err;
}
x509_constraints_name_free(constraints_name);
return ret;
}
type = x509_constraints_general_to_bytes(ret, &bytes, &len);
CBS_init(&cbs, bytes, len);
switch (type) {
case GEN_DNS:
if (!x509_constraints_valid_sandns(&cbs)) {
X509V3error(X509V3_R_BAD_OBJECT);
ERR_asprintf_error_data("name=%s value='%.*s'", name,
(int)len, bytes);
goto err;
}
break;
case GEN_URI:
if (!x509_constraints_uri_host(bytes, len, NULL)) {
X509V3error(X509V3_R_BAD_OBJECT);
ERR_asprintf_error_data("name=%s value='%.*s'", name,
(int)len, bytes);
goto err;
}
break;
case GEN_EMAIL:
if (!x509_constraints_parse_mailbox(&cbs, NULL)) {
X509V3error(X509V3_R_BAD_OBJECT);
ERR_asprintf_error_data("name=%s value='%.*s'", name,
(int)len, bytes);
goto err;
}
break;
case GEN_IPADD:
if (len != 4 && len != 16) {
X509V3error(X509V3_R_BAD_IP_ADDRESS);
ERR_asprintf_error_data("name=%s len=%zu", name, len);
goto err;
}
break;
default:
break;
}
return ret;
err:
if (out == NULL)
GENERAL_NAME_free(ret);
return NULL;
}
LCRYPTO_ALIAS(v2i_GENERAL_NAME_ex);
static int
do_othername(GENERAL_NAME *gen, const char *value, X509V3_CTX *ctx)
{
char *objtmp = NULL, *p;
int objlen;
if (!(p = strchr(value, ';')))
return 0;
if (!(gen->d.otherName = OTHERNAME_new()))
return 0;
/* Free this up because we will overwrite it.
* no need to free type_id because it is static
*/
ASN1_TYPE_free(gen->d.otherName->value);
if (!(gen->d.otherName->value = ASN1_generate_v3(p + 1, ctx)))
return 0;
objlen = p - value;
objtmp = malloc(objlen + 1);
if (objtmp) {
strlcpy(objtmp, value, objlen + 1);
gen->d.otherName->type_id = OBJ_txt2obj(objtmp, 0);
free(objtmp);
} else
gen->d.otherName->type_id = NULL;
if (!gen->d.otherName->type_id)
return 0;
return 1;
}
static int
do_dirname(GENERAL_NAME *gen, const char *value, X509V3_CTX *ctx)
{
int ret;
STACK_OF(CONF_VALUE) *sk;
X509_NAME *nm;
if (!(nm = X509_NAME_new()))
return 0;
sk = X509V3_get_section(ctx, value);
if (!sk) {
X509V3error(X509V3_R_SECTION_NOT_FOUND);
ERR_asprintf_error_data("section=%s", value);
X509_NAME_free(nm);
return 0;
}
/* FIXME: should allow other character types... */
ret = X509V3_NAME_from_section(nm, sk, MBSTRING_ASC);
if (!ret)
X509_NAME_free(nm);
gen->d.dirn = nm;
X509V3_section_free(ctx, sk);
return ret;
}
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