xref: /openbsd/lib/libcrypto/asn1/x_name.c (revision f0d701e2)

/* $OpenBSD: x_name.c,v 1.44 2024/07/08 14:48:49 beck Exp $ */
/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
 * All rights reserved.
 *
 * This package is an SSL implementation written
 * by Eric Young (eay@cryptsoft.com).
 * The implementation was written so as to conform with Netscapes SSL.
 *
 * This library is free for commercial and non-commercial use as long as
 * the following conditions are aheared to.  The following conditions
 * apply to all code found in this distribution, be it the RC4, RSA,
 * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
 * included with this distribution is covered by the same copyright terms
 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
 *
 * Copyright remains Eric Young's, and as such any Copyright notices in
 * the code are not to be removed.
 * If this package is used in a product, Eric Young should be given attribution
 * as the author of the parts of the library used.
 * This can be in the form of a textual message at program startup or
 * in documentation (online or textual) provided with the package.
 *
 * 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 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 acknowledgement:
 *    "This product includes cryptographic software written by
 *     Eric Young (eay@cryptsoft.com)"
 *    The word 'cryptographic' can be left out if the rouines from the library
 *    being used are not cryptographic related :-).
 * 4. If you include any Windows specific code (or a derivative thereof) from
 *    the apps directory (application code) you must include an acknowledgement:
 *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
 *
 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
 * ANY EXPRESS 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 AUTHOR OR 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.
 *
 * The licence and distribution terms for any publically available version or
 * derivative of this code cannot be changed.  i.e. this code cannot simply be
 * copied and put under another distribution licence
 * [including the GNU Public Licence.]
 */

#include <ctype.h>
#include <stdio.h>
#include <string.h>

#include <openssl/asn1t.h>
#include <openssl/err.h>
#include <openssl/x509.h>

#include "asn1_local.h"
#include "x509_local.h"

typedef STACK_OF(X509_NAME_ENTRY) STACK_OF_X509_NAME_ENTRY;
DECLARE_STACK_OF(STACK_OF_X509_NAME_ENTRY)

static int x509_name_ex_d2i(ASN1_VALUE **val, const unsigned char **in,
    long len, const ASN1_ITEM *it, int tag, int aclass, char opt,
    ASN1_TLC *ctx);

static int x509_name_ex_i2d(ASN1_VALUE **val, unsigned char **out,
    const ASN1_ITEM *it, int tag, int aclass);
static int x509_name_ex_new(ASN1_VALUE **val, const ASN1_ITEM *it);
static void x509_name_ex_free(ASN1_VALUE **val, const ASN1_ITEM *it);

static int x509_name_encode(X509_NAME *a);
static int x509_name_canon(X509_NAME *a);
static int asn1_string_canon(ASN1_STRING *out, ASN1_STRING *in);
static int i2d_name_canon(STACK_OF(STACK_OF_X509_NAME_ENTRY) *intname,
    unsigned char **in);

static int x509_name_ex_print(BIO *out, ASN1_VALUE **pval, int indent,
    const char *fname, const ASN1_PCTX *pctx);

static const ASN1_TEMPLATE X509_NAME_ENTRY_seq_tt[] = {
	{
		.offset = offsetof(X509_NAME_ENTRY, object),
		.field_name = "object",
		.item = &ASN1_OBJECT_it,
	},
	{
		.offset = offsetof(X509_NAME_ENTRY, value),
		.field_name = "value",
		.item = &ASN1_PRINTABLE_it,
	},
};

const ASN1_ITEM X509_NAME_ENTRY_it = {
	.itype = ASN1_ITYPE_SEQUENCE,
	.utype = V_ASN1_SEQUENCE,
	.templates = X509_NAME_ENTRY_seq_tt,
	.tcount = sizeof(X509_NAME_ENTRY_seq_tt) / sizeof(ASN1_TEMPLATE),
	.size = sizeof(X509_NAME_ENTRY),
	.sname = "X509_NAME_ENTRY",
};
LCRYPTO_ALIAS(X509_NAME_ENTRY_it);


X509_NAME_ENTRY *
d2i_X509_NAME_ENTRY(X509_NAME_ENTRY **a, const unsigned char **in, long len)
{
	return (X509_NAME_ENTRY *)ASN1_item_d2i((ASN1_VALUE **)a, in, len,
	    &X509_NAME_ENTRY_it);
}
LCRYPTO_ALIAS(d2i_X509_NAME_ENTRY);

int
i2d_X509_NAME_ENTRY(X509_NAME_ENTRY *a, unsigned char **out)
{
	return ASN1_item_i2d((ASN1_VALUE *)a, out, &X509_NAME_ENTRY_it);
}
LCRYPTO_ALIAS(i2d_X509_NAME_ENTRY);

X509_NAME_ENTRY *
X509_NAME_ENTRY_new(void)
{
	return (X509_NAME_ENTRY *)ASN1_item_new(&X509_NAME_ENTRY_it);
}
LCRYPTO_ALIAS(X509_NAME_ENTRY_new);

void
X509_NAME_ENTRY_free(X509_NAME_ENTRY *a)
{
	ASN1_item_free((ASN1_VALUE *)a, &X509_NAME_ENTRY_it);
}
LCRYPTO_ALIAS(X509_NAME_ENTRY_free);

X509_NAME_ENTRY *
X509_NAME_ENTRY_dup(X509_NAME_ENTRY *x)
{
	return ASN1_item_dup(&X509_NAME_ENTRY_it, x);
}
LCRYPTO_ALIAS(X509_NAME_ENTRY_dup);

/* For the "Name" type we need a SEQUENCE OF { SET OF X509_NAME_ENTRY }
 * so declare two template wrappers for this
 */

static const ASN1_TEMPLATE X509_NAME_ENTRIES_item_tt = {
	.flags = ASN1_TFLG_SET_OF,
	.tag = 0,
	.offset = 0,
	.field_name = "RDNS",
	.item = &X509_NAME_ENTRY_it,
};

static const ASN1_ITEM X509_NAME_ENTRIES_it = {
	.itype = ASN1_ITYPE_PRIMITIVE,
	.utype = -1,
	.templates = &X509_NAME_ENTRIES_item_tt,
	.tcount = 0,
	.funcs = NULL,
	.size = 0,
	.sname = "X509_NAME_ENTRIES",
};

static const ASN1_TEMPLATE X509_NAME_INTERNAL_item_tt = {
	.flags = ASN1_TFLG_SEQUENCE_OF,
	.tag = 0,
	.offset = 0,
	.field_name = "Name",
	.item = &X509_NAME_ENTRIES_it,
};

static const ASN1_ITEM X509_NAME_INTERNAL_it = {
	.itype = ASN1_ITYPE_PRIMITIVE,
	.utype = -1,
	.templates = &X509_NAME_INTERNAL_item_tt,
	.tcount = 0,
	.funcs = NULL,
	.size = 0,
	.sname = "X509_NAME_INTERNAL",
};

/* Normally that's where it would end: we'd have two nested STACK structures
 * representing the ASN1. Unfortunately X509_NAME uses a completely different
 * form and caches encodings so we have to process the internal form and convert
 * to the external form.
 */

const ASN1_EXTERN_FUNCS x509_name_ff = {
	.app_data = NULL,
	.asn1_ex_new = x509_name_ex_new,
	.asn1_ex_free = x509_name_ex_free,
	.asn1_ex_clear = NULL,
	.asn1_ex_d2i = x509_name_ex_d2i,
	.asn1_ex_i2d = x509_name_ex_i2d,
	.asn1_ex_print = x509_name_ex_print,
};

const ASN1_ITEM X509_NAME_it = {
	.itype = ASN1_ITYPE_EXTERN,
	.utype = V_ASN1_SEQUENCE,
	.templates = NULL,
	.tcount = 0,
	.funcs = &x509_name_ff,
	.size = 0,
	.sname = "X509_NAME",
};
LCRYPTO_ALIAS(X509_NAME_it);

X509_NAME *
d2i_X509_NAME(X509_NAME **a, const unsigned char **in, long len)
{
	return (X509_NAME *)ASN1_item_d2i((ASN1_VALUE **)a, in, len,
	    &X509_NAME_it);
}
LCRYPTO_ALIAS(d2i_X509_NAME);

int
i2d_X509_NAME(X509_NAME *a, unsigned char **out)
{
	return ASN1_item_i2d((ASN1_VALUE *)a, out, &X509_NAME_it);
}
LCRYPTO_ALIAS(i2d_X509_NAME);

X509_NAME *
X509_NAME_new(void)
{
	return (X509_NAME *)ASN1_item_new(&X509_NAME_it);
}
LCRYPTO_ALIAS(X509_NAME_new);

void
X509_NAME_free(X509_NAME *a)
{
	ASN1_item_free((ASN1_VALUE *)a, &X509_NAME_it);
}
LCRYPTO_ALIAS(X509_NAME_free);

X509_NAME *
X509_NAME_dup(X509_NAME *x)
{
	return ASN1_item_dup(&X509_NAME_it, x);
}
LCRYPTO_ALIAS(X509_NAME_dup);

static int
x509_name_ex_new(ASN1_VALUE **val, const ASN1_ITEM *it)
{
	X509_NAME *ret = NULL;

	ret = malloc(sizeof(X509_NAME));
	if (!ret)
		goto memerr;
	if ((ret->entries = sk_X509_NAME_ENTRY_new_null()) == NULL)
		goto memerr;
	if ((ret->bytes = BUF_MEM_new()) == NULL)
		goto memerr;
	ret->canon_enc = NULL;
	ret->canon_enclen = 0;
	ret->modified = 1;
	*val = (ASN1_VALUE *)ret;
	return 1;

 memerr:
	ASN1error(ERR_R_MALLOC_FAILURE);
	if (ret) {
		if (ret->entries)
			sk_X509_NAME_ENTRY_free(ret->entries);
		free(ret);
	}
	return 0;
}

static void
x509_name_ex_free(ASN1_VALUE **pval, const ASN1_ITEM *it)
{
	X509_NAME *a;

	if (!pval || !*pval)
		return;
	a = (X509_NAME *)*pval;

	BUF_MEM_free(a->bytes);
	sk_X509_NAME_ENTRY_pop_free(a->entries, X509_NAME_ENTRY_free);
	free(a->canon_enc);
	free(a);
	*pval = NULL;
}

static int
x509_name_ex_d2i(ASN1_VALUE **val, const unsigned char **in, long len,
    const ASN1_ITEM *it, int tag, int aclass, char opt, ASN1_TLC *ctx)
{
	const unsigned char *p = *in, *q;
	union {
		STACK_OF(STACK_OF_X509_NAME_ENTRY) *s;
		ASN1_VALUE *a;
	} intname = {NULL};
	union {
		X509_NAME *x;
		ASN1_VALUE *a;
	} nm = {NULL};
	int i, j, ret;
	STACK_OF(X509_NAME_ENTRY) *entries;
	X509_NAME_ENTRY *entry;
	q = p;

	/* Get internal representation of Name */
	ret = ASN1_item_ex_d2i(&intname.a, &p, len,
	    &X509_NAME_INTERNAL_it, tag, aclass, opt, ctx);

	if (ret <= 0)
		return ret;

	if (*val)
		x509_name_ex_free(val, NULL);
	if (!x509_name_ex_new(&nm.a, NULL))
		goto err;
	/* We've decoded it: now cache encoding */
	if (!BUF_MEM_grow(nm.x->bytes, p - q))
		goto err;
	memcpy(nm.x->bytes->data, q, p - q);

	/* Convert internal representation to X509_NAME structure */
	for (i = 0; i < sk_STACK_OF_X509_NAME_ENTRY_num(intname.s); i++) {
		entries = sk_STACK_OF_X509_NAME_ENTRY_value(intname.s, i);
		for (j = 0; j < sk_X509_NAME_ENTRY_num(entries); j++) {
			entry = sk_X509_NAME_ENTRY_value(entries, j);
			entry->set = i;
			if (!sk_X509_NAME_ENTRY_push(nm.x->entries, entry))
				goto err;
		}
		sk_X509_NAME_ENTRY_free(entries);
	}
	sk_STACK_OF_X509_NAME_ENTRY_free(intname.s);
	ret = x509_name_canon(nm.x);
	if (!ret)
		goto err;
	nm.x->modified = 0;
	*val = nm.a;
	*in = p;
	return ret;

 err:
	if (nm.x != NULL)
		X509_NAME_free(nm.x);
	ASN1error(ERR_R_NESTED_ASN1_ERROR);
	return 0;
}

static int
x509_name_ex_i2d(ASN1_VALUE **val, unsigned char **out, const ASN1_ITEM *it,
    int tag, int aclass)
{
	int ret;
	X509_NAME *a = (X509_NAME *)*val;

	if (a->modified) {
		ret = x509_name_encode(a);
		if (ret < 0)
			return ret;
		ret = x509_name_canon(a);
		if (ret < 0)
			return ret;
	}
	ret = a->bytes->length;
	if (out != NULL) {
		memcpy(*out, a->bytes->data, ret);
		*out += ret;
	}
	return ret;
}

static void
local_sk_X509_NAME_ENTRY_free(STACK_OF(X509_NAME_ENTRY) *ne)
{
	sk_X509_NAME_ENTRY_free(ne);
}

static void
local_sk_X509_NAME_ENTRY_pop_free(STACK_OF(X509_NAME_ENTRY) *ne)
{
	sk_X509_NAME_ENTRY_pop_free(ne, X509_NAME_ENTRY_free);
}

static int
x509_name_encode(X509_NAME *a)
{
	union {
		STACK_OF(STACK_OF_X509_NAME_ENTRY) *s;
		ASN1_VALUE *a;
	} intname = {NULL};
	int len;
	unsigned char *p;
	STACK_OF(X509_NAME_ENTRY) *entries = NULL;
	X509_NAME_ENTRY *entry;
	int i, set = -1;

	intname.s = sk_STACK_OF_X509_NAME_ENTRY_new_null();
	if (!intname.s)
		goto memerr;
	for (i = 0; i < sk_X509_NAME_ENTRY_num(a->entries); i++) {
		entry = sk_X509_NAME_ENTRY_value(a->entries, i);
		if (entry->set != set) {
			entries = sk_X509_NAME_ENTRY_new_null();
			if (!entries)
				goto memerr;
			if (!sk_STACK_OF_X509_NAME_ENTRY_push(intname.s,
			    entries))
				goto memerr;
			set = entry->set;
		}
		if (entries == NULL /* if entry->set is bogusly -1 */ ||
		    !sk_X509_NAME_ENTRY_push(entries, entry))
			goto memerr;
	}
	len = ASN1_item_ex_i2d(&intname.a, NULL,
	    &X509_NAME_INTERNAL_it, -1, -1);
	if (!BUF_MEM_grow(a->bytes, len))
		goto memerr;
	p = (unsigned char *)a->bytes->data;
	ASN1_item_ex_i2d(&intname.a, &p, &X509_NAME_INTERNAL_it,
	    -1, -1);
	sk_STACK_OF_X509_NAME_ENTRY_pop_free(intname.s,
	    local_sk_X509_NAME_ENTRY_free);
	a->modified = 0;
	return len;

 memerr:
	sk_STACK_OF_X509_NAME_ENTRY_pop_free(intname.s,
	    local_sk_X509_NAME_ENTRY_free);
	ASN1error(ERR_R_MALLOC_FAILURE);
	return -1;
}

static int
x509_name_ex_print(BIO *out, ASN1_VALUE **pval, int indent, const char *fname,
    const ASN1_PCTX *pctx)
{
	if (X509_NAME_print_ex(out, (X509_NAME *)*pval, indent,
	    pctx->nm_flags) <= 0)
		return 0;
	return 2;
}

/* This function generates the canonical encoding of the Name structure.
 * In it all strings are converted to UTF8, leading, trailing and
 * multiple spaces collapsed, converted to lower case and the leading
 * SEQUENCE header removed.
 *
 * In future we could also normalize the UTF8 too.
 *
 * By doing this comparison of Name structures can be rapidly
 * performed by just using memcmp() of the canonical encoding.
 * By omitting the leading SEQUENCE name constraints of type
 * dirName can also be checked with a simple memcmp().
 */

static int
x509_name_canon(X509_NAME *a)
{
	unsigned char *p;
	STACK_OF(STACK_OF_X509_NAME_ENTRY) *intname = NULL;
	STACK_OF(X509_NAME_ENTRY) *entries = NULL;
	X509_NAME_ENTRY *entry, *tmpentry = NULL;
	int i, len, set = -1, ret = 0;

	if (a->canon_enc) {
		free(a->canon_enc);
		a->canon_enc = NULL;
	}
	/* Special case: empty X509_NAME => null encoding */
	if (sk_X509_NAME_ENTRY_num(a->entries) == 0) {
		a->canon_enclen = 0;
		return 1;
	}
	intname = sk_STACK_OF_X509_NAME_ENTRY_new_null();
	if (!intname)
		goto err;
	for (i = 0; i < sk_X509_NAME_ENTRY_num(a->entries); i++) {
		entry = sk_X509_NAME_ENTRY_value(a->entries, i);
		if (entry->set != set) {
			entries = sk_X509_NAME_ENTRY_new_null();
			if (!entries)
				goto err;
			if (sk_STACK_OF_X509_NAME_ENTRY_push(intname,
			    entries) == 0) {
				sk_X509_NAME_ENTRY_free(entries);
				goto err;
			}
			set = entry->set;
		}
		tmpentry = X509_NAME_ENTRY_new();
		if (tmpentry == NULL)
			goto err;
		tmpentry->object = OBJ_dup(entry->object);
		if (tmpentry->object == NULL)
			goto err;
		if (!asn1_string_canon(tmpentry->value, entry->value))
			goto err;
		if (entries == NULL /* if entry->set is bogusly -1 */ ||
		    !sk_X509_NAME_ENTRY_push(entries, tmpentry))
			goto err;
		tmpentry = NULL;
	}

	/* Finally generate encoding */
	len = i2d_name_canon(intname, NULL);
	if (len < 0)
		goto err;
	p = malloc(len);
	if (p == NULL)
		goto err;
	a->canon_enc = p;
	a->canon_enclen = len;
	i2d_name_canon(intname, &p);
	ret = 1;

 err:
	if (tmpentry)
		X509_NAME_ENTRY_free(tmpentry);
	if (intname)
		sk_STACK_OF_X509_NAME_ENTRY_pop_free(intname,
		    local_sk_X509_NAME_ENTRY_pop_free);
	return ret;
}

/* Bitmap of all the types of string that will be canonicalized. */

#define ASN1_MASK_CANON	\
	(B_ASN1_UTF8STRING | B_ASN1_BMPSTRING | B_ASN1_UNIVERSALSTRING \
	| B_ASN1_PRINTABLESTRING | B_ASN1_T61STRING | B_ASN1_IA5STRING \
	| B_ASN1_VISIBLESTRING)


static int
asn1_string_canon(ASN1_STRING *out, ASN1_STRING *in)
{
	unsigned char *to, *from;
	int len, i;

	/* If type not in bitmask just copy string across */
	if (!(ASN1_tag2bit(in->type) & ASN1_MASK_CANON)) {
		if (!ASN1_STRING_copy(out, in))
			return 0;
		return 1;
	}

	out->type = V_ASN1_UTF8STRING;
	out->length = ASN1_STRING_to_UTF8(&out->data, in);
	if (out->length == -1)
		return 0;

	to = out->data;
	from = to;

	len = out->length;

	/* Convert string in place to canonical form.
	 * Ultimately we may need to handle a wider range of characters
	 * but for now ignore anything with MSB set and rely on the
	 * isspace() and tolower() functions.
	 */

	/* Ignore leading spaces */
	while ((len > 0) && !(*from & 0x80) && isspace(*from)) {
		from++;
		len--;
	}

	to = from + len - 1;

	/* Ignore trailing spaces */
	while ((len > 0) && !(*to & 0x80) && isspace(*to)) {
		to--;
		len--;
	}

	to = out->data;

	i = 0;
	while (i < len) {
		/* If MSB set just copy across */
		if (*from & 0x80) {
			*to++ = *from++;
			i++;
		}
		/* Collapse multiple spaces */
		else if (isspace(*from)) {
			/* Copy one space across */
			*to++ = ' ';
			/* Ignore subsequent spaces. Note: don't need to
			 * check len here because we know the last
			 * character is a non-space so we can't overflow.
			 */
			do {
				from++;
				i++;
			} while (!(*from & 0x80) && isspace(*from));
		} else {
			*to++ = tolower(*from);
			from++;
			i++;
		}
	}

	out->length = to - out->data;

	return 1;
}

static int
i2d_name_canon(STACK_OF(STACK_OF_X509_NAME_ENTRY) *_intname, unsigned char **in)
{
	int i, len, ltmp;
	ASN1_VALUE *v;
	STACK_OF(ASN1_VALUE) *intname = (STACK_OF(ASN1_VALUE) *)_intname;

	len = 0;
	for (i = 0; i < sk_ASN1_VALUE_num(intname); i++) {
		v = sk_ASN1_VALUE_value(intname, i);
		ltmp = ASN1_item_ex_i2d(&v, in,
		    &X509_NAME_ENTRIES_it, -1, -1);
		if (ltmp < 0)
			return ltmp;
		len += ltmp;
	}
	return len;
}

int
X509_NAME_set(X509_NAME **xn, X509_NAME *name)
{
	if (*xn == name)
		return *xn != NULL;
	if ((name = X509_NAME_dup(name)) == NULL)
		return 0;
	X509_NAME_free(*xn);
	*xn = name;
	return 1;
}
LCRYPTO_ALIAS(X509_NAME_set);

int
X509_NAME_get0_der(X509_NAME *nm, const unsigned char **pder, size_t *pderlen)
{
	/* Make sure encoding is valid. */
	if (i2d_X509_NAME(nm, NULL) <= 0)
		return 0;
	if (pder != NULL)
		*pder = (unsigned char *)nm->bytes->data;
	if (pderlen != NULL)
		*pderlen = nm->bytes->length;
	return 1;
}
LCRYPTO_ALIAS(X509_NAME_get0_der);