/src/openssl34/crypto/cms/cms_att.c

Source
/*
 * Copyright 2008-2024 The OpenSSL Project Authors. All Rights Reserved.
 *
 * Licensed under the Apache License 2.0 (the "License").  You may not use
 * this file except in compliance with the License.  You can obtain a copy
 * in the file LICENSE in the source distribution or at
 * https://www.openssl.org/source/license.html
 */

#include <openssl/asn1t.h>
#include <openssl/pem.h>
#include <openssl/x509v3.h>
#include <openssl/err.h>
#include <openssl/cms.h>
#include "internal/nelem.h"
#include "crypto/x509.h"
#include "cms_local.h"

/*-
 * Attribute flags.
 * CMS attribute restrictions are discussed in
 *  - RFC 5652 Section 11.
 * ESS attribute restrictions are discussed in
 *  - RFC 2634 Section 1.3.4  AND
 *  - RFC 5035 Section 5.4
 */
/* This is a signed attribute */
#define CMS_ATTR_F_SIGNED 0x01
/* This is an unsigned attribute */
#define CMS_ATTR_F_UNSIGNED 0x02
/* Must be present if there are any other attributes of the same type */
#define CMS_ATTR_F_REQUIRED_COND 0x10
/* There can only be one instance of this attribute */
#define CMS_ATTR_F_ONLY_ONE 0x20
/* The Attribute's value must have exactly one entry */
#define CMS_ATTR_F_ONE_ATTR_VALUE 0x40

/* Attributes rules for different attributes */
static const struct {
    int nid; /* The attribute id */
    int flags;
} cms_attribute_properties[] = {
    /* See RFC Section 11 */
    { NID_pkcs9_contentType, CMS_ATTR_F_SIGNED | CMS_ATTR_F_ONLY_ONE | CMS_ATTR_F_ONE_ATTR_VALUE | CMS_ATTR_F_REQUIRED_COND },
    { NID_pkcs9_messageDigest, CMS_ATTR_F_SIGNED | CMS_ATTR_F_ONLY_ONE | CMS_ATTR_F_ONE_ATTR_VALUE | CMS_ATTR_F_REQUIRED_COND },
    { NID_pkcs9_signingTime, CMS_ATTR_F_SIGNED | CMS_ATTR_F_ONLY_ONE | CMS_ATTR_F_ONE_ATTR_VALUE },
    { NID_pkcs9_countersignature, CMS_ATTR_F_UNSIGNED },
    /* ESS */
    { NID_id_smime_aa_signingCertificate, CMS_ATTR_F_SIGNED | CMS_ATTR_F_ONLY_ONE | CMS_ATTR_F_ONE_ATTR_VALUE },
    { NID_id_smime_aa_signingCertificateV2, CMS_ATTR_F_SIGNED | CMS_ATTR_F_ONLY_ONE | CMS_ATTR_F_ONE_ATTR_VALUE },
    { NID_id_smime_aa_receiptRequest, CMS_ATTR_F_SIGNED | CMS_ATTR_F_ONLY_ONE | CMS_ATTR_F_ONE_ATTR_VALUE }
};

/* CMS SignedData Attribute utilities */

int CMS_signed_get_attr_count(const CMS_SignerInfo *si)
{
    return X509at_get_attr_count(si->signedAttrs);
}

int CMS_signed_get_attr_by_NID(const CMS_SignerInfo *si, int nid, int lastpos)
{
    return X509at_get_attr_by_NID(si->signedAttrs, nid, lastpos);
}

int CMS_signed_get_attr_by_OBJ(const CMS_SignerInfo *si, const ASN1_OBJECT *obj,
    int lastpos)
{
    return X509at_get_attr_by_OBJ(si->signedAttrs, obj, lastpos);
}

X509_ATTRIBUTE *CMS_signed_get_attr(const CMS_SignerInfo *si, int loc)
{
    return X509at_get_attr(si->signedAttrs, loc);
}

X509_ATTRIBUTE *CMS_signed_delete_attr(CMS_SignerInfo *si, int loc)
{
    return X509at_delete_attr(si->signedAttrs, loc);
}

int CMS_signed_add1_attr(CMS_SignerInfo *si, X509_ATTRIBUTE *attr)
{
    if (ossl_x509at_add1_attr(&si->signedAttrs, attr))
        return 1;
    return 0;
}

int CMS_signed_add1_attr_by_OBJ(CMS_SignerInfo *si,
    const ASN1_OBJECT *obj, int type,
    const void *bytes, int len)
{
    if (ossl_x509at_add1_attr_by_OBJ(&si->signedAttrs, obj, type, bytes, len))
        return 1;
    return 0;
}

int CMS_signed_add1_attr_by_NID(CMS_SignerInfo *si,
    int nid, int type, const void *bytes, int len)
{
    if (ossl_x509at_add1_attr_by_NID(&si->signedAttrs, nid, type, bytes, len))
        return 1;
    return 0;
}

int CMS_signed_add1_attr_by_txt(CMS_SignerInfo *si,
    const char *attrname, int type,
    const void *bytes, int len)
{
    if (ossl_x509at_add1_attr_by_txt(&si->signedAttrs, attrname, type, bytes,
            len))
        return 1;
    return 0;
}

void *CMS_signed_get0_data_by_OBJ(const CMS_SignerInfo *si,
    const ASN1_OBJECT *oid,
    int lastpos, int type)
{
    return X509at_get0_data_by_OBJ(si->signedAttrs, oid, lastpos, type);
}

int CMS_unsigned_get_attr_count(const CMS_SignerInfo *si)
{
    return X509at_get_attr_count(si->unsignedAttrs);
}

int CMS_unsigned_get_attr_by_NID(const CMS_SignerInfo *si, int nid,
    int lastpos)
{
    return X509at_get_attr_by_NID(si->unsignedAttrs, nid, lastpos);
}

int CMS_unsigned_get_attr_by_OBJ(const CMS_SignerInfo *si,
    const ASN1_OBJECT *obj, int lastpos)
{
    return X509at_get_attr_by_OBJ(si->unsignedAttrs, obj, lastpos);
}

X509_ATTRIBUTE *CMS_unsigned_get_attr(const CMS_SignerInfo *si, int loc)
{
    return X509at_get_attr(si->unsignedAttrs, loc);
}

X509_ATTRIBUTE *CMS_unsigned_delete_attr(CMS_SignerInfo *si, int loc)
{
    return X509at_delete_attr(si->unsignedAttrs, loc);
}

int CMS_unsigned_add1_attr(CMS_SignerInfo *si, X509_ATTRIBUTE *attr)
{
    if (ossl_x509at_add1_attr(&si->unsignedAttrs, attr))
        return 1;
    return 0;
}

int CMS_unsigned_add1_attr_by_OBJ(CMS_SignerInfo *si,
    const ASN1_OBJECT *obj, int type,
    const void *bytes, int len)
{
    if (ossl_x509at_add1_attr_by_OBJ(&si->unsignedAttrs, obj, type, bytes, len))
        return 1;
    return 0;
}

int CMS_unsigned_add1_attr_by_NID(CMS_SignerInfo *si,
    int nid, int type,
    const void *bytes, int len)
{
    if (ossl_x509at_add1_attr_by_NID(&si->unsignedAttrs, nid, type, bytes, len))
        return 1;
    return 0;
}

int CMS_unsigned_add1_attr_by_txt(CMS_SignerInfo *si,
    const char *attrname, int type,
    const void *bytes, int len)
{
    if (ossl_x509at_add1_attr_by_txt(&si->unsignedAttrs, attrname,
            type, bytes, len))
        return 1;
    return 0;
}

void *CMS_unsigned_get0_data_by_OBJ(CMS_SignerInfo *si, ASN1_OBJECT *oid,
    int lastpos, int type)
{
    return X509at_get0_data_by_OBJ(si->unsignedAttrs, oid, lastpos, type);
}

/*
 * Retrieve an attribute by nid from a stack of attributes starting at index
 * *lastpos + 1.
 * Returns the attribute or NULL if there is no attribute.
 * If an attribute was found *lastpos returns the index of the found attribute.
 */
static X509_ATTRIBUTE *cms_attrib_get(int nid,
    const STACK_OF(X509_ATTRIBUTE) *attrs,
    int *lastpos)
{
    X509_ATTRIBUTE *at;
    int loc;

    loc = X509at_get_attr_by_NID(attrs, nid, *lastpos);
    if (loc < 0)
        return NULL;

    at = X509at_get_attr(attrs, loc);
    *lastpos = loc;
    return at;
}

static int cms_check_attribute(int nid, int flags, int type,
    const STACK_OF(X509_ATTRIBUTE) *attrs,
    int have_attrs)
{
    int lastpos = -1;
    X509_ATTRIBUTE *at = cms_attrib_get(nid, attrs, &lastpos);

    if (at != NULL) {
        int count = X509_ATTRIBUTE_count(at);

        /* Is this attribute allowed? */
        if (((flags & type) == 0)
            /* check if multiple attributes of the same type are allowed */
            || (((flags & CMS_ATTR_F_ONLY_ONE) != 0)
                && cms_attrib_get(nid, attrs, &lastpos) != NULL)
            /* Check if attribute should have exactly one value in its set */
            || (((flags & CMS_ATTR_F_ONE_ATTR_VALUE) != 0)
                && count != 1)
            /* There should be at least one value */
            || count == 0)
            return 0;
    } else {
        /* fail if a required attribute is missing */
        if (have_attrs
            && ((flags & CMS_ATTR_F_REQUIRED_COND) != 0)
            && (flags & type) != 0)
            return 0;
    }
    return 1;
}

/*
 * Check that the signerinfo attributes obey the attribute rules which includes
 * the following checks
 * - If any signed attributes exist then there must be a Content Type
 * and Message Digest attribute in the signed attributes.
 * - The countersignature attribute is an optional unsigned attribute only.
 * - Content Type, Message Digest, and Signing time attributes are signed
 *     attributes. Only one instance of each is allowed, with each of these
 *     attributes containing a single attribute value in its set.
 */
int ossl_cms_si_check_attributes(const CMS_SignerInfo *si)
{
    int i;
    int have_signed_attrs = (CMS_signed_get_attr_count(si) > 0);
    int have_unsigned_attrs = (CMS_unsigned_get_attr_count(si) > 0);

    for (i = 0; i < (int)OSSL_NELEM(cms_attribute_properties); ++i) {
        int nid = cms_attribute_properties[i].nid;
        int flags = cms_attribute_properties[i].flags;

        if (!cms_check_attribute(nid, flags, CMS_ATTR_F_SIGNED,
                si->signedAttrs, have_signed_attrs)
            || !cms_check_attribute(nid, flags, CMS_ATTR_F_UNSIGNED,
                si->unsignedAttrs, have_unsigned_attrs)) {
            ERR_raise(ERR_LIB_CMS, CMS_R_ATTRIBUTE_ERROR);
            return 0;
        }
    }
    return 1;
}

Coverage Report

Created: 2025-12-31 06:58

Line	Count	Source
1		/*
2		* Copyright 2008-2024 The OpenSSL Project Authors. All Rights Reserved.
3		*
4		* Licensed under the Apache License 2.0 (the "License"). You may not use
5		* this file except in compliance with the License. You can obtain a copy
6		* in the file LICENSE in the source distribution or at
7		* https://www.openssl.org/source/license.html
8		*/
9
10		#include <openssl/asn1t.h>
11		#include <openssl/pem.h>
12		#include <openssl/x509v3.h>
13		#include <openssl/err.h>
14		#include <openssl/cms.h>
15		#include "internal/nelem.h"
16		#include "crypto/x509.h"
17		#include "cms_local.h"
18
19		/*-
20		* Attribute flags.
21		* CMS attribute restrictions are discussed in
22		* - RFC 5652 Section 11.
23		* ESS attribute restrictions are discussed in
24		* - RFC 2634 Section 1.3.4 AND
25		* - RFC 5035 Section 5.4
26		*/
27		/* This is a signed attribute */
28	0	#define CMS_ATTR_F_SIGNED 0x01
29		/* This is an unsigned attribute */
30	0	#define CMS_ATTR_F_UNSIGNED 0x02
31		/* Must be present if there are any other attributes of the same type */
32	0	#define CMS_ATTR_F_REQUIRED_COND 0x10
33		/* There can only be one instance of this attribute */
34	0	#define CMS_ATTR_F_ONLY_ONE 0x20
35		/* The Attribute's value must have exactly one entry */
36	0	#define CMS_ATTR_F_ONE_ATTR_VALUE 0x40
37
38		/* Attributes rules for different attributes */
39		static const struct {
40		int nid; /* The attribute id */
41		int flags;
42		} cms_attribute_properties[] = {
43		/* See RFC Section 11 */
44		{ NID_pkcs9_contentType, CMS_ATTR_F_SIGNED \| CMS_ATTR_F_ONLY_ONE \| CMS_ATTR_F_ONE_ATTR_VALUE \| CMS_ATTR_F_REQUIRED_COND },
45		{ NID_pkcs9_messageDigest, CMS_ATTR_F_SIGNED \| CMS_ATTR_F_ONLY_ONE \| CMS_ATTR_F_ONE_ATTR_VALUE \| CMS_ATTR_F_REQUIRED_COND },
46		{ NID_pkcs9_signingTime, CMS_ATTR_F_SIGNED \| CMS_ATTR_F_ONLY_ONE \| CMS_ATTR_F_ONE_ATTR_VALUE },
47		{ NID_pkcs9_countersignature, CMS_ATTR_F_UNSIGNED },
48		/* ESS */
49		{ NID_id_smime_aa_signingCertificate, CMS_ATTR_F_SIGNED \| CMS_ATTR_F_ONLY_ONE \| CMS_ATTR_F_ONE_ATTR_VALUE },
50		{ NID_id_smime_aa_signingCertificateV2, CMS_ATTR_F_SIGNED \| CMS_ATTR_F_ONLY_ONE \| CMS_ATTR_F_ONE_ATTR_VALUE },
51		{ NID_id_smime_aa_receiptRequest, CMS_ATTR_F_SIGNED \| CMS_ATTR_F_ONLY_ONE \| CMS_ATTR_F_ONE_ATTR_VALUE }
52		};
53
54		/* CMS SignedData Attribute utilities */
55
56		int CMS_signed_get_attr_count(const CMS_SignerInfo *si)
57	0	{
58	0	return X509at_get_attr_count(si->signedAttrs);
59	0	}
60
61		int CMS_signed_get_attr_by_NID(const CMS_SignerInfo *si, int nid, int lastpos)
62	0	{
63	0	return X509at_get_attr_by_NID(si->signedAttrs, nid, lastpos);
64	0	}
65
66		int CMS_signed_get_attr_by_OBJ(const CMS_SignerInfo si, const ASN1_OBJECT obj,
67		int lastpos)
68	0	{
69	0	return X509at_get_attr_by_OBJ(si->signedAttrs, obj, lastpos);
70	0	}
71
72		X509_ATTRIBUTE CMS_signed_get_attr(const CMS_SignerInfo si, int loc)
73	0	{
74	0	return X509at_get_attr(si->signedAttrs, loc);
75	0	}
76
77		X509_ATTRIBUTE CMS_signed_delete_attr(CMS_SignerInfo si, int loc)
78	0	{
79	0	return X509at_delete_attr(si->signedAttrs, loc);
80	0	}
81
82		int CMS_signed_add1_attr(CMS_SignerInfo si, X509_ATTRIBUTE attr)
83	0	{
84	0	if (ossl_x509at_add1_attr(&si->signedAttrs, attr))
85	0	return 1;
86	0	return 0;
87	0	}
88
89		int CMS_signed_add1_attr_by_OBJ(CMS_SignerInfo *si,
90		const ASN1_OBJECT *obj, int type,
91		const void *bytes, int len)
92	0	{
93	0	if (ossl_x509at_add1_attr_by_OBJ(&si->signedAttrs, obj, type, bytes, len))
94	0	return 1;
95	0	return 0;
96	0	}
97
98		int CMS_signed_add1_attr_by_NID(CMS_SignerInfo *si,
99		int nid, int type, const void *bytes, int len)
100	0	{
101	0	if (ossl_x509at_add1_attr_by_NID(&si->signedAttrs, nid, type, bytes, len))
102	0	return 1;
103	0	return 0;
104	0	}
105
106		int CMS_signed_add1_attr_by_txt(CMS_SignerInfo *si,
107		const char *attrname, int type,
108		const void *bytes, int len)
109	0	{
110	0	if (ossl_x509at_add1_attr_by_txt(&si->signedAttrs, attrname, type, bytes,
111	0	len))
112	0	return 1;
113	0	return 0;
114	0	}
115
116		void CMS_signed_get0_data_by_OBJ(const CMS_SignerInfo si,
117		const ASN1_OBJECT *oid,
118		int lastpos, int type)
119	0	{
120	0	return X509at_get0_data_by_OBJ(si->signedAttrs, oid, lastpos, type);
121	0	}
122
123		int CMS_unsigned_get_attr_count(const CMS_SignerInfo *si)
124	0	{
125	0	return X509at_get_attr_count(si->unsignedAttrs);
126	0	}
127
128		int CMS_unsigned_get_attr_by_NID(const CMS_SignerInfo *si, int nid,
129		int lastpos)
130	0	{
131	0	return X509at_get_attr_by_NID(si->unsignedAttrs, nid, lastpos);
132	0	}
133
134		int CMS_unsigned_get_attr_by_OBJ(const CMS_SignerInfo *si,
135		const ASN1_OBJECT *obj, int lastpos)
136	0	{
137	0	return X509at_get_attr_by_OBJ(si->unsignedAttrs, obj, lastpos);
138	0	}
139
140		X509_ATTRIBUTE CMS_unsigned_get_attr(const CMS_SignerInfo si, int loc)
141	0	{
142	0	return X509at_get_attr(si->unsignedAttrs, loc);
143	0	}
144
145		X509_ATTRIBUTE CMS_unsigned_delete_attr(CMS_SignerInfo si, int loc)
146	0	{
147	0	return X509at_delete_attr(si->unsignedAttrs, loc);
148	0	}
149
150		int CMS_unsigned_add1_attr(CMS_SignerInfo si, X509_ATTRIBUTE attr)
151	0	{
152	0	if (ossl_x509at_add1_attr(&si->unsignedAttrs, attr))
153	0	return 1;
154	0	return 0;
155	0	}
156
157		int CMS_unsigned_add1_attr_by_OBJ(CMS_SignerInfo *si,
158		const ASN1_OBJECT *obj, int type,
159		const void *bytes, int len)
160	0	{
161	0	if (ossl_x509at_add1_attr_by_OBJ(&si->unsignedAttrs, obj, type, bytes, len))
162	0	return 1;
163	0	return 0;
164	0	}
165
166		int CMS_unsigned_add1_attr_by_NID(CMS_SignerInfo *si,
167		int nid, int type,
168		const void *bytes, int len)
169	0	{
170	0	if (ossl_x509at_add1_attr_by_NID(&si->unsignedAttrs, nid, type, bytes, len))
171	0	return 1;
172	0	return 0;
173	0	}
174
175		int CMS_unsigned_add1_attr_by_txt(CMS_SignerInfo *si,
176		const char *attrname, int type,
177		const void *bytes, int len)
178	0	{
179	0	if (ossl_x509at_add1_attr_by_txt(&si->unsignedAttrs, attrname,
180	0	type, bytes, len))
181	0	return 1;
182	0	return 0;
183	0	}
184
185		void CMS_unsigned_get0_data_by_OBJ(CMS_SignerInfo si, ASN1_OBJECT *oid,
186		int lastpos, int type)
187	0	{
188	0	return X509at_get0_data_by_OBJ(si->unsignedAttrs, oid, lastpos, type);
189	0	}
190
191		/*
192		* Retrieve an attribute by nid from a stack of attributes starting at index
193		* *lastpos + 1.
194		* Returns the attribute or NULL if there is no attribute.
195		* If an attribute was found *lastpos returns the index of the found attribute.
196		*/
197		static X509_ATTRIBUTE *cms_attrib_get(int nid,
198		const STACK_OF(X509_ATTRIBUTE) *attrs,
199		int *lastpos)
200	0	{
201	0	X509_ATTRIBUTE *at;
202	0	int loc;
203
204	0	loc = X509at_get_attr_by_NID(attrs, nid, *lastpos);
205	0	if (loc < 0)
206	0	return NULL;
207
208	0	at = X509at_get_attr(attrs, loc);
209	0	*lastpos = loc;
210	0	return at;
211	0	}
212
213		static int cms_check_attribute(int nid, int flags, int type,
214		const STACK_OF(X509_ATTRIBUTE) *attrs,
215		int have_attrs)
216	0	{
217	0	int lastpos = -1;
218	0	X509_ATTRIBUTE *at = cms_attrib_get(nid, attrs, &lastpos);
219
220	0	if (at != NULL) {
221	0	int count = X509_ATTRIBUTE_count(at);
222
223		/* Is this attribute allowed? */
224	0	if (((flags & type) == 0)
225		/* check if multiple attributes of the same type are allowed */
226	0	\|\| (((flags & CMS_ATTR_F_ONLY_ONE) != 0)
227	0	&& cms_attrib_get(nid, attrs, &lastpos) != NULL)
228		/* Check if attribute should have exactly one value in its set */
229	0	\|\| (((flags & CMS_ATTR_F_ONE_ATTR_VALUE) != 0)
230	0	&& count != 1)
231		/* There should be at least one value */
232	0	\|\| count == 0)
233	0	return 0;
234	0	} else {
235		/* fail if a required attribute is missing */
236	0	if (have_attrs
237	0	&& ((flags & CMS_ATTR_F_REQUIRED_COND) != 0)
238	0	&& (flags & type) != 0)
239	0	return 0;
240	0	}
241	0	return 1;
242	0	}
243
244		/*
245		* Check that the signerinfo attributes obey the attribute rules which includes
246		* the following checks
247		* - If any signed attributes exist then there must be a Content Type
248		* and Message Digest attribute in the signed attributes.
249		* - The countersignature attribute is an optional unsigned attribute only.
250		* - Content Type, Message Digest, and Signing time attributes are signed
251		* attributes. Only one instance of each is allowed, with each of these
252		* attributes containing a single attribute value in its set.
253		*/
254		int ossl_cms_si_check_attributes(const CMS_SignerInfo *si)
255	0	{
256	0	int i;
257	0	int have_signed_attrs = (CMS_signed_get_attr_count(si) > 0);
258	0	int have_unsigned_attrs = (CMS_unsigned_get_attr_count(si) > 0);
259
260	0	for (i = 0; i < (int)OSSL_NELEM(cms_attribute_properties); ++i) {
261	0	int nid = cms_attribute_properties[i].nid;
262	0	int flags = cms_attribute_properties[i].flags;
263
264	0	if (!cms_check_attribute(nid, flags, CMS_ATTR_F_SIGNED,
265	0	si->signedAttrs, have_signed_attrs)
266	0	\|\| !cms_check_attribute(nid, flags, CMS_ATTR_F_UNSIGNED,
267	0	si->unsignedAttrs, have_unsigned_attrs)) {
268	0	ERR_raise(ERR_LIB_CMS, CMS_R_ATTRIBUTE_ERROR);
269	0	return 0;
270	0	}
271	0	}
272	0	return 1;
273	0	}