/src/openssl32/crypto/cms/cms_pwri.c

Source (jump to first uncovered line)
/*
 * Copyright 2009-2021 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 "internal/cryptlib.h"
#include <openssl/asn1t.h>
#include <openssl/pem.h>
#include <openssl/x509v3.h>
#include <openssl/err.h>
#include <openssl/cms.h>
#include <openssl/rand.h>
#include <openssl/aes.h>
#include "internal/sizes.h"
#include "crypto/asn1.h"
#include "cms_local.h"

int CMS_RecipientInfo_set0_password(CMS_RecipientInfo *ri,
                                    unsigned char *pass, ossl_ssize_t passlen)
{
    CMS_PasswordRecipientInfo *pwri;
    if (ri->type != CMS_RECIPINFO_PASS) {
        ERR_raise(ERR_LIB_CMS, CMS_R_NOT_PWRI);
        return 0;
    }

    pwri = ri->d.pwri;
    pwri->pass = pass;
    if (pass && passlen < 0)
        passlen = strlen((char *)pass);
    pwri->passlen = passlen;
    return 1;
}

CMS_RecipientInfo *CMS_add0_recipient_password(CMS_ContentInfo *cms,
                                               int iter, int wrap_nid,
                                               int pbe_nid,
                                               unsigned char *pass,
                                               ossl_ssize_t passlen,
                                               const EVP_CIPHER *kekciph)
{
    STACK_OF(CMS_RecipientInfo) *ris;
    CMS_RecipientInfo *ri = NULL;
    CMS_EncryptedContentInfo *ec;
    CMS_PasswordRecipientInfo *pwri;
    EVP_CIPHER_CTX *ctx = NULL;
    X509_ALGOR *encalg = NULL;
    unsigned char iv[EVP_MAX_IV_LENGTH];
    int ivlen;
    const CMS_CTX *cms_ctx = ossl_cms_get0_cmsctx(cms);

    ec = ossl_cms_get0_env_enc_content(cms);
    if (ec == NULL)
        return NULL;
    ris = CMS_get0_RecipientInfos(cms);
    if (ris == NULL)
        return NULL;

    if (wrap_nid <= 0)
        wrap_nid = NID_id_alg_PWRI_KEK;

    if (pbe_nid <= 0)
        pbe_nid = NID_id_pbkdf2;

    /* Get from enveloped data */
    if (kekciph == NULL)
        kekciph = ec->cipher;

    if (kekciph == NULL) {
        ERR_raise(ERR_LIB_CMS, CMS_R_NO_CIPHER);
        return NULL;
    }
    if (wrap_nid != NID_id_alg_PWRI_KEK) {
        ERR_raise(ERR_LIB_CMS, CMS_R_UNSUPPORTED_KEY_ENCRYPTION_ALGORITHM);
        return NULL;
    }

    /* Setup algorithm identifier for cipher */
    encalg = X509_ALGOR_new();
    if (encalg == NULL) {
        ERR_raise(ERR_LIB_CMS, ERR_R_ASN1_LIB);
        goto err;
    }
    ctx = EVP_CIPHER_CTX_new();
    if (ctx == NULL) {
        ERR_raise(ERR_LIB_CMS, ERR_R_EVP_LIB);
        goto err;
    }

    if (EVP_EncryptInit_ex(ctx, kekciph, NULL, NULL, NULL) <= 0) {
        ERR_raise(ERR_LIB_CMS, ERR_R_EVP_LIB);
        goto err;
    }

    ivlen = EVP_CIPHER_CTX_get_iv_length(ctx);
    if (ivlen < 0) {
        ERR_raise(ERR_LIB_CMS, ERR_R_EVP_LIB);
        goto err;
    }

    if (ivlen > 0) {
        if (RAND_bytes_ex(ossl_cms_ctx_get0_libctx(cms_ctx), iv, ivlen, 0) <= 0)
            goto err;
        if (EVP_EncryptInit_ex(ctx, NULL, NULL, NULL, iv) <= 0) {
            ERR_raise(ERR_LIB_CMS, ERR_R_EVP_LIB);
            goto err;
        }
        encalg->parameter = ASN1_TYPE_new();
        if (!encalg->parameter) {
            ERR_raise(ERR_LIB_CMS, ERR_R_ASN1_LIB);
            goto err;
        }
        if (EVP_CIPHER_param_to_asn1(ctx, encalg->parameter) <= 0) {
            ERR_raise(ERR_LIB_CMS, CMS_R_CIPHER_PARAMETER_INITIALISATION_ERROR);
            goto err;
        }
    }

    encalg->algorithm = OBJ_nid2obj(EVP_CIPHER_CTX_get_type(ctx));

    EVP_CIPHER_CTX_free(ctx);
    ctx = NULL;

    /* Initialize recipient info */
    ri = M_ASN1_new_of(CMS_RecipientInfo);
    if (ri == NULL) {
        ERR_raise(ERR_LIB_CMS, ERR_R_ASN1_LIB);
        goto err;
    }

    ri->d.pwri = M_ASN1_new_of(CMS_PasswordRecipientInfo);
    if (ri->d.pwri == NULL) {
        ERR_raise(ERR_LIB_CMS, ERR_R_ASN1_LIB);
        goto err;
    }
    ri->type = CMS_RECIPINFO_PASS;

    pwri = ri->d.pwri;
    pwri->cms_ctx = cms_ctx;
    /* Since this is overwritten, free up empty structure already there */
    X509_ALGOR_free(pwri->keyEncryptionAlgorithm);
    pwri->keyEncryptionAlgorithm = X509_ALGOR_new();
    if (pwri->keyEncryptionAlgorithm == NULL) {
        ERR_raise(ERR_LIB_CMS, ERR_R_ASN1_LIB);
        goto err;
    }
    pwri->keyEncryptionAlgorithm->algorithm = OBJ_nid2obj(wrap_nid);
    pwri->keyEncryptionAlgorithm->parameter = ASN1_TYPE_new();
    if (pwri->keyEncryptionAlgorithm->parameter == NULL) {
        ERR_raise(ERR_LIB_CMS, ERR_R_ASN1_LIB);
        goto err;
    }

    if (!ASN1_item_pack(encalg, ASN1_ITEM_rptr(X509_ALGOR),
                        &pwri->keyEncryptionAlgorithm->parameter->
                        value.sequence)) {
        ERR_raise(ERR_LIB_CMS, ERR_R_ASN1_LIB);
        goto err;
    }
    pwri->keyEncryptionAlgorithm->parameter->type = V_ASN1_SEQUENCE;

    X509_ALGOR_free(encalg);
    encalg = NULL;

    /* Setup PBE algorithm */

    pwri->keyDerivationAlgorithm = PKCS5_pbkdf2_set(iter, NULL, 0, -1, -1);

    if (pwri->keyDerivationAlgorithm == NULL)
        goto err;

    CMS_RecipientInfo_set0_password(ri, pass, passlen);
    pwri->version = 0;

    if (!sk_CMS_RecipientInfo_push(ris, ri)) {
        ERR_raise(ERR_LIB_CMS, ERR_R_CRYPTO_LIB);
        goto err;
    }

    return ri;

 err:
    EVP_CIPHER_CTX_free(ctx);
    if (ri)
        M_ASN1_free_of(ri, CMS_RecipientInfo);
    X509_ALGOR_free(encalg);
    return NULL;

}

/*
 * This is an implementation of the key wrapping mechanism in RFC3211, at
 * some point this should go into EVP.
 */

static int kek_unwrap_key(unsigned char *out, size_t *outlen,
                          const unsigned char *in, size_t inlen,
                          EVP_CIPHER_CTX *ctx)
{
    size_t blocklen = EVP_CIPHER_CTX_get_block_size(ctx);
    unsigned char *tmp;
    int outl, rv = 0;
    if (inlen < 2 * blocklen) {
        /* too small */
        return 0;
    }
    if (inlen % blocklen) {
        /* Invalid size */
        return 0;
    }
    if ((tmp = OPENSSL_malloc(inlen)) == NULL)
        return 0;
    /* setup IV by decrypting last two blocks */
    if (!EVP_DecryptUpdate(ctx, tmp + inlen - 2 * blocklen, &outl,
                           in + inlen - 2 * blocklen, blocklen * 2)
        /*
         * Do a decrypt of last decrypted block to set IV to correct value
         * output it to start of buffer so we don't corrupt decrypted block
         * this works because buffer is at least two block lengths long.
         */
        || !EVP_DecryptUpdate(ctx, tmp, &outl,
                              tmp + inlen - blocklen, blocklen)
        /* Can now decrypt first n - 1 blocks */
        || !EVP_DecryptUpdate(ctx, tmp, &outl, in, inlen - blocklen)

        /* Reset IV to original value */
        || !EVP_DecryptInit_ex(ctx, NULL, NULL, NULL, NULL)
        /* Decrypt again */
        || !EVP_DecryptUpdate(ctx, tmp, &outl, tmp, inlen))
        goto err;
    /* Check check bytes */
    if (((tmp[1] ^ tmp[4]) & (tmp[2] ^ tmp[5]) & (tmp[3] ^ tmp[6])) != 0xff) {
        /* Check byte failure */
        goto err;
    }
    if (inlen < (size_t)(tmp[0] - 4)) {
        /* Invalid length value */
        goto err;
    }
    *outlen = (size_t)tmp[0];
    memcpy(out, tmp + 4, *outlen);
    rv = 1;
 err:
    OPENSSL_clear_free(tmp, inlen);
    return rv;

}

static int kek_wrap_key(unsigned char *out, size_t *outlen,
                        const unsigned char *in, size_t inlen,
                        EVP_CIPHER_CTX *ctx, const CMS_CTX *cms_ctx)
{
    size_t blocklen = EVP_CIPHER_CTX_get_block_size(ctx);
    size_t olen;
    int dummy;
    /*
     * First decide length of output buffer: need header and round up to
     * multiple of block length.
     */
    olen = (inlen + 4 + blocklen - 1) / blocklen;
    olen *= blocklen;
    if (olen < 2 * blocklen) {
        /* Key too small */
        return 0;
    }
    if (inlen > 0xFF) {
        /* Key too large */
        return 0;
    }
    if (out) {
        /* Set header */
        out[0] = (unsigned char)inlen;
        out[1] = in[0] ^ 0xFF;
        out[2] = in[1] ^ 0xFF;
        out[3] = in[2] ^ 0xFF;
        memcpy(out + 4, in, inlen);
        /* Add random padding to end */
        if (olen > inlen + 4
            && RAND_bytes_ex(ossl_cms_ctx_get0_libctx(cms_ctx), out + 4 + inlen,
                             olen - 4 - inlen, 0) <= 0)
            return 0;
        /* Encrypt twice */
        if (!EVP_EncryptUpdate(ctx, out, &dummy, out, olen)
            || !EVP_EncryptUpdate(ctx, out, &dummy, out, olen))
            return 0;
    }

    *outlen = olen;

    return 1;
}

/* Encrypt/Decrypt content key in PWRI recipient info */

int ossl_cms_RecipientInfo_pwri_crypt(const CMS_ContentInfo *cms,
                                      CMS_RecipientInfo *ri, int en_de)
{
    CMS_EncryptedContentInfo *ec;
    CMS_PasswordRecipientInfo *pwri;
    int r = 0;
    X509_ALGOR *algtmp, *kekalg = NULL;
    EVP_CIPHER_CTX *kekctx = NULL;
    char name[OSSL_MAX_NAME_SIZE];
    EVP_CIPHER *kekcipher;
    unsigned char *key = NULL;
    size_t keylen;
    const CMS_CTX *cms_ctx = ossl_cms_get0_cmsctx(cms);

    ec = ossl_cms_get0_env_enc_content(cms);

    pwri = ri->d.pwri;

    if (pwri->pass == NULL) {
        ERR_raise(ERR_LIB_CMS, CMS_R_NO_PASSWORD);
        return 0;
    }
    algtmp = pwri->keyEncryptionAlgorithm;

    if (!algtmp || OBJ_obj2nid(algtmp->algorithm) != NID_id_alg_PWRI_KEK) {
        ERR_raise(ERR_LIB_CMS, CMS_R_UNSUPPORTED_KEY_ENCRYPTION_ALGORITHM);
        return 0;
    }

    kekalg = ASN1_TYPE_unpack_sequence(ASN1_ITEM_rptr(X509_ALGOR),
                                       algtmp->parameter);

    if (kekalg == NULL) {
        ERR_raise(ERR_LIB_CMS, CMS_R_INVALID_KEY_ENCRYPTION_PARAMETER);
        return 0;
    }

    OBJ_obj2txt(name, sizeof(name), kekalg->algorithm, 0);
    kekcipher = EVP_CIPHER_fetch(ossl_cms_ctx_get0_libctx(cms_ctx), name,
                                 ossl_cms_ctx_get0_propq(cms_ctx));

    if (kekcipher == NULL) {
        ERR_raise(ERR_LIB_CMS, CMS_R_UNKNOWN_CIPHER);
        goto err;
    }

    kekctx = EVP_CIPHER_CTX_new();
    if (kekctx == NULL) {
        ERR_raise(ERR_LIB_CMS, ERR_R_EVP_LIB);
        goto err;
    }
    /* Fixup cipher based on AlgorithmIdentifier to set IV etc */
    if (!EVP_CipherInit_ex(kekctx, kekcipher, NULL, NULL, NULL, en_de))
        goto err;
    EVP_CIPHER_CTX_set_padding(kekctx, 0);
    if (EVP_CIPHER_asn1_to_param(kekctx, kekalg->parameter) <= 0) {
        ERR_raise(ERR_LIB_CMS, CMS_R_CIPHER_PARAMETER_INITIALISATION_ERROR);
        goto err;
    }

    algtmp = pwri->keyDerivationAlgorithm;

    /* Finish password based key derivation to setup key in "ctx" */

    if (EVP_PBE_CipherInit(algtmp->algorithm,
                           (char *)pwri->pass, pwri->passlen,
                           algtmp->parameter, kekctx, en_de) < 0) {
        ERR_raise(ERR_LIB_CMS, ERR_R_EVP_LIB);
        goto err;
    }

    /* Finally wrap/unwrap the key */

    if (en_de) {

        if (!kek_wrap_key(NULL, &keylen, ec->key, ec->keylen, kekctx, cms_ctx))
            goto err;

        key = OPENSSL_malloc(keylen);

        if (key == NULL)
            goto err;

        if (!kek_wrap_key(key, &keylen, ec->key, ec->keylen, kekctx, cms_ctx))
            goto err;
        pwri->encryptedKey->data = key;
        pwri->encryptedKey->length = keylen;
    } else {
        key = OPENSSL_malloc(pwri->encryptedKey->length);
        if (key == NULL)
            goto err;
        if (!kek_unwrap_key(key, &keylen,
                            pwri->encryptedKey->data,
                            pwri->encryptedKey->length, kekctx)) {
            ERR_raise(ERR_LIB_CMS, CMS_R_UNWRAP_FAILURE);
            goto err;
        }

        OPENSSL_clear_free(ec->key, ec->keylen);
        ec->key = key;
        ec->keylen = keylen;

    }

    r = 1;

 err:
    EVP_CIPHER_free(kekcipher);
    EVP_CIPHER_CTX_free(kekctx);

    if (!r)
        OPENSSL_free(key);
    X509_ALGOR_free(kekalg);

    return r;

}

Coverage Report

Created: 2024-07-27 06:39

Line	Count	Source (jump to first uncovered line)
1		/*
2		* Copyright 2009-2021 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 "internal/cryptlib.h"
11		#include <openssl/asn1t.h>
12		#include <openssl/pem.h>
13		#include <openssl/x509v3.h>
14		#include <openssl/err.h>
15		#include <openssl/cms.h>
16		#include <openssl/rand.h>
17		#include <openssl/aes.h>
18		#include "internal/sizes.h"
19		#include "crypto/asn1.h"
20		#include "cms_local.h"
21
22		int CMS_RecipientInfo_set0_password(CMS_RecipientInfo *ri,
23		unsigned char *pass, ossl_ssize_t passlen)
24	0	{
25	0	CMS_PasswordRecipientInfo *pwri;
26	0	if (ri->type != CMS_RECIPINFO_PASS) {
27	0	ERR_raise(ERR_LIB_CMS, CMS_R_NOT_PWRI);
28	0	return 0;
29	0	}
30
31	0	pwri = ri->d.pwri;
32	0	pwri->pass = pass;
33	0	if (pass && passlen < 0)
34	0	passlen = strlen((char *)pass);
35	0	pwri->passlen = passlen;
36	0	return 1;
37	0	}
38
39		CMS_RecipientInfo CMS_add0_recipient_password(CMS_ContentInfo cms,
40		int iter, int wrap_nid,
41		int pbe_nid,
42		unsigned char *pass,
43		ossl_ssize_t passlen,
44		const EVP_CIPHER *kekciph)
45	0	{
46	0	STACK_OF(CMS_RecipientInfo) *ris;
47	0	CMS_RecipientInfo *ri = NULL;
48	0	CMS_EncryptedContentInfo *ec;
49	0	CMS_PasswordRecipientInfo *pwri;
50	0	EVP_CIPHER_CTX *ctx = NULL;
51	0	X509_ALGOR *encalg = NULL;
52	0	unsigned char iv[EVP_MAX_IV_LENGTH];
53	0	int ivlen;
54	0	const CMS_CTX *cms_ctx = ossl_cms_get0_cmsctx(cms);
55
56	0	ec = ossl_cms_get0_env_enc_content(cms);
57	0	if (ec == NULL)
58	0	return NULL;
59	0	ris = CMS_get0_RecipientInfos(cms);
60	0	if (ris == NULL)
61	0	return NULL;
62
63	0	if (wrap_nid <= 0)
64	0	wrap_nid = NID_id_alg_PWRI_KEK;
65
66	0	if (pbe_nid <= 0)
67	0	pbe_nid = NID_id_pbkdf2;
68
69		/* Get from enveloped data */
70	0	if (kekciph == NULL)
71	0	kekciph = ec->cipher;
72
73	0	if (kekciph == NULL) {
74	0	ERR_raise(ERR_LIB_CMS, CMS_R_NO_CIPHER);
75	0	return NULL;
76	0	}
77	0	if (wrap_nid != NID_id_alg_PWRI_KEK) {
78	0	ERR_raise(ERR_LIB_CMS, CMS_R_UNSUPPORTED_KEY_ENCRYPTION_ALGORITHM);
79	0	return NULL;
80	0	}
81
82		/* Setup algorithm identifier for cipher */
83	0	encalg = X509_ALGOR_new();
84	0	if (encalg == NULL) {
85	0	ERR_raise(ERR_LIB_CMS, ERR_R_ASN1_LIB);
86	0	goto err;
87	0	}
88	0	ctx = EVP_CIPHER_CTX_new();
89	0	if (ctx == NULL) {
90	0	ERR_raise(ERR_LIB_CMS, ERR_R_EVP_LIB);
91	0	goto err;
92	0	}
93
94	0	if (EVP_EncryptInit_ex(ctx, kekciph, NULL, NULL, NULL) <= 0) {
95	0	ERR_raise(ERR_LIB_CMS, ERR_R_EVP_LIB);
96	0	goto err;
97	0	}
98
99	0	ivlen = EVP_CIPHER_CTX_get_iv_length(ctx);
100	0	if (ivlen < 0) {
101	0	ERR_raise(ERR_LIB_CMS, ERR_R_EVP_LIB);
102	0	goto err;
103	0	}
104
105	0	if (ivlen > 0) {
106	0	if (RAND_bytes_ex(ossl_cms_ctx_get0_libctx(cms_ctx), iv, ivlen, 0) <= 0)
107	0	goto err;
108	0	if (EVP_EncryptInit_ex(ctx, NULL, NULL, NULL, iv) <= 0) {
109	0	ERR_raise(ERR_LIB_CMS, ERR_R_EVP_LIB);
110	0	goto err;
111	0	}
112	0	encalg->parameter = ASN1_TYPE_new();
113	0	if (!encalg->parameter) {
114	0	ERR_raise(ERR_LIB_CMS, ERR_R_ASN1_LIB);
115	0	goto err;
116	0	}
117	0	if (EVP_CIPHER_param_to_asn1(ctx, encalg->parameter) <= 0) {
118	0	ERR_raise(ERR_LIB_CMS, CMS_R_CIPHER_PARAMETER_INITIALISATION_ERROR);
119	0	goto err;
120	0	}
121	0	}
122
123	0	encalg->algorithm = OBJ_nid2obj(EVP_CIPHER_CTX_get_type(ctx));
124
125	0	EVP_CIPHER_CTX_free(ctx);
126	0	ctx = NULL;
127
128		/* Initialize recipient info */
129	0	ri = M_ASN1_new_of(CMS_RecipientInfo);
130	0	if (ri == NULL) {
131	0	ERR_raise(ERR_LIB_CMS, ERR_R_ASN1_LIB);
132	0	goto err;
133	0	}
134
135	0	ri->d.pwri = M_ASN1_new_of(CMS_PasswordRecipientInfo);
136	0	if (ri->d.pwri == NULL) {
137	0	ERR_raise(ERR_LIB_CMS, ERR_R_ASN1_LIB);
138	0	goto err;
139	0	}
140	0	ri->type = CMS_RECIPINFO_PASS;
141
142	0	pwri = ri->d.pwri;
143	0	pwri->cms_ctx = cms_ctx;
144		/* Since this is overwritten, free up empty structure already there */
145	0	X509_ALGOR_free(pwri->keyEncryptionAlgorithm);
146	0	pwri->keyEncryptionAlgorithm = X509_ALGOR_new();
147	0	if (pwri->keyEncryptionAlgorithm == NULL) {
148	0	ERR_raise(ERR_LIB_CMS, ERR_R_ASN1_LIB);
149	0	goto err;
150	0	}
151	0	pwri->keyEncryptionAlgorithm->algorithm = OBJ_nid2obj(wrap_nid);
152	0	pwri->keyEncryptionAlgorithm->parameter = ASN1_TYPE_new();
153	0	if (pwri->keyEncryptionAlgorithm->parameter == NULL) {
154	0	ERR_raise(ERR_LIB_CMS, ERR_R_ASN1_LIB);
155	0	goto err;
156	0	}
157
158	0	if (!ASN1_item_pack(encalg, ASN1_ITEM_rptr(X509_ALGOR),
159	0	&pwri->keyEncryptionAlgorithm->parameter->
160	0	value.sequence)) {
161	0	ERR_raise(ERR_LIB_CMS, ERR_R_ASN1_LIB);
162	0	goto err;
163	0	}
164	0	pwri->keyEncryptionAlgorithm->parameter->type = V_ASN1_SEQUENCE;
165
166	0	X509_ALGOR_free(encalg);
167	0	encalg = NULL;
168
169		/* Setup PBE algorithm */
170
171	0	pwri->keyDerivationAlgorithm = PKCS5_pbkdf2_set(iter, NULL, 0, -1, -1);
172
173	0	if (pwri->keyDerivationAlgorithm == NULL)
174	0	goto err;
175
176	0	CMS_RecipientInfo_set0_password(ri, pass, passlen);
177	0	pwri->version = 0;
178
179	0	if (!sk_CMS_RecipientInfo_push(ris, ri)) {
180	0	ERR_raise(ERR_LIB_CMS, ERR_R_CRYPTO_LIB);
181	0	goto err;
182	0	}
183
184	0	return ri;
185
186	0	err:
187	0	EVP_CIPHER_CTX_free(ctx);
188	0	if (ri)
189	0	M_ASN1_free_of(ri, CMS_RecipientInfo);
190	0	X509_ALGOR_free(encalg);
191	0	return NULL;
192
193	0	}
194
195		/*
196		* This is an implementation of the key wrapping mechanism in RFC3211, at
197		* some point this should go into EVP.
198		*/
199
200		static int kek_unwrap_key(unsigned char out, size_t outlen,
201		const unsigned char *in, size_t inlen,
202		EVP_CIPHER_CTX *ctx)
203	0	{
204	0	size_t blocklen = EVP_CIPHER_CTX_get_block_size(ctx);
205	0	unsigned char *tmp;
206	0	int outl, rv = 0;
207	0	if (inlen < 2 * blocklen) {
208		/* too small */
209	0	return 0;
210	0	}
211	0	if (inlen % blocklen) {
212		/* Invalid size */
213	0	return 0;
214	0	}
215	0	if ((tmp = OPENSSL_malloc(inlen)) == NULL)
216	0	return 0;
217		/* setup IV by decrypting last two blocks */
218	0	if (!EVP_DecryptUpdate(ctx, tmp + inlen - 2 * blocklen, &outl,
219	0	in + inlen - 2 * blocklen, blocklen * 2)
220		/*
221		* Do a decrypt of last decrypted block to set IV to correct value
222		* output it to start of buffer so we don't corrupt decrypted block
223		* this works because buffer is at least two block lengths long.
224		*/
225	0	\|\| !EVP_DecryptUpdate(ctx, tmp, &outl,
226	0	tmp + inlen - blocklen, blocklen)
227		/* Can now decrypt first n - 1 blocks */
228	0	\|\| !EVP_DecryptUpdate(ctx, tmp, &outl, in, inlen - blocklen)
229
230		/* Reset IV to original value */
231	0	\|\| !EVP_DecryptInit_ex(ctx, NULL, NULL, NULL, NULL)
232		/* Decrypt again */
233	0	\|\| !EVP_DecryptUpdate(ctx, tmp, &outl, tmp, inlen))
234	0	goto err;
235		/* Check check bytes */
236	0	if (((tmp[1] ^ tmp[4]) & (tmp[2] ^ tmp[5]) & (tmp[3] ^ tmp[6])) != 0xff) {
237		/* Check byte failure */
238	0	goto err;
239	0	}
240	0	if (inlen < (size_t)(tmp[0] - 4)) {
241		/* Invalid length value */
242	0	goto err;
243	0	}
244	0	*outlen = (size_t)tmp[0];
245	0	memcpy(out, tmp + 4, *outlen);
246	0	rv = 1;
247	0	err:
248	0	OPENSSL_clear_free(tmp, inlen);
249	0	return rv;
250
251	0	}
252
253		static int kek_wrap_key(unsigned char out, size_t outlen,
254		const unsigned char *in, size_t inlen,
255		EVP_CIPHER_CTX ctx, const CMS_CTX cms_ctx)
256	0	{
257	0	size_t blocklen = EVP_CIPHER_CTX_get_block_size(ctx);
258	0	size_t olen;
259	0	int dummy;
260		/*
261		* First decide length of output buffer: need header and round up to
262		* multiple of block length.
263		*/
264	0	olen = (inlen + 4 + blocklen - 1) / blocklen;
265	0	olen *= blocklen;
266	0	if (olen < 2 * blocklen) {
267		/* Key too small */
268	0	return 0;
269	0	}
270	0	if (inlen > 0xFF) {
271		/* Key too large */
272	0	return 0;
273	0	}
274	0	if (out) {
275		/* Set header */
276	0	out[0] = (unsigned char)inlen;
277	0	out[1] = in[0] ^ 0xFF;
278	0	out[2] = in[1] ^ 0xFF;
279	0	out[3] = in[2] ^ 0xFF;
280	0	memcpy(out + 4, in, inlen);
281		/* Add random padding to end */
282	0	if (olen > inlen + 4
283	0	&& RAND_bytes_ex(ossl_cms_ctx_get0_libctx(cms_ctx), out + 4 + inlen,
284	0	olen - 4 - inlen, 0) <= 0)
285	0	return 0;
286		/* Encrypt twice */
287	0	if (!EVP_EncryptUpdate(ctx, out, &dummy, out, olen)
288	0	\|\| !EVP_EncryptUpdate(ctx, out, &dummy, out, olen))
289	0	return 0;
290	0	}
291
292	0	*outlen = olen;
293
294	0	return 1;
295	0	}
296
297		/* Encrypt/Decrypt content key in PWRI recipient info */
298
299		int ossl_cms_RecipientInfo_pwri_crypt(const CMS_ContentInfo *cms,
300		CMS_RecipientInfo *ri, int en_de)
301	0	{
302	0	CMS_EncryptedContentInfo *ec;
303	0	CMS_PasswordRecipientInfo *pwri;
304	0	int r = 0;
305	0	X509_ALGOR algtmp, kekalg = NULL;
306	0	EVP_CIPHER_CTX *kekctx = NULL;
307	0	char name[OSSL_MAX_NAME_SIZE];
308	0	EVP_CIPHER *kekcipher;
309	0	unsigned char *key = NULL;
310	0	size_t keylen;
311	0	const CMS_CTX *cms_ctx = ossl_cms_get0_cmsctx(cms);
312
313	0	ec = ossl_cms_get0_env_enc_content(cms);
314
315	0	pwri = ri->d.pwri;
316
317	0	if (pwri->pass == NULL) {
318	0	ERR_raise(ERR_LIB_CMS, CMS_R_NO_PASSWORD);
319	0	return 0;
320	0	}
321	0	algtmp = pwri->keyEncryptionAlgorithm;
322
323	0	if (!algtmp \|\| OBJ_obj2nid(algtmp->algorithm) != NID_id_alg_PWRI_KEK) {
324	0	ERR_raise(ERR_LIB_CMS, CMS_R_UNSUPPORTED_KEY_ENCRYPTION_ALGORITHM);
325	0	return 0;
326	0	}
327
328	0	kekalg = ASN1_TYPE_unpack_sequence(ASN1_ITEM_rptr(X509_ALGOR),
329	0	algtmp->parameter);
330
331	0	if (kekalg == NULL) {
332	0	ERR_raise(ERR_LIB_CMS, CMS_R_INVALID_KEY_ENCRYPTION_PARAMETER);
333	0	return 0;
334	0	}
335
336	0	OBJ_obj2txt(name, sizeof(name), kekalg->algorithm, 0);
337	0	kekcipher = EVP_CIPHER_fetch(ossl_cms_ctx_get0_libctx(cms_ctx), name,
338	0	ossl_cms_ctx_get0_propq(cms_ctx));
339
340	0	if (kekcipher == NULL) {
341	0	ERR_raise(ERR_LIB_CMS, CMS_R_UNKNOWN_CIPHER);
342	0	goto err;
343	0	}
344
345	0	kekctx = EVP_CIPHER_CTX_new();
346	0	if (kekctx == NULL) {
347	0	ERR_raise(ERR_LIB_CMS, ERR_R_EVP_LIB);
348	0	goto err;
349	0	}
350		/* Fixup cipher based on AlgorithmIdentifier to set IV etc */
351	0	if (!EVP_CipherInit_ex(kekctx, kekcipher, NULL, NULL, NULL, en_de))
352	0	goto err;
353	0	EVP_CIPHER_CTX_set_padding(kekctx, 0);
354	0	if (EVP_CIPHER_asn1_to_param(kekctx, kekalg->parameter) <= 0) {
355	0	ERR_raise(ERR_LIB_CMS, CMS_R_CIPHER_PARAMETER_INITIALISATION_ERROR);
356	0	goto err;
357	0	}
358
359	0	algtmp = pwri->keyDerivationAlgorithm;
360
361		/* Finish password based key derivation to setup key in "ctx" */
362
363	0	if (EVP_PBE_CipherInit(algtmp->algorithm,
364	0	(char *)pwri->pass, pwri->passlen,
365	0	algtmp->parameter, kekctx, en_de) < 0) {
366	0	ERR_raise(ERR_LIB_CMS, ERR_R_EVP_LIB);
367	0	goto err;
368	0	}
369
370		/* Finally wrap/unwrap the key */
371
372	0	if (en_de) {
373
374	0	if (!kek_wrap_key(NULL, &keylen, ec->key, ec->keylen, kekctx, cms_ctx))
375	0	goto err;
376
377	0	key = OPENSSL_malloc(keylen);
378
379	0	if (key == NULL)
380	0	goto err;
381
382	0	if (!kek_wrap_key(key, &keylen, ec->key, ec->keylen, kekctx, cms_ctx))
383	0	goto err;
384	0	pwri->encryptedKey->data = key;
385	0	pwri->encryptedKey->length = keylen;
386	0	} else {
387	0	key = OPENSSL_malloc(pwri->encryptedKey->length);
388	0	if (key == NULL)
389	0	goto err;
390	0	if (!kek_unwrap_key(key, &keylen,
391	0	pwri->encryptedKey->data,
392	0	pwri->encryptedKey->length, kekctx)) {
393	0	ERR_raise(ERR_LIB_CMS, CMS_R_UNWRAP_FAILURE);
394	0	goto err;
395	0	}
396
397	0	OPENSSL_clear_free(ec->key, ec->keylen);
398	0	ec->key = key;
399	0	ec->keylen = keylen;
400
401	0	}
402
403	0	r = 1;
404
405	0	err:
406	0	EVP_CIPHER_free(kekcipher);
407	0	EVP_CIPHER_CTX_free(kekctx);
408
409	0	if (!r)
410	0	OPENSSL_free(key);
411	0	X509_ALGOR_free(kekalg);
412
413	0	return r;
414
415	0	}