1/*
2 * Copyright 1999-2021 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 <stdio.h>
11#include "internal/cryptlib.h"
12#include <openssl/pkcs12.h>
13#include "crypto/x509.h" /* for ossl_x509_add_cert_new() */
14
15/* Simplified PKCS#12 routines */
16
17static int parse_pk12(PKCS12 *p12, const char *pass, int passlen,
18                      EVP_PKEY **pkey, STACK_OF(X509) *ocerts);
19
20static int parse_bags(const STACK_OF(PKCS12_SAFEBAG) *bags, const char *pass,
21                      int passlen, EVP_PKEY **pkey, STACK_OF(X509) *ocerts);
22
23static int parse_bag(PKCS12_SAFEBAG *bag, const char *pass, int passlen,
24                     EVP_PKEY **pkey, STACK_OF(X509) *ocerts);
25
26/*
27 * Parse and decrypt a PKCS#12 structure returning user key, user cert and
28 * other (CA) certs. Note either ca should be NULL, *ca should be NULL, or it
29 * should point to a valid STACK structure. pkey and/or cert may be NULL;
30 * if non-NULL the variables they point to can be passed uninitialised.
31 */
32
33int PKCS12_parse(PKCS12 *p12, const char *pass, EVP_PKEY **pkey, X509 **cert,
34                 STACK_OF(X509) **ca)
35{
36    STACK_OF(X509) *ocerts = NULL;
37    X509 *x = NULL;
38
39    if (pkey != NULL)
40        *pkey = NULL;
41    if (cert != NULL)
42        *cert = NULL;
43
44    /* Check for NULL PKCS12 structure */
45
46    if (p12 == NULL) {
47        ERR_raise(ERR_LIB_PKCS12, PKCS12_R_INVALID_NULL_PKCS12_POINTER);
48        return 0;
49    }
50
51    /* Check the mac */
52
53    /*
54     * If password is zero length or NULL then try verifying both cases to
55     * determine which password is correct. The reason for this is that under
56     * PKCS#12 password based encryption no password and a zero length
57     * password are two different things...
58     */
59
60    if (pass == NULL || *pass == '\0') {
61        if (!PKCS12_mac_present(p12)
62            || PKCS12_verify_mac(p12, NULL, 0))
63            pass = NULL;
64        else if (PKCS12_verify_mac(p12, "", 0))
65            pass = "";
66        else {
67            ERR_raise(ERR_LIB_PKCS12, PKCS12_R_MAC_VERIFY_FAILURE);
68            goto err;
69        }
70    } else if (!PKCS12_verify_mac(p12, pass, -1)) {
71        ERR_raise(ERR_LIB_PKCS12, PKCS12_R_MAC_VERIFY_FAILURE);
72        goto err;
73    }
74
75    /* If needed, allocate stack for other certificates */
76    if ((cert != NULL || ca != NULL)
77            && (ocerts = sk_X509_new_null()) == NULL) {
78        ERR_raise(ERR_LIB_PKCS12, ERR_R_MALLOC_FAILURE);
79        goto err;
80    }
81
82    if (!parse_pk12(p12, pass, -1, pkey, ocerts)) {
83        int err = ERR_peek_last_error();
84
85        if (ERR_GET_LIB(err) != ERR_LIB_EVP
86                && ERR_GET_REASON(err) != EVP_R_UNSUPPORTED_ALGORITHM)
87            ERR_raise(ERR_LIB_PKCS12, PKCS12_R_PARSE_ERROR);
88        goto err;
89    }
90
91    /* Split the certs in ocerts over *cert and *ca as far as requested */
92    while ((x = sk_X509_shift(ocerts)) != NULL) {
93        if (pkey != NULL && *pkey != NULL
94                && cert != NULL && *cert == NULL) {
95            int match;
96
97            ERR_set_mark();
98            match = X509_check_private_key(x, *pkey);
99            ERR_pop_to_mark();
100            if (match) {
101                *cert = x;
102                continue;
103            }
104        }
105
106        if (ca != NULL) {
107            if (!ossl_x509_add_cert_new(ca, x, X509_ADD_FLAG_DEFAULT))
108                goto err;
109            continue;
110        }
111        X509_free(x);
112    }
113    sk_X509_free(ocerts);
114
115    return 1;
116
117 err:
118
119    if (pkey != NULL) {
120        EVP_PKEY_free(*pkey);
121        *pkey = NULL;
122    }
123    if (cert != NULL) {
124        X509_free(*cert);
125        *cert = NULL;
126    }
127    X509_free(x);
128    sk_X509_pop_free(ocerts, X509_free);
129    return 0;
130
131}
132
133/* Parse the outer PKCS#12 structure */
134
135/* pkey and/or ocerts may be NULL */
136static int parse_pk12(PKCS12 *p12, const char *pass, int passlen,
137                      EVP_PKEY **pkey, STACK_OF(X509) *ocerts)
138{
139    STACK_OF(PKCS7) *asafes;
140    STACK_OF(PKCS12_SAFEBAG) *bags;
141    int i, bagnid;
142    PKCS7 *p7;
143
144    if ((asafes = PKCS12_unpack_authsafes(p12)) == NULL)
145        return 0;
146    for (i = 0; i < sk_PKCS7_num(asafes); i++) {
147        p7 = sk_PKCS7_value(asafes, i);
148        bagnid = OBJ_obj2nid(p7->type);
149        if (bagnid == NID_pkcs7_data) {
150            bags = PKCS12_unpack_p7data(p7);
151        } else if (bagnid == NID_pkcs7_encrypted) {
152            bags = PKCS12_unpack_p7encdata(p7, pass, passlen);
153        } else
154            continue;
155        if (!bags) {
156            sk_PKCS7_pop_free(asafes, PKCS7_free);
157            return 0;
158        }
159        if (!parse_bags(bags, pass, passlen, pkey, ocerts)) {
160            sk_PKCS12_SAFEBAG_pop_free(bags, PKCS12_SAFEBAG_free);
161            sk_PKCS7_pop_free(asafes, PKCS7_free);
162            return 0;
163        }
164        sk_PKCS12_SAFEBAG_pop_free(bags, PKCS12_SAFEBAG_free);
165    }
166    sk_PKCS7_pop_free(asafes, PKCS7_free);
167    return 1;
168}
169
170/* pkey and/or ocerts may be NULL */
171static int parse_bags(const STACK_OF(PKCS12_SAFEBAG) *bags, const char *pass,
172                      int passlen, EVP_PKEY **pkey, STACK_OF(X509) *ocerts)
173{
174    int i;
175    for (i = 0; i < sk_PKCS12_SAFEBAG_num(bags); i++) {
176        if (!parse_bag(sk_PKCS12_SAFEBAG_value(bags, i),
177                       pass, passlen, pkey, ocerts))
178            return 0;
179    }
180    return 1;
181}
182
183/* pkey and/or ocerts may be NULL */
184static int parse_bag(PKCS12_SAFEBAG *bag, const char *pass, int passlen,
185                     EVP_PKEY **pkey, STACK_OF(X509) *ocerts)
186{
187    PKCS8_PRIV_KEY_INFO *p8;
188    X509 *x509;
189    const ASN1_TYPE *attrib;
190    ASN1_BMPSTRING *fname = NULL;
191    ASN1_OCTET_STRING *lkid = NULL;
192
193    if ((attrib = PKCS12_SAFEBAG_get0_attr(bag, NID_friendlyName)))
194        fname = attrib->value.bmpstring;
195
196    if ((attrib = PKCS12_SAFEBAG_get0_attr(bag, NID_localKeyID)))
197        lkid = attrib->value.octet_string;
198
199    switch (PKCS12_SAFEBAG_get_nid(bag)) {
200    case NID_keyBag:
201        if (pkey == NULL || *pkey != NULL)
202            return 1;
203        *pkey = EVP_PKCS82PKEY(PKCS12_SAFEBAG_get0_p8inf(bag));
204        if (*pkey == NULL)
205            return 0;
206        break;
207
208    case NID_pkcs8ShroudedKeyBag:
209        if (pkey == NULL || *pkey != NULL)
210            return 1;
211        if ((p8 = PKCS12_decrypt_skey(bag, pass, passlen)) == NULL)
212            return 0;
213        *pkey = EVP_PKCS82PKEY(p8);
214        PKCS8_PRIV_KEY_INFO_free(p8);
215        if (!(*pkey))
216            return 0;
217        break;
218
219    case NID_certBag:
220        if (ocerts == NULL
221                || PKCS12_SAFEBAG_get_bag_nid(bag) != NID_x509Certificate)
222            return 1;
223        if ((x509 = PKCS12_SAFEBAG_get1_cert(bag)) == NULL)
224            return 0;
225        if (lkid && !X509_keyid_set1(x509, lkid->data, lkid->length)) {
226            X509_free(x509);
227            return 0;
228        }
229        if (fname) {
230            int len, r;
231            unsigned char *data;
232
233            len = ASN1_STRING_to_UTF8(&data, fname);
234            if (len >= 0) {
235                r = X509_alias_set1(x509, data, len);
236                OPENSSL_free(data);
237                if (!r) {
238                    X509_free(x509);
239                    return 0;
240                }
241            }
242        }
243
244        if (!sk_X509_push(ocerts, x509)) {
245            X509_free(x509);
246            return 0;
247        }
248
249        break;
250
251    case NID_safeContentsBag:
252        return parse_bags(PKCS12_SAFEBAG_get0_safes(bag), pass, passlen, pkey,
253                          ocerts);
254
255    default:
256        return 1;
257    }
258    return 1;
259}
260