xref: /freebsd/crypto/openssl/crypto/passphrase.c (revision b077aed33b7b6aefca7b17ddb250cf521f938613)
1 /*
2  * Copyright 2020-2022 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/err.h>
11 #include <openssl/ui.h>
12 #include <openssl/core_names.h>
13 #include "internal/cryptlib.h"
14 #include "internal/passphrase.h"
15 
ossl_pw_clear_passphrase_data(struct ossl_passphrase_data_st * data)16 void ossl_pw_clear_passphrase_data(struct ossl_passphrase_data_st *data)
17 {
18     if (data != NULL) {
19         if (data->type == is_expl_passphrase)
20             OPENSSL_clear_free(data->_.expl_passphrase.passphrase_copy,
21                                data->_.expl_passphrase.passphrase_len);
22         ossl_pw_clear_passphrase_cache(data);
23         memset(data, 0, sizeof(*data));
24     }
25 }
26 
ossl_pw_clear_passphrase_cache(struct ossl_passphrase_data_st * data)27 void ossl_pw_clear_passphrase_cache(struct ossl_passphrase_data_st *data)
28 {
29     OPENSSL_clear_free(data->cached_passphrase, data->cached_passphrase_len);
30     data->cached_passphrase = NULL;
31 }
32 
ossl_pw_set_passphrase(struct ossl_passphrase_data_st * data,const unsigned char * passphrase,size_t passphrase_len)33 int ossl_pw_set_passphrase(struct ossl_passphrase_data_st *data,
34                            const unsigned char *passphrase,
35                            size_t passphrase_len)
36 {
37     if (!ossl_assert(data != NULL && passphrase != NULL)) {
38         ERR_raise(ERR_LIB_CRYPTO, ERR_R_PASSED_NULL_PARAMETER);
39         return 0;
40     }
41     ossl_pw_clear_passphrase_data(data);
42     data->type = is_expl_passphrase;
43     data->_.expl_passphrase.passphrase_copy =
44         passphrase_len != 0 ? OPENSSL_memdup(passphrase, passphrase_len)
45                             : OPENSSL_malloc(1);
46     if (data->_.expl_passphrase.passphrase_copy == NULL) {
47         ERR_raise(ERR_LIB_CRYPTO, ERR_R_MALLOC_FAILURE);
48         return 0;
49     }
50     data->_.expl_passphrase.passphrase_len = passphrase_len;
51     return 1;
52 }
53 
ossl_pw_set_pem_password_cb(struct ossl_passphrase_data_st * data,pem_password_cb * cb,void * cbarg)54 int ossl_pw_set_pem_password_cb(struct ossl_passphrase_data_st *data,
55                                 pem_password_cb *cb, void *cbarg)
56 {
57     if (!ossl_assert(data != NULL && cb != NULL)) {
58         ERR_raise(ERR_LIB_CRYPTO, ERR_R_PASSED_NULL_PARAMETER);
59         return 0;
60     }
61     ossl_pw_clear_passphrase_data(data);
62     data->type = is_pem_password;
63     data->_.pem_password.password_cb = cb;
64     data->_.pem_password.password_cbarg = cbarg;
65     return 1;
66 }
67 
ossl_pw_set_ossl_passphrase_cb(struct ossl_passphrase_data_st * data,OSSL_PASSPHRASE_CALLBACK * cb,void * cbarg)68 int ossl_pw_set_ossl_passphrase_cb(struct ossl_passphrase_data_st *data,
69                                    OSSL_PASSPHRASE_CALLBACK *cb, void *cbarg)
70 {
71     if (!ossl_assert(data != NULL && cb != NULL)) {
72         ERR_raise(ERR_LIB_CRYPTO, ERR_R_PASSED_NULL_PARAMETER);
73         return 0;
74     }
75     ossl_pw_clear_passphrase_data(data);
76     data->type = is_ossl_passphrase;
77     data->_.ossl_passphrase.passphrase_cb = cb;
78     data->_.ossl_passphrase.passphrase_cbarg = cbarg;
79     return 1;
80 }
81 
ossl_pw_set_ui_method(struct ossl_passphrase_data_st * data,const UI_METHOD * ui_method,void * ui_data)82 int ossl_pw_set_ui_method(struct ossl_passphrase_data_st *data,
83                           const UI_METHOD *ui_method, void *ui_data)
84 {
85     if (!ossl_assert(data != NULL && ui_method != NULL)) {
86         ERR_raise(ERR_LIB_CRYPTO, ERR_R_PASSED_NULL_PARAMETER);
87         return 0;
88     }
89     ossl_pw_clear_passphrase_data(data);
90     data->type = is_ui_method;
91     data->_.ui_method.ui_method = ui_method;
92     data->_.ui_method.ui_method_data = ui_data;
93     return 1;
94 }
95 
ossl_pw_enable_passphrase_caching(struct ossl_passphrase_data_st * data)96 int ossl_pw_enable_passphrase_caching(struct ossl_passphrase_data_st *data)
97 {
98     data->flag_cache_passphrase = 1;
99     return 1;
100 }
101 
ossl_pw_disable_passphrase_caching(struct ossl_passphrase_data_st * data)102 int ossl_pw_disable_passphrase_caching(struct ossl_passphrase_data_st *data)
103 {
104     data->flag_cache_passphrase = 0;
105     return 1;
106 }
107 
108 
109 /*-
110  * UI_METHOD processor.  It differs from UI_UTIL_read_pw() like this:
111  *
112  * 1.  It constructs a prompt on its own, based on |prompt_info|.
113  * 2.  It allocates a buffer for password and verification on its own
114  *     to compensate for NUL terminator in UI password strings.
115  * 3.  It raises errors.
116  * 4.  It reports back the length of the prompted pass phrase.
117  */
do_ui_passphrase(char * pass,size_t pass_size,size_t * pass_len,const char * prompt_info,int verify,const UI_METHOD * ui_method,void * ui_data)118 static int do_ui_passphrase(char *pass, size_t pass_size, size_t *pass_len,
119                             const char *prompt_info, int verify,
120                             const UI_METHOD *ui_method, void *ui_data)
121 {
122     char *prompt = NULL, *ipass = NULL, *vpass = NULL;
123     int prompt_idx = -1, verify_idx = -1, res;
124     UI *ui = NULL;
125     int ret = 0;
126 
127     if (!ossl_assert(pass != NULL && pass_size != 0 && pass_len != NULL)) {
128         ERR_raise(ERR_LIB_CRYPTO, ERR_R_PASSED_NULL_PARAMETER);
129         return 0;
130     }
131 
132     if ((ui = UI_new()) == NULL) {
133         ERR_raise(ERR_LIB_CRYPTO, ERR_R_MALLOC_FAILURE);
134         return 0;
135     }
136 
137     if (ui_method != NULL) {
138         UI_set_method(ui, ui_method);
139         if (ui_data != NULL)
140             UI_add_user_data(ui, ui_data);
141     }
142 
143     /* Get an application constructed prompt */
144     prompt = UI_construct_prompt(ui, "pass phrase", prompt_info);
145     if (prompt == NULL) {
146         ERR_raise(ERR_LIB_CRYPTO, ERR_R_MALLOC_FAILURE);
147         goto end;
148     }
149 
150     /* Get a buffer for verification prompt */
151     ipass = OPENSSL_zalloc(pass_size + 1);
152     if (ipass == NULL) {
153         ERR_raise(ERR_LIB_CRYPTO, ERR_R_MALLOC_FAILURE);
154         goto end;
155     }
156 
157     prompt_idx = UI_add_input_string(ui, prompt,
158                                      UI_INPUT_FLAG_DEFAULT_PWD,
159                                      ipass, 0, pass_size) - 1;
160     if (prompt_idx < 0) {
161         ERR_raise(ERR_LIB_CRYPTO, ERR_R_UI_LIB);
162         goto end;
163     }
164 
165     if (verify) {
166         /* Get a buffer for verification prompt */
167         vpass = OPENSSL_zalloc(pass_size + 1);
168         if (vpass == NULL) {
169             ERR_raise(ERR_LIB_CRYPTO, ERR_R_MALLOC_FAILURE);
170             goto end;
171         }
172         verify_idx = UI_add_verify_string(ui, prompt,
173                                           UI_INPUT_FLAG_DEFAULT_PWD,
174                                           vpass, 0, pass_size,
175                                           ipass) - 1;
176         if (verify_idx < 0) {
177             ERR_raise(ERR_LIB_CRYPTO, ERR_R_UI_LIB);
178             goto end;
179         }
180     }
181 
182     switch (UI_process(ui)) {
183     case -2:
184         ERR_raise(ERR_LIB_CRYPTO, ERR_R_INTERRUPTED_OR_CANCELLED);
185         break;
186     case -1:
187         ERR_raise(ERR_LIB_CRYPTO, ERR_R_UI_LIB);
188         break;
189     default:
190         res = UI_get_result_length(ui, prompt_idx);
191         if (res < 0) {
192             ERR_raise(ERR_LIB_CRYPTO, ERR_R_UI_LIB);
193             break;
194         }
195         *pass_len = (size_t)res;
196         memcpy(pass, ipass, *pass_len);
197         ret = 1;
198         break;
199     }
200 
201  end:
202     OPENSSL_clear_free(vpass, pass_size + 1);
203     OPENSSL_clear_free(ipass, pass_size + 1);
204     OPENSSL_free(prompt);
205     UI_free(ui);
206     return ret;
207 }
208 
209 /* Central pw prompting dispatcher */
ossl_pw_get_passphrase(char * pass,size_t pass_size,size_t * pass_len,const OSSL_PARAM params[],int verify,struct ossl_passphrase_data_st * data)210 int ossl_pw_get_passphrase(char *pass, size_t pass_size, size_t *pass_len,
211                            const OSSL_PARAM params[], int verify,
212                            struct ossl_passphrase_data_st *data)
213 {
214     const char *source = NULL;
215     size_t source_len = 0;
216     const char *prompt_info = NULL;
217     const UI_METHOD *ui_method = NULL;
218     UI_METHOD *allocated_ui_method = NULL;
219     void *ui_data = NULL;
220     const OSSL_PARAM *p = NULL;
221     int ret;
222 
223     /* Handle explicit and cached passphrases */
224 
225     if (data->type == is_expl_passphrase) {
226         source = data->_.expl_passphrase.passphrase_copy;
227         source_len = data->_.expl_passphrase.passphrase_len;
228     } else if (data->flag_cache_passphrase && data->cached_passphrase != NULL) {
229         source = data->cached_passphrase;
230         source_len = data->cached_passphrase_len;
231     }
232 
233     if (source != NULL) {
234         if (source_len > pass_size)
235             source_len = pass_size;
236         memcpy(pass, source, source_len);
237         *pass_len = source_len;
238         return 1;
239     }
240 
241     /* Handle the is_ossl_passphrase case...  that's pretty direct */
242 
243     if (data->type == is_ossl_passphrase) {
244         OSSL_PASSPHRASE_CALLBACK *cb = data->_.ossl_passphrase.passphrase_cb;
245         void *cbarg = data->_.ossl_passphrase.passphrase_cbarg;
246 
247         ret = cb(pass, pass_size, pass_len, params, cbarg);
248         goto do_cache;
249     }
250 
251     /* Handle the is_pem_password and is_ui_method cases */
252 
253     if ((p = OSSL_PARAM_locate_const(params,
254                                      OSSL_PASSPHRASE_PARAM_INFO)) != NULL) {
255         if (p->data_type != OSSL_PARAM_UTF8_STRING) {
256             ERR_raise_data(ERR_LIB_CRYPTO, ERR_R_PASSED_INVALID_ARGUMENT,
257                            "Prompt info data type incorrect");
258             return 0;
259         }
260         prompt_info = p->data;
261     }
262 
263     if (data->type == is_pem_password) {
264         /* We use a UI wrapper for PEM */
265         pem_password_cb *cb = data->_.pem_password.password_cb;
266 
267         ui_method = allocated_ui_method =
268             UI_UTIL_wrap_read_pem_callback(cb, verify);
269         ui_data = data->_.pem_password.password_cbarg;
270 
271         if (ui_method == NULL) {
272             ERR_raise(ERR_LIB_CRYPTO, ERR_R_MALLOC_FAILURE);
273             return 0;
274         }
275     } else if (data->type == is_ui_method) {
276         ui_method = data->_.ui_method.ui_method;
277         ui_data = data->_.ui_method.ui_method_data;
278     }
279 
280     if (ui_method == NULL) {
281         ERR_raise_data(ERR_LIB_CRYPTO, ERR_R_PASSED_INVALID_ARGUMENT,
282                        "No password method specified");
283         return 0;
284     }
285 
286     ret = do_ui_passphrase(pass, pass_size, pass_len, prompt_info, verify,
287                            ui_method, ui_data);
288 
289     UI_destroy_method(allocated_ui_method);
290 
291  do_cache:
292     if (ret && data->flag_cache_passphrase) {
293         if (data->cached_passphrase == NULL
294             || *pass_len > data->cached_passphrase_len) {
295             void *new_cache =
296                 OPENSSL_clear_realloc(data->cached_passphrase,
297                                       data->cached_passphrase_len,
298                                       *pass_len + 1);
299 
300             if (new_cache == NULL) {
301                 OPENSSL_cleanse(pass, *pass_len);
302                 ERR_raise(ERR_LIB_CRYPTO, ERR_R_MALLOC_FAILURE);
303                 return 0;
304             }
305             data->cached_passphrase = new_cache;
306         }
307         memcpy(data->cached_passphrase, pass, *pass_len);
308         data->cached_passphrase[*pass_len] = '\0';
309         data->cached_passphrase_len = *pass_len;
310     }
311 
312     return ret;
313 }
314 
ossl_pw_get_password(char * buf,int size,int rwflag,void * userdata,const char * info)315 static int ossl_pw_get_password(char *buf, int size, int rwflag,
316                                 void *userdata, const char *info)
317 {
318     size_t password_len = 0;
319     OSSL_PARAM params[] = {
320         OSSL_PARAM_utf8_string(OSSL_PASSPHRASE_PARAM_INFO, NULL, 0),
321         OSSL_PARAM_END
322     };
323 
324     params[0].data = (void *)info;
325     if (ossl_pw_get_passphrase(buf, (size_t)size, &password_len, params,
326                                rwflag, userdata))
327         return (int)password_len;
328     return -1;
329 }
330 
ossl_pw_pem_password(char * buf,int size,int rwflag,void * userdata)331 int ossl_pw_pem_password(char *buf, int size, int rwflag, void *userdata)
332 {
333     return ossl_pw_get_password(buf, size, rwflag, userdata, "PEM");
334 }
335 
ossl_pw_pvk_password(char * buf,int size,int rwflag,void * userdata)336 int ossl_pw_pvk_password(char *buf, int size, int rwflag, void *userdata)
337 {
338     return ossl_pw_get_password(buf, size, rwflag, userdata, "PVK");
339 }
340 
ossl_pw_passphrase_callback_enc(char * pass,size_t pass_size,size_t * pass_len,const OSSL_PARAM params[],void * arg)341 int ossl_pw_passphrase_callback_enc(char *pass, size_t pass_size,
342                                     size_t *pass_len,
343                                     const OSSL_PARAM params[], void *arg)
344 {
345     return ossl_pw_get_passphrase(pass, pass_size, pass_len, params, 1, arg);
346 }
347 
ossl_pw_passphrase_callback_dec(char * pass,size_t pass_size,size_t * pass_len,const OSSL_PARAM params[],void * arg)348 int ossl_pw_passphrase_callback_dec(char *pass, size_t pass_size,
349                                     size_t *pass_len,
350                                     const OSSL_PARAM params[], void *arg)
351 {
352     return ossl_pw_get_passphrase(pass, pass_size, pass_len, params, 0, arg);
353 }
354