crypto/passphrase.c

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