DOKK / manpages / debian 10 / libssl-doc / PKCS12_newpass.3ssl.en
PKCS12_NEWPASS(3SSL) OpenSSL PKCS12_NEWPASS(3SSL)

PKCS12_newpass - change the password of a PKCS12 structure

 #include <openssl/pkcs12.h>
 int PKCS12_newpass(PKCS12 *p12, const char *oldpass, const char *newpass);

PKCS12_newpass() changes the password of a PKCS12 structure.

p12 is a pointer to a PKCS12 structure. oldpass is the existing password and newpass is the new password.

Each of oldpass and newpass is independently interpreted as a string in the UTF-8 encoding. If it is not valid UTF-8, it is assumed to be ISO8859-1 instead.

In particular, this means that passwords in the locale character set (or code page on Windows) must potentially be converted to UTF-8 before use. This may include passwords from local text files, or input from the terminal or command line. Refer to the documentation of UI_OpenSSL(3), for example.

PKCS12_newpass() returns 1 on success or 0 on failure. Applications can retrieve the most recent error from PKCS12_newpass() with ERR_get_error().

This example loads a PKCS#12 file, changes its password and writes out the result to a new file.

 #include <stdio.h>
 #include <stdlib.h>
 #include <openssl/pem.h>
 #include <openssl/err.h>
 #include <openssl/pkcs12.h>
 int main(int argc, char **argv)
 {
     FILE *fp;
     PKCS12 *p12;
     if (argc != 5) {
         fprintf(stderr, "Usage: pkread p12file password newpass opfile\n");
         return 1;
     }
     if ((fp = fopen(argv[1], "rb")) == NULL) {
         fprintf(stderr, "Error opening file %s\n", argv[1]);
         return 1;
     }
     p12 = d2i_PKCS12_fp(fp, NULL);
     fclose(fp);
     if (p12 == NULL) {
         fprintf(stderr, "Error reading PKCS#12 file\n");
         ERR_print_errors_fp(stderr);
         return 1;
     }
     if (PKCS12_newpass(p12, argv[2], argv[3]) == 0) {
         fprintf(stderr, "Error changing password\n");
         ERR_print_errors_fp(stderr);
         PKCS12_free(p12);
         return 1;
     }
     if ((fp = fopen(argv[4], "wb")) == NULL) {
         fprintf(stderr, "Error opening file %s\n", argv[4]);
         PKCS12_free(p12);
         return 1;
     }
     i2d_PKCS12_fp(fp, p12);
     PKCS12_free(p12);
     fclose(fp);
     return 0;
 }

If the PKCS#12 structure does not have a password, then you must use the empty string "" for oldpass. Using NULL for oldpass will result in a PKCS12_newpass() failure.

If the wrong password is used for oldpass then the function will fail, with a MAC verification error. In rare cases the PKCS12 structure does not contain a MAC: in this case it will usually fail with a decryption padding error.

The password format is a NULL terminated ASCII string which is converted to Unicode form internally. As a result some passwords cannot be supplied to this function.

PKCS12_create(3), ERR_get_error(3), passphrase-encoding(7)

Copyright 2016-2019 The OpenSSL Project Authors. All Rights Reserved.

Licensed under the OpenSSL license (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>.

2022-06-24 1.1.1n