PKCS12_NEWPASS(3ossl)

📦 version 3.5.0, in opensuse-leap 16.0

🎀 PKCS12_NEWPASS 🎀

ok so this is the 3ossl manpage for PKCS12_newpass and bestie, it does exactly one thing and honestly? it serves 💅

✨ NAME ✨

PKCS12_newpass — change the password of a PKCS12 structure. that's it. that's the whole gig. periodt.

🌸 SYNOPSIS 🌸

#include <openssl/pkcs12.h>

int PKCS12_newpass(PKCS12 *p12, const char *oldpass, const char *newpass);

🦋 DESCRIPTION 🦋

PKCS12_newpass() changes the password of a PKCS12 structure. glow-up for your keystore, basically 💖

So p12 is a pointer to a PKCS12 structure. oldpass is the existing password, and newpass is the new password. simple as.

ok now here's the part where you need to actually pay attention, no cap: 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. both of them, separately, each one, individually. iykyk.

In particular — and this is the bit everyone trips over 🙈 — this means that passwords in the locale character set (or code page on Windows) must potentially be converted to UTF-8 before use. "potentially" doing a lot of work there. 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. like, go read it, it's right there.

🫶 real talk: 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. not in a cute way. in a failure way.

And 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. so like… either way it fails, just with different lore 💀

💜 RETURN VALUES 💜

PKCS12_newpass() returns 1 on success or 0 on failure. iconic binary behaviour, honestly.

Applications can retrieve the most recent error from PKCS12_newpass() with ERR_get_error().

⭐ EXAMPLES ⭐

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

#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;
}

💀 BUGS 💀

ok so this is the unfortunate part, and i'm gonna say it straight:

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. 😭 yeah. some passwords just… can't come to the party. it's giving exclusionary, but it's what we have.

🌈 SEE ALSO 🌈

Copyright 2016-2018 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>.

mwah 💋 that was PKCS12_NEWPASS(3ossl) — version 3.5.0, dated 2026-09-25. stan OpenSSL, hydrate, and convert your passwords to UTF-8 bestie 🎀✨

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