openssl/apps/enc.c
Richard Levitte b646179229 Copyright year updates
Reviewed-by: Neil Horman <nhorman@openssl.org>
Release: yes
(cherry picked from commit 0ce7d1f355)

Reviewed-by: Hugo Landau <hlandau@openssl.org>
Reviewed-by: Tomas Mraz <tomas@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/24034)
2024-04-09 13:43:26 +02:00

789 lines
24 KiB
C

/*
* Copyright 1995-2024 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
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <limits.h>
#include "apps.h"
#include "progs.h"
#include <openssl/bio.h>
#include <openssl/err.h>
#include <openssl/evp.h>
#include <openssl/objects.h>
#include <openssl/x509.h>
#include <openssl/rand.h>
#include <openssl/pem.h>
#ifndef OPENSSL_NO_COMP
# include <openssl/comp.h>
#endif
#include <ctype.h>
#undef SIZE
#undef BSIZE
#define SIZE (512)
#define BSIZE (8*1024)
#define PBKDF2_ITER_DEFAULT 10000
#define STR(a) XSTR(a)
#define XSTR(a) #a
static int set_hex(const char *in, unsigned char *out, int size);
static void show_ciphers(const OBJ_NAME *name, void *bio_);
struct doall_enc_ciphers {
BIO *bio;
int n;
};
typedef enum OPTION_choice {
OPT_COMMON,
OPT_LIST,
OPT_E, OPT_IN, OPT_OUT, OPT_PASS, OPT_ENGINE, OPT_D, OPT_P, OPT_V,
OPT_NOPAD, OPT_SALT, OPT_NOSALT, OPT_DEBUG, OPT_UPPER_P, OPT_UPPER_A,
OPT_A, OPT_Z, OPT_BUFSIZE, OPT_K, OPT_KFILE, OPT_UPPER_K, OPT_NONE,
OPT_UPPER_S, OPT_IV, OPT_MD, OPT_ITER, OPT_PBKDF2, OPT_CIPHER,
OPT_SALTLEN, OPT_R_ENUM, OPT_PROV_ENUM
} OPTION_CHOICE;
const OPTIONS enc_options[] = {
OPT_SECTION("General"),
{"help", OPT_HELP, '-', "Display this summary"},
{"list", OPT_LIST, '-', "List ciphers"},
#ifndef OPENSSL_NO_DEPRECATED_3_0
{"ciphers", OPT_LIST, '-', "Alias for -list"},
#endif
{"e", OPT_E, '-', "Encrypt"},
{"d", OPT_D, '-', "Decrypt"},
{"p", OPT_P, '-', "Print the iv/key"},
{"P", OPT_UPPER_P, '-', "Print the iv/key and exit"},
#ifndef OPENSSL_NO_ENGINE
{"engine", OPT_ENGINE, 's', "Use engine, possibly a hardware device"},
#endif
OPT_SECTION("Input"),
{"in", OPT_IN, '<', "Input file"},
{"k", OPT_K, 's', "Passphrase"},
{"kfile", OPT_KFILE, '<', "Read passphrase from file"},
OPT_SECTION("Output"),
{"out", OPT_OUT, '>', "Output file"},
{"pass", OPT_PASS, 's', "Passphrase source"},
{"v", OPT_V, '-', "Verbose output"},
{"a", OPT_A, '-', "Base64 encode/decode, depending on encryption flag"},
{"base64", OPT_A, '-', "Same as option -a"},
{"A", OPT_UPPER_A, '-',
"Used with -[base64|a] to specify base64 buffer as a single line"},
OPT_SECTION("Encryption"),
{"nopad", OPT_NOPAD, '-', "Disable standard block padding"},
{"salt", OPT_SALT, '-', "Use salt in the KDF (default)"},
{"nosalt", OPT_NOSALT, '-', "Do not use salt in the KDF"},
{"debug", OPT_DEBUG, '-', "Print debug info"},
{"bufsize", OPT_BUFSIZE, 's', "Buffer size"},
{"K", OPT_UPPER_K, 's', "Raw key, in hex"},
{"S", OPT_UPPER_S, 's', "Salt, in hex"},
{"iv", OPT_IV, 's', "IV in hex"},
{"md", OPT_MD, 's', "Use specified digest to create a key from the passphrase"},
{"iter", OPT_ITER, 'p',
"Specify the iteration count and force the use of PBKDF2"},
{OPT_MORE_STR, 0, 0, "Default: " STR(PBKDF2_ITER_DEFAULT)},
{"pbkdf2", OPT_PBKDF2, '-',
"Use password-based key derivation function 2 (PBKDF2)"},
{OPT_MORE_STR, 0, 0,
"Use -iter to change the iteration count from " STR(PBKDF2_ITER_DEFAULT)},
{"none", OPT_NONE, '-', "Don't encrypt"},
{"saltlen", OPT_SALTLEN, 'p', "Specify the PBKDF2 salt length (in bytes)"},
{OPT_MORE_STR, 0, 0, "Default: 16"},
#ifndef OPENSSL_NO_ZLIB
{"z", OPT_Z, '-', "Compress or decompress encrypted data using zlib"},
#endif
{"", OPT_CIPHER, '-', "Any supported cipher"},
OPT_R_OPTIONS,
OPT_PROV_OPTIONS,
{NULL}
};
int enc_main(int argc, char **argv)
{
static char buf[128];
static const char magic[] = "Salted__";
ENGINE *e = NULL;
BIO *in = NULL, *out = NULL, *b64 = NULL, *benc = NULL, *rbio =
NULL, *wbio = NULL;
EVP_CIPHER_CTX *ctx = NULL;
EVP_CIPHER *cipher = NULL;
EVP_MD *dgst = NULL;
const char *digestname = NULL;
char *hkey = NULL, *hiv = NULL, *hsalt = NULL, *p;
char *infile = NULL, *outfile = NULL, *prog;
char *str = NULL, *passarg = NULL, *pass = NULL, *strbuf = NULL;
const char *ciphername = NULL;
char mbuf[sizeof(magic) - 1];
OPTION_CHOICE o;
int bsize = BSIZE, verbose = 0, debug = 0, olb64 = 0, nosalt = 0;
int enc = 1, printkey = 0, i, k;
int base64 = 0, informat = FORMAT_BINARY, outformat = FORMAT_BINARY;
int ret = 1, inl, nopad = 0;
unsigned char key[EVP_MAX_KEY_LENGTH], iv[EVP_MAX_IV_LENGTH];
unsigned char *buff = NULL, salt[EVP_MAX_IV_LENGTH];
int saltlen = 0;
int pbkdf2 = 0;
int iter = 0;
long n;
int streamable = 1;
int wrap = 0;
struct doall_enc_ciphers dec;
#ifndef OPENSSL_NO_ZLIB
int do_zlib = 0;
BIO *bzl = NULL;
#endif
int do_brotli = 0;
BIO *bbrot = NULL;
int do_zstd = 0;
BIO *bzstd = NULL;
/* first check the command name */
if (strcmp(argv[0], "base64") == 0)
base64 = 1;
#ifndef OPENSSL_NO_ZLIB
else if (strcmp(argv[0], "zlib") == 0)
do_zlib = 1;
#endif
#ifndef OPENSSL_NO_BROTLI
else if (strcmp(argv[0], "brotli") == 0)
do_brotli = 1;
#endif
#ifndef OPENSSL_NO_ZSTD
else if (strcmp(argv[0], "zstd") == 0)
do_zstd = 1;
#endif
else if (strcmp(argv[0], "enc") != 0)
ciphername = argv[0];
opt_set_unknown_name("cipher");
prog = opt_init(argc, argv, enc_options);
while ((o = opt_next()) != OPT_EOF) {
switch (o) {
case OPT_EOF:
case OPT_ERR:
opthelp:
BIO_printf(bio_err, "%s: Use -help for summary.\n", prog);
goto end;
case OPT_HELP:
opt_help(enc_options);
ret = 0;
goto end;
case OPT_LIST:
BIO_printf(bio_out, "Supported ciphers:\n");
dec.bio = bio_out;
dec.n = 0;
OBJ_NAME_do_all_sorted(OBJ_NAME_TYPE_CIPHER_METH,
show_ciphers, &dec);
BIO_printf(bio_out, "\n");
ret = 0;
goto end;
case OPT_E:
enc = 1;
break;
case OPT_IN:
infile = opt_arg();
break;
case OPT_OUT:
outfile = opt_arg();
break;
case OPT_PASS:
passarg = opt_arg();
break;
case OPT_ENGINE:
e = setup_engine(opt_arg(), 0);
break;
case OPT_D:
enc = 0;
break;
case OPT_P:
printkey = 1;
break;
case OPT_V:
verbose = 1;
break;
case OPT_NOPAD:
nopad = 1;
break;
case OPT_SALT:
nosalt = 0;
break;
case OPT_NOSALT:
nosalt = 1;
break;
case OPT_DEBUG:
debug = 1;
break;
case OPT_UPPER_P:
printkey = 2;
break;
case OPT_UPPER_A:
olb64 = 1;
break;
case OPT_A:
base64 = 1;
break;
case OPT_Z:
#ifndef OPENSSL_NO_ZLIB
do_zlib = 1;
#endif
break;
case OPT_BUFSIZE:
p = opt_arg();
i = (int)strlen(p) - 1;
k = i >= 1 && p[i] == 'k';
if (k)
p[i] = '\0';
if (!opt_long(opt_arg(), &n)
|| n < 0 || (k && n >= LONG_MAX / 1024))
goto opthelp;
if (k)
n *= 1024;
bsize = (int)n;
break;
case OPT_K:
str = opt_arg();
break;
case OPT_KFILE:
in = bio_open_default(opt_arg(), 'r', FORMAT_TEXT);
if (in == NULL)
goto opthelp;
i = BIO_gets(in, buf, sizeof(buf));
BIO_free(in);
in = NULL;
if (i <= 0) {
BIO_printf(bio_err,
"%s Can't read key from %s\n", prog, opt_arg());
goto opthelp;
}
while (--i > 0 && (buf[i] == '\r' || buf[i] == '\n'))
buf[i] = '\0';
if (i <= 0) {
BIO_printf(bio_err, "%s: zero length password\n", prog);
goto opthelp;
}
str = buf;
break;
case OPT_UPPER_K:
hkey = opt_arg();
break;
case OPT_UPPER_S:
hsalt = opt_arg();
break;
case OPT_IV:
hiv = opt_arg();
break;
case OPT_MD:
digestname = opt_arg();
break;
case OPT_CIPHER:
ciphername = opt_unknown();
break;
case OPT_ITER:
iter = opt_int_arg();
pbkdf2 = 1;
break;
case OPT_SALTLEN:
if (!opt_int(opt_arg(), &saltlen))
goto opthelp;
if (saltlen > (int)sizeof(salt))
saltlen = (int)sizeof(salt);
break;
case OPT_PBKDF2:
pbkdf2 = 1;
if (iter == 0) /* do not overwrite a chosen value */
iter = PBKDF2_ITER_DEFAULT;
break;
case OPT_NONE:
cipher = NULL;
break;
case OPT_R_CASES:
if (!opt_rand(o))
goto end;
break;
case OPT_PROV_CASES:
if (!opt_provider(o))
goto end;
break;
}
}
/* No extra arguments. */
if (!opt_check_rest_arg(NULL))
goto opthelp;
if (!app_RAND_load())
goto end;
if (saltlen == 0 || pbkdf2 == 0)
saltlen = PKCS5_SALT_LEN;
/* Get the cipher name, either from progname (if set) or flag. */
if (!opt_cipher(ciphername, &cipher))
goto opthelp;
if (cipher && (EVP_CIPHER_mode(cipher) == EVP_CIPH_WRAP_MODE)) {
wrap = 1;
streamable = 0;
}
if (digestname != NULL) {
if (!opt_md(digestname, &dgst))
goto opthelp;
}
if (dgst == NULL)
dgst = (EVP_MD *)EVP_sha256();
if (iter == 0)
iter = 1;
/* It must be large enough for a base64 encoded line */
if (base64 && bsize < 80)
bsize = 80;
if (verbose)
BIO_printf(bio_err, "bufsize=%d\n", bsize);
#ifndef OPENSSL_NO_ZLIB
if (do_zlib)
base64 = 0;
#endif
if (do_brotli)
base64 = 0;
if (do_zstd)
base64 = 0;
if (base64) {
if (enc)
outformat = FORMAT_BASE64;
else
informat = FORMAT_BASE64;
}
strbuf = app_malloc(SIZE, "strbuf");
buff = app_malloc(EVP_ENCODE_LENGTH(bsize), "evp buffer");
if (infile == NULL) {
if (!streamable && printkey != 2) { /* if just print key and exit, it's ok */
BIO_printf(bio_err, "Unstreamable cipher mode\n");
goto end;
}
in = dup_bio_in(informat);
} else {
in = bio_open_default(infile, 'r', informat);
}
if (in == NULL)
goto end;
if (str == NULL && passarg != NULL) {
if (!app_passwd(passarg, NULL, &pass, NULL)) {
BIO_printf(bio_err, "Error getting password\n");
goto end;
}
str = pass;
}
if ((str == NULL) && (cipher != NULL) && (hkey == NULL)) {
if (1) {
#ifndef OPENSSL_NO_UI_CONSOLE
for (;;) {
char prompt[200];
BIO_snprintf(prompt, sizeof(prompt), "enter %s %s password:",
EVP_CIPHER_get0_name(cipher),
(enc) ? "encryption" : "decryption");
strbuf[0] = '\0';
i = EVP_read_pw_string((char *)strbuf, SIZE, prompt, enc);
if (i == 0) {
if (strbuf[0] == '\0') {
ret = 1;
goto end;
}
str = strbuf;
break;
}
if (i < 0) {
BIO_printf(bio_err, "bad password read\n");
goto end;
}
}
} else {
#endif
BIO_printf(bio_err, "password required\n");
goto end;
}
}
out = bio_open_default(outfile, 'w', outformat);
if (out == NULL)
goto end;
if (debug) {
BIO_set_callback_ex(in, BIO_debug_callback_ex);
BIO_set_callback_ex(out, BIO_debug_callback_ex);
BIO_set_callback_arg(in, (char *)bio_err);
BIO_set_callback_arg(out, (char *)bio_err);
}
rbio = in;
wbio = out;
#ifndef OPENSSL_NO_COMP
# ifndef OPENSSL_NO_ZLIB
if (do_zlib) {
if ((bzl = BIO_new(BIO_f_zlib())) == NULL)
goto end;
if (debug) {
BIO_set_callback_ex(bzl, BIO_debug_callback_ex);
BIO_set_callback_arg(bzl, (char *)bio_err);
}
if (enc)
wbio = BIO_push(bzl, wbio);
else
rbio = BIO_push(bzl, rbio);
}
# endif
if (do_brotli) {
if ((bbrot = BIO_new(BIO_f_brotli())) == NULL)
goto end;
if (debug) {
BIO_set_callback_ex(bbrot, BIO_debug_callback_ex);
BIO_set_callback_arg(bbrot, (char *)bio_err);
}
if (enc)
wbio = BIO_push(bbrot, wbio);
else
rbio = BIO_push(bbrot, rbio);
}
if (do_zstd) {
if ((bzstd = BIO_new(BIO_f_zstd())) == NULL)
goto end;
if (debug) {
BIO_set_callback_ex(bzstd, BIO_debug_callback_ex);
BIO_set_callback_arg(bzstd, (char *)bio_err);
}
if (enc)
wbio = BIO_push(bzstd, wbio);
else
rbio = BIO_push(bzstd, rbio);
}
#endif
if (base64) {
if ((b64 = BIO_new(BIO_f_base64())) == NULL)
goto end;
if (debug) {
BIO_set_callback_ex(b64, BIO_debug_callback_ex);
BIO_set_callback_arg(b64, (char *)bio_err);
}
if (olb64)
BIO_set_flags(b64, BIO_FLAGS_BASE64_NO_NL);
if (enc)
wbio = BIO_push(b64, wbio);
else
rbio = BIO_push(b64, rbio);
}
if (cipher != NULL) {
if (str != NULL) { /* a passphrase is available */
/*
* Salt handling: if encrypting generate a salt if not supplied,
* and write to output BIO. If decrypting use salt from input BIO
* if not given with args
*/
unsigned char *sptr;
size_t str_len = strlen(str);
if (nosalt) {
sptr = NULL;
} else {
if (hsalt != NULL && !set_hex(hsalt, salt, saltlen)) {
BIO_printf(bio_err, "invalid hex salt value\n");
goto end;
}
if (enc) { /* encryption */
if (hsalt == NULL) {
if (RAND_bytes(salt, saltlen) <= 0) {
BIO_printf(bio_err, "RAND_bytes failed\n");
goto end;
}
/*
* If -P option then don't bother writing.
* If salt is given, shouldn't either ?
*/
if ((printkey != 2)
&& (BIO_write(wbio, magic,
sizeof(magic) - 1) != sizeof(magic) - 1
|| BIO_write(wbio,
(char *)salt,
saltlen) != saltlen)) {
BIO_printf(bio_err, "error writing output file\n");
goto end;
}
}
} else { /* decryption */
if (hsalt == NULL) {
if (BIO_read(rbio, mbuf, sizeof(mbuf)) != sizeof(mbuf)) {
BIO_printf(bio_err, "error reading input file\n");
goto end;
}
if (memcmp(mbuf, magic, sizeof(mbuf)) == 0) { /* file IS salted */
if (BIO_read(rbio, salt,
saltlen) != saltlen) {
BIO_printf(bio_err, "error reading input file\n");
goto end;
}
} else { /* file is NOT salted, NO salt available */
BIO_printf(bio_err, "bad magic number\n");
goto end;
}
}
}
sptr = salt;
}
if (pbkdf2 == 1) {
/*
* derive key and default iv
* concatenated into a temporary buffer
*/
unsigned char tmpkeyiv[EVP_MAX_KEY_LENGTH + EVP_MAX_IV_LENGTH];
int iklen = EVP_CIPHER_get_key_length(cipher);
int ivlen = EVP_CIPHER_get_iv_length(cipher);
/* not needed if HASH_UPDATE() is fixed : */
int islen = (sptr != NULL ? saltlen : 0);
if (!PKCS5_PBKDF2_HMAC(str, str_len, sptr, islen,
iter, dgst, iklen+ivlen, tmpkeyiv)) {
BIO_printf(bio_err, "PKCS5_PBKDF2_HMAC failed\n");
goto end;
}
/* split and move data back to global buffer */
memcpy(key, tmpkeyiv, iklen);
memcpy(iv, tmpkeyiv+iklen, ivlen);
} else {
BIO_printf(bio_err, "*** WARNING : "
"deprecated key derivation used.\n"
"Using -iter or -pbkdf2 would be better.\n");
if (!EVP_BytesToKey(cipher, dgst, sptr,
(unsigned char *)str, str_len,
1, key, iv)) {
BIO_printf(bio_err, "EVP_BytesToKey failed\n");
goto end;
}
}
/*
* zero the complete buffer or the string passed from the command
* line.
*/
if (str == strbuf)
OPENSSL_cleanse(str, SIZE);
else
OPENSSL_cleanse(str, str_len);
}
if (hiv != NULL) {
int siz = EVP_CIPHER_get_iv_length(cipher);
if (siz == 0) {
BIO_printf(bio_err, "warning: iv not used by this cipher\n");
} else if (!set_hex(hiv, iv, siz)) {
BIO_printf(bio_err, "invalid hex iv value\n");
goto end;
}
}
if ((hiv == NULL) && (str == NULL)
&& EVP_CIPHER_get_iv_length(cipher) != 0
&& wrap == 0) {
/*
* No IV was explicitly set and no IV was generated.
* Hence the IV is undefined, making correct decryption impossible.
*/
BIO_printf(bio_err, "iv undefined\n");
goto end;
}
if (hkey != NULL) {
if (!set_hex(hkey, key, EVP_CIPHER_get_key_length(cipher))) {
BIO_printf(bio_err, "invalid hex key value\n");
goto end;
}
/* wiping secret data as we no longer need it */
cleanse(hkey);
}
if ((benc = BIO_new(BIO_f_cipher())) == NULL)
goto end;
/*
* Since we may be changing parameters work on the encryption context
* rather than calling BIO_set_cipher().
*/
BIO_get_cipher_ctx(benc, &ctx);
if (wrap == 1)
EVP_CIPHER_CTX_set_flags(ctx, EVP_CIPHER_CTX_FLAG_WRAP_ALLOW);
if (!EVP_CipherInit_ex(ctx, cipher, e, NULL, NULL, enc)) {
BIO_printf(bio_err, "Error setting cipher %s\n",
EVP_CIPHER_get0_name(cipher));
ERR_print_errors(bio_err);
goto end;
}
if (nopad)
EVP_CIPHER_CTX_set_padding(ctx, 0);
if (!EVP_CipherInit_ex(ctx, NULL, NULL, key,
(hiv == NULL && wrap == 1 ? NULL : iv), enc)) {
BIO_printf(bio_err, "Error setting cipher %s\n",
EVP_CIPHER_get0_name(cipher));
ERR_print_errors(bio_err);
goto end;
}
if (debug) {
BIO_set_callback_ex(benc, BIO_debug_callback_ex);
BIO_set_callback_arg(benc, (char *)bio_err);
}
if (printkey) {
if (!nosalt) {
printf("salt=");
for (i = 0; i < (int)saltlen; i++)
printf("%02X", salt[i]);
printf("\n");
}
if (EVP_CIPHER_get_key_length(cipher) > 0) {
printf("key=");
for (i = 0; i < EVP_CIPHER_get_key_length(cipher); i++)
printf("%02X", key[i]);
printf("\n");
}
if (EVP_CIPHER_get_iv_length(cipher) > 0) {
printf("iv =");
for (i = 0; i < EVP_CIPHER_get_iv_length(cipher); i++)
printf("%02X", iv[i]);
printf("\n");
}
if (printkey == 2) {
ret = 0;
goto end;
}
}
}
/* Only encrypt/decrypt as we write the file */
if (benc != NULL)
wbio = BIO_push(benc, wbio);
while (BIO_pending(rbio) || !BIO_eof(rbio)) {
inl = BIO_read(rbio, (char *)buff, bsize);
if (inl <= 0)
break;
if (!streamable && !BIO_eof(rbio)) { /* do not output data */
BIO_printf(bio_err, "Unstreamable cipher mode\n");
goto end;
}
if (BIO_write(wbio, (char *)buff, inl) != inl) {
BIO_printf(bio_err, "error writing output file\n");
goto end;
}
if (!streamable)
break;
}
if (!BIO_flush(wbio)) {
if (enc)
BIO_printf(bio_err, "bad encrypt\n");
else
BIO_printf(bio_err, "bad decrypt\n");
goto end;
}
ret = 0;
if (verbose) {
BIO_printf(bio_err, "bytes read : %8ju\n", BIO_number_read(in));
BIO_printf(bio_err, "bytes written: %8ju\n", BIO_number_written(out));
}
end:
ERR_print_errors(bio_err);
OPENSSL_free(strbuf);
OPENSSL_free(buff);
BIO_free(in);
BIO_free_all(out);
BIO_free(benc);
BIO_free(b64);
EVP_MD_free(dgst);
EVP_CIPHER_free(cipher);
#ifndef OPENSSL_NO_ZLIB
BIO_free(bzl);
#endif
BIO_free(bbrot);
BIO_free(bzstd);
release_engine(e);
OPENSSL_free(pass);
return ret;
}
static void show_ciphers(const OBJ_NAME *name, void *arg)
{
struct doall_enc_ciphers *dec = (struct doall_enc_ciphers *)arg;
const EVP_CIPHER *cipher;
if (!islower((unsigned char)*name->name))
return;
/* Filter out ciphers that we cannot use */
cipher = EVP_get_cipherbyname(name->name);
if (cipher == NULL
|| (EVP_CIPHER_get_flags(cipher) & EVP_CIPH_FLAG_AEAD_CIPHER) != 0
|| EVP_CIPHER_get_mode(cipher) == EVP_CIPH_XTS_MODE)
return;
BIO_printf(dec->bio, "-%-25s", name->name);
if (++dec->n == 3) {
BIO_printf(dec->bio, "\n");
dec->n = 0;
} else
BIO_printf(dec->bio, " ");
}
static int set_hex(const char *in, unsigned char *out, int size)
{
int i, n;
unsigned char j;
i = size * 2;
n = strlen(in);
if (n > i) {
BIO_printf(bio_err, "hex string is too long, ignoring excess\n");
n = i; /* ignore exceeding part */
} else if (n < i) {
BIO_printf(bio_err, "hex string is too short, padding with zero bytes to length\n");
}
memset(out, 0, size);
for (i = 0; i < n; i++) {
j = (unsigned char)*in++;
if (!isxdigit(j)) {
BIO_printf(bio_err, "non-hex digit\n");
return 0;
}
j = (unsigned char)OPENSSL_hexchar2int(j);
if (i & 1)
out[i / 2] |= j;
else
out[i / 2] = (j << 4);
}
return 1;
}