qemu

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/*
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 * QEMU base64 helpers
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 *
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 * Copyright (c) 2015 Red Hat, Inc.
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 *
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 * This library is free software; you can redistribute it and/or
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 * modify it under the terms of the GNU Lesser General Public
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 * License as published by the Free Software Foundation; either
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 * version 2.1 of the License, or (at your option) any later version.
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 *
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 * This library is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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 * Lesser General Public License for more details.
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 *
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 * You should have received a copy of the GNU Lesser General Public
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 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
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 *
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 */
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#include "qemu/osdep.h"
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#include "qapi/error.h"
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#include "qemu/base64.h"
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static const char *base64_valid_chars =
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    "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=\n";
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uint8_t *qbase64_decode(const char *input,
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                        size_t in_len,
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                        size_t *out_len,
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                        Error **errp)
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{
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    *out_len = 0;
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    if (in_len != -1) {
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        /* Lack of NUL terminator is an error */
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        if (input[in_len] != '\0') {
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            error_setg(errp, "Base64 data is not NUL terminated");
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            return NULL;
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        }
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        /* Check there's no NULs embedded since we expect
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         * this to be valid base64 data */
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        if (memchr(input, '\0', in_len) != NULL) {
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            error_setg(errp, "Base64 data contains embedded NUL characters");
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            return NULL;
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        }
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        /* Now we know its a valid nul terminated string
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         * strspn is safe to use... */
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    } else {
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        in_len = strlen(input);
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    }
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    if (strspn(input, base64_valid_chars) != in_len) {
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        error_setg(errp, "Base64 data contains invalid characters");
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        return NULL;
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    }
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    return g_base64_decode(input, out_len);
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}
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