/*

 * Copyright 1995-2026 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

 */

#if defined(__linux) || defined(__sun) || defined(__hpux)

/*

 * Following definition aliases fopen to fopen64 on above mentioned

 * platforms. This makes it possible to open and sequentially access files

 * larger than 2GB from 32-bit application. It does not allow one to traverse

 * them beyond 2GB with fseek/ftell, but on the other hand *no* 32-bit

 * platform permits that, not with fseek/ftell. Not to mention that breaking

 * 2GB limit for seeking would require surgery to *our* API. But sequential

 * access suffices for practical cases when you can run into large files,

 * such as fingerprinting, so we can let API alone. For reference, the list

 * of 32-bit platforms which allow for sequential access of large files

 * without extra "magic" comprise *BSD, Darwin, IRIX...

 */

#ifndef _FILE_OFFSET_BITS

#define _FILE_OFFSET_BITS 64

#endif

#endif

#include <stdio.h>

#include <errno.h>

#include "bio_local.h"

#include <openssl/err.h>

#if !defined(OPENSSL_NO_STDIO)

static int file_write(BIO *h, const char *buf, int num);

static int file_read(BIO *h, char *buf, int size);

static int file_puts(BIO *h, const char *str);

static int file_gets(BIO *h, char *str, int size);

static long file_ctrl(BIO *h, int cmd, long arg1, void *arg2);

static int file_new(BIO *h);

static int file_free(BIO *data);

static const BIO_METHOD methods_filep = {

    BIO_TYPE_FILE,

    "FILE pointer",

    bwrite_conv,

    file_write,

    bread_conv,

    file_read,

    file_puts,

    file_gets,

    file_ctrl,

    file_new,

    file_free,

    NULL, /* file_callback_ctrl */

};

BIO *BIO_new_file(const char *filename, const char *mode)

{

    BIO *ret;

    FILE *file;

    int fp_flags = BIO_CLOSE;

    if (strchr(mode, 'b') == NULL)

        fp_flags |= BIO_FP_TEXT;

    if (filename == NULL) {

        ERR_raise(ERR_LIB_CRYPTO, ERR_R_PASSED_NULL_PARAMETER);

        return NULL;

    }

    file = openssl_fopen(filename, mode);

    if (file == NULL) {

        ERR_raise_data(ERR_LIB_SYS, get_last_sys_error(),

            "calling fopen(%s, %s)",

            filename, mode);

        if (errno == ENOENT

#ifdef ENXIO

            || errno == ENXIO

#endif

        )

            ERR_raise(ERR_LIB_BIO, BIO_R_NO_SUCH_FILE);

        else

            ERR_raise(ERR_LIB_BIO, ERR_R_SYS_LIB);

        return NULL;

    }

    if ((ret = BIO_new(BIO_s_file())) == NULL) {

        fclose(file);

        return NULL;

    }

    /* we did fopen -> we disengage UPLINK */

    BIO_clear_flags(ret, BIO_FLAGS_UPLINK_INTERNAL);

    BIO_set_fp(ret, file, fp_flags);

    return ret;

}

BIO *BIO_new_fp(FILE *stream, int close_flag)

{

    BIO *ret;

    if ((ret = BIO_new(BIO_s_file())) == NULL)

        return NULL;

    /* redundant flag, left for documentation purposes */

    BIO_set_flags(ret, BIO_FLAGS_UPLINK_INTERNAL);

    BIO_set_fp(ret, stream, close_flag);

    return ret;

}

const BIO_METHOD *BIO_s_file(void)

{

    return &methods_filep;

}

static int file_new(BIO *bi)

{

    bi->init = 0;

    bi->num = 0;

    bi->ptr = NULL;

    bi->flags = BIO_FLAGS_UPLINK_INTERNAL; /* default to UPLINK */

    return 1;

}

static int file_free(BIO *a)

{

    if (a == NULL)

        return 0;

    if (a->shutdown) {

        if ((a->init) && (a->ptr != NULL)) {

            if (a->flags & BIO_FLAGS_UPLINK_INTERNAL)

                UP_fclose(a->ptr);

            else

                fclose(a->ptr);

            a->ptr = NULL;

            a->flags = BIO_FLAGS_UPLINK_INTERNAL;

        }

        a->init = 0;

    }

    return 1;

}

static int file_read(BIO *b, char *out, int outl)

{

    int ret = 0;

    if (b->init != 0 && out != NULL && outl > 0) {

        if (b->flags & BIO_FLAGS_UPLINK_INTERNAL)

            ret = (int)UP_fread(out, 1, outl, b->ptr);

        else

            ret = (int)fread(out, 1, outl, (FILE *)b->ptr);

        if (ret == 0

            && (b->flags & BIO_FLAGS_UPLINK_INTERNAL

                    ? UP_ferror((FILE *)b->ptr)

                    : ferror((FILE *)b->ptr))) {

            ERR_raise_data(ERR_LIB_SYS, get_last_sys_error(),

                "calling fread()");

            ERR_raise(ERR_LIB_BIO, ERR_R_SYS_LIB);

            ret = -1;

        }

    }

    return ret;

}

static int file_write(BIO *b, const char *in, int inl)

{

    int ret = 0;

    if (b->init && (in != NULL)) {

        if (b->flags & BIO_FLAGS_UPLINK_INTERNAL)

            ret = (int)UP_fwrite(in, inl, 1, b->ptr);

        else

            ret = (int)fwrite(in, inl, 1, (FILE *)b->ptr);

        if (ret)

            ret = inl;

        /* ret=fwrite(in,1,(int)inl,(FILE *)b->ptr); */

        /*

         * according to Tim Hudson <tjh@openssl.org>, the commented out

         * version above can cause 'inl' write calls under some stupid stdio

         * implementations (VMS)

         */

    }

    return ret;

}

static long file_ctrl(BIO *b, int cmd, long num, void *ptr)

{

    long ret = 1;

    FILE *fp = (FILE *)b->ptr;

    FILE **fpp;

    char p[4];

    int st;

#if defined(OPENSSL_SYS_WINDOWS)

    int oldErr;

#endif

    switch (cmd) {

    case BIO_C_FILE_SEEK:

    case BIO_CTRL_RESET:

        if (b->flags & BIO_FLAGS_UPLINK_INTERNAL)

            ret = (long)UP_fseek(b->ptr, num, 0);

        else

            ret = (long)fseek(fp, num, 0);

        break;

    case BIO_CTRL_EOF:

        /*

         * NOTE feof returns 0 if we're not in an eof condition

         * and a non-zero value if we are (i.e. any non-zero value

         * so we map the 0:non-0 return value here to 0:1 with a

         * double negation

         */

#if defined(OPENSSL_SYS_WINDOWS)

        oldErr = errno;

        errno = 0;

#endif

        if (b->flags & BIO_FLAGS_UPLINK_INTERNAL)

            ret = !!(long)UP_feof(fp);

        else

            ret = !!(long)feof(fp);

#if defined(OPENSSL_SYS_WINDOWS)

        /*

         * Windows gives us an extra issue to contend with.

         * In windows feof may return 0 if it is passed an invalid

         * stream.  In this event, feof sets errno to EINVAL.

         * Check for that here, and set ret to -EINVAL if its the case.

         */

        if (ret == 0 && errno == EINVAL)

            ret = -EINVAL;

        else if (errno == 0)

            errno = oldErr;

#endif

        break;

    case BIO_C_FILE_TELL:

    case BIO_CTRL_INFO:

        if (b->flags & BIO_FLAGS_UPLINK_INTERNAL)

            ret = UP_ftell(b->ptr);

        else {

#if defined(OPENSSL_SYS_WINDOWS)

            /*

             * On Windows, for non-seekable files (stdin), ftell() is undefined.

             */

            if (GetFileType((HANDLE)_get_osfhandle(_fileno(fp))) != FILE_TYPE_DISK)

                ret = -1;

            else

                ret = ftell(fp);

#else

            ret = ftell(fp);

#endif

        }

        break;

    case BIO_C_SET_FILE_PTR:

        file_free(b);

        b->shutdown = (int)num & BIO_CLOSE;

        b->ptr = ptr;

        b->init = 1;

#if BIO_FLAGS_UPLINK_INTERNAL != 0

#if defined(__MINGW32__) && defined(__MSVCRT__) && !defined(_IOB_ENTRIES)

#define _IOB_ENTRIES 20

#endif

        /* Safety net to catch purely internal BIO_set_fp calls */

#if (defined(_MSC_VER) && _MSC_VER >= 1900) || defined(__BORLANDC__)

        if (ptr == stdin || ptr == stdout || ptr == stderr)

            BIO_clear_flags(b, BIO_FLAGS_UPLINK_INTERNAL);

#elif defined(_IOB_ENTRIES)

        if ((size_t)ptr >= (size_t)stdin && (size_t)ptr < (size_t)(stdin + _IOB_ENTRIES))

            BIO_clear_flags(b, BIO_FLAGS_UPLINK_INTERNAL);

#endif

#endif

#ifdef UP_fsetmod

        if (b->flags & BIO_FLAGS_UPLINK_INTERNAL)

            UP_fsetmod(b->ptr, (char)((num & BIO_FP_TEXT) ? 't' : 'b'));

        else

#endif

        {

#if defined(OPENSSL_SYS_WINDOWS)

            int fd = _fileno((FILE *)ptr);

            if (num & BIO_FP_TEXT)

                _setmode(fd, _O_TEXT);

            else

                _setmode(fd, _O_BINARY);

#elif defined(OPENSSL_SYS_MSDOS)

            int fd = fileno((FILE *)ptr);

            /* Set correct text/binary mode */

            if (num & BIO_FP_TEXT)

                _setmode(fd, _O_TEXT);

            /* Dangerous to set stdin/stdout to raw (unless redirected) */

            else {

                if (fd == STDIN_FILENO || fd == STDOUT_FILENO) {

                    if (isatty(fd) <= 0)

                        _setmode(fd, _O_BINARY);

                } else

                    _setmode(fd, _O_BINARY);

            }

#elif defined(OPENSSL_SYS_WIN32_CYGWIN)

            int fd = fileno((FILE *)ptr);

            if (!(num & BIO_FP_TEXT))

                setmode(fd, O_BINARY);

#endif

        }

        break;

    case BIO_C_SET_FILENAME:

        file_free(b);

        b->shutdown = (int)num & BIO_CLOSE;

        if (num & BIO_FP_APPEND) {

            if (num & BIO_FP_READ)

                OPENSSL_strlcpy(p, "a+", sizeof(p));

            else

                OPENSSL_strlcpy(p, "a", sizeof(p));

        } else if ((num & BIO_FP_READ) && (num & BIO_FP_WRITE))

            OPENSSL_strlcpy(p, "r+", sizeof(p));

        else if (num & BIO_FP_WRITE)

            OPENSSL_strlcpy(p, "w", sizeof(p));

        else if (num & BIO_FP_READ)

            OPENSSL_strlcpy(p, "r", sizeof(p));

        else {

            ERR_raise(ERR_LIB_BIO, BIO_R_BAD_FOPEN_MODE);

            ret = 0;

            break;

        }

#if defined(OPENSSL_SYS_MSDOS) || defined(OPENSSL_SYS_WINDOWS)

        if (!(num & BIO_FP_TEXT))

            OPENSSL_strlcat(p, "b", sizeof(p));

        else

            OPENSSL_strlcat(p, "t", sizeof(p));

#elif defined(OPENSSL_SYS_WIN32_CYGWIN)

        if (!(num & BIO_FP_TEXT))

            OPENSSL_strlcat(p, "b", sizeof(p));

#endif

        if (ptr == NULL) {

            ERR_raise(ERR_LIB_CRYPTO, ERR_R_PASSED_NULL_PARAMETER);

            ret = 0;

            break;

        }

        fp = openssl_fopen(ptr, p);

        if (fp == NULL) {

            ERR_raise_data(ERR_LIB_SYS, get_last_sys_error(),

                "calling fopen(%s, %s)",

                (const char *)ptr, p);

            ERR_raise(ERR_LIB_BIO, ERR_R_SYS_LIB);

            ret = 0;

            break;

        }

        b->ptr = fp;

        b->init = 1;

        /* we did fopen -> we disengage UPLINK */

        BIO_clear_flags(b, BIO_FLAGS_UPLINK_INTERNAL);

        break;

    case BIO_C_GET_FILE_PTR:

        /* the ptr parameter is actually a FILE ** in this case. */

        if (ptr != NULL) {

            fpp = (FILE **)ptr;

            if (BIO_FLAGS_UPLINK_INTERNAL == 0

                || b->flags & BIO_FLAGS_UPLINK_INTERNAL) {

                *fpp = (FILE *)b->ptr;

            } else { /* avoid returning internal FILE * to the app */

                *fpp = NULL;

                ret = 0;

            }

        }

        break;

    case BIO_CTRL_GET_CLOSE:

        ret = (long)b->shutdown;

        break;

    case BIO_CTRL_SET_CLOSE:

        b->shutdown = (int)num;

        break;

    case BIO_CTRL_FLUSH:

        st = b->flags & BIO_FLAGS_UPLINK_INTERNAL

            ? UP_fflush(b->ptr)

            : fflush((FILE *)b->ptr);

        if (st == EOF) {

            ERR_raise_data(ERR_LIB_SYS, get_last_sys_error(),

                "calling fflush()");

            ERR_raise(ERR_LIB_BIO, ERR_R_SYS_LIB);

            ret = 0;

        }

        break;

    case BIO_CTRL_DUP:

        ret = 1;

        break;

    case BIO_CTRL_WPENDING:

    case BIO_CTRL_PENDING:

    case BIO_CTRL_PUSH:

    case BIO_CTRL_POP:

    default:

        ret = 0;

        break;

    }

    return ret;

}

static int file_gets(BIO *bp, char *buf, int size)

{

    int ret = 0;

    buf[0] = '\0';

    if (bp->flags & BIO_FLAGS_UPLINK_INTERNAL) {

        if (!UP_fgets(buf, size, bp->ptr))

            goto err;

    } else {

        if (!fgets(buf, size, (FILE *)bp->ptr))

            goto err;

    }

    if (buf[0] != '\0')

        ret = (int)strlen(buf);

err:

    return ret;

}

static int file_puts(BIO *bp, const char *str)

{

    int ret;

    size_t n = strlen(str);

    if (n > INT_MAX)

        return -1;

    ret = file_write(bp, str, (int)n);

    return ret;

}

#else

static int file_write(BIO *b, const char *in, int inl)

{

    return -1;

}

static int file_read(BIO *b, char *out, int outl)

{

    return -1;

}

static int file_puts(BIO *bp, const char *str)

{

    return -1;

}

static int file_gets(BIO *bp, char *buf, int size)

{

    return 0;

}

static long file_ctrl(BIO *b, int cmd, long num, void *ptr)

{

    return 0;

}

static int file_new(BIO *bi)

{

    return 0;

}

static int file_free(BIO *a)

{

    return 0;

}

static const BIO_METHOD methods_filep = {

    BIO_TYPE_FILE,

    "FILE pointer",

    bwrite_conv,

    file_write,

    bread_conv,

    file_read,

    file_puts,

    file_gets,

    file_ctrl,

    file_new,

    file_free,

    NULL, /* file_callback_ctrl */

};

const BIO_METHOD *BIO_s_file(void)

{

    return &methods_filep;

}

BIO *BIO_new_file(const char *filename, const char *mode)

{

    return NULL;

}

#endif /* OPENSSL_NO_STDIO */