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Diffstat (limited to 'contrib/file/src/fsmagic.c')
| -rw-r--r-- | contrib/file/src/fsmagic.c | 407 |
1 files changed, 407 insertions, 0 deletions
diff --git a/contrib/file/src/fsmagic.c b/contrib/file/src/fsmagic.c new file mode 100644 index 000000000000..ef5492f2a106 --- /dev/null +++ b/contrib/file/src/fsmagic.c @@ -0,0 +1,407 @@ +/* + * Copyright (c) Ian F. Darwin 1986-1995. + * Software written by Ian F. Darwin and others; + * maintained 1995-present by Christos Zoulas and others. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice immediately at the beginning of the file, without modification, + * this list of conditions, and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR + * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ +/* + * fsmagic - magic based on filesystem info - directory, special files, etc. + */ + +#include "file.h" + +#ifndef lint +FILE_RCSID("@(#)$File: fsmagic.c,v 1.73 2014/05/14 23:15:42 christos Exp $") +#endif /* lint */ + +#include "magic.h" +#include <string.h> +#ifdef HAVE_UNISTD_H +#include <unistd.h> +#endif +#include <stdlib.h> +/* Since major is a function on SVR4, we cannot use `ifndef major'. */ +#ifdef MAJOR_IN_MKDEV +# include <sys/mkdev.h> +# define HAVE_MAJOR +#endif +#ifdef MAJOR_IN_SYSMACROS +# include <sys/sysmacros.h> +# define HAVE_MAJOR +#endif +#ifdef major /* Might be defined in sys/types.h. */ +# define HAVE_MAJOR +#endif +#ifdef WIN32 +# define WIN32_LEAN_AND_MEAN +# include <windows.h> +#endif + +#ifndef HAVE_MAJOR +# define major(dev) (((dev) >> 8) & 0xff) +# define minor(dev) ((dev) & 0xff) +#endif +#undef HAVE_MAJOR +#ifdef S_IFLNK +private int +bad_link(struct magic_set *ms, int err, char *buf) +{ + int mime = ms->flags & MAGIC_MIME; + if ((mime & MAGIC_MIME_TYPE) && + file_printf(ms, "inode/symlink") + == -1) + return -1; + else if (!mime) { + if (ms->flags & MAGIC_ERROR) { + file_error(ms, err, + "broken symbolic link to `%s'", buf); + return -1; + } + if (file_printf(ms, "broken symbolic link to `%s'", buf) == -1) + return -1; + } + return 1; +} +#endif +private int +handle_mime(struct magic_set *ms, int mime, const char *str) +{ + if ((mime & MAGIC_MIME_TYPE)) { + if (file_printf(ms, "inode/%s", str) == -1) + return -1; + if ((mime & MAGIC_MIME_ENCODING) && file_printf(ms, + "; charset=") == -1) + return -1; + } + if ((mime & MAGIC_MIME_ENCODING) && file_printf(ms, "binary") == -1) + return -1; + return 0; +} + +protected int +file_fsmagic(struct magic_set *ms, const char *fn, struct stat *sb) +{ + int ret, did = 0; + int mime = ms->flags & MAGIC_MIME; +#ifdef S_IFLNK + char buf[BUFSIZ+4]; + ssize_t nch; + struct stat tstatbuf; +#endif + + if (ms->flags & MAGIC_APPLE) + return 0; + if (fn == NULL) + return 0; + +#define COMMA (did++ ? ", " : "") + /* + * Fstat is cheaper but fails for files you don't have read perms on. + * On 4.2BSD and similar systems, use lstat() to identify symlinks. + */ +#ifdef S_IFLNK + if ((ms->flags & MAGIC_SYMLINK) == 0) + ret = lstat(fn, sb); + else +#endif + ret = stat(fn, sb); /* don't merge into if; see "ret =" above */ + +#ifdef WIN32 + { + HANDLE hFile = CreateFile(fn, 0, FILE_SHARE_DELETE | + FILE_SHARE_READ | FILE_SHARE_WRITE, NULL, OPEN_EXISTING, 0, + NULL); + if (hFile != INVALID_HANDLE_VALUE) { + /* + * Stat failed, but we can still open it - assume it's + * a block device, if nothing else. + */ + if (ret) { + sb->st_mode = S_IFBLK; + ret = 0; + } + switch (GetFileType(hFile)) { + case FILE_TYPE_CHAR: + sb->st_mode |= S_IFCHR; + sb->st_mode &= ~S_IFREG; + break; + case FILE_TYPE_PIPE: + sb->st_mode |= S_IFIFO; + sb->st_mode &= ~S_IFREG; + break; + } + CloseHandle(hFile); + } + } +#endif + + if (ret) { + if (ms->flags & MAGIC_ERROR) { + file_error(ms, errno, "cannot stat `%s'", fn); + return -1; + } + if (file_printf(ms, "cannot open `%s' (%s)", + fn, strerror(errno)) == -1) + return -1; + return 0; + } + + ret = 1; + if (!mime) { +#ifdef S_ISUID + if (sb->st_mode & S_ISUID) + if (file_printf(ms, "%ssetuid", COMMA) == -1) + return -1; +#endif +#ifdef S_ISGID + if (sb->st_mode & S_ISGID) + if (file_printf(ms, "%ssetgid", COMMA) == -1) + return -1; +#endif +#ifdef S_ISVTX + if (sb->st_mode & S_ISVTX) + if (file_printf(ms, "%ssticky", COMMA) == -1) + return -1; +#endif + } + + switch (sb->st_mode & S_IFMT) { + case S_IFDIR: + if (mime) { + if (handle_mime(ms, mime, "directory") == -1) + return -1; + } else if (file_printf(ms, "%sdirectory", COMMA) == -1) + return -1; + break; +#ifdef S_IFCHR + case S_IFCHR: + /* + * If -s has been specified, treat character special files + * like ordinary files. Otherwise, just report that they + * are block special files and go on to the next file. + */ + if ((ms->flags & MAGIC_DEVICES) != 0) { + ret = 0; + break; + } + if (mime) { + if (handle_mime(ms, mime, "chardevice") == -1) + return -1; + } else { +#ifdef HAVE_STRUCT_STAT_ST_RDEV +# ifdef dv_unit + if (file_printf(ms, "%scharacter special (%d/%d/%d)", + COMMA, major(sb->st_rdev), dv_unit(sb->st_rdev), + dv_subunit(sb->st_rdev)) == -1) + return -1; +# else + if (file_printf(ms, "%scharacter special (%ld/%ld)", + COMMA, (long)major(sb->st_rdev), + (long)minor(sb->st_rdev)) == -1) + return -1; +# endif +#else + if (file_printf(ms, "%scharacter special", COMMA) == -1) + return -1; +#endif + } + break; +#endif +#ifdef S_IFBLK + case S_IFBLK: + /* + * If -s has been specified, treat block special files + * like ordinary files. Otherwise, just report that they + * are block special files and go on to the next file. + */ + if ((ms->flags & MAGIC_DEVICES) != 0) { + ret = 0; + break; + } + if (mime) { + if (handle_mime(ms, mime, "blockdevice") == -1) + return -1; + } else { +#ifdef HAVE_STRUCT_STAT_ST_RDEV +# ifdef dv_unit + if (file_printf(ms, "%sblock special (%d/%d/%d)", + COMMA, major(sb->st_rdev), dv_unit(sb->st_rdev), + dv_subunit(sb->st_rdev)) == -1) + return -1; +# else + if (file_printf(ms, "%sblock special (%ld/%ld)", + COMMA, (long)major(sb->st_rdev), + (long)minor(sb->st_rdev)) == -1) + return -1; +# endif +#else + if (file_printf(ms, "%sblock special", COMMA) == -1) + return -1; +#endif + } + break; +#endif + /* TODO add code to handle V7 MUX and Blit MUX files */ +#ifdef S_IFIFO + case S_IFIFO: + if((ms->flags & MAGIC_DEVICES) != 0) + break; + if (mime) { + if (handle_mime(ms, mime, "fifo") == -1) + return -1; + } else if (file_printf(ms, "%sfifo (named pipe)", COMMA) == -1) + return -1; + break; +#endif +#ifdef S_IFDOOR + case S_IFDOOR: + if (mime) { + if (handle_mime(ms, mime, "door") == -1) + return -1; + } else if (file_printf(ms, "%sdoor", COMMA) == -1) + return -1; + break; +#endif +#ifdef S_IFLNK + case S_IFLNK: + if ((nch = readlink(fn, buf, BUFSIZ-1)) <= 0) { + if (ms->flags & MAGIC_ERROR) { + file_error(ms, errno, "unreadable symlink `%s'", + fn); + return -1; + } + if (mime) { + if (handle_mime(ms, mime, "symlink") == -1) + return -1; + } else if (file_printf(ms, + "%sunreadable symlink `%s' (%s)", COMMA, fn, + strerror(errno)) == -1) + return -1; + break; + } + buf[nch] = '\0'; /* readlink(2) does not do this */ + + /* If broken symlink, say so and quit early. */ + if (*buf == '/') { + if (stat(buf, &tstatbuf) < 0) + return bad_link(ms, errno, buf); + } else { + char *tmp; + char buf2[BUFSIZ+BUFSIZ+4]; + + if ((tmp = strrchr(fn, '/')) == NULL) { + tmp = buf; /* in current directory anyway */ + } else { + if (tmp - fn + 1 > BUFSIZ) { + if (ms->flags & MAGIC_ERROR) { + file_error(ms, 0, + "path too long: `%s'", buf); + return -1; + } + if (mime) { + if (handle_mime(ms, mime, + "x-path-too-long") == -1) + return -1; + } else if (file_printf(ms, + "%spath too long: `%s'", COMMA, + fn) == -1) + return -1; + break; + } + /* take dir part */ + (void)strlcpy(buf2, fn, sizeof buf2); + buf2[tmp - fn + 1] = '\0'; + /* plus (rel) link */ + (void)strlcat(buf2, buf, sizeof buf2); + tmp = buf2; + } + if (stat(tmp, &tstatbuf) < 0) + return bad_link(ms, errno, buf); + } + + /* Otherwise, handle it. */ + if ((ms->flags & MAGIC_SYMLINK) != 0) { + const char *p; + ms->flags &= MAGIC_SYMLINK; + p = magic_file(ms, buf); + ms->flags |= MAGIC_SYMLINK; + if (p == NULL) + return -1; + } else { /* just print what it points to */ + if (mime) { + if (handle_mime(ms, mime, "symlink") == -1) + return -1; + } else if (file_printf(ms, "%ssymbolic link to `%s'", + COMMA, buf) == -1) + return -1; + } + break; +#endif +#ifdef S_IFSOCK +#ifndef __COHERENT__ + case S_IFSOCK: + if (mime) { + if (handle_mime(ms, mime, "socket") == -1) + return -1; + } else if (file_printf(ms, "%ssocket", COMMA) == -1) + return -1; + break; +#endif +#endif + case S_IFREG: + /* + * regular file, check next possibility + * + * If stat() tells us the file has zero length, report here that + * the file is empty, so we can skip all the work of opening and + * reading the file. + * But if the -s option has been given, we skip this + * optimization, since on some systems, stat() reports zero + * size for raw disk partitions. (If the block special device + * really has zero length, the fact that it is empty will be + * detected and reported correctly when we read the file.) + */ + if ((ms->flags & MAGIC_DEVICES) == 0 && sb->st_size == 0) { + if (mime) { + if (handle_mime(ms, mime, "x-empty") == -1) + return -1; + } else if (file_printf(ms, "%sempty", COMMA) == -1) + return -1; + break; + } + ret = 0; + break; + + default: + file_error(ms, 0, "invalid mode 0%o", sb->st_mode); + return -1; + /*NOTREACHED*/ + } + + if (!mime && did && ret == 0) { + if (file_printf(ms, " ") == -1) + return -1; + } + return ret; +} |