From 3ea540c7570a76bf72ae697c4040e77dad5bea6d Mon Sep 17 00:00:00 2001 From: Jim Meyering Date: Fri, 5 Jan 2007 18:23:54 +0100 Subject: ls: Add support for SELinux and a slightly modified -Z option. I started with the patches from Red Hat. The entries below tell how the code evolved. * src/ls.c (print_long_format, print_file_name_and_frills): When there is no security context (due to getfilecon/lgetfilecon failing with e.g. ENOTSUP), print it as "?", not "". * src/ls.c (print_file_name_and_frills): Make -Z work without -l. (length_of_file_name_and_frills): Likewise. * src/ls.c: Remove the --lcontext and --scontext options. Change the way -Z, --context work so that it no longer implies -l. Thus, -Z -l will work like -lcontext and -Z without -l will work like --scontext. Adjust tests to reflect new 'ls -l' syntax -- affects only systems with SELinux when operating on a file with no ACL. These tests assumed that everything before the first space on each line is the 10-byte mode string. But there may also be a "+" in the 11th column, just before the space. However, note that this is not new. The same thing would have happened even without the change below, when listing a file with an ACL. * tests/chmod/equals, tests/cp/cp-parents, tests/cp/fail-perm: * tests/cp/link-preserve, tests/install/basic-1, tests/misc/mknod: * tests/mkdir/parents, tests/mkdir/special-1, tests/mv/partition-perm: Don't make compilation depend on USE_ACL. An SELinux security context counts as an "alternate access control method", so ls must output a "+" for each file with a security context. * src/ls.c [struct fileinfo] (have_acl): Declare unconditionally. (FILE_HAS_ACL): Remove macro definition. Use f->have_acl directly. (gobble_file): Record whether a file has a security context, and update the condition used to determine whether to print the "+". (gobble_file): Call getfilecon/lgetfilecon also when format == long_format, so that we get the "+". * src/ls.c (gobble_file): Add a comment explaining why (with a security context option) ls doesn't exit nonzero due to e.g., getfilecon failing with errno == ENOTSUP. * src/ls.c (gobble_file): Ignore failure of getfilecon if it's due to ENOTSUP. * src/ls.c (gobble_file): Factor out three small blocks using getfilecon and lgetfilecon. Don't ignore return value from getfilecon and lgetfilecon. * src/ls.c (print_long_format): Don't use ?: (empty 2nd arg with C ternary operator). (print_scontext_format): Likewise. (print_scontext): Declare to be "bool", not int. Adjust uses. * src/Makefile.am (dir_LDADD, ls_LDADD, vdir_LDADD): Add $(LIB_SELINUX). * tests/misc/chcon: New file. * tests/misc/chcon-fail: New file. * tests/Makefile.am (check-root): Run new, root-only misc/chcon test. * tests/misc/Makefile.am (TESTS): Add chcon and chcon-fail. * tests/misc/Makefile.am (TESTS): Add selinux. * tests/misc/selinux: New file. * tests/help-version: Skip chcon. --- src/Makefile.am | 6 ++-- src/ls.c | 90 ++++++++++++++++++++++++++++++++++++++++++--------------- 2 files changed, 70 insertions(+), 26 deletions(-) (limited to 'src') diff --git a/src/Makefile.am b/src/Makefile.am index 6a740b65b..8d2580631 100644 --- a/src/Makefile.am +++ b/src/Makefile.am @@ -72,12 +72,12 @@ __LDADD = $(LDADD) $(LIB_EACCESS) # for clock_gettime and fdatasync dd_LDADD = $(LDADD) $(LIB_GETHRXTIME) $(LIB_FDATASYNC) -dir_LDADD = $(LDADD) $(LIB_CLOCK_GETTIME) -ls_LDADD = $(LDADD) $(LIB_CLOCK_GETTIME) +dir_LDADD = $(LDADD) $(LIB_CLOCK_GETTIME) $(LIB_SELINUX) +ls_LDADD = $(LDADD) $(LIB_CLOCK_GETTIME) $(LIB_SELINUX) pr_LDADD = $(LDADD) $(LIB_CLOCK_GETTIME) shred_LDADD = $(LDADD) $(LIB_GETHRXTIME) $(LIB_FDATASYNC) shuf_LDADD = $(LDADD) $(LIB_GETHRXTIME) -vdir_LDADD = $(LDADD) $(LIB_CLOCK_GETTIME) +vdir_LDADD = $(LDADD) $(LIB_CLOCK_GETTIME) $(LIB_SELINUX) ## If necessary, add -lm to resolve use of pow in lib/strtod.c. sort_LDADD = $(LDADD) $(POW_LIB) $(LIB_GETHRXTIME) diff --git a/src/ls.c b/src/ls.c index 77abf67be..f8727a246 100644 --- a/src/ls.c +++ b/src/ls.c @@ -61,6 +61,7 @@ #include #include #include +#include /* Use SA_NOCLDSTOP as a proxy for whether the sigaction machinery is present. */ @@ -167,24 +168,20 @@ struct fileinfo zero. */ mode_t linkmode; + /* SELinux security context. */ + security_context_t scontext; + bool stat_ok; /* For symbolic link and color printing, true if linked-to file exists, otherwise false. */ bool linkok; -#if USE_ACL - /* For long listings, true if the file has an access control list. */ + /* For long listings, true if the file has an access control list, + or an SELinux security context. */ bool have_acl; -#endif }; -#if USE_ACL -# define FILE_HAS_ACL(F) ((F)->have_acl) -#else -# define FILE_HAS_ACL(F) 0 -#endif - #define LEN_STR_PAIR(s) sizeof (s) - 1, s /* Null is a valid character in a color indicator (think about Epson @@ -320,14 +317,12 @@ static struct pending *pending_dirs; static time_t current_time = TYPE_MINIMUM (time_t); static int current_time_ns = -1; +static bool print_scontext; + /* Whether any of the files has an ACL. This affects the width of the mode column. */ -#if USE_ACL static bool any_has_acl; -#else -enum { any_has_acl = false }; -#endif /* The number of columns to use for columns containing inode numbers, block sizes, link counts, owners, groups, authors, major device @@ -336,6 +331,7 @@ enum { any_has_acl = false }; static int inode_number_width; static int block_size_width; static int nlink_width; +static int scontext_width; static int owner_width; static int group_width; static int author_width; @@ -787,6 +783,7 @@ static struct option const long_options[] = {"time-style", required_argument, NULL, TIME_STYLE_OPTION}, {"color", optional_argument, NULL, COLOR_OPTION}, {"block-size", required_argument, NULL, BLOCK_SIZE_OPTION}, + {"context", no_argument, 0, 'Z'}, {"author", no_argument, NULL, AUTHOR_OPTION}, {GETOPT_HELP_OPTION_DECL}, {GETOPT_VERSION_OPTION_DECL}, @@ -1246,6 +1243,7 @@ main (int argc, char **argv) format_needs_stat = sort_type == sort_time || sort_type == sort_size || format == long_format + || print_scontext || print_block_size; format_needs_type = (! format_needs_stat && (recursive @@ -1439,6 +1437,7 @@ decode_switches (int argc, char **argv) ignore_mode = IGNORE_DEFAULT; ignore_patterns = NULL; hide_patterns = NULL; + print_scontext = false; /* FIXME: put this in a function. */ { @@ -1514,7 +1513,7 @@ decode_switches (int argc, char **argv) } while ((c = getopt_long (argc, argv, - "abcdfghiklmnopqrstuvw:xABCDFGHI:LNQRST:UX1", + "abcdfghiklmnopqrstuvw:xABCDFGHI:LNQRST:UXZ1", long_options, NULL)) != -1) { switch (c) @@ -1813,6 +1812,10 @@ decode_switches (int argc, char **argv) file_output_block_size = output_block_size = 1; break; + case 'Z': + print_scontext = true; + break; + case_GETOPT_HELP_CHAR; case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS); @@ -2516,18 +2519,22 @@ clear_files (void) struct fileinfo *f = sorted_file[i]; free (f->name); free (f->linkname); + if (f->scontext) + { + freecon (f->scontext); + f->scontext = NULL; + } } cwd_n_used = 0; -#if USE_ACL any_has_acl = false; -#endif inode_number_width = 0; block_size_width = 0; nlink_width = 0; owner_width = 0; group_width = 0; author_width = 0; + scontext_width = 0; major_device_number_width = 0; minor_device_number_width = 0; file_size_width = 0; @@ -2591,7 +2598,7 @@ gobble_file (char const *name, enum filetype type, ino_t inode, { /* Absolute name of this file. */ char *absolute_name; - + bool do_deref; int err; if (name[0] == '/' || dirname[0] == 0) @@ -2606,6 +2613,7 @@ gobble_file (char const *name, enum filetype type, ino_t inode, { case DEREF_ALWAYS: err = stat (absolute_name, &f->stat); + do_deref = true; break; case DEREF_COMMAND_LINE_ARGUMENTS: @@ -2614,6 +2622,7 @@ gobble_file (char const *name, enum filetype type, ino_t inode, { bool need_lstat; err = stat (absolute_name, &f->stat); + do_deref = true; if (dereference == DEREF_COMMAND_LINE_ARGUMENTS) break; @@ -2632,9 +2641,27 @@ gobble_file (char const *name, enum filetype type, ino_t inode, default: /* DEREF_NEVER */ err = lstat (absolute_name, &f->stat); + do_deref = false; break; } + bool file_has_security_context = false; + if (err == 0 && (format == long_format || print_scontext)) + { + int attr_len = (do_deref + ? getfilecon (absolute_name, &f->scontext) + : lgetfilecon (absolute_name, &f->scontext)); + err = (attr_len < 0); + file_has_security_context = (err == 0); + + /* When requesting security context information, don't make + ls fail just because the file (even a command line argument) + isn't on the right type of file system. I.e., a getfilecon + failure isn't in the same class as a stat failure. */ + if (err && errno == ENOTSUP) + err = 0; + } + if (err != 0) { /* Failure to stat a command line argument leads to @@ -2653,16 +2680,14 @@ gobble_file (char const *name, enum filetype type, ino_t inode, f->stat_ok = true; -#if USE_ACL if (format == long_format) { int n = file_has_acl (absolute_name, &f->stat); - f->have_acl = (0 < n); + f->have_acl = (0 < n || file_has_security_context); any_has_acl |= f->have_acl; if (n < 0) error (0, errno, "%s", quotearg_colon (absolute_name)); } -#endif if (S_ISLNK (f->stat.st_mode) && (format == long_format || check_symlink_color)) @@ -2738,6 +2763,13 @@ gobble_file (char const *name, enum filetype type, ino_t inode, author_width = len; } + if (print_scontext) + { + int len = f->scontext ? strlen (f->scontext) : 0; + if (scontext_width < len) + scontext_width = len; + } + { char buf[INT_BUFSIZE_BOUND (uintmax_t)]; int len = strlen (umaxtostr (f->stat.st_nlink, buf)); @@ -3387,7 +3419,7 @@ print_long_format (const struct fileinfo *f) struct tm *when_local; /* Compute the mode string, except remove the trailing space if no - files in this directory have ACLs. */ + file in this directory has an ACL or SELinux security context. */ if (f->stat_ok) filemodestring (&f->stat, modebuf); else @@ -3398,7 +3430,7 @@ print_long_format (const struct fileinfo *f) } if (! any_has_acl) modebuf[10] = '\0'; - else if (FILE_HAS_ACL (f)) + else if (f->have_acl) modebuf[10] = '+'; switch (time_type) @@ -3463,7 +3495,7 @@ print_long_format (const struct fileinfo *f) DIRED_INDENT (); - if (print_owner | print_group | print_author) + if (print_owner | print_group | print_author | print_scontext) { DIRED_FPUTS (buf, stdout, p - buf); @@ -3476,6 +3508,10 @@ print_long_format (const struct fileinfo *f) if (print_author) format_user (f->stat.st_author, author_width, f->stat_ok); + if (print_scontext) + format_user_or_group ((f->scontext ? f->scontext : "?"), + 0, scontext_width); + p = buf; } @@ -3812,6 +3848,10 @@ print_file_name_and_frills (const struct fileinfo *f) human_readable (ST_NBLOCKS (f->stat), buf, human_output_opts, ST_NBLOCKSIZE, output_block_size)); + if (print_scontext) + printf ("%*s ", format == with_commas ? 0 : scontext_width, + (f->scontext ? f->scontext : "?")); + print_name_with_quoting (f->name, FILE_OR_LINK_MODE (f), f->linkok, f->stat_ok, f->filetype, NULL); @@ -3975,6 +4015,9 @@ length_of_file_name_and_frills (const struct fileinfo *f) output_block_size)) : block_size_width); + if (print_scontext) + len += 1 + (format == with_commas ? strlen (f->scontext) : scontext_width); + quote_name (NULL, f->name, filename_quoting_options, &name_width); len += name_width; @@ -4403,6 +4446,7 @@ Mandatory arguments to long options are mandatory for short options too.\n\ -w, --width=COLS assume screen width instead of current value\n\ -x list entries by lines instead of by columns\n\ -X sort alphabetically by entry extension\n\ + -Z, --context print any SELinux security context of each file\n\ -1 list one file per line\n\ "), stdout); fputs (HELP_OPTION_DESCRIPTION, stdout); -- cgit v1.2.3-54-g00ecf