From c565b06325960a16ebf44afd8ae73f363775e58d Mon Sep 17 00:00:00 2001 From: Rob Landley Date: Mon, 18 May 2015 02:00:43 -0500 Subject: More ls -Z upgrading. Move TOYBOX_SELINUX and TOYBOX_SMACK support from portability.h to new lib/lsm.h. Update ls.c to use it. Fix "ls . toys" (two directories when one is . or ..), which was filtering out the . as something we shouldn't recurse into even though it was explicitly listed on the command line. For some reason "ls -Z . toys" is still segfaulting though (but "ls -Z ." isn't), need to figure out why... --- lib/lsm.h | 96 +++++++++++++++++++++++++++++++++++++++++++++++ lib/portability.h | 25 ++----------- toys/posix/ls.c | 109 +++++++++++++++++++++++------------------------------- 3 files changed, 146 insertions(+), 84 deletions(-) create mode 100644 lib/lsm.h diff --git a/lib/lsm.h b/lib/lsm.h new file mode 100644 index 00000000..b16138a4 --- /dev/null +++ b/lib/lsm.h @@ -0,0 +1,96 @@ +/* lsm.h - header file for lib directory + * + * Copyright 2015 Rob Landley + */ + +#if CFG_TOYBOX_SELINUX +#include +#else +#define is_selinux_enabled() 0 +#define getcon(...) (-1) +#define getfilecon(...) (-1) +#define lgetfilecon(...) (-1) +#define fgetfilecon(...) (-1) +#define setfilecon(...) (-1) +#define lsetfilecon(...) (-1) +#define fsetfilecon(...) (-1) +#endif + +#if CFG_TOYBOX_SMACK +#include +#include +#include +#else +#define XATTR_NAME_SMACK 0 +//ssize_t fgetxattr (int fd, char *name, void *value, size_t size); +#define smack_smackfs_path(...) (-1) +#define smack_new_label_from_self(...) (-1) +#define smack_new_label_from_path(...) (-1) +#define smack_new_label_from_file(...) (-1) +#define smack_set_label_for_path(...) (-1) +#define smack_set_label_for_file(...) (-1) +#endif + +// This turns into "return 0" when no LSM and lets code optimize out. +static inline int lsm_enabled(void) +{ + if (CFG_TOYBOX_SMACK) return !!smack_smackfs_path(); + else return is_selinux_enabled() == 1; +} + +// Fetch this process's lsm context +static inline char *lsm_context(void) +{ + int ok = 0; + char *result; + + if (CFG_TOYBOX_SMACK) ok = smack_new_label_from_self(&result) > 0; + else ok = getcon(&result) == 0; + + return ok ? result : strdup("?"); +} + +static inline int lsm_set_context(char *filename, char *context) +{ + if (CFG_TOYBOX_SMACK) + return smack_set_label_for_path(filename, XATTR_NAME_SMACK, 1, context); + else return setfilecon(filename, context); +} + +static inline int lsm_lset_context(char *filename, char *context) +{ + if (CFG_TOYBOX_SMACK) + return smack_set_label_for_path(filename, XATTR_NAME_SMACK, 0, context); + else return lsetfilecon(filename, context); +} + +static inline int lsm_fset_context(int file, char *context) +{ + if (CFG_TOYBOX_SMACK) + return smack_set_label_for_file(file, XATTR_NAME_SMACK, context); + else return fsetfilecon(file, context); +} + + +// returns -1 in case of error or else the length of the context */ +// context can be NULL to get the length only */ +static inline int lsm_get_context(char *filename, char **context) +{ + if (CFG_TOYBOX_SMACK) + return smack_new_label_from_path(filename, XATTR_NAME_SMACK, 1, context); + else return getfilecon(filename, context); +} + +static inline int lsm_lget_context(char *filename, char **context) +{ + if (CFG_TOYBOX_SMACK) + return smack_new_label_from_path(filename, XATTR_NAME_SMACK, 0, context); + else return lgetfilecon(filename, context); +} + +static inline int lsm_fget_context(int file, char **context) +{ + if (CFG_TOYBOX_SMACK) + return smack_new_label_from_file(file, XATTR_NAME_SMACK, context); + return fgetfilecon(file, context); +} diff --git a/lib/portability.h b/lib/portability.h index aa1ee488..f83cab60 100644 --- a/lib/portability.h +++ b/lib/portability.h @@ -225,6 +225,10 @@ ssize_t getline(char **lineptr, size_t *n, FILE *stream); #define O_NOFOLLOW 0 #endif +#ifndef O_NOATIME +#define O_NOATIME 01000000 +#endif + #ifndef O_CLOEXEC #define O_CLOEXEC 02000000 #endif @@ -247,24 +251,3 @@ pid_t xfork(void); //#define strncpy(...) @@strncpyisbadmmkay@@ //#define strncat(...) @@strncatisbadmmkay@@ -#if CFG_TOYBOX_SELINUX -#include -#else -#define is_selinux_enabled() 0 -int getcon(void* con); -#endif - -#if CFG_TOYBOX_SMACK -#include -#include -#include -#else -#define smack_new_label_from_path(...) (-1) -#define smack_set_label_for_path(...) (-1) -#define smack_set_label_for_self(...) (-1) -#define XATTR_NAME_SMACK "" -#define SMACK_LABEL_LEN (1) /* for just ? */ - -ssize_t fgetxattr (int fd, char *name, void *value, size_t size); -#endif - diff --git a/toys/posix/ls.c b/toys/posix/ls.c index 35d1034a..ae0466bf 100644 --- a/toys/posix/ls.c +++ b/toys/posix/ls.c @@ -5,13 +5,13 @@ * * See http://opengroup.org/onlinepubs/9699919799/utilities/ls.html -USE_LS(NEWTOY(ls, USE_LS_COLOR("(color):;")USE_LS_Z("Z")"goACFHLRSacdfiklmnpqrstux1[-Cxm1][-Cxml][-Cxmo][-Cxmg][-cu][-ftS][-HL]", TOYFLAG_BIN|TOYFLAG_LOCALE)) +USE_LS(NEWTOY(ls, USE_LS_COLOR("(color):;")"ZgoACFHLRSacdfiklmnpqrstux1[-Cxm1][-Cxml][-Cxmo][-Cxmg][-cu][-ftS][-HL]", TOYFLAG_BIN|TOYFLAG_LOCALE)) config LS bool "ls" default y help - usage: ls [-ACFHLRSacdfiklmnpqrstux1] [directory...] + usage: ls [-ACFHLRSZacdfiklmnpqrstux1] [directory...] list files what to show: @@ -22,6 +22,7 @@ config LS -u use access time for timestamps -A list all files but . and .. -H follow command line symlinks -L follow symlinks -R recursively list files in subdirs -F append /dir *exe @sym |FIFO + -Z security context output formats: -1 list one file per line -C columns (sorted vertically) @@ -32,15 +33,6 @@ config LS sorting (default is alphabetical): -f unsorted -r reverse -t timestamp -S size -config LS_Z - bool - default y - depends on LS && (TOYBOX_SELINUX || TOYBOX_SMACK) - help - usage: ls [-Z] - - -Z security context - config LS_COLOR bool "ls --color" default y @@ -55,6 +47,7 @@ config LS_COLOR #define FOR_ls #include "toys.h" +#include "lib/lsm.h" // test sst output (suid/sticky in ls flaglist) @@ -63,7 +56,7 @@ config LS_COLOR GLOBALS( char *color; - struct dirtree *files; + struct dirtree *files, *singledir; unsigned screen_width; int nl_title; @@ -129,44 +122,6 @@ static int numlen(long long ll) return snprintf(0, 0, "%llu", ll); } -// measure/print SELinux/smack security label. (If pad=0, just measure.) -static unsigned seclabel(struct dirtree *dt, int pad) -{ - if (CFG_TOYBOX_SELINUX) { - char* path = dirtree_path(dt, 0); - char* label = 0; - size_t len; - - lgetfilecon(path, &label); - if (!label) { - label = strdup("?"); - } - - len = strlen(label); - if (pad) printf(" %*s "+(pad>0), pad, label); - - free(label); - free(path); - return len; - } else if (CFG_TOYBOX_SMACK) { - int fd = openat(dirtree_parentfd(dt), dt->name, O_PATH|O_NOFOLLOW); - char buf[SMACK_LABEL_LEN+1]; - ssize_t len = 1; - - strcpy(buf, "?"); - if (fd != -1) { - len = fgetxattr(fd, XATTR_NAME_SMACK, pad?buf:0, pad?SMACK_LABEL_LEN:0); - close(fd); - - if (len<1 || len>SMACK_LABEL_LEN) len = 0; - else buf[len] = 0; - } - if (pad) printf(" %*s "+(pad>0), pad, buf); - - return len; - } -} - // Figure out size of printable entry fields for display indent/wrap static void entrylen(struct dirtree *dt, unsigned *len) @@ -192,7 +147,7 @@ static void entrylen(struct dirtree *dt, unsigned *len) } len[6] = (flags & FLAG_s) ? numlen(st->st_blocks) : 0; - len[7] = (CFG_LS_Z && (flags & FLAG_Z)) ? seclabel(dt, 0) : 0; + len[7] = (flags & FLAG_Z) ? strwidth((char *)dt->extra) : 0; } static int compare(void *a, void *b) @@ -225,6 +180,32 @@ static int filter(struct dirtree *new) return 0; } + if (flags & FLAG_Z) { + if (!CFG_TOYBOX_LSM_NONE) { + // In theory we can just openat(O_PATH|O_NOFOLLOW) and getcontext() on + // that filehandle, but the kernel won't let us read this "metadata" + // unless we have permission to read the data, so we do these elaborate + // bug workarounds instead. + if (S_ISLNK(new->st.st_mode) && !(toys.optflags & FLAG_L)) { + char *path; + + // Wouldn't it be nice if the lsm functions worked like openat(), + // fchmodat(), mknodat(), readlinkat()... but no, this is 1990's tech. + path = dirtree_path(new, 0); + lsm_lget_context(path, (char **)&new->extra); + free(path); + } else { + // Why O_NONBLOCK? No idea. Why not O_PATH|O_NOFOLLOW? Because reasons. + int fd = openat(dirtree_parentfd(new), new->name, + O_RDONLY|O_NONBLOCK|O_NOATIME); + + if (fd != -1) lsm_fget_context(fd, (char **)&new->extra); + close(fd); + } + } + if (CFG_TOYBOX_LSM_NONE || !new->extra) new->extra = (long)xstrdup("?"); + } + if (flags & FLAG_u) new->st.st_mtime = new->st.st_atime; if (flags & FLAG_c) new->st.st_mtime = new->st.st_ctime; if (flags & FLAG_k) new->st.st_blocks = (new->st.st_blocks + 1) / 2; @@ -303,18 +284,19 @@ static void listfiles(int dirfd, struct dirtree *indir) memset(totals, 0, sizeof(totals)); - // Silently descend into single directory listed by itself on command line. - // In this case only show dirname/total header when given -R. + // Top level directory was already populated by main() if (!indir->parent) { - if (!(dt = indir->child)) return; + // Silently descend into single directory listed by itself on command line. + // In this case only show dirname/total header when given -R. + dt = indir->child; if (S_ISDIR(dt->st.st_mode) && !dt->next && !(flags & FLAG_d)) { - dt->extra = 1; - listfiles(open(dt->name, 0), dt); + listfiles(open(dt->name, 0), TT.singledir = dt); return; } } else { // Read directory contents. We dup() the fd because this will close it. + // This reads/saves contents to display later, except for in "ls -1f" mode. indir->data = dup(dirfd); dirtree_recurse(indir, filter, DIRTREE_SYMFOLLOW*!!(flags&FLAG_L)); } @@ -329,7 +311,7 @@ static void listfiles(int dirfd, struct dirtree *indir) } // Label directory if not top of tree, or if -R - if (indir->parent && (!indir->extra || (flags & FLAG_R))) + if (indir->parent && (TT.singledir!=indir || (flags&FLAG_R))) { char *path = dirtree_path(indir, 0); @@ -350,7 +332,7 @@ static void listfiles(int dirfd, struct dirtree *indir) blocks += sort[ul]->st.st_blocks; } totpad = totals[1]+!!totals[1]+totals[6]+!!totals[6]+totals[7]+!!totals[7]; - if (flags & (FLAG_l|FLAG_o|FLAG_n|FLAG_g|FLAG_s) && indir->parent) + if ((flags&(FLAG_l|FLAG_o|FLAG_n|FLAG_g|FLAG_s)) && indir->parent) xprintf("total %llu\n", blocks); } @@ -442,7 +424,8 @@ static void listfiles(int dirfd, struct dirtree *indir) printf("%s% *ld %s%s%s%s", perm, totals[2]+1, (long)st->st_nlink, usr, upad, grp, grpad); - if (CFG_LS_Z && (flags & FLAG_Z)) seclabel(sort[next], -(int)totals[7]); + if (flags & FLAG_Z) + printf("%*s ", -(int)totals[7], (char *)sort[next]->extra); if (S_ISCHR(st->st_mode) || S_ISBLK(st->st_mode)) printf("% *d,% 4d", totals[5]-4, major(st->st_rdev),minor(st->st_rdev)); @@ -451,7 +434,8 @@ static void listfiles(int dirfd, struct dirtree *indir) tm = localtime(&(st->st_mtime)); strftime(thyme, sizeof(thyme), "%F %H:%M", tm); xprintf(" %s ", thyme); - } else if (CFG_LS_Z && (flags & FLAG_Z)) seclabel(sort[next], totals[7]); + } else if (flags & FLAG_Z) + printf("%*s ", (int)totals[7], (char *)sort[next]->extra); if (flags & FLAG_color) { color = color_from_mode(st->st_mode); @@ -493,11 +477,10 @@ static void listfiles(int dirfd, struct dirtree *indir) // Free directory entries, recursing first if necessary. for (ul = 0; ulst.st_mode) - || !dirtree_notdotdot(sort[ul])) continue; + if ((flags & FLAG_d) || !S_ISDIR(sort[ul]->st.st_mode)) continue; // Recurse into dirs if at top of the tree or given -R - if (!indir->parent || (flags & FLAG_R)) + if (!indir->parent || ((flags&FLAG_R) && !dirtree_notdotdot(sort[ul]))) listfiles(openat(dirfd, sort[ul]->name, 0), sort[ul]); } free(sort); -- cgit v1.2.3