X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Flabel.c;h=3df7e55ba41316c2d44959dba238f2f1f2513354;hp=21e7ee6ac8194ec11b4af4c5f6a960d20ecf20c9;hb=3c20189a722e6f2eec12c57c3bf3567533073c66;hpb=d6c9574fb558d9e304699b1cc7522c3b133adfc9 diff --git a/src/label.c b/src/label.c index 21e7ee6ac..3df7e55ba 100644 --- a/src/label.c +++ b/src/label.c @@ -22,6 +22,9 @@ #include #include #include +#include +#include +#include #include "label.h" #include "util.h" @@ -32,38 +35,18 @@ static struct selabel_handle *label_hnd = NULL; +static int use_selinux_cached = -1; + static inline bool use_selinux(void) { - static int use_selinux_ind = -1; - if (use_selinux_ind < 0) - use_selinux_ind = is_selinux_enabled() > 0; + if (use_selinux_cached < 0) + use_selinux_cached = is_selinux_enabled() > 0; - return use_selinux_ind; + return use_selinux_cached; } -static int label_get_file_label_from_path( - const char *label, - const char *path, - const char *class, - security_context_t *fcon) { - - security_context_t dir_con = NULL; - security_class_t sclass; - int r = 0; - - r = getfilecon(path, &dir_con); - if (r >= 0) { - r = -1; - errno = EINVAL; - - if ((sclass = string_to_security_class(class)) != 0) - r = security_compute_create((security_context_t) label, dir_con, sclass, fcon); - } - if (r < 0) - r = -errno; - - freecon(dir_con); - return r; +void label_retest_selinux(void) { + use_selinux_cached = -1; } #endif @@ -72,22 +55,42 @@ int label_init(void) { int r = 0; #ifdef HAVE_SELINUX + usec_t before_timestamp, after_timestamp; + struct mallinfo before_mallinfo, after_mallinfo; if (!use_selinux()) return 0; + if (label_hnd) + return 0; + + before_mallinfo = mallinfo(); + before_timestamp = now(CLOCK_MONOTONIC); + label_hnd = selabel_open(SELABEL_CTX_FILE, NULL, 0); if (!label_hnd) { log_full(security_getenforce() == 1 ? LOG_ERR : LOG_DEBUG, "Failed to initialize SELinux context: %m"); - r = (security_getenforce() == 1) ? -errno : 0; + r = security_getenforce() == 1 ? -errno : 0; + } else { + char timespan[FORMAT_TIMESPAN_MAX]; + int l; + + after_timestamp = now(CLOCK_MONOTONIC); + after_mallinfo = mallinfo(); + + l = after_mallinfo.uordblks > before_mallinfo.uordblks ? after_mallinfo.uordblks - before_mallinfo.uordblks : 0; + + log_info("Successfully loaded SELinux database in %s, size on heap is %iK.", + format_timespan(timespan, sizeof(timespan), after_timestamp - before_timestamp), + (l+1023)/1024); } #endif return r; } -int label_fix(const char *path) { +int label_fix(const char *path, bool ignore_enoent) { int r = 0; #ifdef HAVE_SELINUX @@ -101,15 +104,28 @@ int label_fix(const char *path) { if (r == 0) { r = selabel_lookup_raw(label_hnd, &fcon, path, st.st_mode); + /* If there's no label to set, then exit without warning */ + if (r < 0 && errno == ENOENT) + return 0; + if (r == 0) { r = setfilecon(path, fcon); freecon(fcon); + + /* If the FS doesn't support labels, then exit without warning */ + if (r < 0 && errno == ENOTSUP) + return 0; } } + if (r < 0) { + /* Ignore ENOENT in some cases */ + if (ignore_enoent && errno == ENOENT) + return 0; + log_full(security_getenforce() == 1 ? LOG_ERR : LOG_DEBUG, "Unable to fix label of %s: %m", path); - r = (security_getenforce() == 1) ? -errno : 0; + r = security_getenforce() == 1 ? -errno : 0; } #endif @@ -124,7 +140,7 @@ void label_finish(void) { #endif } -int label_get_socket_label_from_exe(const char *exe, char **label) { +int label_get_create_label_from_exe(const char *exe, char **label) { int r = 0; @@ -161,18 +177,51 @@ fail: return r; } -int label_fifofile_set(const char *label, const char *path) { +int label_fifofile_set(const char *path) { + int r = 0; + +#ifdef HAVE_SELINUX + security_context_t filecon = NULL; + + if (!use_selinux() || !label_hnd) + return 0; + + r = selabel_lookup_raw(label_hnd, &filecon, path, S_IFIFO); + if (r < 0) + r = -errno; + else if (r == 0) { + r = setfscreatecon(filecon); + if (r < 0) { + log_error("Failed to set SELinux file context on %s: %m", path); + r = -errno; + } + + freecon(filecon); + } + + if (r < 0 && security_getenforce() == 0) + r = 0; +#endif + + return r; +} + +int label_symlinkfile_set(const char *path) { int r = 0; #ifdef HAVE_SELINUX security_context_t filecon = NULL; - if (!use_selinux() || !label) + if (!use_selinux() || !label_hnd) return 0; - if (((r = label_get_file_label_from_path(label, path, "fifo_file", &filecon)) == 0)) { - if ((r = setfscreatecon(filecon)) < 0) { - log_error("Failed to set SELinux file context (%s) on %s: %m", label, path); + r = selabel_lookup_raw(label_hnd, &filecon, path, S_IFLNK); + if (r < 0) + r = -errno; + else if (r == 0) { + r = setfscreatecon(filecon); + if (r < 0) { + log_error("Failed to set SELinux file context on %s: %m", path); r = -errno; } @@ -234,9 +283,7 @@ void label_free(const char *label) { #endif } -int label_mkdir( - const char *path, - mode_t mode) { +int label_mkdir(const char *path, mode_t mode) { /* Creates a directory and labels it according to the SELinux policy */ @@ -244,48 +291,123 @@ int label_mkdir( int r; security_context_t fcon = NULL; - if (use_selinux() && label_hnd) { + if (!use_selinux() || label_hnd) + goto skipped; - if (path[0] == '/') - r = selabel_lookup_raw(label_hnd, &fcon, path, mode); - else { - char *cwd = NULL, *newpath = NULL; + if (path_is_absolute(path)) + r = selabel_lookup_raw(label_hnd, &fcon, path, S_IFDIR); + else { + char *newpath; - cwd = get_current_dir_name(); + newpath = path_make_absolute_cwd(path); + if (!newpath) + return -ENOMEM; - if (cwd || asprintf(&newpath, "%s/%s", cwd, path) < 0) { - free(cwd); - return -errno; - } + r = selabel_lookup_raw(label_hnd, &fcon, newpath, S_IFDIR); + free(newpath); + } - r = selabel_lookup_raw(label_hnd, &fcon, newpath, mode); - free(cwd); - free(newpath); - } + if (r == 0) + r = setfscreatecon(fcon); - if (r == 0) - r = setfscreatecon(fcon); + if (r < 0 && errno != ENOENT) { + log_error("Failed to set security context %s for %s: %m", fcon, path); - if (r < 0 && errno != ENOENT) { - log_error("Failed to set security context %s for %s: %m", fcon, path); + if (security_getenforce() == 1) { r = -errno; - - if (security_getenforce() == 1) - goto finish; + goto finish; } } - if ((r = mkdir(path, mode)) < 0) + r = mkdir(path, mode); + if (r < 0) r = -errno; finish: - if (use_selinux() && label_hnd) { - setfscreatecon(NULL); - freecon(fcon); + setfscreatecon(NULL); + freecon(fcon); + + return r; + +skipped: +#endif + return mkdir(path, mode) < 0 ? -errno : 0; +} + +int label_bind(int fd, const struct sockaddr *addr, socklen_t addrlen) { + + /* Binds a socket and label its file system object according to the SELinux policy */ + +#ifdef HAVE_SELINUX + int r; + security_context_t fcon = NULL; + const struct sockaddr_un *un; + char *path = NULL; + + assert(fd >= 0); + assert(addr); + assert(addrlen >= sizeof(sa_family_t)); + + if (!use_selinux() || !label_hnd) + goto skipped; + + /* Filter out non-local sockets */ + if (addr->sa_family != AF_UNIX) + goto skipped; + + /* Filter out anonymous sockets */ + if (addrlen < sizeof(sa_family_t) + 1) + goto skipped; + + /* Filter out abstract namespace sockets */ + un = (const struct sockaddr_un*) addr; + if (un->sun_path[0] == 0) + goto skipped; + + path = strndup(un->sun_path, addrlen - offsetof(struct sockaddr_un, sun_path)); + if (!path) + return -ENOMEM; + + if (path_is_absolute(path)) + r = selabel_lookup_raw(label_hnd, &fcon, path, S_IFSOCK); + else { + char *newpath; + + newpath = path_make_absolute_cwd(path); + + if (!newpath) { + free(path); + return -ENOMEM; + } + + r = selabel_lookup_raw(label_hnd, &fcon, newpath, S_IFSOCK); + free(newpath); } + if (r == 0) + r = setfscreatecon(fcon); + + if (r < 0 && errno != ENOENT) { + log_error("Failed to set security context %s for %s: %m", fcon, path); + + if (security_getenforce() == 1) { + r = -errno; + goto finish; + } + } + + r = bind(fd, addr, addrlen); + if (r < 0) + r = -errno; + +finish: + setfscreatecon(NULL); + freecon(fcon); + free(path); + return r; -#else - return mkdir(path, mode); + +skipped: #endif + return bind(fd, addr, addrlen) < 0 ? -errno : 0; }