util: be more picky when validating hostnames

[elogind.git] / src / shared / util.c

diff --git a/src/shared/util.c b/src/shared/util.c
index f94abbcc02502f442efd6699d934231a3fca1cf9..bc6e035c60d756ee7a06095ffe59b259114c4bcb 100644 (file)
--- a/src/shared/util.c
+++ b/src/shared/util.c
@@ -3773,13 +3773,27 @@ static bool hostname_valid_char(char c) {
 
 bool hostname_is_valid(const char *s) {
         const char *p;
+        bool dot;
 
         if (isempty(s))
                 return false;
 
-        for (p = s; *p; p++)
-                if (!hostname_valid_char(*p))
-                        return false;
+        for (p = s, dot = true; *p; p++) {
+                if (*p == '.') {
+                        if (dot)
+                                return false;
+
+                        dot = true;
+                } else {
+                        if (!hostname_valid_char(*p))
+                                return false;
+
+                        dot = false;
+                }
+        }
+
+        if (dot)
+                return false;
 
         if (p-s > HOST_NAME_MAX)
                 return false;
@@ -4190,6 +4204,23 @@ char* uid_to_name(uid_t uid) {
         return r;
 }
 
+char* gid_to_name(gid_t gid) {
+        struct group *p;
+        char *r;
+
+        if (gid == 0)
+                return strdup("root");
+
+        p = getgrgid(gid);
+        if (p)
+                return strdup(p->gr_name);
+
+        if (asprintf(&r, "%lu", (unsigned long) gid) < 0)
+                return NULL;
+
+        return r;
+}
+
 int get_group_creds(const char **groupname, gid_t *gid) {
         struct group *g;
         gid_t id;
@@ -4228,14 +4259,10 @@ int get_group_creds(const char **groupname, gid_t *gid) {
         return 0;
 }
 
-int in_group(const char *name) {
-        gid_t gid, *gids;
+int in_gid(gid_t gid) {
+        gid_t *gids;
         int ngroups_max, r, i;
 
-        r = get_group_creds(&name, &gid);
-        if (r < 0)
-                return r;
-
         if (getgid() == gid)
                 return 1;
 
@@ -4258,6 +4285,17 @@ int in_group(const char *name) {
         return 0;
 }
 
+int in_group(const char *name) {
+        int r;
+        gid_t gid;
+
+        r = get_group_creds(&name, &gid);
+        if (r < 0)
+                return r;
+
+        return in_gid(gid);
+}
+
 int glob_exists(const char *path) {
         glob_t g;
         int r, k;
@@ -5553,7 +5591,6 @@ int on_ac_power(void) {
         for (;;) {
                 struct dirent *de;
                 union dirent_storage buf;
-                _cleanup_free_ char *p = NULL;
                 _cleanup_close_ int fd = -1, device = -1;
                 char contents[6];
                 ssize_t n;
@@ -5797,3 +5834,22 @@ char *strextend(char **x, ...) {
 
         return r + l;
 }
+
+char *strrep(const char *s, unsigned n) {
+        size_t l;
+        char *r, *p;
+        unsigned i;
+
+        assert(s);
+
+        l = strlen(s);
+        p = r = malloc(l * n + 1);
+        if (!r)
+                return NULL;
+
+        for (i = 0; i < n; i++)
+                p = stpcpy(p, s);
+
+        *p = 0;
+        return r;
+}