From: Zbigniew Jędrzejewski-Szmek <zbyszek@in.waw.pl>
Date: Sat, 18 Feb 2017 03:56:28 +0000 (-0500)
Subject: Tighten checking for variable validity
X-Git-Tag: v233.3~55
X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=commitdiff_plain;h=aec69f738f9d44afa89dbff2616edc6b5372900d;ds=sidebyside

Tighten checking for variable validity

In the future we might want to allow additional syntax (for example
"unset VAR". But let's check that the data we're getting does not contain
anything unexpected.
---

diff --git a/src/basic/fileio.c b/src/basic/fileio.c
index 94ebcbdc4..eadc8b7ea 100644
--- a/src/basic/fileio.c
+++ b/src/basic/fileio.c
@@ -586,14 +586,9 @@ fail:
         return r;
 }
 
-static int parse_env_file_push(
+static int check_utf8ness_and_warn(
                 const char *filename, unsigned line,
-                const char *key, char *value,
-                void *userdata,
-                int *n_pushed) {
-
-        const char *k;
-        va_list aq, *ap = userdata;
+                const char *key, char *value) {
 
         if (!utf8_is_valid(key)) {
                 _cleanup_free_ char *p = NULL;
@@ -611,6 +606,23 @@ static int parse_env_file_push(
                 return -EINVAL;
         }
 
+        return 0;
+}
+
+static int parse_env_file_push(
+                const char *filename, unsigned line,
+                const char *key, char *value,
+                void *userdata,
+                int *n_pushed) {
+
+        const char *k;
+        va_list aq, *ap = userdata;
+        int r;
+
+        r = check_utf8ness_and_warn(filename, line, key, value);
+        if (r < 0)
+                return r;
+
         va_copy(aq, *ap);
 
         while ((k = va_arg(aq, const char *))) {
@@ -663,27 +675,19 @@ static int load_env_file_push(
         char *p;
         int r;
 
-        if (!utf8_is_valid(key)) {
-                _cleanup_free_ char *t = utf8_escape_invalid(key);
-
-                log_error("%s:%u: invalid UTF-8 for key '%s', ignoring.", strna(filename), line, t);
-                return -EINVAL;
-        }
-
-        if (value && !utf8_is_valid(value)) {
-                _cleanup_free_ char *t = utf8_escape_invalid(value);
-
-                log_error("%s:%u: invalid UTF-8 value for key %s: '%s', ignoring.", strna(filename), line, key, t);
-                return -EINVAL;
-        }
+        r = check_utf8ness_and_warn(filename, line, key, value);
+        if (r < 0)
+                return r;
 
-        p = strjoin(key, "=", strempty(value));
+        p = strjoin(key, "=", value);
         if (!p)
                 return -ENOMEM;
 
-        r = strv_consume(m, p);
-        if (r < 0)
+        r = strv_env_replace(m, p);
+        if (r < 0) {
+                free(p);
                 return r;
+        }
 
         if (n_pushed)
                 (*n_pushed)++;
@@ -717,19 +721,9 @@ static int load_env_file_push_pairs(
         char ***m = userdata;
         int r;
 
-        if (!utf8_is_valid(key)) {
-                _cleanup_free_ char *t = utf8_escape_invalid(key);
-
-                log_error("%s:%u: invalid UTF-8 for key '%s', ignoring.", strna(filename), line, t);
-                return -EINVAL;
-        }
-
-        if (value && !utf8_is_valid(value)) {
-                _cleanup_free_ char *t = utf8_escape_invalid(value);
-
-                log_error("%s:%u: invalid UTF-8 value for key %s: '%s', ignoring.", strna(filename), line, key, t);
-                return -EINVAL;
-        }
+        r = check_utf8ness_and_warn(filename, line, key, value);
+        if (r < 0)
+                return r;
 
         r = strv_extend(m, key);
         if (r < 0)
@@ -768,6 +762,49 @@ int load_env_file_pairs(FILE *f, const char *fname, const char *newline, char **
         return 0;
 }
 
+static int merge_env_file_push(
+                const char *filename, unsigned line,
+                const char *key, char *value,
+                void *userdata,
+                int *n_pushed) {
+
+        char ***env = userdata;
+        char *expanded_value;
+
+        assert(env);
+
+        if (!value) {
+                log_error("%s:%u: invalid syntax (around \"%s\"), ignoring.", strna(filename), line, key);
+                return 0;
+        }
+
+        if (!env_name_is_valid(key)) {
+                log_error("%s:%u: invalid variable name \"%s\", ignoring.", strna(filename), line, key);
+                return 0;
+        }
+
+        expanded_value = replace_env(value, *env,
+                                     REPLACE_ENV_USE_ENVIRONMENT|REPLACE_ENV_ALLOW_BRACELESS);
+        if (!expanded_value)
+                return -ENOMEM;
+
+        free_and_replace(value, expanded_value);
+
+        return load_env_file_push(filename, line, key, value, env, n_pushed);
+}
+
+int merge_env_file(
+                char ***env,
+                FILE *f,
+                const char *fname) {
+
+        /* NOTE: this function supports braceful and braceless variable expansions,
+         * unlike other exported parsing functions.
+         */
+
+        return parse_env_file_internal(f, fname, NEWLINE, merge_env_file_push, env, NULL);
+}
+
 static void write_env_var(FILE *f, const char *v) {
         const char *p;