Hi,
I've just shot myself in the foot after /etc/doas.conf tweaking. This
patch adds a failsafe "permit :wheel" rule in case of syntax error. Is
this safe enough? Should it be done elsewhere (with some kind of
visudo)?
Index: doas.c
===================================================================
RCS file: /cvs/src/usr.bin/doas/doas.c,v
retrieving revision 1.14
diff -u -p -u -r1.14 doas.c
--- doas.c 20 Jul 2015 01:04:37 -0000 1.14
+++ doas.c 20 Jul 2015 12:16:11 -0000
@@ -138,12 +138,13 @@ permit(uid_t uid, gid_t *groups, int ngr
return (*lastr)->action == PERMIT;
}
-static void
+static int
parseconfig(const char *filename)
{
extern FILE *yyfp;
extern int yyparse(void);
struct stat sb;
+ int ret;
yyfp = fopen(filename, "r");
if (!yyfp) {
@@ -158,8 +159,9 @@ parseconfig(const char *filename)
if (sb.st_uid != 0)
errx(1, "%s is not owned by root", filename);
- yyparse();
+ ret = yyparse();
fclose(yyfp);
+ return ret;
}
static int
@@ -201,7 +203,7 @@ copyenv(const char **oldenvp, struct rul
int ei;
int nsafe, nbad;
int nextras = 0;
-
+
nbad = arraylen(badset);
if ((rule->options & KEEPENV) && !rule->envlist) {
size_t i, ii;
@@ -280,8 +282,18 @@ main(int argc, char **argv, char **envp)
int ngroups;
int i, ch;
int sflag = 0;
+ const char *safeident = ":wheel";
- parseconfig("/etc/doas.conf");
+ if (parseconfig("/etc/doas.conf") != 0) {
+ fprintf(stderr, "using failsafe rule\n");
+ if (!(rules = reallocarray(rules, 1, sizeof(*rules))))
+ errx(1, "can't allocate rules");
+ if (!(rules[0] = calloc(1, sizeof(struct rule))))
+ errx(1, "can't allocate rule");
+ rules[0]->action = PERMIT;
+ rules[0]->ident = safeident;
+ nrules = 1;
+ }
while ((ch = getopt(argc, argv, "su:")) != -1) {
switch (ch) {
Index: parse.y
===================================================================
RCS file: /cvs/src/usr.bin/doas/parse.y,v
retrieving revision 1.6
diff -u -p -u -r1.6 parse.y
--- parse.y 19 Jul 2015 22:11:41 -0000 1.6
+++ parse.y 20 Jul 2015 12:16:11 -0000
@@ -149,7 +149,7 @@ yyerror(const char *fmt, ...)
va_list va;
va_start(va, fmt);
- verrx(1, fmt, va);
+ vwarnx(fmt, va);
}
struct keyword {
--
Manuel Giraud
