upstream: move authorized_keys option parsing helpsers to misc.c

and make them public; ok markus@

OpenBSD-Commit-ID: c18bcb2a687227b3478377c981c2d56af2638ea2

1 files changed, 73 insertions, 1 deletions

diff --git a/misc.c b/misc.c
index d5e44da77..88833d7ff 100644
--- a/misc.c
+++ b/misc.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: misc.c,v 1.141 2019/09/03 08:29:58 djm Exp $ */
+/* $OpenBSD: misc.c,v 1.142 2019/09/03 08:32:11 djm Exp $ */
 /*
  * Copyright (c) 2000 Markus Friedl.  All rights reserved.
  * Copyright (c) 2005,2006 Damien Miller.  All rights reserved.
@@ -2137,3 +2137,75 @@ skip_space(char **cpp)
                 ;
         *cpp = cp;
 }
+
+/* authorized_key-style options parsing helpers */
+
+/*
+ * Match flag 'opt' in *optsp, and if allow_negate is set then also match
+ * 'no-opt'. Returns -1 if option not matched, 1 if option matches or 0
+ * if negated option matches.
+ * If the option or negated option matches, then *optsp is updated to
+ * point to the first character after the option.
+ */
+int
+opt_flag(const char *opt, int allow_negate, const char **optsp)
+{
+        size_t opt_len = strlen(opt);
+        const char *opts = *optsp;
+        int negate = 0;
+
+        if (allow_negate && strncasecmp(opts, "no-", 3) == 0) {
+                opts += 3;
+                negate = 1;
+        }
+        if (strncasecmp(opts, opt, opt_len) == 0) {
+                *optsp = opts + opt_len;
+                return negate ? 0 : 1;
+        }
+        return -1;
+}
+
+char *
+opt_dequote(const char **sp, const char **errstrp)
+{
+        const char *s = *sp;
+        char *ret;
+        size_t i;
+
+        *errstrp = NULL;
+        if (*s != '"') {
+                *errstrp = "missing start quote";
+                return NULL;
+        }
+        s++;
+        if ((ret = malloc(strlen((s)) + 1)) == NULL) {
+                *errstrp = "memory allocation failed";
+                return NULL;
+        }
+        for (i = 0; *s != '\0' && *s != '"';) {
+                if (s[0] == '\\' && s[1] == '"')
+                        s++;
+                ret[i++] = *s++;
+        }
+        if (*s == '\0') {
+                *errstrp = "missing end quote";
+                free(ret);
+                return NULL;
+        }
+        ret[i] = '\0';
+        s++;
+        *sp = s;
+        return ret;
+}
+
+int
+opt_match(const char **opts, const char *term)
+{
+        if (strncasecmp((*opts), term, strlen(term)) == 0 &&
+            (*opts)[strlen(term)] == '=') {
+                *opts += strlen(term) + 1;
+                return 1;
+        }
+        return 0;
+}
+