basicauth.[ch]: refactor to make basicauth_string() reusable

src/basicauth.c

@@ -26,35 +26,46 @@
 #include "conf.h"
 #include "base64.h"
 
+/*
+ * Create basic-auth token in buf.
+ * Returns strlen of token on success,
+ * -1 if user/pass missing
+ * 0 if user/pass too long
+ */
+ssize_t basicauth_string(const char *user, const char *pass,
+	char *buf, size_t bufsize)
+{
+	char tmp[256+2];
+	int l;
+	if (!user || !pass) return -1;
+	l = snprintf(tmp, sizeof tmp, "%s:%s", user, pass);
+	if (l < 0 || l >= (ssize_t) sizeof tmp) return 0;
+	if (bufsize < (BASE64ENC_BYTES((unsigned)l) + 1)) return 0;
+	base64enc(buf, tmp, l);
+	return BASE64ENC_BYTES(l);
+}
+
 /*
  * Add entry to the basicauth list
  */
 void basicauth_add (vector_t authlist,
 	const char *user, const char *pass)
 {
-	char tmp[256+2];
+	char b[BASE64ENC_BYTES((256+2)-1) + 1];
-	char b[BASE64ENC_BYTES((sizeof tmp)-1) + 1];
+	ssize_t ret;
-	int l;
-	size_t bl;
 
-        if (user == NULL || pass == NULL) {
+        ret = basicauth_string(user, pass, b, sizeof b);
+        if (ret == -1) {
                 log_message (LOG_WARNING,
                              "Illegal basicauth rule: missing user or pass");
                 return;
-        }
+        } else if (ret == 0) {
-
-        l = snprintf(tmp, sizeof tmp, "%s:%s", user, pass);
-
-        if(l >= (ssize_t) sizeof tmp) {
                 log_message (LOG_WARNING,
-                            "User / pass in basicauth rule too long");
+                             "User / pass in basicauth rule too long");
                 return;
         }
 
-        base64enc(b, tmp, l);
+        if (vector_append(authlist, b, ret + 1) == -ENOMEM) {
-        bl = BASE64ENC_BYTES(l) + 1;
-
-        if (vector_append(authlist, b, bl) == -ENOMEM) {
                 log_message (LOG_ERR,
                              "Unable to allocate memory in basicauth_add()");
                 return;

src/basicauth.h

@@ -21,8 +21,12 @@
 #ifndef TINYPROXY_BASICAUTH_H
 #define TINYPROXY_BASICAUTH_H
 
+#include <stddef.h>
 #include "vector.h"
 
+extern ssize_t basicauth_string(const char *user, const char *pass,
+	char *buf, size_t bufsize);
+
 extern void basicauth_add (vector_t authlist,
 	const char *user, const char *pass);