fix length computation in dn_expand

there are two possible points where the length is evaluated: either
the first 'compression' jump, or the null terminator if no jumps have
taken place yet. the previous code only measured the length of the
first component.

diff --git a/src/network/dn_expand.c b/src/network/dn_expand.c
index 72a80e82a6f98273c33573221315f62b1daa5903..f817d059ae9c43bdaecb7fdddbbedd740af613b3 100644 (file)
--- a/src/network/dn_expand.c
+++ b/src/network/dn_expand.c
@@ -6,7 +6,7 @@ int __dn_expand(const unsigned char *base, const unsigned char *end, const unsig
        const unsigned char *p = src;
        int len = -1, j;
        if (space > 256) space = 256;
-       if (p==end) return -1;
+       if (p==end || !*p) return -1;
        for (;;) {
                if (*p & 0xc0) {
                        if (p+1==end) return -1;
@@ -16,11 +16,13 @@ int __dn_expand(const unsigned char *base, const unsigned char *end, const unsig
                        p = base+j;
                } else if (*p) {
                        j = *p+1;
-                       if (len < 0) len = p+1-src;
                        if (j>=end-p || j>space) return -1;
                        while (--j) *dest++ = *p++;
                        *dest++ = *++p ? '.' : 0;
-               } else return len;
+               } else {
+                       if (len < 0) len = p+1-src;
+                       return len;
+               }
        }
 }