[hackers] [quark] Send absolute path when redirecting || Laslo Hunhold

[git]

commit d598da3d52413b20cffe2c7f03c885ffdcca2818
Author:     Laslo Hunhold <d...@frign.de>
AuthorDate: Fri Jul 7 13:33:43 2017 +0200
Commit:     Laslo Hunhold <d...@frign.de>
CommitDate: Fri Jul 7 13:33:43 2017 +0200

    Send absolute path when redirecting
    
    The logic is a little more complicated, but we need it for some future
    changes.

diff --git a/quark.c b/quark.c
index 84b358b..af6e536 100644
--- a/quark.c
+++ b/quark.c
@@ -36,12 +36,14 @@ char *argv0;
 #define TIMESTAMP_LEN 30
 
 enum req_field {
+       REQ_HOST,
        REQ_RANGE,
        REQ_MOD,
        NUM_REQ_FIELDS,
 };
 
 static char *req_field_str[] = {
+       [REQ_HOST]    = "Host",
        [REQ_RANGE]   = "Range",
        [REQ_MOD]     = "If-Modified-Since",
 };
@@ -542,10 +544,12 @@ squash:
 static enum status
 sendresponse(int fd, struct request *r)
 {
+       struct in6_addr res;
        struct stat st;
        struct tm tm;
        size_t len, i;
        off_t lower, upper;
+       int hasport, ipv6host;
        static char realtarget[PATH_MAX], tmptarget[PATH_MAX], t[TIMESTAMP_LEN];
        char *p, *q, *mime;
        const char *err;
@@ -580,18 +584,31 @@ sendresponse(int fd, struct request *r)
 
        /* redirect if targets differ */
        if (strcmp(r->target, realtarget)) {
+               /* do we need to add a port to the Location? */
+               hasport = strcmp(port, "80");
+
+               /* RFC 2732 specifies to use brackets for IPv6-addresses in
+                * URLs, so we need to check if our host is one and honor that
+                * later when we fill the "Location"-field */
+               ipv6host = inet_pton(AF_INET6, r->field[REQ_HOST][0] ?
+                                    r->field[REQ_HOST] : host, &res);
+
                /* encode realtarget */
                encode(realtarget, tmptarget);
 
+               /* send redirection header */
                if (dprintf(fd,
                            "HTTP/1.1 %d %s\r\n"
                            "Date: %s\r\n"
                            "Connection: close\r\n"
-                           "Location: %s\r\n"
+                           "Location: http://%s%s%s%s%s%s\r\n";
                            "\r\n",
                            S_MOVED_PERMANENTLY,
                            status_str[S_MOVED_PERMANENTLY],
-                           timestamp(time(NULL), t), tmptarget) < 0) {
+                           timestamp(time(NULL), t), ipv6host ? "[" : "",
+                           r->field[REQ_HOST][0] ? r->field[REQ_HOST] : host,
+                           ipv6host ? "]" : "", hasport ? ":" : "",
+                           hasport ? port : "", tmptarget) < 0) {
                        return S_REQUEST_TIMEOUT;
                }