From af92863ebbfc040909b6dbb89b887cecd3371508 Mon Sep 17 00:00:00 2001
From: default <nobody@localhost>
Date: Tue, 12 Nov 2024 05:38:55 +0100
Subject: [PATCH] Added new proxy authorization by token.

---
 data.c | 22 ++++++++++++++++++++--
 html.c | 39 ++++++++++++++++++++++++++++-----------
 snac.h |  2 +-
 3 files changed, 49 insertions(+), 14 deletions(-)

diff --git a/data.c b/data.c
index c119360..d42f9c8 100644
--- a/data.c
+++ b/data.c
@@ -12,6 +12,7 @@
 #include "xs_regex.h"
 #include "xs_match.h"
 #include "xs_unicode.h"
+#include "xs_random.h"
 
 #include "snac.h"
 
@@ -164,6 +165,23 @@ int srv_open(const char *basedir, int auto_upgrade)
         write_default_css();
     }
 
+    /* if proxy_media is set but there is no token seed, create one */
+    if (xs_is_true(xs_dict_get(srv_config, "proxy_media")) &&
+        xs_is_null(xs_dict_get(srv_config, "proxy_token_seed"))) {
+        char rnd[16];
+        xs_rnd_buf(rnd, sizeof(rnd));
+        xs *pts = xs_hex_enc(rnd, sizeof(rnd));
+
+        xs_dict_set(srv_config, "proxy_token_seed", pts);
+
+        if ((f = fopen(cfg_file, "w")) != NULL) {
+            xs_json_dump(srv_config, 4, f);
+            fclose(f);
+
+            srv_log(xs_fmt("Created proxy_token_seed"));
+        }
+    }
+
     return ret;
 }
 
@@ -3652,13 +3670,13 @@ t_announcement *announcement(const double after)
 }
 
 
-xs_str *make_url(const char *href, const char *proxy)
+xs_str *make_url(const char *href, const char *proxy, int by_token)
 /* makes an URL, possibly including proxying */
 {
     xs_str *url = NULL;
 
     if (proxy && !xs_startswith(href, srv_baseurl)) {
-        xs *p = xs_str_cat(xs_dup(proxy), "/proxy/");
+        xs *p = xs_str_cat(xs_dup(proxy), "/x/");
         url = xs_replace(href, "https:/" "/", p);
     }
     else
diff --git a/html.c b/html.c
index dbe8ae2..ce4c0a8 100644
--- a/html.c
+++ b/html.c
@@ -70,7 +70,7 @@ xs_str *replace_shortnames(xs_str *s, const xs_list *tag, int ems, const char *p
 
                 if (n && i) {
                     const char *u = xs_dict_get(i, "url");
-                    xs *url = make_url(u, proxy);
+                    xs *url = make_url(u, proxy, 0);
 
                     xs_html *img = xs_html_sctag("img",
                         xs_html_attr("loading", "lazy"),
@@ -122,7 +122,7 @@ xs_html *html_actor_icon(snac *user, xs_dict *actor, const char *date,
             v = xs_list_get(v, 0);
 
         if ((v = xs_dict_get(v, "url")) != NULL)
-            avatar = make_url(v, proxy);
+            avatar = make_url(v, proxy, 0);
     }
 
     if (avatar == NULL)
@@ -1973,7 +1973,7 @@ xs_html *html_entry(snac *user, xs_dict *msg, int read_only,
             if (content && xs_str_in(content, o_href) != -1)
                 continue;
 
-            xs *href = make_url(o_href, proxy);
+            xs *href = make_url(o_href, proxy, 0);
 
             if (xs_startswith(type, "image/") || strcmp(type, "Image") == 0) {
                 xs_html_add(content_attachments,
@@ -2788,7 +2788,7 @@ int html_get_handler(const xs_dict *req, const char *q_path,
     const char *p_path;
     int cache = 1;
     int save = 1;
-    const char *proxy = NULL;
+    int proxy = 0;
     const char *v;
 
     xs *l = xs_split_n(q_path, "/", 2);
@@ -2816,7 +2816,7 @@ int html_get_handler(const xs_dict *req, const char *q_path,
     }
 
     if (xs_is_true(xs_dict_get(srv_config, "proxy_media")))
-        proxy = snac.actor;
+        proxy = 1;
 
     /* return the RSS if requested by Accept header */
     if (accept != NULL) {
@@ -3194,19 +3194,36 @@ int html_get_handler(const xs_dict *req, const char *q_path,
         snac_debug(&snac, 1, xs_fmt("serving RSS"));
     }
     else
-    if (xs_startswith(p_path, "proxy/") && proxy) { /** remote media by proxy **/
-        if (!login(&snac, req)) {
-            *body  = xs_dup(uid);
-            status = HTTP_STATUS_UNAUTHORIZED;
+    if (proxy && (xs_startswith(p_path, "x/") || xs_startswith(p_path, "y/"))) { /** remote media by proxy **/
+        xs *proxy_prefix = NULL;
+
+        if (xs_startswith(p_path, "x/")) {
+            /* proxy usage authorized by http basic auth */
+            if (login(&snac, req))
+                proxy_prefix = xs_str_new("x/");
+            else {
+                *body  = xs_dup(uid);
+                status = HTTP_STATUS_UNAUTHORIZED;
+            }
         }
         else {
+            /* proxy usage authorized by proxy_token */
+            xs *tks = xs_fmt("%s:%s", xs_dict_get(srv_config, "proxy_token_seed"), snac.actor);
+            xs *tk = xs_md5_hex(tks, strlen(tks));
+            xs *p = xs_fmt("y/%s/", tk);
+
+            if (xs_startswith(p_path, p))
+                proxy_prefix = xs_dup(p);
+        }
+
+        if (proxy_prefix) {
             /* pick the raw path (including optional ? arguments) */
             const char *raw_path = xs_dict_get(req, "raw_path");
 
             /* skip to where the proxy/ string starts */
-            raw_path += xs_str_in(raw_path, "proxy/");
+            raw_path += xs_str_in(raw_path, proxy_prefix);
 
-            xs *url = xs_replace(raw_path, "proxy/", "https:/" "/");
+            xs *url = xs_replace(raw_path, proxy_prefix, "https:/" "/");
             xs *hdrs = xs_dict_new();
 
             hdrs = xs_dict_append(hdrs, "user-agent", USER_AGENT);
diff --git a/snac.h b/snac.h
index d893863..9658fc9 100644
--- a/snac.h
+++ b/snac.h
@@ -411,4 +411,4 @@ typedef struct {
 } t_announcement;
 t_announcement *announcement(double after);
 
-xs_str *make_url(const char *href, const char *proxy);
+xs_str *make_url(const char *href, const char *proxy, int by_token);