MINOR: proxy: move 'originalto' option to http_ext

Just like forwarded (7239) header and forwardfor header, move parsing,
logic and management of 'originalto' option into http_ext dedicated class.

We're only doing this to standardize proxy http options management.
Existing behavior remains untouched.
diff --git a/include/haproxy/http_ext-t.h b/include/haproxy/http_ext-t.h
index 65a105c..22f5633 100644
--- a/include/haproxy/http_ext-t.h
+++ b/include/haproxy/http_ext-t.h
@@ -120,4 +120,9 @@
 	uint8_t         mode;
 };
 
+struct http_ext_xot {
+	struct ist      hdr_name;   /* header to use - default: "x-original-to" */
+	struct net_addr except_net; /* don't forward x-original-to for this address. */
+};
+
 #endif /* !_HAPROXY_HTTPEXT_T_H */
diff --git a/include/haproxy/http_ext.h b/include/haproxy/http_ext.h
index 7f12830..63ecafb 100644
--- a/include/haproxy/http_ext.h
+++ b/include/haproxy/http_ext.h
@@ -31,15 +31,19 @@
 
 int http_handle_7239_header(struct stream *s, struct channel *req);
 int http_handle_xff_header(struct stream *s, struct channel *req);
+int http_handle_xot_header(struct stream *s, struct channel *req);
 
 void http_ext_7239_clean(struct http_ext_7239 *);
 void http_ext_xff_clean(struct http_ext_xff *);
+void http_ext_xot_clean(struct http_ext_xot *);
 
 void http_ext_7239_copy(struct http_ext_7239 *dest, const struct http_ext_7239 *orig);
 void http_ext_xff_copy(struct http_ext_xff *dest, const struct http_ext_xff *orig);
+void http_ext_xot_copy(struct http_ext_xot *dest, const struct http_ext_xot *orig);
 
 int proxy_http_parse_7239(char **args, int cur_arg, struct proxy *curproxy, const struct proxy *defpx, const char *file, int linenum);
 int proxy_http_compile_7239(struct proxy *curproxy);
 int proxy_http_parse_xff(char **args, int cur_arg, struct proxy *curproxy, const struct proxy *defpx, const char *file, int linenum);
+int proxy_http_parse_xot(char **args, int cur_arg, struct proxy *curproxy, const struct proxy *defpx, const char *file, int linenum);
 
 #endif /* !_HAPROXY_HTTPEXT_H */
diff --git a/include/haproxy/proxy-t.h b/include/haproxy/proxy-t.h
index 0f682ef..8391f9f 100644
--- a/include/haproxy/proxy-t.h
+++ b/include/haproxy/proxy-t.h
@@ -115,7 +115,7 @@
 #define PR_O_CONTSTATS	0x10000000	/* continuous counters */
 /* unused: 0x20000000 */
 #define PR_O_DISABLE404 0x40000000      /* Disable a server on a 404 response to a health-check */
-#define PR_O_ORGTO      0x80000000      /* insert x-original-to with destination address */
+#define PR_O_HTTP_XOT   0x80000000      /* insert x-original-to with destination address */
 
 /* bits for proxy->options2 */
 #define PR_O2_SPLIC_REQ	0x00000001      /* transfer requests using linux kernel's splice() */
@@ -273,6 +273,8 @@
 	struct http_ext_7239       fwd;
 	/* x-forward-for */
 	struct http_ext_xff        xff;
+	/* x-original-to */
+	struct http_ext_xot        xot;
 };
 
 struct proxy {
@@ -366,8 +368,6 @@
 	unsigned int fe_sps_lim;		/* limit on new sessions per second on the frontend */
 	unsigned int fullconn;			/* #conns on backend above which servers are used at full load */
 	unsigned int tot_fe_maxconn;		/* #maxconn of frontends linked to that backend, it is used to compute fullconn */
-	struct net_addr except_xot_net;         /* don't x-original-to for this address. */
-	struct ist orgto_hdr_name;			/* header to use - default: "x-original-to" */
 	struct ist server_id_hdr_name;                   /* the header to use to send the server id (name) */
 	int conn_retries;			/* maximum number of connect retries */
 	unsigned int retry_type;                /* Type of retry allowed */
diff --git a/src/cfgparse-listen.c b/src/cfgparse-listen.c
index 112fac3..20965c8 100644
--- a/src/cfgparse-listen.c
+++ b/src/cfgparse-listen.c
@@ -2278,68 +2278,9 @@
 				goto out;
 		}
 		else if (strcmp(args[1], "originalto") == 0) {
-			int cur_arg;
-
-			/* insert x-original-to field, but not for the IP address listed as an except.
-			 * set default options (ie: bitfield, header name, etc)
-			 */
-
-			curproxy->options |= PR_O_ORGTO;
-
-			istfree(&curproxy->orgto_hdr_name);
-			curproxy->orgto_hdr_name = istdup(ist(DEF_XORIGINALTO_HDR));
-			if (!isttest(curproxy->orgto_hdr_name))
-				goto alloc_error;
-			curproxy->except_xot_net.family = AF_UNSPEC;
-
-			/* loop to go through arguments - start at 2, since 0+1 = "option" "originalto" */
-			cur_arg = 2;
-			while (*(args[cur_arg])) {
-				if (strcmp(args[cur_arg], "except") == 0) {
-					unsigned char mask;
-					int i;
-
-					/* suboption except - needs additional argument for it */
-					if (*(args[cur_arg+1]) &&
-					    str2net(args[cur_arg+1], 1, &curproxy->except_xot_net.addr.v4.ip, &curproxy->except_xot_net.addr.v4.mask)) {
-						curproxy->except_xot_net.family = AF_INET;
-						curproxy->except_xot_net.addr.v4.ip.s_addr &= curproxy->except_xot_net.addr.v4.mask.s_addr;
-					}
-					else if (*(args[cur_arg+1]) &&
-						 str62net(args[cur_arg+1], &curproxy->except_xot_net.addr.v6.ip, &mask)) {
-						curproxy->except_xot_net.family = AF_INET6;
-						len2mask6(mask, &curproxy->except_xot_net.addr.v6.mask);
-						for (i = 0; i < 16; i++)
-							curproxy->except_xot_net.addr.v6.ip.s6_addr[i] &= curproxy->except_xot_net.addr.v6.mask.s6_addr[i];
-					}
-					else {
-						ha_alert("parsing [%s:%d] : '%s %s %s' expects <address>[/mask] as argument.\n",
-							 file, linenum, args[0], args[1], args[cur_arg]);
-						err_code |= ERR_ALERT | ERR_FATAL;
-						goto out;
-					}
-					cur_arg += 2;
-				} else if (strcmp(args[cur_arg], "header") == 0) {
-					/* suboption header - needs additional argument for it */
-					if (*(args[cur_arg+1]) == 0) {
-						ha_alert("parsing [%s:%d] : '%s %s %s' expects <header_name> as argument.\n",
-							 file, linenum, args[0], args[1], args[cur_arg]);
-						err_code |= ERR_ALERT | ERR_FATAL;
-						goto out;
-					}
-					istfree(&curproxy->orgto_hdr_name);
-					curproxy->orgto_hdr_name = istdup(ist(args[cur_arg+1]));
-					if (!isttest(curproxy->orgto_hdr_name))
-						goto alloc_error;
-					cur_arg += 2;
-				} else {
-					/* unknown suboption - catchall */
-					ha_alert("parsing [%s:%d] : '%s %s' only supports optional values: 'except' and 'header'.\n",
-						 file, linenum, args[0], args[1]);
-					err_code |= ERR_ALERT | ERR_FATAL;
-					goto out;
-				}
-			} /* end while loop */
+			err_code |= proxy_http_parse_xot(args, 0, curproxy, curr_defproxy, file, linenum);
+			if (err_code & ERR_FATAL)
+				goto out;
 		}
 		else if (strcmp(args[1], "http-restrict-req-hdr-names") == 0) {
 			if (alertif_too_many_args(2, file, linenum, args, &err_code))
diff --git a/src/cfgparse.c b/src/cfgparse.c
index 358a587..ecb75a7 100644
--- a/src/cfgparse.c
+++ b/src/cfgparse.c
@@ -3982,11 +3982,11 @@
 				curproxy->options &= ~PR_O_HTTP_XFF;
 			}
 
-			if (curproxy->options & PR_O_ORGTO) {
+			if (curproxy->options & PR_O_HTTP_XOT) {
 				ha_warning("'option %s' ignored for %s '%s' as it requires HTTP mode.\n",
 					   "originalto", proxy_type_str(curproxy), curproxy->id);
 				err_code |= ERR_WARN;
-				curproxy->options &= ~PR_O_ORGTO;
+				curproxy->options &= ~PR_O_HTTP_XOT;
 			}
 
 			for (optnum = 0; cfg_opts[optnum].name; optnum++) {
diff --git a/src/http_ana.c b/src/http_ana.c
index 3601471..fe5044e 100644
--- a/src/http_ana.c
+++ b/src/http_ana.c
@@ -678,53 +678,12 @@
 	}
 
 	/*
-	 * 10: add X-Original-To if either the frontend or the backend
+	 * add X-Original-To if either the frontend or the backend
 	 * asks for it.
 	 */
-	if ((sess->fe->options | s->be->options) & PR_O_ORGTO) {
-		const struct sockaddr_storage *dst = sc_dst(s->scf);
-		struct ist hdr = isttest(s->be->orgto_hdr_name) ? s->be->orgto_hdr_name : sess->fe->orgto_hdr_name;
-
-		if (dst && dst->ss_family == AF_INET) {
-			/* Add an X-Original-To header unless the destination IP is
-			 * in the 'except' network range.
-			 */
-			if (ipcmp2net(dst, &sess->fe->except_xot_net) &&
-			    ipcmp2net(dst, &s->be->except_xot_net)) {
-				unsigned char *pn = (unsigned char *)&((struct sockaddr_in *)dst)->sin_addr;
-
-				/* Note: we rely on the backend to get the header name to be used for
-				 * x-original-to, because the header is really meant for the backends.
-				 * However, if the backend did not specify any option, we have to rely
-				 * on the frontend's header name.
-				 */
-				chunk_printf(&trash, "%d.%d.%d.%d", pn[0], pn[1], pn[2], pn[3]);
-				if (unlikely(!http_add_header(htx, hdr, ist2(trash.area, trash.data))))
-					goto return_fail_rewrite;
-			}
-		}
-		else if (dst && dst->ss_family == AF_INET6) {
-			/* Add an X-Original-To header unless the source IP is
-			 * in the 'except' network range.
-			 */
-			if (ipcmp2net(dst, &sess->fe->except_xot_net) &&
-			    ipcmp2net(dst, &s->be->except_xot_net)) {
-				char pn[INET6_ADDRSTRLEN];
-
-				inet_ntop(AF_INET6,
-					  (const void *)&((struct sockaddr_in6 *)dst)->sin6_addr,
-					  pn, sizeof(pn));
-
-				/* Note: we rely on the backend to get the header name to be used for
-				 * x-forwarded-for, because the header is really meant for the backends.
-				 * However, if the backend did not specify any option, we have to rely
-				 * on the frontend's header name.
-				 */
-				chunk_printf(&trash, "%s", pn);
-				if (unlikely(!http_add_header(htx, hdr, ist2(trash.area, trash.data))))
-					goto return_fail_rewrite;
-			}
-		}
+	if ((sess->fe->options | s->be->options) & PR_O_HTTP_XOT) {
+		if (unlikely(!http_handle_xot_header(s, req)))
+			goto return_fail_rewrite;
 	}
 
 	/* Filter the request headers if there are filters attached to the
diff --git a/src/http_ext.c b/src/http_ext.c
index e5c39c2..6a922e6 100644
--- a/src/http_ext.c
+++ b/src/http_ext.c
@@ -828,6 +828,67 @@
 	return 1;
 }
 
+/* This function will try to inject x-original-to header if
+ * configured on the frontend or the backend (or both)
+ * Returns 1 for success and 0 for failure
+ */
+int http_handle_xot_header(struct stream *s, struct channel *req)
+{
+	struct session *sess = s->sess;
+	struct htx *htx = htxbuf(&req->buf);
+	const struct sockaddr_storage *dst = sc_dst(s->scf);
+	struct http_ext_xot *f_xot = ((sess->fe->options & PR_O_HTTP_XOT) ? &sess->fe->http.xot : NULL);
+	struct http_ext_xot *b_xot = ((s->be->options & PR_O_HTTP_XOT) ? &s->be->http.xot : NULL);
+	struct ist hdr;
+
+	/* xot is expected to be enabled on be, or fe, or both */
+	BUG_ON(!f_xot && !b_xot);
+
+	hdr = ((b_xot) ? b_xot->hdr_name : f_xot->hdr_name);
+
+	if (dst && dst->ss_family == AF_INET) {
+		/* Add an X-Original-To header unless the destination IP is
+		 * in the 'except' network range.
+		 */
+		if ((!f_xot || ipcmp2net(dst, &f_xot->except_net)) &&
+		    (!b_xot || ipcmp2net(dst, &b_xot->except_net))) {
+			unsigned char *pn = (unsigned char *)&((struct sockaddr_in *)dst)->sin_addr;
+
+			/* Note: we rely on the backend to get the header name to be used for
+			 * x-original-to, because the header is really meant for the backends.
+			 * However, if the backend did not specify any option, we have to rely
+			 * on the frontend's header name.
+			 */
+			chunk_printf(&trash, "%d.%d.%d.%d", pn[0], pn[1], pn[2], pn[3]);
+			if (unlikely(!http_add_header(htx, hdr, ist2(trash.area, trash.data))))
+				return 0;
+		}
+	}
+	else if (dst && dst->ss_family == AF_INET6) {
+		/* Add an X-Original-To header unless the source IP is
+		 * in the 'except' network range.
+		 */
+		if ((!f_xot || ipcmp2net(dst, &f_xot->except_net)) &&
+		    (!b_xot || ipcmp2net(dst, &b_xot->except_net))) {
+			char pn[INET6_ADDRSTRLEN];
+
+			inet_ntop(AF_INET6,
+				  (const void *)&((struct sockaddr_in6 *)dst)->sin6_addr,
+				  pn, sizeof(pn));
+
+			/* Note: we rely on the backend to get the header name to be used for
+			 * x-forwarded-for, because the header is really meant for the backends.
+			 * However, if the backend did not specify any option, we have to rely
+			 * on the frontend's header name.
+			 */
+			chunk_printf(&trash, "%s", pn);
+			if (unlikely(!http_add_header(htx, hdr, ist2(trash.area, trash.data))))
+				return 0;
+		}
+	}
+	return 1;
+}
+
 /*
  * =========== CONFIG ===========
  * below are helpers to parse http ext options from the config
@@ -1150,6 +1211,78 @@
 	return err_code;
 }
 
+/* x-original-to */
+int proxy_http_parse_xot(char **args, int cur_arg,
+                         struct proxy *curproxy, const struct proxy *defpx,
+                         const char *file, int linenum)
+{
+	int err_code = 0;
+
+	/* insert x-original-to field, but not for the IP address listed as an except.
+	 * set default options (ie: bitfield, header name, etc)
+	 */
+
+	curproxy->options |= PR_O_HTTP_XOT;
+
+	istfree(&curproxy->http.xot.hdr_name);
+	curproxy->http.xot.hdr_name = istdup(ist(DEF_XORIGINALTO_HDR));
+	if (!isttest(curproxy->http.xot.hdr_name))
+		return proxy_http_parse_oom(file, linenum);
+	curproxy->http.xot.except_net.family = AF_UNSPEC;
+
+	/* loop to go through arguments - start at 2, since 0+1 = "option" "originalto" */
+	cur_arg = 2;
+	while (*(args[cur_arg])) {
+		if (strcmp(args[cur_arg], "except") == 0) {
+			unsigned char mask;
+			int i;
+
+			/* suboption except - needs additional argument for it */
+			if (*(args[cur_arg+1]) &&
+			    str2net(args[cur_arg+1], 1, &curproxy->http.xot.except_net.addr.v4.ip, &curproxy->http.xot.except_net.addr.v4.mask)) {
+				curproxy->http.xot.except_net.family = AF_INET;
+				curproxy->http.xot.except_net.addr.v4.ip.s_addr &= curproxy->http.xot.except_net.addr.v4.mask.s_addr;
+			}
+			else if (*(args[cur_arg+1]) &&
+				 str62net(args[cur_arg+1], &curproxy->http.xot.except_net.addr.v6.ip, &mask)) {
+				curproxy->http.xot.except_net.family = AF_INET6;
+				len2mask6(mask, &curproxy->http.xot.except_net.addr.v6.mask);
+				for (i = 0; i < 16; i++)
+					curproxy->http.xot.except_net.addr.v6.ip.s6_addr[i] &= curproxy->http.xot.except_net.addr.v6.mask.s6_addr[i];
+			}
+			else {
+				ha_alert("parsing [%s:%d] : '%s %s %s' expects <address>[/mask] as argument.\n",
+					 file, linenum, args[0], args[1], args[cur_arg]);
+				err_code |= ERR_ALERT | ERR_FATAL;
+				goto out;
+			}
+			cur_arg += 2;
+		} else if (strcmp(args[cur_arg], "header") == 0) {
+			/* suboption header - needs additional argument for it */
+			if (*(args[cur_arg+1]) == 0) {
+				ha_alert("parsing [%s:%d] : '%s %s %s' expects <header_name> as argument.\n",
+					 file, linenum, args[0], args[1], args[cur_arg]);
+				err_code |= ERR_ALERT | ERR_FATAL;
+				goto out;
+			}
+			istfree(&curproxy->http.xot.hdr_name);
+			curproxy->http.xot.hdr_name = istdup(ist(args[cur_arg+1]));
+			if (!isttest(curproxy->http.xot.hdr_name))
+				return proxy_http_parse_oom(file, linenum);
+			cur_arg += 2;
+		} else {
+			/* unknown suboption - catchall */
+			ha_alert("parsing [%s:%d] : '%s %s' only supports optional values: 'except' and 'header'.\n",
+				 file, linenum, args[0], args[1]);
+			err_code |= ERR_ALERT | ERR_FATAL;
+			goto out;
+		}
+	} /* end while loop */
+
+ out:
+	return err_code;
+}
+
 /*
  * =========== MGMT ===========
  * below are helpers to manage http ext options
@@ -1181,6 +1314,11 @@
 	istfree(&clean->hdr_name);
 }
 
+void http_ext_xot_clean(struct http_ext_xot *clean)
+{
+	istfree(&clean->hdr_name);
+}
+
 void http_ext_7239_copy(struct http_ext_7239 *dest, const struct http_ext_7239 *orig)
 {
 	if (orig->c_file)
@@ -1217,3 +1355,10 @@
 	dest->mode = orig->mode;
 	dest->except_net = orig->except_net;
 }
+
+void http_ext_xot_copy(struct http_ext_xot *dest, const struct http_ext_xot *orig)
+{
+	if (isttest(orig->hdr_name))
+		dest->hdr_name = istdup(orig->hdr_name);
+	dest->except_net = orig->except_net;
+}
diff --git a/src/proxy.c b/src/proxy.c
index 802d3c7..efb8ddb 100644
--- a/src/proxy.c
+++ b/src/proxy.c
@@ -352,9 +352,9 @@
 		pxdf->fct(p);
 
 	free(p->desc);
-	istfree(&p->orgto_hdr_name);
 	http_ext_7239_clean(&p->http.fwd);
 	http_ext_xff_clean(&p->http.xff);
+	http_ext_xot_clean(&p->http.xot);
 
 	task_destroy(p->task);
 
@@ -1465,11 +1465,11 @@
 	istfree(&defproxy->monitor_uri);
 	ha_free(&defproxy->defbe.name);
 	ha_free(&defproxy->conn_src.iface_name);
-	istfree(&defproxy->orgto_hdr_name);
 	istfree(&defproxy->server_id_hdr_name);
 
 	http_ext_7239_clean(&defproxy->http.fwd);
 	http_ext_xff_clean(&defproxy->http.xff);
+	http_ext_xot_clean(&defproxy->http.xot);
 
 	list_for_each_entry_safe(acl, aclb, &defproxy->acl, list) {
 		LIST_DELETE(&acl->list);
@@ -1646,16 +1646,14 @@
 	curproxy->options2 = defproxy->options2;
 	curproxy->no_options = defproxy->no_options;
 	curproxy->no_options2 = defproxy->no_options2;
-	curproxy->except_xot_net = defproxy->except_xot_net;
 	curproxy->retry_type = defproxy->retry_type;
 	curproxy->tcp_req.inspect_delay = defproxy->tcp_req.inspect_delay;
 	curproxy->tcp_rep.inspect_delay = defproxy->tcp_rep.inspect_delay;
 
 	if (defproxy->options & PR_O_HTTP_XFF)
 		http_ext_xff_copy(&curproxy->http.xff, &defproxy->http.xff);
-
-	if (isttest(defproxy->orgto_hdr_name))
-		curproxy->orgto_hdr_name = istdup(defproxy->orgto_hdr_name);
+	if (defproxy->options & PR_O_HTTP_XOT)
+		http_ext_xot_copy(&curproxy->http.xot, &defproxy->http.xot);
 
 	if (isttest(defproxy->server_id_hdr_name))
 		curproxy->server_id_hdr_name = istdup(defproxy->server_id_hdr_name);