From 80ed6dea3ebffe22ff43602ae85662cecacf4a45 Mon Sep 17 00:00:00 2001
From: Lorenz Stechauner <lorenz.stechauner@necronda.net>
Date: Wed, 16 Dec 2020 18:35:11 +0100
Subject: [PATCH] Added http header strict and not strict mode

---
 src/client.c |  4 ++--
 src/http.c   | 12 ++++++------
 src/http.h   |  7 +++++--
 3 files changed, 13 insertions(+), 10 deletions(-)

diff --git a/src/client.c b/src/client.c
index 0ea80f5..50368ce 100644
--- a/src/client.c
+++ b/src/client.c
@@ -79,9 +79,9 @@ int client_request_handler(sock *client, int req_num) {
         goto respond;
     }
 
-    hdr_connection = http_get_header_field(&req.hdr, "Connection");
+    hdr_connection = http_get_header_field(&req.hdr, "Connection", HTTP_NOT_STRICT);
     client_keep_alive = hdr_connection != NULL && strncmp(hdr_connection, "keep-alive", 10) == 0;
-    host = http_get_header_field(&req.hdr, "Host");
+    host = http_get_header_field(&req.hdr, "Host", HTTP_NOT_STRICT);
     if (host == NULL || strchr(host, '/') != NULL) {
         res.status = http_get_status(400);
         sprintf(err_msg, "The client provided no or an invalid Host header field.");
diff --git a/src/http.c b/src/http.c
index 2bdce14..35a3aa7 100644
--- a/src/http.c
+++ b/src/http.c
@@ -9,14 +9,14 @@
 #include "utils.h"
 
 
-void http_to_camel_case(char *str) {
+void http_to_camel_case(char *str, int strict) {
     char last = '-';
     char ch;
     for (int i = 0; i < strlen(str); i++) {
         ch = str[i];
         if (last == '-' && ch >= 'a' && ch <= 'z') {
             str[i] = (char) ((int) ch & 0x5F);
-        } else if (last != '-' && ch >= 'A' && ch <= 'Z') {
+        } else if (last != '-' && ch >= 'A' && ch <= 'Z' && strict == HTTP_STRICT) {
             str[i] = (char) ((int) ch | 0x20);
         }
         last = str[i];
@@ -132,7 +132,7 @@ int http_receive_request(sock *client, http_req *req) {
                 len = pos1 - ptr;
                 req->hdr.fields[req->hdr.field_num][0] = malloc(len + 1);
                 sprintf(req->hdr.fields[req->hdr.field_num][0], "%.*s", (int) len, ptr);
-                http_to_camel_case(req->hdr.fields[req->hdr.field_num][0]);
+                http_to_camel_case(req->hdr.fields[req->hdr.field_num][0], HTTP_NOT_STRICT);
 
                 pos1++;
                 pos2 = pos0 - 1;
@@ -153,11 +153,11 @@ int http_receive_request(sock *client, http_req *req) {
     }
 }
 
-char *http_get_header_field(http_hdr *hdr, const char *field_name) {
+char *http_get_header_field(http_hdr *hdr, const char *field_name, int strict) {
     size_t len = strlen(field_name);
     char *_field_name = malloc(len + 1);
     strcpy(_field_name, field_name);
-    http_to_camel_case(_field_name);
+    http_to_camel_case(_field_name, strict);
     for (int i = 0; i < hdr->field_num; i++) {
         if (strncmp(hdr->fields[i][0], _field_name, len) == 0) {
             free(_field_name);
@@ -175,7 +175,7 @@ void http_add_header_field(http_hdr *hdr, const char *field_name, const char *fi
     char *_field_value = malloc(len_value + 1);
     strcpy(_field_name, field_name);
     strcpy(_field_value, field_value);
-    http_to_camel_case(_field_name);
+    http_to_camel_case(_field_name, HTTP_NOT_STRICT);
     hdr->fields[hdr->field_num][0] = _field_name;
     hdr->fields[hdr->field_num][1] = _field_value;
     hdr->field_num++;
diff --git a/src/http.h b/src/http.h
index bcbb9a5..da19bad 100644
--- a/src/http.h
+++ b/src/http.h
@@ -8,6 +8,9 @@
 #ifndef NECRONDA_SERVER_HTTP_H
 #define NECRONDA_SERVER_HTTP_H
 
+#define HTTP_STRICT 1
+#define HTTP_NOT_STRICT 0
+
 typedef struct {
     unsigned short code;
     char type[16];
@@ -151,7 +154,7 @@ const char *http_error_icon =
         "eTonQXJpYWwnLHNhbnMtc2VyaWYiPjooPC90ZXh0Pjwvc3ZnPgo=\"/>\n";
 
 
-void http_to_camel_case(char *str);
+void http_to_camel_case(char *str, int strict);
 
 void http_free_hdr(http_hdr *hdr);
 
@@ -161,7 +164,7 @@ void http_free_res(http_res *res);
 
 int http_receive_request(sock *client, http_req *req);
 
-char *http_get_header_field(http_hdr *hdr, const char *field_name);
+char *http_get_header_field(http_hdr *hdr, const char *field_name, int strict);
 
 void http_add_header_field(http_hdr *hdr, const char *field_name, const char *field_value);