Added string copy function that only copies specified amount of characters

3 files changed, 31 insertions, 5 deletions

diff --git a/cwebhook.c b/cwebhook.c
index 5dd6126..1e22d23 100644
--- a/cwebhook.c
+++ b/cwebhook.c
@@ -18,6 +18,7 @@
 #include <openssl/ssl.h>
 #include <cjson/cJSON.h>
 #include "structs.h"
+#include "str_fns.h"
 #include "https_server_structs.h"
 #include "log.h"
 #include "load_config.h"
diff --git a/http_headers.h b/http_headers.h
index 3503bf1..71d376a 100644
--- a/http_headers.h
+++ b/http_headers.h
@@ -8,7 +8,8 @@ int get_request_data( http_request_data_t *hdt, char *req_contents ){
     hdt->request_copy = (char*)calloc( hdt->request_size, sizeof(char) );
     if ( hdt->request_copy == NULL )
         return REQ_READ_ERROR;
-    strncpy( hdt->request_copy, req_contents, hdt->request_size );
+    if ( !str_copy(hdt->request_copy, req_contents, hdt->request_size) )
+        return REQ_READ_ERROR;
     if ( (size_t)strnlen(hdt->request_copy, (size_t)MAX_RECV_BYTES) != hdt->request_size )
         return REQ_READ_ERROR;
     hdt->tok_current = strtok_r( hdt->request_copy, "\r\n", &hdt->tok_prev );
@@ -22,7 +23,8 @@ int get_request_data( http_request_data_t *hdt, char *req_contents ){
     hdt->request_method = (char*)calloc( (size_t)strnlen(hdt->tok_current, (size_t)MAX_HEADER_LENGTH), sizeof(char) );
     if ( hdt->request_method == NULL )
         return REQ_READ_ERROR;
-    strncpy( hdt->request_method, hdt->tok_current, (size_t)strnlen(hdt->tok_current, (size_t)MAX_HEADER_LENGTH) );
+    if ( !str_copy(hdt->request_method, hdt->tok_current, (size_t)strnlen(hdt->tok_current, (size_t)MAX_HEADER_LENGTH)) )
+        return REQ_READ_ERROR;
     if ( (size_t)strnlen(hdt->request_method, MAX_HEADER_LENGTH) != (size_t)strnlen(hdt->tok_current, (size_t)(MAX_HEADER_LENGTH + 1)) )
         return REQ_READ_ERROR;
     hdt->tok_current = strtok_r( NULL, " ", &hdt->tok_prev );
@@ -31,11 +33,13 @@ int get_request_data( http_request_data_t *hdt, char *req_contents ){
     hdt->request_path = (char*)calloc( (size_t)strnlen(hdt->tok_current, (size_t)MAX_HEADER_LENGTH), sizeof(char) );
     if ( hdt->request_path == NULL )
         return REQ_READ_ERROR;
-    strncpy( hdt->request_path, hdt->tok_current, (size_t)strnlen(hdt->tok_current, (size_t)MAX_HEADER_LENGTH) );
+    if ( !str_copy(hdt->request_path, hdt->tok_current, (size_t)strnlen(hdt->tok_current, (size_t)MAX_HEADER_LENGTH)) )
+        return REQ_READ_ERROR;
     if ( (size_t)strnlen(hdt->request_path, (size_t)MAX_HEADER_LENGTH) != (size_t)strnlen(hdt->tok_current, (size_t)(MAX_HEADER_LENGTH + 1)) )
         return REQ_READ_ERROR;
     memset( hdt->request_copy, 0, hdt->request_size );
-    strncpy( hdt->request_copy, req_contents, hdt->request_size );
+    if ( !str_copy(hdt->request_copy, req_contents, hdt->request_size) )
+        return REQ_READ_ERROR;
     if ( (size_t)strnlen(hdt->request_copy, (size_t)(MAX_RECV_BYTES + 1)) != hdt->request_size )
         return REQ_READ_ERROR;
     char *request_body_begin = strstr( hdt->request_copy, "\r\n\r\n" );
@@ -51,7 +55,8 @@ int get_request_data( http_request_data_t *hdt, char *req_contents ){
     hdt->request_body = (char*)calloc( (size_t)strnlen(hdt->tok_current, (size_t)MAX_CONTENT_LENGTH), sizeof(char) );
     if ( hdt->request_body == NULL )
         return REQ_READ_ERROR;
-    strncpy( hdt->request_body, hdt->tok_current, (size_t)strnlen(hdt->tok_current, (size_t)MAX_CONTENT_LENGTH) );
+    if ( !str_copy(hdt->request_body, hdt->tok_current, (size_t)strnlen(hdt->tok_current, (size_t)MAX_CONTENT_LENGTH)) )
+        return REQ_READ_ERROR;
     if ( (size_t)strnlen(hdt->request_body, (size_t)MAX_CONTENT_LENGTH) != (size_t)strnlen(hdt->tok_current, (size_t)(MAX_CONTENT_LENGTH + 1)) )
         return REQ_READ_ERROR;
     return REQ_READ_SUCCESS;
diff --git a/str_fns.h b/str_fns.h
new file mode 100644
index 0000000..d580231
--- /dev/null
+++ b/str_fns.h
@@ -0,0 +1,20 @@
+bool str_copy( char *dststr, char *srcstr, size_t max_chars ){
+    if ( max_chars <= 0 )
+        return false;
+    if ( srcstr == NULL )
+        return false;
+    size_t src_len = (size_t)strnlen( srcstr, max_chars );
+    if ( src_len <= 0 )
+        return false;
+    bool need_null = false;
+    if ( src_len >= max_chars )
+        need_null = true;
+    size_t copied_chars = 0;
+    for ( ; srcstr[copied_chars] != '\0' && copied_chars < max_chars; copied_chars++ )
+        dststr[copied_chars] = srcstr[copied_chars];
+    if ( need_null )
+        dststr[copied_chars + 1] = '\0';
+    if ( strncmp((const char*)dststr, (const char*)srcstr, max_chars) != 0 )
+        return false;
+    return true;
+}