redact_pii: memcpy-based impl with format mode split in cfg.y

Author: kordian-pawelec

cfg.y

@@ -1598,6 +1598,20 @@ assign_stm: LOGLEVEL EQUAL snumber { IFOR();
 		| REDACT_PII_ error { yyerror("boolean value expected"); }
 		| REDACT_TEMPLATE EQUAL STRING { IFOR();
 										redact_template=$3;
+										if (redact_mode == REDACT_FORMAT) {
+											char *pct = strstr(redact_template, "%s");
+											if (pct) {
+												redact_fmt.left.s = redact_template;
+												redact_fmt.left.len = pct - redact_template;
+												redact_fmt.right.s = pct + 2;
+												redact_fmt.right.len = strlen(pct + 2);
+											} else {
+												redact_fmt.left.s = redact_template;
+												redact_fmt.left.len = strlen(redact_template);
+												redact_fmt.right.s = "";
+												redact_fmt.right.len = 0;
+											}
+										}
 									}
 		| REDACT_TEMPLATE error { yyerror("string value expected"); }
 		| REDACT_MODE EQUAL STRING { IFOR();
@@ -1607,8 +1621,23 @@ assign_stm: LOGLEVEL EQUAL snumber { IFOR();
 											redact_mode=REDACT_APPEND;
 										else if (strcasecmp($3, "prepend")==0)
 											redact_mode=REDACT_PREPEND;
-										else if (strcasecmp($3, "format")==0)
+										else if (strcasecmp($3, "format")==0) {
 											redact_mode=REDACT_FORMAT;
+											if (redact_template) {
+												char *pct = strstr(redact_template, "%s");
+												if (pct) {
+													redact_fmt.left.s = redact_template;
+													redact_fmt.left.len = pct - redact_template;
+													redact_fmt.right.s = pct + 2;
+													redact_fmt.right.len = strlen(pct + 2);
+												} else {
+													redact_fmt.left.s = redact_template;
+													redact_fmt.left.len = strlen(redact_template);
+													redact_fmt.right.s = "";
+													redact_fmt.right.len = 0;
+												}
+											}
+										}
 										else
 											yyerror("redact_mode must be: replace|append|prepend|format");
 									}

redact_pii.c

@@ -1,31 +1,59 @@
 #include <string.h>
-#include <stdio.h>
 #include "ut.h"
 #include "redact_pii.h"
 
 int redact_pii_ = 0;
 char *redact_template = "****";
 int redact_mode = REDACT_REPLACE;
+redact_log_format_t redact_fmt = {{NULL, 0}, {NULL, 0}};
+
+#define REDACT_BUF_SIZE 512
 
 inline const char* redact_pii(const char* input) {
-    static char buf[512];
-    const char *safe = ZSW(input);
+	static char buf[REDACT_BUF_SIZE];
+	const char *safe = ZSW(input);
+	size_t input_len, idx;
 
-    if (!redact_pii_)
-        return safe;
+	if (!redact_pii_)
+		return safe;
 
-    switch (redact_mode) {
-    case REDACT_APPEND:
-        snprintf(buf, sizeof(buf), "%s%s", safe, redact_template);
-        return buf;
-    case REDACT_PREPEND:
-        snprintf(buf, sizeof(buf), "%s%s", redact_template, safe);
-        return buf;
-    case REDACT_FORMAT:
-        snprintf(buf, sizeof(buf), redact_template, safe);
-        return buf;
-    case REDACT_REPLACE:
-    default:
-        return redact_template;
-    }
+	switch (redact_mode) {
+	case REDACT_REPLACE:
+		return redact_template;
+	case REDACT_APPEND:
+		input_len = strlen(safe);
+		idx = 0;
+		memcpy(buf + idx, safe, input_len);
+		idx += input_len;
+		memcpy(buf + idx, redact_template, strlen(redact_template));
+		idx += strlen(redact_template);
+		buf[idx] = '\0';
+		return buf;
+	case REDACT_PREPEND:
+		input_len = strlen(safe);
+		idx = 0;
+		memcpy(buf + idx, redact_template, strlen(redact_template));
+		idx += strlen(redact_template);
+		memcpy(buf + idx, safe, input_len);
+		idx += input_len;
+		buf[idx] = '\0';
+		return buf;
+	case REDACT_FORMAT:
+		input_len = strlen(safe);
+		idx = 0;
+		if (redact_fmt.left.len > 0) {
+			memcpy(buf + idx, redact_fmt.left.s, redact_fmt.left.len);
+			idx += redact_fmt.left.len;
+		}
+		memcpy(buf + idx, safe, input_len);
+		idx += input_len;
+		if (redact_fmt.right.len > 0) {
+			memcpy(buf + idx, redact_fmt.right.s, redact_fmt.right.len);
+			idx += redact_fmt.right.len;
+		}
+		buf[idx] = '\0';
+		return buf;
+	default:
+		return redact_template;
+	}
 }

redact_pii.h

@@ -20,16 +20,24 @@
 #ifndef redact_pii_h
 #define redact_pii_h
 
+#include "str.h"
+
 enum {
     REDACT_REPLACE = 0,
     REDACT_APPEND,
     REDACT_PREPEND,
     REDACT_FORMAT
 };
 
+typedef struct {
+    str left;
+    str right;
+} redact_log_format_t;
+
 extern int redact_pii_;
 extern char *redact_template;
 extern int redact_mode;
+extern redact_log_format_t redact_fmt;
 
 const char* redact_pii(const char* input);