From 151f1205ec5aeaed68c69c7693b34dbe703e40dc Mon Sep 17 00:00:00 2001
From: Michael Ortmann <41313082+michaelortmann@users.noreply.github.com>
Date: Mon, 19 Oct 2020 15:21:58 +0200
Subject: [PATCH 1/2] Refactor dccutil.c:add_cr() and dcc.c:escape_telnet()
 into a single misc.c:add_cr()

---
 src/dcc.c     | 20 ++------------------
 src/dccutil.c | 17 +----------------
 src/misc.c    | 23 +++++++++++++++++++++++
 src/proto.h   |  2 +-
 4 files changed, 27 insertions(+), 35 deletions(-)

diff --git a/src/dcc.c b/src/dcc.c
index b72221038..d337dd475 100644
--- a/src/dcc.c
+++ b/src/dcc.c
@@ -90,22 +90,6 @@ static int detect_telnet(unsigned char *buf)
   return 0;
 }
 
-/* Escape telnet IAC and prepend CR to LF */
-static char *escape_telnet(char *s)
-{
-  static char buf[1024];
-  char *p;
-
-  for (p = buf; *s && (p < (buf + sizeof(buf) - 2)); *p++ = *s++)
-    if ((unsigned char) *s == TLN_IAC)
-      *p++ = *s;
-    else if (*s == '\n')
-      *p++ = '\r';
-  *p = 0;
-
-  return buf;
-}
-
 static void strip_telnet(int sock, char *buf, int *len)
 {
   unsigned char *p = (unsigned char *) buf, *o = (unsigned char *) buf;
@@ -929,7 +913,7 @@ static void out_dcc_general(int idx, char *buf, void *x)
 
   strip_mirc_codes(p->strip_flags, buf);
   if (dcc[idx].status & STAT_TELNET)
-    y = escape_telnet(buf);
+    y = add_cr(buf, 1);
   if (dcc[idx].status & STAT_PAGE)
     append_line(idx, y);
   else
@@ -1768,7 +1752,7 @@ static void dcc_telnet_pass(int idx, int atr)
     /* Turn off remote telnet echo (send IAC WILL ECHO). */
     if (dcc[idx].status & STAT_TELNET) {
       char buf[1030];
-      egg_snprintf(buf, sizeof buf, "\n%s%s\r\n", escape_telnet(DCC_ENTERPASS),
+      egg_snprintf(buf, sizeof buf, "\n%s%s\r\n", add_cr(DCC_ENTERPASS, 1),
                TLN_IAC_C TLN_WILL_C TLN_ECHO_C);
       tputs(dcc[idx].sock, buf, strlen(buf));
     } else
diff --git a/src/dccutil.c b/src/dccutil.c
index c9fca244e..a05b1dd56 100644
--- a/src/dccutil.c
+++ b/src/dccutil.c
@@ -132,21 +132,6 @@ int findanyidx(int z)
   return -1;
 }
 
-/* Replace \n with \r\n */
-char *add_cr(char *buf)
-{
-  static char WBUF[1024];
-  char *p, *q;
-
-  for (p = buf, q = WBUF; *p; p++, q++) {
-    if (*p == '\n')
-      *q++ = '\r';
-    *q = *p;
-  }
-  *q = *p;
-  return WBUF;
-}
-
 extern void (*qserver) (int, char *, int);
 
 void dprintf EGG_VARARGS_DEF(int, arg1)
@@ -208,7 +193,7 @@ void dprint(int idx, char *buf, int len)
       len = LOGLINEMAX-10;
     }
     if (dcc[idx].type && ((long) (dcc[idx].type->output) == 1)) {
-      char *p = add_cr(buf);
+      char *p = add_cr(buf, 0);
 
       tputs(dcc[idx].sock, p, strlen(p));
     } else if (dcc[idx].type && dcc[idx].type->output)
diff --git a/src/misc.c b/src/misc.c
index 256f654e2..a22ab8641 100644
--- a/src/misc.c
+++ b/src/misc.c
@@ -1575,3 +1575,26 @@ void kill_bot(char *s1, char *s2)
   write_userfile(-1);
   fatal(s2, 2);
 }
+
+/* Prepend CR to LF (Replace \n with \r\n) and escape telnet IAC if
+ * escape_telnet is set
+ */
+char *add_cr(const char *p, const int escape_telnet)
+{
+  static int buf_size = 0;
+  static char *buf;
+  char *q;
+
+  if ((strlen(p) << 1) > buf_size) {
+    buf_size = strlen(p) << 1;
+    buf = nrealloc(buf, buf_size);
+  }
+  for (q = buf; *p; *q++ = *p++) {
+    if (escape_telnet && ((unsigned char) *p == TLN_IAC))
+      *q++ = *p;
+    else if (*p == '\n')
+      *q++ = '\r';
+  }
+  *q = 0;
+  return buf;
+}
diff --git a/src/proto.h b/src/proto.h
index cc394e709..18d9c1b4e 100644
--- a/src/proto.h
+++ b/src/proto.h
@@ -137,7 +137,6 @@ int dcc_fingerprint(int);
 int increase_socks_max();
 int findidx(int);
 int findanyidx(int);
-char *add_cr(char *);
 void dprint(int, char *, int);
 void dprintf EGG_VARARGS(int, arg1);
 void chatout EGG_VARARGS(char *, arg1);
@@ -261,6 +260,7 @@ char *strchr_unescape(char *, const char, const char);
 void str_unescape(char *, const char);
 int str_isdigit(const char *);
 void kill_bot(char *, char *);
+char *add_cr(const char *, const int);
 
 void maskaddr(const char *, char *, int);
 #define maskhost(a,b) maskaddr((a),(b),3)

From 51fea86d92806696e6dc47ed2d5afa69274889e6 Mon Sep 17 00:00:00 2001
From: Michael Ortmann <41313082+michaelortmann@users.noreply.github.com>
Date: Wed, 10 Jul 2024 19:20:36 +0200
Subject: [PATCH 2/2] Fix off-by-one error

---
 src/misc.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/src/misc.c b/src/misc.c
index 5e5e7d3e0..f51d1af75 100644
--- a/src/misc.c
+++ b/src/misc.c
@@ -1596,12 +1596,14 @@ int crypto_verify(const char *x_, const char *y_)
  */
 char *add_cr(const char *p, const int escape_telnet)
 {
-  static int buf_size = 0;
+  size_t len;
+  static size_t buf_size = 0;
   static char *buf;
   char *q;
 
-  if ((strlen(p) << 1) > buf_size) {
-    buf_size = strlen(p) << 1;
+  len = (strlen(p) << 1) + 1;
+  if (len > buf_size) {
+    buf_size = len;
     buf = nrealloc(buf, buf_size);
   }
   for (q = buf; *p; *q++ = *p++) {