From c38224099e0ddaaddd34c9feeb4fd25002183112 Mon Sep 17 00:00:00 2001
From: JacobBarthelmeh <jacob@wolfssl.com>
Date: Tue, 7 Nov 2023 02:31:10 -0800
Subject: [PATCH] increase type size for command name and improve handling read
 of pipes after command exits

---
 apps/wolfsshd/wolfsshd.c | 24 ++++++++++++++++++++----
 wolfssh/internal.h       |  2 +-
 2 files changed, 21 insertions(+), 5 deletions(-)

diff --git a/apps/wolfsshd/wolfsshd.c b/apps/wolfsshd/wolfsshd.c
index 738fde9ea..7cd4c49df 100644
--- a/apps/wolfsshd/wolfsshd.c
+++ b/apps/wolfsshd/wolfsshd.c
@@ -1166,11 +1166,15 @@ static int SHELL_Subsystem(WOLFSSHD_CONNECTION* conn, WOLFSSH* ssh,
 
 #ifndef EXAMPLE_BUFFER_SZ
     #define EXAMPLE_BUFFER_SZ 4096
+#endif
+#ifndef MAX_IDLE_COUNT
+    #define MAX_IDLE_COUNT 2
 #endif
     byte shellBuffer[EXAMPLE_BUFFER_SZ];
     byte channelBuffer[EXAMPLE_BUFFER_SZ];
     char* forcedCmd;
     int   windowFull = 0;
+    int   idle = 0;
 
     forcedCmd = wolfSSHD_ConfigGetForcedCmd(usrConf);
 
@@ -1381,7 +1385,7 @@ static int SHELL_Subsystem(WOLFSSHD_CONNECTION* conn, WOLFSSH* ssh,
         close(stderrPipe[1]);
     }
 
-    while (ChildRunning) {
+    while (idle < MAX_IDLE_COUNT) {
         byte tmp[2];
         fd_set readFds;
         WS_SOCKET_T maxFd;
@@ -1389,6 +1393,8 @@ static int SHELL_Subsystem(WOLFSSHD_CONNECTION* conn, WOLFSSH* ssh,
         int cnt_w;
         int pending = 0;
 
+        idle++; /* increment idle count, gets reset if not idle */
+
         FD_ZERO(&readFds);
         FD_SET(sshFd, &readFds);
         maxFd = sshFd;
@@ -1416,6 +1422,7 @@ static int SHELL_Subsystem(WOLFSSHD_CONNECTION* conn, WOLFSSH* ssh,
         }
         else {
             pending = 1; /* found some pending SSH data */
+            idle    = 0;
         }
 
         if (windowFull || pending || FD_ISSET(sshFd, &readFds)) {
@@ -1431,6 +1438,7 @@ static int SHELL_Subsystem(WOLFSSHD_CONNECTION* conn, WOLFSSH* ssh,
             if (cnt_r < 0) {
                 rc = wolfSSH_get_error(ssh);
                 if (rc == WS_CHAN_RXD) {
+                    idle = 0;
                     if (lastChannel == shellChannelId) {
                         cnt_r = wolfSSH_ChannelIdRead(ssh, shellChannelId,
                                 channelBuffer,
@@ -1458,6 +1466,7 @@ static int SHELL_Subsystem(WOLFSSHD_CONNECTION* conn, WOLFSSH* ssh,
                     shellBuffer, cnt_r);
             if (cnt_w == WS_WINDOW_FULL) {
                 windowFull = 1;
+                idle = 0;
                 continue;
             }
             else {
@@ -1472,12 +1481,13 @@ static int SHELL_Subsystem(WOLFSSHD_CONNECTION* conn, WOLFSSH* ssh,
                 /* This read will return 0 on EOF */
                 if (cnt_r <= 0) {
                     int err = errno;
-                    if (err != EAGAIN) {
+                    if (err != EAGAIN && err != 0) {
                         break;
                     }
                 }
                 else {
                     if (cnt_r > 0) {
+                        idle = 0;
                         cnt_w = wolfSSH_extended_data_send(ssh, shellBuffer,
                             cnt_r);
                         if (cnt_w == WS_WINDOW_FULL) {
@@ -1497,12 +1507,13 @@ static int SHELL_Subsystem(WOLFSSHD_CONNECTION* conn, WOLFSSH* ssh,
                 /* This read will return 0 on EOF */
                 if (cnt_r <= 0) {
                     int err = errno;
-                    if (err != EAGAIN) {
+                    if (err != EAGAIN && err != 0) {
                         break;
                     }
                 }
                 else {
                     if (cnt_r > 0) {
+                        idle = 0;
                         cnt_w = wolfSSH_ChannelIdSend(ssh, shellChannelId,
                                 shellBuffer, cnt_r);
                         if (cnt_w == WS_WINDOW_FULL) {
@@ -1521,12 +1532,13 @@ static int SHELL_Subsystem(WOLFSSHD_CONNECTION* conn, WOLFSSH* ssh,
                 /* This read will return 0 on EOF */
                 if (cnt_r <= 0) {
                     int err = errno;
-                    if (err != EAGAIN) {
+                    if (err != EAGAIN && err != 0) {
                         break;
                     }
                 }
                 else {
                     if (cnt_r > 0) {
+                        idle = 0;
                         cnt_w = wolfSSH_ChannelIdSend(ssh, shellChannelId,
                                 shellBuffer, cnt_r);
                         if (cnt_w == WS_WINDOW_FULL) {
@@ -1539,6 +1551,10 @@ static int SHELL_Subsystem(WOLFSSHD_CONNECTION* conn, WOLFSSH* ssh,
                 }
             }
         }
+
+        if (ChildRunning && idle) {
+            idle = 0; /* waiting on child process */
+        }
     }
 
     /* check for any left over data in pipes then close them */
diff --git a/wolfssh/internal.h b/wolfssh/internal.h
index e06b515d1..827763e5d 100644
--- a/wolfssh/internal.h
+++ b/wolfssh/internal.h
@@ -715,7 +715,7 @@ struct WOLFSSH {
     word32 defaultPeerChannelId;
     word32 connectChannelId;
     byte channelName[WOLFSSH_MAX_CHN_NAMESZ];
-    byte channelNameSz;
+    word32 channelNameSz;
     word32 lastRxId;
 
     WOLFSSH_BUFFER inputBuffer;