From 0b3f885d06d9fb3b267d64d5bd49792a8f88e38e Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Tue, 7 Apr 2026 14:19:08 +0000
Subject: [PATCH 01/17] fix: fetch SSH host key during setup to resolve
 StrictHostKeyChecking failure

Agent-Logs-Url: https://github.com/pacnpal/callis/sessions/4abefe1f-c4e4-4e74-ba3f-608f2861f0e5

Co-authored-by: pacnpal <183241239+pacnpal@users.noreply.github.com>
---
 api/static/callis.sh | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/api/static/callis.sh b/api/static/callis.sh
index bd60dd7..baabcda 100755
--- a/api/static/callis.sh
+++ b/api/static/callis.sh
@@ -79,6 +79,19 @@ _callis_setup() {
     chmod 600 "$CALLIS_CONFIG_FILE"
 
     echo "Configuration saved to ${CALLIS_CONFIG_FILE}"
+
+    # Fetch the SSH host key (TOFU — trust on first use) and store it in a
+    # Callis-specific known_hosts file so strict host key checking works.
+    printf "Fetching SSH host key from %s:%s...\n" "$CALLIS_HOST" "$CALLIS_PORT"
+    FETCHED=$(ssh-keyscan -p "$CALLIS_PORT" -t ed25519 "$CALLIS_HOST" 2>/dev/null)
+    if [ -n "$FETCHED" ]; then
+        printf '%s\n' "$FETCHED" > "${CALLIS_CONFIG_DIR}/known_hosts"
+        chmod 600 "${CALLIS_CONFIG_DIR}/known_hosts"
+        echo "Host key saved."
+    else
+        echo "Warning: could not fetch SSH host key from ${CALLIS_HOST}:${CALLIS_PORT}." >&2
+        echo "Run 'callis setup' again once the server is reachable." >&2
+    fi
 }
 
 _callis_load_config() {
@@ -114,8 +127,13 @@ _callis_load_config() {
 
 _callis_list() {
     _callis_load_config || return 1
+    if [ ! -f "${CALLIS_CONFIG_DIR}/known_hosts" ]; then
+        echo "Error: SSH host key not found. Run 'callis setup' to fetch it." >&2
+        return 1
+    fi
     ssh -i "$CALLIS_KEY" -p "$CALLIS_PORT" \
         -o BatchMode=yes -o StrictHostKeyChecking=yes \
+        -o UserKnownHostsFile="${CALLIS_CONFIG_DIR}/known_hosts" \
         "${CALLIS_USER}@${CALLIS_HOST}" list
 }
 
@@ -130,6 +148,11 @@ _callis_connect() {
             return 1 ;;
     esac
 
+    if [ ! -f "${CALLIS_CONFIG_DIR}/known_hosts" ]; then
+        echo "Error: SSH host key not found. Run 'callis setup' to fetch it." >&2
+        return 1
+    fi
+
     STDERR_TMP_CREATED=0
     if STDERR_TMP=$(mktemp "${TMPDIR:-/tmp}/callis-err.XXXXXX"); then
         STDERR_TMP_CREATED=1
@@ -139,6 +162,7 @@ _callis_connect() {
 
     DEST=$(ssh -i "$CALLIS_KEY" -p "$CALLIS_PORT" \
         -o BatchMode=yes -o StrictHostKeyChecking=yes \
+        -o UserKnownHostsFile="${CALLIS_CONFIG_DIR}/known_hosts" \
         "${CALLIS_USER}@${CALLIS_HOST}" "resolve ${TAG}" 2>"$STDERR_TMP")
 
     if [ -z "$DEST" ]; then
@@ -161,6 +185,7 @@ _callis_connect() {
 
     ssh -i "$CALLIS_KEY" \
         -o BatchMode=yes -o StrictHostKeyChecking=yes \
+        -o UserKnownHostsFile="${CALLIS_CONFIG_DIR}/known_hosts" \
         -J "${CALLIS_USER}@${CALLIS_HOST}:${CALLIS_PORT}" \
         -p "$TARGET_PORT" "$@" \
         "${CALLIS_USER}@${TARGET_HOST}"

From 4a0d3a7a3ca59c49f4f3003c01e2bac6ae5293d1 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Tue, 7 Apr 2026 18:55:45 +0000
Subject: [PATCH 02/17] fix: include user's known_hosts in final-hop
 UserKnownHostsFile for callis connect

Agent-Logs-Url: https://github.com/pacnpal/callis/sessions/7ae4ae7e-9fcf-4864-83f8-9a0753df3ae9

Co-authored-by: pacnpal <183241239+pacnpal@users.noreply.github.com>
---
 api/static/callis.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/api/static/callis.sh b/api/static/callis.sh
index baabcda..4ce20c0 100755
--- a/api/static/callis.sh
+++ b/api/static/callis.sh
@@ -185,7 +185,7 @@ _callis_connect() {
 
     ssh -i "$CALLIS_KEY" \
         -o BatchMode=yes -o StrictHostKeyChecking=yes \
-        -o UserKnownHostsFile="${CALLIS_CONFIG_DIR}/known_hosts" \
+        -o "UserKnownHostsFile=${CALLIS_CONFIG_DIR}/known_hosts ${HOME}/.ssh/known_hosts" \
         -J "${CALLIS_USER}@${CALLIS_HOST}:${CALLIS_PORT}" \
         -p "$TARGET_PORT" "$@" \
         "${CALLIS_USER}@${TARGET_HOST}"

From d24cdc6112ff17d8e9388305fc914fead24f739e Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Tue, 7 Apr 2026 19:44:35 +0000
Subject: [PATCH 03/17] fix: setup fails on missing key; robust known_hosts
 guard; ProxyCommand for isolated bastion verification

Agent-Logs-Url: https://github.com/pacnpal/callis/sessions/a8eae23b-7ac0-4f27-8a81-6c7fe0f66db6

Co-authored-by: pacnpal <183241239+pacnpal@users.noreply.github.com>
---
 api/static/callis.sh | 25 +++++++++++++++++--------
 1 file changed, 17 insertions(+), 8 deletions(-)

diff --git a/api/static/callis.sh b/api/static/callis.sh
index 4ce20c0..928469a 100755
--- a/api/static/callis.sh
+++ b/api/static/callis.sh
@@ -89,8 +89,9 @@ _callis_setup() {
         chmod 600 "${CALLIS_CONFIG_DIR}/known_hosts"
         echo "Host key saved."
     else
-        echo "Warning: could not fetch SSH host key from ${CALLIS_HOST}:${CALLIS_PORT}." >&2
-        echo "Run 'callis setup' again once the server is reachable." >&2
+        echo "Error: could not fetch SSH host key from ${CALLIS_HOST}:${CALLIS_PORT}." >&2
+        echo "Ensure the server is reachable and run 'callis setup' again." >&2
+        return 1
     fi
 }
 
@@ -125,10 +126,16 @@ _callis_load_config() {
     esac
 }
 
+_callis_has_known_hosts_entries() {
+    known_hosts_file="$1"
+    [ -s "$known_hosts_file" ] || return 1
+    grep -Eq '^[[:space:]]*[^#[:space:]]' "$known_hosts_file"
+}
+
 _callis_list() {
     _callis_load_config || return 1
-    if [ ! -f "${CALLIS_CONFIG_DIR}/known_hosts" ]; then
-        echo "Error: SSH host key not found. Run 'callis setup' to fetch it." >&2
+    if ! _callis_has_known_hosts_entries "${CALLIS_CONFIG_DIR}/known_hosts"; then
+        echo "Error: SSH host key file is missing, empty, or invalid. Run 'callis setup' to fetch it again." >&2
         return 1
     fi
     ssh -i "$CALLIS_KEY" -p "$CALLIS_PORT" \
@@ -148,8 +155,8 @@ _callis_connect() {
             return 1 ;;
     esac
 
-    if [ ! -f "${CALLIS_CONFIG_DIR}/known_hosts" ]; then
-        echo "Error: SSH host key not found. Run 'callis setup' to fetch it." >&2
+    if ! _callis_has_known_hosts_entries "${CALLIS_CONFIG_DIR}/known_hosts"; then
+        echo "Error: SSH host key file is missing, empty, or invalid. Run 'callis setup' to fetch it again." >&2
         return 1
     fi
 
@@ -183,10 +190,12 @@ _callis_connect() {
     TARGET_HOST=$(echo "$DEST" | awk '{print $1}')
     TARGET_PORT=$(echo "$DEST" | awk '{print $2}')
 
+    PROXY_COMMAND="ssh -i \"$CALLIS_KEY\" -p \"$CALLIS_PORT\" -o BatchMode=yes -o StrictHostKeyChecking=yes -o UserKnownHostsFile=\"${CALLIS_CONFIG_DIR}/known_hosts\" -W %h:%p \"${CALLIS_USER}@${CALLIS_HOST}\""
+
     ssh -i "$CALLIS_KEY" \
         -o BatchMode=yes -o StrictHostKeyChecking=yes \
-        -o "UserKnownHostsFile=${CALLIS_CONFIG_DIR}/known_hosts ${HOME}/.ssh/known_hosts" \
-        -J "${CALLIS_USER}@${CALLIS_HOST}:${CALLIS_PORT}" \
+        -o "UserKnownHostsFile=${HOME}/.ssh/known_hosts" \
+        -o "ProxyCommand=${PROXY_COMMAND}" \
         -p "$TARGET_PORT" "$@" \
         "${CALLIS_USER}@${TARGET_HOST}"
 }

From f1cdcaa9ade8506341a4654d333af906e2797272 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Tue, 7 Apr 2026 19:52:11 +0000
Subject: [PATCH 04/17] fix: rollback config on failure; ssh-keyscan timeout;
 fingerprint confirmation; GlobalKnownHostsFile isolation

Agent-Logs-Url: https://github.com/pacnpal/callis/sessions/0c091bb3-4d36-4819-af22-e5dba5daa332

Co-authored-by: pacnpal <183241239+pacnpal@users.noreply.github.com>
---
 api/static/callis.sh | 48 ++++++++++++++++++++++++++++++++++++++------
 1 file changed, 42 insertions(+), 6 deletions(-)

diff --git a/api/static/callis.sh b/api/static/callis.sh
index 928469a..15a4a77 100755
--- a/api/static/callis.sh
+++ b/api/static/callis.sh
@@ -80,15 +80,48 @@ _callis_setup() {
 
     echo "Configuration saved to ${CALLIS_CONFIG_FILE}"
 
-    # Fetch the SSH host key (TOFU — trust on first use) and store it in a
-    # Callis-specific known_hosts file so strict host key checking works.
+    # Fetch the SSH host key, show its fingerprint, and require explicit user
+    # confirmation before trusting it for future connections.
+    KNOWN_HOSTS_FILE="${CALLIS_CONFIG_DIR}/known_hosts"
+    TMP_KNOWN_HOSTS_FILE="${KNOWN_HOSTS_FILE}.tmp.$$"
     printf "Fetching SSH host key from %s:%s...\n" "$CALLIS_HOST" "$CALLIS_PORT"
-    FETCHED=$(ssh-keyscan -p "$CALLIS_PORT" -t ed25519 "$CALLIS_HOST" 2>/dev/null)
+    FETCHED=$(ssh-keyscan -T 10 -p "$CALLIS_PORT" -t ed25519 "$CALLIS_HOST" 2>/dev/null)
     if [ -n "$FETCHED" ]; then
-        printf '%s\n' "$FETCHED" > "${CALLIS_CONFIG_DIR}/known_hosts"
-        chmod 600 "${CALLIS_CONFIG_DIR}/known_hosts"
+        printf '%s\n' "$FETCHED" > "$TMP_KNOWN_HOSTS_FILE"
+        FINGERPRINT=$(ssh-keygen -lf "$TMP_KNOWN_HOSTS_FILE" 2>/dev/null)
+        if [ -z "$FINGERPRINT" ]; then
+            rm -f "$TMP_KNOWN_HOSTS_FILE" "$CALLIS_CONFIG_FILE"
+            echo "Error: could not compute SSH host key fingerprint for ${CALLIS_HOST}:${CALLIS_PORT}." >&2
+            return 1
+        fi
+
+        echo "Fetched SSH host key fingerprint:"
+        printf '  %s\n' "$FINGERPRINT"
+        echo "Verify this fingerprint with your administrator or another trusted out-of-band source before continuing."
+        printf "Trust and save this host key? Type 'yes' to continue: "
+        read -r TRUST_HOST_KEY
+        if [ "$TRUST_HOST_KEY" != "yes" ]; then
+            rm -f "$TMP_KNOWN_HOSTS_FILE" "$CALLIS_CONFIG_FILE"
+            echo "Host key was not saved. Setup aborted."
+            return 1
+        fi
+
+        if [ -s "$KNOWN_HOSTS_FILE" ]; then
+            echo "Warning: ${KNOWN_HOSTS_FILE} already exists and will be replaced."
+            printf "Type 'yes' to overwrite the existing Callis host key: "
+            read -r OVERWRITE_KNOWN_HOSTS
+            if [ "$OVERWRITE_KNOWN_HOSTS" != "yes" ]; then
+                rm -f "$TMP_KNOWN_HOSTS_FILE" "$CALLIS_CONFIG_FILE"
+                echo "Existing host key was left unchanged. Setup aborted."
+                return 1
+            fi
+        fi
+
+        mv "$TMP_KNOWN_HOSTS_FILE" "$KNOWN_HOSTS_FILE"
+        chmod 600 "$KNOWN_HOSTS_FILE"
         echo "Host key saved."
     else
+        rm -f "$CALLIS_CONFIG_FILE"
         echo "Error: could not fetch SSH host key from ${CALLIS_HOST}:${CALLIS_PORT}." >&2
         echo "Ensure the server is reachable and run 'callis setup' again." >&2
         return 1
@@ -140,6 +173,7 @@ _callis_list() {
     fi
     ssh -i "$CALLIS_KEY" -p "$CALLIS_PORT" \
         -o BatchMode=yes -o StrictHostKeyChecking=yes \
+        -o GlobalKnownHostsFile=/dev/null \
         -o UserKnownHostsFile="${CALLIS_CONFIG_DIR}/known_hosts" \
         "${CALLIS_USER}@${CALLIS_HOST}" list
 }
@@ -169,6 +203,7 @@ _callis_connect() {
 
     DEST=$(ssh -i "$CALLIS_KEY" -p "$CALLIS_PORT" \
         -o BatchMode=yes -o StrictHostKeyChecking=yes \
+        -o GlobalKnownHostsFile=/dev/null \
         -o UserKnownHostsFile="${CALLIS_CONFIG_DIR}/known_hosts" \
         "${CALLIS_USER}@${CALLIS_HOST}" "resolve ${TAG}" 2>"$STDERR_TMP")
 
@@ -190,10 +225,11 @@ _callis_connect() {
     TARGET_HOST=$(echo "$DEST" | awk '{print $1}')
     TARGET_PORT=$(echo "$DEST" | awk '{print $2}')
 
-    PROXY_COMMAND="ssh -i \"$CALLIS_KEY\" -p \"$CALLIS_PORT\" -o BatchMode=yes -o StrictHostKeyChecking=yes -o UserKnownHostsFile=\"${CALLIS_CONFIG_DIR}/known_hosts\" -W %h:%p \"${CALLIS_USER}@${CALLIS_HOST}\""
+    PROXY_COMMAND="ssh -i \"$CALLIS_KEY\" -p \"$CALLIS_PORT\" -o BatchMode=yes -o StrictHostKeyChecking=yes -o GlobalKnownHostsFile=/dev/null -o UserKnownHostsFile=\"${CALLIS_CONFIG_DIR}/known_hosts\" -W %h:%p \"${CALLIS_USER}@${CALLIS_HOST}\""
 
     ssh -i "$CALLIS_KEY" \
         -o BatchMode=yes -o StrictHostKeyChecking=yes \
+        -o GlobalKnownHostsFile=/dev/null \
         -o "UserKnownHostsFile=${HOME}/.ssh/known_hosts" \
         -o "ProxyCommand=${PROXY_COMMAND}" \
         -p "$TARGET_PORT" "$@" \

From 2d881e0b97c31be9071058a7d154b94680b89dce Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Tue, 7 Apr 2026 23:00:56 +0000
Subject: [PATCH 05/17] fix: mktemp for tmp known_hosts; checked mv/chmod;
 deferred success msg; POSIX sq escaping for ProxyCommand

Agent-Logs-Url: https://github.com/pacnpal/callis/sessions/c9f63a0e-425a-40dc-a640-d3832bb9df40

Co-authored-by: pacnpal <183241239+pacnpal@users.noreply.github.com>
---
 api/static/callis.sh | 47 ++++++++++++++++++++++++++++++++++++--------
 1 file changed, 39 insertions(+), 8 deletions(-)

diff --git a/api/static/callis.sh b/api/static/callis.sh
index 15a4a77..9fb8678 100755
--- a/api/static/callis.sh
+++ b/api/static/callis.sh
@@ -78,16 +78,24 @@ _callis_setup() {
     } > "$CALLIS_CONFIG_FILE"
     chmod 600 "$CALLIS_CONFIG_FILE"
 
-    echo "Configuration saved to ${CALLIS_CONFIG_FILE}"
+    echo "Configuration written to ${CALLIS_CONFIG_FILE}; verifying SSH host key before setup is finalized."
 
     # Fetch the SSH host key, show its fingerprint, and require explicit user
     # confirmation before trusting it for future connections.
     KNOWN_HOSTS_FILE="${CALLIS_CONFIG_DIR}/known_hosts"
-    TMP_KNOWN_HOSTS_FILE="${KNOWN_HOSTS_FILE}.tmp.$$"
+    TMP_KNOWN_HOSTS_FILE=$(mktemp "${KNOWN_HOSTS_FILE}.tmp.XXXXXX") || {
+        rm -f "$CALLIS_CONFIG_FILE"
+        echo "Error: could not create temporary known_hosts file." >&2
+        return 1
+    }
     printf "Fetching SSH host key from %s:%s...\n" "$CALLIS_HOST" "$CALLIS_PORT"
     FETCHED=$(ssh-keyscan -T 10 -p "$CALLIS_PORT" -t ed25519 "$CALLIS_HOST" 2>/dev/null)
     if [ -n "$FETCHED" ]; then
-        printf '%s\n' "$FETCHED" > "$TMP_KNOWN_HOSTS_FILE"
+        if ! printf '%s\n' "$FETCHED" > "$TMP_KNOWN_HOSTS_FILE"; then
+            rm -f "$TMP_KNOWN_HOSTS_FILE" "$CALLIS_CONFIG_FILE"
+            echo "Error: could not write SSH host key to temporary file." >&2
+            return 1
+        fi
         FINGERPRINT=$(ssh-keygen -lf "$TMP_KNOWN_HOSTS_FILE" 2>/dev/null)
         if [ -z "$FINGERPRINT" ]; then
             rm -f "$TMP_KNOWN_HOSTS_FILE" "$CALLIS_CONFIG_FILE"
@@ -117,11 +125,19 @@ _callis_setup() {
             fi
         fi
 
-        mv "$TMP_KNOWN_HOSTS_FILE" "$KNOWN_HOSTS_FILE"
-        chmod 600 "$KNOWN_HOSTS_FILE"
-        echo "Host key saved."
+        if ! mv "$TMP_KNOWN_HOSTS_FILE" "$KNOWN_HOSTS_FILE"; then
+            rm -f "$TMP_KNOWN_HOSTS_FILE" "$CALLIS_CONFIG_FILE"
+            echo "Error: could not save SSH host key to ${KNOWN_HOSTS_FILE}." >&2
+            return 1
+        fi
+        if ! chmod 600 "$KNOWN_HOSTS_FILE"; then
+            rm -f "$KNOWN_HOSTS_FILE" "$CALLIS_CONFIG_FILE"
+            echo "Error: could not set permissions on ${KNOWN_HOSTS_FILE}." >&2
+            return 1
+        fi
+        echo "Setup complete. Configuration and host key saved."
     else
-        rm -f "$CALLIS_CONFIG_FILE"
+        rm -f "$TMP_KNOWN_HOSTS_FILE" "$CALLIS_CONFIG_FILE"
         echo "Error: could not fetch SSH host key from ${CALLIS_HOST}:${CALLIS_PORT}." >&2
         echo "Ensure the server is reachable and run 'callis setup' again." >&2
         return 1
@@ -165,6 +181,13 @@ _callis_has_known_hosts_entries() {
     grep -Eq '^[[:space:]]*[^#[:space:]]' "$known_hosts_file"
 }
 
+# POSIX single-quote escaping: wraps the argument in single quotes and escapes
+# any embedded single quotes so the result is safe for shell evaluation (e.g.,
+# inside a ProxyCommand string that OpenSSH passes to a shell).
+_callis_sq() {
+    printf '%s' "$1" | sed "s/'/'\\''/g; s/^/'/; s/\$/'/"
+}
+
 _callis_list() {
     _callis_load_config || return 1
     if ! _callis_has_known_hosts_entries "${CALLIS_CONFIG_DIR}/known_hosts"; then
@@ -225,7 +248,15 @@ _callis_connect() {
     TARGET_HOST=$(echo "$DEST" | awk '{print $1}')
     TARGET_PORT=$(echo "$DEST" | awk '{print $2}')
 
-    PROXY_COMMAND="ssh -i \"$CALLIS_KEY\" -p \"$CALLIS_PORT\" -o BatchMode=yes -o StrictHostKeyChecking=yes -o GlobalKnownHostsFile=/dev/null -o UserKnownHostsFile=\"${CALLIS_CONFIG_DIR}/known_hosts\" -W %h:%p \"${CALLIS_USER}@${CALLIS_HOST}\""
+    # Build ProxyCommand using POSIX single-quote escaping so user-controlled
+    # values (key path, port, username, hostname) cannot inject shell metacharacters
+    # when OpenSSH evaluates the command string.
+    _escaped_key=$(_callis_sq "$CALLIS_KEY")
+    _escaped_port=$(_callis_sq "$CALLIS_PORT")
+    _escaped_user=$(_callis_sq "$CALLIS_USER")
+    _escaped_host=$(_callis_sq "$CALLIS_HOST")
+    _escaped_known=$(_callis_sq "${CALLIS_CONFIG_DIR}/known_hosts")
+    PROXY_COMMAND="ssh -i ${_escaped_key} -p ${_escaped_port} -o BatchMode=yes -o StrictHostKeyChecking=yes -o GlobalKnownHostsFile=/dev/null -o UserKnownHostsFile=${_escaped_known} -W %h:%p ${_escaped_user}@${_escaped_host}"
 
     ssh -i "$CALLIS_KEY" \
         -o BatchMode=yes -o StrictHostKeyChecking=yes \

From 4e951b6e574095f2c90c1c1ccf64e6c61902a50e Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Tue, 7 Apr 2026 23:36:48 +0000
Subject: [PATCH 06/17] fix: stderr for abort messages; validate
 TARGET_HOST/PORT; quote %h:%p in ProxyCommand

Agent-Logs-Url: https://github.com/pacnpal/callis/sessions/1b43c896-e52f-4e14-8d18-076255dc991f

Co-authored-by: pacnpal <183241239+pacnpal@users.noreply.github.com>
---
 api/static/callis.sh | 26 ++++++++++++++++++++++----
 1 file changed, 22 insertions(+), 4 deletions(-)

diff --git a/api/static/callis.sh b/api/static/callis.sh
index 9fb8678..5368e27 100755
--- a/api/static/callis.sh
+++ b/api/static/callis.sh
@@ -110,7 +110,7 @@ _callis_setup() {
         read -r TRUST_HOST_KEY
         if [ "$TRUST_HOST_KEY" != "yes" ]; then
             rm -f "$TMP_KNOWN_HOSTS_FILE" "$CALLIS_CONFIG_FILE"
-            echo "Host key was not saved. Setup aborted."
+            echo "Host key was not saved. Setup aborted." >&2
             return 1
         fi
 
@@ -120,7 +120,7 @@ _callis_setup() {
             read -r OVERWRITE_KNOWN_HOSTS
             if [ "$OVERWRITE_KNOWN_HOSTS" != "yes" ]; then
                 rm -f "$TMP_KNOWN_HOSTS_FILE" "$CALLIS_CONFIG_FILE"
-                echo "Existing host key was left unchanged. Setup aborted."
+                echo "Existing host key was left unchanged. Setup aborted." >&2
                 return 1
             fi
         fi
@@ -248,15 +248,33 @@ _callis_connect() {
     TARGET_HOST=$(echo "$DEST" | awk '{print $1}')
     TARGET_PORT=$(echo "$DEST" | awk '{print $2}')
 
+    # Validate bastion-supplied TARGET_HOST and TARGET_PORT to prevent shell
+    # injection via OpenSSH's %h/%p substitution in ProxyCommand.
+    case "$TARGET_HOST" in
+        ''|*[!A-Za-z0-9._:-]*)
+            echo "Error: bastion returned an invalid target host" >&2
+            return 1 ;;
+    esac
+    case "$TARGET_PORT" in
+        ''|*[!0-9]*)
+            echo "Error: bastion returned an invalid target port" >&2
+            return 1 ;;
+    esac
+    if [ "$TARGET_PORT" -lt 1 ] || [ "$TARGET_PORT" -gt 65535 ]; then
+        echo "Error: bastion returned an invalid target port" >&2
+        return 1
+    fi
+
     # Build ProxyCommand using POSIX single-quote escaping so user-controlled
     # values (key path, port, username, hostname) cannot inject shell metacharacters
-    # when OpenSSH evaluates the command string.
+    # when OpenSSH evaluates the command string. Quote %h:%p as a single shell
+    # argument so OpenSSH substitution cannot introduce shell syntax.
     _escaped_key=$(_callis_sq "$CALLIS_KEY")
     _escaped_port=$(_callis_sq "$CALLIS_PORT")
     _escaped_user=$(_callis_sq "$CALLIS_USER")
     _escaped_host=$(_callis_sq "$CALLIS_HOST")
     _escaped_known=$(_callis_sq "${CALLIS_CONFIG_DIR}/known_hosts")
-    PROXY_COMMAND="ssh -i ${_escaped_key} -p ${_escaped_port} -o BatchMode=yes -o StrictHostKeyChecking=yes -o GlobalKnownHostsFile=/dev/null -o UserKnownHostsFile=${_escaped_known} -W %h:%p ${_escaped_user}@${_escaped_host}"
+    PROXY_COMMAND="ssh -i ${_escaped_key} -p ${_escaped_port} -o BatchMode=yes -o StrictHostKeyChecking=yes -o GlobalKnownHostsFile=/dev/null -o UserKnownHostsFile=${_escaped_known} -W '%h:%p' ${_escaped_user}@${_escaped_host}"
 
     ssh -i "$CALLIS_KEY" \
         -o BatchMode=yes -o StrictHostKeyChecking=yes \

From 5113bc9b93e12634dc3ad6a3381e39ffbe52de7b Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Tue, 7 Apr 2026 23:37:44 +0000
Subject: [PATCH 07/17] fix: tighten TARGET_HOST charset; reject leading-zero
 TARGET_PORT before range check

Agent-Logs-Url: https://github.com/pacnpal/callis/sessions/1b43c896-e52f-4e14-8d18-076255dc991f

Co-authored-by: pacnpal <183241239+pacnpal@users.noreply.github.com>
---
 api/static/callis.sh | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/api/static/callis.sh b/api/static/callis.sh
index 5368e27..51527e2 100755
--- a/api/static/callis.sh
+++ b/api/static/callis.sh
@@ -251,12 +251,12 @@ _callis_connect() {
     # Validate bastion-supplied TARGET_HOST and TARGET_PORT to prevent shell
     # injection via OpenSSH's %h/%p substitution in ProxyCommand.
     case "$TARGET_HOST" in
-        ''|*[!A-Za-z0-9._:-]*)
+        ''|*[!A-Za-z0-9.-]*)
             echo "Error: bastion returned an invalid target host" >&2
             return 1 ;;
     esac
     case "$TARGET_PORT" in
-        ''|*[!0-9]*)
+        ''|*[!0-9]*|0[0-9]*)
             echo "Error: bastion returned an invalid target port" >&2
             return 1 ;;
     esac

From b0bba361885694c803c0218e8bf53f1c1d1ef75d Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Wed, 8 Apr 2026 00:08:14 +0000
Subject: [PATCH 08/17] fix: write config via temp file + atomic mv; check
 write and chmod return codes

Agent-Logs-Url: https://github.com/pacnpal/callis/sessions/9554d4ab-0e49-4a70-b8bf-5d991e04cc12

Co-authored-by: pacnpal <183241239+pacnpal@users.noreply.github.com>
---
 api/static/callis.sh | 28 ++++++++++++++++++++++------
 1 file changed, 22 insertions(+), 6 deletions(-)

diff --git a/api/static/callis.sh b/api/static/callis.sh
index 51527e2..2d3511c 100755
--- a/api/static/callis.sh
+++ b/api/static/callis.sh
@@ -69,16 +69,32 @@ _callis_setup() {
     read -r CALLIS_KEY
     CALLIS_KEY="${CALLIS_KEY:-$HOME/.ssh/id_ed25519}"
 
-    # Write values as plain key=value pairs (not sourced — parsed safely below)
-    {
+    # Write values as plain key=value pairs (not sourced — parsed safely below).
+    # Use a temp file + atomic mv so a failed write never leaves a partial config.
+    TMP_CONFIG_FILE=$(mktemp "${CALLIS_CONFIG_FILE}.tmp.XXXXXX") || {
+        echo "Error: could not create temporary config file." >&2
+        return 1
+    }
+    if ! {
         printf 'CALLIS_HOST=%s\n' "$CALLIS_HOST"
         printf 'CALLIS_PORT=%s\n' "$CALLIS_PORT"
         printf 'CALLIS_USER=%s\n' "$CALLIS_USER"
         printf 'CALLIS_KEY=%s\n'  "$CALLIS_KEY"
-    } > "$CALLIS_CONFIG_FILE"
-    chmod 600 "$CALLIS_CONFIG_FILE"
-
-    echo "Configuration written to ${CALLIS_CONFIG_FILE}; verifying SSH host key before setup is finalized."
+    } > "$TMP_CONFIG_FILE"; then
+        rm -f "$TMP_CONFIG_FILE"
+        echo "Error: could not write configuration to temporary file." >&2
+        return 1
+    fi
+    if ! chmod 600 "$TMP_CONFIG_FILE"; then
+        rm -f "$TMP_CONFIG_FILE"
+        echo "Error: could not set permissions on temporary config file." >&2
+        return 1
+    fi
+    if ! mv "$TMP_CONFIG_FILE" "$CALLIS_CONFIG_FILE"; then
+        rm -f "$TMP_CONFIG_FILE"
+        echo "Error: could not save configuration to ${CALLIS_CONFIG_FILE}." >&2
+        return 1
+    fi
 
     # Fetch the SSH host key, show its fingerprint, and require explicit user
     # confirmation before trusting it for future connections.

From 78b5aef20eb545a5ed1399c264e76d75f099f7a7 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Wed, 8 Apr 2026 12:12:26 +0000
Subject: [PATCH 09/17] fix: defer config mv until after host key committed;
 allow underscores in TARGET_HOST

Agent-Logs-Url: https://github.com/pacnpal/callis/sessions/e1b2d303-8866-4547-b5bc-c0ba4a2773af

Co-authored-by: pacnpal <183241239+pacnpal@users.noreply.github.com>
---
 api/static/callis.sh | 32 ++++++++++++++++++--------------
 1 file changed, 18 insertions(+), 14 deletions(-)

diff --git a/api/static/callis.sh b/api/static/callis.sh
index 2d3511c..c4e5e04 100755
--- a/api/static/callis.sh
+++ b/api/static/callis.sh
@@ -90,17 +90,14 @@ _callis_setup() {
         echo "Error: could not set permissions on temporary config file." >&2
         return 1
     fi
-    if ! mv "$TMP_CONFIG_FILE" "$CALLIS_CONFIG_FILE"; then
-        rm -f "$TMP_CONFIG_FILE"
-        echo "Error: could not save configuration to ${CALLIS_CONFIG_FILE}." >&2
-        return 1
-    fi
 
     # Fetch the SSH host key, show its fingerprint, and require explicit user
     # confirmation before trusting it for future connections.
+    # The config temp file is not committed until both files are ready so that
+    # aborting or failing here never overwrites a previously working config.
     KNOWN_HOSTS_FILE="${CALLIS_CONFIG_DIR}/known_hosts"
     TMP_KNOWN_HOSTS_FILE=$(mktemp "${KNOWN_HOSTS_FILE}.tmp.XXXXXX") || {
-        rm -f "$CALLIS_CONFIG_FILE"
+        rm -f "$TMP_CONFIG_FILE"
         echo "Error: could not create temporary known_hosts file." >&2
         return 1
     }
@@ -108,13 +105,13 @@ _callis_setup() {
     FETCHED=$(ssh-keyscan -T 10 -p "$CALLIS_PORT" -t ed25519 "$CALLIS_HOST" 2>/dev/null)
     if [ -n "$FETCHED" ]; then
         if ! printf '%s\n' "$FETCHED" > "$TMP_KNOWN_HOSTS_FILE"; then
-            rm -f "$TMP_KNOWN_HOSTS_FILE" "$CALLIS_CONFIG_FILE"
+            rm -f "$TMP_KNOWN_HOSTS_FILE" "$TMP_CONFIG_FILE"
             echo "Error: could not write SSH host key to temporary file." >&2
             return 1
         fi
         FINGERPRINT=$(ssh-keygen -lf "$TMP_KNOWN_HOSTS_FILE" 2>/dev/null)
         if [ -z "$FINGERPRINT" ]; then
-            rm -f "$TMP_KNOWN_HOSTS_FILE" "$CALLIS_CONFIG_FILE"
+            rm -f "$TMP_KNOWN_HOSTS_FILE" "$TMP_CONFIG_FILE"
             echo "Error: could not compute SSH host key fingerprint for ${CALLIS_HOST}:${CALLIS_PORT}." >&2
             return 1
         fi
@@ -125,7 +122,7 @@ _callis_setup() {
         printf "Trust and save this host key? Type 'yes' to continue: "
         read -r TRUST_HOST_KEY
         if [ "$TRUST_HOST_KEY" != "yes" ]; then
-            rm -f "$TMP_KNOWN_HOSTS_FILE" "$CALLIS_CONFIG_FILE"
+            rm -f "$TMP_KNOWN_HOSTS_FILE" "$TMP_CONFIG_FILE"
             echo "Host key was not saved. Setup aborted." >&2
             return 1
         fi
@@ -135,25 +132,32 @@ _callis_setup() {
             printf "Type 'yes' to overwrite the existing Callis host key: "
             read -r OVERWRITE_KNOWN_HOSTS
             if [ "$OVERWRITE_KNOWN_HOSTS" != "yes" ]; then
-                rm -f "$TMP_KNOWN_HOSTS_FILE" "$CALLIS_CONFIG_FILE"
+                rm -f "$TMP_KNOWN_HOSTS_FILE" "$TMP_CONFIG_FILE"
                 echo "Existing host key was left unchanged. Setup aborted." >&2
                 return 1
             fi
         fi
 
         if ! mv "$TMP_KNOWN_HOSTS_FILE" "$KNOWN_HOSTS_FILE"; then
-            rm -f "$TMP_KNOWN_HOSTS_FILE" "$CALLIS_CONFIG_FILE"
+            rm -f "$TMP_KNOWN_HOSTS_FILE" "$TMP_CONFIG_FILE"
             echo "Error: could not save SSH host key to ${KNOWN_HOSTS_FILE}." >&2
             return 1
         fi
         if ! chmod 600 "$KNOWN_HOSTS_FILE"; then
-            rm -f "$KNOWN_HOSTS_FILE" "$CALLIS_CONFIG_FILE"
+            rm -f "$KNOWN_HOSTS_FILE" "$TMP_CONFIG_FILE"
             echo "Error: could not set permissions on ${KNOWN_HOSTS_FILE}." >&2
             return 1
         fi
+        # Both files are ready — atomically commit the config last so that
+        # any earlier abort leaves the previous config intact.
+        if ! mv "$TMP_CONFIG_FILE" "$CALLIS_CONFIG_FILE"; then
+            rm -f "$TMP_CONFIG_FILE" "$KNOWN_HOSTS_FILE"
+            echo "Error: could not save configuration to ${CALLIS_CONFIG_FILE}." >&2
+            return 1
+        fi
         echo "Setup complete. Configuration and host key saved."
     else
-        rm -f "$TMP_KNOWN_HOSTS_FILE" "$CALLIS_CONFIG_FILE"
+        rm -f "$TMP_KNOWN_HOSTS_FILE" "$TMP_CONFIG_FILE"
         echo "Error: could not fetch SSH host key from ${CALLIS_HOST}:${CALLIS_PORT}." >&2
         echo "Ensure the server is reachable and run 'callis setup' again." >&2
         return 1
@@ -267,7 +271,7 @@ _callis_connect() {
     # Validate bastion-supplied TARGET_HOST and TARGET_PORT to prevent shell
     # injection via OpenSSH's %h/%p substitution in ProxyCommand.
     case "$TARGET_HOST" in
-        ''|*[!A-Za-z0-9.-]*)
+        ''|*[!A-Za-z0-9._-]*)
             echo "Error: bastion returned an invalid target host" >&2
             return 1 ;;
     esac

From 446ac01813cfd87cb51c0d48d4c7710b745c5b91 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Wed, 8 Apr 2026 12:26:44 +0000
Subject: [PATCH 10/17] fix: use -f for known_hosts overwrite check;
 backup/restore known_hosts for atomic setup

Agent-Logs-Url: https://github.com/pacnpal/callis/sessions/6592ac9d-1ccd-4ec6-bb48-431d91ea065e

Co-authored-by: pacnpal <183241239+pacnpal@users.noreply.github.com>
---
 api/static/callis.sh | 39 +++++++++++++++++++++++++++++++++++----
 1 file changed, 35 insertions(+), 4 deletions(-)

diff --git a/api/static/callis.sh b/api/static/callis.sh
index c4e5e04..a6f5cbd 100755
--- a/api/static/callis.sh
+++ b/api/static/callis.sh
@@ -127,7 +127,9 @@ _callis_setup() {
             return 1
         fi
 
-        if [ -s "$KNOWN_HOSTS_FILE" ]; then
+        # Use -f (existence) not -s (non-empty) so empty or corrupt files also
+        # trigger the overwrite confirmation and are not silently replaced.
+        if [ -f "$KNOWN_HOSTS_FILE" ]; then
             echo "Warning: ${KNOWN_HOSTS_FILE} already exists and will be replaced."
             printf "Type 'yes' to overwrite the existing Callis host key: "
             read -r OVERWRITE_KNOWN_HOSTS
@@ -138,23 +140,52 @@ _callis_setup() {
             fi
         fi
 
+        # Back up the existing known_hosts so it can be restored if the final
+        # config commit fails, ensuring no partial state is left on disk.
+        BACKUP_KNOWN_HOSTS=""
+        if [ -f "$KNOWN_HOSTS_FILE" ]; then
+            BACKUP_KNOWN_HOSTS=$(mktemp "${KNOWN_HOSTS_FILE}.bak.XXXXXX") || {
+                rm -f "$TMP_KNOWN_HOSTS_FILE" "$TMP_CONFIG_FILE"
+                echo "Error: could not create backup of existing known_hosts." >&2
+                return 1
+            }
+            if ! cp "$KNOWN_HOSTS_FILE" "$BACKUP_KNOWN_HOSTS"; then
+                rm -f "$TMP_KNOWN_HOSTS_FILE" "$TMP_CONFIG_FILE" "$BACKUP_KNOWN_HOSTS"
+                echo "Error: could not back up existing known_hosts." >&2
+                return 1
+            fi
+        fi
+
         if ! mv "$TMP_KNOWN_HOSTS_FILE" "$KNOWN_HOSTS_FILE"; then
-            rm -f "$TMP_KNOWN_HOSTS_FILE" "$TMP_CONFIG_FILE"
+            rm -f "$TMP_KNOWN_HOSTS_FILE" "$TMP_CONFIG_FILE" "$BACKUP_KNOWN_HOSTS"
             echo "Error: could not save SSH host key to ${KNOWN_HOSTS_FILE}." >&2
             return 1
         fi
         if ! chmod 600 "$KNOWN_HOSTS_FILE"; then
-            rm -f "$KNOWN_HOSTS_FILE" "$TMP_CONFIG_FILE"
+            if [ -n "$BACKUP_KNOWN_HOSTS" ]; then
+                mv "$BACKUP_KNOWN_HOSTS" "$KNOWN_HOSTS_FILE" || \
+                    echo "Warning: could not restore previous known_hosts from ${BACKUP_KNOWN_HOSTS}." >&2
+            else
+                rm -f "$KNOWN_HOSTS_FILE"
+            fi
+            rm -f "$TMP_CONFIG_FILE"
             echo "Error: could not set permissions on ${KNOWN_HOSTS_FILE}." >&2
             return 1
         fi
         # Both files are ready — atomically commit the config last so that
         # any earlier abort leaves the previous config intact.
         if ! mv "$TMP_CONFIG_FILE" "$CALLIS_CONFIG_FILE"; then
-            rm -f "$TMP_CONFIG_FILE" "$KNOWN_HOSTS_FILE"
+            if [ -n "$BACKUP_KNOWN_HOSTS" ]; then
+                mv "$BACKUP_KNOWN_HOSTS" "$KNOWN_HOSTS_FILE" || \
+                    echo "Warning: could not restore previous known_hosts from ${BACKUP_KNOWN_HOSTS}." >&2
+            else
+                rm -f "$KNOWN_HOSTS_FILE"
+            fi
+            rm -f "$TMP_CONFIG_FILE"
             echo "Error: could not save configuration to ${CALLIS_CONFIG_FILE}." >&2
             return 1
         fi
+        rm -f "$BACKUP_KNOWN_HOSTS"
         echo "Setup complete. Configuration and host key saved."
     else
         rm -f "$TMP_KNOWN_HOSTS_FILE" "$TMP_CONFIG_FILE"

From 24ffa05c2dd84bb94b829c1e954d71df61ea3f79 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Wed, 8 Apr 2026 12:43:56 +0000
Subject: [PATCH 11/17] fix: guard BACKUP_KNOWN_HOSTS rm calls with non-empty
 check

When no prior known_hosts exists, BACKUP_KNOWN_HOSTS is empty string.
Calling `rm -f ""` is non-portable and may emit diagnostics or return
non-zero on some platforms. Guard both the mv-failure cleanup path and
the post-success cleanup with `[ -n "$BACKUP_KNOWN_HOSTS" ]` before
invoking rm.

Agent-Logs-Url: https://github.com/pacnpal/callis/sessions/09fd8773-d243-4801-b931-b4b54d9da5e2

Co-authored-by: pacnpal <183241239+pacnpal@users.noreply.github.com>
---
 api/static/callis.sh | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/api/static/callis.sh b/api/static/callis.sh
index a6f5cbd..d34018e 100755
--- a/api/static/callis.sh
+++ b/api/static/callis.sh
@@ -157,7 +157,11 @@ _callis_setup() {
         fi
 
         if ! mv "$TMP_KNOWN_HOSTS_FILE" "$KNOWN_HOSTS_FILE"; then
-            rm -f "$TMP_KNOWN_HOSTS_FILE" "$TMP_CONFIG_FILE" "$BACKUP_KNOWN_HOSTS"
+            if [ -n "$BACKUP_KNOWN_HOSTS" ]; then
+                rm -f "$TMP_KNOWN_HOSTS_FILE" "$TMP_CONFIG_FILE" "$BACKUP_KNOWN_HOSTS"
+            else
+                rm -f "$TMP_KNOWN_HOSTS_FILE" "$TMP_CONFIG_FILE"
+            fi
             echo "Error: could not save SSH host key to ${KNOWN_HOSTS_FILE}." >&2
             return 1
         fi
@@ -185,7 +189,9 @@ _callis_setup() {
             echo "Error: could not save configuration to ${CALLIS_CONFIG_FILE}." >&2
             return 1
         fi
-        rm -f "$BACKUP_KNOWN_HOSTS"
+        if [ -n "$BACKUP_KNOWN_HOSTS" ]; then
+            rm -f "$BACKUP_KNOWN_HOSTS"
+        fi
         echo "Setup complete. Configuration and host key saved."
     else
         rm -f "$TMP_KNOWN_HOSTS_FILE" "$TMP_CONFIG_FILE"

From 41e8f949150a4f71fc1229e4bd63573e6a8e6898 Mon Sep 17 00:00:00 2001
From: pacnpal <183241239+pacnpal@users.noreply.github.com>
Date: Wed, 8 Apr 2026 08:49:08 -0400
Subject: [PATCH 12/17] Update api/static/callis.sh

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
---
 api/static/callis.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/api/static/callis.sh b/api/static/callis.sh
index d34018e..cc3a582 100755
--- a/api/static/callis.sh
+++ b/api/static/callis.sh
@@ -242,7 +242,7 @@ _callis_has_known_hosts_entries() {
 # any embedded single quotes so the result is safe for shell evaluation (e.g.,
 # inside a ProxyCommand string that OpenSSH passes to a shell).
 _callis_sq() {
-    printf '%s' "$1" | sed "s/'/'\\''/g; s/^/'/; s/\$/'/"
+    printf '%s' "$1" | sed "s/'/'\\''/g; s/^/'/; s/$/'/"
 }
 
 _callis_list() {

From 964702198e07cad7268962fea6dcf0dd52f1d62c Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Wed, 8 Apr 2026 12:58:23 +0000
Subject: [PATCH 13/17] fix: move $@ before security options in _callis_connect
 to prevent override

Agent-Logs-Url: https://github.com/pacnpal/callis/sessions/a32dff90-e869-490d-8b9c-ac00d22f9883

Co-authored-by: pacnpal <183241239+pacnpal@users.noreply.github.com>
---
 api/static/callis.sh | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/api/static/callis.sh b/api/static/callis.sh
index cc3a582..df6269d 100755
--- a/api/static/callis.sh
+++ b/api/static/callis.sh
@@ -333,11 +333,14 @@ _callis_connect() {
     _escaped_known=$(_callis_sq "${CALLIS_CONFIG_DIR}/known_hosts")
     PROXY_COMMAND="ssh -i ${_escaped_key} -p ${_escaped_port} -o BatchMode=yes -o StrictHostKeyChecking=yes -o GlobalKnownHostsFile=/dev/null -o UserKnownHostsFile=${_escaped_known} -W '%h:%p' ${_escaped_user}@${_escaped_host}"
 
-    ssh -i "$CALLIS_KEY" \
+    # Pass $@ before the enforced options so user-supplied flags (e.g. -v)
+    # are accepted but cannot override the security settings that follow.
+    ssh "$@" \
+        -i "$CALLIS_KEY" \
+        -p "$TARGET_PORT" \
         -o BatchMode=yes -o StrictHostKeyChecking=yes \
         -o GlobalKnownHostsFile=/dev/null \
         -o "UserKnownHostsFile=${HOME}/.ssh/known_hosts" \
         -o "ProxyCommand=${PROXY_COMMAND}" \
-        -p "$TARGET_PORT" "$@" \
         "${CALLIS_USER}@${TARGET_HOST}"
 }

From 5ff08830c78683f5ed0efe90a47558d37564b90e Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Wed, 8 Apr 2026 13:52:31 +0000
Subject: [PATCH 14/17] fix: validate CALLIS_HOST/PORT before ssh-keyscan;
 split $@ into flags+remote-cmd in connect

Agent-Logs-Url: https://github.com/pacnpal/callis/sessions/52cd6852-79eb-455c-9e07-189f7063a62b

Co-authored-by: pacnpal <183241239+pacnpal@users.noreply.github.com>
---
 api/static/callis.sh | 87 +++++++++++++++++++++++++++++++++++++++-----
 1 file changed, 78 insertions(+), 9 deletions(-)

diff --git a/api/static/callis.sh b/api/static/callis.sh
index df6269d..a4bacac 100755
--- a/api/static/callis.sh
+++ b/api/static/callis.sh
@@ -56,9 +56,27 @@ _callis_setup() {
         echo "Error: hostname is required." >&2
         return 1
     fi
+    # Reject hostnames that start with '-' (would be parsed as options by
+    # ssh-keyscan/ssh) or contain whitespace (not valid in a hostname).
+    case "$CALLIS_HOST" in
+        -*|*' '*|*'	'*)
+            echo "Error: invalid hostname — must not start with '-' or contain whitespace." >&2
+            return 1 ;;
+    esac
     printf "Callis SSH port [2222]: "
     read -r CALLIS_PORT
     CALLIS_PORT="${CALLIS_PORT:-2222}"
+    # Validate port: must be a plain positive integer in range 1-65535 with no
+    # leading zeros (which could be misinterpreted as octal on some systems).
+    case "$CALLIS_PORT" in
+        ''|*[!0-9]*|0[0-9]*)
+            echo "Error: invalid port — must be a positive number with no leading zeros." >&2
+            return 1 ;;
+    esac
+    if [ "$CALLIS_PORT" -lt 1 ] || [ "$CALLIS_PORT" -gt 65535 ]; then
+        echo "Error: invalid port — must be between 1 and 65535." >&2
+        return 1
+    fi
     printf "Your Callis username: "
     read -r CALLIS_USER
     if [ -z "$CALLIS_USER" ]; then
@@ -102,7 +120,7 @@ _callis_setup() {
         return 1
     }
     printf "Fetching SSH host key from %s:%s...\n" "$CALLIS_HOST" "$CALLIS_PORT"
-    FETCHED=$(ssh-keyscan -T 10 -p "$CALLIS_PORT" -t ed25519 "$CALLIS_HOST" 2>/dev/null)
+    FETCHED=$(ssh-keyscan -T 10 -p "$CALLIS_PORT" -t ed25519 -- "$CALLIS_HOST" 2>/dev/null)
     if [ -n "$FETCHED" ]; then
         if ! printf '%s\n' "$FETCHED" > "$TMP_KNOWN_HOSTS_FILE"; then
             rm -f "$TMP_KNOWN_HOSTS_FILE" "$TMP_CONFIG_FILE"
@@ -333,14 +351,65 @@ _callis_connect() {
     _escaped_known=$(_callis_sq "${CALLIS_CONFIG_DIR}/known_hosts")
     PROXY_COMMAND="ssh -i ${_escaped_key} -p ${_escaped_port} -o BatchMode=yes -o StrictHostKeyChecking=yes -o GlobalKnownHostsFile=/dev/null -o UserKnownHostsFile=${_escaped_known} -W '%h:%p' ${_escaped_user}@${_escaped_host}"
 
-    # Pass $@ before the enforced options so user-supplied flags (e.g. -v)
-    # are accepted but cannot override the security settings that follow.
-    ssh "$@" \
-        -i "$CALLIS_KEY" \
+    # Separate user-supplied SSH option flags from any trailing remote command.
+    # Leading args that begin with '-' (including their next-arg values for
+    # options that require them) are treated as SSH flags and placed after the
+    # enforced security options below.  The first non-flag arg (or any args
+    # after '--') form the remote command and are placed after the destination.
+    # This means the enforced options always appear first and cannot be
+    # overridden (OpenSSH uses first-occurrence semantics for -o options).
+    #
+    # SSH options that consume the next positional argument as their value:
+    _nflags=0
+    _skip_next=0
+    for _ua in "$@"; do
+        if [ "$_skip_next" -eq 1 ]; then
+            _nflags=$((_nflags + 1)); _skip_next=0; continue
+        fi
+        case "$_ua" in
+            --) break ;;
+            -b|-c|-D|-E|-e|-F|-I|-i|-J|-L|-l|-m|-o|-p|-Q|-R|-S|-w|-W)
+                _nflags=$((_nflags + 1)); _skip_next=1 ;;
+            -*) _nflags=$((_nflags + 1)) ;;
+            *)  break ;;
+        esac
+    done
+
+    # Build single-quoted strings for the flag and command portions so they
+    # can be safely re-split by eval without shell-injection risk.
+    _uf=''
+    _uc=''
+    _ui=0
+    for _ua in "$@"; do
+        _ui=$((_ui + 1))
+        _q=$(_callis_sq "$_ua")
+        if   [ "$_ui" -le "$_nflags" ]; then
+            _uf="${_uf:+$_uf }$_q"
+        elif [ "$_ua" = "--" ] && [ "$_ui" -eq "$((_nflags + 1))" ]; then
+            :   # drop the '--' separator — not needed in the final ssh call
+        else
+            _uc="${_uc:+$_uc }$_q"
+        fi
+    done
+
+    _sq_key=$(_callis_sq "$CALLIS_KEY")
+    _sq_proxy=$(_callis_sq "$PROXY_COMMAND")
+    _sq_dest=$(_callis_sq "${CALLIS_USER}@${TARGET_HOST}")
+    _sq_known=$(_callis_sq "${HOME}/.ssh/known_hosts")
+
+    # Enforced security options come first so they take precedence (first-
+    # occurrence wins in OpenSSH).  User option flags follow, then the fixed
+    # destination, then any user-supplied remote command arguments.
+    # shellcheck disable=SC2086
+    eval ssh \
+        -i "$_sq_key" \
         -p "$TARGET_PORT" \
-        -o BatchMode=yes -o StrictHostKeyChecking=yes \
+        -o BatchMode=yes \
+        -o StrictHostKeyChecking=yes \
         -o GlobalKnownHostsFile=/dev/null \
-        -o "UserKnownHostsFile=${HOME}/.ssh/known_hosts" \
-        -o "ProxyCommand=${PROXY_COMMAND}" \
-        "${CALLIS_USER}@${TARGET_HOST}"
+        -o "UserKnownHostsFile=$_sq_known" \
+        -o "ProxyCommand=$_sq_proxy" \
+        ${_uf} \
+        "$_sq_dest" \
+        ${_uc}
 }

From 2b038ff2b03f6bb59772c46272a9daa9deee9b5b Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Wed, 8 Apr 2026 14:24:14 +0000
Subject: [PATCH 15/17] fix: known_hosts readability check and ssh arg splitter
 for concatenated options

Agent-Logs-Url: https://github.com/pacnpal/callis/sessions/c0b1cb09-5ed0-46a6-9c8e-d12e56a6fc7d

Co-authored-by: pacnpal <183241239+pacnpal@users.noreply.github.com>
---
 api/static/callis.sh | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/api/static/callis.sh b/api/static/callis.sh
index a4bacac..344f6a2 100755
--- a/api/static/callis.sh
+++ b/api/static/callis.sh
@@ -252,8 +252,10 @@ _callis_load_config() {
 
 _callis_has_known_hosts_entries() {
     known_hosts_file="$1"
-    [ -s "$known_hosts_file" ] || return 1
-    grep -Eq '^[[:space:]]*[^#[:space:]]' "$known_hosts_file"
+    # Use -r (readable) instead of -s (non-empty) so unreadable files are
+    # rejected cleanly; the grep handles empty files by returning non-zero.
+    [ -r "$known_hosts_file" ] || return 1
+    grep -Eq '^[[:space:]]*[^#[:space:]]' "$known_hosts_file" 2>/dev/null
 }
 
 # POSIX single-quote escaping: wraps the argument in single quotes and escapes
@@ -368,8 +370,14 @@ _callis_connect() {
         fi
         case "$_ua" in
             --) break ;;
+            # Options that take a next argument as a *separate* token.
+            # When the value is concatenated in the same token (e.g.,
+            # -L8080:host:port or -oStrictHostKeyChecking=yes), the token
+            # length is > 2 and the value is already present, so do NOT
+            # set _skip_next in that case.
             -b|-c|-D|-E|-e|-F|-I|-i|-J|-L|-l|-m|-o|-p|-Q|-R|-S|-w|-W)
-                _nflags=$((_nflags + 1)); _skip_next=1 ;;
+                _nflags=$((_nflags + 1))
+                if [ "${#_ua}" -eq 2 ]; then _skip_next=1; fi ;;
             -*) _nflags=$((_nflags + 1)) ;;
             *)  break ;;
         esac

From 9bf2098d96045dbd012cd39bdfad91a993ca116e Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Wed, 8 Apr 2026 15:45:22 +0000
Subject: [PATCH 16/17] fix: correct _callis_sq sed escaping and move -p after
 user flags in _callis_connect

Agent-Logs-Url: https://github.com/pacnpal/callis/sessions/489cbf93-0d75-4a6c-9cb0-9a362fd0981d

Co-authored-by: pacnpal <183241239+pacnpal@users.noreply.github.com>
---
 api/static/callis.sh | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/api/static/callis.sh b/api/static/callis.sh
index 344f6a2..9c45d50 100755
--- a/api/static/callis.sh
+++ b/api/static/callis.sh
@@ -262,7 +262,7 @@ _callis_has_known_hosts_entries() {
 # any embedded single quotes so the result is safe for shell evaluation (e.g.,
 # inside a ProxyCommand string that OpenSSH passes to a shell).
 _callis_sq() {
-    printf '%s' "$1" | sed "s/'/'\\''/g; s/^/'/; s/$/'/"
+    printf '%s' "$1" | sed "s/'/'\\\\''/g; s/^/'/; s/$/'/"
 }
 
 _callis_list() {
@@ -405,19 +405,22 @@ _callis_connect() {
     _sq_dest=$(_callis_sq "${CALLIS_USER}@${TARGET_HOST}")
     _sq_known=$(_callis_sq "${HOME}/.ssh/known_hosts")
 
-    # Enforced security options come first so they take precedence (first-
-    # occurrence wins in OpenSSH).  User option flags follow, then the fixed
-    # destination, then any user-supplied remote command arguments.
+    # Enforced -o options come first so they take precedence (first-occurrence
+    # wins in OpenSSH for -o flags).  User option flags follow.  -p comes after
+    # user flags because OpenSSH uses last-occurrence semantics for -p, so
+    # placing it last ensures the bastion-resolved target port cannot be
+    # overridden by a user-supplied -p flag.  The fixed destination follows,
+    # then any user-supplied remote command arguments.
     # shellcheck disable=SC2086
     eval ssh \
         -i "$_sq_key" \
-        -p "$TARGET_PORT" \
         -o BatchMode=yes \
         -o StrictHostKeyChecking=yes \
         -o GlobalKnownHostsFile=/dev/null \
         -o "UserKnownHostsFile=$_sq_known" \
         -o "ProxyCommand=$_sq_proxy" \
         ${_uf} \
+        -p "$TARGET_PORT" \
         "$_sq_dest" \
         ${_uc}
 }

From 851a14c4c20a1bda484db993ebc2552372a768c8 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Wed, 8 Apr 2026 16:11:11 +0000
Subject: [PATCH 17/17] fix: replace _callis_sq sed implementation with pure
 POSIX shell

Replaces the double-quoted sed program (which used 4 backslashes \\\\
to produce the correct sed replacement) with a pure POSIX shell
while-loop that splits on ' characters using %% / # parameter
expansion and appends the standard '\'' escape sequence for each
embedded quote. Avoids sed and double-quote backslash counting
entirely, making the escaping logic visually unambiguous.

Adds an inline example in the comment showing that
_callis_sq "it's" produces 'it'\''s' which eval reproduces "it's".

Agent-Logs-Url: https://github.com/pacnpal/callis/sessions/d8e62c33-f356-4385-b5f6-ec47d72d6ae3

Co-authored-by: pacnpal <183241239+pacnpal@users.noreply.github.com>
---
 api/static/callis.sh | 19 +++++++++++++++----
 1 file changed, 15 insertions(+), 4 deletions(-)

diff --git a/api/static/callis.sh b/api/static/callis.sh
index 9c45d50..9181aa0 100755
--- a/api/static/callis.sh
+++ b/api/static/callis.sh
@@ -258,11 +258,22 @@ _callis_has_known_hosts_entries() {
     grep -Eq '^[[:space:]]*[^#[:space:]]' "$known_hosts_file" 2>/dev/null
 }
 
-# POSIX single-quote escaping: wraps the argument in single quotes and escapes
-# any embedded single quotes so the result is safe for shell evaluation (e.g.,
-# inside a ProxyCommand string that OpenSSH passes to a shell).
+# POSIX single-quote escaping: wraps the argument in single quotes and replaces
+# each embedded ' with '\'' (end-quote, backslash-escaped literal quote,
+# reopen-quote) so the result is safe for shell evaluation (e.g., inside a
+# ProxyCommand string that OpenSSH passes to a shell).
+# Example: _callis_sq "it's" produces 'it'\''s' which eval reproduces "it's".
 _callis_sq() {
-    printf '%s' "$1" | sed "s/'/'\\\\''/g; s/^/'/; s/$/'/"
+    _sq_out=''
+    _sq_in="$1"
+    while [ -n "$_sq_in" ]; do
+        _sq_head="${_sq_in%%\'*}"
+        _sq_out="${_sq_out}${_sq_head}"
+        [ "$_sq_in" = "$_sq_head" ] && break
+        _sq_out="${_sq_out}'\\''"
+        _sq_in="${_sq_in#*\'}"
+    done
+    printf "'%s'" "$_sq_out"
 }
 
 _callis_list() {