From 3485e8b9dc5b363a40834f8edf280b49bbfe1358 Mon Sep 17 00:00:00 2001
From: Wesley Darlington <wesley.darlington@gmail.com>
Date: Wed, 18 Nov 2009 12:21:21 +0000
Subject: [PATCH] Clean build, zero functionality. Doesn't fork subprocesses,
 doesn't *do* ssh-agent stuff.

---
 .gitignore |   3 ++
 charade.c  | 134 ++++++++++++++++++++++++++++++++++++++++++++++-------
 cmdline.c  |   3 ++
 3 files changed, 124 insertions(+), 16 deletions(-)
 create mode 100644 .gitignore

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..e650198
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,3 @@
+*.d
+*.o
+charade.exe
diff --git a/charade.c b/charade.c
index 63f9685..4bffa4f 100644
--- a/charade.c
+++ b/charade.c
@@ -5,30 +5,97 @@
  * Copyright (c) 2009, Wesley Darlington. All Rights Reserved.
  */
 
+#include <errno.h>
 #include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <sys/param.h>
+#include <sys/socket.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/un.h>
+#include <unistd.h>
 
 #include "cmdline.h"
 
+#define LISTEN_BACKLOG 5
+
+#define SSH_AUTHSOCKET_ENV_NAME "SSH_AUTH_SOCK"
+#define SSH_AGENTPID_ENV_NAME "SSH_AGENT_PID"
+
 int sock;
 
+char socket_dir[MAXPATHLEN] = "";
+char socket_name[MAXPATHLEN] = "";
+
+int remove_socket_at_exit = 1;
+
+void
+remove_socket_dir(void)  /* atexit handler */
+{
+    if (remove_socket_at_exit) {
+        int ret = rmdir(socket_dir);
+
+        if (ret) {
+            fprintf(stderr, "Error removing socket directory '%s': %s.\n",
+                    socket_dir, strerror(errno));
+            /* atexit! */
+        }
+    }
+}
+
+void
+remove_socket(void)  /* atexit handler */
+{
+    if (remove_socket_at_exit) {
+        int ret = unlink(socket_name);
+
+        if (ret) {
+            fprintf(stderr, "Error removing socket '%s': %s.\n",
+                    socket_name, strerror(errno));
+            /* atexit! */
+        }
+    }
+}
+
 
 void
 create_socket(void)
 {
+#if 0
     if (agentsocket == NULL) {
-        /* Create private directory for agent socket */
-        strlcpy(socket_dir, "/tmp/ssh-XXXXXXXXXX", sizeof socket_dir);
-        if (mkdtemp(socket_dir) == NULL) {
-            perror("mkdtemp: private socket dir");
-            exit(1);
-        }
-        snprintf(socket_name, sizeof socket_name, "%s/agent.%ld", socket_dir,
-            (long)parent_pid);
+#endif
+
+    /* Create private directory for agent socket */
+    strlcpy(socket_dir, "/tmp/ssh-XXXXXXXXXX", sizeof socket_dir);
+    if (mkdtemp(socket_dir) == NULL) {
+        perror("mkdtemp: private socket dir");
+        exit(1);
+    }
+
+    if (atexit(remove_socket_dir)) {
+        fprintf(stderr, "Can't install atexit handler to delete socket '%s'. "
+                        "Do it yourself!\n", socket_name);
+        exit(1);
+    }
+
+    int ret = snprintf(socket_name, sizeof(socket_name), 
+                       "%s/agent.%ld", socket_dir, (long)getpid());
+    if (ret >= sizeof(socket_name)) {
+        // Would have liked to print more...
+        fprintf(stderr, "socket_name too long (%d >= %d).\n",
+                ret, sizeof(socket_name));
+        exit(1);
+    }
+
+
+#if 0
     } else {
         /* Try to use specified agent socket */
         socket_dir[0] = '\0';
         strlcpy(socket_name, agentsocket, sizeof socket_name);
     }
+#endif
 
 
     sock = socket(AF_UNIX, SOCK_STREAM, 0);
@@ -41,17 +108,23 @@ create_socket(void)
     memset(&sunaddr, 0, sizeof(sunaddr));
     sunaddr.sun_family = AF_UNIX;
     strlcpy(sunaddr.sun_path, socket_name, sizeof(sunaddr.sun_path));
-    prev_mask = umask(0177);
+    int prev_mask = umask(0177);
     if (bind(sock, (struct sockaddr *) &sunaddr, sizeof(sunaddr)) < 0) {
         perror("bind");
-        *socket_name = '\0'; /* Don't unlink any existing file */
         umask(prev_mask);
-            cleanup_exit(1);
+        exit(1);
+    }
+
+    if (atexit(remove_socket)) {
+        fprintf(stderr, "Can't install atexit handler to delete socket '%s'. "
+                        "Do it yourself!\n", socket_name);
+        exit(1);
     }
+
     umask(prev_mask);
-    if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
+    if (listen(sock, LISTEN_BACKLOG) < 0) {
         perror("listen");
-        cleanup_exit(1);
+        exit(1);
     }
 }
 
@@ -69,11 +142,35 @@ kill_old_agent(void)
 void
 fork_subprocess(void)
 {
+    int pid = fork();
+
+    if (-1 == pid) {
+        perror("fork");
+        exit(1);
+    }
+
+    if (pid) {  // Parent
+        printf("%s=%s; export %s\n", SSH_AUTHSOCKET_ENV_NAME, socket_name,
+                                   SSH_AUTHSOCKET_ENV_NAME);
+        printf("%s=%ld; export %s\n", SSH_AGENTPID_ENV_NAME, (long) pid,
+                                   SSH_AGENTPID_ENV_NAME);
+
+        // TODO: If argv present, fork and exec it. Only do above if no args.
+
+        remove_socket_at_exit = 0;
+        exit(0);
+    }
+
+    // Child
+    if (setsid() == -1) {
+        perror("setsid");
+    }
 }
 
 void
-go(void)
+handle_key_requests_forever(void)
 {
+    // Select on sockets, etc etc
 }
 
 int
@@ -82,20 +179,25 @@ main(int argc, char **argv)
     /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
     // TODO: sanitise_stdfd();
 
+#if 0
     parse_cmdline(argc, argv);
 
     if (g_kill_flag) {
         kill_old_agent();
         exit(0);
     }
+#endif
 
     create_socket();
 
+#if 0
     if (! g_debug_flag) {
-        fork_subprocess();
     }
+#endif
+
+    fork_subprocess();
 
-    go();
+    handle_key_requests_forever();
 
     /* NOTREACHED */
 
diff --git a/cmdline.c b/cmdline.c
index def80f0..d23b8f5 100644
--- a/cmdline.c
+++ b/cmdline.c
@@ -16,6 +16,9 @@ int g_kill_flag = 0;
 int g_debug_flag = 0;
 char *g_socket_name = 0;
 
+int g_subprocess_argc;
+char **g_subprocess_argv;
+
 static void
 usage(void)
 {