From af87d247df5ebe6b94e04624c35b59155ae99eb5 Mon Sep 17 00:00:00 2001

From: "Richard W.M. Jones" <rjones@redhat.com>

Date: Thu, 23 Jun 2016 14:25:23 +0100

Subject: [PATCH] p2v: ssh: Improve consistency of error messages.

(cherry picked from commit 8f8a651e591064d87974bd322a995519347ebae7)

---

 p2v/ssh.c | 133 +++++++++++++++++++++++++++++++++++---------------------------

 1 file changed, 75 insertions(+), 58 deletions(-)

diff --git a/p2v/ssh.c b/p2v/ssh.c

index 083e04e..93c4c55 100644

--- a/p2v/ssh.c

+++ b/p2v/ssh.c

@@ -93,6 +93,21 @@ get_ssh_error (void)

   return ssh_error;

 }

+/* Like set_ssh_error, but for errors that aren't supposed to happen. */

+#define set_ssh_internal_error(fs, ...) \

+  set_ssh_error ("internal error: " fs, ##__VA_ARGS__)

+#define set_ssh_mexp_error(fn) \

+  set_ssh_internal_error ("%s: %m", fn)

+#define set_ssh_pcre_error() \

+  set_ssh_internal_error ("pcre error: %d\n", mexp_get_pcre_error (h))

+

+#define set_ssh_unexpected_eof(fs, ...)                               \

+  set_ssh_error ("remote server closed the connection unexpectedly, " \

+                 "waiting for: " fs, ##__VA_ARGS__)

+#define set_ssh_unexpected_timeout(fs, ...)               \

+  set_ssh_error ("remote server timed out unexpectedly, " \

+                 "waiting for: " fs, ##__VA_ARGS__)

+

 static void compile_regexps (void) __attribute__((constructor));

 static void free_regexps (void) __attribute__((destructor));

@@ -241,7 +256,7 @@ curl_download (const char *url, const char *local_file)

     return -1;

   }

   else if (!WIFEXITED (r)) {

-    set_ssh_error ("curl subprocess got a signal (%d)", r);

+    set_ssh_internal_error ("curl subprocess got a signal (%d)", r);

     unlink (error_file);

     return -1;

   }

@@ -353,7 +368,7 @@ start_ssh (struct config *config, char **extra_args, int wait_prompt)

   h = mexp_spawnv ("ssh", (char **) args);

   if (h == NULL) {

-    set_ssh_error ("internal error: ssh: mexp_spawnv: %m");

+    set_ssh_internal_error ("ssh: mexp_spawnv: %m");

     return NULL;

   }

@@ -371,7 +386,7 @@ start_ssh (struct config *config, char **extra_args, int wait_prompt)

                          }, ovector, ovecsize)) {

     case 100:                   /* Got password prompt. */

       if (mexp_printf (h, "%s\n", config->password) == -1) {

-        set_ssh_error ("mexp_printf: %m");

+        set_ssh_mexp_error ("mexp_printf");

         mexp_close (h);

         return NULL;

       }

@@ -383,7 +398,6 @@ start_ssh (struct config *config, char **extra_args, int wait_prompt)

       goto wait_password_again;

     case MEXP_EOF:

-      mexp_close (h);

       /* This is where we get to if the user enters an incorrect or

        * impossible hostname or port number.  Hopefully ssh printed an

        * error message, and we picked it up and put it in

@@ -393,21 +407,22 @@ start_ssh (struct config *config, char **extra_args, int wait_prompt)

       if (ssh_message)

         set_ssh_error ("%s", ssh_message);

       else

-        set_ssh_error ("unknown ssh error");

+        set_ssh_error ("ssh closed the connection without printing an error.");

+      mexp_close (h);

       return NULL;

     case MEXP_TIMEOUT:

+      set_ssh_unexpected_timeout ("password prompt");

       mexp_close (h);

-      set_ssh_error ("timeout waiting for password prompt");

       return NULL;

     case MEXP_ERROR:

-      set_ssh_error ("mexp_expect: %m");

+      set_ssh_mexp_error ("mexp_expect");

       mexp_close (h);

       return NULL;

     case MEXP_PCRE_ERROR:

-      set_ssh_error ("PCRE error: %d\n", mexp_get_pcre_error (h));

+      set_ssh_pcre_error ();

       mexp_close (h);

       return NULL;

     }

@@ -435,7 +450,7 @@ start_ssh (struct config *config, char **extra_args, int wait_prompt)

    * (https://bugzilla.redhat.com/1314244#c9).

    */

   if (mexp_printf (h, "exec bash --noediting --noprofile\n") == -1) {

-    set_ssh_error ("setting bash as remote shell: %m");

+    set_ssh_mexp_error ("mexp_printf");

     mexp_close (h);

     return NULL;

   }

@@ -449,7 +464,7 @@ start_ssh (struct config *config, char **extra_args, int wait_prompt)

     int r;

     if (guestfs_int_random_string (magic, 8) == -1) {

-      set_ssh_error ("random_string: %m");

+      set_ssh_internal_error ("random_string: %m");

       mexp_close (h);

       return NULL;

     }

@@ -458,7 +473,7 @@ start_ssh (struct config *config, char **extra_args, int wait_prompt)

      * mistake the command echo for the prompt.

      */

     if (mexp_printf (h, "export LANG=C PS1='###''%s''### '\n", magic) == -1) {

-      set_ssh_error ("random_string: %m");

+      set_ssh_mexp_error ("mexp_printf");

       mexp_close (h);

       return NULL;

     }

@@ -472,8 +487,8 @@ start_ssh (struct config *config, char **extra_args, int wait_prompt)

                            { 0 }

                          }, ovector, ovecsize)) {

     case 100:                    /* Got password prompt unexpectedly. */

+      set_ssh_error ("Login failed.  Probably the username and/or password is wrong.");

       mexp_close (h);

-      set_ssh_error ("login failed - probably the username and/or password is wrong");

       return NULL;

     case 101:

@@ -483,7 +498,7 @@ start_ssh (struct config *config, char **extra_args, int wait_prompt)

       r = pcre_get_substring (h->buffer, ovector,

                               mexp_get_pcre_error (h), 1, &matched);

       if (r < 0) {

-        fprintf (stderr, "error: PCRE error reading substring (%d)\n", r);

+        fprintf (stderr, "error: pcre error reading substring (%d)\n", r);

         exit (EXIT_FAILURE);

       }

       r = STREQ (magic, matched);

@@ -493,8 +508,8 @@ start_ssh (struct config *config, char **extra_args, int wait_prompt)

       goto got_prompt;

     case MEXP_EOF:

+      set_ssh_unexpected_eof ("the command prompt");

       mexp_close (h);

-      set_ssh_error ("unexpected end of file waiting for command prompt");

       return NULL;

     case MEXP_TIMEOUT:

@@ -504,19 +519,19 @@ start_ssh (struct config *config, char **extra_args, int wait_prompt)

       break;

     case MEXP_ERROR:

-      set_ssh_error ("mexp_expect: %m");

+      set_ssh_mexp_error ("mexp_expect");

       mexp_close (h);

       return NULL;

     case MEXP_PCRE_ERROR:

-      set_ssh_error ("PCRE error: %d\n", mexp_get_pcre_error (h));

+      set_ssh_pcre_error ();

       mexp_close (h);

       return NULL;

     }

   }

+  set_ssh_error ("Failed to synchronize with remote shell after 60 seconds.");

   mexp_close (h);

-  set_ssh_error ("failed to synchronize with remote shell after 60 seconds");

   return NULL;

  got_prompt:

@@ -556,7 +571,7 @@ test_connection (struct config *config)

   if (mexp_printf (h,

                    "%svirt-v2v --version\n",

                    config->sudo ? "sudo -n " : "") == -1) {

-    set_ssh_error ("mexp_printf: %m");

+    set_ssh_mexp_error ("mexp_printf");

     mexp_close (h);

     return -1;

   }

@@ -582,28 +597,28 @@ test_connection (struct config *config)

       goto end_of_version;

     case 102:

-      mexp_close (h);

       set_ssh_error ("sudo for user \"%s\" requires a password.  Edit /etc/sudoers on the conversion server to ensure the \"NOPASSWD:\" option is set for this user.",

                      config->username);

+      mexp_close (h);

       return -1;

     case MEXP_EOF:

+      set_ssh_unexpected_eof ("\"virt-v2v --version\" output");

       mexp_close (h);

-      set_ssh_error ("unexpected end of file waiting virt-v2v --version output");

       return -1;

     case MEXP_TIMEOUT:

+      set_ssh_unexpected_timeout ("\"virt-v2v --version\" output");

       mexp_close (h);

-      set_ssh_error ("timeout waiting for virt-v2v --version output");

       return -1;

     case MEXP_ERROR:

-      set_ssh_error ("mexp_expect: %m");

+      set_ssh_mexp_error ("mexp_expect");

       mexp_close (h);

       return -1;

     case MEXP_PCRE_ERROR:

-      set_ssh_error ("PCRE error: %d\n", mexp_get_pcre_error (h));

+      set_ssh_pcre_error ();

       mexp_close (h);

       return -1;

     }

@@ -612,9 +627,9 @@ test_connection (struct config *config)

   /* Got the prompt but no version number. */

   if (v2v_version == NULL) {

-    mexp_close (h);

     set_ssh_error ("virt-v2v is not installed on the conversion server, "

-                   "or it might be a too old version");

+                   "or it might be a too old version.");

+    mexp_close (h);

     return -1;

   }

@@ -634,7 +649,7 @@ test_connection (struct config *config)

   /* Get virt-v2v features.  See: v2v/cmdline.ml */

   if (mexp_printf (h, "%svirt-v2v --machine-readable\n",

                    config->sudo ? "sudo -n " : "") == -1) {

-    set_ssh_error ("mexp_printf: %m");

+    set_ssh_mexp_error ("mexp_printf");

     mexp_close (h);

     return -1;

   }

@@ -677,22 +692,22 @@ test_connection (struct config *config)

       goto end_of_machine_readable;

     case MEXP_EOF:

+      set_ssh_unexpected_eof ("\"virt-v2v --machine-readable\" output");

       mexp_close (h);

-      set_ssh_error ("unexpected end of file waiting virt-v2v --machine-readable output");

       return -1;

     case MEXP_TIMEOUT:

+      set_ssh_unexpected_timeout ("\"virt-v2v --machine-readable\" output");

       mexp_close (h);

-      set_ssh_error ("timeout waiting virt-v2v --machine-readable output");

       return -1;

     case MEXP_ERROR:

-      set_ssh_error ("mexp_expect: %m");

+      set_ssh_mexp_error ("mexp_expect");

       mexp_close (h);

       return -1;

     case MEXP_PCRE_ERROR:

-      set_ssh_error ("PCRE error: %d\n", mexp_get_pcre_error (h));

+      set_ssh_pcre_error ();

       mexp_close (h);

       return -1;

     }

@@ -700,14 +715,14 @@ test_connection (struct config *config)

  end_of_machine_readable:

   if (!feature_libguestfs_rewrite) {

+    set_ssh_error ("Invalid output of \"virt-v2v --machine-readable\" command.");

     mexp_close (h);

-    set_ssh_error ("invalid output of virt-v2v --machine-readable command");

     return -1;

   }

   /* Test finished, shut down ssh. */

   if (mexp_printf (h, "exit\n") == -1) {

-    set_ssh_error ("mexp_printf: %m");

+    set_ssh_mexp_error ("mexp_printf");

     mexp_close (h);

     return -1;

   }

@@ -717,30 +732,31 @@ test_connection (struct config *config)

     break;

   case MEXP_TIMEOUT:

+    set_ssh_unexpected_timeout ("end of ssh session");

     mexp_close (h);

-    set_ssh_error ("timeout waiting for end of ssh session");

     return -1;

   case MEXP_ERROR:

-    set_ssh_error ("mexp_expect: %m");

+    set_ssh_mexp_error ("mexp_expect");

     mexp_close (h);

     return -1;

   case MEXP_PCRE_ERROR:

-    set_ssh_error ("PCRE error: %d\n", mexp_get_pcre_error (h));

+    set_ssh_pcre_error ();

     mexp_close (h);

     return -1;

   }

   status = mexp_close (h);

   if (status == -1) {

-    set_ssh_error ("mexp_close: %m");

+    set_ssh_internal_error ("mexp_close: %m");

     return -1;

   }

   if (WIFSIGNALED (status) && WTERMSIG (status) == SIGHUP)

     return 0; /* not an error */

   if (!WIFEXITED (status) || WEXITSTATUS (status) != 0) {

-    set_ssh_error ("unexpected close status from ssh subprocess (%d)", status);

+    set_ssh_internal_error ("unexpected close status from ssh subprocess (%d)",

+                            status);

     return -1;

   }

   return 0;

@@ -799,7 +815,7 @@ compatible_version (const char *v2v_version)

   /* The major version must always be 1. */

   if (!STRPREFIX (v2v_version, "1.")) {

     set_ssh_error ("virt-v2v major version is not 1 (\"%s\"), "

-                   "this version of virt-p2v is not compatible",

+                   "this version of virt-p2v is not compatible.",

                    v2v_version);

     return 0;

   }

@@ -810,15 +826,15 @@ compatible_version (const char *v2v_version)

    * We should remain compatible with any virt-v2v after 1.28.

    */

   if (sscanf (v2v_version, "1.%u", &v2v_minor) != 1) {

-    set_ssh_error ("cannot parse virt-v2v version string (\"%s\")",

-                   v2v_version);

+    set_ssh_internal_error ("cannot parse virt-v2v version string (\"%s\")",

+                            v2v_version);

     return 0;

   }

   if (v2v_minor < 28) {

     set_ssh_error ("virt-v2v version is < 1.28 (\"%s\"), "

                    "you must upgrade to virt-v2v >= 1.28 on "

-                   "the conversion server", v2v_version);

+                   "the conversion server.", v2v_version);

     return 0;

   }

@@ -858,34 +874,35 @@ open_data_connection (struct config *config, int *local_port, int *remote_port)

   case 100:                     /* Ephemeral port. */

     port_str = strndup (&h->buffer[ovector[2]], ovector[3]-ovector[2]);

     if (port_str == NULL) {

-      set_ssh_error ("not enough memory for strndup");

+      set_ssh_internal_error ("strndup: %m");

       mexp_close (h);

       return NULL;

     }

     if (sscanf (port_str, "%d", remote_port) != 1) {

-      set_ssh_error ("cannot extract the port number from '%s'", port_str);

+      set_ssh_internal_error ("cannot extract the port number from '%s'",

+                              port_str);

       mexp_close (h);

       return NULL;

     }

     break;

   case MEXP_EOF:

+    set_ssh_unexpected_eof ("\"ssh -R\" output");

     mexp_close (h);

-    set_ssh_error ("unexpected end of file waiting ssh -R output");

     return NULL;

   case MEXP_TIMEOUT:

+    set_ssh_unexpected_timeout ("\"ssh -R\" output");

     mexp_close (h);

-    set_ssh_error ("timeout waiting for ssh -R output");

     return NULL;

   case MEXP_ERROR:

-    set_ssh_error ("mexp_expect: %m");

+    set_ssh_mexp_error ("mexp_expect");

     mexp_close (h);

     return NULL;

   case MEXP_PCRE_ERROR:

-    set_ssh_error ("PCRE error: %d\n", mexp_get_pcre_error (h));

+    set_ssh_pcre_error ();

     mexp_close (h);

     return NULL;

   }

@@ -909,19 +926,19 @@ wait_for_prompt (mexp_h *h)

     return 0;

   case MEXP_EOF:

-    set_ssh_error ("unexpected end of file waiting for prompt");

+    set_ssh_unexpected_eof ("command prompt");

     return -1;

   case MEXP_TIMEOUT:

-    set_ssh_error ("timeout waiting for prompt");

+    set_ssh_unexpected_timeout ("command prompt");

     return -1;

   case MEXP_ERROR:

-    set_ssh_error ("mexp_expect: %m");

+    set_ssh_mexp_error ("mexp_expect");

     return -1;

   case MEXP_PCRE_ERROR:

-    set_ssh_error ("PCRE error: %d\n", mexp_get_pcre_error (h));

+    set_ssh_pcre_error ();

     return -1;

   }

@@ -947,7 +964,7 @@ start_remote_connection (struct config *config,

   /* Create the remote directory. */

   if (mexp_printf (h, "mkdir %s\n", remote_dir) == -1) {

-    set_ssh_error ("mexp_printf: %m");

+    set_ssh_mexp_error ("mexp_printf");

     goto error;

   }

@@ -957,7 +974,7 @@ start_remote_connection (struct config *config,

   /* Write some useful config information to files in the remote directory. */

   if (mexp_printf (h, "echo '%s' > %s/name\n",

                    config->guestname, remote_dir) == -1) {

-    set_ssh_error ("mexp_printf: %m");

+    set_ssh_mexp_error ("mexp_printf");

     goto error;

   }

@@ -965,7 +982,7 @@ start_remote_connection (struct config *config,

     goto error;

   if (mexp_printf (h, "date > %s/time\n", remote_dir) == -1) {

-    set_ssh_error ("mexp_printf: %m");

+    set_ssh_mexp_error ("mexp_printf");

     goto error;

   }

@@ -980,7 +997,7 @@ start_remote_connection (struct config *config,

                    remote_dir, magic,

                    libvirt_xml,

                    magic) == -1) {

-    set_ssh_error ("mexp_printf: %m");

+    set_ssh_mexp_error ("mexp_printf");

     goto error;

   }

@@ -995,7 +1012,7 @@ start_remote_connection (struct config *config,

                    remote_dir, magic,

                    wrapper_script,

                    magic) == -1) {

-    set_ssh_error ("mexp_printf: %m");

+    set_ssh_mexp_error ("mexp_printf");

     goto error;

   }

@@ -1003,7 +1020,7 @@ start_remote_connection (struct config *config,

     goto error;

   if (mexp_printf (h, "chmod +x %s/virt-v2v-wrapper.sh\n", remote_dir) == -1) {

-    set_ssh_error ("mexp_printf: %m");

+    set_ssh_mexp_error ("mexp_printf");

     goto error;

   }

@@ -1020,7 +1037,7 @@ start_remote_connection (struct config *config,

                      remote_dir, magic,

                      dmesg,

                      magic) == -1) {

-      set_ssh_error ("mexp_printf: %m");

+      set_ssh_mexp_error ("mexp_printf");

       goto error;

     }

-- 

2.7.4