From dfa319bc27420a611311834108e6807b300fc2b3 Mon Sep 17 00:00:00 2001

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

Date: Tue, 9 Jun 2015 17:53:05 +0100

Subject: [PATCH] p2v: Correct parsing of /proc/cmdline, including quoting.

Fix the parsing of /proc/cmdline, including allowing double quoting of

parameters.

This allows you to pass parameters to p2v on the command line which

include spaces.

(cherry picked from commit 716244c33718c866edce9e7ee8f21ee612f53337)

---

 p2v/Makefile.am      |   1 +

 p2v/kernel-cmdline.c | 193 +++++++++++++++++++++++++++++++++++++++++++++++++++

 p2v/kernel.c         | 143 ++++++++++++++++----------------------

 p2v/main.c           |  55 ++++-----------

 p2v/p2v.h            |  10 ++-

 po/POTFILES          |   1 +

 6 files changed, 277 insertions(+), 126 deletions(-)

 create mode 100644 p2v/kernel-cmdline.c

diff --git a/p2v/Makefile.am b/p2v/Makefile.am

index c9d6b6f..cafe597 100644

--- a/p2v/Makefile.am

+++ b/p2v/Makefile.am

@@ -49,6 +49,7 @@ virt_p2v_SOURCES = \

 	copying.c \

 	gui.c \

 	kernel.c \

+	kernel-cmdline.c \

 	main.c \

 	miniexpect.c \

 	miniexpect.h \

diff --git a/p2v/kernel-cmdline.c b/p2v/kernel-cmdline.c

new file mode 100644

index 0000000..142108a

--- /dev/null

+++ b/p2v/kernel-cmdline.c

@@ -0,0 +1,193 @@

+/* virt-p2v

+ * Copyright (C) 2015 Red Hat Inc.

+ *

+ * This program is free software; you can redistribute it and/or modify

+ * it under the terms of the GNU General Public License as published by

+ * the Free Software Foundation; either version 2 of the License, or

+ * (at your option) any later version.

+ *

+ * This program is distributed in the hope that it will be useful,

+ * but WITHOUT ANY WARRANTY; without even the implied warranty of

+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

+ * GNU General Public License for more details.

+ *

+ * You should have received a copy of the GNU General Public License

+ * along with this program; if not, write to the Free Software

+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

+ */

+

+/* Read /proc/cmdline.

+ *

+ * We only support double quoting, consistent with the Linux

+ * documentation.

+ * https://www.kernel.org/doc/Documentation/kernel-parameters.txt

+ *

+ * systemd supports single and double quoting and single character

+ * escaping, but we don't support all that.

+ *

+ * Returns a list of key, value pairs, terminated by NULL.

+ */

+

+#include <config.h>

+

+#include <stdio.h>

+#include <stdlib.h>

+#include <string.h>

+#include <unistd.h>

+#include <errno.h>

+

+#include "p2v.h"

+

+static void

+add_null (char ***argv, size_t *lenp)

+{

+  (*lenp)++;

+  *argv = realloc (*argv, *lenp * sizeof (char *));

+  if (*argv == NULL) {

+    perror ("realloc");

+    exit (EXIT_FAILURE);

+  }

+  (*argv)[(*lenp)-1] = NULL;

+}

+

+static void

+add_string (char ***argv, size_t *lenp, const char *str, size_t len)

+{

+  add_null (argv, lenp);

+  (*argv)[(*lenp)-1] = strndup (str, len);

+  if ((*argv)[(*lenp)-1] == NULL) {

+    perror ("strndup");

+    exit (EXIT_FAILURE);

+  }

+}

+

+char **

+parse_cmdline_string (const char *cmdline)

+{

+  char **ret = NULL;

+  size_t len = 0;

+  const char *p, *key = NULL, *value = NULL;

+  enum {

+    KEY_START = 0,

+    KEY,

+    VALUE_START,

+    VALUE,

+    VALUE_QUOTED

+  } state = 0;

+

+  for (p = cmdline; *p; p++) {

+    switch (state) {

+    case KEY_START:             /* looking for the start of a key */

+      if (*p == ' ') continue;

+      key = p;

+      state = KEY;

+      break;

+

+    case KEY:                   /* reading key */

+      if (*p == ' ') {

+        add_string (&ret, &len, key, p-key);

+        add_string (&ret, &len, "", 0);

+        state = KEY_START;

+      }

+      else if (*p == '=') {

+        add_string (&ret, &len, key, p-key);

+        state = VALUE_START;

+      }

+      break;

+

+    case VALUE_START:           /* looking for the start of a value */

+      if (*p == ' ') {

+        add_string (&ret, &len, "", 0);

+        state = KEY_START;

+      }

+      else if (*p == '"') {

+        value = p+1;

+        state = VALUE_QUOTED;

+      }

+      else {

+        value = p;

+        state = VALUE;

+      }

+      break;

+

+    case VALUE:                 /* reading unquoted value */

+      if (*p == ' ') {

+        add_string (&ret, &len, value, p-value);

+        state = KEY_START;

+      }

+      break;

+

+    case VALUE_QUOTED:          /* reading quoted value */

+      if (*p == '"') {

+        add_string (&ret, &len, value, p-value);

+        state = KEY_START;

+      }

+      break;

+    }

+  }

+

+  switch (state) {

+  case KEY_START: break;

+  case KEY:                     /* key followed by end of string */

+    add_string (&ret, &len, key, p-key);

+    add_string (&ret, &len, "", 0);

+    break;

+  case VALUE_START:             /* key= followed by end of string */

+    add_string (&ret, &len, "", 0);

+    break;

+  case VALUE:                   /* key=value followed by end of string */

+    add_string (&ret, &len, value, p-value);

+    break;

+  case VALUE_QUOTED:            /* unterminated key="value" */

+    fprintf (stderr, "%s: warning: unterminated quoted string on kernel command line\n",

+             guestfs_int_program_name);

+    add_string (&ret, &len, value, p-value);

+  }

+

+  add_null (&ret, &len;;

+

+  return ret;

+}

+

+char **

+parse_proc_cmdline (void)

+{

+  CLEANUP_FCLOSE FILE *fp = NULL;

+  CLEANUP_FREE char *cmdline = NULL;

+  size_t len = 0;

+

+  fp = fopen ("/proc/cmdline", "re");

+  if (fp == NULL) {

+    perror ("/proc/cmdline");

+    return NULL;

+  }

+

+  if (getline (&cmdline, &len, fp) == -1) {

+    perror ("getline");

+    return NULL;

+  }

+

+  /* 'len' is not the length of the string, but the length of the

+   * buffer.  We need to chomp the string.

+   */

+  len = strlen (cmdline);

+

+  if (len >= 1 && cmdline[len-1] == '\n')

+    cmdline[len-1] = '\0';

+

+  return parse_cmdline_string (cmdline);

+}

+

+const char *

+get_cmdline_key (char **argv, const char *key)

+{

+  size_t i;

+

+  for (i = 0; argv[i] != NULL; i += 2) {

+    if (STREQ (argv[i], key))

+      return argv[i+1];

+  }

+

+  /* Not found. */

+  return NULL;

+}

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

index 481ac78..88d18bd 100644

--- a/p2v/kernel.c

+++ b/p2v/kernel.c

@@ -35,46 +35,38 @@

 static void notify_ui_callback (int type, const char *data);

 void

-kernel_configuration (struct config *config, const char *cmdline)

+kernel_configuration (struct config *config, char **cmdline, int cmdline_source)

 {

-  const char *r;

-  size_t len;

+  const char *p;

-  r = strstr (cmdline, "p2v.server=");

-  assert (r); /* checked by caller */

-  r += 5+6;

-  len = strcspn (r, " ");

+  p = get_cmdline_key (cmdline, "p2v.server");

+  assert (p); /* checked by caller */

   free (config->server);

-  config->server = strndup (r, len);

+  config->server = strdup (p);

-  r = strstr (cmdline, "p2v.port=");

-  if (r) {

-    r += 5+4;

-    if (sscanf (r, "%d", &config->port) != 1) {

+  p = get_cmdline_key (cmdline, "p2v.port");

+  if (p) {

+    if (sscanf (p, "%d", &config->port) != 1) {

       fprintf (stderr, "%s: cannot parse p2v.port from kernel command line",

                guestfs_int_program_name);

       exit (EXIT_FAILURE);

     }

   }

-  r = strstr (cmdline, "p2v.username=");

-  if (r) {

-    r += 5+8;

-    len = strcspn (r, " ");

+  p = get_cmdline_key (cmdline, "p2v.username");

+  if (p) {

     free (config->username);

-    config->username = strndup (r, len);

+    config->username = strdup (p);

   }

-  r = strstr (cmdline, "p2v.password=");

-  if (r) {

-    r += 5+8;

-    len = strcspn (r, " ");

+  p = get_cmdline_key (cmdline, "p2v.password");

+  if (p) {

     free (config->password);

-    config->password = strndup (r, len);

+    config->password = strdup (p);

   }

-  r = strstr (cmdline, "p2v.sudo");

-  if (r)

+  p = get_cmdline_key (cmdline, "p2v.sudo");

+  if (p)

     config->sudo = 1;

   /* We should now be able to connect and interrogate virt-v2v

@@ -88,30 +80,26 @@ kernel_configuration (struct config *config, const char *cmdline)

     exit (EXIT_FAILURE);

   }

-  r = strstr (cmdline, "p2v.name=");

-  if (r) {

-    r += 5+4;

-    len = strcspn (r, " ");

+  p = get_cmdline_key (cmdline, "p2v.name");

+  if (p) {

     free (config->guestname);

-    config->guestname = strndup (r, len);

+    config->guestname = strdup (p);

   }

-  r = strstr (cmdline, "p2v.vcpus=");

-  if (r) {

-    r += 5+5;

-    if (sscanf (r, "%d", &config->vcpus) != 1) {

+  p = get_cmdline_key (cmdline, "p2v.vcpus");

+  if (p) {

+    if (sscanf (p, "%d", &config->vcpus) != 1) {

       fprintf (stderr, "%s: cannot parse p2v.vcpus from kernel command line\n",

                guestfs_int_program_name);

       exit (EXIT_FAILURE);

     }

   }

-  r = strstr (cmdline, "p2v.memory=");

-  if (r) {

+  p = get_cmdline_key (cmdline, "p2v.memory");

+  if (p) {

     char mem_code[2];

-    r += 5+6;

-    if (sscanf (r, "%" SCNu64 "%c", &config->memory, mem_code) != 1) {

+    if (sscanf (p, "%" SCNu64 "%c", &config->memory, mem_code) != 1) {

       fprintf (stderr, "%s: cannot parse p2v.memory from kernel command line\n",

                guestfs_int_program_name);

       exit (EXIT_FAILURE);

@@ -128,88 +116,75 @@ kernel_configuration (struct config *config, const char *cmdline)

     }

   }

-  r = strstr (cmdline, "p2v.disks=");

-  if (r) {

+  p = get_cmdline_key (cmdline, "p2v.disks");

+  if (p) {

     CLEANUP_FREE char *t;

-    r += 5+5;

-    len = strcspn (r, " ");

-    t = strndup (r, len);

+    t = strdup (p);

     guestfs_int_free_string_list (config->disks);

     config->disks = guestfs_int_split_string (',', t);

   }

-  r = strstr (cmdline, "p2v.removable=");

-  if (r) {

+  p = get_cmdline_key (cmdline, "p2v.removable");

+  if (p) {

     CLEANUP_FREE char *t;

-    r += 5+9;

-    len = strcspn (r, " ");

-    t = strndup (r, len);

+    t = strdup (p);

     guestfs_int_free_string_list (config->removable);

     config->removable = guestfs_int_split_string (',', t);

   }

-  r = strstr (cmdline, "p2v.interfaces=");

-  if (r) {

+  p = get_cmdline_key (cmdline, "p2v.interfaces");

+  if (p) {

     CLEANUP_FREE char *t;

-    r += 5+10;

-    len = strcspn (r, " ");

-    t = strndup (r, len);

+    t = strdup (p);

     guestfs_int_free_string_list (config->interfaces);

     config->interfaces = guestfs_int_split_string (',', t);

   }

-  r = strstr (cmdline, "p2v.network=");

-  if (r) {

+  p = get_cmdline_key (cmdline, "p2v.network");

+  if (p) {

     CLEANUP_FREE char *t;

-    r += 5+7;

-    len = strcspn (r, " ");

-    t = strndup (r, len);

+    t = strdup (p);

     guestfs_int_free_string_list (config->network_map);

     config->network_map = guestfs_int_split_string (',', t);

   }

-  r = strstr (cmdline, "p2v.o=");

-  if (r) {

-    r += 5+1;

-    len = strcspn (r, " ");

+  p = get_cmdline_key (cmdline, "p2v.o");

+  if (p) {

     free (config->output);

-    config->output = strndup (r, len);

+    config->output = strdup (p);

   }

-  r = strstr (cmdline, "p2v.oa=sparse");

-  if (r)

-    config->output_allocation = OUTPUT_ALLOCATION_SPARSE;

-

-  r = strstr (cmdline, "p2v.oa=preallocated");

-  if (r)

-    config->output_allocation = OUTPUT_ALLOCATION_PREALLOCATED;

+  p = get_cmdline_key (cmdline, "p2v.oa");

+  if (p) {

+    if (STREQ (p, "sparse"))

+      config->output_allocation = OUTPUT_ALLOCATION_SPARSE;

+    else if (STREQ (p, "preallocated"))

+      config->output_allocation = OUTPUT_ALLOCATION_PREALLOCATED;

+    else

+      fprintf (stderr, "%s: warning: don't know what p2v.oa=%s means\n",

+               guestfs_int_program_name, p);

+  }

-  r = strstr (cmdline, "p2v.oc=");

-  if (r) {

-    r += 5+2;

-    len = strcspn (r, " ");

+  p = get_cmdline_key (cmdline, "p2v.oc");

+  if (p) {

     free (config->output_connection);

-    config->output_connection = strndup (r, len);

+    config->output_connection = strdup (p);

   }

-  r = strstr (cmdline, "p2v.of=");

-  if (r) {

-    r += 5+2;

-    len = strcspn (r, " ");

+  p = get_cmdline_key (cmdline, "p2v.of");

+  if (p) {

     free (config->output_format);

-    config->output_format = strndup (r, len);

+    config->output_format = strdup (p);

   }

-  r = strstr (cmdline, "p2v.os=");

-  if (r) {

-    r += 5+2;

-    len = strcspn (r, " ");

+  p = get_cmdline_key (cmdline, "p2v.os");

+  if (p) {

     free (config->output_storage);

-    config->output_storage = strndup (r, len);

+    config->output_storage = strdup (p);

   }

   /* Perform the conversion in text mode. */

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

index 2dba1b8..4e67992 100644

--- a/p2v/main.c

+++ b/p2v/main.c

@@ -44,7 +44,6 @@ char **all_interfaces;

 static void set_config_defaults (struct config *config);

 static void find_all_disks (void);

 static void find_all_interfaces (void);

-static char *read_cmdline (void);

 static int cpuinfo_flags (void);

 enum { HELP_OPTION = CHAR_MAX + 1 };

@@ -99,7 +98,8 @@ main (int argc, char *argv[])

   gboolean gui_possible;

   int c;

   int option_index;

-  char *cmdline = NULL;

+  char **cmdline = NULL;

+  int cmdline_source = 0;

   struct config *config = new_config ();

   setlocale (LC_ALL, "");

@@ -120,7 +120,8 @@ main (int argc, char *argv[])

         display_long_options (long_options);

       }

       else if (STREQ (long_options[option_index].name, "cmdline")) {

-        cmdline = strdup (optarg);

+        cmdline = parse_cmdline_string (optarg);

+        cmdline_source = CMDLINE_SOURCE_COMMAND_LINE;

       }

       else {

         fprintf (stderr, _("%s: unknown long option: %s (%d)\n"),

@@ -158,16 +159,18 @@ main (int argc, char *argv[])

    * If /proc/cmdline contains p2v.debug then we enable verbose mode

    * even for interactive configuration.

    */

-  if (cmdline == NULL)

-    cmdline = read_cmdline ();

-  if (cmdline == NULL)

-    goto gui;

+  if (cmdline == NULL) {

+    cmdline = parse_proc_cmdline ();

+    if (cmdline == NULL)

+      goto gui;

+    cmdline_source = CMDLINE_SOURCE_PROC_CMDLINE;

+  }

-  if (strstr (cmdline, "p2v.debug"))

+  if (get_cmdline_key (cmdline, "p2v.debug") != NULL)

     config->verbose = 1;

-  if (strstr (cmdline, "p2v.server="))

-    kernel_configuration (config, cmdline);

+  if (get_cmdline_key (cmdline, "p2v.server") != NULL)

+    kernel_configuration (config, cmdline, cmdline_source);

   else {

   gui:

     if (!gui_possible)

@@ -176,7 +179,7 @@ main (int argc, char *argv[])

     gui_application (config);

   }

-  free (cmdline);

+  guestfs_int_free_string_list (cmdline);

   exit (EXIT_SUCCESS);

 }

@@ -498,36 +501,6 @@ find_all_interfaces (void)

     qsort (all_interfaces, nr_interfaces, sizeof (char *), compare);

 }

-/* Read /proc/cmdline. */

-static char *

-read_cmdline (void)

-{

-  CLEANUP_FCLOSE FILE *fp = NULL;

-  char *ret = NULL;

-  size_t len;

-

-  fp = fopen ("/proc/cmdline", "re");

-  if (fp == NULL) {

-    perror ("/proc/cmdline");

-    return NULL;

-  }

-

-  if (getline (&ret, &len, fp) == -1) {

-    perror ("getline");

-    return NULL;

-  }

-

-  /* 'len' is not the length of the string, but the length of the

-   * buffer.  We need to chomp the string.

-   */

-  len = strlen (ret);

-

-  if (len >= 1 && ret[len-1] == '\n')

-    ret[len-1] = '\0';

-

-  return ret;

-}

-

 /* Read the list of flags from /proc/cpuinfo. */

 static int

 cpuinfo_flags (void)

diff --git a/p2v/p2v.h b/p2v/p2v.h

index c5427a7..41d305d 100644

--- a/p2v/p2v.h

+++ b/p2v/p2v.h

@@ -85,8 +85,16 @@ extern struct config *new_config (void);

 extern struct config *copy_config (struct config *);

 extern void free_config (struct config *);

+/* kernel-cmdline.c */

+extern char **parse_cmdline_string (const char *cmdline);

+extern char **parse_proc_cmdline (void);

+extern const char *get_cmdline_key (char **cmdline, const char *key);

+

+#define CMDLINE_SOURCE_COMMAND_LINE 1 /* --cmdline */

+#define CMDLINE_SOURCE_PROC_CMDLINE 2 /* /proc/cmdline */

+

 /* kernel.c */

-extern void kernel_configuration (struct config *, const char *cmdline);

+extern void kernel_configuration (struct config *, char **cmdline, int cmdline_source);

 /* gui.c */

 extern void gui_application (struct config *);

diff --git a/po/POTFILES b/po/POTFILES

index 320710f..7c99fd0 100644

--- a/po/POTFILES

+++ b/po/POTFILES

@@ -258,6 +258,7 @@ p2v/config.c

 p2v/conversion.c

 p2v/copying.c

 p2v/gui.c

+p2v/kernel-cmdline.c

 p2v/kernel.c

 p2v/main.c

 p2v/miniexpect.c

-- 

1.8.3.1