Imported Upstream version 0.8.2 upstream/0.8.2

1 files changed, 368 insertions, 58 deletions

diff --git a/src/nm-policy-hosts.c b/src/nm-policy-hosts.c
index 7723c997..7f9cff80 100644
--- a/src/nm-policy-hosts.c
+++ b/src/nm-policy-hosts.c
@@ -18,15 +18,20 @@
  * Copyright (C) 2004 - 2010 Red Hat, Inc.
  */
 
+#include <config.h>
 #include <string.h>
 #include <unistd.h>
 #include <errno.h>
 #include <netdb.h>
 #include <ctype.h>
+#include <arpa/inet.h>
 
 #include "nm-policy-hosts.h"
 #include "nm-logging.h"
 
+#define IP4_LH "127.0.0.1"
+#define IP6_LH "::1"
+
 gboolean
 nm_policy_hosts_find_token (const char *line, const char *token)
 {
@@ -53,108 +58,385 @@ nm_policy_hosts_find_token (const char *line, const char *token)
 }
 
 static gboolean
-is_local_mapping (const char *str, const char *hostname)
+is_local_mapping (const char *str, gboolean ip6, const char *hostname)
+{
+	const char *addr = ip6 ? IP6_LH : IP4_LH;
+	const char *fallback = ip6 ? "localhost6" : "localhost";
+
+	return (   !strncmp (str, addr, strlen (addr))
+	        && nm_policy_hosts_find_token (str, hostname ? hostname : fallback));
+}
+
+static gboolean
+is_ip4_addr (const char *str)
+{
+	struct in_addr found;
+	char buf[INET_ADDRSTRLEN + 2];
+	const char *p = str;
+	guint32 i = 0;
+
+	memset (buf, 0, sizeof (buf));
+	while (*p && !isblank (*p) && (i < sizeof (buf)))
+		buf[i++] = *p++;
+
+	return inet_pton (AF_INET, buf, &found) == 1 ? TRUE : FALSE;
+}
+
+static gboolean
+ip4_addr_matches (const char *str, const char *ip4_addr)
+{
+	struct in_addr found, given;
+	char buf[INET_ADDRSTRLEN + 2];
+	const char *p = str;
+	guint32 i = 0;
+
+	g_return_val_if_fail (ip4_addr != NULL, FALSE);
+
+	memset (buf, 0, sizeof (buf));
+	while (*p && !isblank (*p) && (i < sizeof (buf)))
+		buf[i++] = *p++;
+
+	if (inet_pton (AF_INET, buf, &found) != 1)
+		return FALSE;
+	if (inet_pton (AF_INET, ip4_addr, &given) != 1)
+		return FALSE;
+
+	return memcmp (&found, &given, sizeof (found)) == 0;
+}
+
+static gboolean
+is_ip6_addr (const char *str)
+{
+	struct in6_addr found;
+	char buf[INET6_ADDRSTRLEN + 2];
+	const char *p = str;
+	guint32 i = 0;
+
+	memset (buf, 0, sizeof (buf));
+	while (*p && !isblank (*p) && (i < sizeof (buf)))
+		buf[i++] = *p++;
+
+	return inet_pton (AF_INET6, buf, &found) == 1 ? TRUE : FALSE;
+}
+
+static gboolean
+ip6_addr_matches (const char *str, const char *ip6_addr)
 {
-	return (   !strncmp (str, "127.0.0.1", strlen ("127.0.0.1"))
-	        && nm_policy_hosts_find_token (str, hostname ? hostname : "localhost"));
+	struct in6_addr found, given;
+	char buf[INET6_ADDRSTRLEN + 2];
+	const char *p = str;
+	guint32 i = 0;
+
+	g_return_val_if_fail (ip6_addr != NULL, FALSE);
+
+	memset (buf, 0, sizeof (buf));
+	while (*p && !isblank (*p) && (i < sizeof (buf)))
+		buf[i++] = *p++;
+
+	if (inet_pton (AF_INET6, buf, &found) != 1)
+		return FALSE;
+	if (inet_pton (AF_INET6, ip6_addr, &given) != 1)
+		return FALSE;
+
+	return memcmp (&found, &given, sizeof (found)) == 0;
 }
 
+static char *
+get_custom_hostnames (const char *line,
+                      const char *hostname,
+                      const char *old_hostname,
+                      const char *short_hostname,
+                      const char *fallback_hostname)
+{
+	char **items = NULL, **iter;
+	guint start = 0;
+	GString *str = NULL;
+	char *custom = NULL;
+
+	g_return_val_if_fail (line != NULL, NULL);
+
+	if (!strncmp (line, IP4_LH, strlen (IP4_LH)))
+		start = strlen (IP4_LH);
+	else if (!strncmp (line, IP6_LH, strlen (IP6_LH)))
+		start = strlen (IP6_LH);
+
+	g_return_val_if_fail (start > 0, NULL);
+
+	/* Split the line into tokens */
+	items = g_strsplit_set (line + start, " \t", -1);
+	if (!items)
+		return NULL;
+
+	str = g_string_sized_new (50);
+	/* Ignore current & old hostnames, and localhost-anything */
+	for (iter = items; iter && *iter; iter++) {
+		if (*iter[0] == '\0')
+			continue;
+		if (hostname && !strcmp (*iter, hostname))
+			continue;
+		if (old_hostname && !strcmp (*iter, old_hostname))
+			continue;
+		if (short_hostname && !strcmp (*iter, short_hostname))
+			continue;
+		if (fallback_hostname && !strcmp (*iter, fallback_hostname))
+			continue;
+		if (!strcmp (*iter, "localhost"))
+			continue;
+		if (!strcmp (*iter, "localhost6"))
+			continue;
+		if (!strcmp (*iter, "localhost.localdomain"))
+			continue;
+		if (!strcmp (*iter, "localhost4.localdomain4"))
+			continue;
+		if (!strcmp (*iter, "localhost6.localdomain6"))
+			continue;
+
+		/* Found a custom hostname */
+		g_string_append_c (str, '\t');
+		g_string_append (str, *iter);
+	}
+
+	if (str->len)
+		custom = g_string_free (str, FALSE);
+	else
+		g_string_free (str, TRUE);
+
+	g_strfreev (items);
+	return custom;
+}
+
+#define ADDED_TAG "# Added by NetworkManager"
+
 GString *
 nm_policy_get_etc_hosts (const char **lines,
                          gsize existing_len,
                          const char *hostname,
-                         const char *fallback_hostname,
+                         const char *old_hostname,
+                         const char *fallback_hostname4,
+                         const char *fallback_hostname6,
+                         const char *ip4_addr,
+                         const char *ip6_addr,
                          GError **error)
 {
 	GString *contents = NULL;
 	const char **line;
-	gboolean found_host_nonlocal = FALSE;
-	gboolean found_host = FALSE;
-	gboolean found_localhost = FALSE;
+	gboolean found_localhost4 = FALSE;
+	gboolean found_localhost6 = FALSE;
+	gboolean found_host4 = FALSE;
+	gboolean found_host6 = FALSE;
+	gboolean found_user_host4 = FALSE;
+	gboolean found_user_host6 = FALSE;
 	gboolean initial_comments = TRUE;
 	gboolean added = FALSE;
+	gboolean hostname4_is_fallback;
+	gboolean hostname6_is_fallback;
+	gboolean host4_before = FALSE;
+	gboolean host6_before = FALSE;
+	gboolean no_stale = TRUE;
+	char *short_hostname = NULL;
+	char *custom4 = NULL;
+	char *custom6 = NULL;
 
 	g_return_val_if_fail (lines != NULL, FALSE);
 	g_return_val_if_fail (hostname != NULL, FALSE);
 
-	/* /etc/hosts needs at least two things:
+	hostname4_is_fallback = !strcmp (hostname, fallback_hostname4);
+	hostname6_is_fallback = !strcmp (hostname, fallback_hostname6);
+
+	/* Find the short hostname, like 'foo' from 'foo.bar.baz'; we want to
+	 * make sure that the entries we add for this host also include the short
+	 * hostname too so that if the resolver does not answer queries for the
+	 * machine's actual hostname/domain, that stuff like 'ping foo' still works.
+	 */
+	if (!hostname4_is_fallback || !hostname6_is_fallback) {
+		char *dot;
+
+		short_hostname = g_strdup (hostname);
+		dot = strchr (short_hostname, '.');
+		if (dot && *(dot+1))
+			*dot = '\0';
+		else {
+			g_free (short_hostname);
+			short_hostname = NULL;
+		}
+	}
+
+	/* We need the following in /etc/hosts:
 	 *
-	 * 1) current hostname mapped to any address
-	 * 2) 'localhost' mapped to 127.0.0.1
+	 * 1) current hostname mapped to current IPv4 addresses if IPv4 is active
+	 * 2) current hostname mapped to current IPv6 addresses if IPv6 is active
+	 * 3) 'localhost' mapped to 127.0.0.1
+	 * 4) 'localhost6' mapped to ::1
 	 *
-	 * If both these conditions exist in /etc/hosts, we don't need to bother
-	 * updating the file.
+	 * If all these things exist we don't need to bother updating the file.
 	 */
 
-	/* Look for the two cases from above */
+	if (!ip4_addr)
+		host4_before = TRUE;
+	if (!ip6_addr)
+		host6_before = TRUE;
+
+	/* Look for the four cases from above */
 	for (line = lines; lines && *line; line++) {
-		if (strlen (*line) && (*line[0] != '#')) {
-			if (nm_policy_hosts_find_token (*line, hostname)) {
-				if (!is_local_mapping (*line, "localhost")) {
-					/* hostname is not on a 127.0.0.1 line or the line does not
-					 * contain 'localhost'.
-					 */
-					found_host_nonlocal = TRUE;
+		gboolean found_hostname = FALSE;
+
+		if ((*line[0] == '\0') || (*line[0] == '#'))
+			continue;
+
+		found_hostname = nm_policy_hosts_find_token (*line, hostname);
+		if (found_hostname) {
+			/* Found the current hostname on this line */
+			if (ip4_addr && ip4_addr_matches (*line, ip4_addr)) {
+				found_host4 = TRUE;
+				if (strstr (*line, ADDED_TAG)) {
+					if (!host4_before)
+						host4_before = !found_localhost4;
+				} else {
+					found_user_host4 = TRUE;
+					host4_before = TRUE;  /* Ignore if user added mapping manually */
 				}
-				found_host = TRUE;
+			} else if (!ip4_addr && strstr (*line, ADDED_TAG)) {
+				/* If this is a stale NM-added IPv4 entry we need to remove it,
+				 * so make sure we update /etc/hosts.
+				 */
+				if (is_ip4_addr (*line))
+					no_stale = FALSE;
 			}
 
-			if (is_local_mapping (*line, "localhost")) {
-				/* a 127.0.0.1 line containing 'localhost' */
-				found_localhost = TRUE;
+			if (ip6_addr && ip6_addr_matches (*line, ip6_addr)) {
+				found_host6 = TRUE;
+				if (strstr (*line, ADDED_TAG)) {
+					if (!host6_before)
+						host6_before = !found_localhost6;
+				} else {
+					found_user_host6 = TRUE;
+					host6_before = TRUE;  /* Ignore if user added mapping manually */
+				}
+			} else if (!ip6_addr && strstr (*line, ADDED_TAG)) {
+				/* If this is a stale NM-added IPv6 entry we need to remove it,
+				 * so make sure we update /etc/hosts.
+				 */
+				if (is_ip6_addr (*line))
+					no_stale = FALSE;
 			}
 		}
 
-		if (found_localhost && found_host)
-			return NULL;  /* No update required */
+		if (is_local_mapping (*line, FALSE, "localhost")) {
+			/* a 127.0.0.1 line containing 'localhost' */
+			found_localhost4 = TRUE;
+			custom4 = get_custom_hostnames (*line, hostname, old_hostname, short_hostname, fallback_hostname4);
+			if (!ip4_addr) {
+				/* If there's no IP-specific mapping for the current hostname
+				 * but that hostname is present on in the local mapping line,
+				 * we've found our IPv4 hostname mapping.  If the hostname is
+				 * the fallback *IPv6* hostname it's not going to show up in
+				 * the IPv4 local mapping though, so fake it.
+				 */
+				if (hostname6_is_fallback || found_hostname)
+					found_host4 = TRUE;
+			}
+		} else if (is_local_mapping (*line, TRUE, "localhost6")) {
+			/* a ::1 line containing 'localhost6' */
+			found_localhost6 = TRUE;
+			custom6 = get_custom_hostnames (*line, hostname, old_hostname, short_hostname, fallback_hostname6);
+			if (!ip6_addr) {
+				/* If there's no IP-specific mapping for the current hostname
+				 * but that hostname is present on in the local mapping line,
+				 * we've found our IPv6 hostname mapping.  If the hostname is
+				 * the fallback *IPv4* hostname it's not going to show up in
+				 * the IPv6 local mapping though, so fake it.
+				 */
+				if (hostname4_is_fallback || found_hostname)
+					found_host6 = TRUE;
+			}
+		}
+
+		if (   found_localhost4
+		    && found_host4
+		    && found_localhost6
+		    && found_host6
+		    && host4_before
+		    && host6_before
+		    && no_stale)
+			goto out;  /* No update required */
 	}
 
 	contents = g_string_sized_new (existing_len ? existing_len + 100 : 200);
 	if (!contents) {
 		g_set_error_literal (error, 0, 0, "not enough memory");
-		return NULL;
+		goto out;
 	}
 
-	/* Construct the new hosts file; replace any 127.0.0.1 entry that is at the
-	 * beginning of the file or right after initial comments and contains
-	 * the string 'localhost'.  If there is no 127.0.0.1 entry at the beginning
-	 * or after initial comments that contains 'localhost', add one there
-	 * and ignore any other 127.0.0.1 entries that contain 'localhost'.
+	/* Construct the new hosts file; replace any 127.0.0.1/::1 entry that is
+	 * at the beginning of the file or right after initial comments and contains
+	 * the string 'localhost' (for IPv4) or 'localhost6' (for IPv6).  If there
+	 * is no 127.0.0.1 or ::1 entry at the beginning or after initial comments
+	 * that contains 'localhost' or 'localhost6', add one there
+	 * and ignore any other 127.0.0.1/::1 entries that contain 'localhost' or
+	 * 'localhost6'.
 	 */
 	for (line = lines, initial_comments = TRUE; lines && *line; line++) {
-		gboolean add_line = TRUE;
-
 		/* This is the first line after the initial comments */
 		if (strlen (*line) && initial_comments && (*line[0] != '#')) {
 			initial_comments = FALSE;
 
-			/* If some other line contained the hostname but not 'localhost',
-			 * make a simple localhost mapping and assume the user knows what
-			 * they are doing with their manual hostname entry.  Otherwise if
-			 * the hostname wasn't found somewhere else, add it to the localhost
+			/* If the user added their own mapping for the hostname, just make
+			 * a simple 'localhost' mapping and assume the user knows what they
+			 * are doing with their manual hostname entry.  Otherwise if the
+			 * hostname wasn't found somewhere else, add it to the localhost
 			 * mapping line to make sure it's mapped to something.
 			 */
-			if (found_host_nonlocal)
-				g_string_append (contents, "127.0.0.1");
-			else
-				g_string_append_printf (contents, "127.0.0.1\t%s", hostname);
-
-			if (strcmp (hostname, fallback_hostname)) {
-				g_string_append_printf (contents, "\t%s", fallback_hostname);
-				/* Don't add a standalone 'localhost.localdomain' 127 mapping */
-				if (is_local_mapping (*line, fallback_hostname))
-					add_line = FALSE;
+
+			/* Add the address mappings first so they take precedence */
+			if (!hostname4_is_fallback && ip4_addr && !found_user_host4) {
+				g_string_append_printf (contents, "%s\t%s", ip4_addr, hostname);
+				if (short_hostname)
+					g_string_append_printf (contents, "\t%s", short_hostname);
+				g_string_append_printf (contents, "\t%s\n", ADDED_TAG);
+			}
+			if (!hostname6_is_fallback && ip6_addr && !found_user_host6) {
+				g_string_append_printf (contents, "%s\t%s", ip6_addr, hostname);
+				if (short_hostname)
+					g_string_append_printf (contents, "\t%s", short_hostname);
+				g_string_append_printf (contents, "\t%s\n", ADDED_TAG);
 			}
 
-			g_string_append (contents, "\tlocalhost\n");
-			added = TRUE;
+			/* IPv4 localhost line */
+			g_string_append (contents, "127.0.0.1");
+			if (!hostname4_is_fallback && !ip4_addr && !found_user_host4) {
+				g_string_append_printf (contents, "\t%s", hostname);
+				if (short_hostname)
+					g_string_append_printf (contents, "\t%s", short_hostname);
+			}
+			g_string_append_printf (contents, "\t%s\tlocalhost", fallback_hostname4);
+			if (custom4)
+				g_string_append (contents, custom4);
+			g_string_append_c (contents, '\n');
+
+			/* IPv6 localhost line */
+			g_string_append (contents, "::1");
+			if (!hostname6_is_fallback && !hostname4_is_fallback && !ip6_addr && !found_user_host6) {
+				g_string_append_printf (contents, "\t%s", hostname);
+				if (short_hostname)
+					g_string_append_printf (contents, "\t%s", short_hostname);
+			}
+			g_string_append_printf (contents, "\t%s\tlocalhost6", fallback_hostname6);
+			if (custom6)
+				g_string_append (contents, custom6);
+			g_string_append_c (contents, '\n');
 
-			/* Don't add the original line if it is a 'localhost' mapping */
-			if (is_local_mapping (*line, "localhost"))
-				add_line = FALSE;
+			added = TRUE;
 		}
 
-		if (add_line) {
+		/* Don't add the original line if it is a localhost mapping */
+		if (   !is_local_mapping (*line, FALSE, "localhost")
+		    && !is_local_mapping (*line, FALSE, fallback_hostname4)
+		    && !is_local_mapping (*line, FALSE, hostname)
+		    && !is_local_mapping (*line, TRUE, "localhost6")
+		    && !is_local_mapping (*line, TRUE, fallback_hostname6)
+		    && !is_local_mapping (*line, TRUE, hostname)
+			&& !strstr (*line, ADDED_TAG)) {
+
 			g_string_append (contents, *line);
 			/* Only append the new line if this isn't the last line in the file */
 			if (*(line+1))
@@ -164,17 +446,41 @@ nm_policy_get_etc_hosts (const char **lines,
 
 	/* Hmm, /etc/hosts was empty for some reason */
 	if (!added) {
-		g_string_append (contents, "# Do not remove the following line, or various programs\n");
+		g_string_append (contents, "# Do not remove the following lines, or various programs\n");
 		g_string_append (contents, "# that require network functionality will fail.\n");
-		g_string_append_printf (contents, "127.0.0.1\t%s\tlocalhost\n", fallback_hostname);
+
+		/* Add the address mappings first so they take precedence */
+		if (!hostname4_is_fallback && ip4_addr) {
+			g_string_append_printf (contents, "%s\t%s", ip4_addr, hostname);
+			if (short_hostname)
+				g_string_append_printf (contents, "\t%s", short_hostname);
+			g_string_append_printf (contents, "\t%s\n", ADDED_TAG);
+		}
+		if (!hostname6_is_fallback && ip6_addr) {
+			g_string_append_printf (contents, "%s\t%s", ip6_addr, hostname);
+			if (short_hostname)
+				g_string_append_printf (contents, "\t%s", short_hostname);
+			g_string_append_printf (contents, "\t%s\n", ADDED_TAG);
+		}
+
+		g_string_append_printf (contents, "127.0.0.1\t%s\tlocalhost\n", fallback_hostname4);
+		g_string_append_printf (contents, "::1\t%s\tlocalhost6\n", fallback_hostname6);
 	}
 
+out:
+	g_free (custom4);
+	g_free (custom6);
+	g_free (short_hostname);
 	return contents;
 }
 
 gboolean
 nm_policy_hosts_update_etc_hosts (const char *hostname,
-                                  const char *fallback_hostname,
+                                  const char *old_hostname,
+                                  const char *fallback_hostname4,
+                                  const char *fallback_hostname6,
+                                  const char *ip4_addr,
+                                  const char *ip6_addr,
                                   gboolean *out_changed)
 {
 	char *contents = NULL;
@@ -200,7 +506,11 @@ nm_policy_hosts_update_etc_hosts (const char *hostname,
 	new_contents = nm_policy_get_etc_hosts ((const char **) lines,
 	                                        contents_len,
 	                                        hostname,
-	                                        fallback_hostname,
+	                                        old_hostname,
+	                                        fallback_hostname4,
+	                                        fallback_hostname6,
+	                                        ip4_addr,
+	                                        ip6_addr,
 	                                        &error);
 	g_strfreev (lines);
 	g_free (contents);