diff options
Diffstat (limited to 'src/nm-policy-hosts.c')
| -rw-r--r-- | src/nm-policy-hosts.c | 520 |
1 files changed, 34 insertions, 486 deletions
diff --git a/src/nm-policy-hosts.c b/src/nm-policy-hosts.c index 7f9cff80..8bbd1d3b 100644 --- a/src/nm-policy-hosts.c +++ b/src/nm-policy-hosts.c @@ -20,526 +20,74 @@ #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) -{ - const char *start = line, *p = line; - - g_return_val_if_fail (line != NULL, FALSE); - g_return_val_if_fail (token != NULL, FALSE); - g_return_val_if_fail (strlen (token) > 0, FALSE); - - /* Walk through the line to find the next whitespace character */ - while (p <= line + strlen (line)) { - if (isblank (*p) || (*p == '\0')) { - /* Token starts with 'start' and ends with 'end' */ - if ((p > start) && *start && (p - start == strlen (token)) && !strncmp (start, token, (p - start))) - return TRUE; /* found */ - - /* not found; advance start and continue looking */ - start = p + 1; - } - p++; - } - - return FALSE; -} - -static gboolean -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) -{ - 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 *old_hostname, - const char *fallback_hostname4, - const char *fallback_hostname6, - const char *ip4_addr, - const char *ip6_addr, - GError **error) +nm_policy_get_etc_hosts (const char *contents, gsize contents_len) { - GString *contents = NULL; - const char **line; - 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); - - 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 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 all these things exist we don't need to bother updating the file. - */ - - 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++) { - gboolean found_hostname = FALSE; - - if ((*line[0] == '\0') || (*line[0] == '#')) - continue; + char **lines = NULL, **iter; + GString *new_contents = NULL; - 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 */ - } - } 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 (contents_len == 0 || !strstr (contents, ADDED_TAG)) + return NULL; - 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; - } - } + new_contents = g_string_sized_new (contents_len); - 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; - } + /* Remove "# Added ..." lines */ + lines = g_strsplit_set (contents, "\n\r", -1); + for (iter = lines; iter && *iter; iter++) { + if (!strstr (*iter, ADDED_TAG)) { + g_string_append (new_contents, *iter); + g_string_append_c (new_contents, '\n'); } - - 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"); - goto out; } + g_strfreev (lines); - /* 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'. + /* Remove last blank line at end of file, if one exists; this is + * an artifact of how g_strsplit_set() works. */ - for (line = lines, initial_comments = TRUE; lines && *line; line++) { - /* This is the first line after the initial comments */ - if (strlen (*line) && initial_comments && (*line[0] != '#')) { - initial_comments = FALSE; - - /* 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. - */ - - /* 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); - } + if ( (new_contents->len > 2) + && (new_contents->str[new_contents->len - 1] == '\n')) + g_string_truncate (new_contents, new_contents->len - 1); - /* 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'); - - added = TRUE; - } - - /* 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)) - g_string_append_c (contents, '\n'); - } - } - - /* Hmm, /etc/hosts was empty for some reason */ - if (!added) { - 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"); - - /* 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; + return new_contents; } -gboolean -nm_policy_hosts_update_etc_hosts (const char *hostname, - const char *old_hostname, - const char *fallback_hostname4, - const char *fallback_hostname6, - const char *ip4_addr, - const char *ip6_addr, - gboolean *out_changed) +/* remove any leftover "# Added by NetworkManager" lines */ +void +nm_policy_hosts_clean_etc_hosts (void) { char *contents = NULL; - char **lines = NULL; - GError *error = NULL; - GString *new_contents = NULL; gsize contents_len = 0; - gboolean success = FALSE; - - g_return_val_if_fail (hostname != NULL, FALSE); - g_return_val_if_fail (out_changed != NULL, FALSE); + GError *error = NULL; + GString *new; if (!g_file_get_contents (SYSCONFDIR "/hosts", &contents, &contents_len, &error)) { nm_log_warn (LOGD_DNS, "couldn't read " SYSCONFDIR "/hosts: (%d) %s", error ? error->code : 0, (error && error->message) ? error->message : "(unknown)"); g_clear_error (&error); - return FALSE; + return; } - /* Get the new /etc/hosts contents */ - lines = g_strsplit_set (contents, "\n\r", 0); - new_contents = nm_policy_get_etc_hosts ((const char **) lines, - contents_len, - hostname, - old_hostname, - fallback_hostname4, - fallback_hostname6, - ip4_addr, - ip6_addr, - &error); - g_strfreev (lines); - g_free (contents); - - if (new_contents) { - nm_log_info (LOGD_DNS, "Updating /etc/hosts with new system hostname"); + new = nm_policy_get_etc_hosts (contents, contents_len); + if (new && new->len) { + nm_log_info (LOGD_DNS, "Cleaning leftovers from /etc/hosts"); g_clear_error (&error); - /* And actually update /etc/hosts */ - if (!g_file_set_contents (SYSCONFDIR "/hosts", new_contents->str, -1, &error)) { - nm_log_warn (LOGD_DNS, "couldn't update " SYSCONFDIR "/hosts: (%d) %s", - error ? error->code : 0, - (error && error->message) ? error->message : "(unknown)"); + if (!g_file_set_contents (SYSCONFDIR "/hosts", new->str, -1, &error)) { + nm_log_dbg (LOGD_DNS, "couldn't update " SYSCONFDIR "/hosts: (%d) %s", + error ? error->code : 0, + (error && error->message) ? error->message : "(unknown)"); g_clear_error (&error); - } else { - success = TRUE; - *out_changed = TRUE; } - - g_string_free (new_contents, TRUE); - } else if (!error) { - /* No change required */ - success = TRUE; - } else { - nm_log_warn (LOGD_DNS, "couldn't read " SYSCONFDIR "/hosts: (%d) %s", - error->code, error->message ? error->message : "(unknown)"); - g_clear_error (&error); } - return success; + if (new) + g_string_free (new, TRUE); } |