diff options
| -rw-r--r-- | NEWS | 3 | ||||
| -rw-r--r-- | access.c | 70 | ||||
| -rw-r--r-- | clientserver.c | 2 | ||||
| -rw-r--r-- | loadparm.c | 4 | ||||
| -rw-r--r-- | rsyncd.conf.yo | 20 |
5 files changed, 72 insertions, 27 deletions
@@ -77,6 +77,9 @@ Changes since 3.0.4: - Added the "reverse lookup" parameter to the rsync daemon config file to allow reverse-DNS lookups to be disabled. + - Added a forward-DNS lookup for the daemon's hosts allow/deny config. Can + be disabled via "forward lookup" parameter (defaults to enabled). + - Added a way for more than one group to be specified in the daemon's config file, including a way to specify that you want all of the specified user's groups without having to name them. Also changed the @@ -20,11 +20,47 @@ #include "rsync.h" -static int match_hostname(const char *host, const char *tok) +static int allow_forward_dns; + +extern const char undetermined_hostname[]; + +static int match_hostname(const char **host_ptr, const char *addr, const char *tok) { + struct hostent *hp; + unsigned int i; + const char *host = *host_ptr; + if (!host || !*host) return 0; - return iwildmatch(tok, host); + + /* First check if the reverse-DNS-determined hostname matches. */ + if (iwildmatch(tok, host)) + return 1; + + if (!allow_forward_dns) + return 0; + + /* Fail quietly if tok is an address or wildcarded entry, not a simple hostname. */ + if (!tok[strspn(tok, ".0123456789")] || tok[strcspn(tok, ":/*?[")]) + return 0; + + /* Now try forward-DNS on the token (config-specified hostname) and see if the IP matches. */ + if (!(hp = gethostbyname(tok))) + return 0; + + for (i = 0; hp->h_addr_list[i] != NULL; i++) { + if (strcmp(addr, inet_ntoa(*(struct in_addr*)(hp->h_addr_list[i]))) == 0) { + /* If reverse lookups are off, we'll use the conf-specified + * hostname in preference to UNDETERMINED. */ + if (host == undetermined_hostname) { + if (!(*host_ptr = strdup(tok))) + *host_ptr = undetermined_hostname; + } + return 1; + } + } + + return 0; } static int match_binary(const char *b1, const char *b2, const char *mask, int addrlen) @@ -70,24 +106,16 @@ static int match_address(const char *addr, const char *tok) #endif char mask[16]; char *a = NULL, *t = NULL; - unsigned int len; if (!addr || !*addr) return 0; p = strchr(tok,'/'); - if (p) { + if (p) *p = '\0'; - len = p - tok; - } else - len = strlen(tok); - /* Fail quietly if tok is a hostname (not an address) */ - if (strspn(tok, ".0123456789") != len -#ifdef INET6 - && strchr(tok, ':') == NULL -#endif - ) { + /* Fail quietly if tok is a hostname, not an address. */ + if (tok[strspn(tok, ".0123456789")] && strchr(tok, ':') == NULL) { if (p) *p = '/'; return 0; @@ -210,7 +238,7 @@ static int match_address(const char *addr, const char *tok) return ret; } -static int access_match(const char *list, const char *addr, const char *host) +static int access_match(const char *list, const char *addr, const char **host_ptr) { char *tok; char *list2 = strdup(list); @@ -221,7 +249,7 @@ static int access_match(const char *list, const char *addr, const char *host) strlower(list2); for (tok = strtok(list2, " ,\t"); tok; tok = strtok(NULL, " ,\t")) { - if (match_hostname(host, tok) || match_address(addr, tok)) { + if (match_hostname(host_ptr, addr, tok) || match_address(addr, tok)) { free(list2); return 1; } @@ -231,17 +259,21 @@ static int access_match(const char *list, const char *addr, const char *host) return 0; } -int allow_access(const char *addr, const char *host, - const char *allow_list, const char *deny_list) +int allow_access(const char *addr, const char **host_ptr, int i) { + const char *allow_list = lp_hosts_allow(i); + const char *deny_list = lp_hosts_deny(i); + if (allow_list && !*allow_list) allow_list = NULL; if (deny_list && !*deny_list) deny_list = NULL; + allow_forward_dns = lp_forward_lookup(i); + /* If we match an allow-list item, we always allow access. */ if (allow_list) { - if (access_match(allow_list, addr, host)) + if (access_match(allow_list, addr, host_ptr)) return 1; /* For an allow-list w/o a deny-list, disallow non-matches. */ if (!deny_list) @@ -250,7 +282,7 @@ int allow_access(const char *addr, const char *host, /* If we match a deny-list item (and got past any allow-list * items), we always disallow access. */ - if (deny_list && access_match(deny_list, addr, host)) + if (deny_list && access_match(deny_list, addr, host_ptr)) return 0; /* Allow all other access. */ diff --git a/clientserver.c b/clientserver.c index 21ef01c5..8b6b896f 100644 --- a/clientserver.c +++ b/clientserver.c @@ -515,7 +515,7 @@ static int rsync_module(int f_in, int f_out, int i, const char *addr, const char set_env_str("RSYNC_HOST_NAME", host); set_env_str("RSYNC_HOST_ADDR", addr); - if (!allow_access(addr, host, lp_hosts_allow(i), lp_hosts_deny(i))) { + if (!allow_access(addr, &host, i)) { rprintf(FLOG, "rsync denied on module %s from %s (%s)\n", name, host, addr); if (!lp_list(i)) @@ -139,6 +139,7 @@ typedef struct { int timeout; BOOL fake_super; + BOOL forward_lookup; BOOL ignore_errors; BOOL ignore_nonreadable; BOOL list; @@ -211,6 +212,7 @@ static const all_vars Defaults = { /* timeout; */ 0, /* fake_super; */ False, + /* forward_lookup; */ True, /* ignore_errors; */ False, /* ignore_nonreadable; */ False, /* list; */ True, @@ -322,6 +324,7 @@ static struct parm_struct parm_table[] = {"exclude", P_STRING, P_LOCAL, &Vars.l.exclude, NULL,0}, {"fake super", P_BOOL, P_LOCAL, &Vars.l.fake_super, NULL,0}, {"filter", P_STRING, P_LOCAL, &Vars.l.filter, NULL,0}, + {"forward lookup", P_BOOL, P_LOCAL, &Vars.l.forward_lookup, NULL,0}, {"gid", P_STRING, P_LOCAL, &Vars.l.gid, NULL,0}, {"hosts allow", P_STRING, P_LOCAL, &Vars.l.hosts_allow, NULL,0}, {"hosts deny", P_STRING, P_LOCAL, &Vars.l.hosts_deny, NULL,0}, @@ -476,6 +479,7 @@ FN_LOCAL_INTEGER(lp_syslog_facility, syslog_facility) FN_LOCAL_INTEGER(lp_timeout, timeout) FN_LOCAL_BOOL(lp_fake_super, fake_super) +FN_LOCAL_BOOL(lp_forward_lookup, forward_lookup) FN_LOCAL_BOOL(lp_ignore_errors, ignore_errors) FN_LOCAL_BOOL(lp_ignore_nonreadable, ignore_nonreadable) FN_LOCAL_BOOL(lp_list, list) diff --git a/rsyncd.conf.yo b/rsyncd.conf.yo index f96fc9e1..2dbf67c5 100644 --- a/rsyncd.conf.yo +++ b/rsyncd.conf.yo @@ -532,13 +532,14 @@ quote(itemization( IP address and maskaddr is the netmask in dotted decimal notation for IPv4, or similar for IPv6, e.g. ffff:ffff:ffff:ffff:: instead of /64. All IP addresses which match the masked IP address will be allowed in. - it() a hostname. The hostname as determined by a reverse lookup will - be matched (case insensitive) against the pattern. Only an exact - match is allowed in. This only works if "reverse lookup" is enabled - (the default). - it() a hostname pattern using wildcards. These are matched using the - same rules as normal unix filename matching. If the pattern matches - then the client is allowed in. + it() a hostname pattern using wildcards. If the hostname of the connecting IP + (as determined by a reverse lookup) matches the wildcarded name (using the + same rules as normal unix filename matching), the client is allowed in. This + only works if "reverse lookup" is enabled (the default). + it() a hostname. A plain hostname is matched against the reverse DNS of the + connecting IP (if "reverse lookup" is enabled), and/or the IP of the given + hostname is matched against the connecting IP (if "forward lookup" is + enabled, as it is by default). Any match will be allowed in. )) Note IPv6 link-local addresses can have a scope in the address specification: @@ -578,6 +579,11 @@ lookup as soon as a client connects, so disabling it for a module will not avoid the lookup. Thus, you probably want to disable it globally and then enable it for modules that need the information. +dit(bf(forward lookup)) Controls whether the daemon performs a forward lookup +on any hostname specified in an hosts allow/deny setting. By default this is +enabled, allowing the use of an explicit hostname that would not be returned +by reverse DNS of the connecting IP. + dit(bf(ignore errors)) This parameter tells rsyncd to ignore I/O errors on the daemon when deciding whether to run the delete phase of the transfer. Normally rsync skips the bf(--delete) step if any |