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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-10 19:59:03 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-10 19:59:03 +0000
commita848231ae0f346dc7cc000973fbeb65b0894ee92 (patch)
tree44b60b367c86723cc78383ef247885d72b388afe /src/proxymap/proxymap.c
parentInitial commit. (diff)
downloadpostfix-a848231ae0f346dc7cc000973fbeb65b0894ee92.tar.xz
postfix-a848231ae0f346dc7cc000973fbeb65b0894ee92.zip
Adding upstream version 3.8.5.upstream/3.8.5
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/proxymap/proxymap.c')
-rw-r--r--src/proxymap/proxymap.c851
1 files changed, 851 insertions, 0 deletions
diff --git a/src/proxymap/proxymap.c b/src/proxymap/proxymap.c
new file mode 100644
index 0000000..abdcf3a
--- /dev/null
+++ b/src/proxymap/proxymap.c
@@ -0,0 +1,851 @@
+/*++
+/* NAME
+/* proxymap 8
+/* SUMMARY
+/* Postfix lookup table proxy server
+/* SYNOPSIS
+/* \fBproxymap\fR [generic Postfix daemon options]
+/* DESCRIPTION
+/* The \fBproxymap\fR(8) server provides read-only or read-write
+/* table lookup service to Postfix processes. These services are
+/* implemented with distinct service names: \fBproxymap\fR and
+/* \fBproxywrite\fR, respectively. The purpose of these services is:
+/* .IP \(bu
+/* To overcome chroot restrictions. For example, a chrooted SMTP
+/* server needs access to the system passwd file in order to
+/* reject mail for non-existent local addresses, but it is not
+/* practical to maintain a copy of the passwd file in the chroot
+/* jail. The solution:
+/* .sp
+/* .nf
+/* local_recipient_maps =
+/* proxy:unix:passwd.byname $alias_maps
+/* .fi
+/* .IP \(bu
+/* To consolidate the number of open lookup tables by sharing
+/* one open table among multiple processes. For example, making
+/* mysql connections from every Postfix daemon process results
+/* in "too many connections" errors. The solution:
+/* .sp
+/* .nf
+/* virtual_alias_maps =
+/* proxy:mysql:/etc/postfix/virtual_alias.cf
+/* .fi
+/* .sp
+/* The total number of connections is limited by the number of
+/* proxymap server processes.
+/* .IP \(bu
+/* To provide single-updater functionality for lookup tables
+/* that do not reliably support multiple writers (i.e. all
+/* file-based tables).
+/* .PP
+/* The \fBproxymap\fR(8) server implements the following requests:
+/* .IP "\fBopen\fR \fImaptype:mapname flags\fR"
+/* Open the table with type \fImaptype\fR and name \fImapname\fR,
+/* as controlled by \fIflags\fR. The reply includes the \fImaptype\fR
+/* dependent flags (to distinguish a fixed string table from a regular
+/* expression table).
+/* .IP "\fBlookup\fR \fImaptype:mapname flags key\fR"
+/* Look up the data stored under the requested key.
+/* The reply is the request completion status code and
+/* the lookup result value.
+/* The \fImaptype:mapname\fR and \fIflags\fR are the same
+/* as with the \fBopen\fR request.
+/* .IP "\fBupdate\fR \fImaptype:mapname flags key value\fR"
+/* Update the data stored under the requested key.
+/* The reply is the request completion status code.
+/* The \fImaptype:mapname\fR and \fIflags\fR are the same
+/* as with the \fBopen\fR request.
+/* .sp
+/* To implement single-updater maps, specify a process limit
+/* of 1 in the master.cf file entry for the \fBproxywrite\fR
+/* service.
+/* .sp
+/* This request is supported in Postfix 2.5 and later.
+/* .IP "\fBdelete\fR \fImaptype:mapname flags key\fR"
+/* Delete the data stored under the requested key.
+/* The reply is the request completion status code.
+/* The \fImaptype:mapname\fR and \fIflags\fR are the same
+/* as with the \fBopen\fR request.
+/* .sp
+/* This request is supported in Postfix 2.5 and later.
+/* .IP "\fBsequence\fR \fImaptype:mapname flags function\fR"
+/* Iterate over the specified database. The \fIfunction\fR
+/* is one of DICT_SEQ_FUN_FIRST or DICT_SEQ_FUN_NEXT.
+/* The reply is the request completion status code and
+/* a lookup key and result value, if found.
+/* .sp
+/* This request is supported in Postfix 2.9 and later.
+/* .PP
+/* The request completion status is one of OK, RETRY, NOKEY
+/* (lookup failed because the key was not found), BAD (malformed
+/* request) or DENY (the table is not approved for proxy read
+/* or update access).
+/*
+/* There is no \fBclose\fR command, nor are tables implicitly closed
+/* when a client disconnects. The purpose is to share tables among
+/* multiple client processes.
+/* SERVER PROCESS MANAGEMENT
+/* .ad
+/* .fi
+/* \fBproxymap\fR(8) servers run under control by the Postfix
+/* \fBmaster\fR(8)
+/* server. Each server can handle multiple simultaneous connections.
+/* When all servers are busy while a client connects, the \fBmaster\fR(8)
+/* creates a new \fBproxymap\fR(8) server process, provided that the
+/* process limit is not exceeded.
+/* Each server terminates after serving at least \fB$max_use\fR clients
+/* or after \fB$max_idle\fR seconds of idle time.
+/* SECURITY
+/* .ad
+/* .fi
+/* The \fBproxymap\fR(8) server opens only tables that are
+/* approved via the \fBproxy_read_maps\fR or \fBproxy_write_maps\fR
+/* configuration parameters, does not talk to
+/* users, and can run at fixed low privilege, chrooted or not.
+/* However, running the proxymap server chrooted severely limits
+/* usability, because it can open only chrooted tables.
+/*
+/* The \fBproxymap\fR(8) server is not a trusted daemon process, and must
+/* not be used to look up sensitive information such as UNIX user or
+/* group IDs, mailbox file/directory names or external commands.
+/*
+/* In Postfix version 2.2 and later, the proxymap client recognizes
+/* requests to access a table for security-sensitive purposes,
+/* and opens the table directly. This allows the same main.cf
+/* setting to be used by sensitive and non-sensitive processes.
+/*
+/* Postfix-writable data files should be stored under a dedicated
+/* directory that is writable only by the Postfix mail system,
+/* such as the Postfix-owned \fBdata_directory\fR.
+/*
+/* In particular, Postfix-writable files should never exist
+/* in root-owned directories. That would open up a particular
+/* type of security hole where ownership of a file or directory
+/* does not match the provider of its content.
+/* DIAGNOSTICS
+/* Problems and transactions are logged to \fBsyslogd\fR(8)
+/* or \fBpostlogd\fR(8).
+/* BUGS
+/* The \fBproxymap\fR(8) server provides service to multiple clients,
+/* and must therefore not be used for tables that have high-latency
+/* lookups.
+/*
+/* The \fBproxymap\fR(8) read-write service does not explicitly
+/* close lookup tables (even if it did, this could not be relied on,
+/* because the process may be terminated between table updates).
+/* The read-write service should therefore not be used with tables that
+/* leave persistent storage in an inconsistent state between
+/* updates (for example, CDB). Tables that support "sync on
+/* update" should be safe (for example, Berkeley DB) as should
+/* tables that are implemented by a real DBMS.
+/* CONFIGURATION PARAMETERS
+/* .ad
+/* .fi
+/* On busy mail systems a long time may pass before
+/* \fBproxymap\fR(8) relevant
+/* changes to \fBmain.cf\fR are picked up. Use the command
+/* "\fBpostfix reload\fR" to speed up a change.
+/*
+/* The text below provides only a parameter summary. See
+/* \fBpostconf\fR(5) for more details including examples.
+/* .IP "\fBconfig_directory (see 'postconf -d' output)\fR"
+/* The default location of the Postfix main.cf and master.cf
+/* configuration files.
+/* .IP "\fBdata_directory (see 'postconf -d' output)\fR"
+/* The directory with Postfix-writable data files (for example:
+/* caches, pseudo-random numbers).
+/* .IP "\fBdaemon_timeout (18000s)\fR"
+/* How much time a Postfix daemon process may take to handle a
+/* request before it is terminated by a built-in watchdog timer.
+/* .IP "\fBipc_timeout (3600s)\fR"
+/* The time limit for sending or receiving information over an internal
+/* communication channel.
+/* .IP "\fBmax_idle (100s)\fR"
+/* The maximum amount of time that an idle Postfix daemon process waits
+/* for an incoming connection before terminating voluntarily.
+/* .IP "\fBmax_use (100)\fR"
+/* The maximal number of incoming connections that a Postfix daemon
+/* process will service before terminating voluntarily.
+/* .IP "\fBprocess_id (read-only)\fR"
+/* The process ID of a Postfix command or daemon process.
+/* .IP "\fBprocess_name (read-only)\fR"
+/* The process name of a Postfix command or daemon process.
+/* .IP "\fBproxy_read_maps (see 'postconf -d' output)\fR"
+/* The lookup tables that the \fBproxymap\fR(8) server is allowed to
+/* access for the read-only service.
+/* .PP
+/* Available in Postfix 2.5 and later:
+/* .IP "\fBdata_directory (see 'postconf -d' output)\fR"
+/* The directory with Postfix-writable data files (for example:
+/* caches, pseudo-random numbers).
+/* .IP "\fBproxy_write_maps (see 'postconf -d' output)\fR"
+/* The lookup tables that the \fBproxymap\fR(8) server is allowed to
+/* access for the read-write service.
+/* .PP
+/* Available in Postfix 3.3 and later:
+/* .IP "\fBservice_name (read-only)\fR"
+/* The master.cf service name of a Postfix daemon process.
+/* SEE ALSO
+/* postconf(5), configuration parameters
+/* master(5), generic daemon options
+/* README FILES
+/* .ad
+/* .fi
+/* Use "\fBpostconf readme_directory\fR" or
+/* "\fBpostconf html_directory\fR" to locate this information.
+/* .na
+/* .nf
+/* DATABASE_README, Postfix lookup table overview
+/* LICENSE
+/* .ad
+/* .fi
+/* The Secure Mailer license must be distributed with this software.
+/* HISTORY
+/* .ad
+/* .fi
+/* The proxymap service was introduced with Postfix 2.0.
+/* AUTHOR(S)
+/* Wietse Venema
+/* IBM T.J. Watson Research
+/* P.O. Box 704
+/* Yorktown Heights, NY 10598, USA
+/*
+/* Wietse Venema
+/* Google, Inc.
+/* 111 8th Avenue
+/* New York, NY 10011, USA
+/*--*/
+
+/* System library. */
+
+#include <sys_defs.h>
+#include <string.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+/* Utility library. */
+
+#include <msg.h>
+#include <mymalloc.h>
+#include <vstring.h>
+#include <htable.h>
+#include <stringops.h>
+#include <dict.h>
+#include <dict_pipe.h>
+#include <dict_union.h>
+
+/* Global library. */
+
+#include <mail_conf.h>
+#include <mail_params.h>
+#include <mail_version.h>
+#include <mail_proto.h>
+#include <dict_proxy.h>
+
+/* Server skeleton. */
+
+#include <mail_server.h>
+
+/* Application-specific. */
+
+ /*
+ * XXX All but the last are needed here so that $name expansion dependencies
+ * aren't too broken. The fix is to gather all parameter default settings in
+ * one place.
+ */
+char *var_alias_maps;
+char *var_local_rcpt_maps;
+char *var_virt_alias_maps;
+char *var_virt_alias_doms;
+char *var_virt_mailbox_maps;
+char *var_virt_mailbox_doms;
+char *var_relay_rcpt_maps;
+char *var_canonical_maps;
+char *var_send_canon_maps;
+char *var_rcpt_canon_maps;
+char *var_relocated_maps;
+char *var_transport_maps;
+char *var_verify_map;
+char *var_smtpd_snd_auth_maps;
+char *var_psc_cache_map;
+char *var_proxy_read_maps;
+char *var_proxy_write_maps;
+
+ /*
+ * The pre-approved, pre-parsed list of maps.
+ */
+static HTABLE *proxy_auth_maps;
+
+ /*
+ * Shared and static to reduce memory allocation overhead.
+ */
+static VSTRING *request;
+static VSTRING *request_map;
+static VSTRING *request_key;
+static VSTRING *request_value;
+static VSTRING *map_type_name_flags;
+
+ /*
+ * Are we a proxy writer or not?
+ */
+static int proxy_writer;
+
+ /*
+ * Silly little macros.
+ */
+#define STR(x) vstring_str(x)
+#define VSTREQ(x,y) (strcmp(STR(x),y) == 0)
+
+/* get_nested_dict_name - return nested dictionary name pointer, or null */
+
+static char *get_nested_dict_name(char *type_name)
+{
+ const struct {
+ const char *type_col;
+ ssize_t type_col_len;
+ } *prefix, prefixes[] = {
+ DICT_TYPE_UNION ":", (sizeof(DICT_TYPE_UNION ":") - 1),
+ DICT_TYPE_PIPE ":", (sizeof(DICT_TYPE_PIPE ":") - 1),
+ };
+
+#define COUNT_OF(x) (sizeof(x)/sizeof((x)[0]))
+
+ for (prefix = prefixes; prefix < prefixes + COUNT_OF(prefixes); prefix++) {
+ if (strncmp(type_name, prefix->type_col, prefix->type_col_len) == 0)
+ return (type_name + prefix->type_col_len);
+ }
+ return (0);
+}
+
+/* proxy_map_find - look up or open table */
+
+static DICT *proxy_map_find(const char *map_type_name, int request_flags,
+ int *statp)
+{
+ DICT *dict;
+
+#define PROXY_COLON DICT_TYPE_PROXY ":"
+#define PROXY_COLON_LEN (sizeof(PROXY_COLON) - 1)
+#define READ_OPEN_FLAGS O_RDONLY
+#define WRITE_OPEN_FLAGS (O_RDWR | O_CREAT)
+
+ /*
+ * Canonicalize the map name. If the map is not on the approved list,
+ * deny the request.
+ */
+#define PROXY_MAP_FIND_ERROR_RETURN(x) { *statp = (x); return (0); }
+#define PROXY_MAP_PARAM_NAME(proxy_writer) \
+ ((proxy_writer) == 0 ? VAR_PROXY_READ_MAPS : VAR_PROXY_WRITE_MAPS)
+
+ while (strncmp(map_type_name, PROXY_COLON, PROXY_COLON_LEN) == 0)
+ map_type_name += PROXY_COLON_LEN;
+ /* XXX The following breaks with maps that have ':' in their name. */
+ if (strchr(map_type_name, ':') == 0)
+ PROXY_MAP_FIND_ERROR_RETURN(PROXY_STAT_BAD);
+ if (htable_locate(proxy_auth_maps, map_type_name) == 0) {
+ msg_warn("request for unapproved table: \"%s\"", map_type_name);
+ msg_warn("to approve this table for %s access, list %s:%s in %s:%s",
+ proxy_writer == 0 ? "read-only" : "read-write",
+ DICT_TYPE_PROXY, map_type_name, MAIN_CONF_FILE,
+ PROXY_MAP_PARAM_NAME(proxy_writer));
+ PROXY_MAP_FIND_ERROR_RETURN(PROXY_STAT_DENY);
+ }
+
+ /*
+ * Open one instance of a map for each combination of name+flags.
+ *
+ * Assume that a map instance can be shared among clients with different
+ * paranoia flag settings and with different map lookup flag settings.
+ *
+ * XXX The open() flags are passed implicitly, via the selection of the
+ * service name. For a more sophisticated interface, appropriate subsets
+ * of open() flags should be received directly from the client.
+ */
+ vstring_sprintf(map_type_name_flags, "%s:%s", map_type_name,
+ dict_flags_str(request_flags & DICT_FLAG_INST_MASK));
+ if (msg_verbose)
+ msg_info("proxy_map_find: %s", STR(map_type_name_flags));
+ if ((dict = dict_handle(STR(map_type_name_flags))) == 0) {
+ dict = dict_open(map_type_name, proxy_writer ?
+ WRITE_OPEN_FLAGS : READ_OPEN_FLAGS,
+ request_flags);
+ if (dict == 0)
+ msg_panic("proxy_map_find: dict_open null result");
+ dict_register(STR(map_type_name_flags), dict);
+ }
+ dict->error = 0;
+ return (dict);
+}
+
+/* proxymap_sequence_service - remote sequence service */
+
+static void proxymap_sequence_service(VSTREAM *client_stream)
+{
+ int request_flags;
+ DICT *dict;
+ int request_func;
+ const char *reply_key;
+ const char *reply_value;
+ int dict_status;
+ int reply_status;
+
+ /*
+ * Process the request.
+ */
+ if (attr_scan(client_stream, ATTR_FLAG_STRICT,
+ RECV_ATTR_STR(MAIL_ATTR_TABLE, request_map),
+ RECV_ATTR_INT(MAIL_ATTR_FLAGS, &request_flags),
+ RECV_ATTR_INT(MAIL_ATTR_FUNC, &request_func),
+ ATTR_TYPE_END) != 3
+ || (request_func != DICT_SEQ_FUN_FIRST
+ && request_func != DICT_SEQ_FUN_NEXT)) {
+ reply_status = PROXY_STAT_BAD;
+ reply_key = reply_value = "";
+ } else if ((dict = proxy_map_find(STR(request_map), request_flags,
+ &reply_status)) == 0) {
+ reply_key = reply_value = "";
+ } else {
+ dict->flags = ((dict->flags & ~DICT_FLAG_RQST_MASK)
+ | (request_flags & DICT_FLAG_RQST_MASK));
+ dict_status = dict_seq(dict, request_func, &reply_key, &reply_value);
+ if (dict_status == 0) {
+ reply_status = PROXY_STAT_OK;
+ } else if (dict->error == 0) {
+ reply_status = PROXY_STAT_NOKEY;
+ reply_key = reply_value = "";
+ } else {
+ reply_status = (dict->error == DICT_ERR_RETRY ?
+ PROXY_STAT_RETRY : PROXY_STAT_CONFIG);
+ reply_key = reply_value = "";
+ }
+ }
+
+ /*
+ * Respond to the client.
+ */
+ attr_print(client_stream, ATTR_FLAG_NONE,
+ SEND_ATTR_INT(MAIL_ATTR_STATUS, reply_status),
+ SEND_ATTR_STR(MAIL_ATTR_KEY, reply_key),
+ SEND_ATTR_STR(MAIL_ATTR_VALUE, reply_value),
+ ATTR_TYPE_END);
+}
+
+/* proxymap_lookup_service - remote lookup service */
+
+static void proxymap_lookup_service(VSTREAM *client_stream)
+{
+ int request_flags;
+ DICT *dict;
+ const char *reply_value;
+ int reply_status;
+
+ /*
+ * Process the request.
+ */
+ if (attr_scan(client_stream, ATTR_FLAG_STRICT,
+ RECV_ATTR_STR(MAIL_ATTR_TABLE, request_map),
+ RECV_ATTR_INT(MAIL_ATTR_FLAGS, &request_flags),
+ RECV_ATTR_STR(MAIL_ATTR_KEY, request_key),
+ ATTR_TYPE_END) != 3) {
+ reply_status = PROXY_STAT_BAD;
+ reply_value = "";
+ } else if ((dict = proxy_map_find(STR(request_map), request_flags,
+ &reply_status)) == 0) {
+ reply_value = "";
+ } else if (dict->flags = ((dict->flags & ~DICT_FLAG_RQST_MASK)
+ | (request_flags & DICT_FLAG_RQST_MASK)),
+ (reply_value = dict_get(dict, STR(request_key))) != 0) {
+ reply_status = PROXY_STAT_OK;
+ } else if (dict->error == 0) {
+ reply_status = PROXY_STAT_NOKEY;
+ reply_value = "";
+ } else {
+ reply_status = (dict->error == DICT_ERR_RETRY ?
+ PROXY_STAT_RETRY : PROXY_STAT_CONFIG);
+ reply_value = "";
+ }
+
+ /*
+ * Respond to the client.
+ */
+ attr_print(client_stream, ATTR_FLAG_NONE,
+ SEND_ATTR_INT(MAIL_ATTR_STATUS, reply_status),
+ SEND_ATTR_STR(MAIL_ATTR_VALUE, reply_value),
+ ATTR_TYPE_END);
+}
+
+/* proxymap_update_service - remote update service */
+
+static void proxymap_update_service(VSTREAM *client_stream)
+{
+ int request_flags;
+ DICT *dict;
+ int dict_status;
+ int reply_status;
+
+ /*
+ * Process the request.
+ *
+ * XXX We don't close maps, so we must turn on synchronous update to ensure
+ * that the on-disk data is in a consistent state between updates.
+ *
+ * XXX We ignore duplicates, because the proxymap server would abort
+ * otherwise.
+ */
+ if (attr_scan(client_stream, ATTR_FLAG_STRICT,
+ RECV_ATTR_STR(MAIL_ATTR_TABLE, request_map),
+ RECV_ATTR_INT(MAIL_ATTR_FLAGS, &request_flags),
+ RECV_ATTR_STR(MAIL_ATTR_KEY, request_key),
+ RECV_ATTR_STR(MAIL_ATTR_VALUE, request_value),
+ ATTR_TYPE_END) != 4) {
+ reply_status = PROXY_STAT_BAD;
+ } else if (proxy_writer == 0) {
+ msg_warn("refusing %s update request on non-%s service",
+ STR(request_map), MAIL_SERVICE_PROXYWRITE);
+ reply_status = PROXY_STAT_DENY;
+ } else if ((dict = proxy_map_find(STR(request_map), request_flags,
+ &reply_status)) == 0) {
+ /* void */ ;
+ } else {
+ dict->flags = ((dict->flags & ~DICT_FLAG_RQST_MASK)
+ | (request_flags & DICT_FLAG_RQST_MASK)
+ | DICT_FLAG_SYNC_UPDATE | DICT_FLAG_DUP_REPLACE);
+ dict_status = dict_put(dict, STR(request_key), STR(request_value));
+ if (dict_status == 0) {
+ reply_status = PROXY_STAT_OK;
+ } else if (dict->error == 0) {
+ reply_status = PROXY_STAT_NOKEY;
+ } else {
+ reply_status = (dict->error == DICT_ERR_RETRY ?
+ PROXY_STAT_RETRY : PROXY_STAT_CONFIG);
+ }
+ }
+
+ /*
+ * Respond to the client.
+ */
+ attr_print(client_stream, ATTR_FLAG_NONE,
+ SEND_ATTR_INT(MAIL_ATTR_STATUS, reply_status),
+ ATTR_TYPE_END);
+}
+
+/* proxymap_delete_service - remote delete service */
+
+static void proxymap_delete_service(VSTREAM *client_stream)
+{
+ int request_flags;
+ DICT *dict;
+ int dict_status;
+ int reply_status;
+
+ /*
+ * Process the request.
+ *
+ * XXX We don't close maps, so we must turn on synchronous update to ensure
+ * that the on-disk data is in a consistent state between updates.
+ */
+ if (attr_scan(client_stream, ATTR_FLAG_STRICT,
+ RECV_ATTR_STR(MAIL_ATTR_TABLE, request_map),
+ RECV_ATTR_INT(MAIL_ATTR_FLAGS, &request_flags),
+ RECV_ATTR_STR(MAIL_ATTR_KEY, request_key),
+ ATTR_TYPE_END) != 3) {
+ reply_status = PROXY_STAT_BAD;
+ } else if (proxy_writer == 0) {
+ msg_warn("refusing %s delete request on non-%s service",
+ STR(request_map), MAIL_SERVICE_PROXYWRITE);
+ reply_status = PROXY_STAT_DENY;
+ } else if ((dict = proxy_map_find(STR(request_map), request_flags,
+ &reply_status)) == 0) {
+ /* void */ ;
+ } else {
+ dict->flags = ((dict->flags & ~DICT_FLAG_RQST_MASK)
+ | (request_flags & DICT_FLAG_RQST_MASK)
+ | DICT_FLAG_SYNC_UPDATE);
+ dict_status = dict_del(dict, STR(request_key));
+ if (dict_status == 0) {
+ reply_status = PROXY_STAT_OK;
+ } else if (dict->error == 0) {
+ reply_status = PROXY_STAT_NOKEY;
+ } else {
+ reply_status = (dict->error == DICT_ERR_RETRY ?
+ PROXY_STAT_RETRY : PROXY_STAT_CONFIG);
+ }
+ }
+
+ /*
+ * Respond to the client.
+ */
+ attr_print(client_stream, ATTR_FLAG_NONE,
+ SEND_ATTR_INT(MAIL_ATTR_STATUS, reply_status),
+ ATTR_TYPE_END);
+}
+
+/* proxymap_open_service - open remote lookup table */
+
+static void proxymap_open_service(VSTREAM *client_stream)
+{
+ int request_flags;
+ DICT *dict;
+ int reply_status;
+ int reply_flags;
+
+ /*
+ * Process the request.
+ */
+ if (attr_scan(client_stream, ATTR_FLAG_STRICT,
+ RECV_ATTR_STR(MAIL_ATTR_TABLE, request_map),
+ RECV_ATTR_INT(MAIL_ATTR_FLAGS, &request_flags),
+ ATTR_TYPE_END) != 2) {
+ reply_status = PROXY_STAT_BAD;
+ reply_flags = 0;
+ } else if ((dict = proxy_map_find(STR(request_map), request_flags,
+ &reply_status)) == 0) {
+ reply_flags = 0;
+ } else {
+ reply_status = PROXY_STAT_OK;
+ reply_flags = dict->flags;
+ }
+
+ /*
+ * Respond to the client.
+ */
+ attr_print(client_stream, ATTR_FLAG_NONE,
+ SEND_ATTR_INT(MAIL_ATTR_STATUS, reply_status),
+ SEND_ATTR_INT(MAIL_ATTR_FLAGS, reply_flags),
+ ATTR_TYPE_END);
+}
+
+/* proxymap_service - perform service for client */
+
+static void proxymap_service(VSTREAM *client_stream, char *unused_service,
+ char **argv)
+{
+
+ /*
+ * Sanity check. This service takes no command-line arguments.
+ */
+ if (argv[0])
+ msg_fatal("unexpected command-line argument: %s", argv[0]);
+
+ /*
+ * Deadline enforcement.
+ */
+ if (vstream_fstat(client_stream, VSTREAM_FLAG_DEADLINE) == 0)
+ vstream_control(client_stream,
+ CA_VSTREAM_CTL_TIMEOUT(1),
+ CA_VSTREAM_CTL_END);
+
+ /*
+ * This routine runs whenever a client connects to the socket dedicated
+ * to the proxymap service. All connection-management stuff is handled by
+ * the common code in multi_server.c.
+ */
+ vstream_control(client_stream,
+ CA_VSTREAM_CTL_START_DEADLINE,
+ CA_VSTREAM_CTL_END);
+ if (attr_scan(client_stream,
+ ATTR_FLAG_MORE | ATTR_FLAG_STRICT,
+ RECV_ATTR_STR(MAIL_ATTR_REQ, request),
+ ATTR_TYPE_END) == 1) {
+ if (VSTREQ(request, PROXY_REQ_LOOKUP)) {
+ proxymap_lookup_service(client_stream);
+ } else if (VSTREQ(request, PROXY_REQ_UPDATE)) {
+ proxymap_update_service(client_stream);
+ } else if (VSTREQ(request, PROXY_REQ_DELETE)) {
+ proxymap_delete_service(client_stream);
+ } else if (VSTREQ(request, PROXY_REQ_SEQUENCE)) {
+ proxymap_sequence_service(client_stream);
+ } else if (VSTREQ(request, PROXY_REQ_OPEN)) {
+ proxymap_open_service(client_stream);
+ } else {
+ msg_warn("unrecognized request: \"%s\", ignored", STR(request));
+ attr_print(client_stream, ATTR_FLAG_NONE,
+ SEND_ATTR_INT(MAIL_ATTR_STATUS, PROXY_STAT_BAD),
+ ATTR_TYPE_END);
+ }
+ }
+ vstream_control(client_stream,
+ CA_VSTREAM_CTL_START_DEADLINE,
+ CA_VSTREAM_CTL_END);
+ vstream_fflush(client_stream);
+}
+
+/* dict_proxy_open - intercept remote map request from inside library */
+
+DICT *dict_proxy_open(const char *map, int open_flags, int dict_flags)
+{
+ if (msg_verbose)
+ msg_info("dict_proxy_open(%s, 0%o, 0%o) called from internal routine",
+ map, open_flags, dict_flags);
+ while (strncmp(map, PROXY_COLON, PROXY_COLON_LEN) == 0)
+ map += PROXY_COLON_LEN;
+ return (dict_open(map, open_flags, dict_flags));
+}
+
+/* authorize_proxied_maps - recursively authorize maps */
+
+static void authorize_proxied_maps(char *bp)
+{
+ const char *sep = CHARS_COMMA_SP;
+ const char *parens = CHARS_BRACE;
+ char *type_name;
+
+ while ((type_name = mystrtokq(&bp, sep, parens)) != 0) {
+ char *nested_info;
+
+ /* Maybe { maptype:mapname attr=value... } */
+ if (*type_name == parens[0]) {
+ char *err;
+
+ /* Warn about blatant syntax error. */
+ if ((err = extpar(&type_name, parens, EXTPAR_FLAG_NONE)) != 0) {
+ msg_warn("bad %s parameter value: %s",
+ PROXY_MAP_PARAM_NAME(proxy_writer), err);
+ myfree(err);
+ continue;
+ }
+ /* Don't try to second-guess the semantics of { }. */
+ if ((type_name = mystrtokq(&type_name, sep, parens)) == 0)
+ continue;
+ }
+ /* Recurse into nested map (pipemap, unionmap). */
+ if ((nested_info = get_nested_dict_name(type_name)) != 0) {
+ char *err;
+
+ if (*nested_info != parens[0])
+ continue;
+ /* Warn about blatant syntax error. */
+ if ((err = extpar(&nested_info, parens, EXTPAR_FLAG_NONE)) != 0) {
+ msg_warn("bad %s parameter value: %s",
+ PROXY_MAP_PARAM_NAME(proxy_writer), err);
+ myfree(err);
+ continue;
+ }
+ authorize_proxied_maps(nested_info);
+ continue;
+ }
+ if (strncmp(type_name, PROXY_COLON, PROXY_COLON_LEN))
+ continue;
+ do {
+ type_name += PROXY_COLON_LEN;
+ } while (!strncmp(type_name, PROXY_COLON, PROXY_COLON_LEN));
+ if (strchr(type_name, ':') != 0
+ && htable_locate(proxy_auth_maps, type_name) == 0) {
+ (void) htable_enter(proxy_auth_maps, type_name, (void *) 0);
+ if (msg_verbose)
+ msg_info("allowlisting %s from %s", type_name,
+ PROXY_MAP_PARAM_NAME(proxy_writer));
+ }
+ }
+}
+
+/* post_jail_init - initialization after privilege drop */
+
+static void post_jail_init(char *service_name, char **unused_argv)
+{
+ char *saved_filter;
+
+ /*
+ * Are we proxy writer?
+ */
+ if (strcmp(service_name, MAIL_SERVICE_PROXYWRITE) == 0)
+ proxy_writer = 1;
+ else if (strcmp(service_name, MAIL_SERVICE_PROXYMAP) != 0)
+ msg_fatal("service name must be one of %s or %s",
+ MAIL_SERVICE_PROXYMAP, MAIL_SERVICE_PROXYMAP);
+
+ /*
+ * Pre-allocate buffers.
+ */
+ request = vstring_alloc(10);
+ request_map = vstring_alloc(10);
+ request_key = vstring_alloc(10);
+ request_value = vstring_alloc(10);
+ map_type_name_flags = vstring_alloc(10);
+
+ /*
+ * Prepare the pre-approved list of proxied tables.
+ */
+ saved_filter = mystrdup(proxy_writer ? var_proxy_write_maps :
+ var_proxy_read_maps);
+ proxy_auth_maps = htable_create(13);
+ authorize_proxied_maps(saved_filter);
+ myfree(saved_filter);
+
+ /*
+ * Never, ever, get killed by a master signal, as that could corrupt a
+ * persistent database when we're in the middle of an update.
+ */
+ if (proxy_writer != 0)
+ setsid();
+}
+
+/* pre_accept - see if tables have changed */
+
+static void pre_accept(char *unused_name, char **unused_argv)
+{
+ const char *table;
+
+ if (proxy_writer == 0 && (table = dict_changed_name()) != 0) {
+ msg_info("table %s has changed -- restarting", table);
+ exit(0);
+ }
+}
+
+/* post_accept - announce our protocol name */
+
+static void post_accept(VSTREAM *stream, char *unused_name, char **unused_argv,
+ HTABLE *unused_attr)
+{
+
+ /*
+ * Announce the protocol.
+ */
+ attr_print(stream, ATTR_FLAG_NONE,
+ SEND_ATTR_STR(MAIL_ATTR_PROTO, MAIL_ATTR_PROTO_PROXYMAP),
+ ATTR_TYPE_END);
+ (void) vstream_fflush(stream);
+}
+
+MAIL_VERSION_STAMP_DECLARE;
+
+/* main - pass control to the multi-threaded skeleton */
+
+int main(int argc, char **argv)
+{
+ static const CONFIG_STR_TABLE str_table[] = {
+ VAR_ALIAS_MAPS, DEF_ALIAS_MAPS, &var_alias_maps, 0, 0,
+ VAR_LOCAL_RCPT_MAPS, DEF_LOCAL_RCPT_MAPS, &var_local_rcpt_maps, 0, 0,
+ VAR_VIRT_ALIAS_MAPS, DEF_VIRT_ALIAS_MAPS, &var_virt_alias_maps, 0, 0,
+ VAR_VIRT_ALIAS_DOMS, DEF_VIRT_ALIAS_DOMS, &var_virt_alias_doms, 0, 0,
+ VAR_VIRT_MAILBOX_MAPS, DEF_VIRT_MAILBOX_MAPS, &var_virt_mailbox_maps, 0, 0,
+ VAR_VIRT_MAILBOX_DOMS, DEF_VIRT_MAILBOX_DOMS, &var_virt_mailbox_doms, 0, 0,
+ VAR_RELAY_RCPT_MAPS, DEF_RELAY_RCPT_MAPS, &var_relay_rcpt_maps, 0, 0,
+ VAR_CANONICAL_MAPS, DEF_CANONICAL_MAPS, &var_canonical_maps, 0, 0,
+ VAR_SEND_CANON_MAPS, DEF_SEND_CANON_MAPS, &var_send_canon_maps, 0, 0,
+ VAR_RCPT_CANON_MAPS, DEF_RCPT_CANON_MAPS, &var_rcpt_canon_maps, 0, 0,
+ VAR_RELOCATED_MAPS, DEF_RELOCATED_MAPS, &var_relocated_maps, 0, 0,
+ VAR_TRANSPORT_MAPS, DEF_TRANSPORT_MAPS, &var_transport_maps, 0, 0,
+ VAR_VERIFY_MAP, DEF_VERIFY_MAP, &var_verify_map, 0, 0,
+ VAR_SMTPD_SND_AUTH_MAPS, DEF_SMTPD_SND_AUTH_MAPS, &var_smtpd_snd_auth_maps, 0, 0,
+ VAR_PSC_CACHE_MAP, DEF_PSC_CACHE_MAP, &var_psc_cache_map, 0, 0,
+ /* The following two must be last for $mapname to work as expected. */
+ VAR_PROXY_READ_MAPS, DEF_PROXY_READ_MAPS, &var_proxy_read_maps, 0, 0,
+ VAR_PROXY_WRITE_MAPS, DEF_PROXY_WRITE_MAPS, &var_proxy_write_maps, 0, 0,
+ 0,
+ };
+
+ /*
+ * Fingerprint executables and core dumps.
+ */
+ MAIL_VERSION_STAMP_ALLOCATE;
+
+ multi_server_main(argc, argv, proxymap_service,
+ CA_MAIL_SERVER_STR_TABLE(str_table),
+ CA_MAIL_SERVER_POST_INIT(post_jail_init),
+ CA_MAIL_SERVER_PRE_ACCEPT(pre_accept),
+ CA_MAIL_SERVER_POST_ACCEPT(post_accept),
+ /* XXX CA_MAIL_SERVER_SOLITARY if proxywrite */
+ 0);
+}