diff options
Diffstat (limited to '')
| -rw-r--r-- | src/smtp/smtp.h | 782 |
1 files changed, 782 insertions, 0 deletions
diff --git a/src/smtp/smtp.h b/src/smtp/smtp.h new file mode 100644 index 0000000..f8c8f58 --- /dev/null +++ b/src/smtp/smtp.h @@ -0,0 +1,782 @@ +/*++ +/* NAME +/* smtp 3h +/* SUMMARY +/* smtp client program +/* SYNOPSIS +/* #include "smtp.h" +/* DESCRIPTION +/* .nf + + /* + * System library. + */ +#include <string.h> + + /* + * Utility library. + */ +#include <vstream.h> +#include <vstring.h> +#include <argv.h> +#include <htable.h> +#include <dict.h> + + /* + * Global library. + */ +#include <deliver_request.h> +#include <scache.h> +#include <string_list.h> +#include <maps.h> +#include <tok822.h> +#include <dsn_buf.h> +#include <header_body_checks.h> + + /* + * Postfix TLS library. + */ +#include <tls.h> + + /* + * tlsproxy client. + */ +#include <tls_proxy.h> + + /* + * Global iterator support. This is updated by the connection-management + * loop, and contains dynamic context that appears in lookup keys for SASL + * passwords, TLS policy, cached SMTP connections, and cached TLS session + * keys. + * + * For consistency and maintainability, context that is used in more than one + * lookup key is formatted with smtp_key_format(). + */ +typedef struct SMTP_ITERATOR { + /* Public members. */ + VSTRING *request_nexthop; /* delivery request nexhop or empty */ + VSTRING *dest; /* current nexthop */ + VSTRING *host; /* hostname or empty */ + VSTRING *addr; /* printable address or empty */ + unsigned port; /* network byte order or null */ + struct DNS_RR *rr; /* DNS resource record or null */ + struct DNS_RR *mx; /* DNS resource record or null */ + /* Private members. */ + VSTRING *saved_dest; /* saved current nexthop */ + struct SMTP_STATE *parent; /* parent linkage */ +} SMTP_ITERATOR; + +#define SMTP_ITER_INIT(iter, _dest, _host, _addr, _port, state) do { \ + vstring_strcpy((iter)->dest, (_dest)); \ + vstring_strcpy((iter)->host, (_host)); \ + vstring_strcpy((iter)->addr, (_addr)); \ + (iter)->port = (_port); \ + (iter)->mx = (iter)->rr = 0; \ + vstring_strcpy((iter)->saved_dest, ""); \ + (iter)->parent = (state); \ + } while (0) + +#define SMTP_ITER_SAVE_DEST(iter) do { \ + vstring_strcpy((iter)->saved_dest, STR((iter)->dest)); \ + } while (0) + +#define SMTP_ITER_RESTORE_DEST(iter) do { \ + vstring_strcpy((iter)->dest, STR((iter)->saved_dest)); \ + } while (0) + +#define SMTP_ITER_UPDATE_HOST(iter, _host, _addr, _rr) do { \ + vstring_strcpy((iter)->host, (_host)); \ + vstring_strcpy((iter)->addr, (_addr)); \ + (iter)->rr = (_rr); \ + if ((_rr)->port) \ + (iter)->port = htons((_rr)->port); /* SRV port override */ \ + } while (0) + + /* + * TLS Policy support. + */ +#ifdef USE_TLS + +typedef struct SMTP_TLS_POLICY { + int level; /* TLS enforcement level */ + char *protocols; /* Acceptable SSL protocols */ + char *grade; /* Cipher grade: "export", ... */ + VSTRING *exclusions; /* Excluded SSL ciphers */ + ARGV *matchargv; /* Cert match patterns */ + DSN_BUF *why; /* Lookup error status */ + TLS_DANE *dane; /* DANE TLSA digests */ + char *sni; /* Optional SNI name when not DANE */ + int conn_reuse; /* enable connection reuse */ +} SMTP_TLS_POLICY; + + /* + * smtp_tls_policy.c + */ +extern void smtp_tls_list_init(void); +extern int smtp_tls_policy_cache_query(DSN_BUF *, SMTP_TLS_POLICY *, SMTP_ITERATOR *); +extern void smtp_tls_policy_cache_flush(void); + + /* + * Macros must use distinct names for local temporary variables, otherwise + * there will be bugs due to shadowing. This happened when an earlier + * version of smtp_tls_policy_dummy() invoked smtp_tls_policy_init(), but it + * could also happen without macro nesting. + * + * General principle: use all or part of the macro name in each temporary + * variable name. Then, append suffixes to the names if needed. + */ +#define smtp_tls_policy_dummy(t) do { \ + SMTP_TLS_POLICY *_tls_policy_dummy_tmp = (t); \ + smtp_tls_policy_init(_tls_policy_dummy_tmp, (DSN_BUF *) 0); \ + _tls_policy_dummy_tmp->level = TLS_LEV_NONE; \ + } while (0) + + /* This macro is not part of the module external interface. */ +#define smtp_tls_policy_init(t, w) do { \ + SMTP_TLS_POLICY *_tls_policy_init_tmp = (t); \ + _tls_policy_init_tmp->protocols = 0; \ + _tls_policy_init_tmp->grade = 0; \ + _tls_policy_init_tmp->exclusions = 0; \ + _tls_policy_init_tmp->matchargv = 0; \ + _tls_policy_init_tmp->why = (w); \ + _tls_policy_init_tmp->dane = 0; \ + _tls_policy_init_tmp->sni = 0; \ + _tls_policy_init_tmp->conn_reuse = 0; \ + } while (0) + +#endif + + /* + * State information associated with each SMTP delivery request. + * Session-specific state is stored separately. + */ +typedef struct SMTP_STATE { + int misc_flags; /* processing flags, see below */ + VSTREAM *src; /* queue file stream */ + const char *service; /* transport name */ + DELIVER_REQUEST *request; /* envelope info, offsets */ + struct SMTP_SESSION *session; /* network connection */ + int status; /* delivery status */ + ssize_t space_left; /* output length control */ + + /* + * Global iterator. + */ + SMTP_ITERATOR iterator[1]; /* Usage: state->iterator->member */ + + /* + * Global iterator. + */ +#ifdef USE_TLS + SMTP_TLS_POLICY tls[1]; /* Usage: state->tls->member */ +#endif + + /* + * Connection cache support. + */ + HTABLE *cache_used; /* cached addresses that were used */ + VSTRING *dest_label; /* cached logical/physical binding */ + VSTRING *dest_prop; /* binding properties, passivated */ + VSTRING *endp_label; /* cached session physical endpoint */ + VSTRING *endp_prop; /* endpoint properties, passivated */ + + /* + * Flags and counters to control the handling of mail delivery errors. + * There is some redundancy for sanity checking. At the end of an SMTP + * session all recipients should be marked one way or the other. + */ + int rcpt_left; /* recipients left over */ + int rcpt_drop; /* recipients marked as drop */ + int rcpt_keep; /* recipients marked as keep */ + + /* + * DSN Support introduced major bloat in error processing. + */ + DSN_BUF *why; /* on-the-fly formatting buffer */ + + /* + * Whether per-nexthop debug_peer support was requested. Otherwise, + * assume per-server debug_peer support. + */ + int debug_peer_per_nexthop; + + /* + * One-bit counters to avoid logging the same warning multiple times per + * delivery request. + */ + unsigned logged_line_length_limit:1; +} SMTP_STATE; + + /* + * Primitives to enable/disable/test connection caching and reuse based on + * the delivery request next-hop destination (i.e. not smtp_fallback_relay). + * + * Connection cache lookup by the delivery request next-hop destination allows + * a reuse request to skip over bad hosts, and may result in a connection to + * a fall-back relay. Once we have found a 'good' host for a delivery + * request next-hop, clear the delivery request next-hop destination, to + * avoid caching less-preferred connections under that same delivery request + * next-hop. + */ +#define SET_SCACHE_REQUEST_NEXTHOP(state, nexthop) do { \ + vstring_strcpy((state)->iterator->request_nexthop, nexthop); \ + } while (0) + +#define CLEAR_SCACHE_REQUEST_NEXTHOP(state) do { \ + STR((state)->iterator->request_nexthop)[0] = 0; \ + } while (0) + +#define HAVE_SCACHE_REQUEST_NEXTHOP(state) \ + (STR((state)->iterator->request_nexthop)[0] != 0) + + + /* + * Server features. + */ +#define SMTP_FEATURE_ESMTP (1<<0) +#define SMTP_FEATURE_8BITMIME (1<<1) +#define SMTP_FEATURE_PIPELINING (1<<2) +#define SMTP_FEATURE_SIZE (1<<3) +#define SMTP_FEATURE_STARTTLS (1<<4) +#define SMTP_FEATURE_AUTH (1<<5) +#define SMTP_FEATURE_XFORWARD_NAME (1<<7) +#define SMTP_FEATURE_XFORWARD_ADDR (1<<8) +#define SMTP_FEATURE_XFORWARD_PROTO (1<<9) +#define SMTP_FEATURE_XFORWARD_HELO (1<<10) +#define SMTP_FEATURE_XFORWARD_DOMAIN (1<<11) +#define SMTP_FEATURE_BEST_MX (1<<12) /* for next-hop or fall-back */ +#define SMTP_FEATURE_RSET_REJECTED (1<<13) /* RSET probe rejected */ +#define SMTP_FEATURE_FROM_CACHE (1<<14) /* cached connection */ +#define SMTP_FEATURE_DSN (1<<15) /* DSN supported */ +#define SMTP_FEATURE_PIX_NO_ESMTP (1<<16) /* PIX smtp fixup mode */ +#define SMTP_FEATURE_PIX_DELAY_DOTCRLF (1<<17) /* PIX smtp fixup mode */ +#define SMTP_FEATURE_XFORWARD_PORT (1<<18) +#define SMTP_FEATURE_EARLY_TLS_MAIL_REPLY (1<<19) /* CVE-2009-3555 */ +#define SMTP_FEATURE_XFORWARD_IDENT (1<<20) +#define SMTP_FEATURE_SMTPUTF8 (1<<21) /* RFC 6531 */ +#define SMTP_FEATURE_FROM_PROXY (1<<22) /* proxied connection */ + + /* + * Features that passivate under the endpoint. + */ +#define SMTP_FEATURE_ENDPOINT_MASK \ + (~(SMTP_FEATURE_BEST_MX | SMTP_FEATURE_RSET_REJECTED \ + | SMTP_FEATURE_FROM_CACHE)) + + /* + * Features that passivate under the logical destination. + */ +#define SMTP_FEATURE_DESTINATION_MASK (SMTP_FEATURE_BEST_MX) + + /* + * Misc flags. + */ +#define SMTP_MISC_FLAG_LOOP_DETECT (1<<0) +#define SMTP_MISC_FLAG_IN_STARTTLS (1<<1) +#define SMTP_MISC_FLAG_FIRST_NEXTHOP (1<<2) +#define SMTP_MISC_FLAG_FINAL_NEXTHOP (1<<3) +#define SMTP_MISC_FLAG_FINAL_SERVER (1<<4) +#define SMTP_MISC_FLAG_CONN_LOAD (1<<5) +#define SMTP_MISC_FLAG_CONN_STORE (1<<6) +#define SMTP_MISC_FLAG_COMPLETE_SESSION (1<<7) +#define SMTP_MISC_FLAG_PREF_IPV6 (1<<8) +#define SMTP_MISC_FLAG_PREF_IPV4 (1<<9) +#define SMTP_MISC_FLAG_FALLBACK_SRV_TO_MX (1<<10) + +#define SMTP_MISC_FLAG_CONN_CACHE_MASK \ + (SMTP_MISC_FLAG_CONN_LOAD | SMTP_MISC_FLAG_CONN_STORE) + + /* + * smtp.c + */ +#define SMTP_HAS_DSN(why) (STR((why)->status)[0] != 0) +#define SMTP_HAS_SOFT_DSN(why) (STR((why)->status)[0] == '4') +#define SMTP_HAS_HARD_DSN(why) (STR((why)->status)[0] == '5') +#define SMTP_HAS_LOOP_DSN(why) \ + (SMTP_HAS_DSN(why) && strcmp(STR((why)->status) + 1, ".4.6") == 0) + +#define SMTP_SET_SOFT_DSN(why) (STR((why)->status)[0] = '4') +#define SMTP_SET_HARD_DSN(why) (STR((why)->status)[0] = '5') + +extern int smtp_host_lookup_mask; /* host lookup methods to use */ + +#define SMTP_HOST_FLAG_DNS (1<<0) +#define SMTP_HOST_FLAG_NATIVE (1<<1) + +extern int smtp_dns_support; /* dns support level */ + +#define SMTP_DNS_INVALID (-1) /* smtp_dns_support_level = <bogus> */ +#define SMTP_DNS_DISABLED 0 /* smtp_dns_support_level = disabled */ +#define SMTP_DNS_ENABLED 1 /* smtp_dns_support_level = enabled */ +#define SMTP_DNS_DNSSEC 2 /* smtp_dns_support_level = dnssec */ + +extern SCACHE *smtp_scache; /* connection cache instance */ +extern STRING_LIST *smtp_cache_dest; /* cached destinations */ + +extern MAPS *smtp_ehlo_dis_maps; /* ehlo keyword filter */ + +extern MAPS *smtp_pix_bug_maps; /* PIX workarounds */ + +extern MAPS *smtp_generic_maps; /* make internal address valid */ +extern int smtp_ext_prop_mask; /* address extension propagation */ +extern unsigned smtp_dns_res_opt; /* DNS query flags */ + +extern STRING_LIST *smtp_use_srv_lookup;/* services with SRV record lookup */ + +#ifdef USE_TLS + +extern TLS_APPL_STATE *smtp_tls_ctx; /* client-side TLS engine */ +extern int smtp_tls_insecure_mx_policy; /* DANE post insecure MX? */ + +#endif + +extern HBC_CHECKS *smtp_header_checks; /* limited header checks */ +extern HBC_CHECKS *smtp_body_checks; /* limited body checks */ + + /* + * smtp_session.c + */ + +typedef struct SMTP_SESSION { + VSTREAM *stream; /* network connection */ + SMTP_ITERATOR *iterator; /* dest, host, addr, port */ + char *namaddr; /* mail exchanger */ + char *helo; /* helo response */ + unsigned port; /* network byte order */ + char *namaddrport; /* mail exchanger, incl. port */ + + VSTRING *buffer; /* I/O buffer */ + VSTRING *scratch; /* scratch buffer */ + VSTRING *scratch2; /* scratch buffer */ + + int features; /* server features */ + off_t size_limit; /* server limit or unknown */ + + ARGV *history; /* transaction log */ + int error_mask; /* error classes */ + struct MIME_STATE *mime_state; /* mime state machine */ + + int send_proto_helo; /* XFORWARD support */ + + time_t expire_time; /* session reuse expiration time */ + int reuse_count; /* # of times reused (for logging) */ + int forbidden; /* No further I/O allowed */ + +#ifdef USE_SASL_AUTH + char *sasl_mechanism_list; /* server mechanism list */ + char *sasl_username; /* client username */ + char *sasl_passwd; /* client password */ + struct XSASL_CLIENT *sasl_client; /* SASL internal state */ + VSTRING *sasl_reply; /* client response */ +#endif + + /* + * TLS related state, don't forget to initialize in session_tls_init()! + */ +#ifdef USE_TLS + TLS_SESS_STATE *tls_context; /* TLS library session state */ + char *tls_nexthop; /* Nexthop domain for cert checks */ + int tls_retry_plain; /* Try plain when TLS handshake fails */ +#endif + + SMTP_STATE *state; /* back link */ +} SMTP_SESSION; + +extern SMTP_SESSION *smtp_session_alloc(VSTREAM *, SMTP_ITERATOR *, time_t, int); +extern void smtp_session_new_stream(SMTP_SESSION *, VSTREAM *, time_t, int); +extern int smtp_sess_plaintext_ok(SMTP_ITERATOR *, int); +extern void smtp_session_free(SMTP_SESSION *); +extern int smtp_session_passivate(SMTP_SESSION *, VSTRING *, VSTRING *); +extern SMTP_SESSION *smtp_session_activate(int, SMTP_ITERATOR *, VSTRING *, VSTRING *); + + /* + * What's in a name? + */ +#define SMTP_HNAME(rr) (var_smtp_cname_overr ? (rr)->rname : (rr)->qname) + + /* + * smtp_connect.c + */ +extern int smtp_connect(SMTP_STATE *); + + /* + * smtp_proto.c + */ +extern void smtp_vrfy_init(void); +extern int smtp_helo(SMTP_STATE *); +extern int smtp_xfer(SMTP_STATE *); +extern int smtp_rset(SMTP_STATE *); +extern int smtp_quit(SMTP_STATE *); + +extern HBC_CALL_BACKS smtp_hbc_callbacks[]; + + /* + * A connection is re-usable if session->expire_time is > 0 and the + * expiration time has not been reached. This is subtle because the timer + * can expire between sending a command and receiving the reply for that + * command. + * + * But wait, there is more! When SMTP command pipelining is enabled, there are + * two protocol loops that execute at very different times: one loop that + * generates commands, and one loop that receives replies to those commands. + * These will be called "sender loop" and "receiver loop", respectively. At + * well-defined protocol synchronization points, the sender loop pauses to + * let the receiver loop catch up. + * + * When we choose to reuse a connection, both the sender and receiver protocol + * loops end with "." (mail delivery) or "RSET" (address probe). When we + * choose not to reuse, both the sender and receiver protocol loops end with + * "QUIT". The problem is that we must make the same protocol choices in + * both the sender and receiver loops, even though those loops may execute + * at completely different times. + * + * We "freeze" the choice in the sender loop, just before we generate "." or + * "RSET". The reader loop leaves the connection cacheable even if the timer + * expires by the time the response arrives. The connection cleanup code + * will call smtp_quit() for connections with an expired cache expiration + * timer. + * + * We could have made the programmer's life a lot simpler by not making a + * choice at all, and always leaving it up to the connection cleanup code to + * call smtp_quit() for connections with an expired cache expiration timer. + * + * As a general principle, neither the sender loop nor the receiver loop must + * modify the connection caching state, if that can affect the receiver + * state machine for not-yet processed replies to already-generated + * commands. This restriction does not apply when we have to exit the + * protocol loops prematurely due to e.g., timeout or connection loss, so + * that those pending replies will never be received. + * + * But wait, there is even more! Only the first good connection for a specific + * destination may be cached under both the next-hop destination name and + * the server address; connections to alternate servers must be cached under + * the server address alone. This means we must distinguish between bad + * connections and other reasons why connections cannot be cached. + */ +#define THIS_SESSION_IS_CACHED \ + (!THIS_SESSION_IS_FORBIDDEN && session->expire_time > 0) + +#define THIS_SESSION_IS_EXPIRED \ + (THIS_SESSION_IS_CACHED \ + && (session->expire_time < vstream_ftime(session->stream) \ + || (var_smtp_reuse_count > 0 \ + && session->reuse_count >= var_smtp_reuse_count))) + +#define THIS_SESSION_IS_THROTTLED \ + (!THIS_SESSION_IS_FORBIDDEN && session->expire_time < 0) + +#define THIS_SESSION_IS_FORBIDDEN \ + (session->forbidden != 0) + + /* Bring the bad news. */ + +#define DONT_CACHE_THIS_SESSION \ + (session->expire_time = 0) + +#define DONT_CACHE_THROTTLED_SESSION \ + (session->expire_time = -1) + +#define DONT_USE_FORBIDDEN_SESSION \ + (session->forbidden = 1) + + /* Initialization. */ + +#define USE_NEWBORN_SESSION \ + (session->forbidden = 0) + +#define CACHE_THIS_SESSION_UNTIL(when) \ + (session->expire_time = (when)) + + /* + * Encapsulate the following so that we don't expose details of + * connection management and error handling to the SMTP protocol engine. + */ +#ifdef USE_SASL_AUTH +#define HAVE_SASL_CREDENTIALS \ + (var_smtp_sasl_enable \ + && *var_smtp_sasl_passwd \ + && smtp_sasl_passwd_lookup(session)) +#else +#define HAVE_SASL_CREDENTIALS (0) +#endif + +#define PREACTIVE_DELAY \ + (session->state->request->msg_stats.active_arrival.tv_sec - \ + session->state->request->msg_stats.incoming_arrival.tv_sec) + +#define TRACE_REQ_ONLY (DEL_REQ_TRACE_ONLY(state->request->flags)) + +#define PLAINTEXT_FALLBACK_OK_AFTER_STARTTLS_FAILURE \ + (session->tls_context == 0 \ + && state->tls->level == TLS_LEV_MAY \ + && (TRACE_REQ_ONLY || PREACTIVE_DELAY >= var_min_backoff_time) \ + && !HAVE_SASL_CREDENTIALS) + +#define PLAINTEXT_FALLBACK_OK_AFTER_TLS_SESSION_FAILURE \ + (session->tls_context != 0 \ + && SMTP_RCPT_LEFT(state) > SMTP_RCPT_MARK_COUNT(state) \ + && state->tls->level == TLS_LEV_MAY \ + && (TRACE_REQ_ONLY || PREACTIVE_DELAY >= var_min_backoff_time) \ + && !HAVE_SASL_CREDENTIALS) + + /* + * XXX The following will not retry recipients that were deferred while the + * SMTP_MISC_FLAG_FINAL_SERVER flag was already set. This includes the case + * when TLS fails in the middle of a delivery. + */ +#define RETRY_AS_PLAINTEXT do { \ + session->tls_retry_plain = 1; \ + state->misc_flags &= ~SMTP_MISC_FLAG_FINAL_SERVER; \ + } while (0) + + /* + * smtp_chat.c + */ +typedef struct SMTP_RESP { /* server response */ + int code; /* SMTP code */ + const char *dsn; /* enhanced status */ + char *str; /* full reply */ + VSTRING *dsn_buf; /* status buffer */ + VSTRING *str_buf; /* reply buffer */ +} SMTP_RESP; + +extern void PRINTFLIKE(2, 3) smtp_chat_cmd(SMTP_SESSION *, const char *,...); +extern DICT *smtp_chat_resp_filter; +extern SMTP_RESP *smtp_chat_resp(SMTP_SESSION *); +extern void smtp_chat_init(SMTP_SESSION *); +extern void smtp_chat_reset(SMTP_SESSION *); +extern void smtp_chat_notify(SMTP_SESSION *); + +#define SMTP_RESP_FAKE(resp, _dsn) \ + ((resp)->code = 0, \ + (resp)->dsn = (_dsn), \ + (resp)->str = DSN_BY_LOCAL_MTA, \ + (resp)) + +#define DSN_BY_LOCAL_MTA ((char *) 0) /* DSN issued by local MTA */ + +#define SMTP_RESP_SET_DSN(resp, _dsn) do { \ + vstring_strcpy((resp)->dsn_buf, (_dsn)); \ + (resp)->dsn = STR((resp)->dsn_buf); \ + } while (0) + + /* + * These operations implement a redundant mark-and-sweep algorithm that + * explicitly accounts for the fate of every recipient. The interface is + * documented in smtp_rcpt.c, which also implements the sweeping. The + * smtp_trouble.c module does most of the marking after failure. + * + * When a delivery fails or succeeds, take one of the following actions: + * + * - Mark the recipient as KEEP (deliver to alternate MTA) and do not update + * the delivery request status. + * + * - Mark the recipient as DROP (remove from delivery request), log whether + * delivery succeeded or failed, delete the recipient from the queue file + * and/or update defer or bounce logfiles, and update the delivery request + * status. + * + * At the end of a delivery attempt, all recipients must be marked one way or + * the other. Failure to do so will trigger a panic. + */ +#define SMTP_RCPT_STATE_KEEP 1 /* send to backup host */ +#define SMTP_RCPT_STATE_DROP 2 /* remove from request */ +#define SMTP_RCPT_INIT(state) do { \ + (state)->rcpt_drop = (state)->rcpt_keep = 0; \ + (state)->rcpt_left = state->request->rcpt_list.len; \ + } while (0) + +#define SMTP_RCPT_DROP(state, rcpt) do { \ + (rcpt)->u.status = SMTP_RCPT_STATE_DROP; (state)->rcpt_drop++; \ + } while (0) + +#define SMTP_RCPT_KEEP(state, rcpt) do { \ + (rcpt)->u.status = SMTP_RCPT_STATE_KEEP; (state)->rcpt_keep++; \ + } while (0) + +#define SMTP_RCPT_ISMARKED(rcpt) ((rcpt)->u.status != 0) + +#define SMTP_RCPT_LEFT(state) (state)->rcpt_left + +#define SMTP_RCPT_MARK_COUNT(state) ((state)->rcpt_drop + (state)->rcpt_keep) + +extern void smtp_rcpt_cleanup(SMTP_STATE *); +extern void smtp_rcpt_done(SMTP_STATE *, SMTP_RESP *, RECIPIENT *); + + /* + * smtp_trouble.c + */ +#define SMTP_THROTTLE 1 +#define SMTP_NOTHROTTLE 0 +extern int smtp_sess_fail(SMTP_STATE *); +extern int PRINTFLIKE(5, 6) smtp_misc_fail(SMTP_STATE *, int, const char *, + SMTP_RESP *, const char *,...); +extern void PRINTFLIKE(5, 6) smtp_rcpt_fail(SMTP_STATE *, RECIPIENT *, + const char *, SMTP_RESP *, + const char *,...); +extern int smtp_stream_except(SMTP_STATE *, int, const char *); + +#define smtp_site_fail(state, mta, resp, ...) \ + smtp_misc_fail((state), SMTP_THROTTLE, (mta), (resp), __VA_ARGS__) +#define smtp_mesg_fail(state, mta, resp, ...) \ + smtp_misc_fail((state), SMTP_NOTHROTTLE, (mta), (resp), __VA_ARGS__) + + /* + * smtp_unalias.c + */ +extern const char *smtp_unalias_name(const char *); +extern VSTRING *smtp_unalias_addr(VSTRING *, const char *); + + /* + * smtp_state.c + */ +extern SMTP_STATE *smtp_state_alloc(void); +extern void smtp_state_free(SMTP_STATE *); + + /* + * smtp_map11.c + */ +extern int smtp_map11_external(VSTRING *, MAPS *, int); +extern int smtp_map11_tree(TOK822 *, MAPS *, int); +extern int smtp_map11_internal(VSTRING *, MAPS *, int); + + /* + * smtp_key.c + */ +char *smtp_key_prefix(VSTRING *, const char *, SMTP_ITERATOR *, int); + +#define SMTP_KEY_FLAG_SERVICE (1<<0) /* service name */ +#define SMTP_KEY_FLAG_SENDER (1<<1) /* sender address */ +#define SMTP_KEY_FLAG_REQ_NEXTHOP (1<<2) /* delivery request nexthop */ +#define SMTP_KEY_FLAG_CUR_NEXTHOP (1<<3) /* current nexthop */ +#define SMTP_KEY_FLAG_HOSTNAME (1<<4) /* remote host name */ +#define SMTP_KEY_FLAG_ADDR (1<<5) /* remote address */ +#define SMTP_KEY_FLAG_PORT (1<<6) /* remote port */ +#define SMTP_KEY_FLAG_TLS_LEVEL (1<<7) /* requested TLS level */ + +#define SMTP_KEY_MASK_ALL \ + (SMTP_KEY_FLAG_SERVICE | SMTP_KEY_FLAG_SENDER | \ + SMTP_KEY_FLAG_REQ_NEXTHOP | \ + SMTP_KEY_FLAG_CUR_NEXTHOP | SMTP_KEY_FLAG_HOSTNAME | \ + SMTP_KEY_FLAG_ADDR | SMTP_KEY_FLAG_PORT | SMTP_KEY_FLAG_TLS_LEVEL) + + /* + * Conditional lookup-key flags for cached connections that may be + * SASL-authenticated with a per-{sender, nexthop, or hostname} credential. + * Each bit corresponds to one type of smtp_sasl_password_file lookup key, + * and is turned on only when the corresponding main.cf parameter is turned + * on. + */ +#define COND_SASL_SMTP_KEY_FLAG_SENDER \ + ((var_smtp_sender_auth && *var_smtp_sasl_passwd) ? \ + SMTP_KEY_FLAG_SENDER : 0) + +#define COND_SASL_SMTP_KEY_FLAG_CUR_NEXTHOP \ + (*var_smtp_sasl_passwd ? SMTP_KEY_FLAG_CUR_NEXTHOP : 0) + +#ifdef USE_TLS +#define COND_TLS_SMTP_KEY_FLAG_CUR_NEXTHOP \ + (TLS_MUST_MATCH(state->tls->level) ? SMTP_KEY_FLAG_CUR_NEXTHOP : 0) +#else +#define COND_TLS_SMTP_KEY_FLAG_CUR_NEXTHOP \ + (0) +#endif + +#define COND_SASL_SMTP_KEY_FLAG_HOSTNAME \ + (*var_smtp_sasl_passwd ? SMTP_KEY_FLAG_HOSTNAME : 0) + + /* + * Connection-cache destination lookup key, based on the delivery request + * nexthop. The SENDER attribute is a proxy for sender-dependent SASL + * credentials (or absence thereof), and prevents false connection sharing + * when different SASL credentials may be required for different deliveries + * to the same domain and port. Likewise, the delivery request nexthop + * (REQ_NEXTHOP) prevents false sharing of TLS identities (the destination + * key links only to appropriate endpoint lookup keys). The SERVICE + * attribute is a proxy for all request-independent configuration details. + */ +#define SMTP_KEY_MASK_SCACHE_DEST_LABEL \ + (SMTP_KEY_FLAG_SERVICE | COND_SASL_SMTP_KEY_FLAG_SENDER \ + | SMTP_KEY_FLAG_REQ_NEXTHOP) + + /* + * Connection-cache endpoint lookup key. The SENDER, CUR_NEXTHOP, HOSTNAME, + * PORT and TLS_LEVEL attributes are proxies for SASL credentials and TLS + * authentication (or absence thereof), and prevent false connection sharing + * when different SASL credentials or TLS identities may be required for + * different deliveries to the same IP address and port. The SERVICE + * attribute is a proxy for all request-independent configuration details. + */ +#define SMTP_KEY_MASK_SCACHE_ENDP_LABEL \ + (SMTP_KEY_FLAG_SERVICE | COND_SASL_SMTP_KEY_FLAG_SENDER \ + | COND_SASL_SMTP_KEY_FLAG_CUR_NEXTHOP \ + | COND_SASL_SMTP_KEY_FLAG_HOSTNAME \ + | COND_TLS_SMTP_KEY_FLAG_CUR_NEXTHOP | SMTP_KEY_FLAG_ADDR | \ + SMTP_KEY_FLAG_PORT | SMTP_KEY_FLAG_TLS_LEVEL) + + /* + * Silly little macros. + */ +#define STR(s) vstring_str(s) +#define LEN(s) VSTRING_LEN(s) + +extern int smtp_mode; + +#define VAR_LMTP_SMTP(x) (smtp_mode ? VAR_SMTP_##x : VAR_LMTP_##x) +#define LMTP_SMTP_SUFFIX(x) (smtp_mode ? x##_SMTP : x##_LMTP) + + /* + * Parsed command-line attributes. These do not change during the process + * lifetime. + */ +typedef struct { + int flags; /* from flags=, see below */ +} SMTP_CLI_ATTR; + +#define SMTP_CLI_FLAG_DELIVERED_TO (1<<0) /* prepend Delivered-To: */ +#define SMTP_CLI_FLAG_ORIG_RCPT (1<<1) /* prepend X-Original-To: */ +#define SMTP_CLI_FLAG_RETURN_PATH (1<<2) /* prepend Return-Path: */ +#define SMTP_CLI_FLAG_FINAL_DELIVERY (1<<3) /* final, not relay */ + +#define SMTP_CLI_MASK_ADD_HEADERS (SMTP_CLI_FLAG_DELIVERED_TO | \ + SMTP_CLI_FLAG_ORIG_RCPT | SMTP_CLI_FLAG_RETURN_PATH) + +extern SMTP_CLI_ATTR smtp_cli_attr; + + /* + * smtp_misc.c. + */ +extern void smtp_rewrite_generic_internal(VSTRING *, const char *); +extern void smtp_quote_822_address_flags(VSTRING *, const char *, int); +extern void smtp_quote_821_address(VSTRING *, const char *); + + /* + * header_from_format support, for postmaster notifications. + */ +extern int smtp_hfrom_format; + +/* LICENSE +/* .ad +/* .fi +/* The Secure Mailer license must be distributed with this software. +/* 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 +/* +/* TLS support originally by: +/* Lutz Jaenicke +/* BTU Cottbus +/* Allgemeine Elektrotechnik +/* Universitaetsplatz 3-4 +/* D-03044 Cottbus, Germany +/* +/* Victor Duchovni +/* Morgan Stanley +/*--*/ |