/*++ /* NAME /* lmtp_trouble 3 /* SUMMARY /* error handler policies /* SYNOPSIS /* #include "lmtp.h" /* /* int lmtp_site_fail(state, code, format, ...) /* LMTP_STATE *state; /* int code; /* char *format; /* /* int lmtp_mesg_fail(state, code, format, ...) /* LMTP_STATE *state; /* int code; /* char *format; /* /* void lmtp_rcpt_fail(state, code, recipient, format, ...) /* LMTP_STATE *state; /* int code; /* RECIPIENT *recipient; /* char *format; /* /* int lmtp_stream_except(state, exception, description) /* LMTP_STATE *state; /* int exception; /* char *description; /* DESCRIPTION /* This module handles all non-fatal errors that can happen while /* attempting to deliver mail via LMTP, and implements the policy /* of how to deal with the error. Depending on the nature of /* the problem, delivery of a single message is deferred, delivery /* of all messages to the same domain is deferred, or one or more /* recipients are given up as non-deliverable and a bounce log is /* updated. /* /* In addition, when an unexpected response code is seen such /* as 3xx where only 4xx or 5xx are expected, or any error code /* that suggests a syntax error or something similar, the /* protocol error flag is set so that the postmaster receives /* a transcript of the session. No notification is generated for /* what appear to be configuration errors - very likely, they /* would suffer the same problem and just cause more trouble. /* /* lmtp_site_fail() handles the case where the program fails to /* complete the initial LMTP handshake: the server is not reachable, /* is not running, does not want talk to us, or we talk to ourselves. /* The \fIcode\fR gives an error status code; the \fIformat\fR /* argument gives a textual description. The policy is: soft /* error: defer delivery of all messages to this domain; hard /* error: bounce all recipients of this message. /* The result is non-zero. /* /* lmtp_mesg_fail() handles the case where the lmtp server /* does not accept the sender address or the message data. /* The policy is: soft errors: defer delivery of this message; /* hard error: bounce all recipients of this message. /* The result is non-zero. /* /* lmtp_rcpt_fail() handles the case where a recipient is not /* accepted by the server for reasons other than that the server /* recipient limit is reached. The policy is: soft error: defer /* delivery to this recipient; hard error: bounce this recipient. /* /* lmtp_stream_except() handles the exceptions generated by /* the smtp_stream(3) module (i.e. timeouts and I/O errors). /* The \fIexception\fR argument specifies the type of problem. /* The \fIdescription\fR argument describes at what stage of /* the LMTP dialog the problem happened. The policy is to defer /* delivery of all messages to the same domain. The result is non-zero. /* DIAGNOSTICS /* Panic: unknown exception code. /* SEE ALSO /* lmtp_proto(3) lmtp high-level protocol /* smtp_stream(3) lmtp low-level protocol /* defer(3) basic message defer interface /* bounce(3) basic message bounce interface /* 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 /* /* Alterations for LMTP by: /* Philip A. Prindeville /* Mirapoint, Inc. /* USA. /* /* Additional work on LMTP by: /* Amos Gouaux /* University of Texas at Dallas /* P.O. Box 830688, MC34 /* Richardson, TX 75083, USA /*--*/ /* System library. */ #include <sys_defs.h> #include <stdlib.h> /* 44BSD stdarg.h uses abort() */ #include <stdarg.h> /* Utility library. */ #include <msg.h> #include <vstring.h> #include <stringops.h> #include <mymalloc.h> /* Global library. */ #include <smtp_stream.h> #include <deliver_request.h> #include <deliver_completed.h> #include <bounce.h> #include <defer.h> #include <mail_error.h> /* Application-specific. */ #include "lmtp.h" #define LMTP_SOFT(code) (((code) / 100) == 4) #define LMTP_HARD(code) (((code) / 100) == 5) /* lmtp_check_code - check response code */ static void lmtp_check_code(LMTP_STATE *state, int code) { /* * The intention of this stuff is to alert the postmaster when the local * Postfix LMTP client screws up, protocol wise. RFC 821 says that x0z * replies "refer to syntax errors, syntactically correct commands that * don't fit any functional category, and unimplemented or superfluous * commands". Unfortunately, this also triggers postmaster notices when * remote servers screw up, protocol wise. This is becoming a common * problem now that response codes are configured manually as part of * anti-UCE systems, by people who aren't aware of RFC details. */ if ((!LMTP_SOFT(code) && !LMTP_HARD(code)) || code == 555 /* RFC 1869, section 6.1. */ || (code >= 500 && code < 510)) state->error_mask |= MAIL_ERROR_PROTOCOL; } /* lmtp_site_fail - defer site or bounce recipients */ int lmtp_site_fail(LMTP_STATE *state, int code, char *format,...) { DELIVER_REQUEST *request = state->request; LMTP_SESSION *session = state->session; RECIPIENT *rcpt; int status; int nrcpt; int soft_error = LMTP_SOFT(code); va_list ap; VSTRING *why = vstring_alloc(100); /* * Initialize. */ va_start(ap, format); vstring_vsprintf(why, format, ap); va_end(ap); /* * If this is a soft error, postpone further deliveries to this domain. * Otherwise, generate a bounce record for each recipient. */ for (nrcpt = 0; nrcpt < request->rcpt_list.len; nrcpt++) { rcpt = request->rcpt_list.info + nrcpt; if (rcpt->offset == 0) continue; status = (soft_error ? defer_append : bounce_append) (DEL_REQ_TRACE_FLAGS(request->flags), request->queue_id, rcpt->orig_addr, rcpt->address, rcpt->offset, session ? session->namaddr : "none", request->arrival_time, "%s", vstring_str(why)); if (status == 0) { deliver_completed(state->src, rcpt->offset); rcpt->offset = 0; } state->status |= status; } if (soft_error && request->hop_status == 0) request->hop_status = mystrdup(vstring_str(why)); /* * Cleanup. */ vstring_free(why); return (-1); } /* lmtp_mesg_fail - defer message or bounce all recipients */ int lmtp_mesg_fail(LMTP_STATE *state, int code, char *format,...) { DELIVER_REQUEST *request = state->request; LMTP_SESSION *session = state->session; RECIPIENT *rcpt; int status; int nrcpt; va_list ap; VSTRING *why = vstring_alloc(100); /* * Initialize. */ va_start(ap, format); vstring_vsprintf(why, format, ap); va_end(ap); /* * If this is a soft error, postpone delivery of this message. Otherwise, * generate a bounce record for each recipient. */ for (nrcpt = 0; nrcpt < request->rcpt_list.len; nrcpt++) { rcpt = request->rcpt_list.info + nrcpt; if (rcpt->offset == 0) continue; status = (LMTP_SOFT(code) ? defer_append : bounce_append) (DEL_REQ_TRACE_FLAGS(request->flags), request->queue_id, rcpt->orig_addr, rcpt->address, rcpt->offset, session->namaddr, request->arrival_time, "%s", vstring_str(why)); if (status == 0) { deliver_completed(state->src, rcpt->offset); rcpt->offset = 0; } state->status |= status; } lmtp_check_code(state, code); /* * Cleanup. */ vstring_free(why); return (-1); } /* lmtp_rcpt_fail - defer or bounce recipient */ void lmtp_rcpt_fail(LMTP_STATE *state, int code, RECIPIENT *rcpt, char *format,...) { DELIVER_REQUEST *request = state->request; LMTP_SESSION *session = state->session; int status; va_list ap; /* * If this is a soft error, postpone delivery to this recipient. * Otherwise, generate a bounce record for this recipient. */ va_start(ap, format); status = (LMTP_SOFT(code) ? vdefer_append : vbounce_append) (DEL_REQ_TRACE_FLAGS(request->flags), request->queue_id, rcpt->orig_addr, rcpt->address, rcpt->offset, session->namaddr, request->arrival_time, format, ap); va_end(ap); if (status == 0) { deliver_completed(state->src, rcpt->offset); rcpt->offset = 0; } lmtp_check_code(state, code); state->status |= status; } /* lmtp_stream_except - defer domain after I/O problem */ int lmtp_stream_except(LMTP_STATE *state, int code, char *description) { DELIVER_REQUEST *request = state->request; LMTP_SESSION *session = state->session; RECIPIENT *rcpt; int nrcpt; VSTRING *why = vstring_alloc(100); /* * Initialize. */ switch (code) { default: msg_panic("lmtp_stream_except: unknown exception %d", code); case SMTP_ERR_EOF: vstring_sprintf(why, "lost connection with %s while %s", session->namaddr, description); break; case SMTP_ERR_TIME: vstring_sprintf(why, "conversation with %s timed out while %s", session->namaddr, description); break; } /* * At this point, the status of individual recipients remains unresolved. * All we know is that we should stay away from this host for a while. */ for (nrcpt = 0; nrcpt < request->rcpt_list.len; nrcpt++) { rcpt = request->rcpt_list.info + nrcpt; if (rcpt->offset == 0) continue; state->status |= defer_append(DEL_REQ_TRACE_FLAGS(request->flags), request->queue_id, rcpt->orig_addr, rcpt->address, rcpt->offset, session->namaddr, request->arrival_time, "%s", vstring_str(why)); } /* * Cleanup. */ vstring_free(why); return (-1); }