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diff --git a/src/acl.c b/src/acl.c
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+++ b/src/acl.c
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+/*************************************************
+* Exim - an Internet mail transport agent *
+*************************************************/
+
+/* Copyright (c) University of Cambridge 1995 - 2018 */
+/* Copyright (c) The Exim Maintainers 2020 */
+/* See the file NOTICE for conditions of use and distribution. */
+
+/* Code for handling Access Control Lists (ACLs) */
+
+#include "exim.h"
+
+
+/* Default callout timeout */
+
+#define CALLOUT_TIMEOUT_DEFAULT 30
+
+/* ACL verb codes - keep in step with the table of verbs that follows */
+
+enum { ACL_ACCEPT, ACL_DEFER, ACL_DENY, ACL_DISCARD, ACL_DROP, ACL_REQUIRE,
+ ACL_WARN };
+
+/* ACL verbs */
+
+static uschar *verbs[] = {
+ [ACL_ACCEPT] = US"accept",
+ [ACL_DEFER] = US"defer",
+ [ACL_DENY] = US"deny",
+ [ACL_DISCARD] = US"discard",
+ [ACL_DROP] = US"drop",
+ [ACL_REQUIRE] = US"require",
+ [ACL_WARN] = US"warn"
+};
+
+/* For each verb, the conditions for which "message" or "log_message" are used
+are held as a bitmap. This is to avoid expanding the strings unnecessarily. For
+"accept", the FAIL case is used only after "endpass", but that is selected in
+the code. */
+
+static int msgcond[] = {
+ [ACL_ACCEPT] = BIT(OK) | BIT(FAIL) | BIT(FAIL_DROP),
+ [ACL_DEFER] = BIT(OK),
+ [ACL_DENY] = BIT(OK),
+ [ACL_DISCARD] = BIT(OK) | BIT(FAIL) | BIT(FAIL_DROP),
+ [ACL_DROP] = BIT(OK),
+ [ACL_REQUIRE] = BIT(FAIL) | BIT(FAIL_DROP),
+ [ACL_WARN] = BIT(OK)
+ };
+
+/* ACL condition and modifier codes - keep in step with the table that
+follows.
+down. */
+
+enum { ACLC_ACL,
+ ACLC_ADD_HEADER,
+ ACLC_AUTHENTICATED,
+#ifdef EXPERIMENTAL_BRIGHTMAIL
+ ACLC_BMI_OPTIN,
+#endif
+ ACLC_CONDITION,
+ ACLC_CONTINUE,
+ ACLC_CONTROL,
+#ifdef EXPERIMENTAL_DCC
+ ACLC_DCC,
+#endif
+#ifdef WITH_CONTENT_SCAN
+ ACLC_DECODE,
+#endif
+ ACLC_DELAY,
+#ifndef DISABLE_DKIM
+ ACLC_DKIM_SIGNER,
+ ACLC_DKIM_STATUS,
+#endif
+#ifdef SUPPORT_DMARC
+ ACLC_DMARC_STATUS,
+#endif
+ ACLC_DNSLISTS,
+ ACLC_DOMAINS,
+ ACLC_ENCRYPTED,
+ ACLC_ENDPASS,
+ ACLC_HOSTS,
+ ACLC_LOCAL_PARTS,
+ ACLC_LOG_MESSAGE,
+ ACLC_LOG_REJECT_TARGET,
+ ACLC_LOGWRITE,
+#ifdef WITH_CONTENT_SCAN
+ ACLC_MALWARE,
+#endif
+ ACLC_MESSAGE,
+#ifdef WITH_CONTENT_SCAN
+ ACLC_MIME_REGEX,
+#endif
+ ACLC_QUEUE,
+ ACLC_RATELIMIT,
+ ACLC_RECIPIENTS,
+#ifdef WITH_CONTENT_SCAN
+ ACLC_REGEX,
+#endif
+ ACLC_REMOVE_HEADER,
+ ACLC_SENDER_DOMAINS,
+ ACLC_SENDERS,
+ ACLC_SET,
+#ifdef WITH_CONTENT_SCAN
+ ACLC_SPAM,
+#endif
+#ifdef SUPPORT_SPF
+ ACLC_SPF,
+ ACLC_SPF_GUESS,
+#endif
+ ACLC_UDPSEND,
+ ACLC_VERIFY };
+
+/* ACL conditions/modifiers: "delay", "control", "continue", "endpass",
+"message", "log_message", "log_reject_target", "logwrite", "queue" and "set" are
+modifiers that look like conditions but always return TRUE. They are used for
+their side effects. Do not invent new modifier names that result in one name
+being the prefix of another; the binary-search in the list will go wrong. */
+
+typedef struct condition_def {
+ uschar *name;
+
+/* Flag to indicate the condition/modifier has a string expansion done
+at the outer level. In the other cases, expansion already occurs in the
+checking functions. */
+ BOOL expand_at_top:1;
+
+ BOOL is_modifier:1;
+
+/* Bit map vector of which conditions and modifiers are not allowed at certain
+times. For each condition and modifier, there's a bitmap of dis-allowed times.
+For some, it is easier to specify the negation of a small number of allowed
+times. */
+ unsigned forbids;
+
+} condition_def;
+
+static condition_def conditions[] = {
+ [ACLC_ACL] = { US"acl", FALSE, FALSE, 0 },
+
+ [ACLC_ADD_HEADER] = { US"add_header", TRUE, TRUE,
+ (unsigned int)
+ ~(ACL_BIT_MAIL | ACL_BIT_RCPT |
+ ACL_BIT_PREDATA | ACL_BIT_DATA |
+#ifndef DISABLE_PRDR
+ ACL_BIT_PRDR |
+#endif
+ ACL_BIT_MIME | ACL_BIT_NOTSMTP |
+ ACL_BIT_DKIM |
+ ACL_BIT_NOTSMTP_START),
+ },
+
+ [ACLC_AUTHENTICATED] = { US"authenticated", FALSE, FALSE,
+ ACL_BIT_NOTSMTP | ACL_BIT_NOTSMTP_START |
+ ACL_BIT_CONNECT | ACL_BIT_HELO,
+ },
+#ifdef EXPERIMENTAL_BRIGHTMAIL
+ [ACLC_BMI_OPTIN] = { US"bmi_optin", TRUE, TRUE,
+ ACL_BIT_AUTH |
+ ACL_BIT_CONNECT | ACL_BIT_HELO |
+ ACL_BIT_DATA | ACL_BIT_MIME |
+# ifndef DISABLE_PRDR
+ ACL_BIT_PRDR |
+# endif
+ ACL_BIT_ETRN | ACL_BIT_EXPN |
+ ACL_BIT_MAILAUTH |
+ ACL_BIT_MAIL | ACL_BIT_STARTTLS |
+ ACL_BIT_VRFY | ACL_BIT_PREDATA |
+ ACL_BIT_NOTSMTP_START,
+ },
+#endif
+ [ACLC_CONDITION] = { US"condition", TRUE, FALSE, 0 },
+ [ACLC_CONTINUE] = { US"continue", TRUE, TRUE, 0 },
+
+ /* Certain types of control are always allowed, so we let it through
+ always and check in the control processing itself. */
+ [ACLC_CONTROL] = { US"control", TRUE, TRUE, 0 },
+
+#ifdef EXPERIMENTAL_DCC
+ [ACLC_DCC] = { US"dcc", TRUE, FALSE,
+ (unsigned int)
+ ~(ACL_BIT_DATA |
+# ifndef DISABLE_PRDR
+ ACL_BIT_PRDR |
+# endif
+ ACL_BIT_NOTSMTP),
+ },
+#endif
+#ifdef WITH_CONTENT_SCAN
+ [ACLC_DECODE] = { US"decode", TRUE, FALSE, (unsigned int) ~ACL_BIT_MIME },
+
+#endif
+ [ACLC_DELAY] = { US"delay", TRUE, TRUE, ACL_BIT_NOTQUIT },
+#ifndef DISABLE_DKIM
+ [ACLC_DKIM_SIGNER] = { US"dkim_signers", TRUE, FALSE, (unsigned int) ~ACL_BIT_DKIM },
+ [ACLC_DKIM_STATUS] = { US"dkim_status", TRUE, FALSE, (unsigned int) ~ACL_BIT_DKIM },
+#endif
+#ifdef SUPPORT_DMARC
+ [ACLC_DMARC_STATUS] = { US"dmarc_status", TRUE, FALSE, (unsigned int) ~ACL_BIT_DATA },
+#endif
+
+ /* Explicit key lookups can be made in non-smtp ACLs so pass
+ always and check in the verify processing itself. */
+ [ACLC_DNSLISTS] = { US"dnslists", TRUE, FALSE, 0 },
+
+ [ACLC_DOMAINS] = { US"domains", FALSE, FALSE,
+ (unsigned int)
+ ~(ACL_BIT_RCPT | ACL_BIT_VRFY
+#ifndef DISABLE_PRDR
+ |ACL_BIT_PRDR
+#endif
+ ),
+ },
+ [ACLC_ENCRYPTED] = { US"encrypted", FALSE, FALSE,
+ ACL_BIT_NOTSMTP | ACL_BIT_NOTSMTP_START |
+ ACL_BIT_HELO,
+ },
+
+ [ACLC_ENDPASS] = { US"endpass", TRUE, TRUE, 0 },
+
+ [ACLC_HOSTS] = { US"hosts", FALSE, FALSE,
+ ACL_BIT_NOTSMTP | ACL_BIT_NOTSMTP_START,
+ },
+ [ACLC_LOCAL_PARTS] = { US"local_parts", FALSE, FALSE,
+ (unsigned int)
+ ~(ACL_BIT_RCPT | ACL_BIT_VRFY
+#ifndef DISABLE_PRDR
+ | ACL_BIT_PRDR
+#endif
+ ),
+ },
+
+ [ACLC_LOG_MESSAGE] = { US"log_message", TRUE, TRUE, 0 },
+ [ACLC_LOG_REJECT_TARGET] = { US"log_reject_target", TRUE, TRUE, 0 },
+ [ACLC_LOGWRITE] = { US"logwrite", TRUE, TRUE, 0 },
+
+#ifdef WITH_CONTENT_SCAN
+ [ACLC_MALWARE] = { US"malware", TRUE, FALSE,
+ (unsigned int)
+ ~(ACL_BIT_DATA |
+# ifndef DISABLE_PRDR
+ ACL_BIT_PRDR |
+# endif
+ ACL_BIT_NOTSMTP),
+ },
+#endif
+
+ [ACLC_MESSAGE] = { US"message", TRUE, TRUE, 0 },
+#ifdef WITH_CONTENT_SCAN
+ [ACLC_MIME_REGEX] = { US"mime_regex", TRUE, FALSE, (unsigned int) ~ACL_BIT_MIME },
+#endif
+
+ [ACLC_QUEUE] = { US"queue", TRUE, TRUE,
+ ACL_BIT_NOTSMTP |
+#ifndef DISABLE_PRDR
+ ACL_BIT_PRDR |
+#endif
+ ACL_BIT_DATA,
+ },
+
+ [ACLC_RATELIMIT] = { US"ratelimit", TRUE, FALSE, 0 },
+ [ACLC_RECIPIENTS] = { US"recipients", FALSE, FALSE, (unsigned int) ~ACL_BIT_RCPT },
+
+#ifdef WITH_CONTENT_SCAN
+ [ACLC_REGEX] = { US"regex", TRUE, FALSE,
+ (unsigned int)
+ ~(ACL_BIT_DATA |
+# ifndef DISABLE_PRDR
+ ACL_BIT_PRDR |
+# endif
+ ACL_BIT_NOTSMTP |
+ ACL_BIT_MIME),
+ },
+
+#endif
+ [ACLC_REMOVE_HEADER] = { US"remove_header", TRUE, TRUE,
+ (unsigned int)
+ ~(ACL_BIT_MAIL|ACL_BIT_RCPT |
+ ACL_BIT_PREDATA | ACL_BIT_DATA |
+#ifndef DISABLE_PRDR
+ ACL_BIT_PRDR |
+#endif
+ ACL_BIT_MIME | ACL_BIT_NOTSMTP |
+ ACL_BIT_NOTSMTP_START),
+ },
+ [ACLC_SENDER_DOMAINS] = { US"sender_domains", FALSE, FALSE,
+ ACL_BIT_AUTH | ACL_BIT_CONNECT |
+ ACL_BIT_HELO |
+ ACL_BIT_MAILAUTH | ACL_BIT_QUIT |
+ ACL_BIT_ETRN | ACL_BIT_EXPN |
+ ACL_BIT_STARTTLS | ACL_BIT_VRFY,
+ },
+ [ACLC_SENDERS] = { US"senders", FALSE, FALSE,
+ ACL_BIT_AUTH | ACL_BIT_CONNECT |
+ ACL_BIT_HELO |
+ ACL_BIT_MAILAUTH | ACL_BIT_QUIT |
+ ACL_BIT_ETRN | ACL_BIT_EXPN |
+ ACL_BIT_STARTTLS | ACL_BIT_VRFY,
+ },
+
+ [ACLC_SET] = { US"set", TRUE, TRUE, 0 },
+
+#ifdef WITH_CONTENT_SCAN
+ [ACLC_SPAM] = { US"spam", TRUE, FALSE,
+ (unsigned int) ~(ACL_BIT_DATA |
+# ifndef DISABLE_PRDR
+ ACL_BIT_PRDR |
+# endif
+ ACL_BIT_NOTSMTP),
+ },
+#endif
+#ifdef SUPPORT_SPF
+ [ACLC_SPF] = { US"spf", TRUE, FALSE,
+ ACL_BIT_AUTH | ACL_BIT_CONNECT |
+ ACL_BIT_HELO | ACL_BIT_MAILAUTH |
+ ACL_BIT_ETRN | ACL_BIT_EXPN |
+ ACL_BIT_STARTTLS | ACL_BIT_VRFY |
+ ACL_BIT_NOTSMTP | ACL_BIT_NOTSMTP_START,
+ },
+ [ACLC_SPF_GUESS] = { US"spf_guess", TRUE, FALSE,
+ ACL_BIT_AUTH | ACL_BIT_CONNECT |
+ ACL_BIT_HELO | ACL_BIT_MAILAUTH |
+ ACL_BIT_ETRN | ACL_BIT_EXPN |
+ ACL_BIT_STARTTLS | ACL_BIT_VRFY |
+ ACL_BIT_NOTSMTP | ACL_BIT_NOTSMTP_START,
+ },
+#endif
+ [ACLC_UDPSEND] = { US"udpsend", TRUE, TRUE, 0 },
+
+ /* Certain types of verify are always allowed, so we let it through
+ always and check in the verify function itself */
+ [ACLC_VERIFY] = { US"verify", TRUE, FALSE, 0 },
+};
+
+
+
+/* Return values from decode_control(); used as index so keep in step
+with the controls_list table that follows! */
+
+enum {
+ CONTROL_AUTH_UNADVERTISED,
+#ifdef EXPERIMENTAL_BRIGHTMAIL
+ CONTROL_BMI_RUN,
+#endif
+ CONTROL_CASEFUL_LOCAL_PART,
+ CONTROL_CASELOWER_LOCAL_PART,
+ CONTROL_CUTTHROUGH_DELIVERY,
+ CONTROL_DEBUG,
+#ifndef DISABLE_DKIM
+ CONTROL_DKIM_VERIFY,
+#endif
+#ifdef SUPPORT_DMARC
+ CONTROL_DMARC_VERIFY,
+ CONTROL_DMARC_FORENSIC,
+#endif
+ CONTROL_DSCP,
+ CONTROL_ENFORCE_SYNC,
+ CONTROL_ERROR, /* pseudo-value for decode errors */
+ CONTROL_FAKEDEFER,
+ CONTROL_FAKEREJECT,
+ CONTROL_FREEZE,
+
+ CONTROL_NO_CALLOUT_FLUSH,
+ CONTROL_NO_DELAY_FLUSH,
+ CONTROL_NO_ENFORCE_SYNC,
+#ifdef WITH_CONTENT_SCAN
+ CONTROL_NO_MBOX_UNSPOOL,
+#endif
+ CONTROL_NO_MULTILINE,
+ CONTROL_NO_PIPELINING,
+
+ CONTROL_QUEUE,
+ CONTROL_SUBMISSION,
+ CONTROL_SUPPRESS_LOCAL_FIXUPS,
+#ifdef SUPPORT_I18N
+ CONTROL_UTF8_DOWNCONVERT,
+#endif
+};
+
+
+
+/* Structure listing various control arguments, with their characteristics.
+For each control, there's a bitmap of dis-allowed times. For some, it is easier
+to specify the negation of a small number of allowed times. */
+
+typedef struct control_def {
+ uschar *name;
+ BOOL has_option; /* Has /option(s) following */
+ unsigned forbids; /* bitmap of dis-allowed times */
+} control_def;
+
+static control_def controls_list[] = {
+ /* name has_option forbids */
+[CONTROL_AUTH_UNADVERTISED] =
+ { US"allow_auth_unadvertised", FALSE,
+ (unsigned)
+ ~(ACL_BIT_CONNECT | ACL_BIT_HELO)
+ },
+#ifdef EXPERIMENTAL_BRIGHTMAIL
+[CONTROL_BMI_RUN] =
+ { US"bmi_run", FALSE, 0 },
+#endif
+[CONTROL_CASEFUL_LOCAL_PART] =
+ { US"caseful_local_part", FALSE, (unsigned) ~ACL_BIT_RCPT },
+[CONTROL_CASELOWER_LOCAL_PART] =
+ { US"caselower_local_part", FALSE, (unsigned) ~ACL_BIT_RCPT },
+[CONTROL_CUTTHROUGH_DELIVERY] =
+ { US"cutthrough_delivery", TRUE, 0 },
+[CONTROL_DEBUG] =
+ { US"debug", TRUE, 0 },
+
+#ifndef DISABLE_DKIM
+[CONTROL_DKIM_VERIFY] =
+ { US"dkim_disable_verify", FALSE,
+ ACL_BIT_DATA | ACL_BIT_NOTSMTP |
+# ifndef DISABLE_PRDR
+ ACL_BIT_PRDR |
+# endif
+ ACL_BIT_NOTSMTP_START
+ },
+#endif
+
+#ifdef SUPPORT_DMARC
+[CONTROL_DMARC_VERIFY] =
+ { US"dmarc_disable_verify", FALSE,
+ ACL_BIT_DATA | ACL_BIT_NOTSMTP | ACL_BIT_NOTSMTP_START
+ },
+[CONTROL_DMARC_FORENSIC] =
+ { US"dmarc_enable_forensic", FALSE,
+ ACL_BIT_DATA | ACL_BIT_NOTSMTP | ACL_BIT_NOTSMTP_START
+ },
+#endif
+
+[CONTROL_DSCP] =
+ { US"dscp", TRUE,
+ ACL_BIT_NOTSMTP | ACL_BIT_NOTSMTP_START | ACL_BIT_NOTQUIT
+ },
+[CONTROL_ENFORCE_SYNC] =
+ { US"enforce_sync", FALSE,
+ ACL_BIT_NOTSMTP | ACL_BIT_NOTSMTP_START
+ },
+
+ /* Pseudo-value for decode errors */
+[CONTROL_ERROR] =
+ { US"error", FALSE, 0 },
+
+[CONTROL_FAKEDEFER] =
+ { US"fakedefer", TRUE,
+ (unsigned)
+ ~(ACL_BIT_MAIL | ACL_BIT_RCPT |
+ ACL_BIT_PREDATA | ACL_BIT_DATA |
+#ifndef DISABLE_PRDR
+ ACL_BIT_PRDR |
+#endif
+ ACL_BIT_MIME)
+ },
+[CONTROL_FAKEREJECT] =
+ { US"fakereject", TRUE,
+ (unsigned)
+ ~(ACL_BIT_MAIL | ACL_BIT_RCPT |
+ ACL_BIT_PREDATA | ACL_BIT_DATA |
+#ifndef DISABLE_PRDR
+ ACL_BIT_PRDR |
+#endif
+ ACL_BIT_MIME)
+ },
+[CONTROL_FREEZE] =
+ { US"freeze", TRUE,
+ (unsigned)
+ ~(ACL_BIT_MAIL | ACL_BIT_RCPT |
+ ACL_BIT_PREDATA | ACL_BIT_DATA |
+ // ACL_BIT_PRDR| /* Not allow one user to freeze for all */
+ ACL_BIT_NOTSMTP | ACL_BIT_MIME)
+ },
+
+[CONTROL_NO_CALLOUT_FLUSH] =
+ { US"no_callout_flush", FALSE,
+ ACL_BIT_NOTSMTP | ACL_BIT_NOTSMTP_START
+ },
+[CONTROL_NO_DELAY_FLUSH] =
+ { US"no_delay_flush", FALSE,
+ ACL_BIT_NOTSMTP | ACL_BIT_NOTSMTP_START
+ },
+
+[CONTROL_NO_ENFORCE_SYNC] =
+ { US"no_enforce_sync", FALSE,
+ ACL_BIT_NOTSMTP | ACL_BIT_NOTSMTP_START
+ },
+#ifdef WITH_CONTENT_SCAN
+[CONTROL_NO_MBOX_UNSPOOL] =
+ { US"no_mbox_unspool", FALSE,
+ (unsigned)
+ ~(ACL_BIT_MAIL | ACL_BIT_RCPT |
+ ACL_BIT_PREDATA | ACL_BIT_DATA |
+ // ACL_BIT_PRDR| /* Not allow one user to freeze for all */
+ ACL_BIT_MIME)
+ },
+#endif
+[CONTROL_NO_MULTILINE] =
+ { US"no_multiline_responses", FALSE,
+ ACL_BIT_NOTSMTP | ACL_BIT_NOTSMTP_START
+ },
+[CONTROL_NO_PIPELINING] =
+ { US"no_pipelining", FALSE,
+ ACL_BIT_NOTSMTP | ACL_BIT_NOTSMTP_START
+ },
+
+[CONTROL_QUEUE] =
+ { US"queue", TRUE,
+ (unsigned)
+ ~(ACL_BIT_MAIL | ACL_BIT_RCPT |
+ ACL_BIT_PREDATA | ACL_BIT_DATA |
+ // ACL_BIT_PRDR| /* Not allow one user to freeze for all */
+ ACL_BIT_NOTSMTP | ACL_BIT_MIME)
+ },
+
+[CONTROL_SUBMISSION] =
+ { US"submission", TRUE,
+ (unsigned)
+ ~(ACL_BIT_MAIL | ACL_BIT_RCPT | ACL_BIT_PREDATA)
+ },
+[CONTROL_SUPPRESS_LOCAL_FIXUPS] =
+ { US"suppress_local_fixups", FALSE,
+ (unsigned)
+ ~(ACL_BIT_MAIL | ACL_BIT_RCPT | ACL_BIT_PREDATA |
+ ACL_BIT_NOTSMTP_START)
+ },
+#ifdef SUPPORT_I18N
+[CONTROL_UTF8_DOWNCONVERT] =
+ { US"utf8_downconvert", TRUE, (unsigned) ~(ACL_BIT_RCPT | ACL_BIT_VRFY)
+ }
+#endif
+};
+
+/* Support data structures for Client SMTP Authorization. acl_verify_csa()
+caches its result in a tree to avoid repeated DNS queries. The result is an
+integer code which is used as an index into the following tables of
+explanatory strings and verification return codes. */
+
+static tree_node *csa_cache = NULL;
+
+enum { CSA_UNKNOWN, CSA_OK, CSA_DEFER_SRV, CSA_DEFER_ADDR,
+ CSA_FAIL_EXPLICIT, CSA_FAIL_DOMAIN, CSA_FAIL_NOADDR, CSA_FAIL_MISMATCH };
+
+/* The acl_verify_csa() return code is translated into an acl_verify() return
+code using the following table. It is OK unless the client is definitely not
+authorized. This is because CSA is supposed to be optional for sending sites,
+so recipients should not be too strict about checking it - especially because
+DNS problems are quite likely to occur. It's possible to use $csa_status in
+further ACL conditions to distinguish ok, unknown, and defer if required, but
+the aim is to make the usual configuration simple. */
+
+static int csa_return_code[] = {
+ [CSA_UNKNOWN] = OK,
+ [CSA_OK] = OK,
+ [CSA_DEFER_SRV] = OK,
+ [CSA_DEFER_ADDR] = OK,
+ [CSA_FAIL_EXPLICIT] = FAIL,
+ [CSA_FAIL_DOMAIN] = FAIL,
+ [CSA_FAIL_NOADDR] = FAIL,
+ [CSA_FAIL_MISMATCH] = FAIL
+};
+
+static uschar *csa_status_string[] = {
+ [CSA_UNKNOWN] = US"unknown",
+ [CSA_OK] = US"ok",
+ [CSA_DEFER_SRV] = US"defer",
+ [CSA_DEFER_ADDR] = US"defer",
+ [CSA_FAIL_EXPLICIT] = US"fail",
+ [CSA_FAIL_DOMAIN] = US"fail",
+ [CSA_FAIL_NOADDR] = US"fail",
+ [CSA_FAIL_MISMATCH] = US"fail"
+};
+
+static uschar *csa_reason_string[] = {
+ [CSA_UNKNOWN] = US"unknown",
+ [CSA_OK] = US"ok",
+ [CSA_DEFER_SRV] = US"deferred (SRV lookup failed)",
+ [CSA_DEFER_ADDR] = US"deferred (target address lookup failed)",
+ [CSA_FAIL_EXPLICIT] = US"failed (explicit authorization required)",
+ [CSA_FAIL_DOMAIN] = US"failed (host name not authorized)",
+ [CSA_FAIL_NOADDR] = US"failed (no authorized addresses)",
+ [CSA_FAIL_MISMATCH] = US"failed (client address mismatch)"
+};
+
+/* Options for the ratelimit condition. Note that there are two variants of
+the per_rcpt option, depending on the ACL that is used to measure the rate.
+However any ACL must be able to look up per_rcpt rates in /noupdate mode,
+so the two variants must have the same internal representation as well as
+the same configuration string. */
+
+enum {
+ RATE_PER_WHAT, RATE_PER_CLASH, RATE_PER_ADDR, RATE_PER_BYTE, RATE_PER_CMD,
+ RATE_PER_CONN, RATE_PER_MAIL, RATE_PER_RCPT, RATE_PER_ALLRCPTS
+};
+
+#define RATE_SET(var,new) \
+ (((var) == RATE_PER_WHAT) ? ((var) = RATE_##new) : ((var) = RATE_PER_CLASH))
+
+static uschar *ratelimit_option_string[] = {
+ [RATE_PER_WHAT] = US"?",
+ [RATE_PER_CLASH] = US"!",
+ [RATE_PER_ADDR] = US"per_addr",
+ [RATE_PER_BYTE] = US"per_byte",
+ [RATE_PER_CMD] = US"per_cmd",
+ [RATE_PER_CONN] = US"per_conn",
+ [RATE_PER_MAIL] = US"per_mail",
+ [RATE_PER_RCPT] = US"per_rcpt",
+ [RATE_PER_ALLRCPTS] = US"per_rcpt"
+};
+
+/* Enable recursion between acl_check_internal() and acl_check_condition() */
+
+static int acl_check_wargs(int, address_item *, const uschar *, uschar **,
+ uschar **);
+
+
+/*************************************************
+* Find control in list *
+*************************************************/
+
+/* The lists are always in order, so binary chop can be used.
+
+Arguments:
+ name the control name to search for
+ ol the first entry in the control list
+ last one more than the offset of the last entry in the control list
+
+Returns: index of a control entry, or -1 if not found
+*/
+
+static int
+find_control(const uschar * name, control_def * ol, int last)
+{
+for (int first = 0; last > first; )
+ {
+ int middle = (first + last)/2;
+ uschar * s = ol[middle].name;
+ int c = Ustrncmp(name, s, Ustrlen(s));
+ if (c == 0) return middle;
+ else if (c > 0) first = middle + 1;
+ else last = middle;
+ }
+return -1;
+}
+
+
+
+/*************************************************
+* Pick out condition from list *
+*************************************************/
+
+/* Use a binary chop method
+
+Arguments:
+ name name to find
+ list list of conditions
+ end size of list
+
+Returns: offset in list, or -1 if not found
+*/
+
+static int
+acl_checkcondition(uschar * name, condition_def * list, int end)
+{
+for (int start = 0; start < end; )
+ {
+ int mid = (start + end)/2;
+ int c = Ustrcmp(name, list[mid].name);
+ if (c == 0) return mid;
+ if (c < 0) end = mid;
+ else start = mid + 1;
+ }
+return -1;
+}
+
+
+/*************************************************
+* Pick out name from list *
+*************************************************/
+
+/* Use a binary chop method
+
+Arguments:
+ name name to find
+ list list of names
+ end size of list
+
+Returns: offset in list, or -1 if not found
+*/
+
+static int
+acl_checkname(uschar *name, uschar **list, int end)
+{
+for (int start = 0; start < end; )
+ {
+ int mid = (start + end)/2;
+ int c = Ustrcmp(name, list[mid]);
+ if (c == 0) return mid;
+ if (c < 0) end = mid; else start = mid + 1;
+ }
+
+return -1;
+}
+
+
+/*************************************************
+* Read and parse one ACL *
+*************************************************/
+
+/* This function is called both from readconf in order to parse the ACLs in the
+configuration file, and also when an ACL is encountered dynamically (e.g. as
+the result of an expansion). It is given a function to call in order to
+retrieve the lines of the ACL. This function handles skipping comments and
+blank lines (where relevant).
+
+Arguments:
+ func function to get next line of ACL
+ error where to put an error message
+
+Returns: pointer to ACL, or NULL
+ NULL can be legal (empty ACL); in this case error will be NULL
+*/
+
+acl_block *
+acl_read(uschar *(*func)(void), uschar **error)
+{
+acl_block *yield = NULL;
+acl_block **lastp = &yield;
+acl_block *this = NULL;
+acl_condition_block *cond;
+acl_condition_block **condp = NULL;
+uschar * s;
+
+*error = NULL;
+
+while ((s = (*func)()))
+ {
+ int v, c;
+ BOOL negated = FALSE;
+ uschar *saveline = s;
+ uschar name[EXIM_DRIVERNAME_MAX];
+
+ /* Conditions (but not verbs) are allowed to be negated by an initial
+ exclamation mark. */
+
+ if (Uskip_whitespace(&s) == '!')
+ {
+ negated = TRUE;
+ s++;
+ }
+
+ /* Read the name of a verb or a condition, or the start of a new ACL, which
+ can be started by a name, or by a macro definition. */
+
+ s = readconf_readname(name, sizeof(name), s);
+ if (*s == ':' || (isupper(name[0]) && *s == '=')) return yield;
+
+ /* If a verb is unrecognized, it may be another condition or modifier that
+ continues the previous verb. */
+
+ if ((v = acl_checkname(name, verbs, nelem(verbs))) < 0)
+ {
+ if (!this)
+ {
+ *error = string_sprintf("unknown ACL verb \"%s\" in \"%s\"", name,
+ saveline);
+ return NULL;
+ }
+ }
+
+ /* New verb */
+
+ else
+ {
+ if (negated)
+ {
+ *error = string_sprintf("malformed ACL line \"%s\"", saveline);
+ return NULL;
+ }
+ this = store_get(sizeof(acl_block), FALSE);
+ *lastp = this;
+ lastp = &(this->next);
+ this->next = NULL;
+ this->condition = NULL;
+ this->verb = v;
+ this->srcline = config_lineno; /* for debug output */
+ this->srcfile = config_filename; /**/
+ condp = &(this->condition);
+ if (*s == 0) continue; /* No condition on this line */
+ if (*s == '!')
+ {
+ negated = TRUE;
+ s++;
+ }
+ s = readconf_readname(name, sizeof(name), s); /* Condition name */
+ }
+
+ /* Handle a condition or modifier. */
+
+ if ((c = acl_checkcondition(name, conditions, nelem(conditions))) < 0)
+ {
+ *error = string_sprintf("unknown ACL condition/modifier in \"%s\"",
+ saveline);
+ return NULL;
+ }
+
+ /* The modifiers may not be negated */
+
+ if (negated && conditions[c].is_modifier)
+ {
+ *error = string_sprintf("ACL error: negation is not allowed with "
+ "\"%s\"", conditions[c].name);
+ return NULL;
+ }
+
+ /* ENDPASS may occur only with ACCEPT or DISCARD. */
+
+ if (c == ACLC_ENDPASS &&
+ this->verb != ACL_ACCEPT &&
+ this->verb != ACL_DISCARD)
+ {
+ *error = string_sprintf("ACL error: \"%s\" is not allowed with \"%s\"",
+ conditions[c].name, verbs[this->verb]);
+ return NULL;
+ }
+
+ cond = store_get(sizeof(acl_condition_block), FALSE);
+ cond->next = NULL;
+ cond->type = c;
+ cond->u.negated = negated;
+
+ *condp = cond;
+ condp = &(cond->next);
+
+ /* The "set" modifier is different in that its argument is "name=value"
+ rather than just a value, and we can check the validity of the name, which
+ gives us a variable name to insert into the data block. The original ACL
+ variable names were acl_c0 ... acl_c9 and acl_m0 ... acl_m9. This was
+ extended to 20 of each type, but after that people successfully argued for
+ arbitrary names. In the new scheme, the names must start with acl_c or acl_m.
+ After that, we allow alphanumerics and underscores, but the first character
+ after c or m must be a digit or an underscore. This retains backwards
+ compatibility. */
+
+ if (c == ACLC_SET)
+#ifndef DISABLE_DKIM
+ if ( Ustrncmp(s, "dkim_verify_status", 18) == 0
+ || Ustrncmp(s, "dkim_verify_reason", 18) == 0)
+ {
+ uschar * endptr = s+18;
+
+ if (isalnum(*endptr))
+ {
+ *error = string_sprintf("invalid variable name after \"set\" in ACL "
+ "modifier \"set %s\" "
+ "(only \"dkim_verify_status\" or \"dkim_verify_reason\" permitted)",
+ s);
+ return NULL;
+ }
+ cond->u.varname = string_copyn(s, 18);
+ s = endptr;
+ Uskip_whitespace(&s);
+ }
+ else
+#endif
+ {
+ uschar *endptr;
+
+ if (Ustrncmp(s, "acl_c", 5) != 0 && Ustrncmp(s, "acl_m", 5) != 0)
+ {
+ *error = string_sprintf("invalid variable name after \"set\" in ACL "
+ "modifier \"set %s\" (must start \"acl_c\" or \"acl_m\")", s);
+ return NULL;
+ }
+
+ endptr = s + 5;
+ if (!isdigit(*endptr) && *endptr != '_')
+ {
+ *error = string_sprintf("invalid variable name after \"set\" in ACL "
+ "modifier \"set %s\" (digit or underscore must follow acl_c or acl_m)",
+ s);
+ return NULL;
+ }
+
+ while (*endptr && *endptr != '=' && !isspace(*endptr))
+ {
+ if (!isalnum(*endptr) && *endptr != '_')
+ {
+ *error = string_sprintf("invalid character \"%c\" in variable name "
+ "in ACL modifier \"set %s\"", *endptr, s);
+ return NULL;
+ }
+ endptr++;
+ }
+
+ cond->u.varname = string_copyn(s + 4, endptr - s - 4);
+ s = endptr;
+ Uskip_whitespace(&s);
+ }
+
+ /* For "set", we are now positioned for the data. For the others, only
+ "endpass" has no data */
+
+ if (c != ACLC_ENDPASS)
+ {
+ if (*s++ != '=')
+ {
+ *error = string_sprintf("\"=\" missing after ACL \"%s\" %s", name,
+ conditions[c].is_modifier ? US"modifier" : US"condition");
+ return NULL;
+ }
+ Uskip_whitespace(&s);
+ cond->arg = string_copy(s);
+ }
+ }
+
+return yield;
+}
+
+
+
+/*************************************************
+* Set up added header line(s) *
+*************************************************/
+
+/* This function is called by the add_header modifier, and also from acl_warn()
+to implement the now-deprecated way of adding header lines using "message" on a
+"warn" verb. The argument is treated as a sequence of header lines which are
+added to a chain, provided there isn't an identical one already there.
+
+Argument: string of header lines
+Returns: nothing
+*/
+
+static void
+setup_header(const uschar *hstring)
+{
+const uschar *p, *q;
+int hlen = Ustrlen(hstring);
+
+/* Ignore any leading newlines */
+while (*hstring == '\n') hstring++, hlen--;
+
+/* An empty string does nothing; ensure exactly one final newline. */
+if (hlen <= 0) return;
+if (hstring[--hlen] != '\n') /* no newline */
+ q = string_sprintf("%s\n", hstring);
+else if (hstring[hlen-1] == '\n') /* double newline */
+ {
+ uschar * s = string_copy(hstring);
+ while(s[--hlen] == '\n')
+ s[hlen+1] = '\0';
+ q = s;
+ }
+else
+ q = hstring;
+
+/* Loop for multiple header lines, taking care about continuations */
+
+for (p = q; *p; p = q)
+ {
+ const uschar *s;
+ uschar * hdr;
+ int newtype = htype_add_bot;
+ header_line **hptr = &acl_added_headers;
+
+ /* Find next header line within the string */
+
+ for (;;)
+ {
+ q = Ustrchr(q, '\n'); /* we know there was a newline */
+ if (*++q != ' ' && *q != '\t') break;
+ }
+
+ /* If the line starts with a colon, interpret the instruction for where to
+ add it. This temporarily sets up a new type. */
+
+ if (*p == ':')
+ {
+ if (strncmpic(p, US":after_received:", 16) == 0)
+ {
+ newtype = htype_add_rec;
+ p += 16;
+ }
+ else if (strncmpic(p, US":at_start_rfc:", 14) == 0)
+ {
+ newtype = htype_add_rfc;
+ p += 14;
+ }
+ else if (strncmpic(p, US":at_start:", 10) == 0)
+ {
+ newtype = htype_add_top;
+ p += 10;
+ }
+ else if (strncmpic(p, US":at_end:", 8) == 0)
+ {
+ newtype = htype_add_bot;
+ p += 8;
+ }
+ while (*p == ' ' || *p == '\t') p++;
+ }
+
+ /* See if this line starts with a header name, and if not, add X-ACL-Warn:
+ to the front of it. */
+
+ for (s = p; s < q - 1; s++)
+ if (*s == ':' || !isgraph(*s)) break;
+
+ hdr = string_sprintf("%s%.*s", *s == ':' ? "" : "X-ACL-Warn: ", (int) (q - p), p);
+ hlen = Ustrlen(hdr);
+
+ /* See if this line has already been added */
+
+ while (*hptr)
+ {
+ if (Ustrncmp((*hptr)->text, hdr, hlen) == 0) break;
+ hptr = &(*hptr)->next;
+ }
+
+ /* Add if not previously present */
+
+ if (!*hptr)
+ {
+ /* The header_line struct itself is not tainted, though it points to
+ possibly tainted data. */
+ header_line * h = store_get(sizeof(header_line), FALSE);
+ h->text = hdr;
+ h->next = NULL;
+ h->type = newtype;
+ h->slen = hlen;
+ *hptr = h;
+ hptr = &h->next;
+ }
+ }
+}
+
+
+
+/*************************************************
+* List the added header lines *
+*************************************************/
+uschar *
+fn_hdrs_added(void)
+{
+gstring * g = NULL;
+
+for (header_line * h = acl_added_headers; h; h = h->next)
+ {
+ int i = h->slen;
+ if (h->text[i-1] == '\n') i--;
+ g = string_append_listele_n(g, '\n', h->text, i);
+ }
+
+return g ? g->s : NULL;
+}
+
+
+/*************************************************
+* Set up removed header line(s) *
+*************************************************/
+
+/* This function is called by the remove_header modifier. The argument is
+treated as a sequence of header names which are added to a colon separated
+list, provided there isn't an identical one already there.
+
+Argument: string of header names
+Returns: nothing
+*/
+
+static void
+setup_remove_header(const uschar *hnames)
+{
+if (*hnames)
+ acl_removed_headers = acl_removed_headers
+ ? string_sprintf("%s : %s", acl_removed_headers, hnames)
+ : string_copy(hnames);
+}
+
+
+
+/*************************************************
+* Handle warnings *
+*************************************************/
+
+/* This function is called when a WARN verb's conditions are true. It adds to
+the message's headers, and/or writes information to the log. In each case, this
+only happens once (per message for headers, per connection for log).
+
+** NOTE: The header adding action using the "message" setting is historic, and
+its use is now deprecated. The new add_header modifier should be used instead.
+
+Arguments:
+ where ACL_WHERE_xxxx indicating which ACL this is
+ user_message message for adding to headers
+ log_message message for logging, if different
+
+Returns: nothing
+*/
+
+static void
+acl_warn(int where, uschar *user_message, uschar *log_message)
+{
+if (log_message != NULL && log_message != user_message)
+ {
+ uschar *text;
+ string_item *logged;
+
+ text = string_sprintf("%s Warning: %s", host_and_ident(TRUE),
+ string_printing(log_message));
+
+ /* If a sender verification has failed, and the log message is "sender verify
+ failed", add the failure message. */
+
+ if (sender_verified_failed != NULL &&
+ sender_verified_failed->message != NULL &&
+ strcmpic(log_message, US"sender verify failed") == 0)
+ text = string_sprintf("%s: %s", text, sender_verified_failed->message);
+
+ /* Search previously logged warnings. They are kept in malloc
+ store so they can be freed at the start of a new message. */
+
+ for (logged = acl_warn_logged; logged; logged = logged->next)
+ if (Ustrcmp(logged->text, text) == 0) break;
+
+ if (!logged)
+ {
+ int length = Ustrlen(text) + 1;
+ log_write(0, LOG_MAIN, "%s", text);
+ logged = store_malloc(sizeof(string_item) + length);
+ logged->text = US logged + sizeof(string_item);
+ memcpy(logged->text, text, length);
+ logged->next = acl_warn_logged;
+ acl_warn_logged = logged;
+ }
+ }
+
+/* If there's no user message, we are done. */
+
+if (!user_message) return;
+
+/* If this isn't a message ACL, we can't do anything with a user message.
+Log an error. */
+
+if (where > ACL_WHERE_NOTSMTP)
+ {
+ log_write(0, LOG_MAIN|LOG_PANIC, "ACL \"warn\" with \"message\" setting "
+ "found in a non-message (%s) ACL: cannot specify header lines here: "
+ "message ignored", acl_wherenames[where]);
+ return;
+ }
+
+/* The code for setting up header lines is now abstracted into a separate
+function so that it can be used for the add_header modifier as well. */
+
+setup_header(user_message);
+}
+
+
+
+/*************************************************
+* Verify and check reverse DNS *
+*************************************************/
+
+/* Called from acl_verify() below. We look up the host name(s) of the client IP
+address if this has not yet been done. The host_name_lookup() function checks
+that one of these names resolves to an address list that contains the client IP
+address, so we don't actually have to do the check here.
+
+Arguments:
+ user_msgptr pointer for user message
+ log_msgptr pointer for log message
+
+Returns: OK verification condition succeeded
+ FAIL verification failed
+ DEFER there was a problem verifying
+*/
+
+static int
+acl_verify_reverse(uschar **user_msgptr, uschar **log_msgptr)
+{
+int rc;
+
+user_msgptr = user_msgptr; /* stop compiler warning */
+
+/* Previous success */
+
+if (sender_host_name != NULL) return OK;
+
+/* Previous failure */
+
+if (host_lookup_failed)
+ {
+ *log_msgptr = string_sprintf("host lookup failed%s", host_lookup_msg);
+ return FAIL;
+ }
+
+/* Need to do a lookup */
+
+HDEBUG(D_acl)
+ debug_printf_indent("looking up host name to force name/address consistency check\n");
+
+if ((rc = host_name_lookup()) != OK)
+ {
+ *log_msgptr = rc == DEFER
+ ? US"host lookup deferred for reverse lookup check"
+ : string_sprintf("host lookup failed for reverse lookup check%s",
+ host_lookup_msg);
+ return rc; /* DEFER or FAIL */
+ }
+
+host_build_sender_fullhost();
+return OK;
+}
+
+
+
+/*************************************************
+* Check client IP address matches CSA target *
+*************************************************/
+
+/* Called from acl_verify_csa() below. This routine scans a section of a DNS
+response for address records belonging to the CSA target hostname. The section
+is specified by the reset argument, either RESET_ADDITIONAL or RESET_ANSWERS.
+If one of the addresses matches the client's IP address, then the client is
+authorized by CSA. If there are target IP addresses but none of them match
+then the client is using an unauthorized IP address. If there are no target IP
+addresses then the client cannot be using an authorized IP address. (This is
+an odd configuration - why didn't the SRV record have a weight of 1 instead?)
+
+Arguments:
+ dnsa the DNS answer block
+ dnss a DNS scan block for us to use
+ reset option specifying what portion to scan, as described above
+ target the target hostname to use for matching RR names
+
+Returns: CSA_OK successfully authorized
+ CSA_FAIL_MISMATCH addresses found but none matched
+ CSA_FAIL_NOADDR no target addresses found
+*/
+
+static int
+acl_verify_csa_address(dns_answer *dnsa, dns_scan *dnss, int reset,
+ uschar *target)
+{
+int rc = CSA_FAIL_NOADDR;
+
+for (dns_record * rr = dns_next_rr(dnsa, dnss, reset);
+ rr;
+ rr = dns_next_rr(dnsa, dnss, RESET_NEXT))
+ {
+ /* Check this is an address RR for the target hostname. */
+
+ if (rr->type != T_A
+ #if HAVE_IPV6
+ && rr->type != T_AAAA
+ #endif
+ ) continue;
+
+ if (strcmpic(target, rr->name) != 0) continue;
+
+ rc = CSA_FAIL_MISMATCH;
+
+ /* Turn the target address RR into a list of textual IP addresses and scan
+ the list. There may be more than one if it is an A6 RR. */
+
+ for (dns_address * da = dns_address_from_rr(dnsa, rr); da; da = da->next)
+ {
+ /* If the client IP address matches the target IP address, it's good! */
+
+ DEBUG(D_acl) debug_printf_indent("CSA target address is %s\n", da->address);
+
+ if (strcmpic(sender_host_address, da->address) == 0) return CSA_OK;
+ }
+ }
+
+/* If we found some target addresses but none of them matched, the client is
+using an unauthorized IP address, otherwise the target has no authorized IP
+addresses. */
+
+return rc;
+}
+
+
+
+/*************************************************
+* Verify Client SMTP Authorization *
+*************************************************/
+
+/* Called from acl_verify() below. This routine calls dns_lookup_special()
+to find the CSA SRV record corresponding to the domain argument, or
+$sender_helo_name if no argument is provided. It then checks that the
+client is authorized, and that its IP address corresponds to the SRV
+target's address by calling acl_verify_csa_address() above. The address
+should have been returned in the DNS response's ADDITIONAL section, but if
+not we perform another DNS lookup to get it.
+
+Arguments:
+ domain pointer to optional parameter following verify = csa
+
+Returns: CSA_UNKNOWN no valid CSA record found
+ CSA_OK successfully authorized
+ CSA_FAIL_* client is definitely not authorized
+ CSA_DEFER_* there was a DNS problem
+*/
+
+static int
+acl_verify_csa(const uschar *domain)
+{
+tree_node *t;
+const uschar *found;
+int priority, weight, port;
+dns_answer * dnsa = store_get_dns_answer();
+dns_scan dnss;
+dns_record *rr;
+int rc, type;
+uschar target[256];
+
+/* Work out the domain we are using for the CSA lookup. The default is the
+client's HELO domain. If the client has not said HELO, use its IP address
+instead. If it's a local client (exim -bs), CSA isn't applicable. */
+
+while (isspace(*domain) && *domain != '\0') ++domain;
+if (*domain == '\0') domain = sender_helo_name;
+if (domain == NULL) domain = sender_host_address;
+if (sender_host_address == NULL) return CSA_UNKNOWN;
+
+/* If we have an address literal, strip off the framing ready for turning it
+into a domain. The framing consists of matched square brackets possibly
+containing a keyword and a colon before the actual IP address. */
+
+if (domain[0] == '[')
+ {
+ const uschar *start = Ustrchr(domain, ':');
+ if (start == NULL) start = domain;
+ domain = string_copyn(start + 1, Ustrlen(start) - 2);
+ }
+
+/* Turn domains that look like bare IP addresses into domains in the reverse
+DNS. This code also deals with address literals and $sender_host_address. It's
+not quite kosher to treat bare domains such as EHLO 192.0.2.57 the same as
+address literals, but it's probably the most friendly thing to do. This is an
+extension to CSA, so we allow it to be turned off for proper conformance. */
+
+if (string_is_ip_address(domain, NULL) != 0)
+ {
+ if (!dns_csa_use_reverse) return CSA_UNKNOWN;
+ domain = dns_build_reverse(domain);
+ }
+
+/* Find out if we've already done the CSA check for this domain. If we have,
+return the same result again. Otherwise build a new cached result structure
+for this domain. The name is filled in now, and the value is filled in when
+we return from this function. */
+
+t = tree_search(csa_cache, domain);
+if (t != NULL) return t->data.val;
+
+t = store_get_perm(sizeof(tree_node) + Ustrlen(domain), is_tainted(domain));
+Ustrcpy(t->name, domain);
+(void)tree_insertnode(&csa_cache, t);
+
+/* Now we are ready to do the actual DNS lookup(s). */
+
+found = domain;
+switch (dns_special_lookup(dnsa, domain, T_CSA, &found))
+ {
+ /* If something bad happened (most commonly DNS_AGAIN), defer. */
+
+ default:
+ return t->data.val = CSA_DEFER_SRV;
+
+ /* If we found nothing, the client's authorization is unknown. */
+
+ case DNS_NOMATCH:
+ case DNS_NODATA:
+ return t->data.val = CSA_UNKNOWN;
+
+ /* We got something! Go on to look at the reply in more detail. */
+
+ case DNS_SUCCEED:
+ break;
+ }
+
+/* Scan the reply for well-formed CSA SRV records. */
+
+for (rr = dns_next_rr(dnsa, &dnss, RESET_ANSWERS);
+ rr;
+ rr = dns_next_rr(dnsa, &dnss, RESET_NEXT)) if (rr->type == T_SRV)
+ {
+ const uschar * p = rr->data;
+
+ /* Extract the numerical SRV fields (p is incremented) */
+
+ GETSHORT(priority, p);
+ GETSHORT(weight, p);
+ GETSHORT(port, p);
+
+ DEBUG(D_acl)
+ debug_printf_indent("CSA priority=%d weight=%d port=%d\n", priority, weight, port);
+
+ /* Check the CSA version number */
+
+ if (priority != 1) continue;
+
+ /* If the domain does not have a CSA SRV record of its own (i.e. the domain
+ found by dns_special_lookup() is a parent of the one we asked for), we check
+ the subdomain assertions in the port field. At the moment there's only one
+ assertion: legitimate SMTP clients are all explicitly authorized with CSA
+ SRV records of their own. */
+
+ if (Ustrcmp(found, domain) != 0)
+ return t->data.val = port & 1 ? CSA_FAIL_EXPLICIT : CSA_UNKNOWN;
+
+ /* This CSA SRV record refers directly to our domain, so we check the value
+ in the weight field to work out the domain's authorization. 0 and 1 are
+ unauthorized; 3 means the client is authorized but we can't check the IP
+ address in order to authenticate it, so we treat it as unknown; values
+ greater than 3 are undefined. */
+
+ if (weight < 2) return t->data.val = CSA_FAIL_DOMAIN;
+
+ if (weight > 2) continue;
+
+ /* Weight == 2, which means the domain is authorized. We must check that the
+ client's IP address is listed as one of the SRV target addresses. Save the
+ target hostname then break to scan the additional data for its addresses. */
+
+ (void)dn_expand(dnsa->answer, dnsa->answer + dnsa->answerlen, p,
+ (DN_EXPAND_ARG4_TYPE)target, sizeof(target));
+
+ DEBUG(D_acl) debug_printf_indent("CSA target is %s\n", target);
+
+ break;
+ }
+
+/* If we didn't break the loop then no appropriate records were found. */
+
+if (!rr) return t->data.val = CSA_UNKNOWN;
+
+/* Do not check addresses if the target is ".", in accordance with RFC 2782.
+A target of "." indicates there are no valid addresses, so the client cannot
+be authorized. (This is an odd configuration because weight=2 target=. is
+equivalent to weight=1, but we check for it in order to keep load off the
+root name servers.) Note that dn_expand() turns "." into "". */
+
+if (Ustrcmp(target, "") == 0) return t->data.val = CSA_FAIL_NOADDR;
+
+/* Scan the additional section of the CSA SRV reply for addresses belonging
+to the target. If the name server didn't return any additional data (e.g.
+because it does not fully support SRV records), we need to do another lookup
+to obtain the target addresses; otherwise we have a definitive result. */
+
+rc = acl_verify_csa_address(dnsa, &dnss, RESET_ADDITIONAL, target);
+if (rc != CSA_FAIL_NOADDR) return t->data.val = rc;
+
+/* The DNS lookup type corresponds to the IP version used by the client. */
+
+#if HAVE_IPV6
+if (Ustrchr(sender_host_address, ':') != NULL)
+ type = T_AAAA;
+else
+#endif /* HAVE_IPV6 */
+ type = T_A;
+
+
+lookup_dnssec_authenticated = NULL;
+switch (dns_lookup(dnsa, target, type, NULL))
+ {
+ /* If something bad happened (most commonly DNS_AGAIN), defer. */
+
+ default:
+ return t->data.val = CSA_DEFER_ADDR;
+
+ /* If the query succeeded, scan the addresses and return the result. */
+
+ case DNS_SUCCEED:
+ rc = acl_verify_csa_address(dnsa, &dnss, RESET_ANSWERS, target);
+ if (rc != CSA_FAIL_NOADDR) return t->data.val = rc;
+ /* else fall through */
+
+ /* If the target has no IP addresses, the client cannot have an authorized
+ IP address. However, if the target site uses A6 records (not AAAA records)
+ we have to do yet another lookup in order to check them. */
+
+ case DNS_NOMATCH:
+ case DNS_NODATA:
+ return t->data.val = CSA_FAIL_NOADDR;
+ }
+}
+
+
+
+/*************************************************
+* Handle verification (address & other) *
+*************************************************/
+
+enum { VERIFY_REV_HOST_LKUP, VERIFY_CERT, VERIFY_HELO, VERIFY_CSA, VERIFY_HDR_SYNTAX,
+ VERIFY_NOT_BLIND, VERIFY_HDR_SNDR, VERIFY_SNDR, VERIFY_RCPT,
+ VERIFY_HDR_NAMES_ASCII, VERIFY_ARC
+ };
+typedef struct {
+ uschar * name;
+ int value;
+ unsigned where_allowed; /* bitmap */
+ BOOL no_options; /* Never has /option(s) following */
+ unsigned alt_opt_sep; /* >0 Non-/ option separator (custom parser) */
+ } verify_type_t;
+static verify_type_t verify_type_list[] = {
+ /* name value where no-opt opt-sep */
+ { US"reverse_host_lookup", VERIFY_REV_HOST_LKUP, (unsigned)~0, FALSE, 0 },
+ { US"certificate", VERIFY_CERT, (unsigned)~0, TRUE, 0 },
+ { US"helo", VERIFY_HELO, (unsigned)~0, TRUE, 0 },
+ { US"csa", VERIFY_CSA, (unsigned)~0, FALSE, 0 },
+ { US"header_syntax", VERIFY_HDR_SYNTAX, ACL_BIT_DATA | ACL_BIT_NOTSMTP, TRUE, 0 },
+ { US"not_blind", VERIFY_NOT_BLIND, ACL_BIT_DATA | ACL_BIT_NOTSMTP, FALSE, 0 },
+ { US"header_sender", VERIFY_HDR_SNDR, ACL_BIT_DATA | ACL_BIT_NOTSMTP, FALSE, 0 },
+ { US"sender", VERIFY_SNDR, ACL_BIT_MAIL | ACL_BIT_RCPT
+ |ACL_BIT_PREDATA | ACL_BIT_DATA | ACL_BIT_NOTSMTP,
+ FALSE, 6 },
+ { US"recipient", VERIFY_RCPT, ACL_BIT_RCPT, FALSE, 0 },
+ { US"header_names_ascii", VERIFY_HDR_NAMES_ASCII, ACL_BIT_DATA | ACL_BIT_NOTSMTP, TRUE, 0 },
+#ifdef EXPERIMENTAL_ARC
+ { US"arc", VERIFY_ARC, ACL_BIT_DATA, FALSE , 0 },
+#endif
+ };
+
+
+enum { CALLOUT_DEFER_OK, CALLOUT_NOCACHE, CALLOUT_RANDOM, CALLOUT_USE_SENDER,
+ CALLOUT_USE_POSTMASTER, CALLOUT_POSTMASTER, CALLOUT_FULLPOSTMASTER,
+ CALLOUT_MAILFROM, CALLOUT_POSTMASTER_MAILFROM, CALLOUT_MAXWAIT, CALLOUT_CONNECT,
+ CALLOUT_HOLD, CALLOUT_TIME /* TIME must be last */
+ };
+typedef struct {
+ uschar * name;
+ int value;
+ int flag;
+ BOOL has_option; /* Has =option(s) following */
+ BOOL timeval; /* Has a time value */
+ } callout_opt_t;
+static callout_opt_t callout_opt_list[] = {
+ /* name value flag has-opt has-time */
+ { US"defer_ok", CALLOUT_DEFER_OK, 0, FALSE, FALSE },
+ { US"no_cache", CALLOUT_NOCACHE, vopt_callout_no_cache, FALSE, FALSE },
+ { US"random", CALLOUT_RANDOM, vopt_callout_random, FALSE, FALSE },
+ { US"use_sender", CALLOUT_USE_SENDER, vopt_callout_recipsender, FALSE, FALSE },
+ { US"use_postmaster", CALLOUT_USE_POSTMASTER,vopt_callout_recippmaster, FALSE, FALSE },
+ { US"postmaster_mailfrom",CALLOUT_POSTMASTER_MAILFROM,0, TRUE, FALSE },
+ { US"postmaster", CALLOUT_POSTMASTER, 0, FALSE, FALSE },
+ { US"fullpostmaster", CALLOUT_FULLPOSTMASTER,vopt_callout_fullpm, FALSE, FALSE },
+ { US"mailfrom", CALLOUT_MAILFROM, 0, TRUE, FALSE },
+ { US"maxwait", CALLOUT_MAXWAIT, 0, TRUE, TRUE },
+ { US"connect", CALLOUT_CONNECT, 0, TRUE, TRUE },
+ { US"hold", CALLOUT_HOLD, vopt_callout_hold, FALSE, FALSE },
+ { NULL, CALLOUT_TIME, 0, FALSE, TRUE }
+ };
+
+
+
+/* This function implements the "verify" condition. It is called when
+encountered in any ACL, because some tests are almost always permitted. Some
+just don't make sense, and always fail (for example, an attempt to test a host
+lookup for a non-TCP/IP message). Others are restricted to certain ACLs.
+
+Arguments:
+ where where called from
+ addr the recipient address that the ACL is handling, or NULL
+ arg the argument of "verify"
+ user_msgptr pointer for user message
+ log_msgptr pointer for log message
+ basic_errno where to put verify errno
+
+Returns: OK verification condition succeeded
+ FAIL verification failed
+ DEFER there was a problem verifying
+ ERROR syntax error
+*/
+
+static int
+acl_verify(int where, address_item *addr, const uschar *arg,
+ uschar **user_msgptr, uschar **log_msgptr, int *basic_errno)
+{
+int sep = '/';
+int callout = -1;
+int callout_overall = -1;
+int callout_connect = -1;
+int verify_options = 0;
+int rc;
+BOOL verify_header_sender = FALSE;
+BOOL defer_ok = FALSE;
+BOOL callout_defer_ok = FALSE;
+BOOL no_details = FALSE;
+BOOL success_on_redirect = FALSE;
+address_item *sender_vaddr = NULL;
+uschar *verify_sender_address = NULL;
+uschar *pm_mailfrom = NULL;
+uschar *se_mailfrom = NULL;
+
+/* Some of the verify items have slash-separated options; some do not. Diagnose
+an error if options are given for items that don't expect them.
+*/
+
+uschar *slash = Ustrchr(arg, '/');
+const uschar *list = arg;
+uschar *ss = string_nextinlist(&list, &sep, NULL, 0);
+verify_type_t * vp;
+
+if (!ss) goto BAD_VERIFY;
+
+/* Handle name/address consistency verification in a separate function. */
+
+for (vp = verify_type_list;
+ CS vp < CS verify_type_list + sizeof(verify_type_list);
+ vp++
+ )
+ if (vp->alt_opt_sep ? strncmpic(ss, vp->name, vp->alt_opt_sep) == 0
+ : strcmpic (ss, vp->name) == 0)
+ break;
+if (CS vp >= CS verify_type_list + sizeof(verify_type_list))
+ goto BAD_VERIFY;
+
+if (vp->no_options && slash)
+ {
+ *log_msgptr = string_sprintf("unexpected '/' found in \"%s\" "
+ "(this verify item has no options)", arg);
+ return ERROR;
+ }
+if (!(vp->where_allowed & BIT(where)))
+ {
+ *log_msgptr = string_sprintf("cannot verify %s in ACL for %s",
+ vp->name, acl_wherenames[where]);
+ return ERROR;
+ }
+switch(vp->value)
+ {
+ case VERIFY_REV_HOST_LKUP:
+ if (!sender_host_address) return OK;
+ if ((rc = acl_verify_reverse(user_msgptr, log_msgptr)) == DEFER)
+ while ((ss = string_nextinlist(&list, &sep, NULL, 0)))
+ if (strcmpic(ss, US"defer_ok") == 0)
+ return OK;
+ return rc;
+
+ case VERIFY_CERT:
+ /* TLS certificate verification is done at STARTTLS time; here we just
+ test whether it was successful or not. (This is for optional verification; for
+ mandatory verification, the connection doesn't last this long.) */
+
+ if (tls_in.certificate_verified) return OK;
+ *user_msgptr = US"no verified certificate";
+ return FAIL;
+
+ case VERIFY_HELO:
+ /* We can test the result of optional HELO verification that might have
+ occurred earlier. If not, we can attempt the verification now. */
+
+ if (!f.helo_verified && !f.helo_verify_failed) smtp_verify_helo();
+ return f.helo_verified ? OK : FAIL;
+
+ case VERIFY_CSA:
+ /* Do Client SMTP Authorization checks in a separate function, and turn the
+ result code into user-friendly strings. */
+
+ rc = acl_verify_csa(list);
+ *log_msgptr = *user_msgptr = string_sprintf("client SMTP authorization %s",
+ csa_reason_string[rc]);
+ csa_status = csa_status_string[rc];
+ DEBUG(D_acl) debug_printf_indent("CSA result %s\n", csa_status);
+ return csa_return_code[rc];
+
+#ifdef EXPERIMENTAL_ARC
+ case VERIFY_ARC:
+ { /* Do Authenticated Received Chain checks in a separate function. */
+ const uschar * condlist = CUS string_nextinlist(&list, &sep, NULL, 0);
+ int csep = 0;
+ uschar * cond;
+
+ if (!(arc_state = acl_verify_arc())) return DEFER;
+ DEBUG(D_acl) debug_printf_indent("ARC verify result %s %s%s%s\n", arc_state,
+ arc_state_reason ? "(":"", arc_state_reason, arc_state_reason ? ")":"");
+
+ if (!condlist) condlist = US"none:pass";
+ while ((cond = string_nextinlist(&condlist, &csep, NULL, 0)))
+ if (Ustrcmp(arc_state, cond) == 0) return OK;
+ return FAIL;
+ }
+#endif
+
+ case VERIFY_HDR_SYNTAX:
+ /* Check that all relevant header lines have the correct 5322-syntax. If there is
+ a syntax error, we return details of the error to the sender if configured to
+ send out full details. (But a "message" setting on the ACL can override, as
+ always). */
+
+ rc = verify_check_headers(log_msgptr);
+ if (rc != OK && *log_msgptr)
+ if (smtp_return_error_details)
+ *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
+ else
+ acl_verify_message = *log_msgptr;
+ return rc;
+
+ case VERIFY_HDR_NAMES_ASCII:
+ /* Check that all header names are true 7 bit strings
+ See RFC 5322, 2.2. and RFC 6532, 3. */
+
+ rc = verify_check_header_names_ascii(log_msgptr);
+ if (rc != OK && smtp_return_error_details && *log_msgptr)
+ *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
+ return rc;
+
+ case VERIFY_NOT_BLIND:
+ /* Check that no recipient of this message is "blind", that is, every envelope
+ recipient must be mentioned in either To: or Cc:. */
+ {
+ BOOL case_sensitive = TRUE;
+
+ while ((ss = string_nextinlist(&list, &sep, NULL, 0)))
+ if (strcmpic(ss, US"case_insensitive") == 0)
+ case_sensitive = FALSE;
+ else
+ {
+ *log_msgptr = string_sprintf("unknown option \"%s\" in ACL "
+ "condition \"verify %s\"", ss, arg);
+ return ERROR;
+ }
+
+ if ((rc = verify_check_notblind(case_sensitive)) != OK)
+ {
+ *log_msgptr = US"bcc recipient detected";
+ if (smtp_return_error_details)
+ *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
+ }
+ return rc;
+ }
+
+ /* The remaining verification tests check recipient and sender addresses,
+ either from the envelope or from the header. There are a number of
+ slash-separated options that are common to all of them. */
+
+ case VERIFY_HDR_SNDR:
+ verify_header_sender = TRUE;
+ break;
+
+ case VERIFY_SNDR:
+ /* In the case of a sender, this can optionally be followed by an address to use
+ in place of the actual sender (rare special-case requirement). */
+ {
+ uschar *s = ss + 6;
+ if (*s == 0)
+ verify_sender_address = sender_address;
+ else
+ {
+ while (isspace(*s)) s++;
+ if (*s++ != '=') goto BAD_VERIFY;
+ while (isspace(*s)) s++;
+ verify_sender_address = string_copy(s);
+ }
+ }
+ break;
+
+ case VERIFY_RCPT:
+ break;
+ }
+
+
+
+/* Remaining items are optional; they apply to sender and recipient
+verification, including "header sender" verification. */
+
+while ((ss = string_nextinlist(&list, &sep, NULL, 0)))
+ {
+ if (strcmpic(ss, US"defer_ok") == 0) defer_ok = TRUE;
+ else if (strcmpic(ss, US"no_details") == 0) no_details = TRUE;
+ else if (strcmpic(ss, US"success_on_redirect") == 0) success_on_redirect = TRUE;
+
+ /* These two old options are left for backwards compatibility */
+
+ else if (strcmpic(ss, US"callout_defer_ok") == 0)
+ {
+ callout_defer_ok = TRUE;
+ if (callout == -1) callout = CALLOUT_TIMEOUT_DEFAULT;
+ }
+
+ else if (strcmpic(ss, US"check_postmaster") == 0)
+ {
+ pm_mailfrom = US"";
+ if (callout == -1) callout = CALLOUT_TIMEOUT_DEFAULT;
+ }
+
+ /* The callout option has a number of sub-options, comma separated */
+
+ else if (strncmpic(ss, US"callout", 7) == 0)
+ {
+ callout = CALLOUT_TIMEOUT_DEFAULT;
+ ss += 7;
+ if (*ss != 0)
+ {
+ while (isspace(*ss)) ss++;
+ if (*ss++ == '=')
+ {
+ const uschar * sublist = ss;
+ int optsep = ',';
+ uschar buffer[256];
+ uschar * opt;
+
+ while (isspace(*sublist)) sublist++;
+ while ((opt = string_nextinlist(&sublist, &optsep, NULL, 0)))
+ {
+ callout_opt_t * op;
+ double period = 1.0F;
+
+ for (op= callout_opt_list; op->name; op++)
+ if (strncmpic(opt, op->name, Ustrlen(op->name)) == 0)
+ break;
+
+ verify_options |= op->flag;
+ if (op->has_option)
+ {
+ opt += Ustrlen(op->name);
+ while (isspace(*opt)) opt++;
+ if (*opt++ != '=')
+ {
+ *log_msgptr = string_sprintf("'=' expected after "
+ "\"%s\" in ACL verify condition \"%s\"", op->name, arg);
+ return ERROR;
+ }
+ while (isspace(*opt)) opt++;
+ }
+ if (op->timeval && (period = readconf_readtime(opt, 0, FALSE)) < 0)
+ {
+ *log_msgptr = string_sprintf("bad time value in ACL condition "
+ "\"verify %s\"", arg);
+ return ERROR;
+ }
+
+ switch(op->value)
+ {
+ case CALLOUT_DEFER_OK: callout_defer_ok = TRUE; break;
+ case CALLOUT_POSTMASTER: pm_mailfrom = US""; break;
+ case CALLOUT_FULLPOSTMASTER: pm_mailfrom = US""; break;
+ case CALLOUT_MAILFROM:
+ if (!verify_header_sender)
+ {
+ *log_msgptr = string_sprintf("\"mailfrom\" is allowed as a "
+ "callout option only for verify=header_sender (detected in ACL "
+ "condition \"%s\")", arg);
+ return ERROR;
+ }
+ se_mailfrom = string_copy(opt);
+ break;
+ case CALLOUT_POSTMASTER_MAILFROM: pm_mailfrom = string_copy(opt); break;
+ case CALLOUT_MAXWAIT: callout_overall = period; break;
+ case CALLOUT_CONNECT: callout_connect = period; break;
+ case CALLOUT_TIME: callout = period; break;
+ }
+ }
+ }
+ else
+ {
+ *log_msgptr = string_sprintf("'=' expected after \"callout\" in "
+ "ACL condition \"%s\"", arg);
+ return ERROR;
+ }
+ }
+ }
+
+ /* Option not recognized */
+
+ else
+ {
+ *log_msgptr = string_sprintf("unknown option \"%s\" in ACL "
+ "condition \"verify %s\"", ss, arg);
+ return ERROR;
+ }
+ }
+
+if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster)) ==
+ (vopt_callout_recipsender|vopt_callout_recippmaster))
+ {
+ *log_msgptr = US"only one of use_sender and use_postmaster can be set "
+ "for a recipient callout";
+ return ERROR;
+ }
+
+/* Handle sender-in-header verification. Default the user message to the log
+message if giving out verification details. */
+
+if (verify_header_sender)
+ {
+ int verrno;
+
+ if ((rc = verify_check_header_address(user_msgptr, log_msgptr, callout,
+ callout_overall, callout_connect, se_mailfrom, pm_mailfrom, verify_options,
+ &verrno)) != OK)
+ {
+ *basic_errno = verrno;
+ if (smtp_return_error_details)
+ {
+ if (!*user_msgptr && *log_msgptr)
+ *user_msgptr = string_sprintf("Rejected after DATA: %s", *log_msgptr);
+ if (rc == DEFER) f.acl_temp_details = TRUE;
+ }
+ }
+ }
+
+/* Handle a sender address. The default is to verify *the* sender address, but
+optionally a different address can be given, for special requirements. If the
+address is empty, we are dealing with a bounce message that has no sender, so
+we cannot do any checking. If the real sender address gets rewritten during
+verification (e.g. DNS widening), set the flag to stop it being rewritten again
+during message reception.
+
+A list of verified "sender" addresses is kept to try to avoid doing to much
+work repetitively when there are multiple recipients in a message and they all
+require sender verification. However, when callouts are involved, it gets too
+complicated because different recipients may require different callout options.
+Therefore, we always do a full sender verify when any kind of callout is
+specified. Caching elsewhere, for instance in the DNS resolver and in the
+callout handling, should ensure that this is not terribly inefficient. */
+
+else if (verify_sender_address)
+ {
+ if ((verify_options & (vopt_callout_recipsender|vopt_callout_recippmaster)))
+ {
+ *log_msgptr = US"use_sender or use_postmaster cannot be used for a "
+ "sender verify callout";
+ return ERROR;
+ }
+
+ sender_vaddr = verify_checked_sender(verify_sender_address);
+ if (sender_vaddr != NULL && /* Previously checked */
+ callout <= 0) /* No callout needed this time */
+ {
+ /* If the "routed" flag is set, it means that routing worked before, so
+ this check can give OK (the saved return code value, if set, belongs to a
+ callout that was done previously). If the "routed" flag is not set, routing
+ must have failed, so we use the saved return code. */
+
+ if (testflag(sender_vaddr, af_verify_routed))
+ rc = OK;
+ else
+ {
+ rc = sender_vaddr->special_action;
+ *basic_errno = sender_vaddr->basic_errno;
+ }
+ HDEBUG(D_acl) debug_printf_indent("using cached sender verify result\n");
+ }
+
+ /* Do a new verification, and cache the result. The cache is used to avoid
+ verifying the sender multiple times for multiple RCPTs when callouts are not
+ specified (see comments above).
+
+ The cache is also used on failure to give details in response to the first
+ RCPT that gets bounced for this reason. However, this can be suppressed by
+ the no_details option, which sets the flag that says "this detail has already
+ been sent". The cache normally contains just one address, but there may be
+ more in esoteric circumstances. */
+
+ else
+ {
+ BOOL routed = TRUE;
+ uschar *save_address_data = deliver_address_data;
+
+ sender_vaddr = deliver_make_addr(verify_sender_address, TRUE);
+#ifdef SUPPORT_I18N
+ if ((sender_vaddr->prop.utf8_msg = message_smtputf8))
+ {
+ sender_vaddr->prop.utf8_downcvt = message_utf8_downconvert == 1;
+ sender_vaddr->prop.utf8_downcvt_maybe = message_utf8_downconvert == -1;
+ }
+#endif
+ if (no_details) setflag(sender_vaddr, af_sverify_told);
+ if (verify_sender_address[0] != 0)
+ {
+ /* If this is the real sender address, save the unrewritten version
+ for use later in receive. Otherwise, set a flag so that rewriting the
+ sender in verify_address() does not update sender_address. */
+
+ if (verify_sender_address == sender_address)
+ sender_address_unrewritten = sender_address;
+ else
+ verify_options |= vopt_fake_sender;
+
+ if (success_on_redirect)
+ verify_options |= vopt_success_on_redirect;
+
+ /* The recipient, qualify, and expn options are never set in
+ verify_options. */
+
+ rc = verify_address(sender_vaddr, NULL, verify_options, callout,
+ callout_overall, callout_connect, se_mailfrom, pm_mailfrom, &routed);
+
+ HDEBUG(D_acl) debug_printf_indent("----------- end verify ------------\n");
+
+ if (rc != OK)
+ *basic_errno = sender_vaddr->basic_errno;
+ else
+ DEBUG(D_acl)
+ {
+ if (Ustrcmp(sender_vaddr->address, verify_sender_address) != 0)
+ debug_printf_indent("sender %s verified ok as %s\n",
+ verify_sender_address, sender_vaddr->address);
+ else
+ debug_printf_indent("sender %s verified ok\n",
+ verify_sender_address);
+ }
+ }
+ else
+ rc = OK; /* Null sender */
+
+ /* Cache the result code */
+
+ if (routed) setflag(sender_vaddr, af_verify_routed);
+ if (callout > 0) setflag(sender_vaddr, af_verify_callout);
+ sender_vaddr->special_action = rc;
+ sender_vaddr->next = sender_verified_list;
+ sender_verified_list = sender_vaddr;
+
+ /* Restore the recipient address data, which might have been clobbered by
+ the sender verification. */
+
+ deliver_address_data = save_address_data;
+ }
+
+ /* Put the sender address_data value into $sender_address_data */
+
+ sender_address_data = sender_vaddr->prop.address_data;
+ }
+
+/* A recipient address just gets a straightforward verify; again we must handle
+the DEFER overrides. */
+
+else
+ {
+ address_item addr2;
+
+ if (success_on_redirect)
+ verify_options |= vopt_success_on_redirect;
+
+ /* We must use a copy of the address for verification, because it might
+ get rewritten. */
+
+ addr2 = *addr;
+ rc = verify_address(&addr2, NULL, verify_options|vopt_is_recipient, callout,
+ callout_overall, callout_connect, se_mailfrom, pm_mailfrom, NULL);
+ HDEBUG(D_acl) debug_printf_indent("----------- end verify ------------\n");
+
+ *basic_errno = addr2.basic_errno;
+ *log_msgptr = addr2.message;
+ *user_msgptr = (addr2.user_message != NULL)?
+ addr2.user_message : addr2.message;
+
+ /* Allow details for temporary error if the address is so flagged. */
+ if (testflag((&addr2), af_pass_message)) f.acl_temp_details = TRUE;
+
+ /* Make $address_data visible */
+ deliver_address_data = addr2.prop.address_data;
+ }
+
+/* We have a result from the relevant test. Handle defer overrides first. */
+
+if (rc == DEFER && (defer_ok ||
+ (callout_defer_ok && *basic_errno == ERRNO_CALLOUTDEFER)))
+ {
+ HDEBUG(D_acl) debug_printf_indent("verify defer overridden by %s\n",
+ defer_ok? "defer_ok" : "callout_defer_ok");
+ rc = OK;
+ }
+
+/* If we've failed a sender, set up a recipient message, and point
+sender_verified_failed to the address item that actually failed. */
+
+if (rc != OK && verify_sender_address != NULL)
+ {
+ if (rc != DEFER)
+ *log_msgptr = *user_msgptr = US"Sender verify failed";
+ else if (*basic_errno != ERRNO_CALLOUTDEFER)
+ *log_msgptr = *user_msgptr = US"Could not complete sender verify";
+ else
+ {
+ *log_msgptr = US"Could not complete sender verify callout";
+ *user_msgptr = smtp_return_error_details? sender_vaddr->user_message :
+ *log_msgptr;
+ }
+
+ sender_verified_failed = sender_vaddr;
+ }
+
+/* Verifying an address messes up the values of $domain and $local_part,
+so reset them before returning if this is a RCPT ACL. */
+
+if (addr != NULL)
+ {
+ deliver_domain = addr->domain;
+ deliver_localpart = addr->local_part;
+ }
+return rc;
+
+/* Syntax errors in the verify argument come here. */
+
+BAD_VERIFY:
+*log_msgptr = string_sprintf("expected \"sender[=address]\", \"recipient\", "
+ "\"helo\", \"header_syntax\", \"header_sender\", \"header_names_ascii\" "
+ "or \"reverse_host_lookup\" at start of ACL condition "
+ "\"verify %s\"", arg);
+return ERROR;
+}
+
+
+
+
+/*************************************************
+* Check argument for control= modifier *
+*************************************************/
+
+/* Called from acl_check_condition() below.
+To handle the case "queue_only" we accept an _ in the
+initial / option-switch position.
+
+Arguments:
+ arg the argument string for control=
+ pptr set to point to the terminating character
+ where which ACL we are in
+ log_msgptr for error messages
+
+Returns: CONTROL_xxx value
+*/
+
+static int
+decode_control(const uschar *arg, const uschar **pptr, int where, uschar **log_msgptr)
+{
+int idx, len;
+control_def * d;
+uschar c;
+
+if ( (idx = find_control(arg, controls_list, nelem(controls_list))) < 0
+ || ( (c = arg[len = Ustrlen((d = controls_list+idx)->name)]) != 0
+ && (!d->has_option || c != '/' && c != '_')
+ ) )
+ {
+ *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
+ return CONTROL_ERROR;
+ }
+
+*pptr = arg + len;
+return idx;
+}
+
+
+
+
+/*************************************************
+* Return a ratelimit error *
+*************************************************/
+
+/* Called from acl_ratelimit() below
+
+Arguments:
+ log_msgptr for error messages
+ format format string
+ ... supplementary arguments
+
+Returns: ERROR
+*/
+
+static int
+ratelimit_error(uschar **log_msgptr, const char *format, ...)
+{
+va_list ap;
+gstring * g =
+ string_cat(NULL, US"error in arguments to \"ratelimit\" condition: ");
+
+va_start(ap, format);
+g = string_vformat(g, SVFMT_EXTEND|SVFMT_REBUFFER, format, ap);
+va_end(ap);
+
+gstring_release_unused(g);
+*log_msgptr = string_from_gstring(g);
+return ERROR;
+}
+
+
+
+
+/*************************************************
+* Handle rate limiting *
+*************************************************/
+
+/* Called by acl_check_condition() below to calculate the result
+of the ACL ratelimit condition.
+
+Note that the return value might be slightly unexpected: if the
+sender's rate is above the limit then the result is OK. This is
+similar to the dnslists condition, and is so that you can write
+ACL clauses like: defer ratelimit = 15 / 1h
+
+Arguments:
+ arg the option string for ratelimit=
+ where ACL_WHERE_xxxx indicating which ACL this is
+ log_msgptr for error messages
+
+Returns: OK - Sender's rate is above limit
+ FAIL - Sender's rate is below limit
+ DEFER - Problem opening ratelimit database
+ ERROR - Syntax error in options.
+*/
+
+static int
+acl_ratelimit(const uschar *arg, int where, uschar **log_msgptr)
+{
+double limit, period, count;
+uschar *ss;
+uschar *key = NULL;
+uschar *unique = NULL;
+int sep = '/';
+BOOL leaky = FALSE, strict = FALSE, readonly = FALSE;
+BOOL noupdate = FALSE, badacl = FALSE;
+int mode = RATE_PER_WHAT;
+int old_pool, rc;
+tree_node **anchor, *t;
+open_db dbblock, *dbm;
+int dbdb_size;
+dbdata_ratelimit *dbd;
+dbdata_ratelimit_unique *dbdb;
+struct timeval tv;
+
+/* Parse the first two options and record their values in expansion
+variables. These variables allow the configuration to have informative
+error messages based on rate limits obtained from a table lookup. */
+
+/* First is the maximum number of messages per period / maximum burst
+size, which must be greater than or equal to zero. Zero is useful for
+rate measurement as opposed to rate limiting. */
+
+if (!(sender_rate_limit = string_nextinlist(&arg, &sep, NULL, 0)))
+ return ratelimit_error(log_msgptr, "sender rate limit not set");
+
+limit = Ustrtod(sender_rate_limit, &ss);
+if (tolower(*ss) == 'k') { limit *= 1024.0; ss++; }
+else if (tolower(*ss) == 'm') { limit *= 1024.0*1024.0; ss++; }
+else if (tolower(*ss) == 'g') { limit *= 1024.0*1024.0*1024.0; ss++; }
+
+if (limit < 0.0 || *ss != '\0')
+ return ratelimit_error(log_msgptr,
+ "\"%s\" is not a positive number", sender_rate_limit);
+
+/* Second is the rate measurement period / exponential smoothing time
+constant. This must be strictly greater than zero, because zero leads to
+run-time division errors. */
+
+period = !(sender_rate_period = string_nextinlist(&arg, &sep, NULL, 0))
+ ? -1.0 : readconf_readtime(sender_rate_period, 0, FALSE);
+if (period <= 0.0)
+ return ratelimit_error(log_msgptr,
+ "\"%s\" is not a time value", sender_rate_period);
+
+/* By default we are counting one of something, but the per_rcpt,
+per_byte, and count options can change this. */
+
+count = 1.0;
+
+/* Parse the other options. */
+
+while ((ss = string_nextinlist(&arg, &sep, NULL, 0)))
+ {
+ if (strcmpic(ss, US"leaky") == 0) leaky = TRUE;
+ else if (strcmpic(ss, US"strict") == 0) strict = TRUE;
+ else if (strcmpic(ss, US"noupdate") == 0) noupdate = TRUE;
+ else if (strcmpic(ss, US"readonly") == 0) readonly = TRUE;
+ else if (strcmpic(ss, US"per_cmd") == 0) RATE_SET(mode, PER_CMD);
+ else if (strcmpic(ss, US"per_conn") == 0)
+ {
+ RATE_SET(mode, PER_CONN);
+ if (where == ACL_WHERE_NOTSMTP || where == ACL_WHERE_NOTSMTP_START)
+ badacl = TRUE;
+ }
+ else if (strcmpic(ss, US"per_mail") == 0)
+ {
+ RATE_SET(mode, PER_MAIL);
+ if (where > ACL_WHERE_NOTSMTP) badacl = TRUE;
+ }
+ else if (strcmpic(ss, US"per_rcpt") == 0)
+ {
+ /* If we are running in the RCPT ACL, then we'll count the recipients
+ one by one, but if we are running when we have accumulated the whole
+ list then we'll add them all in one batch. */
+ if (where == ACL_WHERE_RCPT)
+ RATE_SET(mode, PER_RCPT);
+ else if (where >= ACL_WHERE_PREDATA && where <= ACL_WHERE_NOTSMTP)
+ RATE_SET(mode, PER_ALLRCPTS), count = (double)recipients_count;
+ else if (where == ACL_WHERE_MAIL || where > ACL_WHERE_NOTSMTP)
+ RATE_SET(mode, PER_RCPT), badacl = TRUE;
+ }
+ else if (strcmpic(ss, US"per_byte") == 0)
+ {
+ /* If we have not yet received the message data and there was no SIZE
+ declaration on the MAIL command, then it's safe to just use a value of
+ zero and let the recorded rate decay as if nothing happened. */
+ RATE_SET(mode, PER_MAIL);
+ if (where > ACL_WHERE_NOTSMTP) badacl = TRUE;
+ else count = message_size < 0 ? 0.0 : (double)message_size;
+ }
+ else if (strcmpic(ss, US"per_addr") == 0)
+ {
+ RATE_SET(mode, PER_RCPT);
+ if (where != ACL_WHERE_RCPT) badacl = TRUE, unique = US"*";
+ else unique = string_sprintf("%s@%s", deliver_localpart, deliver_domain);
+ }
+ else if (strncmpic(ss, US"count=", 6) == 0)
+ {
+ uschar *e;
+ count = Ustrtod(ss+6, &e);
+ if (count < 0.0 || *e != '\0')
+ return ratelimit_error(log_msgptr, "\"%s\" is not a positive number", ss);
+ }
+ else if (strncmpic(ss, US"unique=", 7) == 0)
+ unique = string_copy(ss + 7);
+ else if (!key)
+ key = string_copy(ss);
+ else
+ key = string_sprintf("%s/%s", key, ss);
+ }
+
+/* Sanity check. When the badacl flag is set the update mode must either
+be readonly (which is the default if it is omitted) or, for backwards
+compatibility, a combination of noupdate and strict or leaky. */
+
+if (mode == RATE_PER_CLASH)
+ return ratelimit_error(log_msgptr, "conflicting per_* options");
+if (leaky + strict + readonly > 1)
+ return ratelimit_error(log_msgptr, "conflicting update modes");
+if (badacl && (leaky || strict) && !noupdate)
+ return ratelimit_error(log_msgptr,
+ "\"%s\" must not have /leaky or /strict option, or cannot be used in %s ACL",
+ ratelimit_option_string[mode], acl_wherenames[where]);
+
+/* Set the default values of any unset options. In readonly mode we
+perform the rate computation without any increment so that its value
+decays to eventually allow over-limit senders through. */
+
+if (noupdate) readonly = TRUE, leaky = strict = FALSE;
+if (badacl) readonly = TRUE;
+if (readonly) count = 0.0;
+if (!strict && !readonly) leaky = TRUE;
+if (mode == RATE_PER_WHAT) mode = RATE_PER_MAIL;
+
+/* Create the lookup key. If there is no explicit key, use sender_host_address.
+If there is no sender_host_address (e.g. -bs or acl_not_smtp) then we simply
+omit it. The smoothing constant (sender_rate_period) and the per_xxx options
+are added to the key because they alter the meaning of the stored data. */
+
+if (!key)
+ key = !sender_host_address ? US"" : sender_host_address;
+
+key = string_sprintf("%s/%s/%s%s",
+ sender_rate_period,
+ ratelimit_option_string[mode],
+ unique == NULL ? "" : "unique/",
+ key);
+
+HDEBUG(D_acl)
+ debug_printf_indent("ratelimit condition count=%.0f %.1f/%s\n", count, limit, key);
+
+/* See if we have already computed the rate by looking in the relevant tree.
+For per-connection rate limiting, store tree nodes and dbdata in the permanent
+pool so that they survive across resets. In readonly mode we only remember the
+result for the rest of this command in case a later command changes it. After
+this bit of logic the code is independent of the per_* mode. */
+
+old_pool = store_pool;
+
+if (readonly)
+ anchor = &ratelimiters_cmd;
+else switch(mode)
+ {
+ case RATE_PER_CONN:
+ anchor = &ratelimiters_conn;
+ store_pool = POOL_PERM;
+ break;
+ case RATE_PER_BYTE:
+ case RATE_PER_MAIL:
+ case RATE_PER_ALLRCPTS:
+ anchor = &ratelimiters_mail;
+ break;
+ case RATE_PER_ADDR:
+ case RATE_PER_CMD:
+ case RATE_PER_RCPT:
+ anchor = &ratelimiters_cmd;
+ break;
+ default:
+ anchor = NULL; /* silence an "unused" complaint */
+ log_write(0, LOG_MAIN|LOG_PANIC_DIE,
+ "internal ACL error: unknown ratelimit mode %d", mode);
+ break;
+ }
+
+if ((t = tree_search(*anchor, key)))
+ {
+ dbd = t->data.ptr;
+ /* The following few lines duplicate some of the code below. */
+ rc = (dbd->rate < limit)? FAIL : OK;
+ store_pool = old_pool;
+ sender_rate = string_sprintf("%.1f", dbd->rate);
+ HDEBUG(D_acl)
+ debug_printf_indent("ratelimit found pre-computed rate %s\n", sender_rate);
+ return rc;
+ }
+
+/* We aren't using a pre-computed rate, so get a previously recorded rate
+from the database, which will be updated and written back if required. */
+
+if (!(dbm = dbfn_open(US"ratelimit", O_RDWR, &dbblock, TRUE, TRUE)))
+ {
+ store_pool = old_pool;
+ sender_rate = NULL;
+ HDEBUG(D_acl) debug_printf_indent("ratelimit database not available\n");
+ *log_msgptr = US"ratelimit database not available";
+ return DEFER;
+ }
+dbdb = dbfn_read_with_length(dbm, key, &dbdb_size);
+dbd = NULL;
+
+gettimeofday(&tv, NULL);
+
+if (dbdb)
+ {
+ /* Locate the basic ratelimit block inside the DB data. */
+ HDEBUG(D_acl) debug_printf_indent("ratelimit found key in database\n");
+ dbd = &dbdb->dbd;
+
+ /* Forget the old Bloom filter if it is too old, so that we count each
+ repeating event once per period. We don't simply clear and re-use the old
+ filter because we want its size to change if the limit changes. Note that
+ we keep the dbd pointer for copying the rate into the new data block. */
+
+ if(unique && tv.tv_sec > dbdb->bloom_epoch + period)
+ {
+ HDEBUG(D_acl) debug_printf_indent("ratelimit discarding old Bloom filter\n");
+ dbdb = NULL;
+ }
+
+ /* Sanity check. */
+
+ if(unique && dbdb_size < sizeof(*dbdb))
+ {
+ HDEBUG(D_acl) debug_printf_indent("ratelimit discarding undersize Bloom filter\n");
+ dbdb = NULL;
+ }
+ }
+
+/* Allocate a new data block if the database lookup failed
+or the Bloom filter passed its age limit. */
+
+if (!dbdb)
+ {
+ if (!unique)
+ {
+ /* No Bloom filter. This basic ratelimit block is initialized below. */
+ HDEBUG(D_acl) debug_printf_indent("ratelimit creating new rate data block\n");
+ dbdb_size = sizeof(*dbd);
+ dbdb = store_get(dbdb_size, FALSE); /* not tainted */
+ }
+ else
+ {
+ int extra;
+ HDEBUG(D_acl) debug_printf_indent("ratelimit creating new Bloom filter\n");
+
+ /* See the long comment below for an explanation of the magic number 2.
+ The filter has a minimum size in case the rate limit is very small;
+ this is determined by the definition of dbdata_ratelimit_unique. */
+
+ extra = (int)limit * 2 - sizeof(dbdb->bloom);
+ if (extra < 0) extra = 0;
+ dbdb_size = sizeof(*dbdb) + extra;
+ dbdb = store_get(dbdb_size, FALSE); /* not tainted */
+ dbdb->bloom_epoch = tv.tv_sec;
+ dbdb->bloom_size = sizeof(dbdb->bloom) + extra;
+ memset(dbdb->bloom, 0, dbdb->bloom_size);
+
+ /* Preserve any basic ratelimit data (which is our longer-term memory)
+ by copying it from the discarded block. */
+
+ if (dbd)
+ {
+ dbdb->dbd = *dbd;
+ dbd = &dbdb->dbd;
+ }
+ }
+ }
+
+/* If we are counting unique events, find out if this event is new or not.
+If the client repeats the event during the current period then it should be
+counted. We skip this code in readonly mode for efficiency, because any
+changes to the filter will be discarded and because count is already set to
+zero. */
+
+if (unique && !readonly)
+ {
+ /* We identify unique events using a Bloom filter. (You can find my
+ notes on Bloom filters at http://fanf.livejournal.com/81696.html)
+ With the per_addr option, an "event" is a recipient address, though the
+ user can use the unique option to define their own events. We only count
+ an event if we have not seen it before.
+
+ We size the filter according to the rate limit, which (in leaky mode)
+ is the limit on the population of the filter. We allow 16 bits of space
+ per entry (see the construction code above) and we set (up to) 8 of them
+ when inserting an element (see the loop below). The probability of a false
+ positive (an event we have not seen before but which we fail to count) is
+
+ size = limit * 16
+ numhash = 8
+ allzero = exp(-numhash * pop / size)
+ = exp(-0.5 * pop / limit)
+ fpr = pow(1 - allzero, numhash)
+
+ For senders at the limit the fpr is 0.06% or 1 in 1700
+ and for senders at half the limit it is 0.0006% or 1 in 170000
+
+ In strict mode the Bloom filter can fill up beyond the normal limit, in
+ which case the false positive rate will rise. This means that the
+ measured rate for very fast senders can bogusly drop off after a while.
+
+ At twice the limit, the fpr is 2.5% or 1 in 40
+ At four times the limit, it is 31% or 1 in 3.2
+
+ It takes ln(pop/limit) periods for an over-limit burst of pop events to
+ decay below the limit, and if this is more than one then the Bloom filter
+ will be discarded before the decay gets that far. The false positive rate
+ at this threshold is 9.3% or 1 in 10.7. */
+
+ BOOL seen;
+ unsigned n, hash, hinc;
+ uschar md5sum[16];
+ md5 md5info;
+
+ /* Instead of using eight independent hash values, we combine two values
+ using the formula h1 + n * h2. This does not harm the Bloom filter's
+ performance, and means the amount of hash we need is independent of the
+ number of bits we set in the filter. */
+
+ md5_start(&md5info);
+ md5_end(&md5info, unique, Ustrlen(unique), md5sum);
+ hash = md5sum[0] | md5sum[1] << 8 | md5sum[2] << 16 | md5sum[3] << 24;
+ hinc = md5sum[4] | md5sum[5] << 8 | md5sum[6] << 16 | md5sum[7] << 24;
+
+ /* Scan the bits corresponding to this event. A zero bit means we have
+ not seen it before. Ensure all bits are set to record this event. */
+
+ HDEBUG(D_acl) debug_printf_indent("ratelimit checking uniqueness of %s\n", unique);
+
+ seen = TRUE;
+ for (n = 0; n < 8; n++, hash += hinc)
+ {
+ int bit = 1 << (hash % 8);
+ int byte = (hash / 8) % dbdb->bloom_size;
+ if ((dbdb->bloom[byte] & bit) == 0)
+ {
+ dbdb->bloom[byte] |= bit;
+ seen = FALSE;
+ }
+ }
+
+ /* If this event has occurred before, do not count it. */
+
+ if (seen)
+ {
+ HDEBUG(D_acl) debug_printf_indent("ratelimit event found in Bloom filter\n");
+ count = 0.0;
+ }
+ else
+ HDEBUG(D_acl) debug_printf_indent("ratelimit event added to Bloom filter\n");
+ }
+
+/* If there was no previous ratelimit data block for this key, initialize
+the new one, otherwise update the block from the database. The initial rate
+is what would be computed by the code below for an infinite interval. */
+
+if (!dbd)
+ {
+ HDEBUG(D_acl) debug_printf_indent("ratelimit initializing new key's rate data\n");
+ dbd = &dbdb->dbd;
+ dbd->time_stamp = tv.tv_sec;
+ dbd->time_usec = tv.tv_usec;
+ dbd->rate = count;
+ }
+else
+ {
+ /* The smoothed rate is computed using an exponentially weighted moving
+ average adjusted for variable sampling intervals. The standard EWMA for
+ a fixed sampling interval is: f'(t) = (1 - a) * f(t) + a * f'(t - 1)
+ where f() is the measured value and f'() is the smoothed value.
+
+ Old data decays out of the smoothed value exponentially, such that data n
+ samples old is multiplied by a^n. The exponential decay time constant p
+ is defined such that data p samples old is multiplied by 1/e, which means
+ that a = exp(-1/p). We can maintain the same time constant for a variable
+ sampling interval i by using a = exp(-i/p).
+
+ The rate we are measuring is messages per period, suitable for directly
+ comparing with the limit. The average rate between now and the previous
+ message is period / interval, which we feed into the EWMA as the sample.
+
+ It turns out that the number of messages required for the smoothed rate
+ to reach the limit when they are sent in a burst is equal to the limit.
+ This can be seen by analysing the value of the smoothed rate after N
+ messages sent at even intervals. Let k = (1 - a) * p/i
+
+ rate_1 = (1 - a) * p/i + a * rate_0
+ = k + a * rate_0
+ rate_2 = k + a * rate_1
+ = k + a * k + a^2 * rate_0
+ rate_3 = k + a * k + a^2 * k + a^3 * rate_0
+ rate_N = rate_0 * a^N + k * SUM(x=0..N-1)(a^x)
+ = rate_0 * a^N + k * (1 - a^N) / (1 - a)
+ = rate_0 * a^N + p/i * (1 - a^N)
+
+ When N is large, a^N -> 0 so rate_N -> p/i as desired.
+
+ rate_N = p/i + (rate_0 - p/i) * a^N
+ a^N = (rate_N - p/i) / (rate_0 - p/i)
+ N * -i/p = log((rate_N - p/i) / (rate_0 - p/i))
+ N = p/i * log((rate_0 - p/i) / (rate_N - p/i))
+
+ Numerical analysis of the above equation, setting the computed rate to
+ increase from rate_0 = 0 to rate_N = limit, shows that for large sending
+ rates, p/i, the number of messages N = limit. So limit serves as both the
+ maximum rate measured in messages per period, and the maximum number of
+ messages that can be sent in a fast burst. */
+
+ double this_time = (double)tv.tv_sec
+ + (double)tv.tv_usec / 1000000.0;
+ double prev_time = (double)dbd->time_stamp
+ + (double)dbd->time_usec / 1000000.0;
+
+ /* We must avoid division by zero, and deal gracefully with the clock going
+ backwards. If we blunder ahead when time is in reverse then the computed
+ rate will be bogus. To be safe we clamp interval to a very small number. */
+
+ double interval = this_time - prev_time <= 0.0 ? 1e-9
+ : this_time - prev_time;
+
+ double i_over_p = interval / period;
+ double a = exp(-i_over_p);
+
+ /* Combine the instantaneous rate (period / interval) with the previous rate
+ using the smoothing factor a. In order to measure sized events, multiply the
+ instantaneous rate by the count of bytes or recipients etc. */
+
+ dbd->time_stamp = tv.tv_sec;
+ dbd->time_usec = tv.tv_usec;
+ dbd->rate = (1 - a) * count / i_over_p + a * dbd->rate;
+
+ /* When events are very widely spaced the computed rate tends towards zero.
+ Although this is accurate it turns out not to be useful for our purposes,
+ especially when the first event after a long silence is the start of a spam
+ run. A more useful model is that the rate for an isolated event should be the
+ size of the event per the period size, ignoring the lack of events outside
+ the current period and regardless of where the event falls in the period. So,
+ if the interval was so long that the calculated rate is unhelpfully small, we
+ re-initialize the rate. In the absence of higher-rate bursts, the condition
+ below is true if the interval is greater than the period. */
+
+ if (dbd->rate < count) dbd->rate = count;
+ }
+
+/* Clients sending at the limit are considered to be over the limit.
+This matters for edge cases such as a limit of zero, when the client
+should be completely blocked. */
+
+rc = dbd->rate < limit ? FAIL : OK;
+
+/* Update the state if the rate is low or if we are being strict. If we
+are in leaky mode and the sender's rate is too high, we do not update
+the recorded rate in order to avoid an over-aggressive sender's retry
+rate preventing them from getting any email through. If readonly is set,
+neither leaky nor strict are set, so we do not do any updates. */
+
+if ((rc == FAIL && leaky) || strict)
+ {
+ dbfn_write(dbm, key, dbdb, dbdb_size);
+ HDEBUG(D_acl) debug_printf_indent("ratelimit db updated\n");
+ }
+else
+ {
+ HDEBUG(D_acl) debug_printf_indent("ratelimit db not updated: %s\n",
+ readonly? "readonly mode" : "over the limit, but leaky");
+ }
+
+dbfn_close(dbm);
+
+/* Store the result in the tree for future reference. Take the taint status
+from the key for consistency even though it's unlikely we'll ever expand this. */
+
+t = store_get(sizeof(tree_node) + Ustrlen(key), is_tainted(key));
+t->data.ptr = dbd;
+Ustrcpy(t->name, key);
+(void)tree_insertnode(anchor, t);
+
+/* We create the formatted version of the sender's rate very late in
+order to ensure that it is done using the correct storage pool. */
+
+store_pool = old_pool;
+sender_rate = string_sprintf("%.1f", dbd->rate);
+
+HDEBUG(D_acl)
+ debug_printf_indent("ratelimit computed rate %s\n", sender_rate);
+
+return rc;
+}
+
+
+
+/*************************************************
+* The udpsend ACL modifier *
+*************************************************/
+
+/* Called by acl_check_condition() below.
+
+Arguments:
+ arg the option string for udpsend=
+ log_msgptr for error messages
+
+Returns: OK - Completed.
+ DEFER - Problem with DNS lookup.
+ ERROR - Syntax error in options.
+*/
+
+static int
+acl_udpsend(const uschar *arg, uschar **log_msgptr)
+{
+int sep = 0;
+uschar *hostname;
+uschar *portstr;
+uschar *portend;
+host_item *h;
+int portnum;
+int len;
+int r, s;
+uschar * errstr;
+
+hostname = string_nextinlist(&arg, &sep, NULL, 0);
+portstr = string_nextinlist(&arg, &sep, NULL, 0);
+
+if (!hostname)
+ {
+ *log_msgptr = US"missing destination host in \"udpsend\" modifier";
+ return ERROR;
+ }
+if (!portstr)
+ {
+ *log_msgptr = US"missing destination port in \"udpsend\" modifier";
+ return ERROR;
+ }
+if (!arg)
+ {
+ *log_msgptr = US"missing datagram payload in \"udpsend\" modifier";
+ return ERROR;
+ }
+portnum = Ustrtol(portstr, &portend, 10);
+if (*portend != '\0')
+ {
+ *log_msgptr = US"bad destination port in \"udpsend\" modifier";
+ return ERROR;
+ }
+
+/* Make a single-item host list. */
+h = store_get(sizeof(host_item), FALSE);
+memset(h, 0, sizeof(host_item));
+h->name = hostname;
+h->port = portnum;
+h->mx = MX_NONE;
+
+if (string_is_ip_address(hostname, NULL))
+ h->address = hostname, r = HOST_FOUND;
+else
+ r = host_find_byname(h, NULL, 0, NULL, FALSE);
+if (r == HOST_FIND_FAILED || r == HOST_FIND_AGAIN)
+ {
+ *log_msgptr = US"DNS lookup failed in \"udpsend\" modifier";
+ return DEFER;
+ }
+
+HDEBUG(D_acl)
+ debug_printf_indent("udpsend [%s]:%d %s\n", h->address, portnum, arg);
+
+/*XXX this could better use sendto */
+r = s = ip_connectedsocket(SOCK_DGRAM, h->address, portnum, portnum,
+ 1, NULL, &errstr, NULL);
+if (r < 0) goto defer;
+len = Ustrlen(arg);
+r = send(s, arg, len, 0);
+if (r < 0)
+ {
+ errstr = US strerror(errno);
+ close(s);
+ goto defer;
+ }
+close(s);
+if (r < len)
+ {
+ *log_msgptr =
+ string_sprintf("\"udpsend\" truncated from %d to %d octets", len, r);
+ return DEFER;
+ }
+
+HDEBUG(D_acl)
+ debug_printf_indent("udpsend %d bytes\n", r);
+
+return OK;
+
+defer:
+*log_msgptr = string_sprintf("\"udpsend\" failed: %s", errstr);
+return DEFER;
+}
+
+
+
+/*************************************************
+* Handle conditions/modifiers on an ACL item *
+*************************************************/
+
+/* Called from acl_check() below.
+
+Arguments:
+ verb ACL verb
+ cb ACL condition block - if NULL, result is OK
+ where where called from
+ addr the address being checked for RCPT, or NULL
+ level the nesting level
+ epp pointer to pass back TRUE if "endpass" encountered
+ (applies only to "accept" and "discard")
+ user_msgptr user message pointer
+ log_msgptr log message pointer
+ basic_errno pointer to where to put verify error
+
+Returns: OK - all conditions are met
+ DISCARD - an "acl" condition returned DISCARD - only allowed
+ for "accept" or "discard" verbs
+ FAIL - at least one condition fails
+ FAIL_DROP - an "acl" condition returned FAIL_DROP
+ DEFER - can't tell at the moment (typically, lookup defer,
+ but can be temporary callout problem)
+ ERROR - ERROR from nested ACL or expansion failure or other
+ error
+*/
+
+static int
+acl_check_condition(int verb, acl_condition_block *cb, int where,
+ address_item *addr, int level, BOOL *epp, uschar **user_msgptr,
+ uschar **log_msgptr, int *basic_errno)
+{
+uschar *user_message = NULL;
+uschar *log_message = NULL;
+int rc = OK;
+#ifdef WITH_CONTENT_SCAN
+int sep = -'/';
+#endif
+
+for (; cb; cb = cb->next)
+ {
+ const uschar *arg;
+ int control_type;
+
+ /* The message and log_message items set up messages to be used in
+ case of rejection. They are expanded later. */
+
+ if (cb->type == ACLC_MESSAGE)
+ {
+ HDEBUG(D_acl) debug_printf_indent(" message: %s\n", cb->arg);
+ user_message = cb->arg;
+ continue;
+ }
+
+ if (cb->type == ACLC_LOG_MESSAGE)
+ {
+ HDEBUG(D_acl) debug_printf_indent("l_message: %s\n", cb->arg);
+ log_message = cb->arg;
+ continue;
+ }
+
+ /* The endpass "condition" just sets a flag to show it occurred. This is
+ checked at compile time to be on an "accept" or "discard" item. */
+
+ if (cb->type == ACLC_ENDPASS)
+ {
+ *epp = TRUE;
+ continue;
+ }
+
+ /* For other conditions and modifiers, the argument is expanded now for some
+ of them, but not for all, because expansion happens down in some lower level
+ checking functions in some cases. */
+
+ if (!conditions[cb->type].expand_at_top)
+ arg = cb->arg;
+ else if (!(arg = expand_string(cb->arg)))
+ {
+ if (f.expand_string_forcedfail) continue;
+ *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s",
+ cb->arg, expand_string_message);
+ return f.search_find_defer ? DEFER : ERROR;
+ }
+
+ /* Show condition, and expanded condition if it's different */
+
+ HDEBUG(D_acl)
+ {
+ int lhswidth = 0;
+ debug_printf_indent("check %s%s %n",
+ (!conditions[cb->type].is_modifier && cb->u.negated)? "!":"",
+ conditions[cb->type].name, &lhswidth);
+
+ if (cb->type == ACLC_SET)
+ {
+#ifndef DISABLE_DKIM
+ if ( Ustrcmp(cb->u.varname, "dkim_verify_status") == 0
+ || Ustrcmp(cb->u.varname, "dkim_verify_reason") == 0)
+ {
+ debug_printf("%s ", cb->u.varname);
+ lhswidth += 19;
+ }
+ else
+#endif
+ {
+ debug_printf("acl_%s ", cb->u.varname);
+ lhswidth += 5 + Ustrlen(cb->u.varname);
+ }
+ }
+
+ debug_printf("= %s\n", cb->arg);
+
+ if (arg != cb->arg)
+ debug_printf("%.*s= %s\n", lhswidth,
+ US" ", CS arg);
+ }
+
+ /* Check that this condition makes sense at this time */
+
+ if ((conditions[cb->type].forbids & (1 << where)) != 0)
+ {
+ *log_msgptr = string_sprintf("cannot %s %s condition in %s ACL",
+ conditions[cb->type].is_modifier ? "use" : "test",
+ conditions[cb->type].name, acl_wherenames[where]);
+ return ERROR;
+ }
+
+ /* Run the appropriate test for each condition, or take the appropriate
+ action for the remaining modifiers. */
+
+ switch(cb->type)
+ {
+ case ACLC_ADD_HEADER:
+ setup_header(arg);
+ break;
+
+ /* A nested ACL that returns "discard" makes sense only for an "accept" or
+ "discard" verb. */
+
+ case ACLC_ACL:
+ rc = acl_check_wargs(where, addr, arg, user_msgptr, log_msgptr);
+ if (rc == DISCARD && verb != ACL_ACCEPT && verb != ACL_DISCARD)
+ {
+ *log_msgptr = string_sprintf("nested ACL returned \"discard\" for "
+ "\"%s\" command (only allowed with \"accept\" or \"discard\")",
+ verbs[verb]);
+ return ERROR;
+ }
+ break;
+
+ case ACLC_AUTHENTICATED:
+ rc = sender_host_authenticated ? match_isinlist(sender_host_authenticated,
+ &arg, 0, NULL, NULL, MCL_STRING, TRUE, NULL) : FAIL;
+ break;
+
+ #ifdef EXPERIMENTAL_BRIGHTMAIL
+ case ACLC_BMI_OPTIN:
+ {
+ int old_pool = store_pool;
+ store_pool = POOL_PERM;
+ bmi_current_optin = string_copy(arg);
+ store_pool = old_pool;
+ }
+ break;
+ #endif
+
+ case ACLC_CONDITION:
+ /* The true/false parsing here should be kept in sync with that used in
+ expand.c when dealing with ECOND_BOOL so that we don't have too many
+ different definitions of what can be a boolean. */
+ if (*arg == '-'
+ ? Ustrspn(arg+1, "0123456789") == Ustrlen(arg+1) /* Negative number */
+ : Ustrspn(arg, "0123456789") == Ustrlen(arg)) /* Digits, or empty */
+ rc = (Uatoi(arg) == 0)? FAIL : OK;
+ else
+ rc = (strcmpic(arg, US"no") == 0 ||
+ strcmpic(arg, US"false") == 0)? FAIL :
+ (strcmpic(arg, US"yes") == 0 ||
+ strcmpic(arg, US"true") == 0)? OK : DEFER;
+ if (rc == DEFER)
+ *log_msgptr = string_sprintf("invalid \"condition\" value \"%s\"", arg);
+ break;
+
+ case ACLC_CONTINUE: /* Always succeeds */
+ break;
+
+ case ACLC_CONTROL:
+ {
+ const uschar *p = NULL;
+ control_type = decode_control(arg, &p, where, log_msgptr);
+
+ /* Check if this control makes sense at this time */
+
+ if (controls_list[control_type].forbids & (1 << where))
+ {
+ *log_msgptr = string_sprintf("cannot use \"control=%s\" in %s ACL",
+ controls_list[control_type].name, acl_wherenames[where]);
+ return ERROR;
+ }
+
+ switch(control_type)
+ {
+ case CONTROL_AUTH_UNADVERTISED:
+ f.allow_auth_unadvertised = TRUE;
+ break;
+
+#ifdef EXPERIMENTAL_BRIGHTMAIL
+ case CONTROL_BMI_RUN:
+ bmi_run = 1;
+ break;
+#endif
+
+#ifndef DISABLE_DKIM
+ case CONTROL_DKIM_VERIFY:
+ f.dkim_disable_verify = TRUE;
+# ifdef SUPPORT_DMARC
+ /* Since DKIM was blocked, skip DMARC too */
+ f.dmarc_disable_verify = TRUE;
+ f.dmarc_enable_forensic = FALSE;
+# endif
+ break;
+#endif
+
+#ifdef SUPPORT_DMARC
+ case CONTROL_DMARC_VERIFY:
+ f.dmarc_disable_verify = TRUE;
+ break;
+
+ case CONTROL_DMARC_FORENSIC:
+ f.dmarc_enable_forensic = TRUE;
+ break;
+#endif
+
+ case CONTROL_DSCP:
+ if (*p == '/')
+ {
+ int fd, af, level, optname, value;
+ /* If we are acting on stdin, the setsockopt may fail if stdin is not
+ a socket; we can accept that, we'll just debug-log failures anyway. */
+ fd = fileno(smtp_in);
+ if ((af = ip_get_address_family(fd)) < 0)
+ {
+ HDEBUG(D_acl)
+ debug_printf_indent("smtp input is probably not a socket [%s], not setting DSCP\n",
+ strerror(errno));
+ break;
+ }
+ if (dscp_lookup(p+1, af, &level, &optname, &value))
+ if (setsockopt(fd, level, optname, &value, sizeof(value)) < 0)
+ {
+ HDEBUG(D_acl) debug_printf_indent("failed to set input DSCP[%s]: %s\n",
+ p+1, strerror(errno));
+ }
+ else
+ {
+ HDEBUG(D_acl) debug_printf_indent("set input DSCP to \"%s\"\n", p+1);
+ }
+ else
+ {
+ *log_msgptr = string_sprintf("unrecognised DSCP value in \"control=%s\"", arg);
+ return ERROR;
+ }
+ }
+ else
+ {
+ *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
+ return ERROR;
+ }
+ break;
+
+ case CONTROL_ERROR:
+ return ERROR;
+
+ case CONTROL_CASEFUL_LOCAL_PART:
+ deliver_localpart = addr->cc_local_part;
+ break;
+
+ case CONTROL_CASELOWER_LOCAL_PART:
+ deliver_localpart = addr->lc_local_part;
+ break;
+
+ case CONTROL_ENFORCE_SYNC:
+ smtp_enforce_sync = TRUE;
+ break;
+
+ case CONTROL_NO_ENFORCE_SYNC:
+ smtp_enforce_sync = FALSE;
+ break;
+
+#ifdef WITH_CONTENT_SCAN
+ case CONTROL_NO_MBOX_UNSPOOL:
+ f.no_mbox_unspool = TRUE;
+ break;
+#endif
+
+ case CONTROL_NO_MULTILINE:
+ f.no_multiline_responses = TRUE;
+ break;
+
+ case CONTROL_NO_PIPELINING:
+ f.pipelining_enable = FALSE;
+ break;
+
+ case CONTROL_NO_DELAY_FLUSH:
+ f.disable_delay_flush = TRUE;
+ break;
+
+ case CONTROL_NO_CALLOUT_FLUSH:
+ f.disable_callout_flush = TRUE;
+ break;
+
+ case CONTROL_FAKEREJECT:
+ cancel_cutthrough_connection(TRUE, US"fakereject");
+ case CONTROL_FAKEDEFER:
+ fake_response = (control_type == CONTROL_FAKEDEFER) ? DEFER : FAIL;
+ if (*p == '/')
+ {
+ const uschar *pp = p + 1;
+ while (*pp) pp++;
+ fake_response_text = expand_string(string_copyn(p+1, pp-p-1));
+ p = pp;
+ }
+ else /* Explicitly reset to default string */
+ fake_response_text = US"Your message has been rejected but is being kept for evaluation.\nIf it was a legitimate message, it may still be delivered to the target recipient(s).";
+ break;
+
+ case CONTROL_FREEZE:
+ f.deliver_freeze = TRUE;
+ deliver_frozen_at = time(NULL);
+ freeze_tell = freeze_tell_config; /* Reset to configured value */
+ if (Ustrncmp(p, "/no_tell", 8) == 0)
+ {
+ p += 8;
+ freeze_tell = NULL;
+ }
+ if (*p)
+ {
+ *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
+ return ERROR;
+ }
+ cancel_cutthrough_connection(TRUE, US"item frozen");
+ break;
+
+ case CONTROL_QUEUE:
+ f.queue_only_policy = TRUE;
+ if (Ustrcmp(p, "_only") == 0)
+ p += 5;
+ else while (*p == '/')
+ if (Ustrncmp(p, "/only", 5) == 0)
+ { p += 5; f.queue_smtp = FALSE; }
+ else if (Ustrncmp(p, "/first_pass_route", 17) == 0)
+ { p += 17; f.queue_smtp = TRUE; }
+ else
+ break;
+ cancel_cutthrough_connection(TRUE, US"queueing forced");
+ break;
+
+ case CONTROL_SUBMISSION:
+ originator_name = US"";
+ f.submission_mode = TRUE;
+ while (*p == '/')
+ {
+ if (Ustrncmp(p, "/sender_retain", 14) == 0)
+ {
+ p += 14;
+ f.active_local_sender_retain = TRUE;
+ f.active_local_from_check = FALSE;
+ }
+ else if (Ustrncmp(p, "/domain=", 8) == 0)
+ {
+ const uschar *pp = p + 8;
+ while (*pp && *pp != '/') pp++;
+ submission_domain = string_copyn(p+8, pp-p-8);
+ p = pp;
+ }
+ /* The name= option must be last, because it swallows the rest of
+ the string. */
+ else if (Ustrncmp(p, "/name=", 6) == 0)
+ {
+ const uschar *pp = p + 6;
+ while (*pp) pp++;
+ submission_name = parse_fix_phrase(p+6, pp-p-6);
+ p = pp;
+ }
+ else break;
+ }
+ if (*p)
+ {
+ *log_msgptr = string_sprintf("syntax error in \"control=%s\"", arg);
+ return ERROR;
+ }
+ break;
+
+ case CONTROL_DEBUG:
+ {
+ uschar * debug_tag = NULL;
+ uschar * debug_opts = NULL;
+ BOOL kill = FALSE;
+
+ while (*p == '/')
+ {
+ const uschar * pp = p+1;
+ if (Ustrncmp(pp, "tag=", 4) == 0)
+ {
+ for (pp += 4; *pp && *pp != '/';) pp++;
+ debug_tag = string_copyn(p+5, pp-p-5);
+ }
+ else if (Ustrncmp(pp, "opts=", 5) == 0)
+ {
+ for (pp += 5; *pp && *pp != '/';) pp++;
+ debug_opts = string_copyn(p+6, pp-p-6);
+ }
+ else if (Ustrncmp(pp, "kill", 4) == 0)
+ {
+ for (pp += 4; *pp && *pp != '/';) pp++;
+ kill = TRUE;
+ }
+ else
+ while (*pp && *pp != '/') pp++;
+ p = pp;
+ }
+
+ if (kill)
+ debug_logging_stop();
+ else
+ debug_logging_activate(debug_tag, debug_opts);
+ break;
+ }
+
+ case CONTROL_SUPPRESS_LOCAL_FIXUPS:
+ f.suppress_local_fixups = TRUE;
+ break;
+
+ case CONTROL_CUTTHROUGH_DELIVERY:
+ {
+ uschar * ignored = NULL;
+#ifndef DISABLE_PRDR
+ if (prdr_requested)
+#else
+ if (0)
+#endif
+ /* Too hard to think about for now. We might in future cutthrough
+ the case where both sides handle prdr and this-node prdr acl
+ is "accept" */
+ ignored = US"PRDR active";
+ else if (f.deliver_freeze)
+ ignored = US"frozen";
+ else if (f.queue_only_policy)
+ ignored = US"queue-only";
+ else if (fake_response == FAIL)
+ ignored = US"fakereject";
+ else if (rcpt_count != 1)
+ ignored = US"nonfirst rcpt";
+ else if (cutthrough.delivery)
+ ignored = US"repeated";
+ else if (cutthrough.callout_hold_only)
+ {
+ DEBUG(D_acl)
+ debug_printf_indent(" cutthrough request upgrades callout hold\n");
+ cutthrough.callout_hold_only = FALSE;
+ cutthrough.delivery = TRUE; /* control accepted */
+ }
+ else
+ {
+ cutthrough.delivery = TRUE; /* control accepted */
+ while (*p == '/')
+ {
+ const uschar * pp = p+1;
+ if (Ustrncmp(pp, "defer=", 6) == 0)
+ {
+ pp += 6;
+ if (Ustrncmp(pp, "pass", 4) == 0) cutthrough.defer_pass = TRUE;
+ /* else if (Ustrncmp(pp, "spool") == 0) ; default */
+ }
+ else
+ while (*pp && *pp != '/') pp++;
+ p = pp;
+ }
+ }
+
+ DEBUG(D_acl) if (ignored)
+ debug_printf(" cutthrough request ignored on %s item\n", ignored);
+ }
+ break;
+
+#ifdef SUPPORT_I18N
+ case CONTROL_UTF8_DOWNCONVERT:
+ if (*p == '/')
+ {
+ if (p[1] == '1')
+ {
+ message_utf8_downconvert = 1;
+ addr->prop.utf8_downcvt = TRUE;
+ addr->prop.utf8_downcvt_maybe = FALSE;
+ p += 2;
+ break;
+ }
+ if (p[1] == '0')
+ {
+ message_utf8_downconvert = 0;
+ addr->prop.utf8_downcvt = FALSE;
+ addr->prop.utf8_downcvt_maybe = FALSE;
+ p += 2;
+ break;
+ }
+ if (p[1] == '-' && p[2] == '1')
+ {
+ message_utf8_downconvert = -1;
+ addr->prop.utf8_downcvt = FALSE;
+ addr->prop.utf8_downcvt_maybe = TRUE;
+ p += 3;
+ break;
+ }
+ *log_msgptr = US"bad option value for control=utf8_downconvert";
+ }
+ else
+ {
+ message_utf8_downconvert = 1;
+ addr->prop.utf8_downcvt = TRUE;
+ addr->prop.utf8_downcvt_maybe = FALSE;
+ break;
+ }
+ return ERROR;
+#endif
+
+ }
+ break;
+ }
+
+ #ifdef EXPERIMENTAL_DCC
+ case ACLC_DCC:
+ {
+ /* Separate the regular expression and any optional parameters. */
+ const uschar * list = arg;
+ uschar *ss = string_nextinlist(&list, &sep, NULL, 0);
+ /* Run the dcc backend. */
+ rc = dcc_process(&ss);
+ /* Modify return code based upon the existence of options. */
+ while ((ss = string_nextinlist(&list, &sep, NULL, 0)))
+ if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
+ rc = FAIL; /* FAIL so that the message is passed to the next ACL */
+ }
+ break;
+ #endif
+
+ #ifdef WITH_CONTENT_SCAN
+ case ACLC_DECODE:
+ rc = mime_decode(&arg);
+ break;
+ #endif
+
+ case ACLC_DELAY:
+ {
+ int delay = readconf_readtime(arg, 0, FALSE);
+ if (delay < 0)
+ {
+ *log_msgptr = string_sprintf("syntax error in argument for \"delay\" "
+ "modifier: \"%s\" is not a time value", arg);
+ return ERROR;
+ }
+ else
+ {
+ HDEBUG(D_acl) debug_printf_indent("delay modifier requests %d-second delay\n",
+ delay);
+ if (host_checking)
+ {
+ HDEBUG(D_acl)
+ debug_printf_indent("delay skipped in -bh checking mode\n");
+ }
+
+ /* NOTE 1: Remember that we may be
+ dealing with stdin/stdout here, in addition to TCP/IP connections.
+ Also, delays may be specified for non-SMTP input, where smtp_out and
+ smtp_in will be NULL. Whatever is done must work in all cases.
+
+ NOTE 2: The added feature of flushing the output before a delay must
+ apply only to SMTP input. Hence the test for smtp_out being non-NULL.
+ */
+
+ else
+ {
+ if (smtp_out && !f.disable_delay_flush)
+ mac_smtp_fflush();
+
+#if !defined(NO_POLL_H) && defined (POLLRDHUP)
+ {
+ struct pollfd p;
+ nfds_t n = 0;
+ if (smtp_out)
+ {
+ p.fd = fileno(smtp_out);
+ p.events = POLLRDHUP;
+ n = 1;
+ }
+ if (poll(&p, n, delay*1000) > 0)
+ HDEBUG(D_acl) debug_printf_indent("delay cancelled by peer close\n");
+ }
+#else
+ /* Lacking POLLRDHUP it appears to be impossible to detect that a
+ TCP/IP connection has gone away without reading from it. This means
+ that we cannot shorten the delay below if the client goes away,
+ because we cannot discover that the client has closed its end of the
+ connection. (The connection is actually in a half-closed state,
+ waiting for the server to close its end.) It would be nice to be able
+ to detect this state, so that the Exim process is not held up
+ unnecessarily. However, it seems that we can't. The poll() function
+ does not do the right thing, and in any case it is not always
+ available. */
+
+ while (delay > 0) delay = sleep(delay);
+#endif
+ }
+ }
+ }
+ break;
+
+ #ifndef DISABLE_DKIM
+ case ACLC_DKIM_SIGNER:
+ if (dkim_cur_signer)
+ rc = match_isinlist(dkim_cur_signer,
+ &arg, 0, NULL, NULL, MCL_STRING, TRUE, NULL);
+ else
+ rc = FAIL;
+ break;
+
+ case ACLC_DKIM_STATUS:
+ rc = match_isinlist(dkim_verify_status,
+ &arg, 0, NULL, NULL, MCL_STRING, TRUE, NULL);
+ break;
+ #endif
+
+#ifdef SUPPORT_DMARC
+ case ACLC_DMARC_STATUS:
+ if (!f.dmarc_has_been_checked)
+ dmarc_process();
+ f.dmarc_has_been_checked = TRUE;
+ /* used long way of dmarc_exim_expand_query() in case we need more
+ * view into the process in the future. */
+ rc = match_isinlist(dmarc_exim_expand_query(DMARC_VERIFY_STATUS),
+ &arg, 0, NULL, NULL, MCL_STRING, TRUE, NULL);
+ break;
+#endif
+
+ case ACLC_DNSLISTS:
+ rc = verify_check_dnsbl(where, &arg, log_msgptr);
+ break;
+
+ case ACLC_DOMAINS:
+ rc = match_isinlist(addr->domain, &arg, 0, &domainlist_anchor,
+ addr->domain_cache, MCL_DOMAIN, TRUE, CUSS &deliver_domain_data);
+ break;
+
+ /* The value in tls_cipher is the full cipher name, for example,
+ TLSv1:DES-CBC3-SHA:168, whereas the values to test for are just the
+ cipher names such as DES-CBC3-SHA. But program defensively. We don't know
+ what may in practice come out of the SSL library - which at the time of
+ writing is poorly documented. */
+
+ case ACLC_ENCRYPTED:
+ if (tls_in.cipher == NULL) rc = FAIL; else
+ {
+ uschar *endcipher = NULL;
+ uschar *cipher = Ustrchr(tls_in.cipher, ':');
+ if (!cipher) cipher = tls_in.cipher; else
+ {
+ endcipher = Ustrchr(++cipher, ':');
+ if (endcipher) *endcipher = 0;
+ }
+ rc = match_isinlist(cipher, &arg, 0, NULL, NULL, MCL_STRING, TRUE, NULL);
+ if (endcipher) *endcipher = ':';
+ }
+ break;
+
+ /* Use verify_check_this_host() instead of verify_check_host() so that
+ we can pass over &host_data to catch any looked up data. Once it has been
+ set, it retains its value so that it's still there if another ACL verb
+ comes through here and uses the cache. However, we must put it into
+ permanent store in case it is also expected to be used in a subsequent
+ message in the same SMTP connection. */
+
+ case ACLC_HOSTS:
+ rc = verify_check_this_host(&arg, sender_host_cache, NULL,
+ sender_host_address ? sender_host_address : US"", CUSS &host_data);
+ if (rc == DEFER) *log_msgptr = search_error_message;
+ if (host_data) host_data = string_copy_perm(host_data, TRUE);
+ break;
+
+ case ACLC_LOCAL_PARTS:
+ rc = match_isinlist(addr->cc_local_part, &arg, 0,
+ &localpartlist_anchor, addr->localpart_cache, MCL_LOCALPART, TRUE,
+ CUSS &deliver_localpart_data);
+ break;
+
+ case ACLC_LOG_REJECT_TARGET:
+ {
+ int logbits = 0;
+ int sep = 0;
+ const uschar *s = arg;
+ uschar * ss;
+ while ((ss = string_nextinlist(&s, &sep, NULL, 0)))
+ {
+ if (Ustrcmp(ss, "main") == 0) logbits |= LOG_MAIN;
+ else if (Ustrcmp(ss, "panic") == 0) logbits |= LOG_PANIC;
+ else if (Ustrcmp(ss, "reject") == 0) logbits |= LOG_REJECT;
+ else
+ {
+ logbits |= LOG_MAIN|LOG_REJECT;
+ log_write(0, LOG_MAIN|LOG_PANIC, "unknown log name \"%s\" in "
+ "\"log_reject_target\" in %s ACL", ss, acl_wherenames[where]);
+ }
+ }
+ log_reject_target = logbits;
+ }
+ break;
+
+ case ACLC_LOGWRITE:
+ {
+ int logbits = 0;
+ const uschar *s = arg;
+ if (*s == ':')
+ {
+ s++;
+ while (*s != ':')
+ {
+ if (Ustrncmp(s, "main", 4) == 0)
+ { logbits |= LOG_MAIN; s += 4; }
+ else if (Ustrncmp(s, "panic", 5) == 0)
+ { logbits |= LOG_PANIC; s += 5; }
+ else if (Ustrncmp(s, "reject", 6) == 0)
+ { logbits |= LOG_REJECT; s += 6; }
+ else
+ {
+ logbits = LOG_MAIN|LOG_PANIC;
+ s = string_sprintf(":unknown log name in \"%s\" in "
+ "\"logwrite\" in %s ACL", arg, acl_wherenames[where]);
+ }
+ if (*s == ',') s++;
+ }
+ s++;
+ }
+ while (isspace(*s)) s++;
+
+ if (logbits == 0) logbits = LOG_MAIN;
+ log_write(0, logbits, "%s", string_printing(s));
+ }
+ break;
+
+ #ifdef WITH_CONTENT_SCAN
+ case ACLC_MALWARE: /* Run the malware backend. */
+ {
+ /* Separate the regular expression and any optional parameters. */
+ const uschar * list = arg;
+ uschar * ss = string_nextinlist(&list, &sep, NULL, 0);
+ uschar * opt;
+ BOOL defer_ok = FALSE;
+ int timeout = 0;
+
+ while ((opt = string_nextinlist(&list, &sep, NULL, 0)))
+ if (strcmpic(opt, US"defer_ok") == 0)
+ defer_ok = TRUE;
+ else if ( strncmpic(opt, US"tmo=", 4) == 0
+ && (timeout = readconf_readtime(opt+4, '\0', FALSE)) < 0
+ )
+ {
+ *log_msgptr = string_sprintf("bad timeout value in '%s'", opt);
+ return ERROR;
+ }
+
+ rc = malware(ss, timeout);
+ if (rc == DEFER && defer_ok)
+ rc = FAIL; /* FAIL so that the message is passed to the next ACL */
+ }
+ break;
+
+ case ACLC_MIME_REGEX:
+ rc = mime_regex(&arg);
+ break;
+ #endif
+
+ case ACLC_QUEUE:
+ if (is_tainted(arg))
+ {
+ *log_msgptr = string_sprintf("Tainted name '%s' for queue not permitted",
+ arg);
+ return ERROR;
+ }
+ if (Ustrchr(arg, '/'))
+ {
+ *log_msgptr = string_sprintf(
+ "Directory separator not permitted in queue name: '%s'", arg);
+ return ERROR;
+ }
+ queue_name = string_copy_perm(arg, FALSE);
+ break;
+
+ case ACLC_RATELIMIT:
+ rc = acl_ratelimit(arg, where, log_msgptr);
+ break;
+
+ case ACLC_RECIPIENTS:
+ rc = match_address_list(CUS addr->address, TRUE, TRUE, &arg, NULL, -1, 0,
+ CUSS &recipient_data);
+ break;
+
+ #ifdef WITH_CONTENT_SCAN
+ case ACLC_REGEX:
+ rc = regex(&arg);
+ break;
+ #endif
+
+ case ACLC_REMOVE_HEADER:
+ setup_remove_header(arg);
+ break;
+
+ case ACLC_SENDER_DOMAINS:
+ {
+ uschar *sdomain;
+ sdomain = Ustrrchr(sender_address, '@');
+ sdomain = sdomain ? sdomain + 1 : US"";
+ rc = match_isinlist(sdomain, &arg, 0, &domainlist_anchor,
+ sender_domain_cache, MCL_DOMAIN, TRUE, NULL);
+ }
+ break;
+
+ case ACLC_SENDERS:
+ rc = match_address_list(CUS sender_address, TRUE, TRUE, &arg,
+ sender_address_cache, -1, 0, CUSS &sender_data);
+ break;
+
+ /* Connection variables must persist forever; message variables not */
+
+ case ACLC_SET:
+ {
+ int old_pool = store_pool;
+ if ( cb->u.varname[0] != 'm'
+#ifndef DISABLE_EVENT
+ || event_name /* An event is being delivered */
+#endif
+ )
+ store_pool = POOL_PERM;
+#ifndef DISABLE_DKIM /* Overwriteable dkim result variables */
+ if (Ustrcmp(cb->u.varname, "dkim_verify_status") == 0)
+ dkim_verify_status = string_copy(arg);
+ else if (Ustrcmp(cb->u.varname, "dkim_verify_reason") == 0)
+ dkim_verify_reason = string_copy(arg);
+ else
+#endif
+ acl_var_create(cb->u.varname)->data.ptr = string_copy(arg);
+ store_pool = old_pool;
+ }
+ break;
+
+#ifdef WITH_CONTENT_SCAN
+ case ACLC_SPAM:
+ {
+ /* Separate the regular expression and any optional parameters. */
+ const uschar * list = arg;
+ uschar *ss = string_nextinlist(&list, &sep, NULL, 0);
+
+ rc = spam(CUSS &ss);
+ /* Modify return code based upon the existence of options. */
+ while ((ss = string_nextinlist(&list, &sep, NULL, 0)))
+ if (strcmpic(ss, US"defer_ok") == 0 && rc == DEFER)
+ rc = FAIL; /* FAIL so that the message is passed to the next ACL */
+ }
+ break;
+#endif
+
+#ifdef SUPPORT_SPF
+ case ACLC_SPF:
+ rc = spf_process(&arg, sender_address, SPF_PROCESS_NORMAL);
+ break;
+ case ACLC_SPF_GUESS:
+ rc = spf_process(&arg, sender_address, SPF_PROCESS_GUESS);
+ break;
+#endif
+
+ case ACLC_UDPSEND:
+ rc = acl_udpsend(arg, log_msgptr);
+ break;
+
+ /* If the verb is WARN, discard any user message from verification, because
+ such messages are SMTP responses, not header additions. The latter come
+ only from explicit "message" modifiers. However, put the user message into
+ $acl_verify_message so it can be used in subsequent conditions or modifiers
+ (until something changes it). */
+
+ case ACLC_VERIFY:
+ rc = acl_verify(where, addr, arg, user_msgptr, log_msgptr, basic_errno);
+ if (*user_msgptr)
+ acl_verify_message = *user_msgptr;
+ if (verb == ACL_WARN) *user_msgptr = NULL;
+ break;
+
+ default:
+ log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal ACL error: unknown "
+ "condition %d", cb->type);
+ break;
+ }
+
+ /* If a condition was negated, invert OK/FAIL. */
+
+ if (!conditions[cb->type].is_modifier && cb->u.negated)
+ if (rc == OK) rc = FAIL;
+ else if (rc == FAIL || rc == FAIL_DROP) rc = OK;
+
+ if (rc != OK) break; /* Conditions loop */
+ }
+
+
+/* If the result is the one for which "message" and/or "log_message" are used,
+handle the values of these modifiers. If there isn't a log message set, we make
+it the same as the user message.
+
+"message" is a user message that will be included in an SMTP response. Unless
+it is empty, it overrides any previously set user message.
+
+"log_message" is a non-user message, and it adds to any existing non-user
+message that is already set.
+
+Most verbs have but a single return for which the messages are relevant, but
+for "discard", it's useful to have the log message both when it succeeds and
+when it fails. For "accept", the message is used in the OK case if there is no
+"endpass", but (for backwards compatibility) in the FAIL case if "endpass" is
+present. */
+
+if (*epp && rc == OK) user_message = NULL;
+
+if ((BIT(rc) & msgcond[verb]) != 0)
+ {
+ uschar *expmessage;
+ uschar *old_user_msgptr = *user_msgptr;
+ uschar *old_log_msgptr = (*log_msgptr != NULL)? *log_msgptr : old_user_msgptr;
+
+ /* If the verb is "warn", messages generated by conditions (verification or
+ nested ACLs) are always discarded. This also happens for acceptance verbs
+ when they actually do accept. Only messages specified at this level are used.
+ However, the value of an existing message is available in $acl_verify_message
+ during expansions. */
+
+ if (verb == ACL_WARN ||
+ (rc == OK && (verb == ACL_ACCEPT || verb == ACL_DISCARD)))
+ *log_msgptr = *user_msgptr = NULL;
+
+ if (user_message)
+ {
+ acl_verify_message = old_user_msgptr;
+ expmessage = expand_string(user_message);
+ if (!expmessage)
+ {
+ if (!f.expand_string_forcedfail)
+ log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand ACL message \"%s\": %s",
+ user_message, expand_string_message);
+ }
+ else if (expmessage[0] != 0) *user_msgptr = expmessage;
+ }
+
+ if (log_message)
+ {
+ acl_verify_message = old_log_msgptr;
+ expmessage = expand_string(log_message);
+ if (!expmessage)
+ {
+ if (!f.expand_string_forcedfail)
+ log_write(0, LOG_MAIN|LOG_PANIC, "failed to expand ACL message \"%s\": %s",
+ log_message, expand_string_message);
+ }
+ else if (expmessage[0] != 0)
+ {
+ *log_msgptr = (*log_msgptr == NULL)? expmessage :
+ string_sprintf("%s: %s", expmessage, *log_msgptr);
+ }
+ }
+
+ /* If no log message, default it to the user message */
+
+ if (!*log_msgptr) *log_msgptr = *user_msgptr;
+ }
+
+acl_verify_message = NULL;
+return rc;
+}
+
+
+
+
+
+/*************************************************
+* Get line from a literal ACL *
+*************************************************/
+
+/* This function is passed to acl_read() in order to extract individual lines
+of a literal ACL, which we access via static pointers. We can destroy the
+contents because this is called only once (the compiled ACL is remembered).
+
+This code is intended to treat the data in the same way as lines in the main
+Exim configuration file. That is:
+
+ . Leading spaces are ignored.
+
+ . A \ at the end of a line is a continuation - trailing spaces after the \
+ are permitted (this is because I don't believe in making invisible things
+ significant). Leading spaces on the continued part of a line are ignored.
+
+ . Physical lines starting (significantly) with # are totally ignored, and
+ may appear within a sequence of backslash-continued lines.
+
+ . Blank lines are ignored, but will end a sequence of continuations.
+
+Arguments: none
+Returns: a pointer to the next line
+*/
+
+
+static uschar *acl_text; /* Current pointer in the text */
+static uschar *acl_text_end; /* Points one past the terminating '0' */
+
+
+static uschar *
+acl_getline(void)
+{
+uschar *yield;
+
+/* This loop handles leading blank lines and comments. */
+
+for(;;)
+ {
+ Uskip_whitespace(&acl_text); /* Leading spaces/empty lines */
+ if (!*acl_text) return NULL; /* No more data */
+ yield = acl_text; /* Potential data line */
+
+ while (*acl_text && *acl_text != '\n') acl_text++;
+
+ /* If we hit the end before a newline, we have the whole logical line. If
+ it's a comment, there's no more data to be given. Otherwise, yield it. */
+
+ if (!*acl_text) return *yield == '#' ? NULL : yield;
+
+ /* After reaching a newline, end this loop if the physical line does not
+ start with '#'. If it does, it's a comment, and the loop continues. */
+
+ if (*yield != '#') break;
+ }
+
+/* This loop handles continuations. We know we have some real data, ending in
+newline. See if there is a continuation marker at the end (ignoring trailing
+white space). We know that *yield is not white space, so no need to test for
+cont > yield in the backwards scanning loop. */
+
+for(;;)
+ {
+ uschar *cont;
+ for (cont = acl_text - 1; isspace(*cont); cont--);
+
+ /* If no continuation follows, we are done. Mark the end of the line and
+ return it. */
+
+ if (*cont != '\\')
+ {
+ *acl_text++ = 0;
+ return yield;
+ }
+
+ /* We have encountered a continuation. Skip over whitespace at the start of
+ the next line, and indeed the whole of the next line or lines if they are
+ comment lines. */
+
+ for (;;)
+ {
+ while (*(++acl_text) == ' ' || *acl_text == '\t');
+ if (*acl_text != '#') break;
+ while (*(++acl_text) != 0 && *acl_text != '\n');
+ }
+
+ /* We have the start of a continuation line. Move all the rest of the data
+ to join onto the previous line, and then find its end. If the end is not a
+ newline, we are done. Otherwise loop to look for another continuation. */
+
+ memmove(cont, acl_text, acl_text_end - acl_text);
+ acl_text_end -= acl_text - cont;
+ acl_text = cont;
+ while (*acl_text != 0 && *acl_text != '\n') acl_text++;
+ if (*acl_text == 0) return yield;
+ }
+
+/* Control does not reach here */
+}
+
+
+
+
+
+/*************************************************
+* Check access using an ACL *
+*************************************************/
+
+/* This function is called from address_check. It may recurse via
+acl_check_condition() - hence the use of a level to stop looping. The ACL is
+passed as a string which is expanded. A forced failure implies no access check
+is required. If the result is a single word, it is taken as the name of an ACL
+which is sought in the global ACL tree. Otherwise, it is taken as literal ACL
+text, complete with newlines, and parsed as such. In both cases, the ACL check
+is then run. This function uses an auxiliary function for acl_read() to call
+for reading individual lines of a literal ACL. This is acl_getline(), which
+appears immediately above.
+
+Arguments:
+ where where called from
+ addr address item when called from RCPT; otherwise NULL
+ s the input string; NULL is the same as an empty ACL => DENY
+ user_msgptr where to put a user error (for SMTP response)
+ log_msgptr where to put a logging message (not for SMTP response)
+
+Returns: OK access is granted
+ DISCARD access is apparently granted...
+ FAIL access is denied
+ FAIL_DROP access is denied; drop the connection
+ DEFER can't tell at the moment
+ ERROR disaster
+*/
+
+static int
+acl_check_internal(int where, address_item *addr, uschar *s,
+ uschar **user_msgptr, uschar **log_msgptr)
+{
+int fd = -1;
+acl_block *acl = NULL;
+uschar *acl_name = US"inline ACL";
+uschar *ss;
+
+/* Catch configuration loops */
+
+if (acl_level > 20)
+ {
+ *log_msgptr = US"ACL nested too deep: possible loop";
+ return ERROR;
+ }
+
+if (!s)
+ {
+ HDEBUG(D_acl) debug_printf_indent("ACL is NULL: implicit DENY\n");
+ return FAIL;
+ }
+
+/* At top level, we expand the incoming string. At lower levels, it has already
+been expanded as part of condition processing. */
+
+if (acl_level == 0)
+ {
+ if (!(ss = expand_string(s)))
+ {
+ if (f.expand_string_forcedfail) return OK;
+ *log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s", s,
+ expand_string_message);
+ return ERROR;
+ }
+ }
+else ss = s;
+
+while (isspace(*ss)) ss++;
+
+/* If we can't find a named ACL, the default is to parse it as an inline one.
+(Unless it begins with a slash; non-existent files give rise to an error.) */
+
+acl_text = ss;
+
+/* Handle the case of a string that does not contain any spaces. Look for a
+named ACL among those read from the configuration, or a previously read file.
+It is possible that the pointer to the ACL is NULL if the configuration
+contains a name with no data. If not found, and the text begins with '/',
+read an ACL from a file, and save it so it can be re-used. */
+
+if (Ustrchr(ss, ' ') == NULL)
+ {
+ tree_node * t = tree_search(acl_anchor, ss);
+ if (t)
+ {
+ if (!(acl = (acl_block *)(t->data.ptr)))
+ {
+ HDEBUG(D_acl) debug_printf_indent("ACL \"%s\" is empty: implicit DENY\n", ss);
+ return FAIL;
+ }
+ acl_name = string_sprintf("ACL \"%s\"", ss);
+ HDEBUG(D_acl) debug_printf_indent("using ACL \"%s\"\n", ss);
+ }
+
+ else if (*ss == '/')
+ {
+ struct stat statbuf;
+ if (is_tainted(ss))
+ {
+ log_write(0, LOG_MAIN|LOG_PANIC,
+ "attempt to open tainted ACL file name \"%s\"", ss);
+ /* Avoid leaking info to an attacker */
+ *log_msgptr = US"internal configuration error";
+ return ERROR;
+ }
+ if ((fd = Uopen(ss, O_RDONLY, 0)) < 0)
+ {
+ *log_msgptr = string_sprintf("failed to open ACL file \"%s\": %s", ss,
+ strerror(errno));
+ return ERROR;
+ }
+ if (fstat(fd, &statbuf) != 0)
+ {
+ *log_msgptr = string_sprintf("failed to fstat ACL file \"%s\": %s", ss,
+ strerror(errno));
+ return ERROR;
+ }
+
+ /* If the string being used as a filename is tainted, so is the file content */
+ acl_text = store_get(statbuf.st_size + 1, is_tainted(ss));
+ acl_text_end = acl_text + statbuf.st_size + 1;
+
+ if (read(fd, acl_text, statbuf.st_size) != statbuf.st_size)
+ {
+ *log_msgptr = string_sprintf("failed to read ACL file \"%s\": %s",
+ ss, strerror(errno));
+ return ERROR;
+ }
+ acl_text[statbuf.st_size] = 0;
+ (void)close(fd);
+
+ acl_name = string_sprintf("ACL \"%s\"", ss);
+ HDEBUG(D_acl) debug_printf_indent("read ACL from file %s\n", ss);
+ }
+ }
+
+/* Parse an ACL that is still in text form. If it came from a file, remember it
+in the ACL tree, having read it into the POOL_PERM store pool so that it
+persists between multiple messages. */
+
+if (!acl)
+ {
+ int old_pool = store_pool;
+ if (fd >= 0) store_pool = POOL_PERM;
+ acl = acl_read(acl_getline, log_msgptr);
+ store_pool = old_pool;
+ if (!acl && *log_msgptr) return ERROR;
+ if (fd >= 0)
+ {
+ tree_node *t = store_get_perm(sizeof(tree_node) + Ustrlen(ss), is_tainted(ss));
+ Ustrcpy(t->name, ss);
+ t->data.ptr = acl;
+ (void)tree_insertnode(&acl_anchor, t);
+ }
+ }
+
+/* Now we have an ACL to use. It's possible it may be NULL. */
+
+while (acl)
+ {
+ int cond;
+ int basic_errno = 0;
+ BOOL endpass_seen = FALSE;
+ BOOL acl_quit_check = acl_level == 0
+ && (where == ACL_WHERE_QUIT || where == ACL_WHERE_NOTQUIT);
+
+ *log_msgptr = *user_msgptr = NULL;
+ f.acl_temp_details = FALSE;
+
+ HDEBUG(D_acl) debug_printf_indent("processing \"%s\" (%s %d)\n",
+ verbs[acl->verb], acl->srcfile, acl->srcline);
+
+ /* Clear out any search error message from a previous check before testing
+ this condition. */
+
+ search_error_message = NULL;
+ cond = acl_check_condition(acl->verb, acl->condition, where, addr, acl_level,
+ &endpass_seen, user_msgptr, log_msgptr, &basic_errno);
+
+ /* Handle special returns: DEFER causes a return except on a WARN verb;
+ ERROR always causes a return. */
+
+ switch (cond)
+ {
+ case DEFER:
+ HDEBUG(D_acl) debug_printf_indent("%s: condition test deferred in %s\n",
+ verbs[acl->verb], acl_name);
+ if (basic_errno != ERRNO_CALLOUTDEFER)
+ {
+ if (search_error_message != NULL && *search_error_message != 0)
+ *log_msgptr = search_error_message;
+ if (smtp_return_error_details) f.acl_temp_details = TRUE;
+ }
+ else
+ f.acl_temp_details = TRUE;
+ if (acl->verb != ACL_WARN) return DEFER;
+ break;
+
+ default: /* Paranoia */
+ case ERROR:
+ HDEBUG(D_acl) debug_printf_indent("%s: condition test error in %s\n",
+ verbs[acl->verb], acl_name);
+ return ERROR;
+
+ case OK:
+ HDEBUG(D_acl) debug_printf_indent("%s: condition test succeeded in %s\n",
+ verbs[acl->verb], acl_name);
+ break;
+
+ case FAIL:
+ HDEBUG(D_acl) debug_printf_indent("%s: condition test failed in %s\n",
+ verbs[acl->verb], acl_name);
+ break;
+
+ /* DISCARD and DROP can happen only from a nested ACL condition, and
+ DISCARD can happen only for an "accept" or "discard" verb. */
+
+ case DISCARD:
+ HDEBUG(D_acl) debug_printf_indent("%s: condition test yielded \"discard\" in %s\n",
+ verbs[acl->verb], acl_name);
+ break;
+
+ case FAIL_DROP:
+ HDEBUG(D_acl) debug_printf_indent("%s: condition test yielded \"drop\" in %s\n",
+ verbs[acl->verb], acl_name);
+ break;
+ }
+
+ /* At this point, cond for most verbs is either OK or FAIL or (as a result of
+ a nested ACL condition) FAIL_DROP. However, for WARN, cond may be DEFER, and
+ for ACCEPT and DISCARD, it may be DISCARD after a nested ACL call. */
+
+ switch(acl->verb)
+ {
+ case ACL_ACCEPT:
+ if (cond == OK || cond == DISCARD)
+ {
+ HDEBUG(D_acl) debug_printf_indent("end of %s: ACCEPT\n", acl_name);
+ return cond;
+ }
+ if (endpass_seen)
+ {
+ HDEBUG(D_acl) debug_printf_indent("accept: endpass encountered - denying access\n");
+ return cond;
+ }
+ break;
+
+ case ACL_DEFER:
+ if (cond == OK)
+ {
+ HDEBUG(D_acl) debug_printf_indent("end of %s: DEFER\n", acl_name);
+ if (acl_quit_check) goto badquit;
+ f.acl_temp_details = TRUE;
+ return DEFER;
+ }
+ break;
+
+ case ACL_DENY:
+ if (cond == OK)
+ {
+ HDEBUG(D_acl) debug_printf_indent("end of %s: DENY\n", acl_name);
+ if (acl_quit_check) goto badquit;
+ return FAIL;
+ }
+ break;
+
+ case ACL_DISCARD:
+ if (cond == OK || cond == DISCARD)
+ {
+ HDEBUG(D_acl) debug_printf_indent("end of %s: DISCARD\n", acl_name);
+ if (acl_quit_check) goto badquit;
+ return DISCARD;
+ }
+ if (endpass_seen)
+ {
+ HDEBUG(D_acl)
+ debug_printf_indent("discard: endpass encountered - denying access\n");
+ return cond;
+ }
+ break;
+
+ case ACL_DROP:
+ if (cond == OK)
+ {
+ HDEBUG(D_acl) debug_printf_indent("end of %s: DROP\n", acl_name);
+ if (acl_quit_check) goto badquit;
+ return FAIL_DROP;
+ }
+ break;
+
+ case ACL_REQUIRE:
+ if (cond != OK)
+ {
+ HDEBUG(D_acl) debug_printf_indent("end of %s: not OK\n", acl_name);
+ if (acl_quit_check) goto badquit;
+ return cond;
+ }
+ break;
+
+ case ACL_WARN:
+ if (cond == OK)
+ acl_warn(where, *user_msgptr, *log_msgptr);
+ else if (cond == DEFER && LOGGING(acl_warn_skipped))
+ log_write(0, LOG_MAIN, "%s Warning: ACL \"warn\" statement skipped: "
+ "condition test deferred%s%s", host_and_ident(TRUE),
+ (*log_msgptr == NULL)? US"" : US": ",
+ (*log_msgptr == NULL)? US"" : *log_msgptr);
+ *log_msgptr = *user_msgptr = NULL; /* In case implicit DENY follows */
+ break;
+
+ default:
+ log_write(0, LOG_MAIN|LOG_PANIC_DIE, "internal ACL error: unknown verb %d",
+ acl->verb);
+ break;
+ }
+
+ /* Pass to the next ACL item */
+
+ acl = acl->next;
+ }
+
+/* We have reached the end of the ACL. This is an implicit DENY. */
+
+HDEBUG(D_acl) debug_printf_indent("end of %s: implicit DENY\n", acl_name);
+return FAIL;
+
+badquit:
+ *log_msgptr = string_sprintf("QUIT or not-QUIT toplevel ACL may not fail "
+ "('%s' verb used incorrectly)", verbs[acl->verb]);
+ return ERROR;
+}
+
+
+
+
+/* Same args as acl_check_internal() above, but the string s is
+the name of an ACL followed optionally by up to 9 space-separated arguments.
+The name and args are separately expanded. Args go into $acl_arg globals. */
+static int
+acl_check_wargs(int where, address_item *addr, const uschar *s,
+ uschar **user_msgptr, uschar **log_msgptr)
+{
+uschar * tmp;
+uschar * tmp_arg[9]; /* must match acl_arg[] */
+uschar * sav_arg[9]; /* must match acl_arg[] */
+int sav_narg;
+uschar * name;
+int i;
+int ret;
+
+if (!(tmp = string_dequote(&s)) || !(name = expand_string(tmp)))
+ goto bad;
+
+for (i = 0; i < 9; i++)
+ {
+ while (*s && isspace(*s)) s++;
+ if (!*s) break;
+ if (!(tmp = string_dequote(&s)) || !(tmp_arg[i] = expand_string(tmp)))
+ {
+ tmp = name;
+ goto bad;
+ }
+ }
+
+sav_narg = acl_narg;
+acl_narg = i;
+for (i = 0; i < acl_narg; i++)
+ {
+ sav_arg[i] = acl_arg[i];
+ acl_arg[i] = tmp_arg[i];
+ }
+while (i < 9)
+ {
+ sav_arg[i] = acl_arg[i];
+ acl_arg[i++] = NULL;
+ }
+
+acl_level++;
+ret = acl_check_internal(where, addr, name, user_msgptr, log_msgptr);
+acl_level--;
+
+acl_narg = sav_narg;
+for (i = 0; i < 9; i++) acl_arg[i] = sav_arg[i];
+return ret;
+
+bad:
+if (f.expand_string_forcedfail) return ERROR;
+*log_msgptr = string_sprintf("failed to expand ACL string \"%s\": %s",
+ tmp, expand_string_message);
+return f.search_find_defer ? DEFER : ERROR;
+}
+
+
+
+/*************************************************
+* Check access using an ACL *
+*************************************************/
+
+/* Alternate interface for ACL, used by expansions */
+int
+acl_eval(int where, uschar *s, uschar **user_msgptr, uschar **log_msgptr)
+{
+address_item adb;
+address_item *addr = NULL;
+int rc;
+
+*user_msgptr = *log_msgptr = NULL;
+sender_verified_failed = NULL;
+ratelimiters_cmd = NULL;
+log_reject_target = LOG_MAIN|LOG_REJECT;
+
+if (where == ACL_WHERE_RCPT)
+ {
+ adb = address_defaults;
+ addr = &adb;
+ addr->address = expand_string(US"$local_part@$domain");
+ addr->domain = deliver_domain;
+ addr->local_part = deliver_localpart;
+ addr->cc_local_part = deliver_localpart;
+ addr->lc_local_part = deliver_localpart;
+ }
+
+acl_level++;
+rc = acl_check_internal(where, addr, s, user_msgptr, log_msgptr);
+acl_level--;
+return rc;
+}
+
+
+
+/* This is the external interface for ACL checks. It sets up an address and the
+expansions for $domain and $local_part when called after RCPT, then calls
+acl_check_internal() to do the actual work.
+
+Arguments:
+ where ACL_WHERE_xxxx indicating where called from
+ recipient RCPT address for RCPT check, else NULL
+ s the input string; NULL is the same as an empty ACL => DENY
+ user_msgptr where to put a user error (for SMTP response)
+ log_msgptr where to put a logging message (not for SMTP response)
+
+Returns: OK access is granted by an ACCEPT verb
+ DISCARD access is granted by a DISCARD verb
+ FAIL access is denied
+ FAIL_DROP access is denied; drop the connection
+ DEFER can't tell at the moment
+ ERROR disaster
+*/
+int acl_where = ACL_WHERE_UNKNOWN;
+
+int
+acl_check(int where, uschar *recipient, uschar *s, uschar **user_msgptr,
+ uschar **log_msgptr)
+{
+int rc;
+address_item adb;
+address_item *addr = NULL;
+
+*user_msgptr = *log_msgptr = NULL;
+sender_verified_failed = NULL;
+ratelimiters_cmd = NULL;
+log_reject_target = LOG_MAIN|LOG_REJECT;
+
+#ifndef DISABLE_PRDR
+if (where==ACL_WHERE_RCPT || where==ACL_WHERE_VRFY || where==ACL_WHERE_PRDR)
+#else
+if (where==ACL_WHERE_RCPT || where==ACL_WHERE_VRFY)
+#endif
+ {
+ adb = address_defaults;
+ addr = &adb;
+ addr->address = recipient;
+ if (deliver_split_address(addr) == DEFER)
+ {
+ *log_msgptr = US"defer in percent_hack_domains check";
+ return DEFER;
+ }
+#ifdef SUPPORT_I18N
+ if ((addr->prop.utf8_msg = message_smtputf8))
+ {
+ addr->prop.utf8_downcvt = message_utf8_downconvert == 1;
+ addr->prop.utf8_downcvt_maybe = message_utf8_downconvert == -1;
+ }
+#endif
+ deliver_domain = addr->domain;
+ deliver_localpart = addr->local_part;
+ }
+
+acl_where = where;
+acl_level = 0;
+rc = acl_check_internal(where, addr, s, user_msgptr, log_msgptr);
+acl_level = 0;
+acl_where = ACL_WHERE_UNKNOWN;
+
+/* Cutthrough - if requested,
+and WHERE_RCPT and not yet opened conn as result of recipient-verify,
+and rcpt acl returned accept,
+and first recipient (cancel on any subsequents)
+open one now and run it up to RCPT acceptance.
+A failed verify should cancel cutthrough request,
+and will pass the fail to the originator.
+Initial implementation: dual-write to spool.
+Assume the rxd datastream is now being copied byte-for-byte to an open cutthrough connection.
+
+Cease cutthrough copy on rxd final dot; do not send one.
+
+On a data acl, if not accept and a cutthrough conn is open, hard-close it (no SMTP niceness).
+
+On data acl accept, terminate the dataphase on an open cutthrough conn. If accepted or
+perm-rejected, reflect that to the original sender - and dump the spooled copy.
+If temp-reject, close the conn (and keep the spooled copy).
+If conn-failure, no action (and keep the spooled copy).
+*/
+switch (where)
+ {
+ case ACL_WHERE_RCPT:
+#ifndef DISABLE_PRDR
+ case ACL_WHERE_PRDR:
+#endif
+
+ if (f.host_checking_callout) /* -bhc mode */
+ cancel_cutthrough_connection(TRUE, US"host-checking mode");
+
+ else if ( rc == OK
+ && cutthrough.delivery
+ && rcpt_count > cutthrough.nrcpt
+ )
+ {
+ if ((rc = open_cutthrough_connection(addr)) == DEFER)
+ if (cutthrough.defer_pass)
+ {
+ uschar * s = addr->message;
+ /* Horrid kludge to recover target's SMTP message */
+ while (*s) s++;
+ do --s; while (!isdigit(*s));
+ if (*--s && isdigit(*s) && *--s && isdigit(*s)) *user_msgptr = s;
+ f.acl_temp_details = TRUE;
+ }
+ else
+ {
+ HDEBUG(D_acl) debug_printf_indent("cutthrough defer; will spool\n");
+ rc = OK;
+ }
+ }
+ else HDEBUG(D_acl) if (cutthrough.delivery)
+ if (rcpt_count <= cutthrough.nrcpt)
+ debug_printf_indent("ignore cutthrough request; nonfirst message\n");
+ else if (rc != OK)
+ debug_printf_indent("ignore cutthrough request; ACL did not accept\n");
+ break;
+
+ case ACL_WHERE_PREDATA:
+ if (rc == OK)
+ cutthrough_predata();
+ else
+ cancel_cutthrough_connection(TRUE, US"predata acl not ok");
+ break;
+
+ case ACL_WHERE_QUIT:
+ case ACL_WHERE_NOTQUIT:
+ /* Drop cutthrough conns, and drop heldopen verify conns if
+ the previous was not DATA */
+ {
+ uschar prev =
+ smtp_connection_had[SMTP_HBUFF_PREV(SMTP_HBUFF_PREV(smtp_ch_index))];
+ BOOL dropverify = !(prev == SCH_DATA || prev == SCH_BDAT);
+
+ cancel_cutthrough_connection(dropverify, US"quit or conndrop");
+ break;
+ }
+
+ default:
+ break;
+ }
+
+deliver_domain = deliver_localpart = deliver_address_data =
+ deliver_domain_data = sender_address_data = NULL;
+
+/* A DISCARD response is permitted only for message ACLs, excluding the PREDATA
+ACL, which is really in the middle of an SMTP command. */
+
+if (rc == DISCARD)
+ {
+ if (where > ACL_WHERE_NOTSMTP || where == ACL_WHERE_PREDATA)
+ {
+ log_write(0, LOG_MAIN|LOG_PANIC, "\"discard\" verb not allowed in %s "
+ "ACL", acl_wherenames[where]);
+ return ERROR;
+ }
+ return DISCARD;
+ }
+
+/* A DROP response is not permitted from MAILAUTH */
+
+if (rc == FAIL_DROP && where == ACL_WHERE_MAILAUTH)
+ {
+ log_write(0, LOG_MAIN|LOG_PANIC, "\"drop\" verb not allowed in %s "
+ "ACL", acl_wherenames[where]);
+ return ERROR;
+ }
+
+/* Before giving a response, take a look at the length of any user message, and
+split it up into multiple lines if possible. */
+
+*user_msgptr = string_split_message(*user_msgptr);
+if (fake_response != OK)
+ fake_response_text = string_split_message(fake_response_text);
+
+return rc;
+}
+
+
+/*************************************************
+* Create ACL variable *
+*************************************************/
+
+/* Create an ACL variable or reuse an existing one. ACL variables are in a
+binary tree (see tree.c) with acl_var_c and acl_var_m as root nodes.
+
+Argument:
+ name pointer to the variable's name, starting with c or m
+
+Returns the pointer to variable's tree node
+*/
+
+tree_node *
+acl_var_create(uschar * name)
+{
+tree_node * node, ** root = name[0] == 'c' ? &acl_var_c : &acl_var_m;
+if (!(node = tree_search(*root, name)))
+ {
+ node = store_get(sizeof(tree_node) + Ustrlen(name), is_tainted(name));
+ Ustrcpy(node->name, name);
+ (void)tree_insertnode(root, node);
+ }
+node->data.ptr = NULL;
+return node;
+}
+
+
+
+/*************************************************
+* Write an ACL variable in spool format *
+*************************************************/
+
+/* This function is used as a callback for tree_walk when writing variables to
+the spool file. To retain spool file compatibility, what is written is -aclc or
+-aclm followed by the rest of the name and the data length, space separated,
+then the value itself, starting on a new line, and terminated by an additional
+newline. When we had only numbered ACL variables, the first line might look
+like this: "-aclc 5 20". Now it might be "-aclc foo 20" for the variable called
+acl_cfoo.
+
+Arguments:
+ name of the variable
+ value of the variable
+ ctx FILE pointer (as a void pointer)
+
+Returns: nothing
+*/
+
+void
+acl_var_write(uschar *name, uschar *value, void *ctx)
+{
+FILE *f = (FILE *)ctx;
+if (is_tainted(value)) putc('-', f);
+fprintf(f, "-acl%c %s %d\n%s\n", name[0], name+1, Ustrlen(value), value);
+}
+
+/* vi: aw ai sw=2
+*/
+/* End of acl.c */