X-Git-Url: https://vcs.fsf.org/?p=exim.git;a=blobdiff_plain;f=src%2Fsrc%2Fexpand.c;h=ec4dd71f94392407f12a78208b6af1c107825871;hp=7d6d15041db26354f7573880e2eaa3006731e5fa;hb=ac53fcdaf9c772ee8e70ca4f14ed19b39e12eb68;hpb=c8307c12debe200307fd8ffe5539c9170dc1e8a5 diff --git a/src/src/expand.c b/src/src/expand.c index 7d6d15041..ec4dd71f9 100644 --- a/src/src/expand.c +++ b/src/src/expand.c @@ -1,10 +1,8 @@ -/* $Cambridge: exim/src/src/expand.c,v 1.99 2009/06/27 19:37:17 tom Exp $ */ - /************************************************* * Exim - an Internet mail transport agent * *************************************************/ -/* Copyright (c) University of Cambridge 1995 - 2007 */ +/* Copyright (c) University of Cambridge 1995 - 2009 */ /* See the file NOTICE for conditions of use and distribution. */ @@ -156,6 +154,7 @@ static uschar *op_table_underscore[] = { US"from_utf8", US"local_part", US"quote_local_part", + US"reverse_ip", US"time_eval", US"time_interval"}; @@ -163,6 +162,7 @@ enum { EOP_FROM_UTF8, EOP_LOCAL_PART, EOP_QUOTE_LOCAL_PART, + EOP_REVERSE_IP, EOP_TIME_EVAL, EOP_TIME_INTERVAL }; @@ -187,6 +187,7 @@ static uschar *op_table_main[] = { US"nh", US"nhash", US"quote", + US"randint", US"rfc2047", US"rfc2047d", US"rxquote", @@ -219,6 +220,7 @@ enum { EOP_NH, EOP_NHASH, EOP_QUOTE, + EOP_RANDINT, EOP_RFC2047, EOP_RFC2047D, EOP_RXQUOTE, @@ -242,6 +244,8 @@ static uschar *cond_table[] = { US">", US">=", US"and", + US"bool", + US"bool_lax", US"crypteq", US"def", US"eq", @@ -283,6 +287,8 @@ enum { ECOND_NUM_G, ECOND_NUM_GE, ECOND_AND, + ECOND_BOOL, + ECOND_BOOL_LAX, ECOND_CRYPTEQ, ECOND_DEF, ECOND_STR_EQ, @@ -320,9 +326,9 @@ enum { /* Type for main variable table */ typedef struct { - char *name; - int type; - void *value; + const char *name; + int type; + void *value; } var_entry; /* Type for entries pointing to address/length pairs. Not currently @@ -381,6 +387,9 @@ static var_entry var_table[] = { { "authenticated_id", vtype_stringptr, &authenticated_id }, { "authenticated_sender",vtype_stringptr, &authenticated_sender }, { "authentication_failed",vtype_int, &authentication_failed }, +#ifdef WITH_CONTENT_SCAN + { "av_failed", vtype_int, &av_failed }, +#endif #ifdef EXPERIMENTAL_BRIGHTMAIL { "bmi_alt_location", vtype_stringptr, &bmi_alt_location }, { "bmi_base64_tracker_verdict", vtype_stringptr, &bmi_base64_tracker_verdict }, @@ -411,6 +420,7 @@ static var_entry var_table[] = { { "dkim_canon_headers", vtype_dkim, (void *)DKIM_CANON_HEADERS }, { "dkim_copiedheaders", vtype_dkim, (void *)DKIM_COPIEDHEADERS }, { "dkim_created", vtype_dkim, (void *)DKIM_CREATED }, + { "dkim_cur_signer", vtype_stringptr, &dkim_cur_signer }, { "dkim_domain", vtype_stringptr, &dkim_signing_domain }, { "dkim_expires", vtype_dkim, (void *)DKIM_EXPIRES }, { "dkim_headernames", vtype_dkim, (void *)DKIM_HEADERNAMES }, @@ -421,7 +431,7 @@ static var_entry var_table[] = { { "dkim_key_srvtype", vtype_dkim, (void *)DKIM_KEY_SRVTYPE }, { "dkim_key_testing", vtype_dkim, (void *)DKIM_KEY_TESTING }, { "dkim_selector", vtype_stringptr, &dkim_signing_selector }, - { "dkim_signing_domains",vtype_stringptr, &dkim_signing_domains }, + { "dkim_signers", vtype_stringptr, &dkim_signers }, { "dkim_verify_reason", vtype_dkim, (void *)DKIM_VERIFY_REASON }, { "dkim_verify_status", vtype_dkim, (void *)DKIM_VERIFY_STATUS}, #endif @@ -623,9 +633,9 @@ static BOOL malformed_header; /* For textual hashes */ -static char *hashcodes = "abcdefghijklmnopqrtsuvwxyz" - "ABCDEFGHIJKLMNOPQRSTUVWXYZ" - "0123456789"; +static const char *hashcodes = "abcdefghijklmnopqrtsuvwxyz" + "ABCDEFGHIJKLMNOPQRSTUVWXYZ" + "0123456789"; enum { HMAC_MD5, HMAC_SHA1 }; @@ -727,6 +737,8 @@ or "false" value. Failure of the expansion yields FALSE; logged unless it was a forced fail or lookup defer. All store used by the function can be released on exit. +The actual false-value tests should be replicated for ECOND_BOOL_LAX. + Arguments: condition the condition string m1 text to be incorporated in panic error @@ -756,6 +768,75 @@ return rc; +/************************************************* +* Pseudo-random number generation * +*************************************************/ + +/* Pseudo-random number generation. The result is not "expected" to be +cryptographically strong but not so weak that someone will shoot themselves +in the foot using it as a nonce in some email header scheme or whatever +weirdness they'll twist this into. The result should ideally handle fork(). + +However, if we're stuck unable to provide this, then we'll fall back to +appallingly bad randomness. + +If SUPPORT_TLS is defined and OpenSSL is used, then this will not be used. +The GNUTLS randomness functions found do not seem amenable to extracting +random numbers outside of a TLS context. Any volunteers? + +Arguments: + max range maximum +Returns a random number in range [0, max-1] +*/ + +#if !defined(SUPPORT_TLS) || defined(USE_GNUTLS) +int +pseudo_random_number(int max) +{ + static pid_t pid = 0; + pid_t p2; +#if defined(HAVE_SRANDOM) && !defined(HAVE_SRANDOMDEV) + struct timeval tv; +#endif + + p2 = getpid(); + if (p2 != pid) + { + if (pid != 0) + { + +#ifdef HAVE_ARC4RANDOM + /* cryptographically strong randomness, common on *BSD platforms, not + so much elsewhere. Alas. */ + arc4random_stir(); +#elif defined(HAVE_SRANDOM) || defined(HAVE_SRANDOMDEV) +#ifdef HAVE_SRANDOMDEV + /* uses random(4) for seeding */ + srandomdev(); +#else + gettimeofday(&tv, NULL); + srandom(tv.tv_sec | tv.tv_usec | getpid()); +#endif +#else + /* Poor randomness and no seeding here */ +#endif + + } + pid = p2; + } + +#ifdef HAVE_ARC4RANDOM + return arc4random() % max; +#elif defined(HAVE_SRANDOM) || defined(HAVE_SRANDOMDEV) + return random() % max; +#else + /* This one returns a 16-bit number, definitely not crypto-strong */ + return random_number(max); +#endif +} + +#endif + /************************************************* * Pick out a name from a string * *************************************************/ @@ -1507,7 +1588,7 @@ while (last > first) return tod_stamp(tod_zulu); case vtype_todlf: /* Log file datestamp tod */ - return tod_stamp(tod_log_datestamp); + return tod_stamp(tod_log_datestamp_daily); case vtype_reply: /* Get reply address */ s = find_header(US"reply-to:", exists_only, newsize, TRUE, @@ -1567,7 +1648,7 @@ while (last > first) #ifndef DISABLE_DKIM case vtype_dkim: - return dkim_exim_expand_query((int)var_table[middle].value); + return dkim_exim_expand_query((int)(long)var_table[middle].value); #endif } @@ -2408,6 +2489,80 @@ switch(cond_type) } + /* The bool{} expansion condition maps a string to boolean. + The values supported should match those supported by the ACL condition + (acl.c, ACLC_CONDITION) so that we keep to a minimum the different ideas + of true/false. Note that Router "condition" rules have a different + interpretation, where general data can be used and only a few values + map to FALSE. + Note that readconf.c boolean matching, for boolean configuration options, + only matches true/yes/false/no. + The bool_lax{} condition matches the Router logic, which is much more + liberal. */ + case ECOND_BOOL: + case ECOND_BOOL_LAX: + { + uschar *sub_arg[1]; + uschar *t, *t2; + uschar *ourname; + size_t len; + BOOL boolvalue = FALSE; + while (isspace(*s)) s++; + if (*s != '{') goto COND_FAILED_CURLY_START; + ourname = cond_type == ECOND_BOOL_LAX ? US"bool_lax" : US"bool"; + switch(read_subs(sub_arg, 1, 1, &s, yield == NULL, FALSE, ourname)) + { + case 1: expand_string_message = string_sprintf( + "too few arguments or bracketing error for %s", + ourname); + /*FALLTHROUGH*/ + case 2: + case 3: return NULL; + } + t = sub_arg[0]; + while (isspace(*t)) t++; + len = Ustrlen(t); + if (len) + { + /* trailing whitespace: seems like a good idea to ignore it too */ + t2 = t + len - 1; + while (isspace(*t2)) t2--; + if (t2 != (t + len)) + { + *++t2 = '\0'; + len = t2 - t; + } + } + DEBUG(D_expand) + debug_printf("considering %s: %s\n", ourname, len ? t : US""); + /* logic for the lax case from expand_check_condition(), which also does + expands, and the logic is both short and stable enough that there should + be no maintenance burden from replicating it. */ + if (len == 0) + boolvalue = FALSE; + else if (Ustrspn(t, "0123456789") == len) + { + boolvalue = (Uatoi(t) == 0) ? FALSE : TRUE; + /* expand_check_condition only does a literal string "0" check */ + if ((cond_type == ECOND_BOOL_LAX) && (len > 1)) + boolvalue = TRUE; + } + else if (strcmpic(t, US"true") == 0 || strcmpic(t, US"yes") == 0) + boolvalue = TRUE; + else if (strcmpic(t, US"false") == 0 || strcmpic(t, US"no") == 0) + boolvalue = FALSE; + else if (cond_type == ECOND_BOOL_LAX) + boolvalue = TRUE; + else + { + expand_string_message = string_sprintf("unrecognised boolean " + "value \"%s\"", t); + return NULL; + } + if (yield != NULL) *yield = (boolvalue == testfor); + return s; + } + /* Unknown condition */ default: @@ -2952,9 +3107,47 @@ if (*error == NULL) int op = *s++; int y = eval_op_unary(&s, decimal, error); if (*error != NULL) break; - if (op == '*') x *= y; - else if (op == '/') x /= y; - else x %= y; + /* SIGFPE both on div/mod by zero and on INT_MIN / -1, which would give + * a value of INT_MAX+1. Note that INT_MIN * -1 gives INT_MIN for me, which + * is a bug somewhere in [gcc 4.2.1, FreeBSD, amd64]. In fact, -N*-M where + * -N*M is INT_MIN will yielf INT_MIN. + * Since we don't support floating point, this is somewhat simpler. + * Ideally, we'd return an error, but since we overflow for all other + * arithmetic, consistency suggests otherwise, but what's the correct value + * to use? There is none. + * The C standard guarantees overflow for unsigned arithmetic but signed + * overflow invokes undefined behaviour; in practice, this is overflow + * except for converting INT_MIN to INT_MAX+1. We also can't guarantee + * that long/longlong larger than int are available, or we could just work + * with larger types. We should consider whether to guarantee 32bit eval + * and 64-bit working variables, with errors returned. For now ... + * So, the only SIGFPEs occur with a non-shrinking div/mod, thus -1; we + * can just let the other invalid results occur otherwise, as they have + * until now. For this one case, we can coerce. + */ + if (y == -1 && x == INT_MIN && op != '*') + { + DEBUG(D_expand) + debug_printf("Integer exception dodging: %d%c-1 coerced to %d\n", + INT_MIN, op, INT_MAX); + x = INT_MAX; + continue; + } + if (op == '*') + x *= y; + else + { + if (y == 0) + { + *error = (op == '/') ? US"divide by zero" : US"modulo by zero"; + x = 0; + break; + } + if (op == '/') + x /= y; + else + x %= y; + } } } *sptr = s; @@ -3521,8 +3714,8 @@ while (*s != 0) if (search_find_defer) { expand_string_message = - string_sprintf("lookup of \"%s\" gave DEFER: %s", key, - search_error_message); + string_sprintf("lookup of \"%s\" gave DEFER: %s", + string_printing2(key, FALSE), search_error_message); goto EXPAND_FAILED; } if (expand_setup > 0) expand_nmax = expand_setup; @@ -4211,13 +4404,24 @@ while (*s != 0) (void)close(fd_in); + /* Read the pipe to get the command's output into $value (which is kept + in lookup_value). Read during execution, so that if the output exceeds + the OS pipe buffer limit, we don't block forever. */ + + f = fdopen(fd_out, "rb"); + sigalrm_seen = FALSE; + alarm(60); + lookup_value = cat_file(f, lookup_value, &lsize, &lptr, NULL); + alarm(0); + (void)fclose(f); + /* Wait for the process to finish, applying the timeout, and inspect its return code for serious disasters. Simple non-zero returns are passed on. */ - if ((runrc = child_close(pid, 60)) < 0) + if (sigalrm_seen == TRUE || (runrc = child_close(pid, 30)) < 0) { - if (runrc == -256) + if (sigalrm_seen == TRUE || runrc == -256) { expand_string_message = string_sprintf("command timed out"); killpg(pid, SIGKILL); /* Kill the whole process group */ @@ -4233,14 +4437,6 @@ while (*s != 0) goto EXPAND_FAILED; } - - /* Read the pipe to get the command's output into $value (which is kept - in lookup_value). */ - - f = fdopen(fd_out, "rb"); - lookup_value = NULL; - lookup_value = cat_file(f, lookup_value, &lsize, &lptr, NULL); - (void)fclose(f); } /* Process the yes/no strings; $value may be useful in both cases */ @@ -5352,8 +5548,8 @@ while (*s != 0) goto EXPAND_FAILED; } - if (lookup_list[n].quote != NULL) - sub = (lookup_list[n].quote)(sub, opt); + if (lookup_list[n]->quote != NULL) + sub = (lookup_list[n]->quote)(sub, opt); else if (opt != NULL) sub = NULL; if (sub == NULL) @@ -5654,6 +5850,40 @@ while (*s != 0) continue; } + /* pseudo-random number less than N */ + + case EOP_RANDINT: + { + int max; + uschar *s; + + max = expand_string_integer(sub, TRUE); + if (expand_string_message != NULL) + goto EXPAND_FAILED; + s = string_sprintf("%d", pseudo_random_number(max)); + yield = string_cat(yield, &size, &ptr, s, Ustrlen(s)); + continue; + } + + /* Reverse IP, including IPv6 to dotted-nibble */ + + case EOP_REVERSE_IP: + { + int family, maskptr; + uschar reversed[128]; + + family = string_is_ip_address(sub, &maskptr); + if (family == 0) + { + expand_string_message = string_sprintf( + "reverse_ip() not given an IP address [%s]", sub); + goto EXPAND_FAILED; + } + invert_address(reversed, sub); + yield = string_cat(yield, &size, &ptr, reversed, Ustrlen(reversed)); + continue; + } + /* Unknown operator */ default: