X-Git-Url: https://git.exim.org/exim.git/blobdiff_plain/b1c749bb7f147e7f9215fe6067c848cf02938b92..13b685f963e9313409f8350f718bac411829a5e7:/src/src/expand.c diff --git a/src/src/expand.c b/src/src/expand.c index 7ecfc09d4..e4e0d21e8 100644 --- a/src/src/expand.c +++ b/src/src/expand.c @@ -1,4 +1,4 @@ -/* $Cambridge: exim/src/src/expand.c,v 1.26 2005/06/16 14:10:13 ph10 Exp $ */ +/* $Cambridge: exim/src/src/expand.c,v 1.37 2005/08/01 13:20:28 ph10 Exp $ */ /************************************************* * Exim - an Internet mail transport agent * @@ -57,6 +57,8 @@ static uschar *item_table[] = { US"lookup", US"nhash", US"perl", + US"prvs", + US"prvscheck", US"readfile", US"readsocket", US"run", @@ -74,6 +76,8 @@ enum { EITEM_LOOKUP, EITEM_NHASH, EITEM_PERL, + EITEM_PRVS, + EITEM_PRVSCHECK, EITEM_READFILE, EITEM_READSOCK, EITEM_RUN, @@ -191,6 +195,7 @@ static uschar *cond_table[] = { US"match", US"match_address", US"match_domain", + US"match_ip", US"match_local_part", US"or", US"pam", @@ -229,6 +234,7 @@ enum { ECOND_MATCH, ECOND_MATCH_ADDRESS, ECOND_MATCH_DOMAIN, + ECOND_MATCH_IP, ECOND_MATCH_LOCAL_PART, ECOND_OR, ECOND_PAM, @@ -433,6 +439,9 @@ static var_entry var_table[] = { { "parent_local_part", vtype_stringptr, &deliver_localpart_parent }, { "pid", vtype_pid, NULL }, { "primary_hostname", vtype_stringptr, &primary_hostname }, + { "prvscheck_address", vtype_stringptr, &prvscheck_address }, + { "prvscheck_keynum", vtype_stringptr, &prvscheck_keynum }, + { "prvscheck_result", vtype_stringptr, &prvscheck_result }, { "qualify_domain", vtype_stringptr, &qualify_domain_sender }, { "qualify_recipient", vtype_stringptr, &qualify_domain_recipient }, { "rcpt_count", vtype_int, &rcpt_count }, @@ -1254,10 +1263,6 @@ while (last > first) switch (var_table[middle].type) { - case vtype_filter_int: - if (!filter_running) return NULL; - /* Fall through */ - #ifdef EXPERIMENTAL_DOMAINKEYS case vtype_dk_verify: @@ -1274,35 +1279,39 @@ while (last > first) if (Ustrcmp(var_table[middle].name, "dk_sender_source") == 0) switch(dk_verify_block->address_source) { - case DK_EXIM_ADDRESS_NONE: s = "0"; break; - case DK_EXIM_ADDRESS_FROM_FROM: s = "from"; break; - case DK_EXIM_ADDRESS_FROM_SENDER: s = "sender"; break; + case DK_EXIM_ADDRESS_NONE: s = US"0"; break; + case DK_EXIM_ADDRESS_FROM_FROM: s = US"from"; break; + case DK_EXIM_ADDRESS_FROM_SENDER: s = US"sender"; break; } if (Ustrcmp(var_table[middle].name, "dk_status") == 0) switch(dk_verify_block->result) { - case DK_EXIM_RESULT_ERR: s = "error"; break; - case DK_EXIM_RESULT_BAD_FORMAT: s = "bad format"; break; - case DK_EXIM_RESULT_NO_KEY: s = "no key"; break; - case DK_EXIM_RESULT_NO_SIGNATURE: s = "no signature"; break; - case DK_EXIM_RESULT_REVOKED: s = "revoked"; break; - case DK_EXIM_RESULT_NON_PARTICIPANT: s = "non-participant"; break; - case DK_EXIM_RESULT_GOOD: s = "good"; break; - case DK_EXIM_RESULT_BAD: s = "bad"; break; + case DK_EXIM_RESULT_ERR: s = US"error"; break; + case DK_EXIM_RESULT_BAD_FORMAT: s = US"bad format"; break; + case DK_EXIM_RESULT_NO_KEY: s = US"no key"; break; + case DK_EXIM_RESULT_NO_SIGNATURE: s = US"no signature"; break; + case DK_EXIM_RESULT_REVOKED: s = US"revoked"; break; + case DK_EXIM_RESULT_NON_PARTICIPANT: s = US"non-participant"; break; + case DK_EXIM_RESULT_GOOD: s = US"good"; break; + case DK_EXIM_RESULT_BAD: s = US"bad"; break; } if (Ustrcmp(var_table[middle].name, "dk_signsall") == 0) - s = (dk_verify_block->signsall)? "1" : "0"; + s = (dk_verify_block->signsall)? US"1" : US"0"; if (Ustrcmp(var_table[middle].name, "dk_testing") == 0) - s = (dk_verify_block->testing)? "1" : "0"; + s = (dk_verify_block->testing)? US"1" : US"0"; if (Ustrcmp(var_table[middle].name, "dk_is_signed") == 0) - s = (dk_verify_block->is_signed)? "1" : "0"; + s = (dk_verify_block->is_signed)? US"1" : US"0"; return (s == NULL)? US"" : s; #endif + case vtype_filter_int: + if (!filter_running) return NULL; + /* Fall through */ + /* VVVVVVVVVVVV */ case vtype_int: sprintf(CS var_buffer, "%d", *(int *)(var_table[middle].value)); /* Integer */ return var_buffer; @@ -1794,6 +1803,7 @@ switch(cond_type) variables if it succeeds match_address: matches in an address list match_domain: matches in a domain list + match_ip: matches a host list that is restricted to IP addresses match_local_part: matches in a local part list crypteq: encrypts plaintext and compares against an encrypted text, using crypt(), crypt16(), MD5 or SHA-1 @@ -1802,6 +1812,7 @@ switch(cond_type) case ECOND_MATCH: case ECOND_MATCH_ADDRESS: case ECOND_MATCH_DOMAIN: + case ECOND_MATCH_IP: case ECOND_MATCH_LOCAL_PART: case ECOND_CRYPTEQ: @@ -1955,11 +1966,46 @@ switch(cond_type) MCL_DOMAIN + MCL_NOEXPAND, TRUE, NULL); goto MATCHED_SOMETHING; + case ECOND_MATCH_IP: /* Match IP address in a host list */ + if (sub[0][0] != 0 && string_is_ip_address(sub[0], NULL) <= 0) + { + expand_string_message = string_sprintf("\"%s\" is not an IP address", + sub[0]); + return NULL; + } + else + { + unsigned int *nullcache = NULL; + check_host_block cb; + + cb.host_name = US""; + cb.host_address = sub[0]; + + /* If the host address starts off ::ffff: it is an IPv6 address in + IPv4-compatible mode. Find the IPv4 part for checking against IPv4 + addresses. */ + + cb.host_ipv4 = (Ustrncmp(cb.host_address, "::ffff:", 7) == 0)? + cb.host_address + 7 : cb.host_address; + + rc = match_check_list( + &sub[1], /* the list */ + 0, /* separator character */ + &hostlist_anchor, /* anchor pointer */ + &nullcache, /* cache pointer */ + check_host, /* function for testing */ + &cb, /* argument for function */ + MCL_HOST, /* type of check */ + sub[0], /* text for debugging */ + NULL); /* where to pass back data */ + } + goto MATCHED_SOMETHING; + case ECOND_MATCH_LOCAL_PART: rc = match_isinlist(sub[0], &(sub[1]), 0, &localpartlist_anchor, NULL, MCL_LOCALPART + MCL_NOEXPAND, TRUE, NULL); /* Fall through */ - + /* VVVVVVVVVVVV */ MATCHED_SOMETHING: switch(rc) { @@ -2418,8 +2464,6 @@ return rc; - - /************************************************* * Handle MD5 or SHA-1 computation for HMAC * *************************************************/ @@ -2465,6 +2509,110 @@ else +/******************************************************** +* prvs: Get last three digits of days since Jan 1, 1970 * +********************************************************/ + +/* This is needed to implement the "prvs" BATV reverse + path signing scheme + +Argument: integer "days" offset to add or substract to + or from the current number of days. + +Returns: pointer to string containing the last three + digits of the number of days since Jan 1, 1970, + modified by the offset argument, NULL if there + was an error in the conversion. + +*/ + +static uschar * +prvs_daystamp(int day_offset) +{ +uschar *days = store_get(16); +(void)string_format(days, 16, TIME_T_FMT, + (time(NULL) + day_offset*86400)/86400); +return (Ustrlen(days) >= 3) ? &days[Ustrlen(days)-3] : US"100"; +} + + + +/******************************************************** +* prvs: perform HMAC-SHA1 computation of prvs bits * +********************************************************/ + +/* This is needed to implement the "prvs" BATV reverse + path signing scheme + +Arguments: + address RFC2821 Address to use + key The key to use (must be less than 64 characters + in size) + key_num Single-digit key number to use. Defaults to + '0' when NULL. + +Returns: pointer to string containing the first three + bytes of the final hash in hex format, NULL if + there was an error in the process. +*/ + +static uschar * +prvs_hmac_sha1(uschar *address, uschar *key, uschar *key_num, uschar *daystamp) +{ +uschar *hash_source, *p; +int size = 0,offset = 0,i; +sha1 sha1_base; +void *use_base = &sha1_base; +uschar innerhash[20]; +uschar finalhash[20]; +uschar innerkey[64]; +uschar outerkey[64]; +uschar *finalhash_hex = store_get(40); + +if (key_num == NULL) + key_num = US"0"; + +if (Ustrlen(key) > 64) + return NULL; + +hash_source = string_cat(NULL,&size,&offset,key_num,1); +string_cat(hash_source,&size,&offset,daystamp,3); +string_cat(hash_source,&size,&offset,address,Ustrlen(address)); +hash_source[offset] = '\0'; + +DEBUG(D_expand) debug_printf("prvs: hash source is '%s'\n", hash_source); + +memset(innerkey, 0x36, 64); +memset(outerkey, 0x5c, 64); + +for (i = 0; i < Ustrlen(key); i++) + { + innerkey[i] ^= key[i]; + outerkey[i] ^= key[i]; + } + +chash_start(HMAC_SHA1, use_base); +chash_mid(HMAC_SHA1, use_base, innerkey); +chash_end(HMAC_SHA1, use_base, hash_source, offset, innerhash); + +chash_start(HMAC_SHA1, use_base); +chash_mid(HMAC_SHA1, use_base, outerkey); +chash_end(HMAC_SHA1, use_base, innerhash, 20, finalhash); + +p = finalhash_hex; +for (i = 0; i < 3; i++) + { + *p++ = hex_digits[(finalhash[i] & 0xf0) >> 4]; + *p++ = hex_digits[finalhash[i] & 0x0f]; + } +*p = '\0'; + +return finalhash_hex; +} + + + + /************************************************* * Join a file onto the output string * *************************************************/ @@ -2977,7 +3125,7 @@ while (*s != 0) /* Check that a key was provided for those lookup types that need it, and was not supplied for those that use the query style. */ - if (!mac_islookup(stype, lookup_querystyle)) + if (!mac_islookup(stype, lookup_querystyle|lookup_absfilequery)) { if (key == NULL) { @@ -2997,7 +3145,9 @@ while (*s != 0) } /* Get the next string in brackets and expand it. It is the file name for - single-key+file lookups, and the whole query otherwise. */ + single-key+file lookups, and the whole query otherwise. In the case of + queries that also require a file name (e.g. sqlite), the file name comes + first. */ if (*s != '{') goto EXPAND_FAILED_CURLY; filename = expand_string_internal(s+1, TRUE, &s, skipping); @@ -3006,12 +3156,30 @@ while (*s != 0) while (isspace(*s)) s++; /* If this isn't a single-key+file lookup, re-arrange the variables - to be appropriate for the search_ functions. */ + to be appropriate for the search_ functions. For query-style lookups, + there is just a "key", and no file name. For the special query-style + + file types, the query (i.e. "key") starts with a file name. */ if (key == NULL) { + while (isspace(*filename)) filename++; key = filename; - filename = NULL; + + if (mac_islookup(stype, lookup_querystyle)) + { + filename = NULL; + } + else + { + if (*filename != '/') + { + expand_string_message = string_sprintf( + "absolute file name expected for \"%s\" lookup", name); + goto EXPAND_FAILED; + } + while (*key != 0 && !isspace(*key)) key++; + if (*key != 0) *key++ = 0; + } } /* If skipping, don't do the next bit - just lookup_value == NULL, as if @@ -3163,6 +3331,172 @@ while (*s != 0) } #endif /* EXIM_PERL */ + /* Transform email address to "prvs" scheme to use + as BATV-signed return path */ + + case EITEM_PRVS: + { + uschar *sub_arg[3]; + uschar *p,*domain; + + switch(read_subs(sub_arg, 3, 2, &s, skipping, TRUE, US"prvs")) + { + case 1: goto EXPAND_FAILED_CURLY; + case 2: + case 3: goto EXPAND_FAILED; + } + + /* If skipping, we don't actually do anything */ + if (skipping) continue; + + /* sub_arg[0] is the address */ + domain = Ustrrchr(sub_arg[0],'@'); + if ( (domain == NULL) || (domain == sub_arg[0]) || (Ustrlen(domain) == 1) ) + { + expand_string_message = US"first parameter must be a qualified email address"; + goto EXPAND_FAILED; + } + + /* Calculate the hash */ + p = prvs_hmac_sha1(sub_arg[0],sub_arg[1],sub_arg[2],prvs_daystamp(7)); + if (p == NULL) + { + expand_string_message = US"hmac-sha1 conversion failed"; + goto EXPAND_FAILED; + } + + /* Now separate the domain from the local part */ + *domain++ = '\0'; + + yield = string_cat(yield,&size,&ptr,US"prvs=",5); + string_cat(yield,&size,&ptr,sub_arg[0],Ustrlen(sub_arg[0])); + string_cat(yield,&size,&ptr,US"/",1); + string_cat(yield,&size,&ptr,(sub_arg[2] != NULL) ? sub_arg[2] : US"0", 1); + string_cat(yield,&size,&ptr,prvs_daystamp(7),3); + string_cat(yield,&size,&ptr,p,6); + string_cat(yield,&size,&ptr,US"@",1); + string_cat(yield,&size,&ptr,domain,Ustrlen(domain)); + + continue; + } + + /* Check a prvs-encoded address for validity */ + + case EITEM_PRVSCHECK: + { + uschar *sub_arg[3]; + int mysize = 0, myptr = 0; + const pcre *re; + uschar *p; + /* Ugliness: We want to expand parameter 1 first, then set + up expansion variables that are used in the expansion of + parameter 2. So we clone the string for the first + expansion, where we only expand paramter 1. */ + uschar *s_backup = string_copy(s); + + /* Reset expansion variables */ + prvscheck_result = NULL; + prvscheck_address = NULL; + prvscheck_keynum = NULL; + + switch(read_subs(sub_arg, 1, 1, &s_backup, skipping, FALSE, US"prvs")) + { + case 1: goto EXPAND_FAILED_CURLY; + case 2: + case 3: goto EXPAND_FAILED; + } + + re = regex_must_compile(US"^prvs\\=(.+)\\/([0-9])([0-9]{3})([A-F0-9]{6})\\@(.+)$", + TRUE,FALSE); + + if (regex_match_and_setup(re,sub_arg[0],0,-1)) { + uschar *local_part = string_copyn(expand_nstring[1],expand_nlength[1]); + uschar *key_num = string_copyn(expand_nstring[2],expand_nlength[2]); + uschar *daystamp = string_copyn(expand_nstring[3],expand_nlength[3]); + uschar *hash = string_copyn(expand_nstring[4],expand_nlength[4]); + uschar *domain = string_copyn(expand_nstring[5],expand_nlength[5]); + + DEBUG(D_expand) debug_printf("prvscheck localpart: %s\n", local_part); + DEBUG(D_expand) debug_printf("prvscheck key number: %s\n", key_num); + DEBUG(D_expand) debug_printf("prvscheck daystamp: %s\n", daystamp); + DEBUG(D_expand) debug_printf("prvscheck hash: %s\n", hash); + DEBUG(D_expand) debug_printf("prvscheck domain: %s\n", domain); + + /* Set up expansion variables */ + prvscheck_address = string_cat(NULL, &mysize, &myptr, local_part, Ustrlen(local_part)); + string_cat(prvscheck_address,&mysize,&myptr,US"@",1); + string_cat(prvscheck_address,&mysize,&myptr,domain,Ustrlen(domain)); + prvscheck_address[myptr] = '\0'; + prvscheck_keynum = string_copy(key_num); + + /* Now re-expand all arguments in the usual manner */ + switch(read_subs(sub_arg, 3, 3, &s, skipping, TRUE, US"prvs")) + { + case 1: goto EXPAND_FAILED_CURLY; + case 2: + case 3: goto EXPAND_FAILED; + } + + if (*sub_arg[2] == '\0') + yield = string_cat(yield,&size,&ptr,prvscheck_address,Ustrlen(prvscheck_address)); + else + yield = string_cat(yield,&size,&ptr,sub_arg[2],Ustrlen(sub_arg[2])); + + /* Now we have the key and can check the address. */ + p = prvs_hmac_sha1(prvscheck_address, sub_arg[1], prvscheck_keynum, daystamp); + if (p == NULL) + { + expand_string_message = US"hmac-sha1 conversion failed"; + goto EXPAND_FAILED; + } + + DEBUG(D_expand) debug_printf("prvscheck: received hash is %s\n", hash); + DEBUG(D_expand) debug_printf("prvscheck: own hash is %s\n", p); + if (Ustrcmp(p,hash) == 0) + { + /* Success, valid BATV address. Now check the expiry date. */ + uschar *now = prvs_daystamp(0); + unsigned int inow = 0,iexpire = 1; + + (void)sscanf(CS now,"%u",&inow); + (void)sscanf(CS daystamp,"%u",&iexpire); + + /* When "iexpire" is < 7, a "flip" has occured. + Adjust "inow" accordingly. */ + if ( (iexpire < 7) && (inow >= 993) ) inow = 0; + + if (iexpire > inow) + { + prvscheck_result = US"1"; + DEBUG(D_expand) debug_printf("prvscheck: success, $pvrs_result set to 1\n"); + } + else + { + prvscheck_result = NULL; + DEBUG(D_expand) debug_printf("prvscheck: signature expired, $pvrs_result unset\n"); + } + } + else + { + prvscheck_result = NULL; + DEBUG(D_expand) debug_printf("prvscheck: hash failure, $pvrs_result unset\n"); + } + } + else + { + /* Does not look like a prvs encoded address, return the empty string. + We need to make sure all subs are expanded first. */ + switch(read_subs(sub_arg, 3, 3, &s, skipping, TRUE, US"prvs")) + { + case 1: goto EXPAND_FAILED_CURLY; + case 2: + case 3: goto EXPAND_FAILED; + } + } + + continue; + } + /* Handle "readfile" to insert an entire file */ case EITEM_READFILE: @@ -3197,7 +3531,7 @@ while (*s != 0) } yield = cat_file(f, yield, &size, &ptr, sub_arg[1]); - fclose(f); + (void)fclose(f); continue; } @@ -3290,7 +3624,7 @@ while (*s != 0) alarm(timeout); yield = cat_file(f, yield, &size, &ptr, sub_arg[3]); alarm(0); - fclose(f); + (void)fclose(f); /* After a timeout, we restore the pointer in the result, that is, make sure we add nothing from the socket. */ @@ -3387,7 +3721,7 @@ while (*s != 0) /* Nothing is written to the standard input. */ - close(fd_in); + (void)close(fd_in); /* Wait for the process to finish, applying the timeout, and inspect its return code for serious disasters. Simple non-zero returns are passed on. @@ -3418,7 +3752,7 @@ while (*s != 0) f = fdopen(fd_out, "rb"); lookup_value = NULL; lookup_value = cat_file(f, lookup_value, &lsize, &lptr, NULL); - fclose(f); + (void)fclose(f); } /* Process the yes/no strings; $value may be useful in both cases */ @@ -4769,7 +5103,6 @@ return -2; } - /************************************************* ************************************************** * Stand-alone test program *