diff options
Diffstat (limited to 'contrib/dlz/drivers/dlz_postgres_driver.c')
| -rw-r--r-- | contrib/dlz/drivers/dlz_postgres_driver.c | 1372 |
1 files changed, 1372 insertions, 0 deletions
diff --git a/contrib/dlz/drivers/dlz_postgres_driver.c b/contrib/dlz/drivers/dlz_postgres_driver.c new file mode 100644 index 0000000..5cad59e --- /dev/null +++ b/contrib/dlz/drivers/dlz_postgres_driver.c @@ -0,0 +1,1372 @@ +/* + * Copyright (C) 2002 Stichting NLnet, Netherlands, stichting@nlnet.nl. + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the + * above copyright notice and this permission notice appear in all + * copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND STICHTING NLNET + * DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL + * STICHTING NLNET BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR + * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS + * OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE + * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE + * USE OR PERFORMANCE OF THIS SOFTWARE. + * + * The development of Dynamically Loadable Zones (DLZ) for Bind 9 was + * conceived and contributed by Rob Butler. + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the + * above copyright notice and this permission notice appear in all + * copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND ROB BUTLER + * DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL + * ROB BUTLER BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR + * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS + * OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE + * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE + * USE OR PERFORMANCE OF THIS SOFTWARE. + */ + +/* + * Copyright (C) 1999-2001 Internet Software Consortium. + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM + * DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL + * INTERNET SOFTWARE CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, + * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING + * FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, + * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION + * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ + +#ifdef DLZ_POSTGRES + +#include <config.h> +#include <stdio.h> +#include <string.h> +#include <stdlib.h> + +#include <dns/log.h> +#include <dns/sdlz.h> +#include <dns/result.h> + +#include <isc/mem.h> +#include <isc/platform.h> +#include <isc/print.h> +#include <isc/result.h> +#include <isc/string.h> +#include <isc/util.h> + +#include <named/globals.h> + +#include <dlz/sdlz_helper.h> +#include <dlz/dlz_postgres_driver.h> + +/* temporarily include time. */ +#include <time.h> + +#include <libpq-fe.h> + +static dns_sdlzimplementation_t *dlz_postgres = NULL; + +#define dbc_search_limit 30 +#define ALLNODES 1 +#define ALLOWXFR 2 +#define AUTHORITY 3 +#define FINDZONE 4 +#define LOOKUP 5 + +/* + * Private methods + */ + +/* --------------- + * Escaping arbitrary strings to get valid SQL strings/identifiers. + * + * Replaces "\\" with "\\\\" and "'" with "''". + * length is the length of the buffer pointed to by + * from. The buffer at to must be at least 2*length + 1 characters + * long. A terminating NUL character is written. + * + * NOTICE!!! + * This function was borrowed directly from PostgreSQL's libpq. + * The function was originally called PQescapeString and renamed + * to postgres_makesafe to avoid a naming collision. + * PQescapeString is a new function made available in Postgres 7.2. + * For some reason the function is not properly exported on Win32 + * builds making the function unavailable on Windows. Also, since + * this function is new it would require building this driver with + * the libpq 7.2. By borrowing this function the Windows problem + * is solved, and the dependence on libpq 7.2 is removed. Libpq is + * still required of course, but an older version should work now too. + * + * The copyright statements from the original file containing this + * function are included below: + * Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group + * Portions Copyright (c) 1994, Regents of the University of California + * --------------- + */ + +static size_t +postgres_makesafe(char *to, const char *from, size_t length) +{ + const char *source = from; + char *target = to; + unsigned int remaining = length; + + while (remaining > 0) + { + switch (*source) + { + case '\\': + *target = '\\'; + target++; + *target = '\\'; + /* target and remaining are updated below. */ + break; + + case '\'': + *target = '\''; + target++; + *target = '\''; + /* target and remaining are updated below. */ + break; + + default: + *target = *source; + /* target and remaining are updated below. */ + } + source++; + target++; + remaining--; + } + + /* Write the terminating NUL character. */ + *target = '\0'; + + return target - to; +} + +#ifdef ISC_PLATFORM_USETHREADS + +/*% + * Properly cleans up a list of database instances. + * This function is only used when the driver is compiled for + * multithreaded operation. + */ +static void +postgres_destroy_dblist(db_list_t *dblist) +{ + + dbinstance_t *ndbi = NULL; + dbinstance_t *dbi = NULL; + + /* get the first DBI in the list */ + ndbi = ISC_LIST_HEAD(*dblist); + + /* loop through the list */ + while (ndbi != NULL) { + dbi = ndbi; + /* get the next DBI in the list */ + ndbi = ISC_LIST_NEXT(dbi, link); + /* release DB connection */ + if (dbi->dbconn != NULL) + PQfinish((PGconn *) dbi->dbconn); + /* release all memory that comprised a DBI */ + destroy_sqldbinstance(dbi); + } + /* release memory for the list structure */ + isc_mem_put(ns_g_mctx, dblist, sizeof(db_list_t)); +} + +/*% + * Loops through the list of DB instances, attempting to lock + * on the mutex. If successful, the DBI is reserved for use + * and the thread can perform queries against the database. + * If the lock fails, the next one in the list is tried. + * looping continues until a lock is obtained, or until + * the list has been searched dbc_search_limit times. + * This function is only used when the driver is compiled for + * multithreaded operation. + */ + +static dbinstance_t * +postgres_find_avail_conn(db_list_t *dblist) +{ + dbinstance_t *dbi = NULL; + dbinstance_t *head; + int count = 0; + + /* get top of list */ + head = dbi = ISC_LIST_HEAD(*dblist); + + /* loop through list */ + while (count < dbc_search_limit) { + /* try to lock on the mutex */ + if (isc_mutex_trylock(&dbi->instance_lock) == ISC_R_SUCCESS) + return dbi; /* success, return the DBI for use. */ + + /* not successful, keep trying */ + dbi = ISC_LIST_NEXT(dbi, link); + + /* check to see if we have gone to the top of the list. */ + if (dbi == NULL) { + count++; + dbi = head; + } + } + isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_DLZ, ISC_LOG_INFO, + "Postgres driver unable to find available connection " + "after searching %d times", + count); + return NULL; +} + +#endif /* ISC_PLATFORM_USETHREADS */ + +/*% + * Allocates memory for a new string, and then constructs the new + * string by "escaping" the input string. The new string is + * safe to be used in queries. This is necessary because we cannot + * be sure of what types of strings are passed to us, and we don't + * want special characters in the string causing problems. + */ + +static char * +postgres_escape_string(const char *instr) { + + char *outstr; + unsigned int len; + + if (instr == NULL) + return NULL; + + len = strlen(instr); + + outstr = isc_mem_allocate(ns_g_mctx ,(2 * len * sizeof(char)) + 1); + if (outstr == NULL) + return NULL; + + postgres_makesafe(outstr, instr, len); + /* PQescapeString(outstr, instr, len); */ + + return outstr; +} + +/*% + * This function is the real core of the driver. Zone, record + * and client strings are passed in (or NULL is passed if the + * string is not available). The type of query we want to run + * is indicated by the query flag, and the dbdata object is passed + * passed in to. dbdata really holds either: + * 1) a list of database instances (in multithreaded mode) OR + * 2) a single database instance (in single threaded mode) + * The function will construct the query and obtain an available + * database instance (DBI). It will then run the query and hopefully + * obtain a result set. Postgres is nice, in that once the result + * set is returned, we can make the db connection available for another + * thread to use, while this thread continues on. So, the DBI is made + * available ASAP by unlocking the instance_lock after we have cleaned + * it up properly. + */ +static isc_result_t +postgres_get_resultset(const char *zone, const char *record, + const char *client, unsigned int query, + void *dbdata, PGresult **rs) +{ + isc_result_t result; + dbinstance_t *dbi = NULL; + char *querystring = NULL; + unsigned int i = 0; + unsigned int j = 0; + + /* temporarily get a unique thread # */ + unsigned int dlz_thread_num = 1+(int) (1000.0*rand()/(RAND_MAX+1.0)); + + REQUIRE(*rs == NULL); + +#if 0 + /* temporary logging message */ + isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_DLZ, ISC_LOG_ERROR, + "%d Getting DBI", dlz_thread_num); +#endif + + /* get db instance / connection */ +#ifdef ISC_PLATFORM_USETHREADS + + /* find an available DBI from the list */ + dbi = postgres_find_avail_conn((db_list_t *) dbdata); + +#else /* ISC_PLATFORM_USETHREADS */ + + /* + * only 1 DBI - no need to lock instance lock either + * only 1 thread in the whole process, no possible contention. + */ + dbi = (dbinstance_t *) dbdata; + +#endif /* ISC_PLATFORM_USETHREADS */ + +#if 0 + /* temporary logging message */ + isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_DLZ, ISC_LOG_ERROR, + "%d Got DBI - checking query", dlz_thread_num); +#endif + + /* if DBI is null, can't do anything else */ + if (dbi == NULL) { + result = ISC_R_FAILURE; + goto cleanup; + } + + /* what type of query are we going to run? */ + switch(query) { + case ALLNODES: + /* + * if the query was not passed in from the config file + * then we can't run it. return not_implemented, so + * it's like the code for that operation was never + * built into the driver.... AHHH flexibility!!! + */ + if (dbi->allnodes_q == NULL) { + result = ISC_R_NOTIMPLEMENTED; + goto cleanup; + } + break; + case ALLOWXFR: + /* same as comments as ALLNODES */ + if (dbi->allowxfr_q == NULL) { + result = ISC_R_NOTIMPLEMENTED; + goto cleanup; + } + break; + case AUTHORITY: + /* same as comments as ALLNODES */ + if (dbi->authority_q == NULL) { + result = ISC_R_NOTIMPLEMENTED; + goto cleanup; + } + break; + case FINDZONE: + /* this is required. It's the whole point of DLZ! */ + if (dbi->findzone_q == NULL) { + isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_DLZ, ISC_LOG_DEBUG(2), + "No query specified for findzone. " + "Findzone requires a query"); + result = ISC_R_FAILURE; + goto cleanup; + } + break; + case LOOKUP: + /* this is required. It's also a major point of DLZ! */ + if (dbi->lookup_q == NULL) { + isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_DLZ, ISC_LOG_DEBUG(2), + "No query specified for lookup. " + "Lookup requires a query"); + result = ISC_R_FAILURE; + goto cleanup; + } + break; + default: + /* + * this should never happen. If it does, the code is + * screwed up! + */ + UNEXPECTED_ERROR(__FILE__, __LINE__, + "Incorrect query flag passed to " + "postgres_get_resultset"); + result = ISC_R_UNEXPECTED; + goto cleanup; + } + +#if 0 + /* temporary logging message */ + isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_DLZ, ISC_LOG_ERROR, + "%d checked query", dlz_thread_num); +#endif + + /* + * was a zone string passed? If so, make it safe for use in + * queries. + */ + if (zone != NULL) { + dbi->zone = postgres_escape_string(zone); + if (dbi->zone == NULL) { + result = ISC_R_NOMEMORY; + goto cleanup; + } + } else { /* no string passed, set the string pointer to NULL */ + dbi->zone = NULL; + } + +#if 0 + /* temporary logging message */ + isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_DLZ, ISC_LOG_ERROR, + "%d did zone", dlz_thread_num); +#endif + + /* + * was a record string passed? If so, make it safe for use in + * queries. + */ + if (record != NULL) { + dbi->record = postgres_escape_string(record); + if (dbi->record == NULL) { + result = ISC_R_NOMEMORY; + goto cleanup; + } + } else { /* no string passed, set the string pointer to NULL */ + dbi->record = NULL; + } + + +#if 0 + /* temporary logging message */ + isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_DLZ, ISC_LOG_ERROR, + "%d did record", dlz_thread_num); +#endif + + /* + * was a client string passed? If so, make it safe for use in + * queries. + */ + if (client != NULL) { + dbi->client = postgres_escape_string(client); + if (dbi->client == NULL) { + result = ISC_R_NOMEMORY; + goto cleanup; + } + } else { /* no string passed, set the string pointer to NULL */ + dbi->client = NULL; + } + +#if 0 + /* temporary logging message */ + isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_DLZ, ISC_LOG_ERROR, + "%d did client", dlz_thread_num); +#endif + + /* + * what type of query are we going to run? + * this time we build the actual query to run. + */ + switch(query) { + case ALLNODES: + querystring = build_querystring(ns_g_mctx, dbi->allnodes_q); + break; + case ALLOWXFR: + querystring = build_querystring(ns_g_mctx, dbi->allowxfr_q); + break; + case AUTHORITY: + querystring = build_querystring(ns_g_mctx, dbi->authority_q); + break; + case FINDZONE: + querystring = build_querystring(ns_g_mctx, dbi->findzone_q); + break; + case LOOKUP: + querystring = build_querystring(ns_g_mctx, dbi->lookup_q); + break; + default: + /* + * this should never happen. If it does, the code is + * screwed up! + */ + UNEXPECTED_ERROR(__FILE__, __LINE__, + "Incorrect query flag passed to " + "postgres_get_resultset"); + result = ISC_R_UNEXPECTED; + goto cleanup; + } + +#if 0 + /* temporary logging message */ + isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_DLZ, ISC_LOG_ERROR, + "%d built query", dlz_thread_num); +#endif + + /* if the querystring is null, Bummer, outta RAM. UPGRADE TIME!!! */ + if (querystring == NULL) { + result = ISC_R_NOMEMORY; + goto cleanup; + } + +#if 0 + /* temporary logging message */ + isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_DLZ, ISC_LOG_ERROR, + "%d query is '%s'", dlz_thread_num, querystring); +#endif + + /* + * output the full query string during debug so we can see + * what lame error the query has. + */ + isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_DLZ, ISC_LOG_DEBUG(1), + "\nQuery String: %s\n", querystring); + + /* attempt query up to 3 times. */ + for (j=0; j < 3; j++) { +#if 0 + /* temporary logging message */ + isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_DLZ, ISC_LOG_ERROR, + "%d executing query for %d time", + dlz_thread_num, j); +#endif + /* try to get result set */ + *rs = PQexec((PGconn *)dbi->dbconn, querystring ); + result = ISC_R_SUCCESS; + /* + * if result set is null, reset DB connection, max 3 + * attempts. + */ + for (i=0; *rs == NULL && i < 3; i++) { +#if 0 + /* temporary logging message */ + isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_DLZ, ISC_LOG_ERROR, + "%d resetting connection", + dlz_thread_num); +#endif + result = ISC_R_FAILURE; + PQreset((PGconn *) dbi->dbconn); + /* connection ok, break inner loop */ + if (PQstatus((PGconn *) dbi->dbconn) == CONNECTION_OK) + break; + } + /* result set ok, break outter loop */ + if (PQresultStatus(*rs) == PGRES_TUPLES_OK) { +#if 0 + /* temporary logging message */ + isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_DLZ, ISC_LOG_ERROR, + "%d rs ok", dlz_thread_num); +#endif + break; + } else { + /* we got a result set object, but it's not right. */ +#if 0 + /* temporary logging message */ + isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_DLZ, ISC_LOG_ERROR, + "%d clearing rs", dlz_thread_num); +#endif + PQclear(*rs); /* get rid of it */ + /* in case this was the last attempt */ + result = ISC_R_FAILURE; + } + } + + cleanup: + /* it's always good to cleanup after yourself */ + +#if 0 + /* temporary logging message */ + isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_DLZ, ISC_LOG_ERROR, + "%d cleaning up", dlz_thread_num); +#endif + + /* if we couldn't even allocate DBI, just return NULL */ + if (dbi == NULL) + return ISC_R_FAILURE; + + /* free dbi->zone string */ + if (dbi->zone != NULL) + isc_mem_free(ns_g_mctx, dbi->zone); + + /* free dbi->record string */ + if (dbi->record != NULL) + isc_mem_free(ns_g_mctx, dbi->record); + + /* free dbi->client string */ + if (dbi->client != NULL) + isc_mem_free(ns_g_mctx, dbi->client); + +#ifdef ISC_PLATFORM_USETHREADS + +#if 0 + /* temporary logging message */ + isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_DLZ, ISC_LOG_ERROR, + "%d unlocking mutex", dlz_thread_num); +#endif + + /* release the lock so another thread can use this dbi */ + isc_mutex_unlock(&dbi->instance_lock); + +#endif /* ISC_PLATFORM_USETHREADS */ + + /* release query string */ + if (querystring != NULL) + isc_mem_free(ns_g_mctx, querystring ); + +#if 0 + /* temporary logging message */ + isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_DLZ, ISC_LOG_ERROR, + "%d returning", dlz_thread_num); +#endif + + /* return result */ + return result; +} + +/*% + * The processing of result sets for lookup and authority are + * exactly the same. So that functionality has been moved + * into this function to minimize code. + */ + +static isc_result_t +postgres_process_rs(dns_sdlzlookup_t *lookup, PGresult *rs) +{ + isc_result_t result; + unsigned int i; + unsigned int rows; + unsigned int fields; + unsigned int j; + unsigned int len; + char *tmpString; + char *endp; + int ttl; + + rows = PQntuples(rs); /* how many rows in result set */ + fields = PQnfields(rs); /* how many columns in result set */ + for (i=0; i < rows; i++) { + switch(fields) { + case 1: + /* + * one column in rs, it's the data field. use + * default type of A record, and default TTL + * of 86400 + */ + result = dns_sdlz_putrr(lookup, "a", 86400, + PQgetvalue(rs, i, 0)); + break; + case 2: + /* two columns, data field, and data type. + * use default TTL of 86400. + */ + result = dns_sdlz_putrr(lookup, PQgetvalue(rs, i, 0), + 86400, PQgetvalue(rs, i, 1)); + break; + case 3: + /* three columns, all data no defaults. + * convert text to int, make sure it worked + * right. + */ + ttl = strtol(PQgetvalue(rs, i, 0), &endp, 10); + if (*endp != '\0' || ttl < 0) { + isc_log_write(dns_lctx, + DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_DLZ, ISC_LOG_ERROR, + "Postgres driver ttl must be " + "a positive number"); + } + result = dns_sdlz_putrr(lookup, PQgetvalue(rs, i, 1), + ttl, PQgetvalue(rs, i, 2)); + break; + default: + /* + * more than 3 fields, concatenate the last + * ones together. figure out how long to make + * string + */ + for (j=2, len=0; j < fields; j++) { + len += strlen(PQgetvalue(rs, i, j)) + 1; + } + /* + * allocate string memory, allow for NULL to + * term string + */ + tmpString = isc_mem_allocate(ns_g_mctx, len + 1); + if (tmpString == NULL) { + /* major bummer, need more ram */ + isc_log_write(dns_lctx, + DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_DLZ, ISC_LOG_ERROR, + "Postgres driver unable to " + "allocate memory for " + "temporary string"); + PQclear(rs); + return (ISC_R_FAILURE); /* Yeah, I'd say! */ + } + /* copy field to tmpString */ + strcpy(tmpString, PQgetvalue(rs, i, 2)); + /* + * concat the rest of fields together, space + * between each one. + */ + for (j=3; j < fields; j++) { + strcat(tmpString, " "); + strcat(tmpString, PQgetvalue(rs, i, j)); + } + /* convert text to int, make sure it worked right */ + ttl = strtol(PQgetvalue(rs, i, 0), &endp, 10); + if (*endp != '\0' || ttl < 0) { + isc_log_write(dns_lctx, + DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_DLZ, ISC_LOG_ERROR, + "Postgres driver ttl must be " + "a postive number"); + } + /* ok, now tell Bind about it. */ + result = dns_sdlz_putrr(lookup, PQgetvalue(rs, i, 1), + ttl, tmpString); + /* done, get rid of this thing. */ + isc_mem_free(ns_g_mctx, tmpString); + } + /* I sure hope we were successful */ + if (result != ISC_R_SUCCESS) { + /* nope, get rid of the Result set, and log a msg */ + PQclear(rs); + isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_DLZ, ISC_LOG_ERROR, + "dns_sdlz_putrr returned error. " + "Error code was: %s", + isc_result_totext(result)); + return (ISC_R_FAILURE); + } + } + + /* free result set memory */ + PQclear(rs); + + /* if we did return results, we are successful */ + if (rows > 0) + return (ISC_R_SUCCESS); + + /* empty result set, no data found */ + return (ISC_R_NOTFOUND); +} + +/* + * SDLZ interface methods + */ + +/*% determine if the zone is supported by (in) the database */ + +static isc_result_t +postgres_findzone(void *driverarg, void *dbdata, const char *name) +{ + isc_result_t result; + PGresult *rs = NULL; + unsigned int rows; + UNUSED(driverarg); + + /* run the query and get the result set from the database. */ + result = postgres_get_resultset(name, NULL, NULL, + FINDZONE, dbdata, &rs); + /* if we didn't get a result set, log an err msg. */ + if (result != ISC_R_SUCCESS) { + if (rs != NULL) + PQclear(rs); + isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_DLZ, ISC_LOG_ERROR, + "Postgres driver unable to return " + "result set for findzone query"); + return (ISC_R_FAILURE); + } + /* count how many rows in result set */ + rows = PQntuples(rs); + /* get rid of result set, we are done with it. */ + PQclear(rs); + + /* if we returned any rows, zone is supported. */ + if (rows > 0) + return (ISC_R_SUCCESS); + + /* no rows returned, zone is not supported. */ + return (ISC_R_NOTFOUND); +} + +/*% Determine if the client is allowed to perform a zone transfer */ +static isc_result_t +postgres_allowzonexfr(void *driverarg, void *dbdata, const char *name, + const char *client) +{ + isc_result_t result; + PGresult *rs = NULL; + unsigned int rows; + UNUSED(driverarg); + + /* first check if the zone is supported by the database. */ + result = postgres_findzone(driverarg, dbdata, name); + if (result != ISC_R_SUCCESS) + return (ISC_R_NOTFOUND); + + /* + * if we get to this point we know the zone is supported by + * the database the only questions now are is the zone + * transfer is allowed for this client and did the config file + * have an allow zone xfr query. + * + * Run our query, and get a result set from the database. + */ + result = postgres_get_resultset(name, NULL, client, + ALLOWXFR, dbdata, &rs); + /* if we get "not implemented", send it along. */ + if (result == ISC_R_NOTIMPLEMENTED) + return result; + /* if we didn't get a result set, log an err msg. */ + if (result != ISC_R_SUCCESS) { + if (rs != NULL) + PQclear(rs); + isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_DLZ, ISC_LOG_ERROR, + "Postgres driver unable to return " + "result set for allow xfr query"); + return (ISC_R_FAILURE); + } + /* count how many rows in result set */ + rows = PQntuples(rs); + /* get rid of result set, we are done with it. */ + PQclear(rs); + + /* if we returned any rows, zone xfr is allowed. */ + if (rows > 0) + return (ISC_R_SUCCESS); + + /* no rows returned, zone xfr not allowed */ + return (ISC_R_NOPERM); +} + +/*% + * If the client is allowed to perform a zone transfer, the next order of + * business is to get all the nodes in the zone, so bind can respond to the + * query. + */ +static isc_result_t +postgres_allnodes(const char *zone, void *driverarg, void *dbdata, + dns_sdlzallnodes_t *allnodes) +{ + isc_result_t result; + PGresult *rs = NULL; + unsigned int i; + unsigned int rows; + unsigned int fields; + unsigned int j; + unsigned int len; + char *tmpString; + char *endp; + int ttl; + + UNUSED(driverarg); + + /* run the query and get the result set from the database. */ + result = postgres_get_resultset(zone, NULL, NULL, + ALLNODES, dbdata, &rs); + /* if we get "not implemented", send it along */ + if (result == ISC_R_NOTIMPLEMENTED) + return result; + /* if we didn't get a result set, log an err msg. */ + if (result != ISC_R_SUCCESS) { + if (rs != NULL) + PQclear(rs); + isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_DLZ, ISC_LOG_ERROR, + "Postgres driver unable to return " + "result set for all nodes query"); + return (ISC_R_FAILURE); + } + + rows = PQntuples(rs); /* how many rows in result set */ + fields = PQnfields(rs); /* how many columns in result set */ + for (i=0; i < rows; i++) { + if (fields < 4) { /* gotta have at least 4 columns */ + isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_DLZ, ISC_LOG_ERROR, + "Postgres driver too few fields " + "returned by all nodes query"); + } + /* convert text to int, make sure it worked right */ + ttl = strtol(PQgetvalue(rs, i, 0), &endp, 10); + if (*endp != '\0' || ttl < 0) { + isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_DLZ, ISC_LOG_ERROR, + "Postgres driver ttl must be " + "a postive number"); + } + if (fields == 4) { + /* tell Bind about it. */ + result = dns_sdlz_putnamedrr(allnodes, + PQgetvalue(rs, i, 2), + PQgetvalue(rs, i, 1), + ttl, + PQgetvalue(rs, i, 3)); + } else { + /* + * more than 4 fields, concatonat the last + * ones together. figure out how long to make + * string + */ + for (j=3, len=0; j < fields; j++) { + len += strlen(PQgetvalue(rs, i, j)) + 1; + } + /* allocate memory, allow for NULL to term string */ + tmpString = isc_mem_allocate(ns_g_mctx, len + 1); + if (tmpString == NULL) { /* we need more ram. */ + isc_log_write(dns_lctx, + DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_DLZ, ISC_LOG_ERROR, + "Postgres driver unable to " + "allocate memory for " + "temporary string"); + PQclear(rs); + return (ISC_R_FAILURE); + } + /* copy this field to tmpString */ + strcpy(tmpString, PQgetvalue(rs, i, 3)); + /* concatonate the rest, with spaces between */ + for (j=4; j < fields; j++) { + strcat(tmpString, " "); + strcat(tmpString, PQgetvalue(rs, i, j)); + } + /* tell Bind about it. */ + result = dns_sdlz_putnamedrr(allnodes, + PQgetvalue(rs, i, 2), + PQgetvalue(rs, i, 1), + ttl, tmpString); + isc_mem_free(ns_g_mctx, tmpString); + } + /* if we weren't successful, log err msg */ + if (result != ISC_R_SUCCESS) { + PQclear(rs); + isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_DLZ, ISC_LOG_ERROR, + "dns_sdlz_putnamedrr returned error. " + "Error code was: %s", + isc_result_totext(result)); + return (ISC_R_FAILURE); + } + } + + /* free result set memory */ + PQclear(rs); + + /* if we did return results, we are successful */ + if (rows > 0) + return (ISC_R_SUCCESS); + + /* empty result set, no data found */ + return (ISC_R_NOTFOUND); +} + +/*% + * if the lookup function does not return SOA or NS records for the zone, + * use this function to get that information for Bind. + */ + +static isc_result_t +postgres_authority(const char *zone, void *driverarg, void *dbdata, + dns_sdlzlookup_t *lookup) +{ + isc_result_t result; + PGresult *rs = NULL; + + UNUSED(driverarg); + + /* run the query and get the result set from the database. */ + result = postgres_get_resultset(zone, NULL, NULL, + AUTHORITY, dbdata, &rs); + /* if we get "not implemented", send it along */ + if (result == ISC_R_NOTIMPLEMENTED) + return result; + /* if we didn't get a result set, log an err msg. */ + if (result != ISC_R_SUCCESS) { + if (rs != NULL) + PQclear(rs); + isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_DLZ, ISC_LOG_ERROR, + "Postgres driver unable to return " + "result set for authority query"); + return (ISC_R_FAILURE); + } + /* + * lookup and authority result sets are processed in the same + * manner postgres_process_rs does the job for both + * functions. + */ + return postgres_process_rs(lookup, rs); +} + +/*% if zone is supported, lookup up a (or multiple) record(s) in it */ +static isc_result_t +postgres_lookup(const char *zone, const char *name, void *driverarg, + void *dbdata, dns_sdlzlookup_t *lookup) +{ + isc_result_t result; + PGresult *rs = NULL; + + UNUSED(driverarg); + + /* run the query and get the result set from the database. */ + result = postgres_get_resultset(zone, name, NULL, LOOKUP, dbdata, &rs); + /* if we didn't get a result set, log an err msg. */ + if (result != ISC_R_SUCCESS) { + if (rs != NULL) + PQclear(rs); + isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_DLZ, ISC_LOG_ERROR, + "Postgres driver unable to " + "return result set for lookup query"); + return (ISC_R_FAILURE); + } + /* + * lookup and authority result sets are processed in the same + * manner postgres_process_rs does the job for both functions. + */ + return postgres_process_rs(lookup, rs); +} + +/*% + * create an instance of the driver. Remember, only 1 copy of the driver's + * code is ever loaded, the driver has to remember which context it's + * operating in. This is done via use of the dbdata argument which is + * passed into all query functions. + */ +static isc_result_t +postgres_create(const char *dlzname, unsigned int argc, char *argv[], + void *driverarg, void **dbdata) +{ + isc_result_t result; + dbinstance_t *dbi = NULL; + unsigned int j; + +#ifdef ISC_PLATFORM_USETHREADS + /* if multi-threaded, we need a few extra variables. */ + int dbcount; + db_list_t *dblist = NULL; + int i; + char *endp; + +#endif /* ISC_PLATFORM_USETHREADS */ + + UNUSED(driverarg); + UNUSED(dlzname); + +/* seed random # generator */ + srand( (unsigned)time( NULL ) ); + + +#ifdef ISC_PLATFORM_USETHREADS + /* if debugging, let user know we are multithreaded. */ + isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_DLZ, ISC_LOG_DEBUG(1), + "Postgres driver running multithreaded"); +#else /* ISC_PLATFORM_USETHREADS */ + /* if debugging, let user know we are single threaded. */ + isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_DLZ, ISC_LOG_DEBUG(1), + "Postgres driver running single threaded"); +#endif /* ISC_PLATFORM_USETHREADS */ + + /* verify we have at least 5 arg's passed to the driver */ + if (argc < 5) { + isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_DLZ, ISC_LOG_ERROR, + "Postgres driver requires at least " + "4 command line args."); + return (ISC_R_FAILURE); + } + + /* no more than 8 arg's should be passed to the driver */ + if (argc > 8) { + isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_DLZ, ISC_LOG_ERROR, + "Postgres driver cannot accept more than " + "7 command line args."); + return (ISC_R_FAILURE); + } + + /* multithreaded build can have multiple DB connections */ +#ifdef ISC_PLATFORM_USETHREADS + + /* check how many db connections we should create */ + dbcount = strtol(argv[1], &endp, 10); + if (*endp != '\0' || dbcount < 0) { + isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_DLZ, ISC_LOG_ERROR, + "Postgres driver database connection count " + "must be positive."); + return (ISC_R_FAILURE); + } + + /* allocate memory for database connection list */ + dblist = isc_mem_get(ns_g_mctx, sizeof(db_list_t)); + if (dblist == NULL) + return (ISC_R_NOMEMORY); + + /* initialize DB connection list */ + ISC_LIST_INIT(*dblist); + + /* + * create the appropriate number of database instances (DBI) + * append each new DBI to the end of the list + */ + for (i=0; i < dbcount; i++) { + +#endif /* ISC_PLATFORM_USETHREADS */ + + /* how many queries were passed in from config file? */ + switch(argc) { + case 5: + result = build_sqldbinstance(ns_g_mctx, NULL, NULL, + NULL, argv[3], argv[4], + NULL, &dbi); + break; + case 6: + result = build_sqldbinstance(ns_g_mctx, NULL, NULL, + argv[5], argv[3], argv[4], + NULL, &dbi); + break; + case 7: + result = build_sqldbinstance(ns_g_mctx, argv[6], NULL, + argv[5], argv[3], argv[4], + NULL, &dbi); + break; + case 8: + result = build_sqldbinstance(ns_g_mctx, argv[6], + argv[7], argv[5], argv[3], + argv[4], NULL, &dbi); + break; + default: + /* not really needed, should shut up compiler. */ + result = ISC_R_FAILURE; + } + + + if (result == ISC_R_SUCCESS) { + isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_DLZ, ISC_LOG_DEBUG(2), + "Postgres driver created database " + "instance object."); + } else { /* unsuccessful?, log err msg and cleanup. */ + isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_DLZ, ISC_LOG_ERROR, + "Postgres driver could not create " + "database instance object."); + goto cleanup; + } + +#ifdef ISC_PLATFORM_USETHREADS + + /* when multithreaded, build a list of DBI's */ + ISC_LINK_INIT(dbi, link); + ISC_LIST_APPEND(*dblist, dbi, link); + +#endif + + /* create and set db connection */ + dbi->dbconn = PQconnectdb(argv[2]); + /* + * if db connection cannot be created, log err msg and + * cleanup. + */ + if (dbi->dbconn == NULL) { + isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_DLZ, ISC_LOG_ERROR, + "Postgres driver could not allocate " + "memory for database connection"); + goto cleanup; + } + + /* if we cannot connect the first time, try 3 more times. */ + for (j = 0; + PQstatus((PGconn *) dbi->dbconn) != CONNECTION_OK && + j < 3; + j++) + PQreset((PGconn *) dbi->dbconn); + + +#ifdef ISC_PLATFORM_USETHREADS + + /* + * if multi threaded, let user know which connection + * failed. user could be attempting to create 10 db + * connections and for some reason the db backend only + * allows 9 + */ + if (PQstatus((PGconn *) dbi->dbconn) != CONNECTION_OK) { + isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_DLZ, ISC_LOG_ERROR, + "Postgres driver failed to create " + "database connection number %u " + "after 4 attempts", + i + 1); + goto cleanup; + } + + /* set DBI = null for next loop through. */ + dbi = NULL; + } /* end for loop */ + + /* set dbdata to the list we created. */ + *dbdata = dblist; + +#else /* ISC_PLATFORM_USETHREADS */ + /* if single threaded, just let user know we couldn't connect. */ + if (PQstatus((PGconn *) dbi->dbconn) != CONNECTION_OK) { + isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_DLZ, ISC_LOG_ERROR, + "Postgres driver failed to create database " + "connection after 4 attempts"); + goto cleanup; + } + + /* + * single threaded build can only use 1 db connection, return + * it via dbdata + */ + *dbdata = dbi; + +#endif /* ISC_PLATFORM_USETHREADS */ + + /* hey, we got through all of that ok, return success. */ + return(ISC_R_SUCCESS); + + cleanup: + +#ifdef ISC_PLATFORM_USETHREADS + /* + * if multithreaded, we could fail because only 1 connection + * couldn't be made. We should cleanup the other successful + * connections properly. + */ + postgres_destroy_dblist(dblist); + +#else /* ISC_PLATFORM_USETHREADS */ + if (dbi != NULL) + destroy_sqldbinstance(dbi); + +#endif /* ISC_PLATFORM_USETHREADS */ + return(ISC_R_FAILURE); +} + +/*% + * destroy an instance of the driver. Remember, only 1 copy of the driver's + * code is ever loaded, the driver has to remember which context it's + * operating in. This is done via use of the dbdata argument. + * so we really only need to clean it up since we are not using driverarg. + */ +static void +postgres_destroy(void *driverarg, void *dbdata) +{ + +#ifdef ISC_PLATFORM_USETHREADS + + UNUSED(driverarg); + /* cleanup the list of DBI's */ + postgres_destroy_dblist((db_list_t *) dbdata); + +#else /* ISC_PLATFORM_USETHREADS */ + + dbinstance_t *dbi; + + UNUSED(driverarg); + + dbi = (dbinstance_t *) dbdata; + + /* release DB connection */ + if (dbi->dbconn != NULL) + PQfinish((PGconn *) dbi->dbconn); + + /* destroy single DB instance */ + destroy_sqldbinstance(dbi); + +#endif /* ISC_PLATFORM_USETHREADS */ +} + +/* pointers to all our runtime methods. */ +/* this is used during driver registration */ +/* i.e. in dlz_postgres_init below. */ +static dns_sdlzmethods_t dlz_postgres_methods = { + postgres_create, + postgres_destroy, + postgres_findzone, + postgres_lookup, + postgres_authority, + postgres_allnodes, + postgres_allowzonexfr +}; + +/*% + * Wrapper around dns_sdlzregister(). + */ +isc_result_t +dlz_postgres_init(void) { + isc_result_t result; + + /* + * Write debugging message to log + */ + isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_DLZ, ISC_LOG_DEBUG(2), + "Registering DLZ postgres driver."); + + /* + * Driver is always threadsafe. When multithreaded all + * functions use multithreaded code. When not multithreaded, + * all functions can only be entered once, but only 1 thread + * of operation is available in Bind. So everything is still + * threadsafe. + */ + result = dns_sdlzregister("postgres", &dlz_postgres_methods, NULL, + DNS_SDLZFLAG_RELATIVEOWNER | + DNS_SDLZFLAG_RELATIVERDATA | + DNS_SDLZFLAG_THREADSAFE, + ns_g_mctx, &dlz_postgres); + /* if we can't register the driver, there are big problems. */ + if (result != ISC_R_SUCCESS) { + UNEXPECTED_ERROR(__FILE__, __LINE__, + "dns_sdlzregister() failed: %s", + isc_result_totext(result)); + result = ISC_R_UNEXPECTED; + } + + + return result; +} + +/*% + * Wrapper around dns_sdlzunregister(). + */ +void +dlz_postgres_clear(void) { + + /* + * Write debugging message to log + */ + isc_log_write(dns_lctx, DNS_LOGCATEGORY_DATABASE, + DNS_LOGMODULE_DLZ, ISC_LOG_DEBUG(2), + "Unregistering DLZ postgres driver."); + + /* unregister the driver. */ + if (dlz_postgres != NULL) + dns_sdlzunregister(&dlz_postgres); +} + +#endif |