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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 16:16:13 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 16:16:13 +0000 |
commit | e90fcc54809db2591dc083f43ef54c6ec8c60847 (patch) | |
tree | f20bc206c3c2d5d59d37c46c5cf5d53a20642556 /src/lookups/redis.c | |
parent | Initial commit. (diff) | |
download | exim4-e90fcc54809db2591dc083f43ef54c6ec8c60847.tar.xz exim4-e90fcc54809db2591dc083f43ef54c6ec8c60847.zip |
Adding upstream version 4.96.upstream/4.96upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | src/lookups/redis.c | 471 |
1 files changed, 471 insertions, 0 deletions
diff --git a/src/lookups/redis.c b/src/lookups/redis.c new file mode 100644 index 0000000..9c8559c --- /dev/null +++ b/src/lookups/redis.c @@ -0,0 +1,471 @@ +/************************************************* +* Exim - an Internet mail transport agent * +*************************************************/ + +/* Copyright (c) The Exim Maintainers 2020 - 2022 */ +/* Copyright (c) University of Cambridge 1995 - 2018 */ +/* See the file NOTICE for conditions of use and distribution. */ + +#include "../exim.h" + +#ifdef LOOKUP_REDIS + +#include "lf_functions.h" + +#include <hiredis/hiredis.h> + +#ifndef nele +# define nele(arr) (sizeof(arr) / sizeof(*arr)) +#endif + +/* Structure and anchor for caching connections. */ +typedef struct redis_connection { + struct redis_connection *next; + uschar *server; + redisContext *handle; +} redis_connection; + +static redis_connection *redis_connections = NULL; + + +static void * +redis_open(const uschar * filename, uschar ** errmsg) +{ +return (void *)(1); +} + + +void +redis_tidy(void) +{ +redis_connection *cn; + +/* XXX: Not sure how often this is called! + Guess its called after every lookup which probably would mean to just + not use the _tidy() function at all and leave with exim exiting to + GC connections! */ + +while ((cn = redis_connections)) + { + redis_connections = cn->next; + DEBUG(D_lookup) debug_printf_indent("close REDIS connection: %s\n", cn->server); + redisFree(cn->handle); + } +} + + +/* This function is called from the find entry point to do the search for a +single server. + + Arguments: + query the query string + server the server string + resultptr where to store the result + errmsg where to point an error message + defer_break TRUE if no more servers are to be tried after DEFER + do_cache set false if data is changed + opts options + + The server string is of the form "host/dbnumber/password". The host can be + host:port. This string is in a nextinlist temporary buffer, so can be + overwritten. + + Returns: OK, FAIL, or DEFER +*/ + +static int +perform_redis_search(const uschar *command, uschar *server, uschar **resultptr, + uschar **errmsg, BOOL *defer_break, uint *do_cache, const uschar * opts) +{ +redisContext *redis_handle = NULL; /* Keep compilers happy */ +redisReply *redis_reply = NULL; +redisReply *entry = NULL; +redisReply *tentry = NULL; +redis_connection *cn; +int yield = DEFER; +int i, j; +gstring * result = NULL; +uschar *server_copy = NULL; +uschar *sdata[3]; + +/* Disaggregate the parameters from the server argument. +The order is host:port(socket) +We can write to the string, since it is in a nextinlist temporary buffer. +This copy is also used for debugging output. */ + +memset(sdata, 0, sizeof(sdata)) /* Set all to NULL */; +for (int i = 2; i > 0; i--) + { + uschar *pp = Ustrrchr(server, '/'); + + if (!pp) + { + *errmsg = string_sprintf("incomplete Redis server data: %s", + i == 2 ? server : server_copy); + *defer_break = TRUE; + return DEFER; + } + *pp++ = 0; + sdata[i] = pp; + if (i == 2) server_copy = string_copy(server); /* sans password */ + } +sdata[0] = server; /* What's left at the start */ + +/* If the database or password is an empty string, set it NULL */ +if (sdata[1][0] == 0) sdata[1] = NULL; +if (sdata[2][0] == 0) sdata[2] = NULL; + +/* See if we have a cached connection to the server */ + +for (cn = redis_connections; cn; cn = cn->next) + if (Ustrcmp(cn->server, server_copy) == 0) + { + redis_handle = cn->handle; + break; + } + +if (!cn) + { + uschar *p; + uschar *socket = NULL; + int port = 0; + /* int redis_err = REDIS_OK; */ + + if ((p = Ustrchr(sdata[0], '('))) + { + *p++ = 0; + socket = p; + while (*p != 0 && *p != ')') p++; + *p = 0; + } + + if ((p = Ustrchr(sdata[0], ':'))) + { + *p++ = 0; + port = Uatoi(p); + } + else + port = Uatoi("6379"); + + if (Ustrchr(server, '/')) + { + *errmsg = string_sprintf("unexpected slash in Redis server hostname: %s", + sdata[0]); + *defer_break = TRUE; + return DEFER; + } + + DEBUG(D_lookup) + debug_printf_indent("REDIS new connection: host=%s port=%d socket=%s database=%s\n", + sdata[0], port, socket, sdata[1]); + + /* Get store for a new handle, initialize it, and connect to the server */ + /* XXX: Use timeouts ? */ + redis_handle = + socket ? redisConnectUnix(CCS socket) : redisConnect(CCS server, port); + if (!redis_handle) + { + *errmsg = US"REDIS connection failed"; + *defer_break = FALSE; + goto REDIS_EXIT; + } + + /* Add the connection to the cache */ + cn = store_get(sizeof(redis_connection), GET_UNTAINTED); + cn->server = server_copy; + cn->handle = redis_handle; + cn->next = redis_connections; + redis_connections = cn; + } +else + { + DEBUG(D_lookup) + debug_printf_indent("REDIS using cached connection for %s\n", server_copy); +} + +/* Authenticate if there is a password */ +if(sdata[2]) + if (!(redis_reply = redisCommand(redis_handle, "AUTH %s", sdata[2]))) + { + *errmsg = string_sprintf("REDIS Authentication failed: %s\n", redis_handle->errstr); + *defer_break = FALSE; + goto REDIS_EXIT; + } + +/* Select the database if there is a dbnumber passed */ +if(sdata[1]) + { + if (!(redis_reply = redisCommand(redis_handle, "SELECT %s", sdata[1]))) + { + *errmsg = string_sprintf("REDIS: Selecting database=%s failed: %s\n", sdata[1], redis_handle->errstr); + *defer_break = FALSE; + goto REDIS_EXIT; + } + DEBUG(D_lookup) debug_printf_indent("REDIS: Selecting database=%s\n", sdata[1]); + } + +/* split string on whitespace into argv */ + { + uschar * argv[32]; + const uschar * s = command; + int siz, ptr, i; + uschar c; + + while (isspace(*s)) s++; + + for (i = 0; *s && i < nele(argv); i++) + { + gstring * g; + + for (g = NULL; (c = *s) && !isspace(c); s++) + if (c != '\\' || *++s) /* backslash protects next char */ + g = string_catn(g, s, 1); + argv[i] = string_from_gstring(g); + + DEBUG(D_lookup) debug_printf_indent("REDIS: argv[%d] '%s'\n", i, argv[i]); + while (isspace(*s)) s++; + } + + /* Run the command. We use the argv form rather than plain as that parses + into args by whitespace yet has no escaping mechanism. */ + + if (!(redis_reply = redisCommandArgv(redis_handle, i, CCSS argv, NULL))) + { + *errmsg = string_sprintf("REDIS: query failed: %s\n", redis_handle->errstr); + *defer_break = FALSE; + goto REDIS_EXIT; + } + } + +switch (redis_reply->type) + { + case REDIS_REPLY_ERROR: + *errmsg = string_sprintf("REDIS: lookup result failed: %s\n", redis_reply->str); + + /* trap MOVED cluster responses and follow them */ + if (Ustrncmp(redis_reply->str, "MOVED", 5) == 0) + { + DEBUG(D_lookup) + debug_printf_indent("REDIS: cluster redirect %s\n", redis_reply->str); + /* follow redirect + This is cheating, we simply set defer_break = FALSE to move on to + the next server in the redis_servers list */ + *defer_break = FALSE; + return DEFER; + } else { + *defer_break = TRUE; + } + *do_cache = 0; + goto REDIS_EXIT; + /* NOTREACHED */ + + case REDIS_REPLY_NIL: + DEBUG(D_lookup) + debug_printf_indent("REDIS: query was not one that returned any data\n"); + result = string_catn(result, US"", 1); + *do_cache = 0; + goto REDIS_EXIT; + /* NOTREACHED */ + + case REDIS_REPLY_INTEGER: + result = string_cat(result, redis_reply->integer != 0 ? US"true" : US"false"); + break; + + case REDIS_REPLY_STRING: + case REDIS_REPLY_STATUS: + result = string_catn(result, US redis_reply->str, redis_reply->len); + break; + + case REDIS_REPLY_ARRAY: + + /* NOTE: For now support 1 nested array result. If needed a limitless + result can be parsed */ + + for (int i = 0; i < redis_reply->elements; i++) + { + entry = redis_reply->element[i]; + + if (result) + result = string_catn(result, US"\n", 1); + + switch (entry->type) + { + case REDIS_REPLY_INTEGER: + result = string_fmt_append(result, "%d", entry->integer); + break; + case REDIS_REPLY_STRING: + result = string_catn(result, US entry->str, entry->len); + break; + case REDIS_REPLY_ARRAY: + for (int j = 0; j < entry->elements; j++) + { + tentry = entry->element[j]; + + if (result) + result = string_catn(result, US"\n", 1); + + switch (tentry->type) + { + case REDIS_REPLY_INTEGER: + result = string_fmt_append(result, "%d", tentry->integer); + break; + case REDIS_REPLY_STRING: + result = string_catn(result, US tentry->str, tentry->len); + break; + case REDIS_REPLY_ARRAY: + DEBUG(D_lookup) + debug_printf_indent("REDIS: result has nesting of arrays which" + " is not supported. Ignoring!\n"); + break; + default: + DEBUG(D_lookup) debug_printf_indent( + "REDIS: result has unsupported type. Ignoring!\n"); + break; + } + } + break; + default: + DEBUG(D_lookup) debug_printf_indent("REDIS: query returned unsupported type\n"); + break; + } + } + break; + } + + +if (result) + gstring_release_unused(result); +else + { + yield = FAIL; + *errmsg = US"REDIS: no data found"; + } + +REDIS_EXIT: + +/* Free store for any result that was got; don't close the connection, +as it is cached. */ + +if (redis_reply) freeReplyObject(redis_reply); + +/* Non-NULL result indicates a successful result */ + +if (result) + { + *resultptr = string_from_gstring(result); + return OK; + } +else + { + DEBUG(D_lookup) debug_printf_indent("%s\n", *errmsg); + /* NOTE: Required to close connection since it needs to be reopened */ + return yield; /* FAIL or DEFER */ + } +} + + + +/************************************************* +* Find entry point * +*************************************************/ +/* + * See local README for interface description. The handle and filename + * arguments are not used. The code to loop through a list of servers while the + * query is deferred with a retryable error is now in a separate function that is + * shared with other noSQL lookups. + */ + +static int +redis_find(void * handle __attribute__((unused)), + const uschar * filename __attribute__((unused)), + const uschar * command, int length, uschar ** result, uschar ** errmsg, + uint * do_cache, const uschar * opts) +{ +return lf_sqlperform(US"Redis", US"redis_servers", redis_servers, command, + result, errmsg, do_cache, opts, perform_redis_search); +} + + + +/************************************************* +* Quote entry point * +*************************************************/ + +/* Prefix any whitespace, or backslash, with a backslash. +This is not a Redis thing but instead to let the argv splitting +we do to split on whitespace, yet provide means for getting +whitespace into an argument. + +Arguments: + s the string to be quoted + opt additional option text or NULL if none + idx lookup type index + +Returns: the processed string or NULL for a bad option +*/ + +static uschar * +redis_quote(uschar * s, uschar * opt, unsigned idx) +{ +int c, count = 0; +uschar * t = s, * quoted; + +if (opt) return NULL; /* No options recognized */ + +while ((c = *t++)) + if (isspace(c) || c == '\\') count++; + +t = quoted = store_get_quoted(Ustrlen(s) + count + 1, s, idx); + +while ((c = *s++)) + { + if (isspace(c) || c == '\\') *t++ = '\\'; + *t++ = c; + } + +*t = 0; +return quoted; +} + + +/************************************************* +* Version reporting entry point * +*************************************************/ +#include "../version.h" + +gstring * +redis_version_report(gstring * g) +{ +g = string_fmt_append(g, + "Library version: REDIS: Compile: %d [%d]\n", HIREDIS_MAJOR, HIREDIS_MINOR); +#ifdef DYNLOOKUP +g = string_fmt_append(g, + " Exim version %s\n", EXIM_VERSION_STR); +#endif +return g; +} + + + +/* These are the lookup_info blocks for this driver */ +static lookup_info redis_lookup_info = { + .name = US"redis", /* lookup name */ + .type = lookup_querystyle, /* query-style lookup */ + .open = redis_open, /* open function */ + .check = NULL, /* no check function */ + .find = redis_find, /* find function */ + .close = NULL, /* no close function */ + .tidy = redis_tidy, /* tidy function */ + .quote = redis_quote, /* quoting function */ + .version_report = redis_version_report /* version reporting */ +}; + +#ifdef DYNLOOKUP +# define redis_lookup_module_info _lookup_module_info +#endif /* DYNLOOKUP */ + +static lookup_info *_lookup_list[] = { &redis_lookup_info }; +lookup_module_info redis_lookup_module_info = { LOOKUP_MODULE_INFO_MAGIC, _lookup_list, 1 }; + +#endif /* LOOKUP_REDIS */ +/* End of lookups/redis.c */ |