Adding upstream version 4.92.upstream/4.92upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

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..a4b672a
--- /dev/null
+++ b/src/lookups/redis.c
@@ -0,0 +1,471 @@
+/*************************************************
+*     Exim - an Internet mail transport agent    *
+*************************************************/
+
+/* 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(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("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
+
+    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)
+{
+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 (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("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 = string_sprintf("REDIS connection failed");
+    *defer_break = FALSE;
+    goto REDIS_EXIT;
+    }
+
+  /* Add the connection to the cache */
+  cn = store_get(sizeof(redis_connection));
+  cn->server = server_copy;
+  cn->handle = redis_handle;
+  cn->next = redis_connections;
+  redis_connections = cn;
+  }
+else
+  {
+  DEBUG(D_lookup)
+    debug_printf("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("REDIS: Selecting database=%s\n", sdata[1]);
+  }
+
+/* split string on whitespace into argv */
+  {
+  uschar * argv[32];
+  int i;
+  const uschar * s = command;
+  int siz, ptr;
+  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("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. */
+
+  redis_reply = redisCommandArgv(redis_handle, i, (const char **) argv, NULL);
+  if (!redis_reply)
+    {
+    *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("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("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 (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 (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("REDIS: result has nesting of arrays which"
+		    " is not supported. Ignoring!\n");
+		break;
+	      default:
+		DEBUG(D_lookup) debug_printf(
+			  "REDIS: result has unsupported type. Ignoring!\n");
+		break;
+	      }
+	    }
+	    break;
+	  default:
+	    DEBUG(D_lookup) debug_printf("REDIS: query returned unsupported type\n");
+	    break;
+	  }
+	}
+      break;
+  }
+
+
+if (result)
+  store_reset(result->s + result->ptr + 1);
+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("%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)),
+  uschar *filename __attribute__((unused)),
+  const uschar *command, int length, uschar **result, uschar **errmsg,
+  uint *do_cache)
+{
+return lf_sqlperform(US"Redis", US"redis_servers", redis_servers, command,
+  result, errmsg, do_cache, 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
+
+Returns:     the processed string or NULL for a bad option
+*/
+
+static uschar *
+redis_quote(uschar *s, uschar *opt)
+{
+register int c;
+int count = 0;
+uschar *t = s;
+uschar *quoted;
+
+if (opt) return NULL;     /* No options recognized */
+
+while ((c = *t++) != 0)
+  if (isspace(c) || c == '\\') count++;
+
+if (count == 0) return s;
+t = quoted = store_get(Ustrlen(s) + count + 1);
+
+while ((c = *s++) != 0)
+  {
+  if (isspace(c) || c == '\\') *t++ = '\\';
+  *t++ = c;
+  }
+
+*t = 0;
+return quoted;
+}
+
+
+/*************************************************
+*         Version reporting entry point          *
+*************************************************/
+#include "../version.h"
+
+void
+redis_version_report(FILE *f)
+{
+fprintf(f, "Library version: REDIS: Compile: %d [%d]\n",
+               HIREDIS_MAJOR, HIREDIS_MINOR);
+#ifdef DYNLOOKUP
+fprintf(f, "                        Exim version %s\n", EXIM_VERSION_STR);
+#endif
+}
+
+
+
+/* These are the lookup_info blocks for this driver */
+static lookup_info redis_lookup_info = {
+  US"redis",                     /* lookup name */
+  lookup_querystyle,             /* query-style lookup */
+  redis_open,                    /* open function */
+  NULL,                          /* no check function */
+  redis_find,                    /* find function */
+  NULL,                          /* no close function */
+  redis_tidy,                    /* tidy function */
+  redis_quote,                   /* quoting function */
+  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 */