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diff --git a/src/local/command.c b/src/local/command.c
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+/*++
+/* NAME
+/* command 3
+/* SUMMARY
+/* message delivery to shell command
+/* SYNOPSIS
+/* #include "local.h"
+/*
+/* int deliver_command(state, usr_attr, command)
+/* LOCAL_STATE state;
+/* USER_ATTR exp_attr;
+/* const char *command;
+/* DESCRIPTION
+/* deliver_command() runs a command with a message as standard
+/* input. A limited amount of standard output and standard error
+/* output is captured for diagnostics purposes.
+/* Duplicate commands for the same recipient are suppressed.
+/* A limited amount of information is exported via the environment:
+/* HOME, SHELL, LOGNAME, USER, EXTENSION, DOMAIN, RECIPIENT (entire
+/* address) LOCAL (just the local part) and SENDER. The exported
+/* information is censored with var_cmd_filter.
+/*
+/* Arguments:
+/* .IP state
+/* The attributes that specify the message, recipient and more.
+/* Attributes describing the alias, include or forward expansion.
+/* A table with the results from expanding aliases or lists.
+/* .IP usr_attr
+/* Attributes describing user rights and environment.
+/* .IP command
+/* The shell command to be executed. If possible, the command is
+/* executed without actually invoking a shell. if the command is
+/* the mailbox_command, it is subjected to $name expansion.
+/* DIAGNOSTICS
+/* deliver_command() returns non-zero when delivery should be
+/* tried again,
+/* SEE ALSO
+/* mailbox(3) deliver to mailbox
+/* LICENSE
+/* .ad
+/* .fi
+/* The Secure Mailer license must be distributed with this software.
+/* AUTHOR(S)
+/* Wietse Venema
+/* IBM T.J. Watson Research
+/* P.O. Box 704
+/* Yorktown Heights, NY 10598, USA
+/*--*/
+
+/* System library. */
+
+#include <sys_defs.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <stdarg.h>
+#include <string.h>
+
+/* Utility library. */
+
+#include <msg.h>
+#include <htable.h>
+#include <vstring.h>
+#include <vstream.h>
+#include <argv.h>
+#include <mac_parse.h>
+
+/* Global library. */
+
+#include <defer.h>
+#include <bounce.h>
+#include <sent.h>
+#include <been_here.h>
+#include <mail_params.h>
+#include <pipe_command.h>
+#include <mail_copy.h>
+#include <dsn_util.h>
+#include <mail_parm_split.h>
+
+/* Application-specific. */
+
+#include "local.h"
+
+/* deliver_command - deliver to shell command */
+
+int deliver_command(LOCAL_STATE state, USER_ATTR usr_attr, const char *command)
+{
+ const char *myname = "deliver_command";
+ DSN_BUF *why = state.msg_attr.why;
+ int cmd_status;
+ int deliver_status;
+ ARGV *env;
+ int copy_flags;
+ char **cpp;
+ char *cp;
+ ARGV *export_env;
+ VSTRING *exec_dir;
+ int expand_status;
+
+ /*
+ * Make verbose logging easier to understand.
+ */
+ state.level++;
+ if (msg_verbose)
+ MSG_LOG_STATE(myname, state);
+
+ /*
+ * DUPLICATE ELIMINATION
+ *
+ * Skip this command if it was already delivered to as this user.
+ */
+ if (been_here(state.dup_filter, "command %s:%ld %s",
+ state.msg_attr.user, (long) usr_attr.uid, command))
+ return (0);
+
+ /*
+ * Don't deliver a trace-only request.
+ */
+ if (DEL_REQ_TRACE_ONLY(state.request->flags)) {
+ dsb_simple(why, "2.0.0", "delivers to command: %s", command);
+ return (sent(BOUNCE_FLAGS(state.request),
+ SENT_ATTR(state.msg_attr)));
+ }
+
+ /*
+ * DELIVERY RIGHTS
+ *
+ * Choose a default uid and gid when none have been selected (i.e. values
+ * are still zero).
+ */
+ if (usr_attr.uid == 0 && (usr_attr.uid = var_default_uid) == 0)
+ msg_panic("privileged default user id");
+ if (usr_attr.gid == 0 && (usr_attr.gid = var_default_gid) == 0)
+ msg_panic("privileged default group id");
+
+ /*
+ * Deliver.
+ */
+ copy_flags = MAIL_COPY_FROM | MAIL_COPY_RETURN_PATH
+ | MAIL_COPY_ORIG_RCPT;
+ if (local_deliver_hdr_mask & DELIVER_HDR_CMD)
+ copy_flags |= MAIL_COPY_DELIVERED;
+
+ if (vstream_fseek(state.msg_attr.fp, state.msg_attr.offset, SEEK_SET) < 0)
+ msg_fatal("%s: seek queue file %s: %m",
+ myname, VSTREAM_PATH(state.msg_attr.fp));
+
+ /*
+ * Pass additional environment information. XXX This should be
+ * configurable. However, passing untrusted information via environment
+ * parameters opens up a whole can of worms. Lesson from web servers:
+ * don't let any network data even near a shell. It causes trouble.
+ */
+ env = argv_alloc(1);
+ if (usr_attr.home)
+ argv_add(env, "HOME", usr_attr.home, ARGV_END);
+ argv_add(env,
+ "LOGNAME", state.msg_attr.user,
+ "USER", state.msg_attr.user,
+ "SENDER", state.msg_attr.sender,
+ "RECIPIENT", state.msg_attr.rcpt.address,
+ "LOCAL", state.msg_attr.local,
+ ARGV_END);
+ if (usr_attr.shell)
+ argv_add(env, "SHELL", usr_attr.shell, ARGV_END);
+ if (state.msg_attr.domain)
+ argv_add(env, "DOMAIN", state.msg_attr.domain, ARGV_END);
+ if (state.msg_attr.extension)
+ argv_add(env, "EXTENSION", state.msg_attr.extension, ARGV_END);
+ if (state.msg_attr.rcpt.orig_addr && state.msg_attr.rcpt.orig_addr[0])
+ argv_add(env, "ORIGINAL_RECIPIENT", state.msg_attr.rcpt.orig_addr,
+ ARGV_END);
+
+#define EXPORT_REQUEST(name, value) \
+ if ((value)[0]) argv_add(env, (name), (value), ARGV_END);
+
+ EXPORT_REQUEST("CLIENT_HOSTNAME", state.msg_attr.request->client_name);
+ EXPORT_REQUEST("CLIENT_ADDRESS", state.msg_attr.request->client_addr);
+ EXPORT_REQUEST("CLIENT_HELO", state.msg_attr.request->client_helo);
+ EXPORT_REQUEST("CLIENT_PROTOCOL", state.msg_attr.request->client_proto);
+ EXPORT_REQUEST("SASL_METHOD", state.msg_attr.request->sasl_method);
+ EXPORT_REQUEST("SASL_SENDER", state.msg_attr.request->sasl_sender);
+ EXPORT_REQUEST("SASL_USERNAME", state.msg_attr.request->sasl_username);
+
+ argv_terminate(env);
+
+ /*
+ * Censor out undesirable characters from exported data.
+ */
+ for (cpp = env->argv; *cpp; cpp += 2)
+ for (cp = cpp[1]; *(cp += strspn(cp, var_cmd_exp_filter)) != 0;)
+ *cp++ = '_';
+
+ /*
+ * Evaluate the command execution directory. Defer delivery if expansion
+ * fails.
+ */
+ export_env = mail_parm_split(VAR_EXPORT_ENVIRON, var_export_environ);
+ exec_dir = vstring_alloc(10);
+ expand_status = local_expand(exec_dir, var_exec_directory,
+ &state, &usr_attr, var_exec_exp_filter);
+
+ if (expand_status & MAC_PARSE_ERROR) {
+ cmd_status = PIPE_STAT_DEFER;
+ dsb_simple(why, "4.3.5", "mail system configuration error");
+ msg_warn("bad parameter value syntax for %s: %s",
+ VAR_EXEC_DIRECTORY, var_exec_directory);
+ } else {
+ cmd_status = pipe_command(state.msg_attr.fp, why,
+ CA_PIPE_CMD_UID(usr_attr.uid),
+ CA_PIPE_CMD_GID(usr_attr.gid),
+ CA_PIPE_CMD_COMMAND(command),
+ CA_PIPE_CMD_COPY_FLAGS(copy_flags),
+ CA_PIPE_CMD_SENDER(state.msg_attr.sender),
+ CA_PIPE_CMD_ORIG_RCPT(state.msg_attr.rcpt.orig_addr),
+ CA_PIPE_CMD_DELIVERED(state.msg_attr.delivered),
+ CA_PIPE_CMD_TIME_LIMIT(var_command_maxtime),
+ CA_PIPE_CMD_ENV(env->argv),
+ CA_PIPE_CMD_EXPORT(export_env->argv),
+ CA_PIPE_CMD_SHELL(var_local_cmd_shell),
+ CA_PIPE_CMD_CWD(*STR(exec_dir) ?
+ STR(exec_dir) : (char *) 0),
+ CA_PIPE_CMD_END);
+ }
+ vstring_free(exec_dir);
+ argv_free(export_env);
+ argv_free(env);
+
+ /*
+ * Depending on the result, bounce or defer the message.
+ */
+ switch (cmd_status) {
+ case PIPE_STAT_OK:
+ dsb_simple(why, "2.0.0", "delivered to command: %s", command);
+ deliver_status = sent(BOUNCE_FLAGS(state.request),
+ SENT_ATTR(state.msg_attr));
+ break;
+ case PIPE_STAT_BOUNCE:
+ case PIPE_STAT_DEFER:
+ /* Account for possible owner- sender address override. */
+ deliver_status = bounce_workaround(state);
+ break;
+ case PIPE_STAT_CORRUPT:
+ deliver_status = DEL_STAT_DEFER;
+ break;
+ default:
+ msg_panic("%s: bad status %d", myname, cmd_status);
+ /* NOTREACHED */
+ }
+
+ return (deliver_status);
+}
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