[systemd-devel] [PATCH] journald: Introduce RFC 5424 syslog
Susant Sahani
susant at redhat.com
Thu Feb 19 08:18:46 PST 2015
On Thu, 19 Feb 2015 13:53:42 +0530, Umut Tezduyar Lindskog
<umut at tezduyar.com> wrote:
> Hi Susant,
Hi Umut,
Thanks for reviewing.
>
> On Thu, Feb 19, 2015 at 8:58 AM, Susant Sahani <susant at redhat.com> wrote:
>> This patch adds support for RFC 5424 syslog format to journald. Journald
>> can now forward logs to a multicast UDP group.
>>
>> RFC 5424 format:
>> <PRI>VERSION SP TIMESTAMP SP HOSTNAME SP APP-NAME SP PROCID SP MSGID SP
>> [SD-ID]s SP MSG
>>
>> Example conf:
>>
>> file: journald.conf
>> SysLogAddress=239.0.0.1:6000
>> ---
>> Makefile.am | 1 +
>> man/journald.conf.xml | 12 ++
>> src/journal/journald-gperf.gperf | 1 +
>> src/journal/journald-native.c | 3 +
>> src/journal/journald-server.c | 40 +++++-
>> src/journal/journald-server.h | 14 ++
>> src/journal/journald-stream.c | 4 +
>> src/journal/journald-syslog-network.c | 246
>> ++++++++++++++++++++++++++++++++++
>> src/journal/journald-syslog.c | 3 +
>> src/journal/journald-syslog.h | 2 +
>> 10 files changed, 325 insertions(+), 1 deletion(-)
>> create mode 100644 src/journal/journald-syslog-network.c
>>
>> diff --git a/Makefile.am b/Makefile.am
>> index ba63f68..b015f69 100644
>> --- a/Makefile.am
>> +++ b/Makefile.am
>> @@ -4487,6 +4487,7 @@ libsystemd_journal_core_la_SOURCES = \
>> src/journal/journald-kmsg.h \
>> src/journal/journald-syslog.c \
>> src/journal/journald-syslog.h \
>> + src/journal/journald-syslog-network.c \
>> src/journal/journald-stream.c \
>> src/journal/journald-stream.h \
>> src/journal/journald-server.c \
>> diff --git a/man/journald.conf.xml b/man/journald.conf.xml
>> index 364b58f..4fb037b 100644
>> --- a/man/journald.conf.xml
>> +++ b/man/journald.conf.xml
>> @@ -355,6 +355,18 @@
>> </varlistentry>
>>
>> <varlistentry>
>> + <term><varname>SysLogAddress=</varname></term>
>> + <listitem><para>Controls whether log messages received by the
>> + journal daemon shall be forwarded to a multicast UDP network
>> + group in syslog RFC 5424 format.</para>
>> +
>> + <para>The the address string format is similar to socket
>> units. See
> Double "the".
>> +
>> <citerefentry><refentrytitle>systemd.socket</refentrytitle><manvolnum>1</manvolnum></citerefentry>
>> + </para>
>> + </listitem>
>> + </varlistentry>
>> +
>> + <varlistentry>
>> <term><varname>TTYPath=</varname></term>
>>
>> <listitem><para>Change the console TTY to use if
>> diff --git a/src/journal/journald-gperf.gperf
>> b/src/journal/journald-gperf.gperf
>> index 74554c1..9cdffbc 100644
>> --- a/src/journal/journald-gperf.gperf
>> +++ b/src/journal/journald-gperf.gperf
>> @@ -40,3 +40,4 @@ Journal.MaxLevelKMsg, config_parse_log_level,
>> 0, offsetof(Server, max_lev
>> Journal.MaxLevelConsole, config_parse_log_level, 0,
>> offsetof(Server, max_level_console)
>> Journal.MaxLevelWall, config_parse_log_level, 0,
>> offsetof(Server, max_level_wall)
>> Journal.SplitMode, config_parse_split_mode, 0,
>> offsetof(Server, split_mode)
>> +Journal.SysLogAddress, config_parse_syslog_network_address, 0,
>> offsetof(Server, syslog_addr)
>> diff --git a/src/journal/journald-native.c
>> b/src/journal/journald-native.c
>> index 851625d..9fd370f 100644
>> --- a/src/journal/journald-native.c
>> +++ b/src/journal/journald-native.c
>> @@ -273,6 +273,9 @@ void server_process_native_message(
>> if (s->forward_to_syslog)
>> server_forward_syslog(s, priority, identifier,
>> message, ucred, tv);
>>
>> + if (s->forward_to_network)
>> + server_forward_syslog_network(s, priority,
>> identifier, message, ucred, tv);
>> +
>> if (s->forward_to_kmsg)
>> server_forward_kmsg(s, priority, identifier,
>> message, ucred);
>>
>> diff --git a/src/journal/journald-server.c
>> b/src/journal/journald-server.c
>> index 7ee8174..de4ef50 100644
>> --- a/src/journal/journald-server.c
>> +++ b/src/journal/journald-server.c
>> @@ -86,7 +86,7 @@ static const char* const split_mode_table[_SPLIT_MAX]
>> = {
>> DEFINE_STRING_TABLE_LOOKUP(split_mode, SplitMode);
>> DEFINE_CONFIG_PARSE_ENUM(config_parse_split_mode, split_mode,
>> SplitMode, "Failed to parse split mode setting");
>>
>> -static uint64_t available_space(Server *s, bool verbose) {
>> +uint64_t available_space(Server *s, bool verbose) {
>> char ids[33];
>> _cleanup_free_ char *p = NULL;
>> sd_id128_t machine;
>> @@ -1356,6 +1356,35 @@ static int server_parse_config_file(Server *s) {
>> false, s);
>> }
>>
>> +int config_parse_syslog_network_address(const char *unit,
>> + const char *filename,
>> + unsigned line,
>> + const char *section,
>> + unsigned section_line,
>> + const char *lvalue,
>> + int ltype,
>> + const char *rvalue,
>> + void *data,
>> + void *userdata) {
>> + Server *s = userdata;
>> + int r;
>> +
>> + assert(filename);
>> + assert(lvalue);
>> + assert(rvalue);
>> + assert(data);
>> +
>> + r = socket_address_parse(&s->syslog_addr, rvalue);
>> + if (r < 0) {
>> + log_syntax(unit, LOG_ERR, filename, line, -r,
>> + "Failed to parse address value, ignoring:
>> %s", rvalue);
>> + return 0;
>> + }
>> +
>> + s->forward_to_network = true;
>> + return 0;
>> +}
>> +
>> static int server_dispatch_sync(sd_event_source *es, usec_t t, void
>> *userdata) {
>> Server *s = userdata;
>>
>> @@ -1578,6 +1607,10 @@ int server_init(Server *s) {
>> if (r < 0)
>> return r;
>>
>> + r = server_open_syslog_network_socket(s);
> What happens if forwarding is not enabled?
We need to do a check here whether it's enabled ?
>> + if (r < 0)
>> + log_error_errno(r, "Failed to open syslog network
>> socket. Ignoring: %m.");
>> +
>> r = server_open_native_socket(s);
>> if (r < 0)
>> return r;
>> @@ -1673,6 +1706,7 @@ void server_done(Server *s) {
>> sd_event_unref(s->event);
>>
>> safe_close(s->syslog_fd);
>> + safe_close(s->syslog_network_fd);
>> safe_close(s->native_fd);
>> safe_close(s->stdout_fd);
>> safe_close(s->dev_kmsg_fd);
>> @@ -1682,6 +1716,9 @@ void server_done(Server *s) {
>> if (s->rate_limit)
>> journal_rate_limit_free(s->rate_limit);
>>
>> + if (s->syslog_network_rate_limit)
>> + journal_rate_limit_free(s->syslog_network_rate_limit);
>> +
>> if (s->kernel_seqnum)
>> munmap(s->kernel_seqnum, sizeof(uint64_t));
>>
>> @@ -1689,6 +1726,7 @@ void server_done(Server *s) {
>> free(s->tty_path);
>> free(s->cgroup_root);
>> free(s->hostname_field);
>> + free(s->hostname);
>>
>> if (s->mmap)
>> mmap_cache_unref(s->mmap);
>> diff --git a/src/journal/journald-server.h
>> b/src/journal/journald-server.h
>> index c96877c..ba9e456 100644
>> --- a/src/journal/journald-server.h
>> +++ b/src/journal/journald-server.h
>> @@ -27,6 +27,7 @@
>> #include <sys/types.h>
>> #include <sys/socket.h>
>>
>> +#include "socket-util.h"
>> #include "sd-event.h"
>> #include "journal-file.h"
>> #include "hashmap.h"
>> @@ -56,6 +57,7 @@ typedef struct StdoutStream StdoutStream;
>>
>> typedef struct Server {
>> int syslog_fd;
>> + int syslog_network_fd;
>> int native_fd;
>> int stdout_fd;
>> int dev_kmsg_fd;
>> @@ -86,6 +88,8 @@ typedef struct Server {
>> size_t buffer_size;
>>
>> JournalRateLimit *rate_limit;
>> + JournalRateLimit *syslog_network_rate_limit;
>> +
>> usec_t sync_interval_usec;
>> usec_t rate_limit_interval;
>> unsigned rate_limit_burst;
>> @@ -98,12 +102,15 @@ typedef struct Server {
>>
>> bool forward_to_kmsg;
>> bool forward_to_syslog;
>> + bool forward_to_network;
>> bool forward_to_console;
>> bool forward_to_wall;
>>
>> unsigned n_forward_syslog_missed;
>> usec_t last_warn_forward_syslog_missed;
>>
>> + unsigned n_forward_syslog_network_missed;
>> +
>> uint64_t cached_available_space;
>> usec_t cached_available_space_timestamp;
>>
>> @@ -140,6 +147,9 @@ typedef struct Server {
>> char machine_id_field[sizeof("_MACHINE_ID=") + 32];
>> char boot_id_field[sizeof("_BOOT_ID=") + 32];
>> char *hostname_field;
>> + char *hostname;
>> +
>> + SocketAddress syslog_addr;
>>
>> /* Cached cgroup root, so that we don't have to query that all
>> the time */
>> char *cgroup_root;
>> @@ -166,13 +176,17 @@ int config_parse_split_mode(const char *unit,
>> const char *filename, unsigned lin
>> const char *split_mode_to_string(SplitMode s) _const_;
>> SplitMode split_mode_from_string(const char *s) _pure_;
>>
>> +int config_parse_syslog_network_address(const char *unit, const char
>> *filename, unsigned line, const char *section, unsigned section_line,
>> const char *lvalue, int ltype, const char *rvalue,void *data, void
>> *userdata);
>> +
>> void server_fix_perms(Server *s, JournalFile *f, uid_t uid);
>> int server_init(Server *s);
>> void server_done(Server *s);
>> void server_sync(Server *s);
>> void server_vacuum(Server *s);
>> void server_rotate(Server *s);
>> +uint64_t available_space(Server *s, bool verbose);
>> int server_schedule_sync(Server *s, int priority);
>> int server_flush_to_var(Server *s);
>> void server_maybe_append_tags(Server *s);
>> int server_process_datagram(sd_event_source *es, int fd, uint32_t
>> revents, void *userdata);
>> +int server_open_syslog_network_socket(Server *s);
>> diff --git a/src/journal/journald-stream.c
>> b/src/journal/journald-stream.c
>> index 942a857..ccc10a3 100644
>> --- a/src/journal/journald-stream.c
>> +++ b/src/journal/journald-stream.c
>> @@ -69,6 +69,7 @@ struct StdoutStream {
>> int priority;
>> bool level_prefix:1;
>> bool forward_to_syslog:1;
>> + bool forward_to_network:1;
>> bool forward_to_kmsg:1;
>> bool forward_to_console:1;
>>
>> @@ -243,6 +244,9 @@ static int stdout_stream_log(StdoutStream *s, const
>> char *p) {
>> if (s->forward_to_syslog || s->server->forward_to_syslog)
>> server_forward_syslog(s->server,
>> syslog_fixup_facility(priority), s->identifier, p, &s->ucred, NULL);
>>
>> + if (s->forward_to_network || s->server->forward_to_network)
>> + server_forward_syslog_network(s->server,
>> syslog_fixup_facility(priority), s->identifier, p, &s->ucred, NULL);
>> +
>> if (s->forward_to_kmsg || s->server->forward_to_kmsg)
>> server_forward_kmsg(s->server, priority,
>> s->identifier, p, &s->ucred);
>>
>> diff --git a/src/journal/journald-syslog-network.c
>> b/src/journal/journald-syslog-network.c
>> new file mode 100644
>> index 0000000..0f7b494
>> --- /dev/null
>> +++ b/src/journal/journald-syslog-network.c
>> @@ -0,0 +1,246 @@
>> +/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
>> +
>> +/***
>> + This file is part of systemd.
>> +
>> + Copyright 2015 Susant Sahani
>> +
>> + systemd is free software; you can redistribute it and/or modify it
>> + under the terms of the GNU Lesser General Public License as
>> published by
>> + the Free Software Foundation; either version 2.1 of the License, or
>> + (at your option) any later version.
>> +
>> + systemd is distributed in the hope that it will be useful, but
>> + WITHOUT ANY WARRANTY; without even the implied warranty of
>> + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
>> + Lesser General Public License for more details.
>> +
>> + You should have received a copy of the GNU Lesser General Public
>> License
>> + along with systemd; If not, see <http://www.gnu.org/licenses/>.
>> +***/
>> +
>> +#include <unistd.h>
>> +#include <stddef.h>
>> +#include <poll.h>
>> +
>> +#include "shared/in-addr-util.h"
>> +#include "journald-server.h"
>> +#include "journald-syslog.h"
>> +#include "systemd/sd-messages.h"
>> +
>> +/* Warn once every 30s if we missed syslog message */
>> +#define WARN_FORWARD_SYSLOG_MISSED_ID "syslog-network-missed"
>> +
>> +#define RFC_5424_NILVALUE "-"
>> +#define RFC_5424_PROTOCOL 1
>> +
>> +static void server_maybe_warn_forward_syslog_network_missed(Server *s,
>> int priority) {
>> + int r;
>> +
>> + assert(s);
>> +
>> + if (s->n_forward_syslog_network_missed <= 0)
>> + return;
>> +
>> + r = journal_rate_limit_test(s->syslog_network_rate_limit,
>> WARN_FORWARD_SYSLOG_MISSED_ID,
>> + priority & LOG_PRIMASK,
>> available_space(s, false));
>> + if (r == 0)
>> + return;
>> +
>> + server_driver_message(s, SD_MESSAGE_FORWARD_SYSLOG_MISSED,
>> + "Forwarding to syslog network missed %u
>> messages.",
>> + s->n_forward_syslog_network_missed);
>> +
>> + s->n_forward_syslog_network_missed = 0;
>> +}
>> +
>> +static int syslog_network_send(Server *s, struct iovec *iovec,
>> unsigned n_iovec, int priority) {
>> + struct msghdr mh = { };
>> +
>> + assert(s);
>> + assert(iovec);
>> + assert(n_iovec > 0);
>> +
>> + mh.msg_iov = iovec;
>> + mh.msg_iovlen = n_iovec;
>> +
>> + if (s->syslog_addr.sockaddr.sa.sa_family == AF_INET) {
>> + mh.msg_name = &s->syslog_addr.sockaddr.sa;
>> + mh.msg_namelen = sizeof(s->syslog_addr.sockaddr.sa);
>> + } else if (s->syslog_addr.sockaddr.sa.sa_family == AF_INET6) {
>> + mh.msg_name = &s->syslog_addr.sockaddr.in6;
>> + mh.msg_namelen = sizeof(s->syslog_addr.sockaddr.in6);
>> + } else
>> + return -EAFNOSUPPORT;
>> +
>> + if (sendmsg(s->syslog_network_fd, &mh, MSG_NOSIGNAL) >= 0)
>> + return 0;
>> +
>> + s->n_forward_syslog_network_missed++;
> When can forwarding fail that we are keeping track of it? In the end
> we just broadcast messages on UDP.
Does not look like . It's writing to native only.
>> +
>> + server_maybe_warn_forward_syslog_network_missed(s, priority);
>> +
>> + return 0;
>> +}
>> +
>> +/* RFC3339 timestamp format: YYYY-MM-DDTHH:MM:SS[.frac]<+/->ZZ:ZZ */
>> +void format_rfc3339_timestamp(const struct timeval *tv, char
>> *header_time, size_t header_size) {
>> + char gm_buf[sizeof("+0530") + 1];
>> + struct tm tm;
>> + time_t t;
>> +
>> + t = tv ? tv->tv_sec : ((time_t) (now(CLOCK_REALTIME) /
>> USEC_PER_SEC));
>> + localtime_r(&t, &tm);
>> +
>> + strftime(header_time, header_size, "%Y-%m-%dT%T", &tm);
>> +
>> + /* add fractional part */
>> + if (tv)
>> + snprintf(header_time + strlen(header_time),
>> header_size, ".%06ld", tv->tv_usec);
>> +
>> + /* format the timezone according to RFC */
>> + xstrftime(gm_buf, "%z", &tm);
>> + snprintf(header_time + strlen(header_time), header_size,
>> "%.3s:%.2s ", gm_buf, gm_buf + 3);
>> +}
>> +
>> +/* The Syslog Protocol RFC5424 format :
>> + * <PRI>VERSION SP TIMESTAMP SP HOSTNAME SP APP-NAME SP PROCID SP
>> MSGID SP [SD-ID]s SP MSG
>> + */
>> +void server_forward_syslog_network(Server *s,
>> + int priority,
>> + const char *identifier,
>> + const char *message,
>> + const struct ucred *ucred,
>> + const struct timeval *tv) {
>> + char header_pid[DECIMAL_STR_MAX(pid_t) + 1];
>> + char header_priority[sizeof("< >1 ") + 1];
>> + char header_time[FORMAT_TIMESTAMP_MAX];
>> + struct iovec iov[13];
>> + int n = 0;
>> +
>> + assert(s);
>> + assert(priority >= 0);
>> + assert(priority <= 999);
>> + assert(message);
>> +
>> + if (LOG_PRI(priority) > s->max_level_syslog)
>> + return;
>> +
>> + /* First: priority field Second: Version '<pri>version' */
>> + snprintf(header_priority, sizeof(header_priority), "<%i>%i ",
>> priority, RFC_5424_PROTOCOL);
>> + IOVEC_SET_STRING(iov[n++], header_priority);
>> +
>> + /* Third: timestamp */
>> + format_rfc3339_timestamp(tv, header_time, sizeof(header_time));
>> + IOVEC_SET_STRING(iov[n++], header_time);
>> +
>> + /* Fourth: hostname */
>> + if (s->hostname) {
>> + IOVEC_SET_STRING(iov[n++], s->hostname);
>> + IOVEC_SET_STRING(iov[n++], " ");
>> + }
>> +
>> + /* Fifth: app-name or tag */
>> + if (identifier) {
>> + IOVEC_SET_STRING(iov[n++], identifier);
>> + IOVEC_SET_STRING(iov[n++], " ");
>> + } else {
>> + IOVEC_SET_STRING(iov[n++], RFC_5424_NILVALUE);
>> + IOVEC_SET_STRING(iov[n++], " ");
>> + }
>> +
>> + /* Sixth: procid */
>> + if (ucred) {
>> + xsprintf(header_pid, PID_FMT , ucred->pid);
>> +
>> + IOVEC_SET_STRING(iov[n++], header_pid);
>> + IOVEC_SET_STRING(iov[n++], " ");
>> + } else {
>> + IOVEC_SET_STRING(iov[n++], RFC_5424_NILVALUE);
>> + IOVEC_SET_STRING(iov[n++], " ");
>> + }
>> +
>> + /* Seventh: msgid */
>> + IOVEC_SET_STRING(iov[n++], RFC_5424_NILVALUE);
>> + IOVEC_SET_STRING(iov[n++], " ");
>> +
>> + /* Eighth: [structured-data] */
>> + IOVEC_SET_STRING(iov[n++], RFC_5424_NILVALUE);
>> + IOVEC_SET_STRING(iov[n++], " ");
>> +
>> + /* Ninth: message */
>> + IOVEC_SET_STRING(iov[n++], message);
>> +
>> + syslog_network_send(s, iov, n, priority);
>> +}
>> +
>> +static int syslog_network_fd(Server *s) {
>> + const int ttl = 255;
>> + const int one = 1;
>> + int fd, r;
>> +
>> + assert(s);
>> +
>> + fd = socket(s->syslog_addr.sockaddr.sa.sa_family,
>> SOCK_DGRAM|SOCK_CLOEXEC|SOCK_NONBLOCK, 0);
>> + if (fd < 0)
>> + return -errno;
>> +
>> + r = setsockopt(fd, IPPROTO_IP, IP_PKTINFO, &one, sizeof(one));
>> + if (r < 0) {
>> + r = -errno;
>> + goto fail;
>> + }
>> +
>> + r = setsockopt(fd, IPPROTO_IP, IP_MULTICAST_TTL, &ttl,
>> sizeof(ttl));
>> + if (r < 0) {
>> + r = -errno;
>> + goto fail;
>> + }
>> +
>> + r = setsockopt(fd, IPPROTO_IP, IP_MULTICAST_LOOP, &one,
>> sizeof(one));
>> + if (r < 0) {
>> + r = -errno;
>> + goto fail;
>> + }
>> +
>> + s->syslog_network_fd = fd;
>> +
>> + return fd;
>> +
>> + fail:
>> + fd = safe_close(fd);
>> + return r;
>> +}
>> +
>> +int server_open_syslog_network_socket(Server *s) {
>> + int r;
>> +
>> + assert(s);
>> +
>> + s->hostname = gethostname_malloc();
> Do you cover the case where hostname changes after we open the socket?
I guess this should be a separate patch handling such case. Not sure we
are already doing in journal.
>> + if (!s->hostname) {
>> + r = -ENOMEM;
>> + goto fail;
>> + }
>> +
>> + if (s->syslog_addr.sockaddr.sa.sa_family == AF_INET ||
>> s->syslog_addr.sockaddr.sa.sa_family == AF_INET6) {
>> +
>> + r = syslog_network_fd(s);
> Don't you want to embed syslog_network_fd in to this function? If you
> don't, I think the name is a bit confusing as we also have
> s->syslog_network_fd.
I guess u mean s->syslog_network_fd = fd . that's already done .
yes function name can be changed.
it's already done in syslog_network_fd
>> + if (r < 0)
>> + goto fail;
>> + } else {
>> + r = -EAFNOSUPPORT;
>> + goto fail;
>> + }
>> +
>> + s->syslog_network_rate_limit =
>> journal_rate_limit_new(s->rate_limit_interval, s->rate_limit_burst);
>> + if (!s->syslog_network_rate_limit) {
>> + r = -ENOMEM;
>> + goto fail;
>> + }
>> +
>> + return r;
>> + fail:
>> + s->forward_to_network = false;
>> + return r;
>> +}
>> diff --git a/src/journal/journald-syslog.c
>> b/src/journal/journald-syslog.c
>> index 7d545ca..4ecbc43 100644
>> --- a/src/journal/journald-syslog.c
>> +++ b/src/journal/journald-syslog.c
>> @@ -336,6 +336,9 @@ void server_process_syslog_message(
>> syslog_skip_date((char**) &buf);
>> syslog_parse_identifier(&buf, &identifier, &pid);
>>
>> + if (s->forward_to_network)
>> + server_forward_syslog_network(s, priority, identifier,
>> buf, ucred, tv);
>> +
>> if (s->forward_to_kmsg)
>> server_forward_kmsg(s, priority, identifier, buf,
>> ucred);
>>
>> diff --git a/src/journal/journald-syslog.h
>> b/src/journal/journald-syslog.h
>> index 3774ebd..b239825 100644
>> --- a/src/journal/journald-syslog.h
>> +++ b/src/journal/journald-syslog.h
>> @@ -26,8 +26,10 @@
>> int syslog_fixup_facility(int priority) _const_;
>>
>> size_t syslog_parse_identifier(const char **buf, char **identifier,
>> char **pid);
>> +void format_rfc3339_timestamp(const struct timeval *tv, char
>> *header_time, size_t header_size);
>>
>> void server_forward_syslog(Server *s, int priority, const char
>> *identifier, const char *message, const struct ucred *ucred, const
>> struct timeval *tv);
>> +void server_forward_syslog_network(Server *s, int priority, const char
>> *identifier, const char *message, const struct ucred *ucred, const
>> struct timeval *tv);
>>
>> void server_process_syslog_message(Server *s, const char *buf, const
>> struct ucred *ucred, const struct timeval *tv, const char *label,
>> size_t label_len);
>> int server_open_syslog_socket(Server *s);
>> --
>> 2.1.0
>>
Susant
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