From: Pekka Helenius Date: Tue, 04 Aug 2020 01:52:18 +0300 Subject: Add user agent string support for HTTPS constraints, update ChangeLog --- a/src/parse.y 2020-08-03 23:22:43.401482642 +0300 +++ b/src/parse.y 2020-08-04 01:03:44.458183310 +0300 @@ -69,6 +69,7 @@ struct opts { int trusted; char *refstr; int port; + char *useragent; int pos_num; double pos_decimal; } opts; @@ -91,6 +92,7 @@ typedef struct { %token SERVER SERVERS SENSOR CORRECTION RTABLE REFID STRATUM WEIGHT %token ERROR %token PORT +%token USERAGENT %token _NTPD_USER %token _DRIFTFILE @@ -164,6 +166,7 @@ typedef struct { %type weight %type trusted %type port +%type useragent %type pos_num %type pos_decimal @@ -376,6 +379,8 @@ main : LISTEN ON address listen_opts { p->addr_head.pool = ++poolseqnum; p->addr_head.name = strdup($3->name); + if ($4.useragent) + p->useragent = strdup($4.useragent); p->addr_head.path = strdup($3->path); if (p->addr_head.name == NULL || p->addr_head.path == NULL) @@ -425,6 +430,8 @@ main : LISTEN ON address listen_opts { p->addr_head.pool = 0; p->addr_head.name = strdup($3->name); + if ($4.useragent) + p->useragent = strdup($4.useragent); p->addr_head.path = strdup($3->path); if (p->addr_head.name == NULL || p->addr_head.path == NULL) @@ -735,7 +742,7 @@ constraint_opts : { opts_default(); } constraint_opts_l : constraint_opts_l constraint_opt | constraint_opt ; -constraint_opt : port +constraint_opt : port | useragent ; sensor_opts : { opts_default(); } @@ -803,6 +810,19 @@ port : PORT NUMBER { } ; +useragent : USERAGENT STRING { + size_t l = strlen($2); + + if (l < 1 || l > USERAGENT_MAX_LENGTH) { + yyerror("user agent string length must be from 1 to %d characters", + USERAGENT_MAX_LENGTH); + free($2); + YYERROR; + } + opts.useragent = $2; + } + ; + rtable : RTABLE NUMBER { #ifdef RT_TABLEID_MAX if ($2 < 0 || $2 > RT_TABLEID_MAX) { @@ -924,6 +944,7 @@ lookup(char *s) { "trustlevel_badpeer", _TRUSTLEVEL_BADPEER, "single" }, { "trustlevel_max", _TRUSTLEVEL_MAX, "single" }, { "trustlevel_pathetic", _TRUSTLEVEL_PATHETIC, "single" }, + { "useragent", USERAGENT, "multiple" }, { "weight", WEIGHT, "multiple" }, }; struct keywords *p; --- a/src/ntpd.h 2020-08-03 23:25:02.978705101 +0300 +++ b/src/ntpd.h 2020-08-03 23:41:03.644863921 +0300 @@ -114,6 +114,8 @@ #define CONSTRAINT_CA SYSCONFDIR "/ssl/cert.pem" #define CONSTRAINT_CA_VALIDATION 0x01; +#define USERAGENT_MAX_LENGTH 256 + #define PARENT_SOCK_FILENO CONSTRAINT_PASSFD #define NTP_PROC_NAME "ntp_main" @@ -159,9 +161,11 @@ struct ntp_addr_wrap { struct ntp_addr_msg { struct ntp_addr a; int port; - size_t namelen; - size_t pathlen; + char useragent[USERAGENT_MAX_LENGTH]; + size_t namelen; + size_t pathlen; size_t portlen; + size_t agentlen; }; struct ntp_status { @@ -239,6 +243,7 @@ struct constraint { time_t last; time_t constraint; int dnstries; + char *useragent; }; struct ntp_conf_sensor { @@ -495,6 +500,7 @@ struct httpsdate { char *tls_hostname; char *tls_path; char *tls_request; + char *tls_useragent; struct tls_config *tls_config; struct tls *tls_ctx; struct tm tls_tm; @@ -502,11 +508,11 @@ struct httpsdate { struct httpsdate * httpsdate_init(const char *, const int *, const char *, - const char *, const u_int8_t *, size_t); + const char *, const char *, const u_int8_t *, size_t); void httpsdate_free(void *); int httpsdate_request(struct httpsdate *, struct timeval *); void *httpsdate_query(const char *, const int *, const char *, - const char *, const u_int8_t *, size_t, + const char *, const char *, const u_int8_t *, size_t, struct timeval *, struct timeval *); char *tls_readline(struct tls *, size_t *, size_t *, struct timeval *); --- a/src/constraint.c 2020-08-02 01:58:28.366952848 +0300 +++ b/src/constraint.c 2020-08-03 23:43:48.584926017 +0300 @@ -132,7 +132,7 @@ constraint_query(struct constraint *cstr { time_t now; struct ntp_addr_msg am; - struct iovec iov[4]; + struct iovec iov[5]; int iov_cnt = 0; now = getmonotime(); @@ -185,6 +185,18 @@ constraint_query(struct constraint *cstr memcpy(&am.a, cstr->addr, sizeof(am.a)); memcpy(&am.port, &cstr->addr_head.port, sizeof(am.port)); + if (cstr->useragent) + memcpy(&am.useragent, cstr->useragent, USERAGENT_MAX_LENGTH); +/* + * FIXME For some reason, dynamically allocating user agent string size does not seem to work + * Investigate, why usage of dynamic memory allocated data fails. + * + if (cstr->useragent) { + if ((am.useragent = calloc(1, strlen(cstr->useragent)) ) == NULL) + fatal("constraint id %d: can't allocate memory for user agent string", cstr->id); + memcpy(am.useragent, cstr->useragent, strlen(cstr->useragent)); + } +*/ iov[iov_cnt].iov_base = &am; iov[iov_cnt++].iov_len = sizeof(am); if (cstr->addr_head.name) { @@ -202,6 +214,11 @@ constraint_query(struct constraint *cstr iov[iov_cnt].iov_base = &cstr->addr_head.port; iov[iov_cnt++].iov_len = am.portlen; } + if (cstr->useragent) { + am.agentlen = strlen(cstr->useragent) + 1; + iov[iov_cnt].iov_base = cstr->useragent; + iov[iov_cnt++].iov_len = am.agentlen; + } imsg_composev(ibuf_main, IMSG_CONSTRAINT_QUERY, cstr->id, 0, -1, iov, iov_cnt); @@ -228,8 +245,9 @@ priv_constraint_msg(u_int32_t id, u_int8 log_warnx("constraint id %d: longer query expected", id); return; } + memcpy(&am, data, sizeof(am)); - if (len != (sizeof(am) + am.namelen + am.pathlen + am.portlen)) { + if (len != (sizeof(am) + am.namelen + am.pathlen + am.portlen + am.agentlen)) { log_warnx("constraint id %d: invalid query received", id); return; } @@ -238,6 +256,7 @@ priv_constraint_msg(u_int32_t id, u_int8 if ((h = calloc(1, sizeof(*h))) == NULL) fatal("constraint id %d: can't allocate memory for network address", id); memcpy(h, &am.a, sizeof(*h)); + h->next = NULL; cstr = new_constraint(); @@ -308,7 +327,7 @@ priv_constraint_readquery(struct constra ); memcpy(am, imsg.data, sizeof(*am)); - if (mlen != (sizeof(*am) + am->namelen + am->pathlen + am->portlen)) + if (mlen != (sizeof(*am) + am->namelen + am->pathlen + am->portlen + am->agentlen)) fatalx("constraint: invalid message length received from parent process (%s)", __func__ ); @@ -327,6 +346,8 @@ priv_constraint_readquery(struct constra cstr->port = port; cstr->addr_head.port = port; + cstr->useragent = strdup(am->useragent); + dptr = imsg.data; memcpy(*data, dptr + sizeof(*am), mlen - sizeof(*am)); imsg_free(&imsg); @@ -464,7 +485,7 @@ priv_constraint_child(const char *pw_dir log_debug("constraint %s: initializing HTTPS request", addr); if ((ctx = httpsdate_query(addr, &cstr.addr_head.port, cstr.addr_head.name, cstr.addr_head.path, - conf->ca, conf->ca_len, &rectv, &xmttv)) == NULL) { + cstr.useragent, conf->ca, conf->ca_len, &rectv, &xmttv)) == NULL) { log_debug("constraint %s: failed to get proper time results", addr); /* Abort with failure but without warning */ exit(1); @@ -852,6 +873,9 @@ constraint_msg_dns(u_int32_t id, u_int8_ ncstr->addr_head.name = strdup(cstr->addr_head.name); ncstr->addr_head.path = strdup(cstr->addr_head.path); ncstr->addr_head.port = intdup(cstr->addr_head.port); + + if (cstr->useragent) + ncstr->useragent = strdup(cstr->useragent); // Unless we do this, we have value 0 in ncstr->port ncstr->port = intdup(cstr->port); --- a/src/constraint-libressl.c 2020-08-01 19:50:24.130263065 +0300 +++ b/src/constraint-libressl.c 2020-08-04 00:01:30.008179382 +0300 @@ -26,7 +26,7 @@ struct httpsdate * httpsdate_init(const char *addr, const int *port, const char *hostname, - const char *path, const u_int8_t *ca, size_t ca_len) + const char *path, const char *useragent, const u_int8_t *ca, size_t ca_len) { struct httpsdate *httpsdate = NULL; char port_s[sizeof(port)]; @@ -45,10 +45,23 @@ httpsdate_init(const char *addr, const i (httpsdate->tls_path = strdup(path)) == NULL) goto fail; - if (asprintf(&httpsdate->tls_request, - "HEAD %s HTTP/1.1\r\nHost: %s\r\nConnection: close\r\n\r\n", - httpsdate->tls_path, httpsdate->tls_hostname) == -1) - goto fail; + if (useragent) + httpsdate->tls_useragent = strdup(useragent); + + if (httpsdate->tls_useragent) { + if (asprintf(&httpsdate->tls_request, + "HEAD %s HTTP/1.1\r\nHost: %s\r\nUser-Agent: %s\r\nConnection: close\r\n\r\n", + httpsdate->tls_path, + httpsdate->tls_hostname, + httpsdate->tls_useragent) == -1) + goto fail; + } else { + if (asprintf(&httpsdate->tls_request, + "HEAD %s HTTP/1.1\r\nHost: %s\r\nConnection: close\r\n\r\n", + httpsdate->tls_path, + httpsdate->tls_hostname) == -1) + goto fail; + } if ((httpsdate->tls_config = tls_config_new()) == NULL) goto fail; @@ -110,6 +123,10 @@ httpsdate_request(struct httpsdate *http if (tls_configure(httpsdate->tls_ctx, httpsdate->tls_config) == -1) goto fail; + if (httpsdate->tls_useragent) + log_debug("constraint %s: user agent: %s", httpsdate->tls_addr, + httpsdate->tls_useragent); + /* * LibreSSL expects an address string, which can also be a DNS name, * but we pass a pre-resolved IP address string in tls_addr so it @@ -222,14 +239,14 @@ httpsdate_request(struct httpsdate *http void * httpsdate_query(const char *addr, const int *port, const char *hostname, - const char *path, const u_int8_t *ca, size_t ca_len, + const char *path, const char *useragent, const u_int8_t *ca, size_t ca_len, struct timeval *rectv, struct timeval *xmttv) { struct httpsdate *httpsdate; struct timeval when; time_t t; - if ((httpsdate = httpsdate_init(addr, port, hostname, path, + if ((httpsdate = httpsdate_init(addr, port, hostname, path, useragent, ca, ca_len)) == NULL) return (NULL); --- a/src/constraint-openssl.c 2020-08-03 19:23:54.377109002 +0300 +++ b/src/constraint-openssl.c 2020-08-04 00:01:16.178179367 +0300 @@ -37,11 +37,20 @@ o_httpsdate_init(struct constraint *cstr if ((httpsdate->cstr = cstr) == NULL) goto fail; - if (asprintf(&httpsdate->tls_request, - "HEAD %s HTTP/1.1\r\nHost: %s\r\nConnection: close\r\n\r\n", - httpsdate->cstr->addr_head.path, - httpsdate->cstr->addr_head.name) == -1) - goto fail; + if (httpsdate->cstr->useragent) { + if (asprintf(&httpsdate->tls_request, + "HEAD %s HTTP/1.1\r\nHost: %s\r\nUser-Agent: %s\r\nConnection: close\r\n\r\n", + httpsdate->cstr->addr_head.path, + httpsdate->cstr->addr_head.name, + httpsdate->cstr->useragent) == -1) + goto fail; + } else { + if (asprintf(&httpsdate->tls_request, + "HEAD %s HTTP/1.1\r\nHost: %s\r\nConnection: close\r\n\r\n", + httpsdate->cstr->addr_head.path, + httpsdate->cstr->addr_head.name) == -1) + goto fail; + } if ((httpsdate->tls_method = TLS_method()) == NULL) goto fail; @@ -161,6 +170,10 @@ o_httpsdate_request(struct o_httpsdate * goto fail; } + if (httpsdate->cstr->useragent) + log_debug("constraint %s: user agent: %s", ia_str, + httpsdate->cstr->useragent); + log_debug("constraint %s: establishing connection", ia_str); ret = SSL_connect(httpsdate->tls_conn); if (ret < 1) { --- a/src/ntpd.conf.5 2020-08-03 23:21:11.124672226 +0300 +++ b/src/ntpd.conf.5 2020-08-04 01:38:53.878185531 +0300 @@ -14,7 +14,7 @@ .\" AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT .\" OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. .\" -.Dd $Mdocdate: August 01 2020 $ +.Dd $Mdocdate: August 04 2020 $ .Dt NTPD.CONF 5 .Os .Sh NAME @@ -58,14 +58,12 @@ is given as an address, .Xr ntpd 8 will listen on all local addresses using the specified routing table. .Xr ntpd 8 -does not listen on any address by default. -The optional +does not listen on any address by default. The optional .Ic rtable keyword will specify which routing table to listen on, if the operating system supports rdomains. By default .Xr ntpd 8 -will listen using the current routing table. -The optional +will listen using the current routing table. The optional .Ic port keyword will specify which local UDP port the NTP server process should use for inbound connections. By default @@ -240,18 +238,29 @@ Configuring a constraint without proper .Xr ntpd 8 to log a warning message on startup. .Bl -tag -width Ds -.It Ic constraint from Ar url [ip...] +.It Xo Ic constraint from Ar url +.Op Ar ip... .Op Ic port Ar port-number +.Op Ic useragent Ar agent-string +.Xc Specify the URL, IP address or the hostname of an HTTPS server to provide a constraint. The optional .Ic port number is an HTTPS server port to connect to. By default .Xr ntpd 8 -will connect to remote TCP port 443. -If the url is followed by one or more addresses the url and addresses will be +will connect to remote TCP port 443. The optional +.Ic useragent +string adds a defined user agent string into a constraint HTTP +request. This option helps retrieving a time constraint from HTTPS +servers which block user agentless HTTP +requests. If the +.Ic url +is followed by one or more +.Ic ip +addresses the URL and addresses will be tried until a working one is found. -The url path and expected certificate name is always taken from the -url specified. +The URL path and expected certificate name is always taken from the +URL specified. If .Ic constraint from is used more than once, @@ -259,29 +268,34 @@ is used more than once, will calculate a median constraint from all the servers specified. .Bd -literal -offset indent server ntp.example.org -constraint from www.example.com +constraint from "www.example.com" constraint from "https://9.9.9.9" "2620:fe::9" -constraint from www.google.com port 443 +constraint from "www.google.com" port 443 useragent "OpenNTPD time query" .Ed -.It Ic constraints from Ar url +.It Xo Ic constraints from Ar url .Op Ic port Ar port-number +.Op Ic useragent Ar agent-string +.Xc As with .Ic constraint from , specify the URL, IP address or the hostname of an HTTPS server to provide a constraint. Should the hostname resolve to multiple IP addresses, .Xr ntpd 8 -will calculate a median constraint from all of them. -The optional +will calculate a median constraint from all of them. The optional .Ic port number is an HTTPS server port to connect to. By default .Xr ntpd 8 -will connect to remote TCP port 443. +will connect to remote TCP port 443. The optional +.Ic useragent +string adds a defined user agent string into a constraint HTTP +request. This option helps retrieving a time constraint from HTTPS +servers which block user agentless HTTP requests. For example: .Bd -literal -offset indent servers pool.ntp.org constraints from "https://www.google.com/" -constraints from "https://duckduckgo.com/" port 443 +constraints from "https://duckduckgo.com/" port 443 useragent "OpenNTPD time query" .Ed .El .Sh ADVANCED KEYWORDS @@ -676,6 +690,16 @@ Negligible drift time to not log in mill 32 .El .Ed +.It Ic max_display_width Ar number +Maximum number of characters in a +.Xr ntpctl 8 +report line (peers, status, sensors and all). +.Bd -literal -offset indent +.Bl -tag -width "Default:" -compact +.It Default: +80 +.El +.Ed .It Ic max_frequency_adjust Ar decimal Maximum allowed frequency correction per iteration. .Bd -literal -offset indent @@ -780,6 +804,14 @@ Sensor default reference ID string. "HARD" .El .Ed +.It Ic sensor_offsets Ar seconds +Maximum allowed sensor time offset in seconds. +.Bd -literal -offset indent +.Bl -tag -width "Default:" -compact +.It Default: +6 +.El +.Ed .It Ic sensor_query_interval Ar seconds Sensor query interval in seconds. .Bd -literal -offset indent --- a/ChangeLog 2020-08-02 14:01:47.093664999 +0300 +++ b/ChangeLog 2020-08-04 01:52:06.054853035 +0300 @@ -32,6 +32,10 @@ OpenNTPD Portable Release Notes: * Many previously hardcoded values are now configurable via conf file. + * Implement UDP & TCP port selection for multiple options. + + * Implement custom user agent string support for constraints. + * Implemented OpenSSL support. Either LibreSSL or OpenSSL can be used. * Improved log entries interpretation.