- Use time_t instead of abstract minutes to store validity time to make sure we support all possible values. - Return UNIX time from it to support both relative and absolute expire times. - Pass a current time to gsm340_validity_period() to compute the absolute expire time if a relative time is specified. What time is "current" is to b - We also introduce SMS_DEFAULT_VALIDITY_PERIOD macros to reduce number of magic values.
PS This is a first patch of a series of patches which fix SMS validity time decoding. I'm cleaning the patch set and want to see if this patch is fine, as other patches rely on it. -- Regards, Alexander Chemeris. CEO, Fairwaves, Inc. / ООО УмРадио https://fairwaves.co
From 840b7ca3efa834a0d02e4e32f62d3dac63c6bac6 Mon Sep 17 00:00:00 2001 From: Alexander Chemeris <[email protected]> Date: Tue, 26 Nov 2013 16:43:10 -0600 Subject: [PATCH] sms: Proper decoding and storage of SMS validity period. - Use time_t instead of abstract minutes to store validity time to make sure we support all possible values. - Return UNIX time from it to support both relative and absolute expire times. - Pass a current time to gsm340_validity_period() to compute the absolute expire time if a relative time is specified. What time is "current" is to be decided by callers. - We also introduce SMS_DEFAULT_VALIDITY_PERIOD macros to reduce number of magic values. --- include/osmocom/gsm/gsm0411_utils.h | 7 ++-- src/gsm/gsm0411_utils.c | 62 +++++++++++++++-------------------- 2 files changed, 31 insertions(+), 38 deletions(-) diff --git a/include/osmocom/gsm/gsm0411_utils.h b/include/osmocom/gsm/gsm0411_utils.h index ad368e6..cad3625 100644 --- a/include/osmocom/gsm/gsm0411_utils.h +++ b/include/osmocom/gsm/gsm0411_utils.h @@ -3,6 +3,9 @@ #include <time.h> +/* Default SMS validity period is 2 days */ +#define SMS_DEFAULT_VALIDITY_PERIOD (2 * 24 * 60 * 60) + /* Turn int into semi-octet representation: 98 => 0x89 */ uint8_t gsm411_bcdify(uint8_t value); @@ -17,8 +20,8 @@ void gsm340_gen_scts(uint8_t *scts, time_t time); /* Decode 03.40 TP-SCTS (into utc/gmt timestamp) */ time_t gsm340_scts(uint8_t *scts); -/* decode validity period. return minutes */ -unsigned long gsm340_validity_period(uint8_t sms_vpf, uint8_t *sms_vp); +/* decode validity period. return absolute time */ +time_t gsm340_validity_period(time_t now, uint8_t sms_vpf, uint8_t *sms_vp); /* determine coding alphabet dependent on GSM 03.38 Section 4 DCS */ enum sms_alphabet gsm338_get_sms_alphabet(uint8_t dcs); diff --git a/src/gsm/gsm0411_utils.c b/src/gsm/gsm0411_utils.c index a8ba810..1a6862b 100644 --- a/src/gsm/gsm0411_utils.c +++ b/src/gsm/gsm0411_utils.c @@ -34,6 +34,7 @@ #include <osmocom/gsm/gsm48.h> #include <osmocom/gsm/gsm_utils.h> +#include <osmocom/gsm/gsm0411_utils.h> #include <osmocom/gsm/protocol/gsm_03_40.h> #include <osmocom/gsm/protocol/gsm_04_11.h> @@ -121,16 +122,14 @@ time_t gsm340_scts(uint8_t *scts) } /* Return the default validity period in minutes */ -static unsigned long gsm340_vp_default(void) +static time_t gsm340_vp_default(time_t now) { - unsigned long minutes; /* Default validity: two days */ - minutes = 24 * 60 * 2; - return minutes; + return now + SMS_DEFAULT_VALIDITY_PERIOD; } /* Decode validity period format 'relative' */ -static unsigned long gsm340_vp_relative(uint8_t *sms_vp) +static unsigned long gsm340_vp_relative(time_t now, uint8_t *sms_vp) { /* Chapter 9.2.3.12.1 */ uint8_t vp; @@ -145,58 +144,49 @@ static unsigned long gsm340_vp_relative(uint8_t *sms_vp) minutes = vp-166 * 60 * 24; else minutes = vp-192 * 60 * 24 * 7; - return minutes; + + /* Calculate absolute time from the relative offset */ + return now + minutes * 60; } /* Decode validity period format 'absolute' */ -static unsigned long gsm340_vp_absolute(uint8_t *sms_vp) +static time_t gsm340_vp_absolute(uint8_t *sms_vp) { /* Chapter 9.2.3.12.2 */ - time_t expires, now; - unsigned long minutes; - - expires = gsm340_scts(sms_vp); - now = time(NULL); - if (expires <= now) - minutes = 0; - else - minutes = (expires-now)/60; - return minutes; + return gsm340_scts(sms_vp); } /* Decode validity period format 'relative in integer representation' */ -static unsigned long gsm340_vp_relative_integer(uint8_t *sms_vp) +static time_t gsm340_vp_relative_integer(time_t now, uint8_t *sms_vp) { uint8_t vp; - unsigned long minutes; vp = *(sms_vp); if (vp == 0) { LOGP(DLSMS, LOGL_ERROR, "reserved relative_integer validity period\n"); - return gsm340_vp_default(); + return gsm340_vp_default(now); } - minutes = vp/60; - return minutes; + return now + vp; } /* Decode validity period format 'relative in semi-octet representation' */ -static unsigned long gsm340_vp_relative_semioctet(uint8_t *sms_vp) +static time_t gsm340_vp_relative_semioctet(time_t now, uint8_t *sms_vp) { - unsigned long minutes; - minutes = gsm411_unbcdify(*sms_vp++)*60; /* hours */ - minutes += gsm411_unbcdify(*sms_vp++); /* minutes */ - minutes += gsm411_unbcdify(*sms_vp++)/60; /* seconds */ - return minutes; + unsigned long hours, minutes, seconds; + hours = gsm411_unbcdify(*sms_vp++); /* hours */ + minutes = gsm411_unbcdify(*sms_vp++); /* minutes */ + seconds = gsm411_unbcdify(*sms_vp++); /* seconds */ + return now + hours*60*60 + minutes*60 + seconds; } /* decode validity period. return minutes */ -unsigned long gsm340_validity_period(uint8_t sms_vpf, uint8_t *sms_vp) +time_t gsm340_validity_period(time_t now, uint8_t sms_vpf, uint8_t *sms_vp) { uint8_t fi; /* functionality indicator */ switch (sms_vpf) { case GSM340_TP_VPF_RELATIVE: - return gsm340_vp_relative(sms_vp); + return gsm340_vp_relative(now, sms_vp); case GSM340_TP_VPF_ABSOLUTE: return gsm340_vp_absolute(sms_vp); case GSM340_TP_VPF_ENHANCED: @@ -207,23 +197,23 @@ unsigned long gsm340_validity_period(uint8_t sms_vpf, uint8_t *sms_vp) /* read validity period format */ switch (fi & 0x7) { case 0x0: - return gsm340_vp_default(); /* no vpf specified */ + return gsm340_vp_default(now); /* no vpf specified */ case 0x1: - return gsm340_vp_relative(sms_vp); + return gsm340_vp_relative(now, sms_vp); case 0x2: - return gsm340_vp_relative_integer(sms_vp); + return gsm340_vp_relative_integer(now, sms_vp); case 0x3: - return gsm340_vp_relative_semioctet(sms_vp); + return gsm340_vp_relative_semioctet(now, sms_vp); default: /* The GSM spec says that the SC should reject any unsupported and/or undefined values. FIXME */ LOGP(DLSMS, LOGL_ERROR, "Reserved enhanced validity period format\n"); - return gsm340_vp_default(); + return gsm340_vp_default(now); } case GSM340_TP_VPF_NONE: default: - return gsm340_vp_default(); + return gsm340_vp_default(now); } } -- 1.7.9.5
