<p>Harald Welte <strong>merged</strong> this change.</p><p><a href="https://gerrit.osmocom.org/9529">View Change</a></p><div style="white-space:pre-wrap">Approvals:
Jenkins Builder: Verified
Harald Welte: Looks good to me, approved
</div><pre style="font-family: monospace,monospace; white-space: pre-wrap;">gsm/gsm0480: refactor and expose gsm0480_parse_facility_ie()<br><br>This function can be used when there is only a part of GSM 04.80<br>message available - Facility IE, e.g. when a message is carried<br>over GSUP/MAP. Let's expose it.<br><br>Refactoring includes the following:<br><br> - adding the 'gsm0480_' prefix;<br> - correcting inverted return value;<br> - cosmetic code style changes.<br><br>Change-Id: I623c39ffbe6cdee65eade8435a2faa04d0da193e<br>---<br>M include/osmocom/gsm/gsm0480.h<br>M src/gsm/gsm0480.c<br>M src/gsm/libosmogsm.map<br>M tests/ussd/ussd_test.c<br>M tests/ussd/ussd_test.ok<br>5 files changed, 81 insertions(+), 16 deletions(-)<br><br></pre><pre style="font-family: monospace,monospace; white-space: pre-wrap;"><span>diff --git a/include/osmocom/gsm/gsm0480.h b/include/osmocom/gsm/gsm0480.h</span><br><span>index b31f8a7..fafa1f4 100644</span><br><span>--- a/include/osmocom/gsm/gsm0480.h</span><br><span>+++ b/include/osmocom/gsm/gsm0480.h</span><br><span>@@ -93,6 +93,8 @@</span><br><span> </span><br><span> int gsm0480_extract_ie_by_tag(const struct gsm48_hdr *hdr, uint16_t msg_len,</span><br><span> uint8_t **ie, uint16_t *ie_len, uint8_t ie_tag);</span><br><span style="color: hsl(120, 100%, 40%);">+int gsm0480_parse_facility_ie(const uint8_t *facility_ie, uint16_t length,</span><br><span style="color: hsl(120, 100%, 40%);">+ struct ss_request *req);</span><br><span> int gsm0480_decode_ss_request(const struct gsm48_hdr *hdr, uint16_t len,</span><br><span> struct ss_request *request);</span><br><span> </span><br><span>diff --git a/src/gsm/gsm0480.c b/src/gsm/gsm0480.c</span><br><span>index dfd9877..300c0ed 100644</span><br><span>--- a/src/gsm/gsm0480.c</span><br><span>+++ b/src/gsm/gsm0480.c</span><br><span>@@ -201,8 +201,6 @@</span><br><span> struct ss_request *req);</span><br><span> static int parse_ss_info_elements(const uint8_t *ss_ie, uint16_t len,</span><br><span> struct ss_request *req);</span><br><span style="color: hsl(0, 100%, 40%);">-static int parse_facility_ie(const uint8_t *facility_ie, uint16_t length,</span><br><span style="color: hsl(0, 100%, 40%);">- struct ss_request *req);</span><br><span> static int parse_ss_invoke(const uint8_t *invoke_data, uint16_t length,</span><br><span> struct ss_request *req);</span><br><span> static int parse_ss_return_result(const uint8_t *rr_data, uint16_t length,</span><br><span>@@ -419,7 +417,7 @@</span><br><span> if (len - 1 < facility_length)</span><br><span> return 0;</span><br><span> </span><br><span style="color: hsl(0, 100%, 40%);">- return parse_facility_ie(ss_facility + 1, facility_length, req);</span><br><span style="color: hsl(120, 100%, 40%);">+ return !gsm0480_parse_facility_ie(ss_facility + 1, facility_length, req);</span><br><span> }</span><br><span> </span><br><span> static int parse_ss_info_elements(const uint8_t *ss_ie, uint16_t len,</span><br><span>@@ -445,7 +443,7 @@</span><br><span> case GSM48_IE_CAUSE:</span><br><span> break;</span><br><span> case GSM0480_IE_FACILITY:</span><br><span style="color: hsl(0, 100%, 40%);">- rc = parse_facility_ie(ss_ie + 2, iei_length, req);</span><br><span style="color: hsl(120, 100%, 40%);">+ rc = !gsm0480_parse_facility_ie(ss_ie + 2, iei_length, req);</span><br><span> break;</span><br><span> case GSM0480_IE_SS_VERSION:</span><br><span> break;</span><br><span>@@ -464,31 +462,40 @@</span><br><span> return rc;</span><br><span> }</span><br><span> </span><br><span style="color: hsl(0, 100%, 40%);">-static int parse_facility_ie(const uint8_t *facility_ie, uint16_t length,</span><br><span style="color: hsl(0, 100%, 40%);">- struct ss_request *req)</span><br><span style="color: hsl(120, 100%, 40%);">+/*! Parse the components of a given Facility IE</span><br><span style="color: hsl(120, 100%, 40%);">+ * \param[in] facility_ie The Facility IE</span><br><span style="color: hsl(120, 100%, 40%);">+ * \param[in] length The length of Facility IE</span><br><span style="color: hsl(120, 100%, 40%);">+ * \param[out] req Abstract representation of SS message</span><br><span style="color: hsl(120, 100%, 40%);">+ * \return 0 in case of success, otherwise -ERRNO</span><br><span style="color: hsl(120, 100%, 40%);">+ */</span><br><span style="color: hsl(120, 100%, 40%);">+int gsm0480_parse_facility_ie(const uint8_t *facility_ie, uint16_t length,</span><br><span style="color: hsl(120, 100%, 40%);">+ struct ss_request *req)</span><br><span> {</span><br><span style="color: hsl(0, 100%, 40%);">- int rc = 1;</span><br><span style="color: hsl(120, 100%, 40%);">+ uint8_t component_length;</span><br><span style="color: hsl(120, 100%, 40%);">+ uint8_t component_type;</span><br><span> uint8_t offset = 0;</span><br><span style="color: hsl(120, 100%, 40%);">+ int rc = 1;</span><br><span> </span><br><span style="color: hsl(120, 100%, 40%);">+ /* Iterate over components within IE */</span><br><span> while (offset + 2 <= length) {</span><br><span> /* Component Type tag - table 3.7 */</span><br><span style="color: hsl(0, 100%, 40%);">- uint8_t component_type = facility_ie[offset];</span><br><span style="color: hsl(0, 100%, 40%);">- uint8_t component_length = facility_ie[offset+1];</span><br><span style="color: hsl(120, 100%, 40%);">+ component_type = facility_ie[offset];</span><br><span style="color: hsl(120, 100%, 40%);">+ component_length = facility_ie[offset + 1];</span><br><span> </span><br><span style="color: hsl(0, 100%, 40%);">- /* size check */</span><br><span style="color: hsl(120, 100%, 40%);">+ /* Make sure that there is no overflow */</span><br><span> if (offset + 2 + component_length > length) {</span><br><span> LOGP(0, LOGL_ERROR, "Component does not fit.\n");</span><br><span style="color: hsl(0, 100%, 40%);">- return 0;</span><br><span style="color: hsl(120, 100%, 40%);">+ return -EINVAL;</span><br><span> }</span><br><span> </span><br><span> switch (component_type) {</span><br><span> case GSM0480_CTYPE_INVOKE:</span><br><span style="color: hsl(0, 100%, 40%);">- rc &= parse_ss_invoke(facility_ie+2,</span><br><span style="color: hsl(120, 100%, 40%);">+ rc &= parse_ss_invoke(facility_ie + 2,</span><br><span> component_length,</span><br><span> req);</span><br><span> break;</span><br><span> case GSM0480_CTYPE_RETURN_RESULT:</span><br><span style="color: hsl(0, 100%, 40%);">- rc &= parse_ss_return_result(facility_ie+2,</span><br><span style="color: hsl(120, 100%, 40%);">+ rc &= parse_ss_return_result(facility_ie + 2,</span><br><span> component_length,</span><br><span> req);</span><br><span> break;</span><br><span>@@ -502,10 +509,17 @@</span><br><span> rc = 0;</span><br><span> break;</span><br><span> }</span><br><span style="color: hsl(0, 100%, 40%);">- offset += (component_length+2);</span><br><span style="color: hsl(0, 100%, 40%);">- };</span><br><span> </span><br><span style="color: hsl(0, 100%, 40%);">- return rc;</span><br><span style="color: hsl(120, 100%, 40%);">+ offset += (component_length + 2);</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ /**</span><br><span style="color: hsl(120, 100%, 40%);">+ * The internal functions are using inverted return</span><br><span style="color: hsl(120, 100%, 40%);">+ * codes, where '0' means error/failure. While a</span><br><span style="color: hsl(120, 100%, 40%);">+ * common approach is to return negative errno in</span><br><span style="color: hsl(120, 100%, 40%);">+ * case of any failure, and '0' if all is ok.</span><br><span style="color: hsl(120, 100%, 40%);">+ */</span><br><span style="color: hsl(120, 100%, 40%);">+ return (rc == 0) ? -EINVAL : 0;</span><br><span> }</span><br><span> </span><br><span> /* Parse an Invoke component - see table 3.3 */</span><br><span>diff --git a/src/gsm/libosmogsm.map b/src/gsm/libosmogsm.map</span><br><span>index 4aaed46..0a6742c 100644</span><br><span>--- a/src/gsm/libosmogsm.map</span><br><span>+++ b/src/gsm/libosmogsm.map</span><br><span>@@ -90,6 +90,7 @@</span><br><span> gsm0480_create_ussd_notify;</span><br><span> gsm0480_create_ussd_release_complete;</span><br><span> gsm0480_extract_ie_by_tag;</span><br><span style="color: hsl(120, 100%, 40%);">+gsm0480_parse_facility_ie;</span><br><span> gsm0480_decode_ussd_request;</span><br><span> gsm0480_decode_ss_request;</span><br><span> gsm0480_wrap_facility;</span><br><span>diff --git a/tests/ussd/ussd_test.c b/tests/ussd/ussd_test.c</span><br><span>index 23fd739..8025071 100644</span><br><span>--- a/tests/ussd/ussd_test.c</span><br><span>+++ b/tests/ussd/ussd_test.c</span><br><span>@@ -188,6 +188,43 @@</span><br><span> printf("\n");</span><br><span> }</span><br><span> </span><br><span style="color: hsl(120, 100%, 40%);">+static void test_parse_facility_ie(void)</span><br><span style="color: hsl(120, 100%, 40%);">+{</span><br><span style="color: hsl(120, 100%, 40%);">+ struct ss_request req;</span><br><span style="color: hsl(120, 100%, 40%);">+ uint16_t ie_len;</span><br><span style="color: hsl(120, 100%, 40%);">+ uint8_t *ie;</span><br><span style="color: hsl(120, 100%, 40%);">+ int rc;</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ printf("[i] Testing gsm0480_parse_facility_ie()\n");</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ /* Extract Facility IE from FACILITY message */</span><br><span style="color: hsl(120, 100%, 40%);">+ rc = gsm0480_extract_ie_by_tag((struct gsm48_hdr *) ussd_facility,</span><br><span style="color: hsl(120, 100%, 40%);">+ sizeof(ussd_facility), &ie, &ie_len, GSM0480_IE_FACILITY);</span><br><span style="color: hsl(120, 100%, 40%);">+ OSMO_ASSERT(rc == 0);</span><br><span style="color: hsl(120, 100%, 40%);">+ OSMO_ASSERT(ie != NULL && ie_len > 0);</span><br><span style="color: hsl(120, 100%, 40%);">+ printf("[?] FACILITY message with Facility IE "</span><br><span style="color: hsl(120, 100%, 40%);">+ "(len=%u): %s\n", ie_len, osmo_hexdump(ie, ie_len));</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ /* Attempt to decode */</span><br><span style="color: hsl(120, 100%, 40%);">+ memset(&req, 0x00, sizeof(req));</span><br><span style="color: hsl(120, 100%, 40%);">+ rc = gsm0480_parse_facility_ie(ie, ie_len, &req);</span><br><span style="color: hsl(120, 100%, 40%);">+ OSMO_ASSERT(rc == 0);</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ /* Verify expected vs decoded data */</span><br><span style="color: hsl(120, 100%, 40%);">+ printf("[?] InvokeID: expected 0x%02x, decoded 0x%02x\n",</span><br><span style="color: hsl(120, 100%, 40%);">+ 0x01, req.invoke_id);</span><br><span style="color: hsl(120, 100%, 40%);">+ printf("[?] Operation code: expected 0x%02x, decoded 0x%02x\n",</span><br><span style="color: hsl(120, 100%, 40%);">+ 0x3c, req.opcode);</span><br><span style="color: hsl(120, 100%, 40%);">+ printf("[?] Data Coding Scheme: expected 0x%02x, decoded 0x%02x\n",</span><br><span style="color: hsl(120, 100%, 40%);">+ 0x0f, req.ussd_data_dcs);</span><br><span style="color: hsl(120, 100%, 40%);">+ printf("[?] Data length: expected 0x%02x, decoded 0x%02x\n",</span><br><span style="color: hsl(120, 100%, 40%);">+ 0x01, req.ussd_data_len);</span><br><span style="color: hsl(120, 100%, 40%);">+ printf("[?] Data: expected %s, decoded %s\n", "32",</span><br><span style="color: hsl(120, 100%, 40%);">+ osmo_hexdump_nospc(req.ussd_data, req.ussd_data_len));</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ printf("\n");</span><br><span style="color: hsl(120, 100%, 40%);">+}</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span> int main(int argc, char **argv)</span><br><span> {</span><br><span> struct ss_request req;</span><br><span>@@ -201,6 +238,9 @@</span><br><span> /* Test gsm0480_extract_ie_by_tag() */</span><br><span> test_extract_ie_by_tag();</span><br><span> </span><br><span style="color: hsl(120, 100%, 40%);">+ /* Test gsm0480_parse_facility_ie() */</span><br><span style="color: hsl(120, 100%, 40%);">+ test_parse_facility_ie();</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span> memset(&req, 0, sizeof(req));</span><br><span> gsm0480_decode_ss_request((struct gsm48_hdr *) ussd_request,</span><br><span> sizeof(ussd_request), &req);</span><br><span>diff --git a/tests/ussd/ussd_test.ok b/tests/ussd/ussd_test.ok</span><br><span>index 8fa4348..1137080 100644</span><br><span>--- a/tests/ussd/ussd_test.ok</span><br><span>+++ b/tests/ussd/ussd_test.ok</span><br><span>@@ -4,6 +4,14 @@</span><br><span> [?] FACILITY message with Facility IE (len=18): a2 10 02 01 01 30 0b 02 01 3c 30 06 04 01 0f 04 01 32 </span><br><span> [?] RELEASE COMPLETE message with Facility IE (len=8): a3 06 02 01 05 02 01 24 </span><br><span> </span><br><span style="color: hsl(120, 100%, 40%);">+[i] Testing gsm0480_parse_facility_ie()</span><br><span style="color: hsl(120, 100%, 40%);">+[?] FACILITY message with Facility IE (len=18): a2 10 02 01 01 30 0b 02 01 3c 30 06 04 01 0f 04 01 32 </span><br><span style="color: hsl(120, 100%, 40%);">+[?] InvokeID: expected 0x01, decoded 0x01</span><br><span style="color: hsl(120, 100%, 40%);">+[?] Operation code: expected 0x3c, decoded 0x3c</span><br><span style="color: hsl(120, 100%, 40%);">+[?] Data Coding Scheme: expected 0x0f, decoded 0x0f</span><br><span style="color: hsl(120, 100%, 40%);">+[?] Data length: expected 0x01, decoded 0x01</span><br><span style="color: hsl(120, 100%, 40%);">+[?] Data: expected 32, decoded 32</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span> Tested if it still works. Text was: **321#</span><br><span> interrogateSS CFU text..'' code 33</span><br><span> Testing parsing a USSD request and truncated versions</span><br><span></span><br></pre><p>To view, visit <a href="https://gerrit.osmocom.org/9529">change 9529</a>. To unsubscribe, or for help writing mail filters, visit <a href="https://gerrit.osmocom.org/settings">settings</a>.</p><div itemscope itemtype="http://schema.org/EmailMessage"><div itemscope itemprop="action" itemtype="http://schema.org/ViewAction"><link itemprop="url" href="https://gerrit.osmocom.org/9529"/><meta itemprop="name" content="View Change"/></div></div>
<div style="display:none"> Gerrit-Project: libosmocore </div>
<div style="display:none"> Gerrit-Branch: master </div>
<div style="display:none"> Gerrit-MessageType: merged </div>
<div style="display:none"> Gerrit-Change-Id: I623c39ffbe6cdee65eade8435a2faa04d0da193e </div>
<div style="display:none"> Gerrit-Change-Number: 9529 </div>
<div style="display:none"> Gerrit-PatchSet: 2 </div>
<div style="display:none"> Gerrit-Owner: Vadim Yanitskiy <axilirator@gmail.com> </div>
<div style="display:none"> Gerrit-Reviewer: Harald Welte <laforge@gnumonks.org> </div>
<div style="display:none"> Gerrit-Reviewer: Jenkins Builder </div>