<p>pespin <strong>submitted</strong> this change.</p><p><a href="https://gerrit.osmocom.org/c/libosmo-netif/+/26435">View Change</a></p><div style="white-space:pre-wrap">Approvals:
laforge: Looks good to me, but someone else must approve
osmith: Looks good to me, but someone else must approve
pespin: Looks good to me, approved
Jenkins Builder: Verified
</div><pre style="font-family: monospace,monospace; white-space: pre-wrap;">prim: Add internal CTL SAPI to negotiate SAP versions<br><br>This commits adds a generic mechanism for applications to validate<br>support for SAPs and specific versions of them.<br><br>A new special SAPI is introduced to manage inbound control messages for<br>the protocol.<br>In that SAPI a new primitive HELLO.req/.cnf is added to negotiate<br>support for versions of any given SAP.<br>The idea is that the client upon connecting submits a HELLO.req(SAP,<br>VER) for each SAP it plans to use, including the version of the special<br>CTL SAPI itself (preferrably to be checked first).<br>Upon receiving such a message, osmo_prim_srv handles it using a special<br>path, which ends up calling the user provided rx_sapi_version_cb(SAP,<br>VER). In there, the user can either:<br>* Accept the version (return same VER value)<br>* Reject the requested version but propose another candidate version<br> (return some positive VER value other than received VER). In this<br> case, the client can decide whether to request another VER or close the<br> connection.<br>* Reject the proposed version and close the connection.<br><br>Change-Id: I0c2d92cfdb5433e3caab51d712fd947d51eeef23<br>---<br>M include/osmocom/netif/prim.h<br>M src/prim.c<br>2 files changed, 122 insertions(+), 3 deletions(-)<br><br></pre><pre style="font-family: monospace,monospace; white-space: pre-wrap;"><span>diff --git a/include/osmocom/netif/prim.h b/include/osmocom/netif/prim.h</span><br><span>index 4f17622..78406dd 100644</span><br><span>--- a/include/osmocom/netif/prim.h</span><br><span>+++ b/include/osmocom/netif/prim.h</span><br><span>@@ -31,6 +31,15 @@</span><br><span> /*! oph and related msgb is owned by srv and wll be freed after the callback returns. */</span><br><span> typedef int (*osmo_prim_srv_rx_cb)(struct osmo_prim_srv *prim_srv, struct osmo_prim_hdr *oph);</span><br><span> </span><br><span style="color: hsl(120, 100%, 40%);">+/*! Return value:</span><br><span style="color: hsl(120, 100%, 40%);">+ * RET=rem_version: Accept the version</span><br><span style="color: hsl(120, 100%, 40%);">+ * RET!=rem_version && RET > 0: Reject the requested version but propose another candidate version</span><br><span style="color: hsl(120, 100%, 40%);">+ * In this case, the client can decide whether to request another VER</span><br><span style="color: hsl(120, 100%, 40%);">+ * or close the connection.</span><br><span style="color: hsl(120, 100%, 40%);">+ * RET<0: Reject the proposed version and close the connection.</span><br><span style="color: hsl(120, 100%, 40%);">+ */</span><br><span style="color: hsl(120, 100%, 40%);">+typedef int (*osmo_prim_srv_rx_sapi_version)(struct osmo_prim_srv *prim_srv, uint32_t sapi, uint16_t rem_version);</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span> struct osmo_prim_hdr *osmo_prim_msgb_alloc(unsigned int sap, unsigned int primitive,</span><br><span> enum osmo_prim_operation operation, size_t alloc_len);</span><br><span> </span><br><span>@@ -43,6 +52,7 @@</span><br><span> void osmo_prim_srv_link_set_log_category(struct osmo_prim_srv_link *prim_link, int log_cat);</span><br><span> void osmo_prim_srv_link_set_opened_conn_cb(struct osmo_prim_srv_link *prim_link, osmo_prim_srv_conn_cb opened_conn_cb);</span><br><span> void osmo_prim_srv_link_set_closed_conn_cb(struct osmo_prim_srv_link *prim_link, osmo_prim_srv_conn_cb closed_conn_cb);</span><br><span style="color: hsl(120, 100%, 40%);">+void osmo_prim_srv_link_set_rx_sapi_version_cb(struct osmo_prim_srv_link *prim_link, osmo_prim_srv_rx_sapi_version rx_sapi_version_cb);</span><br><span> void osmo_prim_srv_link_set_rx_cb(struct osmo_prim_srv_link *prim_link, osmo_prim_srv_rx_cb rx_cb);</span><br><span> void osmo_prim_srv_link_set_rx_msgb_alloc_len(struct osmo_prim_srv_link *prim_link, size_t alloc_len);</span><br><span> int osmo_prim_srv_link_open(struct osmo_prim_srv_link *prim_link);</span><br><span>diff --git a/src/prim.c b/src/prim.c</span><br><span>index 6c6da6e..5189c4c 100644</span><br><span>--- a/src/prim.c</span><br><span>+++ b/src/prim.c</span><br><span>@@ -82,6 +82,7 @@</span><br><span> struct osmo_stream_srv_link *stream;</span><br><span> osmo_prim_srv_conn_cb opened_conn_cb;</span><br><span> osmo_prim_srv_conn_cb closed_conn_cb;</span><br><span style="color: hsl(120, 100%, 40%);">+ osmo_prim_srv_rx_sapi_version rx_sapi_version_cb;</span><br><span> osmo_prim_srv_rx_cb rx_cb;</span><br><span> size_t rx_msgb_alloc_len;</span><br><span> };</span><br><span>@@ -93,10 +94,107 @@</span><br><span> };</span><br><span> </span><br><span> /******************************</span><br><span style="color: hsl(120, 100%, 40%);">+ * CONTROL SAP</span><br><span style="color: hsl(120, 100%, 40%);">+ ******************************/</span><br><span style="color: hsl(120, 100%, 40%);">+#define OSMO_PRIM_CTL_SAPI 0xffffffff</span><br><span style="color: hsl(120, 100%, 40%);">+#define OSMO_PRIM_CTL_API_VERSION 0</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+enum sap_ctl_prim_type {</span><br><span style="color: hsl(120, 100%, 40%);">+ SAP_CTL_PRIM_HELLO,</span><br><span style="color: hsl(120, 100%, 40%);">+ _SAP_CTL_PRIM_MAX</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%);">+const struct value_string sap_ctl_prim_type_names[] = {</span><br><span style="color: hsl(120, 100%, 40%);">+ OSMO_VALUE_STRING(SAP_CTL_PRIM_HELLO),</span><br><span style="color: hsl(120, 100%, 40%);">+ { 0, NULL }</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%);">+/* HNB_CTL_PRIM_HELLO.ind, UL */</span><br><span style="color: hsl(120, 100%, 40%);">+struct sap_ctl_hello_param {</span><br><span style="color: hsl(120, 100%, 40%);">+ uint32_t sapi; /* SAPI for which we negotiate version */</span><br><span style="color: hsl(120, 100%, 40%);">+ uint16_t api_version; /* The intended version */</span><br><span style="color: hsl(120, 100%, 40%);">+} __attribute__ ((packed));</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+struct sap_ctl_prim {</span><br><span style="color: hsl(120, 100%, 40%);">+ struct osmo_prim_hdr hdr;</span><br><span style="color: hsl(120, 100%, 40%);">+ union {</span><br><span style="color: hsl(120, 100%, 40%);">+ struct sap_ctl_hello_param hello_req;</span><br><span style="color: hsl(120, 100%, 40%);">+ struct sap_ctl_hello_param hello_cnf;</span><br><span style="color: hsl(120, 100%, 40%);">+ } u;</span><br><span style="color: hsl(120, 100%, 40%);">+} __attribute__ ((packed));</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+static struct sap_ctl_prim *_sap_ctl_makeprim_hello_cnf(uint32_t sapi, uint16_t api_version)</span><br><span style="color: hsl(120, 100%, 40%);">+{</span><br><span style="color: hsl(120, 100%, 40%);">+ struct sap_ctl_prim *ctl_prim;</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ ctl_prim = (struct sap_ctl_prim *)osmo_prim_msgb_alloc(</span><br><span style="color: hsl(120, 100%, 40%);">+ OSMO_PRIM_CTL_SAPI, SAP_CTL_PRIM_HELLO, PRIM_OP_CONFIRM,</span><br><span style="color: hsl(120, 100%, 40%);">+ sizeof(struct osmo_prim_hdr) + sizeof(struct sap_ctl_hello_param));</span><br><span style="color: hsl(120, 100%, 40%);">+ msgb_put(ctl_prim->hdr.msg, sizeof(struct sap_ctl_hello_param));</span><br><span style="color: hsl(120, 100%, 40%);">+ ctl_prim->u.hello_cnf.sapi = sapi;</span><br><span style="color: hsl(120, 100%, 40%);">+ ctl_prim->u.hello_cnf.api_version = api_version;</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ return ctl_prim;</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> * osmo_prim_srv</span><br><span> ******************************/</span><br><span> #define LOGSRV(srv, lvl, fmt, args...) LOGP((srv)->link->log_cat, lvl, fmt, ## args)</span><br><span> </span><br><span style="color: hsl(120, 100%, 40%);">+static int _srv_sap_ctl_rx_hello_req(struct osmo_prim_srv *prim_srv, struct sap_ctl_hello_param *hello_ind)</span><br><span style="color: hsl(120, 100%, 40%);">+{</span><br><span style="color: hsl(120, 100%, 40%);">+ struct sap_ctl_prim *prim_resp;</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%);">+ LOGSRV(prim_srv, LOGL_INFO, "Rx CTL-HELLO.req SAPI=%u API_VERSION=%u\n", hello_ind->sapi, hello_ind->api_version);</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ if (hello_ind->sapi == OSMO_PRIM_CTL_SAPI)</span><br><span style="color: hsl(120, 100%, 40%);">+ rc = hello_ind->api_version == OSMO_PRIM_CTL_API_VERSION ? OSMO_PRIM_CTL_API_VERSION : -1;</span><br><span style="color: hsl(120, 100%, 40%);">+ else if (prim_srv->link->rx_sapi_version_cb)</span><br><span style="color: hsl(120, 100%, 40%);">+ rc = prim_srv->link->rx_sapi_version_cb(prim_srv, hello_ind->sapi, hello_ind->api_version);</span><br><span style="color: hsl(120, 100%, 40%);">+ else /* Accept whatever version by default: */</span><br><span style="color: hsl(120, 100%, 40%);">+ rc = hello_ind->api_version;</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span style="color: hsl(120, 100%, 40%);">+ if (rc < 0) {</span><br><span style="color: hsl(120, 100%, 40%);">+ LOGSRV(prim_srv, LOGL_ERROR,</span><br><span style="color: hsl(120, 100%, 40%);">+ "SAPI=%u API_VERSION=%u not supported! destroying connection\n",</span><br><span style="color: hsl(120, 100%, 40%);">+ hello_ind->sapi, hello_ind->api_version);</span><br><span style="color: hsl(120, 100%, 40%);">+ osmo_stream_srv_set_flush_and_destroy(prim_srv->stream);</span><br><span style="color: hsl(120, 100%, 40%);">+ return rc;</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+ prim_resp = _sap_ctl_makeprim_hello_cnf(hello_ind->sapi, (uint16_t)rc);</span><br><span style="color: hsl(120, 100%, 40%);">+ LOGSRV(prim_srv, LOGL_INFO, "Tx CTL-HELLO.cnf SAPI=%u API_VERSION=%u\n",</span><br><span style="color: hsl(120, 100%, 40%);">+ hello_ind->sapi, prim_resp->u.hello_cnf.api_version);</span><br><span style="color: hsl(120, 100%, 40%);">+ osmo_prim_srv_send(prim_srv, prim_resp->hdr.msg);</span><br><span style="color: hsl(120, 100%, 40%);">+ return rc;</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%);">+static int _srv_sap_ctl_rx(struct osmo_prim_srv *prim_srv, struct osmo_prim_hdr *oph)</span><br><span style="color: hsl(120, 100%, 40%);">+{</span><br><span style="color: hsl(120, 100%, 40%);">+ switch (oph->operation) {</span><br><span style="color: hsl(120, 100%, 40%);">+ case PRIM_OP_REQUEST:</span><br><span style="color: hsl(120, 100%, 40%);">+ switch (oph->primitive) {</span><br><span style="color: hsl(120, 100%, 40%);">+ case SAP_CTL_PRIM_HELLO:</span><br><span style="color: hsl(120, 100%, 40%);">+ return _srv_sap_ctl_rx_hello_req(prim_srv, (struct sap_ctl_hello_param *)msgb_data(oph->msg));</span><br><span style="color: hsl(120, 100%, 40%);">+ default:</span><br><span style="color: hsl(120, 100%, 40%);">+ LOGSRV(prim_srv, LOGL_ERROR, "Rx unknown CTL SAP primitive %u (len=%u)\n",</span><br><span style="color: hsl(120, 100%, 40%);">+ oph->primitive, msgb_length(oph->msg));</span><br><span style="color: hsl(120, 100%, 40%);">+ return -EINVAL;</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span style="color: hsl(120, 100%, 40%);">+ break;</span><br><span style="color: hsl(120, 100%, 40%);">+ case PRIM_OP_RESPONSE:</span><br><span style="color: hsl(120, 100%, 40%);">+ case PRIM_OP_INDICATION:</span><br><span style="color: hsl(120, 100%, 40%);">+ case PRIM_OP_CONFIRM:</span><br><span style="color: hsl(120, 100%, 40%);">+ default:</span><br><span style="color: hsl(120, 100%, 40%);">+ LOGSRV(prim_srv, LOGL_ERROR, "Rx CTL SAP unexpected primitive operation %s-%s (len=%u)\n",</span><br><span style="color: hsl(120, 100%, 40%);">+ get_value_string(sap_ctl_prim_type_names, oph->primitive),</span><br><span style="color: hsl(120, 100%, 40%);">+ get_value_string(osmo_prim_op_names, oph->operation),</span><br><span style="color: hsl(120, 100%, 40%);">+ msgb_length(oph->msg));</span><br><span style="color: hsl(120, 100%, 40%);">+ return -EINVAL;</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> static int _osmo_prim_srv_read_cb(struct osmo_stream_srv *srv)</span><br><span> {</span><br><span> struct osmo_prim_srv *prim_srv = osmo_stream_srv_get_data(srv);</span><br><span>@@ -133,9 +231,15 @@</span><br><span> osmo_prim_init(&oph, pkth->sap, pkth->primitive, pkth->operation, msg);</span><br><span> msgb_pull(msg, sizeof(*pkth));</span><br><span> </span><br><span style="color: hsl(0, 100%, 40%);">- if (prim_srv->link->rx_cb)</span><br><span style="color: hsl(0, 100%, 40%);">- rc = prim_srv->link->rx_cb(prim_srv, &oph);</span><br><span style="color: hsl(0, 100%, 40%);">-</span><br><span style="color: hsl(120, 100%, 40%);">+ switch (oph.sap) {</span><br><span style="color: hsl(120, 100%, 40%);">+ case OSMO_PRIM_CTL_SAPI:</span><br><span style="color: hsl(120, 100%, 40%);">+ rc = _srv_sap_ctl_rx(prim_srv, &oph);</span><br><span style="color: hsl(120, 100%, 40%);">+ break;</span><br><span style="color: hsl(120, 100%, 40%);">+ default:</span><br><span style="color: hsl(120, 100%, 40%);">+ if (prim_srv->link->rx_cb)</span><br><span style="color: hsl(120, 100%, 40%);">+ rc = prim_srv->link->rx_cb(prim_srv, &oph);</span><br><span style="color: hsl(120, 100%, 40%);">+ break;</span><br><span style="color: hsl(120, 100%, 40%);">+ }</span><br><span> /* as we always synchronously process the message in _osmo_prim_srv_link_rx() and</span><br><span> * its callbacks, we can free the message here. */</span><br><span> msgb_free(msg);</span><br><span>@@ -325,6 +429,11 @@</span><br><span> prim_link->closed_conn_cb = closed_conn_cb;</span><br><span> }</span><br><span> </span><br><span style="color: hsl(120, 100%, 40%);">+void osmo_prim_srv_link_set_rx_sapi_version_cb(struct osmo_prim_srv_link *prim_link, osmo_prim_srv_rx_sapi_version rx_sapi_version_cb)</span><br><span style="color: hsl(120, 100%, 40%);">+{</span><br><span style="color: hsl(120, 100%, 40%);">+ prim_link->rx_sapi_version_cb = rx_sapi_version_cb;</span><br><span style="color: hsl(120, 100%, 40%);">+}</span><br><span style="color: hsl(120, 100%, 40%);">+</span><br><span> void osmo_prim_srv_link_set_rx_cb(struct osmo_prim_srv_link *prim_link, osmo_prim_srv_rx_cb rx_cb)</span><br><span> {</span><br><span> prim_link->rx_cb = rx_cb;</span><br><span></span><br></pre><p>To view, visit <a href="https://gerrit.osmocom.org/c/libosmo-netif/+/26435">change 26435</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/c/libosmo-netif/+/26435"/><meta itemprop="name" content="View Change"/></div></div>
<div style="display:none"> Gerrit-Project: libosmo-netif </div>
<div style="display:none"> Gerrit-Branch: master </div>
<div style="display:none"> Gerrit-Change-Id: I0c2d92cfdb5433e3caab51d712fd947d51eeef23 </div>
<div style="display:none"> Gerrit-Change-Number: 26435 </div>
<div style="display:none"> Gerrit-PatchSet: 9 </div>
<div style="display:none"> Gerrit-Owner: pespin <pespin@sysmocom.de> </div>
<div style="display:none"> Gerrit-Reviewer: Jenkins Builder </div>
<div style="display:none"> Gerrit-Reviewer: laforge <laforge@osmocom.org> </div>
<div style="display:none"> Gerrit-Reviewer: osmith <osmith@sysmocom.de> </div>
<div style="display:none"> Gerrit-Reviewer: pespin <pespin@sysmocom.de> </div>
<div style="display:none"> Gerrit-MessageType: merged </div>