P2P2: Fragment P2P IE if subelements are too long in GO Negotiation

Add a function to fragment P2P/P2P2 IE exceeding 255 bytes in size and
use this for P2P IE in GO Negotiation frames in preparation for P2P2.

Signed-off-by: Shivani Baranwal <quic_shivbara@quicinc.com>

diff --git a/src/p2p/p2p_build.c b/src/p2p/p2p_build.c
index 78ef2dbcd039731175be6d08c35658363b129c04..ddadd34bc5a1128c05abca3c5b9f08aae5717767 100644 (file)
--- a/src/p2p/p2p_build.c
+++ b/src/p2p/p2p_build.c
@@ -957,3 +957,37 @@ int p2p_build_wps_ie(struct p2p_data *p2p, struct wpabuf *buf, int pw_id,
 
        return 0;
 }
+
+
+struct wpabuf * p2p_encaps_ie(const struct wpabuf *subelems, u32 ie_type)
+{
+       struct wpabuf *ie;
+       const u8 *pos, *end;
+       size_t len;
+
+       if (!subelems)
+               return NULL;
+
+       len = wpabuf_len(subelems) + 1000;
+
+       ie = wpabuf_alloc(len);
+       if (!ie)
+               return NULL;
+
+       pos = wpabuf_head(subelems);
+       end = pos + wpabuf_len(subelems);
+
+       while (end > pos) {
+               size_t frag_len = end - pos;
+
+               if (frag_len > 251)
+                       frag_len = 251;
+               wpabuf_put_u8(ie, WLAN_EID_VENDOR_SPECIFIC);
+               wpabuf_put_u8(ie, 4 + frag_len);
+               wpabuf_put_be32(ie, ie_type);
+               wpabuf_put_data(ie, pos, frag_len);
+               pos += frag_len;
+       }
+
+       return ie;
+}

diff --git a/src/p2p/p2p_go_neg.c b/src/p2p/p2p_go_neg.c
index 1cd7d06d3a0049a2a80e97e4a2e35a5dddc64b2c..970bb39389d6b1530f5ab95dd643e8a16e0461eb 100644 (file)
--- a/src/p2p/p2p_go_neg.c
+++ b/src/p2p/p2p_go_neg.c
@@ -139,7 +139,7 @@ static struct wpabuf * p2p_build_go_neg_req(struct p2p_data *p2p,
                                            struct p2p_device *peer)
 {
        struct wpabuf *buf;
-       u8 *len;
+       struct wpabuf *subelems;
        u8 group_capab;
        size_t extra = 0;
        u16 pw_id;
@@ -159,7 +159,12 @@ static struct wpabuf * p2p_build_go_neg_req(struct p2p_data *p2p,
 
        p2p_buf_add_public_action_hdr(buf, P2P_GO_NEG_REQ, peer->dialog_token);
 
-       len = p2p_buf_add_ie_hdr(buf);
+       subelems = wpabuf_alloc(500);
+       if (!subelems) {
+               wpabuf_free(buf);
+               return NULL;
+       }
+
        group_capab = 0;
        if (peer->flags & P2P_DEV_PREFER_PERSISTENT_GROUP) {
                group_capab |= P2P_GROUP_CAPAB_PERSISTENT_GROUP;
@@ -170,17 +175,20 @@ static struct wpabuf * p2p_build_go_neg_req(struct p2p_data *p2p,
                group_capab |= P2P_GROUP_CAPAB_CROSS_CONN;
        if (p2p->cfg->p2p_intra_bss)
                group_capab |= P2P_GROUP_CAPAB_INTRA_BSS_DIST;
-       p2p_buf_add_capability(buf, p2p->dev_capab &
+       p2p_buf_add_capability(subelems, p2p->dev_capab &
                               ~P2P_DEV_CAPAB_CLIENT_DISCOVERABILITY,
                               group_capab);
-       p2p_buf_add_go_intent(buf, (p2p->go_intent << 1) | peer->tie_breaker);
-       p2p_buf_add_config_timeout(buf, p2p->go_timeout, p2p->client_timeout);
-       p2p_buf_add_listen_channel(buf, p2p->cfg->country, p2p->cfg->reg_class,
+       p2p_buf_add_go_intent(subelems,
+                             (p2p->go_intent << 1) | peer->tie_breaker);
+       p2p_buf_add_config_timeout(subelems, p2p->go_timeout,
+                                  p2p->client_timeout);
+       p2p_buf_add_listen_channel(subelems, p2p->cfg->country,
+                                  p2p->cfg->reg_class,
                                   p2p->cfg->channel);
        if (p2p->ext_listen_interval)
-               p2p_buf_add_ext_listen_timing(buf, p2p->ext_listen_period,
+               p2p_buf_add_ext_listen_timing(subelems, p2p->ext_listen_period,
                                              p2p->ext_listen_interval);
-       p2p_buf_add_intended_addr(buf, p2p->intended_addr);
+       p2p_buf_add_intended_addr(subelems, p2p->intended_addr);
        is_6ghz_capab = is_p2p_6ghz_capable(p2p) &&
                p2p_is_peer_6ghz_capab(p2p, peer->info.p2p_device_addr);
        if (p2p->num_pref_freq) {
@@ -191,16 +199,15 @@ static struct wpabuf * p2p_build_go_neg_req(struct p2p_data *p2p,
                                        p2p->num_pref_freq, &pref_chanlist, go);
                p2p_channels_dump(p2p, "channel list after filtering",
                                  &pref_chanlist);
-               p2p_buf_add_channel_list(buf, p2p->cfg->country,
+               p2p_buf_add_channel_list(subelems, p2p->cfg->country,
                                         &pref_chanlist, is_6ghz_capab);
        } else {
-               p2p_buf_add_channel_list(buf, p2p->cfg->country,
+               p2p_buf_add_channel_list(subelems, p2p->cfg->country,
                                         &p2p->channels, is_6ghz_capab);
        }
-       p2p_buf_add_device_info(buf, p2p, peer);
-       p2p_buf_add_operating_channel(buf, p2p->cfg->country,
+       p2p_buf_add_device_info(subelems, p2p, peer);
+       p2p_buf_add_operating_channel(subelems, p2p->cfg->country,
                                      p2p->op_reg_class, p2p->op_channel);
-       p2p_buf_update_ie_hdr(buf, len);
 
        p2p_buf_add_pref_channel_list(buf, p2p->pref_freq_list,
                                      p2p->num_pref_freq);
@@ -211,6 +218,7 @@ static struct wpabuf * p2p_build_go_neg_req(struct p2p_data *p2p,
                pw_id = peer->oob_pw_id;
        if (p2p_build_wps_ie(p2p, buf, pw_id, 0) < 0) {
                p2p_dbg(p2p, "Failed to build WPS IE for GO Negotiation Request");
+               wpabuf_free(subelems);
                wpabuf_free(buf);
                return NULL;
        }
@@ -223,6 +231,8 @@ static struct wpabuf * p2p_build_go_neg_req(struct p2p_data *p2p,
        if (p2p->vendor_elem && p2p->vendor_elem[VENDOR_ELEM_P2P_GO_NEG_REQ])
                wpabuf_put_buf(buf, p2p->vendor_elem[VENDOR_ELEM_P2P_GO_NEG_REQ]);
 
+       buf = wpabuf_concat(buf, p2p_encaps_ie(subelems, P2P_IE_VENDOR_TYPE));
+       wpabuf_free(subelems);
        return buf;
 }
 
@@ -293,7 +303,7 @@ static struct wpabuf * p2p_build_go_neg_resp(struct p2p_data *p2p,
                                             u8 tie_breaker)
 {
        struct wpabuf *buf;
-       u8 *len;
+       struct wpabuf *subelems;
        u8 group_capab;
        size_t extra = 0;
        u16 pw_id;
@@ -316,8 +326,13 @@ static struct wpabuf * p2p_build_go_neg_resp(struct p2p_data *p2p,
 
        p2p_buf_add_public_action_hdr(buf, P2P_GO_NEG_RESP, dialog_token);
 
-       len = p2p_buf_add_ie_hdr(buf);
-       p2p_buf_add_status(buf, status);
+       subelems = wpabuf_alloc(500);
+       if (!subelems) {
+               wpabuf_free(buf);
+               return NULL;
+       }
+
+       p2p_buf_add_status(subelems, status);
        group_capab = 0;
        if (peer && peer->go_state == LOCAL_GO) {
                if (peer->flags & P2P_DEV_PREFER_PERSISTENT_GROUP) {
@@ -331,24 +346,26 @@ static struct wpabuf * p2p_build_go_neg_resp(struct p2p_data *p2p,
                if (p2p->cfg->p2p_intra_bss)
                        group_capab |= P2P_GROUP_CAPAB_INTRA_BSS_DIST;
        }
-       p2p_buf_add_capability(buf, p2p->dev_capab &
+       p2p_buf_add_capability(subelems, p2p->dev_capab &
                               ~P2P_DEV_CAPAB_CLIENT_DISCOVERABILITY,
                               group_capab);
-       p2p_buf_add_go_intent(buf, (p2p->go_intent << 1) | tie_breaker);
-       p2p_buf_add_config_timeout(buf, p2p->go_timeout, p2p->client_timeout);
+       p2p_buf_add_go_intent(subelems, (p2p->go_intent << 1) | tie_breaker);
+       p2p_buf_add_config_timeout(subelems, p2p->go_timeout,
+                                  p2p->client_timeout);
        if (p2p->override_pref_op_class) {
                p2p_dbg(p2p, "Override operating channel preference");
-               p2p_buf_add_operating_channel(buf, p2p->cfg->country,
+               p2p_buf_add_operating_channel(subelems, p2p->cfg->country,
                                              p2p->override_pref_op_class,
                                              p2p->override_pref_channel);
        } else if (peer && peer->go_state == REMOTE_GO && !p2p->num_pref_freq) {
                p2p_dbg(p2p, "Omit Operating Channel attribute");
        } else {
-               p2p_buf_add_operating_channel(buf, p2p->cfg->country,
+               p2p_buf_add_operating_channel(subelems, p2p->cfg->country,
                                              p2p->op_reg_class,
                                              p2p->op_channel);
        }
-       p2p_buf_add_intended_addr(buf, p2p->intended_addr);
+       p2p_buf_add_intended_addr(subelems, p2p->intended_addr);
+
        if (p2p->num_pref_freq) {
                bool go = (peer && peer->go_state == LOCAL_GO) ||
                        p2p->go_intent == 15;
@@ -362,12 +379,12 @@ static struct wpabuf * p2p_build_go_neg_resp(struct p2p_data *p2p,
                                  p2p->allow_6ghz);
        }
        if (status || peer == NULL) {
-               p2p_buf_add_channel_list(buf, p2p->cfg->country,
+               p2p_buf_add_channel_list(subelems, p2p->cfg->country,
                                         &pref_chanlist, false);
        } else if (peer->go_state == REMOTE_GO) {
                is_6ghz_capab = is_p2p_6ghz_capable(p2p) &&
                        p2p_is_peer_6ghz_capab(p2p, peer->info.p2p_device_addr);
-               p2p_buf_add_channel_list(buf, p2p->cfg->country,
+               p2p_buf_add_channel_list(subelems, p2p->cfg->country,
                                         &pref_chanlist, is_6ghz_capab);
        } else {
                struct p2p_channels res;
@@ -376,15 +393,14 @@ static struct wpabuf * p2p_build_go_neg_resp(struct p2p_data *p2p,
                        p2p_is_peer_6ghz_capab(p2p, peer->info.p2p_device_addr);
                p2p_channels_intersect(&pref_chanlist, &peer->channels,
                                       &res);
-               p2p_buf_add_channel_list(buf, p2p->cfg->country, &res,
-                                      is_6ghz_capab);
+               p2p_buf_add_channel_list(subelems, p2p->cfg->country, &res,
+                                        is_6ghz_capab);
        }
-       p2p_buf_add_device_info(buf, p2p, peer);
+       p2p_buf_add_device_info(subelems, p2p, peer);
        if (peer && peer->go_state == LOCAL_GO) {
-               p2p_buf_add_group_id(buf, p2p->cfg->dev_addr, p2p->ssid,
+               p2p_buf_add_group_id(subelems, p2p->cfg->dev_addr, p2p->ssid,
                                     p2p->ssid_len);
        }
-       p2p_buf_update_ie_hdr(buf, len);
 
        /* WPS IE with Device Password ID attribute */
        pw_id = p2p_wps_method_pw_id(peer ? peer->wps_method : WPS_NOT_READY);
@@ -392,6 +408,7 @@ static struct wpabuf * p2p_build_go_neg_resp(struct p2p_data *p2p,
                pw_id = peer->oob_pw_id;
        if (p2p_build_wps_ie(p2p, buf, pw_id, 0) < 0) {
                p2p_dbg(p2p, "Failed to build WPS IE for GO Negotiation Response");
+               wpabuf_free(subelems);
                wpabuf_free(buf);
                return NULL;
        }
@@ -404,6 +421,8 @@ static struct wpabuf * p2p_build_go_neg_resp(struct p2p_data *p2p,
        if (p2p->vendor_elem && p2p->vendor_elem[VENDOR_ELEM_P2P_GO_NEG_RESP])
                wpabuf_put_buf(buf, p2p->vendor_elem[VENDOR_ELEM_P2P_GO_NEG_RESP]);
 
+       buf = wpabuf_concat(buf, p2p_encaps_ie(subelems, P2P_IE_VENDOR_TYPE));
+       wpabuf_free(subelems);
        return buf;
 }
 
@@ -1165,7 +1184,7 @@ static struct wpabuf * p2p_build_go_neg_conf(struct p2p_data *p2p,
                                             const u8 *resp_chan, int go)
 {
        struct wpabuf *buf;
-       u8 *len;
+       struct wpabuf *subelems;
        struct p2p_channels res;
        u8 group_capab;
        size_t extra = 0;
@@ -1187,8 +1206,13 @@ static struct wpabuf * p2p_build_go_neg_conf(struct p2p_data *p2p,
 
        p2p_buf_add_public_action_hdr(buf, P2P_GO_NEG_CONF, dialog_token);
 
-       len = p2p_buf_add_ie_hdr(buf);
-       p2p_buf_add_status(buf, status);
+       subelems = wpabuf_alloc(500);
+       if (!subelems) {
+               wpabuf_free(buf);
+               return NULL;
+       }
+
+       p2p_buf_add_status(subelems, status);
        group_capab = 0;
        if (peer->go_state == LOCAL_GO) {
                if (peer->flags & P2P_DEV_PREFER_PERSISTENT_GROUP) {
@@ -1202,25 +1226,26 @@ static struct wpabuf * p2p_build_go_neg_conf(struct p2p_data *p2p,
                if (p2p->cfg->p2p_intra_bss)
                        group_capab |= P2P_GROUP_CAPAB_INTRA_BSS_DIST;
        }
-       p2p_buf_add_capability(buf, p2p->dev_capab &
+       p2p_buf_add_capability(subelems, p2p->dev_capab &
                               ~P2P_DEV_CAPAB_CLIENT_DISCOVERABILITY,
                               group_capab);
        if (go || resp_chan == NULL)
-               p2p_buf_add_operating_channel(buf, p2p->cfg->country,
+               p2p_buf_add_operating_channel(subelems, p2p->cfg->country,
                                              p2p->op_reg_class,
                                              p2p->op_channel);
        else
-               p2p_buf_add_operating_channel(buf, (const char *) resp_chan,
+               p2p_buf_add_operating_channel(subelems,
+                                             (const char *) resp_chan,
                                              resp_chan[3], resp_chan[4]);
        p2p_channels_intersect(&p2p->channels, &peer->channels, &res);
        is_6ghz_capab = is_p2p_6ghz_capable(p2p) &&
                p2p_is_peer_6ghz_capab(p2p, peer->info.p2p_device_addr);
-       p2p_buf_add_channel_list(buf, p2p->cfg->country, &res, is_6ghz_capab);
+       p2p_buf_add_channel_list(subelems, p2p->cfg->country, &res,
+                                is_6ghz_capab);
        if (go) {
-               p2p_buf_add_group_id(buf, p2p->cfg->dev_addr, p2p->ssid,
+               p2p_buf_add_group_id(subelems, p2p->cfg->dev_addr, p2p->ssid,
                                     p2p->ssid_len);
        }
-       p2p_buf_update_ie_hdr(buf, len);
 
 #ifdef CONFIG_WIFI_DISPLAY
        if (p2p->wfd_ie_go_neg)
@@ -1230,6 +1255,8 @@ static struct wpabuf * p2p_build_go_neg_conf(struct p2p_data *p2p,
        if (p2p->vendor_elem && p2p->vendor_elem[VENDOR_ELEM_P2P_GO_NEG_CONF])
                wpabuf_put_buf(buf, p2p->vendor_elem[VENDOR_ELEM_P2P_GO_NEG_CONF]);
 
+       buf = wpabuf_concat(buf, p2p_encaps_ie(subelems, P2P_IE_VENDOR_TYPE));
+       wpabuf_free(subelems);
        return buf;
 }
 

diff --git a/src/p2p/p2p_i.h b/src/p2p/p2p_i.h
index 5f150b3bd6d2d4ccec68be5d164b5ee2eecd868a..409aacca6b099936eba2d0c02ba11f169560600a 100644 (file)
--- a/src/p2p/p2p_i.h
+++ b/src/p2p/p2p_i.h
@@ -872,6 +872,7 @@ int p2p_build_wps_ie(struct p2p_data *p2p, struct wpabuf *buf, int pw_id,
 void p2p_buf_add_pref_channel_list(struct wpabuf *buf,
                                   const struct weighted_pcl *pref_freq_list,
                                   unsigned int size);
+struct wpabuf * p2p_encaps_ie(const struct wpabuf *subelems, u32 ie_type);
 
 /* p2p_sd.c */
 struct p2p_sd_query * p2p_pending_sd_req(struct p2p_data *p2p,