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P2PS: Add Advertised Service Info into Probe Response frames

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Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
This commit is contained in:
Brian Gix 2014-09-05 17:06:25 +03:00 committed by Jouni Malinen
parent 9e7321eea4
commit 4660e73213
3 changed files with 170 additions and 0 deletions
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10
src/p2p/p2p.c
View file

@ -2116,6 +2116,9 @@ struct wpabuf * p2p_build_probe_resp_ies(struct p2p_data *p2p)
if (p2p->vendor_elem && p2p->vendor_elem[VENDOR_ELEM_PROBE_RESP_P2P])
extra += wpabuf_len(p2p->vendor_elem[VENDOR_ELEM_PROBE_RESP_P2P]);
if (p2p->query_count)
extra += MAX_SVC_ADV_IE_LEN;
buf = wpabuf_alloc(1000 + extra);
if (buf == NULL)
return NULL;
@ -2150,6 +2153,12 @@ struct wpabuf * p2p_build_probe_resp_ies(struct p2p_data *p2p)
p2p_buf_add_device_info(buf, p2p, NULL);
p2p_buf_update_ie_hdr(buf, len);
if (p2p->query_count) {
p2p_buf_add_service_instance(buf, p2p, p2p->query_count,
p2p->query_hash,
p2p->p2ps_adv_list);
}
return buf;
}
@ -2391,6 +2400,7 @@ p2p_probe_req_rx(struct p2p_data *p2p, const u8 *addr, const u8 *dst,
p2p_add_dev_from_probe_req(p2p, addr, ie, ie_len);
res = p2p_reply_probe(p2p, addr, dst, bssid, ie, ie_len);
p2p->query_count = 0;
if ((p2p->state == P2P_CONNECT || p2p->state == P2P_CONNECT_LISTEN) &&
p2p->go_neg_peer &&

150
src/p2p/p2p_build.c
View file

@ -404,6 +404,156 @@ void p2p_buf_add_advertisement_id(struct wpabuf *buf, u32 id, const u8 *mac)
}
void p2p_buf_add_service_instance(struct wpabuf *buf, struct p2p_data *p2p,
u8 hash_count, const u8 *hash,
struct p2ps_advertisement *adv_list)
{
struct p2ps_advertisement *adv;
struct wpabuf *tmp_buf;
u8 *tag_len = NULL, *ie_len = NULL;
size_t svc_len = 0, remaining = 0, total_len = 0;
if (!adv_list || !hash)
return;
/* Allocate temp buffer, allowing for overflow of 1 instance */
tmp_buf = wpabuf_alloc(MAX_SVC_ADV_IE_LEN + 256 + P2PS_HASH_LEN);
if (!tmp_buf)
return;
for (adv = adv_list; adv && total_len <= MAX_SVC_ADV_LEN;
adv = adv->next) {
u8 count = hash_count;
const u8 *test = hash;
while (count--) {
/* Check for wildcard */
if (os_memcmp(test, p2p->wild_card_hash,
P2PS_HASH_LEN) == 0) {
total_len = MAX_SVC_ADV_LEN + 1;
goto wild_hash;
}
if (os_memcmp(test, adv->hash, P2PS_HASH_LEN) == 0)
goto hash_match;
test += P2PS_HASH_LEN;
}
/* No matches found - Skip this Adv Instance */
continue;
hash_match:
if (!tag_len) {
tag_len = p2p_buf_add_ie_hdr(tmp_buf);
remaining = 255 - 4;
if (!ie_len) {
wpabuf_put_u8(tmp_buf,
P2P_ATTR_ADVERTISED_SERVICE);
ie_len = wpabuf_put(tmp_buf, sizeof(u16));
remaining -= (sizeof(u8) + sizeof(u16));
}
}
svc_len = os_strlen(adv->svc_name);
if (7 + svc_len + total_len > MAX_SVC_ADV_LEN) {
/* Can't fit... return wildcard */
total_len = MAX_SVC_ADV_LEN + 1;
break;
}
if (remaining <= (sizeof(adv->id) +
sizeof(adv->config_methods))) {
size_t front = remaining;
size_t back = (sizeof(adv->id) +
sizeof(adv->config_methods)) - front;
u8 holder[sizeof(adv->id) +
sizeof(adv->config_methods)];
/* This works even if front or back == 0 */
WPA_PUT_LE32(holder, adv->id);
WPA_PUT_BE16(&holder[sizeof(adv->id)],
adv->config_methods);
wpabuf_put_data(tmp_buf, holder, front);
p2p_buf_update_ie_hdr(tmp_buf, tag_len);
tag_len = p2p_buf_add_ie_hdr(tmp_buf);
wpabuf_put_data(tmp_buf, &holder[front], back);
remaining = 255 - (sizeof(adv->id) +
sizeof(adv->config_methods)) - back;
} else {
wpabuf_put_le32(tmp_buf, adv->id);
wpabuf_put_be16(tmp_buf, adv->config_methods);
remaining -= (sizeof(adv->id) +
sizeof(adv->config_methods));
}
/* We are guaranteed at least one byte for svc_len */
wpabuf_put_u8(tmp_buf, svc_len);
remaining -= sizeof(u8);
if (remaining < svc_len) {
size_t front = remaining;
size_t back = svc_len - front;
wpabuf_put_data(tmp_buf, adv->svc_name, front);
p2p_buf_update_ie_hdr(tmp_buf, tag_len);
tag_len = p2p_buf_add_ie_hdr(tmp_buf);
/* In rare cases, we must split across 3 attributes */
if (back > 255 - 4) {
wpabuf_put_data(tmp_buf,
&adv->svc_name[front], 255 - 4);
back -= 255 - 4;
front += 255 - 4;
p2p_buf_update_ie_hdr(tmp_buf, tag_len);
tag_len = p2p_buf_add_ie_hdr(tmp_buf);
}
wpabuf_put_data(tmp_buf, &adv->svc_name[front], back);
remaining = 255 - 4 - back;
} else {
wpabuf_put_data(tmp_buf, adv->svc_name, svc_len);
remaining -= svc_len;
}
/* adv_id config_methods svc_string */
total_len += sizeof(u32) + sizeof(u16) + sizeof(u8) + svc_len;
}
if (tag_len)
p2p_buf_update_ie_hdr(tmp_buf, tag_len);
if (ie_len)
WPA_PUT_LE16(ie_len, (u16) total_len);
wild_hash:
/* If all fit, return matching instances, otherwise the wildcard */
if (total_len <= MAX_SVC_ADV_LEN) {
wpabuf_put_buf(buf, tmp_buf);
} else {
char *wild_card = P2PS_WILD_HASH_STR;
u8 wild_len;
/* Insert wildcard instance */
tag_len = p2p_buf_add_ie_hdr(buf);
wpabuf_put_u8(buf, P2P_ATTR_ADVERTISED_SERVICE);
ie_len = wpabuf_put(buf, sizeof(u16));
wild_len = (u8) os_strlen(wild_card);
wpabuf_put_le32(buf, 0);
wpabuf_put_be16(buf, 0);
wpabuf_put_u8(buf, wild_len);
wpabuf_put_data(buf, wild_card, wild_len);
WPA_PUT_LE16(ie_len, 4 + 2 + 1 + wild_len);
p2p_buf_update_ie_hdr(buf, tag_len);
}
wpabuf_free(tmp_buf);
}
void p2p_buf_add_session_id(struct wpabuf *buf, u32 id, const u8 *mac)
{
if (!buf || !mac)

10
src/p2p/p2p_i.h
View file

@ -16,6 +16,13 @@
enum p2p_role_indication;
/*
* To force Service Instances to fit within a single P2P Tag, MAX_SVC_ADV_LEN
* must equal 248 or less. Must have a minimum size of 19.
*/
#define MAX_SVC_ADV_LEN 600
#define MAX_SVC_ADV_IE_LEN (9 + MAX_SVC_ADV_LEN + (5 * (MAX_SVC_ADV_LEN / 240)))
enum p2p_go_state {
UNKNOWN_GO,
LOCAL_GO,
@ -736,6 +743,9 @@ void p2p_buf_add_service_hash(struct wpabuf *buf, struct p2p_data *p2p);
void p2p_buf_add_session_info(struct wpabuf *buf, const char *info);
void p2p_buf_add_connection_capability(struct wpabuf *buf, u8 connection_cap);
void p2p_buf_add_advertisement_id(struct wpabuf *buf, u32 id, const u8 *mac);
void p2p_buf_add_service_instance(struct wpabuf *buf, struct p2p_data *p2p,
u8 count, const u8 *hash,
struct p2ps_advertisement *adv_list);
void p2p_buf_add_session_id(struct wpabuf *buf, u32 id, const u8 *mac);
void p2p_buf_add_feature_capability(struct wpabuf *buf, u16 len,
const u8 *mask);