PyObject *
Interest_obj_from_ccn(PyObject *py_interest)
{
struct ccn_charbuf *interest;
struct ccn_parsed_interest *pi;
PyObject *py_obj_Interest, *py_o;
int r;
debug("Interest_from_ccn_parsed start\n");
interest = CCNObject_Get(INTEREST, py_interest);
// 1) Create python object
py_obj_Interest = PyObject_CallObject(g_type_Interest, NULL);
if (!py_obj_Interest)
return NULL;
pi = _pyccn_interest_get_pi(py_interest);
JUMP_IF_NULL(pi, error);
// 2) Set ccn_data to a cobject pointing to the c struct
// and ensure proper destructor is set up for the c object.
r = PyObject_SetAttrString(py_obj_Interest, "ccn_data", py_interest);
JUMP_IF_NEG(r, error);
// 3) Parse c structure and fill python attributes
// using PyObject_SetAttrString
ssize_t len;
const unsigned char *blob;
size_t blob_size, start, end;
struct ccn_charbuf * cb;
// Best decoding examples are in packet-ccn.c for wireshark plugin?
// self.name = None # Start from None to use for templates?
len = pi->offset[CCN_PI_E_Name] - pi->offset[CCN_PI_B_Name];
if (len > 0) {
PyObject *py_cname;
py_cname = CCNObject_New_charbuf(NAME, &cb);
JUMP_IF_NULL(py_cname, error);
r = ccn_charbuf_append(cb, interest->buf + pi->offset[CCN_PI_B_Name],
len);
JUMP_IF_NEG_MEM(r, error);
py_o = Name_obj_from_ccn(py_cname);
Py_DECREF(py_cname);
JUMP_IF_NULL(py_o, error);
r = PyObject_SetAttrString(py_obj_Interest, "name", py_o);
Py_DECREF(py_o);
JUMP_IF_NEG(r, error);
} else {
PyErr_SetString(g_PyExc_CCNInterestError, "Got interest without a"
" name!");
goto error;
}
// self.minSuffixComponents = None # default 0
len = pi->offset[CCN_PI_E_MinSuffixComponents] -
pi->offset[CCN_PI_B_MinSuffixComponents];
if (len > 0) {
r = ccn_fetch_tagged_nonNegativeInteger(CCN_DTAG_MinSuffixComponents,
interest->buf, pi->offset[CCN_PI_B_MinSuffixComponents],
pi->offset[CCN_PI_E_MinSuffixComponents]);
if (r < 0) {
PyErr_SetString(g_PyExc_CCNInterestError, "Invalid"
" MinSuffixComponents value");
goto error;
}
py_o = _pyccn_Int_FromLong(r);
JUMP_IF_NULL(py_o, error);
r = PyObject_SetAttrString(py_obj_Interest, "minSuffixComponents",
py_o);
Py_DECREF(py_o);
JUMP_IF_NEG(r, error);
}
// self.maxSuffixComponents = None # default infinity
len = pi->offset[CCN_PI_E_MaxSuffixComponents] -
pi->offset[CCN_PI_B_MaxSuffixComponents];
if (len > 0) {
r = ccn_fetch_tagged_nonNegativeInteger(CCN_DTAG_MaxSuffixComponents,
interest->buf, pi->offset[CCN_PI_B_MaxSuffixComponents],
pi->offset[CCN_PI_E_MaxSuffixComponents]);
if (r < 0) {
PyErr_SetString(g_PyExc_CCNInterestError, "Invalid"
" MaxSuffixComponents value");
goto error;
}
py_o = _pyccn_Int_FromLong(r);
JUMP_IF_NULL(py_o, error);
r = PyObject_SetAttrString(py_obj_Interest, "maxSuffixComponents",
py_o);
Py_DECREF(py_o);
JUMP_IF_NEG(r, error);
}
// self.publisherPublicKeyDigest = None # SHA256 hash
// TODO: what is CN_PI_B_PublisherID? -- looks like it is the data including
// the tags while PublisherIDKeyDigest
// is just the raw digest -- dk
start = pi->offset[CCN_PI_B_PublisherID];
end = pi->offset[CCN_PI_E_PublisherID];
len = end - start;
if (len > 0) {
r = ccn_ref_tagged_BLOB(CCN_DTAG_PublisherPublicKeyDigest,
interest->buf, start, end, &blob, &blob_size);
if (r < 0) {
PyErr_SetString(g_PyExc_CCNInterestError, "Invalid"
" PublisherPublicKeyDigest value");
goto error;
}
py_o = PyBytes_FromStringAndSize((const char*) blob, blob_size);
JUMP_IF_NULL(py_o, error);
r = PyObject_SetAttrString(py_obj_Interest, "publisherPublicKeyDigest",
py_o);
Py_DECREF(py_o);
JUMP_IF_NEG(r, error);
}
// self.exclude = None
len = pi->offset[CCN_PI_E_Exclude] - pi->offset[CCN_PI_B_Exclude];
if (len > 0) {
PyObject *py_exclusion_filter;
py_exclusion_filter = CCNObject_New_charbuf(EXCLUSION_FILTER, &cb);
JUMP_IF_NULL(py_exclusion_filter, error);
r = ccn_charbuf_append(cb, interest->buf + pi->offset[CCN_PI_B_Exclude],
len);
JUMP_IF_NEG_MEM(r, error);
py_o = ExclusionFilter_obj_from_ccn(py_exclusion_filter);
Py_DECREF(py_exclusion_filter);
JUMP_IF_NULL(py_o, error);
r = PyObject_SetAttrString(py_obj_Interest, "exclude", py_o);
Py_DECREF(py_o);
JUMP_IF_NEG(r, error);
}
// self.childSelector = None
len = pi->offset[CCN_PI_E_ChildSelector] -
pi->offset[CCN_PI_B_ChildSelector];
if (len > 0) {
r = ccn_fetch_tagged_nonNegativeInteger(CCN_DTAG_ChildSelector,
interest->buf, pi->offset[CCN_PI_B_ChildSelector],
pi->offset[CCN_PI_E_ChildSelector]);
if (r < 0) {
PyErr_SetString(g_PyExc_CCNInterestError, "Invalid"
" ChildSelector value");
goto error;
}
py_o = _pyccn_Int_FromLong(r);
JUMP_IF_NULL(py_o, error);
r = PyObject_SetAttrString(py_obj_Interest, "childSelector", py_o);
Py_DECREF(py_o);
JUMP_IF_NEG(r, error);
}
// self.answerOriginKind = None
len = pi->offset[CCN_PI_E_AnswerOriginKind] -
pi->offset[CCN_PI_B_AnswerOriginKind];
if (len > 0) {
r = ccn_fetch_tagged_nonNegativeInteger(CCN_DTAG_AnswerOriginKind,
interest->buf, pi->offset[CCN_PI_B_AnswerOriginKind],
pi->offset[CCN_PI_E_AnswerOriginKind]);
if (r < 0) {
PyErr_SetString(g_PyExc_CCNInterestError, "Invalid"
" AnswerOriginKind value");
goto error;
}
py_o = _pyccn_Int_FromLong(r);
JUMP_IF_NULL(py_o, error);
r = PyObject_SetAttrString(py_obj_Interest, "answerOriginKind", py_o);
Py_DECREF(py_o);
JUMP_IF_NEG(r, error);
}
// self.scope = None
len = pi->offset[CCN_PI_E_Scope] - pi->offset[CCN_PI_B_Scope];
if (len > 0) {
r = ccn_fetch_tagged_nonNegativeInteger(CCN_DTAG_Scope, interest->buf,
pi->offset[CCN_PI_B_Scope], pi->offset[CCN_PI_E_Scope]);
if (r < 0) {
PyErr_SetString(g_PyExc_CCNInterestError, "Invalid"
" Scope value");
goto error;
}
py_o = _pyccn_Int_FromLong(r);
JUMP_IF_NULL(py_o, error);
r = PyObject_SetAttrString(py_obj_Interest, "scope", py_o);
Py_DECREF(py_o);
JUMP_IF_NEG(r, error);
}
// self.interestLifetime = None
len = pi->offset[CCN_PI_E_InterestLifetime] -
pi->offset[CCN_PI_B_InterestLifetime];
if (len > 0) {
double lifetime;
// From packet-ccn.c
r = ccn_ref_tagged_BLOB(CCN_DTAG_InterestLifetime, interest->buf,
pi->offset[CCN_PI_B_InterestLifetime],
pi->offset[CCN_PI_E_InterestLifetime], &blob, &blob_size);
if (r < 0) {
PyErr_SetString(g_PyExc_CCNInterestError, "Invalid"
" InterestLifetime value");
goto error;
}
/* XXX: probably won't work with bigendian */
lifetime = 0.0;
for (size_t i = 0; i < blob_size; i++)
lifetime = lifetime * 256.0 + (double) blob[i];
lifetime /= 4096.0;
py_o = PyFloat_FromDouble(lifetime);
JUMP_IF_NULL(py_o, error);
r = PyObject_SetAttrString(py_obj_Interest, "interestLifetime", py_o);
Py_DECREF(py_o);
JUMP_IF_NEG(r, error);
}
// self.nonce = None
len = pi->offset[CCN_PI_E_Nonce] - pi->offset[CCN_PI_B_Nonce];
if (len > 0) {
r = ccn_ref_tagged_BLOB(CCN_DTAG_Nonce, interest->buf,
pi->offset[CCN_PI_B_Nonce], pi->offset[CCN_PI_E_Nonce], &blob,
&blob_size);
if (r < 0) {
PyErr_SetString(g_PyExc_CCNInterestError, "Invalid"
" Nonce value");
goto error;
}
py_o = PyBytes_FromStringAndSize((const char *) blob, blob_size);
JUMP_IF_NULL(py_o, error);
r = PyObject_SetAttrString(py_obj_Interest, "nonce", py_o);
Py_DECREF(py_o);
JUMP_IF_NEG(r, error);
}
r = PyObject_SetAttrString(py_obj_Interest, "ccn_data_dirty", Py_False);
JUMP_IF_NEG(r, error);
// 4) Return the created object
debug("Interest_from_ccn ends\n");
return py_obj_Interest;
error:
Py_DECREF(py_obj_Interest);
return NULL;
}
static int
dissect_ccn_contentobject(const unsigned char *ccnb, size_t ccnb_size, tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
proto_tree *signature_tree;
proto_tree *name_tree;
proto_tree *signedinfo_tree;
proto_tree *content_tree;
proto_item *titem;
struct ccn_parsed_ContentObject co;
struct ccn_parsed_ContentObject *pco = &co;
struct ccn_charbuf *c;
struct ccn_indexbuf *comps;
const unsigned char *comp;
size_t comp_size;
size_t blob_size;
const unsigned char *blob;
int l;
unsigned int i;
double dt;
nstime_t timestamp;
int res;
comps = ccn_indexbuf_create();
res = ccn_parse_ContentObject(ccnb, ccnb_size, pco, comps);
if (res < 0) return (-1);
/* Signature */
l = pco->offset[CCN_PCO_E_Signature] - pco->offset[CCN_PCO_B_Signature];
titem = proto_tree_add_item(tree, hf_ccn_signature, tvb, pco->offset[CCN_PCO_B_Signature], l, FALSE);
signature_tree = proto_item_add_subtree(titem, ett_signature);
/* DigestAlgorithm */
l = pco->offset[CCN_PCO_E_DigestAlgorithm] - pco->offset[CCN_PCO_B_DigestAlgorithm];
if (l > 0) {
res = ccn_ref_tagged_BLOB(CCN_DTAG_DigestAlgorithm, ccnb,
pco->offset[CCN_PCO_B_DigestAlgorithm],
pco->offset[CCN_PCO_E_DigestAlgorithm],
&blob, &blob_size);
titem = proto_tree_add_item(signature_tree, hf_ccn_signaturedigestalg, tvb,
blob - ccnb, blob_size, FALSE);
}
/* Witness */
l = pco->offset[CCN_PCO_E_Witness] - pco->offset[CCN_PCO_B_Witness];
if (l > 0) {
/* add the witness item to the signature tree */
}
/* Signature bits */
l = pco->offset[CCN_PCO_E_SignatureBits] - pco->offset[CCN_PCO_B_SignatureBits];
if (l > 0) {
res = ccn_ref_tagged_BLOB(CCN_DTAG_SignatureBits, ccnb,
pco->offset[CCN_PCO_B_SignatureBits],
pco->offset[CCN_PCO_E_SignatureBits],
&blob, &blob_size);
titem = proto_tree_add_bytes(signature_tree, hf_ccn_signaturebits, tvb,
blob - ccnb, blob_size, blob);
}
/* /Signature */
/* Name */
l = pco->offset[CCN_PCO_E_Name] - pco->offset[CCN_PCO_B_Name];
c = ccn_charbuf_create();
ccn_uri_append(c, ccnb, ccnb_size, 1);
titem = proto_tree_add_string(tree, hf_ccn_name, tvb,
pco->offset[CCN_PCO_B_Name], l,
ccn_charbuf_as_string(c));
name_tree = proto_item_add_subtree(titem, ett_name);
ccn_charbuf_destroy(&c);
/* Name Components */
for (i = 0; i < comps->n - 1; i++) {
res = ccn_name_comp_get(ccnb, comps, i, &comp, &comp_size);
titem = proto_tree_add_item(name_tree, hf_ccn_name_components, tvb, comp - ccnb, comp_size, FALSE);
}
/* /Name */
/* SignedInfo */
l = pco->offset[CCN_PCO_E_SignedInfo] - pco->offset[CCN_PCO_B_SignedInfo];
titem = proto_tree_add_text(tree, tvb,
pco->offset[CCN_PCO_B_SignedInfo], l,
"SignedInfo");
signedinfo_tree = proto_item_add_subtree(titem, ett_signedinfo);
/* PublisherPublicKeyDigest */
l = pco->offset[CCN_PCO_E_PublisherPublicKeyDigest] - pco->offset[CCN_PCO_B_PublisherPublicKeyDigest];
if (l > 0) {
res = ccn_ref_tagged_BLOB(CCN_DTAG_PublisherPublicKeyDigest, ccnb,
pco->offset[CCN_PCO_B_PublisherPublicKeyDigest],
pco->offset[CCN_PCO_E_PublisherPublicKeyDigest],
&blob, &blob_size);
titem = proto_tree_add_bytes(signedinfo_tree, hf_ccn_publisherpublickeydigest, tvb, blob - ccnb, blob_size, blob);
}
/* Timestamp */
l = pco->offset[CCN_PCO_E_Timestamp] - pco->offset[CCN_PCO_B_Timestamp];
if (l > 0) {
res = ccn_ref_tagged_BLOB(CCN_DTAG_Timestamp, ccnb,
pco->offset[CCN_PCO_B_Timestamp],
pco->offset[CCN_PCO_E_Timestamp],
&blob, &blob_size);
dt = 0.0;
for (i = 0; i < blob_size; i++)
dt = dt * 256.0 + (double)blob[i];
dt /= 4096.0;
timestamp.secs = dt; /* truncates */
timestamp.nsecs = (dt - (double) timestamp.secs) * 1000000000.0;
titem = proto_tree_add_time(signedinfo_tree, hf_ccn_timestamp, tvb, blob - ccnb, blob_size, ×tamp);
}
/* Type */
l = pco->offset[CCN_PCO_E_Type] - pco->offset[CCN_PCO_B_Type];
if (l > 0) {
res = ccn_ref_tagged_BLOB(CCN_DTAG_Type, ccnb,
pco->offset[CCN_PCO_B_Type],
pco->offset[CCN_PCO_E_Type],
&blob, &blob_size);
titem = proto_tree_add_int(signedinfo_tree, hf_ccn_contenttype, tvb, blob - ccnb, blob_size, pco->type);
} else {
titem = proto_tree_add_int(signedinfo_tree, hf_ccn_contenttype, NULL, 0, 0, pco->type);
}
/* FreshnessSeconds */
l = pco->offset[CCN_PCO_E_FreshnessSeconds] - pco->offset[CCN_PCO_B_FreshnessSeconds];
if (l > 0) {
res = ccn_ref_tagged_BLOB(CCN_DTAG_FreshnessSeconds, ccnb,
pco->offset[CCN_PCO_B_FreshnessSeconds],
pco->offset[CCN_PCO_E_FreshnessSeconds],
&blob, &blob_size);
i = ccn_fetch_tagged_nonNegativeInteger(CCN_DTAG_FreshnessSeconds, ccnb,
pco->offset[CCN_PCO_B_FreshnessSeconds],
pco->offset[CCN_PCO_E_FreshnessSeconds]);
titem = proto_tree_add_uint(signedinfo_tree, hf_ccn_freshnessseconds, tvb, blob - ccnb, blob_size, i);
}
/* FinalBlockID */
l = pco->offset[CCN_PCO_E_FinalBlockID] - pco->offset[CCN_PCO_B_FinalBlockID];
if (l > 0) {
res = ccn_ref_tagged_BLOB(CCN_DTAG_FinalBlockID, ccnb,
pco->offset[CCN_PCO_B_FinalBlockID],
pco->offset[CCN_PCO_E_FinalBlockID],
&blob, &blob_size);
titem = proto_tree_add_item(signedinfo_tree, hf_ccn_finalblockid, tvb, blob - ccnb, blob_size, FALSE);
}
/* TODO: KeyLocator */
/* /SignedInfo */
/* Content */
l = pco->offset[CCN_PCO_E_Content] - pco->offset[CCN_PCO_B_Content];
res = ccn_ref_tagged_BLOB(CCN_DTAG_Content, ccnb,
pco->offset[CCN_PCO_B_Content],
pco->offset[CCN_PCO_E_Content],
&blob, &blob_size);
titem = proto_tree_add_text(tree, tvb,
pco->offset[CCN_PCO_B_Content], l,
"Content: %d bytes", blob_size);
if (blob_size > 0) {
content_tree = proto_item_add_subtree(titem, ett_content);
titem = proto_tree_add_item(content_tree, hf_ccn_contentdata, tvb, blob - ccnb, blob_size, FALSE);
}
return (ccnb_size);
}
PUBLIC struct content_entry *
r_store_lookup(struct ccnr_handle *h,
const unsigned char *msg,
const struct ccn_parsed_interest *pi,
struct ccn_indexbuf *comps)
{
struct content_entry *content = NULL;
struct ccn_btree_node *leaf = NULL;
ccnr_cookie last_match = 0;
ccnr_accession last_match_acc = CCNR_NULL_ACCESSION;
struct ccn_charbuf *scratch = NULL;
size_t size = pi->offset[CCN_PI_E];
int ndx;
int res;
int try;
content = r_store_find_first_match_candidate(h, msg, pi);
if (content != NULL && CCNSHOULDLOG(h, LM_8, CCNL_FINER))
ccnr_debug_content(h, __LINE__, "first_candidate", NULL,
content);
if (content != NULL &&
!r_store_content_matches_interest_prefix(h, content, msg, size)) {
if (CCNSHOULDLOG(h, LM_8, CCNL_FINER))
ccnr_debug_ccnb(h, __LINE__, "prefix_mismatch", NULL,
msg, size);
content = NULL;
}
scratch = ccn_charbuf_create();
for (try = 0; content != NULL; try++) {
res = ccn_btree_lookup(h->btree,
content->flatname->buf,
content->flatname->length,
&leaf);
if (CCN_BT_SRCH_FOUND(res) == 0) {
ccnr_debug_content(h, __LINE__, "impossible", NULL, content);
content = NULL;
break;
}
ndx = CCN_BT_SRCH_INDEX(res);
res = ccn_btree_match_interest(leaf, ndx, msg, pi, scratch);
if (res == -1) {
ccnr_debug_ccnb(h, __LINE__, "match_error", NULL, msg, size);
content = NULL;
break;
}
if (res == 1) {
if ((pi->orderpref & 1) == 0) // XXX - should be symbolic
break;
last_match = content->cookie;
last_match_acc = content->accession;
content = r_store_next_child_at_level(h, content, comps->n - 1);
}
else
content = r_store_content_next(h, content);
if (content != NULL &&
!r_store_content_matches_interest_prefix(h, content, msg, size))
content = NULL;
}
if (last_match != 0) {
content = r_store_content_from_cookie(h, last_match);
if (content == NULL)
content = r_store_content_from_accession(h, last_match_acc);
}
ccn_charbuf_destroy(&scratch);
return(content);
}
/**
* Find the first content handle that matches the prefix given by the namish,
* which may be a Name, Interest, ContentObject, ...
*
* Does not check the other parts of namish, in particular, does not generate
* the digest component of a ContentObject.
*/
PUBLIC struct content_entry *
r_store_lookup_ccnb(struct ccnr_handle *h,
const unsigned char *namish, size_t size)
{
struct content_entry *content = NULL;
struct ccn_charbuf *flatname = NULL;
int res;
flatname = ccn_charbuf_create();
if (flatname == NULL)
goto Bail;
res = ccn_flatname_from_ccnb(flatname, namish, size);
if (res < 0)
goto Bail;
content = r_store_look(h, flatname->buf, flatname->length);
if (content != NULL) {
res = ccn_flatname_charbuf_compare(flatname, content->flatname);
if (res == 0 || res == -9999) {
/* prefix matches */
}
else
content = NULL;
}
Bail:
ccn_charbuf_destroy(&flatname);
return(content);
}
/**
* Mark content as stale
*/
PUBLIC void
r_store_mark_stale(struct ccnr_handle *h, struct content_entry *content)
{
ccnr_cookie cookie = content->cookie;
if ((content->flags & CCN_CONTENT_ENTRY_STALE) != 0)
return;
if (CCNSHOULDLOG(h, LM_4, CCNL_FINE))
ccnr_debug_content(h, __LINE__, "stale", NULL, content);
content->flags |= CCN_CONTENT_ENTRY_STALE;
h->n_stale++;
if (cookie < h->min_stale)
h->min_stale = cookie;
if (cookie > h->max_stale)
h->max_stale = cookie;
}
/**
* Scheduled event that makes content stale when its FreshnessSeconds
* has expired.
*/
static int
expire_content(struct ccn_schedule *sched,
void *clienth,
struct ccn_scheduled_event *ev,
int flags)
{
struct ccnr_handle *h = clienth;
ccnr_cookie cookie = ev->evint;
struct content_entry *content = NULL;
if ((flags & CCN_SCHEDULE_CANCEL) != 0)
return(0);
content = r_store_content_from_cookie(h, cookie);
if (content != NULL)
r_store_mark_stale(h, content);
return(0);
}
/**
* Schedules content expiration based on its FreshnessSeconds.
*
*/
PUBLIC void
r_store_set_content_timer(struct ccnr_handle *h, struct content_entry *content,
struct ccn_parsed_ContentObject *pco)
{
int seconds = 0;
int microseconds = 0;
size_t start = pco->offset[CCN_PCO_B_FreshnessSeconds];
size_t stop = pco->offset[CCN_PCO_E_FreshnessSeconds];
const unsigned char *content_msg = NULL;
if (start == stop)
return;
content_msg = r_store_content_base(h, content);
seconds = ccn_fetch_tagged_nonNegativeInteger(
CCN_DTAG_FreshnessSeconds,
content_msg,
start, stop);
if (seconds <= 0)
return;
if (seconds > ((1U<<31) / 1000000)) {
ccnr_debug_content(h, __LINE__, "FreshnessSeconds_too_large", NULL,
content);
return;
}
microseconds = seconds * 1000000;
ccn_schedule_event(h->sched, microseconds,
&expire_content, NULL, content->cookie);
}
