/* Copyright Joyent, Inc. and other Node contributors.

*

* Permission is hereby granted, free of charge, to any person obtaining a

* copy of this software and associated documentation files (the

* "Software"), to deal in the Software without restriction, including

* without limitation the rights to use, copy, modify, merge, publish,

* distribute, sublicense, and/or sell copies of the Software, and to permit

* persons to whom the Software is furnished to do so, subject to the

* following conditions:

*

* The above copyright notice and this permission notice shall be included

* in all copies or substantial portions of the Software.

*

* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS

* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF

* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN

* NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,

* DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR

* OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE

* USE OR OTHER DEALINGS IN THE SOFTWARE.

*/

/*

* This is the DTrace library file for the node provider, which includes

* the necessary translators to get from the args[] to something useful.

* Be warned: the mechanics here are seriously ugly -- and one must always

* keep in mind that clean abstractions often require filthy systems.

*/

#pragma D depends_on library procfs.d

typedef struct {

int32_t fd;

int32_t port;

uint32_t remote;

uint32_t buffered;

} node_dtrace_connection_t;

typedef struct {

int32_t fd;

int32_t port;

uint64_t remote;

uint32_t buffered;

} node_dtrace_connection64_t;

typedef struct {

int fd;

string remoteAddress;

int remotePort;

int bufferSize;

} node_connection_t;

translator node_connection_t <node_dtrace_connection_t *nc> {

fd = *(int32_t *)copyin((uintptr_t)&nc->fd, sizeof (int32_t));

remotePort =

*(int32_t *)copyin((uintptr_t)&nc->port, sizeof (int32_t));

remoteAddress = curpsinfo->pr_dmodel == PR_MODEL_ILP32 ?

copyinstr((uintptr_t)*(uint32_t *)copyin((uintptr_t)&nc->remote,

sizeof (int32_t))) :

copyinstr((uintptr_t)*(uint64_t *)copyin((uintptr_t)

&((node_dtrace_connection64_t *)nc)->remote, sizeof (int64_t)));

bufferSize = curpsinfo->pr_dmodel == PR_MODEL_ILP32 ?

*(uint32_t *)copyin((uintptr_t)&nc->buffered, sizeof (int32_t)) :

*(uint32_t *)copyin((uintptr_t)

&((node_dtrace_connection64_t *)nc)->buffered, sizeof (int32_t));

};

/*

* 32-bit and 64-bit structures received from node for HTTP client request

* probe.

*/

typedef struct {

uint32_t url;

uint32_t method;

} node_dtrace_http_client_request_t;

typedef struct {

uint64_t url;

uint64_t method;

} node_dtrace_http_client_request64_t;

/*

* The following structures are never used directly, but must exist to bind the

* types specified in the provider to the translators defined here.

* Ultimately, they always get cast to a more specific type inside the

* translator. To add to the confusion, the DTrace compiler does not allow

* declaring two translators with the same destination type if the source types

* are structures with the same size (because libctf says they're compatible,

* so dtrace considers them equivalent). Since we must define translators from

* node_dtrace_http_client_request_t (above), node_dtrace_http_request_t, and

* node_dtrace_http_server_request_t (both below), each of these three structs

* must be declared with a different size.

*/

typedef struct {

uint32_t version;

uint64_t dummy1;

} node_dtrace_http_request_t;

typedef struct {

uint32_t version;

uint64_t dummy2;

uint64_t dummy3;

} node_dtrace_http_server_request_t;

/*

* Actual 32-bit and 64-bit, v0 and v1 structures received from node for the

* HTTP server request probe.

*/

typedef struct {

uint32_t url;

uint32_t method;

} node_dtrace_http_server_request_v0_t;

typedef struct {

uint32_t version;

uint32_t url;

uint32_t method;

uint32_t forwardedFor;

} node_dtrace_http_server_request_v1_t;

typedef struct {

uint64_t url;

uint64_t method;

} node_dtrace_http_server_request64_v0_t;

typedef struct {

uint32_t version;

uint32_t pad;

uint64_t url;

uint64_t method;

uint64_t forwardedFor;

} node_dtrace_http_server_request64_v1_t;

/*

* In the end, both client and server request probes from both old and new

* binaries translate their arguments to node_http_request_t, which is what the

* user's D script ultimately sees.

*/

typedef struct {

string url;

string method;

string forwardedFor;

} node_http_request_t;

/*

* The following translators are particularly filthy for reasons of backwards

* compatibility. Stable versions of node prior to 0.6 used a single

* http_request struct with fields for "url" and "method" for both client and

* server probes. 0.6 added a "forwardedFor" field intended for the server

* probe only, and the http_request struct passed by the application was split

* first into client_http_request and server_http_request and the latter was

* again split for v0 (the old struct) and v1.

*

* To distinguish the binary representations of the two versions of these

* structs, the new version prepends a "version" member (where the old one has

* a "url" pointer). Each field that we're translating below first switches on

* the value of this "version" field: if it's larger than 4096, we know we must

* be looking at the "url" pointer of the older structure version. Otherwise,

* we must be looking at the new version. Besides this, we have the usual

* switch based on the userland process data model. This would all be simpler

* with macros, but those aren't available in D library files since we cannot

* rely on cpp being present at runtime.

*

* In retrospect, the versioning bit might have been unnecessary since the type

* of the object passed in should allow DTrace to select which translator to

* use. However, DTrace does sometimes use translators whose source types

* don't quite match, and since we know this versioning logic works, we just

* leave it alone. Each of the translators below is functionally identical

* (except that the client -> client translator doesn't bother translating

* forwardedFor) and should actually work with any version of any of the client

* or server structs transmitted by the application up to this point.

*/

/*

* Translate from node_dtrace_http_server_request_t (received from node 0.6 and

* later versions) to node_http_request_t.

*/

translator node_http_request_t <node_dtrace_http_server_request_t *nd> {

url = (*(uint32_t *)copyin((uintptr_t)(uint32_t *)nd,

sizeof (uint32_t))) >= 4096 ?

(curpsinfo->pr_dmodel == PR_MODEL_ILP32 ?

copyinstr(*(uint32_t *)copyin((uintptr_t)

&((node_dtrace_http_server_request_v0_t *)nd)->url,

sizeof (uint32_t))) :

copyinstr(*(uint64_t *)copyin((uintptr_t)

&((node_dtrace_http_server_request64_v0_t *)nd)->url,

sizeof (uint64_t)))) :

(curpsinfo->pr_dmodel == PR_MODEL_ILP32 ?

copyinstr(*(uint32_t *)copyin((uintptr_t)

&((node_dtrace_http_server_request_v1_t *)nd)->url,

sizeof (uint32_t))) :

copyinstr(*(uint64_t *)copyin((uintptr_t)

&((node_dtrace_http_server_request64_v1_t *)nd)->url,

sizeof (uint64_t))));

method = (*(uint32_t *)copyin((uintptr_t)(uint32_t *)nd,

sizeof (uint32_t))) >= 4096 ?

(curpsinfo->pr_dmodel == PR_MODEL_ILP32 ?

copyinstr(*(uint32_t *)copyin((uintptr_t)

&((node_dtrace_http_server_request_v0_t *)nd)->method,

sizeof (uint32_t))) :

copyinstr(*(uint64_t *)copyin((uintptr_t)

&((node_dtrace_http_server_request64_v0_t *)nd)->method,

sizeof (uint64_t)))) :

(curpsinfo->pr_dmodel == PR_MODEL_ILP32 ?

copyinstr(*(uint32_t *)copyin((uintptr_t)

&((node_dtrace_http_server_request_v1_t *)nd)->method,

sizeof (uint32_t))) :

copyinstr(*(uint64_t *)copyin((uintptr_t)

&((node_dtrace_http_server_request64_v1_t *)nd)->method,

sizeof (uint64_t))));

forwardedFor = (*(uint32_t *)copyin((uintptr_t)(uint32_t *)nd,

sizeof (uint32_t))) >= 4096 ? "" :

(curpsinfo->pr_dmodel == PR_MODEL_ILP32 ?

copyinstr(*(uint32_t *)copyin((uintptr_t)

&((node_dtrace_http_server_request_v1_t *)nd)->forwardedFor,

sizeof (uint32_t))) :

copyinstr(*(uint64_t *)copyin((uintptr_t)

&((node_dtrace_http_server_request64_v1_t *)nd)->

forwardedFor, sizeof (uint64_t))));

};

/*

* Translate from node_dtrace_http_client_request_t (received from node 0.6 and

* later versions) to node_http_request_t.

*/

translator node_http_request_t <node_dtrace_http_client_request_t *nd> {

url = (*(uint32_t *)copyin((uintptr_t)(uint32_t *)nd,

sizeof (uint32_t))) >= 4096 ?

(curpsinfo->pr_dmodel == PR_MODEL_ILP32 ?

copyinstr(*(uint32_t *)copyin((uintptr_t)

&((node_dtrace_http_server_request_v0_t *)nd)->url,

sizeof (uint32_t))) :

copyinstr(*(uint64_t *)copyin((uintptr_t)

&((node_dtrace_http_server_request64_v0_t *)nd)->url,

sizeof (uint64_t)))) :

(curpsinfo->pr_dmodel == PR_MODEL_ILP32 ?

copyinstr(*(uint32_t *)copyin((uintptr_t)

&((node_dtrace_http_server_request_v1_t *)nd)->url,

sizeof (uint32_t))) :

copyinstr(*(uint64_t *)copyin((uintptr_t)

&((node_dtrace_http_server_request64_v1_t *)nd)->url,

sizeof (uint64_t))));

method = (*(uint32_t *)copyin((uintptr_t)(uint32_t *)nd,

sizeof (uint32_t))) >= 4096 ?

(curpsinfo->pr_dmodel == PR_MODEL_ILP32 ?

copyinstr(*(uint32_t *)copyin((uintptr_t)

&((node_dtrace_http_server_request_v0_t *)nd)->method,

sizeof (uint32_t))) :

copyinstr(*(uint64_t *)copyin((uintptr_t)

&((node_dtrace_http_server_request64_v0_t *)nd)->method,

sizeof (uint64_t)))) :

(curpsinfo->pr_dmodel == PR_MODEL_ILP32 ?

copyinstr(*(uint32_t *)copyin((uintptr_t)

&((node_dtrace_http_server_request_v1_t *)nd)->method,

sizeof (uint32_t))) :

copyinstr(*(uint64_t *)copyin((uintptr_t)

&((node_dtrace_http_server_request64_v1_t *)nd)->method,

sizeof (uint64_t))));

forwardedFor = "";

};

/*

* Translate from node_dtrace_http_request_t (received from versions of node

* prior to 0.6) to node_http_request_t. This is used for both the server and

* client probes since these versions of node didn't distinguish between the

* types used in these probes.

*/

translator node_http_request_t <node_dtrace_http_request_t *nd> {

url = (*(uint32_t *)copyin((uintptr_t)(uint32_t *)nd,

sizeof (uint32_t))) >= 4096 ?

(curpsinfo->pr_dmodel == PR_MODEL_ILP32 ?

copyinstr(*(uint32_t *)copyin((uintptr_t)

&((node_dtrace_http_server_request_v0_t *)nd)->url,

sizeof (uint32_t))) :

copyinstr(*(uint64_t *)copyin((uintptr_t)

&((node_dtrace_http_server_request64_v0_t *)nd)->url,

sizeof (uint64_t)))) :

(curpsinfo->pr_dmodel == PR_MODEL_ILP32 ?

copyinstr(*(uint32_t *)copyin((uintptr_t)

&((node_dtrace_http_server_request_v1_t *)nd)->url,

sizeof (uint32_t))) :

copyinstr(*(uint64_t *)copyin((uintptr_t)

&((node_dtrace_http_server_request64_v1_t *)nd)->url,

sizeof (uint64_t))));

method = (*(uint32_t *)copyin((uintptr_t)(uint32_t *)nd,

sizeof (uint32_t))) >= 4096 ?

(curpsinfo->pr_dmodel == PR_MODEL_ILP32 ?

copyinstr(*(uint32_t *)copyin((uintptr_t)

&((node_dtrace_http_server_request_v0_t *)nd)->method,

sizeof (uint32_t))) :

copyinstr(*(uint64_t *)copyin((uintptr_t)

&((node_dtrace_http_server_request64_v0_t *)nd)->method,

sizeof (uint64_t)))) :

(curpsinfo->pr_dmodel == PR_MODEL_ILP32 ?

copyinstr(*(uint32_t *)copyin((uintptr_t)

&((node_dtrace_http_server_request_v1_t *)nd)->method,

sizeof (uint32_t))) :

copyinstr(*(uint64_t *)copyin((uintptr_t)

&((node_dtrace_http_server_request64_v1_t *)nd)->method,

sizeof (uint64_t))));

forwardedFor = (*(uint32_t *) copyin((uintptr_t)(uint32_t *)nd,

sizeof (uint32_t))) >= 4096 ? "" :

(curpsinfo->pr_dmodel == PR_MODEL_ILP32 ?

copyinstr(*(uint32_t *)copyin((uintptr_t)

&((node_dtrace_http_server_request_v1_t *)nd)->forwardedFor,

sizeof (uint32_t))) :

copyinstr(*(uint64_t *)copyin((uintptr_t)

&((node_dtrace_http_server_request64_v1_t *)nd)->

forwardedFor, sizeof (uint64_t))));

};