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#include "query.h"
#include "benc.h"
#include "log.h"
#include <string.h>
#include <errno.h>
#include <assert.h>
int handle_request(struct nodeid* self, const char* method, const char* packet, size_t packet_len, char** response, size_t response_len) {
if(strcmp(method, "ping") == 0) {
struct bcursor bcursor;
struct benc_node stream[256];
bcur_open(&bcursor, packet, packet+packet_len, stream, 256);
if(bcursor.readhead->type != BNT_DICT) {
err("Bad query: Packet is not a dict");
return QUERY_EBADQ;
}
if(bcur_next(&bcursor, 1) < 0) {
err("Bad query: No token after outer dict start");
return QUERY_EBADQ;
}
if(bcur_find_key(&bcursor, (const enum benc_nodetype[]){BNT_STRING}, (const char*[]){"a"}, (const size_t[]){1}, 1) != 0) {
err("Bad query: No arguments to request");
return QUERY_EBADQ;
}
bcur_next(&bcursor, 1);
if(bcursor.readhead->type != BNT_DICT) {
err("Bad query: Wrong value type for request");
return QUERY_EBADQ;
}
// Skip the dict element
bcur_next(&bcursor, 1);
bool source_set = false;
struct nodeid source_id;
while(bcursor.readhead->type != BNT_END) {
switch(bcur_find_key(&bcursor, (const enum benc_nodetype[]){BNT_STRING}, (const char*[]){"id"}, (const size_t[]){6}, 1)) {
case 0:
// Skip the key
bcur_next(&bcursor, 1);
if(bcursor.readhead->type != BNT_STRING) {
err("Bad query: Wrong value type for id");
return QUERY_EBADQ;
}
if(bcursor.readhead->size != 20) {
err("Bad query: Incorrect id length");
return QUERY_EBADQ;
}
source_set = true;
memcpy(&source_id, bcursor.readhead->loc, 20);
// Skip the value
bcur_next(&bcursor, 1);
break;
}
}
if(!source_set) {
err("Id argument not set");
return QUERY_EBADQ;
}
char* end = (*response) + response_len;
int rc = snprintf(*response, end-*response, "d2:id20:");
if(rc < 0)
return QUERY_EBADQ;
*response += rc;
memcpy(*response, self, sizeof(struct nodeid));
*response += sizeof(struct nodeid);
rc = snprintf(*response, end-*response, "e");
if(rc < 0)
return QUERY_EBADQ;
*response += rc;
} else if(strcmp(method, "find_node") == 0) {
struct bcursor bcursor;
struct benc_node stream[256];
bcur_open(&bcursor, packet, packet+packet_len, stream, 256);
if(bcursor.readhead->type != BNT_DICT) {
err("Bad query: Packet is not a dict");
return QUERY_EBADQ;
}
if(bcur_next(&bcursor, 1) < 0) {
err("Bad query: No token after outer dict start");
return QUERY_EBADQ;
}
if(bcur_find_key(&bcursor, (const enum benc_nodetype[]){BNT_STRING}, (const char*[]){"a"}, (const size_t[]){1}, 1) != 0) {
err("Bad query: No arguments to request");
return QUERY_EBADQ;
}
bcur_next(&bcursor, 1);
if(bcursor.readhead->type != BNT_DICT) {
err("Bad query: Wrong value type for request");
return QUERY_EBADQ;
}
// Skip the dict element
bcur_next(&bcursor, 1);
bool target_set = false;
struct nodeid target;
while(bcursor.readhead->type != BNT_END) {
switch(bcur_find_key(&bcursor, (const enum benc_nodetype[]){BNT_STRING}, (const char*[]){"target"}, (const size_t[]){6}, 1)) {
case 0:
// Skip the key
bcur_next(&bcursor, 1);
if(bcursor.readhead->type != BNT_STRING) {
err("Bad query: Wrong value type for id");
return QUERY_EBADQ;
}
if(bcursor.readhead->size != 20) {
err("Bad query: Incorrect target length");
return QUERY_EBADQ;
}
target_set = true;
memcpy(&target, bcursor.readhead->loc, 20);
// Skip the value
bcur_next(&bcursor, 1);
break;
}
}
if(!target_set) {
err("Target argument not set");
return QUERY_EBADQ;
}
// Actually do the handling
struct entry* closest[8];
int found = routing_closest(&target, 8, closest);
char* end = (*response) + response_len;
int rc = snprintf(*response, end-*response, "d2:id20:");
if(rc < 0)
return QUERY_EBADQ;
*response += rc;
assert(*response < end);
memcpy(*response, self, sizeof(struct nodeid));
*response += sizeof(struct nodeid);
assert(*response < end);
rc = snprintf(*response, end-*response, "5:nodes%d:", found*26);
if(rc < 0)
return QUERY_EBADQ;
*response += rc;
assert(*response < end);
for(int i = 0; i < found; i++) {
memcpy(*response, &closest[i]->id, sizeof(struct nodeid));
*response += sizeof(struct nodeid); // 20
assert(*response < end);
memcpy(*response, &closest[i]->addr.ip, sizeof(uint32_t));
*response += sizeof(uint32_t); // 4
assert(*response < end);
memcpy(*response, &closest[i]->addr.port, sizeof(uint16_t));
*response += sizeof(uint16_t); // 2
assert(*response < end);
}
rc = snprintf(*response, end-*response, "e");
if(rc < 0)
return QUERY_EBADQ;
*response += rc;
assert(*response < end);
} else if(strcmp(method, "get_peers") == 0) {
} else {
return QUERY_EUNK;
}
return 0;
}
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