1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
|
/* Copyright (C) 2022 CZ.NIC, z.s.p.o. <knot-dns@labs.nic.cz>
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <https://www.gnu.org/licenses/>.
*/
#include <assert.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "load_queries.h"
#include "libknot/libknot.h"
#include "utils/common/msg.h"
#define ERR_PREFIX "failed loading queries "
enum qflags {
QFLAG_EDNS = 1,
QFLAG_DO = 2,
};
struct pkt_payload *global_payloads = NULL;
void free_global_payloads()
{
struct pkt_payload *g_payloads_p = global_payloads, *tmp;
while (g_payloads_p != NULL) {
tmp = g_payloads_p;
g_payloads_p = tmp->next;
free(tmp);
}
global_payloads = NULL;
}
bool load_queries(const char *filename, uint16_t edns_size, uint16_t msgid)
{
FILE *f = fopen(filename, "r");
if (f == NULL) {
ERR2(ERR_PREFIX "file '%s' (%s)", filename, strerror(errno));
return false;
}
struct pkt_payload *g_payloads_top = NULL;
struct {
char line[KNOT_DNAME_TXT_MAXLEN + 256];
char dname_txt[KNOT_DNAME_TXT_MAXLEN + 1];
uint8_t dname[KNOT_DNAME_MAXLEN];
char type_txt[128];
char flags_txt[128];
} *bufs;
bufs = malloc(sizeof(*bufs)); // avoiding too much stuff on stack
if (bufs == NULL) {
ERR2(ERR_PREFIX "(out of memory)");
goto fail;
}
while (fgets(bufs->line, sizeof(bufs->line), f) != NULL) {
bufs->flags_txt[0] = '\0';
int ret = sscanf(bufs->line, "%s%s%s", bufs->dname_txt, bufs->type_txt, bufs->flags_txt);
if (ret < 2) {
ERR2(ERR_PREFIX "(faulty line): '%.*s'",
(int)strcspn(bufs->line, "\n"), bufs->line);
goto fail;
}
void *pret = knot_dname_from_str(bufs->dname, bufs->dname_txt, sizeof(bufs->dname));
if (pret == NULL) {
ERR2(ERR_PREFIX "(faulty dname): '%s'", bufs->dname_txt);
goto fail;
}
uint16_t type;
ret = knot_rrtype_from_string(bufs->type_txt, &type);
if (ret < 0) {
ERR2(ERR_PREFIX "(faulty type): '%s'", bufs->type_txt);
goto fail;
}
enum qflags flags = 0;
switch (bufs->flags_txt[0]) {
case '\0':
break;
case 'e':
case 'E':
flags |= QFLAG_EDNS;
break;
case 'd':
case 'D':
flags |= QFLAG_EDNS | QFLAG_DO;
break;
default:
ERR2(ERR_PREFIX "(faulty flag): '%s'", bufs->flags_txt);
goto fail;
}
size_t dname_len = knot_dname_size(bufs->dname);
size_t pkt_len = KNOT_WIRE_HEADER_SIZE + 2 * sizeof(uint16_t) + dname_len;
if (flags & QFLAG_EDNS) {
pkt_len += KNOT_EDNS_MIN_SIZE;
}
struct pkt_payload *pkt = calloc(1, sizeof(struct pkt_payload) + pkt_len);
if (pkt == NULL) {
ERR2(ERR_PREFIX "(out of memory)");
goto fail;
}
pkt->len = pkt_len;
memcpy(pkt->payload, &msgid, sizeof(msgid));
pkt->payload[2] = 0x01; // QR bit
pkt->payload[5] = 0x01; // 1 question
pkt->payload[11] = (flags & QFLAG_EDNS) ? 0x01 : 0x00;
memcpy(pkt->payload + 12, bufs->dname, dname_len);
pkt->payload[dname_len + 12] = type >> 8;
pkt->payload[dname_len + 13] = type & 0xff;
pkt->payload[dname_len + 15] = KNOT_CLASS_IN;
if (flags & QFLAG_EDNS) {
pkt->payload[dname_len + 18] = KNOT_RRTYPE_OPT;
pkt->payload[dname_len + 19] = edns_size >> 8;
pkt->payload[dname_len + 20] = edns_size & 0xff;
pkt->payload[dname_len + 23] = (flags & QFLAG_DO) ? 0x80 : 0x00;
}
// add pkt to list global_payloads
if (g_payloads_top == NULL) {
global_payloads = pkt;
g_payloads_top = pkt;
} else {
g_payloads_top->next = pkt;
g_payloads_top = pkt;
}
}
if (global_payloads == NULL) {
ERR2(ERR_PREFIX "(no queries in file)");
goto fail;
}
free(bufs);
fclose(f);
return true;
fail:
free_global_payloads();
free(bufs);
fclose(f);
return false;
}
|
