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sfan5sfan5
committed
Some code refactoring
1 parent 75d3f4d commit f52ab7b

3 files changed

Lines changed: 63 additions & 52 deletions

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‎src/rawsock.h‎

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -56,7 +56,7 @@ struct pseudo_header {
5656
uint8_t ipproto;
5757
} __attribute__((packed));
5858

59-
typedef void (*rawsock_callback)(uint64_t /* timestamp */, int /* length */, const uint8_t* /* packet */);
59+
typedef void (*rawsock_callback)(uint64_t /* timestamp */, unsigned int /* length */, const uint8_t* /* packet */);
6060

6161
int rawsock_open(const char *dev, int buffersize);
6262
int rawsock_has_ethernet_headers(void);

‎src/scan-reader.c‎

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -14,7 +14,7 @@
1414
#include "banner.h" // banner_postprocess
1515
#include "rawsock.h" // IP_TYPE_{TCP,UDP}
1616

17-
static int show_closed, banners;
17+
static bool show_closed, banners;
1818
//
1919
static FILE *outfile;
2020
static struct outputdef outdef;

‎src/scan.c‎

Lines changed: 61 additions & 50 deletions
Original file line numberDiff line numberDiff line change
@@ -23,6 +23,25 @@
2323
#include "icmp.h"
2424
#include "banner.h"
2525

26+
// for convenience
27+
#ifndef u_int
28+
typedef unsigned int u_int;
29+
#endif
30+
31+
#if __has_builtin(__builtin_expect)
32+
// "unlikely"
33+
#define unl(expr) __builtin_expect((expr), 0)
34+
#else
35+
#define unl(expr) expr
36+
#endif
37+
38+
enum {
39+
FULL_TCP_SIZE = FRAME_ETH_SIZE + FRAME_IP_SIZE + TCP_HEADER_SIZE,
40+
FULL_UDP_SIZE = FRAME_ETH_SIZE + FRAME_IP_SIZE + UDP_HEADER_SIZE,
41+
FULL_ICMP_SIZE = FRAME_ETH_SIZE + FRAME_IP_SIZE + ICMP_HEADER_SIZE,
42+
};
43+
44+
// status_bits:
2645
enum {
2746
SEND_FINISHED = (1 << 0),
2847
ERROR_SEND_THREAD = (1 << 1),
@@ -33,8 +52,8 @@ static uint8_t source_addr[16];
3352
static int source_port;
3453
//
3554
static struct ports ports;
36-
static unsigned int max_rate;
37-
static int show_closed, banners;
55+
static u_int max_rate;
56+
static bool show_closed, banners;
3857
static uint8_t ip_type;
3958
//
4059
static FILE *outfile;
@@ -50,17 +69,17 @@ static void *send_thread_udp(void *unused);
5069
static void *send_thread_icmp(void *unused);
5170

5271
static void *recv_thread(void *unused);
53-
static void recv_handler(uint64_t ts, int len, const uint8_t *packet);
54-
static void recv_handler_tcp(uint64_t ts, int len, const uint8_t *packet, const uint8_t *csrcaddr);
55-
static void recv_handler_udp(uint64_t ts, int len, const uint8_t *packet, const uint8_t *csrcaddr);
56-
static void recv_handler_icmp(uint64_t ts, int len, const uint8_t *packet, const uint8_t *csrcaddr);
72+
static void recv_handler(uint64_t ts, u_int len, const uint8_t *packet);
73+
static void recv_handler_tcp(uint64_t ts, u_int len, const uint8_t *packet, const uint8_t *csrcaddr);
74+
static void recv_handler_udp(uint64_t ts, u_int len, const uint8_t *packet, const uint8_t *csrcaddr);
75+
static void recv_handler_icmp(uint64_t ts, u_int len, const uint8_t *packet, const uint8_t *csrcaddr);
5776

5877
#if ATOMIC_INT_LOCK_FREE != 2
59-
#warning Non lock-free atomic types will severely affect performance.
78+
#warning Non lock-free atomic types will probably reduce performance.
6079
#endif
6180

6281
#define RATE_CONTROL() do { \
63-
if(atomic_fetch_add(&pkts_sent, 1) >= max_rate) { \
82+
if(unl(atomic_fetch_add(&pkts_sent, 1) >= max_rate)) { \
6483
do usleep(1000); while(atomic_load(&pkts_sent) != 0); \
6584
} \
6685
} while(0)
@@ -70,7 +89,7 @@ static void recv_handler_icmp(uint64_t ts, int len, const uint8_t *packet, const
7089
void scan_set_general(const struct ports *_ports, int _max_rate, int _show_closed, int _banners)
7190
{
7291
memcpy(&ports, _ports, sizeof(struct ports));
73-
max_rate = _max_rate < 0 ? UINT_MAX : _max_rate - 1;
92+
max_rate = _max_rate <= 0 ? UINT_MAX : (_max_rate - 1);
7493
show_closed = _show_closed;
7594
banners = _banners;
7695
}
@@ -139,13 +158,13 @@ int scan_main(const char *interface, int quiet)
139158
// Stats & progress watching
140159
unsigned char cur_status = 0;
141160
while(1) {
142-
unsigned int cur_sent, cur_recv;
161+
u_int cur_sent, cur_recv;
143162
// (used for rate control)
144163
cur_sent = atomic_exchange(&pkts_sent, 0);
145164
cur_recv = atomic_exchange(&pkts_recv, 0);
146165
if(!quiet) {
147166
float progress = target_gen_progress();
148-
unsigned int tcp_sent = 0;
167+
u_int tcp_sent = 0;
149168
char tmp[10] = {'?', '?', '?', 0};
150169
if(progress >= 0.0f)
151170
snprintf(tmp, sizeof(tmp), "%3d", (int) (progress*100));
@@ -178,8 +197,8 @@ int scan_main(const char *interface, int quiet)
178197
if(banners && ip_type == IP_TYPE_TCP)
179198
scan_responder_finish();
180199
if(!quiet && !cur_status) {
181-
unsigned int cur_recv = atomic_exchange(&pkts_recv, 0);
182-
unsigned int tcp_sent = 0;
200+
u_int cur_recv = atomic_exchange(&pkts_recv, 0);
201+
u_int tcp_sent = 0;
183202
if(banners && ip_type == IP_TYPE_TCP) {
184203
scan_responder_stats(&tcp_sent);
185204
fprintf(stderr, "rcv:%5u tcp:%5u\n", cur_recv, tcp_sent);
@@ -200,7 +219,7 @@ int scan_main(const char *interface, int quiet)
200219
goto ret;
201220
}
202221

203-
static bool calc_bps(char *dst, unsigned int dstsize, uint64_t m1, uint64_t m2)
222+
static bool calc_bps(char *dst, u_int dstsize, uint64_t m1, uint64_t m2)
204223
{
205224
uint64_t bps;
206225
#if __has_builtin(__builtin_mul_overflow)
@@ -222,31 +241,29 @@ static bool calc_bps(char *dst, unsigned int dstsize, uint64_t m1, uint64_t m2)
222241

223242
void scan_print_summary(const struct ports *ports, int max_rate, int banners, uint8_t ip_type)
224243
{
225-
unsigned int payload_min = 9999, payload_max = 0;
244+
u_int payload_min = 9999, payload_max = 0;
226245
if(ip_type == IP_TYPE_TCP) {
227-
payload_min = payload_max = TCP_HEADER_SIZE;
246+
payload_min = payload_max = FULL_TCP_SIZE;
228247
} else if(ip_type == IP_TYPE_UDP && !banners) {
229-
payload_min = payload_max = UDP_HEADER_SIZE;
248+
payload_min = payload_max = FULL_UDP_SIZE;
230249
} else if(ip_type == IP_TYPE_UDP) {
231250
// Need to know actual ports to know payload size
232251
if(!validate_ports(ports))
233252
return;
234253
struct ports_iter it;
235254
ports_iter_begin(ports, &it);
236255
while(ports_iter_next(&it) == 1) {
237-
unsigned int len = 0;
256+
u_int len = 0;
238257
banner_get_query(IP_TYPE_UDP, it.val, &len);
239-
len += UDP_HEADER_SIZE;
258+
len += FULL_UDP_SIZE;
240259
if(len < payload_min)
241260
payload_min = len;
242261
if(len > payload_max)
243262
payload_max = len;
244263
}
245264
} else if(ip_type == IP_TYPE_ICMPV6) {
246-
payload_min = payload_max = ICMP_HEADER_SIZE;
265+
payload_min = payload_max = FULL_ICMP_SIZE;
247266
}
248-
payload_min += FRAME_ETH_SIZE + FRAME_IP_SIZE;
249-
payload_max += FRAME_ETH_SIZE + FRAME_IP_SIZE;
250267

251268
if(payload_min == payload_max) {
252269
printf("Scanning will send packets with %u octets (incl. Ethernet and IP headers).\n",
@@ -273,7 +290,7 @@ void scan_print_summary(const struct ports *ports, int max_rate, int banners, ui
273290

274291
static void *send_thread_tcp(void *unused)
275292
{
276-
uint8_t _Alignas(uint32_t) packet[FRAME_ETH_SIZE + FRAME_IP_SIZE + TCP_HEADER_SIZE];
293+
uint8_t _Alignas(uint32_t) packet[FULL_TCP_SIZE];
277294
uint8_t dstaddr[16];
278295
struct ports_iter it;
279296

@@ -316,7 +333,7 @@ static void *send_thread_tcp(void *unused)
316333

317334
static void *send_thread_udp(void *unused)
318335
{
319-
uint8_t _Alignas(uint32_t) packet[FRAME_ETH_SIZE + FRAME_IP_SIZE + UDP_HEADER_SIZE + BANNER_QUERY_MAX_LENGTH];
336+
uint8_t _Alignas(uint32_t) packet[FULL_UDP_SIZE + BANNER_QUERY_MAX_LENGTH];
320337
uint8_t dstaddr[16];
321338
struct ports_iter it;
322339

@@ -347,7 +364,7 @@ static void *send_thread_udp(void *unused)
347364

348365
uint16_t dstport = it.val;
349366
udp_modify(UDP_HEADER(packet), source_port==-1?source_port_rand():source_port, dstport);
350-
unsigned int dlen = 0;
367+
u_int dlen = 0;
351368
if(banners) {
352369
const char *payload = banner_get_query(IP_TYPE_UDP, dstport, &dlen);
353370
if(payload && dlen > 0)
@@ -357,7 +374,7 @@ static void *send_thread_udp(void *unused)
357374
}
358375

359376
udp_checksum(IP_FRAME(packet), UDP_HEADER(packet), dlen);
360-
rawsock_send(packet, FRAME_ETH_SIZE + FRAME_IP_SIZE + UDP_HEADER_SIZE + dlen);
377+
rawsock_send(packet, FULL_UDP_SIZE + dlen);
361378

362379
RATE_CONTROL();
363380
}
@@ -371,7 +388,7 @@ static void *send_thread_udp(void *unused)
371388

372389
static void *send_thread_icmp(void *unused)
373390
{
374-
uint8_t _Alignas(uint32_t) packet[FRAME_ETH_SIZE + FRAME_IP_SIZE + ICMP_HEADER_SIZE];
391+
uint8_t _Alignas(uint32_t) packet[FULL_ICMP_SIZE];
375392
uint8_t dstaddr[16];
376393

377394
(void) unused;
@@ -420,24 +437,23 @@ static void *recv_thread(void *unused)
420437
return NULL;
421438
}
422439

423-
static void recv_handler(uint64_t ts, int len, const uint8_t *packet)
440+
static void recv_handler(uint64_t ts, u_int len, const uint8_t *packet)
424441
{
425442
int v;
426443
const uint8_t *csrcaddr;
427444

428445
atomic_fetch_add(&pkts_recv, 1);
429446

430-
// decode
431447
if(rawsock_has_ethernet_headers()) {
432-
if(len < FRAME_ETH_SIZE)
448+
if(unl(len < FRAME_ETH_SIZE))
433449
goto perr;
434450
rawsock_eth_decode(ETH_FRAME(packet), &v);
435451
} else {
436452
v = ETH_TYPE_IPV6;
437453
packet -= FRAME_ETH_SIZE; // FIXME: convenient but horrible hack
438454
len += FRAME_ETH_SIZE;
439455
}
440-
if(v != ETH_TYPE_IPV6 || len < FRAME_ETH_SIZE + FRAME_IP_SIZE)
456+
if(unl(v != ETH_TYPE_IPV6 || len < FRAME_ETH_SIZE + FRAME_IP_SIZE))
441457
goto perr;
442458
rawsock_ip_decode(IP_FRAME(packet), &v, NULL, NULL, &csrcaddr, NULL);
443459

@@ -458,11 +474,11 @@ static void recv_handler(uint64_t ts, int len, const uint8_t *packet)
458474
#endif
459475
}
460476

461-
static void recv_handler_tcp(uint64_t ts, int len, const uint8_t *packet, const uint8_t *csrcaddr)
477+
static void recv_handler_tcp(uint64_t ts, u_int len, const uint8_t *packet, const uint8_t *csrcaddr)
462478
{
463-
if(ip_type != IP_TYPE_TCP)
479+
if(unl(ip_type != IP_TYPE_TCP))
464480
goto perr;
465-
if(len < FRAME_ETH_SIZE + FRAME_IP_SIZE + TCP_HEADER_SIZE)
481+
if(unl(len < FULL_TCP_SIZE))
466482
goto perr;
467483

468484
// Output stuff
@@ -485,11 +501,11 @@ static void recv_handler_tcp(uint64_t ts, int len, const uint8_t *packet, const
485501
#endif
486502
}
487503

488-
static void recv_handler_udp(uint64_t ts, int len, const uint8_t *packet, const uint8_t *csrcaddr)
504+
static void recv_handler_udp(uint64_t ts, u_int len, const uint8_t *packet, const uint8_t *csrcaddr)
489505
{
490-
if(ip_type != IP_TYPE_UDP)
506+
if(unl(ip_type != IP_TYPE_UDP))
491507
goto perr;
492-
if(len < FRAME_ETH_SIZE + FRAME_IP_SIZE + UDP_HEADER_SIZE)
508+
if(unl(len < FULL_UDP_SIZE))
493509
goto perr;
494510

495511
int v;
@@ -502,7 +518,7 @@ static void recv_handler_udp(uint64_t ts, int len, const uint8_t *packet, const
502518
return;
503519
}
504520

505-
uint32_t plen = len - (FRAME_ETH_SIZE + FRAME_IP_SIZE + UDP_HEADER_SIZE);
521+
uint32_t plen = len - FULL_UDP_SIZE;
506522
if(plen == 0)
507523
return;
508524
else if(plen > BANNER_MAX_LENGTH)
@@ -520,20 +536,16 @@ static void recv_handler_udp(uint64_t ts, int len, const uint8_t *packet, const
520536
#endif
521537
}
522538

523-
enum {
524-
FULL_ICMP_SIZE = FRAME_ETH_SIZE + FRAME_IP_SIZE + ICMP_HEADER_SIZE,
525-
};
526-
527539
#define INNER_IP_FRAME(buf) ( (const struct frame_ip*) &(buf)[FULL_ICMP_SIZE] )
528540
#define INNER_UDP_HEADER(buf) ( (const struct udp_header*) &(buf)[FULL_ICMP_SIZE + FRAME_IP_SIZE] )
529541

530-
static void handle_icmp_error(uint64_t ts, int len, const uint8_t *packet, const uint8_t *csrcaddr)
542+
static void handle_icmp_error(uint64_t ts, u_int len, const uint8_t *packet, const uint8_t *csrcaddr)
531543
{
532544
// (detection of closed UDP ports only so far)
533-
if(ip_type != IP_TYPE_UDP)
545+
if(unl(ip_type != IP_TYPE_UDP))
534546
goto perr;
535-
const int minlen = FULL_ICMP_SIZE + FRAME_IP_SIZE + UDP_HEADER_SIZE;
536-
if(len < minlen)
547+
const u_int minlen = FULL_ICMP_SIZE + FRAME_IP_SIZE + UDP_HEADER_SIZE;
548+
if(unl(len < minlen))
537549
goto perr;
538550

539551
// Note: the destination ip/port and protocol type are already checked
@@ -570,17 +582,16 @@ static void handle_icmp_error(uint64_t ts, int len, const uint8_t *packet, const
570582
#undef INNER_IP_FRAME
571583
#undef INNER_UDP_HEADER
572584

573-
static void recv_handler_icmp(uint64_t ts, int len, const uint8_t *packet, const uint8_t *csrcaddr)
585+
static void recv_handler_icmp(uint64_t ts, u_int len, const uint8_t *packet, const uint8_t *csrcaddr)
574586
{
575-
const int minlen = FRAME_ETH_SIZE + FRAME_IP_SIZE + ICMP_HEADER_SIZE;
576-
if(len < minlen)
587+
if(unl(len < FULL_ICMP_SIZE))
577588
goto perr;
578589

579590
if(ICMP_HEADER(packet)->type < 128)
580591
return handle_icmp_error(ts, len, packet, csrcaddr);
581592

582593
// handling for icmp echo scans follows:
583-
if(len != minlen)
594+
if(len != FULL_ICMP_SIZE)
584595
return;
585596
if(ICMP_HEADER(packet)->type != 129) // Echo Reply
586597
return;

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