diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/user/app/ethdump/arp.c | 56 | ||||
| -rw-r--r-- | src/user/app/ethdump/ethdump.c | 207 | ||||
| -rw-r--r-- | src/user/app/ethdump/ether.c | 62 | ||||
| -rw-r--r-- | src/user/app/ethdump/icmp.c | 8 | ||||
| -rw-r--r-- | src/user/app/ethdump/ipv4.c | 50 | ||||
| -rw-r--r-- | src/user/app/ethdump/proto.h | 31 | ||||
| -rw-r--r-- | src/user/app/ethdump/util.c | 33 | ||||
| -rw-r--r-- | src/user/app/ethdump/util.h | 38 |
8 files changed, 289 insertions, 196 deletions
diff --git a/src/user/app/ethdump/arp.c b/src/user/app/ethdump/arp.c new file mode 100644 index 0000000..a022b12 --- /dev/null +++ b/src/user/app/ethdump/arp.c @@ -0,0 +1,56 @@ +#include "proto.h" +#include "util.h" +#include <stdlib.h> +#include <string.h> + +enum { + HdrType = 0, + HdrTypeEther = 1, + ProtoType = 2, + HdrALen = 4, + ProtoALen = 5, + Operation = 6, + OpReq = 1, + OpReply = 2, +}; + +void arp_parse(const uint8_t *buf, size_t len) { + // TODO no bound checks + uint16_t htype = nget16(buf + HdrType); + uint16_t ptype = nget16(buf + ProtoType); + uint16_t op = nget16(buf + Operation); + + const char *ops = "bad operation"; + if (op == 1) ops = "request"; + if (op == 2) ops = "reply"; + + printf("ARP htype 0x%x, ptype 0x%x, %s\n", htype, ptype, ops); + + if (!(htype == HdrTypeEther && ptype == ET_IPv4)) return; + enum { /* only valid for this combination of header + proto */ + SrcMAC = 8, + SrcIP = 14, + DstMAC = 18, + DstIP = 24, + }; + + if (op == OpReq) { + uint32_t daddr = nget32(buf + DstIP); + printf("IPv4 request for %08x\n", daddr); + if (daddr == state.ip) { + uint8_t *pkt = ether_start(30, (struct ethernet){ + .dst = buf + SrcMAC, + .type = ET_ARP, + }); + nput16(pkt + HdrType, 1); + nput16(pkt + ProtoType, ET_IPv4); + pkt[HdrALen] = 6; + pkt[ProtoALen] = 4; + nput16(pkt + Operation, OpReply); + memcpy(pkt + SrcMAC, state.mac, 6); + nput32(pkt + SrcIP, state.ip); + memcpy(pkt + DstMAC, buf + SrcMAC, 10); /* sender's MAC and IP */ + ether_finish(pkt); + } + } +} diff --git a/src/user/app/ethdump/ethdump.c b/src/user/app/ethdump/ethdump.c index 8d5be34..4047962 100644 --- a/src/user/app/ethdump/ethdump.c +++ b/src/user/app/ethdump/ethdump.c @@ -1,206 +1,21 @@ +#include "proto.h" +#include "util.h" #include <camellia/syscalls.h> #include <stdbool.h> #include <stddef.h> -#include <stdio.h> #include <stdlib.h> #include <string.h> -#define eprintf(fmt, ...) fprintf(stderr, "ethdump: "fmt"\n" __VA_OPT__(,) __VA_ARGS__) - -handle_t eth_h; - -// TODO dynamically get mac -uint8_t my_mac[] = {0x52, 0x54, 0x00, 0xCA, 0x77, 0x1A}; -uint32_t my_ip = (192 << 24) + (168 << 16) + 11; - -static void hexdump(const void *vbuf, size_t len) { - const uint8_t *buf = vbuf; - for (size_t i = 0; i < len; i += 16) { - printf("%08x ", i); - - for (size_t j = i; j < i + 8 && j < len; j++) - printf("%02x ", buf[j]); - printf(" "); - for (size_t j = i + 8; j < i + 16 && j < len; j++) - printf("%02x ", buf[j]); - printf("\n"); - } -} - -static void nput16(void *vbuf, uint16_t n) { - uint8_t *b = vbuf; - b[0] = n >> 8; - b[1] = n >> 0; -} - -static void nput32(void *vbuf, uint32_t n) { - uint8_t *b = vbuf; - b[0] = n >> 24; - b[1] = n >> 16; - b[2] = n >> 8; - b[3] = n >> 0; -} - -static uint16_t nget16(const void *vbuf) { - const uint8_t *b = vbuf; - return (b[0] << 8) - | (b[1] << 0); -} - -static uint32_t nget32(const void *vbuf) { - const uint8_t *b = vbuf; - return (b[0] << 24) - | (b[1] << 16) - | (b[2] << 8) - | (b[3] << 0); -} - - -static void parse_icmp(const uint8_t *buf, size_t len) { - if (len < 4) return; - uint8_t type = buf[0]; - printf("ICMP type %u\n", type); -} - - -static void parse_ipv4(const uint8_t *buf, size_t len) { - uint8_t version, headerlen, proto; - uint16_t packetlen, id, fragoffset; - uint32_t dest, src; - - version = buf[0] >> 4; - if (version != 4) { - printf("bad IPv4 version %u\n", version); - return; - } - headerlen = (buf[0] & 0xf) * 4; - packetlen = nget16(buf + 2); - id = nget16(buf + 4); - proto = buf[9]; - src = nget32(buf + 12); - dest = nget32(buf + 16); - - // TODO checksum - // TODO fragmentation - - printf("headerlen %u, packetlen %u (real %u), id %u\n", headerlen, packetlen, len, id); - printf("from %x to %x\n", src, dest); - printf("id %u\n", id); - if (packetlen < headerlen) { - printf("headerlen too big\n"); - return; - } - switch (proto) { - case 1: - printf("proto %u - icmp\n", proto); - parse_icmp(buf + headerlen, packetlen - headerlen); - break; - default: - printf("proto %u - unknown\n", proto); - break; - } -} - -static void parse_arp(const uint8_t *buf, size_t len) { - // TODO no bound checks - uint16_t htype = nget16(buf + 0); - uint16_t ptype = nget16(buf + 2); - uint16_t op = nget16(buf + 6); - - const char *ops = "bad operation"; - if (op == 1) ops = "request"; - if (op == 2) ops = "reply"; - - printf("ARP htype 0x%x, ptype 0x%x, %s\n", htype, ptype, ops); - - if (!(htype == 1 && ptype == 0x800)) return; - /* IPv4 over Ethernet */ - - if (op != 1) return; - /* a request */ - - uint32_t daddr = nget32(buf + 24); - printf("IPv4 request for %08x\n", daddr); - - if (daddr == my_ip) {/* send a response */ - char res[64]; - memset(res, 0, 64); - /* Ethernet */ - memcpy(res + 0, buf + 8, 6); /* from ARP sender MAC */ - memcpy(res + 6, my_mac, 6); - nput16(res + 12, 0x0806); /* ethertype == ARP */ - - /* ARP */ - nput16(res + 14, 1); /* Ethernet */ - nput16(res + 16, 0x800); /* IPv4 */ - res[18] = 6; res[19] = 4; /* address lengths */ - nput16(res + 20, 2); /* operation == reply */ - memcpy(res + 22, my_mac, 6); - nput32(res + 28, my_ip); - memcpy(res + 32, buf + 8, 10); /* sender's MAC and IP */ - printf("sending ARP response:\n"); - hexdump(res, sizeof res); - _syscall_write(eth_h, res, sizeof res, 0, 0); - } -} - -/* https://www.w3.org/TR/PNG/#D-CRCAppendix */ -uint32_t crc_table[256]; -static uint32_t crc32(const uint8_t *buf, size_t len) { - if (!crc_table[1]) { - for (int i = 0; i < 256; i++) { - uint32_t c = i; - for (int j = 0; j < 8; j++) - c = ((c&1) ? 0xedb88320 : 0) ^ (c >> 1); - crc_table[i] = c; - } - } - - uint32_t c = 0xFFFFFFFF; - for (size_t i = 0; i < len; i++) - c = crc_table[(c ^ buf[i]) & 0xff] ^ (c >> 8); - return ~c; -} - -static void parse_ethernet(const uint8_t *buf, size_t len) { - uint8_t dmac[6], smac[6]; - - if (len < 60) return; - for (int i = 0; i < 6; i++) dmac[i] = buf[i]; - for (int i = 0; i < 6; i++) smac[i] = buf[i + 6]; - printf("from %02x:%02x:%02x:%02x:%02x:%02x\n", - smac[0], smac[1], smac[2], smac[3], smac[4], smac[5]); - printf("to %02x:%02x:%02x:%02x:%02x:%02x\n", - dmac[0], dmac[1], dmac[2], dmac[3], dmac[4], dmac[5]); - - if (false) { - /* byte order switched on purpose */ - uint32_t crc = (buf[len - 1] << 24) - | (buf[len - 2] << 16) - | (buf[len - 3] << 8) - | (buf[len - 4] << 0); - printf("fcf %x, crc %x\n", crc, crc32(buf, len - 4)); - } - - uint16_t ethertype = nget16(buf + 12); - printf("ethertype %u\n", ethertype); - switch (ethertype) { - case 0x800: - parse_ipv4(buf + 14, len - 14); - break; - case 0x806: - parse_arp(buf + 14, len - 14); - break; - default: - printf("(unknown)\n"); - break; - } -} +struct net_state state = { + // TODO dynamically get mac + .mac = {0x52, 0x54, 0x00, 0xCA, 0x77, 0x1A}, + .ip = (192 << 24) + (168 << 16) + 11, +}; int main(void) { const char *path = "/kdev/eth"; - eth_h = _syscall_open(path, strlen(path), 0); - if (eth_h < 0) { + state.raw_h = _syscall_open(path, strlen(path), 0); + if (state.raw_h < 0) { eprintf("couldn't open %s", path); return 1; } @@ -208,11 +23,11 @@ int main(void) { const size_t buflen = 4096; char *buf = malloc(buflen); for (;;) { - long ret = _syscall_read(eth_h, buf, buflen, -1); + long ret = _syscall_read(state.raw_h, buf, buflen, -1); if (ret < 0) break; printf("\npacket of length %u\n", ret); hexdump(buf, ret); - parse_ethernet((void*)buf, ret); + ether_parse((void*)buf, ret); } free(buf); return 0; diff --git a/src/user/app/ethdump/ether.c b/src/user/app/ethdump/ether.c new file mode 100644 index 0000000..da21b49 --- /dev/null +++ b/src/user/app/ethdump/ether.c @@ -0,0 +1,62 @@ +#include <camellia/syscalls.h> +#include <stdlib.h> +#include <string.h> +#include "proto.h" +#include "util.h" + +enum { + DstMAC = 0, + SrcMAC = 6, + EtherType = 12, + Payload = 14, +}; + +void ether_parse(const uint8_t *buf, size_t len) { + uint8_t dmac[6], smac[6]; + + if (len < 60) return; + for (int i = 0; i < 6; i++) dmac[i] = buf[i + DstMAC]; + for (int i = 0; i < 6; i++) smac[i] = buf[i + SrcMAC]; + printf("from %02x:%02x:%02x:%02x:%02x:%02x\n", + smac[0], smac[1], smac[2], smac[3], smac[4], smac[5]); + printf("to %02x:%02x:%02x:%02x:%02x:%02x\n", + dmac[0], dmac[1], dmac[2], dmac[3], dmac[4], dmac[5]); + + uint16_t ethertype = nget16(buf + EtherType); + printf("ethertype %u\n", ethertype); + switch (ethertype) { + case ET_IPv4: + ipv4_parse(buf + Payload, len - Payload); + break; + case ET_ARP: + arp_parse(buf + Payload, len - Payload); + break; + default: + printf("(unknown)\n"); + break; + } +} + +static const size_t fhoff = sizeof(size_t); +uint8_t *ether_start(size_t len, struct ethernet ether) { + if (len < 60 - Payload) len = 60 - Payload; + + if (!ether.dst) eprintf("NULL ether.dst!"); // TODO arp? i guess? + if (!ether.src) ether.src = &state.mac; + + uint8_t *buf = malloc(fhoff + Payload + len); + memset(buf, 0, fhoff + Payload + len); + *(size_t*)buf = len + Payload; + memcpy(buf + fhoff + DstMAC, ether.dst, 6); + memcpy(buf + fhoff + SrcMAC, ether.src, 6); + nput16(buf + fhoff + EtherType, ether.type); + return buf + fhoff + Payload; +} +void ether_finish(uint8_t *pkt) { + uint8_t *buf = pkt - Payload - fhoff; + size_t len = *(size_t*)buf; + printf("sending:\n"); + hexdump(buf + fhoff, len); + _syscall_write(state.raw_h, buf + fhoff, len, 0, 0); + free(buf); +} diff --git a/src/user/app/ethdump/icmp.c b/src/user/app/ethdump/icmp.c new file mode 100644 index 0000000..9c80a2d --- /dev/null +++ b/src/user/app/ethdump/icmp.c @@ -0,0 +1,8 @@ +#include "proto.h" +#include "util.h" + +void icmp_parse(const uint8_t *buf, size_t len) { + if (len < 4) return; + uint8_t type = buf[0]; + printf("ICMP type %u\n", type); +} diff --git a/src/user/app/ethdump/ipv4.c b/src/user/app/ethdump/ipv4.c new file mode 100644 index 0000000..408e1df --- /dev/null +++ b/src/user/app/ethdump/ipv4.c @@ -0,0 +1,50 @@ +#include "proto.h" +#include "util.h" + +enum { + Version = 0, + HdrLen = 0, + PktLen = 2, + Id = 4, + Proto = 9, + SrcIP = 12, + DestIP = 16, +}; + +void ipv4_parse(const uint8_t *buf, size_t len) { + uint8_t version, headerlen, proto; + uint16_t packetlen, id; + uint32_t dest, src; + + version = buf[Version] >> 4; + if (version != 4) { + printf("bad IPv4 version %u\n", version); + return; + } + headerlen = (buf[HdrLen] & 0xf) * 4; + packetlen = nget16(buf + PktLen); + id = nget16(buf + Id); + proto = buf[Proto]; + src = nget32(buf + SrcIP); + dest = nget32(buf + DestIP); + + // TODO checksum + // TODO fragmentation + + printf("headerlen %u, packetlen %u (real %u), id %u\n", headerlen, packetlen, len, id); + printf("from %x to %x\n", src, dest); + printf("id %u\n", id); + if (packetlen < headerlen) { + printf("headerlen too big\n"); + return; + } + switch (proto) { + case 1: + printf("proto %u - icmp\n", proto); + icmp_parse(buf + headerlen, packetlen - headerlen); + break; + default: + printf("proto %u - unknown\n", proto); + break; + } +} diff --git a/src/user/app/ethdump/proto.h b/src/user/app/ethdump/proto.h new file mode 100644 index 0000000..f47ca53 --- /dev/null +++ b/src/user/app/ethdump/proto.h @@ -0,0 +1,31 @@ +#pragma once +#include <camellia/types.h> +#include <stdint.h> + +typedef uint8_t mac_t[6]; + +extern struct net_state { + mac_t mac; + uint32_t ip; + + handle_t raw_h; +} state; + +enum { /* ethertype */ + ET_IPv4 = 0x800, + ET_ARP = 0x806, +}; + +struct ethernet { + const mac_t *src, *dst; + uint16_t type; +}; + + +void arp_parse(const uint8_t *buf, size_t len); +void icmp_parse(const uint8_t *buf, size_t len); +void ipv4_parse(const uint8_t *buf, size_t len); + +void ether_parse(const uint8_t *buf, size_t len); +uint8_t *ether_start(size_t len, struct ethernet ether); +void ether_finish(uint8_t *pkt); diff --git a/src/user/app/ethdump/util.c b/src/user/app/ethdump/util.c new file mode 100644 index 0000000..b0d8785 --- /dev/null +++ b/src/user/app/ethdump/util.c @@ -0,0 +1,33 @@ +#include "util.h" + +void hexdump(const void *vbuf, size_t len) { + const uint8_t *buf = vbuf; + for (size_t i = 0; i < len; i += 16) { + printf("%08x ", i); + + for (size_t j = i; j < i + 8 && j < len; j++) + printf("%02x ", buf[j]); + printf(" "); + for (size_t j = i + 8; j < i + 16 && j < len; j++) + printf("%02x ", buf[j]); + printf("\n"); + } +} + +/* https://www.w3.org/TR/PNG/#D-CRCAppendix */ +static uint32_t crc_table[256]; +uint32_t crc32(const uint8_t *buf, size_t len) { + if (!crc_table[1]) { + for (int i = 0; i < 256; i++) { + uint32_t c = i; + for (int j = 0; j < 8; j++) + c = ((c&1) ? 0xedb88320 : 0) ^ (c >> 1); + crc_table[i] = c; + } + } + + uint32_t c = 0xFFFFFFFF; + for (size_t i = 0; i < len; i++) + c = crc_table[(c ^ buf[i]) & 0xff] ^ (c >> 8); + return ~c; +} diff --git a/src/user/app/ethdump/util.h b/src/user/app/ethdump/util.h new file mode 100644 index 0000000..536f270 --- /dev/null +++ b/src/user/app/ethdump/util.h @@ -0,0 +1,38 @@ +#pragma once +#include <stdint.h> +#include <stdio.h> + +#define eprintf(fmt, ...) fprintf(stderr, "ethdump: "fmt"\n" __VA_OPT__(,) __VA_ARGS__) + +void hexdump(const void *vbuf, size_t len); + +uint32_t crc32(const uint8_t *buf, size_t len); + + +static inline void nput16(void *vbuf, uint16_t n) { + uint8_t *b = vbuf; + b[0] = n >> 8; + b[1] = n >> 0; +} + +static inline void nput32(void *vbuf, uint32_t n) { + uint8_t *b = vbuf; + b[0] = n >> 24; + b[1] = n >> 16; + b[2] = n >> 8; + b[3] = n >> 0; +} + +static inline uint16_t nget16(const void *vbuf) { + const uint8_t *b = vbuf; + return (b[0] << 8) + | (b[1] << 0); +} + +static inline uint32_t nget32(const void *vbuf) { + const uint8_t *b = vbuf; + return (b[0] << 24) + | (b[1] << 16) + | (b[2] << 8) + | (b[3] << 0); +} |