diff options
| -rw-r--r-- | .gitignore | 2 | ||||
| -rw-r--r-- | Makefile | 8 | ||||
| -rw-r--r-- | ethersend.c | 118 |
3 files changed, 128 insertions, 0 deletions
diff --git a/.gitignore b/.gitignore new file mode 100644 index 0000000..07e611d --- /dev/null +++ b/.gitignore @@ -0,0 +1,2 @@ +*~ +/ethersend diff --git a/Makefile b/Makefile new file mode 100644 index 0000000..08a9322 --- /dev/null +++ b/Makefile @@ -0,0 +1,8 @@ +CFLAGS = -Wall + +all: ethersend + +clean: + rm -f ethersend + +.PHONY: clean diff --git a/ethersend.c b/ethersend.c new file mode 100644 index 0000000..f210401 --- /dev/null +++ b/ethersend.c @@ -0,0 +1,118 @@ +/* + Copyright (c) 2013, Matthias Schiffer <mschiffer@universe-factory.net> + All rights reserved. + + Redistribution and use in source and binary forms, with or without + modification, are permitted provided that the following conditions are met: + + 1. Redistributions of source code must retain the above copyright notice, + this list of conditions and the following disclaimer. + 2. Redistributions in binary form must reproduce the above copyright notice, + this list of conditions and the following disclaimer in the documentation + and/or other materials provided with the distribution. + + THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" + AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE + DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE + FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR + SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER + CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, + OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. +*/ + + +#include <stdint.h> +#include <stdio.h> +#include <string.h> +#include <unistd.h> + +#include <arpa/inet.h> + +#include <linux/if_ether.h> + +#include <net/if.h> + +#include <netpacket/packet.h> + +#include <sys/socket.h> +#include <sys/types.h> + + +static void usage(const char *name) { + fprintf(stderr, "Usage: %s interface dest ethertype\n", name); +} + +int main(int argc, char *argv[]) { + if (argc != 4) { + usage(argv[0]); + return 1; + } + + unsigned int ifindex; + uint8_t d[ETH_ALEN]; + uint16_t ethertype; + + ifindex = if_nametoindex(argv[1]); + if (!ifindex) { + fprintf(stderr, "Error: invalid interface\n"); + usage(argv[0]); + return 1; + } + + if (sscanf(argv[2], "%hhx:%hhx:%hhx:%hhx:%hhx:%hhx", &d[0], &d[1], &d[2], &d[3], &d[4], &d[5]) != 6) { + fprintf(stderr, "Error: invalid destination address\n"); + usage(argv[0]); + return 1; + } + + if (sscanf(argv[3], "%hx", ðertype) != 1) { + fprintf(stderr, "Error: invalid ethertype\n"); + usage(argv[0]); + return 1; + } + + int fd = socket(AF_PACKET, SOCK_DGRAM, htons(ethertype)); + if (fd < 0) { + fprintf(stderr, "Error: socket: %m\n"); + return 1; + } + + const size_t buf_len = 65536; + uint8_t buf[buf_len]; + size_t pos = 0; + + while (!feof(stdin) && !ferror(stdin)) { + int read = fread(buf+pos, 1, buf_len-pos, stdin); + + if (read <= 0) + break; + + pos += read; + } + + if (pos < 46) { + /* don't send invalid short frames */ + memset(buf+pos, 0, 46-pos); + pos = 46; + } + + struct sockaddr_ll sa; + memset(&sa, 0, sizeof(sa)); + sa.sll_family = AF_PACKET; + sa.sll_protocol = htons(ethertype); + sa.sll_ifindex = ifindex; + sa.sll_halen = ETH_ALEN; + memcpy(sa.sll_addr, d, ETH_ALEN); + + if (sendto(fd, buf, pos, 0, (struct sockaddr*)&sa, sizeof(sa)) < 0) { + fprintf(stderr, "Error: sendto: %m\n"); + return 1; + } + + close(fd); + + return 0; +} |