diff options
author | Ian Moffett <ian@osmora.org> | 2025-09-24 20:58:52 -0400 |
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committer | Ian Moffett <ian@osmora.org> | 2025-09-24 20:58:52 -0400 |
commit | 570dc38023cac588a66118e8beb8dba66a3ec459 (patch) | |
tree | e330acd2f1dc7105523467c362f36b6d6806c612 /src | |
parent | e42e9220a91da7f83b4754be690a67a5ef65eed0 (diff) |
dgram: Add datagram layer
Signed-off-by: Ian Moffett <ian@osmora.org>
Diffstat (limited to 'src')
-rw-r--r-- | src/dgram/dgram_subr.c | 49 | ||||
-rw-r--r-- | src/include/dgram.h | 87 | ||||
-rw-r--r-- | src/main.c | 13 |
3 files changed, 145 insertions, 4 deletions
diff --git a/src/dgram/dgram_subr.c b/src/dgram/dgram_subr.c new file mode 100644 index 0000000..d79386f --- /dev/null +++ b/src/dgram/dgram_subr.c @@ -0,0 +1,49 @@ +/* + * Copyright (c) 2023-2025 Ian Marco Moffett and the Osmora Team. + * 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. + * 3. Neither the name of Hyra nor the names of its + * contributors may be used to endorse or promote products derived from + * this software without specific prior written permission. + * + * 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 OWNER 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 <sys/errno.h> +#include <stdint.h> +#include <string.h> +#include "dgram.h" +#include "crc.h" + +int +dgram_load(uint16_t length, uint8_t port, struct onet_dgram *res) +{ + if (res == NULL) { + return -EINVAL; + } + + memset(res, 0, sizeof(*res)); + res->length = (length >> 8) & 0xFF; + res->length |= (length & 0xFF) << 8; + res->port = port; + res->crc32 = crc32(res, sizeof(*res)); + return 0; +} diff --git a/src/include/dgram.h b/src/include/dgram.h new file mode 100644 index 0000000..93b20e3 --- /dev/null +++ b/src/include/dgram.h @@ -0,0 +1,87 @@ +/* + * Copyright (c) 2023-2025 Ian Marco Moffett and the Osmora Team. + * 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. + * 3. Neither the name of Hyra nor the names of its + * contributors may be used to endorse or promote products derived from + * this software without specific prior written permission. + * + * 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 OWNER 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. + */ + +#ifndef DGRAM_H +#define DGRAM_H + +#include <stdint.h> +#include "if_ether.h" + +/* + * Represents an ONET datagram + * + * @crc32: CRC32 checksum of data + header + * @length: Packet length in bytes + * @reserved: Reserved for future use + * @reserved1: Reserved for future use + * @port: Datagram port number to send on + */ +struct onet_dgram { + uint32_t crc32; + uint16_t length; + uint16_t reserved; + uint16_t reserved1; + uint8_t port; +} __attribute__((packed)); + +/* + * Get the total length of a datagram including + * the length of the ethernet header and the header + * of the datagram itself. + */ +#define DGRAM_LEN(len) \ + (sizeof(struct onet_dgram) + sizeof(struct ether_hdr) + len) + +/* + * Get the start of the datagram header start by passing + * a pointer to the buffer that holds the entire packet + */ +#define DGRAM_HDR(packet_p) \ + ((void *)((char *)packet_p + sizeof(struct ether_hdr))) + +/* + * Get the start of the datagram data start by passing + * a pointer to the buffer that holds the entire packet + */ +#define DGRAM_DATA(packet_p) \ + ((char *)packet_p + sizeof(struct onet_dgram) + sizeof(struct ether_hdr)) + +/* + * Initialize an ONET datagram + * + * @length: Length of a packet to send + * @port: Port number to send on + * @res: Result is written here + * + * Returns zero on success, otherwise a less than zero + * value on failure. + */ +int dgram_load(uint16_t length, uint8_t port, struct onet_dgram *res); + +#endif /* DGRAM_H */ @@ -38,6 +38,7 @@ #include <unistd.h> #include <string.h> #include "if_ether.h" +#include "dgram.h" #define TEST_STR "Hello from o.1p!! Meow meow!" @@ -57,15 +58,18 @@ help(char **argv) static int data_send(void) { - char data[256], *p; + char data[DGRAM_LEN(128)], *p; struct sockaddr_ll saddr; struct ether_hdr *eth; + struct onet_dgram *dgram; struct ifreq ifr; int error, sockfd; - memset(data, 0, sizeof(data)); eth = (struct ether_hdr *)data; - p = &data[sizeof(eth) + 100]; + p = DGRAM_DATA(data); + dgram = DGRAM_HDR(data); + + memset(data, 0, sizeof(data)); memcpy(p, TEST_STR, sizeof(TEST_STR)); sockfd = socket(AF_PACKET, SOCK_RAW, IPPROTO_RAW); @@ -83,12 +87,13 @@ data_send(void) } /* - * Set up link layer sockaddr, load up the frame + * Set up link layer sockaddr, load up the frame, datagram * and send it off. */ saddr.sll_ifindex = ifr.ifr_ifindex; saddr.sll_halen = ETH_ALEN; ether_load_route(0x54E1AD2CAE48, 0xFFFFFFFFFFFF, eth); + dgram_load(sizeof(TEST_STR), 50, dgram); sendto( sockfd, &data, sizeof(data), 0, (struct sockaddr *)&saddr, sizeof(struct sockaddr_ll) |