// L2TPNS: control
-char const *cvs_id_control = "$Id: control.c,v 1.2 2004-06-28 02:43:13 fred_nerk Exp $";
-
-#include <stdio.h>
-#include <arpa/inet.h>
-#include <errno.h>
-#include <fcntl.h>
-#include <malloc.h>
-#include <netdb.h>
+char const *cvs_id_control = "$Id: control.c,v 1.4 2004-12-16 08:49:53 bodea Exp $";
+
#include <string.h>
-#include <sys/time.h>
-#include <sys/types.h>
-#include <sys/socket.h>
-#include <netinet/in.h>
-#include <signal.h>
-#include <stdarg.h>
-#include <stdlib.h>
-#include <unistd.h>
-#include <time.h>
+#include "l2tpns.h"
#include "control.h"
-int new_packet(short type, char *packet)
+int pack_control(char *data, int len, uint8_t type, int argc, char *argv[])
{
- int id = (time(NULL) ^ (rand() * 1024*1024));
+ struct nsctl_packet pkt;
+ struct nsctl_args arg;
+ char *p = pkt.argv;
+ int sz = (p - (char *) &pkt);
+
+ if (len > sizeof(pkt))
+ len = sizeof(pkt);
+
+ if (argc > 0xff)
+ argc = 0xff; // paranoia
+
+ pkt.magic = ntohs(NSCTL_MAGIC);
+ pkt.type = type;
+ pkt.argc = argc;
+
+ while (argc-- > 0)
+ {
+ char *a = *argv++;
+ int s = strlen(a);
+
+ if (s > sizeof(arg.value))
+ s = sizeof(arg.value); // silently truncate
+
+ arg.len = s;
+ s += sizeof(arg.len);
+
+ if (sz + s > len)
+ return -1; // overflow
- *(short *)(packet + 0) = ntohs(0x9012);
- *(short *)(packet + 2) = ntohs(type);
- *(int *)(packet + 6) = ntohl(id);
+ if (arg.len)
+ memcpy(arg.value, a, arg.len);
- return 10;
+ memcpy(p, &arg, s);
+ sz += s;
+ p += s;
+ }
+
+ /*
+ * terminate: this is both a sanity check and additionally
+ * ensures that there's a spare byte in the packet to null
+ * terminate the last argument when unpacking (see unpack_control)
+ */
+ if (sz + sizeof(arg.len) > len)
+ return -1; // overflow
+
+ arg.len = 0xff;
+ memcpy(p, &arg.len, sizeof(arg.len));
+
+ sz += sizeof(arg.len);
+ memcpy(data, &pkt, sz);
+
+ return sz;
}
-int send_packet(int sockfd, int dest_ip, int dest_port, char *packet, int len)
+int unpack_control(struct nsctl *control, char *data, int len)
{
- struct sockaddr_in addr;
+ struct nsctl_packet pkt;
+ char *p = pkt.argv;
+ int sz = (p - (char *) &pkt);
+ int i;
+
+ if (len < sz)
+ return NSCTL_ERR_SHORT;
+
+ if (len > sizeof(pkt))
+ return NSCTL_ERR_LONG;
+
+ memcpy(&pkt, data, len);
+ if (ntohs(pkt.magic) != NSCTL_MAGIC)
+ return NSCTL_ERR_MAGIC;
+
+ switch (pkt.type)
+ {
+ case NSCTL_REQ_LOAD:
+ case NSCTL_REQ_UNLOAD:
+ case NSCTL_REQ_HELP:
+ case NSCTL_REQ_CONTROL:
+ case NSCTL_RES_OK:
+ case NSCTL_RES_ERR:
+ control->type = pkt.type;
+ break;
- *(short *)(packet + 4) = ntohs(len);
+ default:
+ return NSCTL_ERR_TYPE;
+ }
- memset(&addr, 0, sizeof(addr));
- addr.sin_family = AF_INET;
- *(int*)&addr.sin_addr = htonl(dest_ip);
- addr.sin_port = htons(dest_port);
- if (sendto(sockfd, packet, len, 0, (void *) &addr, sizeof(addr)) < 0)
+ control->argc = pkt.argc;
+ for (i = 0; i <= control->argc; i++)
+ {
+ unsigned s;
+
+ if (len < sz + 1)
+ return NSCTL_ERR_SHORT;
+
+ s = (uint8_t) *p;
+ *p++ = 0; // null terminate previous arg
+ sz++;
+
+ if (i < control->argc)
+ {
+ if (len < sz + s)
+ return NSCTL_ERR_SHORT;
+
+ control->argv[i] = p;
+ p += s;
+ sz += s;
+ }
+ else
{
- perror("sendto");
- return 0;
+ /* check for terminator */
+ if (s != 0xff)
+ return NSCTL_ERR_SHORT;
}
- return 1;
-}
+ }
-int read_packet(int sockfd, char *packet)
-{
- struct sockaddr_in addr;
- int alen = sizeof(addr);
- memset(&addr, 0, sizeof(addr));
- return recvfrom(sockfd, packet, 1400, 0, (void *) &addr, &alen);
+ if (sz != len)
+ return NSCTL_ERR_LONG; // trailing cr*p
+
+ return control->type;
}
-void dump_packet(char *packet, FILE *stream)
+void dump_control(struct nsctl *control, FILE *stream)
{
- if (htons(*(short *)(packet + 0)) != 0x9012)
- {
- fprintf(stream, "Invalid packet identifier %x\n", htons(*(short *)(packet + 0)));
- return;
- }
- fprintf(stream, "Control packet:\n");
- fprintf(stream, " Type: %d\n", htons(*(short *)(packet + 2)));
- fprintf(stream, " Length: %d\n", htons(*(short *)(packet + 4)));
- fprintf(stream, " Identifier: %x\n", htonl(*(int *)(packet + 6)));
- fprintf(stream, "\n");
-}
+ char *type = "*unknown*";
+ if (!stream)
+ stream = stdout;
+ switch (control->type)
+ {
+ case NSCTL_REQ_LOAD: type = "NSCTL_REQ_LOAD"; break;
+ case NSCTL_REQ_UNLOAD: type = "NSCTL_REQ_UNLOAD"; break;
+ case NSCTL_REQ_HELP: type = "NSCTL_REQ_HELP"; break;
+ case NSCTL_REQ_CONTROL: type = "NSCTL_REQ_CONTROL"; break;
+ case NSCTL_RES_OK: type = "NSCTL_RES_OK"; break;
+ case NSCTL_RES_ERR: type = "NSCTL_RES_ERR"; break;
+ }
+
+ fprintf(stream, "Control packet:\n");
+ fprintf(stream, " Type: %d (%s)\n", (int) control->type, type);
+ fprintf(stream, " Args: %d", (int) control->argc);
+ if (control->argc)
+ {
+ int i;
+ fprintf(stream, " (\"");
+ for (i = 0; i < control->argc; i++)
+ fprintf(stream, "%s%s", i ? "\", \"" : "", control->argv[i]);
+
+ fprintf(stream, "\")");
+ }
+
+ fprintf(stream, "\n\n");
+}
projects / l2tpns.git / blobdiff