diff options
| -rw-r--r-- | econproxy.c | 105 |
1 files changed, 79 insertions, 26 deletions
diff --git a/econproxy.c b/econproxy.c index df9545f..ea20f54 100644 --- a/econproxy.c +++ b/econproxy.c @@ -87,6 +87,52 @@ send_packet(struct ep *ep) return writev(ep->ec_fd, ep->iov, i); } +static int +read_packet(struct ep *ep) +{ + ssize_t len; + + init_iov(ep); + + len = readv(ep->ec_fd, ep->iov, 3); + if (len < 0) + return -1; + + if (len < sizeof(struct econ_header)) { + fprintf(stderr, "read_packet: error: incomplete header\n"); + return -1; + } + + if (len < sizeof(struct econ_header) + ep->ehdr.datasize) { + fprintf(stderr, "packet has invalid datasize\n"); + return -1; + } + + if (ep->ehdr.datasize > 0) { + if (ep->ehdr.datasize < sizeof(struct econ_command)) { + fprintf(stderr, + "read_packet: error: command to short\n"); + return -1; + } + + if (ep->ecmd.recordCount > 0) { + if (ep->ecmd.recordCount > 1) { + fprintf(stderr, "read_packet: did not expect a" + " packet with more that one record: %d, datasize: %d.\n", + ep->ecmd.recordCount, ep->ehdr.datasize); + return -1; + } + if (ep->ehdr.datasize != (sizeof (struct econ_command) + + sizeof (struct econ_record))) { + fprintf(stderr, "read_packet: datasize incorrect\n"); + return -1; + } + } + } + + return 0; +} + static void write_ppm(FILE *img, int width, int height, int bpp, uint8_t *buf) { @@ -115,35 +161,43 @@ ep_keepalive(struct ep *ep) static int ep_get_clientinfo(struct ep *ep) { - char buf[BUFSIZ], buf2[BUFSIZ]; - size_t len; - init_packet(ep, E_CMD_IPSEARCH); send_packet(ep); - len = read(ep->ec_fd, buf, BUFSIZ); - struct econ_header *hdr = (void *) buf; - printf("cmd: %d, len: %zd\n", hdr->commandID, len); + if (read_packet(ep) < 0) + return -1; + if (ep->ehdr.commandID != E_CMD_CLIENTINFO) { + fprintf(stderr, "expected clientinfo, got: %d\n", + ep->ehdr.commandID); + return -1; + } - if (len < (sizeof (struct econ_header) + - sizeof (struct econ_command) + - sizeof (struct econ_record))) { - fprintf(stderr, "error: Invalid packet received.\n"); + if (ep->ehdr.datasize == 0 || ep->ecmd.recordCount == 0) { + fprintf(stderr, "missing record in clientinfo\n"); return -1; } + printf("clientinfo: read cmd: %d\n", ep->ehdr.commandID); - struct econ_command *ecmd = (void *) (buf + sizeof (struct econ_header)); printf("clientinfo unknown value: %hu\n", - ecmd->command.clientinfo.unknown_field_1); + ep->ecmd.command.clientinfo.unknown_field_1); /* cache projUniqInfo needed for reqconnect */ - struct econ_record *erec = (void *) (buf + sizeof (struct econ_header) + - sizeof (struct econ_command)); - memcpy(ep->projUniqInfo, erec->projUniqInfo, ECON_UNIQINFO_LENGTH); + memcpy(ep->projUniqInfo, ep->erec.projUniqInfo, ECON_UNIQINFO_LENGTH); #if 1 - len = read(ep->ec_fd, buf2, BUFSIZ); - hdr = (void *) buf2; + char buf[BUFSIZ]; + ssize_t len = read(ep->ec_fd, buf, BUFSIZ); + struct econ_header *hdr = (void *) buf; printf("cmd: %d, len: %zd\n", hdr->commandID, len); +#if 0 + if (read_packet(ep) < 0) + return -1; +#endif + + if (hdr->commandID != 21) { + fprintf(stderr, "expected ex clientinfo (21), got: %d\n", + hdr->commandID); + return -1; + } #endif return 0; @@ -204,7 +258,8 @@ ep_reqconnect(struct ep *ep, rfbServerInitMsg *vnes) send_packet(ep); - readv(ep->ec_fd, ep->iov, 3); + if (read_packet(ep) < 0) + return -1; if (ep->ehdr.commandID != E_CMD_CONNECTED) { fprintf(stderr, "failed to connect: command was: %d\n", ep->ehdr.commandID); @@ -233,15 +288,8 @@ create_data_sockets(struct ep *ep, const char *beamer) static int ep_read_ack(struct ep *ep) { - size_t len; - - init_iov(ep); - - len = readv(ep->ec_fd, ep->iov, 2); - if (len < ep->iov[0].iov_len + ep->iov[1].iov_len) { - fprintf(stderr, "error: command received is to short\n"); + if (read_packet(ep) < 0) return -1; - } switch (ep->ehdr.commandID) { /* cack for connection video sockets */ @@ -258,6 +306,11 @@ ep_read_ack(struct ep *ep) return -1; } + if (ep->ehdr.datasize == 0) { + fprintf(stderr, "error: command 22 received is to short\n"); + return -1; + } + init_packet(ep, E_CMD_25); ep->ehdr.datasize = sizeof ep->ecmd; ep->ecmd.command.cmd25.unknown_field1 = 1; |