/* called by tun/tap_send routines */ static int tuntap_do_send (int fd, struct pbuf *p) { #ifdef HAVE_LINUX_IF_TUN_H pbuf_raise (p, 4); p->d[0] = p->d[1] = 0; PUT_16 (p->d + 2, ETH_P_IPV6); #endif return write (fd, p->d, p->dlen) < 0 ? -1 : 0; }
int add_query(struct dns_hdr *hdr, void *where, char *name, t_conf *conf, uint16_t type) { struct req_hdr *req; size_t query_len; int actual_len; query_len = strlen(name) + 1; actual_len = where - (void *)hdr; if ((query_len + actual_len + RR_HDR_SIZE) > MAX_DNS_LEN) return (-1); PUT_16(&hdr->qdcount, GET_16(&hdr->qdcount)+1); strcpy(where , name); req = (struct req_hdr *) (where + query_len); PUT_16(&req->qtype, type); PUT_16(&req->qclass, CLASS_IN); return ((int) (JUMP_REQ_HDR(req) - (char *)(hdr))); }
void *add_reply(struct dns_hdr *hdr, void *where, uint16_t type, char *encoded_data) { struct rr_hdr *rr; uint16_t *compress; int len; PUT_16(&hdr->ancount, GET_16(&hdr->ancount)+1); hdr->arcount = 0; compress = where; PUT_16(compress, sizeof(struct dns_hdr) | COMPRESS_FLAG); rr = where + sizeof(uint16_t); PUT_16(&rr->type, type); PUT_16(&rr->klass, CLASS_IN); PUT_16(&rr->ttl, 0); where = JUMP_RR_HDR(rr); strcpy(where, encoded_data); if (type == TYPE_TXT) dns_encode(where); len = strlen(where); PUT_16(&rr->rdlength,len); return (where + len); }
int main(int ac, char **av) { int fd, n, i; unsigned long ph, ps, np; long nnote, nnote2, ns; if (ac != 2) { fprintf(stderr, "Usage: %s elf-file\n", av[0]); exit(1); } fd = open(av[1], O_RDWR); if (fd < 0) { perror(av[1]); exit(1); } nnote = 12 + ROUNDUP(strlen(arch) + 1) + sizeof(descr); nnote2 = 12 + ROUNDUP(strlen(rpaname) + 1) + sizeof(rpanote); n = read(fd, buf, sizeof(buf)); if (n < 0) { perror("read"); exit(1); } if (memcmp(&buf[E_IDENT+EI_MAGIC], elf_magic, 4) != 0) goto notelf; e_class = buf[E_IDENT+EI_CLASS]; if (e_class != ELFCLASS32 && e_class != ELFCLASS64) goto notelf; e_data = buf[E_IDENT+EI_DATA]; if (e_data != ELFDATA2MSB && e_data != ELFDATA2LSB) goto notelf; if (n < E_HSIZE) goto notelf; ph = (e_class == ELFCLASS32 ? GET_32(E_PHOFF) : GET_64(E_PHOFF)); ps = GET_16(E_PHENTSIZE); np = GET_16(E_PHNUM); if (ph < E_HSIZE || ps < PH_HSIZE || np < 1) goto notelf; if (ph + (np + 2) * ps + nnote + nnote2 > n) goto nospace; for (i = 0; i < np; ++i) { if (GET_32(ph + PH_TYPE) == PT_NOTE) { fprintf(stderr, "%s already has a note entry\n", av[1]); exit(0); } ph += ps; } /* XXX check that the area we want to use is all zeroes */ for (i = 0; i < 2 * ps + nnote + nnote2; ++i) if (buf[ph + i] != 0) goto nospace; /* fill in the program header entry */ ns = ph + 2 * ps; PUT_32(ph + PH_TYPE, PT_NOTE); if (e_class == ELFCLASS32) PUT_32(ph + PH_OFFSET, ns); else PUT_64(ph + PH_OFFSET, ns); if (e_class == ELFCLASS32) PUT_32(ph + PH_FILESZ, nnote); else PUT_64(ph + PH_FILESZ, nnote); /* fill in the note area we point to */ /* XXX we should probably make this a proper section */ PUT_32(ns, strlen(arch) + 1); PUT_32(ns + 4, N_DESCR * 4); PUT_32(ns + 8, 0x1275); strcpy((char *) &buf[ns + 12], arch); ns += 12 + strlen(arch) + 1; for (i = 0; i < N_DESCR; ++i, ns += 4) PUT_32BE(ns, descr[i]); /* fill in the second program header entry and the RPA note area */ ph += ps; PUT_32(ph + PH_TYPE, PT_NOTE); if (e_class == ELFCLASS32) PUT_32(ph + PH_OFFSET, ns); else PUT_64(ph + PH_OFFSET, ns); if (e_class == ELFCLASS32) PUT_32(ph + PH_FILESZ, nnote); else PUT_64(ph + PH_FILESZ, nnote2); /* fill in the note area we point to */ PUT_32(ns, strlen(rpaname) + 1); PUT_32(ns + 4, sizeof(rpanote)); PUT_32(ns + 8, 0x12759999); strcpy((char *) &buf[ns + 12], rpaname); ns += 12 + ROUNDUP(strlen(rpaname) + 1); for (i = 0; i < N_RPA_DESCR; ++i, ns += 4) PUT_32BE(ns, rpanote[i]); /* Update the number of program headers */ PUT_16(E_PHNUM, np + 2); /* write back */ lseek(fd, (long) 0, SEEK_SET); i = write(fd, buf, n); if (i < 0) { perror("write"); exit(1); } if (i < n) { fprintf(stderr, "%s: write truncated\n", av[1]); exit(1); } exit(0); notelf: fprintf(stderr, "%s does not appear to be an ELF file\n", av[1]); exit(1); nospace: fprintf(stderr, "sorry, I can't find space in %s to put the note\n", av[1]); exit(1); }
static int mpv_send( struct rtp_endpoint *ep, void *d ) { struct rtp_mpv *out = (struct rtp_mpv *)d; int i, j, space, off, min_space; struct iovec v[48]; unsigned char vhdr[4]; /* MPEG video header always follows the RTP header */ PUT_16( vhdr, out->temporal_reference ); vhdr[2] = out->picture_type; /* will be different for each frame */ vhdr[3] = out->vectors; v[1].iov_base = vhdr; v[1].iov_len = 4; i = 0; j = 2; space = ep->max_data_size - 4; /* If this is an I frame, insert the saved Video Sequence Header */ if( out->picture_type == 1 ) { vhdr[2] |= 0x20; /* Sequence-header-present bit */ /* add the block to the frame */ v[j].iov_base = out->vsh; v[j].iov_len = out->vsh_len; space -= v[j].iov_len; ++j; } for( i = 0; i < out->blk_count; ++i ) { /* We can fragment slices, but after the initial fragment, * all the remaining fragments must be put into their own * packets. This means fragmentation only makes sense if * the slice is larger than our MTU. */ if( out->blk[i].len > ep->max_data_size - 4 ) min_space = 4; else min_space = out->blk[i].len; /* If we don't have enough space for this entire block, or if * we're fragmenting and we don't have enough space for the * start code, first send out the previous blocks. */ if( space < min_space ) { if( send_rtp_packet( ep, v, j, out->timestamp, 0 ) < 0 ) return -1; j = 2; vhdr[2] = out->picture_type; space = ep->max_data_size - 4; } /* add the block to the frame */ v[j].iov_base = out->blk[i].d; v[j].iov_len = out->blk[i].len; /* if this is a slice, set the Beginning-of-slice bit */ if( out->blk[i].d[3] > 0 && out->blk[i].d[3] <= 0xAF ) vhdr[2] |= 0x10; /* if the entire block fit, go on to the next block */ if( v[j].iov_len <= space ) { /* if this is a slice, set the End-of-slice bit */ if( out->blk[i].d[3] > 0 && out->blk[i].d[3] <= 0xAF ) vhdr[2] |= 0x08; space -= v[j].iov_len; ++j; continue; } /* block did not fit, so send the first fragment */ v[j].iov_len = space; /* the last byte of the packet is not the end of a slice, so * clear the End-of-slice bit */ vhdr[2] &= ~0x08; if( send_rtp_packet( ep, v, j + 1, out->timestamp, 0 ) < 0 ) return -1; /* send all remaining fragments by themselves */ for( off = space; off < out->blk[i].len; off += v[2].iov_len ) { vhdr[2] = out->picture_type; v[2].iov_base = out->blk[i].d + off; v[2].iov_len = out->blk[i].len - off; if( v[2].iov_len > ep->max_data_size - 4 ) v[2].iov_len = ep->max_data_size - 4; else vhdr[2] |= 0x08; /* End-of-slice bit */ if( send_rtp_packet( ep, v, 3, out->timestamp, ( vhdr[2] & 0x08 ) && ( ( i + 1 ) == out->blk_count ) ) < 0 ) return -1; } j = 2; vhdr[2] = out->picture_type; space = ep->max_data_size - 4; } /* send any unsent blocks */ if( j > 2 && send_rtp_packet( ep, v, j, out->timestamp, 1 ) < 0 ) return -1; return 0; }