ref: d9d2925fa024c2eceeea18c9b3afda30af96301e
dir: /sys/src/cmd/ip/torrent.c/
#include <u.h> #include <libc.h> #include <mp.h> #include <libsec.h> typedef struct Dict Dict; typedef struct Piece Piece; typedef struct File File; typedef struct Stats Stats; struct Dict { Dict *val; Dict *next; char *start, *end; int len; char typ; // i, d, s, l char str[]; }; struct Piece { uchar *hash; int len; int brk; }; struct File { File *next; char *name; int fd; vlong off; vlong len; }; struct Stats { Lock; vlong up; vlong down; vlong left; }; enum { MAXIO = 16*1024, SRVPROCS = 16, CLIPROCS = 16, }; int debug; int nproc = 1; int killgroup = -1; int port = 6881; char *deftrack = "http://exodus.desync.com/announce"; char *mntweb = "/mnt/web"; char *useragent = "torrent"; uchar infohash[20]; uchar peerid[20]; int blocksize; int npieces; Piece *pieces; int nhavemap; uchar *havemap; int nhavepieces; File *files; Stats stats; int finished(void) { return nhavepieces >= npieces; } void freedict(Dict *d) { if(d){ if(d->val != d) freedict(d->val); freedict(d->next); free(d); } } char* bparse(char *s, char *e, Dict **dp) { char *x, t; Dict *d; int n; *dp = nil; if(s >= e) return e; t = *s; switch(t){ case 'd': case 'l': x = s++; d = nil; while(s < e){ if(*s == 'e'){ s++; break; } if(t == 'd'){ s = bparse(s, e, dp); if((d = *dp) == nil) break; } else d = *dp = mallocz(sizeof(*d), 1); d->typ = t; d->start = x; if(s < e){ s = bparse(s, e, &d->val); dp = &d->next; d->end = s; } x = s; } if(d) d->end = s; return s; case 'i': x = ++s; if((s = memchr(x, 'e', e - x)) == nil) return e; n = s - x; s++; break; default: if((x = memchr(s, ':', e - s)) == nil) return e; x++; if((n = atoi(s)) < 0) return e; s = x + n; if((s > e) || (s < x)){ n = e - x; s = e; } t = 's'; } d = mallocz(sizeof(*d) + n+1, 1); d->typ = t; memmove(d->str, x, d->len = n); d->str[n] = 0; *dp = d; return s; } char* dstr(Dict *d) { if(d && (d->typ == 's' || d->typ == 'i')) return d->str; return nil; } Dict* dlook(Dict *d, char *s) { for(; d && d->typ == 'd'; d = d->next) if(d->len && strcmp(d->str, s) == 0) return d->val; return nil; } int readall(int fd, char **p) { int n, r; n = 0; *p = nil; while(*p = realloc(*p, n+1024)){ if((r = read(fd, *p+n, 1024)) <= 0) break; n += r; } return n; } int rwpiece(int wr, int index, uchar *data, int len, int poff) { vlong off; int n, m; File *f; if(len <= 0 || poff < 0 || poff >= pieces[index].len) return 0; if(len+poff > pieces[index].len) len = pieces[index].len - poff; off = (vlong)index * (vlong)blocksize; off += poff; for(f = files; f; f = f->next) if((f->off+f->len) > off) break; off -= f->off; n = ((off + len) > f->len) ? f->len - off : len; if((n = (wr ? pwrite(f->fd, data, n, off) : pread(f->fd, data, n, off))) <= 0) return -1; if((m = rwpiece(wr, index, data + n, len - n, poff + n)) < 0) return -1; return n+m; } int havepiece(int x) { uchar *p, m, hash[20]; int n; m = 0x80>>(x&7); if(havemap[x>>3] & m) return 1; p = malloc(blocksize); n = pieces[x].len; if(rwpiece(0, x, p, n, 0) != n){ free(p); return 0; } sha1(p, n, hash, nil); free(p); if(memcmp(hash, pieces[x].hash, 20)) return 0; lock(&stats); if((havemap[x>>3] & m) == 0){ havemap[x>>3] |= m; nhavepieces++; stats.left -= pieces[x].len; } unlock(&stats); return 1; } int pickpiece(uchar *map) { int i, x, r, k; uchar m; r = -1; k = 0; for(i = 0; i<nhavemap; i++){ if(map[i] == 0) continue; for(x = i<<3, m = 0x80; m; m >>= 1, x++){ if((~map[i] | havemap[i]) & m) continue; if(nrand(++k) == 0) r = x; } } return r; } int unpack(uchar *s, int n, char *fmt, ...) { va_list arg; uchar *b, *e; b = s; e = b + n; va_start(arg, fmt); for(; *fmt; fmt++) { switch(*fmt){ case '_': s++; break; case 'b': if(s+1 > e) goto Err; *va_arg(arg, int*) = *s++; break; case 'w': if(s+2 > e) goto Err; *va_arg(arg, int*) = s[0]<<8 | s[1]; s += 2; break; case 'l': if(s+4 > e) goto Err; *va_arg(arg, int*) = s[0]<<24 | s[1]<<16 | s[2]<<8 | s[3]; s += 4; break; case 'v': if(s+4 > e) goto Err; *va_arg(arg, vlong*) = (vlong)s[0]<<56 | (vlong)s[1]<<48 | (vlong)s[2]<<40 | (vlong)s[3]<<32 | (vlong)s[4]<<24 | (vlong)s[5]<<16 | (vlong)s[6]<<8 | (vlong)s[7]; s += 8; break; } } va_end(arg); return s - b; Err: va_end(arg); return -1; } int pack(uchar *s, int n, char *fmt, ...) { va_list arg; uchar *b, *e; vlong v; int i; b = s; e = b + n; va_start(arg, fmt); for(; *fmt; fmt++) { switch(*fmt){ case '_': i = 0; if(0){ case 'b': i = va_arg(arg, int); } if(s+1 > e) goto Err; *s++ = i & 0xFF; break; case 'w': i = va_arg(arg, int); if(s+2 > e) goto Err; *s++ = (i>>8) & 0xFF; *s++ = i & 0xFF; break; case 'l': i = va_arg(arg, int); if(s+4 > e) goto Err; *s++ = (i>>24) & 0xFF; *s++ = (i>>16) & 0xFF; *s++ = (i>>8) & 0xFF; *s++ = i & 0xFF; break; case 'v': v = va_arg(arg, vlong); if(s+8 > e) goto Err; *s++ = (v>>56) & 0xFF; *s++ = (v>>48) & 0xFF; *s++ = (v>>40) & 0xFF; *s++ = (v>>32) & 0xFF; *s++ = (v>>24) & 0xFF; *s++ = (v>>16) & 0xFF; *s++ = (v>>8) & 0xFF; *s++ = v & 0xFF; break; case '*': i = va_arg(arg, int); if(s+i > e) goto Err; memmove(s, va_arg(arg, void*), i); s += i; break; } } va_end(arg); return s - b; Err: va_end(arg); return -1; } int peer(int fd, int incoming, char *addr) { uchar buf[64+MAXIO], *map, *told, *p, m; int mechoking, hechoking; int mewant, hewant; int workpiece; int i, o, l, x, n; if(debug) fprint(2, "peer %s: %s connected\n", addr, incoming ? "incoming" : "outgoing"); for(i=0; i<2; i++){ if((incoming && i) || (!incoming && !i)){ if(debug) fprint(2, "peer %s: -> handshake\n", addr); n = pack(buf, sizeof(buf), "*________**", 20, "\x13BitTorrent protocol", sizeof(infohash), infohash, sizeof(peerid), peerid); if(write(fd, buf, n) != n) return 1; } if((incoming && !i) || (!incoming && i)){ n = 20 + 8 + sizeof(infohash); if((n = readn(fd, buf, n)) != n) return 1; if(memcmp(buf, "\x13BitTorrent protocol", 20)) return 0; if(memcmp(infohash, buf + 20 + 8, sizeof(infohash))) return 0; if(debug) fprint(2, "peer %s: <- handshake\n", addr); } } if(readn(fd, buf, sizeof(peerid)) != sizeof(peerid)) return 1; if(memcmp(peerid, buf, sizeof(peerid)) == 0) return 0; if(debug) fprint(2, "peer %s: peerid %.*s\n", addr, sizeof(peerid), (char*)buf); mechoking = 1; hechoking = 1; mewant = 0; hewant = 0; workpiece = -1; map = mallocz(nhavemap, 1); told = malloc(nhavemap); if(debug) fprint(2, "peer %s: -> bitfield %d\n", addr, nhavemap); memmove(told, havemap, nhavemap); n = pack(buf, sizeof(buf), "lb*", nhavemap+1, 0x05, nhavemap, told); if(write(fd, buf, n) != n) goto Out; for(;;){ for(i=0; i<nhavemap; i++){ if(told[i] != havemap[i]){ for(x = i<<3, m = 0x80; m; m >>= 1, x++){ if((~havemap[i] | told[i] | map[i]) & m) continue; told[i] |= m; if(debug) fprint(2, "peer %s: -> have %d\n", addr, x); n = pack(buf, sizeof(buf), "lbl", 1+4, 0x04, x); if(write(fd, buf, n) != n) goto Out; } } if(!mewant && (map[i] & ~havemap[i])){ mewant = 1; if(debug) fprint(2, "peer %s: -> interested\n", addr); n = pack(buf, sizeof(buf), "lb", 1, 0x02); if(write(fd, buf, n) != n) goto Out; } } if(!hechoking && mewant){ x = workpiece; if(x < 0 || (havemap[x>>3]&(0x80>>(x&7))) != 0) x = pickpiece(map); if(x >= 0){ workpiece = x; o = pieces[x].brk; if(o < 0 || o >= pieces[x].len){ pieces[x].brk = 0; o = 0; } l = pieces[x].len - o; if(l > MAXIO) l = MAXIO; if(debug) fprint(2, "peer %s: -> request %d %d %d\n", addr, x, o, l); n = pack(buf, sizeof(buf), "lblll", 1+4+4+4, 0x06, x, o, l); if(write(fd, buf, n) != n) goto Out; } } if(mechoking && hewant){ mechoking = 0; if(debug) fprint(2, "peer %s: -> unchoke\n", addr); n = pack(buf, sizeof(buf), "lb", 1, 0x01); if(write(fd, buf, n) != n) goto Out; } if(readn(fd, buf, 4) != 4) break; unpack(buf, 4, "l", &n); if(n < 0 || n > sizeof(buf)) break; if(n == 0) continue; if(readn(fd, buf, n) != n) break; n--; p = buf+1; switch(*buf){ case 0x00: // Choke hechoking = 1; workpiece = -1; if(debug) fprint(2, "peer %s: <- choke\n", addr); break; case 0x01: // Unchoke hechoking = 0; if(debug) fprint(2, "peer %s: <- unchoke\n", addr); break; case 0x02: // Interested hewant = 1; if(debug) fprint(2, "peer %s: <- interested\n", addr); break; case 0x03: // Notinterested hewant = 0; if(debug) fprint(2, "peer %s: <- notinterested\n", addr); break; case 0x04: // Have <piceindex> if(unpack(p, n, "l", &x) < 0) goto Out; if(debug) fprint(2, "peer %s: <- have %d\n", addr, x); if(x < 0 || x >= npieces) continue; map[x>>3] |= 0x80>>(x&7); break; case 0x05: // Bitfield if(debug) fprint(2, "peer %s: <- bitfield %d\n", addr, n); if(n != nhavemap) continue; memmove(map, p, n); break; case 0x06: // Request <index> <begin> <length> if(unpack(p, n, "lll", &x, &o, &l) < 0) goto Out; if(debug) fprint(2, "peer %s: <- request %d %d %d\n", addr, x, o, l); if(x < 0 || x >= npieces) continue; if(!hewant || mechoking || (~havemap[x>>3]&(0x80>>(x&7)))) continue; if(debug) fprint(2, "peer %s: -> piece %d %d\n", addr, x, o); n = 4+1+4+4; if(l > MAXIO) l = MAXIO; if((l = rwpiece(0, x, buf + n, l, o)) <= 0) continue; n = pack(buf, sizeof(buf), "lbll", 1+4+4+l, 0x07, x, o); n += l; if(write(fd, buf, n) != n) goto Out; lock(&stats); stats.up += n; unlock(&stats); break; case 0x07: // Piece <index> <begin> <block> if(unpack(p, n, "ll", &x, &o) != 8) goto Out; p += 8; n -= 8; lock(&stats); stats.down += n; unlock(&stats); if(debug) fprint(2, "peer %s: <- piece %d %d %d\n", addr, x, o, n); if(x < 0 || x >= npieces) continue; if((havemap[x>>3]&(0x80>>(x&7))) != 0) continue; if(o < 0 || o >= pieces[x].len) continue; if(o+n > pieces[x].len) n = o - pieces[x].len; if((o > pieces[x].brk) || (o+n <= pieces[x].brk)) continue; n = rwpiece(1, x, p, n, o); if(n <= 0) continue; pieces[x].brk = o+n; if(o+n >= pieces[x].len && !havepiece(x)){ /* backoff from this piece for a while */ if(x == workpiece) workpiece = -1; } break; case 0x08: // Cancel <index> <begin> <length> if(unpack(p, n, "lll", &x, &o, &l) < 0) goto Out; if(debug) fprint(2, "peer %s: <- cancel %d %d %d\n", addr, x, o, l); break; case 0x09: // Port <port> if(unpack(p, n, "l", &x) < 0) goto Out; if(debug) fprint(2, "peer %s: <- port %d\n", addr, x); break; } } Out: free(told); free(map); return 1; } void server(void) { char addr[64], adir[40], ldir[40]; int afd, lfd, dfd, pid, nprocs; NetConnInfo *ni; afd = -1; nprocs = 0; for(port=6881; port<6890; port++){ snprint(addr, sizeof(addr), "tcp!*!%d", port); if((afd = announce(addr, adir)) >= 0) break; } if(afd < 0){ fprint(2, "announce: %r"); return; } if(rfork(RFFDG|RFPROC|RFMEM)) return; for(;;){ if((lfd = listen(adir, ldir)) < 0){ fprint(2, "listen: %r"); break; } while(nprocs >= SRVPROCS) if(waitpid() > 0) nprocs--; nprocs++; if(pid = rfork(RFFDG|RFPROC|RFMEM)){ if(pid < 0) nprocs--; close(lfd); continue; } if((dfd = accept(lfd, ldir)) < 0){ fprint(2, "accept: %r"); break; } ni = getnetconninfo(ldir, dfd); peer(dfd, 1, ni ? ni->raddr : "???"); if(ni) freenetconninfo(ni); break; } exits(0); } void client(char *ip, char *port) { static Dict *peerqh, *peerqt; static QLock peerslk; static int nprocs; char *addr; Dict *d; int fd; if(ip == nil || port == nil) return; d = mallocz(sizeof(*d) + 64, 1); snprint(addr = d->str, 64, "tcp!%s!%s", ip, port); qlock(&peerslk); if(dlook(peerqh, addr)){ qunlock(&peerslk); free(d); return; } d->len = strlen(addr); d->typ = 'd'; d->val = d; /* enqueue to front */ if((d->next = peerqh) == nil) peerqt = d; peerqh = d; if(nprocs >= CLIPROCS){ qunlock(&peerslk); return; } nprocs++; qunlock(&peerslk); if(rfork(RFFDG|RFPROC|RFMEM|RFNOWAIT)) return; for(;;){ qlock(&peerslk); /* dequeue and put to tail */ if(d = peerqh){ if((peerqh = d->next) == nil) peerqt = nil; d->next = nil; if(peerqt) peerqt->next = d; else peerqh = d; peerqt = d; } else nprocs--; qunlock(&peerslk); if(d == nil) exits(0); addr = d->str; if(debug) fprint(2, "client %s\n", addr); if((fd = dial(addr, nil, nil, nil)) >= 0){ peer(fd, 0, addr); close(fd); } sleep(1000+nrand(5000)); } } int hopen(char *url, ...) { int conn, ctlfd, fd, n; char buf[1024+1]; va_list arg; snprint(buf, sizeof buf, "%s/clone", mntweb); if((ctlfd = open(buf, ORDWR)) < 0) return -1; if((n = read(ctlfd, buf, sizeof buf-1)) <= 0){ close(ctlfd); return -1; } buf[n] = 0; conn = atoi(buf); va_start(arg, url); strcpy(buf, "url "); n = 4+vsnprint(buf+4, sizeof(buf)-4, url, arg); va_end(arg); if(write(ctlfd, buf, n) != n){ ErrOut: close(ctlfd); return -1; } if(useragent != nil && useragent[0] != '\0'){ n = snprint(buf, sizeof buf, "useragent %s", useragent); write(ctlfd, buf, n); } snprint(buf, sizeof buf, "%s/%d/body", mntweb, conn); if((fd = open(buf, OREAD)) < 0) goto ErrOut; close(ctlfd); return fd; } void webseed(Dict *w, File *f) { int fd, err, n, m, o, p, x, y; uchar buf[MAXIO]; vlong off, len; Dict *w0; char *s; if(w == nil || f == nil || finished()) return; if(rfork(RFPROC|RFMEM)) return; w0 = w; Retry: if(debug) fprint(2, "webseed %s %s\n", w->str, f->name); s = strrchr(w->str, '/'); if(s && s[1] == 0) fd = hopen("%s%s", w->str, f->name); else fd = hopen("%s", w->str); if(fd < 0){ Error: if(debug) fprint(2, "webseed %s %s: %r\n", w->str, f->name); if(finished()) exits(0); if((w = w->next) == w0) exits(0); goto Retry; } err = 0; off = f->off; len = f->len; while(len > 0 && !finished()){ m = sizeof(buf); if(len < m) m = len; if((n = read(fd, buf, m)) <= 0) break; x = off / blocksize; p = off - (vlong)x*blocksize; off += n; len -= n; y = off / blocksize; o = 0; while(n > 0){ m = pieces[x].len - p; if(m > n) m = n; if((havemap[x>>3] & (0x80>>(x&7))) == 0) rwpiece(1, x, buf+o, m, p); if(x == y) break; o += m; n -= m; p = 0; if(havepiece(x++)) continue; if(++err > 10){ close(fd); werrstr("file corrupted"); goto Error; } } } havepiece(off / blocksize); havepiece(f->off / blocksize); close(fd); exits(0); } void clients4(uchar *p, int len) { char ip[16], port[6]; while(len >= 6){ len -= 6; snprint(ip, sizeof(ip), "%d.%d.%d.%d", p[0], p[1], p[2], p[3]); snprint(port, sizeof(port), "%d", p[4]<<8 | p[5]); p += 6; client(ip, port); } } void webtracker(char *url) { char *event, *p; Dict *d, *l; int n, fd; if(rfork(RFPROC|RFMEM)) return; if(debug) fprint(2, "webtracker %s\n", url); event = "&event=started"; for(;;){ vlong up, down, left; lock(&stats); up = stats.up; down = stats.down; left = stats.left; unlock(&stats); d = nil; if((fd = hopen("%s?info_hash=%.*H&peer_id=%.*H&port=%d&" "uploaded=%lld&downloaded=%lld&left=%lld&compact=1&no_peer_id=1%s", url, sizeof(infohash), infohash, sizeof(peerid), peerid, port, up, down, left, event)) >= 0){ event = ""; n = readall(fd, &p); close(fd); bparse(p, p+n, &d); free(p); } else if(debug) fprint(2, "tracker %s: %r\n", url); /* check errors and warnings */ if(p = dstr(dlook(d, "failure reason"))) { if(debug) fprint(2, "tracker failure: %s\n", p); exits(0); } if(p = dstr(dlook(d, "warning message"))) if(debug) fprint(2, "tracker warning: %s\n", p); if(l = dlook(d, "peers")){ if(l->typ == 's') clients4((uchar*)l->str, l->len); else for(; l && l->typ == 'l'; l = l->next) client(dstr(dlook(l->val, "ip")), dstr(dlook(l->val, "port"))); } n = 0; if(p = dstr(dlook(d, "interval"))) n = atoi(p); if(n < 10 | n > 60*60) n = 2*60; freedict(d); sleep(n * 1000 + nrand(5000)); } } int udpaddr(char addr[64], int naddr, char *url) { int port; char *x; if((url = strchr(url, ':')) == nil) return -1; url++; while(*url == '/') url++; if(x = strchr(url, ':')){ port = atoi(x+1); } else { port = 80; if((x = strchr(url, '/')) == nil) x = strchr(url, 0); } snprint(addr, naddr, "udp!%.*s!%d", (int)(x-url), url, port); return 0; } void udptracker(char *url) { int fd, event, n, m, a, i; int transid, interval; vlong connid; uchar buf[MAXIO]; char addr[64]; if(udpaddr(addr, sizeof(addr), url) < 0) return; if(rfork(RFPROC|RFMEM)) return; if(debug) fprint(2, "udptracker %s\n", addr); event = 1; for(;;){ alarm(30000); if((fd = dial(addr, 0, 0, 0)) < 0) goto Sleep; /* connect */ transid = rand(); n = pack(buf, sizeof(buf), "vll", 0x41727101980LL, 0, transid); if(write(fd, buf, n) != n) goto Sleep; for(;;){ if((n = read(fd, buf, sizeof(buf))) <= 0) goto Sleep; if(unpack(buf, n, "llv", &a, &i, &connid) < 0) continue; if(a == 0 && i == transid) break; } alarm(0); /* announce */ transid = rand(); lock(&stats); n = pack(buf, sizeof(buf), "vll**vvvl____llw", connid, 1, transid, sizeof(infohash), infohash, sizeof(peerid), peerid, stats.down, stats.left, stats.up, event, 0, -1, port); unlock(&stats); interval = 0; alarm(30000); if(write(fd, buf, n) != n) goto Sleep; for(;;){ if((n = read(fd, buf, sizeof(buf))) <= 0) goto Sleep; if((m = unpack(buf, n, "lll________", &a, &i, &interval)) < 0) continue; if(a == 1 && i == transid){ clients4(buf+m, n - m); break; } } event = 0; Sleep: alarm(0); if(fd >= 0) close(fd); if(interval < 10 | interval > 60*60) interval = 2*60; sleep(interval * 1000 + nrand(5000)); } } void tracker(char *url) { static Dict *trackers; static QLock trackerslk; Dict *d; int n; if(url == nil) return; qlock(&trackerslk); if(dlook(trackers, url)){ qunlock(&trackerslk); return; } n = strlen(url); d = mallocz(sizeof(*d) + n+1, 1); strcpy(d->str, url); d->len = n; d->typ = 'd'; d->val = d; d->next = trackers; trackers = d; url = d->str; qunlock(&trackerslk); if(!cistrncmp(url, "udp:", 4)) udptracker(url); else webtracker(url); } int Hfmt(Fmt *f) { uchar *s, *e; s = va_arg(f->args, uchar*); if(f->flags & FmtPrec) e = s + f->prec; else e = s + strlen((char*)s); for(; s < e; s++) if(fmtprint(f, *s && ((*s >= '0' && *s <= '9') || (*s >= 'a' && *s <= 'z') || (*s >= 'A' && *s <= 'Z') || strchr(".-_~", *s)) ? "%c" : "%%%.2x", *s) < 0) return -1; return 0; } int mktorrent(int fd, Dict *alist, Dict *wlist) { uchar *b, h[20]; Dir *d; int n; if((d = dirfstat(fd)) == nil) return -1; if(d->qid.type & QTDIR){ free(d); werrstr("file is a directory"); return -1; } if(d->length == 0){ free(d); werrstr("empty file"); return -1; } for(blocksize = 256*1024;;blocksize<<=1){ npieces = (d->length + blocksize-1) / blocksize; if(npieces <= 8*1024 || blocksize >= 2*1024*1024) break; } /* * keys in dictionaries have to be ordered alphabetically */ print("d8:announce%ld:%s", strlen(alist->str), alist->str); if(alist->next){ print("13:announce-listl"); print("l%ld:%se", strlen(alist->str), alist->str); for(alist = alist->next; alist; alist = alist->next) print("l%ld:%se", strlen(alist->str), alist->str); print("e"); } print("4:infod"); print("6:lengthi%llde", d->length); print("4:name%ld:%s", strlen(d->name), d->name); print("12:piece lengthi%de", blocksize); print("6:pieces%d:", npieces*sizeof(h)); free(d); b = malloc(blocksize); while((n = readn(fd, b, blocksize)) > 0){ sha1(b, n, h, nil); if(write(1, h, sizeof(h)) != sizeof(h)){ free(b); return -1; } npieces--; } if(npieces){ werrstr("read failed: %r"); return -1; } free(b); print("e"); if(wlist){ if(wlist->next){ print("8:url-listl"); for(; wlist; wlist = wlist->next) print("%ld:%s", strlen(wlist->str), wlist->str); print("e"); } else print("8:url-list%ld:%s", strlen(wlist->str), wlist->str); } print("e"); return 0; } int mkdirs(char *s) { char *p; int f; if(access(s, AEXIST) == 0) return 0; for(p=strchr(s+1, '/'); p; p=strchr(p+1, '/')){ *p = 0; if(access(s, AEXIST)){ if((f = create(s, OREAD, DMDIR | 0777)) < 0){ *p = '/'; return -1; } close(f); } *p = '/'; } return 0; } char* fixnamedup(char *s) { int n, l; char *d; Rune r; n = 0; d = strdup(s); l = strlen(d); while(*s){ s += chartorune(&r, s); if(r == ' ') r = 0xa0; if((n + runelen(r)) >= l){ l += 64; d = realloc(d, l); } n += runetochar(d + n, &r); } d[n] = 0; return cleanname(d); } int catch(void *, char *msg) { if(strstr(msg, "alarm")) return 1; postnote(PNGROUP, killgroup, "kill"); return 0; } void usage(void) { fprint(2, "usage: %s [ -vsdpc ] [ -m mtpt ] [ -t tracker-url ] " "[ -w webseed-url ] [ -i peerid ] [ -A useragent ] [ file ]\n", argv0); exits("usage"); } Dict* scons(char *s, Dict *t) { Dict *l; if(s == nil) return t; for(l = t; l; l = l->next) if(strcmp(l->str, s) == 0) return t; l = mallocz(sizeof(*l) + strlen(s)+1, 1); l->next = t; strcpy(l->str, s); return l; } void main(int argc, char *argv[]) { int sflag, pflag, vflag, cflag, fd, i, n; Dict *alist, *wlist, *info, *torrent, *d, *l; char *p, *s, *e; File **fp, *f; vlong len; fmtinstall('H', Hfmt); alist = wlist = nil; sflag = pflag = vflag = cflag = 0; ARGBEGIN { case 'm': mntweb = EARGF(usage()); break; case 't': alist = scons(EARGF(usage()), alist); break; case 'w': wlist = scons(EARGF(usage()), wlist); break; case 's': sflag = 1; break; case 'p': pflag = 1; break; case 'v': vflag = 1; break; case 'c': cflag = 1; break; case 'd': debug++; break; case 'i': strncpy((char*)peerid, EARGF(usage()), sizeof(peerid)); break; case 'A': useragent = EARGF(usage()); break; default: usage(); } ARGEND; if((s = getenv("NPROC")) != 0){ if((nproc = atoi(s)) <= 0) nproc = 1; free(s); } fd = 0; if(*argv) if((fd = open(*argv, OREAD)) < 0) sysfatal("open: %r"); if(cflag){ if(alist == nil) alist = scons(deftrack, alist); if(mktorrent(fd, alist, wlist) < 0) sysfatal("%r"); exits(0); } if((n = readall(fd, &p)) <= 0) sysfatal("read torrent: %r"); bparse(p, p+n, &torrent); alist = scons(dstr(dlook(torrent, "announce")), alist); for(d = dlook(torrent, "announce-list"); d && d->typ == 'l'; d = d->next) for(l = d->val; l && l->typ == 'l'; l = l->next) alist = scons(dstr(l->val), alist); if(d = dlook(torrent, "url-list")){ if(d->typ == 's') wlist = scons(dstr(d->val), wlist); else for(l = d; l && l->typ == 'l'; l = l->next) wlist = scons(dstr(l->val), wlist); /* make wlist into a ring */ for(l = wlist; l && l->next; l = l->next) ; if(l) l->next = wlist; } if(alist == nil && wlist == nil) sysfatal("no trackers or webseeds in torrent"); if((d = info = dlook(torrent, "info")) == nil) sysfatal("no meta info in torrent"); for(s = e = d->start; d && d->typ == 'd'; d = d->next) e = d->end; sha1((uchar*)s, e - s, (uchar*)infohash, nil); free(p); fp = &files; if(d = dlook(info, "files")){ for(; d && d->typ == 'l'; d = d->next){ Dict *di; if((s = dstr(dlook(d->val, "length"))) == nil) continue; f = mallocz(sizeof(*f), 1); f->len = atoll(s); f->name = dstr(dlook(info, "name")); for(di = dlook(d->val, "path"); di && di->typ == 'l'; di = di->next) if(s = dstr(di->val)) f->name = f->name ? smprint("%s/%s", f->name, s) : s; *fp = f; fp = &f->next; } } else if(s = dstr(dlook(info, "length"))){ f = mallocz(sizeof(*f), 1); f->len = atoll(s); f->name = dstr(dlook(info, "name")); *fp = f; } len = 0; for(f = files; f; f = f->next){ if(f->name == nil || f->len <= 0) sysfatal("bogus file entry in meta info"); s = fixnamedup(f->name); if(vflag) fprint(pflag ? 2 : 1, "%s\n", s); if((f->fd = open(s, ORDWR)) < 0){ if(mkdirs(s) < 0) sysfatal("mkdirs: %r"); if((f->fd = create(s, ORDWR, 0666)) < 0) sysfatal("create: %r"); } f->off = len; len += f->len; } if(len <= 0) sysfatal("no files in torrent"); if((s = dstr(dlook(info, "piece length"))) == nil) sysfatal("missing piece length in meta info"); if((blocksize = atoi(s)) <= 0) sysfatal("bogus piece length in meta info"); d = dlook(info, "pieces"); if(d == nil || d->typ != 's' || d->len <= 0 || d->len % 20) sysfatal("bad or no pices in meta info"); npieces = d->len / 20; pieces = mallocz(sizeof(Piece) * npieces, 1); nhavemap = (npieces+7) / 8; havemap = mallocz(nhavemap, 1); for(i = 0; i<npieces; i++){ pieces[i].hash = (uchar*)d->str + i*20; if(len < blocksize) pieces[i].len = len; else pieces[i].len = blocksize; len -= pieces[i].len; stats.left += pieces[i].len; } if(len) sysfatal("pieces do not match file length"); for(i=0; i<nproc; i++){ switch(rfork(RFPROC|RFMEM)){ case -1: sysfatal("fork: %r"); case 0: for(; i<npieces; i+=nproc) havepiece(i); exits(0); } } while(waitpid() >= 0) ; srand(time(0)); atnotify(catch, 1); switch(i = rfork(RFPROC|RFMEM|RFNOTEG)){ case -1: sysfatal("fork: %r"); case 0: if(peerid[0] == 0) strncpy((char*)peerid, "-NF9001-", 9); for(i=sizeof(peerid)-1; i >= 0 && peerid[i] == 0; i--) peerid[i] = nrand(10)+'0'; server(); for(; alist; alist = alist->next) tracker(alist->str); for(f = files, l = wlist; f && l; f = f->next, l = l->next) webseed(l, f); while(waitpid() != -1) ; break; default: killgroup = i; do { sleep(1000); if(pflag) print("%d %d\n", nhavepieces, npieces); } while(!finished() || sflag); } postnote(PNGROUP, killgroup, "kill"); exits(0); }