ref: 56e71d5260182e2ac32e09767b7c9440048a1d2f
dir: /sys/src/cmd/ip/httpd/wikipost.c/
/* * Accept new wiki pages or modifications to existing ones via POST method. * * Talks to the server at /srv/wiki.service. */ #include <u.h> #include <libc.h> #include <bio.h> #include "httpd.h" #include "httpsrv.h" #define LOG "wiki" HConnect *hc; HSPriv *hp; /* go from possibly-latin1 url with escapes to utf */ char * _urlunesc(char *s) { char *t, *v, *u; Rune r; int c, n; /* unescape */ u = halloc(hc, strlen(s)+1); for(t = u; c = *s; s++){ if(c == '%'){ n = s[1]; if(n >= '0' && n <= '9') n = n - '0'; else if(n >= 'A' && n <= 'F') n = n - 'A' + 10; else if(n >= 'a' && n <= 'f') n = n - 'a' + 10; else break; r = n; n = s[2]; if(n >= '0' && n <= '9') n = n - '0'; else if(n >= 'A' && n <= 'F') n = n - 'A' + 10; else if(n >= 'a' && n <= 'f') n = n - 'a' + 10; else break; s += 2; c = r*16+n; } *t++ = c; } *t = 0; /* latin1 heuristic */ v = halloc(hc, UTFmax*strlen(u) + 1); s = u; t = v; while(*s){ /* in decoding error, assume latin1 */ if((n=chartorune(&r, s)) == 1 && r == Runeerror) r = *s; s += n; t += runetochar(t, &r); } *t = 0; return v; } enum { MaxLog = 100*1024, /* limit on length of any one log request */ }; static int dangerous(char *s) { if(s == nil) return 1; /* * This check shouldn't be needed; * filename folding is already supposed to have happened. * But I'm paranoid. */ while(s = strchr(s,'/')){ if(s[1]=='.' && s[2]=='.') return 1; s++; } return 0; } char* unhttp(char *s) { char *p, *r, *w; if(s == nil) return nil; for(p=s; *p; p++) if(*p=='+') *p = ' '; s = _urlunesc(s); for(r=w=s; *r; r++){ if(*r != '\r') *w++ = *r; } *w = '\0'; return s; } void mountwiki(HConnect *c, char *service) { char buf[128]; int fd; /* already in (possibly private) namespace? */ snprint(buf, sizeof buf, "/mnt/wiki.%s/new", service); if (access(buf, AREAD) == 0){ if (bind(buf, "/mnt/wiki", MREPL) < 0){ syslog(0, LOG, "%s bind /mnt/wiki failed: %r", hp->remotesys); hfail(c, HNotFound); exits("bind /mnt/wiki failed"); } return; } /* old way: public wikifs from /srv */ snprint(buf, sizeof buf, "/srv/wiki.%s", service); if((fd = open(buf, ORDWR)) < 0){ syslog(0, LOG, "%s open %s failed: %r", buf, hp->remotesys); hfail(c, HNotFound); exits("failed"); } if(mount(fd, -1, "/mnt/wiki", MREPL, "") < 0){ syslog(0, LOG, "%s mount /mnt/wiki failed: %r", hp->remotesys); hfail(c, HNotFound); exits("failed"); } close(fd); } char* dowiki(HConnect *c, char *title, char *author, char *comment, char *base, ulong version, char *text) { int fd, l, n, err; char *p, tmp[256]; int i; if((fd = open("/mnt/wiki/new", ORDWR)) < 0){ syslog(0, LOG, "%s open /mnt/wiki/new failed: %r", hp->remotesys); hfail(c, HNotFound); exits("failed"); } i=0; if((i++,fprint(fd, "%s\nD%lud\nA%s (%s)\n", title, version, author, hp->remotesys) < 0) || (i++,(comment && comment[0] && fprint(fd, "C%s\n", comment) < 0)) || (i++,fprint(fd, "\n") < 0) || (i++,(text[0] && write(fd, text, strlen(text)) != strlen(text)))){ syslog(0, LOG, "%s write failed %d %ld fd %d: %r", hp->remotesys, i, strlen(text), fd); hfail(c, HInternal); exits("failed"); } err = write(fd, "", 0); if(err) syslog(0, LOG, "%s commit failed %d: %r", hp->remotesys, err); seek(fd, 0, 0); if((n = read(fd, tmp, sizeof(tmp)-1)) <= 0){ if(n == 0) werrstr("short read"); syslog(0, LOG, "%s read failed: %r", hp->remotesys); hfail(c, HInternal); exits("failed"); } tmp[n] = '\0'; p = halloc(c, l=strlen(base)+strlen(tmp)+40); snprint(p, l, "%s/%s/%s.html", base, tmp, err ? "werror" : "index"); return p; } void main(int argc, char **argv) { Hio *hin, *hout; char *s, *t, *p, *f[10]; char *text, *title, *service, *base, *author, *comment, *url; int i, nf; ulong version; hc = init(argc, argv); hp = hc->private; if(dangerous(hc->req.uri)){ hfail(hc, HSyntax); exits("failed"); } if(hparseheaders(hc, HSTIMEOUT) < 0) exits("failed"); hout = &hc->hout; if(hc->head.expectother){ hfail(hc, HExpectFail, nil); exits("failed"); } if(hc->head.expectcont){ hprint(hout, "100 Continue\r\n"); hprint(hout, "\r\n"); hflush(hout); } s = nil; if(strcmp(hc->req.meth, "POST") == 0){ hin = hbodypush(&hc->hin, hc->head.contlen, hc->head.transenc); if(hin != nil){ alarm(15*60*1000); s = hreadbuf(hin, hin->pos); alarm(0); } if(s == nil){ hfail(hc, HBadReq, nil); exits("failed"); } t = strchr(s, '\n'); if(t != nil) *t = '\0'; }else{ hunallowed(hc, "GET, HEAD, PUT"); exits("unallowed"); } if(s == nil){ hfail(hc, HNoData, "wiki"); exits("failed"); } text = nil; title = nil; service = nil; author = "???"; comment = ""; base = nil; version = ~0; nf = getfields(s, f, nelem(f), 1, "&"); for(i=0; i<nf; i++){ if((p = strchr(f[i], '=')) == nil) continue; *p++ = '\0'; if(strcmp(f[i], "title")==0) title = p; else if(strcmp(f[i], "version")==0) version = strtoul(unhttp(p), 0, 10); else if(strcmp(f[i], "text")==0) text = p; else if(strcmp(f[i], "service")==0) service = p; else if(strcmp(f[i], "comment")==0) comment = p; else if(strcmp(f[i], "author")==0) author = p; else if(strcmp(f[i], "base")==0) base = p; } syslog(0, LOG, "%s post s %s t '%s' v %ld a %s c %s b %s t 0x%p", hp->remotesys, service, title, (long)version, author, comment, base, text); title = unhttp(title); comment = unhttp(comment); service = unhttp(service); text = unhttp(text); author = unhttp(author); base = unhttp(base); if(title==nil || version==~0 || text==nil || text[0]=='\0' || base == nil || service == nil || strchr(title, '\n') || strchr(comment, '\n') || dangerous(service) || strchr(service, '/') || strlen(service)>20){ syslog(0, LOG, "%s failed dangerous", hp->remotesys); hfail(hc, HSyntax); exits("failed"); } syslog(0, LOG, "%s post s %s t '%s' v %ld a %s c %s", hp->remotesys, service, title, (long)version, author, comment); if(strlen(text) > MaxLog) text[MaxLog] = '\0'; mountwiki(hc, service); url = dowiki(hc, title, author, comment, base, version, text); hredirected(hc, "303 See Other", url); exits(nil); }