ref: 5e81cc48bdb00a3e7ae3334728659b8f014248da
dir: /sys/src/libhttpd/parsereq.c/
#include <u.h> #include <libc.h> #include <bin.h> #include <httpd.h> typedef struct Strings Strings; struct Strings { char *s1; char *s2; }; static char* abspath(HConnect *cc, char *origpath, char *curdir); static int getc(HConnect*); static char* getword(HConnect*); static Strings parseuri(HConnect *c, char*); static Strings stripsearch(char*); /* * parse the next request line * returns: * 1 ok * 0 eof * -1 error */ int hparsereq(HConnect *c, int timeout) { Strings ss; char *vs, *v, *search, *uri, *origuri, *extra; if(c->bin != nil){ hfail(c, HInternal); return -1; } /* * serve requests until a magic request. * later requests have to come quickly. * only works for http/1.1 or later. */ if(timeout) alarm(timeout); if(hgethead(c, 0) < 0) return -1; if(timeout) alarm(0); c->reqtime = time(nil); c->req.meth = getword(c); if(c->req.meth == nil){ hfail(c, HSyntax); return -1; } uri = getword(c); if(uri == nil || strlen(uri) == 0){ hfail(c, HSyntax); return -1; } v = getword(c); if(v == nil){ if(strcmp(c->req.meth, "GET") != 0){ hfail(c, HUnimp, c->req.meth); return -1; } c->req.vermaj = 0; c->req.vermin = 9; }else{ vs = v; if(strncmp(vs, "HTTP/", 5) != 0){ hfail(c, HUnkVers, vs); return -1; } vs += 5; c->req.vermaj = strtoul(vs, &vs, 10); if(*vs != '.' || c->req.vermaj != 1){ hfail(c, HUnkVers, vs); return -1; } vs++; c->req.vermin = strtoul(vs, &vs, 10); if(*vs != '\0'){ hfail(c, HUnkVers, vs); return -1; } extra = getword(c); if(extra != nil){ hfail(c, HSyntax); return -1; } } /* * the fragment is not supposed to be sent * strip it 'cause some clients send it */ origuri = uri; uri = strchr(origuri, '#'); if(uri != nil) *uri = 0; /* * http/1.1 requires the server to accept absolute * or relative uri's. convert to relative with an absolute path */ if(http11(c)){ ss = parseuri(c, origuri); uri = ss.s1; c->req.urihost = ss.s2; if(uri == nil){ hfail(c, HBadReq, uri); return -1; } origuri = uri; } /* * munge uri for search, protection, and magic */ ss = stripsearch(origuri); origuri = ss.s1; search = ss.s2; uri = hurlunesc(c, origuri); uri = abspath(c, uri, "/"); if(uri == nil || uri[0] == '\0'){ hfail(c, HNotFound, "no object specified"); return -1; } c->req.uri = uri; c->req.search = search; if(search) c->req.searchpairs = hparsequery(c, hstrdup(c, search)); return 1; } static Strings parseuri(HConnect *c, char *uri) { Strings ss; char *urihost, *p; urihost = nil; ss.s1 = ss.s2 = nil; if(uri[0] != '/') if(cistrncmp(uri, "http://", 7) == 0) uri += 5; /* skip http: */ else if (cistrncmp(uri, "https://", 8) == 0) uri += 6; /* skip https: */ else return ss; /* * anything starting with // is a host name or number * hostnames consists of letters, digits, - and . * for now, just ignore any port given */ if(uri[0] == '/' && uri[1] == '/'){ urihost = uri + 2; p = strchr(urihost, '/'); if(p == nil) uri = hstrdup(c, "/"); else{ uri = hstrdup(c, p); *p = '\0'; } p = strchr(urihost, ':'); if(p != nil) *p = '\0'; } if(uri[0] != '/' || uri[1] == '/') return ss; ss.s1 = uri; ss.s2 = hlower(urihost); return ss; } static Strings stripsearch(char *uri) { Strings ss; char *search; search = strchr(uri, '?'); if(search != nil) *search++ = 0; ss.s1 = uri; ss.s2 = search; return ss; } /* * to circumscribe the accessible files we have to eliminate ..'s * and resolve all names from the root. */ static char* abspath(HConnect *cc, char *origpath, char *curdir) { char *p, *sp, *path, *work, *rpath; int len, n, c; if(curdir == nil) curdir = "/"; if(origpath == nil) origpath = ""; work = hstrdup(cc, origpath); path = work; /* * remove any really special characters */ for(sp = "`;|"; *sp; sp++){ p = strchr(path, *sp); if(p) *p = 0; } len = strlen(curdir) + strlen(path) + 2 + UTFmax; if(len < 10) len = 10; rpath = halloc(cc, len); if(*path == '/') rpath[0] = 0; else strcpy(rpath, curdir); n = strlen(rpath); while(path){ p = strchr(path, '/'); if(p) *p++ = 0; if(strcmp(path, "..") == 0){ while(n > 1){ n--; c = rpath[n]; rpath[n] = 0; if(c == '/') break; } }else if(strcmp(path, ".") == 0){ ; }else if(n == 1) n += snprint(rpath+n, len-n, "%s", path); else n += snprint(rpath+n, len-n, "/%s", path); path = p; } if(strncmp(rpath, "/bin/", 5) == 0) strcpy(rpath, "/"); return rpath; } static char* getword(HConnect *c) { char *buf; int ch, n; while((ch = getc(c)) == ' ' || ch == '\t' || ch == '\r') ; if(ch == '\n') return nil; n = 0; buf = halloc(c, 1); for(;;){ switch(ch){ case ' ': case '\t': case '\r': case '\n': buf[n] = '\0'; return hstrdup(c, buf); } if(n < HMaxWord-1){ buf = bingrow(&c->bin, buf, n, n + 1, 0); if(buf == nil) return nil; buf[n++] = ch; } ch = getc(c); } } static int getc(HConnect *c) { if(c->hpos < c->hstop) return *c->hpos++; return '\n'; }