diff options
Diffstat (limited to 'src/libhttpd/parsereq.c')
| -rw-r--r-- | src/libhttpd/parsereq.c | 296 |
1 files changed, 296 insertions, 0 deletions
diff --git a/src/libhttpd/parsereq.c b/src/libhttpd/parsereq.c new file mode 100644 index 00000000..19f03172 --- /dev/null +++ b/src/libhttpd/parsereq.c @@ -0,0 +1,296 @@ +#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 stripmagic(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. + */ + alarm(timeout); + if(!hgethead(c, 0)) + return 0; + 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; + + return 1; +} + +static Strings +parseuri(HConnect *c, char *uri) +{ + Strings ss; + char *urihost, *p; + + urihost = nil; + if(uri[0] != '/'){ + if(cistrncmp(uri, "http://", 7) != 0){ + ss.s1 = nil; + ss.s2 = nil; + return ss; + } + uri += 5; /* skip http: */ + } + + /* + * anything starting with // is a host name or number + * hostnames constists 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] == '/'){ + ss.s1 = nil; + ss.s2 = nil; + 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); + } + return nil; +} + +static int +getc(HConnect *c) +{ + if(c->hpos < c->hstop) + return *c->hpos++; + return '\n'; +} |