diff options
| -rw-r--r-- | lib/url.c | 121 |
1 files changed, 78 insertions, 43 deletions
@@ -2039,6 +2039,14 @@ static CURLcode parseurlandfillconn(struct Curl_easy *data, ('A' <= str[0] && str[0] <= 'Z')) && \ (str[1] == ':')) + /* MSDOS/Windows style drive prefix, optionally with + * a '|' instead of ':', followed by a slash or NUL */ +#define STARTS_WITH_URL_DRIVE_PREFIX(str) \ + ((('a' <= (str)[0] && (str)[0] <= 'z') || \ + ('A' <= (str)[0] && (str)[0] <= 'Z')) && \ + ((str)[1] == ':' || (str)[1] == '|') && \ + ((str)[2] == '/' || (str)[2] == 0)) + /* Don't mistake a drive letter for a scheme if the default protocol is file. curld --proto-default file c:/foo/bar.txt */ if(STARTS_WITH_DRIVE_PREFIX(data->change.url) && @@ -2071,63 +2079,90 @@ static CURLcode parseurlandfillconn(struct Curl_easy *data, return CURLE_URL_MALFORMAT; } - if(url_has_scheme && path[0] == '/' && path[1] == '/') { - /* Allow omitted hostname (e.g. file:/<path>). This is not strictly - * speaking a valid file: URL by RFC 1738, but treating file:/<path> as - * file://localhost/<path> is similar to how other schemes treat missing - * hostnames. See RFC 1808. */ - - /* This cannot be done with strcpy() in a portable manner, since the - memory areas overlap! */ - memmove(path, path + 2, strlen(path + 2) + 1); + if(url_has_scheme && path[0] == '/' && path[1] == '/' && + path[2] == '/' && path[3] == '/') { + /* This appears to be a UNC string (usually indicating a SMB share). + * We don't do SMB in file: URLs. (TODO?) + */ + failf(data, "SMB shares are not supported in file: URLs."); + return CURLE_URL_MALFORMAT; } - /* - * we deal with file://<host>/<path> differently since it supports no - * hostname other than "localhost" and "127.0.0.1", which is unique among - * the URL protocols specified in RFC 1738 + /* Extra handling URLs with an authority component (i.e. that start with + * "file://") + * + * We allow omitted hostname (e.g. file:/<path>) -- valid according to + * RFC 8089, but not the (current) WHAT-WG URL spec. */ - if(path[0] != '/' && !STARTS_WITH_DRIVE_PREFIX(path)) { - /* the URL includes a host name, it must match "localhost" or - "127.0.0.1" to be valid */ - char *ptr; - if(!checkprefix("localhost/", path) && - !checkprefix("127.0.0.1/", path)) { - failf(data, "Invalid file://hostname/, " - "expected localhost or 127.0.0.1 or none"); - return CURLE_URL_MALFORMAT; - } - ptr = &path[9]; /* now points to the slash after the host */ - - /* there was a host name and slash present - - RFC1738 (section 3.1, page 5) says: - - The rest of the locator consists of data specific to the scheme, - and is known as the "url-path". It supplies the details of how the - specified resource can be accessed. Note that the "/" between the - host (or port) and the url-path is NOT part of the url-path. + if(url_has_scheme && path[0] == '/' && path[1] == '/') { + /* swallow the two slashes */ + char *ptr = &path[2]; - As most agents use file://localhost/foo to get '/foo' although the - slash preceding foo is a separator and not a slash for the path, - a URL as file://localhost//foo must be valid as well, to refer to - the same file with an absolute path. - */ + /* + * According to RFC 8089, a file: URL can be reliably dereferenced if: + * + * o it has no/blank hostname, or + * + * o the hostname matches "localhost" (case-insensitively), or + * + * o the hostname is a FQDN that resolves to this machine. + * + * For brevity, we only consider URLs with empty, "localhost", or + * "127.0.0.1" hostnames as local. + * + * Additionally, there is an exception for URLs with a Windows drive + * letter in the authority (which was accidentally omitted from RFC 8089 + * Appendix E, but believe me, it was meant to be there. --MK) + */ + if(ptr[0] != '/' && !STARTS_WITH_URL_DRIVE_PREFIX(ptr)) { + /* the URL includes a host name, it must match "localhost" or + "127.0.0.1" to be valid */ + if(!checkprefix("localhost/", ptr) && + !checkprefix("127.0.0.1/", ptr)) { + failf(data, "Invalid file://hostname/, " + "expected localhost or 127.0.0.1 or none"); + return CURLE_URL_MALFORMAT; + } + ptr += 9; /* now points to the slash after the host */ + } - if('/' == ptr[1]) - /* if there was two slashes, we skip the first one as that is then - used truly as a separator */ + /* + * RFC 8089, Appendix D, Section D.1, says: + * + * > In a POSIX file system, the root of the file system is represented + * > as a directory with a zero-length name, usually written as "/"; the + * > presence of this root in a file URI can be taken as given by the + * > initial slash in the "path-absolute" rule. + * + * i.e. the first slash is part of the path. + * + * However in RFC 1738 the "/" between the host (or port) and the + * URL-path was NOT part of the URL-path. Any agent that followed the + * older spec strictly, and wanted to refer to a file with an absolute + * path, would have included a second slash. So if there are two + * slashes, swallow one. + */ + if('/' == ptr[1]) /* note: the only way ptr[0]!='/' is if ptr[1]==':' */ ptr++; - /* This cannot be made with strcpy, as the memory chunks overlap! */ + /* This cannot be done with strcpy, as the memory chunks overlap! */ memmove(path, ptr, strlen(ptr) + 1); } #if !defined(MSDOS) && !defined(WIN32) && !defined(__CYGWIN__) - if(STARTS_WITH_DRIVE_PREFIX(path)) { + /* Don't allow Windows drive letters when not in Windows. + * This catches both "file:/c:" and "file:c:" */ + if(('/' == path[0] && STARTS_WITH_URL_DRIVE_PREFIX(&path[1])) || + STARTS_WITH_URL_DRIVE_PREFIX(path)) { failf(data, "File drive letters are only accepted in MSDOS/Windows."); return CURLE_URL_MALFORMAT; } +#else + /* If the path starts with a slash and a drive letter, ditch the slash */ + if('/' == path[0] && STARTS_WITH_URL_DRIVE_PREFIX(&path[1])) { + /* This cannot be done with strcpy, as the memory chunks overlap! */ + memmove(path, &path[1], strlen(&path[1]) + 1); + } #endif protop = "file"; /* protocol string */ |