diff options
| -rw-r--r-- | lib/transfer.c | 465 | ||||
| -rw-r--r-- | lib/transfer.h | 3 |
2 files changed, 237 insertions, 231 deletions
diff --git a/lib/transfer.c b/lib/transfer.c index 8de1f9dc7..d33838ee8 100644 --- a/lib/transfer.c +++ b/lib/transfer.c @@ -1228,6 +1228,238 @@ CURLcode Curl_posttransfer(struct SessionHandle *data) return CURLE_OK; } +CURLcode Curl_follow(struct SessionHandle *data, + char *newurl) /* this 'newurl' is the Location: string, + and it must be malloc()ed before passed + here */ +{ + /* Location: redirect */ + char prot[16]; /* URL protocol string storage */ + char letter; /* used for a silly sscanf */ + + if (data->set.maxredirs && + (data->set.followlocation >= data->set.maxredirs)) { + failf(data,"Maximum (%d) redirects followed", data->set.maxredirs); + return CURLE_TOO_MANY_REDIRECTS; + } + + /* mark the next request as a followed location: */ + data->state.this_is_a_follow = TRUE; + + data->set.followlocation++; /* count location-followers */ + + if(data->set.http_auto_referer) { + /* We are asked to automatically set the previous URL as the + referer when we get the next URL. We pick the ->url field, + which may or may not be 100% correct */ + + if(data->change.referer_alloc) + /* If we already have an allocated referer, free this first */ + free(data->change.referer); + + data->change.referer = strdup(data->change.url); + data->change.referer_alloc = TRUE; /* yes, free this later */ + } + + if(2 != sscanf(newurl, "%15[^?&/:]://%c", prot, &letter)) { + /*** + *DANG* this is an RFC 2068 violation. The URL is supposed + to be absolute and this doesn't seem to be that! + *** + Instead, we have to TRY to append this new path to the old URL + to the right of the host part. Oh crap, this is doomed to cause + problems in the future... + */ + char *protsep; + char *pathsep; + char *newest; + + char *useurl = newurl; + + /* we must make our own copy of the URL to play with, as it may + point to read-only data */ + char *url_clone=strdup(data->change.url); + + if(!url_clone) + return CURLE_OUT_OF_MEMORY; /* skip out of this NOW */ + + /* protsep points to the start of the host name */ + protsep=strstr(url_clone, "//"); + if(!protsep) + protsep=url_clone; + else + protsep+=2; /* pass the slashes */ + + if('/' != newurl[0]) { + int level=0; + + /* First we need to find out if there's a ?-letter in the URL, + and cut it and the right-side of that off */ + pathsep = strrchr(protsep, '?'); + if(pathsep) + *pathsep=0; + + /* we have a relative path to append to the last slash if + there's one available */ + pathsep = strrchr(protsep, '/'); + if(pathsep) + *pathsep=0; + + /* Check if there's any slash after the host name, and if so, + remember that position instead */ + pathsep = strchr(protsep, '/'); + if(pathsep) + protsep = pathsep+1; + else + protsep = NULL; + + /* now deal with one "./" or any amount of "../" in the newurl + and act accordingly */ + + if((useurl[0] == '.') && (useurl[1] == '/')) + useurl+=2; /* just skip the "./" */ + + while((useurl[0] == '.') && + (useurl[1] == '.') && + (useurl[2] == '/')) { + level++; + useurl+=3; /* pass the "../" */ + } + + if(protsep) { + while(level--) { + /* cut off one more level from the right of the original URL */ + pathsep = strrchr(protsep, '/'); + if(pathsep) + *pathsep=0; + else { + *protsep=0; + break; + } + } + } + } + else { + /* We got a new absolute path for this server, cut off from the + first slash */ + pathsep = strchr(protsep, '/'); + if(pathsep) + *pathsep=0; + } + + newest=(char *)malloc( strlen(url_clone) + + 1 + /* possible slash */ + strlen(useurl) + 1/* zero byte */); + + if(!newest) + return CURLE_OUT_OF_MEMORY; /* go out from this */ + + sprintf(newest, "%s%s%s", url_clone, + (('/' == useurl[0]) || !*protsep)?"":"/", + useurl); + free(newurl); /* newurl is the allocated pointer */ + free(url_clone); + newurl = newest; + } + else + /* This is an absolute URL, don't allow the custom port number */ + data->state.allow_port = FALSE; + + if(data->change.url_alloc) + free(data->change.url); + else + data->change.url_alloc = TRUE; /* the URL is allocated */ + + /* TBD: set the URL with curl_setopt() */ + data->change.url = newurl; + newurl = NULL; /* don't free! */ + + infof(data, "Follows Location: to new URL: '%s'\n", data->change.url); + + /* + * We get here when the HTTP code is 300-399. We need to perform + * differently based on exactly what return code there was. + * Discussed on the curl mailing list and posted about on the 26th + * of January 2001. + */ + switch(data->info.httpcode) { + case 300: /* Multiple Choices */ + case 306: /* Not used */ + case 307: /* Temporary Redirect */ + default: /* for all unknown ones */ + /* These are explicitly mention since I've checked RFC2616 and they + * seem to be OK to POST to. + */ + break; + case 301: /* Moved Permanently */ + /* (quote from RFC2616, section 10.3.2): + * + * Note: When automatically redirecting a POST request after + * receiving a 301 status code, some existing HTTP/1.0 user agents + * will erroneously change it into a GET request. + * + * ---- + * Warning: Because most of importants user agents do this clear + * RFC2616 violation, many webservers expect this misbehavior. So + * these servers often answers to a POST request with an error page. + * To be sure that libcurl gets the page that most user agents + * would get, libcurl has to force GET: + */ + if( data->set.httpreq == HTTPREQ_POST + || data->set.httpreq == HTTPREQ_POST_FORM) { + infof(data, + "Violate RFC 2616/10.3.2 and switch from POST to GET\n"); + data->set.httpreq = HTTPREQ_GET; + } + break; + case 302: /* Found */ + /* (From 10.3.3) + + Note: RFC 1945 and RFC 2068 specify that the client is not allowed + to change the method on the redirected request. However, most + existing user agent implementations treat 302 as if it were a 303 + response, performing a GET on the Location field-value regardless + of the original request method. The status codes 303 and 307 have + been added for servers that wish to make unambiguously clear which + kind of reaction is expected of the client. + + (From 10.3.4) + + Note: Many pre-HTTP/1.1 user agents do not understand the 303 + status. When interoperability with such clients is a concern, the + 302 status code may be used instead, since most user agents react + to a 302 response as described here for 303. + */ + case 303: /* See Other */ + /* Disable both types of POSTs, since doing a second POST when + * following isn't what anyone would want! */ + if(data->set.httpreq != HTTPREQ_GET) { + data->set.httpreq = HTTPREQ_GET; /* enforce GET request */ + infof(data, "Disables POST, goes with %s\n", + data->set.no_body?"HEAD":"GET"); + } + break; + case 304: /* Not Modified */ + /* 304 means we did a conditional request and it was "Not modified". + * We shouldn't get any Location: header in this response! + */ + break; + case 305: /* Use Proxy */ + /* (quote from RFC2616, section 10.3.6): + * "The requested resource MUST be accessed through the proxy given + * by the Location field. The Location field gives the URI of the + * proxy. The recipient is expected to repeat this single request + * via the proxy. 305 responses MUST only be generated by origin + * servers." + */ + break; + } + Curl_pgrsTime(data, TIMER_REDIRECT); + Curl_pgrsResetTimes(data); + + return CURLE_OK; +} + CURLcode Curl_perform(struct SessionHandle *data) { CURLcode res; @@ -1299,236 +1531,11 @@ CURLcode Curl_perform(struct SessionHandle *data) */ if((res == CURLE_OK) && newurl) { - /* Location: redirect - - This is assumed to happen for HTTP(S) only! - */ - char prot[16]; /* URL protocol string storage */ - char letter; /* used for a silly sscanf */ - - if (data->set.maxredirs && (data->set.followlocation >= data->set.maxredirs)) { - failf(data,"Maximum (%d) redirects followed", data->set.maxredirs); - res=CURLE_TOO_MANY_REDIRECTS; - break; - } - - /* mark the next request as a followed location: */ - data->state.this_is_a_follow = TRUE; - - data->set.followlocation++; /* count location-followers */ - - if(data->set.http_auto_referer) { - /* We are asked to automatically set the previous URL as the - referer when we get the next URL. We pick the ->url field, - which may or may not be 100% correct */ - - if(data->change.referer_alloc) - /* If we already have an allocated referer, free this first */ - free(data->change.referer); - - data->change.referer = strdup(data->change.url); - data->change.referer_alloc = TRUE; /* yes, free this later */ - } - - if(2 != sscanf(newurl, "%15[^?&/:]://%c", prot, &letter)) { - /*** - *DANG* this is an RFC 2068 violation. The URL is supposed - to be absolute and this doesn't seem to be that! - *** - Instead, we have to TRY to append this new path to the old URL - to the right of the host part. Oh crap, this is doomed to cause - problems in the future... - */ - char *protsep; - char *pathsep; - char *newest; - - char *useurl = newurl; - - /* we must make our own copy of the URL to play with, as it may - point to read-only data */ - char *url_clone=strdup(data->change.url); - - if(!url_clone) { - res = CURLE_OUT_OF_MEMORY; - break; /* skip out of this loop NOW */ - } - - /* protsep points to the start of the host name */ - protsep=strstr(url_clone, "//"); - if(!protsep) - protsep=url_clone; - else - protsep+=2; /* pass the slashes */ - - if('/' != newurl[0]) { - int level=0; - - /* First we need to find out if there's a ?-letter in the URL, - and cut it and the right-side of that off */ - pathsep = strrchr(protsep, '?'); - if(pathsep) - *pathsep=0; - - /* we have a relative path to append to the last slash if - there's one available */ - pathsep = strrchr(protsep, '/'); - if(pathsep) - *pathsep=0; - - /* Check if there's any slash after the host name, and if so, - remember that position instead */ - pathsep = strchr(protsep, '/'); - if(pathsep) - protsep = pathsep+1; - else - protsep = NULL; - - /* now deal with one "./" or any amount of "../" in the newurl - and act accordingly */ - - if((useurl[0] == '.') && (useurl[1] == '/')) - useurl+=2; /* just skip the "./" */ - - while((useurl[0] == '.') && - (useurl[1] == '.') && - (useurl[2] == '/')) { - level++; - useurl+=3; /* pass the "../" */ - } - - if(protsep) { - while(level--) { - /* cut off one more level from the right of the original URL */ - pathsep = strrchr(protsep, '/'); - if(pathsep) - *pathsep=0; - else { - *protsep=0; - break; - } - } - } - } - else { - /* We got a new absolute path for this server, cut off from the - first slash */ - pathsep = strchr(protsep, '/'); - if(pathsep) - *pathsep=0; - } - - newest=(char *)malloc( strlen(url_clone) + - 1 + /* possible slash */ - strlen(useurl) + 1/* zero byte */); - - if(!newest) { - res = CURLE_OUT_OF_MEMORY; - break; /* go go go out from this loop */ - } - sprintf(newest, "%s%s%s", url_clone, - (('/' == useurl[0]) || !*protsep)?"":"/", - useurl); - free(newurl); /* newurl is the allocated pointer */ - free(url_clone); - newurl = newest; - } - else - /* This is an absolute URL, don't allow the custom port number */ - data->state.allow_port = FALSE; - - if(data->change.url_alloc) - free(data->change.url); - else - data->change.url_alloc = TRUE; /* the URL is allocated */ - - /* TBD: set the URL with curl_setopt() */ - data->change.url = newurl; - newurl = NULL; /* don't free! */ - - infof(data, "Follows Location: to new URL: '%s'\n", data->change.url); - - /* - * We get here when the HTTP code is 300-399. We need to perform - * differently based on exactly what return code there was. - * Discussed on the curl mailing list and posted about on the 26th - * of January 2001. - */ - switch(data->info.httpcode) { - case 300: /* Multiple Choices */ - case 306: /* Not used */ - case 307: /* Temporary Redirect */ - default: /* for all unknown ones */ - /* These are explicitly mention since I've checked RFC2616 and they - * seem to be OK to POST to. - */ - break; - case 301: /* Moved Permanently */ - /* (quote from RFC2616, section 10.3.2): - * - * Note: When automatically redirecting a POST request after - * receiving a 301 status code, some existing HTTP/1.0 user agents - * will erroneously change it into a GET request. - * - * ---- - * Warning: Because most of importants user agents do this clear - * RFC2616 violation, many webservers expect this misbehavior. So - * these servers often answers to a POST request with an error page. - * To be sure that libcurl gets the page that most user agents - * would get, libcurl has to force GET: - */ - if( data->set.httpreq == HTTPREQ_POST - || data->set.httpreq == HTTPREQ_POST_FORM) { - infof(data, - "Violate RFC 2616/10.3.2 and switch from POST to GET\n"); - data->set.httpreq = HTTPREQ_GET; - } - break; - case 302: /* Found */ - /* (From 10.3.3) - - Note: RFC 1945 and RFC 2068 specify that the client is not allowed - to change the method on the redirected request. However, most - existing user agent implementations treat 302 as if it were a 303 - response, performing a GET on the Location field-value regardless - of the original request method. The status codes 303 and 307 have - been added for servers that wish to make unambiguously clear which - kind of reaction is expected of the client. - - (From 10.3.4) - - Note: Many pre-HTTP/1.1 user agents do not understand the 303 - status. When interoperability with such clients is a concern, the - 302 status code may be used instead, since most user agents react - to a 302 response as described here for 303. - */ - case 303: /* See Other */ - /* Disable both types of POSTs, since doing a second POST when - * following isn't what anyone would want! */ - if(data->set.httpreq != HTTPREQ_GET) { - data->set.httpreq = HTTPREQ_GET; /* enforce GET request */ - infof(data, "Disables POST, goes with %s\n", - data->set.no_body?"HEAD":"GET"); - } - break; - case 304: /* Not Modified */ - /* 304 means we did a conditional request and it was "Not modified". - * We shouldn't get any Location: header in this response! - */ - break; - case 305: /* Use Proxy */ - /* (quote from RFC2616, section 10.3.6): - * "The requested resource MUST be accessed through the proxy given - * by the Location field. The Location field gives the URI of the - * proxy. The recipient is expected to repeat this single request - * via the proxy. 305 responses MUST only be generated by origin - * servers." - */ - break; + res = Curl_follow(data, newurl); + if(CURLE_OK == res) { + newurl = NULL; + continue; } - Curl_pgrsTime(data, TIMER_REDIRECT); - Curl_pgrsResetTimes(data); - continue; } } break; /* it only reaches here when this shouldn't loop */ diff --git a/lib/transfer.h b/lib/transfer.h index cdcbf0f71..c2c2fdeb7 100644 --- a/lib/transfer.h +++ b/lib/transfer.h @@ -23,10 +23,9 @@ * $Id$ ***************************************************************************/ CURLcode Curl_perform(struct SessionHandle *data); - CURLcode Curl_pretransfer(struct SessionHandle *data); CURLcode Curl_posttransfer(struct SessionHandle *data); - +CURLcode Curl_follow(struct SessionHandle *data, char *newurl); CURLcode Curl_readwrite(struct connectdata *conn, bool *done); void Curl_single_fdset(struct connectdata *conn, fd_set *read_fd_set, |