From a567f55ee47da94c337b232a3848d1c8bab254b2 Mon Sep 17 00:00:00 2001 From: Sebastian Hammer Date: Mon, 5 Feb 2007 16:15:41 +0000 Subject: [PATCH] Bug 769. Rewriting Location headers in proxy responses --- src/config.c | 12 ++++- src/config.h | 1 + src/http.c | 151 +++++++++++++++++++++++++++++++++++++++++++++++++-------- src/http.h | 5 +- src/pazpar2.c | 4 +- 5 files changed, 149 insertions(+), 24 deletions(-) diff --git a/src/config.c b/src/config.c index 3ceb427..80a3299 100644 --- a/src/config.c +++ b/src/config.c @@ -1,4 +1,4 @@ -/* $Id: config.c,v 1.13 2007-01-15 16:56:51 quinn Exp $ */ +/* $Id: config.c,v 1.14 2007-02-05 16:15:41 quinn Exp $ */ #include @@ -191,6 +191,7 @@ static struct conf_server *parse_server(xmlNode *node) r->port = 0; r->proxy_host = 0; r->proxy_port = 0; + r->myurl = 0; r->service = 0; r->next = 0; @@ -213,12 +214,21 @@ static struct conf_server *parse_server(xmlNode *node) { xmlChar *port = xmlGetProp(n, "port"); xmlChar *host = xmlGetProp(n, "host"); + xmlChar *myurl = xmlGetProp(n, "myurl"); if (port) r->proxy_port = atoi(port); if (host) r->proxy_host = nmem_strdup(nmem, host); + if (myurl) + r->myurl = nmem_strdup(nmem, myurl); + else + { + yaz_log(YLOG_FATAL, "Must specify @myurl for proxy"); + return 0; + } xmlFree(port); xmlFree(host); + xmlFree(myurl); } else if (!strcmp(n->name, "service")) { diff --git a/src/config.h b/src/config.h index 4dd83eb..6c7cab4 100644 --- a/src/config.h +++ b/src/config.h @@ -66,6 +66,7 @@ struct conf_server int port; char *proxy_host; int proxy_port; + char *myurl; struct conf_service *service; struct conf_server *next; }; diff --git a/src/http.c b/src/http.c index 3408089..291f0d9 100644 --- a/src/http.c +++ b/src/http.c @@ -1,5 +1,5 @@ /* - * $Id: http.c,v 1.9 2007-01-10 11:56:10 adam Exp $ + * $Id: http.c,v 1.10 2007-02-05 16:15:41 quinn Exp $ */ #include @@ -39,6 +39,7 @@ extern IOCHAN channel_list; static struct sockaddr_in *proxy_addr = 0; // If this is set, we proxy normal HTTP requests static char proxy_url[256] = ""; +static char myurl[256] = ""; static struct http_buf *http_buf_freelist = 0; static struct http_channel *http_channel_freelist = 0; @@ -210,12 +211,11 @@ char *http_argbyname(struct http_request *r, char *name) return 0; } -char *http_headerbyname(struct http_request *r, char *name) +char *http_headerbyname(struct http_header *h, char *name) { - struct http_header *p; - for (p = r->headers; p; p = p->next) - if (!strcmp(p->name, name)) - return p->value; + for (; h; h = h->next) + if (!strcmp(h->name, name)) + return h->value; return 0; } @@ -230,16 +230,10 @@ struct http_response *http_create_response(struct http_channel *c) return r; } -// Check if we have a complete request. Return 0 or length (including trailing newline) -// FIXME: Does not deal gracefully with requests carrying payload -// but this is kind of OK since we will reject anything other than an empty GET -static int request_check(struct http_buf *queue) +// Check if buf contains a package (minus payload) +static int package_check(const char *buf) { - char tmp[4096]; int len = 0; - char *buf = tmp; - - http_buf_peek(queue, tmp, 4096); while (*buf) // Check if we have a sequence of lines terminated by an empty line { char *b = strstr(buf, "\r\n"); @@ -255,6 +249,69 @@ static int request_check(struct http_buf *queue) return 0; } +// Check if we have a request. Return 0 or length +// (including trailing CRNL) FIXME: Does not deal gracefully with requests +// carrying payload but this is kind of OK since we will reject anything +// other than an empty GET +static int request_check(struct http_buf *queue) +{ + char tmp[4096]; + + http_buf_peek(queue, tmp, 4096); + return package_check(tmp); +} + +struct http_response *http_parse_response_buf(struct http_channel *c, const char *buf, int len) +{ + char tmp[4096]; + struct http_response *r = http_create_response(c); + char *p, *p2; + struct http_header **hp = &r->headers; + + if (len >= 4096) + return 0; + memcpy(tmp, buf, len); + for (p = tmp; *p && *p != ' '; p++) // Skip HTTP version + ; + p++; + // Response code + for (p2 = p; *p2 && *p2 != ' ' && p2 - p < 3; p2++) + r->code[p2 - p] = *p2; + if (!(p = strstr(tmp, "\r\n"))) + return 0; + p += 2; + while (*p) + { + if (!(p2 = strstr(p, "\r\n"))) + return 0; + if (p == p2) // End of headers + break; + else + { + struct http_header *h = *hp = nmem_malloc(c->nmem, sizeof(*h)); + char *value = strchr(p, ':'); + if (!value) + return 0; + *(value++) = '\0'; + h->name = nmem_strdup(c->nmem, p); + while (isspace(*value)) + value++; + if (value >= p2) // Empty header; + { + h->value = ""; + p = p2 + 2; + continue; + } + *p2 = '\0'; + h->value = nmem_strdup(c->nmem, value); + h->next = 0; + hp = &h->next; + p = p2 + 2; + } + } + return r; +} + struct http_request *http_parse_request(struct http_channel *c, struct http_buf **queue, int len) { @@ -373,7 +430,6 @@ struct http_request *http_parse_request(struct http_channel *c, struct http_buf return r; } - static struct http_buf *http_serialize_response(struct http_channel *c, struct http_response *r) { @@ -383,8 +439,12 @@ static struct http_buf *http_serialize_response(struct http_channel *c, wrbuf_printf(c->wrbuf, "HTTP/1.1 %s %s\r\n", r->code, r->msg); for (h = r->headers; h; h = h->next) wrbuf_printf(c->wrbuf, "%s: %s\r\n", h->name, h->value); - wrbuf_printf(c->wrbuf, "Content-length: %d\r\n", r->payload ? (int) strlen(r->payload) : 0); - wrbuf_printf(c->wrbuf, "Content-type: text/xml\r\n"); + if (r->payload) + { + wrbuf_printf(c->wrbuf, "Content-length: %d\r\n", r->payload ? + (int) strlen(r->payload) : 0); + wrbuf_printf(c->wrbuf, "Content-type: text/xml\r\n"); + } wrbuf_puts(c->wrbuf, "\r\n"); if (r->payload) @@ -470,6 +530,7 @@ static int http_proxy(struct http_request *rq) p = xmalloc(sizeof(struct http_proxy)); p->oqueue = 0; p->channel = c; + p->first_response = 1; c->proxy = p; // We will add EVENT_OUTPUT below p->iochan = iochan_create(sock, proxy_io, EVENT_INPUT); @@ -622,6 +683,23 @@ static void http_io(IOCHAN i, int event) } } +// If this hostname contains our proxy host as a prefix, replace with myurl +static char *sub_hostname(struct http_channel *c, char *buf) +{ + char tmp[1024]; + if (strlen(buf) > 1023) + return buf; + if (strncmp(buf, "http://", 7)) + return buf; + if (!strncmp(buf + 7, proxy_url, strlen(proxy_url))) + { + strcpy(tmp, myurl); + strcat(tmp, buf + strlen(proxy_url) + 7); + return nmem_strdup(c->nmem, tmp); + } + return buf; +} + // Handles I/O on a client connection to a backend web server (proxy mode) static void proxy_io(IOCHAN pi, int event) { @@ -657,7 +735,41 @@ static void proxy_io(IOCHAN pi, int event) { htbuf->buf[res] = '\0'; htbuf->len = res; - http_buf_enqueue(&hc->oqueue, htbuf); + int offset = 0; + if (pc->first_response) // Check if this is a redirect + { + int len; + if ((len = package_check(htbuf->buf))) + { + struct http_response *res = http_parse_response_buf(hc, htbuf->buf, len); + if (res) + { + struct http_header *h; + for (h = res->headers; h; h = h->next) + if (!strcmp(h->name, "Location")) + { + // We found a location header. Rewrite it. + struct http_buf *buf; + h->value = sub_hostname(hc, h->value); + buf = http_serialize_response(hc, res); + http_buf_enqueue(&hc->oqueue, buf); + offset = len; + break; + } + } + } + pc->first_response = 0; + } + // Write any remaining payload + if (htbuf->len - offset > 0) + { + if (offset > 0) + { + memmove(htbuf->buf, htbuf->buf + offset, htbuf->len - offset); + htbuf->len -= offset; + } + http_buf_enqueue(&hc->oqueue, htbuf + offset); + } } iochan_setflag(hc->iochan, EVENT_OUTPUT); break; @@ -834,12 +946,13 @@ void http_init(const char *addr) channel_list = c; } -void http_set_proxyaddr(char *host) +void http_set_proxyaddr(char *host, char *base_url) { char *p; int port; struct hostent *he; + strcpy(myurl, base_url); strcpy(proxy_url, host); p = strchr(host, ':'); yaz_log(YLOG_DEBUG, "Proxying for %s", host); diff --git a/src/http.h b/src/http.h index cd9ca38..1420f6e 100644 --- a/src/http.h +++ b/src/http.h @@ -35,6 +35,7 @@ struct http_proxy // attached to iochan for proxy connection IOCHAN iochan; struct http_channel *channel; struct http_buf *oqueue; + int first_response; }; struct http_header @@ -71,11 +72,11 @@ struct http_response char *payload; }; -void http_set_proxyaddr(char *url); +void http_set_proxyaddr(char *url, char *baseurl); void http_init(const char *addr); void http_addheader(struct http_response *r, const char *name, const char *value); char *http_argbyname(struct http_request *r, char *name); -char *http_headerbyname(struct http_request *r, char *name); +char *http_headerbyname(struct http_header *r, char *name); struct http_response *http_create_response(struct http_channel *c); void http_send_response(struct http_channel *c); diff --git a/src/pazpar2.c b/src/pazpar2.c index 9d10f84..adcf99d 100644 --- a/src/pazpar2.c +++ b/src/pazpar2.c @@ -1,4 +1,4 @@ -/* $Id: pazpar2.c,v 1.47 2007-02-04 21:48:21 quinn Exp $ */ +/* $Id: pazpar2.c,v 1.48 2007-02-05 16:15:41 quinn Exp $ */ #include #include @@ -1547,7 +1547,7 @@ static void start_proxy(void) else return; - http_set_proxyaddr(hp); + http_set_proxyaddr(hp, ser->myurl ? ser->myurl : ""); } int main(int argc, char **argv) -- 1.7.10.4