Mercurial > hg > nginx-quic
view src/core/ngx_proxy_protocol.c @ 8895:457afc332c67
Stream: don't flush empty buffers created for read errors.
When we generate the last_buf buffer for an UDP upstream recv error, it does
not contain any data from the wire. ngx_stream_write_filter attempts to forward
it anyways, which is incorrect (e.g., UDP upstream ECONNREFUSED will be
translated to an empty packet).
This happens because we mark the buffer as both 'flush' and 'last_buf', and
ngx_stream_write_filter has special handling for flush with certain types of
connections (see d127837c714f, 32b0ba4855a6). The flags are meant to be
mutually exclusive, so the fix is to ensure that flush and last_buf are not set
at the same time.
Reproduction:
stream {
upstream unreachable {
server 127.0.0.1:8880;
}
server {
listen 127.0.0.1:8998 udp;
proxy_pass unreachable;
}
}
1 0.000000000 127.0.0.1 → 127.0.0.1 UDP 47 45588 → 8998 Len=5
2 0.000166300 127.0.0.1 → 127.0.0.1 UDP 47 51149 → 8880 Len=5
3 0.000172600 127.0.0.1 → 127.0.0.1 ICMP 75 Destination unreachable (Port
unreachable)
4 0.000202400 127.0.0.1 → 127.0.0.1 UDP 42 8998 → 45588 Len=0
Fixes d127837c714f.
author | Aleksei Bavshin <a.bavshin@f5.com> |
---|---|
date | Mon, 23 May 2022 11:29:44 -0700 |
parents | 89adf49fe76a |
children | 017fd847f4f7 |
line wrap: on
line source
/* * Copyright (C) Roman Arutyunyan * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #define NGX_PROXY_PROTOCOL_AF_INET 1 #define NGX_PROXY_PROTOCOL_AF_INET6 2 #define ngx_proxy_protocol_parse_uint16(p) ((p)[0] << 8 | (p)[1]) typedef struct { u_char signature[12]; u_char version_command; u_char family_transport; u_char len[2]; } ngx_proxy_protocol_header_t; typedef struct { u_char src_addr[4]; u_char dst_addr[4]; u_char src_port[2]; u_char dst_port[2]; } ngx_proxy_protocol_inet_addrs_t; typedef struct { u_char src_addr[16]; u_char dst_addr[16]; u_char src_port[2]; u_char dst_port[2]; } ngx_proxy_protocol_inet6_addrs_t; static u_char *ngx_proxy_protocol_read_addr(ngx_connection_t *c, u_char *p, u_char *last, ngx_str_t *addr); static u_char *ngx_proxy_protocol_read_port(u_char *p, u_char *last, in_port_t *port, u_char sep); static u_char *ngx_proxy_protocol_v2_read(ngx_connection_t *c, u_char *buf, u_char *last); u_char * ngx_proxy_protocol_read(ngx_connection_t *c, u_char *buf, u_char *last) { size_t len; u_char *p; ngx_proxy_protocol_t *pp; static const u_char signature[] = "\r\n\r\n\0\r\nQUIT\n"; p = buf; len = last - buf; if (len >= sizeof(ngx_proxy_protocol_header_t) && memcmp(p, signature, sizeof(signature) - 1) == 0) { return ngx_proxy_protocol_v2_read(c, buf, last); } if (len < 8 || ngx_strncmp(p, "PROXY ", 6) != 0) { goto invalid; } p += 6; len -= 6; if (len >= 7 && ngx_strncmp(p, "UNKNOWN", 7) == 0) { ngx_log_debug0(NGX_LOG_DEBUG_CORE, c->log, 0, "PROXY protocol unknown protocol"); p += 7; goto skip; } if (len < 5 || ngx_strncmp(p, "TCP", 3) != 0 || (p[3] != '4' && p[3] != '6') || p[4] != ' ') { goto invalid; } p += 5; pp = ngx_pcalloc(c->pool, sizeof(ngx_proxy_protocol_t)); if (pp == NULL) { return NULL; } p = ngx_proxy_protocol_read_addr(c, p, last, &pp->src_addr); if (p == NULL) { goto invalid; } p = ngx_proxy_protocol_read_addr(c, p, last, &pp->dst_addr); if (p == NULL) { goto invalid; } p = ngx_proxy_protocol_read_port(p, last, &pp->src_port, ' '); if (p == NULL) { goto invalid; } p = ngx_proxy_protocol_read_port(p, last, &pp->dst_port, CR); if (p == NULL) { goto invalid; } if (p == last) { goto invalid; } if (*p++ != LF) { goto invalid; } ngx_log_debug4(NGX_LOG_DEBUG_CORE, c->log, 0, "PROXY protocol src: %V %d, dst: %V %d", &pp->src_addr, pp->src_port, &pp->dst_addr, pp->dst_port); c->proxy_protocol = pp; return p; skip: for ( /* void */ ; p < last - 1; p++) { if (p[0] == CR && p[1] == LF) { return p + 2; } } invalid: ngx_log_error(NGX_LOG_ERR, c->log, 0, "broken header: \"%*s\"", (size_t) (last - buf), buf); return NULL; } static u_char * ngx_proxy_protocol_read_addr(ngx_connection_t *c, u_char *p, u_char *last, ngx_str_t *addr) { size_t len; u_char ch, *pos; pos = p; for ( ;; ) { if (p == last) { return NULL; } ch = *p++; if (ch == ' ') { break; } if (ch != ':' && ch != '.' && (ch < 'a' || ch > 'f') && (ch < 'A' || ch > 'F') && (ch < '0' || ch > '9')) { return NULL; } } len = p - pos - 1; addr->data = ngx_pnalloc(c->pool, len); if (addr->data == NULL) { return NULL; } ngx_memcpy(addr->data, pos, len); addr->len = len; return p; } static u_char * ngx_proxy_protocol_read_port(u_char *p, u_char *last, in_port_t *port, u_char sep) { size_t len; u_char *pos; ngx_int_t n; pos = p; for ( ;; ) { if (p == last) { return NULL; } if (*p++ == sep) { break; } } len = p - pos - 1; n = ngx_atoi(pos, len); if (n < 0 || n > 65535) { return NULL; } *port = (in_port_t) n; return p; } u_char * ngx_proxy_protocol_write(ngx_connection_t *c, u_char *buf, u_char *last) { ngx_uint_t port, lport; if (last - buf < NGX_PROXY_PROTOCOL_MAX_HEADER) { return NULL; } if (ngx_connection_local_sockaddr(c, NULL, 0) != NGX_OK) { return NULL; } switch (c->sockaddr->sa_family) { case AF_INET: buf = ngx_cpymem(buf, "PROXY TCP4 ", sizeof("PROXY TCP4 ") - 1); break; #if (NGX_HAVE_INET6) case AF_INET6: buf = ngx_cpymem(buf, "PROXY TCP6 ", sizeof("PROXY TCP6 ") - 1); break; #endif default: return ngx_cpymem(buf, "PROXY UNKNOWN" CRLF, sizeof("PROXY UNKNOWN" CRLF) - 1); } buf += ngx_sock_ntop(c->sockaddr, c->socklen, buf, last - buf, 0); *buf++ = ' '; buf += ngx_sock_ntop(c->local_sockaddr, c->local_socklen, buf, last - buf, 0); port = ngx_inet_get_port(c->sockaddr); lport = ngx_inet_get_port(c->local_sockaddr); return ngx_slprintf(buf, last, " %ui %ui" CRLF, port, lport); } static u_char * ngx_proxy_protocol_v2_read(ngx_connection_t *c, u_char *buf, u_char *last) { u_char *end; size_t len; socklen_t socklen; ngx_uint_t version, command, family, transport; ngx_sockaddr_t src_sockaddr, dst_sockaddr; ngx_proxy_protocol_t *pp; ngx_proxy_protocol_header_t *header; ngx_proxy_protocol_inet_addrs_t *in; #if (NGX_HAVE_INET6) ngx_proxy_protocol_inet6_addrs_t *in6; #endif header = (ngx_proxy_protocol_header_t *) buf; buf += sizeof(ngx_proxy_protocol_header_t); version = header->version_command >> 4; if (version != 2) { ngx_log_error(NGX_LOG_ERR, c->log, 0, "unknown PROXY protocol version: %ui", version); return NULL; } len = ngx_proxy_protocol_parse_uint16(header->len); if ((size_t) (last - buf) < len) { ngx_log_error(NGX_LOG_ERR, c->log, 0, "header is too large"); return NULL; } end = buf + len; command = header->version_command & 0x0f; /* only PROXY is supported */ if (command != 1) { ngx_log_debug1(NGX_LOG_DEBUG_CORE, c->log, 0, "PROXY protocol v2 unsupported command %ui", command); return end; } transport = header->family_transport & 0x0f; /* only STREAM is supported */ if (transport != 1) { ngx_log_debug1(NGX_LOG_DEBUG_CORE, c->log, 0, "PROXY protocol v2 unsupported transport %ui", transport); return end; } pp = ngx_pcalloc(c->pool, sizeof(ngx_proxy_protocol_t)); if (pp == NULL) { return NULL; } family = header->family_transport >> 4; switch (family) { case NGX_PROXY_PROTOCOL_AF_INET: if ((size_t) (end - buf) < sizeof(ngx_proxy_protocol_inet_addrs_t)) { return NULL; } in = (ngx_proxy_protocol_inet_addrs_t *) buf; src_sockaddr.sockaddr_in.sin_family = AF_INET; src_sockaddr.sockaddr_in.sin_port = 0; memcpy(&src_sockaddr.sockaddr_in.sin_addr, in->src_addr, 4); dst_sockaddr.sockaddr_in.sin_family = AF_INET; dst_sockaddr.sockaddr_in.sin_port = 0; memcpy(&dst_sockaddr.sockaddr_in.sin_addr, in->dst_addr, 4); pp->src_port = ngx_proxy_protocol_parse_uint16(in->src_port); pp->dst_port = ngx_proxy_protocol_parse_uint16(in->dst_port); socklen = sizeof(struct sockaddr_in); buf += sizeof(ngx_proxy_protocol_inet_addrs_t); break; #if (NGX_HAVE_INET6) case NGX_PROXY_PROTOCOL_AF_INET6: if ((size_t) (end - buf) < sizeof(ngx_proxy_protocol_inet6_addrs_t)) { return NULL; } in6 = (ngx_proxy_protocol_inet6_addrs_t *) buf; src_sockaddr.sockaddr_in6.sin6_family = AF_INET6; src_sockaddr.sockaddr_in6.sin6_port = 0; memcpy(&src_sockaddr.sockaddr_in6.sin6_addr, in6->src_addr, 16); dst_sockaddr.sockaddr_in6.sin6_family = AF_INET6; dst_sockaddr.sockaddr_in6.sin6_port = 0; memcpy(&dst_sockaddr.sockaddr_in6.sin6_addr, in6->dst_addr, 16); pp->src_port = ngx_proxy_protocol_parse_uint16(in6->src_port); pp->dst_port = ngx_proxy_protocol_parse_uint16(in6->dst_port); socklen = sizeof(struct sockaddr_in6); buf += sizeof(ngx_proxy_protocol_inet6_addrs_t); break; #endif default: ngx_log_debug1(NGX_LOG_DEBUG_CORE, c->log, 0, "PROXY protocol v2 unsupported address family %ui", family); return end; } pp->src_addr.data = ngx_pnalloc(c->pool, NGX_SOCKADDR_STRLEN); if (pp->src_addr.data == NULL) { return NULL; } pp->src_addr.len = ngx_sock_ntop(&src_sockaddr.sockaddr, socklen, pp->src_addr.data, NGX_SOCKADDR_STRLEN, 0); pp->dst_addr.data = ngx_pnalloc(c->pool, NGX_SOCKADDR_STRLEN); if (pp->dst_addr.data == NULL) { return NULL; } pp->dst_addr.len = ngx_sock_ntop(&dst_sockaddr.sockaddr, socklen, pp->dst_addr.data, NGX_SOCKADDR_STRLEN, 0); ngx_log_debug4(NGX_LOG_DEBUG_CORE, c->log, 0, "PROXY protocol v2 src: %V %d, dst: %V %d", &pp->src_addr, pp->src_port, &pp->dst_addr, pp->dst_port); if (buf < end) { ngx_log_debug1(NGX_LOG_DEBUG_CORE, c->log, 0, "PROXY protocol v2 %z bytes of tlv ignored", end - buf); } c->proxy_protocol = pp; return end; }