From 622ae4621ece72a9f64b5602c74d7aaf373c1631 Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Mon, 28 Dec 2020 17:44:17 -0500 Subject: [PATCH] Fix assorted issues in backend's GSSAPI encryption support. Unrecoverable errors detected by GSSAPI encryption can't just be reported with elog(ERROR) or elog(FATAL), because attempting to send the error report to the client is likely to lead to infinite recursion or loss of protocol sync. Instead make this code do what the SSL encryption code has long done, which is to just report any such failure to the server log (with elevel COMMERROR), then pretend we've lost the connection by returning errno = ECONNRESET. Along the way, fix confusion about whether message translation is done by pg_GSS_error() or its callers (the latter should do it), and make the backend version of that function work more like the frontend version. Avoid allocating the port->gss struct until it's needed; we surely don't need to allocate it in the postmaster. Improve logging of "connection authorized" messages with GSS enabled. (As part of this, I back-patched the code changes from dc11f31a1.) Make BackendStatusShmemSize() account for the GSS-related space that will be allocated by CreateSharedBackendStatus(). This omission could possibly cause out-of-shared-memory problems with very high max_connections settings. Remove arbitrary, pointless restriction that only GSS authentication can be used on a GSS-encrypted connection. Improve documentation; notably, document the fact that libpq now prefers GSS encryption over SSL encryption if both are possible. Per report from Mikael Gustavsson. Back-patch to v12 where this code was introduced. Discussion: https://postgr.es/m/e5b0b6ed05764324a2f3fe7acfc766d5@smhi.se --- doc/src/sgml/client-auth.sgml | 114 ++++++++++++++------------- doc/src/sgml/libpq.sgml | 19 +++++ doc/src/sgml/protocol.sgml | 54 ++++++++----- doc/src/sgml/runtime.sgml | 12 ++- src/backend/libpq/auth.c | 35 ++++---- src/backend/libpq/be-gssapi-common.c | 51 ++++++++---- src/backend/libpq/be-secure-gssapi.c | 98 +++++++++++++++++------ src/backend/libpq/be-secure.c | 4 +- src/backend/libpq/hba.c | 19 +---- src/backend/libpq/pqcomm.c | 27 +++---- src/backend/postmaster/pgstat.c | 12 ++- src/backend/postmaster/postmaster.c | 37 +-------- src/backend/utils/init/postinit.c | 21 +++-- src/include/libpq/be-gssapi-common.h | 2 +- src/include/libpq/libpq-be.h | 5 +- 15 files changed, 300 insertions(+), 210 deletions(-) diff --git a/doc/src/sgml/client-auth.sgml b/doc/src/sgml/client-auth.sgml index a0a9ac9eed..9a5c9318ce 100644 --- a/doc/src/sgml/client-auth.sgml +++ b/doc/src/sgml/client-auth.sgml @@ -198,14 +198,6 @@ hostnogssenc database userhostgssenc record is ignored except for logging a warning that it cannot match any connections. - - - Note that the only supported - authentication methods for use - with GSSAPI encryption - are gss, reject, - and trust. - @@ -1201,14 +1193,13 @@ omicron bryanh guest1 GSSAPI is an industry-standard protocol for secure authentication defined in RFC 2743. - PostgreSQL - supports GSSAPI for use as either an encrypted, - authenticated layer, or for authentication only. + supports GSSAPI for authentication, + communications encryption, or both. GSSAPI provides automatic authentication (single sign-on) for systems that support it. The authentication itself is secure. If GSSAPI encryption - (see hostgssenc) or SSL encryption are + or SSL encryption is used, the data sent along the database connection will be encrypted; otherwise, it will not. @@ -1220,37 +1211,46 @@ omicron bryanh guest1 When GSSAPI uses - Kerberos, it uses a standard principal - in the format + Kerberos, it uses a standard service + principal (authentication identity) name in the format servicename/hostname@realm. - The PostgreSQL server will accept any principal that is included in the keytab used by - the server, but care needs to be taken to specify the correct principal details when - making the connection from the client using the krbsrvname connection parameter. (See - also .) The installation default can be - changed from the default postgres at build time using - ./configure --with-krb-srvnam=whatever. - In most environments, - this parameter never needs to be changed. - Some Kerberos implementations might require a different service name, - such as Microsoft Active Directory which requires the service name - to be in upper case (POSTGRES). - - - hostname is the fully qualified host name of the - server machine. The service principal's realm is the preferred realm - of the server machine. + The principal name used by a particular installation is not encoded in + the PostgreSQL server in any way; rather it + is specified in the keytab file that the server + reads to determine its identity. If multiple principals are listed in + the keytab file, the server will accept any one of them. + The server's realm name is the preferred realm specified in the Kerberos + configuration file(s) accessible to the server. - Client principals can be mapped to different PostgreSQL - database user names with pg_ident.conf. For example, + When connecting, the client must know the principal name of the server + it intends to connect to. The servicename + part of the principal is ordinarily postgres, + but another value can be selected via libpq's + connection parameter. + The hostname part is the fully qualified + host name that libpq is told to connect to. + The realm name is the preferred realm specified in the Kerberos + configuration file(s) accessible to the client. + + + + The client will also have a principal name for its own identity + (and it must have a valid ticket for this principal). To + use GSSAPI for authentication, the client + principal must be associated with + a PostgreSQL database user name. + The pg_ident.conf configuration file can be used + to map principals to user names; for example, pgusername@realm could be mapped to just pgusername. Alternatively, you can use the full username@realm principal as the role name in PostgreSQL without any mapping. - PostgreSQL also supports a parameter to strip the realm from + PostgreSQL also supports mapping + client principals to user names by just stripping the realm from the principal. This method is supported for backwards compatibility and is strongly discouraged as it is then impossible to distinguish different users with the same user name but coming from different realms. To enable this, @@ -1264,39 +1264,34 @@ omicron bryanh guest1 - Make sure that your server keytab file is readable (and preferably - only readable, not writable) by the PostgreSQL - server account. (See also .) The location - of the key file is specified by the configuration parameter. The default is - /usr/local/pgsql/etc/krb5.keytab (or whatever - directory was specified as sysconfdir at build time). + FILE:/usr/local/pgsql/etc/krb5.keytab + (where the directory part is whatever was specified + as sysconfdir at build time). For security reasons, it is recommended to use a separate keytab just for the PostgreSQL server rather - than opening up permissions on the system keytab file. + than allowing the server to read the system keytab file. + Make sure that your server keytab file is readable (and preferably + only readable, not writable) by the PostgreSQL + server account. (See also .) + - The keytab file is generated by the Kerberos software; see the - Kerberos documentation for details. The following example is - for MIT-compatible Kerberos 5 implementations: + The keytab file is generated using the Kerberos software; see the + Kerberos documentation for details. The following example shows + doing this using the kadmin tool of + MIT-compatible Kerberos 5 implementations: -kadmin% ank -randkey postgres/server.my.domain.org +kadmin% addprinc -randkey postgres/server.my.domain.org kadmin% ktadd -k krb5.keytab postgres/server.my.domain.org - When connecting to the database make sure you have a ticket for a - principal matching the requested database user name. For example, for - database user name fred, principal - fred@EXAMPLE.COM would be able to connect. To also allow - principal fred/users.example.com@EXAMPLE.COM, use a user name - map, as described in . - - - - The following configuration options are supported for GSSAPI: + The following authentication options are supported for + the GSSAPI authentication method: include_realm @@ -1319,7 +1314,7 @@ omicron bryanh guest1 map - Allows for mapping between system and database user names. See + Allows mapping from client principals to database user names. See for details. For a GSSAPI/Kerberos principal, such as username@EXAMPLE.COM (or, less commonly, username/hostbased@EXAMPLE.COM), the @@ -1346,6 +1341,15 @@ omicron bryanh guest1 + + + In addition to these settings, which can be different for + different pg_hba.conf entries, there is the + server-wide configuration + parameter. If that is set to true, client principals are matched to + user map entries case-insensitively. krb_realm, if + set, is also matched case-insensitively. + diff --git a/doc/src/sgml/libpq.sgml b/doc/src/sgml/libpq.sgml index 67c5d4c36b..a5db58d468 100644 --- a/doc/src/sgml/libpq.sgml +++ b/doc/src/sgml/libpq.sgml @@ -1581,6 +1581,16 @@ postgresql://%2Fvar%2Flib%2Fpostgresql/dbname connection.SSLwith libpq + + + Note that if GSSAPI encryption is possible, + that will be used in preference to SSL + encryption, regardless of the value of sslmode. + To force use of SSL encryption in an + environment that has working GSSAPI + infrastructure (such as a Kerberos server), also + set gssencmode to disable. + @@ -1784,6 +1794,15 @@ postgresql://%2Fvar%2Flib%2Fpostgresql/dbname This must match the service name specified in the server configuration for Kerberos authentication to succeed. (See also .) + The default value is normally postgres, + but that can be changed when + building PostgreSQL via + the option + of configure. + In most environments, this parameter never needs to be changed. + Some Kerberos implementations might require a different service name, + such as Microsoft Active Directory which requires the service name + to be in upper case (POSTGRES). diff --git a/doc/src/sgml/protocol.sgml b/doc/src/sgml/protocol.sgml index 4899bacda7..98b42bb269 100644 --- a/doc/src/sgml/protocol.sgml +++ b/doc/src/sgml/protocol.sgml @@ -1454,6 +1454,10 @@ SELCT 1/0; SSL-encrypted. To continue after N, send the usual StartupMessage and proceed without encryption. + (Alternatively, it is permissible to issue a GSSENCRequest message + after an N response to try to + use GSSAPI encryption instead + of SSL.) @@ -1509,7 +1513,34 @@ SELCT 1/0; result from the server, until it returns no output. When sending the results of gss_init_sec_context() to the server, prepend the length of the message as a four byte integer in network byte - order. If this is successful, then use gss_wrap() to + order. + To continue after + N, send the usual StartupMessage and proceed without + encryption. + (Alternatively, it is permissible to issue an SSLRequest message + after an N response to try to + use SSL encryption instead + of GSSAPI.) + + + + The frontend should also be prepared to handle an ErrorMessage + response to GSSENCRequest from the server. This would only occur if + the server predates the addition of GSSAPI encryption + support to PostgreSQL. In this case the + connection must be closed, but the frontend might choose to open a fresh + connection and proceed without requesting GSSAPI + encryption. + + + + An initial GSSENCRequest can also be used in a connection that is being + opened to send a CancelRequest message. + + + + Once GSSAPI encryption has been successfully + established, use gss_wrap() to encrypt the usual StartupMessage and all subsequent data, prepending the length of the result from gss_wrap() as a four byte integer in network byte order to the actual encrypted payload. Note that @@ -1520,26 +1551,7 @@ SELCT 1/0; gss_wrap() calls. Typical segments are 8kB of unencrypted data, resulting in encrypted packets of slightly larger than 8kB but well within the 16kB maximum. The server can be expected to not send - encrypted packets of larger than 16kB to the client. To continue after - N, send the usual StartupMessage and proceed without - encryption. - - - - The frontend should also be prepared to handle an ErrorMessage - response to GSSENCRequest from the server. This would only occur if - the server predates the addition of GSSAPI encryption - support to PostgreSQL. In this case the - connection must be closed, but the frontend might choose to open a fresh - connection and proceed without requesting GSSAPI - encryption. Given the length limits specified above, the ErrorMessage can - not be confused with a proper response from the server with an appropriate - length. - - - - An initial GSSENCRequest can also be used in a connection that is being - opened to send a CancelRequest message. + encrypted packets of larger than 16kB to the client. diff --git a/doc/src/sgml/runtime.sgml b/doc/src/sgml/runtime.sgml index 17e938148c..283352d3a4 100644 --- a/doc/src/sgml/runtime.sgml +++ b/doc/src/sgml/runtime.sgml @@ -2563,7 +2563,7 @@ openssl x509 -req -in server.csr -text -days 365 \ PostgreSQL also has native support for using GSSAPI to encrypt client/server communications for increased security. Support requires that a GSSAPI - implementation (such as MIT krb5) is installed on both client and server + implementation (such as MIT Kerberos) is installed on both client and server systems, and that support in PostgreSQL is enabled at build time (see ). @@ -2582,6 +2582,16 @@ openssl x509 -req -in server.csr -text -days 365 \ some or all connections. + + When using GSSAPI for encryption, it is common to + use GSSAPI for authentication as well, since the + underlying mechanism will determine both client and server identities + (according to the GSSAPI implementation) in any + case. But this is not required; + another PostgreSQL authentication method + can be chosen to perform additional verification. + + Other than configuration of the negotiation behavior, GSSAPI encryption requires no setup beyond diff --git a/src/backend/libpq/auth.c b/src/backend/libpq/auth.c index 3d80930968..d4ec965934 100644 --- a/src/backend/libpq/auth.c +++ b/src/backend/libpq/auth.c @@ -382,17 +382,6 @@ ClientAuthentication(Port *port) errmsg("connection requires a valid client certificate"))); } -#ifdef ENABLE_GSS - if (port->gss->enc && port->hba->auth_method != uaReject && - port->hba->auth_method != uaImplicitReject && - port->hba->auth_method != uaTrust && - port->hba->auth_method != uaGSS) - { - ereport(FATAL, (errcode(ERRCODE_INVALID_AUTHORIZATION_SPECIFICATION), - errmsg("GSSAPI encryption can only be used with gss, trust, or reject authentication methods"))); - } -#endif - /* * Now proceed to do the actual authentication check */ @@ -533,7 +522,17 @@ ClientAuthentication(Port *port) case uaGSS: #ifdef ENABLE_GSS + /* We might or might not have the gss workspace already */ + if (port->gss == NULL) + port->gss = (pg_gssinfo *) + MemoryContextAllocZero(TopMemoryContext, + sizeof(pg_gssinfo)); port->gss->auth = true; + + /* + * If GSS state was set up while enabling encryption, we can just + * check the client's principal. Otherwise, ask for it. + */ if (port->gss->enc) status = pg_GSS_checkauth(port); else @@ -548,6 +547,10 @@ ClientAuthentication(Port *port) case uaSSPI: #ifdef ENABLE_SSPI + if (port->gss == NULL) + port->gss = (pg_gssinfo *) + MemoryContextAllocZero(TopMemoryContext, + sizeof(pg_gssinfo)); sendAuthRequest(port, AUTH_REQ_SSPI, NULL, 0); status = pg_SSPI_recvauth(port); #else @@ -1185,9 +1188,9 @@ pg_GSS_recvauth(Port *port) if (maj_stat != GSS_S_COMPLETE && maj_stat != GSS_S_CONTINUE_NEEDED) { gss_delete_sec_context(&lmin_s, &port->gss->ctx, GSS_C_NO_BUFFER); - pg_GSS_error(ERROR, - _("accepting GSS security context failed"), + pg_GSS_error(_("accepting GSS security context failed"), maj_stat, min_stat); + return STATUS_ERROR; } if (maj_stat == GSS_S_CONTINUE_NEEDED) @@ -1224,9 +1227,11 @@ pg_GSS_checkauth(Port *port) */ maj_stat = gss_display_name(&min_stat, port->gss->name, &gbuf, NULL); if (maj_stat != GSS_S_COMPLETE) - pg_GSS_error(ERROR, - _("retrieving GSS user name failed"), + { + pg_GSS_error(_("retrieving GSS user name failed"), maj_stat, min_stat); + return STATUS_ERROR; + } /* * Copy the original name of the authenticated principal into our backend diff --git a/src/backend/libpq/be-gssapi-common.c b/src/backend/libpq/be-gssapi-common.c index ef9b8ebd6d..be5d051c20 100644 --- a/src/backend/libpq/be-gssapi-common.c +++ b/src/backend/libpq/be-gssapi-common.c @@ -17,8 +17,9 @@ #include "libpq/be-gssapi-common.h" /* - * Helper function for getting all strings of a GSSAPI error (of specified - * stat). Call once for GSS_CODE and once for MECH_CODE. + * Fetch all errors of a specific type and append to "s" (buffer of size len). + * If we obtain more than one string, separate them with spaces. + * Call once for GSS_CODE and once for MECH_CODE. */ static void pg_GSS_error_int(char *s, size_t len, OM_uint32 stat, int type) @@ -28,31 +29,49 @@ pg_GSS_error_int(char *s, size_t len, OM_uint32 stat, int type) OM_uint32 lmin_s, msg_ctx = 0; - gmsg.value = NULL; - gmsg.length = 0; + s[0] = '\0'; /* just in case gss_display_status fails */ do { - gss_display_status(&lmin_s, stat, type, - GSS_C_NO_OID, &msg_ctx, &gmsg); - strlcpy(s + i, gmsg.value, len - i); + if (gss_display_status(&lmin_s, stat, type, GSS_C_NO_OID, + &msg_ctx, &gmsg) != GSS_S_COMPLETE) + break; + if (i > 0) + { + if (i < len) + s[i] = ' '; + i++; + } + if (i < len) + strlcpy(s + i, gmsg.value, len - i); i += gmsg.length; gss_release_buffer(&lmin_s, &gmsg); } - while (msg_ctx && i < len); + while (msg_ctx); - if (msg_ctx || i == len) - ereport(WARNING, - (errmsg_internal("incomplete GSS error report"))); + if (i >= len) + { + elog(COMMERROR, "incomplete GSS error report"); + s[len - 1] = '\0'; /* ensure string is nul-terminated */ + } } /* - * Fetch and report all error messages from GSSAPI. To avoid allocation, - * total error size is capped (at 128 bytes for each of major and minor). No - * known mechanisms will produce error messages beyond this cap. + * Report the GSSAPI error described by maj_stat/min_stat. + * + * errmsg should be an already-translated primary error message. + * The GSSAPI info is appended as errdetail. + * + * The error is always reported with elevel COMMERROR; we daren't try to + * send it to the client, as that'd likely lead to infinite recursion + * when elog.c tries to write to the client. + * + * To avoid memory allocation, total error size is capped (at 128 bytes for + * each of major and minor). No known mechanisms will produce error messages + * beyond this cap. */ void -pg_GSS_error(int severity, const char *errmsg, +pg_GSS_error(const char *errmsg, OM_uint32 maj_stat, OM_uint32 min_stat) { char msg_major[128], @@ -68,7 +87,7 @@ pg_GSS_error(int severity, const char *errmsg, * errmsg_internal, since translation of the first part must be done * before calling this function anyway. */ - ereport(severity, + ereport(COMMERROR, (errmsg_internal("%s", errmsg), errdetail_internal("%s: %s", msg_major, msg_minor))); } diff --git a/src/backend/libpq/be-secure-gssapi.c b/src/backend/libpq/be-secure-gssapi.c index 5a73302b7b..1747fccb14 100644 --- a/src/backend/libpq/be-secure-gssapi.c +++ b/src/backend/libpq/be-secure-gssapi.c @@ -21,6 +21,7 @@ #include "libpq/pqformat.h" #include "miscadmin.h" #include "pgstat.h" +#include "utils/memutils.h" /* @@ -81,10 +82,14 @@ static uint32 PqGSSMaxPktSize; /* Maximum size we can encrypt and fit the * transport negotiation is complete). * * On success, returns the number of data bytes consumed (possibly less than - * len). On failure, returns -1 with errno set appropriately. (For fatal - * errors, we may just elog and exit, if errno wouldn't be sufficient to - * describe the error.) For retryable errors, caller should call again - * (passing the same data) once the socket is ready. + * len). On failure, returns -1 with errno set appropriately. For retryable + * errors, caller should call again (passing the same data) once the socket + * is ready. + * + * Dealing with fatal errors here is a bit tricky: we can't invoke elog(FATAL) + * since it would try to write to the client, probably resulting in infinite + * recursion. Instead, use elog(COMMERROR) to log extra info about the + * failure if necessary, and then return an errno indicating connection loss. */ ssize_t be_gssapi_write(Port *port, void *ptr, size_t len) @@ -108,8 +113,11 @@ be_gssapi_write(Port *port, void *ptr, size_t len) * again, so if it offers a len less than that, something is wrong. */ if (len < PqGSSSendConsumed) - elog(FATAL, "GSSAPI caller failed to retransmit all data needing to be retried"); - + { + elog(COMMERROR, "GSSAPI caller failed to retransmit all data needing to be retried"); + errno = ECONNRESET; + return -1; + } /* Discount whatever source data we already encrypted. */ bytes_to_encrypt = len - PqGSSSendConsumed; bytes_encrypted = PqGSSSendConsumed; @@ -192,17 +200,27 @@ be_gssapi_write(Port *port, void *ptr, size_t len) major = gss_wrap(&minor, gctx, 1, GSS_C_QOP_DEFAULT, &input, &conf_state, &output); if (major != GSS_S_COMPLETE) - pg_GSS_error(FATAL, gettext_noop("GSSAPI wrap error"), major, minor); - + { + pg_GSS_error(_("GSSAPI wrap error"), major, minor); + errno = ECONNRESET; + return -1; + } if (conf_state == 0) - ereport(FATAL, + { + ereport(COMMERROR, (errmsg("outgoing GSSAPI message would not use confidentiality"))); - + errno = ECONNRESET; + return -1; + } if (output.length > PQ_GSS_SEND_BUFFER_SIZE - sizeof(uint32)) - ereport(FATAL, + { + ereport(COMMERROR, (errmsg("server tried to send oversize GSSAPI packet (%zu > %zu)", (size_t) output.length, PQ_GSS_SEND_BUFFER_SIZE - sizeof(uint32)))); + errno = ECONNRESET; + return -1; + } bytes_encrypted += input.length; bytes_to_encrypt -= input.length; @@ -234,9 +252,11 @@ be_gssapi_write(Port *port, void *ptr, size_t len) * transport negotiation is complete). * * Returns the number of data bytes read, or on failure, returns -1 - * with errno set appropriately. (For fatal errors, we may just elog and - * exit, if errno wouldn't be sufficient to describe the error.) For - * retryable errors, caller should call again once the socket is ready. + * with errno set appropriately. For retryable errors, caller should call + * again once the socket is ready. + * + * We treat fatal errors the same as in be_gssapi_write(), even though the + * argument about infinite recursion doesn't apply here. */ ssize_t be_gssapi_read(Port *port, void *ptr, size_t len) @@ -326,10 +346,14 @@ be_gssapi_read(Port *port, void *ptr, size_t len) input.length = pg_ntoh32(*(uint32 *) PqGSSRecvBuffer); if (input.length > PQ_GSS_RECV_BUFFER_SIZE - sizeof(uint32)) - ereport(FATAL, + { + ereport(COMMERROR, (errmsg("oversize GSSAPI packet sent by the client (%zu > %zu)", (size_t) input.length, PQ_GSS_RECV_BUFFER_SIZE - sizeof(uint32)))); + errno = ECONNRESET; + return -1; + } /* * Read as much of the packet as we are able to on this call into @@ -361,12 +385,18 @@ be_gssapi_read(Port *port, void *ptr, size_t len) major = gss_unwrap(&minor, gctx, &input, &output, &conf_state, NULL); if (major != GSS_S_COMPLETE) - pg_GSS_error(FATAL, gettext_noop("GSSAPI unwrap error"), - major, minor); - + { + pg_GSS_error(_("GSSAPI unwrap error"), major, minor); + errno = ECONNRESET; + return -1; + } if (conf_state == 0) - ereport(FATAL, + { + ereport(COMMERROR, (errmsg("incoming GSSAPI message did not use confidentiality"))); + errno = ECONNRESET; + return -1; + } memcpy(PqGSSResultBuffer, output.value, output.length); PqGSSResultLength = output.length; @@ -468,6 +498,12 @@ secure_open_gssapi(Port *port) OM_uint32 major, minor; + /* + * Allocate subsidiary Port data for GSSAPI operations. + */ + port->gss = (pg_gssinfo *) + MemoryContextAllocZero(TopMemoryContext, sizeof(pg_gssinfo)); + /* * Allocate buffers and initialize state variables. By malloc'ing the * buffers at this point, we avoid wasting static data space in processes @@ -521,10 +557,13 @@ secure_open_gssapi(Port *port) * Verify on our side that the client doesn't do something funny. */ if (input.length > PQ_GSS_RECV_BUFFER_SIZE) - ereport(FATAL, + { + ereport(COMMERROR, (errmsg("oversize GSSAPI packet sent by the client (%zu > %d)", (size_t) input.length, PQ_GSS_RECV_BUFFER_SIZE))); + return -1; + } /* * Get the rest of the packet so we can pass it to GSSAPI to accept @@ -544,7 +583,7 @@ secure_open_gssapi(Port *port) NULL, NULL); if (GSS_ERROR(major)) { - pg_GSS_error(ERROR, gettext_noop("could not accept GSSAPI security context"), + pg_GSS_error(_("could not accept GSSAPI security context"), major, minor); gss_release_buffer(&minor, &output); return -1; @@ -570,10 +609,14 @@ secure_open_gssapi(Port *port) uint32 netlen = pg_hton32(output.length); if (output.length > PQ_GSS_SEND_BUFFER_SIZE - sizeof(uint32)) - ereport(FATAL, + { + ereport(COMMERROR, (errmsg("server tried to send oversize GSSAPI packet (%zu > %zu)", (size_t) output.length, PQ_GSS_SEND_BUFFER_SIZE - sizeof(uint32)))); + gss_release_buffer(&minor, &output); + return -1; + } memcpy(PqGSSSendBuffer, (char *) &netlen, sizeof(uint32)); PqGSSSendLength += sizeof(uint32); @@ -634,8 +677,10 @@ secure_open_gssapi(Port *port) &PqGSSMaxPktSize); if (GSS_ERROR(major)) - pg_GSS_error(FATAL, gettext_noop("GSSAPI size check error"), - major, minor); + { + pg_GSS_error(_("GSSAPI size check error"), major, minor); + return -1; + } port->gss->enc = true; @@ -667,12 +712,13 @@ be_gssapi_get_enc(Port *port) } /* - * Return the GSSAPI principal used for authentication on this connection. + * Return the GSSAPI principal used for authentication on this connection + * (NULL if we did not perform GSSAPI authentication). */ const char * be_gssapi_get_princ(Port *port) { - if (!port || !port->gss->auth) + if (!port || !port->gss) return NULL; return port->gss->princ; diff --git a/src/backend/libpq/be-secure.c b/src/backend/libpq/be-secure.c index 2ae507a902..59bc02e79c 100644 --- a/src/backend/libpq/be-secure.c +++ b/src/backend/libpq/be-secure.c @@ -160,7 +160,7 @@ retry: else #endif #ifdef ENABLE_GSS - if (port->gss->enc) + if (port->gss && port->gss->enc) { n = be_gssapi_read(port, ptr, len); waitfor = WL_SOCKET_READABLE; @@ -273,7 +273,7 @@ retry: else #endif #ifdef ENABLE_GSS - if (port->gss->enc) + if (port->gss && port->gss->enc) { n = be_gssapi_write(port, ptr, len); waitfor = WL_SOCKET_WRITEABLE; diff --git a/src/backend/libpq/hba.c b/src/backend/libpq/hba.c index 0cc4397769..99319b273a 100644 --- a/src/backend/libpq/hba.c +++ b/src/backend/libpq/hba.c @@ -1447,19 +1447,6 @@ parse_hba_line(TokenizedLine *tok_line, int elevel) *err_msg = "gssapi authentication is not supported on local sockets"; return NULL; } - if (parsedline->conntype == ctHostGSS && - parsedline->auth_method != uaGSS && - parsedline->auth_method != uaReject && - parsedline->auth_method != uaTrust) - { - ereport(elevel, - (errcode(ERRCODE_CONFIG_FILE_ERROR), - errmsg("GSSAPI encryption only supports gss, trust, or reject authentication"), - errcontext("line %d of configuration file \"%s\"", - line_num, HbaFileName))); - *err_msg = "GSSAPI encryption only supports gss, trust, or reject authentication"; - return NULL; - } if (parsedline->conntype != ctLocal && parsedline->auth_method == uaPeer) @@ -2134,9 +2121,11 @@ check_hba(hbaPort *port) /* Check GSSAPI state */ #ifdef ENABLE_GSS - if (port->gss->enc && hba->conntype == ctHostNoGSS) + if (port->gss && port->gss->enc && + hba->conntype == ctHostNoGSS) continue; - else if (!port->gss->enc && hba->conntype == ctHostGSS) + else if (!(port->gss && port->gss->enc) && + hba->conntype == ctHostGSS) continue; #else if (hba->conntype == ctHostGSS) diff --git a/src/backend/libpq/pqcomm.c b/src/backend/libpq/pqcomm.c index 0b511008fc..3ea7c6167e 100644 --- a/src/backend/libpq/pqcomm.c +++ b/src/backend/libpq/pqcomm.c @@ -256,30 +256,27 @@ socket_close(int code, Datum arg) /* Nothing to do in a standalone backend, where MyProcPort is NULL. */ if (MyProcPort != NULL) { -#if defined(ENABLE_GSS) || defined(ENABLE_SSPI) #ifdef ENABLE_GSS - OM_uint32 min_s; - /* * Shutdown GSSAPI layer. This section does nothing when interrupting * BackendInitialize(), because pg_GSS_recvauth() makes first use of * "ctx" and "cred". + * + * Note that we don't bother to free MyProcPort->gss, since we're + * about to exit anyway. */ - if (MyProcPort->gss->ctx != GSS_C_NO_CONTEXT) - gss_delete_sec_context(&min_s, &MyProcPort->gss->ctx, NULL); + if (MyProcPort->gss) + { + OM_uint32 min_s; - if (MyProcPort->gss->cred != GSS_C_NO_CREDENTIAL) - gss_release_cred(&min_s, &MyProcPort->gss->cred); + if (MyProcPort->gss->ctx != GSS_C_NO_CONTEXT) + gss_delete_sec_context(&min_s, &MyProcPort->gss->ctx, NULL); + + if (MyProcPort->gss->cred != GSS_C_NO_CREDENTIAL) + gss_release_cred(&min_s, &MyProcPort->gss->cred); + } #endif /* ENABLE_GSS */ - /* - * GSS and SSPI share the port->gss struct. Since nowhere else does a - * postmaster child free this, doing so is safe when interrupting - * BackendInitialize(). - */ - free(MyProcPort->gss); -#endif /* ENABLE_GSS || ENABLE_SSPI */ - /* * Cleanly shut down SSL layer. Nowhere else does a postmaster child * call this, so this is safe when interrupting BackendInitialize(). diff --git a/src/backend/postmaster/pgstat.c b/src/backend/postmaster/pgstat.c index d87d9d06ee..123369f4fa 100644 --- a/src/backend/postmaster/pgstat.c +++ b/src/backend/postmaster/pgstat.c @@ -2888,6 +2888,11 @@ BackendStatusShmemSize(void) /* BackendSslStatusBuffer: */ size = add_size(size, mul_size(sizeof(PgBackendSSLStatus), NumBackendStatSlots)); +#endif +#ifdef ENABLE_GSS + /* BackendGssStatusBuffer: */ + size = add_size(size, + mul_size(sizeof(PgBackendGSSStatus), NumBackendStatSlots)); #endif return size; } @@ -3172,12 +3177,13 @@ pgstat_bestart(void) #ifdef ENABLE_GSS if (MyProcPort && MyProcPort->gss != NULL) { + const char *princ = be_gssapi_get_princ(MyProcPort); + lbeentry.st_gss = true; lgssstatus.gss_auth = be_gssapi_get_auth(MyProcPort); lgssstatus.gss_enc = be_gssapi_get_enc(MyProcPort); - - if (lgssstatus.gss_auth) - strlcpy(lgssstatus.gss_princ, be_gssapi_get_princ(MyProcPort), NAMEDATALEN); + if (princ) + strlcpy(lgssstatus.gss_princ, princ, NAMEDATALEN); } else { diff --git a/src/backend/postmaster/postmaster.c b/src/backend/postmaster/postmaster.c index fff4227e0b..b3ccd18cda 100644 --- a/src/backend/postmaster/postmaster.c +++ b/src/backend/postmaster/postmaster.c @@ -2052,6 +2052,7 @@ retry1: else if (proto == NEGOTIATE_GSS_CODE && !gss_done) { char GSSok = 'N'; + #ifdef ENABLE_GSS /* No GSSAPI encryption when on Unix socket */ if (!IS_AF_UNIX(port->laddr.addr.ss_family)) @@ -2520,37 +2521,19 @@ ConnCreate(int serverFd) return NULL; } - /* - * Allocate GSSAPI specific state struct - */ -#ifndef EXEC_BACKEND -#if defined(ENABLE_GSS) || defined(ENABLE_SSPI) - port->gss = (pg_gssinfo *) calloc(1, sizeof(pg_gssinfo)); - if (!port->gss) - { - ereport(LOG, - (errcode(ERRCODE_OUT_OF_MEMORY), - errmsg("out of memory"))); - ExitPostmaster(1); - } -#endif -#endif - return port; } /* * ConnFree -- free a local connection data structure + * + * Caller has already closed the socket if any, so there's not much + * to do here. */ static void ConnFree(Port *conn) { -#ifdef USE_SSL - secure_close(conn); -#endif - if (conn->gss) - free(conn->gss); free(conn); } @@ -4906,18 +4889,6 @@ SubPostmasterMain(int argc, char *argv[]) /* Setup as postmaster child */ InitPostmasterChild(); - /* - * Set up memory area for GSS information. Mirrors the code in ConnCreate - * for the non-exec case. - */ -#if defined(ENABLE_GSS) || defined(ENABLE_SSPI) - port.gss = (pg_gssinfo *) calloc(1, sizeof(pg_gssinfo)); - if (!port.gss) - ereport(FATAL, - (errcode(ERRCODE_OUT_OF_MEMORY), - errmsg("out of memory"))); -#endif - /* * If appropriate, physically re-attach to shared memory segment. We want * to do this before going any further to ensure that we can attach at the diff --git a/src/backend/utils/init/postinit.c b/src/backend/utils/init/postinit.c index 82d451569d..9723e457ce 100644 --- a/src/backend/utils/init/postinit.c +++ b/src/backend/utils/init/postinit.c @@ -270,11 +270,22 @@ PerformAuthentication(Port *port) be_tls_get_compression(port) ? _("on") : _("off")); #endif #ifdef ENABLE_GSS - if (be_gssapi_get_princ(port)) - appendStringInfo(&logmsg, _(" GSS (authenticated=%s, encrypted=%s, principal=%s)"), - be_gssapi_get_auth(port) ? _("yes") : _("no"), - be_gssapi_get_enc(port) ? _("yes") : _("no"), - be_gssapi_get_princ(port)); + if (port->gss) + { + const char *princ = be_gssapi_get_princ(port); + + if (princ) + appendStringInfo(&logmsg, + _(" GSS (authenticated=%s, encrypted=%s, principal=%s)"), + be_gssapi_get_auth(port) ? _("yes") : _("no"), + be_gssapi_get_enc(port) ? _("yes") : _("no"), + princ); + else + appendStringInfo(&logmsg, + _(" GSS (authenticated=%s, encrypted=%s)"), + be_gssapi_get_auth(port) ? _("yes") : _("no"), + be_gssapi_get_enc(port) ? _("yes") : _("no")); + } #endif ereport(LOG, errmsg_internal("%s", logmsg.data)); diff --git a/src/include/libpq/be-gssapi-common.h b/src/include/libpq/be-gssapi-common.h index edf89675cf..e1c23ac545 100644 --- a/src/include/libpq/be-gssapi-common.h +++ b/src/include/libpq/be-gssapi-common.h @@ -20,7 +20,7 @@ #include #endif -void pg_GSS_error(int severity, const char *errmsg, +extern void pg_GSS_error(const char *errmsg, OM_uint32 maj_stat, OM_uint32 min_stat); #endif /* BE_GSSAPI_COMMON_H */ diff --git a/src/include/libpq/libpq-be.h b/src/include/libpq/libpq-be.h index 0a23281ad5..fa778e1192 100644 --- a/src/include/libpq/libpq-be.h +++ b/src/include/libpq/libpq-be.h @@ -176,8 +176,9 @@ typedef struct Port #if defined(ENABLE_GSS) || defined(ENABLE_SSPI) /* - * If GSSAPI is supported, store GSSAPI information. Otherwise, store a - * NULL pointer to make sure offsets in the struct remain the same. + * If GSSAPI is supported and used on this connection, store GSSAPI + * information. Even when GSSAPI is not compiled in, store a NULL pointer + * to keep struct offsets the same (for extension ABI compatibility). */ pg_gssinfo *gss; #else