this change moves stack of compression methods, now global variable

in libssl into crypto context. This change is rquired by atexit PR.

build.info

@@ -47,7 +47,8 @@ DEPEND[]=include/openssl/asn1.h \
          include/openssl/x509_acert.h \
          include/openssl/x509_vfy.h \
          include/crypto/bn_conf.h include/crypto/dso_conf.h \
-         include/internal/param_names.h crypto/params_idx.c
+         include/internal/param_names.h \
+         include/internal/stack_of_comp_methods.h crypto/params_idx.c
 
 GENERATE[include/openssl/asn1.h]=include/openssl/asn1.h.in
 GENERATE[include/openssl/asn1t.h]=include/openssl/asn1t.h.in
@@ -83,9 +84,11 @@ GENERATE[include/crypto/dso_conf.h]=include/crypto/dso_conf.h.in
 
 DEPEND[crypto/params_idx.c \
        include/internal/param_names.h \
+       include/internal/stack_of_comp_methods.h \
        include/openssl/core_names.h]=util/perl|OpenSSL/paramnames.pm
 GENERATE[crypto/params_idx.c]=crypto/params_idx.c.in
 GENERATE[include/internal/param_names.h]=include/internal/param_names.h.in
+GENERATE[include/internal/stack_of_comp_methods.h]=include/internal/stack_of_comp_methods.h.in
 GENERATE[include/openssl/core_names.h]=include/openssl/core_names.h.in
 
 IF[{- defined $target{shared_defflag} -}]

crypto/build.info

@@ -104,10 +104,10 @@ $UTIL_COMMON=\
 
 SOURCE[../libcrypto]=$UTIL_COMMON \
         mem.c mem_sec.c \
-        cversion.c info.c cpt_err.c ebcdic.c uid.c o_time.c o_dir.c \
-        o_fopen.c getenv.c o_init.c init.c trace.c provider.c provider_child.c \
-        punycode.c passphrase.c sleep.c deterministic_nonce.c quic_vlint.c \
-        time.c
+        comp_methods.c cversion.c info.c cpt_err.c ebcdic.c uid.c o_time.c \
+        o_dir.c o_fopen.c getenv.c o_init.c init.c trace.c provider.c \
+        provider_child.c punycode.c passphrase.c sleep.c deterministic_nonce.c \
+        quic_vlint.c time.c
 SOURCE[../providers/libfips.a]=$UTIL_COMMON
 
 SOURCE[../libcrypto]=$UPLINKSRC

crypto/comp_methods.c

@@ -0,0 +1,62 @@
+/*
+ * Copyright 2025 The OpenSSL Project Authors. All Rights Reserved.
+ *
+ * Licensed under the Apache License 2.0 (the "License").  You may not use
+ * this file except in compliance with the License.  You can obtain a copy
+ * in the file LICENSE in the source distribution or at
+ * https://www.openssl.org/source/license.html
+ */
+
+#include <openssl/crypto.h>
+#include <openssl/comp.h>
+#include <openssl/obj_mac.h>
+
+#include "internal/cryptlib.h"
+
+#define OSSL_COMP_NULL_IDX       0
+#define OSSL_COMP_ZLIB_IDX       1
+#define OSSL_COMP_NUM_IDX        2
+
+static int sk_comp_cmp(const OSSL_COMP *const *a, const OSSL_COMP *const *b)
+{
+    return ((*a)->id - (*b)->id);
+}
+
+STACK_OF(OSSL_COMP) *ossl_load_builtin_compressions(void)
+{
+    STACK_OF(OSSL_COMP) *comp_methods = NULL;
+#ifndef OPENSSL_NO_COMP
+    OSSL_COMP *comp = NULL;
+    COMP_METHOD *method = COMP_zlib();
+
+    comp_methods = sk_OSSL_COMP_new(sk_comp_cmp);
+
+    if (COMP_get_type(method) != NID_undef && comp_methods != NULL) {
+        comp = OPENSSL_malloc(sizeof(*comp));
+        if (comp != NULL) {
+            comp->method = method;
+            comp->id = OSSL_COMP_ZLIB_IDX;
+            comp->name = COMP_get_name(method);
+            if (!sk_OSSL_COMP_push(comp_methods, comp))
+                OPENSSL_free(comp);
+            sk_OSSL_COMP_sort(comp_methods);
+        }
+    }
+#endif
+    return comp_methods;
+}
+
+STACK_OF(OSSL_COMP) *ossl_comp_get_compression_methods(OSSL_LIB_CTX *ctx)
+{
+    return ossl_lib_ctx_get_data(ctx, OSSL_LIB_CTX_COMP_METHODS);
+}
+
+static void cmeth_free(OSSL_COMP *cm)
+{
+    OPENSSL_free(cm);
+}
+
+void ossl_free_compression_methods_int(STACK_OF(OSSL_COMP) *methods)
+{
+    sk_OSSL_COMP_pop_free(methods, cmeth_free);
+}

crypto/context.c

@@ -11,12 +11,15 @@
 #include <openssl/conf.h>
 #include "internal/thread_once.h"
 #include "internal/property.h"
+#include "internal/cryptlib.h"
 #include "internal/core.h"
 #include "internal/bio.h"
 #include "internal/provider.h"
 #include "crypto/decoder.h"
 #include "crypto/context.h"
 
+#include "internal/cryptlib.h"
+
 struct ossl_lib_ctx_st {
     CRYPTO_RWLOCK *lock, *rand_crngt_lock;
     OSSL_EX_DATA_GLOBAL global;
@@ -48,6 +51,7 @@ struct ossl_lib_ctx_st {
     void *thread_event_handler;
     void *fips_prov;
 #endif
+    void *comp_methods;
 
     int ischild;
     int conf_diagnostics;
@@ -204,6 +208,10 @@ static int context_init(OSSL_LIB_CTX *ctx)
     if (!ossl_property_parse_init(ctx))
         goto err;
 
+#ifndef FIPS_MODULE
+    ctx->comp_methods = ossl_load_builtin_compressions();
+#endif
+
     return 1;
 
  err:
@@ -344,6 +352,14 @@ static void context_deinit_objs(OSSL_LIB_CTX *ctx)
         ctx->child_provider = NULL;
     }
 #endif
+
+#ifndef FIPS_MODULE
+    if (ctx->comp_methods != NULL) {
+        ossl_free_compression_methods_int(ctx->comp_methods);
+        ctx->comp_methods = NULL;
+    }
+#endif
+
 }
 
 static int context_deinit(OSSL_LIB_CTX *ctx)
@@ -634,11 +650,19 @@ void *ossl_lib_ctx_get_data(OSSL_LIB_CTX *ctx, int index)
         return ctx->fips_prov;
 #endif
 
+    case OSSL_LIB_CTX_COMP_METHODS:
+        return ctx->comp_methods;
+
     default:
         return NULL;
     }
 }
 
+void *OSSL_LIB_CTX_get_data(OSSL_LIB_CTX *ctx, int index)
+{
+    return ossl_lib_ctx_get_data(ctx, index);
+}
+
 OSSL_EX_DATA_GLOBAL *ossl_lib_ctx_get_ex_data_global(OSSL_LIB_CTX *ctx)
 {
     ctx = ossl_lib_ctx_get_concrete(ctx);
@@ -683,3 +707,18 @@ void OSSL_LIB_CTX_set_conf_diagnostics(OSSL_LIB_CTX *libctx, int value)
         return;
     libctx->conf_diagnostics = value;
 }
+
+void *OSSL_LIB_CTX_set0_compression_methods(OSSL_LIB_CTX *ctx, void *meths)
+{
+    STACK_OF(OSSL_COMP) *comp_methods;
+
+    ctx = ossl_lib_ctx_get_concrete(ctx);
+    if (ctx != NULL) {
+        comp_methods = ctx->comp_methods;
+        ctx->comp_methods = meths;
+    } else {
+        comp_methods = NULL;
+    }
+
+    return comp_methods;
+}

doc/man3/OSSL_LIB_CTX.pod

@@ -4,7 +4,9 @@
 
 OSSL_LIB_CTX, OSSL_LIB_CTX_new, OSSL_LIB_CTX_new_from_dispatch,
 OSSL_LIB_CTX_new_child, OSSL_LIB_CTX_free, OSSL_LIB_CTX_load_config,
-OSSL_LIB_CTX_get0_global_default, OSSL_LIB_CTX_set0_default
+OSSL_LIB_CTX_get0_global_default, OSSL_LIB_CTX_set0_default,
+OSSL_LIB_CTX_get_data, OSSL_LIB_CTX_set0_compression_methods
+
 - OpenSSL library context
 
 =head1 SYNOPSIS
@@ -22,6 +24,8 @@ OSSL_LIB_CTX_get0_global_default, OSSL_LIB_CTX_set0_default
  void OSSL_LIB_CTX_free(OSSL_LIB_CTX *ctx);
  OSSL_LIB_CTX *OSSL_LIB_CTX_get0_global_default(void);
  OSSL_LIB_CTX *OSSL_LIB_CTX_set0_default(OSSL_LIB_CTX *ctx);
+ void *OSSL_LIB_CTX_get_data(OSSL_LIB_CTX *ctx, int index);
+ void *OSSL_LIB_CTX_set0_compression_methods(OSSL_LIB_CTX *ctx, void *methods);
 
 =head1 DESCRIPTION
 
@@ -111,6 +115,15 @@ in the mean time.  This means that the calling thread must not free the
 library context that was the default at the start of the async job before
 that job has finished.
 
+OSSL_LIB_CTX_get_data() returns pointer to data/object member bound to context
+instance (ctx). The index argument refers to context member which is to
+be retrieved. The values for index are private to OpenSSL currently.
+If ctx is NULL then function operates on default crypto library context.
+
+OSSL_LIB_CTX_set0_compression_methods() function swaps compression methods
+member in library context with new methods. Function returns original
+methods to caller.
+
 =head1 RETURN VALUES
 
 OSSL_LIB_CTX_new(), OSSL_LIB_CTX_get0_global_default() and
@@ -121,10 +134,19 @@ OSSL_LIB_CTX_free() doesn't return any value.
 
 OSSL_LIB_CTX_load_config() returns 1 on success, 0 on error.
 
+OSSL_LIB_CTX_get_data() returns pointer to desired object associated with
+library context instance.
+
+OSSL_LIB_CTX_set0_compression_methods() returns pointer to compression
+methods which got replaced.
+
 =head1 HISTORY
 
 All of the functions described on this page were added in OpenSSL 3.0.
 
+OSSL_LIB_CTX_get_data() and OSSL_LIB_CTX_set0_compression_methods()
+were introduced in OpenSSL 3.4.
+
 =head1 COPYRIGHT
 
 Copyright 2019-2021 The OpenSSL Project Authors. All Rights Reserved.

include/internal/cryptlib.h

@@ -86,6 +86,15 @@ typedef struct ossl_ex_data_global_st {
     EX_CALLBACKS ex_data[CRYPTO_EX_INDEX__COUNT];
 } OSSL_EX_DATA_GLOBAL;
 
+typedef struct ossl_comp_st {
+    int id;
+    const char *name;
+    COMP_METHOD *method;
+} OSSL_COMP;
+
+STACK_OF(OSSL_COMP);
+
+# include "internal/stack_of_comp_methods.h"
 
 /* OSSL_LIB_CTX */
 
@@ -117,7 +126,8 @@ typedef struct ossl_ex_data_global_st {
 # define OSSL_LIB_CTX_CHILD_PROVIDER_INDEX          18
 # define OSSL_LIB_CTX_THREAD_INDEX                  19
 # define OSSL_LIB_CTX_DECODER_CACHE_INDEX           20
-# define OSSL_LIB_CTX_MAX_INDEXES                   20
+# define OSSL_LIB_CTX_COMP_METHODS                  21
+# define OSSL_LIB_CTX_MAX_INDEXES                   21
 
 OSSL_LIB_CTX *ossl_lib_ctx_get_concrete(OSSL_LIB_CTX *ctx);
 int ossl_lib_ctx_is_default(OSSL_LIB_CTX *ctx);
@@ -161,4 +171,8 @@ char *ossl_buf2hexstr_sep(const unsigned char *buf, long buflen, char sep);
 unsigned char *ossl_hexstr2buf_sep(const char *str, long *buflen,
                                    const char sep);
 
+STACK_OF(OSSL_COMP) *ossl_load_builtin_compressions(void);
+STACK_OF(OSSL_COMP) *ossl_comp_get_compression_methods(OSSL_LIB_CTX *ctx);
+void ossl_free_compression_methods_int(STACK_OF(OSSL_COMP) *methods);
+
 #endif

include/internal/stack_of_comp_methods.h.in

@@ -0,0 +1,21 @@
+/*
+ * Copyright 2024 The OpenSSL Project Authors. All Rights Reserved.
+ *
+ * Licensed under the Apache License 2.0 (the "License").  You may not use
+ * this file except in compliance with the License.  You can obtain a copy
+ * in the file LICENSE in the source distribution or at
+ * https://www.openssl.org/source/license.html
+ */
+
+{-
+use OpenSSL::stackhash qw(generate_stack_macros generate_const_stack_macros);
+-}
+
+#ifndef OPENSSL_STACK_OF_COMP_METHODS_H
+
+{-
+    generate_stack_macros("OSSL_COMP");
+-}
+
+#endif
+

include/openssl/crypto.h.in

@@ -541,6 +541,10 @@ void OSSL_LIB_CTX_set_conf_diagnostics(OSSL_LIB_CTX *ctx, int value);
 
 void OSSL_sleep(uint64_t millis);
 
+
+void *OSSL_LIB_CTX_set0_compression_methods(OSSL_LIB_CTX *ctx, void *meths);
+void *OSSL_LIB_CTX_get_data(OSSL_LIB_CTX *ctx, int index);
+
 # ifdef  __cplusplus
 }
 # endif

include/openssl/ssl.h.in

@@ -236,7 +236,7 @@ typedef struct ssl_cipher_st SSL_CIPHER;
 typedef struct ssl_session_st SSL_SESSION;
 typedef struct tls_sigalgs_st TLS_SIGALGS;
 typedef struct ssl_conf_ctx_st SSL_CONF_CTX;
-typedef struct ssl_comp_st SSL_COMP;
+typedef struct ossl_comp_st SSL_COMP;
 
 STACK_OF(SSL_CIPHER);
 STACK_OF(SSL_COMP);