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-rw-r--r--sqmail-4.3.07/src/tls_remote.c387
1 files changed, 0 insertions, 387 deletions
diff --git a/sqmail-4.3.07/src/tls_remote.c b/sqmail-4.3.07/src/tls_remote.c
deleted file mode 100644
index 1318b4e..0000000
--- a/sqmail-4.3.07/src/tls_remote.c
+++ /dev/null
@@ -1,387 +0,0 @@
-#include <unistd.h>
-#include "ucspissl.h"
-#include "fmt.h"
-#include "stralloc.h"
-#include "str.h"
-#include "byte.h"
-#include "case.h"
-#include "dns.h"
-#include "constmap.h"
-#include "tls_remote.h"
-#include "tls_errors.h"
-
-/** @file tls_remote.c -- TLS client functions
- @brief connection functions: tls_conn, tls_exit;
- verification functions: tls_certkey, tls_checkpeer, tls_fingerprint, tlsa_check;
- tls_destination, tls_domaincert
- dummy functions: tls_crlcheck
-
- tls_checkpeer: r = 0 -> ADH, r = 1 -> wildcard DN, r = 2 -> DN, r = 3 -> CA; r < 0 -> error
- tls_fingerprint: r = 0 -> failed, r = 1 -> ok; r < 0 -> error
- tlsa_check: r = 0 -> nothing, r = usage + 1, r < 0 -> error
-*/
-
-/* Caution: OpenSSL's X509_pubkey_digest() does not work as expected.
- I've included now: X509_pkey_digest() and X509_cert_digest() (as makro) */
-
-#define X509_cert_digest X509_digest
-
-int tls_certkey(SSL_CTX *ctx,const char *cert,const char *key,char *ppwd)
-{
- if (!cert) return 0;
-
- if (SSL_CTX_use_certificate_chain_file(ctx,cert) != 1)
- return -1;
-
- if (!key) key = cert;
-
- if (ppwd) SSL_CTX_set_default_passwd_cb_userdata(ctx,ppwd);
-
- if (SSL_CTX_use_PrivateKey_file(ctx,key,SSL_FILETYPE_PEM) != 1)
- return -2;
-
- if (SSL_CTX_check_private_key(ctx) != 1)
- return -3;
-
- return 0;
-}
-
-int tls_conn(SSL *ssl,int smtpfd)
-{
- SSL_set_options(ssl,SSL_OP_NO_SSLv2);
- SSL_set_options(ssl,SSL_OP_NO_SSLv3);
- return SSL_set_fd(ssl,smtpfd);
-}
-
-int tls_checkpeer(SSL *ssl,X509 *cert,const stralloc host,const int flag,const int verify)
-{
- STACK_OF(GENERAL_NAME) *extensions;
- const GENERAL_NAME *ext;
- char buf[SSL_NAME_LEN];
- char *dnsname = 0;
- int dname = 0;
- int num;
- int len;
- int fflag;
- int i;
- int rc = 0;
-
- fflag = flag;
- if (flag > 20) fflag = flag - 20;
- if (flag > 10) fflag = flag - 10;
-
- /* X.509 CA DN/SAN name validation against DNS */
-
- if (host.len && fflag > 4) {
- extensions = (GENERAL_NAME *)X509_get_ext_d2i(cert,NID_subject_alt_name,0,0);
- num = sk_GENERAL_NAME_num(extensions); /* num = 0, if no SAN extensions */
-
- for (i = 0; i < num; ++i) {
- ext = sk_GENERAL_NAME_value(extensions,i);
- if (ext->type == GEN_DNS) {
- #if (OPENSSL_VERSION_NUMBER < 0x10100000L) // 0xmnnffppsL
- if (ASN1_STRING_type(ext->d.ia5) != V_ASN1_IA5STRING) continue;
- dnsname = (char *)ASN1_STRING_data(ext->d.ia5);
- #else
- if (OBJ_sn2nid((const char*)ext->d.ia5) != V_ASN1_IA5STRING) continue;
- dnsname = (char *)ASN1_STRING_get0_data(ext->d.ia5);
- #endif
- len = ASN1_STRING_length(ext->d.ia5);
- dname = 1;
- }
- }
-
- if (!dname) {
- X509_NAME_get_text_by_NID(X509_get_subject_name(cert),NID_commonName,buf,sizeof(buf));
- buf[SSL_NAME_LEN - 1] = 0;
- dnsname = buf;
- len = SSL_NAME_LEN - 1;
- }
-
- switch (fflag) {
- case 5: if (dnsname[0] == '*' && dnsname[1] == '.')
- if (case_diffrs(dnsname + 1,host.s)) return -3;
- if (case_diffrs(dnsname,host.s)) return -3;
- rc = 3; break;
- case 6: if (case_diffs(dnsname,host.s)) return -3;
- rc = 2; break;
- }
- }
-
- /* X.509 CA Verification: root CA must be available */
-
- if (fflag > 3 && verify > -2) {
- if (SSL_get_verify_result(ssl) != X509_V_OK) return -2;
- else rc = 1;
- }
-
- return rc;
-}
-
-int tls_checkcrl(SSL *ssl) // not implemented yet
-{
-
- return 0;
-}
-
-int dig_ascii(char *digascii,const char *digest,const int len)
-{
- static const char hextab[] = "0123456789abcdef";
- int j;
-
- for (j = 0; j < len; j++) {
- digascii[2 * j] = hextab[(unsigned char)digest[j] >> 4];
- digascii[2 * j + 1] = hextab[(unsigned char)digest[j] & 0x0f];
- }
- digascii[2 * len] = '\0';
-
- return (2 * j); // 2*len
-}
-
-/* X509_pkey_digest() takes the same args as X509_digest();
- however returning the correct hash of pubkey in md.
- Subjects keys are restricted to 2048 byte in size.
- Return codes: 1: sucess, 0: failed. */
-
-int X509_pkey_digest(const X509 *cert,const EVP_MD *type,unsigned char *md,unsigned int *dlen)
-{
- unsigned int len = 0;
- unsigned int size = 2048;
- unsigned char *buf;
- unsigned char *buf2;
- unsigned char buffer[size]; // avoid malloc
-
-/* Following Viktor's suggestion */
-
- if (!X509_get0_pubkey_bitstr(cert)) return 0; // no Subject public key
-
- len = i2d_X509_PUBKEY(X509_get_X509_PUBKEY(cert),0);
- if (len > size) return 0;
- buf2 = buf = buffer;
- i2d_X509_PUBKEY(X509_get_X509_PUBKEY(cert),(unsigned char **)&buf2);
- if (buf2 - buf != len) return 0;
-
- if (!EVP_Digest(buf,len,md,dlen,type,0)) return 0; // OpenSSL voodoo
- return 1;
-}
-
-/* Return codes: -4: no X.509 cert (fatal), -3: matching error (deferred),
- -2: unsupported type, -1: weird TLSA record
- 0: No X.509 cert; seen: usage++; */
-
-int tlsa_check(const STACK_OF(X509) *certs,const stralloc host,const unsigned long p)
-{
- const EVP_MD *methodsha256 = EVP_sha256();
- const EVP_MD *methodsha512 = EVP_sha512();
- stralloc out = {0};
- stralloc sa = {0};
- stralloc cn = {0};
- unsigned char digest[EVP_MAX_MD_SIZE];
- unsigned int dlen = 0;
- unsigned int n = 0;
- int i = 0;
- int r;
- char port[FMT_ULONG];
- uint16 type;
- uint16 selector;
- uint16 usage;
-
-// construct TLSA FQDN -- simple procedure; returning Usage
-
- if (host.len < 2) return 0;
- if (!stralloc_copyb(&sa,"_",1)) temp_nomem();
- port[fmt_ulong(port,p)] = 0;
- if (!stralloc_cats(&sa,port)) temp_nomem();
- if (!stralloc_cats(&sa,"._tcp.")) temp_nomem();
- if (!stralloc_cats(&sa,host.s)) temp_nomem();
-
- if (dns_cname(&cn,&sa) > 0) // query name could be a cname
- { if (dns_tlsa(&out,&cn) <= 0) return 0; }
- else
- { if (dns_tlsa(&out,&sa) <= 0) return 0; }
- if (out.len < 5) return -1;
-
- /* https://www.openssl.org/docs/man3.0/man3/X509_digest.html (1.1.1):
- "The len parameter, if not NULL, points to a place where the digest size will be stored."
- [sigh]
- */
-
- do {
- usage = (unsigned char) out.s[i]; // Usage: PKIX-TA [0], PKIX-EE [1], DANE-TA [2], DANE-EE [3]
- selector = (unsigned char) out.s[i + 1]; // Selector: 0 = Cert, 1 = SPKI
- type = (unsigned char) out.s[i + 2]; // Type: 0/1/2 = [Cert|SPKI]/SHA256/SHA512
-
- unsigned len = sk_X509_num(certs);
- for (n = 0; n < len; n++) {
- X509 *cert = sk_X509_value(certs,n);
- if (type == 1) {
- if (selector == 0) r = X509_cert_digest(cert,methodsha256,digest,&dlen);
- if (selector == 1) r = X509_pkey_digest(cert,methodsha256,digest,&dlen);
- } else if (type == 2) {
- if (selector == 0) r = X509_cert_digest(cert,methodsha512,digest,&dlen);
- if (selector == 1) r = X509_pkey_digest(cert,methodsha512,digest,&dlen);
- } else
- return -2;
-
- if (!byte_diff(digest,dlen,out.s + i + 3)) return ++usage;
- }
-
- i += (dlen + 3);
- } while (i < out.len - 4);
-
- return -3;
-}
-
-int tls_fingerprint(X509 *cert,const char *fingerprint,int dlen)
-{
- const EVP_MD *methodsha1 = EVP_sha1();
- const EVP_MD *methodsha224 = EVP_sha224();
- const EVP_MD *methodsha256 = EVP_sha256();
- const EVP_MD *methodsha512 = EVP_sha512();
- unsigned char digest[EVP_MAX_MD_SIZE];
- unsigned char digascii[257];
- unsigned int len;
-
- switch (dlen) { /* fetch digest from cert; len = bitlength/8 */
- case 40: if (!X509_digest(cert,methodsha1,digest,&len)) return -2;
- case 56: if (!X509_digest(cert,methodsha224,digest,&len)) return -2;
- case 64: if (!X509_digest(cert,methodsha256,digest,&len)) return -2;
- case 128: if (!X509_digest(cert,methodsha512,digest,&len)) return -2;
- default: return -3;
- }
-
- len = dig_ascii(digascii,digest,len);
- if (!str_diffn(digascii,fingerprint,len)) return 1;
-
- return 0;
-}
-
-int tls_exit(SSL *ssl)
-{
- if (SSL_shutdown(ssl) == 0)
- SSL_shutdown(ssl);
-
- return 0;
-}
-
-/** @brief tls_destination
- @param stralloc hostname (maybe 0-terminated)
-
- Certificate Fallthru
-
- @return values: | ADH | Cert *DN FQDN Hash | noTLSA noTLS
- ----------+-----+--------------------+-------------
- optional TLS | 1 | 3 - - - | - 9
- mandatory TLS | 2 | 4 5 6 7 | 8
-
- no TLS -1
- */
-
-int tls_destination(const stralloc hostname)
-{
- int i;
- stralloc tlshost = {0};
- stralloc tlsdest = {0};
-
- if (!stralloc_copy(&tlshost,&hostname)) temp_nomem();
- if (!stralloc_0(&tlshost)) temp_nomem();
-
-// Host rules
-
- if (!stralloc_copys(&tlsdest,"!")) temp_nomem();
- if (!stralloc_cats(&tlsdest,tlshost.s)) temp_nomem();
- if ((tlsdestinfo = constmap(&maptlsdestinations,tlsdest.s,tlsdest.len))) return -1;
-
- if (!stralloc_copys(&tlsdest,"?")) temp_nomem();
- if (!stralloc_cats(&tlsdest,tlshost.s)) temp_nomem();
- if ((tlsdestinfo = constmap(&maptlsdestinations,tlsdest.s,tlsdest.len))) return 9;
-
- if (!stralloc_copys(&tlsdest,"/")) temp_nomem();
- if (!stralloc_cats(&tlsdest,tlshost.s)) temp_nomem();
- if ((tlsdestinfo = constmap(&maptlsdestinations,tlsdest.s,tlsdest.len))) return 8;
-
- if (!stralloc_copys(&tlsdest,"%")) temp_nomem(); // CERT + hash
- if (!stralloc_cats(&tlsdest,tlshost.s)) temp_nomem();
- if ((tlsdestinfo = constmap(&maptlsdestinations,tlsdest.s,tlsdest.len))) return 7;
-
- if (!stralloc_copys(&tlsdest,"=")) temp_nomem(); // CERT + FQDN
- if (!stralloc_cats(&tlsdest,tlshost.s)) temp_nomem();
- if ((tlsdestinfo = constmap(&maptlsdestinations,tlsdest.s,tlsdest.len))) return 6;
-
- if (!stralloc_copys(&tlsdest,"~")) temp_nomem(); // CERT + Wild
- if (!stralloc_cats(&tlsdest,tlshost.s)) temp_nomem();
- if ((tlsdestinfo = constmap(&maptlsdestinations,tlsdest.s,tlsdest.len))) return 5;
-
-// Domain rules
-
- for (i = 0; i < tlshost.len; ++i) // TLS fallthru
- if ((i == 0) || (tlshost.s[i] == '.')) {
- if (!stralloc_copys(&tlsdest,"?")) temp_nomem();
- if (!stralloc_cats(&tlsdest,tlshost.s + i)) temp_nomem();
- if ((tlsdestinfo = constmap(&maptlsdestinations,tlsdest.s,tlsdest.len))) return 9;
- }
-
- for (i = 0; i < tlshost.len; ++i) // no TLSA
- if ((i == 0) || (tlshost.s[i] == '.')) {
- if (!stralloc_copys(&tlsdest,"/")) temp_nomem();
- if (!stralloc_cats(&tlsdest,tlshost.s + i)) temp_nomem();
- if ((tlsdestinfo = constmap(&maptlsdestinations,tlsdest.s,tlsdest.len))) return 8;
- }
-
- for (i = 0; i < tlshost.len; ++i) // CERT + Wild
- if ((i == 0) || (tlshost.s[i] == '.')) {
- if (!stralloc_copys(&tlsdest,"~")) temp_nomem();
- if (!stralloc_cats(&tlsdest,tlshost.s + i)) temp_nomem();
- if ((tlsdestinfo = constmap(&maptlsdestinations,tlsdest.s,tlsdest.len))) return 5;
- }
-
- for (i = 0; i < tlshost.len; ++i) // CERT - generic
- if ((i == 0) || (tlshost.s[i] == '.')) {
- if (!stralloc_copys(&tlsdest,"")) temp_nomem();
- if (!stralloc_cats(&tlsdest,tlshost.s + i)) temp_nomem();
- if ((tlsdestinfo = constmap(&maptlsdestinations,tlsdest.s,tlsdest.len))) return 4;
- }
-
- for (i = 0; i < tlshost.len; ++i) // ADH per host/domain
- if ((i == 0) || (tlshost.s[i] == '.')) {
- if (!stralloc_copys(&tlsdest,"-")) temp_nomem();
- if (!stralloc_cats(&tlsdest,tlshost.s + i)) temp_nomem();
- if ((tlsdestinfo = constmap(&maptlsdestinations,tlsdest.s,tlsdest.len))) return 2;
- }
-
-// General rules (mandatory TLS)
-
- tlsdestinfo = 0;
- if (constmap(&maptlsdestinations,"/*",2)) return 8; // no TLSA
- if (constmap(&maptlsdestinations,"=*",2)) return 6; // CERT + FQDN
- if (constmap(&maptlsdestinations,"~*",2)) return 5; // CERT + Wild
- if (constmap(&maptlsdestinations,"+*",2)) return 4; // CERT
- if (constmap(&maptlsdestinations,"-*",2)) return 2; // ADH
-
-// Fall thru rules (optional TLS)
-
- if (constmap(&maptlsdestinations,"?",1)) return 9; // fallback to no TLS
- if (constmap(&maptlsdestinations,"*",1)) return 3; // CERT
- if (constmap(&maptlsdestinations,"-",1)) return 1; // ADH
-
- return 0;
-}
-
-int tls_domaincerts(const stralloc domainname)
-{
- int i;
- tlsdomaininfo = 0; // extern
-
-/* Our Certs - per domain */
-
- if (domainname.len)
- for (i = 0; i < domainname.len; ++i)
- if ((i == 0) || (domainname.s[i] == '.'))
- if ((tlsdomaininfo = constmap(&mapdomaincerts,domainname.s + i,domainname.len - i))) return 2;
-
-/* Standard Cert (if any) */
-
- if ((tlsdomaininfo = constmap(&mapdomaincerts,"*",1))) return 1;
-
- return 0;
-}
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