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-rw-r--r--scan_certificate.c393
1 files changed, 0 insertions, 393 deletions
diff --git a/scan_certificate.c b/scan_certificate.c
deleted file mode 100644
index 4cffcf7..0000000
--- a/scan_certificate.c
+++ /dev/null
@@ -1,393 +0,0 @@
-#include <stdlib.h>
-#include <stdio.h>
-#include "asn1.h"
-#include <str.h>
-#include "textcode.h"
-#include "fmt.h"
-#include "byte.h"
-
-struct x509signature {
- struct string oid; /* you are not expected to actually decode this */
- size_t oididx; /* if this is (size_t)-1, then the parser did not know the OID.
- Otherwise it's the index into oid2string. oid2string[oididx].id
- should be something like X509_ALG_SHA1RSA (see asn1.h) */
- struct string bitstring; /* In this string, the length is in bits, not bytes! */
- /* If the length is not a multiple of 8, then the unused bits are missing in the last byte.
- * The parser already validated that the last byte is padded with 0 bits */
-};
-
-struct x509cert {
- enum { v1=0, v1988=0, v2=1, v3=2, v1996=2 } version;
- size_t serial;
- struct x509signature algid;
- struct string issuer; /* this is the raw asn.1 structure, a SET of "[{op}]" in scan_asn1generic terms */
- time_t notbefore, notafter;
- struct string subject; /* this is the raw asn.1 structure, a SET of "[{op}]" in scan_asn1generic terms */
- struct x509signature sig;
-};
-
-struct rsaprivatekey {
- size_t* modulus,* publicExponent,* privateExponent,* prime1,* prime2,* exponent1,* exponent2,* coefficient;
- struct string otherPrimeInfos;
- size_t* freewhendone;
-};
-
-struct dsaprivatekey {
-};
-
-void printasn1(const char* buf,const char* max);
-
-static int findindn(struct string* dn,enum x509_oid id,struct string* dest) {
- size_t i;
- const char* c=dn->s;
- const char* max=dn->s+dn->l;
- for (;;) {
- struct string oid;
- size_t l=scan_asn1generic(c,max,"[{op}]",&oid,dest);
- if (l) {
- i=lookupoid(oid.s,oid.l);
- if (i!=(size_t)-1) { // recognized the oid!
- if (oid2string[i].id==id)
- return 1;
- }
- c+=l;
- } else break;
- }
- return 0;
-}
-
-static size_t base64_decode(const char* cert, size_t l, const char* name, char** dest) {
- /* cert should be something like "-----BEGIN CERTIFICATE-----\n[base64 gunk]\n-----END CERTIFICATE-----\n"
- * l should be strlen(cert), but cert does not need to be 0-terminated
- * name should be something like "CERTIFICATE" or "RSA PRIVATE KEY", what you are trying to decode
- * dest will end up pointing to the decoded data.
- * return value can be 0 if we can't decode the data and it does not
- * look like it's a binary certificate. Or it can be some length
- * value, in which case dest points to a malloced area of that length
- * with the decoded data in it. */
- size_t taglen=strlen(name)+sizeof("-----BEGIN -----")-1;
- char tag[taglen+1];
- char* c=0,* x;
- tag[fmt_strm(tag,"-----BEGIN ",name,"-----")]=0;
- if (l > 2*taglen && byte_equal(cert,taglen,tag))
-certfound:
- {
- size_t cur,used;
- /* "-----BEGIN CERTIFICATE-----", "-----END CERTIFICATE-----" and newlines */
- c=malloc((l-2*taglen)/4*3);
- if (!c) return 0;
- x=c;
- for (cur=taglen; cur+taglen-1<l;) {
- size_t next;
- if (cert[cur]=='\r') ++cur; /* skip line ending */
- if (cert[cur]=='\n') ++cur;
- next=scan_base64(cert+cur,x,&used);
- if (next==0) break;
- cur+=next;
- x+=used;
- }
- if (!str_start(cert+cur,"-----END ") ||
- byte_diff(cert+cur+sizeof("-----END"),taglen-sizeof("----BEGIN")-1,tag+sizeof("-----BEGIN"))) {
- free(c);
- return 0;
- }
- cert=c;
- l=x-c;
- } else {
- /* Maybe it has text in front of the BEGIN CERTIFICATE line */
- size_t i,a=1;
- for (i=0; i+27+25+2<l; ++i) {
- if (cert[i]!='\n' && cert[i]!='\r' && (cert[i]<' ' || cert[i]>'~')) {
- a=0;
- break;
- }
- if (byte_equal(cert+i,taglen,tag)) {
- cert+=i;
- l-=i;
- goto certfound;
- }
- }
- if (a) /* if we end up here, it was ascii but did not contain a certificate. fail. */
- return 0;
- }
- /* if we end up here, we decoded some base64 data or we found some
- * binary data. See if it looks like x.509 at all. If it does, it
- * starts with a SEQUENCE_OF, which encodes as '0'. */
- if (*cert!='0') {
-parseerror:
- free(c);
- return 0;
- }
- *dest=c;
- return l;
-}
-
-size_t scan_rsaprivatekey(const char* cert, size_t l, struct rsaprivatekey* C, char** freewhendone) {
- char* c;
- size_t maxdigits,ret;
- unsigned long version;
- *freewhendone=NULL;
- l=base64_decode(cert,l,"RSA PRIVATE KEY",&c);
- if (!l) return 0;
- if (c!=cert) *freewhendone=c;
- maxdigits=l/sizeof(size_t)+2;
- C->freewhendone=malloc(maxdigits*sizeof(size_t)*8);
- if (!C->freewhendone) {
-fail:
- free(*freewhendone);
- freewhendone=NULL;
- return 0;
- }
- C->modulus=C->freewhendone;
- C->publicExponent=C->modulus+maxdigits;
- C->privateExponent=C->publicExponent+maxdigits;
- C->prime1=C->privateExponent+maxdigits;
- C->prime2=C->prime1+maxdigits;
- C->exponent1=C->prime2+maxdigits;
- C->exponent2=C->exponent1+maxdigits;
- C->coefficient=C->exponent2+maxdigits;
- C->otherPrimeInfos.l=0;
- C->otherPrimeInfos.s=NULL;
- if ((ret=scan_asn1generic(c,c+l,"{iIIIIIIII!}",&version,
- C->modulus,C->publicExponent,C->privateExponent,
- C->prime1,C->prime2,C->exponent1,C->exponent2,
- C->coefficient,&C->otherPrimeInfos))) {
- if (version!=0 && version!=1) goto fail;
- if (version==0 && C->otherPrimeInfos.l) goto fail;
- if (version==1 && !C->otherPrimeInfos.l) goto fail;
- if (version==0) C->otherPrimeInfos.s=NULL;
- return ret;
- } else
- goto fail;
-}
-
-size_t scan_certificate(const char* cert, size_t l, struct x509cert* C, char** freewhendone) {
- char* c=0,* x;
- *freewhendone=NULL;
- l=base64_decode(cert,l,"CERTIFICATE",&c);
- if (!l) return 0;
- if (c!=cert) *freewhendone=c;
- cert=c;
-
- /* now for the heavy lifting */
- {
- unsigned long tagforversion; // must be 0
- unsigned long version;
- struct string oidalg,algparams,pubkeyalg,extensions,oidsig,sigrest,sigdata;
- size_t n,i;
- if ((n=scan_asn1generic(cert,cert+l,"{{ci]i{o!}{!}{uu}{!}{!}!}{o!}b}",
- &tagforversion,
- &version,
- &C->serial,
- &oidalg, &algparams,
- &C->issuer,
- &C->notbefore, &C->notafter,
- &C->subject,
- &pubkeyalg,
- &extensions,
- &oidsig, &sigrest, &sigdata))) {
-
- if (version==0)
- printf("X.509 certificate\n");
- else if (version==1)
- printf("X.509v2 certificate\n");
- else if (version==2)
- printf("X.509v3 certificate\n");
- else
- printf("unsupported version %ld (must be 0, 1 or 2)\n",version);
-
- printf("serial number %lu\n",C->serial);
-
- printf("issuer: ");
- {
- struct string s;
- if (findindn(&C->issuer,X509_ATTR_COUNTRY,&s))
- printf("C=%.*s ",(int)s.l,s.s);
- if (findindn(&C->issuer,X509_ATTR_ORG,&s))
- printf("O=%.*s ",(int)s.l,s.s);
- if (findindn(&C->issuer,X509_ATTR_COMMONNAME,&s))
- printf("CN=%.*s ",(int)s.l,s.s);
- }
- printf("\n");
-
- {
- char a[100],b[100];
- a[fmt_httpdate(a,C->notbefore)]=0;
- b[fmt_httpdate(b,C->notafter)]=0;
- printf("valid not before %s and not after %s\n",a,b);
- }
-
- printf("subject: ");
- {
- struct string s;
- if (findindn(&C->issuer,X509_ATTR_COUNTRY,&s))
- printf("C=%.*s ",(int)s.l,s.s);
- if (findindn(&C->issuer,X509_ATTR_ORG,&s))
- printf("O=%.*s ",(int)s.l,s.s);
- if (findindn(&C->issuer,X509_ATTR_COMMONNAME,&s))
- printf("CN=%.*s ",(int)s.l,s.s);
- }
- printf("\n");
-
- i=lookupoid(oidalg.s,oidalg.l);
- if (i!=(size_t)-1)
- printf("signature algorithm %s\n",oid2string[i].name);
- else {
- unsigned long temp[100];
- size_t len=100;
- if (scan_asn1rawoid(oidalg.s,oidalg.s+oidalg.l,temp,&len)) {
- printf("Unknown signature algorithm (oid ");
- for (i=0; i<len; ++i)
- printf("%lu%s",temp[i],i+1<len?".":")\n");
- } else
- printf("I don't know the algorithm and I can't parse/print the OID\n");
- }
-
- /* pubkeyalg is a SubjectPublicKeyInfo:
- SubjectPublicKeyInfo ::= SEQUENCE{
- algorithm AlgorithmIdentifier,
- subjectPublicKey BIT STRING}
-
- AlgorithmIdentifier ::= SEQUENCE{
- algorithm OBJECT IDENTIFIER,
- parameters ANY DEFINED BY algorithm OPTIONAL}
- */
-
- {
- struct string pubkeyoid, pubkeyparams, bits;
- if (scan_asn1generic(pubkeyalg.s,pubkeyalg.s+pubkeyalg.l,"{o!}b",&pubkeyoid,&pubkeyparams,&bits)) {
-
- i=lookupoid(pubkeyoid.s,pubkeyoid.l);
- if (i!=(size_t)-1) {
- printf("public key algorithm %s\n",oid2string[i].name);
- if (oid2string[i].id==X509_ALG_RSA) {
- size_t* modulus,* publicExponent;
- size_t allocsize=bits.l/8+2*sizeof(modulus[0]);
- modulus=malloc(allocsize);
- publicExponent=malloc(allocsize);
- if (!modulus || !publicExponent)
- printf("malloc for RSA bignums failed!\n");
- else {
- if (scan_asn1generic(bits.s,bits.s+bits.l/8,"{II}",modulus,publicExponent)) {
- if (publicExponent[0]==1)
- printf("public exponent %lu\n",publicExponent[1]);
- else
- printf("public exponent is larger than a word?!\n");
- printf("modulus:\n ");
- for (i=1; i<=modulus[0]; ++i) {
- size_t j,k;
- for (j=0, k=modulus[i]; j<sizeof(modulus[0]); ++j) {
- printf("%02lx%s",(k>>((sizeof(modulus[0])*8)-(j+1)*8))&0xff,i==modulus[0] && j==sizeof(modulus[0])-1?"":":");
- }
- if ((i-1)%4==3)
- if (i==modulus[0])
- printf("\n");
- else
- printf("\n ");
- }
- } else
- printf("bignum scanning failed!\n");
- }
- free(modulus); free(publicExponent);
- }
- } else {
- unsigned long temp[100];
- size_t len=100;
- if (scan_asn1rawoid(pubkeyoid.s,pubkeyoid.s+pubkeyoid.l,temp,&len)) {
- printf("Unknown public key algorithm (oid ");
- for (i=0; i<len; ++i)
- printf("%lu%s",temp[i],i+1<len?".":")\n");
- } else
- printf("I don't know the public key algorithm and I can't parse/print the OID\n");
- }
-
- } else
- printf("could not parse public key part!\n");
-
- // parse x.509v3 extensions
- if (version!=2 && extensions.l) {
- printf("Not X.509v3 but extensions present!?\n");
- } else if (extensions.l) {
- const char* c=extensions.s;
- const char* max=extensions.s+extensions.l;
- struct string extoid,extval;
- unsigned long noextensions;
- if (c!=max) {
- size_t n=scan_asn1generic(c,max,"c{!}}!",&noextensions,&extensions,&extval);
- if (n==0 || extval.l>0) {
- printf("failed to parse X.509v3 extensions!\n");
- c=max;
- } else {
- c=extensions.s;
- max=extensions.s+extensions.l;
- }
- }
- while (c<max) {
- size_t n=scan_asn1generic(c,max,"{os}",&extoid,&extval);
- if (n) {
- size_t i=lookupoid(extoid.s,extoid.l);
- if (i!=(size_t)-1) {
- printf("X.509 extension %s\n",oid2string[i].name);
- } else {
- unsigned long temp[100];
- size_t len=100;
- if (scan_asn1rawoid(extoid.s,extoid.s+extoid.l,temp,&len)) {
- printf("Unknown X.509v3 extension (oid ");
- for (i=0; i<len; ++i)
- printf("%lu%s",temp[i],i+1<len?".":")\n");
- } else
- printf("Failed to parse X.509v3 extension OID\n");
- }
- c+=n;
- } else {
- printf("X.509v3 extension parse error!\n");
- printasn1(c,max);
- break;
- }
- }
- }
- /*
- &extensions,
- &oidsig, &sigrest, &sigdata))) {
- */
- }
-
- return n;
-
- } else {
- printasn1(cert,cert+l);
- return 0;
- }
- }
-
-}
-
-#include "mmap.h"
-#include <stdio.h>
-
-#include "printasn1.c"
-
-int main(int argc,char* argv[]) {
- char* freewhendone;
- const char* buf;
- size_t l,n;
- struct x509cert c;
- struct rsaprivatekey k;
-
- buf=mmap_read(argc>1?argv[1]:"test.pem",&l);
- if (!buf) { puts("test.pem not found"); return 1; }
-
- n=scan_certificate(buf,l,&c,&freewhendone);
- if (!n)
- printf("failed to parse certificate\n");
- free(freewhendone);
-
- buf=mmap_read(argc>2?argv[2]:"privatekey.pem",&l);
- if (!buf) { puts("privatekey.pem not found"); return 1; }
-
- n=scan_rsaprivatekey(buf,l,&k,&freewhendone);
- if (!n)
- printf("failed to parse rsa private key\n");
- free(freewhendone);
- free(k.freewhendone);
-}
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