diff options
| -rw-r--r-- | lib/x509asn1.c | 249 |
1 files changed, 132 insertions, 117 deletions
diff --git a/lib/x509asn1.c b/lib/x509asn1.c index 5410e0575..25231921c 100644 --- a/lib/x509asn1.c +++ b/lib/x509asn1.c @@ -120,7 +120,7 @@ static const char *getASN1Element(curl_asn1Element *elem, if an error occurs. */ if(!beg || !end || beg >= end || !*beg || (size_t)(end - beg) > CURL_ASN1_MAX) - return (const char *) NULL; + return NULL; /* Process header byte. */ elem->header = beg; @@ -129,12 +129,12 @@ static const char *getASN1Element(curl_asn1Element *elem, elem->class = (b >> 6) & 3; b &= 0x1F; if(b == 0x1F) - return (const char *) NULL; /* Long tag values not supported here. */ + return NULL; /* Long tag values not supported here. */ elem->tag = b; /* Process length. */ if(beg >= end) - return (const char *) NULL; + return NULL; b = (unsigned char) *beg++; if(!(b & 0x80)) len = b; @@ -142,69 +142,72 @@ static const char *getASN1Element(curl_asn1Element *elem, /* Unspecified length. Since we have all the data, we can determine the effective length by skipping element until an end element is found. */ if(!elem->constructed) - return (const char *) NULL; + return NULL; elem->beg = beg; while(beg < end && *beg) { beg = getASN1Element(&lelem, beg, end); if(!beg) - return (const char *) NULL; + return NULL; } if(beg >= end) - return (const char *) NULL; + return NULL; elem->end = beg; return beg + 1; } else if((unsigned)b > (size_t)(end - beg)) - return (const char *) NULL; /* Does not fit in source. */ + return NULL; /* Does not fit in source. */ else { /* Get long length. */ len = 0; do { if(len & 0xFF000000L) - return (const char *) NULL; /* Lengths > 32 bits are not supported. */ + return NULL; /* Lengths > 32 bits are not supported. */ len = (len << 8) | (unsigned char) *beg++; } while(--b); } if(len > (size_t)(end - beg)) - return (const char *) NULL; /* Element data does not fit in source. */ + return NULL; /* Element data does not fit in source. */ elem->beg = beg; elem->end = beg + len; return elem->end; } +/* + * Search the null terminated OID or OID identifier in local table. + * Return the table entry pointer or NULL if not found. + */ static const curl_OID * searchOID(const char *oid) { const curl_OID *op; - - /* Search the null terminated OID or OID identifier in local table. - Return the table entry pointer or NULL if not found. */ - for(op = OIDtable; op->numoid; op++) if(!strcmp(op->numoid, oid) || strcasecompare(op->textoid, oid)) return op; - return (const curl_OID *) NULL; + return NULL; } +/* + * Convert an ASN.1 Boolean value into its string representation. Return the + * dynamically allocated string, or NULL if source is not an ASN.1 Boolean + * value. + */ + static const char *bool2str(const char *beg, const char *end) { - /* Convert an ASN.1 Boolean value into its string representation. - Return the dynamically allocated string, or NULL if source is not an - ASN.1 Boolean value. */ - if(end - beg != 1) - return (const char *) NULL; + return NULL; return strdup(*beg? "TRUE": "FALSE"); } +/* + * Convert an ASN.1 octet string to a printable string. + * Return the dynamically allocated string, or NULL if an error occurs. + */ static const char *octet2str(const char *beg, const char *end) { size_t n = end - beg; char *buf = NULL; - /* Convert an ASN.1 octet string to a printable string. - Return the dynamically allocated string, or NULL if an error occurs. */ - if(n <= (SIZE_T_MAX - 1) / 3) { buf = malloc(3 * n + 1); if(buf) @@ -220,21 +223,22 @@ static const char *bit2str(const char *beg, const char *end) Return the dynamically allocated string, or NULL if an error occurs. */ if(++beg > end) - return (const char *) NULL; + return NULL; return octet2str(beg, end); } +/* + * Convert an ASN.1 integer value into its string representation. + * Return the dynamically allocated string, or NULL if source is not an + * ASN.1 integer value. + */ static const char *int2str(const char *beg, const char *end) { unsigned long val = 0; size_t n = end - beg; - /* Convert an ASN.1 integer value into its string representation. - Return the dynamically allocated string, or NULL if source is not an - ASN.1 integer value. */ - if(!n) - return (const char *) NULL; + return NULL; if(n > 4) return octet2str(beg, end); @@ -249,6 +253,13 @@ static const char *int2str(const char *beg, const char *end) return curl_maprintf("%s%lx", val >= 10? "0x": "", val); } +/* + * Perform a lazy conversion from an ASN.1 typed string to UTF8. Allocate the + * destination buffer dynamically. The allocation size will normally be too + * large: this is to avoid buffer overflows. + * Terminate the string with a nul byte and return the converted + * string length. + */ static ssize_t utf8asn1str(char **to, int type, const char *from, const char *end) { @@ -259,13 +270,7 @@ utf8asn1str(char **to, int type, const char *from, const char *end) unsigned int wc; char *buf; - /* Perform a lazy conversion from an ASN.1 typed string to UTF8. Allocate the - destination buffer dynamically. The allocation size will normally be too - large: this is to avoid buffer overflows. - Terminate the string with a nul byte and return the converted - string length. */ - - *to = (char *) NULL; + *to = NULL; switch(type) { case CURL_ASN1_BMP_STRING: size = 2; @@ -341,97 +346,105 @@ utf8asn1str(char **to, int type, const char *from, const char *end) return outlength; } +/* + * Convert an ASN.1 String into its UTF-8 string representation. + * Return the dynamically allocated string, or NULL if an error occurs. + */ static const char *string2str(int type, const char *beg, const char *end) { char *buf; - - /* Convert an ASN.1 String into its UTF-8 string representation. - Return the dynamically allocated string, or NULL if an error occurs. */ - if(utf8asn1str(&buf, type, beg, end) < 0) - return (const char *) NULL; + return NULL; return buf; } -static int encodeUint(char *buf, int n, unsigned int x) +/* + * Decimal ASCII encode unsigned integer `x' into the buflen sized buffer at + * buf. Return the total number of encoded digits, even if larger than + * `buflen'. + */ +static size_t encodeUint(char *buf, size_t buflen, unsigned int x) { - int i = 0; + size_t i = 0; unsigned int y = x / 10; - /* Decimal ASCII encode unsigned integer `x' in the `n'-byte buffer at `buf'. - Return the total number of encoded digits, even if larger than `n'. */ - if(y) { - i = encodeUint(buf, n, y); + i = encodeUint(buf, buflen, y); x -= y * 10; } - if(i < n) + if(i < buflen) buf[i] = (char) ('0' + x); i++; - if(i < n) + if(i < buflen) buf[i] = '\0'; /* Store a terminator if possible. */ return i; } -static int encodeOID(char *buf, int n, const char *beg, const char *end) +/* + * Convert an ASN.1 OID into its dotted string representation. + * Store the result in th `n'-byte buffer at `buf'. + * Return the converted string length, or 0 on errors. + */ +static size_t encodeOID(char *buf, size_t buflen, + const char *beg, const char *end) { - int i; + size_t i; unsigned int x; unsigned int y; - /* Convert an ASN.1 OID into its dotted string representation. - Store the result in th `n'-byte buffer at `buf'. - Return the converted string length, or -1 if an error occurs. */ - /* Process the first two numbers. */ y = *(const unsigned char *) beg++; x = y / 40; y -= x * 40; - i = encodeUint(buf, n, x); - if(i < n) + i = encodeUint(buf, buflen, x); + if(i < buflen) buf[i] = '.'; i++; - i += encodeUint(buf + i, n - i, y); + if(i >= buflen) + i += encodeUint(NULL, 0, y); + else + i += encodeUint(buf + i, buflen - i, y); /* Process the trailing numbers. */ while(beg < end) { - if(i < n) + if(i < buflen) buf[i] = '.'; i++; x = 0; do { if(x & 0xFF000000) - return -1; + return 0; y = *(const unsigned char *) beg++; x = (x << 7) | (y & 0x7F); } while(y & 0x80); - i += encodeUint(buf + i, n - i, x); + if(i >= buflen) + i += encodeUint(NULL, 0, x); + else + i += encodeUint(buf + i, buflen - i, x); } - if(i < n) + if(i < buflen) buf[i] = '\0'; return i; } +/* + * Convert an ASN.1 OID into its dotted or symbolic string representation. + * Return the dynamically allocated string, or NULL if an error occurs. + */ + static const char *OID2str(const char *beg, const char *end, bool symbolic) { - char *buf = (char *) NULL; - const curl_OID * op; - int n; - char dummy[1]; - - /* Convert an ASN.1 OID into its dotted or symbolic string representation. - Return the dynamically allocated string, or NULL if an error occurs. */ - + char *buf = NULL; if(beg < end) { - n = encodeOID(dummy, 0, beg, end); - if(n >= 0) { - buf = malloc(n + 1); + size_t buflen = encodeOID(NULL, 0, beg, end); + if(buflen) { + buf = malloc(buflen + 1); /* one extra for the zero byte */ if(buf) { - encodeOID(buf, n, beg, end); - buf[n] = '\0'; + encodeOID(buf, buflen, beg, end); + buf[buflen] = '\0'; if(symbolic) { - op = searchOID(buf); + const curl_OID *op = searchOID(buf); if(op) { free(buf); buf = strdup(op->textoid); @@ -471,7 +484,7 @@ static const char *GTime2str(const char *beg, const char *end) sec2 = fracp[-1]; break; default: - return (const char *) NULL; + return NULL; } /* Scan for timezone, measure fractional seconds. */ @@ -507,15 +520,16 @@ static const char *GTime2str(const char *beg, const char *end) sep, tzl, tzp); } +/* + * Convert an ASN.1 UTC time to a printable string. + * Return the dynamically allocated string, or NULL if an error occurs. + */ static const char *UTime2str(const char *beg, const char *end) { const char *tzp; size_t tzl; const char *sec; - /* Convert an ASN.1 UTC time to a printable string. - Return the dynamically allocated string, or NULL if an error occurs. */ - for(tzp = beg; tzp < end && *tzp >= '0' && *tzp <= '9'; tzp++) ; /* Get the seconds. */ @@ -526,12 +540,12 @@ static const char *UTime2str(const char *beg, const char *end) case 2: break; default: - return (const char *) NULL; + return NULL; } /* Process timezone. */ if(tzp >= end) - return (const char *) NULL; + return NULL; if(*tzp == 'Z') { tzp = "GMT"; end = tzp + 3; @@ -546,13 +560,14 @@ static const char *UTime2str(const char *beg, const char *end) tzl, tzp); } +/* + * Convert an ASN.1 element to a printable string. + * Return the dynamically allocated string, or NULL if an error occurs. + */ static const char *ASN1tostr(curl_asn1Element *elem, int type) { - /* Convert an ASN.1 element to a printable string. - Return the dynamically allocated string, or NULL if an error occurs. */ - if(elem->constructed) - return (const char *) NULL; /* No conversion of structured elements. */ + return NULL; /* No conversion of structured elements. */ if(!type) type = elem->tag; /* Type not forced: use element tag as type. */ @@ -586,10 +601,14 @@ static const char *ASN1tostr(curl_asn1Element *elem, int type) return string2str(type, elem->beg, elem->end); } - return (const char *) NULL; /* Unsupported. */ + return NULL; /* Unsupported. */ } -static ssize_t encodeDN(char *buf, size_t n, curl_asn1Element *dn) +/* + * ASCII encode distinguished name at `dn' into the `buflen'-sized buffer at + * `buf'. Return the total string length, even if larger than `buflen'. + */ +static ssize_t encodeDN(char *buf, size_t buflen, curl_asn1Element *dn) { curl_asn1Element rdn; curl_asn1Element atv; @@ -601,9 +620,6 @@ static ssize_t encodeDN(char *buf, size_t n, curl_asn1Element *dn) const char *p3; const char *str; - /* ASCII encode distinguished name at `dn' into the `n'-byte buffer at `buf'. - Return the total string length, even if larger than `n'. */ - for(p1 = dn->beg; p1 < dn->end;) { p1 = getASN1Element(&rdn, p1, dn->end); if(!p1) @@ -627,7 +643,7 @@ static ssize_t encodeDN(char *buf, size_t n, curl_asn1Element *dn) for(p3 = str; isupper(*p3); p3++) ; for(p3 = (*p3 || p3 - str > 2)? "/": ", "; *p3; p3++) { - if(l < n) + if(l < buflen) buf[l] = *p3; l++; } @@ -635,14 +651,14 @@ static ssize_t encodeDN(char *buf, size_t n, curl_asn1Element *dn) /* Encode attribute name. */ for(p3 = str; *p3; p3++) { - if(l < n) + if(l < buflen) buf[l] = *p3; l++; } free((char *) str); /* Generate equal sign. */ - if(l < n) + if(l < buflen) buf[l] = '='; l++; @@ -651,7 +667,7 @@ static ssize_t encodeDN(char *buf, size_t n, curl_asn1Element *dn) if(!str) return -1; for(p3 = str; *p3; p3++) { - if(l < n) + if(l < buflen) buf[l] = *p3; l++; } @@ -662,28 +678,30 @@ static ssize_t encodeDN(char *buf, size_t n, curl_asn1Element *dn) return l; } +/* + * Convert an ASN.1 distinguished name into a printable string. + * Return the dynamically allocated string, or NULL if an error occurs. + */ static const char *DNtostr(curl_asn1Element *dn) { - char *buf = (char *) NULL; - ssize_t n = encodeDN(buf, 0, dn); - - /* Convert an ASN.1 distinguished name into a printable string. - Return the dynamically allocated string, or NULL if an error occurs. */ + char *buf = NULL; + ssize_t buflen = encodeDN(NULL, 0, dn); - if(n >= 0) { - buf = malloc(n + 1); + if(buflen >= 0) { + buf = malloc(buflen + 1); if(buf) { - encodeDN(buf, n + 1, dn); - buf[n] = '\0'; + encodeDN(buf, buflen + 1, dn); + buf[buflen] = '\0'; } } - return (const char *) buf; + return buf; } /* - * X509 parser. + * ASN.1 parse an X509 certificate into structure subfields. + * Syntax is assumed to have already been checked by the SSL backend. + * See RFC 5280. */ - int Curl_parseX509(curl_X509certificate *cert, const char *beg, const char *end) { @@ -692,10 +710,6 @@ int Curl_parseX509(curl_X509certificate *cert, const char *ccp; static const char defaultVersion = 0; /* v1. */ - /* ASN.1 parse an X509 certificate into structure subfields. - Syntax is assumed to have already been checked by the SSL backend. - See RFC 5280. */ - cert->certificate.header = NULL; cert->certificate.beg = beg; cert->certificate.end = end; @@ -802,13 +816,14 @@ int Curl_parseX509(curl_X509certificate *cert, return 0; } + +/* + * Copy at most 64-characters, terminate with a newline and returns the + * effective number of stored characters. + */ static size_t copySubstring(char *to, const char *from) { size_t i; - - /* Copy at most 64-characters, terminate with a newline and returns the - effective number of stored characters. */ - for(i = 0; i < 64; i++) { to[i] = *from; if(!*from++) @@ -1105,15 +1120,15 @@ static const char *checkOID(const char *beg, const char *end, ccp = getASN1Element(&e, beg, end); if(!ccp || e.tag != CURL_ASN1_OBJECT_IDENTIFIER) - return (const char *) NULL; + return NULL; p = OID2str(e.beg, e.end, FALSE); if(!p) - return (const char *) NULL; + return NULL; matched = !strcmp(p, oid); free((char *) p); - return matched? ccp: (const char *) NULL; + return matched? ccp: NULL; } CURLcode Curl_verifyhost(struct connectdata *conn, |